TWI905245B - Methods for manufacturing liquid crystal components, liquid crystal display elements, and liquid crystal display elements - Google Patents

Abstract

A method for manufacturing a liquid crystal display element includes the following steps: in a state in which a liquid crystal composition containing liquid crystal and a free radical polymerizable compound represented by formula (A) is brought into contact with free radicals to form a film, the aforementioned free radical polymerizable compound is subjected to a polymerization reaction. In formula (A), M represents a polymerizable group capable of free radical polymerization; _R1 to _R3 each independently represent a single-bonded or intercalated alkyl group with 1 to 6 carbon atoms; Ar represents an aromatic hydrocarbon group that may also have substituents; _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that may also have substituents _{; R1X1} and _{R2X2 ,} along with the carbon atoms bonded to _R1X1 and _{R2X2 ,} may also form a ring. However, the total number _of carbon atoms in _R1X1 , _R2X2 , and _R3 must be 1 _{or more} .

Description

Manufacturing method of liquid crystal composition, liquid crystal display element, and liquid crystal display element

This invention relates to a method for manufacturing a liquid crystal display element that utilizes inexpensive and non-complex methods to produce a weak anchoring film and applies polymer-induced liquid crystal layer stabilization technology, as well as a liquid crystal display element for achieving lower voltage driving, liquid crystal compositions applicable to such components, and free radical polymerizable compounds.

In recent years, liquid crystal display (LCD) elements have been widely used in displays for mobile phones, computers, and televisions. LCD elements are characterized by their thinness, light weight, and low power consumption, and are expected to be used in VR (Virtual Reality), ultra-high-resolution displays, and many other applications in the future. Regarding the display methods of LCDs, various display modes have been proposed, including TN (Twisted Nematic), IPS (In-Plane Switching), and VA (Vertical Alignment). All modes use a film (liquid crystal alignment film) to guide the liquid crystals into a desired alignment state.

In particular, products with touch panels, such as tablet PCs, smartphones, and smart TVs, prefer to use the IPS mode, which is less prone to display interference even when touched. In recent years, considering the need to improve contrast and viewing angle characteristics, they have gradually begun to adopt liquid crystal display elements using FFS (Frindfield Switching) and non-contact technology using photo-alignment.

However, FFS has the following problems: compared to IPS, the substrate manufacturing cost is higher, and a display defect unique to FFS mode, known as Vcom offset, occurs. Furthermore, regarding photoalignment, it has advantages over the rubbing method, such as increasing the size of the manufactureable components and significantly improving display characteristics. However, there are inherent problems with the principle of photoalignment (if it is a decomposition type, the display defect originates from the decomposition products; if it is a isomerization type, the defect is due to insufficient alignment force causing burn-in, etc.). To solve these problems, liquid crystal display element manufacturers and liquid crystal alignment film manufacturers are currently making various efforts.

On the other hand, in recent years, some people have proposed using an IPS mode called weak anchor. It is reported that by using this method, the contrast can be improved and the voltage drive can be significantly reduced compared to the previous IPS mode (see Patent Document 1).

Specifically, it is a method of using a liquid crystal alignment film with strong anchoring energy on one side of the substrate, and applying a treatment to the other side of the substrate with an electrode that generates a transverse electric field to make it lose all alignment constraints of the liquid crystal, and using these to manufacture an IPS-mode liquid crystal display element.

In recent years, some researchers have used thick polymer brushes and other materials to create a weak anchoring state, and proposed a weak anchoring IPS mode technology (see Patent Document 2). This technology can achieve a significant improvement in contrast ratio and a significant reduction in drive voltage.

On the other hand, there is a problem with the response speed, especially the response speed when the voltage is OFF, which is significantly reduced. This is due to the lower driving voltage, which results in a weaker electric field compared to the usual driving method, and the fact that the liquid crystal takes longer to recover because the anchoring force of the alignment film is extremely small.

As a solution, one approach has been to weakly anchor the pixels only (see Patent 3). This is reportedly able to improve both brightness and response speed. [Prior Art Documents] [Patent Documents]

[Patent Document 1] Japanese Patent No. 4053530 [Patent Document 2] Japanese Unexamined Patent Application Publication No. 2013-231757 [Patent Document 3] Japanese Unexamined Patent Application Publication No. 2017-211566

[The problem the invention aims to solve]

By weakly anchoring only the electrodes of the IPS comb electrode, the response speed delay during driving is suppressed. On the other hand, in order to achieve a weak anchoring state only on the electrode, it is necessary to prepare difficult techniques such as coating different materials in very fine areas, which is believed to be a major challenge when it is actually industrialized.

Some researchers have explored different methods to reduce the cell gap in order to improve response speed. Generally, for liquid crystal display elements, a narrower cell gap tends to result in a faster response speed. However, on the other hand, there is a problem of reduced transmittance. To solve this problem, one approach is to use liquid crystals with a large birefringence difference (Δn). By setting the product of the cell gap D and Δn (the delay value) to 300nm–400nm (measured wavelength 550nm), the reduction in transmittance can be resolved. However, increasing Δn essentially does not only change this parameter; parameters such as Δε (dielectric anisotropy) and elasticity also change, thus it is believed that the fundamental properties of the liquid crystal will change significantly. For example, in the case of weak anchoring alignment, it is believed that liquid crystals may also align along the vertical direction. Therefore, obtaining stable weak anchoring characteristics even when parameters such as Δn and Δε change is an important issue.

It is believed that if such technical challenges can be solved, it will be a huge cost advantage for panel manufacturers, as well as an advantage in terms of battery consumption control and image quality improvement.

This invention addresses the aforementioned problems by providing a method for manufacturing a liquid crystal display (LCD) element. This method allows for the stable fabrication of a weakly anchored transverse electric field LCD element without pre-tilt angle during narrowing of the intercellular gap. Furthermore, it enables the fabrication of a transverse electric field LCD element that simultaneously achieves low driving voltage on/off response speeds and minimal VHR (voltage retention rate) reduction even at high temperatures. The invention also aims to provide such an LCD element, as well as liquid crystal compositions and free radical polymerizable compounds usable in these methods. [Means for Solving the Problems]

As a result of the inventors' diligent research in order to solve the above-mentioned problems, they discovered a solution to the problems and completed the present invention with the following key points.

That is, the present invention includes the following: [1] A method for manufacturing a liquid crystal display element, comprising the following steps: in a state in which a liquid crystal composition containing liquid crystal and a free radical polymerizable compound represented by the following formula (A) is brought into contact with free radicals to form a film, the aforementioned free radical polymerizable compound undergoes a polymerization reaction. [Chemical 1] In formula (A), M represents a polymerizable group capable of free radical polymerization, _R1 to _R3 each independently represent a single bond or an alkyl group with 1 to 6 carbon atoms that can also be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that can also have substituents, _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that can also have substituents _, and _the carbon atoms bonded _{to R1X1} and _R2X2 can also form a ring together _. However, the total number of carbon atoms of _R1X1 , _R2X2 and _R3 is 1 or _more . [2] In _the manufacturing method of the liquid crystal display element as described _in [1], _{R3 is} a linear alkyl group with 1 to 6 carbon atoms, and _X1 and _X2 are hydrogen atoms. [3] A method for manufacturing a liquid crystal display element as described in [1] or [2], wherein M in the aforementioned formula (A) is selected from the following structure. [Chemical 2] In the formula, * indicates the bonding site. ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms, and E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds and amide bonds. ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. [4] The manufacturing method of a liquid crystal display element according to any one of [1] to [3], wherein the aforementioned free radical generating film is a free radical generating film treated with uniaxial alignment. [5] The manufacturing method of a liquid crystal display element according to any one of [1] to [4], wherein the aforementioned polymerization reaction step is performed under conditions without an electric field. [6] A method for manufacturing a liquid crystal display element according to any one of [1] to [5], wherein the aforementioned free radical generating film is a film formed by immobilizing an organic group that induces free radical polymerization. [7] A method for manufacturing a liquid crystal display element according to any one of [1] to [5], wherein the aforementioned free radical generating film is obtained by coating and curing a composition containing a compound having an organic group that generates free radicals and a polymer to form a film, thereby immobilizing the aforementioned organic group that generates free radicals in the aforementioned film. [8] A method for manufacturing a liquid crystal display element according to any one of [1] to [5], wherein the aforementioned free radical generating film is composed of a polymer containing an organic group that induces free radical polymerization. [9] In the method for manufacturing a liquid crystal display element as described in [8], the polymer containing the organic group that induces free radical polymerization is selected from at least one polymer selected from polyimide precursors, polyimide, polyurea, and polyamide obtained by using a diamine component containing a diamine containing the organic group that induces free radical polymerization. [10] In the method for manufacturing a liquid crystal display element as described in [9], the organic group that induces free radical polymerization is an organic group represented by the following formula [X-1] to [X-18], [W], [Y], or [Z]. [Chemical 3] In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, and R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (among the aforementioned alkyl groups having 1 to 10 carbon atoms, the _-CH2- group of alkyl groups having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group of the aforementioned alkyl group is replaced by an oxygen atom, the aforementioned oxygen atom is not directly bonded to _S2 or N.). _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. [Chemistry 4] In formulas [W], [Y], and [Z], * indicates the bonding site; Ar represents an aromatic hydrocarbon selected from the group consisting of pentenyl, pentenyl-naphthyl, and pentenyl-biphenyl, which may also have organic groups and/or halogen atoms as substituents; ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms. When ^R9 and ^R10 are alkyl groups, they may also be terminally bonded to each other to form a ring structure. Q represents any of the following structures. [Chemistry 5] In the formula, R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-, where each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site. ^{S 3} represents a single bond, -O-, -NR- (R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms), or -S-. ^{R 12} represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. [11] In the manufacturing method of the liquid crystal display element as described in [9] or [10], the aforementioned diamine containing an organic group that induces free radical polymerization is a diamine having a structure represented by the following formula (6), the following formula (7), or the following formula (7'). [Chemical 6] In formula (6), ^R6 represents a single bond, _-CH2- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N(CH3)-, -CON( _{CH3 )} -, or -N( _CH3 )CO-, and ^R7 represents a single bond, or _an unsubstituted or fluorine-substituted alkyl group having 1 to 20 carbon atoms. Any one or more of _-CH2- or _-CF2- in the alkyl group can be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. In addition, any of the following groups, namely -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, can be replaced by such groups on the condition that they are not adjacent to each other; R ⁸ represents a radical polymerization reactive group selected from the following formulas [X-1] to [X-18]. [Chemistry 7] In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, and R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (among the aforementioned alkyl groups having 1 to 10 carbon atoms, the _-CH2- group of alkyl groups having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group of the aforementioned alkyl group is replaced by an oxygen atom, the aforementioned oxygen atom is not directly bonded to _S2 or N.). _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. [Chemistry 8] [Chemistry 9] In formulas (7) and (7'), ^T1 and ^T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N(CH3)-, -CON( _CH3 )-, or -N( _CH3 )CO-, and S represents a single bond, _or an unsubstituted or fluorine-substituted alkyl group with 1 to 20 carbon atoms. Any one or more of _-CH2- or _-CF2- of the alkyl group can also be independently replaced by a group selected from -CH= _CH- , a divalent carbon ring, and a divalent heterocyclic ring. In addition, any of the following groups, namely -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, can be replaced by such groups on the condition that they are not adjacent to each other. E represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 )m-, -SO2-, -O-(CH2) _m -O-, -OC( _CH3 ) _2- , -CO-(CH2) _m- , -NH-( _CH2 ) _m- , -SO2-( _CH2 ) _m- , -CONH-( _CH2 ) _m- , _-CONH- ( _CH2 ) _m -NHCO- _, or -COO-( _CH2 ) _m -OCO-, where _m is an integer from 1 to 8, and J is an organic group selected from the following formulas [W], [Y], and [ _Z ]. [Chemistry 10 _] In formulas [W], [Y], and [Z], * indicates the bonding site with ^T2 , Ar represents an aromatic hydrocarbon selected from the group consisting of pentenyl, pentenylnaphthyl, and pentenylbiphenyl, which may also have organic groups and/or halogen atoms as substituents, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Q represents any of the following structures. [Chemistry 11] In the formula, ^R11 represents _-CH2- , -NR-, -O-, or -S-, where each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site. ^S3 represents a single bond, -O-, -NR- (where R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms), or -S-. ^R12 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. In formula (7'), each q is independently 0 or 1, with at least one q being 1, and p represents an integer from 1 to 2. [12] A method for manufacturing a liquid crystal display element according to any one of [1] to [11] includes the following steps: preparing a first substrate having the aforementioned free radical generating film and a second substrate that may also have a free radical generating film; arranging the first substrate and the second substrate facing each other with the aforementioned free radical generating film in the first substrate facing the aforementioned second substrate; filling the aforementioned liquid crystal composition between the aforementioned first substrate and the aforementioned second substrate; and performing the aforementioned polymerization reaction. [13] A method for manufacturing a liquid crystal display element according to [12], wherein the aforementioned second substrate is a second substrate without a free radical generating film. [14] A method for manufacturing a liquid crystal display element according to [12], wherein the aforementioned second substrate is a substrate coated with a liquid crystal alignment film having uniaxial alignment. [15] A method for manufacturing a liquid crystal display element as described in [14], wherein the aforementioned liquid crystal alignment film having uniaxial alignment is a liquid crystal alignment film for horizontal alignment. [16] A method for manufacturing a liquid crystal display element as described in any one of [12] to [15], wherein either the aforementioned first substrate or the aforementioned second substrate is a substrate having comb-tooth electrodes. [17] A liquid crystal composition characterized by containing liquid crystal and a free radical polymerizable compound represented by the following formula (A). [Chemical 12] In formula (A), M represents a polymerizable group capable of free radical polymerization, _R1 to _R3 each independently represent a single bond or an alkyl group with 1 to 6 carbon atoms that can also be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that can also have substituents, _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that can also have substituents _, and _the carbon atoms bonded _{to R1X1} and _R2X2 can also form a ring together _. However, the total number _of carbon atoms of _R1X1 , _R2X2 and _R3 is 1 or _more . [18] As _in the liquid crystal composition of [17], in the aforementioned formula (A), _R3 is _a linear alkyl group with 1 to 6 carbon atoms, and _X1 and _X2 are hydrogen atoms. [19] Liquid crystal assemblies as in [17] or [18], wherein M in the aforementioned formula (A) is selected from the following structure. [Chemistry 13] In the formula, * indicates the bonding site. ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms, and E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds. ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. [20] A liquid crystal display element is characterized by having a first substrate, a second substrate disposed opposite to the first substrate, and liquid crystal filling the space between the first substrate and the second substrate; the liquid crystal composition containing the liquid crystal and the free radical polymerizable compound represented by the following formula (A) is subjected to a polymerization reaction of the free radical polymerizable compound in a state in which the free radical generating film of the first substrate having a free radical generating film is brought into contact. [Chemical 14] In formula (A), M represents a polymerizable group capable of free radical polymerization, _R1 to _R3 each independently represent a single bond or an alkyl group with 1 to 6 carbon atoms that can also be inserted into a bonding group, Ar represents an aromatic hydrocarbon group that can also have substituents, _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that can also have substituents _{, and the carbon atoms bonded to R1X1 and R2X2 can also form a ring together. However, the total number of carbon atoms of R1X1 , R2X2 and R3 is 1 or more . [ 21} ] In the liquid crystal display element of [20], either the first substrate or _the second substrate mentioned above is a substrate with a comb electrode. [22] Liquid crystal display elements such as those in [20] or [21] are low-voltage driven transverse electric field liquid crystal display elements. [23] A free radical polymerizable compound is characterized by the following formula (A). [Chemistry 15] In formula (A), M, _R1 , _R2 , _R3 , _X1 , _X2 , and Ar are any of the following combinations (i) to (v): (i) M is a combination of the following structures (C): _{R1X1 is} 1-pentyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a single bond, and Ar is a phenyl group. (ii) M is a combination of the following structures (B): _R1X1 is 1-propyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a single bond, _and Ar is a phenyl group. (iii) M is a combination of the following structures (C): _R1X1 is an ethyl _group , _R2X2 is an ethyl _group , _R3 is a 1,2-epenylethyl group, and Ar is a phenyl group. (iv) M has the following structure (C): _{R1X1 is} 1-propyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is 1,2-epenylethyl, and Ar is a phenyl group. (v) M has the following structure (D): _R1 is a single bond, _X1 is a hydrogen atom, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is 1,2-epenylethyl, and Ar is a phenyl group. [Chemistry 16] In structures (B), (C), and (D), * indicates a bonding location. [Effects of the Invention]

According to the present invention, a method for manufacturing a liquid crystal display element is provided, which can stably manufacture a weakly anchored transverse electric field liquid crystal display element without generating a pre-tilt angle when narrowing the intercellular gap, and can manufacture a transverse electric field liquid crystal display element that can simultaneously achieve low driving voltage and fast response speed when off, and has less reduction in VHR even at high temperatures; and can provide the liquid crystal display element, liquid crystal composition and free radical polymerizable compound that can be used in the above;

This invention utilizes an additive (a free radical polymerizable compound with a specific structure) that can suppress the occurrence of pre-tilt angles associated with the formation of weak anchoring films and can stably produce highly reliable weak anchoring transverse electric field liquid crystal display elements even when the intercellular gaps are narrowed. For example, it is a method for manufacturing a weak anchoring transverse electric field liquid crystal display element including the following steps: preparing a cell having a liquid crystal composition containing liquid crystal and a free radical polymerizable compound with a specific structure between a first substrate having a free radical generating film and a second substrate having a liquid crystal alignment film; and providing the aforementioned cell with energy sufficient to cause the aforementioned free radical polymerizable compound to undergo a polymerization reaction. A method for manufacturing a liquid crystal cell is preferred, comprising the following steps: preparing a first substrate having a free radical generating film after alignment treatment by rubbing or photoalignment, and a second substrate having a liquid crystal alignment film but not a free radical generating film; fabricating a cell with the substrates facing each other; and filling the space between the first and second substrates with a liquid crystal composition containing liquid crystal and a free radical polymerizable compound with a specific structure. For example, a method for manufacturing a low-voltage driven transverse electric field liquid crystal display element having an alignment-treated free radical generating film on one substrate and a liquid crystal alignment film treated by uniaxial alignment on another substrate, wherein either substrate is a substrate having a comb electrode for driving the liquid crystal.

In this invention, a "weak anchoring film" refers to a film in which there is no alignment constraint force on liquid crystal molecules in the in-plane direction, or even if there is, it is weaker than the intermolecular forces between liquid crystal molecules, and the film cannot enable liquid crystal molecules to uniaxially align in any direction. Furthermore, the weak anchoring film is not limited to solid films, but also includes liquid films covering solid surfaces. Typically, liquid crystal display elements use films that constrain the alignment of liquid crystal molecules in pairs, i.e., liquid crystal alignment films, to align the liquid crystals. However, the use of the weak anchoring film and the liquid crystal alignment film in pairs can also achieve liquid crystal alignment. This is because the alignment constraint force of the liquid crystal alignment film is also transmitted to the thickness direction of the liquid crystal layer through the intermolecular forces between liquid crystal molecules, resulting in liquid crystal molecules near the weak anchoring film also aligning. Therefore, when a liquid crystal alignment film for horizontal alignment is used, a horizontal alignment state can be created throughout the liquid crystal cell. Horizontal alignment refers to the state in which the long axes of liquid crystal molecules are arranged almost parallel to the liquid crystal alignment film surface. Inclined alignment of varying degrees is also included in the scope of horizontal alignment.

The applicant proposes a method for manufacturing a zero-plane anchoring film, comprising a step of providing sufficient energy to allow the aforementioned free radical polymerizable compound to undergo a polymerization reaction by contacting a liquid crystal composition containing liquid crystal and a free radical polymerizable compound with free radicals to form a film (see claim 1 of International Publication No. 2019/004433). Examples of the free radical polymerizable compound used in International Publication No. 2019/004433 are shown in [0077] to [0086]. In order to utilize the technology proposed above, the inventors have been actively exploring ways to stably fabricate a weakly anchored transverse electric field liquid crystal display element without generating a pre-tilt angle during narrowing of the cell interstices, and to fabricate a transverse electric field liquid crystal display element that simultaneously achieves faster response speeds during low drive voltage and off-state operations, and exhibits less VHR reduction at high temperatures. Their findings reveal that, by using a free radical polymerizable compound with a specific structure, a weakly anchored transverse electric field liquid crystal display element can be stably fabricated without generating a pre-tilt angle during narrowing of the cell interstices, and a transverse electric field liquid crystal display element that simultaneously achieves faster response speeds during low drive voltage and off-state operations, and exhibits less VHR reduction at high temperatures. Here, a free radical polymerizable compound with a specific structure is represented by the following formula (A). [Chemistry 17] In formula (A), M represents a polymerizable group capable of free radical polymerization; _R1 to _R3 each independently represent a single-bonded or intercalated alkyl group with 1 to 6 carbon atoms; Ar represents an aromatic hydrocarbon group that may also have substituents; _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that may also have substituents _{; R1X1} and _{R2X2 ,} along with the carbon atoms bonded to _R1X1 and _{R2X2 ,} may also form a ring. However, the total number _of carbon atoms in _R1X1 , _R2X2 , and _R3 must be 1 _{or more} .

The manufacturing method of the liquid crystal display element of this invention includes a step of bringing a liquid crystal composition containing liquid crystal and a free radical polymerizable compound represented by formula (A) into contact with a free radical generating film, thereby causing the free radical polymerizable compound to undergo a polymerization reaction. The inventors speculate that in this step, by utilizing the polymerization reaction of the free radical polymerizable compound generated from the free radical generating film, the surface of the free radical generating film changes, thus obtaining a weakly anchored film. However, it is difficult to confirm whether the change in the surface of the free radical generating film caused by this step is a change in the free radical generating film itself, or a change caused by the formation of a polymer layer of the free radical polymerizable compound on the free radical generating film. Therefore, the result obtained by this step has not yet been specifically identified.

In this invention, by performing the above steps, a weakly anchored transverse electric field liquid crystal display element can be stably fabricated without pre-tilt angle during narrowing of the intercellular gap. Furthermore, a transverse electric field liquid crystal display element can be manufactured that simultaneously achieves low driving voltage and fast response speed at off, and exhibits minimal VHR reduction at high temperatures. Regarding the contribution of the free radical polymerizable compound represented by formula (A), the inventors believe it is as follows: M of the free radical polymerizable compound represented by formula (A) contributes to the free radical polymerization of the free radical polymerizable compound. This allows the formation of a weakly anchored film and the realization of low driving voltage. Furthermore, the inventors of this case speculate that the Ar (or an aromatic hydrocarbon with substituents) in the free radical polymerizable compound represented by formula (A) contributes to the suppression of pretilt angle generation, the improvement of response rate, and the high VHR at high temperatures. Furthermore, the inventors of this case speculate that if M and Ar in formula (A) are not too close together, and there is a group of a certain size [-C( _R1X1 )( _R2X2 ) _R3- ] between M and Ar, it will have the effect of further accelerating _the response rate. In addition, in this specification, narrow intercellular gap refers to an intercellular gap of 3.5 _μm or less.

[Free Radical-Generating Film-Forming Composition] The free radical-generating film-forming composition used to form the free radical-generating film used in this invention contains, in terms of composition, a polymer and a free radical-generating group. This composition may be a polymer containing a free radical-generating group, or it may be a composition of a compound having a free radical-generating group and a polymer forming a base resin. By coating and curing such a composition to form a film, a free radical-generating film in which the free radical-generating group is immobilized can be obtained. The free radical-generating group is preferably an organic group that induces free radical polymerization.

The organic groups that induce free radical polymerization can be listed as those represented by the following formulas [X-1] to [X-18], [W], [Y], and [Z]. [Chemistry 18] In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, and R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (among the aforementioned alkyl groups having 1 to 10 carbon atoms, the _-CH2- group portion of the alkyl group having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group portion of the aforementioned alkyl group is replaced by an oxygen atom, the aforementioned oxygen atom is not directly bonded to _S2 or N.). _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. [Chemistry 19] In formulas [W], [Y], and [Z], * indicates the bonding site; Ar represents an aromatic hydrocarbon selected from the group consisting of pentenyl, pentenyl-naphthyl, and pentenyl-biphenyl, which may also have organic groups and/or halogen atoms as substituents; ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms. When ^R9 and ^R10 are alkyl groups, they may also be terminally bonded to each other to form a ring structure. Q represents any of the following structures. [Chem. 20] In the formula, ^R11 represents _-CH2- , -NR-, -O-, or -S-, where each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * indicates a bonding site. ^S3 represents a single bond, -O-, -NR- (where R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms), or -S-. ^R12 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

The polymer is preferably at least one polymer selected from the group consisting of polyimide precursors, polyimide, polyurea, polyamide, polyacrylate, polymethacrylate, and polyorganosiloxane.

In order to obtain the free radical generating membrane used in this invention, when using the aforementioned polymer having an organic group that induces free radical polymerization, it is preferable to use a monomer having a photoreactive side chain containing at least one of methacrylate, acrylic, vinyl, allyl, coumarin, styrene, and cinnamyl groups, and a monomer having a site in the side chain that decomposes upon ultraviolet irradiation and generates free radicals, as a monomer component for manufacturing. On the other hand, considering that monomers that generate free radicals may spontaneously polymerize and become unstable compounds, from the perspective of ease of synthesis, polymers derived from diamines with free radical generation sites are preferable, such as polyamides, polyamide esters and other polyimide precursors, polyimides, polyureas, and polyamides.

Polymers containing organic groups that induce free radical polymerization are preferably selected from at least one polymer chosen from polyimide precursors, polyimides, polyureas, and polyamides obtained using a diamine component containing a diamine containing organic groups that induce free radical polymerization. Specifically, such diamines containing organic groups that induce free radical polymerization are, for example, diamines having side chains capable of generating free radicals and undergoing polymerization. Examples of diamines having the structure represented by the following formula (6) are provided, but the selection is not limited thereto. [Chemistry 21] In formula (6), ^R6 represents a single bond, _-CH2- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N(CH3)-, _-CON ( _{CH3 )} -, or -N( _CH3 )CO-, and ^R7 represents a single bond, or an unsubstituted or fluorine-substituted alkyl group having 1 to 20 carbon atoms. Any one or more of _-CH2- or _-CF2- in the alkyl group can be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. In addition, any of the following groups can be replaced by such groups on the condition that -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH- are not adjacent to each other; R ⁸ represents a radical polymerization reactive group selected from the following formulas [X-1] to [X-18]. [Chemistry 22] In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, and R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms (among the aforementioned alkyl groups having 1 to 10 carbon atoms, the _-CH2- group of alkyl groups having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group of the aforementioned alkyl group is replaced by an oxygen atom, the aforementioned oxygen atom is not directly bonded to _S2 or N.). _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

The bonding positions of the two amino groups ( _-NH₂ ) in formula (6) are not limited. Specifically, the bonding groups relative to the side chain can be listed as positions 2,3, 2,4, 2,5, 2,6, 3,4, and 3,5 on the benzene ring. Considering the reactivity during the synthesis of polyamides, positions 2,4, 2,5, or 3,5 are preferable. Also considering the ease of synthesis of diamines, positions 2,4 or 3,5 are more preferred.

A diamine having a photoreactive group containing at least one group selected from the group consisting of methacrylate, acrylic, vinyl, allyl, coumarin, styrene, and cinnamyl, specifically, but not limited to, the following compounds. [Chem. 23] In the formula, ^J1 is selected from single bond, -O-, -COO-, -NHCO-, and -NH- bonding groups, and ^J2 represents a single bond, or an unsubstituted or fluorine-substituted alkyl group with 1 to 20 carbon atoms.

Among diamines containing organic groups that induce free radical polymerization, diamines with a side chain having a site that decomposes upon ultraviolet irradiation and generates free radicals can be listed, but are not limited to, those having the structures represented by formula (7) or formula (7'). [Chemistry 24] [Chemistry 25] In formulas (7) and (7'), ^T1 and ^T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N(CH3 ₎ -, -CON( _CH3 )-, or -N( _CH3 )CO-, and S represents a _single bond, or an unsubstituted or fluorine-substituted alkyl group having 1 to 20 carbon atoms. Any one or more of _-CH2- or _-CF2- of the alkyl group can also be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. In addition, any group listed below can be replaced by such groups on the condition that -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH- are not adjacent to each other. E represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 )m-, -SO2-, -O-(CH2) _m -O-, -OC( _CH3 ) _2- , -CO-(CH2) _m- , -NH-( _CH2 ) _m- , -SO2-( _CH2 ) _m- , -CONH-( _CH2 ) _m- , _-CONH- ( _CH2 ) _m -NHCO- _, or -COO-( _CH2 ) _m -OCO-, where _m is an integer from 1 to 8, and J is an organic group selected from the following formulas [W], [Y], and [Z] _. [Chemistry 26 _] In formulas [W], [Y], and [Z], * represents the bonding site with ^T2 ; Ar represents an aromatic hydrocarbon selected from the group consisting of pentenyl, pentenyl-naphthyl, and pentenyl-biphenyl, which may also have organic groups and/or halogen atoms as substituents; ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; and Q represents any of the following structures. [Chemistry 27] In the formula, ^R11 represents _-CH2- , -NR-, -O-, or -S-, where each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site. ^S3 represents a single bond, -O-, -NR- (where R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms), or -S-. ^R12 represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. In formula (7'), each q is independently 0 or 1, with at least one q being 1, and p represents an integer from 1 to 2.

The bonding positions of the two amino groups ( _-NH2 ) in the above formula (7) are not limited. Specifically, the bonding groups relative to the side chain can be listed as positions 2,3, 2,4, 2,5, 2,6, 3,4, and 3,5 on the benzene ring. Among these, considering the reactivity during the synthesis of polyacrylic acid, positions 2,4, 2,5, or 3,5 are preferred.

In particular, considering the ease of synthesis, versatility, and properties, the structure expressed by the following formula is optimal, but not limited to these. [Chemistry 28] In the formula, n is an integer from 2 to 8.

Among the diamines represented by formulas (7) and (7'), the structure represented by the following formula is the best, especially considering ease of synthesis, versatility, and properties, but is not limited to these. [Chemistry 29] In the formula, n is an integer from 2 to 8, E is a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -CONH-, -COO-, -OCO-, -( _CH2 ) _m- , -SO2-, -O-( _CH2 ) _m -O-, -OC( _CH3 ) _2- , -C(CH3) ₂ -O-, -CO-( _CH2 ) _m- , -( _CH2 ) _m -CO-, -NH-( _CH2 ) _m- , -( _CH2 ) _m -NH-, _-SO2- ( _CH2 ) _m- , -( _CH2 ) _m - _SO2- , -CONH-( _CH2 ) _m- , -( _CH2 ) _m -NHCO-, -CONH-( _CH2 ) _{m -} NHCO- or -COO-( _{CH2 )} ) _m -OCO-, where m is an integer from 1 to 8.

The diamines mentioned above can be used in combination, either one or two or more, depending on their properties such as liquid crystal alignment during the formation of free radical films, sensitivity during polymerization reactions, voltage retention characteristics, and stored charge.

The diamine containing organic groups that induce free radical polymerization should be used in an amount of 5 to 50 mol% of the total diamine component used in the synthesis of polymers contained in the free radical-generating film-forming components, more preferably 10 to 40 mol%, and even more preferably 15 to 30 mol%.

Furthermore, when obtaining the polymer used in the free radical generating membrane of this invention from diamines, other diamines besides the aforementioned diamines containing organic groups that induce free radical polymerization can be used as the diamine component, provided that the effect of this invention is not impaired. Specifically, examples include: p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-di Aminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonylurea diphenylamine, 3,3'-sulfonylurea diphenylamine, bis(phenyl) (4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'-diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl(4,4'-diaminodiphenyl)amine, N-methyl(3 3'-Diaminodiphenyl)amine, N-methyl(3,4'-diaminodiphenyl)amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'-diaminodiphenyl ketone, 3,3'-diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 2,2'-diaminodiphenyl ketone, 2,3'-diaminodiphenyl ketone, 1,4-diaminonaphthalene, 1,5-diaminonaphthalene, 1,6-diaminodiphenyl Naphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl) Methane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4’-[1,4-epenylphenylbis(methylene)]diphenylamine, 4,4’-[1,3-epenylphenylbis(methylene)]diphenylamine, 3,4’-[1,4-epenylphenylbis(methylene)]diphenylamine [Methyl]diphenylamine, 3,4'-[1,3-extrinylphenylbis(methylene)]diphenylamine, 3,3'-[1,4-extrinylphenylbis(methylene)]diphenylamine, 3,3'-[1,3-extrinylphenylbis(methylene)]diphenylamine, 1,4-extrinylphenylbis[(4-aminophenyl)methyl ketone], 1,4-extrinylphenylbis[(3-aminophenyl)methyl ketone], 1,3-extrinylphenylbis[(4-aminophenyl)methyl ketone], 1,3-extrinylphenylbis[(3-aminophenyl)methyl ketone] [Ketones], 1,4-Phenylbenzenebis(4-aminobenzoate), 1,4-Phenylbenzenebis(3-aminobenzoate), 1,3-Phenylbenzenebis(4-aminobenzoate), 1,3-Phenylbenzenebis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, N,N'-(1,4-Phenylbenzene)bis(4-aminophenyl)terephthalate N,N'-(1,3-aminobenzoxylamine), N,N'-(1,4-aminobenzoxylamine), N,N'-(1,4-aminobenzoxylamine), N,N'-(1,3-aminobenzoxylamine), N,N'-bis(4-aminobenzoxylamine), N,N'-bis(3-aminobenzoxylamine), N,N'-bis(4-aminobenzoxylamine), N,N'-bis(3-aminobenzoxylamine), N,N'-bis(4-aminobenzoxylamine), N,N'-bis(3-aminobenzoxylamine) 9,10-bis(4-aminophenyl)anthracene, 4,4'-bis(4-aminophenoxy)diphenyl sulfone, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2'-bis(3-aminophenyl)hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2, 2'-bis(4-aminophenyl)propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, trans-1,4-bis(4-aminophenyl)cyclohexane, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, bis(4-aminophenoxy)methane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,4-bis(3-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1,7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, Aromatic diethylcarbamates include 1,9-bis(4-aminophenoxy)octane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4-aminophenoxy)undecane, 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, and 1,12-bis(3-aminophenoxy)dodecane. Amines; alicyclic diamines such as bis(4-aminocyclohexyl)methane and bis(4-amino-3-methylcyclohexyl)methane; alicyclic diamines such as 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane; 1,3-bis[2-(para-) Diamines with a urea structure, such as [aminophenyl)ethyl]urea and 1,3-bis[2-(p-aminophenyl)ethyl]-1-tert-butoxycarbonylurea; diamines with a nitrogen-containing unsaturated heterocyclic structure, such as N-p-aminophenyl-4-p-aminophenyl(tert-butoxycarbonyl)aminomethylpiperidine; and diamines with an N-Boc group (Boc represents tert-butoxycarbonyl) such as N-tert-butoxycarbonyl-N-(2-(4-aminophenyl)ethyl)-N-(4-aminobenzyl)amine.

The other diamines mentioned above can be used in combination, depending on their properties such as liquid crystal alignment during free radical film formation, sensitivity during polymerization, voltage retention characteristics, and stored charge.

In the synthesis of polyamide polymers, there are no particular limitations on the tetracarboxylic acid dianhydride that reacts with the aforementioned diamine component. Specifically, examples include: pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracitetetracarboxylic acid, 1,2,5,6-anthracitetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl) ether, 3,3',4,4'-benzophenonetetracarboxylic acid, bis(3,4-dicarboxyphenyl) arsenate, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, and 1,1,1,3,3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl) Propane, bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenyltetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, oxydiphenyltetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4- Cyclobutanetetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxy-cyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydrofurantetracarboxylic acid -1-Naphthylsuccinic acid, bicyclic[3,3,0]octane-2,4,6,8-tetracarboxylic acid, bicyclic[4,3,0]nonane-2,4,7,9-tetracarboxylic acid, bicyclic[4,4,0]decane-2,4,7,9-tetracarboxylic acid, bicyclic[4,4,0]decane-2,4,8,10-tetracarboxylic acid, tricyclic[6.3]. [0.0＜2,6＞] Undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4-(2,5-dioxytetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic acid, 5-(2,5-dioxytetrahydrofuranyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo[6,2,1,1,0＜2,7＞] dodeca-4,5,9,10-tetracarboxylic acid, 3,5,6-tricarboxylated norbornene-2:3,5:6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, etc., are tetracarboxylic dianhydrides.

Of course, tetracarboxylic acid dianhydrides can also be used in combination with one or more depending on the characteristics such as liquid crystal alignment during the formation of free radical films, sensitivity in the polymerization reaction, voltage retention characteristics, and stored charge.

In the synthesis of polyamide esters, there are no particular limitations on the structure of the tetracarboxylic acid dialkyl ester that reacts with the above-mentioned diamine component. Specific examples are listed below.

Specific examples of aliphatic tetracarboxylic acid diesters include: 1,2,3,4-cyclobutanetetracarboxylate dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylate dialkyl ester, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylate dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylate dialkyl ester, 1,2,3,4- Dialkyl cyclopentanetetracarboxylate, dialkyl 2,3,4,5-tetrahydrofurantetracarboxylate, dialkyl 1,2,4,5-cyclohexanetetracarboxylate, dialkyl 3,4-dicarboxy-1-cyclohexylsuccinate, dialkyl 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthylsuccinate, dialkyl 1,2,3,4-butanetetracarboxylate, bicyclic [3,3,0]octyl Dialkyl alkyl-2,4,6,8-tetracarboxylic acid, dialkyl 3,3',4,4'-dicyclohexyltetracarboxylic acid, dialkyl 2,3,5-tricarboxylated cyclopentylacetic acid, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic acid, tricyclo[4.2.1.0＜2,5＞]nonane-3,4,7,8-tetracarboxylic acid-3,4 7,8-dialkyl esters, hexacyclo[6.6.0.1＜2,7＞.0＜3,6＞.1＜9,14＞.0＜10,13＞]hexadecane-4,5,11,12-tetracarboxylic acid-4,5:11,12-dialkyl esters, 4-(2,5-di-dioxytetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dialkyl esters, etc.

Aromatic tetracarboxylic acid dialkyl esters include: pyromellitic ester, 3,3',4,4'-biphenyltetracarboxylic acid dialkyl ester, 2,2',3,3'-biphenyltetracarboxylic acid dialkyl ester, 2,3,3',4-biphenyltetracarboxylic acid dialkyl ester, 3,3',4,4'-benzophenone tetracarboxylic acid dialkyl ester, 2,3,3',4'-benzophenone tetracarboxylic acid dialkyl ester, bis(3,4-dicarboxyphenyl) ether dialkyl ester, bis(3,4-dicarboxyphenyl) benzoyl dialkyl ester, 1,2,5,6-naphthalenetetracarboxylic acid dialkyl ester, 2,3,6,7-naphthalenetetracarboxylic acid dialkyl ester, etc.

In the synthesis of polyurea polymers, there are no particular limitations on the diisocyanate that reacts with the aforementioned diamine component, and it can be used depending on availability, etc. The specific structure of the diisocyanate is shown below. [Chem. 30] In the formula, _R2 and _R3 represent aliphatic hydrocarbons with 1 to 10 carbon atoms.

Aliphatic diisocyanates, as shown in K-1 to K-5, have poor reactivity but improve solvent solubility. Aromatic diisocyanates, as shown in K-6 to K-13, are highly reactive and improve heat resistance, but they also reduce solvent solubility. Considering versatility and performance characteristics, K-1, K-7, K-8, K-9, and K-10 are preferred; considering electrical properties, K-12 is preferred; and considering liquid crystal alignment, K-13 is preferred. Two or more diisocyanates can also be used together; the choice of diisocyanate should be based on the desired properties.

Furthermore, a portion of the diisocyanate can also be replaced with the tetracarboxylic dianhydride described above, which can be used in the form of a copolymer of polyamide and polyurea, or in the form of a copolymer of polyimide and polyurea by chemical imidization.

In the synthesis of polyamide polymers, the structure of the dicarboxylic acid involved in the reaction is not particularly limited. Specific examples are listed below. Aliphatic dicarboxylic acids include: malonic acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, mucoconic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, and octanoic acid, etc.

Alicyclic dicarboxylic acids include: 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, 1,3-cyclobutanedicarboxylic acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, and 1,2-cyclohexanedicarboxylic acid. Dicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4-(2-norcamphene)dicarboxylic acid, norcamphene-2,3-dicarboxylic acid, bicyclo[2.2.2]octane-1,4-dicarboxylic acid, bicyclo[2.2.2]octane-2,3-dicarboxylic acid, 2,5-dioxy-1,4-dicyclo[2.2.2]octanedicarboxylic acid, 1,3-adamantanedicarboxylic acid, 4,8-dioxy-1,3-adamantanedicarboxylic acid, 2,6-spiro[3.3]heptanedicarboxylic acid, 1,3-adamantanediacetic acid, camphoric acid, etc.

Aromatic dicarboxylic acids include: phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid, tetramethylterephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-anthraquinone dicarboxylic acid, 2,5-biphenyl dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, 1,5-epimidine dicarboxylic acid, 4,4'-triphenyldicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4,4'-diphenylethane dicarboxylic acid, 4,4'-diphenylpropane dicarboxylic acid, and 4,4'-diphenylhexafluoropropane. Dicarboxylic acid, 4,4’-diphenyl ether dicarboxylic acid, 4,4’-bibenzyl dicarboxylic acid, 4,4’-stilbene dicarboxylic acid, 4,4’-ethynyl dibenzoic acid, 4,4’-carbonyl dibenzoic acid, 4,4’-sulfonyl dibenzoic acid, 4,4’-dithiodibenzoic acid, p-phenyl diacetic acid, 3,3’-p-phenyl dipropionic acid, 4-carboxycinnamic acid, p-phenyl diacrylic acid, 3,3’-[4,4’-(methylene di-p-phenyl)]dipropionic acid, 4,4’-[4,4’-(oxy di-p-phenyl)]dipropionic acid, 4,4’-[4,4’-(oxy di-p-phenyl)]dibutyric acid, (isopropylidene di-p-phenyldioxy)dibutyric acid, bis(p-carboxyphenyl)dimethylsilane and other dicarboxylic acids.

Examples of heterocyclic dicarboxylic acids include: 1,5-(9-sideoxydicarboxylic acid), 3,4-furandicarboxylic acid, 4,5-thiazolyldicarboxylic acid, 2-phenyl-4,5-thiazolyldicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 1,2,5-diazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, and 3,5-pyridinedicarboxylic acid.

The aforementioned dicarboxylic acids can be acetal dihalides or anhydrides. These dicarboxylic acids, especially those providing linear structures for polyamides, are superior in maintaining the orientation of liquid crystal molecules. Among these, the following are ideally used: terephthalic acid, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenylethanedicarboxylic acid, 4,4'-diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis(phenyl)propanedicarboxylic acid, 4,4-triphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,5-pyridinedicarboxylic acid, or their acetal dihalides. These compounds may also exist as isomers or mixtures thereof. Furthermore, two or more compounds may be used. In addition, the dicarboxylic acids used in this invention are not limited to the compounds exemplified above.

Polyamides, polyamide esters, polyureas, and polyamides can be obtained by reacting a diamine (also referred to as "diamine component") with a component selected from tetracarboxylic dianhydride (also referred to as "tetracarboxylic dianhydride component"), tetracarboxylic acid diester, diisocyanate, and dicarboxylic acid. Generally, there are methods that involve reacting the diamine component with one or more components selected from tetracarboxylic dianhydride component, tetracarboxylic acid diester, diisocyanate, and dicarboxylic acid in an organic solvent.

The reaction between the diamine and tetracarboxylic dianhydride components is advantageous from the perspective that it can be carried out more easily in an organic solvent and does not produce byproducts.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve the polymer formed. Furthermore, even organic solvents that do not dissolve the polymer can be mixed with the solvents described above, provided that the polymer formed does not precipitate out. In addition, moisture in the organic solvent can hinder the polymerization reaction and thus cause the polymer to hydrolyze; therefore, dehydrated and dried organic solvents should be used.

For example, organic solvents include: N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidineone, 3-methoxy-N,N-dimethylpropanediamide, N-methylcaprolactone, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfoxide, hexamethyl sulfoxide, γ-butyrolactone, isopropanol, methoxymethylpentanol, dipentanol, etc. Alkenes, Ethylpentyl ketone, Methyl nonyl ketone, Methyl ethyl ketone, Methyl isopentyl ketone, Methyl isopropyl ketone, Methyl cyrosol, Ethyl cyrosol, Methyl cyrosol acetate, Butyl cyrosol acetate, Ethyl cyrosol acetate, Butyl carbitol, Ethyl carbitol, Ethyl glycol, Ethyl glycol monoacetate, Ethyl glycol monoisopropyl ether, Ethyl glycol monobutyl ether, Propylene glycol, Propylene glycol monoacetate, Propylene glycol monomethyl ether, Propylene glycol monobutyl ether, Propylene glycol-tert-butyl ether, Dipropylene glycol monomethyl ether, Propylene glycol monomethyl ether acetate, Diethylene glycol, Diethylene glycol monoethyl ether Ester, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dialkylene, n-hexane, n-pentane The solvents include n-octane, diethyl ether, cyclohexanone, ethyl acetate, propyl acetate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diethylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, and 2-ethyl-1-hexanol. These organic solvents can be used alone or in mixtures.

When reacting a diamine component with a tetracarboxylic dianhydride component in an organic solvent, the following methods can be used: stirring a solution obtained by dispersing or dissolving the diamine component in an organic solvent, and then directly adding the tetracarboxylic dianhydride component, or dispersing or dissolving it in an organic solvent before adding it; conversely, adding the diamine component to a solution obtained by dispersing or dissolving the tetracarboxylic dianhydride component in an organic solvent; or alternately adding the tetracarboxylic dianhydride component and the diamine component, etc. Any of these methods can be used. Furthermore, when the diamine component or the tetracarboxylic dianhydride component is composed of multiple compounds, they can be reacted in a pre-mixed state, or they can be reacted individually and sequentially. Alternatively, individually reacted low-molecular-weight polymers can be mixed and reacted to produce a high-molecular-weight polymer.

The temperature at which the diamine and tetracarboxylic dianhydride react can be any temperature, for example, -20 to 100°C, preferably in the range of -5 to 80°C. Furthermore, the reaction can be carried out at any concentration; for example, the total mass of the diamine and tetracarboxylic dianhydride relative to the reaction solution is 1 to 50% by mass, preferably 5 to 30% by mass.

The ratio of the total moles of the tetracarboxylic dianhydride components to the total moles of the diamine components in the above polymerization reaction can be chosen arbitrarily depending on the desired molecular weight of the polyamide. Similar to typical condensation reactions, the closer this mole ratio is to 1.0, the larger the molecular weight of the resulting polyamide. The ideal range is 0.8 to 1.2.

The method for synthesizing the polymer used in this invention is not limited to the above-described approach. When synthesizing polyamide, it can be done in the same way as conventional polyamide synthesis methods, by replacing the aforementioned tetracarboxylic acid dianhydride with a tetracarboxylic acid derivative such as a tetracarboxylic acid or tetracarboxylic acid dihalide, and reacting it using a known method to obtain the corresponding polyamide. Furthermore, in the synthesis of polyurea, a diamine can be reacted with a diisocyanate. In the manufacture of polyamide esters or polyamides, a diamine can be reacted with a component selected from tetracarboxylic acid diesters and dicarboxylic acids in the presence of a known condensing agent, or by a known method, to form a acetyl halide, and then reacted with the diamine.

Furthermore, polyimide can be obtained by cyclizing the aforementioned polyamide (nimidylation). In addition, the nimidation rate referred to in this specification refers to the proportion of nimidyl groups in the total amount of nimidyl and carboxyl groups derived from tetracarboxylic dianhydride. The nimidation rate in polyimide does not necessarily need to be 100% and can be adjusted arbitrarily according to the application and purpose. The nimidation rate of the polyimide in this invention is preferably 30% or higher, considering the improvement of voltage retention rate; on the other hand, considering the suppression of whitening properties, i.e., the precipitation of the polymer in the varnish, it is preferably 80% or lower.

Methods for producing polyimide by amide-imidizing the above-mentioned polyacrylic acid can be listed as follows: thermal amide-imidization by directly heating a polyacrylic acid solution; and catalytic amide-imidization by adding a catalyst to a polyacrylic acid solution. The temperature for thermal amide-imidization of polyacrylic acid in solution is typically 100–400°C, preferably 120–250°C, and it is preferable to remove the water generated during the amide-imidization reaction to the outside of the system.

Catalytic amide imidization of polyamides can be carried out by adding an alkaline catalyst and an acid anhydride to a polyamide solution, typically at -20 to 250°C, preferably 0 to 180°C with stirring. The amount of alkaline catalyst is typically 0.5 to 30 moles of amide groups, preferably 2 to 20 moles, and the amount of acid anhydride is typically 1 to 50 moles of amide groups, preferably 3 to 30 moles. Examples of alkaline catalysts include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among these, pyridine is preferred due to its appropriate alkalinity for the reaction to proceed. Acid anhydrides include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among these, acetic anhydride is preferred because it facilitates purification after the reaction. The acetilimation rate obtained by catalytic acetilimation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

When recovering polymer from a polymer reaction solution, the reaction solution is simply added to a poor solvent to precipitate it. Poor solvents used for precipitation include: methanol, acetone, hexane, butylceryl ketone, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polymer precipitated in the poor solvent can be filtered and recovered, and then dried at room temperature or under reduced pressure. Furthermore, repeating the process of redissolving the recovered polymer in an organic solvent and reprecipitating it 2 to 10 times can reduce impurities in the polymer. The undesirable solvents at this time include, for example, alcohols, ketones, and hydrocarbons. Using three or more of these undesirable solvents will further improve the refining efficiency, which is better.

Furthermore, when the aforementioned free radical generating membrane is composed of a polymer containing organic groups that induce free radical polymerization, the free radical generating membrane forming composition used in this invention may also include polymers other than those containing organic groups that induce free radical polymerization. In this case, the content of other polymers in the total polymer composition is preferably 5-95% by mass, more preferably 30-70% by mass.

When considering the strength, workability during coating, and uniformity of the free radical-generating film obtained by coating the free radical-generating film-forming composition, the weight-average molecular weight measured by GPC (Gel Permeation Chromatography) should preferably be 5,000 to 1,000,000, more preferably 10,000 to 150,000.

By coating a composition of a compound and a polymer containing a free radical-generating group and curing it to form a film, the free radical-generating film used in this invention is immobilized in the film. The polymer used can be selected from the group consisting of polyimide precursors prepared by the above-described manufacturing method, and polyimide, polyurea, polyamide, polyacrylate, polymethacrylate, etc. Furthermore, the diamine containing the organic group that induces free radical polymerization is at least one polymer obtained by using 0 moles of the diamine component used in the synthesis of the polymer contained in the free radical-generating film forming composition. The compound containing the free radical-generating group added at this time can be listed below.

Compounds that generate free radicals through heat are those that produce free radicals by being heated above their decomposition temperature. Examples of such free radical thermal polymerization initiators include: peroxide ketones (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacetyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydrogen peroxides (hydrogen peroxide, tert-butyl hydrogen peroxide, cumene hydrogen peroxide, etc.), and dialkyl peroxides (di-tert-butyl peroxide, dicumene peroxide, dilauryl peroxide, etc.). Examples of free radical thermal polymerization initiators include: peroxide ketals (such as dibutylcyclohexane peroxide), alkyl peroxide esters (such as tert-butyl neodecanoate, tert-butyl trimethylacetic acid peroxide, and tert-pentyl peroxide-2-ethylcyclohexanoate), persulfates (such as potassium persulfate, sodium persulfate, and ammonium persulfate), and azo compounds (such as azobisisobutyronitrile and 2,2'-di(2-hydroxyethyl)azobisisobutyronitrile). These free radical thermal polymerization initiators can be used alone or in combination of two or more.

Compounds that generate free radicals using light are not particularly limited in scope, as long as they are compounds that initiate free radical polymerization upon light irradiation. Examples of such free radical photopolymerization initiators include: benzophenone, milchler's ketone, 4,4'-bis(diethylamino)benzophenone, oxanthraphenone, thiotonone, isopropyloxanthraphenone, 2,4-diethylthiotonone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylphenylacetone, 2-hydroxy-2-methyl-4'-isopropylphenylacetone, 1-hydroxycyclohexylphenyl ketone, isopropyl phenozinole, isobutyl phenozinole, 2,2-diethoxyacetophenone, and 2,2-dimethoxy-2-phenylacetophenone. Ketones, camphorquinone, benzanthrone, 2-methyl-1-[4-(methylthio)phenyl]-2-hydroxylpropane-1-one, 2-benzyl-2-dimethylamino-1-(4-hydroxylphenyl)-butanone-1,4-dimethylaminobenzoate ethyl ester, 4-dimethylaminobenzoate isoamyl ester, 4,4’-bis(tert-butylperoxycarbonyl)benzophenone, 3,4,4’-tris(tert-butylperoxycarbonyl)benzophenone, 2,4,6-tris(tert-butylperoxycarbonyl)benzophenone Methylbenzoyl diphenylphosphine oxide, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-( 4’-pentyloxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[p-N,N-di(ethoxycarbonylmethyl)]-2,6-bis(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2’-chlorophenyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(4’-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzo[a]azole, 2-(p-dimethylamino] Styrene-based benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetra(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2,4- (2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropyl)carbazole, 3,6-bis(2-methyl-2-hydroxylaminopropyl) -9-Dodecylcarbazole, 1-Hydrocyclohexylphenyl ketone, bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrolo-1-yl)-phenyl)titanium, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3',4,4'-tetra(tert-hexylperoxycarbonyl)benzophenone, 3,3'-di(methoxycarbonyl)-4,4'-di(tert-butylperoxycarbonyl) Benzyl ketone, 3,4'-di(methoxycarbonyl)-4,3'-di(tert-butylperoxycarbonyl)benzophenone, 4,4'-di(methoxycarbonyl)-3,3'-di(tert-butylperoxycarbonyl)benzophenone, 2-(3-methyl-3H-benzothiazol-2-ylidene)-1-naphth-2-yl-ethyl ketone, or 2-(3-methyl-1,3-benzothiazol-2(3H)-ylidene)-1-(2-benzoyl)ethyl ketone, etc. These compounds can be used alone or in combination of two or more.

Furthermore, when the aforementioned free radical generating membrane is composed of a polymer containing an organic group that induces free radical polymerization, it may also contain a compound having the aforementioned free radical generating group in order to promote free radical polymerization when energy is provided.

The free radical generating film-forming composition may contain an organic solvent that dissolves or disperses the polymer components and, if necessary, other components besides the free radical generator. There are no particular limitations on such organic solvents; for example, the organic solvents exemplified in the synthesis of polyamides described above can be listed. Among these, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidineone, and 3-methoxy-N,N-dimethylpropanediamine are preferred from a solubility perspective. N-methyl-2-pyrrolidone or N-ethyl-2-pyrrolidone are particularly suitable, and mixtures of two or more solvents may also be used.

Furthermore, it is advisable to use solvents that improve the uniformity and smoothness of the coating in combination with organic solvents that have high solubility in components of free radical-generated film-forming components.

Solvents used to improve the uniformity and smoothness of coatings include, for example: isopropanol, methoxymethylpentanol, methyl cyrosol, ethyl cyrosol, butyl cyrosol (ethylene glycol monobutyl ether), methyl cyrosol acetate, butyl cyrosol acetate, ethyl cyrosol acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, and propylene glycol monobutyl ether. Propylene glycol tributyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, di... Isopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methyl cyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3-methoxy Ethyl propionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, 2-ethyl-1-hexanol, etc. These solvents can also be mixed in multiples. When using these solvents, it is preferable that they constitute 5-80% by mass of the total solvent content in the free radical-generating film-forming component, more preferably 20-60% by mass.

Free radical-generated film-forming components may also contain components other than those mentioned above. Examples include: compounds that improve the uniformity of film thickness and surface smoothness when coating free radical-generated film-forming components; compounds that improve the adhesion between free radical-generated film-forming components and substrates; and compounds that further improve the film strength of free radical-generated film-forming components.

Compounds used to improve film thickness uniformity and surface smoothness include fluorinated surfactants, polysiloxane surfactants, and nonionic surfactants. More specifically, examples include: EFTOP EF301, EF303, EF352 (manufactured by Mitsubishi Materials Electronic Chemicals), Megafac F171, F173, R-30 (manufactured by DIC), Fluorad FC430, FC431 (manufactured by 3M), AsahiGuard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC), etc. When using such surfactants, the proportion of their use relative to 100 parts by mass of the total polymer contained in the free radical generating film forming component is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass.

Specific examples of compounds that improve the adhesion between free radical-generated film-forming components and the substrate include compounds containing functional silanes and compounds containing epoxy groups. Examples include: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, and N-ethoxycarbonyl-3-aminopropyltrimethoxysilane. N-Triethoxysilane, N-Triethoxysilylpropyltriethylenetriamine, N-Trimethoxysilylpropyltriethylenetriamine, 10-Trimethoxysilyl-1,4,7-triazadecane, 10-Triethoxysilyl-1,4,7-triazadecane, 9-Trimethoxysilyl-3,6-diazanonylacetate, 9-Triethoxysilyl-3,6-diazanonylacetate, N-Benzyl-3-aminopropyltrimethoxysilane, N-Benzyl-3-aminopropyltriethoxysilane N-Phenyl-3-aminopropyltrimethoxysilane, N-Phenyl-3-aminopropyltriethoxysilane, N-bis(oxyethyl)-3-aminopropyltrimethoxysilane, N-bis(oxyethyl)-3-aminopropyltriethoxysilane, ethylene glycol diepoxypropyl ether, polyethylene glycol diepoxypropyl ether, propylene glycol diepoxypropyl ether, tripropylene glycol diepoxypropyl ether, polypropylene glycol diepoxypropyl ether, neopentyl glycol diepoxypropyl ether, 1,6-hexanediol diepoxypropyl ether, glycerol diepoxypropyl ether, 2, 2-Dibromoneopentyl glycol diepoxypropyl ether, 1,3,5,6-tetracyclooxypropyl-2,4-hexanediol, N,N,N’,N’-tetracyclooxypropyl-m-xylenediamine, 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane, N,N,N’,N’-tetracyclooxypropyl-4,4’-diaminodiphenylmethane, 3-(N-allyl-N-epoxypropyl)aminopropyltrimethoxysilane, 3-(N,N-diepoxypropyl)aminopropyltrimethoxysilane, etc.

Furthermore, to further enhance the membrane strength of the free radical generating membrane, phenolic compounds such as 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane and tetra(methoxymethyl)bisphenol can be added. When using these compounds, the amount is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, relative to 100 parts by mass of the total polymer contained in the free radical generating membrane forming composition.

In addition to the above, in the free radical generating film forming composition, dielectrics and conductive materials that change the electrical properties such as dielectric and conductivity of the free radical generating film may also be added, without impairing the effect of the present invention.

[Free Radical Generation Film] The free radical generation film of this invention can be obtained, for example, using the aforementioned free radical generation film forming composition. For example, a hardened film can be obtained by coating the free radical generation film forming composition used in this invention onto a substrate, followed by drying and calcination, and this hardened film can be used directly as a free radical generation film. Furthermore, the hardened film can be aligned using methods such as friction, irradiation with polarized light or light of a specific wavelength, or ion beams. In the case of alignment films for PSA systems, UV irradiation can also be applied to liquid crystal display elements after liquid crystal filling.

The substrate for coating free radical-generated film to form a composition is not particularly limited as long as it is a highly transparent substrate. It is preferable to form a substrate on which transparent electrodes for driving liquid crystals are formed.

Specific examples include substrates with transparent electrodes formed on plastic sheets such as glass plates, polycarbonate, poly(meth)acrylate, polyether ether, polyarylate, polyurethane, polyether, polyetherketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth)acrylonitrile, triacetylcellulose, 2,3-butanedione cellulose, and acetate butyrate cellulose.

The substrates that can be used for IPS mode liquid crystal display elements can also use standard IPS comb electrodes, PSA fishbone electrodes, and MVA protrusion patterns.

Furthermore, in high-function components such as TFT-type components, a transistor-like element is formed between the electrode used to drive the liquid crystal and the substrate.

When manufacturing transmissive liquid crystal display elements, the substrates described above are generally used. However, when manufacturing reflective liquid crystal display elements, if the substrate is only on one side, an opaque substrate such as a silicon wafer can also be used. In this case, the electrodes formed on the substrate can also be made of materials that reflect light, such as aluminum.

Methods for coating components that generate free radicals to form films include spin coating, printing, inkjet coating, spray coating, and roller coating. However, considering productivity, transfer printing is widely used in industry and can also be ideally used in this invention.

A drying step after the coating free radical-generated film is not necessary. However, if the time from coating to calcination on each substrate is not fixed, or if calcination is not performed immediately after coating, a drying step should be included. The drying process only needs to remove the solvent to a level that will not cause deformation of the coating shape due to substrate transport, etc. There are no particular limitations on the drying method. For example, drying on a heated plate at a temperature of 40–150°C, preferably 60–100°C, for 0.5–30 minutes, preferably 1–5 minutes, can be listed.

The coating formed by the free radical-generated film-forming composition applied using the above method can be calcined to produce a hardened film. The calcination temperature can typically be any temperature between 100 and 350°C, preferably 140 to 300°C, more preferably 150 to 230°C, and even more preferably 160 to 220°C. The calcination time can typically be any duration between 5 and 240 minutes, preferably 10 to 90 minutes, and more preferably 20 to 90 minutes. Heating can be performed using conventional methods, such as heating plates, hot air circulating ovens, IR (infrared) ovens, or belt furnaces.

The thickness of the curing film can be selected as needed, but it is preferable to be 5nm or more, and even better to be 10nm or more, as this improves the reliability of the liquid crystal display element. Furthermore, it is preferable to have a curing film thickness of 300nm or less, and even better to have a thickness of 150nm or less, as this prevents the power consumption of the liquid crystal display element from becoming extremely high.

A first substrate having a free radical generating film can be obtained in the above manner, but the free radical generating film can be subjected to uniaxial alignment treatment. Methods for performing uniaxial alignment treatment include photoalignment, oblique evaporation, friction, and uniaxial alignment treatment using a magnetic field.

When alignment is performed by unidirectional friction, for example, the substrate is moved by rotating a friction roller wound with friction cloth while the friction cloth contacts the film. When using photoalignment, alignment is performed by irradiating the entire film with polarized UV light of a specific wavelength and heating as needed. In the case of the first substrate of this invention with comb-tooth electrodes, the orientation is selected using the electrical properties of the liquid crystal. However, when using a liquid crystal with positive dielectric anisotropy, the friction direction should preferably be approximately the same as the extension direction of the comb-tooth electrodes.

Regarding the steps for creating weak and strong anchoring regions, methods such as irradiating the area with radiation in any pattern using a photoresist shield can be cited. This involves pre-irradiating the free radical-generating film with radiation to eliminate the free radical generation site and prevent it from becoming weakly anchored. Radiation used in this step can include polarized light, light of a specific wavelength, or ion beams. Irradiating the area corresponding to the photofree radical generation site with the highest absorbance at that wavelength is particularly effective.

The second substrate of this invention may or may not have a free radical generating film. The second substrate is preferably a substrate with a liquid crystal alignment film that is known in the past.

In this invention, the first substrate is a substrate with comb-tooth electrodes, and the second substrate may also be a counter substrate. Alternatively, in this invention, the second substrate is a substrate with comb-tooth electrodes, and the first substrate may also be a counter substrate.

<Liquid Crystal Cell> The liquid crystal cell of this invention can be obtained by forming a free radical generating film on a substrate using the method described above, then arranging the substrate with the free radical generating film (first substrate) and a conventional substrate with a liquid crystal alignment film (second substrate) with the free radical generating film facing each other, clamping a spacer, fixing it with a sealant, injecting a liquid crystal composition containing liquid crystal and a free radical polymerizing compound, and sealing it. The size of the spacer used is typically 1–30 μm, preferably 2–10 μm.

There are no particular limitations on the method of injecting liquid crystal compositions containing liquid crystals and free radical polymerizable compounds. Examples include: vacuum method, which involves depressurizing the prepared liquid crystal cells and then injecting a mixture containing liquid crystals and polymerizable compounds; and drop method, which involves adding a mixture containing liquid crystals and polymerizable compounds and then sealing it.

<Free Radical Polymerizing Compounds and Liquid Crystal Components> The free radical polymerizing compounds of the present invention are represented by the following formula (A). [Chemical 31] In formula (A), M represents a polymerizable group capable of free radical polymerization; _R1 to _R3 each independently represent a single-bonded or intercalated alkyl group with 1 to 6 carbon atoms; Ar represents an aromatic hydrocarbon group that may also have substituents; _X1 and _X2 each independently represent a hydrogen atom or an aromatic hydrocarbon group that may also have substituents _{; R1X1} and _{R2X2 ,} along with the carbon atoms bonded to _R1X1 and _{R2X2 ,} may also form a ring. However, the total number _of carbon atoms in _R1X1 , _R2X2 , and _R3 must be 1 _{or more} .

An alkyl group with 1 to 6 carbon atoms that has an inserted bonding group refers to an alkyl group with a divalent bonding group inserted between carbon atoms within the alkyl group with 1 to 6 carbon atoms, or an alkyl group with a divalent bonding group inserted between the alkyl group with 1 to 6 carbon atoms and the carbon atom to which it is bonded. Examples of bonding groups include carbon-carbon unsaturated bonds, ether bonds (-O-), ester bonds (-COO- or -OCO-), and amide bonds (-CONH- or -NHCO-). Examples of unsaturated bonds include carbon-carbon double bonds. For alkyl groups with 1 to 6 carbon atoms that have an inserted carbon-carbon double bond, the carbon-carbon double bond should preferably be internal rather than terminal. Alkyl groups having 1 to 6 carbon atoms can also be inserted as bonding groups, such as alkyl groups having 1 to 6 carbon atoms and alkyl groups having 1 to 6 carbon atoms. The oxygen atom in the alkyl group having 1 to 6 carbon atoms is bonded to the carbon atoms bonded to M, _R1 , _R2 , and _R3 in formula (A). Alkyl groups having 1 to 6 carbon atoms can be linear alkyl groups, branched alkyl groups, or cyclic alkyl groups.

Aromatic hydrocarbons may also have substituents, such as phenyl and naphthyl groups. Substituents may include, for example, halogen atoms, alkyl groups with 1 to 4 carbon atoms, alkoxy groups with 1 to 4 carbon atoms, halogenated alkyl groups with 1 to 4 carbon atoms, and halogenated alkoxy groups with 1 to 4 carbon atoms. The halogenation in halogenated alkyl groups and halogenated alkoxy groups can be complete or partial. Halogen atoms may include, for example, fluorine atoms and chlorine atoms.

R _1, for example, can include single-bonded alkyl groups with 1 to 6 carbon atoms. More specifically, linear alkyl groups with 1 to 6 carbon atoms can be listed. R ₂ , for example, can include single-bonded alkyl groups with 1 to 6 carbon atoms. More specifically, linear alkyl groups with 1 to 6 carbon atoms can be listed. R ₃ , for example, can include single-bonded alkyl groups with 1 to 6 carbon atoms. More specifically, linear alkyl groups with 1 to 6 carbon atoms can be listed. X _1, for example, can include hydrogen atoms, phenyl groups, etc. X ₂ , for example, can include hydrogen atoms, phenyl groups, etc. Ar, for example, can include phenyl groups, etc.

If the total number of carbon atoms in _R1X1 , _R2X2 , and _R3 is 1 or _more , there is no particular limitation, and it can be 2 or _more . Furthermore, the total number of carbon atoms in _R1 , _{R2 ,} and _R3 can be, for example, 18 or less, 15 or less, or 10 or less. Also, when _X1 and _X2 are hydrogen atoms, if the total number of carbon atoms in _R1 , _{R2 ,} and _R3 is 1 or more, there is no particular limitation, and it can be 2 or more. In addition, if at least one of _X1 and _X2 is an aromatic hydrocarbon that may also have substituents, the total number of carbon atoms in _R1 , _{R2 ,} and _R3 can also be 0.

The rings formed by _R1X1 and _R2X2 and the carbon atoms bonded to _{R1X1 and R2X2} can _{be exemplified} by hydrocarbon rings with 3 to 13 carbon atoms _, or can be inserted into the bonding group. The bonding group is as described above.

Examples of free radical polymerizable compounds represented by formula (A) include those represented by formulas (A-1) to (A-3). [Chemistry 32] In the formula, M represents a polymerizable group capable of free radical polymerization; _R1 to _R3 each independently represent a single-bonded or alkyl group with 1 to 6 carbon atoms that can also insert into a bonding group; Ar, _Ar1 , and _Ar2 each independently represent an aromatic hydrocarbon group that can also have substituents; and _R11 and _R12 each independently represent a hydrogen atom or an alkyl group with 1 to 6 carbon atoms that can also insert into a bonding group. In formula (A-1), _R11 and _R12 can also form a ring together with the carbon atoms bonded to _R11 and _R12 . In formula (A-1), the total number of carbon atoms of _R11 , _R12 , and _R3 can be 1 or more, or 2 or more. Furthermore, the total number of carbon atoms can be 18 or less, 15 or less, or 10 or less. In formula (A-2), the total number of carbon atoms in _R1 , _R12 , and _R3 is not particularly limited and can be 0. The total number of carbon atoms can be, for example, 18 or less, 15 or less, or 10 or less. In formula (A-3), the total number of carbon atoms in _R1 , _R2 , and _R3 is not particularly limited and can be 0. The total number of carbon atoms can be, for example, 18 or less, 15 or less, or 10 or less. Furthermore, _R11 refers to the case where _X1 in _R1 x ₁ is a hydrogen atom. _R12 refers to the case where _X2 in _R2 x ₂ is a hydrogen atom.

Furthermore, the polymerizable group M of the aforementioned free radical polymerizable compound, capable of free radical polymerization, should preferably be a polymerizable group selected from the following structures. [Chemistry 33] In the formula, * indicates the bonding site. ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms, and E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds. ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms.

Free radical polymerizable compounds contained in formulas (A) and (A-1), for example, include the following free radical polymerizable compounds. [Chemistry 34]

(i) Add-1 is equivalent to M in formula (A) having the following structure (C): _R1X1 is ₁ -pentyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a single bond, and Ar is a phenyl combination. (ii) Add-3 is equivalent to M in formula (A) having the following structure (B): _{R1X1 is} 1-propyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a single bond, and Ar is a phenyl combination. (iii) Add-6 is equivalent to M in formula (A) having the following structure (C): _{R1X1 is} ethyl, _R2X2 is _ethyl , _R3 is 1,2-epenylethyl, and Ar is a phenyl combination. (iv) Add-8 shall be a combination of the following structures (C) in formula (A): _{R1 X1} is 1-propyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is 1,2-epenylethyl, and Ar is a phenyl group. (v) Add-12 shall be a combination of the following structures (D) in formula (A): _R1 is a single bond, _X1 is a hydrogen atom, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is 1,2-epenylethyl, and Ar is a phenyl group. [Chem. 35] In structures (B), (C), and (D), * indicates a bonding location.

The liquid crystal composition contains at least liquid crystal and the aforementioned free radical polymerizable compound. The content of the aforementioned free radical polymerizable compound in the liquid crystal composition, relative to the total mass of the liquid crystal and the free radical polymerizable compound, is preferably 0.5% by mass or more, more preferably 1% by mass or more, preferably 10% by mass or less, and more preferably 5% by mass or less.

Furthermore, liquid crystal compositions may also use various compounds with other monofunctional free radical polymerizable groups that are different from the aforementioned free radical polymerizable compounds (hereinafter, sometimes referred to as "other free radical polymerizable compounds").

Other free radical polymerizable compounds are those containing unsaturated bonds that can undergo free radical polymerization in the presence of organic free radicals. Examples include: methacrylate monomers such as tributyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, lauryl methacrylate, and n-octyl methacrylate; acrylate monomers such as tributyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, lauryl acrylate, and n-octyl acrylate; and styrene and styrene derivatives (e.g., ortho-, meta-, and p-methoxystyrene, ortho-, meta-, and p-tetroxystyrene, ortho-, meta-, and p-chloromethoxystyrene). Vinyl monomers, including but not limited to, styrene, vinyl esters (e.g., vinyl acetate, vinyl propionate, vinyl benzoate), vinyl ketones (e.g., vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone), N-vinyl compounds (e.g., N-vinylpyrrolidone, N-vinylpyrrole, N-vinylcarbazole, N-vinylindole), (meth)acrylic acid derivatives (e.g., acrylonitrile, methacrylonitrile, acrylamide, isopropyl acrylamide, methacrylamide), and halogenated vinyl compounds (e.g., vinyl chloride, vinylidene chloride, tetrachloroethylene, hexachlorobutadiene, fluorinated vinylides). Furthermore, these monomers should preferably be compatible with liquid crystals.

Furthermore, other free radical polymerizable compounds represented by formula (1) are also preferred. [Chemistry 36] In formula (1), ^Ra and ^Rb each independently represent a straight-chain alkyl group having 2 to 8 carbon atoms, and E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds. ^Rc represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

At least one of the free radical polymerizable compounds contained in the liquid crystal composition is preferably a compound having a polymerizable unsaturated bond in a molecule that is compatible with the liquid crystal, that is, a compound having a monofunctional free radical polymerizable group.

Furthermore, regarding the free radical polymerizable compound represented by the aforementioned formula (1), those in which E is an ester bond (represented by -C(＝O)-O- or -OC(＝O)-) are preferable from the perspectives of ease of synthesis, compatibility with liquid crystals, and polymerization reactivity. Specifically, compounds with the following structure are preferable, but there are no particular limitations. [Chemistry 37] Furthermore, the liquid crystal composition should preferably contain a free radical polymerizing compound whose polymer, obtained by polymerizing a free radical polymerizing compound, has a Tg of 100°C or less.

These various free radical polymerizable monomers can be used alone or in combination of two or more. Furthermore, they should be compatible with liquid crystals.

The polymer obtained by polymerizing free radical polymerizable compounds should preferably have a Tg below 100°C, and more preferably below 0°C.

Furthermore, liquid crystals generally refer to substances that exhibit both solid and liquid properties. Representative liquid crystal phases include nematic liquid crystals and saturated liquid crystals. There are no particular limitations on the liquid crystals that can be used in this invention. For example, 4-pentyl-4'-cyanobiphenyl.

Then, sufficient energy is provided to the liquid crystal cells containing the mixture of liquid crystal and free radical polymerizable compound (liquid crystal composition) to induce a polymerization reaction of the free radical polymerizable compound. This can be achieved, for example, by heating or UV irradiation, through which the free radical polymerizable compound polymerizes in situ, exhibiting the desired properties. Among these methods, UV irradiation is preferable from the perspective of enabling patterning of alignment and, more importantly, facilitating polymerization reactions in a short time.

Furthermore, heating can also be performed during UV irradiation. The heating temperature during UV irradiation should be within the temperature range where the introduced liquid crystal will exhibit liquid crystal properties, usually above 40°C. It is better to heat at a temperature before it changes into the isotropic phase of liquid crystal.

Here, the UV irradiation wavelength should be selected to achieve the best reaction quantum yield of the polymeric compound to be reacted. The UV irradiation dose is usually 0.01 to 30 J/ ^cm² , and preferably below 10 J/ ^cm² . The lower the UV irradiation dose, the better it can suppress the reliability reduction caused by the damage to the components constituting the liquid crystal display element. Furthermore, by reducing the UV irradiation time, the manufacturing takt will be improved, which is more ideal.

Furthermore, when polymerization is carried out by heating only without UV irradiation, it is better to conduct the reaction at a temperature suitable for polymerizable compounds, and within a temperature range that does not reach the decomposition temperature of liquid crystals. Specifically, this range is 100–150°C.

When providing sufficient energy to induce polymerization of free radical polymerizable compounds, it is best to be in a field-free state where no voltage is applied.

<Liquid Crystal Display Element> Liquid crystal display elements can be manufactured using liquid crystal cells obtained in this manner. A liquid crystal display element, for example, includes: a first substrate, a second substrate disposed opposite to the first substrate, and liquid crystal filling the space between the first and second substrates. Furthermore, the liquid crystal display element is formed by polymerizing the free radical polymerizing compound in a state where a liquid crystal composition containing liquid crystal and a free radical polymerizing compound represented by formula (A) is in contact with a free radical generating film on the first substrate, which has a free radical generating film. Regarding liquid crystal display elements, for example, by conventionally providing reflective electrodes, transparent electrodes, λ/4 plates, polarizing films, color filter layers, etc., within the liquid crystal cells as needed, a reflective liquid crystal display element can be manufactured. Furthermore, by conventionally arranging backlights, polarizing plates, λ/4 plates, transparent electrodes, polarizing films, and color filter layers, transmissive liquid crystal display elements can be manufactured.

Figure 1 is a schematic cross-sectional view showing an example of a horizontal electric field liquid crystal display element of the present invention, which is an example of an IPS-mode liquid crystal display element. In the horizontal electric field liquid crystal display element 1 illustrated in Figure 1, liquid crystal 3 is sandwiched between a comb electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb electrode substrate 2 has: a substrate 2a, a plurality of linear electrodes 2b formed on the substrate 2a and arranged in a comb-like shape, and a liquid crystal alignment film 2c formed on the substrate 2a to cover the linear electrodes 2b. The counter substrate 4 has: a substrate 4b and a liquid crystal alignment film 4a formed on the substrate 4b. The liquid crystal alignment film 2c is, for example, a weakly anchored film obtained by chemically altering a free radical-generating film. The liquid crystal alignment film on the comb-shaped electrode substrate side is obtained, for example, by polymerizing the free radical polymerizing compound in a state where a liquid crystal composition containing liquid crystal and a free radical polymerizing compound is brought into contact with free radicals to form a film. In this transverse electric field liquid crystal display element 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b as shown by the power line L.

Figure 2 is a schematic cross-sectional view showing another example of the horizontal electric field liquid crystal display element of the present invention, which is an example of an FFS mode liquid crystal display element. In the horizontal electric field liquid crystal display element 1 illustrated in Figure 2, liquid crystal 3 is sandwiched between a comb electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb electrode substrate 2 has: a substrate 2d, surface electrodes 2e formed on the substrate 2d, an insulating film 2f formed on the surface electrodes 2e, a plurality of linear electrodes 2g formed on the insulating film 2f and arranged in a comb shape, and a liquid crystal alignment film 2h formed on the insulating film 2f to cover the linear electrodes 2g. The opposing substrate 4 includes a substrate 4b and a liquid crystal alignment film 4a formed on the substrate 4b. The liquid crystal alignment film 4a is, for example, a weakly anchored film obtained by chemically altering a free radical-generating film. The liquid crystal alignment film on the comb-shaped electrode substrate side is, for example, obtained by polymerizing a free radical polymerizing compound in a state where a liquid crystal composition containing liquid crystal and a free radical polymerizing compound is in contact with a free radical-generating film. In this transverse electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the linear electrode 2g, an electric field is generated between the surface electrode 2e and the linear electrode 2g as shown by the power line L. [Embodiment]

The present invention is illustrated below with specific examples, but the present invention is not limited to these examples. The abbreviations of the compounds and the methods for determining their properties are as follows.

(Diamine) DA-1 to DA-5: These are compounds represented by the formulas (DA-1) to (DA-5), respectively [Chemistry 38]

(Tetracarboxylic dianhydride) TC-1～TC-3: Compounds represented by the formulas (TC-1)～(TC-3) respectively [Chemistry 39]

(Additives) Add-1～Add-12: Compounds represented by the formulas (Add-1)～(Add-12) respectively. Add-C1～Add-C3: Compounds represented by the formulas (Add-C1)～(Add-C3) respectively. AD-1: Compound represented by the formula (AD-1) [Chemical 40] [Chemistry 41]

(Soluble) THF: Tetrahydrofuran _{; CH2Cl2} : Dichloromethane; _CHCl3 : Chloroform; NMP: N-Methyl-2-pyrrolidone; BCS: Butylceroxose; GBL: γ-Butyrolactone (Reaction Reagent); TEA: Triethylamine; DMAP: 4-Dimethylaminopyridine (Other); BHT: Dibutylhydroxytoluene

<Viscosity Measurement> The viscosity of polyacrylic acid solutions, etc., was measured using a TVE-22H type E viscometer (manufactured by Toki Sangyo Co., Ltd.) under the following conditions: sample volume 1.1 mL, tapered rotor TE-1 (1°34’, R24), and temperature 25°C.

<Determination of Molecular Weight> The molecular weight of polyimide precursors and polyimides was determined using a room temperature gel osmosis chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko Corporation) and columns (GPC KD-803, GPC KD-805) (manufactured by Showa Denko Corporation) as described below. Column temperature: 50℃ Eluent: N,N-dimethylformamide (with additives including lithium bromide monohydrate (LiBr· _H₂O ) 30 mmol/L, anhydrous phosphoric acid (o-phosphoric acid) 30 mmol/L, and tetrahydrofuran (THF) 10 mL/L) Flow rate: 1.0 mL/min Analytical line preparation Standard samples: TSK standard polyethylene oxide (molecular weight; approx. 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; approx. 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratories).

<Determination of Polyimide Ratio> 20 mg of polyimide powder was placed in an NMR sample tube (a standard NMR sampling tube, φ5, manufactured by Kusano Scientific Co., Ltd.), and 1.0 mL of dimethyl monoxide deuteride (a mixture of DMSO- _d6 and 0.05% by mass tetramethylsilane (TMS)) was added. The solution was then dissolved completely by ultrasound. The proton NMR of the solution was measured at 500 MHz using a Fourier transform superconducting nuclear magnetic resonance (FT-NMR) device, "AVANCE III" (manufactured by BRUKER). The chemiimination rate is determined using the proton from the unchanged structure before and after amide imination as the reference proton. It is calculated using the cumulative peak value of this proton and the cumulative peak value of the proton from the NH group of amide acid appearing around 9.5–10.0 ppm, according to the following formula. In the formula, x is the cumulative peak value of the proton from the NH group of amide acid, y is the cumulative peak value of the reference proton, and α is the ratio of the reference proton to the number of protons in the NH group of amide acid when it is polyamide (amide imination rate is 0%). Vamide imination rate (%) = (1 - α･x/y) × 100

<<Synthetic Examples: Synthesis of Additives for Weakly Anchoring IPS>> The products described in the following synthetic examples were identified using ^1H -NMR analysis (analytical conditions are as follows). Apparatus: Fourier transform superconducting nuclear magnetic resonance (FT-NMR) device "AVANCE III" (BRUKER) 500MHz. Solvent: _CDCl3 (deuterated chloroform) or DMSO- _d6 (deuterated dimethyl monoxide). Reference material: Tetramethylsilane (TMS) (δ 0.0 ppm for ^1H ).

<Synthetic Example 1: Synthesis of Add-1 (1-phenylhexyl methacrylate)> [Chemical Engineering 42]

In a 500 mL four-necked flask equipped with a stir bar, weigh and dissolve 1-phenyl-1-hexanol (25.0 g: 0.140 mol), TEA (21.3 _g : 0.210 mol), and _CH₂Cl₂ (300 mL). Cool the solution to 0°C using an ice bath, then slowly add methacryloyl chloride (16.1 g: 0.155 mol) dropwise while maintaining the internal temperature below 5°C. Return the solution to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution. Wash the solution three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 8/2 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-1 (29.3 g: 82% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ :7.35-7.27(5H), 6.01(1H), 5.75-5.72(1H), 5.69(1H), 1.90-1.85(3H), 1.79-1.85(2H), 1.25-1.18(6H), 0.83-0.82(3H)[ppm]

<Synthetic Example 2: Synthesis of Add-2 (1-phenylbutyl methacrylate)> [Chemical Engineering 43]

In a 500 mL four-necked flask equipped with a stir bar, weigh _and dissolve 1-phenyl-1-butanol (25.0 g: 0.166 mol), TEA (25.3 g: 0.250 mol), and _CH₂Cl₂ (300 mL). Cool the solution to 0°C using an ice bath, then slowly add methacryloyl chloride (20.8 g: 0.199 mol) dropwise while maintaining the internal temperature below 5°C. Return the solution to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution. Wash the solution three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 8/2 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-2 (31.2 g: 86% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ :7.36-7.28(5H), 6.12(1H), 5.77-5.74(1H), 5.69(1H), 1.90-1.87(3H), 1.76-1.73(2H), 1.37-1.29(2H), 0.88-0.84(3H)[ppm]

<Synthetic Example 3: Synthesis of Add-3 (1-phenylbutyl acrylate)> [Chemical Engineering 44]

In a 500 mL four-necked flask equipped with a stir bar, weigh and dissolve 1-phenyl-1-butanol (25.0 g: 0.166 mol), TEA (25.3 g: 0.250 mol), and THF (300 mL). Cool the solution to 0°C using an ice bath, then slowly add acryloxychloride (16.6 g: 0.183 mol) dropwise while maintaining the internal temperature below 5°C. Return the solution to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution. Wash the solution three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 8/2 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-3 (26.8 g: 79% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ :7.36-7.28(5H), 6.38-6.34(1H), 6.24-6.19(1H), 5.96-5.94(1H), 5.79-5.7 6(1H), 1.89-1.85(2H), 1.77-1.74(2H), 1.37-1.22(1H), 0.89-0.86(3H)[ppm]

<Synthetic Example 4: Synthesis of Add-4 (2-methyl-1-phenylpropan-2-yl methacrylate)> [Chemical Engineering 45]

In a 500 mL four-necked flask equipped with a stir bar, weigh 2-methyl-1-phenyl-2-propanol (25.0 g: 0.166 mol), TEA (33.7 g: 0.333 mol), DMAP (2.0 g: 0.017 mol), and _CHCl3 (300 mL) and dissolve them. Cool the solution to 0°C in an ice bath, then slowly add methacryloyl chloride (26.0 g: 0.249 mol), stir at 0°C for 30 minutes, and then allow the reaction to proceed at 70°C for 18 hours. After confirming the reaction completion by HPLC, ethyl acetate (200 mL) was added to the reaction solution. The precipitated salt was removed by filtration, followed by washing three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, and solvent was removed by rotary evaporation to obtain the crude product. Purification was carried out by silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)). Solvent removal and vacuum drying were performed to obtain Add-4 (21.6 g: 87% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ^¹H -NMR (500 MHz) in _CDCl₃ : 7.32–7.22 (5H), 6.02 (1H), 5.50 (1H), 3.12 (2H), 1.92 (3H), 1.52 (6H) [ppm]

<Synthetic Example 5: Synthesis of Add-5 (2-methyl-4-phenylpropan-2-yl methacrylate)> [Chemical Engineering 46]

In a 500 mL four-necked flask equipped with a stir bar, weigh 2-methyl-4-phenyl-2-butanol (25.0 g: 0.152 mol), TEA (30.8 g: 0.304 mol), DMAP (1.8 g: 0.015 mol), and _CHCl3 (300 mL) and dissolve them. Cool the solution to 0°C in an ice bath, then slowly add methacryloyl chloride (23.8 g: 0.228 mol), stir at 0°C for 30 minutes, and then allow the reaction to proceed at 70°C for 18 hours. After confirming the reaction completion by HPLC, ethyl acetate (200 mL) was added to the reaction solution. The precipitated salt was removed by filtration, followed by washing three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, and solvent was removed by rotary evaporation to obtain the crude product. Purification was carried out by silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)). Solvent removal and vacuum drying were performed to obtain Add-5 (29.0 g: 82% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ^¹H -NMR (500 MHz) in _CDCl₃ : 7.32–7.19 (5H), 6.05 (1H), 5.52 (1H), 2.71–2.68 (2H), 2.14–2.11 (2H), 1.95 (3H), 1.58 (6H) [ppm]

<Synthetic Example 6: Synthesis of Add-6 (3-ethyl-1-phenylpentan-3-yl methacrylate)> [Chemical 47]

(Step 1) Weigh methyl 3-phenylpropanoate (25.0 g: 0.152 mol) and THF (500 mL) into a 1 L four-necked flask equipped with a stir bar and dissolve them. Cool the solution to 0 °C in an ice bath, then slowly add ethylmagnesium bromide (3.0 mol/L ether solution, 107 mL: 0.320 mol), stirring at 0 °C for 30 minutes, and react at room temperature for 6 hours. After confirming the reaction is complete by HPLC, cool the flask to 0 °C again in an ice bath, ensuring the internal temperature does not exceed 10 °C, and gradually add 10% ammonium chloride aqueous solution (200 mL) for quenching. After allowing the reaction solution to settle, the supernatant was recovered by shoveling. The residue was washed with ethyl acetate, and this process was repeated several times. The combined recovered solution was washed three times with pure water (200 mL) and once with saturated brine (200 mL) using a separatory funnel. Dehydration was performed using anhydrous magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (spreading solvent: ethyl acetate/n-hexane = 5/5 (volume ratio)). Solvent extraction and vacuum drying were performed to obtain Add-6a (27.2 g: 93% yield, colorless transparent liquid). The target compound was confirmed by ^1H -NMR determination. ^1H -NMR (500MHz) in _CDCl3 : 7.29-7.16 (5H), 2.65-2.61 (2H), 1.74-1.70 (2H), 1.56-1.52 (4H), 1.15 (1H), 0.95-0.89 (6H) [ppm]

(Step 2) Weigh Add-6a (25.0 g: 0.130 mol), TEA (26.3 g: 0.260 mol), DMAP (11.6 g: 0.013 mol), and CHCl3 (300 mL) into a 500 mL four-necked flask equipped with _a stir bar and dissolve them. Cool the solution to 0°C using an ice bath, then slowly add methacryloyl chloride (20.9 g: 0.195 mol), stir at 0°C for 30 minutes, and then allow the reaction to proceed at 70°C for 18 hours. After confirming the reaction completion by HPLC, ethyl acetate (200 mL) was added to the reaction solution. The precipitated salt was removed by filtration, followed by washing three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, and solvent was removed by rotary evaporation to obtain the crude product. Purification was carried out by silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)). Solvent removal and vacuum drying were performed to obtain Add-6 (28.4 g: 84% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ^¹H -NMR (500 MHz) in _CDCl₃ : 7.28–7.16 (5H), 6.04 (1H), 5.48 (1H), 2.59–2.55 (2H), 2.17–2.13 (2H), 2.01–1.90 (4H＋3H), 0.90–0.87 (6H) [ppm]

<Synthetic Example 7: Synthesis of Add-7 (2-methyl-4-phenylbutan-2-yl acrylate)> [Chemical Engineering 48]

In a 500 mL four-necked flask equipped with a stir bar, weigh and dissolve 2-methyl-4-phenyl-2-butanol (25.0 g: 0.152 mol), TEA (23.1 g: 0.228 mol), and THF (300 mL). Cool the solution to 0°C using an ice bath, then slowly add acryloxychloride (16.5 g: 0.182 mol) dropwise while maintaining the internal temperature below 5°C. Return the solution to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution. Wash the solution three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-7 (29.9 g: 90% yield, colorless transparent liquid). Identification as the target compound was performed using ^1H -NMR. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ : 7.29-7.15(5H), 6.27-6.23(1H), 6.11-6.06(1H), 5.86-5.84(1H), 2.62-2.58(2H), 2.07-2.03(2H), 1.49(6H)[ppm]

<Synthetic Example 8: Synthesis of Add-8 (1-phenylhexan-3-yl methacrylate)> [Chemical Engineering 49]

(Step 1) Weigh and dissolve hydrocinnamaldehyde (25.0 g: 0.186 mol) and THF (300 mL) in a 500 mL four-necked flask equipped with a stir bar. Cool the solution to -78°C using a dry ice-methanol bath, then add n-propylmagnesium bromide (1.5 mol/L THF solution, 186 mL: 0.279 mol) dropwise, ensuring the internal temperature does not exceed -70°C. After the addition is complete, return to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, cool the reaction solution to 0°C, add 1 N hydrochloric acid aqueous solution (100 mL), and quench the reaction. Ethyl acetate (200 mL) was added to the reaction solution, and the solution was washed three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Further vacuum drying yielded Add-8a (30.0 g: 89% yield, colorless transparent liquid).

(Step 2) Weigh Add-8a (30.0 g: 0.168 mol), TEA (25.5 g: 0.252 mol), and THF (300 mL) into a 500 mL four-necked flask equipped with a stir bar and dissolve them. Cool the solution to 0°C using an ice bath, then slowly add methacryloyl chloride (21.1 g: 0.201 mol) dropwise while maintaining the internal temperature below 5°C. Return to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution, and wash three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-8 (35.6 g: 86% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ :7.28-7.15(5H), 6.02(1H), 5.64(1H), 4.90-4.88(1H), 2.62-2.55(2H), 1 .90-1.85(2H+3H), 1.59-1.54(2H), 1.30-1.28(2H), 0.88-0.86(3H)[ppm]

<Synthetic Example 9: Synthesis of Add-9 (5-phenylpentyl methacrylate)> [Chemical Engineering 50]

In a 500 mL four-necked flask equipped with a stir bar, weigh and dissolve 5-phenyl-1-pentanol (25.0 g: 0.152 mol), TEA (23.1 g: 0.228 mol), and THF (300 mL). Cool the solution to 0°C using an ice bath, then slowly add methacryloyl chloride (19.1 g: 0.182 mol) dropwise while maintaining the internal temperature below 5°C. Return the solution to room temperature and stir for 18 hours. After confirming the reaction is complete using HPLC, add ethyl acetate (200 mL) to the reaction solution. Wash the solution three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, followed by solvent extraction using a rotary evaporator to obtain the crude product. Purification was carried out using silicone column chromatography (spreading solvent: n-hexane/ethyl acetate = 8/2 (volume ratio)), followed by solvent extraction and vacuum drying to obtain Add-9 (31.8 g: 90% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ¹ H-NMR(500MHz) in DMSO-d ₆ : 7.28-7.14(5H), 6.00(1H), 5.64(1H), 4.08(2H), 2.59-2.56(2H), 1.87(3H), 1.67-1.57(4H), 1.38-1.32(2H)[ppm]

<Synthetic Example 10: Synthesis of Add-11 (3-methyl-1-phenylpentan-3-yl methacrylate)> [Chemical 51]

In a 500 mL four-necked flask equipped with a stir bar, weigh 3-methyl-1-phenyl-3-pentanol (25.0 g: 0.140 mol), TEA (28.4 g: 0.280 mol), DMAP (1.4 g: 0.014 mol), and _CHCl3 (300 mL) and dissolve them. Cool the solution to 0°C in an ice bath, then slowly add methacryloyl chloride (22.0 g: 0.210 mol), stir at 0°C for 30 minutes, and then allow the reaction to proceed at 70°C for 18 hours. After confirming the reaction completion by HPLC, ethyl acetate (200 mL) was added to the reaction solution. The precipitated salt was removed by filtration, followed by washing three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, and solvent was removed by rotary evaporation to obtain the crude product. Purification was carried out by silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)). Solvent removal and vacuum drying were performed to obtain Add-11 (26.6 g: 77% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ^¹H -NMR (500 MHz) in _CDCl₃ : 7.32-7.19 (5H), 6.06 (1H), 5.52 (1H), 2.68-2.62 (2H), 2.71-2.21 (1H), 2.12-2.00 (2H), 1.95 (3H), 1.92-1.86 (4H), 1.86 (3H), 0.96-0.93 (3H) [ppm]

<Synthetic Example 11: Synthesis of Add-12 (N-(3-phenylpropyl)-N-propylacrylamide)> [Chemical 52]

In a 500 mL four-necked flask equipped with a stir bar, weigh N-(3-phenylpropyl)-N-propylamine (20.0 g: 0.113 mol), TEA (22.8 g: 0.226 mol), and THF (250 mL) and dissolve them. Cool the solution to 0°C using an ice bath, then slowly add acrylonitrile chloride (12.3 g: 0.136 mol), stir for 30 minutes at 0°C, and allow the reaction to proceed at room temperature for 18 hours. After confirming the reaction completion by HPLC, ethyl acetate (200 mL) was added to the reaction solution. The precipitated salt was removed by filtration, followed by washing three times with 10% potassium carbonate aqueous solution (100 mL) and three times with pure water (100 mL) using a separatory funnel. After washing, dehydration was performed using magnesium sulfate, and solvent was removed by rotary evaporation to obtain the crude product. Purification was carried out by silicone column chromatography (developing solvent: n-hexane/ethyl acetate = 9/1 (volume ratio)). Solvent removal and vacuum drying were performed to obtain Add-12 (18.2 g: 70% yield, colorless transparent liquid). ^¹H -NMR analysis confirmed it to be the target compound. BHT (equivalent to 0.01 mol%) was added as a polymerization inhibitor. ^¹H -NMR (500 MHz) in DMSO- _d₆ : 7.27–7.18 (5H), 6.74–6.66 (1H), 6.15–6.10 (1H), 5.65–5.62 (1H), 3.39–3.20 (4H), 2.55 (2H), 1.80–1.78 (2H), 1.49–1.48 (2H), 0.89–0.78 (3H) [ppm]

<<Synthesis of Polyamide and Polyimide>> <Synthesis Example 12> In a 100 mL four-necked flask equipped with a mechanical stirrer and a nitrogen inlet tube, DA-1 (1.08 g: 10.00 mmol) and DA-3 (3.30 g: 10.00 mmol) were measured, and NMP (24.9 g) was added. After dissolving the solution by stirring under nitrogen, TC-2 (2.50 g: 10.00 mmol) was added while maintaining the temperature below 10°C using an ice bath. The reaction was carried out under nitrogen at 50°C for 6 hours. After returning to room temperature, TC-1 (1.84 g: 9.40 mmol) and NMP (10.0 g) were added, and the reaction was carried out at room temperature for 18 hours to obtain a polyamide solution (PAA-1) with a viscosity of approximately 1,120 mPa·s and a solid content of 20% by mass. The polyamide has a number average molecular weight of 11,200 and a weight average molecular weight of 31,360. In a 300 mL pear-shaped flask equipped with a stir bar and a nitrogen inlet tube, measure 40.0 g of the polyacrylic acid solution (PAA-1) obtained above, add 74.3 g of NMP, and stir at room temperature for a while. Then add acetic anhydride (5.61 g: 54.98 mmol) and pyridine (2.90 g, 36.65 mmol). Stir at room temperature under nitrogen for 30 minutes, and then react at 50 °C under nitrogen for 3 hours. After the reaction is complete, slowly pour the reaction solution into methanol (500 mL) cooled to below 10 °C while stirring to precipitate the solid, and stir for 10 minutes. The precipitate was separated by filtration and washed twice with methanol (200 mL) for 30 minutes each time. The solid was then vacuum-dried at 80°C to obtain the desired polyimide powder (SPI-1) (7.04 g, yield 88%). The polyimide had an imidization rate of 57%, a number average molecular weight of 10,400, and a weight average molecular weight of 29,120.

<Synthesis Example 13> In a 100 mL four-necked flask equipped with a mechanical stirrer and a nitrogen inlet tube, DA-2 (3.42 g: 14.00 mmol) and DA-4 (4.11 g: 6.00 mmol) were measured, and NMP (56.8 g) was added. The mixture was stirred under nitrogen to dissolve the DA-2. Then, TC-3 (4.26 g: 19.00 mol) and NMP (10.0 g) were added while maintaining the temperature below 10°C using an ice bath. The reaction was carried out at room temperature for 24 hours, thereby obtaining a polyamide solution (PAA-2) with a viscosity of approximately 680 mPa·s and a solid content of 15% by mass. The molecular weight of this polyamide is: number average molecular weight: 17,200; weight average molecular weight: 48,160.

<Synthesis Example 14> In a 100 mL four-necked flask equipped with a mechanical stirrer and a nitrogen inlet tube, DA-2 (3.42 g: 14.00 mmol) and DA-5 (1.55 g: 6.00 mmol) were measured, and NMP (42.0 g) was added. The mixture was stirred under nitrogen to dissolve the DA-2. Then, TC-3 (4.21 g: 18.8 mmol) and NMP (10.0 g) were added while maintaining the temperature below 10°C using an ice bath. The reaction was carried out at room temperature for 24 hours, thereby obtaining a polyamide solution (PAA-3) with a viscosity of approximately 710 mPa·s and a solid content of 15% by mass. The molecular weight of this polyamide is: number average molecular weight: 15,500; weight average molecular weight: 41,800.

<<Preparation of Liquid Crystal Orientation Agent>> <Preparation Example 1: Preparation of Free Radical Film-Generating Composition AL-1> In a 50 mL Erlenmeyer flask equipped with a stir bar, 2.0 g of polyimide powder (SPI-1) obtained in Synthesis Example 12 above was measured, and NMP (18.0 g) was added. The mixture was stirred at room temperature for 12 hours to dissolve. After confirming that the solid was completely dissolved, NMP (8.0 g), BCS (12.0 g), and AD-1 (0.20 g) were added, and the mixture was stirred at room temperature for 1 hour, thereby obtaining the liquid crystal orientation agent and free radical film-generating composition (AL-1) used in this invention.

<Preparation Example 2: Preparation of Free Radical Film-Forming Component AL-2> In a 50 mL Erlenmeyer flask equipped with a stir bar, 15.0 g of the polyacrylic acid solution (PAA-2) obtained in Synthesis Example 13 above was measured, and NMP (16.5 g) and BCS (13.5 g) were added. The mixture was stirred at room temperature for 1 hour to obtain the liquid crystal alignment agent and free radical film-forming component (AL-2) used in this invention.

<Preparation Example 3: Preparation of Liquid Crystal Orientation Agent AL-3> In a 50 mL Erlenmeyer flask equipped with a stir bar, 15.0 g of the polyacrylic acid solution (PAA-3) obtained in Synthesis Example 14 above was measured, and NMP (16.5 g) and BCS (13.5 g) were added. The mixture was stirred at room temperature for 1 hour to obtain the liquid crystal orientation agent (AL-3) used in this invention.

<Examples 1-24, Comparative Examples 1-8><Fabrication of Liquid Crystal Display Element> The following shows a method for fabricating a liquid crystal cell used to evaluate the alignment and electro-optic response of liquid crystals. First, a substrate with electrodes is prepared. The substrate is an alkali-free glass substrate with a size of 30mm × 35mm and a thickness of 0.7mm. ITO (Indium-Tin-Oxide) electrodes with an electrode width of 3μm, an electrode spacing of 6μm, and a comb-like pattern at an angle of 10° relative to the long side of the substrate are formed on the substrate to form pixels. The size of each pixel is 10mm in the longitudinal direction and approximately 5mm in the transverse direction. This is referred to as an IPS substrate. Then, the free radical generating film forming components AL-1, AL-2, liquid crystal alignment agent AL-3, and SE-6414 (manufactured by Nissan Chemical Co., Ltd.), which is a liquid crystal alignment agent for horizontal alignment, obtained by the above method, were filtered using a filter with a pore size of 1.0 μm. The resulting film was then coated and deposited using spin coating on the prepared IPS substrate and a glass substrate (hereinafter referred to as the opposing substrate) with an ITO film deposited on the back and columnar spacers with a height of 3.0 μm. After drying on a heated plate at 80°C for 80 minutes, the film was calcined at 230°C for 20 minutes to obtain a coating with a thickness of 100 nm. In the polyimide film on the IPS substrate side, alignment treatment is performed in the direction along the comb teeth, and in the polyimide film on the opposite substrate side, alignment treatment is performed in the direction orthogonal to the comb teeth electrodes. In addition, in the alignment treatment, AL-1 and SE-6414 use the friction method, with a friction device manufactured by Iinuma Gauge Manufacturing Co., Ltd., a friction cloth (YA-20R) manufactured by Yoshikawa Chemical Co., Ltd., a friction roller (diameter 10.0cm), a table conveying speed of 30mm/s, a roller speed of 700rpm, and a pushing pressure of 0.3mm. Both AL-2 and AL-3 used a UV exposure apparatus manufactured by Ushio Electric Co., Ltd., which used linearly polarized UV with an extinction ratio of approximately 26:1, with a wavelength of 254nm as the reference and an irradiation dose of 300mJ/ ^cm2 , and heated at 230°C for 20 minutes to perform alignment treatment. Subsequently, using the two substrates described above, regarding the display element as the object of the embodiment and some display elements as the comparison objects (Comparative Examples 2, 3, 4, 6, 7, 8), a display element made by combining a free radical generating alignment film AL-1 or AL-2 disposed on the IPS substrate side and a liquid crystal alignment film SE-6414 or AL-3 disposed on the opposing substrate side was used. In some display elements as the comparison objects (Comparative Examples 1 and 5), both substrates utilized SE-6414 or AL-3. The substrates were combined in a parallel manner with their respective alignment directions, the liquid crystal injection port was retained, and the surrounding area was sealed, creating an empty cell with an intercellular gap of approximately 3.0 μm. In this empty cell, liquid crystal mixtures (Add-1) to (Add-12) obtained in the above-described synthesis example with 2% by mass added, and liquid crystal mixtures without additives or liquid crystal mixtures (Add-C1) to (Add-C3) with 2% by mass added as a comparison, were vacuum-implanted at room temperature, and the injection port was sealed to form antiparallel aligned liquid crystal cells. Furthermore, the liquid crystal mixture used was LC-A (manufactured by DIC Corporation, Δn: 0.130, Δε: 4.4), and Add-10, Add-C1 to Add-C3 were purchased from Tokyo Kasei Corporation. The obtained liquid crystal cells constitute an IPS-mode liquid crystal display element. The obtained liquid crystal cells were then heated at 120°C for 10 minutes and irradiated with UV light (UV lamp: FLR40SUV32/A-1) for 30 minutes without voltage application to obtain the liquid crystal display element.

<Evaluation of Liquid Crystal Orientation> Using a polarizing microscope, the polarizing plate is set to crossed nicols, and the liquid crystal cell brightness is fixed at its minimum. From this state, the liquid crystal cell is rotated 1°, and the alignment state of the liquid crystal is observed. When no misalignment, microdomains, or other misalignment is observed, or is very slight, it is defined as "good"; when it is clearly observed, it is defined as "bad". Furthermore, a photodiode is mounted on the polarizing microscope, and an electrometer is connected via a current-to-voltage converter amplifier. The voltage under the condition of minimum brightness is monitored under crossed nicols, thereby measuring the black level (V: a.u.).

<Measurement of V-T Curve, Driving Threshold Voltage, Maximum Brightness Voltage, and Transmittance Evaluation> A white LED backlight and a luminance meter are aligned along their optical axes. Between them, a liquid crystal cell (liquid crystal display element) with a polarizing plate is positioned at its minimum brightness. Voltages are applied in 1V intervals up to 8V, and the brightness at each voltage is measured, thereby determining the V-T curve. The voltage at which the brightness reaches its maximum (Vmax) is estimated from the obtained V-T curve. Furthermore, assuming the transmitted brightness is 100% when the liquid crystal cell with no applied voltage is separated by a parallel-polarized (parallel-nico) light source, this is compared to the maximum transmitted brightness on the V-T curve to estimate the maximum transmittance (Tmax).

<Measurement of Response Time (Ton, Toff)> Using the apparatus used in the V-T curve measurement described above, connect the luminance meter to an oscilloscope to measure the response speed (Ton) when the voltage at maximum brightness is applied and the response speed (Toff) when the voltage returns to 0V.

<Voltage Retention Rate (VHR) Measurement> Voltage retention rate was measured at room temperature. A 4V voltage was applied to the fabricated liquid crystal display element at 23°C for 60μs, and the voltage was measured after 16.7ms. The voltage retention rate was calculated based on this measured value. Voltage retention rate was also measured at high temperature. A 1V voltage was applied to the fabricated liquid crystal display element at 70°C for 60μs, and the voltage was measured after 1667ms. The voltage retention rate was calculated based on this measured value. Furthermore, the voltage retention rate was measured using a VHR-1 voltage retention rate measuring device manufactured by TOYO Corporation.

<Polymer Contents> The compositions of the polymers synthesized in Synthetic Examples 11 to 13 are shown in Table 1.

[Table 1]

<Contents of Liquid Crystal Alignment Agent or Free Radical Generating Film Forming Compositions> The compositions of the liquid crystal alignment agent or free radical generating film forming compositions prepared in Preparation Examples 1 to 3 are shown in Table 2. [Table 2]

<Liquid Crystal Cell Contents (Torsion)> Table 3 shows examples and comparative examples of liquid crystal cells aligned using the torsion method.

[Table 3]

<Characteristic Evaluation Results> The characteristic evaluation results of liquid crystal cells aligned using the rubbing method are shown in Tables 4-1 and 4-2.

[Table 4-1]

[Table 4-2]

It can be seen that in the weakly anchored liquid crystal cells using the free radical polymerizable compounds (Add-1) to (Add-12) of the present invention as additives, the alignment state and black brightness are good. Compared with the strongly anchored liquid crystal cells of Comparative Example 1, Vmax is also significantly reduced, and the transmittance is significantly improved compared with Comparative Examples 1 to 3. On the other hand, in Comparative Examples 2 and 3, liquid crystal display elements using Add-C1 or Add-C2 as additives were found to have many rubbing streaks, poor black brightness, and an alignment state with increased birefringence. Furthermore, in Comparative Examples 2 and 3, compared with the strongly anchored liquid crystal cells of Comparative Example 1, it was confirmed that although Vmax was reduced, the transmittance was also reduced. This is due to the pre-tilt angle generated by the weak anchoring. In Examples 1-12, the pre-tilt angle is almost 0°, while in Comparative Example 2 it is about 72° and in Comparative Example 3 it is about 83°, resulting in a very large pre-tilt angle. On the other hand, regarding the response speed, it can be seen that the response speed of the additives used in Examples 1-12 is slightly slower than that of the strongly anchored liquid crystal cell in Comparative Example 1, but it is still within an acceptable range and achieves a fast response speed, which is also a significant improvement compared to Comparative Examples 2 and 3. In Comparative Example 4, in order to exhibit weak anchoring characteristics and show a good alignment state, the response speed is slow and the VHR is also poor. In the above embodiments and comparative examples, when Merck's MLC-3019 (Δn: 0.104, Δε: 9.9) was used instead of LC-A, good weak anchoring IPS characteristics could be obtained even when using Add-C1 and Add-C2 used in Comparative Examples 2 to 3. However, if a liquid crystal with a large Δn and a small Δε, like LC-A, was used, good weak anchoring IPS characteristics could not be obtained. This means that when manufacturing liquid crystal display elements, for example, by reducing the intercellular gap (e.g., to 3.5 μm or less), the additives used in Comparative Examples 2 and 3 cannot be adequately addressed. The additive of the present invention can obtain good weak anchoring IPS characteristics even when using liquid crystals with such large Δn and small Δε, and the response speed can be improved by narrowing the intercellular gap. Furthermore, the VHR is higher than that of Comparative Examples 1-4, especially at high temperatures, indicating that the reliability can be improved by using the additive of this invention.

<Liquid Crystal Cell Contents (Optical Alignment)> Table 5 shows examples and comparative examples of liquid crystal cells that have undergone alignment treatment using the optical alignment method.

[Table 5]

<Characteristic Evaluation Results> The characteristic evaluation results of liquid crystal cells aligned using the photoalignment method are shown in Table 6.

[Table 6]

In the weakly anchored IPS fabricated using the photoalignment method, when the free radical polymerizable compounds (Add-1) to (Add-12) of this invention were used as additives, it was confirmed that the same good properties as those obtained by the rubbing method were obtained. On the other hand, when (Add-C1) and (Add-C2) used in Comparative Examples 2 and 3 were used, micro-domains were generated, making the IPS undriveable. Unlike the rubbing method, photoalignment does not generate anisotropy of the pre-tilt angle. Therefore, it is speculated that when a larger pre-tilt angle is generated by a certain method, the direction of the pre-tilt angle is not specific, and it will become a micro-domain. If it is to be driven, the micro-domain will expand due to the electric field, thus making it undriveable. Comparative Example 8 shows the same result as the one using the triboelectric method, with the difference in response speed and VHR. It is evident that using the additive of this invention, even with photoalignment, does not generate microdomains, resulting in excellent weakly anchored IPS characteristics, making it very useful. Regarding VHR, it is also consistent with the triboelectric method, exhibiting good VHR at high temperatures. Using the free radical polymerizable compound of this invention as an additive for weakly anchored IPS has proven effective in improving reliability.

<Preparation Example 4: Preparation of Liquid Crystal Alignment Agent AL-4> In a 50 mL Erlenmeyer flask equipped with a stir bar, 10.0 g each of the free radical generating film-forming composition AL-2 prepared in Preparation Example 2 and the liquid crystal alignment agent AL-3 prepared in Preparation Example 3 were measured and stirred at room temperature for 1 hour to obtain the free radical generating film-forming composition (AL-4).

<Examples 25-36, Comparative Examples 9, 10> The liquid crystal alignment agent or free radical generating film forming composition coated on the IPS substrate and the opposing substrate in Example 1 is changed to the liquid crystal alignment agent or free radical generating film forming composition listed in Table 7 below. Furthermore, the additives listed in Table 7 are used as additives for the liquid crystal mixture. Otherwise, the process is the same as in Example 1 to fabricate liquid crystal cells and liquid crystal display elements.

<Liquid Crystal Cell Contents> Examples and comparative examples of liquid crystal cells aligned using a rubbing method are Examples 25-28 and Comparative Example 9. Examples and comparative examples of liquid crystal cells aligned using a photoalignment method are Examples 29-36 and Comparative Example 10.

[Table 7]

<Characteristic Evaluation Results> The characteristic evaluation results are shown in Table 8. [Table 8]

Regarding Examples 25-36, the content pertains to liquid crystal cells in which a free radical generating film forming composition is coated on a counter substrate and a liquid crystal alignment film is used on an IPS substrate. Examples 25-28 pertain to liquid crystal display elements manufactured using a triboelectric method, and Examples 29-36 pertain to liquid crystal display elements manufactured using a photoalignment method. Among Examples 29-36, Examples 33-36 pertain to the use of AL-4, obtained by mixing a free radical generating film forming composition with a strongly anchoring liquid crystal alignment agent, on a counter substrate. In Examples 25-36, compared to those obtained by coating a radical-generating film composition on an IPS substrate (e.g., Examples 1 and 13), there is a tendency for a slightly higher Vmax voltage. However, compared to the conventional strongly anchored liquid crystal cells shown in Comparative Examples 9 and 10, this is sufficiently low, resulting in very high transmittance. Regarding the response speed, it is evident that the difference between Ton and Toff is smaller compared to those obtained by coating a radical-generating film composition on an IPS substrate as shown in the aforementioned examples. Furthermore, it is evident that by using AL-4, obtained by mixing a radical-generating film composition with a strongly anchored liquid crystal alignment agent, a fast response speed can be obtained while maintaining high transmittance. [Industrial Applicability]

According to the present invention, a transverse electric field liquid crystal display element can be provided that, even when using liquid crystals with high Δn and low Δε, no pre-tilt angle or micro-field is generated, achieving high backlight transmittance and fast response speed, and also providing a liquid crystal display element with good reliability. Therefore, the liquid crystal display element obtained by the method of the present invention is useful as a liquid crystal display element driven by a transverse electric field.

1: Horizontal electric field liquid crystal display element 2: Comb electrode substrate 2a: Substrate 2b: Linear electrode 2c: Liquid crystal alignment film 2d: Substrate 2e: Surface electrode 2f: Insulating film 2g: Linear electrode 2h: Liquid crystal alignment film 3: Liquid crystal 4: Opposing substrate 4a: Liquid crystal alignment film 4b: Substrate L: Power lines

[Figure 1] is a schematic cross-sectional view showing one example of the horizontal electric field liquid crystal display element of the present invention. [Figure 2] is a schematic cross-sectional view showing another example of the horizontal electric field liquid crystal display element of the present invention.

Claims (19)

A method for manufacturing a liquid crystal display element includes the following steps: in a state where a liquid crystal composition containing liquid crystal and a free radical polymerizable compound represented by formula (A) is in contact with a free radical generating film, the free radical polymerizable compound undergoes a polymerization reaction; and includes the following steps: preparing a first substrate having the free radical generating film and a second substrate that is a substrate without the free radical generating film; arranging the first substrate and the second substrate facing each other with the free radical generating film in the first substrate facing the second substrate; filling the liquid crystal composition between the first substrate and the second substrate; and performing the polymerization reaction. In formula (A), M represents a polymerizable group selected from the following structures that can undergo free radical polymerization; _R1 to _R3 each independently represent a single bond, or an alkyl group with 1 to 6 carbon atoms that can also insert a bonding group; Ar represents an aromatic hydrocarbon that can also have substituents; _X1 and _X2 each independently represent a hydrogen atom, or an aromatic hydrocarbon that can also have substituents _{; R1X1} and _{R2X2 ,} together with the carbon atoms bonded to _{R1X1 and R2X2 ,} can also form a ring; however, the total number _of carbon atoms of _R1X1 , _R2X2 and _R3 is ₁ or more. In the formula, * indicates the bonding site; ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms; E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds; ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms; ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. The manufacturing method of the liquid crystal display element of claim 1, wherein in the aforementioned formula (A), _R3 is a linear alkyl group having 1 to 6 carbon atoms, and _X1 and _X2 are hydrogen atoms. The manufacturing method of the liquid crystal display element as described in claim 1, wherein the free radical generating film is a free radical generating film subjected to uniaxial alignment treatment. The method for manufacturing a liquid crystal display element, as claimed in claim 1, wherein the polymerization reaction step is performed under conditions without an electric field. The manufacturing method of the liquid crystal display element as described in claim 1, wherein the free radical generating film is a film formed by immobilizing organic groups that induce free radical polymerization. The method for manufacturing a liquid crystal display element as claimed in claim 1, wherein the free radical generating film is obtained by coating and curing a composition containing a compound and a polymer having free radical generating organic groups to form a film, thereby immobilizing the free radical generating organic groups in the film. The method for manufacturing a liquid crystal display element as described in claim 1, wherein the free radical generating film is composed of a polymer containing organic groups that induce free radical polymerization. As in the method of manufacturing a liquid crystal display element of claim 7, the polymer containing an organic group that induces free radical polymerization is selected from at least one polymer selected from polyimide precursors, polyimides, polyureas, and polyamides obtained by using a diamine component containing a diamine containing an organic group that induces free radical polymerization. As in the method for manufacturing a liquid crystal display element according to claim 8, the organic group for inducing free radical polymerization is an organic group represented by the following formula [X-1] to [X-18], [W], [Y], or [Z]; In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. However, in the alkyl group having 1 to 10 carbon atoms, the _-CH2- group of the alkyl group having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group of the alkyl group is replaced by an oxygen atom, the oxygen atom is not directly bonded to _S2 or N. _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. In formulas [W], [Y], and [Z], * indicates the bonding site; Ar represents an aromatic hydrocarbon selected from the group consisting of pentenyl, pentenyl-naphthyl, and pentenyl-biphenyl, which may also have organic groups and/or halogen atoms as substituents; ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms; when ^R9 and ^R10 are alkyl groups, they may also be terminally bonded to each other to form a ring structure; Q represents any of the following structures; In the formula, R ¹¹ represents -CH ₂ -, -NR -, -O -, or -S -, and each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; * represents a bonding site; S ³ represents a single bond, -O -, -NR -, or -S -, except that R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms; R ¹² represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. As in the method of manufacturing a liquid crystal display element of claim 8, the diamine containing an organic group that induces free radical polymerization is a diamine having a structure represented by the following formula (6), the following formula (7), or the following formula (7'); In formula (6), ^R6 represents a single bond, _-CH2- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N(CH3)-, -CON( _{CH3 )} -, or -N( _CH3 )CO-, and ^R7 represents a single bond, or _an unsubstituted or fluorine-substituted alkyl group having 1 to 20 carbon atoms. Any one or more of _-CH2- or _-CF2- in the alkyl group can also be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. In addition, any of the following groups, namely -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, can be replaced by such groups on the condition that they are not adjacent to each other; R ⁸ represents a radical polymerization reactive group selected from the following formulas [X-1] to [X-18]; In formulas [X-1] to [X-18], * indicates a bonding site, _S1 and _S2 each independently represent -O-, -NR-, or -S-, R represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. However, in the alkyl group having 1 to 10 carbon atoms, the _-CH2- group of the alkyl group having 2 to 10 carbon atoms can also be replaced by an oxygen atom. However, in _S2R or NR, when the _-CH2- group of the alkyl group is replaced by an oxygen atom, the oxygen atom is not directly bonded to _S2 or N. _R1 and _R2 each independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms. In formulas (7) and (7'), ^T1 and ^T2 are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH2O-, -N( _CH3 )-, -CON( _CH3 )-, or -N( _CH3 )CO-, and _S represents a single bond, or an unsubstituted or fluorine-substituted alkyl group with 1 to 20 carbon atoms, wherein any _-CH2- or _-CF2- of the alkyl group. One or more of these can be independently replaced by a group selected from -CH=CH-, a divalent carbon ring, and a divalent heterocyclic ring. Alternatively, they can be replaced by any of the following groups: -O-, -COO-, -OCO-, -NHCO-, -CONH-, or -NH-, provided they are not adjacent to each other; E is a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , _-SO2- , -O-( _CH2 ) _m -O-, -OC( _CH3 ) _2- , -CO-(CH2) _m- , -NH-( _CH2 ) _m- , _-SO2- ( _CH2 ) _m- , -CONH-( _CH2 ) _m- , -CONH-( _{CH2 ) m-.} -NHCO- or -COO-(CH ₂ ) _m -OCO-, where m is an integer from 1 to 8, and J is an organic radical selected from the following formulas [W], [Y] and [Z]; In formulas [W], [Y], and [Z], * indicates the bonding site with ^T2 , Ar indicates an aromatic hydrocarbon selected from the group consisting of phenyl, naphthyl, and biphenyl, which may also have organic groups and/or halogen atoms as substituents, ^R9 and ^R10 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms, and Q indicates any of the following structures; In the formula, R ¹¹ represents -CH ₂ -, -NR -, -O -, or -S -, each R independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and * represents a bonding site; S ³ represents a single bond, -O -, -NR -, or -S -, except that R represents a hydrogen atom or an alkyl group having 1 to 14 carbon atoms; R ¹² represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms; in formula (7'), each q is 0 or 1 independently, at least one q is 1, and p represents an integer from 1 to 2. The manufacturing method of the liquid crystal display element of claim 1, wherein the second substrate is a substrate coated with a liquid crystal alignment film having uniaxial alignment. The manufacturing method of the liquid crystal display element as described in claim 1, wherein the liquid crystal alignment film having uniaxial alignment is a liquid crystal alignment film for horizontal alignment. The method for manufacturing a liquid crystal display element as claimed in claim 1, wherein either the first substrate or the second substrate is a substrate having comb electrodes. A liquid crystal composition characterized by containing a liquid crystal and a free radical polymerizable compound represented by the following formula (A); In formula (A), M represents a polymerizable group selected from the following structures that can undergo free radical polymerization; _R1 to _R3 each independently represent a single bond, or an alkyl group with 1 to 6 carbon atoms that can also insert a bonding group; Ar represents an aromatic hydrocarbon that can also have substituents; _X1 and _X2 each independently represent a hydrogen atom, or an aromatic hydrocarbon that can also have substituents _{; R1X1} and _{R2X2 ,} together with the carbon atoms bonded to _{R1X1 and R2X2 ,} can also form a ring; however, the total number _of carbon atoms of _R1X1 , _R2X2 and _R3 is ₁ or more. In the formula, * indicates the bonding site; ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms; E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds; ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms; ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. As in claim 14, the liquid crystal composition, wherein in the aforementioned formula (A), _R3 is a linear alkyl group having 1 to 6 carbon atoms, and _X1 and _X2 are hydrogen atoms. A liquid crystal display element is characterized by: a first substrate having a free radical generating film, a second substrate disposed opposite to the first substrate and coated with a liquid crystal alignment film having uniaxial alignment, and liquid crystal filling the space between the first substrate and the second substrate; wherein a liquid crystal composition containing the liquid crystal and a free radical polymerizable compound represented by formula (A) is brought into contact with the free radical generating film of the first substrate having the free radical generating film, and the free radical polymerizable compound is subjected to a polymerization reaction to form the element. In formula (A), M represents a polymerizable group selected from the following structures that can undergo free radical polymerization; _R1 to _R3 each independently represent a single bond, or an alkyl group with 1 to 6 carbon atoms that can also insert a bonding group; Ar represents an aromatic hydrocarbon that can also have substituents; _X1 and _X2 each independently represent a hydrogen atom, or an aromatic hydrocarbon that can also have substituents _{; R1X1} and _{R2X2 ,} together with the carbon atoms bonded to _{R1X1 and R2X2 ,} can also form a ring; however, the total number _of carbon atoms of _R1X1 , _R2X2 and _R3 is ₁ or more. In the formula, * indicates the bonding site; ^Rb represents a straight-chain alkyl group with 2 to 8 carbon atoms; E represents a bonding group selected from single bonds, -O-, ^-NRc- , -S-, ester bonds, and amide bonds; ^Rc represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms; ^Rd represents a hydrogen atom or an alkyl group with 1 to 6 carbon atoms. As in claim 16, the liquid crystal display element wherein either the first substrate or the second substrate is a substrate having comb electrodes. The liquid crystal display element in claim 16 is a low-voltage driven transverse electric field liquid crystal display element. A free radical polymerizable compound is characterized by the following formula (A); In formula (A), M, _R1 , _R2 , _R3 , _X1 , _X2 , and Ar are any of the following combinations (i) and (iii) to (v): (i) M is a combination of the following structure (C), where _R1X1 is 1-pentyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a single bond, and Ar is a phenyl group; (iii) M is a combination of the following structure (C), where _R1X1 is an ethyl group, _R2X2 is an ethyl group, _R3 is a _1,2 -epenylethyl group, and Ar is a phenyl group; (iv) M is a combination of the following structure (C), where R1X1 is 1-propyl, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is a 1,2-epenylethyl group, _and Ar is a phenyl group; (v) M is a combination of the following structure (D), where _R1 is a single bond, _X1X1 is a single bond, _X2X2 is a single bond, _X2X2X2X2X3 ... ₁ is a hydrogen atom, _R2 is a single bond, _X2 is a hydrogen atom, _R3 is 1,2-ephedroxy, and Ar is a combination of phenyl groups; In structures (B), (C), and (D), * indicates a bonding location.