Composition for forming retardation film and method for producing single-layer retardation material

Abstract

This composition for forming a retardation film contains a polymer (P) having a terminal group derived from a polymerization control agent (A) containing a structure selected from the group consisting of trithiocarbonate, dithiocarbamate, dithiobenzoate, and dithiocarbonate. The polymer (P) has a structural unit (X) derived from a monomeric compound having a photosensitive group (p) and a polymerizable unsaturated bond group.

Description

Composition for forming a phase difference film and method for manufacturing a single-layer phase difference material

[0001] The present invention relates to a phase difference film forming composition and a phase difference material containing a specific polymer component. More specifically, the present invention relates to a phase difference film forming composition that can be suitably used for materials having optical properties suitable for applications such as display devices and recording materials (particularly optical compensation films such as polarizers and phase difference plates for liquid crystal displays and organic EL (Electroluminescence) display devices), and a single-layer phase difference material obtained from the above-mentioned phase difference film forming composition.

[0002] Due to demands for improved display quality and weight reduction in liquid crystal display devices, there is a growing need for polymer films with controlled internal molecular orientation structures as optical compensation films such as polarizers and phase difference plates. These polymer films are known as films that alter the polarization state of light and impart birefringence (also called birefringent films or phase difference films). In the following, materials that alter the polarization state of light will also be referred to as phase difference materials. To meet these demands, birefringent films utilizing the optical anisotropy of polymerizable liquid crystal compounds are being developed. The polymerizable liquid crystal compounds used here are generally liquid crystal compounds having polymerizable groups and liquid crystal structural parts (structural parts having spacer parts and mesogenic parts), and (meth)acrylic groups are widely used as these polymerizable groups.

[0003] Polymerizable liquid crystal compounds can exhibit optical anisotropy by, for example, contacting them with an alignment-treated substrate and irradiating them with radiation such as ultraviolet light. Prior art includes a method (Patent Document 1) in which a specific polymerizable liquid crystal compound having (meth)acrylic groups is supported between support structures formed on a polymer film having alignment ability (hereinafter also referred to as an alignment film), and the compound is irradiated with radiation while being kept in a liquid crystal state. Another known method (Patent Document 2) involves adding a photopolymerization initiator to a mixture of two polymerizable liquid crystal compounds having (meth)acrylic groups, or a composition of this mixture mixed with chiral liquid crystal, and then irradiating it with ultraviolet light on an alignment-treated substrate.

[0004] In optical compensation for liquid crystal displays and organic EL displays, it is known that the Nz coefficient, a parameter representing the characteristics of the phase difference material, is preferably 0.5 or close to it (Patent Document 3). Here, the Nz coefficient is given by the formula {Nz = (nx - nz) / (nx - ny)}, where nx is the refractive index of the slow axis in the plane of the phase difference material, ny is the refractive index of the fast axis, and nz is the refractive index in the thickness direction of the phase difference material.

[0005] Generally, to control the Nz coefficient to around 0.5, multiple positive A plates (nx > ny = nz), positive C plates (nx = ny > nz), and negative C plates (nz > nx = ny) are combined to achieve the desired optical properties. On the other hand, there is also active development of birefringent films (hereinafter referred to as single-layer phase difference films) that exhibit the desired optical properties with only a single layer of resin. Single-layer phase difference films allow for a reduction in the number of films, thus enabling thinner and lighter birefringent films. Furthermore, the film manufacturing process can be simplified, leading to reduced manufacturing costs and improved yield.

[0006] As an example of the development of the aforementioned single-layer phase difference film, birefringent films using polymerizable liquid crystal compounds or their polymers without using an alignment film have been reported (Patent Documents 4 and 5).

[0007] Furthermore, various single-layer phase difference films have been reported, such as birefringent films (Patent Documents 6 and 7) that utilize the axially selective photoreaction and resulting photo-orientation of photoresponsive polymer liquid crystals (liquid crystalline polymethacrylate with photoresponsive mesogens in its side chains).

[0008] Japanese Patent Publication No. Sho 62-70407, Japanese Patent Publication No. Hei 9-208957, International Publication No. 2018 / 221276, Japanese Patent Publication No. 2002-517605, International Publication No. 2008 / 031243, Japanese Patent Publication No. 2008-164925, Japanese Patent Publication No. Hei 11-189665

[0009] The present inventors have proposed a single-layer phase difference material using a photoresponsive polymer liquid crystal (International Publication No. 2023 / 171757, International Publication No. 2024 / 071364, International Publication No. 2024 / 038887). However, the aforementioned single-layer phase difference material has challenges in manufacturing reproducibility and optical property reproducibility due to its multi-component system consisting of three or more components, the use of two or more polymerizable functional groups, and its synthesis by free radical polymerization without the use of control agents. Furthermore, due to the lack of control over the polymer structure (molecular weight dispersion and terminal functional groups), there are challenges in optical properties, coatability, and phase difference stability under high temperature and high humidity conditions. Therefore, even if good properties are obtained with the aforementioned single-layer phase difference material, reproducibility cannot be achieved in the actual manufacturing process, leading to problems such as poor yield.

[0010] If these technical challenges can be resolved, it would result in significant cost advantages for panel manufacturers and could also lead to significant improvements in image quality.

[0011] The present invention was made to solve the above-mentioned problems, and aims to provide a single-layer phase difference film that, by using highly controlled living radical polymerization, has better manufacturing reproducibility and optical property reproducibility compared to conventional methods, can simultaneously achieve a large phase difference equivalent to 200-300 nm and a low haze value of 0.2 or less, and in addition has good coatability and processability, and exhibits little phase difference fluctuation under high temperature and high humidity conditions.

[0012] The inventors of the present invention conducted diligent research to solve the above problems and, as a result, found that they could solve the above problems, and completed the present invention having the following gist.

[0013] That is, the present invention includes the following. [1] A composition for forming a retardation film, containing a polymer (P) having a terminal group derived from a polymerization controller (A) containing a structure selected from the group consisting of trithiocarbonate, dithiocarbamate, dithiobenzoate, and dithiocarbonate, wherein the polymer (P) is a polymer having a structural unit (X) derived from a monomer compound having a photosensitive group (p) and a polymerizable unsaturated bond group. [2] The composition for forming a retardation film according to [1], wherein the polymerization controller (A) is represented by a formula selected from the group consisting of the following formulas (a) to (e). (In the formulas (a) to (e), R １ represents any one of the following formulas (f-1) to (f-3). R ２ represents the following formula (g-1) or (g-2). R ３ each independently represents any one of the following formulas (h-1) to (h-6). R ４ represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms.) (In the formulas (f-1) to (f-3), R ５ and R ７ each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and R ６ represents a single bond or an alkylene group having 1 to 6 carbon atoms. * represents a bonding site.) (In the formulas (g-1) to (g-2), R ８ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, a carboxy group, or a carboxylic acid ester group, R ９ and R １０ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a phenyl group, R １１ represents a single bond or an alkylene group having 1 to 6 carbon atoms, R １２ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. * represents a bonding site.) (In the formulas (h-1) to (h-6), R １３ represents a single bond or an alkylene group having 1 to 6 carbon atoms, R １４ represents a single bond or an alkylene group having 1 to 6 carbon atoms, R １５R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １６ represents a carboxyl group or a hydroxyl group. * represents a bonding site.) [3] The phase difference film forming composition according to [1] or [2], wherein the polymerization control agent (A) is a compound represented by any of the following formulas (R-1) to (R-24). (In formula (R-10), Me represents a methyl group.) [4] A method for producing a single-layer phase difference material comprising the following steps (I) to (III): (I): A step of applying the phase difference film forming composition described in any of [1] to [3] onto a substrate to form a coating film (II): A step of irradiating the coating film with polarized ultraviolet light (III): A step of heating the coating film irradiated with ultraviolet light to obtain a single-layer phase difference material [5] A single-layer phase difference material formed from the phase difference film forming composition described in any of [1] to [3].

[0014] The present invention provides a single-layer phase difference film that offers improved manufacturing reproducibility and optical property reproducibility compared to conventional methods, simultaneously achieving a large phase difference equivalent to 200-300 nm and a low haze value of 0.2 or less, as well as good coatability and processability, and minimal phase difference fluctuations under high temperature and high humidity conditions.

[0015] [Composition for forming a phase difference film] The phase difference film forming composition of the present invention contains a polymer (P).

[0016] [Polymer (P)] Polymer (P) has terminal groups derived from a polymerization control agent (A) containing a structure selected from the group consisting of trithiocarbonate, dithiocarbamate, dithiobenzoate, and dithiocarbonate. Polymer (P) is a polymer having structural units (X) derived from monomer compounds having a photosensitive group (p) and a polymerizable unsaturated bonding group. Polymer (P) has, for example, a photosensitive group (p) in its side chain. Therefore, for example, polymer (p) has a photosensitive group (p) as a side chain p. Polymer (P) is a polymer different from polymers selected from the group consisting of polyimide precursors and polyimides.

[0017] As the polymerization control agent (A), a compound represented by a formula selected from the group consisting of the following formulas (a) to (e) is preferred. (In formulas (a) to (e), R １ R represents one of the following equations (f-1) to (f-3). ２ R represents the following formula (g-1) or (g-2). ３ Each of these independently represents one of the following equations (h-1) to (h-6). ４ (This represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms.) (In formulas (f-1) to (f-3), R ５ and R ７ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, R ６ (* represents a single bond or an alkylene group with 1 to 6 carbon atoms. * represents a bonding site.) (In formulas (g-1) to (g-2), R ８ R represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, a carboxyl group, or a carboxylic acid ester group. ９ and R １０ Each of these independently represents a hydrogen atom, a C1-C6 alkyl group, a C1-C6 alkoxy group, or a phenyl group, and R １１ R represents a single bond or an alkylene group having 1 to 6 carbon atoms. １２ (* represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. * represents a bonding site.) (In formulas (h-1) to (h-6), R １３ R represents a single bond or an alkylene group having 1 to 6 carbon atoms. １４ R represents a single bond or an alkylene group having 1 to 6 carbon atoms. １５ R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １６ (* represents a carboxyl group or hydroxyl group. * represents a bonding site.)

[0018] R in the above formula ４ ~R １６ In this, the alkyl group, alkoxy group, and alkylene group may be branched.

[0019] Specific examples of polymerization control agents (A) include any of the compounds represented by the following formulas (R-1) to (R-24). (In formula (R-10), Me represents a methyl group.)

[0020] During the radical polymerization process, the polymerization control agent (A) remains in the polymer with a moiety containing -C(=S)-S- bonded to the end portion of the polymer.

[0021] The polymer (P) is preferably a photosensitive side-chain polymer capable of exhibiting liquid crystalline properties (hereinafter simply referred to as a side-chain polymer or side-chain polymer liquid crystal). In this case, the coating film obtained using the phase difference film forming composition is a film having a photosensitive side-chain polymer capable of exhibiting liquid crystalline properties. This coating film is subjected to orientation treatment by polarized irradiation and subsequent firing without rubbing treatment. After polarized irradiation, the side-chain polymer film is heated to obtain a film with optical anisotropy (hereinafter also referred to as a single-layer phase difference material). At this time, the slight axially selective anisotropy exhibited by polarized irradiation acts as a driving force, and the liquid crystalline side-chain polymer itself efficiently reorients through self-assembly. As a result, highly efficient orientation treatment is achieved as a single-layer phase difference material, and a single-layer phase difference material with high optical anisotropy can be obtained.

[0022] In the present invention, photosensitivity refers to the property of undergoing any of the following reactions: (A-1) photocrosslinking (photodimerization), (A-2) photoisomerization, or (A-3) photofleece rearrangement; or a combination of these reactions. The polymer (P) preferably has side chains that undergo (A-1) photocrosslinking or (A-2) photoisomerization.

[0023] Examples of photosensitive groups (p) include the group represented by the following formula (p1). (In formula (p1), n1 and n2 are independently 0, 1, 2, or 3. L is a single bond or an alkylene group having 1 to 30 carbon atoms, and one or more hydrogen atoms of the alkylene group may be substituted with a fluorine atom or a monovalent organic group. Also, -CH in L ２ -, -O-, -S-, -NR Ｌ -, -C(=O)-, -C(=O)-O-, -O-C(=O)-, -C(=O)-NR Ｌ -, -NR Ｌ -C(=O)-, -NR Ｌ -C(=O)-NR Ｌ-, -CH=CH-, alicyclic groups and aromatic groups (where R Ｌ Each of these independently represents a hydrogen atom or a monovalent organic group. They may be replaced by a group selected from the group consisting of ( ). A １ These are, independently, single bonds, -O-, -S-, and -CH. ２ -, -C(=O)-O-, -O-C(=O)-, -C(=O)-NH-, or -NH-C(=O)-. Q １ This is a divalent group, which is an aromatic group, a polycyclic aromatic group, an alicyclic group, a phenylenecyclohexylene group, a heterocyclic group, or a fused cyclic group. Q １ When the number of Q is 2 or more, １ They may be the same or different from each other. Q ２ This is a single bond, a phenylene group, or a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms. Q ２ When the number of Q is 2 or more, ２ They may be the same or different from each other. １ and X ２ Each of these is independently a single bond, -CH ２ -, -O-, -S-, -C(=O)-, -N=N-, -CH=CH-, -C≡C-, -NR Ｘ -, -C(=O)-O-, -OC(=O)-, -CH=CH-C(=O)-O-, -OC(=O)-CH=CH-, -C(=O)-NR Ｘ -, -NR Ｘ -C (=O)- or -NR Ｘ -C(=O)-NR Ｘ - (However, R Ｘ Each of these independently represents a hydrogen atom or a monovalent organic group. １ When the number of X is 2 or more, １ X may be the same or different from each other. ２ When the number of X is 2 or more, ２These may be the same or different from each other. R is a hydrogen atom, a cyano group, a halogen atom, a carboxyl group, a hydroxyl group, a C1-C5 alkyl group, a C2-C6 alkylcarbonyl group, a C3-C7 cycloalkyl group, a C1-C5 alkoxy group, or a C2-C7 aliphatic ester group. Align is a divalent group having a photoreactive site. The hydrogen atom in the ring structure in formula (p1) may be substituted with substituents selected from a C1-C6 alkyl group, a C2-C6 alkylcarbonyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group, a C1-C6 haloalkoxy group, a halogen atom, a cyano group, and a nitro group. The dashed line is a bond. However, L is A １ At the end of the side, -Q １ -X １ - * (* is A) １ It does not have a structure represented by (representing a bonding relationship with).

[0024] Q ２ If the group is a phenylene group, some or all of the hydrogen atoms of the phenylene group may be substituted with a cyano group, a halogen atom, a C1-C5 alkyl group, a C2-C6 alkylcarbonyl group, or a C1-C5 alkoxy group.

[0025] Examples of aliphatic ester groups having 2 to 7 carbon atoms include R ａ -O-C(=O)- group (R ａ This represents an alkyl group having 1 to 6 carbon atoms.

[0026] The side-chain polymer is, for example, (i) a thermotropic polymer liquid crystal that exhibits liquid crystalline properties in a predetermined temperature range and is a polymer having photoreactive side chains. The side-chain polymer is (ii) a polymer liquid crystal that reacts to ultraviolet light in the wavelength range of 200 to 400 nm, preferably 240 to 400 nm, and exhibits liquid crystalline properties in the temperature range of 80 to 300°C. The side-chain polymer is (iii) preferably has photoreactive side chains that react to ultraviolet light in the wavelength range of 200 to 400 nm, preferably 240 to 400 nm, particularly polarized ultraviolet light, and exhibit axially selective optical anisotropy. When the substrate used is plastic, from the viewpoint of the heat resistance of the substrate, the side-chain polymer is (vi) preferably exhibits liquid crystalline properties in the temperature range of 80 to 300°C, and more preferably exhibits liquid crystalline properties in the temperature range of 80 to 150°C.

[0027] As described above, the side-chain polymer has photoreactive side chains. The structure of the side chains is not particularly limited, but it is preferable to have a structure that produces the reactions shown in (A-1), (A-2), and / or (A-3), and in particular, a structure that produces (A-1) a photocrosslinking reaction and / or (A-2) a photoisomerization reaction. The structure that produces (A-1) a photocrosslinking reaction is preferable because the structure after the reaction can stably maintain the orientation of the side-chain polymer for a long period of time even when exposed to external stress such as heat. The structure that produces (A-2) a photoisomerization reaction is preferable because it enables orientation treatment with a lower exposure compared to photocrosslinking and photofleece transition, thereby increasing production efficiency during the manufacture of phase difference films.

[0028] The group represented by formula (p1) (hereinafter also referred to as group p1) is preferably one of the following formulas (p1-1) to (p1-6). Furthermore, from the viewpoint of solubility in the solvent, it is preferable that a single group p1 has three or fewer benzene rings.

[0029] (In formulas (p1-1) to (p1-6), n1, n2, L, A １ Q １ Q ２ , X １ , X ２ , and R are n1, n2, L, and A in equation (p1), respectively. １ Q１ and Q ２ and X １ and X ２ are synonymous with R. P １ is a single bond, a phenylene group or a divalent alicyclic hydrocarbon group having 5 to 8 carbon atoms. Z ａ and Z ｂ are each independently a hydrogen atom, a halogen atom, a cyano group, a phenyl group or an alkyl group having 1 to 3 carbon atoms, and part or all of the hydrogen atoms of this alkyl group may be substituted with fluorine atoms. T １ is a single bond or an alkylene group having 1 to 12 carbon atoms, and part or all of the hydrogen atoms of the alkylene group may be substituted with halogen atoms. A ２ and D １ are each independently a single bond, -O-, -S-, -CH ２ -, -C(=O)-O-, -O-C(=O)-, -C(=O)-NH- or -NH-C(=O)-. However, when T １ is a single bond, A ２ is also a single bond. Y １ and Y ２ are a phenylene group or a naphthylene group. Cou is a coumarin-6-yl group or a coumarin-7-yl group, and part of the hydrogen atoms bonded thereto may be substituted with -NO ２ , -CN, -CH = C(CN) ２ . -CH = CH-CN, a halogen atom, an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. E is -C(=O)-O-, -O-C(=O)-, -C(=O)-S-, -S-C(=O)-, -C(=S)-S-, or -S-C(=S)-. G １ and G ２ are each independently N or CH. The hydrogen atoms in the ring structure in formulas (p1-1) to (p1-6) may be substituted with substituents selected from an alkyl group having 1 to 6 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, a haloalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a haloalkoxy group having 1 to 6 carbon atoms, a halogen atom, a cyano group and a nitro group. The dashed line is a bond.)

[0030] P１ When it is a phenylene group, some or all of the hydrogen atoms of the phenylene group may be substituted with a cyano group, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms. Y １ and Y ２ When Y and Y are each a phenylene group, some or all of the hydrogen atoms of each phenylene group may be substituted with a cyano group, a halogen atom, an alkyl group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.

[0031] The alkylene group having 1 to 30 carbon atoms may be linear, branched or cyclic. Specific examples thereof include a methylene group, an ethylene group, a propane-1,3-diyl group, a butane-1,4-diyl group, a pentane-1,5-diyl group, a hexane-1,6-diyl group, a heptane-1,7-diyl group, an octane-1,8-diyl group, a nonane-1,9-diyl group, a decane-1,10-diyl group, and the like.

[0032] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.

[0033] The alkyl group having 1 to 6 carbon atoms and the alkyl group having 1 to 5 carbon atoms may be either linear or branched. Specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, an n-pentyl group and the like.

[0034] Specific examples of the alkylcarbonyl group having 2 to 6 carbon atoms include a methylcarbonyl (acetyl) group, an ethylcarbonyl group, an n-propylcarbonyl group, an n-butylcarbonyl group, an n-pentylcarbonyl group and the like.

[0035] Specific examples of the alkoxy group having 1 to 6 carbon atoms and the alkoxy group having 1 to 5 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an n-pentyloxy group and the like.

[0036] Specific examples of the C5-C8 divalent alicyclic hydrocarbon group include the cyclopentanediyl group, cyclohexanediyl group, cycloheptanediyl group, and cyclooctanediyl group.

[0037] Specific examples of the cycloalkyl groups having 3 to 7 carbon atoms include cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl groups.

[0038] The C1-C3 alkyl group may be linear or branched, and specific examples include a methyl group, an ethyl group, an n-propyl group, and an isopropyl group.

[0039] The alkylene group having 1 to 12 carbon atoms may be linear, branched, or cyclic. Specific examples include methylene, ethylene, propane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, hexane-1,6-diyl, heptane-1,7-diyl, octane-1,8-diyl, nonane-1,9-diyl, and decane-1,10-diyl.

[0040] Examples of the monovalent organic group include a methyl group, an ethyl group, and a tert-butoxycarbonyl group.

[0041] As base p1, bases represented by the following formulas (p1-1-1), (p1-1-2), (p1-2-1), (p1-3-1), (p1-4-1), (p1-5-1), or (p1-6-1) are more preferred. Note that formulas (p1-1-1) and (p1-1-2) are examples of formula (p1-1). Formula (p1-2-1) is an example of formula (p1-2). Formula (p1-3-1) is an example of formula (p1-3). Formula (p1-4-1) is an example of formula (p1-4). Formula (p1-5-1) is an example of formula (p1-5). Formula (p1-6-1) is an example of formula (p1-6). (In the formula, L, A １ A ２ , Y １ , Y ２ , P １ Q １ , T １ , R, X １ Zａ Z ｂ Cou, E, G １ G ２ (The same applies to n1 and the dashed line as described above.)

[0042] The group represented by formula (p1-1-1) is preferably the group represented by the following formula (p1-1-1-1), and the group represented by formula (p1-1-2) is preferably the group represented by formula (p1-1-2-1). (In formulas (p1-1-1-1) and (p1-1-2-1), Z ｃ and Z ｄ Each of these is independently a hydrogen atom, a phenyl group, or an alkyl group having 1 to 3 carbon atoms. １ n3 is an alkyl group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms. n3 is an integer from 0 to 4. １ When the number is 2 or more, each W １ n1, L, and Q may be the same or different from each other. １ Q ２ , X １ , P １ (R and dashed lines are the same as above.)

[0043] The group represented by formula (p1-2-1) is preferably the group represented by the following formula (p1-2-1-1). (In formula (p1-2-1-1), W ２ n4 is an alkyl group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms. n4 is an integer from 0 to 4. W ２ When the number is 2 or more, each W ２ L and Q may be the same or different from each other. １ Q ２ , X １ A ２ , T １ Z ｃ Z ｄ , W １ (The same applies to n3, R, and the dashed line as described above.)

[0044] The group represented by formula (p1-3-1) is preferably the group represented by the following formulas (p1-3-1-1), (p1-3-1-2), or (p1-3-1-3). (In the formula, L, Cou, W １ , W ２ n3, n4, and the dashed line are the same as described above.

[0045] The group represented by formula (p1-4-1) is preferably the group represented by the following formulas (p1-4-1-1) or (p1-4-1-2). (In formulas (p1-4-1-1) to (p1-4-1-2), E １ and E ２ Each of these is independently either an oxygen atom or a sulfur atom. Note that L, R, and W are... １ , W ２ n3, n4, and the dashed line are the same as described above.

[0046] The group represented by formula (p1-5-1) is preferably the group represented by the following formulas (p1-5-1-1) or (p1-5-1-2). (In formulas (p1-5-1-1) to (p1-5-1-2), W ３ The group is an alkyl group having 1 to 5 carbon atoms, an alkylcarbonyl group having 2 to 6 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms, and n5 is an integer from 0 to 4. Note that L, R, W １ , W ２ n3, n4, and the dashed line are the same as described above.

[0047] The group represented by formula (p1-6-1) is preferably the group represented by the following formula (p1-6-1-1). (In the formula, L, R, G １ G ２ , W １ , W ２ n3, n4, and the dashed line are the same as described above.

[0048] As for the group having a photoreactive moiety, a group represented by the formula (p1-1-2) is preferably a terminal COOH group where R is H, and among these, Y １ A group in which the group is a 1,4-phenylene group is even more preferred.

[0049] Side-chain polymers have photosensitive side chains bonded to the main chain and can undergo crosslinking, isomerization, or Fries rearrangement in response to ultraviolet light. The structure of a photosensitive side-chain polymer capable of exhibiting liquid crystalline properties is not particularly limited as long as it satisfies these properties, but it is preferable that the side-chain structure has a rigid mesogenic component. When the side-chain polymer is used as a single-layer phase difference material, stable optical anisotropy can be obtained.

[0050] A more specific example of a photosensitive side-chain polymer structure capable of exhibiting liquid crystalline properties is a structure having a main chain derived from at least one selected from the group consisting of radical polymerizable groups such as (meth)acrylate, itaconate, fumarate, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, norbornene, and siloxane, and a side chain p containing a photosensitive group (p).

[0051] The polymer (P) preferably has a photosensitive group (p) and a side chain q represented by the following formula (q), which does not contain a photosensitive moiety. (In formula (q), L Ｂ L is a single-bonded, linear, or branched alkylene group having 1 to 30 carbon atoms, and one or more hydrogen atoms of the alkylene group may be substituted with a fluorine atom or a monovalent organic group. Ｂ CH inside ２ CH ２ The - can also be substituted with -CH=CH-, L Ｂ CH inside ２ -, -O-, -S-, -NR Ｌ -, -C(=O)-, -C(=O)-NR Ｌ -, -NR Ｌ -C(=O)-, and -NR Ｌ -C(=O)-NR Ｌ - (However, R Ｌ Each of these independently represents a hydrogen atom or a monovalent organic group. ) may be substituted with a group selected from the group consisting of ). However, adjacent -CH ２ - These groups cannot be substituted simultaneously. Q ＢThese are aromatic groups, polycyclic aromatic groups, alicyclic groups, phenylenecyclohexylene groups, heterocyclic groups, or fused cyclic groups. Q Ｂ When the number of Q is 2 or more, Ｂ They may be the same or different from each other. Ｂ This is a single bond, -CH ２ -, -O-, -S-, -C(=O)-, -NR Ｘ -, -C(=O)-O-, -C(=O)-NR Ｘ -, -NR Ｘ -C (=O)- or -NR Ｘ -C(=O)-NR Ｘ - (However, R Ｘ Each of these independently represents a hydrogen atom or a monovalent organic group. Ｂ When the number of X is 2 or more, Ｂ They may be the same or different from each other. Y Ａ R is a divalent group selected from aromatic groups, polycyclic aromatic groups, phenylenecyclohexylene groups, and biphenyl groups. Ｂ R is a single bond or an alkylene group having 1 to 10 carbon atoms, and one or more hydrogen atoms of the alkylene group may be substituted with a fluorine atom or an organic group. Ｂ CH inside ２ -ga, -O-, -NR Ｒ - (However, R Ｒ represents a hydrogen atom or a monovalent organic group. It may be substituted with a group selected from the group consisting of ) and -C(=O)-. Adjacent -CH ２ - may be substituted with these groups simultaneously. R Ｃ represents a hydrogen atom or a monovalent organic group. The hydrogen atom in the ring structure of formula (q) may be substituted with substituents selected from C1-C6 alkyl groups, C2-C6 alkylcarbonyl groups, C1-C6 haloalkyl groups, C1-C6 alkoxy groups, C1-C6 haloalkoxy groups, halogen atoms, cyano groups, and nitro groups. d is 0, 1, or 2. The dashed line represents a bond. However, L Ｂ Q Ｂ At the end of the side, -Q Ｂ -X Ｂ - * (* is Q) ＢIt does not have a structure represented by (representing a bonding relationship with).

[0052] Y Ａ In this, some or all of the hydrogen atoms of the aromatic ring may be substituted with an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, or a halogen atom.

[0053] The number of ring structures in the side chain represented by the above formula (q) is preferably three or less. Here, the ring structure of a fused ring is counted as one. That is, there is one ring structure in the phenylene group and naphthylene group, and two ring structures in the biphenylylene group and cyclohexanediyl group.

[0054] As the side chain q, for example, a side chain represented by the following formulas (q1) to (q5) is preferred. In formulas (q1) to (q5), L Ｂ Q Ｂ , X Ｂ , R Ｂ , R Ｃ , d, and the dashed line are equivalent to their definitions in equation (q), respectively. １ , W ２ n3 and n4 are equivalent to the definitions in equations (p1-1-1-1) and (p1-2-1-1), respectively.

[0055] The polymer (P) exhibits liquid crystalline properties in a temperature range of, for example, 80 to 300°C, and may further have a side chain (hereinafter also referred to as side chain r) that exhibits only liquid crystalline properties. Here, "exhibiting only liquid crystalline properties" means that a polymer having only side chain r does not exhibit photo-orientation properties during the fabrication process of the phase difference material of the present invention (i.e., steps (I) to (III) described later), and exhibits only liquid crystalline properties.

[0056] As the side chain r, one or two liquid crystalline side chains selected from the group consisting of the following formulas (r1) to (r8) are preferred.

[0057] In formulas (r1) to (r8), A ｒ１ , and A ｒ２ Each of these is independently a single bond, -O-, -S-, and -CH. ２-, -C(=O)-O-, -O-C(=O)-, -C(=O)-NH-, -NH-C(=O)-, or -C(=O)-NH-. R ｒ１ is, -NO ２ -CN, halogen atom, C1-C12 alkyl group or C1-C12 alkyloxy group. ｒ１ is -C(=O)-, -NH-, -NH-C(=O)-, or -C(=O)-NH-. d is an integer from 1 to 12. m1 and m2 are independently integers from 1 to 3, and m3 is an integer from 0 to 3. n is 0 or 1.

[0058] The side-chain polymer used in the present invention can be obtained by polymerizing a monomer that gives side chain p (a monomer compound having a photosensitive group (p) and a polymerizable group), a monomer that optionally gives side chain q, and a monomer that optionally gives side chain r.

[0059] Examples of monomer compounds having a photosensitive group (p) and a polymerizable group (hereinafter also referred to as monomer MA) include compounds represented by the following formulas (M1-1), (M1-2), (M1-3), (M1-4), (M1-5), or (M1-6). (In the formula, PG is a polymerizable group, A １ A ２ , D １ , L, T １ , Y １ , Y ２ , P １ Q １ Q ２ ,R,Cou,E,X １ , X ２ Z ａ Z ｂ G １ G ２ n1 and n2 are A in equations (p1-1) to (p1-6). １ A ２ , D １ , L, T １ , Y １ , Y ２ , P １ Q １ Q ２ ,R,Cou,E,X １ , X ２ Z ａ Zｂ G １ G ２ (These are the same as n1 and n2, respectively.)

[0060] In formulas (M1-1), (M1-2), (M1-3), (M1-4), (M1-5), and (M1-6), the following are preferred structures for the polymerizable group PG. However, it is not limited to these. (In the formula, R １ , and R ２ Each of the following independently represents a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, and X, Y, and Z independently represent an oxygen atom or a sulfur atom. * represents a bonding site. * １ and * ２ One of the elements represents a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms, while the other represents a bonding site.

[0061] As the compound represented by formula (M1-1), compounds represented by the following formulas (M1-1-1) and (M1-1-2) are preferred. (In the formula, PG, L, Q １ Q ２ , X １ , Y １ Z ａ Z ｂ , P １ (R and n1 are the same as above.)

[0062] As the compound represented by formula (M1-2), the compound represented by the following formula (M1-2-1) is preferred. (In the formula, PG, A ２ , L, T １ , Y １ Z ａ Z ｂ , P １ Q １ Q ２ (And R are the same as above.)

[0063] Of the compounds represented by formula (M1-3), the compound represented by the following formula (M1-3-1) is preferred. (In the formula, PG, A １ L, X １ Q １(Cou and n1 are the same as described above.)

[0064] Of the compounds represented by formula (M1-4), the compound represented by the following formula (M1-4-1) is preferred. (In the formula, PG, A １ L, X １ , Y １ , Y ２ Q １ (E, R, and n1 are the same as above.)

[0065] Of the compounds represented by formula (M1-5), the compound represented by the following formula (M1-5-1) is preferred. (In the formula, PG, A １ L, X １ , Y １ , Y ２ Q １ (R and n1 are the same as above.)

[0066] Of the compounds represented by formula (M1-6), the compound represented by the following formula (M1-6-1) is preferred. (In the formula, PG, A １ L, X １ , Y １ , Y ２ Q １ G １ G ２ (R and n1 are the same as above.)

[0067] The compound represented by formula (M1-1-1) is preferably the compound represented by the following formula (M1-1-1-1), and the compound represented by formula (M1-1-2) is preferably the compound represented by the following formula (M1-1-2-1). (In the formula, PG, n1, L, Q １ , X １ , R, Z ｃ Z ｄ , P １ Q ２ , W １ (And n3 are the same as above.)

[0068] As the compound represented by formula (M1-2-1), the compound represented by the following formula (M1-2-1-1) is preferred. (In the formula, PG, L, A ２ Q１ , T １ Z ｃ Z ｄ , R, P １ Q ２ , W ２ (And n4 are the same as above.)

[0069] As the compound represented by formula (M1-3-1), compounds represented by the following formulas (M1-3-1-1), (M1-3-1-2), or (M1-3-1-3) are preferred. (In the formula, PG, L, Cou, W １ , W ２ (n3 and n4 are the same as above.)

[0070] As the compound represented by formula (M-1-4-1), the compound represented by the following formulas (M1-4-1-1) or (M1-4-1-2) is preferred. (In the formula, PG, L, E １ , E ２ , R, W １ , W ２ (n3 and n4 are the same as above.)

[0071] As the compound represented by formula (M1-5-1), the compound represented by the following formulas (M1-5-1-1) or (M1-5-1-2) is preferred. (In the formula, PG, L, R, W １ , W ２ , W ３ (n3, n4, and n5 are the same as above.)

[0072] As the compound represented by formula (M1-6-1), the compound represented by the following formula (M1-6-1-1) is preferred. (In the formula, PG, L, R, G １ G ２ , W １ , W ２ (n3 and n4 are the same as above.)

[0073] Examples of compounds represented by formula (M1-1-1-1) include those represented by any of the following formulas (M1-1-1-1-1) to (M1-1-1-1-6). In the following formulas (M1-1-1-1-1) to (M1-1-1-1-6), PG is a polymerizable group, and s1 represents the number of methylene groups and is an integer from 2 to 9. ２ H is -H, -CH ３ , -OCH ３ , -C(=O)-OCH ３ Or -CN. W ４ , and W ５ Each of these is independently -CH ３ , or -OCH ３ That is. Z ｅ , and Z ｆ These are, independently, -H or -CH ３ n6 and n7 are each independent integers between 0 and 4. ４ When the number is 2 or more, each W ４ They may be the same or different from each other. ５ When the number is 2 or more, each W ５ They may be the same or different from each other.

[0074]

[0075] Examples of compounds represented by formula (M1-1-2-1) include those represented by any of the following formulas (M1-1-2-1-1) to (M1-1-2-1-6). In the following formulas, PG, s1, and W are used. ４ , W ５ Z ｅ Z ｆ (n6 and n7 are the same as described above.)

[0076] Compounds represented by formula (M1-2-1-1) include, for example, compounds represented by any of the following formulas (M1-2-1-1-1) to (M1-2-1-1-9). In the following formulas, s2 represents the number of methylene groups and is an integer from 2 to 9. In the following formulas, PG, s1, R ２ , W ４ , W ５ Z ｅ Z ｆ(n6 and n7 are the same as described above.)

[0077]

[0078] Examples of compounds represented by formula (M1-3-1-1) include compounds represented by any of the following formulas (M1-3-1-1-1) to (M1-3-1-1-2), examples of compounds represented by formula (M1-3-1-2) include compounds represented by any of the following formulas (M1-3-1-2-1) to (M1-3-1-2-2), and examples of compounds represented by formula (M1-3-1-3) include compounds represented by the following formula (M1-3-1-3-1). In the following formulas, PG, s1, and W are used. ４ , W ５ n6 and n7 are the same as described above.

[0079] Examples of compounds represented by formula (M1-4-1-1) include the compound represented by the following formula (M1-4-1-1-1), and examples of compounds represented by formula (M1-4-1-2) include the compound represented by the following formula (M1-4-1-2-1). In the following formulas, PG, s1, R ２ , W ４ , W ５ , E １ , E ２ n6 and n7 are the same as described above.

[0080] Examples of compounds represented by formula (M1-5-1-1) include the compound represented by the following formula (M1-5-1-1-1), and examples of compounds represented by formula (M1-5-1-2) include the compound represented by the following formula (M1-5-1-2-1). In the following formulas, PG, s1, R ２ , W ４ , W ５ n6 and n7 are the same as described above. W ６ is, -CH ３ , or -OCH ３ n8 is an integer between 0 and 4. ６ When the number is 2 or more, each W ６ They may be the same or different from each other.

[0081] Examples of compounds represented by formula (M1-6-1-1) include the compound represented by the following formula (M1-6-1-1-1). In the following formula, PG, s1, R ２ , W ４ , W ５ G １ G ２ n6 and n7 are the same as described above.

[0082] Some of the monomers are commercially available, while others can be produced by methods such as those described in International Publication No. 2014 / 054785.

[0083] As monomer compounds having a photosensitive group (p) and a polymerizable group, in the compounds represented by the above formulas (M1-1-1-1-1), (M1-1-1-1-2), and (M1-1-1-1-5), R is OCH ３ Compounds that are Z are preferred, among others ｅ , and Z ｆ Compounds in which both atoms are hydrogen atoms or one is a methyl group, and s1 is an integer between 2 and 8, are more preferred. Furthermore, PG is more preferably a methacrylic group (methacryloyloxy group), an acrylic group (acryloyloxy group), a styryl group, or a maleimide group.

[0084] Preferred examples of such monomers include compounds represented by the following formulas: (M1-1-1-1-1-1) to (M1-1-1-1-1-3), (M1-1-1-1-2-1) to (M1-1-1-1-2-3), and (M1-1-1-1-5-1) to (M1-1-1-1-5-3). In the following formulas, s1 represents an integer from 2 to 8.

[0085]

[0086]

[0087] Among monomer compounds having a photosensitive group (p) and a polymerizable group, the compounds represented by the above formulas (M1-1-2-1-1), (M1-1-2-1-2), (M1-1-2-1-4), (M1-1-2-1-5), (M1-1-2-1-6) are Z ｅ , and Zｆ Compounds in which both atoms are hydrogen atoms or one is a methyl group, and s1 is an integer between 2 and 8, are more preferred. Furthermore, PG is more preferably a methacrylic group, an acrylic group, a styryl group, or a maleimide group.

[0088] Preferred examples of such monomers include compounds represented by the following formulas: (M1-1-2-1-1-1) to (M1-1-2-1-1-3), (M1-1-2-1-2-1) to (M1-1-2-1-2-3), (M1-1-2-1-4-1) to (M1-1-2-1-4-3), (M1-1-2-1-5-1) to (M1-1-2-1-5-3), and (M1-1-2-1-6-1) to (M1-1-2-1-6-3). In the following formulas, s1 represents an integer from 2 to 8.

[0089]

[0090]

[0091]

[0092]

[0093] As monomer compounds having a photosensitive group (p) and a polymerizable group, in the compounds represented by the above formulas (M1-2-1-1-2), (M1-2-1-1-4), and (M1-2-1-1-5), Z ｅ , and Z ｆ Compounds in which both atoms are hydrogen atoms or one is a methyl group, and s1 is an integer between 2 and 8, are more preferred. Furthermore, PG is more preferably a methacrylic group, an acrylic group, a styryl group, or a maleimide group.

[0094] Preferred examples of such monomers include compounds represented by the following formulas: (M1-2-1-1-2-1) to (M1-2-1-1-2-3), (M1-2-1-1-4-1) to (M1-2-1-1-4-3), and (M1-2-1-1-5-1) to (M1-2-1-1-5-3). In the following formulas, s1 represents an integer from 2 to 8.

[0095]

[0096]

[0097]

[0098] Examples of monomers having the structure represented by formula (q) (hereinafter also referred to as monomer MB) include the compound represented by the following formula (MB1). (In the formula, PG, L Ｂ Q Ｂ , X Ｂ , Y Ａ , R Ｂ , R Ｃ and d are PG and L in formula (q). Ｂ Q Ｂ , X Ｂ , Y Ａ , R Ｂ , R Ｃ (These are the same as and d, respectively.) The hydrogen atoms in the ring structure of the formula may be substituted with substituents selected from C1-C6 alkyl groups, C2-C6 alkylcarbonyl groups, C1-C6 haloalkyl groups, C1-C6 alkoxy groups, C1-C6 haloalkoxy groups, halogen atoms, cyano groups, and nitro groups.

[0099] As monomer MB, in the compound represented by formula (MB1) above, R Ｃ A compound represented by the following formula (MB1A), in which H is preferred. (In the formula, PG, L Ｂ Q Ｂ , X Ｂ , Y Ａ , R Ｂ And d are the same as described above. The hydrogen atoms in the ring structure in the formula may be substituted with substituents selected from C1-C6 alkyl groups, C2-C6 alkylcarbonyl groups, C1-C6 haloalkyl groups, C1-C6 alkoxy groups, C1-C6 haloalkoxy groups, halogen atoms, cyano groups, and nitro groups.

[0100] The monomer MB1A is preferably a compound represented by the following formulas (MB1A-1) to (MB1A-21) (where p is an integer from 2 to 9), and more preferably a compound represented by the following formulas (MB1A-1) to (MB1A-21) (where p is an integer from 2 to 8). Furthermore, the PG is more preferably a methacrylic group, an acrylic group, a styryl group, or a maleimide group.

[0101]

[0102]

[0103]

[0104] Some of these monomers are commercially available, while others can be produced from known substances by known manufacturing methods.

[0105] A monomer having a structure that exhibits liquid crystalline properties only in the side chain r (hereinafter also referred to as monomer MC) is a monomer from which a polymer can exhibit liquid crystalline properties.

[0106] The mesogenic group of the side chain r is preferably a monovalent group obtained by removing one hydrogen atom from the ring structure in the structure represented by any of the following formulas (meso1) to (meso10). (In the above formulas (meso1) to (meso10), R ３ This is a hydrogen atom, -OCH ３ , -C(=O)-O-CH ３ (It is a cyano group or a halogen atom.)

[0107] More specific examples of monomer MCs include structures having a polymerizable group derived from at least one selected from the group consisting of radical polymerizable groups such as (meth)acrylate, itaconate, fumarate, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, norbornene, and siloxane, and at least one of the above formulas (meso1) to (meso10). In particular, monomer MCs having (meth)acrylate as a polymerizable group are preferred.

[0108] Preferred examples of monomer MCs include compounds represented by the following formulas (MC-1) to (MC-9).

[0109] (In the formula, PG is more preferably a methacrylic group, an acrylic group, a styryl group, or a maleimide group, and compounds in which p is an integer from 2 to 8 are even more preferred. Me represents a methyl group.)

[0110] Furthermore, monomer MD can be copolymerized to introduce a non-crystalline side chain d into the polymer (P) to the extent that it does not impair the photoreactivity and / or liquid crystalline properties. Examples of monomer MD include industrially available radical polymerization-reactive monomers. Specific examples include unsaturated carboxylic acids, acrylic acid ester compounds, methacrylic acid ester compounds, maleimide compounds, acrylonitrile, maleic anhydride, styrene compounds, vinyl compounds, acrylamide compounds, methacrylamide compounds, and the like.

[0111] Specific examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid.

[0112] Examples of acrylic acid ester compounds include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthyl acrylate, anthyl methyl acrylate, phenyl acrylate, 2,2,2-trifluoroethyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, 8-ethyl-8-tricyclodecyl acrylate, 2-hydroxyethyl acrylate, and 4-hydroxybutyl acrylate.

[0113] Examples of methacrylic acid ester compounds include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthyl methacrylate, anthyl methyl methacrylate, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, 8-ethyl-8-tricyclodecyl methacrylate, 2-hydroxyethyl methacrylate, and glycidyl methacrylate.

[0114] Examples of maleimide compounds include N-benzylmaleimide, 4-maleimidobutyric acid, N-methoxycarbonylmaleimide, and N-cyclohexylmaleimide.

[0115] Examples of styrene compounds include styrene, 4-methylstyrene, 4-vinylphenylboronic acid, 4-vinylbenzoic acid, and trans-anethole.

[0116] Examples of vinyl compounds include vinyl ether, methyl vinyl ether, benzyl vinyl ether, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and propyl vinyl ether. Examples of styrene compounds include styrene, 4-methylstyrene, 4-chlorostyrene, and 4-bromostyrene. Examples of maleimide compounds include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

[0117] Examples of acrylamide compounds include acrylamide, N,N-dimethylacrylamide, N-(hydroxymethyl)acrylamide, N-isopropylacrylamide, N-propylacrylamide, N-tert-butylacrylamide, N-(methoxymethyl)acrylamide, and N-(butoxymethyl)acrylamide.

[0118] Examples of methacrylamide compounds include N-methylmethacrylamide, N,N-dimethylmethacrylamide, N-(hydroxymethyl)methacrylamide, N-(methoxymethyl)methacrylamide, N-(butoxymethyl)methacrylamide, and N-(4-hydroxyphenyl)methacrylamide.

[0119] In the polymer (p) of the present invention, the content of side chain p is preferably 5 to 90 mol%, more preferably 5 to 80 mol%, and even more preferably 5 to 50 mol%, as the ratio of structural units having side chain p to the total structural units, from the viewpoint of photoreactivity.

[0120] From the viewpoint of phase difference, the content of side chain q in the polymer (p) of the present invention is preferably 10 to 95 mol% as the ratio of structural units having side chain q to the total structural units.

[0121] In the polymer (p) of the present invention, the content of side chain r is the maximum amount when the sum of the content of side chain p and side chain q is less than 100 mol%, as the ratio of the total number of structural units having side chain p and structural units having side chain q to the total number of structural units.

[0122] As described above, the polymer (p) of the present invention may contain a non-crystalline component side chain d. The content of side chain d is the remaining portion when the total content of side chains p, q, and r is less than 100 mol% of the total structural units, which are structural units having side chain p, structural units having side chain q, and structural units having side chain r.

[0123] Polymer (P) can be produced by polymerizing monomer MA, optionally monomer MB, optionally monomer MC, and optionally monomer MD in the presence of the polymerization control agent (A), which is a reversible addition-cleavage chain transfer (RAFT) polymerization reagent, and a radical polymerization initiator.

[0124] When synthesizing polymers using RAFT polymerization, examples of polymerization initiators to be used include 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, 1,1'-bis(t-butylperoxy)cyclohexane, and hydrogen peroxide. The proportion of polymerization initiator used is usually 0.000001 to 0.1 moles, preferably 0.00001 to 0.01 moles, per mole of monomer used. Preferred polymerization regulators (RAFT agents) are trithiocarbonates, dithiobenzoates, dithiocarbamates, and xanthanates, and specific examples include the compound represented by polymerization regulator (A) above. The proportion of polymerization regulator used is usually 0.000001 to 0.1 moles, preferably 0.00001 to 0.01 moles, per mole of monomer used. The reaction temperature in the polymerization described above is preferably 20 to 200°C, more preferably 40 to 150°C, and the reaction time is preferably 1 to 168 hours, more preferably 8 to 72 hours.

[0125] Living radical activity in RAFT polymerization occurs because, as the majority of the living chain is dormant (resting), there are compounds that can reversibly inactivate the growing radical species, and a rapid equilibrium exists between the active chain and the dormant chain.

[0126] Using RAFT polymerization enables precise control of polymer end structures, advanced molecular weight control, and molecular weight distribution control.

[0127] To precisely synthesize functional polymers using RAFT polymerization, it is necessary to select an appropriate chain transfer agent considering the reactivity of the monomers.

[0128] In RAFT polymerization, molecular weight control is possible by using the following formula (eq1). Specifically, the number-average molecular weight (Mn) changes linearly with the ratio of the molar concentration of the monomer to the molar concentration of the chain transfer agent, thus enabling molecular weight control.

[0129] (In the above formula (eq1), Mn （ｔｈｅｏｒ） The symbol represents the molecular weight of the polymer, and [Monomer] ０ [CTA] represents the molar concentration of monomer. ０ represents the molar concentration of the chain transfer agent, M ｍｏｎｏｍｅｒ represents the molecular weight of the monomer, and conv. represents the polymerization conversion rate. ＣＴＡ (This represents the molecular weight of the chain transfer agent.)

[0130] In RAFT polymerization, the polymer ends can be controlled by thermally or chemically modifying the RAFT ends present at the growth ends. Thermal modification involves heating to a temperature above the thermal decomposition temperature of the RAFT agent used, thereby modifying the ends into unsaturated hydrocarbon groups. Chemical modification involves contact with primary or secondary amines, which leads to aminolysis and modification of the ends into thiol bonds. Furthermore, contact with new monomers and radical generators allows for the creation of new block segments at the ends.

[0131] For radical polymerization, known compounds such as radical polymerization initiators (radical thermal polymerization initiators, radical photopolymerization initiators, etc.) can be used as polymerization initiators.

[0132] Radical thermal polymerization initiators are compounds that generate radicals when heated above their decomposition temperature. Examples of such radical thermal polymerization initiators include ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydroperoxides (hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), and peroxyketals. Examples include dibutylperoxycyclohexane, alkyl peresters (tert-butyl peroxyneodecanoate, tert-butyl peroxypivalate, tert-amyl peroxy-2-ethylcyclohexanoate, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), and azo compounds (azobisisobutyronitrile, 2,2'-di(2-hydroxyethyl)azobisisobutyronitrile, 2,2'-azobis(2-methylpropionic acid)dimethyl, etc.). Radical thermal polymerization initiators may be used alone or in combination of two or more.

[0133] The radical photopolymerization initiator is not particularly limited as long as it is a compound that initiates radical polymerization by light irradiation. Examples of such radical photopolymerization initiators include benzophenone, Michla's ketone, 4,4'-bis(diethylamino)benzophenone, xanthone, thioxanthone, isopropylxanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexylphenyl ketone, isopropylbenzoin ether, isobutylbenzoin ether, 2 ,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzantrone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 4-ethyl dimethylaminobenzoate, 4-isoamyl dimethylaminobenzoate, 4,4'-di(tert-butylperoxycarbonyl)benzophenone, 3,4,4'-tri(tert-butylperoxy Carbonyl benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-pentyloxy Styryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[p-N,N-di(ethoxycarbonylmethyl)]-2,6-di(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-mercaptobenzothiazole, 3,3'-Carbonylbis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'bis(2 ,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3,6-bis(2-methyl-2-morpholinopropionyl)-9-n-dodecylcarbazole, 1-hydroxycyclohexylphenyl ketone, Bis(5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole-1-yl)-phenyl)titanium,3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone,3,3',4,4'-tetra(t-hexylperoxycarbonyl)benzophenone,3,3'-di(methoxycarbonyl)-4,4'-di(t-butylperoxycarbonyl)benzophenone,3,4'- Examples include di(methoxycarbonyl)-4,3'-di(t-butylperoxycarbonyl)benzophenone, 4,4'-di(methoxycarbonyl)-3,3'-di(t-butylperoxycarbonyl)benzophenone, 2-(3-methyl-3H-benzothiazole-2-ylidene)-1-naphthalene-2-yl-ethanone, and 2-(3-methyl-1,3-benzothiazole-2(3H)-ylidene)-1-(2-benzoyl)ethanone. The radical photopolymerization initiator may be used alone or in combination of two or more.

[0134] The polymerization method is not particularly limited, and emulsion polymerization, suspension polymerization, dispersion polymerization, precipitation polymerization, bulk polymerization, solution polymerization, etc., can be used.

[0135] The organic solvent used in the polymerization reaction is not particularly limited as long as it does not chemically react with the compound species constituting the copolymer and does not scavenge radicals. Specific examples include N,N-dimethylformamide, N,N-diethylformamide, N,N-dibutylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dipropylacetamide, N,N-dimethylpropionamide, N,N-diethylpropionamide, 3-methoxy-N,N-dimethylpropanamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-Dimethyl-2-imidazolidinone, N-methyl-ε-caprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethylphosphoramide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellosolve), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol Lu-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1,4-Dioxane, n-Hexane, n-Pentane, n-Octane, Cyclohexane, 2-Ethyl-1-Hexanol, Benzene, Xylene, Toluene, Ethylbenzene, Isopropylbenzene, Tert-Butylbenzene, Tetrahydrofuran, Diethyl Ether, Cyclohexanone, Ethylene Carbonate, Propylene Carbonate, Methyl Lactate, Ethyl Lactate, Methyl Acetate, Ethyl Acetate, N-Butyl Acetate, Propylene Glycol Monoethyl Ether Acetate, Methyl Pyruvate, Ethyl Pyruvate, Methyl 3-Methoxypropionate, Ethyl 3-Methoxypropionate, Methyl 3-Ethoxypropionate, Ethyl 3-Ethoxypropionate, Ethoxypropionic Acid, 3-Methoxypropionic Acid, Propyl 3-Methoxypropionate, Butyl 3-Methoxypropionate, Diglyceride, 4-Hydroxy-4-Methyl-2-Pentanone, 3-Ethoxy-N,N-Dimethylpropanamide, 3-Butoxy-N,N-dimethylpropanamide, propyl pyruvate, butyl pyruvate, pentyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, ethyl levulinate, propyl levulinate, butyl levulinate, pentyl levulinate, hexyl levulinate, 2-ethylhexyl levulinate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate Examples include dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipentyl malonate, dipentyl succinate, dipentyl glutarate, dipentyl adipate, dipentyl phthalate, dipentyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, and 2-ethylhexyl maleate.

[0136] The aforementioned organic solvent may be used alone or as a mixture of two or more. Furthermore, even a solvent that does not dissolve the polymer to be produced may be mixed with the aforementioned organic solvent, as long as the polymer does not precipitate. In addition, since oxygen in the organic solvent inhibits the polymerization reaction in radical polymerization, it is preferable to use an organic solvent that has been degassed to the extent possible.

[0137] The polymerization temperature can be selected from any temperature between 30 and 150°C, but is preferably in the range of 50 to 100°C. The reaction can be carried out at any concentration, but if the concentration is too low, it becomes difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high, making uniform stirring difficult. Therefore, the monomer concentration is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction can be carried out at a high concentration in the initial stages, and then an organic solvent can be added.

[0138] During the radical polymerization process, the polymerization control agent (A) remains in the polymer with a -C(=S)-S- moiety bonded to the end portion of the polymer, and this functions as a dormant species. Therefore, when there is a large amount of polymerization control agent (A), the number of end portions increases and the molecular weight decreases, and when there is a small amount of polymerization control agent (A), the number of end portions decreases and the molecular weight increases. The amount of polymerization control agent (A) is best controlled according to the desired molecular weight, and in the present invention, it is preferably 0.01 to 1.0 mol% relative to the monomer to be polymerized.

[0139] In the polymerization reaction described above, the polymerization control agent (A) determines the approximate molecular weight, so the influence of the polymerization initiator ratio is minor. However, the amount of polymerization initiator greatly affects the control ability of the polymerization control agent, so it is necessary to use an appropriate amount. In the present invention, it is preferable that the amount is 0.1 mole to 5.0 moles relative to the polymerization control agent (A).

[0140] To recover the polymer produced from the reaction solution obtained by the above reaction, the reaction solution can be placed in a poor solvent to precipitate the polymer. Examples of poor solvents that can be used for precipitation include methanol, acetone, hexane, heptane, butyl cellosolve, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, and water. The polymer precipitated in the poor solvent can be recovered by filtration and then dried at room temperature or by heating under atmospheric pressure or reduced pressure. Furthermore, the amount of impurities in the polymer can be reduced by repeating the operation of redissolving the recovered polymer in an organic solvent and reprecipitating it 2 to 10 times. Examples of poor solvents in this case include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more poor solvents selected from these to further increase the efficiency of purification.

[0141] The polymer (P) used in the present invention is preferably one whose weight-average molecular weight, measured by GPC (Gel Permeation Chromatography), is 2,000 to 2,000,000, more preferably 2,000 to 1,000,000, and even more preferably 5,000 to 500,000, considering the strength of the resulting coating film, workability during coating film formation, and uniformity of the coating film.

[0142] The polymer (P) exhibits a narrower polydispersity (PDI: weight-average molecular weight / number-average molecular weight) compared to polymers produced without polymerization control agents. The polydispersity of polymer (P) is preferably 2.5 or less, and more preferably 2.0 or less. There is no particular lower limit to the polydispersity, but it may be 1.0 or higher, 1.3 or higher, or 1.5 or higher.

[0143] The content of polymer (P) in the phase difference film-forming composition is not particularly limited, but is preferably 20 to 100% by mass, more preferably 40 to 100% by mass, and particularly preferably 60 to 100% by mass, relative to the film components. Film components refer to components other than the solvent in the phase difference film-forming composition.

[0144] [Organic solvent] The phase difference film-forming composition of the present invention includes, for example, an organic solvent (good solvent). The organic solvent (good solvent) is not particularly limited as long as it is an organic solvent that dissolves the polymer components. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethylphosphoramide, γ-butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone Ton, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl Dipropyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane,n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate monoethyl ether, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentane Tanone, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, 2-ethyl-1,3-hexanediol, ethylene glycol, propylene glycol (1,2-propanediol), 1,3-propanediol 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1,5-pentanediol, 2-methyl-2,4-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,6-hexanediol, 2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 3,5-hexanediol, 1,2-heptane glyco 1,3-heptanediol, 1,4-heptanediol, 1,5-heptanediol, 1,6-heptanediol, 1,7-heptanediol, 1,2-octanediol, 1,4-octanediol, 1,8-octanediol, 1,2-nonanediol, 1,3-nonanediol, 1,5-nonanediol, 1,6-nonanediol, 1,9-nonanediol, 1,2-decanediol, 1,5-decanediol, 1,8-decanediol, 1,10-decanediol, 1,2-cyclohexanediol, 1,3-cyclohexanediol,1,4-Cyclohexanediol, diethylene glycol, dipropylene glycol, dibutylene glycol, glycerol, 2-ethyl-1-hexanol, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, pentyl pyruvate, hexyl pyruvate, 2-ethylhexyl pyruvate, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, ethyl levulinate, propyl levulinate, butyl levulinate, pentyl levulinate, hexyl levulinate, 2-ethylhexyl levulinate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate, diethyl malonate, diethyl succinate, diethyl glutarate, Diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipentyl malonate, dipentyl succinate, dipentyl glutarate, dipentyl adipate Examples include dipentyl phthalate, dipentyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, and 2-ethylhexyl maleate. These may be used individually or in combination of two or more.

[0145] Furthermore, the phase difference film-forming composition may contain components other than the polymer (P) and the organic solvent (good solvent). Examples of such components include, but are not limited to, solvents (poor solvents) or compounds that improve film thickness uniformity and surface smoothness when the phase difference film-forming composition is applied, and compounds that improve adhesion between the phase difference film and the substrate.

[0146] Specific examples of solvents (poor solvents) that improve the uniformity of film thickness and surface smoothness include isopropyl alcohol, methoxymethyl pentanol, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether (butyl cellosolve), propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, and dipropylene Glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n- Octane, diethyl ether, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol acetate monoethyl ether, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol,1-Phenoxy-2-propanol, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, 2-ethyl-1-hexanol, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, pentyl pyruvate, hexyl pyruvate, pyruvate-2 - Ethylhexyl, methyl acetoacetate, ethyl acetoacetate, propyl acetoacetate, butyl acetoacetate, pentyl acetoacetate, hexyl acetoacetate, 2-ethylhexyl acetoacetate, methyl levulinate, ethyl levulinate, propyl levulinate, butyl levulinate, pentyl levulinate, hexyl levulinate, 2-ethylhexyl levulinate, dimethyl malonate, dimethyl succinate, dimethyl glutarate, dimethyl adipate, dimethyl phthalate, dimethyl maleate Diethyl malonate, diethyl succinate, diethyl glutarate, diethyl adipate, diethyl phthalate, diethyl maleate, dipropyl malonate, dipropyl succinate, dipropyl glutarate, dipropyl adipate, dipropyl phthalate, dipropyl maleate, dibutyl malonate, dibutyl succinate, dibutyl glutarate, dibutyl adipate, dibutyl phthalate, dibutyl maleate, dipentyl malonate, dipentyl succinate, dipentyl glutarate Examples of solvents with low surface tension include dipentyl adipate, dipentyl phthalate, dipentyl maleate, dihexyl malonate, dihexyl succinate, dihexyl glutarate, dihexyl adipate, dihexyl phthalate, dihexyl maleate, di-2-ethylhexyl malonate, 2-ethylhexyl succinate, 2-ethylhexyl glutarate, 2-ethylhexyl adipate, 2-ethylhexyl phthalate, and 2-ethylhexyl maleate.

[0147] The poor solvent may be used alone or as a mixture of two or more. When a poor solvent is used, its content is preferably 5 to 80% by mass, and more preferably 10 to 60% by mass, in the solvent so as not to significantly reduce the solubility of the polymer.

[0148] Compounds that improve film thickness uniformity and surface smoothness include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. Specific examples include F-Top® 301, EF303, EF352 (manufactured by Tochem Products), Megafac® F171, F173, F560, F563, R-30, R-40, R-41 (manufactured by DIC), Florard FC430, FC431 (manufactured by 3M), Asahiguard® AG710 (manufactured by AGC), and Surflon® S-382. Examples include SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC Seimi Chemical Co., Ltd.), BYK-302, BYK-306, BYK-307, BYK-325N, BYK-331, BYK-333, BYK-348, BYK-360N, BYK-361N, BYK-377, BYK-378, BYK-381, BYK-3441 (manufactured by BYK Co., Ltd.), etc. The content of these surfactants is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass, per 100 parts by mass of component (A).

[0149] Specific examples of compounds that improve the adhesion between the phase difference material and the substrate include functional silane-containing compounds.

[0150] Furthermore, in order to improve the adhesion between the substrate and the phase difference material, and to prevent the deterioration of properties due to backlighting when a polarizing plate is formed, phenoplast compounds or epoxy group-containing compounds may be added to the phase difference film forming composition.

[0151] When using a compound to improve adhesion to the substrate, its content is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the phase difference film forming composition. If the content is less than 0.1 parts by mass, the effect of improving adhesion cannot be expected, and if it is more than 30 parts by mass, the orientation of the liquid crystal may deteriorate.

[0152] Photosensitizers can also be used as additives. Colorless sensitizers and triplet sensitizers are preferred as photosensitizers.

[0153] In addition to those described above, the phase difference film forming composition of the present invention may also contain dielectrics, conductive materials, and crosslinking compounds, to change the electrical properties of the phase difference material, such as dielectric constant and conductivity, as long as the effects of the present invention are not impaired.

[0154] [Preparation of the Phase Difference Film Forming Composition] The phase difference film forming composition of the present invention is preferably prepared as a coating solution suitable for forming a single-layer phase difference material. That is, the phase difference film forming composition used in the present invention is preferably prepared as a solution in which a polymer (P) and a solvent or compound that improves the uniformity of film thickness and surface smoothness as described above, and a compound that improves the adhesion between the phase difference material and the substrate are dissolved in an organic solvent. Here, the content of polymer (P) is preferably 1 to 30% by mass, and more preferably 5 to 30% by mass, in the phase difference film forming composition of the present invention.

[0155] The phase difference film-forming composition of the present invention may contain other polymers in addition to polymer (P), as long as they do not impair the liquid crystal expression ability and photosensitive performance. In this case, the content of the other polymers in the polymer component is preferably 0.5 to 80% by mass, more preferably 1 to 50% by mass. Examples of the other polymers include polymers that are not photosensitive side-chain polymers capable of exhibiting liquid crystal properties, such as poly(meth)acrylate, polyamic acid, and polyimide.

[0156] [Resin film, single-layer phase difference material, method for manufacturing single-layer phase difference material] The resin film of the present invention is formed from the phase difference film forming composition of the present invention. The resin film can be obtained, for example, by step (I) described later. The single-layer phase difference material of the present invention can be manufactured by a method including the following steps (I) to (III). Step (I): A step of applying the phase difference film forming composition of the present invention onto a substrate to form a coating film. Step (II): A step of irradiating the coating film with polarized ultraviolet light. Step (III): A step of heating the coating film irradiated with ultraviolet light to obtain a single-layer phase difference material.

[0157] [Step (I)] Step (I) is a step of forming a coating film by applying the phase difference film-forming composition of the present invention onto a substrate. More specifically, the phase difference film-forming composition of the present invention is applied to a substrate such as a substrate (e.g., silicon / silicon dioxide coated substrate, silicon nitride substrate, glass substrate coated with metal (e.g., aluminum, molybdenum, chromium, etc.), glass substrate, quartz substrate, ITO substrate, etc.) or a film (e.g., triacetylcellulose (TAC) film, cycloolefin polymer (COP) film, polyethylene terephthalate film, resin film such as acrylic film) by methods such as bar coating, spin coating, flow coating, roll coating, slit coating, spin coating following slit coating, inkjet method, or printing method. After application, the solvent can be evaporated at 50 to 200°C, preferably 50 to 150°C, using a heating means such as a hot plate, hot air circulation oven, or IR (infrared) oven to obtain a coating film.

[0158] [Step (II)] In Step (II), polarized ultraviolet light is irradiated onto the coating film obtained in Step (I). When irradiating the surface of the coating film with polarized ultraviolet light, the polarized ultraviolet light is irradiated onto the substrate from a certain direction via a polarizing plate. As the ultraviolet light, ultraviolet light in the wavelength range of 100 to 400 nm can be used. Preferably, the optimal wavelength is selected via a filter or the like depending on the type of coating film used. For example, ultraviolet light in the wavelength range of 290 to 400 nm can be selected and used so that a photocrosslinking reaction can be selectively induced. As the ultraviolet light, for example, light emitted from a high-pressure mercury lamp can be used.

[0159] The amount of polarized ultraviolet light irradiated depends on the coating film used. Preferably, the irradiation amount is within the range of 1 to 70%, and more preferably within the range of 1 to 50%, of the amount of polarized ultraviolet light that achieves the maximum value of ΔA, which is the difference between the ultraviolet absorbance in the direction parallel to the polarization direction of the polarized ultraviolet light and the ultraviolet absorbance in the direction perpendicular to the polarization direction of the polarized ultraviolet light in the coating film.

[0160] [Process (III)] In process (III), the coating film that was irradiated with polarized ultraviolet light in process (II) is heated. Heating imparts orientation control capability to the coating film.

[0161] Heating can be performed using methods such as a hot plate, a hot air circulation oven, or an IR (infrared) oven. The heating temperature can be determined considering the temperature required to bring out the liquid crystal properties of the coating film being used.

[0162] The heating temperature is preferably within the temperature range at which the polymer (P) contained in the phase difference film-forming composition of the present invention exhibits liquid crystalline properties (hereinafter referred to as the liquid crystal appearance temperature). In the case of thin film surfaces such as coatings, the liquid crystal appearance temperature on the coating surface is expected to be lower than the liquid crystal appearance temperature when the polymer (P) is observed in bulk. Furthermore, these are expected to vary considerably depending on the thickness of the coating. In addition, it is expected that the liquid crystal temperature range of the material will decrease due to photoreactions induced by ultraviolet irradiation. For these reasons, the optimal heating temperature cannot be stated definitively as it depends on the material and the external environment, but it may be lower than the lower limit temperature of the liquid crystal appearance temperature range obtained from actual bulk observations. If the heating temperature is lower than the optimal temperature range, the thermal anisotropy amplification effect in the coating tends to be insufficient, and if the heating temperature is too high, the state of the coating tends to approach an isotropic liquid state (isotropic phase), in which case it may be difficult for it to reorient in one direction by self-assembly.

[0163] The liquid crystal emergence temperature is defined as a temperature above the liquid crystal transition temperature at which the polymer or coating surface undergoes a phase transition from the solid phase to the liquid crystal phase, and below the isotropic phase transition temperature (Tiso) at which a phase transition occurs from the liquid crystal phase to the isotropic phase. For example, exhibiting liquid crystal properties at 130°C or below means that the liquid crystal transition temperature at which the phase transition from the solid phase to the liquid crystal phase occurs is 130°C or below.

[0164] The thickness of the coating film formed after heating can be appropriately selected considering the unevenness and optical properties of the substrate used, for example, 0.5 to 10 μm is preferred.

[0165] The single-layer phase difference material obtained in this manner is a material with optical properties suitable for applications such as display devices and recording materials, and is particularly suitable as an optical compensation film for polarizing plates and phase difference plates of liquid crystal displays and organic EL displays.

[0166] The present invention will be described more specifically below with reference to synthesis examples, preparation examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0167] The monomers used in the examples are shown below. Note that the side chain derived from MA-1 is included in the range of side chain p, and the side chain derived from MB-1 is included in the range of side chain q. (Me represents a methyl group.)

[0168] (RAFT agent) (Et represents an ethyl group.) R-1, R-3, R-7, R-15, R-19, and R-21 are included in the range of polymerization control agents (A).

[0169] The abbreviations for the reagents used in this example are as follows: (Organic solvent) CPN: Cyclopentanone NMP: N-methyl-2-pyrrolidone (Polymerization initiator) AIBN: 2,2'-azobisisobutyronitrile

[0170] (Molecular Weight Measurement) (THF-GPC) The molecular weights of polyimide precursors and synthetic polymers other than polyimides were measured using a room-temperature gel permeation chromatography (GPC) apparatus (CBM-20A) (Shimadzu Corporation) and columns (Shodex® KF-804L and KF-803L in series) (Resonac Corporation) as follows: Column temperature: 40°C Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Standard samples for calibration curve preparation: Standard polystyrene (molecular weight: 197,000, 55,100, 12,800, 3,950, 1,260) (Tosoh Corporation)

[0171] [1] Synthesis of Polymers <Synthesis Example 1> MA-1 (4.00 g, 12.0 mmol), MB-1 (20.9 g, 68.2 mmol), R-1 (20.6 mg, 0.0642 mmol), AIBN (10.5 mg, 0.0642 mmol), and NMP (37.4 g) were weighed into a 100 ml two-necked flask and stirred at room temperature for 20 minutes to dissolve. The reaction solution was purged with nitrogen by nitrogen bubbling and then heated and stirred in an oil bath set to 60°C for 24 hours. After heating and stirring, the reaction solution was added to methanol (300 g) and the polymer was reprecipitated. Subsequently, the polymer was washed by filtration and methanol washing three times and dried to obtain polymer powder LR-1. The obtained polymer had an Mw of 312,200 and a PDI of 1.6.

[0172] <Synthesis Examples 2-24> As shown in Tables 1-1 and 1-2 below, polymer powders LR-2 to LR-23 were obtained by performing the same procedure as in Synthesis Example 1, except that the type and amount (g) of monomer used, the type and amount (g) of RAFT agent, and the amount of AIBN were changed.

[0173] <Synthesis Example 10> MA-1 (4.00 g, 12.0 mmol), MB-1 (20.9 g, 68.2 mmol), AIBN (92.2 mg, 0.562 mmol), and NMP (58.1 g) were weighed into a 100 ml two-necked flask and stirred at room temperature for 20 minutes to dissolve. The reaction solution was purged with nitrogen by nitrogen bubbling, and then heated and stirred in an oil bath set to 60°C for 24 hours. After heating and stirring, the reaction solution was added to methanol (300 g) and the polymer was reprecipitated. Subsequently, the polymer powder FR-1 was obtained by washing by filtration and methanol washing repeated three times and then drying. The obtained polymer had an Mw of 163,300 and a PDI of 3.2.

[0174] <Synthesis Examples 25-38> As shown in Tables 1-1 and 1-2 below, polymer powders FR-2 to FR-15 were obtained by performing the same procedure as in Synthesis Example 10, except that the type and amount (g) of monomer used and the amount of AIBN were changed.

[0175]

[0176]

[0177] [2] Preparation of phase difference film forming material <Preparation example 1> 1.4 g of polymer powder LR-1 obtained in synthesis example 1 was mixed with 8.6 g of CPN. This was filtered through a 5.0 μm pore size filter to obtain polymer preparation solution PD-1. This polymer preparation solution PD-1 was used as is as a coating solution for forming a phase difference film.

[0178] <Preparation Examples 2-38> Using the polymer powders LR-1 to LR-23 and FR-1 to FR-15 obtained in Synthesis Examples 2-38, polymer preparation solutions PD-2 to PD-38 were obtained in the same manner as in Preparation Example 1.

[0179]

[0180]

[0181] [3] Manufacturing of a single-layer phase difference film <Example 1> Polymer preparation solution PD-1 was applied to a COP film substrate using a bar coater to a thickness of approximately 3.6 μm. This substrate was dried in a hot air circulating oven at 50°C for 3 minutes (first drying), and then exposed to ultraviolet light at a wavelength of 365 nm at 100 mJ / cm² from a high-pressure mercury lamp through a cut filter (325 nm low-cut filter) and a polarizing plate. ２ The substrate was irradiated with [a specific light source]. It was then heated in an IR oven at 140°C for 5 minutes (second drying) to produce PDF-1, a substrate with a phase difference film.

[0182] <Examples 2-23, Comparative Examples 1-15> As shown in Tables 3-1 and 3-2 below, the same procedure as in Example 1 was performed except for changing the type of polymer preparation solution to obtain phase difference film substrates PDF-2 to PDF-38.

[0183]

[0184]

[0185] For each of the phase difference film-coated substrates PDF-1 to PDF-38, the phase difference and haze were evaluated using the following method.

[0186] [Phase Difference Evaluation] The linear phase difference, Nz coefficient, and refractive index in the N-axis direction (nz') at a wavelength of 550 nm were measured using an AxoScan from Axometrics, and the results are summarized in Tables 4-1 and 4-2. The Nz coefficient is calculated using the following formula (eq2), where nx' is the refractive index in the slow phase axis direction, ny' is the refractive index in the fast phase axis direction, nz' is the refractive index in the polar angle direction, and d represents the phase difference film thickness.

[0187] [Haze Evaluation] Using a Haze Meter HZ-V3 manufactured by Suga Test Instruments, the substrate was positioned so that the light source was perpendicular to the substrate, and the haze was measured at room temperature. The results are summarized in Tables 4-1 and 4-2.

[0188]

[0189]

[0190] Examples 1 to 23 in Tables 4-1 and 4-2 show that the single-layer phase difference material of the present invention exhibits increased phase difference values ​​and Nz coefficients compared to conventional materials (Comparative Examples 1 to 15). The decrease in refractive index (nz') in the polar angular direction indicates that the phase difference contribution in the z-axis direction is suppressed, while the phase difference contribution in the x-axis direction is increased. As described above, when used as a half-wave plate, a phase difference value of approximately 270 nm and an Nz coefficient of approximately 0.5 to 0.6 were obtained, indicating that the single-layer phase difference material of the present invention exhibits superior properties compared to conventional materials. The polymer (P) used in the single-layer phase difference material of the present invention can be highly controlled by synthesis using a polymerization control agent (A) which is a raft agent, resulting in high molecular weight distribution and uniformity of terminal functional groups. These factors contribute to the mechanism by which the above-mentioned advantages are expressed.

[0191] The single-layer phase difference material of the present invention exhibits lower haze (cloudiness) compared to conventional materials. Optical films, including phase difference films, require low haze in terms of light transmittance, and the single-layer phase difference material of the present invention can be said to have good properties. The occurrence of haze is thought to originate from the formation of polydomains due to disturbances in the orientation uniformity of the liquid crystal material within the phase difference film, and it is presumed that the single-layer phase difference material of the present invention has high orientation uniformity and is less prone to polydomain formation. As with the above, these are also thought to depend on the polymer properties.

[0192] [Reliability Evaluation] The single-layer phase difference film prepared as described above was evaluated for the rate of change of phase difference under high temperature and high humidity conditions. For high temperature, the film was left in a constant temperature oven set to 105°C for 200 hours. For high humidity, the film was left in a high humidity oven set to 65°C and 90% humidity for 200 hours. The rate of change of phase difference after these conditions is summarized in Tables 5-1 and 5-2. The rate of change of phase difference was calculated as follows: (rate of change (%)) = [(phase difference value after 200 hours) / (initial phase difference value)] × 100. Note that a smaller rate of change of phase difference after aging is better for each condition.

[0193]

[0194]

[0195] Based on the reliability evaluations in Tables 5-1 and 5-2, the single-layer phase difference materials of the present invention (Examples 24-46) exhibit a smaller phase difference fluctuation rate after aging under high temperature and high humidity conditions compared to conventional materials (Comparative Examples 16-30), demonstrating superior performance. The phase difference fluctuation after aging indicates that the orientation state of the liquid crystalline mesogen exhibiting the phase difference is changing under high temperature and high humidity conditions. This suggests that the photosensitive groups (e.g., liquid crystalline mesogen) constituting the single-layer phase difference material of the present invention maintain a stable orientation state. This is also thought to be due to the monodispersity of the molecular weight distribution obtained by synthesis using the polymerization control agent (A), which is a raft agent, and the high orientation uniformity it provides.

[0196] [Evaluation of Coatability] Using the polymers synthesized in Synthesis Examples 1 to 38, the polymer preparation solutions were re-prepared under the conditions described in Tables 6-1 and 6-2. Subsequently, a single-layer phase film was prepared using the obtained polymer preparation solution in the same manner as the preparation conditions for the single-layer phase difference material. The surface of the obtained single-layer phase difference film was visually inspected to evaluate whether or not there were any coating irregularities.

[0197]

[0198]

[0199] Tables 6-1 and 6-2 show that the single-layer phase difference materials of the present invention (Examples 47-69) exhibited less or no uneven coating (orange peel-like unevenness) compared to conventional materials (Comparative Examples 31-45). Uneven coating depends on the molecular weight of the polymer and the viscosity of the polymer preparation solution, but also on the physical properties of the polymer. The single-layer phase difference materials of the present invention are synthesized using a polymerization control agent (A) as a rafting agent, resulting in a highly uniform polymer, which is presumed to be the cause of the uneven coating.

Claims

A composition for forming a phase difference film, comprising a polymer (P) having terminal groups derived from a polymerization control agent (A) containing a structure selected from the group consisting of trithiocarbonate, dithiocarbamate, dithiobenzoate, and dithiocarbonate, The polymer (P) is a polymer having a photosensitive group (p) and a structural unit (X) derived from a monomer compound having a polymerizable unsaturated bonding group, in a composition for forming a phase difference film. 　 The phase difference film forming composition according to claim 1, wherein the polymerization control agent (A) is represented by a formula selected from the group consisting of the following formulas (a) to (e). (In formulas (a) to (e), R １ This represents one of the following equations (f-1) to (f-3). R ２ This represents the following formula (g-1) or (g-2). R ３ Each of these independently represents one of the following equations (h-1) to (h-6). R ４ (This represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms.) (In formulas (f-1) to (f-3), R ５ and R ７ Each of these independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, R ６ (* represents a single bond or an alkylene group with 1 to 6 carbon atoms. * represents a bonding site.) (In formulas (g-1) to (g-2), R ８ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyano group, a carboxy group or a carboxylic acid ester group, R ９ and R １０ each independently represent a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms or a phenyl group, R １１ represents a single bond or an alkylene group having 1 to 6 carbon atoms, R １２ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. * represents a bonding site.) (In formulas (h-1) to (h-6), R １３ R represents a single bond or an alkylene group having 1 to 6 carbon atoms. １４ R represents a single bond or an alkylene group having 1 to 6 carbon atoms. １５ R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １６ (* represents a carboxyl group or hydroxyl group. * represents a bonding site.) 　 The phase difference film forming composition according to claim 1, wherein the polymerization control agent (A) is any compound represented by the following formulas (R-1) to (R-24). (In formula (R-10), Me represents a methyl group.) A method for manufacturing a single-layer phase difference material, comprising the following steps (I) to (III). (I) : A step of applying the phase difference film forming composition according to any one of claims 1 to 3 onto a substrate to form a coating film. (II): A step of irradiating the coating film with polarized ultraviolet light. (III): A step of heating the coating film irradiated with ultraviolet light to obtain a single-layer phase difference material. 　 A single-layer phase difference material formed from a phase difference film forming composition according to any one of claims 1 to 3.

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