TWI572956B - Method for manufacturing optical anisotropic layer - Google Patents

Description

Method for manufacturing optical anisotropic layer

The present invention relates to a method of producing an optically anisotropic layer.

A stereoscopic display device capable of stereoscopically displaying an image includes an optically anisotropic layer having a plurality of optically anisotropic regions having mutually different retardation axes, that is, a patterned optical anisotropic layer. As a method for producing such a patterned optically anisotropic layer, there is known a method in which a photo-alignment polymer layer is subjected to polarized light exposure through a photomask to form a patterned alignment film, and then a liquid crystal composition is applied (see Editor-in-Chief of the Technical Information Association, "Complete Works of Optical Films and Film Technology Centered on Liquid Crystal Displays and Touch Panels", 1st Edition, Technical Information Association, Inc., September 30, 2008, p. 124-125, 4.3. 2 using patterning using a two-stage illumination of the mask).

The present invention provides the following <1> to <10>: <1> A manufacturing method which is formed of a liquid crystal composition containing a polymerizable liquid crystal compound and has a plurality of optical differences having mutually different retardation axes. A method for producing an optically anisotropic layer of a tropic region, comprising: (1) a step of forming a photo-alignment polymer layer, which is applied to a substrate by a photo-alignment polymer, and (2) a first irradiation step The first polarized light is irradiated to the photo-alignment polymer layer via a photomask to satisfy the following requirements A and B, and the necessary condition A: the photo-alignment polymer in the region irradiated by the first polarized light The absorbance of the layer satisfies the formula (i), A(b)/A(a) ≦ 0.95 (i) [in the formula (i), A(a) represents the absorbance at a wavelength of 314 nm before the first polarized light irradiation; A ( b) indicates the absorbance at a wavelength of 314 nm after the first polarized light irradiation].

Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii), Δn (550) ≧ 0.005 (ii) [in the formula (ii), Δn (550) ) indicates a birefringence at a wavelength of 550 nm, and (3) a second irradiation step of irradiating the photo-alignment polymer layer with the vibration direction and the first polarized light without passing through the mask after the irradiation of the first polarized light. Forming an alignment film different from the second polarized light, (4) applying a step of applying the liquid crystal composition to the patterned alignment film to form a coating film, and (5) an alignment step by The coating film is held in a film in which the liquid crystal component contained in the coating film is in a liquid crystal state to form a film in which the liquid crystal component is aligned, and (6) a polymerization step in which the liquid crystal component is contained in the film to be aligned. The production method of the above-mentioned <1>, wherein the photo-alignment polymer is a polymer which can form a crosslinked structure by light irradiation; <3> as described above <1> or < 2) The manufacturing method, wherein an angle between a vibration direction of the first polarized light and a vibration direction of the second polarized light It is 70 ° ~ 90 °; The method of any one of the above-mentioned <1> to <3> wherein the liquid crystal composition further contains a polymerization initiator and a solvent; <5> a display device provided with the above An optically anisotropic layer produced by the method of any one of <4>; <6> a manufacturing method comprising a liquid crystal composition containing a polymerizable liquid crystal compound and having a plurality of mutually different A method for producing an optically anisotropic layer of an optically anisotropic region and a laminated body of a substrate in the same late-axis direction, comprising: (1) a step of forming a photo-alignment polymer layer, which is a photo-alignment polymerization The object is coated on the substrate, and (2) a first irradiation step of irradiating the photo-alignment polymer layer with the first polarized light through the mask to satisfy the following requirements A and B: The absorbance of the photo-alignment polymer layer in the region irradiated by the first polarized light satisfies the formula (i), A(b)/A(a) ≦ 0.95 (i) [in the formula (i), A(a) represents the first The absorbance at a wavelength of 314 nm before the polarized light irradiation; A(b) represents the absorbance at a wavelength of 314 nm after the first polarized light irradiation].

Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii), Δn (550) ≧ 0.005 (ii) [in the formula (ii), Δn (550) ) indicates a birefringence at a wavelength of 550 nm, and (3) a second irradiation step, which is performed after the irradiation of the first polarized light, without The photo-alignment polymer layer is irradiated with a second polarized light having a vibration direction different from the first polarized light to form a patterned alignment film, and (4) a coating step of coating the liquid crystal on the patterned alignment film. a composition to form a coating film, and (5) an alignment step of forming a film of a liquid crystal component by aligning the liquid crystal component contained in the coating film in a liquid crystal state, (6) And a polymerization process of the above-mentioned liquid crystal component, wherein the photo-alignment polymer is light-irradiated by the method of the above-mentioned <6>, wherein the liquid crystal component is polymerized by the alignment film. The manufacturing method of the above-mentioned <6> or <7>, wherein the angle between the vibration direction of the first polarized light and the vibration direction of the second polarized light is 70° to 90° The manufacturing method of any one of the above-mentioned <6> to <8>, wherein the liquid crystal composition further contains a polymerization initiator and a solvent; <10> a display device provided with the above The laminate produced by the method of any one of <6> to <9>.

The first production method of the present invention is a method for producing an optically anisotropic layer comprising a liquid crystal composition containing a polymerizable liquid crystal compound and having a plurality of optically anisotropic regions having mutually different retardation axes, including : (1) a step of forming a photo-alignment polymer layer by coating a photo-alignment polymer on a substrate; (2) a first irradiation step of irradiating the photo-alignment polymer layer with the first polarized light via the photomask to satisfy the following requirements A and B: a necessary condition A: in the region of the first polarized light irradiation The absorbance of the light-aligning polymer layer satisfies the formula (i), A(b)/A(a) ≦ 0.95 (i) [in the formula (i), A(a) represents the wavelength before the first polarized light is irradiated at 314 nm. The absorbance underneath. A(b) represents the absorbance at a wavelength of 314 nm after the first polarized light irradiation].

Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii), Δn (550) ≧ 0.005 (ii) [in the formula (ii), Δn (550) ) indicates a birefringence at a wavelength of 550 nm]; (3) a second irradiation step of irradiating the photo-alignment polymer layer with the vibration direction and the first polarized light without passing through the photomask after the irradiation of the first polarized light Forming an alignment film different from the second polarized light; (4) applying a step of coating the liquid crystal composition on the patterned alignment film to form a coating film; (5) an alignment step by The coating film is held in a film in which the liquid crystal component contained in the coating film is in a liquid crystal state to form a film in which the liquid crystal component is aligned; and (6) a polymerization step of causing the liquid crystal component to be contained in the film to be aligned The polymerizable liquid crystal compound is polymerized.

Further, the second manufacturing method of the present invention includes the inclusion of polymerizable liquid crystal A method for producing a laminate of an optically anisotropic layer having a plurality of optically anisotropic regions having mutually different retardation directions and a substrate, comprising the above steps (1) to (1) 6).

The first and second manufacturing methods of the present invention will be described with reference to Figs. Fig. 1 is a view showing an example of a configuration of a photomask. Fig. 2 is a view showing an example of a patterned alignment film obtained by using the photomask shown in Fig. 1. Further, the configuration of the photomask or the pattern of the patterned alignment film is not limited to the configuration shown in Figs. 1 and 2, and may be changed depending on the pattern of the optical anisotropic layer required.

First, in the step (1), a photo-alignment polymer is applied onto a substrate to form a photo-alignment polymer layer (hereinafter sometimes referred to as formation step (1)). Then, in the step (2), the first polarized light is irradiated to the formed photo-alignment polymer layer via the photomask 1 (hereinafter sometimes referred to simply as the first irradiation step (2)). In the mask 1 , a stripe-shaped void portion (polarizing light transmitting portion) 2 is formed in the real portion (light shielding portion) 3 . By irradiating the first polarized light through the mask 1, an alignment restricting force is given to the first pattern region 12 (see FIG. 2) of the patterned alignment film 56 corresponding to the void portion 2 of the mask 1. Further, at this time, by changing the absorbance of the photo-alignment polymer layer in the first irradiation step and controlling the birefringence within a specific range, the first pattern region 12 is irradiated with the second polarized light as described below. At the same time, the alignment limiting force imparted in the first irradiation step can also be maintained.

Next, in the step (3), the photomask is removed, and the second polarized light is irradiated onto the entire surface of the photo-alignment polymer layer without using a photomask (hereinafter sometimes referred to as a second irradiation step (3)). At this time, since the first pattern region 12 is as described above, Since the alignment restricting force derived from the first polarized light is maintained, only the second pattern region 13 (see FIG. 2) of the patterned alignment film 56 which is a portion of the light-shielding portion 3 of the corresponding mask 1 which is not irradiated with the first polarized light is given. The alignment limiting force generated by the second polarized light. Thereby, the patterned alignment film 56 including the first pattern region 12 and the second pattern region 13 having mutually different retardation axis directions as shown in FIG. 2 is obtained. In addition, FIG. 2 is a patterned alignment film having two kinds of retardation axis directions, that is, a patterned alignment film having two pattern regions having different retardation axis directions, and the first irradiation step may be repeated (2). Further, a patterned alignment film having three or more types of retardation axis directions, that is, a patterned alignment film having three or more pattern regions having different retardation axis directions, is obtained.

Then, in the step (4), a liquid crystal composition is applied onto the obtained patterned alignment film 56 to form a coating film (hereinafter sometimes referred to simply as a coating step (4)); in the step (5), The liquid crystal property contained in the formed coating film is distributed (hereinafter sometimes referred to simply as the alignment step (5)); in the step (6), the polymerizable liquid crystal compound is polymerized (hereinafter sometimes referred to as a polymerization step (6) Thereby, an optically anisotropic layer is obtained. Moreover, the laminated body including the optically anisotropic layer and the substrate is obtained by the above steps (1) to (6). Thus, by controlling the physical properties of the photo-alignment polymer layer in the first irradiation step (2), no mask is required in the second irradiation step (3). Therefore, in the present invention, the number of times of use of the photomask is reduced, and thus it is easy to manufacture an optical anisotropic layer having a plurality of regions in which the directions of the slow phase axes are different, and it is possible to reduce the misalignment caused by the mask. The positional deviation of the alignment pattern. Further, even in the case where the optically anisotropic layer is produced by winding, the second pattern exposure is not required as long as the mask is used once, and thus the variation in the pattern width can be further suppressed. Further, including the obtained The stereoscopic display device of the optical anisotropic layer or the laminated body is excellent in image display.

Formation step (1)

In the forming step (1), a photo-alignment polymer is applied onto a substrate to form a photo-alignment polymer layer. The photo-alignment polymer may, for example, be a polymer having a photosensitive structure. When the polymer having a photosensitive structure is irradiated with light, the photosensitive structure of the irradiated portion is isomerized or crosslinked, whereby the photo-alignment polymer is aligned, and the liquid crystal component is aligned in a certain direction. (Orientation restriction).

Examples of the photosensitive structure include a photosensitive structure which is isomerized by light irradiation, such as an azobenzene structure, a spiropyran structure, a spirobenzopyran structure, or a fulgide structure, and a maleic acid. A photosensitive structure which is crosslinked by light irradiation, such as an imine structure, a chalcone type structure, a cinnamic acid type structure, a 1,2-vinyl structure, and a 1,2-acetylene structure. Among these, a photosensitive structure which is crosslinked by light irradiation is preferred, and a chalcone type structure (structure represented by the formula (a)) or a cinnamic acid type structure (expressed by the formula (b) is more preferable. The structure, the maleimide structure, the 1,2-vinyl structure and the 1,2-acetylene structure are further preferably a chalcone type structure and a cinnamic acid type structure. With regard to a polymer having a photosensitive structure crosslinked by light irradiation, the energy required for the reaction is small and irreversible, so that even in the case of performing multiple times of light irradiation, it can be stably maintained in the first place. The alignment limit imparted by the exposure.

[wherein, Ar independently of each other means a phenyl group, a naphthyl group or a biphenyl group. * indicates a bond].

The photo-alignment polymer may be subjected to radical polymerization of a monomer having a photosensitive structure and one or more radical polymerizable groups (preferably a vinyl group, a propylene group or a methacryl group). And a polymer obtained by polymerizing a monomer having a photosensitive structure and two or more amine groups and a dicarboxylic acid compound; and a monomer having a photosensitive structure and two or more carboxyl groups A polymer obtained by polymerization with a diamine compound; a polymer obtained by subjecting a monomer having a photosensitive structure to an anionic polymerization, a cationic polymerization or the like, a coordination polymerization or a ring-opening polymerization. Among these, a polymer obtained by radically polymerizing a monomer having a photosensitive structure and one or more radical polymerizable groups is preferred.

When the photo-alignment polymer is obtained by radically polymerizing a monomer having a photosensitive structure and one radical polymerizable group, it is preferred that the photosensitive structure and radical polymerizability are present in the monomer. The base is bonded via an alkylene group. The carbon number of the alkylene group is preferably 3 or more, more preferably 5 or more, and the carbon number of the alkylene group is preferably 20 or less, more preferably 10 or less. Further, the photosensitive structure and the radical polymerizable group may be bonded via an ester bond (-CO-O- or -O-CO-) or an ether bond (-O-).

The photo-alignment polymer may also be a copolymer obtained by polymerizing two or more kinds of monomers each having a different photosensitive structure. Further, the photo-alignment polymer may also contain a composition derived from a monomer having no photosensitive structure. Points (structural units). In this case, the content of the constituent component (structural unit) derived from the monomer having a photosensitive structure in 100 mol% of the total constituent component (structural unit) of the photo-alignment polymer is preferably 50 mol% or more. It is preferably 60 mol% or more, and more preferably 70 mol% or more. Further, in 100 mol% of the total constituent component (structural unit) of the photo-alignment polymer, the content of the constituent component (structural unit) derived from the monomer having a photosensitive structure is preferably 95 mol% or less, more preferably 90%. Mol% or less, further preferably 80 mol% or less.

The number average molecular weight of the photo-alignment polymer is preferably 20,000 or more, more preferably 25,000 or more, still more preferably 30,000 or more. Further, the number average molecular weight of the photo-alignment polymer is preferably 100,000 or less, more preferably 80,000 or less, still more preferably 50,000 or less. When the number average molecular weight is within the above range, the alignment of the liquid crystal composition becomes better when the liquid crystal composition is aligned in the alignment step (5).

Specific examples of the photo-alignment polymer include Japanese Patent No. 4,450,261, Japanese Patent No. 4011652, Japanese Patent Laid-Open No. 2010-49230, Japanese Patent No. 4404090, and Japanese Patent Laid-Open No. 2007-156439. A polymer described in JP-A-2007-232934 or the like. These photo-alignment polymers may be used singly or in combination of two or more.

The substrate is not limited, and specific examples thereof include glass, a plastic sheet, a plastic film, and a light-transmitting film. As a light transmissive film, polyethylene, polypropylene, and a drop are mentioned. Polyolefin film such as olefin polymer, polyvinyl alcohol film, polyethylene terephthalate film, polymethacrylate film, polyacrylate film, cellulose ester film, polyethylene naphthalate film, Polycarbonate film, polyfluorene film, polyether film, polyether ketone film, polyphenylene sulfide film and polyphenylene ether film. By using the substrate, the patterned alignment film or the optically anisotropic layer can be easily handled without causing cracking or the like. Further, when the optically anisotropic layer obtained by the production method of the present invention is applied to a display device, a display element substrate on which a display element is formed may be used as the substrate. That is, the patterned alignment film or the optically anisotropic layer may be directly formed on the display element substrate (the polarizing layer may be formed).

Examples of the coating method include a coating method using a coater such as a dip coater, a bar coater, or a spin coater, and an extrusion coating method, a direct gravure coating method, and a reverse gravure. Printing coating method, cap coating method, die coating method, and inkjet method.

The photo-alignment polymer is preferably dissolved in a solvent and applied to the substrate in the form of a solution. When dissolved in a solvent, the viscosity can be lowered, and the thickness of the formed layer can be reduced. The solvent is not limited, and specific examples thereof include water; alcohol solvents such as methanol, ethanol, ethylene glycol, isopropanol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, and propylene glycol monomethyl ether; Ester, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol methyl ether acetate, ethyl lactate and other ester solvents; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone a ketone solvent such as 2-heptanone or methyl isobutyl ketone; an aliphatic hydrocarbon solvent such as pentane, hexane or heptane; an aromatic hydrocarbon solvent such as toluene or xylene; a nitrile solvent such as acetonitrile; tetrahydrofuran or dimethoxy An ether solvent such as ethane or a chlorine solvent such as chloroform or chlorobenzene. These solvents may be used singly or in combination of plural kinds.

When the photo-alignment polymer is dissolved in a solvent and applied as a solution, the solvent is removed after coating and dried to form a photo-alignment polymer layer. Examples of the drying method include natural drying, air drying, and reduced pressure drying. The drying temperature is preferably 10 ° C or higher, more preferably 25 ° C or higher. Further, the drying temperature is preferably 250 ° C or lower, more preferably 200 ° C or lower. The drying time is preferably 5 seconds or longer, more preferably 10 seconds or longer. Further, the drying time is preferably 60 minutes or shorter, more preferably 30 minutes or shorter. When the drying temperature and the drying time are within the above range, the photo-alignment polymer layer can be formed without adversely affecting the substrate.

The film thickness of the photo-alignment polymer film is preferably 10 nm or more, more preferably 70 nm or more. Further, the film thickness of the photo-alignment polymer film is preferably 10000 nm or less, more preferably 1000 nm or less. If it is set to the above range, it is easy to align the liquid crystal composition to a desired angle in the subsequent step.

First illumination step (2)

In the production method of the present invention, a photo-alignment method is employed as a method of forming a patterned alignment film. The photo-alignment method is a method of imparting an alignment regulating force by polarizing irradiation (for example, linearly polarized ultraviolet ray) of a dried photo-alignment polymer layer. In the first irradiation step (2), the first polarizing light is irradiated to the photo-alignment polymer layer formed in the forming step (1) via the photomask. Thereby, the alignment regulating force can be imparted only to the region of the light-aligning polymer layer corresponding to the light-transmitting portion formed in the mask.

Examples of the photomask include those provided on an inorganic glass such as quartz glass or soda lime glass or a film such as polyester. It suffices that the portion covered with the light-shielding film shields the polarized light and the uncovered void portion transmits the polarized light. by In the presence of thermal expansion at the time of polarized light irradiation, the substrate used for the photomask is preferably a thermal expansion coefficient such as quartz glass.

As the light source of polarized light, a low-pressure mercury lamp (sterilization lamp, fluorescent chemical lamp, black light), a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a mercury xenon lamp, a xenon flash lamp, an excimer lamp, Halogen lamps, etc. The light source is not limited as long as it reacts to the photosensitive structure of the photo-alignable polymer layer. For example, a high-pressure mercury lamp or a metal halide lamp which is easily available on the market can be used.

In order to convert non-polarized light into polarized light, a method of using a Glan-Thompson or a wire grid polarizing element or a method of forming a glass plate in such a manner as to form a Brewster angle with respect to an optical axis is employed. For example, polarized light can be obtained by the method described in Japanese Patent No. 4,506,412 or Japanese Patent Laid-Open No. Hei. No. 2006-3230609.

The illuminance of the first polarized light may be a illuminance at which the photo-alignment polymer can react, and is preferably 0.01 mW/cm ² or more, more preferably 0.1 at a wavelength of 365 nm. mW/cm ² or more, further preferably 1 mW/cm ² or more. Further, when the illuminance of the first polarized light is expressed by the illuminance at a wavelength of 365 nm, it is preferably 200 mW/cm ² or less, more preferably 150 mW/cm ² or less, and further preferably 100 mW/cm. ² or less. When the illuminance is within this range, the photo-alignment polymer can be reacted, and the alignment regulating force can be effectively imparted in a short time without decomposition.

In the irradiation of the first polarized light, the cumulative amount of light changes due to the irradiation time, and therefore the irradiation time is also an important factor. In the case of exposure with the above illuminance, the amount of integrated light necessary is preferably 50 mJ/cm ² or more, more preferably 100 mJ/cm ² or more, still more preferably 200 mJ/cm ² or more, and more preferably 10,000. It is mJ/cm ² or less, more preferably 8000 mJ/cm ² or less, further preferably 5,000 mJ/cm ² or less. When the cumulative amount of light is within this range, an alignment restricting force sufficient to cause alignment of the liquid crystal composition of the subsequent step without alignment defects can be exhibited.

The maximum output wavelength of the first polarized light is preferably in the range of 300 nm to 500 nm. Further, it is preferable that the amount of light derived from light having a wavelength of 30 nm to 400 nm is 50% or more out of the amount of light emitted. The reaction of the photo-alignment polymer proceeds efficiently by using the polarization of the wavelength of the range.

The irradiation of the polarized light is preferably performed substantially perpendicularly to the plane of the photo-alignment polymer layer. Here, "the irradiation of the polarized light is performed substantially perpendicularly to the plane of the photo-alignment polymer layer" means that the polarized light is irradiated when the direction perpendicular to the plane of the photo-alignment polymer layer is defined as 90°. The irradiation with respect to the polarized light is preferably carried out in the range of 80 to 90 with respect to the plane of the photo-alignment polymer layer. The closer the irradiation angle is to 90°, the more efficiently the reaction of the photo-alignment polymer proceeds.

In the first irradiation step (2), the physical properties of the photoalignment polymer layer and the irradiation conditions of the polarized light are controlled so as to satisfy the following requirements A and B, and the photo-alignment polymer layer is irradiated through the mask. First polarized light.

Necessary condition A: The absorbance of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (i).

A(b)/A(a)≦0.95 (i) [In the formula (i), A(a) represents the absorption at a wavelength of 314 nm before the first polarized light irradiation. Luminosity. A(b) represents the absorbance at a wavelength of 314 nm after the first polarized light irradiation].

Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii).

Δn (550) ≧ 0.005 (ii) [In the formula (ii), Δn (550) represents a birefringence at a wavelength of 550 nm].

By satisfying the above-described requirements A and B, even in the second irradiation step described below, the second polarized light is irradiated to the portion having the alignment restricting force by the first polarized light in this step, and the second polarized light can be maintained. A polarizing alignment force. Further, in the case where any of the necessary conditions A and B are lacking, sufficient alignment restriction force cannot be obtained, and thus an alignment defect or the like is generated in the patterned optical anisotropic layer.

The absorbance of the photo-alignment polymer layer in the region where the first polarized light is irradiated by the necessary condition A satisfies the formula (i).

The absorbance of the photo-alignment polymer can be measured by using a spectrophotometer (for example, "Shimadzu Corporation, UV-3150" or the like) which is usually used. The value of the above A(b)/A(a) is preferably 0.9 or less, more preferably 0.7 or less. The smaller the value of A(b)/A(a) above, the better, but it is usually 0.5 or more. The value of A(b)/A(a) above can be adjusted by controlling the irradiation time of the first polarized light. If the irradiation time is extended, the value of A(b)/A(a) becomes small.

The necessary condition B is that the birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii).

The birefringence Δn(λ) is determined in the manner of the formula (X).

△n(λ)=Re(λ)/d (X) [In the formula (X), Δn(λ) represents a birefringence at a wavelength λ nm, Re (λ) represents a phase difference at a wavelength λ nm, and d represents a film thickness].

The birefringence Δn (550) in the formula (ii) can be determined by measuring the phase difference and the film thickness of the photo-alignment polymer layer as shown in the above formula (x). The phase difference value of the photo-alignment polymer layer after the first polarized light irradiation may be measured by using an ellipsometer (for example, "M-220" manufactured by JASCO Corporation). The film thickness can be measured using a laser microscope (for example, "Olympus Co., Ltd., LEXT-3000"). The above Δn (550) can be adjusted by controlling the irradiation time of the first polarized light. If the irradiation time is extended, the value of Δn (550) becomes large.

Here, since the direction of the slow phase axis in each of the optical anisotropy regions is one type, when an optical anisotropic layer having three or more optical anisotropy regions having different retardation axes is obtained, it is only necessary to repeat The first irradiation step (2) may be performed. For example, in the case of producing an optically anisotropic layer having optical anisotropy regions having different directions of three slow phase axes, the vibration direction is irradiated to the photoalignment polymer layer via the photomask after the first polarized light irradiation. The third polarized light may be different from the first polarized light and the second polarized light described below. In this case, when the first polarized light is irradiated, it is necessary to prevent the first polarized light from being irradiated by the portion (region) to which the third polarizing or the second polarized light is given the alignment restricting force, and the third polarized light must be irradiated when the third polarized light is irradiated. It is desirable to avoid illuminating the third polarized light by the portion (region) to which the second polarizing light imparts the alignment restricting force. In the case where the first irradiation step (2) is repeated, the irradiation conditions of the polarized light may be set in the same manner as the first polarized light.

Furthermore, the direction of vibration of the polarized light refers to the direction of vibration of the light wave.

Second irradiation step (3)

In the second irradiation step (3), the second alignment light having a vibration direction different from the first polarization is irradiated to the photo-alignment polymer layer irradiated with the first polarized light without passing through the mask to form a patterned alignment film. Since the vibration direction of the second polarized light is different from the vibration direction of the first polarized light, the alignment film obtained in the second irradiation step (3) becomes the region having the direction of the alignment restricting force derived from the first polarized light and has the origin A patterned alignment film in the region of the direction of the limiting force of the dipolarization.

As described above, since the first polarized light is irradiated by controlling the necessary condition A and the necessary condition B in the first irradiation step (2), even if the second polarized light is irradiated to the portion irradiated with the first polarized light, Maintain the alignment limiting force from the first polarized light. Therefore, in the manufacturing method of the present invention, it is easier to work in the second irradiation step (3) without using a photomask. Moreover, since the number of times of use of the photomask is reduced, the positional deviation of the alignment pattern due to poor alignment of the photomask can be reduced. Further, even in the case where the optically anisotropic layer is produced by winding, if the photomask is used once, the second pattern exposure is not required, and thus the variation in the pattern width can be further suppressed.

The illuminance of the second polarized light may be a illuminance at which the photoalignment polymer can react, and is preferably 0.01 mW/cm ² or more, more preferably 0.1 at a wavelength of 365 nm. mW/cm ² or more, further preferably 1 mW/cm ² or more. Further, when the illuminance of the second polarized light is expressed by the illuminance at a wavelength of 365 nm, it is preferably 200 mW/cm ² or less, more preferably 150 mW/cm ² or less, and further preferably 100 mW/cm. ² or less. When the illuminance is within this range, the photo-alignment polymer can be reacted, and the alignment regulating force can be effectively imparted in a short time without decomposition.

In the irradiation of the second polarized light, the amount of accumulated light changes due to the irradiation time, and therefore the irradiation time is also an important factor. In the case of exposure by the above illuminance, the amount of integrated light required is preferably 50 mJ/cm ² or more, more preferably 100 mJ/cm ² or more, and still more preferably 200 mJ/cm ² or more. Further, the amount of integrated light required is preferably 10000 mJ/cm ² or less, more preferably 8000 mJ/cm ² or less, still more preferably 5,000 mJ/cm ² or less. When the cumulative amount of light is within this range, it is possible to exhibit an alignment regulating force sufficient to cause the liquid crystal component in the liquid crystal composition of the subsequent step to be misaligned.

The maximum output wavelength of the second polarized light is preferably in the range of 300 nm to 500 nm. Further, it is preferable that the amount of light from the wavelength of 300 nm to 400 nm is 50% or more out of the amount of light emitted. By using polarized light of a wavelength in this range, the reaction of the photo-alignment polymer can be efficiently performed. Further, the irradiation of the second polarized light is preferably substantially perpendicular to the plane of the photo-alignment polymer layer. Here, the "irradiation of the second polarized light is substantially perpendicular to the plane of the photo-alignment polymer layer", and is the same as the irradiation of the first polarized light, and is defined as a direction perpendicular to the plane of the photo-alignment polymer layer. In the case of 90°, the irradiation of the second polarized light is performed in the range of 70° to 90°. The closer the irradiation angle is to 90°, the more efficiently the reaction of the photo-alignment polymer proceeds.

Preferably, the angle between the vibration direction of the first polarized light and the vibration direction of the second polarized light is substantially orthogonal. Here, the "angle formed by the vibration direction of the first polarized light and the vibration direction of the second polarized light" means an angle smaller than the angle formed by the vibration direction of the first polarized light and the vibration direction of the second polarized light. Again It is said that the angle between the vibration direction of the first polarization and the vibration direction of the second polarization is substantially orthogonal, which means that the angle is in the range of 70° to 90°, and the angle is preferably in the range of 85° to 90°. More preferably 90°. If the angle between the vibration direction of the first polarized light and the vibration direction of the second polarized light is substantially orthogonal, the direction of the slow phase axis of the region irradiating the first polarized light and the direction of the slow phase axis of the region irradiating the second polarized light are also Orthogonally, the obtained optical anisotropic layer or laminate can be used as a polarization conversion member for stereoscopic display.

Coating step (4)

In the coating step (4), the liquid crystal composition is applied onto the patterned alignment film formed in the second irradiation step (3) to form a coating film. The liquid crystal composition contains a polymerizable liquid crystal compound. The polymerizable liquid crystal compound is a compound having liquid crystallinity and has one or more polymerizable groups in the molecule. The polymerizable group means a group which participates in the polymerization reaction of the polymerizable liquid crystal compound. Examples of the polymerizable group include a vinyl group, a vinyloxy group, a 1-chlorovinyl group, an isopropenyl group, a 4-vinylphenyl group, an acryloxy group, a methacryloxy group, and an oxirane group. Propylene oxide based. Among them, an acryloxy group, a methacryloxy group, a vinyloxy group, an oxiranyl group, and an propylene oxide group are preferred, and an acryloxy group is more preferred.

The polymerizable liquid crystal compound preferably has two or more ring structures in its molecule, and more preferably has three or more ring structures. Examples of the ring structure include a phenyl ring (benzene ring), a cyclohexane ring, a naphthalene ring, a pyrimidine ring, a pyridine ring and a thiophene ring. Among them, a phenyl ring (benzene ring) and a cyclohexane ring are preferable. Examples of the linking group which bonds two or more ring structures include -CO-O-, -CH ₂ -CH ₂ -, -CO-S-, -CO-NH-, -CH=CH-, -N=. N- and -C≡C-, wherein -CO-O- is preferred.

Specific examples of the polymerizable liquid crystal compound include "3.8.6 mesh structure (completely crosslinked type)" of "Liquid Crystal Handbook (Edited by Liquid Crystal Handbook Compilation Committee, Maruzen (issued) on October 30, 2000)" The polymerizable group in the compound described in "6.5.1 Liquid crystal material b. Polymerizable nematic liquid crystal material", and the polymerizable liquid crystal compound disclosed in JP-A-2010-31223. A commercially available product can also be used as the polymerizable liquid crystal compound, and a specific example thereof is "Paliocolor (registered trademark) LC242" commercially available from BASF JAPAN. These polymerizable liquid crystal compounds may be used singly or in combination of plural kinds. The liquid crystal composition may also contain a liquid crystal compound having no polymerizable group.

The liquid crystal composition preferably contains a solvent. The solvent is not particularly limited as long as it dissolves the components contained in the liquid crystal composition and is inert to the polymerization reaction of the polymerizable liquid crystal compound, and specific examples thereof include methanol, ethanol, ethylene glycol, and isopropanol. , propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether, propylene glycol monomethyl ether, phenol and other alcohol solvents; ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ-butyrolactone, propylene glycol Ester acetate, ethyl lactate and other ester solvents; acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, methyl isobutyl ketone and other ketone solvents; pentane, hexane, g An aliphatic hydrocarbon solvent such as an alkane; an aromatic hydrocarbon solvent such as toluene or xylene; a nitrile solvent such as acetonitrile; an ether solvent such as tetrahydrofuran or dimethoxyethane; and a chlorine solvent such as chloroform or chlorobenzene. These solvents may be used singly or in combination of plural kinds.

Preferably, the solvent is used in an amount of 50% by mass based on 100% by mass of the liquid crystal composition. Mass %~95% by mass. In other words, the content of the solid content component (the component other than the solvent in the liquid crystal composition) in the liquid crystal composition is preferably from 5% by mass to 50% by mass. The content of the solid content component is more preferably 10% by mass or more, further preferably 15% by mass or more, and more preferably 40% by mass or less, and still more preferably 35% by mass or less. When the amount of the solid content component is 5% by mass or more, the obtained optically anisotropic layer does not become too thin, and the birefringence necessary for polarization conversion can be provided. In addition, when the amount of the solid content component is 50% by mass or less, the viscosity of the liquid crystal composition is lowered, and the film thickness of the optically anisotropic layer is less likely to be uneven. The viscosity of the liquid crystal composition is preferably 0.1 mPa from the viewpoint of coatability. Above s, again, preferably 10 mPa. Below s, more preferably 7 mPa. s below.

The liquid crystal composition preferably contains a polymerization initiator. The polymerization initiator is a thermal polymerization initiator and a photopolymerization initiator, and a photopolymerization initiator is preferred in that polymerization of the polymerizable liquid crystal compound can be carried out at a low temperature.

Examples of the photopolymerization initiator include a benzoin compound, a benzophenone compound, an alkylphenone compound, a mercaptophosphine oxide compound, and the like. Compounds, phosphonium salts and phosphonium salts. Commercially available products can also be used as the photopolymerization initiator. Specifically, Irgacure (registered trademark) 907, Irgacure 184, Irgacure 651, Irgacure 819, Irgacure 250, Irgacure 369 (all manufactured by BASF JAPAN), Seikuol (registered trademark) BZ, Seikuol Z, Seikuol BEE (all manufactured by Seiko Chemical Co., Ltd.), kayacure (registered trademark) BP100 (manufactured by Nippon Kayaku Co., Ltd.), CYRACURE (registered trademark) UVI-6992 (manufactured by Dow Chemical Co., Ltd.), Adeka Optomer SP-152 Adeka Optomer SP-170 (all manufactured by ADEKA Co., Ltd.), TAZ-A, TAZ-PP (all manufactured by DKSH JAPAN Co., Ltd.), TAZ-104 (manufactured by SANWA CHEMICAL Co., Ltd.), and the like.

The liquid crystal composition may also contain additives such as a chiral agent, a polymerization inhibitor, a photosensitizer, and a leveling agent as needed.

Examples of the chiral agent include a "Liquid Crystal Device Manual" (Chapter 3, Section 4-3, TN (Twisted Nematic), STN (Super Twisted Nematic), 199 pages. Japanese Society for the Promotion of Science, 142th Committee, 1989), Japanese Patent Laid-Open No. 2007-269640, Japanese Patent Laid-Open No. 2007-269639, Japanese Patent Laid-Open No. 2007-176870, Japanese Patent Laid-Open No. 2003-137887 The compound described in the publication of the Japanese Patent Publication No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei.

Examples of the polymerization inhibitor include hydroquinones and pyrogallols having a substituent such as an alkyl ether such as hydroquinone or a substituent having an alkyl ether or a butyl catechol. And a free radical supplement such as 2,2,6,6-tetramethyl-1-piperidinyloxy radical, thiophenol, β-naphthylamine or β-naphthol.

As the photosensitizer, there are listed: Ketone and 9-oxosulfur Wait Ketones, anthraquinones, and anthracenes having a substituent such as an alkyl ether Or red fluorene.

Examples of the leveling agent include additives for radiation hardening coatings (BYK-352, manufactured by BYK-Chemie Japan, BYK-353, BYK-361N), and coating additives (manufactured by Toray Dow Corning: SH28PA, DC11PA, ST80PA), coating additives (manufactured by Shin-Etsu Chemical Co., Ltd.: KP321, KP323, X22-161A, KF6001) or fluorine-based additives (Manufactured by DIC: F-445, F-470, F-479) .

In the case where the optically anisotropic layer obtained by the production method of the present invention is used as a polarizing layer, the liquid crystal composition may further contain a dichroic dye. The above dichroic dye is not limited and may be a dye or a pigment. The absorption wavelength of the dichroic dye is preferably from 300 nm to 700 nm in the visible light range. The dichroic dye may be used singly or in combination of a plurality of dichroic dyes such as red, green and blue. Specific examples of the dichroic dye include a quinone dichroic dye, a naphthalene dichroic dye, an azo dichroic dye, and a quinone dichroic dye. In the case of the above-described dye, it is preferred to disperse into the polymer, and it is preferred.

The amount of the dichroic dye used is preferably 50 parts by mass or less, more preferably 20 parts by mass or less, and still more preferably 10 parts by mass or less based on 100 parts by mass of the polymerizable liquid crystal compound.

The liquid crystal composition can be prepared by mixing the above polymerizable liquid crystal compound, a photopolymerization initiator, a solvent, and the like, and then stirring the obtained mixture at 60 to 90 ° C for about 0.5 to 2 hours.

Examples of the method of applying the liquid crystal composition include a coating method using a coater such as a dip coater, a bar coater, or a spin coater, an extrusion coating method, and a direct gravure coating method. Reverse gravure coating method, coating method, die coating method, ink jet method, and the like.

The formed coating film is preferably one which removes volatile components such as a solvent contained in the coating film. Drying methods include natural drying method, air drying method, and decompression drying Dry method. The drying temperature is preferably from 0 ° C to 250 ° C, more preferably from 50 ° C to 220 ° C. Further, the drying time is preferably from 10 seconds to 60 minutes, more preferably from 30 seconds to 30 minutes.

Orientation step (5)

In the alignment step (5), the coating film formed in the coating step (4) is maintained at a temperature at which the liquid crystalline component contained in the coating film is in a liquid crystal state to form a film in which the liquid crystalline component is aligned. . Further, in the above coating step (4), drying (heating) when the solvent is removed may also serve as the alignment step (5). As described above, in the patterned alignment film, there is a region having a direction from the direction of the alignment restricting force of the first polarized light and a region having a direction of the alignment restricting force derived from the second polarized light, so that the liquid crystal component is obtained by using the patterned alignment film. In the alignment, regions having mutually different retardation axis directions can be patterned.

By setting the coating film (preferably, the film from which the solvent is removed from the coating film) to a temperature at which the liquid crystal component contained in the coating film is in a liquid crystal state, the liquid crystal component contained in the coating film can be made into each optical. The single domain is aligned in the anisotropic region to impart birefringence. The liquid crystal component refers to a polymerizable liquid crystal compound contained in the liquid crystal composition and a liquid crystal compound having no polymerizable group. The temperature of the alignment is preferably 0 ° C or higher, more preferably 10 ° C or higher, further preferably 50 ° C or higher, preferably 250 ° C or lower, more preferably 150 ° C or lower, and still more preferably 120 ° C or lower.

Polymerization step (6)

In the polymerization step (6), the liquid crystalline component formed in the above-mentioned alignment step (5) is polymerized by the polymerizable liquid crystal compound contained in the film to be aligned. By the state in which the components contained in the coating film have been aligned, that is, the liquid crystal contained in the coating film The component has been polymerized in the state of the liquid crystal phase, and the patterned optical anisotropic layer can be obtained in the form of a cured film of the liquid crystal phase.

The polymerization method is not limited, and when the polymerizable liquid crystal compound is a polymerizable liquid crystal compound having a photopolymerizable group, polymerization is carried out by photopolymerization; and the polymerizable liquid crystal compound is polymerizable having a heat polymerizable group. In the case of a liquid crystal compound, polymerization is carried out by a thermal polymerization method. Here, the photopolymerizable group means a group which can be polymerized by light irradiation, or a group which can be polymerized by an active radical or an active acid which is produced by light irradiation with a polymerization initiator. The term "thermally polymerizable group" means a group which can be polymerized by the action of heat, or a group which can be polymerized by an active radical or an active acid which is produced by the action of heat by a polymerization initiator.

In the production method of the present invention, it is preferred to polymerize the polymerizable liquid crystal compound by a photopolymerization method. If the polymerization is carried out without heating to a high temperature by photopolymerization, deformation of the substrate due to heat can be prevented. Moreover, manufacturing in the industry has also become easier. Further, from the viewpoint of film formability, photopolymerization is also preferred. Examples of the light source used in the photopolymerization method include visible light, ultraviolet light, and laser light. From the viewpoint of operability, ultraviolet light (wavelength 300 nm to 420 nm) is preferred. The light irradiation can also be carried out at a temperature at which the components contained in the coating film exhibit a liquid crystal phase. At this time, an optically anisotropic layer further patterned by masking or the like can also be obtained.

The illuminance of the ultraviolet light in the photopolymerization may be an illuminance for polymerizing the polymerizable liquid crystal compound, and is preferably 0.01 mW/cm ² or more, more preferably 0.1 mW, in the case of the intensity at a wavelength of 365 nm. /cm ² or more, further preferably 1 mW/cm ² or more, preferably 400 mW/cm ² or less, more preferably 300 mW/cm ² or less, still more preferably 250 mW/cm ² or less. When the illuminance is within this range, the polymerizable liquid crystal compound can be polymerized to be aligned and immobilized.

Further, the cumulative amount of ultraviolet light at the time of photopolymerization is preferably 100 mJ/cm ² or more, more preferably 500 mJ/cm ² or more, still more preferably 1000 mJ/cm ² or more, and preferably 6000 mJ/cm ^{2 .} Hereinafter, it is more preferably 4,000 mJ/cm ² or less, further preferably 3,000 mJ/cm ² or less. When the cumulative amount of light is within this range, the liquid crystal composition can be aligned without alignment defects.

When the optically anisotropic layer obtained in the present invention functions as a retardation layer, it is preferred to adjust the phase difference value of each optical anisotropy region of the optical anisotropic layer. Specifically, when the optically anisotropic layer is formed into a λ/4 plate, Re (550) is usually set to 113 nm to 163 nm in any optical anisotropy region, preferably set to 135 nm to 140 nm, and further preferably set to 137.5 ± 0.5 nm. Further, when the optically anisotropic layer is formed into a λ/2 plate, Re (550) is usually set to 250 nm to 300 nm in any optical anisotropy region, preferably 273 nm. ~277 nm, more preferably set to 275.0 ± 0.5 nm.

The retardation value of the optically anisotropic layer can be adjusted by appropriately changing the coating amount of the liquid crystal composition or the content of the polymerizable liquid crystal compound in the liquid crystal composition. Further, the phase difference value (delay value, Re(λ)) of the obtained optical anisotropic layer is determined in the manner of the formula (Y), so that the optical anisotropy layer is adjusted in order to obtain the desired phase difference value. The film thickness d can be.

Re(λ)=d×Δn(λ) (Y) [wherein, Re(λ) represents the phase difference at the wavelength λ nm, and d represents the film thickness, Δn(λ) represents the birefringence at a wavelength λ nm].

The film thickness of the optically anisotropic layer is preferably from 0.1 μm to 10 μm, more preferably from 0.5 μm to 5 μm.

The manufacturing method of the present invention may further comprise the step of forming an antireflection layer on the optically anisotropic layer formed in the polymerization step (6). By having the antireflection layer described above, it is possible to reduce the generation of reflected light from external light, and it is also possible to suppress interference between the originally emitted light and the reflected light from the optical anisotropic layer. Further, the optically anisotropic layer can be protected by the antireflection layer.

The material constituting the antireflection layer is not limited, and may be a layer composed of at least one selected from the group consisting of a metal film, a metal oxide film, a metal fluoride film, a polymer material film, and fine particles. And a known anti-reflection (AR) film, a low-reflection (LR) film, a moth-eye anti-reflection film, and the like, and the like. As a metal, silver etc. are mentioned. Examples of the metal oxide include cerium oxide, aluminum oxide, titanium oxide, cerium oxide, cerium oxide, and zirconium oxide. Examples of the metal fluoride include calcium fluoride and magnesium fluoride. Examples of the polymer material include a decane polymer, bis(4-methylpropenylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, and 4-methyl propylene oxyphenyl-4. Polymer of '-methoxyphenyl sulfide, fluorine (meth) acrylate, fluorine-containing itaconate, fluorine-containing maleate, fluorine-containing ruthenium compound, polyvinyl alcohol resin, polyvinyl butyl A polyvinyl acetal resin such as aldehyde or polyethylene formaldehyde, a cellulose resin such as cellulose acetate butyrate, a (meth)acrylic resin such as butyl acrylate, a urethane resin, a polyester resin, or an epoxy resin. Examples of the fine particles include barium sulfate, talc, kaolin, calcium sulfate, and silicone. Inorganic fine particles such as tantalum containing metal microparticles; polymethacrylic acid-methyl acrylate resin microparticles, acrylic-styrene resin microparticles, polymethyl methacrylate resin microparticles, enamel resin microparticles, polystyrene resin microparticles, polycarbonate resin Organic particles such as microparticles, benzoguanamine resin microparticles, melamine resin microparticles, polyolefin resin microparticles, polyester resin microparticles, polyamido resin microparticles, polyamidene resin microparticles, or polyvinyl fluoride resin microparticles; Japanese Patent Laid-Open 2010 Hollow organic-inorganic hybrid fine particles described in Japanese Patent Publication No. 84-418.

The antireflection layer may be a single layer or a multilayer of two or more layers. The thickness of each layer in the case of the thickness of the antireflection layer or in the case of a plurality of layers may be appropriately selected depending on the number of layers, the refractive index of the substance used for each layer, and the like. The antireflection layer can be formed by a method of applying a solution containing the above material onto an optically anisotropic layer or a method of bonding a film having a layer formed of the above material to an optically anisotropic layer. As a method of forming the above-mentioned anti-reflection layer, Japanese Patent Laid-Open No. 2003-114302, Japanese Patent Laid-Open No. Hei 7-56002, Japanese Patent No. 4190337, Japanese Patent No. 4259957, Japanese Patent No. 4032771, Japan The method described in Japanese Laid-Open Patent Publication No. 2010-122599.

The manufacturing method of the present invention may further comprise the step of forming a known antifouling layer, an antistatic layer and/or a hard coat layer as needed on the light exit side of the antireflection layer. Further, the step of peeling off the optically anisotropic layer and the patterned alignment film from the substrate of the obtained laminate may be included. Further, in addition to the step of peeling off from the substrate, a step of peeling the optically anisotropic layer from the patterned alignment film may be further included. Moreover, it may also be included in an optical anisotropic layer formed on a substrate The step of adhering another substrate and transferring the optically anisotropic layer on the other substrate.

Display device

The present invention also includes a display device including the optically anisotropic layer or the laminate obtained in the above steps. Examples of the display device include a liquid crystal display device, an organic electroluminescence (EL) display device, a plasma display device, a field emission display device (FED), and a display device having a surface conduction electron-emitting device ( SED, Surface-conduction Electron-emitter Display), electronic paper, etc.

Examples of the use of the optically anisotropic layer in the display device include a polarizing layer and a retardation layer. For example, when a liquid crystal composition forming an optically anisotropic layer contains a dichroic dye, the optically anisotropic layer functions as a polarizing layer and can be used as a substitute for a polarizing plate. Moreover, when adjusting the anisotropy of the liquid crystal component in the optical anisotropic layer, it can function as a phase difference layer, and can be applied to various display apparatuses as described below.

3 and 4 are schematic cross-sectional views showing a liquid crystal display device as an example of the liquid crystal display device of the present invention. The liquid crystal display devices 51A and 51B include a backlight device 52 as a surface light source for emitting natural light, a polarizing plate 53 having a transmission axis (not shown) in a specific direction of the plate surface, and a display element substrate 54 on which a liquid crystal display element is formed. The polarizing layer 55, the patterned alignment film 56, and the retardation layer 57. In the liquid crystal display device 51B shown in FIG. 4, an anti-reflection layer 58 is formed on the light outgoing side of the phase difference layer 57. Such liquid crystal display devices In 51A and 51B, the patterned alignment film and the optically anisotropic layer obtained by the production method of the present invention are provided as the patterned alignment film 56 and the retardation layer 57.

The display substrate 54 on which the liquid crystal display element is formed is filled with a low molecular liquid crystal composition as a display medium between the two substrates. A black matrix, a color filter, a counter electrode, a photo spacer, an alignment film, and the like are provided on one of the two substrates, and a liquid crystal driving electrode, a wiring pattern, a thin film transistor, and an alignment are provided on the other substrate. Membrane and the like. Examples of the liquid crystal display device include a transmissive type, a reflective type, and a semi-transmissive type. The operation mode of the liquid crystal cell is not particularly limited, and may be Twisted Nematic, Vertical Alignment, OCB (Optically Compensated Bend), IPS (In-Plane Swiching), etc. Any of them. As shown in FIG. 5, the display element substrate 54 has a plurality of rectangular pixels A1, A2, ...; B1, B2, ... arranged in a matrix along the main surface 50.

The polarizing layer 55 has a transmission axis 70a in a specific direction of the main surface 50 (as shown schematically in FIG. 5, an angle of inclination of 45 degrees with respect to the horizontal direction). Further, the retardation layer 57 has two phase difference regions (optical anisotropic regions): a phase difference region having a slow phase axis 71a along the principal surface 50 and having a direction different from the direction of the transmission axis 70a (optical anisotropy) The region 71A and the phase difference region (optical anisotropic region) 71B having the slow axis 71b along the principal surface 50 and having a direction different from the direction of the transmission axis 70a and the slow axis 71a.

The function of the phase difference layer 57 in the liquid crystal display devices 51A and 51B will be described with reference to Fig. 5 . Figure 5 is a diagram showing the function of a phase difference layer (optical anisotropic layer) Pattern diagram. In FIG. 5, only the display element substrate 54, the polarizing plate 55, and the retardation layer 57 are shown, and the optical alignment film 56 and the like are omitted. As shown in FIG. 5, the slow phase axis 71a of the phase difference region 71A faces the vertical direction, and the retardation axis 71b of the phase difference region 71B faces the horizontal direction. That is, when viewed from the light exit side F, with respect to the direction of the transmission axis 70a of the polarizing layer 55 (which is set to 0 degree), the retardation axis 71a of the phase difference region 71A forms an angle of 45 degrees with the direction of the transmission axis 70a. The retardation axis 71b of the phase difference region 71B forms an angle of 135 degrees with the direction of the transmission axis 70a.

With this arrangement, the phase difference regions 71A and 71B convert the linearly polarized light from the polarizing layer 55 into circularly polarized lights that are mutually inverted, and are respectively emitted toward the light emitting side F. In this example, the polarizing layer 55 is used to form the left-handed circularly polarized light by the light of the phase difference region 71A, and the polarizing layer 55 is used to form the right-handed circularly polarized light by the phase difference region 71B. Therefore, the observer can use glasses (not shown) each having a circular polarizing plate that converts right-handed circularly polarized light into linearly polarized light and a circularly polarizing plate that converts left-handed circularly polarized light into linearly polarized light. An image emitted from the above display device is observed in the form of a stereoscopic image. Thus, by using a phase difference layer 57 (optical anisotropic layer) having a plurality of phase difference regions (optical anisotropic regions) 71A, 71B having mutually different retardation axis directions, a stereoscopic display can be provided. Image display device.

FIG. 6 and FIG. 7 are schematic cross-sectional views showing a display device other than the liquid crystal display device as an example of the liquid crystal display device of the present invention. Examples of the display devices 61A and 61B other than the liquid crystal display device include an organic EL display device, a plasma display device, and a field emission display device, and have a surface conduction type. A display device for an electron emitting element, electronic paper, or the like. The display devices 61A and 61B include a display element substrate 62 on which display elements (a plurality of pixels are arranged), a polarizing layer 63, a patterned alignment film 64, and a retardation layer 65. In the display device 61B shown in FIG. 7, an anti-reflection layer 66 is formed on the light outgoing side of the phase difference layer 65. The display devices 61A and 61B include the patterned alignment film and the optically anisotropic layer obtained by the method of the present invention as the patterned alignment film 64 and the retardation layer 65, and can be displayed in the same manner as the liquid crystal display devices 51A and 51B. Stereo image.

In the case where the display device is an organic EL display device, a display element substrate on which an organic EL display element is formed is used as the display element substrate 62. The display element substrate can be produced by first depositing an organic film such as an anode or a light-emitting layer and a cathode on a glass substrate having a transparent electrode by vapor deposition to form an organic EL element and a wiring pattern, and secondarily, for example, A metal cover (protective plate) formed of SUS or Al or the like covers each of the organic EL elements laminated on the transparent electrode glass, and is then adhered to the transparent electrode glass by an adhesive; finally, each organic EL element is divided. Transparent electrode glass. As a method of manufacturing a display element substrate on which an organic EL display element is formed, for example, a method described in Japanese Patent No. 3626728 can be cited.

In the case where the above display device is a plasma display, a display element substrate on which a plasma display element is formed is used as the display element substrate 62. The display element substrate is composed of a front plate including a glass substrate in which a scanning electrode and a sustain electrode for performing surface discharge are arranged, and a back plate including a glass substrate in which the data electrodes are arranged. The scan electrode and the sustain electrode and the data electrode are formed in a matrix and form a discharge space in the gap. Line-to-ground configuration. The outer peripheral portion is sealed by a sealing material such as glass frit. Further, a discharge cell partitioned by the partition wall is disposed between the two substrates of the front panel and the back panel, and a phosphor layer is formed in the cell space between the partition walls. In the plasma display device of such a configuration, ultraviolet rays are generated by gas discharge, and the phosphors of the respective colors of red (R), green (G), and blue (B) are excited by the ultraviolet light to emit light. This is a color display, and representative examples thereof include Japanese Patent No. 4226648 and the like.

In the case where the above display device is a field emission display device, a field emission display substrate is used as the display element substrate 62. The field emission display substrate is formed in a plurality of minute cathode electrodes (microchips) as electron emission sources in each pixel region, and the microchips corresponding to the corresponding pixel regions are excited according to the specific electrical signals, thereby being disposed on the anode electrode side. For example, the display substrate described in Japanese Laid-Open Patent Publication No. Hei 10-125262 can be used.

In the case where the above display device is a display device having a surface conduction type electron emitting element, a display substrate having a surface conduction type electron emitting element is used as the display element substrate 62. A display substrate having a surface conduction electron-emitting element emits electrons by a tunneling effect by applying a voltage between slits of a nanometer scale produced by an ultrafine particle film, thereby causing the phosphor to emit light.

In the case where the display device is an electronic paper, a display element of the display element substrate 62 is a liquid crystal method such as a cholesteric liquid crystal, an organic EL, a reflective film reflective display, an electrophoresis, a torsion ball, an electron coloring method, or a mechanical Reflective display, etc. can be.

Example

The present invention will be more specifically described below by way of examples, but the invention is not limited thereto. The following examples are set. In the examples, "%" and "parts" are % by mass and parts by mass unless otherwise specified.

Preparation Example 1 [Production Example of Photoalignment Polymer Represented by Formula (Z)]

A monomer represented by the formula (Z-a) (hereinafter abbreviated as a monomer (Z-a)) is produced according to the method described in Macromol. Chem. Phys. 197, 1919-1935 (1996). 1.5 parts of the obtained monomer (Z-a) and 0.1 part of methyl methacrylate were dissolved in 16 parts of tetrahydrofuran, and reacted at 60 ° C for 24 hours. After the reaction mixture is allowed to stand to room temperature, it is added dropwise to a mixed solution of toluene and methanol, whereby a photo-alignment polymer represented by the formula (Z) (hereinafter abbreviated as a photo-alignment polymer (Z)) is obtained. ). The photo-alignment polymer (Z) has a number average molecular weight of 33,000. In the photo-alignment polymer (Z), the content of the structural unit derived from the monomer (Z-a) is 75 mol%.

The polystyrene-equivalent number average molecular weight (Mn) of the obtained photo-alignment polymer (Z) was measured by a GPC method (Gel Permeation Chromatograph) under the following conditions.

Device: HLC-8220GPC (manufactured by Tosoh Co., Ltd.)

Column: TOSOH TSKgel MultiporeH _XL -M

Column temperature: 40 ° C

Solvent: THF (tetrahydrofuran, tetrahydrofuran)

Flow rate: 1.0 mL/min

Detector: RI (Refractive Index detector)

Standard materials for calibration: TSK STANDARD POLYSTYRENE F-40, F-4, F-288, A-5000, A-500

[Confirmation of physical properties of photo-aligned polymer layer]

A 5 mass% cyclopentanone solution of the photo-alignment polymer (Z) was applied onto a glass substrate, and dried at 120 ° C for 3 minutes to form a photo-alignment polymer layer. Then, SPOTCURE (SP-7, manufactured by Ushio Electric Co., Ltd.) equipped with a polarizing UV (ultraviolet) irradiation jig was irradiated with a illuminance of 15 mW/cm ² at a wavelength of 365 nm for 300 seconds (cumulative). The amount of light is 4500 mJ/cm ² ) linearly polarized. A(b)/A(a) and Δn(550) were determined for the photo-alignment polymer layer in the following manner, and the results are shown in Table 1.

[Absorbance change]

The absorbance (A(a)) at a wavelength of 314 nm and the photo-alignment polymerization after linear polarization were measured using an ultraviolet-visible spectrophotometer (UV-3150, manufactured by Shimadzu Corporation) at a wavelength of 314 nm before irradiation of linearly polarized light. The absorbance of the layer at a wavelength of 314 nm (A(b)).

[birefringence]

The optically-aligned polymer layer irradiated with linearly polarized light was measured at an wavelength of 550 nm by an ellipsometer (M-220, manufactured by JASCO Corporation). Phase difference. Further, the film thickness of the photo-alignment polymer layer was measured using a laser microscope (OLS-3000, manufactured by Olympus Co., Ltd.). The birefringence was obtained from the obtained phase difference and film thickness in accordance with the above formula (X).

Preparation Example 2 [Preparation of Liquid Crystal Composition]

The liquid crystal composition 1 was prepared by mixing the components described in Table 2.

Polymerizable liquid crystal compound: LC242 (manufactured by BASF JAPAN Co., Ltd., compound represented by formula (LC242))

Polymerization initiator: Irgacure 369 (manufactured by BASF JAPAN)

Leveling agent: BYK361N (manufactured by BYK-Chemie Japan)

Solvent: PGMEA (propylene glycol 1-monomethyl ether 2-acetate, manufactured by Tokyo Chemical Industry Co., Ltd.)

Example 1

A 5 mass% cyclopentanone solution of the photo-alignment polymer (Z) was applied onto a glass substrate, and dried at 120 ° C for 3 minutes to form a photo-alignment polymer layer having a film thickness of 307 nm.

Then, a photomask 1 (stainless steel) in which a stripe-shaped void portion (polarizing light transmitting portion) 2 is formed in the real portion (light shielding portion) 3 as shown in FIG. 1 is placed on the obtained photo-alignment polymer layer. The width of the void portion and the solid portion are each 280 μm), and the SPOTCURE (SP-7, manufactured by Ushio Electric Co., Ltd.) with a polarized UV irradiation fixture is used to reflect light under the conditions described in Table 3. The alignment polymer layer illuminates the first polarized light UV (linearly polarized UV) in a plane perpendicular direction.

Then, the photomask is removed, and the second polarized light UV is irradiated onto the entire surface of the photo-alignment polymer layer, thereby forming the first pattern region 12 and the second pattern including the mutually different retardation axes as shown in FIG. Patterned alignment film of region 13. The second polarized UV is irradiated with linearly polarized light having a vibration direction in a direction rotated by 90° with respect to the vibration direction of the first polarized light UV under the irradiation conditions described in Table 3.

The liquid crystal composition 1 was applied onto the surface on which the polarizing UV was applied using a spin coater to form a coating film. The coating film was kept at 100 ° C to obtain a film in which the liquid crystal components in the liquid crystal composition were aligned.

Thereafter, cooling to room temperature, using Unicure (VB-15201BY- A, Ushio Electric Co., Ltd.) at a wavelength of 365 nm at 40 mW / cm ² irradiance of ultraviolet rays irradiated one minute, whereby the polymerizable liquid crystal The compound was polymerized to produce an optically anisotropic layer (phase difference layer).

Examples 2 and 3

An optically anisotropic layer (phase difference layer) was formed on a glass substrate in the same manner as in Example 1 except that the irradiation conditions of the first and second polarized UVs were changed to the conditions described in Table 3.

Reference example 1

The irradiation condition of the first polarized light UV was changed to 2 minutes for the illuminance of 15 mW/cm ² (the integrated light amount was 1800 mJ/cm ² ), and the irradiation condition of the second polarized light UV was changed to the illuminance of 15 mW/cm. ² An optically anisotropic layer (phase difference layer) was formed on a glass substrate in the same manner as in Example 1 except that 5 minutes (accumulated light amount: 4500 mJ/cm ² ) was carried out.

Necessary conditions A: A(a)1.415, A(b)1.100, A(b)/A(a)=0.78 Required condition B: phase difference 1.35 nm, thickness 304 nm, Δn 0.004

[Measurement of optical properties]

The phase difference (nm) and the alignment angle of the optically anisotropic layer are measured without peeling off the optical anisotropic layer formed on the glass substrate to measure the machine (KOBRA- WPR, manufactured by Oji Scientific Instruments, Inc.). Since the glass substrate used for the substrate has almost no birefringence, the phase difference value of the optically anisotropic layer formed on the glass substrate can be obtained without measurement. The measurement results of the alignment angle of the liquid crystal component in the optical anisotropic layer and the phase difference at a wavelength of 549 nm are shown in Table 4. In the case of the optically anisotropic layer, when the alignment angle of the portion corresponding to the first pattern region 12 of the patterned alignment film and the portion corresponding to the second pattern region 13 is different, it indicates that the phases are different from each other. The area in the direction of the axis.

[observation of surface state]

The surface of the obtained optical anisotropic layer was observed at a magnification of 400 times by a polarizing microscope (BX51, manufactured by Olympus Co., Ltd.). The person who did not confirm the alignment defect on the surface was evaluated as "A" when the surface condition was good, and the "B" was evaluated as the surface state defect when the alignment defect was confirmed. The results are shown in Table 4.

Example 4 [Confirmation of physical properties of photoalignment polymer layer]

A 5 mass% cyclopentanone solution of the photo-alignment polymer (Z) was applied onto a glass substrate, and dried at 120 ° C for 3 minutes to form a photo-alignment polymer layer having a film thickness of 334 nm. Then, SPOTCURE (SP-7, manufactured by Ushio Electric Co., Ltd.) equipped with a polarized UV irradiation fixture was irradiated with a illuminance of 15 mW/cm ² at a wavelength of 365 nm for 300 seconds (accumulated light amount of 4500 mJ/cm ^{2 ).} ) Linear polarized light. A(b)/A(a) and Δn(550) were determined for the photo-alignment polymer layer in the same manner as above, and the results are shown in Table 5.

[Production of patterned phase difference layer]

A 5 mass% cyclopentanone solution of the photo-alignment polymer (Z) was applied onto a glass substrate, and dried at 120 ° C for 3 minutes to form a photo-alignment polymer layer having a film thickness of 334 nm. Then, a photomask 1 (stainless steel) in which a stripe-shaped void portion (polarizing light transmitting portion) 2 is formed in the real portion (light shielding portion) 3 as shown in FIG. 1 is placed on the obtained photo-alignment polymer layer. The width of the void portion and the solid portion are each 280 μm), and the SPOTCURE (SP-7, manufactured by Ushio Electric Co., Ltd.) equipped with a polarized UV irradiation fixture is self-relative to light under the conditions described in Table 6. The alignment polymer layer illuminates the linearly polarized light in a plane perpendicular direction.

Then, the photomask is removed, and the second alignment is irradiated to the entire surface of the photo-alignment polymer layer. The light UV forms a patterned alignment film including the first pattern region 12 and the second pattern region 13 having mutually different retardation axis directions as shown in FIG. The second polarized UV is irradiated with linearly polarized light having a vibration direction in a direction rotated by 90° with respect to the vibration direction of the first polarized light UV under the irradiation conditions described in Table 6.

The liquid crystal composition 1 was applied onto the surface on which the polarizing UV was applied using a spin coater to form a coating film. The coating film was kept at 100 ° C to obtain a film in which the liquid crystal components in the liquid crystal composition were aligned.

Thereafter, cooling to room temperature, using Unicure (VB-15201BY-A, Ushio Electric Co., Ltd.) at a wavelength of 365 nm at 40 mW / cm ² irradiance of ultraviolet rays irradiated one minute, whereby the polymerizable liquid crystal The compound was polymerized to produce an optically anisotropic layer (phase difference layer).

[View of pattern boundary line]

The width of the pattern boundary of the formed retardation layer was measured by a polarizing microscope (BX51, manufactured by Olympus Co., Ltd.), and it was confirmed that the thickness of the boundary line was 1.8 μm.

Comparative Example 1 [Production Example of Patterned Phase Difference Layer Using Secondary Mask]

A 5 mass% cyclopentanone solution of the photo-alignment polymer (Z) was applied onto a glass substrate and dried at 120 ° C for 3 minutes to form a light distribution having a film thickness of 334 nm. A directional polymer layer. Then, a photomask 1 (stainless steel) in which a stripe-shaped void portion (polarizing light transmitting portion) 2 is formed in the real portion (light shielding portion) 3 as shown in FIG. 1 is placed on the obtained photo-alignment polymer layer. The width of the void portion and the solid portion are each 280 μm), and the SPOTCURE (SP-7, manufactured by Ushio Electric Co., Ltd.) equipped with a polarized UV irradiation fixture is self-relative to light under the conditions described in Table 6. The alignment polymer layer illuminates the linearly polarized light in a plane perpendicular direction. When the reticle is placed, the marker is placed in advance in the end of the reticle.

Next, the reticle is replaced with a reticle (light-shielding portion) 3 as shown in FIG. 1 as a cavity portion (polarizing transmissive portion), and the cavity portion 2 is a reticle of a real portion, and the end portion is aligned with the marker to place the reticle. The photomask is irradiated with the second polarized light UV to the photo-alignment polymer layer, thereby forming a pattern including the first pattern region 12 and the second pattern region 13 having mutually different retardation axis directions as shown in FIG. The alignment film. The second polarized UV is irradiated with linearly polarized light having a vibration direction in a direction rotated by 90° with respect to the first polarized UV vibration direction under the irradiation conditions described in Table 6.

The liquid crystal composition 1 was applied onto the surface on which the polarizing UV was applied using a spin coater to form a coating film. The coating film was kept at 100 ° C to obtain a film in which the liquid crystal components in the liquid crystal composition were aligned.

Thereafter, cooling to room temperature, and used Unicure (VB-15201BY-A, Ushio Electric Co., Ltd.) at a wavelength of 365 nm at 40 mW / cm ² irradiance of ultraviolet rays irradiated one minute, whereby the polymerizable liquid crystal The compound was polymerized to produce an optically anisotropic layer (phase difference layer).

The width of the pattern boundary obtained in Comparative Example 1 was measured using a polarizing microscope, and as a result, it was confirmed that the thickness of the boundary line was 7.2 μm, which was wider than that of Example 4. The deviation of the degree becomes larger, that is, the positional deviation of the pattern becomes larger.

Industrial availability

According to the manufacturing method of the present invention, it is possible to obtain an optical anisotropic layer having a plurality of optically anisotropic regions having mutually different retardation axis directions without a positional deviation of the pattern.

1‧‧‧Photomask

2‧‧‧Voids

3‧‧‧ Real Department

51A‧‧‧Liquid crystal display device

51B‧‧‧Liquid crystal display device

52‧‧‧Backlight

53‧‧‧Polar plate

54‧‧‧Display element substrate

55‧‧‧ polarizing layer

56‧‧‧ patterned alignment film

57‧‧‧ phase difference layer

61A‧‧‧Liquid crystal display device

61B‧‧‧Liquid crystal display device

62‧‧‧Display element substrate

63‧‧‧ polarizing layer

64‧‧‧ patterned alignment film

65‧‧‧ phase difference layer

70a‧‧‧Transmission axis

71a‧‧‧late phase axis

71b‧‧‧late phase axis

71A‧‧‧ phase difference area (optical anisotropy area)

71B‧‧‧ phase difference area (optical anisotropy area)

Fig. 1 is a view showing an example of a configuration of a photomask used in the production method of the present invention.

Fig. 2 is a view showing an example of a patterned alignment film obtained by using the photomask of Fig. 1.

Fig. 3 is a schematic cross-sectional view showing a first aspect of the display device of the present invention.

Fig. 4 is a schematic cross-sectional view showing a second aspect of the display device of the present invention.

Fig. 5 is a schematic view showing the function of a phase difference layer (optical anisotropic layer).

Fig. 6 is a schematic cross-sectional view showing a third aspect of the display device of the present invention.

Fig. 7 is a schematic cross-sectional view showing a fourth aspect of the display device of the present invention.

1‧‧‧Photomask

2‧‧‧Voids

3‧‧‧ Real Department

Claims (8)

A method for producing an optically anisotropic layer formed of a liquid crystal composition containing a polymerizable liquid crystal compound and having a plurality of optically anisotropic regions having mutually different retardation axes, comprising: 1) a step of forming a photo-alignment polymer layer by applying a photo-alignment polymer onto a substrate, and (2) a first irradiation step of satisfying the following requirements A and B The photomask is irradiated with the first polarized light to the photo-alignment polymer layer, and (3) a second irradiation step is performed, after the irradiation of the first polarized light, irradiates the photo-alignment polymer layer with a vibration direction without passing through the photomask. a second polarized light having a first polarized light to form a patterned alignment film, and (4) a coating step of applying the liquid crystal composition onto the patterned alignment film to form a coating film, and (5) an alignment step The liquid crystal component contained in the coating film is maintained at a temperature in a liquid crystal state to form a film in which the liquid crystal component is aligned, and (6) a polymerization step in which the liquid crystal component is aligned in the film. Polymeric liquid crystallinity Polymerization; necessary condition A: The absorbance of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (i), A(b) / A(a) ≦ 0.95 (i) [in the formula (i), A (a) represents the absorbance at a wavelength of 314 nm before the first polarized light irradiation; A (b) represents the light absorption at a wavelength of 314 nm after the first polarized light irradiation. degree]. Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii), Δn (550) ≧ 0.005 (ii) [in the formula (ii), Δn (550) ) indicates a birefringence at a wavelength of 550 nm]. The method of claim 1, wherein the photo-alignment polymer is a polymer which can form a crosslinked structure by light irradiation. The manufacturing method of claim 1, wherein the angle between the vibration direction of the first polarized light and the vibration direction of the second polarized light is 70° to 90°. The method of claim 1, wherein the liquid crystal composition further comprises a polymerization initiator and a solvent. A manufacturing method comprising a layered body of an optically anisotropic layer and a substrate formed of a liquid crystal composition containing a polymerizable liquid crystal compound and having a plurality of optically anisotropic regions having mutually different retardation axes A manufacturing method comprising: (1) a step of forming a photo-alignment polymer layer, which is applied to a substrate by a photo-alignment polymer, and (2) a first irradiation step, which satisfies the following necessary condition A And the method of the requirement B is to irradiate the first polarized light to the photo-alignment polymer layer via a photomask, and (3) the second irradiation step, which is performed after the irradiation of the first polarized light, and is optically aligned without passing through the photomask. The polymer layer irradiates a second polarized light having a vibration direction different from the first polarized light to form a patterned alignment film, and (4) a coating step of coating the liquid on the patterned alignment film a coating composition is formed by a crystal composition, and (5) an alignment step of forming a film of a liquid crystal component by aligning the liquid crystal component contained in the coating film in a liquid crystal state (6) a polymerization step of polymerizing the liquid crystalline component contained in the aligned film in the alignment film; the necessary condition A: the absorbance of the photo-alignable polymer layer in the region irradiated with the first polarized light satisfies the formula (i) , A(b)/A(a)≦0.95 (i) [In the formula (i), A(a) represents the absorbance at a wavelength of 314 nm before the first polarized light irradiation; and A(b) represents the first polarized light after the irradiation. Absorbance at a wavelength of 314 nm]. Prerequisite B: The birefringence of the photo-alignment polymer layer in the region irradiated with the first polarized light satisfies the formula (ii), Δn (550) ≧ 0.005 (ii) [in the formula (ii), Δn (550) ) indicates a birefringence at a wavelength of 550 nm]. The method of claim 5, wherein the photo-alignment polymer is a polymer which can form a crosslinked structure by light irradiation. The manufacturing method of claim 5, wherein an angle formed by the vibration direction of the first polarized light and the vibration direction of the second polarized light is 70° to 90°. The method of claim 5, wherein the liquid crystal composition further comprises a polymerization initiator and a solvent.