JP2008276165A - Photosensitive material for forming optically functional layer, composition for forming optically functional layer, optically functional film, and production method of optically functional film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optically functional film which has a transparent substrate and an optically functional layer directly formed on the transparent substrate without any alignment layer interposed in between, and containing a liquid crystalline material, is excellent in materializing an optical function, and has only slight haze, and a photosensitive compound for forming the optically functional layer used therefor. <P>SOLUTION: The invention includes: a photosensitive compound for forming the optically functional layer which is characterized in that it has a photoreactive group exhibiting photoreactivity and a lyophobic group exhibiting a lyophobic property; the transparent substrate; and the optically functional film formed on the transparent substrate and having the optically functional layer containing a reaction product of the photosensitive compound for forming the optically functional layer related to the invention, and a cross-linked product of a cross-linking liquid crystal material with a cross-linking functional group, and is characterized in that the reaction product of the photosensitive compound for forming the optically functional layer is unevenly distributed on the surface of the optically functional layer on the side opposite to the transparent substrate. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical functional film used for a viewing angle compensation film for a liquid crystal display device, and a photosensitive compound for forming an optical functional layer used therefor.

  The liquid crystal display device has features such as power saving, light weight, thinness, and the like, and has rapidly spread in recent years in place of the conventional CRT display. As a general liquid crystal display device, as shown in FIG. 4, a liquid crystal display device having an incident side polarizing plate 102 </ b> A, an outgoing side polarizing plate 102 </ b> B, and a liquid crystal cell 101 can be exemplified. The polarizing plates 102A and 102B are configured to selectively transmit only linearly polarized light (schematically illustrated by arrows in the figure) having a vibration surface in a predetermined vibration direction. They are arranged to face each other in a crossed Nicol state so as to have a right angle relationship with each other. The liquid crystal cell 101 includes a large number of cells corresponding to the pixels, and is disposed between the polarizing plates 102A and 102B.

  The liquid crystal display device has a problem of viewing angle characteristics as a peculiar defect. The problem of viewing angle characteristics is a problem in which contrast, color, and the like change between when the liquid crystal display device is viewed from the front and when viewed from an oblique direction. Such a problem is caused by the fact that the liquid crystal cell used in the liquid crystal display device has birefringence and has two polarizing plates arranged in crossed Nicols.

  Various techniques have been developed so far to improve such viewing angle characteristics. One of the typical methods is a method using a retardation film having a predetermined birefringence. This method using a retardation film is a method for improving viewing angle characteristics by disposing a retardation film exhibiting a predetermined birefringence between a liquid crystal cell and a polarizing plate in a liquid crystal display device. Such a method can improve the viewing angle dependency problem of a liquid crystal display device using a liquid crystal cell having various optical characteristics by using a retardation film having different birefringence depending on the type of the liquid crystal cell. In this respect, it is useful in liquid crystal display devices that employ various display methods.

  As the retardation film, those having a substrate, an alignment film formed on the substrate, and a retardation layer formed on the alignment film and containing a liquid crystal material have been widely used. It was. Such a retardation film can exhibit desired birefringence when the liquid crystal material is regularly arranged in the retardation layer in accordance with the alignment regulating force of the alignment film.

  By the way, in recent years, a retardation film that does not require the alignment film as the retardation film, that is, a retardation film having a structure in which a retardation layer is directly formed on the substrate has been developed (Patent Document 1). And Patent Document 2). Such a retardation film that does not require an alignment film is capable of three-dimensional alignment of a liquid crystal material, which has been difficult to achieve with a retardation film using a conventional alignment film, and has a plurality of positions. It has an advantage that a retardation layer can be laminated, and furthermore, a manufacturing process of a retardation film can be simplified.

  However, in the retardation films disclosed in Patent Document 1 and Patent Document 2, a liquid crystal material and an alignment compound that aligns the liquid crystal material are mixed as a retardation layer that exhibits retardation. Therefore, there is a drawback that the alignment of the liquid crystal material is hindered by the presence of the alignment compound. If the alignment of the liquid crystal material is hindered, the haze of the retardation layer is increased or the expression of retardation is reduced, so in a retardation film that does not use such an alignment film. In addition, there is a problem that it is difficult to obtain a retardation film excellent in transparency and retardation.

Special table 2002-517605 gazette JP 2002-82224 A

  The present invention has been made in view of the above problems, and is an optical functional film having a transparent substrate and an optical functional layer formed directly on the transparent substrate without an alignment film and containing a liquid crystalline material. The main object of the present invention is to provide an optical functional film having excellent optical function and low haze, and a photosensitive compound for forming an optical functional layer used therefor.

  In order to solve the above problems, the present invention provides a photosensitive compound for forming an optical functional layer, which has a photoreactive group exhibiting photoreactivity and a lyophobic group exhibiting lyophobicity. To do.

  Since the photosensitive compound for forming an optical functional layer of the present invention has the lyophobic group, for example, the photosensitive compound for forming an optical functional layer of the present invention is mixed with a liquid crystal material to prepare a coating solution, When forming an optical functional layer using this, the optical functional layer in which the photosensitive compound for forming an optical functional layer or a reaction product thereof is unevenly distributed on the surface can be formed. For this reason, according to the photosensitive compound for forming an optical functional layer of the present invention, the alignment of the liquid crystal material can be improved in the optical functional layer, so that the optical function has excellent optical function and has a small haze. A layer can be formed.

  In the present invention, the lyophobic group preferably contains silicon or fluorine. In the present invention, the lyophobic group is preferably a dimethylsiloxane chain or a fluoroalkyl chain. By having such a lyophobic group, the photosensitive compound for forming an optical functional layer of the present invention can be made more lyophobic. Therefore, the photosensitive compound for forming an optical functional layer of the present invention, a liquid crystal material, When the coating solution is prepared by mixing and forming an optical functional layer using this, uneven distribution on the surface of the photosensitive compound for forming an optical functional layer or a reaction product thereof can be made more remarkable. Due to the uneven distribution of the photosensitive compound for forming an optical functional layer or a reaction product thereof on the surface, an optical functional film having excellent optical function and low haze is obtained using the photosensitive compound for forming an optical functional layer of the present invention. It is because it becomes possible to manufacture.

  In the present invention, the photoreactive group may have a mesogenic structure. Since the photoreactive group has a mesogenic structure, it becomes possible to produce an optical functional film having further excellent optical function using the photosensitive compound for forming an optical functional layer of the present invention. is there.

  Furthermore, the photosensitive compound for forming an optical functional layer of the present invention is obtained by copolymerizing the photoreactive monomer having the photoreactive group and the lyophobic monomer having the lyophobic group. Also good. By having such a structure, for example, by appropriately changing the polymerization ratio between the photoreactive monomer and the lyophobic monomer, the lyophobic property exhibited by the photosensitive compound for forming an optical functional layer of the present invention is shown. This is because it can be easily adjusted as desired according to the specific use of the photosensitive compound for forming an optical functional layer of the present invention.

  In order to solve the above-mentioned problems, the present invention includes an optical functional layer forming comprising the photosensitive compound for forming an optical functional layer according to the present invention and a crosslinkable liquid crystal material having a crosslinkable functional group. A composition is provided.

  Since the composition for forming an optical functional layer of the present invention contains the photosensitive compound for forming an optical functional layer according to the present invention, the optical functional layer is formed by coating the composition for forming an optical functional layer of the present invention. In this case, an optical functional layer in which the photosensitive compound for forming an optical functional layer or a reaction product thereof is unevenly distributed on the surface can be formed. For this reason, in the optical functional layer formed using the composition for forming an optical functional layer of the present invention, the alignment of the crosslinkable liquid crystal material is inhibited by the presence of the photosensitive compound for forming an optical functional layer. Can be reduced. For this reason, according to the present invention, it is possible to form an optical functional layer having excellent optical function and low haze.

  The composition for forming an optical functional layer of the present invention preferably contains a solvent. When the optical functional layer is formed by coating the composition for forming an optical functional layer of the present invention by including a solvent, the optical functional layer in which the photosensitive compound for forming an optical functional layer is unevenly distributed on the surface is provided. This is because it can be formed, so that it is possible to form an optical functional film that is further excellent in optical function expression and has a small haze.

  In the composition for forming an optical functional layer of the present invention, the content of the photosensitive compound for forming an optical functional layer is preferably 1% by mass or less based on the total solid content. This is because an optical functional layer having a smaller haze can be formed using the composition for forming an optical functional layer of the present invention.

  Moreover, in order to solve the said subject, this invention has a crosslinkable functional group and the reaction material of the photosensitive compound for optical function layer formation which is formed on the transparent substrate and the said transparent substrate according to the said this invention. An optical functional film having an optical functional layer containing a cross-linked product of a cross-linkable liquid crystal material, wherein the reaction product of the photosensitive compound for forming an optical functional layer is opposite to the transparent substrate of the optical functional layer. Provided is an optical functional film characterized by being unevenly distributed on the surface.

  According to the present invention, the reaction product of the photosensitive compound for forming an optical functional layer in the optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate. The presence of the reaction product of the photosensitive compound for forming an optical functional layer in the layer can prevent the alignment of the cross-linked product of the cross-linkable liquid crystal material from being inhibited. For this reason, according to this invention, the optical function film which is excellent in the expressibility of an optical function and has a small haze can be obtained.

  In the optical functional film of the present invention, the content of the reaction product of the photosensitive compound for forming an optical functional layer in the optical functional layer is preferably 1% by mass or less. This is because the optical functional film of the present invention can have a smaller haze.

  Furthermore, in order to solve the said subject, this invention forms the layer for optical function layer formation on the said transparent substrate by applying the composition for optical function layer formation concerning the said invention using a transparent substrate. An optical functional layer forming layer forming step, and the optical functional layer forming layer is irradiated with polarized ultraviolet light and reacted with the photoreactive group to align the optical functional layer forming layer with the crosslinkable liquid crystal material. An optical function characterized by comprising: an alignment imparting step for imparting a property; a liquid crystal alignment step for aligning the crosslinkable liquid crystal material; and a liquid crystal crosslinking step for crosslinking the crosslinkable liquid crystal material. A method for producing a film is provided.

  According to the present invention, since the optical functional layer forming composition according to the present invention is used as the optical functional layer forming composition, an optical functional layer having excellent optical function and low haze can be obtained. An optical functional film provided can be manufactured. For this reason, according to the method for producing an optical functional film of the present invention, an optical functional film having excellent optical function and low haze can be obtained.

  The present invention is an optical functional film having a transparent substrate and an optical functional layer that is directly formed on the transparent substrate without an alignment film and contains a liquid crystalline material, and has excellent optical function, There exists an effect that the optical function film with a small haze can be obtained.

The present invention relates to a photosensitive compound for forming an optical functional layer, a composition for forming an optical functional layer using the same, a method for producing an optical functional film using the same, and an optical functional film.
Hereinafter, the photosensitive compound for forming an optical functional layer, the composition for forming an optical functional layer, the method for producing an optical functional film, and the optical functional film of the present invention will be described in order.

A. First, the photosensitive compound for forming an optical functional layer of the present invention will be described. The photosensitive compound for forming an optical functional layer of the present invention is characterized by having a photoreactive group exhibiting photoreactivity and a lyophobic group exhibiting lyophobic properties.

  Since the photosensitive compound for forming an optical functional layer of the present invention has the lyophobic group, for example, the photosensitive compound for forming an optical functional layer of the present invention is mixed with a liquid crystal material to prepare a coating solution, When the optical functional layer is formed using this, the optical functional layer in which the photosensitive compound for forming an optical functional layer or a reaction product thereof is unevenly distributed on the surface can be formed. Therefore, according to the photosensitive compound for forming an optical functional layer of the present invention, the alignment of the liquid crystal material can be improved in the optical functional layer, so that the optical function is excellent in optical function and has a small haze. A layer can be formed.

Here, the reason why an optical functional layer having excellent optical function and low haze can be formed by using the photosensitive compound for forming an optical functional layer of the present invention will be described more specifically.
The photosensitive compound for forming an optical functional layer of the present invention is used by being mixed with a rod-shaped compound having refractive index anisotropy such as a liquid crystal material, and the liquid crystal material is regularly arranged to provide a predetermined optical function. It is used to form an optical function layer that develops.
FIG. 1 is a schematic view showing an example of a method for forming an optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention. As exemplified in FIG. 1, as a method for forming an optical functional layer using the compound for forming an optical functional layer of the present invention, a transparent substrate 1 is usually used (FIG. 1 (a)), and the transparent substrate 1 is formed. A composition for forming an optical functional layer containing the photosensitive compound for forming an optical functional layer of the present invention and a crosslinkable liquid crystal material is applied, and an optical functional layer forming layer 2 ′ is formed on the transparent substrate 1. The optical functional layer-forming photosensitive compound of the present invention is formed by irradiating the optical functional layer-forming layer forming step (FIG. 1B) to be formed and the optical functional layer-forming layer 2 ′ with polarized ultraviolet rays. An orientation imparting step (FIG. 1 (c)) for imparting orientation to the crosslinkable liquid crystal material to the optical functional layer forming layer 2 ′ by reacting the photoreactive group, and for forming the optical functional layer By heating the layer 2 ', the crosslinkable liquid crystal material is attached by the above-described orientation imparting step. A liquid crystal alignment step (FIG. 1 (d)) for aligning according to the given orientation, and crosslinking the crosslinkable liquid crystal material aligned by the liquid crystal alignment step by irradiating the optical function layer forming layer 2 ′ with ultraviolet rays. The method of forming the optical functional layer 2 having the regularly arranged crosslinkable liquid crystal material on the transparent substrate 1 by the liquid crystal crosslinking step (FIG. 1E) is used.

As described above, the optical functional layer formed using the photosensitive compound for forming an optical functional layer of the present invention exhibits a predetermined optical function by regularly arranging the crosslinkable liquid crystal material. . And the photosensitive compound for optical function layer formation of this invention has the function to arrange the said crosslinkable liquid-crystal material, when the said photoreactive group reacts with polarized ultraviolet rays.
Here, the crosslinkable liquid crystal material has an alignment property that regularly arranges in a temperature range higher than the crystal-liquid crystal phase transition temperature and lower than the liquid crystal phase-isotropic phase transition temperature. It tends to be easily damaged by the presence of the compound. As the other compound that impairs the alignment, the photosensitive compound for forming an optical functional layer of the present invention is no exception. Therefore, in the optical functional layer formed using the photosensitive compound for forming an optical functional layer of the present invention, when the photosensitive compound for forming an optical functional layer of the present invention and the crosslinkable liquid crystal material are mixed, The alignment property of the crosslinkable liquid crystal material is impaired by the presence of the photosensitive compound for forming an optical functional layer.
In this regard, the photosensitive compound for forming an optical functional layer according to the present invention is unevenly distributed on the surface in the optical functional layer forming layer formed in the optical functional layer forming layer forming step by having the lyophobic group. It has the property to do. That is, when the photosensitive compound for forming an optical functional layer of the present invention has the lyophobic group, the molecule as a whole exhibits lyophobic properties with respect to the liquid used in the composition for forming an optical functional layer. . Therefore, the photosensitive compound for forming an optical functional layer of the present invention forms an optical functional layer forming layer by drying the coating film of the optical functional layer forming composition in the optical functional layer forming layer forming step. In this case, it can be unevenly distributed on the surface of the optical functional layer forming layer by lyophobic interaction.
Therefore, in the optical functional layer formed using the optical functional layer-forming photosensitive compound of the present invention, most of the optical functional layer-forming photosensitive compound of the present invention is composed of the crosslinkable liquid crystal material. Since it exists without mixing, it can prevent that the arrangement | sequence of the said crosslinkable liquid crystal material is inhibited by presence of the photosensitive compound for optical function layer formation of this invention. For this reason, the optical functional layer formed using the photosensitive compound for forming an optical functional layer of the present invention is one in which the crosslinkable liquid crystal material is arranged with high regularity. The haze becomes small.

The photosensitive compound for forming an optical functional layer of the present invention has the lyophobic group and the photoreactive group.
Hereinafter, such a photosensitive compound for forming an optical functional layer of the present invention will be described in detail.

1. First, the lyophobic group used in the present invention will be described. The lyophobic group used in the present invention is lyophobic. By having such a lyophobic group, the photosensitive compound for forming an optical functional layer of the present invention can form an optical functional layer having excellent optical function and low haze.

  As the lyophobic group used in the present invention, in the optical functional layer formed using the photosensitive compound for forming an optical functional layer of the present invention, the photosensitive compound for forming an optical functional layer of the present invention is unevenly distributed on the surface. It is not particularly limited as long as it has a lyophobic property to the extent that it can be used, and is used in combination when forming an optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention. It can be appropriately selected and used depending on the type of liquid compound. Examples of such a lyophobic group include a functional group containing silicon, a functional group containing fluorine, and a long-chain alkyl group having 6 to 20 carbon atoms.

  In the present invention, any of the above-mentioned lyophobic groups can be suitably used. In particular, in the present invention, the lyophobic group is a functional group containing silicon or a functional group containing fluorine. It is preferable to use a group. By having such a lyophobic group, the photosensitive compound for forming an optical functional layer of the present invention can be made more highly lyophobic. Therefore, by using the photosensitive compound for forming an optical functional layer of the present invention, This is because it is possible to produce an optical functional film having excellent optical function and low haze.

  Examples of the functional group containing silicon include a polyorganosiloxane chain represented by the following formula.

In the above formula, R ¹ and R ² each independently represents an alkyl group, an aryl group, or an alkenyl group, and m represents an integer of 2 or more.

  As the chain length of the polyorganosiloxane chain represented by the above formula, depending on the type of liquid compound used in combination when forming the optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention, The optical functional layer of the invention is not particularly limited as long as the desired liquid repellency can be imparted to the photosensitive compound. In particular, in the present invention, the m is preferably in the range of 2 to 40, particularly preferably in the range of 3 to 30, and more preferably in the range of 5 to 25.

  Specific examples of the polyorganosiloxane chain represented by the above formula include, for example, polydialkylsiloxane (eg, polydimethylsiloxane, polydiethylsiloxane, etc.), polydiarylsiloxane (eg, polydiphenylsiloxane, polyditolylsiloxane, etc.), Polyalkylaryl siloxane (eg, methylphenylsiloxane, polymethyltolylsiloxane, etc.), polyalkenylsiloxane (eg, polydivinylsiloxane, etc.), polyalkenylalkylsiloxane (eg, polyvinylmethylsiloxane, etc.), polyalkenylaryl siloxane (eg, Polyvinylphenylsiloxane, etc.).

  In the present invention, any of these polyorganosiloxane chains can be suitably used. Among them, polydialkylsiloxane chains are preferably used, and polydimethylsiloxane chains are most preferably used. This is because the degree of lyophobicity of the dimethylsiloxane chain can be arbitrarily adjusted by changing the chain length.

  As the chain length of the polyorganosiloxane chain used in the present invention, depending on the type of liquid compound used in combination when forming the optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention, It will not specifically limit if it is a range which can provide desired lyophobic property to the optical function layer photosensitive compound of this invention. Among them, the polyorganosiloxane chain used in the present invention preferably has a molecular weight in the range of 200 to 10,000, particularly preferably in the range of 500 to 5000, and more preferably in the range of 1000 to 3000. preferable.

  On the other hand, examples of the functional group containing fluorine that can be suitably used in the present invention include a fluoroalkyl chain.

  The fluoroalkyl chain used in the present invention is an optical functional layer according to the present invention depending on the type of liquid compound used in combination when forming the optical functional layer using the photosensitive compound for forming an optical functional layer according to the present invention. There is no particular limitation as long as the desired lyophobic property can be imparted to the photosensitive compound. Therefore, the fluoroalkyl group used in the present invention may be linear or branched.

  Further, the chain length of the fluoroalkyl chain used in the present invention is also determined depending on the type of liquid compound used in combination when forming the optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention. The optical functional layer of the invention is not particularly limited as long as the desired liquid repellency can be imparted to the photosensitive compound. Among them, the fluoroalkyl chain used in the present invention preferably has 1 to 20 carbon atoms, particularly preferably 3 to 18 carbon atoms, and more preferably 6 to 12 carbon atoms. preferable.

Specific examples of the linear fluoroalkyl chain used in the present invention include, for example, —CF ₂ CF ₃ , —CF ₂ (CF ₂ ) ₂ CF ₃ , —CF ₂ (CF ₂ ) ₃ CF ₃ , —CF ₂ (CF ₂ ) ₄ CF ₃ , —CF ₂ (CF ₂ ) ₅ CF ₃ , —CF ₂ (CF ₂ ) ₆ CF ₃ , —CF ₂ (CF ₂ ) ₇ CF ₃ , —CF ₂ (CF ₂ ) ₈ CF ₃ , —CF ₂ (CF ₂ ) ₉ CF ₃ , —CF ₂ (CF ₂ ) ₁₀ CF ₃ , —CH ₂ CF ₃ , —CH ₂ CF ₂ CF ₃ , —CH ₂ (CF ₂ ) ₂ CF ₃ , _{-CH 2 (CF 2) 3 CF} 3, -CH 2 (CF 2) 4 CF 3, -CH 2 (CF 2) 5 CF 3, -CH 2 (CF 2) 6 CF 3, -CH 2 (CF 2 ) ₇ CF ₃ , —CH ₂ (CF ₂ ) ₈ CF ₃ , —CH ₂ (CF ₂ ) ₉ CF ₃ , —CH ₂ (CF ₂ ) ₁₀ CF ₃ , —CH ₂ (CF ₂ ) ₁₁ CF ₃ , —CH ₂ (CF ₂ ) ₂ H, —CH ₂ (CF _{2) ) 4 H, -CH 2 CH 2} (CF 2) 2 CF 3, -CH 2 CH 2 CF 3, -CH 2 CH 2 CF 2 CF 3, -CH 2 CH 2 (CF 2) 2 CF 3, -CH ₂ CH ₂ (CF ₂ ) ₃ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₄ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₅ CF ₃ , —CH ₂ CH ₂ (CF ₂ ) ₆ CF ₃ , _{-CH 2 CH 2 (CF 2)} 7 CF 3, -CH 2 CH 2 (CF 2) 8 CF 3, -CH 2 CH 2 (CF 2) 9 CF 3, -CH 2 CH 2 (CF 2) 10 CF _{3, -CH 2 CH 2 (CF} 2) 11 C _{3, -CH 2 CH 2 (CF} 2) may be mentioned 12 CF ₃ and the like.

Specific examples of the branched fluoroalkyl chain used in the present invention include, for example, —CH (CF ₃ ) ₃ , —CH ₂ CF (CF ₃ ) ₃ , —CH (CH ₃ ) CF ₂ CF _3. , —CH (CH ₃ ) (CF ₃ ) ₂ CF ₂ H, and the like.

Furthermore, examples of the fluoroalkyl chain used in the present invention other than those described above include alicyclic structures (preferably 5-membered or 6-membered rings such as perfluoroalkyl groups, perfluorocyclopentyl groups, or alkyls substituted therewith. has a group, etc.) _{and, -CH 2 OCH 2 CF 2 CF} 3, -CH 2 CH 2 OCH 2 (CF 2) 2 CF 3, -CH 2 CH 2 OCH 2 (CF 2) 3 CF 3, -CH ₂ CH ₂ OCH ₂ (CF ₂ ) ₄ CF ₃ , —CH ₂ CH ₂ OCH ₂ (CF ₂ ) ₅ CF ₃ , —CH ₂ CH ₂ OCH ₂ (CF ₂ ) ₇ CF ₃ , —CH ₂ CH ₂ OCH _{2 (CF 2) 11 CF 3,} CH 2 CH 2 OCF 2 CF 2 OCF 2 CF 2 may include those having an ether bond such as H.

2. Next, the photoreactive group used in the photosensitive compound for forming an optical functional layer of the present invention will be described. The photoreactive group used in the present invention causes a photoreaction when irradiated with polarized ultraviolet rays, and is a liquid crystal used in combination when forming the optical functional layer using the photosensitive compound for forming an optical functional layer of the present invention. It has a function of expressing orientation with respect to materials and the like.

  The photoreactive group used in the present invention is not particularly limited as long as it can generate a photochemical reaction when irradiated with ultraviolet rays having a specific wavelength and can impart orientation to a liquid crystal material or the like. Examples of the photochemical reaction include photodimerization, photoisomerization and the like. Examples of such photoreactive groups include cinnamate group, cinnamoyl group, coumarin group, benzylidenephthalimidine, benzylideneacetophenone, diphenylacetylene, stilbazole, Examples include uracil, quinolinone, maleimide, or cinnamylideneacetic acid derivatives. Especially in this invention, it is preferable to use the photoreactive group represented by following formula (1)-(3).

In the above formulas (1) to (3), R ¹¹ , R ¹² , and R ¹³ are each independently a functional group that may be substituted, and the functional group may be an alkyl that may have a substituent. Group (preferably a linear or branched alkyl group having 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, 2-propyl, n-butyl, isobutyl, tert-butyl group, etc.); An alkenyl group which may have a substituent (for example, an alkenyl group having 1 to 8 carbon atoms, such as vinyl, allyl, 1-butenyl group, etc.); An alkynyl group (for example, an alkynyl group having 1 to 8 carbon atoms, such as ethynyl and propargyl groups); an aralkyl group (for example, an alkynyl group having 1 to 8 carbon atoms) which may have a substituent. An alkyl group which may have a substituent (preferably an alkoxy group having 1 to 8 carbon atoms which may have a substituent, for example, Methoxy, ethoxy, butoxy groups, etc.); an aryloxy group which may have a substituent (preferably an aromatic hydrocarbon group or a heterocyclic group, such as phenyloxy, 1-naphthyl) Oxy, 2-naphthyloxy, pyridyloxy, thienyloxy group, etc.); carboxyl group; cyano group; hydroxyl group; mercapto group; halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom); substituent An aromatic hydrocarbon ring group or an aromatic heterocyclic group (preferably a 5- or 6-membered monocyclic or bi-fused ring, An aromatic hydrocarbon ring or an aromatic heterocyclic ring, for example, a phenyl group, a naphthyl group, a thienyl group, a furyl group, a pyridyl group, etc.).
R ¹⁴ is a linking group which may be substituted, and the linking group is an alkylene chain which may have a substituent (preferably a linear or branched alkylene chain having 1 to 8 carbon atoms; Examples include methylene, ethylene, n-propylene, 2-propylene, n-butylene, isobutylene, etc.); an aryleneoxy group (preferably an aromatic hydrocarbon group or a heterocyclic group) which may have a substituent. For example, phenyleneoxy, 1-naphthyleneoxy, 2-naphthyleneoxy, etc.); an aromatic hydrocarbon ring chain or an aromatic heterocyclic chain which may have a substituent (preferably 5 or 6-membered, monocyclic or bicondensed aromatic hydrocarbon rings or aromatic heterocyclic rings such as phenyllene, naphthyllene, thienyllene, Ren, pyridylene, etc.).

  In addition, as each of the above-described functional groups and each linking group may have an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms, such as a methyl group, an ethyl group, 2- A propyl group, etc.); an aromatic hydrocarbon group unsubstituted or substituted with an alkyl group (for example, a phenyl group, a tolyl group, a mesityl group, etc.); an alkoxy group (preferably having a carbon number of 1 to 8 is an alkoxy group such as methoxy, ethoxy, butoxy, etc.) Halogen atoms (for example, fluorine, chlorine, bromine, iodine).

  In the present invention, any of these photoreactive groups can be suitably used, and among these, photoreactive groups represented by the following formulas (4) to (6) are preferably used.

In the above formulas (4) to (6), R ²¹ and R ²² are each independently a functional group which may be substituted, and the functional group may be a hydrogen group or an alkyl which may have a substituent. Group (preferably a linear or branched alkyl group having 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, 2-propyl, n-butyl, isobutyl, tert-butyl group, etc.); An alkoxy group which may have a substituent (preferably an alkoxy group having 1 to 8 carbon atoms which may have a substituent, such as methoxy, ethoxy and butoxy groups); a carboxyl group Cyano group; hydroxyl group; mercapto group; halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom); aromatic hydrocarbon ring group or aromatic heterocycle optionally having substituent (s) (Preferably, it is an aromatic hydrocarbon ring or aromatic heterocyclic ring which is a 5- or 6-membered monocyclic or double condensed ring. For example, a phenyl group, a naphthyl group, a thienyl group, a furyl group, a pyridyl group, etc. Can be mentioned).

R ²³ is a linking group which may be substituted, and the linking group may be an alkylene chain which may have a substituent (preferably a linear or branched alkylene chain having 1 to 8 carbon atoms; For example, methylene, ethylene, n-propylene, 2-propylene, n-butylene, isobutylene, etc.); an aromatic hydrocarbon ring chain or an aromatic heterocyclic chain which may have a substituent (preferably, A 5- or 6-membered, monocyclic or bicondensed aromatic hydrocarbon ring or aromatic heterocyclic ring, such as phenyllene, naphthyllene, thienyllene, furylene, pyridylene and the like. it can.

  The above-mentioned functional groups and linking groups may have an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms such as methyl group, ethyl group, 2-propyl group). An aromatic hydrocarbon group that is unsubstituted or substituted with an alkyl group (for example, phenyl group, tolyl group, mesityl group, etc.); a halogen atom (for example, fluorine atom, chlorine atom, bromine) Atom, iodine atom).

  Moreover, the photo-alignment group used in the present invention may have a mesogenic structure. Since the photoreactive group used in the present invention has a mesogenic structure, it is possible to produce an optical functional film having further excellent optical function using the photosensitive compound for forming an optical functional layer of the present invention. Because it becomes.

  As a photoreactive group which has such a mesogen structure, what is represented by following formula (7)-(13) can be mentioned, for example.

  In the above formulas (7) to (13), X and Y are each independently None, —O—, —CO—O—, —O—CO—, —NH—, —NH—CO—, —CH═. A group selected from CH-, -C≡C-, and -O-CO-O- is shown. Z represents a photoreactive group.

  In the above formulas (7) to (13), Z is preferably a photoreactive group represented by the above formulas (1) to (3), and further represented by (4) to (6). More preferred is a photoreactive group.

3. Photosensitive compound for forming an optical functional layer The structure of the photosensitive compound for forming an optical functional layer of the present invention is as long as it has at least one photoreactive group and one lyophobic group in the molecule. It is not particularly limited. Therefore, the structure of the photosensitive compound for forming an optical functional layer of the present invention may be a structure having one each of the photoreactive group and the lyophobic group. A structure having a plurality of one of the lyophobic groups may be used, or a structure having a plurality of both the photoreactive group and the lyophobic group may be used.

  Examples of the photosensitive compound for forming an optical functional layer of the present invention include those represented by the following formulas (I) to (IV).

  In the above formulas (I) to (IV), A is the above-described lyophobic group, and B is the above-described photoreactive group (excluding those having a mesogenic structure). C is a photoreactive group having the mesogenic structure described above. Furthermore, S is a linear or branched spacer group, which may be a divalent or higher valent organic group, such as a linear or branched group such as —C— or —C—C—. And an aromatic hydrocarbon chain such as a linear alkyl chain, a phenylene chain and a naphthalene chain, a heterocyclic aromatic chain such as pyridylene and thioferene, and a typical element branching group such as an amino group, a silyl group and a boryl group.

  In the above formulas (I) to (IV), B is preferably represented by the above formulas (1) to (3), and C is represented by the above formulas (7) to (13). It is preferable.

  In the present invention, any of the photosensitive compounds for forming an optical functional layer represented by the above formulas (I) to (IV) can be suitably used, and among them, the following formulas (V) to (XII) It is preferable to use a photosensitive compound for forming an optical functional layer represented by the following formulas (IX) to (XII).

In the above formulas (V) to (XII), A is the above-described hydrophobic group, and B is the above-described photoreactive group (excluding those having a mesogenic structure). C is a photoreactive group having the mesogenic structure described above.
X and Y are each independently none, —O—, —CO—O—, —O—CO—, —NH—, —NH—CO—, —CH═CH—, —C≡C—, It is a group selected from —O—CO—O—.

  The photosensitive compound for forming an optical functional layer of the present invention is a copolymer in which a segment containing the lyophobic group is present in the polymer main chain, or a photoreactive monomer having the photoreactive group and the lyophobic liquid. It may be a copolymer with a lyophobic monomer having a functional group. By having such a structure, for example, by appropriately changing the ratio of the photoreactive group to the lyophobic group, the lyophobic property exhibited by the photosensitive compound for forming an optical functional layer of the present invention is improved. This is because it can be easily adjusted arbitrarily according to the specific use of the photosensitive compound for forming an optical functional layer of the present invention.

  Examples of the copolymer having a segment containing the lyophobic group in the polymer main chain include a block copolymer having a dimethylsiloxane block in the main chain portion. Examples of the method for producing such a polydimethylsiloxane block copolymer include a polymer initiator method and a polymer chain transfer method.

  The polymer initiator method is a method of polymerizing the photoreactive monomer using, for example, a polydimethylsiloxane compound having a radical capable of generating an azo group or a peroxy group. Here, as a polydimethylsiloxane which has the said azo group, what is represented by a following formula can be illustrated, for example.

  When using the photoreactive compound for forming an optical functional layer of the present invention having a structure in which the photoreactive monomer having the photoreactive group and the lyophobic monomer having the lyophobic group are copolymerized, The form of copolymerization may be random copolymer, block copolymer, or graft copolymer.

  Further, as the photosensitive compound for forming an optical functional layer of the present invention, a compound having a structure in which the photoreactive monomer having the photoreactive group and the lyophobic monomer having the lyophobic group are copolymerized is used. In this case, the lyophobic monomer may be a monomer having the lyophobic group in a portion that becomes a side chain after polymerization, or a monomer having the lyophobic group in a portion that becomes a main chain after polymerization. It may be.

  On the other hand, the photoreactive monomer is not particularly limited as long as it has at least one photoreactive group and can be copolymerized with a lyophobic monomer described later. The photoreactive monomer used in the present invention may have one photoreactive group or may have a plurality of photoreactive groups.

  As a photoreactive monomer used for this invention, what is represented by a following formula can be illustrated, for example.

In the above formula, Z ¹ represents the photoreactive group. R ³¹ represents hydrogen or a methyl group. Furthermore, r represents an integer of 0 to 20, and s represents 0 or 1.

  On the other hand, the lyophobic monomer is not particularly limited as long as it has at least one lyophobic group and can be copolymerized with the photoreactive monomer. The lyophobic monomer used in the present invention may have one of the lyophobic groups or may have a plurality of lyophobic groups.

  Examples of the lyophobic monomer used in the present invention include a monomer having a dimethylsiloxane chain and a (meth) acryloyl group in the molecule, or a (meth) acrylic acid moiety or a fully fluorinated alkyl ester derivative. .

  As a lyophobic monomer used for this invention, what is represented by a following formula can be illustrated, for example.

In the above formula, R ⁴¹ represents hydrogen or methyl. ^R42 represents a methyl group or a butyl group. Furthermore, t represents an integer of 2 to 150, and u represents an integer of 1 to 20.

  As a photosensitive compound for optical function layer formation of this invention which has the structure which the said photoreactive monomer and the said lyophobic monomer copolymerized, what is represented by a following formula can be illustrated, for example.

上記式において、また、Ｒ^５１、Ｒ^５２、Ｒ^５４、Ｒ^５５は、水素、または、メチル基を表す。Ｒ^５３はメチル基またはブチル基を表す。ｖは１〜２０の整数を表し、ｗは２〜１５０の整数を表す。Ｚ^２は上記光反応性基を表す。

In the above formula, R ⁵¹ , R ⁵² , R ⁵⁴ , and R ⁵⁵ each represent hydrogen or a methyl group. R ⁵³ represents a methyl group or a butyl group. v represents an integer of 1 to 20, and w represents an integer of 2 to 150. Z ² represents the photoreactive group.

  As the photosensitive compound for forming an optical functional layer of the present invention having a structure in which the photoreactive monomer and the lyophobic monomer are copolymerized, the photoreactive monomer and the lyophobic monomer are the present invention. The entire photosensitive compound for forming an optical functional layer is not particularly limited as long as it is copolymerized at a copolymerization ratio such that a desired lyophobic property can be expressed. Especially, as a photosensitive compound for optical function layer formation of this invention, the copolymerization ratio (molar ratio) of the said photoreactive monomer and the said lyophobic monomer is 50: 50-99.9: 0.1. In the range of 80:20 to 99.8: 0.2, more preferably in the range of 90:10 to 99: 1. This is because when the copolymerization ratio (molar ratio) is within the above range, the amount of the photosensitive compound for forming the optical functional layer can be secured, and sufficient alignment regulating force of the crosslinkable liquid crystal material can be obtained.

  In addition, the photosensitive compound for forming an optical functional layer of the present invention having a structure in which the photoreactive monomer and the lyophobic monomer are copolymerized is desired as the entire photosensitive compound for forming an optical functional layer of the present invention. Any photoreactive monomer or photoreactive monomer copolymerizable with the above photoreactive monomer or the above liquidphobic monomer can be used as long as it can exhibit liquidphobic properties and can obtain a sufficient alignment regulating force of the crosslinkable liquid crystal material. Copolymers containing monomers other than liquid monomers may also be used.

B. Next, the composition for forming an optical functional layer of the present invention will be described. The composition for forming an optical functional layer of the present invention comprises the above-mentioned photosensitive compound for forming an optical functional layer according to the present invention and a crosslinkable liquid crystal material having a crosslinkable functional group.

  Since the composition for forming an optical functional layer of the present invention contains the photosensitive compound for forming an optical functional layer according to the present invention, the optical functional layer is formed by coating the composition for forming an optical functional layer of the present invention. In this case, an optical functional layer in which the photosensitive compound for forming an optical functional layer is unevenly distributed on the surface can be formed. For this reason, in the optical functional layer formed using the composition for forming an optical functional layer of the present invention, the alignment of the crosslinkable liquid crystal material is inhibited by the presence of the photosensitive compound for forming an optical functional layer. Can be reduced. For this reason, according to the present invention, it is possible to form an optical functional layer having excellent optical function and low haze.

  The reason why the present invention can form an optical functional layer having excellent optical function and low haze is the same as the reason described in the above section “A. Photosensitive compound for forming an optical functional layer”. Explanation here is omitted.

The composition for forming an optical functional layer of the present invention includes at least the photosensitive compound for forming an optical functional layer according to the present invention and the crosslinkable liquid crystal material, and has other configurations as necessary. You may do it.
Hereinafter, each structure used for the composition for optical function layer formation of this invention is demonstrated in order.

  The photosensitive compound for forming an optical functional layer used in the present invention is the same as that described in the above section “A. Photosensitive compound for forming an optical functional layer”, and thus the description thereof is omitted here. .

1. Crosslinkable liquid crystal material First, the crosslinkable liquid crystal material used in the present invention will be described. The crosslinkable liquid crystal material used in the present invention has a crosslinkable functional group.

  The crosslinkable liquid crystal material used in the present invention is not particularly limited as long as a desired optical function can be imparted to the optical functional layer produced using the optical functional layer forming composition of the present invention. Any compound having liquid crystallinity can be used. Among them, in the present invention, it is preferable to use a material exhibiting a nematic phase as the crosslinkable liquid crystal material. This is because nematic liquid crystals are easily arranged regularly as compared with liquid crystal materials exhibiting other liquid crystal phases.

The crosslinkable functional group possessed by the crosslinkable liquid crystal material used in the present invention is not particularly limited as long as it can form intermolecular crosslinks. Examples of such a crosslinkable functional group include a radiation crosslinkable functional group that forms a crosslink by radiation such as ultraviolet rays and electron beams, and a heat crosslinkable functional group that forms a crosslink by the action of heat. Among these, in the present invention, the above-mentioned radiation crosslinkable functional group is preferable, and an ultraviolet crosslinkable functional group that forms a crosslink by irradiation with ultraviolet rays is particularly preferable. The reason is as follows.
That is, when the thermally crosslinkable functional group is used as the crosslinkable liquid crystal material, for example, when the optical functional layer is formed by applying and drying the optical functional layer forming composition of the present invention, The crosslinkable liquid crystal material is cross-linked, and as a result, a desired optical function may not be imparted to the optical functional layer formed. However, this is because there are few such problems with the ultraviolet crosslinkable functional group. Further, the use of an ultraviolet crosslinkable functional group has an advantage that the step of crosslinking the crosslinkable liquid crystal material can be completed in a short time.

  The UV crosslinkable functional group is usually a polymerizable functional group capable of forming a crosslink by irradiating ultraviolet rays and obtaining a polymer compound of the crosslinkable liquid crystal material, or crosslinked by irradiating ultraviolet rays. A dimerization functional group that can form a dimer of the crosslinkable liquid crystal material is used.

  Examples of the polymerizable functional group include acryloyl group, methacryloyl group, vinyl ether group, oxetanyl group, glycidyl group, and alicyclic epoxy group.

  Examples of the dimerization functional group include cinnamate derivatives, coumarin derivatives, chalcone derivatives, benzylidenephthalimidine derivatives, benzylideneacetophenone derivatives, diphenylacetylene derivatives, stilbazole derivatives, uracil derivatives, quinolinone derivatives, thymine derivatives, maleinimide derivatives. And cinnamylideneacetic acid derivatives.

  In the present invention, any of the polymerizable functional group and the dimerized functional group can be preferably used, and among them, the polymerizable functional group is preferably used. This is because the polymerizable functional group has a high reaction rate when a photopolymerization initiator is added, and a highly durable layer can be formed with a smaller amount of UV irradiation than the dimerized functional group.

  In the present invention, it is preferable to use an acryloyl group or an oxetanyl group among the polymerizable functional groups. This is because these polymerizable functional groups are excellent in reactivity. Furthermore, in the present invention, it is preferable to use an acryloyl group among these polymerizable functional groups. This is because the crosslinkable liquid crystal material having an acryloyl group is easy to apply to the present invention because there are many types that are industrially available.

  The crosslinkable liquid crystal material used in the present invention may have a plurality of the crosslinkable functional groups or may have only one. In the present invention, a crosslinkable liquid crystal material having a plurality of crosslinkable functional groups and a crosslinkable liquid crystal material having only one crosslinkable functional group may be mixed and used.

  Among the crosslinkable liquid crystal materials having such a structure, examples of those having a plurality of the crosslinkable functional groups include compounds represented by the following formulas (a) to (g).

  Moreover, as what has only one said crosslinkable functional group among the crosslinkable liquid crystal materials which have such a structure, the compound represented by following formula (h) and (i) can be mentioned, for example.

Here, in the above formulas (a) to (i), L ¹ and L ² each independently represent —O— or —O—CO—O—. D represents a mesogenic group represented by the following formulas (i) to (viii).

R ⁶¹ each independently represents hydrogen or a methyl group. a to i are each independently an integer of 2 to 12, more preferably 4 to 10.
Further, L ³ and L ⁴ each independently represent any of the following formulas (ix) to (xiii).

J represents an integer of 0 to 20. R ⁶³ represents hydrogen, chlorine, bromine, iodine, an alkyl group having 1 to 10 carbon atoms, an alkyloxycarbonyl group, an alkoxy group, a cyano group, or a nitro group.

  In addition to the above, specific examples of the crosslinkable liquid crystal material used in the present invention include, for example, JP-A-4-227684, JP-A-9-111240, JP-A-10-182556, JP-A-11-513019. No. 2000-98113, No. 2002-69450, No. 2002-30042, No. 2003-96066, and No. 2004-123597. Can be mentioned.

  The crosslinkable liquid crystal material used in the present invention may be one kind or a mixture of two or more kinds.

2. Optical functional layer forming composition The optical functional layer forming composition of the present invention contains the above-mentioned photosensitive material for forming an optical functional layer and the above-mentioned crosslinkable liquid crystal material, but for forming the optical functional layer of the present invention. The ratio of the photosensitive compound for forming an optical functional layer contained in the composition to the crosslinkable liquid crystal material is within a range that can give a predetermined optical function to the optical functional layer produced according to the present invention. It is not particularly limited. Especially in this invention, it is preferable that content of the said photosensitive compound for optical function layer formation with respect to 100 mass parts of said crosslinkable liquid crystal materials exists in the range of 0.001 mass part-10 mass parts, especially 0. It is preferably within a range of 0.01 parts by mass to 1 part by mass, and more preferably within a range of 0.01 parts by mass to 0.5 parts by mass. When the content of the photosensitive compound for forming an optical functional layer is less than the above range, for example, in the optical functional layer formed using the composition for forming an optical functional layer of the present invention, the crosslinkable liquid crystal material is ordered. This is because it may be difficult to arrange them periodically. Moreover, it is because there exists a possibility that a desired optical function may not be provided to the optical function layer formed using the composition for optical function layer formation of this invention when more than the said range.

  In the composition for forming an optical functional layer of the present invention, the content of the photosensitive compound for forming an optical functional layer is preferably 1% by mass or less, particularly 0.001% by mass with respect to the total solid content ratio. % To 0.5% by mass, and particularly preferably 0.01% to 0.1% by mass. This is because when the content is within the above range, an optical functional layer having a smaller haze can be formed using the composition for forming an optical functional layer of the present invention.

  The composition for forming an optical functional layer of the present invention contains the above-mentioned photosensitive material for forming an optical functional layer and the above-mentioned crosslinkable liquid crystal material, but contains other components as necessary. There may be. Examples of such other configurations include solvents, photopolymerization initiators, polymerization inhibitors, plasticizers, surfactants, and silane coupling agents. In particular, in the present invention, it is preferable to use a photopolymerization initiator and a solvent as the other configuration. When the optical functional layer forming composition of the present invention contains a solvent, when the optical functional layer forming composition of the present invention is applied to form the optical functional layer, the optical functional layer forming photosensitive property is formed. This is because an optical functional layer in which the compound is unevenly distributed on the surface can be formed. Moreover, when the optical functional layer is formed using the composition for forming an optical functional layer of the present invention by containing a photopolymerization initiator in the composition for forming an optical functional layer of the present invention, the crosslinkable liquid crystal is used. This is because the cross-linking reaction of the material can be promoted.

  The solvent used in the present invention is not particularly limited as long as it can dissolve the optical functional layer-forming photosensitive compound and the crosslinkable liquid crystal material at a desired concentration. Examples of such solvents include ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and cyclopentanone; hydrocarbon solvents such as benzene, toluene and hexane; ethers such as tetrahydrofuran and 1,2-dimethoxyethane. Solvents; alkyl halide solvents such as chloroform and dichloromethane; ester solvents such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate and propylene glycol monomethyl ether acetate; amide solvents such as N, N-dimethylformamide; and dimethyl Examples thereof include, but are not limited to, sulfoxide solvents such as sulfoxide.

  Further, the solvent used in the present invention may be one kind or a mixed solvent of two or more kinds of solvents.

  In addition, when a solvent is contained in the composition for forming an optical functional layer of the present invention, the solid content concentration of the composition for forming an optical functional layer of the present invention is not particularly limited, and for forming the optical functional layer of the present invention. When forming an optical functional layer using a composition, it can be made into arbitrary density | concentrations according to the coating method etc. which apply the composition for optical functional layer formation of this invention.

  On the other hand, as a photoinitiator used for this process, it can select suitably according to the kind etc. of the polymerizable functional group which the said crosslinkable liquid crystal material has, and can use. In particular, in the present invention, when a crosslinkable liquid crystal material having an acryloyl group and a methacryloyl group is used as the polymerizable functional group, it is preferable to use a radical photopolymerization initiator. In the case of using a crosslinkable liquid crystal material having a vinyl ether group, an oxetanyl group, a glycidyl group, and an alicyclic epoxy group, it is preferable to use a photocationic polymerization initiator.

  Examples of the photo radical polymerization initiator include benzyl, benzoin isobutyl ether, benzoin isopropyl ether, benzophenone, benzoyl benzoic acid, methyl benzoyl benzoate, 4-benzoyl-4′-methyldiphenyl sulfide, benzyl methyl ketal, dimethylaminomethyl. Benzoate, 2-n-butoxyethyl-4-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, 3,3′-dimethyl-dimethyl-4-methoxybenzophenone, methylobenzoylformate, 2-methyl-1- ( 4- (methylthio) phenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, 1-hydroxycyclohexyl Erniketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-chlorothioxanthone, 2,4- Diethylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 1-chloro-4-proxythioxanthone, 2-hydroxy-2-methyl- [4- (1-methylvinyl) phenyl] propanol oligomer Etc.

  Examples of the cationic photopolymerization initiator include sulfonic acid esters, imide sulfonates, dialkyl-4-hydroxysulfonium salts, arylsulfonic acid-p-nitrobenzyl esters, silanol-aluminum complexes, (η6-benzene) (η5-cyclo Pentadienyl) iron (II) and the like. More specifically, benzoin tosylate, 2,5-dinitrobenzyl tosylate, N-tosicphthalimide and the like can be mentioned.

  Furthermore, examples of the compound that can be used as the photo radical polymerization initiator and the photo cation polymerization initiator include aromatic iodonium salts, aromatic sulfonium salts, aromatic diazonium salts, aromatic phosphonium salts, triazine compounds, An iron arene complex etc. can be illustrated. More specifically, chlorides with or without iodine such as diphenyliodonium, ditolyliodonium, bis (p-tert-butylphenyl) iodonium, bis (p-chlorophenyl) iodonium; bromide, borofluoride, hexafluorophosphate salt, Iodonium salts such as hexafluoroantimonate salts, chlorides of sulfonium such as triphenylsulfonium, 4-tert-butyltriphenylsulfonium, tris (4-methylphenyl) sulfonium, bromides, borofluorides, hexafluorophosphate salts, hexafluoro Sulfonium salts such as antimonate salts, 2,4,6-tris (trichloromethyl) -1,3,5-triazine, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2 − And the like Chiru 4,6-bis (trichloromethyl) -1,3,5-2,4,6-substituted-1,3,5-triazine compounds such as triazines.

  Moreover, when using the said photoinitiator for the composition for optical function layer formation of this invention, a photoinitiator adjuvant can be used together. Examples of such photopolymerization initiation assistants include tertiary amines such as triethanolamine and methyldiethanolamine, and benzoic acid derivatives such as ethyl 2-dimethylaminoethylbenzoate and ethyl 4-dimethylamidebenzoate. Yes, but not limited to these.

  When the photopolymerization initiator is used in the composition for forming an optical functional layer of the present invention, the addition amount thereof is in the range of 0.01% by mass to 20% by mass with respect to the mass of the crosslinkable liquid crystal material. In particular, it is preferably in the range of 0.1% by mass to 10% by mass, particularly preferably in the range of 0.3% by mass to 5% by mass. If the addition amount of the photopolymerization initiator is less than the above range, the amount of ultraviolet irradiation necessary to crosslink the crosslinkable liquid crystal material may increase too much. It is because there exists a possibility of inhibiting the reaction of the photosensitive compound for optical function layer formation.

C. Next, the optical functional film of the present invention will be described. The optical functional film of the present invention comprises a transparent substrate, a reaction product of the photosensitive compound for forming an optical functional layer according to the present invention, and a crosslinkable liquid crystal material having a crosslinkable functional group, formed on the transparent substrate. An optical functional film having an optical functional layer containing a crosslinked product, wherein the reaction product of the photosensitive compound for forming an optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate. It is characterized by being.

Such an optical functional film of the present invention will be described with reference to the drawings. FIG. 2 is a schematic view showing an example of the optical functional film of the present invention. As illustrated in FIG. 2, the optical functional film 10 of the present invention is formed on the transparent substrate 1, the reaction product A of the photosensitive compound for forming the optical functional layer, and the crosslinkable liquid crystal material. And an optical functional layer 2 containing a product.
In such an example, the optical functional film 10 of the present invention is such that the reaction product A of the photosensitive compound for forming an optical functional layer contained in the optical functional layer 2 is the same as the transparent substrate 1 of the optical functional layer 2. Is unevenly distributed on the opposite surface.

  According to the present invention, the reaction product of the photosensitive compound for forming an optical functional layer in the optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate. Since it is possible to prevent the alignment of the cross-linked product of the cross-linkable liquid crystal material from being inhibited by the presence of the reaction product of the layer-forming photosensitive compound, an optical functional film having excellent optical function and low haze is obtained. be able to.

The optical functional film of the present invention has at least the transparent substrate and the optical function, and may have other configurations as necessary.
Hereafter, each structure used for the optical function film of this invention is demonstrated in order.

1. Optical Functional Layer First, the optical functional layer used in the present invention will be described. The optical functional layer used in the present invention includes a reaction product of the photosensitive compound for forming an optical functional layer according to the present invention and a crosslinked product of the crosslinkable liquid crystal material. The active compound is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate.

(1) Reaction product of photosensitive compound for forming optical functional layer First, the reaction product of the photosensitive compound for forming an optical functional layer will be described. The reaction product of the photosensitive compound for forming an optical functional layer used in the present invention is irradiated with polarized ultraviolet rays to the photosensitive compound for forming an optical functional layer according to the present invention, and the photoreaction of the photosensitive compound for forming an optical functional layer is performed. It is a reaction result obtained by the reaction of the sex group. Therefore, for example, when the photoreactive group of the composition for forming an optical functional layer according to the present invention causes a photodimerization reaction when irradiated with polarized ultraviolet rays, the photosensitivity for forming an optical functional layer is used. The reaction product of the compound is a compound in which the photosensitive compound for forming an optical functional layer having a plurality of photoreactive groups forms a crosslinked structure.

  The photosensitive compound for forming an optical functional layer is the same as that described in the section “A. Photosensitive compound for forming an optical functional layer”, and thus the description thereof is omitted here.

(2) Crosslinked product of crosslinkable liquid crystal material Next, a crosslinked product of the crosslinkable liquid crystal material used in the present invention will be described. The cross-linked product of the cross-linkable liquid crystal material used in the present invention is a result obtained by forming a cross-link by the cross-linkable liquid crystal material having a cross-linkable functional group.

When a crosslinkable liquid crystal material having a polymerizable functional group is used as the crosslinkable functional group, the crosslinkable liquid crystal material is a polymer of the crosslinkable liquid crystal material. On the other hand, when a crosslinkable liquid crystal material having a dimerization functional group is used as the crosslinkable functional group, the dimerization functional group in the molecule becomes a dimer in the case of one of the dimerization functional groups in the molecule. When there is a plurality, the cross-linked product is obtained.
Here, since the crosslinkable liquid crystal material is the same as that described in the section “B. Composition for forming optical functional layer”, description thereof is omitted here.

  The cross-linked product of the cross-linkable liquid crystal material exists in a regularly arranged state by the action of the reaction product of the photosensitive compound for forming an optical functional layer, and the arrangement state includes the optical function of the present invention. There is no particular limitation as long as the film is in an arrangement state in which a desired optical function can be expressed. Examples of such an arrangement state include a state in which the mesogens are parallel to the transparent substrate and the average orientation direction is oriented in a specific direction in the plane. This liquid crystal structure is called a homogeneous structure (parallel alignment structure). By having such a structure, the optical function film of the present invention can be optically imparted with properties as an A plate. Further, the mesogen can be oriented in a direction inclined with respect to the transparent substrate, and the inclination angle dependency in a specific direction of the optical functional layer can be asymmetric with respect to the normal direction.

  In addition, since the optical functional film of the present invention does not require an alignment layer, as described above, the three-dimensional liquid crystal material that has been difficult to realize with a conventional optical functional film that requires an alignment layer. Orientation can be realized.

(3) Optical functional layer In the optical functional layer used in the present invention, the reaction product of the photosensitive compound for forming an optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate. It is characterized by. Here, in the present invention, the term “distributed” means a reaction product of the photosensitive compound for forming an optical functional layer present on the surface of the optical functional layer used in the present invention on the side opposite to the transparent substrate. This means that the concentration of is higher than the concentration of the reaction product of the photosensitive compound for forming an optical functional layer present at the center in the thickness direction of the optical functional layer used in the present invention. The thickness direction means a direction perpendicular to the plane direction of the optical functional layer used in the present invention.

  In the optical functional layer used in the present invention, as an embodiment in which the reaction product of the photosensitive compound for forming an optical functional layer is unevenly distributed, the haze of the optical functional layer used in the present invention can be set to a desired level, and The embodiment is not particularly limited as long as it can exhibit a predetermined optical function. As such an embodiment, for example, in the optical functional layer, a region where the reaction product of the photosensitive compound for forming an optical functional layer is present and a region where the reactant is not present exist so as to form an interface. The concentration of the reaction product of the photosensitive compound for forming an optical functional layer may be continuously reduced from the surface opposite to the transparent substrate toward the surface on the transparent substrate side. The aspect which exists in such a manner may be sufficient.

In the optical functional layer of the present invention, when the reactant of the photosensitive compound for forming an optical functional layer is present in the latter embodiment, the optical function used in the present invention is determined as the degree of concentration gradient of the reactant. There is no particular limitation as long as the haze of the layer can be set to a desired level and a predetermined optical function can be exhibited. In particular, in the present invention, 50% or more of the total amount of the reactants present in the optical functional layer is within a range of 10% from the surface opposite to the transparent substrate, more preferably 5% to 8%. It is preferable that it exists in the range of 0.01%-0.3% more preferably. This is because when the grade of the concentration of the reactant is within the above range, it is possible to form an optical functional layer having a smaller haze by using the optical functional layer forming composition of the present invention. .
In addition, the grade of the said reaction material inclination can be calculated | required by analyzing the cross section of an optical function layer using analytical methods, such as TOF-SIMS, for example. Moreover, although it is qualitative, uneven distribution can be confirmed by measuring the film surface and the atomic composition ratio in the depth direction by photoelectron X-ray analysis.

  The optical functional layer used in the present invention is characterized in that the reaction product of the photosensitive compound for forming the optical functional layer is unevenly distributed at least on the surface of the optical functional layer opposite to the transparent substrate. To do. Therefore, in the optical functional layer used in the present invention, the reaction product of the photosensitive compound for forming the optical functional layer is unevenly distributed only on the surface of the optical functional layer opposite to the transparent substrate. Alternatively, it may be unevenly distributed on both the surface on the opposite side of the transparent substrate and the surface on the transparent substrate side.

  The content of the reaction product of the photosensitive compound for forming an optical functional layer in the optical functional layer used in the present invention is preferably 1% by mass or less, and more preferably in the range of 0.001% by mass to 0.5% by mass. It is preferable to be within the range of 0.01% by mass to 0.3% by mass. This is because when the content is within the above range, the optical function film of the present invention can have a smaller haze.

  The optical functional layer in the present invention may contain a compound other than the crosslinked product of the crosslinkable liquid crystal material and the reaction product of the photosensitive compound for forming the optical functional layer. Such other compounds are not particularly limited as long as they do not impair the alignment state of the crosslinkable liquid crystal material in the optical function layer and the optical function of the optical function layer. It can be appropriately selected and used according to the use of the optical functional film. Examples of such other compounds include a polymerization initiator, a polymerization inhibitor, a plasticizer, a surfactant, and a silane coupling agent. In particular, in the present invention, when the crosslinkable liquid crystal material is used as the liquid crystal material, it is preferable to use a polymerization initiator or a polymerization inhibitor as the other compound.

  In addition, a non-crosslinkable liquid crystal material or a non-liquid crystal compound as shown below can be added to the optical functional layer in the present invention within a range that does not impair the object of the present invention. Examples of the non-liquid crystalline compound that can be added include polyol acrylates, epoxy acrylates, urethane acrylates, polyester acrylates, and epoxy resins.

  The configuration of the optical functional layer used in the present invention is not particularly limited as long as a desired optical function can be expressed according to the use of the optical functional film of the present invention. Therefore, the optical functional layer used in the present invention may have a configuration composed of a single layer, or may have a configuration in which a plurality of layers are laminated.

The thickness of the optical functional layer in the present invention is such that the optical functional film of the present invention has a desired optical function depending on the cross-linked product of the crosslinkable liquid crystal material and the type of reaction product of the photosensitive compound for forming the optical functional layer. If it is in the range which can be provided, it will not specifically limit. In particular, in the present invention, it is preferably in the range of 0.5 μm to 10 μm, particularly preferably in the range of 0.5 μm to 5 μm, and more preferably in the range of 0.8 μm to 3 μm. preferable.
Here, when the optical functional layer has a structure in which a plurality of layers are laminated, the thickness means the sum of the thicknesses of all the layers.

2. Transparent substrate Next, the transparent substrate used in the present invention will be described. The transparent substrate used in the present invention has transparency, and supports the optical functional layer in the optical functional film of the present invention.

The transparency of the transparent substrate used in the present invention may be arbitrarily determined according to the transparency required for the optical functional film of the present invention, but it is usually preferable that the transmittance in the visible light region is 80% or more. 90% or more is more preferable. When the transmittance is in the above range, for example, when the optical functional film of the present invention is used as a viewing angle compensation film for a liquid crystal display device, it is possible to prevent the display luminance of the liquid crystal display device from being lowered. It is.
Here, the transmittance of the transparent substrate can be measured according to JIS K7361-1 (Testing method for total light transmittance of plastic transparent material).

  The transparent substrate used in the present invention may be a flexible material having flexibility or a rigid material having no flexibility such as a glass substrate as long as it has the above-described transparency. Among them, it is preferable to use a flexible material in the present invention. By using a flexible material, the process for producing the optical functional film of the present invention is performed by the Roll to Roll process (a layer for forming an optical functional layer is continuously formed on a transparent substrate unwound from a transparent substrate wound in a roll shape). This is because the optical functional film of the present invention can be manufactured with high productivity.

The transparent substrate used in the present invention may be an optically isotropic substrate or a substrate having optical functionality.
Here, the optically isotropic substrate means a transparent substrate having Re of 10 nm or less and Rth of 40 nm or less. In particular, the optically isotropic substrate used in the present invention preferably has Re of 5 nm or less. Rth is preferably 20 nm or less.

The above Re and Rth are defined by the following formulas.
Re = (nx−ny) × d
Rth = [{(nx + ny) / 2} -nz] × d
In the formula, nx is the refractive index in the direction with the highest refractive index in the in-plane direction of the transparent substrate, ny is the refractive index in the direction with the lowest refractive index in the in-plane direction of the transparent substrate, and nz is the thickness direction of the transparent substrate. Is the refractive index. D is the thickness of the transparent substrate.

  Examples of the material constituting the optically isotropic substrate include cellulose derivatives, norbornene polymers, cycloolefin polymers, polycarbonates, polyesters, and the like. Among them, the optically isotropic substrate used in the present invention is preferably made of a cellulose derivative or a cycloolefin polymer. This is because the cellulose derivative is particularly excellent in optical isotropy. Moreover, it is because a cycloolefin type polymer is excellent in durability.

  As said cellulose derivative, it is preferable to use a cellulose ester, Furthermore, it is preferable to use cellulose acylates among cellulose esters. This is because cellulose acylates are advantageous in terms of availability because they are widely used industrially.

  Moreover, as said cellulose acylates, C2-C4 lower fatty acid ester is preferable. Such a lower fatty acid ester may contain only a single lower fatty acid ester, for example, cellulose acetate, and a plurality of fatty acid esters such as cellulose acetate butyrate and cellulose acetate propionate may be used. It may be included.

In the present invention, cellulose acetate can be particularly preferably used among the above lower fatty acid esters. Moreover, as a cellulose acetate, it is most preferable to use the triacetyl cellulose whose average acetylation degree is 57.5-62.5% (substitution degree: 2.6-3.0).
Here, the degree of acetylation means the amount of bound acetic acid per unit mass of cellulose. The degree of acetylation can be determined by measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method for cellulose acetate and the like). In addition, the acetylation degree of the triacetyl cellulose which comprises a triacetyl cellulose film can be calculated | required by said method, after removing impurities, such as a plasticizer contained in a film.

  On the other hand, the cycloolefin polymer is a polymer having a monomer unit composed of a cyclic olefin (cycloolefin) such as norbornene or a polycyclic norbornene monomer. Such a cycloolefin-based polymer can control the glass transition point and water absorption rate within a preferable range by molecular design, and can satisfy good heat resistance and appropriate water absorption.

The cycloolefin polymer used in the present invention preferably has a saturated water absorption at 23 ° C. of 1% by mass or less. This is because a transparent substrate made of such a cycloolefin-based polymer is less likely to cause changes in optical properties and dimensional changes due to water absorption.
Here, the said saturated water absorption rate shall mean the value obtained by immersing in 23 degreeC water for 1 week, and measuring an increase mass based on ASTMD570.

  In addition, the cycloolefin polymer used in the present invention preferably has a glass transition temperature in the range of 100 ° C to 200 ° C. This is because a transparent substrate made of such a cycloolefin polymer is excellent in heat resistance and processability.

  Examples of the transparent substrate made of a cycloolefin polymer used in the present invention include “Topas” sold by Ticona, Germany, “Arton” sold by JSR Co., Ltd., and Nippon Zeon Co., Ltd. “ZEONOR” and “ZEONEX” sold by the company, “Apel” sold by Mitsui Chemicals, Inc., and the like.

When a substrate having optical functionality is used as the transparent substrate, such a transparent substrate is not particularly limited as long as it can impart a desired refractive index anisotropy to the optical functional film of the present invention. In particular, in the present invention, it is preferable to use a transparent substrate having properties as a λ / 4 plate or properties as a λ / 2 plate.
Here, the above-mentioned “having properties as a λ / 4 plate” usually means that Re of the transparent substrate shows a value of 1/4 of the wavelength of incident light. As the transparent substrate to be used, those having Re at a wavelength of 550 nm in the range of 120 nm to 150 nm are preferable.
Further, the above-mentioned “having properties as a λ / 2 plate” usually means that Re of the transparent substrate shows a half value of the wavelength of incident light, but is used in the present invention. The transparent substrate to be used is preferably one having Re at a wavelength of 550 nm in the range of 250 nm to 300 nm.

  The thickness of the transparent substrate used for this invention will not be specifically limited if it is in the range which can provide required self-supporting property according to the use etc. of the optical function film of this invention. Especially in this invention, it is preferable to exist in the range of 25 micrometers-1000 micrometers, and it is especially preferable to exist in the range of 30 micrometers-100 micrometers. This is because if the thickness of the transparent substrate is thinner than the above range, the necessary self-supporting property may not be imparted to the optical functional film of the present invention. Moreover, when the thickness is thicker than the above range, for example, when cutting the optical functional film of the present invention, there is a case where processing waste increases or wear of the cutting blade is accelerated.

In addition, the structure of the transparent substrate used for this invention is not restricted to the structure which consists of a single layer, You may have the structure by which the several layer was laminated | stacked.
Here, in the case of a configuration in which a plurality of layers are laminated, layers having the same composition may be laminated, or a plurality of layers having different compositions may be laminated. May be.

As a transparent substrate having a structure in which the plurality of layers are laminated, an ultraviolet ray and / or an electron beam curable resin is formed on a layer composed of the cellulose derivative, norbornene polymer, cycloolefin polymer, polycarbonate, polyester, or the like. Examples thereof include a laminate of layers cured by ultraviolet rays or electron beams.
The layer in which the ultraviolet ray and / or electron beam curable resin is cured by ultraviolet ray or electron beam serves as a shielding layer for suppressing the additive contained in the layer composed of the polymer from moving to the optical functional layer. , It plays a role of improving the adhesion between the layer composed of the polymer and the optical functional layer.

  The ultraviolet curable resin and the electron beam curable resin have two or more polymerizable groups such as a polymerizable vinyl group, allyl group, (meth) acryloyl group, isophenyl group, epoxy group, and oxetanyl group. Or what forms a crosslinked structure or network structure by irradiation of an electron beam is preferable. Among these, in this step, a (meth) acryloyl group or an epoxy group is preferable from the viewpoint of polymerization rate and reactivity, and a polyfunctional monomer or oligomer is preferable. Examples of such ultraviolet curable resins and electron beam curable resins include ultraviolet curable polyol acrylates, epoxy acrylates, urethane acrylates, polyester acrylates, and epoxy resins. These are usually used together with known photopolymerization initiators. The photopolymerization initiator or photosensitizer contained in the ultraviolet and / or electron beam curable resin composition excluding the solvent component that volatilizes after coating and drying is 0.5% by mass to 5% by mass of the composition. Is preferred.

3. Other Configurations The optical functional film of the present invention has at least the optical functional film and the transparent substrate, but may have other configurations other than these as necessary. Such other configurations are not particularly limited as long as a desired function can be imparted to the optical functional film of the present invention.

4). Optical function film The optical function of the optical function film of the present invention can be appropriately determined according to the use of the optical function film of the present invention, etc., but the properties as a λ / 4 plate, or as a λ / 2 plate It is preferable to have the following properties.
The above-mentioned “having properties as a λ / 4 plate” usually means that the optical functional film Re of the present invention exhibits a value of ¼ of the wavelength of incident light. In the optical functional film of the present invention, Re at a wavelength of 550 nm is preferably in the range of 120 nm to 150 nm.
In addition, the above-mentioned “having properties as a λ / 2 plate” usually means that Re of the optical functional film of the present invention shows a value half of the wavelength of incident light. Especially, it is preferable that Re in wavelength 550nm is in the range of 250 nm-300 nm for the optical function film of this invention.

  When the optical functional film of the present invention has the property as the λ / 4 plate or the property as a λ / 2 plate, the wavelength dispersion of Re of the optical functional film of the present invention is such that the shorter the wavelength, the more Re It may be a reverse dispersion type in which the value decreases, a forward dispersion type in which the Re value increases as the wavelength becomes shorter, or a flat type in which the Re value does not have wavelength dependency .

  The form of the optical functional film of the present invention is not particularly limited. For example, the optical functional film may have a sheet shape that matches the screen size of a liquid crystal display device using the optical functional film of the present invention, or is long. It may be a shape.

4). Use of optical functional film The use of the optical functional film of the present invention is not particularly limited, and can be used for various applications by arbitrarily controlling the optical function exhibited by the optical functional layer. Examples of such applications include optical compensation films (for example, viewing angle compensation films) used in liquid crystal display devices, elliptically polarizing plates, circularly polarizing plates, and brightness enhancement plates. Among these, the optical functional film of the present invention can be suitably used as an optical compensation film for improving the viewing angle dependency of a liquid crystal display device.

5. Production method of optical functional film The optical functional film of the present invention can be produced, for example, by the method described in the section “D. Production method of optical functional film” described later.

D. Next, a method for producing an optical functional film of the present invention will be described. The method for producing an optical functional film of the present invention is a method of forming an optical functional layer forming layer on the transparent substrate by applying the optical functional layer forming composition according to the present invention using a transparent substrate. The functional layer forming layer forming step, and the optical functional layer forming layer is irradiated with polarized ultraviolet light, and the photoreactive group is reacted to cause the optical functional layer forming layer to have orientation with respect to the crosslinkable liquid crystal material. It is characterized by having an orientation imparting step for developing, a liquid crystal alignment step for aligning the crosslinkable liquid crystal material, and a liquid crystal crosslinking step for crosslinking the crosslinkable liquid crystal material.

  Such a method for producing an optical functional film of the present invention will be described with reference to the drawings. FIG. 3 is a schematic view showing an example of a method for producing an optical functional film of the present invention. As illustrated in FIG. 3, the method for producing an optical functional film of the present invention uses a transparent substrate (FIG. 3A), and by applying the optical functional layer forming composition according to the present invention, An optical functional layer forming layer forming step for forming the optical functional layer forming layer 2 ′ on the transparent substrate 1 (FIG. 3B), and the optical functional layer forming layer 2 ′ are irradiated with polarized ultraviolet rays, An orientation imparting step (FIG. 3 (c)) for causing the optical functional layer forming layer 2 ′ to exhibit orientation with respect to the crosslinkable liquid crystal material by reacting the photoreactive group, and the retardation layer forming A liquid crystal alignment step (FIG. 3 (d)) in which the crosslinkable liquid crystal material is aligned by heating the layer 2 ′, and the crosslinkable liquid crystal is irradiated by irradiating the retardation layer forming layer 2 ′ with ultraviolet rays. The liquid crystal crosslinking step for crosslinking the material (FIG. 3 (e)) Bright substrate 1 is for producing an optical functional film 10 having an optical function layer 2 formed on the transparent substrate 1 (FIG. 3 (f)).

  According to the present invention, since the optical functional layer forming composition according to the present invention is used as the optical functional layer forming composition, an optical functional layer having excellent optical function and low haze can be obtained. An optical functional film provided can be manufactured. For this reason, according to the method for producing an optical functional film of the present invention, an optical functional film having excellent optical function and low haze can be obtained.

  The reason why the present invention can produce an optical functional film having excellent optical function and low haze is the same as the reason described in the above section “A. Photosensitive compound for forming an optical functional layer”. Explanation here is omitted.

The method for producing an optical functional film of the present invention comprises at least the layer forming step for forming an optical functional layer, the orientation imparting step, the liquid crystal aligning step, and the liquid crystal crosslinking step. May have other processes.
Hereafter, each process used for this invention is demonstrated in order.

1. First, a layer forming process for forming an optical functional layer used in the present invention will be described. This step is a step of forming an optical functional layer forming layer on the transparent substrate by applying the optical functional layer forming composition according to the present invention using a transparent substrate.

  In this step, the optical functional layer forming layer is formed by coating the optical functional layer forming composition on the transparent substrate. In this step, the optical functional layer forming composition is formed on the transparent substrate. The coating method to be coated on the top is not particularly limited as long as it is a method capable of forming a layer for forming an optical functional layer having desired flatness according to the composition of the composition for forming an optical functional layer. Absent. Examples of such coating methods include gravure coating, reverse coating, knife coating, dip coating, spray coating, air knife coating, roll coating, printing, curtain coating, die coating, and casting. Examples thereof include a method, a bar coating method, an extrusion coating method, and an E-type coating method.

  In addition, the thickness of the coating film of the composition for forming an optical functional layer is a desired optical thickness according to the present invention depending on the type of the crosslinkable liquid crystal material contained in the composition for forming an optical functional layer used in this step. It is not particularly limited as long as it is within a range where an optical functional film capable of expressing the function can be produced. In particular, in this step, it is preferably within a range of 0.1 μm to 50 μm, particularly preferably within a range of 0.5 μm to 30 μm, and in particular within a range of 0.5 μm to 10 μm. Is preferred.

  In addition, when a composition containing a solvent is used as the composition for forming an optical functional layer, the method for drying the coating film is generally used, for example, a heat drying method, a vacuum drying method, a gap drying method, or the like. A drying method can be used. In addition, the drying method in the present invention is not limited to a single method, and for example, a plurality of drying methods may be adopted in such a manner that the drying method is sequentially changed according to the amount of the remaining solvent.

2. Orientation imparting step Next, the orientation imparting step used in the present invention will be described. In this step, the optical functional layer forming layer is irradiated with polarized ultraviolet rays, and the photoreactive group of the optical functional layer forming photosensitive compound contained in the optical functional layer forming layer is allowed to react with the optical function layer forming layer. This is a step of causing the functional layer forming layer to exhibit orientation with respect to the crosslinkable liquid crystal material.

  In this step, as the polarized ultraviolet ray irradiated to the optical functional layer forming layer, the wavelength can cause a photoreaction of the photoreactive group of the optical functional layer forming photosensitive material, and The crosslinkable liquid crystal material is not particularly limited as long as it is within a range in which the crosslinkable functional group has a crosslinkable formation reaction. Such polarized ultraviolet rays can be appropriately selected and used according to the types of the photoreactive group and the crosslinkable functional group.

In the present step, the method for irradiating the optical functional layer forming layer with polarized ultraviolet rays is not particularly limited as long as the optical functional layer forming layer can be irradiated with polarized ultraviolet rays in a desired vibration direction. As such a method, a method of using a light source that oscillates ultraviolet light having a wavelength in the above range and irradiating the non-polarized ultraviolet light oscillated from the light source to the optical functional layer forming layer through a polarizer is usually used. It is done.
At this time, the vibration direction of the polarized ultraviolet light applied to the optical functional layer forming layer can be changed by changing the direction of the absorption axis of the polarizer.

  Examples of the polarizer include a Glan-Thompson prism, a Grand Taylor prism, a polarizing film containing a dichroic dye, a Brewster plate polarizer, and a wire grid polarizer.

  Examples of the light source include an ultrahigh pressure mercury lamp, a medium pressure mercury lamp, a xenon lamp, a halogen lamp, a deep UV lamp, and a fluorescent lamp.

  Furthermore, when irradiating polarized ultraviolet rays to the optical functional layer forming layer in this step, a UV cut filter that shields ultraviolet rays having a specific wavelength may be used as necessary. By using such a UV cut filter, for example, the reaction of the photosensitive compound for forming an optical functional layer is prevented from being inhibited, or the crosslinking formation reaction of the crosslinking liquid crystal material proceeds in this step. This is because it can be prevented.

As a UV cut filter used in this step, for example, WG280 manufactured by SCHOTT can be mentioned as one used to prevent the reaction of the photosensitive compound for forming an optical functional layer.
Moreover, as what is used in order to prevent that the crosslink formation reaction of the said crosslinkable liquid crystal material advances, for example, when using the photosensitive compound for optical function layer formation whose maximum absorption wavelength is 270 nm-310 nm In addition, a UV cut filter (manufactured by Asahi Spectroscopic Co., Ltd .: SU0325) that shields ultraviolet rays of 325 nm to 400 nm can be mentioned.

3. Next, the liquid crystal alignment process used in the present invention will be described. This step is a step of aligning the crosslinkable liquid crystal material contained in the optical functional layer forming layer according to the orientation imparted to the optical functional layer forming layer by the orientation imparting step.

  In this step, the method for aligning the crosslinkable liquid crystal material is not particularly limited as long as it is a method capable of aligning the crosslinkable liquid crystal material according to the orientation according to the type of the crosslinkable liquid crystal material. . As such a method, usually, the optical functional layer forming layer is heated to a temperature not lower than the crystal-liquid crystal phase transition temperature of the crosslinkable liquid crystal material and lower than the liquid crystal-isotropic phase transition temperature. Are preferably used.

  As described above, this step is a step of aligning the crosslinkable liquid crystal material by heating the phase difference layer forming layer. As a heating method used in this step, the orientation imparting is performed. A method in which the retardation layer forming layer can be heated so that the surface irradiated with polarized ultraviolet rays in the process reaches the crystal-liquid crystal phase transition temperature of the crosslinkable liquid crystal material before the opposite surface. Is preferred. As such a heating method, heating is performed from both sides of the retardation layer forming layer, and the heating temperature for the surface irradiated with the polarized ultraviolet light is set higher than the heating temperature for the opposite surface. And a method of heating the retardation layer forming layer only from the side irradiated with the polarized ultraviolet light. In this step, any of these heating methods can be preferably used, but the latter heating method is particularly preferable. By using the method of heating the phase difference layer forming layer only from the side irradiated with the polarized ultraviolet light, the surface irradiated with the polarized ultraviolet light is the surface irradiated with the polarized ultraviolet light. This is because it is easy to heat the retardation layer forming layer so as to reach the crystal-liquid crystal phase transition temperature of the crosslinkable liquid crystal material before the surface on the opposite side. In the case of a method in which the phase difference layer forming layer is heated only from the side irradiated with the polarized ultraviolet light, the surface on the opposite side of the surface irradiated with the polarized ultraviolet light is cooled to cool the temperature of the opposite surface. The rise may be suppressed.

4). Next, the liquid crystal crosslinking step used in the present invention will be described. This step is a step of crosslinking the crosslinkable liquid crystal material arranged in the liquid crystal alignment step.

  In this step, the method for crosslinking the crosslinkable liquid crystal material is not particularly limited as long as it is a method capable of causing a crosslinking formation reaction of the crosslinkable functional group of the crosslinkable liquid crystal material. A method corresponding to the type of the crosslinkable functional group possessed by the crosslinkable liquid crystal material can be appropriately selected and used. As such a method, for example, when a crosslinkable liquid crystal material having an ultraviolet polymerizable functional group is used, an ultraviolet ray having a wavelength capable of causing a polymerization reaction of the ultraviolet polymerizable functional group is used. The method for irradiating the optical functional layer forming layer is used. When such a method of irradiating ultraviolet rays is used, non-polarized ultraviolet rays are usually used from the viewpoint that the ultraviolet rays for reacting the crosslinkable liquid crystal material have high reactivity.

  Next, the present invention will be described more specifically by showing examples.

(Synthesis example)
1. Synthesis of Photosensitive Compound I for Optical Function Layer Formation 1.0 g of acrylic resin modifying silicone (X-24-8201) manufactured by Shin-Etsu Chemical Co., Ltd. as a lyophobic monomer, methyl (4) as a photoreactive monomer -(2-Methacryloyloxyethoxy))-cinnamate (3.0 g) and 2,2'-azobisisobutyronitrile (0.016 g) were dissolved in dehydrated tetrahydrofuran (28 g). Next, it heated at 65 degreeC under nitrogen atmosphere for 23 hours. Furthermore, the obtained reaction solution was dropped into 800 ml of methanol, the precipitate was filtered, and dried under reduced pressure. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. By such a method, 3.3 g of photosensitive compound I for forming an optical functional layer having a weight average molecular weight of 120,000 (GPC: solvent 10 mM, lithium bromide-NMP solution, polystyrene conversion) was obtained. Here, the copolymerization ratio (molar ratio) of the photosensitive compound I for forming an optical functional layer calculated from ¹ H-NMR measurement was photoreactive monomer: lyophobic monomer = 36: 1.

2. Synthesis of Photosensitive Compound II for Optical Function Layer Formation Kyoeisha Chemical Co., Ltd. Light Ester FM-108 as a lyophobic monomer, 2.0 g, methyl as a photoreactive monomer (4- (2-methacryloyloxyethoxy)) -6.0 g of cinnamate and 0.032 g of 2,2'-azobisisobutyronitrile were dissolved in 28 g of dehydrated tetrahydrofuran. Then, it heated at 65 degreeC for 20 hours in nitrogen atmosphere. Furthermore, the obtained reaction solution was added dropwise to 1000 ml of methanol, and the precipitate was filtered, washed with methanol, and dried under reduced pressure at room temperature. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. By such a method, 6.5 g of photosensitive compound II for forming an optical functional layer having a weight average molecular weight of 270000 (GPC: solvent THF, polystyrene conversion) was obtained.

3. Synthesis of photosensitive compound III for forming optical functional layer 0.5 g of acrylic resin modifying silicone (X-24-8201) manufactured by Shin-Etsu Chemical Co., Ltd. as a lyophobic monomer and 1- as a photoreactive monomer [6- [4- [2-methoxy-4-[(E) -2-methoxycarbonylvinyl] phenoxycarbonyl] phenoxy] hexyloxycarbonyl] -1-methylethylene 2.3 g, 2,2′-azobisiso 0.008 g of butyronitrile was dissolved in 16 g of dehydrated tetrahydrofuran. Next, it was heated at 65 ° C. for 24 hours under a nitrogen atmosphere. Furthermore, the obtained reaction solution was dripped at 1000 ml of methanol, the deposit was filtered, and it dried under reduced pressure. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. By such a method, 2.3 g of photosensitive compound III for forming an optical functional layer having a weight average molecular weight of 120,000 (GPC: THF solution, polystyrene conversion) was obtained. Here, the copolymerization ratio (molar ratio) of the photosensitive compound III for forming an optical functional layer calculated from ¹ H-NMR measurement was photoreactive monomer: lyophobic monomer = 40: 1.

4). Synthesis of Photosensitive Compound IV for Optical Function Layer Formation 0.8 g of acrylic resin modifying silicone (X-24-8201) manufactured by Shin-Etsu Chemical Co., Ltd. as a lyophobic monomer and 1- as a photoreactive monomer [6- [4- [2-methoxy-4-[(E) -2-methoxycarbonylvinyl] phenoxycarbonyl] phenoxy] hexyloxycarbonyl] -1-methylethylene 2.0 g, 2,2′-azobisiso 0.007 g of butyronitrile was dissolved in 18 g of dehydrated tetrahydrofuran. Next, it was heated at 65 ° C. for 24 hours under a nitrogen atmosphere. Furthermore, the obtained reaction solution was dripped at 1000 ml of methanol, the deposit was filtered, and it dried under reduced pressure. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. By such a method, 2.3 g of photosensitive compound IV for forming an optical functional layer having a weight average molecular weight of 120,000 (GPC: THF solution, polystyrene conversion) was obtained. Here, the copolymerization ratio (molar ratio) of the photosensitive compound IV for forming an optical functional layer calculated from 1H-NMR measurement was photoreactive monomer: lyophobic monomer = 20: 1.

5. Synthesis of photosensitive compound V for optical functional layer formation 0.21 g of acrylic resin modifying silicone (X-24-8201) manufactured by Shin-Etsu Chemical Co., Ltd. as a lyophobic monomer and 1- as a photoreactive monomer [6- [4- [2-methoxy-4-[(E) -2-methoxycarbonylvinyl] phenoxycarbonyl] phenoxy] hexyloxycarbonyl] -1-methylethylene 1.5 g, 2,2′-azobisiso 0.005 g of butyronitrile was dissolved in 10 g of dehydrated tetrahydrofuran. Next, it was heated at 65 ° C. for 24 hours under a nitrogen atmosphere. Furthermore, the obtained reaction solution was dripped at 1000 ml of methanol, the deposit was filtered, and it dried under reduced pressure. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. By such a method, 1.5 g of photosensitive compound V for forming an optical functional layer having a weight average molecular weight of 135000 (GPC: THF solution, polystyrene conversion) was obtained. Here, the copolymerization ratio (molar ratio) of the photosensitive compound V for forming an optical functional layer calculated from ¹ H-NMR measurement was photoreactive monomer: lyophobic monomer = 60: 1.

6). Synthesis of photosensitive compound (poly [methyl (4- (2-methacryloyloxyethoxy))-cinnamate])

  Methyl (4- (2-methacryloyloxyethoxy))-cinnamate 6.0 g and 2,2′-azobisisobutyronitrile 0.016 g were dissolved in dehydrated tetrahydrofuran 14 g. Next, it heated at 65 degreeC for 20 hours in nitrogen atmosphere. Furthermore, the obtained reaction solution was added dropwise to 1000 ml of methanol, and the precipitate was filtered, washed with methanol, and dried under reduced pressure at room temperature. The obtained solid was dissolved in 5 parts by mass of chloroform, the solution was added dropwise to 1 L of hexane, the precipitate was filtered, and then dried under reduced pressure. As a result, 6.0 g of a photosensitive compound having a weight average molecular weight of 41000 (GPC: solvent THF, converted to polystyrene) was obtained.

<Example 1>
(Production of shielding layer)
Pentaerythritol triacrylate (PET-30, Nippon Kayaku) 40 parts by mass, photopolymerization initiator 1-hydroxy-cyclohexyl-phenylketone (trade name IRGACURE184, manufactured by Ciba Specialty Chemicals) 2 parts by mass, methyl ethyl ketone 29 parts by mass A solution consisting of 58 parts by mass of toluene is bar-coated on a triacetylcellulose film (FT-T80UZ, manufactured by Fuji Photo Film Co., Ltd.), dried at 80 ° C. for 3 minutes, and then irradiated with a UV irradiation device (Fusion UV Systems Japan Co., Ltd.). A light-shielding layer having a thickness of 1 μm was produced by irradiating with an ultraviolet ray of 70 mJ / cm ² under a nitrogen atmosphere using a light source (manufactured, light source: H bulb).

(Preparation of optical functional layer forming composition)
0.1 parts by mass of photosensitive compound I for forming an optical functional layer, 99.9 parts by mass of a crosslinkable liquid crystal material represented by the following formula, photopolymerization initiator: 1-hydroxy-cyclohexyl-phenyl ketone (trade name: IRGACURE 184, Ciba (Specialty Chemicals) 0.04 parts by mass were dissolved in methyl ethyl ketone to prepare a composition for forming an optical functional layer as a 10% solid content solution.

  Here, a and b in the above formula are integers of 2 to 5, respectively.

(Formation of optical functional layer)
The composition for forming an optical functional layer was coated on the shielding layer with a wire bar and dried by heating at 100 ° C. for 3 minutes. Next, a shot WG280 and Asahi Spectroscopic SU0325 were placed as a cut filter in an ultraviolet irradiation device using a 500 W Deep UV lamp to limit the wavelength, and further, the wire grid polarizing plate was transmitted to obtain polarized ultraviolet rays. Next, with respect to the film | membrane with which the said composition for optical function layer formation was apply | coated, polarized ultraviolet rays were irradiated in 40 mJ / cm < ² > air | atmosphere from the orthogonal | vertical direction with respect to the film | membrane. Here, the intensity of polarized ultraviolet rays was measured with a UV RADIO METER UVR-400A (manufactured by ASONE Corporation) using a sensor S-310 (measurement range: 280 nm to 360 nm). Next, after irradiation with polarized ultraviolet light, the crosslinkable liquid crystal material is aligned by heating for 3 minutes in an oven set at 70 ° C. so that warm air is applied from the surface irradiated with polarized ultraviolet light, The coating film was cured by irradiation with 120 mJ / cm ² non-polarized ultraviolet light in an atmosphere. Thereby, the aligned liquid crystal was fixed, and an optical functional film was manufactured. At this time, the film thickness of the optical functional layer was 0.8 μm.
Also included in the lyophobic group in the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by photoelectron X-ray analysis (XPS apparatus ESCA-3400 type: manufactured by KRATOS ANALYTICAL, UK) The silicon ratio is 180 times the theoretical silicon ratio calculated from the composition ratio of the solid content in the composition for forming an optical functional layer, and the reaction product of the photosensitive compound I for forming an optical functional layer is It was confirmed that the optical functional layer was unevenly distributed on the surface opposite to the transparent substrate.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring device (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd.). there were.

<Example 2>
An optical functional film was prepared in the same manner as in Example 1 except that the optical functional layer-forming photosensitive compound II was used in place of the optical functional layer-forming photosensitive compound I to prepare the optical functional layer-forming composition. Produced. At this time, the film thickness of the optical functional layer was 0.8 μm.
Also included in the lyophobic group out of the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by photoelectron X-ray analysis (XPS apparatus ESCA-3400 type: manufactured by KRATOS ANALYTICAL, UK) The fluorine ratio is 360 times the theoretical fluorine ratio calculated from the composition ratio of the solid content in the optical functional layer forming composition, and the reaction product of the photosensitive compound II for optical functional layer formation is It was confirmed that the optical functional layer was unevenly distributed on the surface opposite to the transparent substrate.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring apparatus (automatic birefringence meter KOBRA-WR, manufactured by Oji Scientific Instruments Co., Ltd.). there were.

<Comparative Example 1>
An optical functional film was produced in the same manner as in Example 1 except that the photosensitive compound I was used instead of the photosensitive compound I for forming an optical functional layer. At this time, the film thickness of the optical functional layer was 0.8 μm.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring device (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd.). there were.

<Example 3>
0.05 mass parts of photosensitive compound I for forming an optical functional layer, 99.95 mass parts of a crosslinkable liquid crystal material represented by the following formula, photopolymerization initiator: 1-hydroxy-cyclohexyl-phenyl ketone (trade name IRGACURE184, Ciba (Specialty Chemicals) 0.04 parts by mass were dissolved in methyl ethyl ketone to prepare a composition for forming an optical functional layer as a 10% solid content solution. The composition for forming an optical functional layer was applied onto the shielding layer with a wire bar and dried by heating at 30 ° C. for 3 minutes. Next, a shot WG280 and Asahi Spectroscopic SU0325 were placed as a cut filter in an ultraviolet irradiation device using a 500 W Deep UV lamp to limit the wavelength, and further, the wire grid polarizing plate was transmitted to obtain polarized ultraviolet rays.

ここで、上記式におけるａ、ｂはそれぞれ２〜５の整数である。

Here, a and b in the above formula are integers of 2 to 5, respectively.

Next, with respect to the film | membrane with which the said composition for optical function layer formation was apply | coated, polarized ultraviolet rays were irradiated in 8 mJ / cm < ² > air | atmosphere from the orthogonal | vertical direction with respect to the film | membrane. Here, the intensity of polarized ultraviolet rays was measured with a UV RADIO METER UVR-400A (manufactured by ASONE Corporation) using a sensor S-310 (measurement range: 280 nm to 360 nm). Next, after irradiation with polarized ultraviolet light, the crosslinkable liquid crystal material is aligned by heating for 3 minutes in an oven set at 100 ° C. so that warm air is applied from the side irradiated with polarized ultraviolet light, The coating film was cured by irradiation with 120 mJ / cm ² non-polarized ultraviolet light in an atmosphere. Thereby, the arranged liquid crystal was fixed, and an optical functional film was manufactured. At this time, the film thickness of the optical functional layer was 0.8 μm.
Also included in the lyophobic group in the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by photoelectron X-ray analysis (XPS apparatus ESCA-3400 type: manufactured by KRATOS ANALYTICAL, UK) The silicon ratio is 150 times the theoretical silicon ratio calculated from the composition ratio of the solid content in the composition for forming an optical functional layer, and the reaction product of the photosensitive compound I for forming an optical functional layer is It was confirmed that the optical functional layer was unevenly distributed on the surface opposite to the transparent substrate.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring apparatus (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments) at 41 nm. there were.

<Example 4>
An optical functional film was produced in the same manner as in Example 3, except that the photosensitive compound III for forming an optical functional layer was used instead of the photosensitive compound I for forming an optical functional layer. At this time, the film thickness of the optical functional layer was 0.8 μm.
Also included in the lyophobic group in the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by photoelectron X-ray analysis (XPS apparatus ESCA-3400 type: manufactured by KRATOS ANALYTICAL, UK) Is 150 times the theoretical silicon ratio calculated from the composition ratio of the solid content in the composition for forming an optical functional layer, and the reaction product of the photosensitive compound III for forming an optical functional layer is It was confirmed that the optical functional layer was unevenly distributed on the surface opposite to the transparent substrate.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measurement apparatus (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments) at 114 nm. there were.

<Example 5>
An optical functional film was produced in the same manner as in Example 3, except that the optical functional layer forming composition photosensitive compound IV was used in place of the optical functional layer forming composition photosensitive compound I. At this time, the film thickness of the optical functional layer was 0.8 μm.
Photoelectron X-ray analysis (XPS equipment ESCA-3400 type: KRATOS, UK)
The ratio of silicon contained in the lyophobic group in the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by ANALYTICAL) is the solid content in the optical functional layer forming composition. It is 150 times the theoretical silicon ratio calculated from the composition ratio of the minute, and the reaction product of the photosensitive compound IV for forming the optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate. I confirmed.

(Evaluation)
The optical functional film thus obtained was measured for in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring device (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments) at 109 nm. there were.

<Example 6>
An optical functional film was produced in the same manner as in Example 3, except that the optical functional layer forming composition photosensitive compound V was used instead of the optical functional layer forming composition photosensitive compound I. At this time, the film thickness of the optical functional layer was 0.8 μm.
Also included in the lyophobic group in the atomic composition ratio of the surface opposite to the transparent substrate of the optical functional layer obtained by photoelectron X-ray analysis (XPS apparatus ESCA-3400 type: manufactured by KRATOS ANALYTICAL, UK) The silicon ratio is 150 times the theoretical silicon ratio calculated from the composition ratio of the solid content in the composition for forming an optical functional layer, and the reaction product of the photosensitive compound V for forming an optical functional layer is It was confirmed that the optical functional layer was unevenly distributed on the surface opposite to the transparent substrate.

(Evaluation)
The optical functional film thus obtained was measured for an in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring apparatus (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments) at 46 nm. there were.

<Comparative example 2>
An optical functional film was produced in the same manner as in Example 3 except that the photosensitive compound was used in place of the photosensitive compound I for forming an optical functional layer. At this time, the film thickness of the optical functional layer was 0.8 μm.

(Evaluation)
The optical functional film thus obtained was measured for in-plane retardation (Re) at a wavelength of 590 nm using an automatic birefringence measuring device (automatic birefringence meter KOBRA-WR manufactured by Oji Scientific Instruments). there were.

It is the schematic which shows an example of the method of forming an optical function layer using the photosensitive compound for optical function layer formation of this invention. It is the schematic which shows an example of the optical function film of this invention. It is the schematic which shows an example of the manufacturing method of the optical function film of this invention. It is the schematic which shows a part of common liquid crystal display device typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Optical functional layer 2 '... Optical functional layer formation layer 10 ... Optical functional film 100 ... Liquid crystal display device 101 ... Liquid crystal cell 102A, 102B ... Polarizing plate A ... Photosensitive compound for optical functional layer formation

Claims (11)

  A photosensitive compound for forming an optical functional layer, comprising a photoreactive group exhibiting photoreactivity and a lyophobic group exhibiting lyophobicity.   The photosensitive compound for forming an optical functional layer according to claim 1, wherein the lyophobic group contains silicon or fluorine.   3. The photosensitive compound for forming an optical functional layer according to claim 1, wherein the lyophobic group is a dimethylsiloxane chain or a fluoroalkyl chain.   The photosensitive compound for forming an optical functional layer according to any one of claims 1 to 3, wherein the photoreactive group has a mesogenic structure.   The claim according to any one of claims 1 to 4, wherein the photoreactive monomer having the photoreactive group and the lyophobic monomer having the lyophobic group are copolymerized. The photosensitive compound for forming an optical functional layer described in the item.   An optical functional layer forming comprising the photosensitive compound for forming an optical functional layer according to any one of claims 1 to 5 and a crosslinkable liquid crystal material having a crosslinkable functional group. Composition.   The composition for forming an optical functional layer according to claim 6, comprising a solvent.   The composition for forming an optical functional layer according to claim 6 or 7, wherein the content of the photosensitive compound for forming an optical functional layer is 1% by mass or less based on the total solid content. Crosslinking formed on a transparent substrate, the photosensitive compound for forming an optical functional layer according to any one of claims 1 to 5, and a crosslinkable functional group formed on the transparent substrate. An optical functional film having an optical functional layer containing a crosslinked product of a functional liquid crystal material,
A reaction product of the photosensitive compound for forming an optical functional layer is unevenly distributed on the surface of the optical functional layer opposite to the transparent substrate.   The optical functional film according to claim 9, wherein a content of the reaction product of the photosensitive compound for forming an optical functional layer in the optical functional layer is 1% by mass or less. An optical functional layer forming layer is formed on the transparent substrate by applying the optical functional layer forming composition according to any one of claims 6 to 8 using a transparent substrate. A layer forming step for forming an optical functional layer;
An orientation imparting step for imparting orientation to the crosslinkable liquid crystal material to the optical functional layer forming layer by irradiating the optical functional layer forming layer with polarized ultraviolet rays and reacting the photoreactive group;
A liquid crystal alignment step of aligning the crosslinkable liquid crystal material;
And a liquid crystal crosslinking step of crosslinking the crosslinkable liquid crystal material.

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