TWI329787B - Photosensitive composition and fabrication of alignment films and compensation films thereof - Google Patents

Description

1329787 IX. Description of the Invention: TECHNICAL FIELD The present invention relates to a photosensitive composition, and more particularly to a method of forming an alignment film or an optical compensation film for a photosensitive composition. [Prior Art] Under the trend that the display area of the display device is getting larger and larger and the thickness is getting thinner, how to further align the liquid crystal molecules has always been an important issue in the liquid crystal display. In this research, in addition to the development of liquid crystal molecules, the alignment film and the compensation_design are also the focus of the project. f knowing the art towel, the alignment method usually forms the south molecular film on the substrate, and then aligns it by directional brapping. Although this method is simple and the alignment is stable, there are many problems as follows: (丨) Dust contamination, static residue, and scratches caused by brushing. (2) A single direction will result in a narrow angle of view 1 which does not conform to sparse (four) gallbladder. Therefore, how to coordinate in a secret way can be an opportunity to improve the above disadvantages. There are currently several methods of non-contact alignment, including photo-alignment, plasma beam alignment, and ion beam alignment. The light alignment is the use of polarized ultraviolet light to illuminate the alignment film in a specific direction to induce optical anisotropy, causing non-uniform photopolymerization, isomerization, or photocleavage reaction of the polymer on the surface of the film to make the surface of the film It has a special directionality and further induces the liquid crystal molecules to be aligned in the forward direction. Examples are as follows: (1) Photo-induced crosslinking: In the following formula, the branch of the polymer has an ethylene double bond and can carry out a [2+2] cyclization reaction. Such materials use a diamine-containing aromatic group (such as a biphenyl group having a diamine group) to react with phthalic anhydride (phthaHc anhydride) to form a polymer, which forms a polymer and then forms a film. The ultraviolet light causes the branched ethylene double bond to enter the 0854-A2i967TWF (N2): P54950072TW: hsuhLJche 5 1329787 cyclization reaction. This design is mainly based on the application of two different polymerization forms (the main chain is the amidation reaction, the branch is an ethylene double bond) to avoid the second crosslinking reaction being consumed in the first polymerization process. Functional group. The disadvantage is that the functional groups of the phthalic anhydride have a color that affects the transmittance.

0954-A21967TWF(N2); P54950072TW: hsuhuche 6 (2) Photo-induced isomerization: In the following formula, 'the azo group is converted from trans to forward (Cls) after illumination Since the polymerization of the main chain uses an amidation reaction of an amine group with an acid group, the azo group is not affected. After the main chain is polymerized to form a thin film, the branched azo group is isomerized by polarized ultraviolet rays to have an effect of an alignment film. However, this isomerization is not an irreversible reaction, especially after heating, its configuration will return from the forward direction to the reverse direction and lose the alignment effect. The lack of thermal stability is therefore an obstacle to the use of such materials in alignment films.

Ultraviolet light

(3) Photocracking type (ph〇t〇_indUCed decomposition) In the following formula, after the main chain is polymerized to form a film, the tetracyclic functional group is cleaved by polarized ultraviolet rays to have an alignment effect. This cleavage occurs in the main: 'The resulting film will have a change in its physical properties after cleavage. Such characteristics will cause problems in the subsequent fine adjustment (type of the substituent, number, degree of polymerization of the polymer, molecular weight, etc.). 0954-A21967TWF(N2) :P54950072TW; hsuhuche 7 1J29/87 The segment of the sub-group makes the ethylene double bond with R4 more reactive than R5, and R4 and r5 are independent of each other. . R2 and R3 include the following structures: an n_____ ^ —°-—R—〇—, .R # epc:12 n ^ horse or R3 is _, or _ •RN- -Κ- -C- surface stability-K - RN- -K-R- -0- wherein -N- -R- -RN- may form a functional group of the amine (the amine) which enhances the thermal stability of the polymer and the aromatic ring Such as phenyl, naphthyl, anthracenyl, or heterocyclic aromatic rings. The aromatic enthalpy is a stupid base. The heart and r2 at the substitution position of the benzene ring include an ortho position, and a 1-position-para position is preferably a para position. Further, the aromatic ring may contain more than one substituent, and the ethylene double bond having R4 has a different reactivity from the ethylene double bond having r5 by steric hindrance or electronic effect. These substituents include (a group of a group of V6, a group which forms a hydrogen bond with K or R3, and a hydrazine, such as a vine group, an acid group (hydrogen bond acceptor), a her group, and a silk (hydrogen bond donor). The hydrogen bond acceptor or the substituent of the donor is added to increase the steric hindrance of R2 or R3, thereby affecting the reactivity of the polymerization. However, in order to facilitate the synthesis, it is preferably a burnt group of ~. The above-mentioned additional substitution is beautiful, ~ and The relative substitution positions of the heart, as well as the types of R2 and R3, are such that there is a difference in the reactivity of the ethylene double bond with or with the heart. It is worth noting that there is a difference in reactivity of the double-bonded double bond of I or I. From the heart and heart 'not from I and R5. As a result, the more reactive ethylene double bond (having an R substituent) during the polymerization will form the skeleton of the filament, and the lower reactivity The bond (having 4 0954-A21967TWF(N2); P54950072TW; hsuhuche m 1329787 • Rb5 substituent) is retained as a branch of the polymer, and the UV or electrotreatment after the film is formed to form an alignment film or optical compensation film Briefly, the monomer of the present invention has two ethylene double bonds' The ethylene double bond of the compound 'is one of the ethylene double bonds as the ultraviolet alignment. The connection between Ar &, & ' does not simultaneously connect αγ with 〇, in order to avoid the Fnes rearrangement reaction. When & or R3 produces a Fries weight, the other can still carry out the polymerization reaction without affecting, and continue to polymerize to form a polymer. If there is a possibility of Fries rearrangement, a Fries rearrangement substituent will be generated. The reactivity of the ethylene double bond (which is a substituent linking Ar) is preferably less reactive than the substituent which does not cause Fries rearrangement. A preferred design includes lowering the activation energy of the polymerization reaction than the rearrangement reaction. Activation energy, avoiding the generation of rearrangement reaction by temperature and reagent; better design is to avoid the application of a substituent which will cause a rearrangement reaction. In the present invention, in order to further improve the polymerization rate of the photosensitive composition' Adding a photosensitive monomer such as methacrylate or the above M2 and a photoinitiator to the composition. If the m2 monomer is used, the product complexity of polymerization of the photosensitive monomer and the photosensitive polymer can be reduced. Only two B In order to increase the degree of Lu crosslinking, a thiol-acrylic acid having a polyethylenic double bond can be used, such as dipenthaerythiritol hexacrylate 'DPHA, which contains six double bonds. Five double-bonded dipentaerythritolpentacrylate (DPEPA), isopentaerythritol tetraacrylic acid with four double bonds (卩61^6巧1;11111;〇1{6杜&&(^1& [6,?£!1]), Trimethylolpropane Triacrylate (TMPTA) or tri-propyl propyl triacetate containing three double bonds Purpose (Pentaerythritol Triacrylate, PETA). These photosensitive monomers can improve the photohardening speed of the photosensitive composition of 0954-A2l967TWF(N2): P54950072TW: hsuhuche 1329787. In order to make the photosensitive monomer (8) and the photosensitive polymer (the light-initiating agent of the present invention can be ----------------------------------------------- : a combination of the above substances 'such as 2_ mercapto-phenylphenyl propyl yroxy-2-methyl-l-phenyl-pr〇pan.!_one) . = base sulfide, 2 · benzyl 2 Dimethylamino[4_(methylthio)phenyl p Ma Shi Xifeng Propylene-1-1, 22 —- 7 1 9 7 ρ , Ethyl-2-N-Benzylbenzene-, 2-indenyl In the preferred embodiment of the present invention, the photosensitive polymer accounts for 80 i 90 parts by weight of the '''''''''''''''''''' The photosensitive monomer accounts for 5_1G parts by weight, and the photoinitiator accounts for 2_ig parts by weight. The present invention is coated with the solution and coated on the substrate and heated to remove the solvent. Then, the non-polarized ultraviolet light irradiates the substrate at a non-perpendicular angle, and then irradiates the substrate vertically or obliquely with polarized ultraviolet rays to form an alignment film. The solvent is preferably a polar apn tic solvent. DMF. The method of applying the solution to the substrate is preferably Rotary coating method, the coating method can be completed in one time, or the flow is evenly made at a slow speed, and then the film thickness is uniform, and the film thickness is preferably 〇]. The method of heating the substrate by pen rice is preferably two. Segment heating, first softly bake at a lower temperature (90-120C) for a shorter period of time (<15 minutes), then remove at a higher temperature (14〇_17〇.〇hard roast for a longer period of time (>25 minutes)' The thickness of the film after the solvent is between 〇〇5_1() and the size of the substrate includes the glass substrate of the liquid crystal display and the flexible plastic substrate. The non-polar ultraviolet light has a lower exposure (〇_1〇〇mj/ Cm2) Irradiation, non-vertical angle (15-75 degrees, preferably 45 degrees) to illuminate the film. Polar ultraviolet light is 0854-A21967TWF (N2): P54950072TW: hsuhuche 1329787 equivalent exposure! (50-500mJ/cm2) The film on the substrate is irradiated perpendicularly or non-perpendicularly, and the formed alignment film has good quality, so that the liquid crystal molecules have a pretilt angle of 0-90 degrees, and the angle size is the end view of the polymer type forming the alignment film. The key to the formation of the above alignment film by ultraviolet light is the branched ethylene. Whether the bond participates in the polymerization in the polymerization process. If it is not involved in the polymerization, the ultraviolet process can react the ethylene double bond remaining on the branch to achieve the alignment effect. In addition, the photosensitive monomer can accelerate the photohardening speed of the photopolymer. ,reduce

The exposure intensity and time of the UV source can reduce process costs and speed up production. The alignment film provided by the invention has the following characteristics: uniform alignment uniformity, average anchoring energy (about 1 〇 -5 erg/cm 2 ), thermal stability (heating ^ is higher than the phase transition point (clearp〇int) When urc is maintained for 10 minutes or more, it has uniform alignment, does not deteriorate the alignment property by heating, and has good solvent resistance, and does not deteriorate the alignment property by the solvent in the photosensitive liquid crystal solution. In addition, the alignment film attached to the inner side of the substrate directly contacts the liquid crystal to make it aligned; and the optical compensation 贴 attached to the outside of the substrate prevents the ring from being reflected by the metal gate in the liquid crystal display. The invention has both uses. The method of forming the optical compensation film is as follows: the photosensitive composition is dissolved in a solvent to form a solution, and then applied to the substrate. Then, the substrate is heated to remove the solvent, and the substrate is irradiated with ultraviolet rays to form a film, and then The photoreactive liquid crystal is coated on the alignment film, and the liquid crystal is irradiated with a non-polarity violet line to form an optical compensation film.卜 [Preferred Example] Example 1-1 0954-A21967TWF (N2): P54950072TW; hsuhuche 1329787 4-mercaptopropylamino-mercaptomethyl propyl ester and fully isopropyl methyl Copolymer 1 of propylene ester 1 0.5 g (2 mmol) of 4-mercaptopropenylnonylamino-phenol decyl acrylate, 0.375 g (1.4 mmol) of perfluoropropyl methacrylate (2, 2,3,3-tetrafluoropropylmethacrylate) and 0.00875 g of AIBN 'dissolved in 10 mL of DMF and isolated from air at 8 Torr. After reacting for 20 minutes under the armpit, the reaction was slowly dropped into the mixture at room temperature. Ethyl ether (2 〇〇 • mL). After filtration, 0.374 g (yield 42.7%) of the copolymer was obtained; [R(KBr), gin cm-1: broad 3430, 3350 (NH), 1750 (-〇_ C-〇-), 1670 (amide), 1510, 1260, 962, 945, 879, 661 (aryl), other signals such as 2940, 1410, 1390, 1320, 1200, 1170, 1130, 1100, 1002, 833, 525 Copolymer of 4-mercaptopropenylamino-phenolic methacrylate with perfluoropropylmethyl propyl ester 2 Take 0.91 g (4 mmol) of 4-mercaptopropenyl amide - phenol mercaptopropyl acrylate, 1 g (5 mmol) of perfluoropropene The propyl isopropyl ester and 0.0191 g of Φ AIBN were dissolved in 24 mL of DMF and then isolated from the air. After reacting at 8 ° C for 40 minutes, the reaction was slowly dropped into diethyl ether under stirring at room temperature ( 200 mL). After filtration, 0.24 g (yield 12%) of copolymer 2. IR (KBr), cm · broad 3392 (NH) 5 1752 (-0-C-0-) » 1668 (amide) 5 508, 1253, 965, 904, 664 (aryl), other signals such as 2937, 1408, 1392, 1170, 1156, 1128, 1016, 805, 712. 4-methylpropenyl decyl-phenol methacryl Copolymer of perester with perfluoropropylmethyl propyl ester 3 0954-A2196 丌WF(N2): P54950072TW: hSuhuche 1-329787 0.399 g (1.6 mmol) of 4-mercaptopropenyl decyl-phenol Base propylene acrylate, 0.760 g (3.8 mmol) of perfluoropropyl methacrylate and 0.0116 g of AIBN, dissolved in 5 mL of DMF and isolated from air, reacted at 80 ° C for 50 minutes, The reaction was slowly added dropwise to diethyl ether (100 mL) stirred at room temperature. After filtration, 0.062 g (yield 70/?) of the copolymer 3 was obtained. 4-Methylpropyl decylamino-dimethyl propylene condensed with all-indenyl methacrylic copolymer 4 Take 0.6 g (2.4 mmol) of 4-mercaptopropyl amide Base-test thioglycol acrylate, 0.072 g (0.24 mmol) of perfluorofluorenyl propyl acrylate (2,2,3,3,4,4,5,5-〇(^1111〇1) :〇卩61^111^11&〇7 as 6) and 0.0067 AI AIBN' dissolved in 10mL of DMF and isolated from air, reacted at 80 °C for 165 minutes, then slowly drip the reaction into room temperature The ether was stirred (1 mL • mL). After filtration, 0.2658 g (yield 39%) of the copolymer 4. IR (KBr), • cm_1 : broad 3440 (NH), 1750 (-OCO-), 1670 (amide), 1510, 1260, 964, 661 (aryl), other signals such as 2940, 1410, 1390, 1320, 1200, 1170, 1130, 1100, 1002, 816, 714, • 525 ° 4-methyl propylene Copolymer of amidino-dimethylmethyl propyl ester and perfluoroj pentyl methacrylate 5 Take 0.4 g (1.6 mmol) of 4-mercaptopropenyl aryl methacrylate Ester, 0.342 g (1.1 mmol) of perfluoropentyl decyl acrylate and • 0.0074 g of AIBN' dissolved in 7 mL of DMF and isolated from air. After reacting for 35 minutes at 80 C, the reaction mixture was slowly dropped into diethyl ether (100 mL) at room temperature. After filtration, y. i985 g (yield 26 8%) of copolymerized 0954-A21967TWF (N2) was obtained. :P54950072TW;hsuhuche 1329787 5.H (KBr), cm-1 : broad 3420 (NH), 1750 (-0-C-0-), 1670 (amide), 1510, 1260, 966, 663 (aryl), Other signals such as 2940, 1410, 1390, 1320, 1200, 1170, 1130' 1050, 1002, 810, 525. 4-Methylpropenyl decyl-phenol methacrylate and perfluoropentyl methacrylate Ester Copolymer 6 Take 0.74 g (3 mmol) of 4-mercaptopropenylnonylamino-phenolic methacrylate, 0.9 g (3 mmol) of perfluoropentyl methacrylate and 0.0164 g of punch The AIBN was dissolved in 22 mL of DMF and isolated from air at 80. (After 3 minutes of reaction for 3 minutes, the reaction was slowly added dropwise to diethyl ether (200 mL) stirred at room temperature. After filtration, 0.32 g (yield 54%) of the copolymer 6 〇IR (KBr), cm-1 : broad 3392 (NH), 1752 (-0-C-0-), 1668 (amide), 1508, 1253, 965, 904, 664 (aryl), other signals such as 2937, 1408, 1392, 1170, 1156, 1128, 1016, 805, 712. Copolymer of 4-methylpropenylnonyl-phenolic methacrylate with perfluorofluorenyl methacrylate Ί 0.225 g (0.9 _〇1) of 4-methylpropenyl amide - phenolyl methacrylate, 0.646 g (2.2 mmol) of perfluorofluorenyl decyl acrylate and 〇0087 g of AIBN, dissolved in 5 mL of DMF, isolated from air and reacted at 80 ° C for 45 minutes After the reaction, the reaction mixture was slowly added dropwise to diethyl ether (1 mL) stirred at room temperature. After filtration, 0.181 g (yield 20.7%) of the copolymer 7 was obtained. Copolymer of 4-methylpropenylnonyl-phenolic methacrylate with octylmethacrylic acid vinel 8. 0.43 g (1.7 mmol) of 4-methylpropenyl allysyl-phenol fluorenyl 0954 -A21967TWF(N2);P54950072TW;hsuhuche 1-329787 propyl ester, 〇· 17 g (0.85 mmol) of octylmercaptopropyl acrylate

(octylmethacrylate) with 0.0060 g of AIBN, dissolved in 6 mL of DMF and isolated from air. After reacting at 80 ° C for 60 minutes, the reaction was slowly added dropwise to ether (1 mL) stirred at room temperature. . After filtration, 0.0862 g (yield 14.4%) of copolymer 4 was obtained. Example 1-2 Preparation of alignment film 80 parts by weight of copolymer 1-8, 10 parts by weight of diisotetradecyl hexapropanoate (DPHA), and 5 parts by weight of photoinitiator were dissolved in DMF, forming a photosensitive composition solution. Next, the above solution was spin-coated on a glass containing an ITO electrode at a rate of 3,500 rpm, and baked at 180 ° C for 1.5 hours to remove DMF. The substrate is then taken out of the oven and returned to room temperature. • The photosensitive composition on the substrate is irradiated with ultraviolet light generated by a high pressure mercury lamp as shown in Fig. 1. First, the film was irradiated with a polarized ultraviolet light at an angle of 45 degrees (the exposure amount was about 50 mJ/cm2). Thereafter, a polarizing plate was added, and the film was vertically irradiated with non-polarized ultraviolet rays (exposure amount of about 50 mJ/cm2) to form a aligning film. The above-mentioned polarization and non-polarized ultraviolet light have a single wavelength (254 nm). In addition to forming a alignment film by a two-stage exposure process of a single wavelength. The present invention can also perform a single exposure process using an ultraviolet band (270-400 nm), such as illuminating the film at a tilt angle of 45 degrees in a polarized ultraviolet band to form an optical The compensation film has an exposure amount of less than 50 mJ/cm 2 . Comparative Example Copolymer 1-8 was dissolved in DMF to form a photosensitive composition solution. Next, the above solution was spin-coated at a rate of 3,500 rpm to a glass containing 0954-A21967TWF(N2); P54950072TW; hsuhuche 1-329787 ITO electrode, and baked at 180 ° C for 1.5 hours to remove DMF. The substrate is then removed from the oven and returned to room temperature, and the polymer or copolymer film on the substrate is irradiated with ultraviolet light generated by a high pressure mercury lamp. First, the film was irradiated with a polarized ultraviolet light at an angle of 45 degrees (the exposure amount was about 360 mJ/cm2). Thereafter, a polarizing plate was added, and the film was vertically irradiated with non-polarized ultraviolet rays (exposure amount of about 360 mJ/cm2). Since the comparative non-photosensitive monomer and the photoinitiator help harden, the exposure amount is much larger than that of the embodiment of the present invention.

0954-A21967TWF(N2): P54950072TW; hsuhuche 1329787 [Simple description of the drawing] Fig. 1 is a schematic view showing the formation of an alignment film by two-stage ultraviolet rays. [Main component symbol description] #»»,

0954-A21967TWF(N2); P54950072TW: hsuhuche 19

Claims (1)

1329787 Revision No. 95149176: 99.7 14 '10. Scope of application: Amendment 1. A photosensitive composition 'a composition age a. 80 to 90 parts by weight of photosensitive polya 舲 - 卜 M2" i - 〇 ',, the structural formula is as follows: \ /η R1 ] where Μ! is a fluoride functional group containing a hydrophobic functional group, m: n is between 0:100-99:1 R] monomer, R] is Ci_Ci2 M2 The structure is as follows: R4 〇Oh _I II II Is H2c c C-R2-Ar-R3— ---i=cn , such that the ethylene double bond having R4 in which h and R3 are different from each other is a double bond containing a hetero atom. A female double bond having R5 & R4, R5 are each independently selected from the group consisting of hydrazine or CH3: Ar-based aromatic ring; b. 5 to H) by weight of photosensitive monomer, including methyl acrylate vinegar or M2 And # c. 2 to 10 parts by weight of a photoinitiator. 2. The photosensitive composition according to claim 1, wherein the methacrylic acid monomer comprises Dipenthaerythiritol hexacrylate (DPHA), dipentaerythritol penta vinegar (Dipentaerythritol penta) Acrylate, DPEPA), pentaerythritol tetraacrylate (PETIA), trimethylolpropane triacrylate (TMPTA), or pentaerythritol triacrylate (Pentaerythritol Triacrylate, PETA). Χ->. 20 Revision No. 95149176 Date: 99.7.14 Amendment 3, as in the photosensitive composition described in claim 1, wherein Rw is placed in a white ΠΓ 5丨丨 from the lecture. _H_ . ', R2 and R3 are selected from the following structures: '〇" ---RO-- •R- Η _Ν_ •R-〇- -M- -R- -S- 'R- where R is C〗-C12 base. 4. The photosensitive composition according to claim 1, wherein Ar of M2 comprises a phenyl group, a naphthyl group, an anthracenyl group or a heterocyclic aromatic ring. ▲ - 5. The photosensitive composition according to claim 4, wherein 5 is a phenyl group, and I and R3 are aligned at a relative position of the benzene ring substitution. 6. As claimed in the patent range, the substituent of the aromatic ring is in addition to the group. The photosensitive composition of claim 4, wherein R2 and R3' further comprise one or more substitutions. 7. The photosensitive composition of claim 6, wherein the one or more substituents comprise an alkyl group of CrC6. base. A method for forming an alignment film, comprising: dissolving a photosensitive composition according to claim 1 in a solvent to form a solution; coating the solution on a substrate; heating the substrate to remove the a solvent; irradiating the substrate with a polarized ultraviolet light; and irradiating the substrate with a non-polarized ultraviolet light at a non-perpendicular angle to form an alignment film. 9. The method for forming an alignment film according to claim 8 of the patent application, 1329787, No. 5149Γ76, date of revision: 99.7.14 Amendment 8 The reading of the photosensitive polymer is in the range of G '5 wi%. The method for forming an alignment film according to the eighth aspect of the invention, wherein the method of coating the solution onto the substrate comprises a spin coating method. 11. The method of forming an alignment film according to item 8 of the patent of the fifth aspect of the present invention, wherein the substrate comprises a thin film electro-crystal (tetra)-array basic color-dye substrate of a liquid crystal display. For example, the method for forming an alignment film according to item 8 of the φ 4 patent side, "the energy of the polarized ultraviolet light is smaller than the non-polarized ultraviolet light. The formation method of the pot m material (4) 8 Gu Xu (10), purple secret irradiation The straight angle of the surface of the silk plate is 14. The method for forming an optical compensation film, comprising: the agent: the photosensitive composition described in the first item is dissolved and dissolved, and the solution is coated on a substrate; The substrate is used to remove the solvent; the substrate is irradiated with an ultraviolet ray to form an optical compensation medium. The optical enthalpy method of claim 14, wherein the ultraviolet ray comprises an outer line of a non-polarized ultraviolet ray film. Polarized violet 22