KR20150105629A - Photopolymerizable liquid crystal composition, optical compensation film, optical compensation laminate film, electrode substrate, substrate for liquid crystal display devices, and liquid crystal display device - Google Patents

Abstract

An optical compensatory film, an optical compensatory laminate film, an electrode substrate, and an optical compensation film using the same, which can improve the wavelength dispersion characteristics of birefringence and can form a positive A plate having a good heat resistance against the manufacturing process of a liquid crystal display device, Provided are a substrate for a liquid crystal display and a liquid crystal display. (A) for forming an optical compensation film exhibiting positive uniaxial anisotropy and having an aliphatic ring and having no aromatic ring and a second photopolymerizable liquid crystal (B) having an aromatic ring , The amount of the first photopolymerizable liquid crystal (A) is 50% by mass or more and less than 100% by mass and the amount of the second photopolymerizable liquid crystal (B) is 0% by mass or more and 50% By mass or less. The optical compensation laminated film 12 has an optical compensation film 12A showing negative uniaxial anisotropy and an optical compensation film 12B showing positive uniaxial anisotropy produced by using the above composition.

Description

TECHNICAL FIELD [0001] The present invention relates to a photopolymerizable liquid crystal composition, an optical compensatory film, an optical compensatory laminated film, an electrode substrate, a substrate for a liquid crystal display device, and a liquid crystal display device using the same. DEVICES, AND LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a photopolymerizable liquid crystal composition, and to an optical compensation film, an optical compensation laminated film, an electrode substrate, a substrate for a liquid crystal display, and a liquid crystal display using the photopolymerizable liquid crystal composition.

For the liquid crystal display device, an optical compensation film (also called a retardation film) having birefringence and controlling the phase of light is used for enlarging the viewing angle and the like. Particularly, in a liquid crystal display device of a vertical orientation (hereinafter abbreviated as " VA ") mode, the viewing angle tends to be narrow and the optical compensation film is an essential component. Patent Document 5 discloses that, in a VA mode liquid crystal display device, a positive A plate is used as retardation compensation to suppress light leakage when the viewing angle is increased.

Conventionally, the optical compensation film and the polarizing film are externally attached to the liquid crystal cell, and the thickness of the optical compensation film is about 50 to 150 mu m.

On the other hand, in recent years, thinning of a liquid crystal display device and an electronic apparatus on which the liquid crystal display device is mounted has been studied by forming an optical compensation laminated film in a liquid crystal cell.

Examples of the form of the optical compensation laminated film include the following optical compensation laminated films (i) to (iv) and the like.

(i) An optically compensated laminated film in which a biaxial plate is laminated on an alignment film such as polyimide.

(ii) An optical compensation film (hereinafter also referred to as a positive A plate) showing positive uniaxial anisotropy and an optical compensation film (hereinafter also referred to as a negative compensation film) exhibiting positive uniaxial anisotropy on the alignment film of polyimide or the like, (Also referred to as negative C plate) are sequentially laminated.

(iii) An optical compensation laminated film in which a positive A plate is laminated on a negative C plate via an orientation film.

(iv) An optically compensated laminated film in which a positive A plate is directly laminated on a negative C plate functioning as an orientation film.

Patent Documents 1 and 2 disclose a substrate for a liquid crystal display having the optical compensation laminated film (iii) or (iv).

In Examples 1 and 2 of Patent Document 1, polyester is coated on a substrate, the obtained coating film is subjected to heat drying and firing, and then subjected to rubbing treatment to form a negative C plate having a function as an alignment film have. Thereafter, a photopolymerizable liquid crystal is coated on the negative C plate, heated and dried, and photo-polymerization is performed to form a positive A plate (paragraphs 0025, 0026).

In all of Examples 1 and 2 of Patent Document 1, only one type of photopolymerizable liquid crystal having an aromatic ring is used as the photopolymerizable liquid crystal of the material for the positive A plate.

In Example 8 of Patent Document 2, polyimide is coated on a substrate, and the obtained coating film is subjected to heat drying and firing to form a negative C plate. After forming an alignment film on the negative C plate and rubbing treatment, a photopolymerizable liquid crystal is applied, dried, and photopolymerized to form a positive A plate (paragraphs 0098 to 0100).

In all of Examples 1 to 12 of Patent Document 2, only one type of photopolymerizable liquid crystal having an aromatic ring is used as the photopolymerizable liquid crystal of the material for the positive A plate.

Japanese Patent Application Laid-Open No. 2010-230823 Japanese Patent Application Laid-Open No. 2009-223304 International Publication No. 2009/148142 International Publication No. 2011/004826 Japanese Patent Application Laid-Open No. 11-258605

In the positive A plate for a color liquid crystal display device, wavelength dispersion of the retardation Re shown in the image curve I of Fig. 5 is required. However, in the conventional positive A plate, as in Patent Documents 1 and 2, conventionally, a photopolymerizable liquid crystal having an aromatic ring is used, and it is difficult to obtain the expected wavelength dispersion by the light absorption of the aromatic ring. Specifically, in a conventional positive A plate using a photo-polymerizable liquid crystal having an aromatic ring, as shown by the image curve II in FIG. 5, Re becomes smaller as the wavelength becomes longer. Re is an index of birefringence in the x-y plane, and its definition will be described later.

Therefore, in the positive A plate, the design of the retardation compensation is performed with a specific wavelength, specifically, the green light having the highest visibility. In the conventional positive A plate, the leakage of the red and blue light components could not be sufficiently reduced in the black display when the viewing angle was increased in order to show the wavelength dispersion of the image curve II in Fig.

Patent Documents 3 and 4 disclose a photopolymerizable liquid crystal having an aliphatic ring and no aromatic ring (see Claim 1 of Patent Document 3 and Claim 1 of Patent Document 4).

The above patent documents mainly focus on the use of an optical information recording and reproducing apparatus, and the application to an optical compensation film inside a liquid crystal cell is not described. However, all of the above materials exhibit a positive value? N (see Table 2 of Patent Document 3 and Table 2 of Patent Document 4), and can be used as a positive A plate material. Here,? N is refractive index anisotropy.

It is considered that the wavelength dispersion characteristics of Re can be improved in a positive A plate using a photopolymerizable liquid crystal having no aromatic ring.

In the case of forming the optical compensation film inside the liquid crystal cell, heat resistance is required for the optical film after the film formation so that the optical property of the optical compensation film does not change. However, the photo-polymerizable liquid crystal having no aromatic ring described in Patent Documents 3 and 4 is inferior in heat resistance to a photo-polymerizable liquid crystal having an aromatic ring.

An object of the present invention is to provide a photopolymerizable liquid crystal composition capable of improving the wavelength dispersion characteristics of birefringence and capable of forming a positive A plate having a good heat resistance against a manufacturing process of a liquid crystal display device.

"Improving the wavelength dispersion characteristics of birefringence" means that the wavelength dispersion characteristics of birefringence are close to ideal values for a liquid crystal display device.

An object of the present invention is to provide an optical compensation film comprising a positive A plate having improved birefringence wavelength dispersion characteristics and good heat resistance to a manufacturing process of a liquid crystal display device.

An object of the present invention is to provide an optical compensation laminated film including a negative C plate and a positive A plate, which has improved wavelength dispersion characteristics of birefringence and has good heat resistance to a manufacturing process of a liquid crystal display device.

An object of the present invention is to provide an electrode substrate, a substrate for a liquid crystal display device, and a liquid crystal display device which are excellent in optical characteristics and can be made thin and low in cost.

The present invention provides a photopolymerizable liquid crystal composition, an optical compensatory film, an optical compensatory laminated film, an electrode substrate, a substrate for a liquid crystal display, and a liquid crystal display device having the following structures [1] to [15]

The present inventors have found that the use of the first photopolymerizable liquid crystal (A) having an aliphatic ring and no aromatic ring in combination with the second photopolymerizable liquid crystal (B) having an aromatic ring improves the wavelength dispersion characteristics of birefringence, Further, it has been found that a positive A plate having a good heat resistance can be formed in the manufacturing process of a liquid crystal display device.

[1] A positive photopolymerizable liquid crystal composition for forming an optical compensation film exhibiting positive uniaxial anisotropy,

A first photopolymerizable liquid crystal (A) having an aliphatic ring and no aromatic ring,

A second photo-polymerizable liquid crystal (B) having an aromatic ring,

The amount of the first photopolymerizable liquid crystal (A) is 50% by mass or more and less than 100% by mass, the amount of the second photopolymerizable liquid crystal (B) is 0% by mass to 50% by mass % Or less.

[2] The first photopolymerizable liquid crystal (A) may be a monofunctional photopolymerizable liquid crystal containing one photopolymerizable reactive group in one molecule and / or a two-functional photopolymerizable A photopolymerizable liquid crystal composition according to [1], which contains a liquid crystal.

[3] The photopolymerizable liquid crystal composition according to [2], wherein the first photopolymerizable liquid crystal (A) contains a monofunctional photopolymerizable liquid crystal represented by the following formula (11).

^{_{CH 2 = CR 11 -COO- (L}} 1) a1 -E 11 - (S 1) b1 -E 12 - (T 1) c1 - (E 13) d1 -R 12 ··· (11)

(Wherein the symbols have the following meanings: R ¹¹ : A hydrogen atom or a methyl group. R ^{12 represents} an alkyl group having 1 to 8 carbon atoms or a fluorine atom (provided that in the case of an alkyl group, an ether-bonding oxygen atom may be bonded to the carbon-carbon bond or to the end bonded to the ring group, Or may be substituted). L ¹ may be an ether bond oxygen atom between carbon-carbon bonds, some or all of the hydrogen atoms may be substituted with fluorine atoms, and may have COO, OCO or O at a position at which they bond to E ¹¹ . An alkyl group having 1 to 8 carbon atoms. E ¹¹ , E ¹² and E ¹³ each independently represents a trans-1,4-cyclohexylene group or a trans-2,6-decahydronaphthalene group, provided that the hydrogen atom bonded to the carbon atom in the group is a fluorine atom or a methyl group ). S ¹ and T ¹ are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - or a single bond. a1, b1, c1 and d1: independently 0 or 1.)

[4] The photopolymerizable liquid crystal composition according to [2], wherein the first photopolymerizable liquid crystal (A) contains a bifunctional photopolymerizable liquid crystal represented by the following formula (12).

^{_{CH 2 = CR 21 -COO- (L}} 2) a2 -E 21 - (S 2) b2 -E 22 - (T 2) c2 - (E 23) d2 - (M 2) e2 -OCO-CR 22 = CH ₂ (12)

(Wherein R ²¹ and R ²² are each independently a hydrogen atom or a methyl group, L ² is an ether-bonding oxygen atom between carbon-carbon bonds, An alkyl group having 1 to 8 carbon atoms which may be substituted with a fluorine atom and may have COO, OCO or O at a position at which the alkylene group is bonded to E ²¹ M ² : and, even if a part or all of the hydrogen atoms are substituted with fluorine atoms and an alkyl group of E ^23, and 1 to 8 carbon atoms at a position which may have a COO, OCO or O, which combination of E ^21, E ²² and E ^23.: Each independently represents a trans-1,4-cyclohexylene group or a trans-2,6-decahydronaphthalene group (provided that the hydrogen atom bonded to the carbon atom in the group may be substituted by a fluorine atom or a methyl group) S ² and T ² are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - or a single bond, a2, b2, c2, d2 and e2 : Each independently 0 or 1.)

[5] The photopolymerizable liquid crystal composition according to any one of [1] to [4], wherein the second photopolymerizable liquid crystal (B) is represented by the following formula (20)

Q ¹ -Z ¹ -A ¹ -Z ³ -MZ ⁴ -A ² -Z ² -Q ² (20)

(Provided that the symbols in the formula represent the following meanings: Q ¹ and Q ^2:. Each independently a photo polymerization reactive group Z ^1, Z ^2, Z ³ and Z ^4:.. Each a single bond or a divalent connecting group independently A ¹ and A ² : each independently a spacer group having 2 to 20 carbon atoms M: mesogen group containing an aromatic ring)

[6] The photopolymerizable liquid crystal composition according to [5], wherein the second photopolymerizable liquid crystal (B) contains a photopolymerizable liquid crystal represented by the following formula (21).

^{_{CH 2 = CR 41 -COO- (E}} 41) m4 -Cy-Y 4 -Cy- (E 42) n4 -OCO-CR 42 = CH 2 ··· (21)

(Wherein R ⁴¹ and R ⁴² each independently represents a hydrogen atom or a methyl group, Y ^{4 is} -OCO- or -COO-, m ⁴ and n ⁴ are each independently 0 or 1 E ⁴¹ and E ⁴² each independently represent a 1,4-phenylene group or a trans-1,4-cyclohexylene group, provided that at least one of E ⁴¹ and E ⁴² is 1 , A 4-phenylene group, a cy: trans-1,4-cyclohexylene group, the 1,4-phenylene group and the trans-1,4-cyclohexylene group are groups in which the hydrogen atom in the group is fluorine atom, chlorine And may be substituted with an atom or a methyl group.)

[7] The photopolymerizable liquid crystal composition according to [5], wherein the second photopolymerizable liquid crystal (B) contains a photopolymerizable liquid crystal represented by the following formula (22).

^{_{CH 2 = CR 51 -COO- (L}} 5) k5 -E 51 -E 52 -E 53 -E 54 - (M 5) n5 -OCO-CR 52 = CH 2 ··· (22)

. (However, expression of the symbols have the following meanings: R ⁵¹ and R ^52: each independently represent a hydrogen atom or a methyl group and k5 n5: each independently 0 or _{^{1. L 5: - (CH 2}} ) p5 O- or - (CH _{2) p5} - (wherein, p5 is an integer of 2-8.) M ^5:. -O (CH _{2) p5} - or - (CH _{2) p5} - (wherein, p5 is an integer of 2-8. E ⁵¹ : 1,4-phenylene group, E ⁵² , E ⁵³ and E ⁵⁴ : each independently represents a 1,4-phenylene group or a trans-1,4-cyclohexylene group, and E ⁵² and E ⁵³ At least one of which is a trans-1,4-cyclohexylene group, wherein the 1,4-phenylene group and the trans-1,4-cyclohexylene group are groups in which the hydrogen atom bonded to the carbon atom in the group is a fluorine atom, And may be substituted with an atom or a methyl group.)

[8] The photopolymerizable liquid crystal composition according to [5], wherein the second photopolymerizable liquid crystal (B) contains a photopolymerizable liquid crystal represented by the following formula (23).

^{_{CH 2 = CR 61 -COO- (L}} 6) k6 -E 61 -E 62 -E 63 - (M 6) n6 -OCO-CR 62 = CH 2 ··· (23)

(Wherein R ⁶¹ and R ⁶² are each independently a hydrogen atom or a methyl group, k6 and n6 are each independently 0 or 1. L ⁶ : - (CH ₂ ) _p ⁶ O-, -Cy-COO- (. Cy is trans-1,4-cyclohexylene group), or -Cy-OCO- (wherein, p6 is an integer of ^{2 ~ 8.) M 6:} . -O (CH 2) p6 -, -OCO-Cy- (Cy is trans-1,4-cyclohexylene group), or -COO-Cy- wherein p6 is an integer of 2 to 8. E ⁶¹ , E ⁶² and E ⁶³ : Each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group, provided that at least one of E ⁶¹ , E ⁶² and E ⁶³ is a 1,4-phenylene group, E ⁶¹ in the case of L ⁶ is -Cy-OCO- is trans-1,4-cyclohexylene group, and L ⁶ is - (CH ₂ ) _p6 O-, or when k6 is 0, each of E ⁶¹ and E ⁶³ is a 1,4-phenylene group, and E ⁶² is a trans-1,4-cyclohexylene group. However, in the 1,4-phenylene group and the trans-1,4-cyclohexylene group, the hydrogen atom bonded to the carbon atom in the group may be substituted by a fluorine atom, a chlorine atom or a methyl group.)

[9] The photopolymerizable liquid crystal composition according to [5], wherein the second photopolymerizable liquid crystal (B) contains a photopolymerizable liquid crystal represented by the following formula (24).

^{_{CH 2 = CR 71 -COO- (L}} 7) k7 -Ph- (X 7) -Ph- (Y 7) -Ph- (M 7) n7 -OCO-CR 72 = CH 2 ··· (24)

(Wherein R ⁷¹ and R ⁷² each independently represents a hydrogen atom or a methyl group, X ⁷ and Y ⁷ each independently represent -OCO- or -COO-, L ⁷ represents - (CH _{2) p7 O-, - (CH} 2) p7 O-COO-, - (CH 2) p7 OCO- or - (CH _{2) p7} COO- (wherein, p7 is an integer of ^{2 ~ 8) M 7..} : _{-O (CH 2) p7 -,} OCO-O (CH 2) p7 -, -OCO- (CH 2) p7 or _{-COO (CH 2) p7 -.} (. wherein, p7 is an integer of 2 ~ 8) k7 And n7 independently of each other are 0 or 1. Ph: 1,4-phenylene group, provided that the 1,4-phenylene group is such that the hydrogen atom bonded to the carbon atom in the group is substituted by a fluorine atom, a chlorine atom or a methyl group do.)

[10] An optical compensation film comprising a photopolymerizable liquid crystal composition according to any one of [1] to [9], which exhibits positive uniaxial anisotropy.

[11] An optical compensating laminated film having an optical compensation film exhibiting negative uniaxial anisotropy and an optical compensation film exhibiting positive uniaxial anisotropy [10] laminated on the optical compensation film.

[12] The optical compensatory laminate film according to [11], wherein the optical compensation film exhibiting negative uniaxial anisotropy contains polyimide having an aliphatic ring in its skeleton.

[13] An electrode substrate having an optical compensation laminated film of [12] and an electrode formed on the optical compensation laminated film on a substrate.

[14] A substrate for a liquid crystal display having the electrode substrate of [13] and an alignment film formed on the electrode substrate.

[15] A liquid crystal display device having the liquid crystal substrate, the counter substrate, and the liquid crystal substrate sandwiched between the liquid crystal substrate and the counter substrate.

The photopolymerizable liquid crystal composition of the present invention can improve the wavelength dispersion characteristics of birefringence and can form a positive A plate having a good heat resistance against the manufacturing process of a liquid crystal display device.

The optical compensation film comprising the positive A plate of the present invention has improved wavelength dispersion characteristics of birefringence and has a good heat resistance against the manufacturing process of a liquid crystal display device.

The optical compensatory laminated film of the present invention includes a negative C plate and a positive A plate, and improves the wavelength dispersion characteristics of birefringence and has a good heat resistance to the manufacturing process of a liquid crystal display device.

The electrode substrate, the substrate for a liquid crystal display, and the liquid crystal display device of the present invention having the optical compensation laminated film have good optical characteristics. Since the electrode substrate, the substrate for a liquid crystal display, and the liquid crystal display device of the present invention are provided with the optical compensation laminated film in the liquid crystal cell, the thickness and cost can be reduced.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a exploded schematic sectional view of a liquid crystal display device according to an embodiment of the present invention; FIG.
2 is a cross-sectional view showing an example of a design change.
3 is a schematic cross-sectional view showing a structure of an optical compensation laminated film according to an embodiment of the present invention.
4A is a graph showing the relationship between the measured wavelength (nm) and Re of the optical compensation laminated film obtained in Example 21. Fig.
4B is a graph showing the relationship between the measured wavelength (nm) and Re of the optical compensation laminated film obtained in Example 22. Fig.
4C is a graph showing the relationship between the measured wavelength (nm) and Re of the optical compensation laminated film obtained in Example 23. Fig.
4D is a graph showing the relationship between the measured wavelength (nm) and Re of the optical compensation laminated film obtained in Example 24. Fig.
5 is an image graph showing the relationship between the abnormality in the positive A plate and the conventional wavelength (nm) and Re.

In the present specification, the group represented by the formula (x) may be simply referred to as a group (x).

In the present specification, a compound represented by the formula (y) may be simply referred to as a compound (y).

Here, the expressions (x) and (y) represent arbitrary expressions.

In this specification, the refractive index in the x direction, the y direction, and the z direction is set to be the xy plane, the film thickness direction in the z direction, and the refractive index in the x direction, the y direction, and the z direction, respectively, of the optical compensation film , nx, ny, and nz.

As the material of the optical compensation film, a photopolymerizable liquid crystal having a linear rod-like molecular structure is used. In the optical compensatory film, the rod-like molecules are in parallel with or near the long axis direction with respect to the film surface. The x-axis direction is the major axis direction of the rod-like molecules.

In the negative C plate, nx = ny > nz.

In the positive A plate, nx > ny = nz.

Retardation Rth, which is an index of the birefringence in the z direction in the negative C plate, and retardation Re, which is an index of birefringence in the x-y plane in the positive A plate, are defined by the following equations.

Rth = P x da

(Where da is the thickness of the negative C plate and P = ((nx + ny) / 2 - nz).

Re =? N x db

(Where? N is refractive index anisotropy,? N = nx-ny, and db is the thickness of the positive A plate).

Hereinafter, embodiments of the present invention will be described.

In the present specification, "%" represents mass% unless otherwise specified.

[Photopolymerizable liquid crystal composition]

The photopolymerizable liquid crystal composition of the present invention (hereinafter also referred to as composition (Y)) is a material for forming an optical compensation film (positive A plate) showing positive uniaxial anisotropy.

The composition (Y) contains a first photopolymerizable liquid crystal (A) having an aliphatic ring and no aromatic ring, and a second photopolymerizable liquid crystal (B) having an aromatic ring.

The photopolymerizable liquid crystal composition of the present invention is an optical compensation laminate (positive A plate) in which an optical compensation film (positive A plate) exhibiting positive uniaxial anisotropy is laminated on an optical compensation film (negative C plate) exhibiting negative uniaxial anisotropy which functions as an orientation film It can be preferably applied to a film.

An aromatic ring has light absorption, and its light absorption depends on wavelength. Therefore, in the conventional positive A plate using only the second photopolymerizable liquid crystal (B) having an aromatic ring, as shown in the image curve II of FIG. 5, as described above, Re becomes smaller as the wavelength becomes longer .

The wavelength dispersion of the retardation Re can be evaluated by the ratio of the green light to the retardation Re of red light, for example, when the retardation Re at any arbitrary wavelength? Is defined as Re (?). Re (450) / Re (590) < 1 in an ideal positive A plate, Re (450) / Re (590) >

By using the first photopolymerizable liquid crystal (A) having no aromatic ring, the wavelength dispersion characteristics of Re can be improved and Re (450) / Re (590) can be reduced. However, a material not having an aromatic ring tends to be inferior in heat resistance to a material having an aromatic ring. Therefore, when a positive A plate is formed using only the first photopolymerizable liquid crystal (A) having an aliphatic ring and no aromatic ring, there is a fear that good heat resistance can not be exhibited in the manufacturing process of the liquid crystal display device have. For example, in the manufacturing process of a liquid crystal display device, there is a fear that optical characteristics are changed.

Therefore, by using the first photopolymerizable liquid crystal (A) and the second photopolymerizable liquid crystal (B) in combination, it is possible to improve the wavelength dispersion characteristics of birefringence and improve the heat resistance of the positive A plate Can be formed.

Wherein the amount of the first photopolymerizable liquid crystal (A) in the composition (Y) is 50% by mass or more and less than 100% by mass and the amount of the second photopolymerizable liquid crystal (B) Is more than 0 mass% but not more than 50 mass%.

When a first photopolymerizable liquid crystal (A) is contained in an amount of 50 mass% or more and a second photopolymerizable liquid crystal (B) in an amount of 50 mass% or less, a positive A plate exhibiting favorable wavelength dispersion can be formed. When the first photopolymerizable liquid crystal (A) is contained in an amount of less than 100% by mass and the second photopolymerizable liquid crystal (B) in an amount of more than 0% by mass, a positive A plate having good heat resistance can be formed.

Preferably, in the composition (Y), the amount of the first photopolymerizable liquid crystal (A) is 50 to 90% by mass and the amount of the second photopolymerizable liquid crystal (B) And the amount is 50 to 10% by mass. More preferably, in the composition (Y), the amount of the first photopolymerizable liquid crystal (A) is 70 to 90% by mass and the amount of the second photopolymerizable liquid crystal (B) Is 30 to 10% by mass.

Re (450) / Re (590) of the positive A plate obtained by using the composition (Y) is preferably 1.07 or less, more preferably 1.05 or less.

When the positive A plate obtained by using the composition (Y) is fired at 230 캜 for 30 minutes, the change ratio of Re (590) before and after firing is preferably 5% or less.

Since the first photopolymerizable liquid crystal (A) can form a positive A plate exhibiting wavelength dispersion, the first photopolymerizable liquid crystal (A) can contain one or two or more monofunctional photopolymerizable liquid crystal and / or bifunctional photopolymerizable liquid crystal have.

The first photopolymerizable liquid crystal (A) is preferably composed of one kind or two kinds of monofunctional photopolymerizable liquid crystal and / or bifunctional photopolymerizable liquid crystal, and is preferably a monofunctional photopolymerizable liquid crystal or a bifunctional photopolymerizable liquid crystal And it is more preferable that it is made of one kind of liquid crystal.

Examples of the monofunctional photopolymerizable liquid crystal used in the first photopolymerizable liquid crystal (A) include a compound represented by the following formula (11).

^{_{CH 2 = CR 11 -COO- (L}} 1) a1 -E 11 - (S 1) b1 -E 12 - (T 1) c1 - (E 13) d1 -R 12 ··· (11)

In the photopolymerizable liquid crystal 11, R ¹¹ is preferably a hydrogen atom or a methyl group, and is preferably a hydrogen atom. When R < ¹¹ > is a hydrogen atom, the polymerization can be rapidly advanced when the composition (Y) containing the photopolymerizable liquid crystal 11 is photopolymerized. In addition, the optical characteristics of the obtained optical compensation film are less affected by the external environment such as temperature, and there is an advantage that the deviation of the retardation Re of the optical compensation film can be reduced.

In the photopolymerizable liquid crystal 11, R ¹² is an alkyl group having 1 to 8 carbon atoms or a fluorine atom. In the case of an alkyl group, R ¹² may have an ether-bonding oxygen atom at a carbon-carbon bond or at a terminal bonding with a ring group, and some or all of hydrogen atoms may be substituted with a fluorine atom.

By making R ^{12 the} above group, the melting point (T _m : crystalline phase-nematic phase phase transition point) of the composition (Y) containing the photo-polymerizable liquid crystal (11) can be lowered. R ¹² is preferably an alkyl group having 2 to 6 carbon atoms or a fluorine atom. Further, in the case where R ¹² is an alkyl group, a linear structure is preferable because the photopolymerizable liquid crystal 11 can widen the temperature range in which liquid crystallinity is exhibited.

In the photopolymerizable liquid crystal 11, L ¹ may have an ether-bonding oxygen atom between the carbon-carbon bonds, some or all of the hydrogen atoms may be substituted with a fluorine atom, and the position of bonding to E ¹¹ Is an alkyl group having 1 to 8 carbon atoms, which may have COO, OCO or O. L ¹ _{is, - (CH 2) p1 COO-} , - (CH 2) p1 OCO-, - (CH 2) p1 O- or - (CH _{2) p1} - are preferred, p1 is an integer of 1-8 desirable. L ¹ is, - (CH _{2) p1} COO- more preferably, p1 is more preferably an integer of 1-8.

Generally, when the photo-polymerizable liquid crystal is polymerized, the value of refractive index anisotropy? N tends to decrease before and after polymerization. However, when L < ¹ > is a group having the above-mentioned polymethylene group, it is possible to suppress the decrease in the value of DELTA n before and after the polymerization. From the viewpoint of ensuring liquid crystallinity before polymerization, p1 is preferably an integer of 2 to 4.

In the photopolymerizable liquid crystal (11), E ¹¹ , E ¹² and E ¹³ each independently represent a trans-1,4-cyclohexylene group or a trans-2,6-decahydronaphthalene group. In E ¹¹ , E ¹² and E ¹³ , the hydrogen atom bonded to the carbon atom in the group may be substituted with a fluorine atom or a methyl group. However, in the present invention, the trans-1,4-cyclohexylene group and the trans-2,6-decahydronaphthalene group are preferably an unsubstituted group in which the hydrogen atom bonded to the carbon atom in these groups is not substituted with another group Do.

In the photopolymerizable liquid crystal 11, S ¹ and T ¹ are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - or a single bond . From the viewpoint of the liquid crystalline expression of the compound, a single bond is preferable.

In the photopolymerizable liquid crystal 11, a1, b1, c1 and d1 are each independently 0 or 1.

The photopolymerizable liquid crystal 11 preferably has the following group (I) or group (II) in the molecule.

[Chemical Formula 1]

Specific examples of the photopolymerizable liquid crystal 11 having a group (I) include the following compound (11A). The symbols in the compound (11A) are as described above. When a structural equivalent group is present in the alkyl group in the formula, a straight chain alkyl group is preferred, including all of the groups.

(2)

In the compound (11A), R ¹¹ is a hydrogen atom is preferred and, a1 is 0 or 1 are preferred, R ¹² is preferably straight-chain alkyl group or fluorine atom with a carbon number of 2-6. L ¹ is, - (CH _{2) p1} COO- or - a (CH _{2) p1} OCO-, is preferable because it can secure a wider liquid crystal. Further, L < ¹ _> is particularly preferable because - (CH ₂ ) _p1 COO- is less in the number of synthesis steps. Furthermore, p1 is particularly preferably an integer of 2 to 4.

Examples of the compound (11A) include the following compounds. The sign of these compounds is as described above. p1 is preferably an integer of 2 to 4. The trans-2,6-decahydronaphthalene group is preferably a trans-2,6-trans decahydronaphthalene group in that it exhibits liquid crystallinity. R ¹² is preferably a linear alkyl group having 2 to 6 carbon atoms.

(3)

For a method of synthesizing the above compounds (11A-1) and (11A-2), see paragraph 0050-0056 of Patent Document 3.

Specific examples of the photopolymerizable liquid crystal 11 having a group (II) include the following compounds (11B) to (11D). The sign in the compound is as described above. When a structural equivalent group is present in the alkyl group in the formula, a straight chain alkyl group is preferred, including all of the groups.

[Chemical Formula 4]

In the compounds (11B) to (11D), R ¹¹ is a hydrogen atom, a 1 is 0 or 1, and R ¹² is preferably a linear alkyl group having 2 to 6 carbon atoms or a fluorine atom. L ¹ is - (CH _{2) p1} COO- or - a (CH _{2) p1} OCO-, it is preferable because it can secure a wider liquid crystal. Here, p1 is particularly preferably an integer of 2 to 4.

Examples of the compounds (11B) to (11D) include the following compounds. The sign of these compounds is as described above. p1 is preferably an integer of 2 to 4. R ¹² is preferably a linear alkyl group having 2 to 6 carbon atoms. When a structural equivalent group is present in the alkyl group in the formula, a straight chain alkyl group is preferred, including all of the groups.

[Chemical Formula 5]

The compounds (11B) to (11D) can be produced by applying a known synthesis method in the same manner as the compound (11A).

Examples of the bifunctional photopolymerizable liquid crystal used in the first photopolymerizable liquid crystal (A) include compounds represented by the following formula (12).

^{_{CH 2 = CR 21 -COO- (L}} 2) a2 -E 21 - (S 2) b2 -E 22 - (T 2) c2 - (E 23) d2 - (M 2) e2 -OCO-CR 22 = CH ₂ (12)

In the photopolymerizable liquid crystal 12, R ²¹ and R ²² are each independently a hydrogen atom or a methyl group, preferably a hydrogen atom. When R ²¹ and R ²² are hydrogen atoms, the polymerization can proceed rapidly when the composition (Y) containing the photopolymerizable liquid crystal 12 is photo-polymerized. Further, the optical characteristics of the obtained optical compensation film are less affected by the external environment such as temperature, and the deviation of the retardation Re of the optical compensation film is advantageously reduced.

In the optical polymerizable liquid crystal (12), L ² is a carbon - and may have an ether-bonding oxygen atom sex between carbon bond, and optionally a part or all of the hydrogen atoms are substituted with fluorine atoms, the position of engagement with E ²¹ Is an alkyl group having 1 to 8 carbon atoms which may have COO, OCO or O. L ² _{is, - (CH 2) p2 COO-} , - (CH 2) p2 OCO-, - (CH 2) p2 O- or - (CH _{2) p2} - are preferred, p2 is an integer of 1-8 desirable. L ² is, in terms of the liquid crystalline compound expressed in the - (CH _{2) p2} COO- is more preferable, p2 is more preferably an integer of 1-8.

In the optical polymerizable liquid crystal (12), M ² is carbon - and may have an ether bond oxygen atom sex between carbon bond, and optionally a part or all of the hydrogen atoms are substituted with fluorine atoms, the position of engagement with E ²³ Is an alkyl group having 1 to 8 carbon atoms which may have COO, OCO or O. M ² is preferably -OCO (CH ₂ ) _{q 2} -, -COO (CH ₂ ) _{q 2} -, -O (CH ₂ ) _{q 2} - or - (CH ₂ ) _{q 2} -, and q 2 is an integer of 1 to 8 desirable. M ² is more preferably -OCO (CH ₂ ) _{q 2} - or - (CH ₂ ) _{q 2} -, _{q 2} is more preferably an integer of 1 to 8, and -OCO (CH ₂ ) _q2 - is particularly preferable, and q2 is particularly preferably an integer of 1 to 8.

Generally, when the photo-polymerizable liquid crystal is polymerized, the value of refractive index anisotropy? N tends to decrease before and after polymerization. However, L ² and M ^2, in the case of the group having a polymethylene, it is possible to suppress a decrease in the Δn value of the before and after the polymerization. Furthermore, p2 and q2 are each independently preferably an integer of 2 to 4 in terms of securing liquid crystallinity before polymerization.

In the optical polymerizable liquid crystal ^{(12), E 21, E} 22 and E ²³ are, each independently, a trans-1,4-cyclohexyl is a xylene group or trans-2,6-decahydronaphthalene group. E ²¹ , E ²² and E ²³ may be such that a hydrogen atom bonded to a carbon atom in the group is substituted with a fluorine atom or a methyl group. However, in the present invention, the trans-1,4-cyclohexylene group and the trans-2,6-decahydronaphthalene group are preferably an unsubstituted group in which the hydrogen atom bonded to the carbon atom in these groups is not substituted with another group Do.

In the photo-polymerizable liquid crystal 12, S ² and T ² are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - to be. From the viewpoint of the liquid crystalline expression of the compound, a single bond is preferable.

In the photopolymerizable liquid crystal 12, a2, b2, c2, d2 and e2 are each independently 0 or 1.

The photo-polymerizable liquid crystal 12 preferably has the following group (I) or group (II) in the molecule.

[Chemical Formula 6]

Specific examples of the photopolymerizable liquid crystal 12 having a group (I) include the following compound (12A). The symbols in the compound (12A) are as described above. When a structural equivalent group is present in the alkyl group in the formula, a straight chain alkyl group is preferred, including all of the groups.

(7)

In the compound (12A), R ²¹ and R ²² are preferably hydrogen atoms, and a 2 and e 2 are each independently 0 or 1. From the viewpoint of securing liquid crystallinity, p2 and q2 are each independently preferably an integer of 2 to 4.

Examples of the compound (12A) include the following compounds. The sign of these compounds is as described above. p2 and q2 are each independently preferably an integer of 2 to 4. The trans-2,6-decahydronaphthalene group is preferably a trans-2,6-trans decahydronaphthalene group in that it exhibits liquid crystallinity.

[Chemical Formula 8]

For the synthesis method of the compounds (12A-1) and (12A-2), see paragraph 0055-0057 of Patent Document 4.

Specific examples of the photopolymerizable liquid crystal 12 having a group (II) include the following compound (12B). The symbols in the compound (12B) are as described above. When a structural equivalent group is present in the alkyl group in the formula, a straight chain alkyl group is preferred, including all of the groups.

[Chemical Formula 9]

In the compound (12B), R ²¹ and R ²² is a hydrogen atom, a2, and e2 are preferably each independently 0 or 1; From the viewpoint of securing liquid crystallinity, p2 and q2 are each independently preferably an integer of 2 to 4.

Examples of the compound (12B) include the following compounds. The sign of these compounds is as described above. p2 and q2 are each independently an integer of 2 to 4.

[Chemical formula 10]

Similar to the compound (12A), the compound (12B) can also be produced by applying a known synthesis method.

The second photo-polymerizable liquid crystal (B) may contain one or more monofunctional photo-polymerizable liquid crystals and / or bifunctional photo-polymerizable liquid crystals. The second photopolymerizable liquid crystal (B) preferably contains one or two or more bifunctional photopolymerizable liquid crystals from the viewpoint of improvement in heat resistance.

As the second photo-polymerizable liquid crystal (B), a compound represented by the following formula (20) is preferable.

Q ¹ -Z ¹ -A ¹ -Z ³ -MZ ⁴ -A ² -Z ² -Q ² (20)

The symbols in the formulas have the following meanings.

Q ¹ and Q ² are each independently a photopolymerizable reactive group.

Z ¹ , Z ² , Z ³ and Z ⁴ are each independently a single bond or a divalent linking group.

A ¹ and A ² each independently represent a spacer group having 2 to 20 carbon atoms.

M is a mesogen group containing an aromatic ring.

As the second photo-polymerizable liquid crystal (B), compounds represented by the following formulas (21), (22), (23) or (24) are preferable.

^{_{CH 2 = CR 41 -COO- (E}} 41) m4 -Cy-Y 4 -Cy- (E 42) n4 -OCO-CR 42 = CH 2 ··· (21)

In the photopolymerizable liquid crystal 21, R ⁴¹ and R ⁴² are each independently a hydrogen atom or a methyl group, and preferably a hydrogen atom. When R ⁴¹ and R ⁴² are hydrogen atoms, the polymerization can proceed rapidly when the composition (Y) containing the photopolymerizable liquid crystal (21) is photo-polymerized. In addition, the optical properties of the resulting optical compensation film are less affected by the external environment such as temperature, and there is an advantage that the deviation of the retardation Re is reduced within the plane of the optical compensation film.

Y ⁴ is -OCO- or -COO-. -OCO- is preferable in that the melting point ( _Tm ) can be lowered, and -COO- is preferable in the point that a large Δn can be exhibited when the film is made into an optical compensation film.

m4 and n4 are each independently 0 or 1, and at least one of them is 1;

E ⁴¹ and E ⁴² each independently represent a 1,4-phenylene group (Ph) or a trans-1,4-cyclohexylene group (Cy). Provided that at least one of E ⁴¹ and E ⁴² is a 1,4-phenylene group.

The 1,4-phenylene group (Ph) and the trans-1,4-cyclohexylene group (Cy) may be substituted with a hydrogen atom, a fluorine atom, a chlorine atom or a methyl group in the group.

^{_{CH 2 = CR 51 -COO- (L}} 5) k5 -E 51 -E 52 -E 53 -E 54 - (M 5) n5 -OCO-CR 52 = CH 2 ··· (22)

In the photo-polymerizable liquid crystal 22, R ⁵¹ and R ⁵² are each independently a hydrogen atom or a methyl group, and preferably a hydrogen atom.

k5 and n5 are each independently 0 or 1, preferably 1.

L ^{5 is} - (CH ₂ ) _p ⁵ O- or - (CH ₂ ) _p5 - (wherein p5 is an integer of 2 to 8).

_{^{M 5: -O (CH 2)}} p5 - or - (CH _{2) p5} - (wherein, p5 is an integer of 2-8.).

Generally, when the polymerizing light polymerizable liquid crystal, in the case, but tends to the value of Δn decreases before and after the polymerization, L ⁵ and M ⁵ is a group having the above polymethylene is, the Δn value of the before and after the polymerization Can be suppressed.

E ⁵¹ is preferably a 1,4-phenylene group (Ph).

E ⁵² , E ⁵³ and E ⁵⁴ each independently represent a 1,4-phenylene group (Ph) or a trans-1,4-cyclohexylene group (Cy), and at least one of E ⁵² and E ⁵³ is trans- , And a 4-cyclohexylene group (Cy).

In the above-mentioned 1,4-phenylene group (Ph) and trans-1,4-cyclohexylene group (Cy), the hydrogen atom bonded to the carbon atom in the group may be substituted with a fluorine atom, a chlorine atom or a methyl group.

^{_{CH 2 = CR 61 -COO- (L}} 6) k6 -E 61 -E 62 -E 63 - (M 6) n6 -OCO-CR 62 = CH 2 ··· (23)

In the photopolymerizable liquid crystal 23, R ⁶¹ and R ⁶² are each independently a hydrogen atom or a methyl group, and preferably a hydrogen atom.

k6 and n6 are each independently 0 or 1, and 1 is preferred.

_{^{L 6: - (CH 2)}} p6 O-, -Cy-COO- (. Cy is trans-1,4-cyclohexylene group), or -Cy-OCO- (wherein, p6 is an integer of 2-8. ).

_{^{M 6: -O (CH 2)}} p6 -, -OCO-Cy- (. Cy is trans-1,4-cyclohexylene group), or -COO-Cy- (here, p6 is an integer of 2-8. ).

E ⁶¹ , E ⁶² and E ⁶³ each independently represent a 1,4-phenylene group or a trans-1,4-cyclohexylene group. Provided that at least one of E ⁶¹ , E ⁶² and E ⁶³ is a 1,4-phenylene group and at least one is a trans-1,4-cyclohexylene group. Also, L ⁶ is E ⁶¹ in the case of trans-1,4-cyclohexyl is -Cy-OCO-, and xylene group, L ⁶ is - (CH ₂₎ and E ⁶¹ in the case where the _p6 or O- or k6 is 0, Each of E ⁶³ is a 1,4-phenylene group, and E ⁶² is a trans-1,4-cyclohexylene group.

In the above-mentioned 1,4-phenylene group (Ph) and trans-1,4-cyclohexylene group (Cy), the hydrogen atom bonded to the carbon atom in the group may be substituted with a fluorine atom, a chlorine atom or a methyl group.

^{_{CH 2 = CR 71 -COO- (L}} 7) k7 -Ph- (X 7) -Ph- (Y 7) -Ph- (M 7) n7 -OCO-CR 72 = CH 2 ··· (24)

In the photopolymerizable liquid crystal 24, R ⁷¹ and R ⁷² are each independently a hydrogen atom or a methyl group, and a hydrogen atom is preferable.

X ⁷ and Y ⁷ are each independently -OCO- or -COO-.

L ^{7 is} - (CH ₂ ) _p ⁷ O-, - (CH ₂ ) _{p 7} O-COO-, - (CH ₂ ) _{p 7} OCO- or - (CH ₂ ) _{p 7} COO- wherein p7 is an integer of 2 to 8 .).

_{^{M 7: -O (CH 2)}} p7 -, OCO-O (CH 2) p7 -, -OCO- (CH 2) p7 or -COO (CH _{2) p7} - (here, p7 is an integer of 2-8. ).

k7 and n7 are each independently 0 or 1;

Ph is a 1,4-phenylene group.

In the 1,4-phenylene group, the hydrogen atom bonded to the carbon atom in the group may be substituted with a fluorine atom, a chlorine atom or a methyl group.

The composition (Y) may contain known photo-polymerization initiators (C), known surfactants (D), known solvents (E), and other known photopolymerization initiators in addition to the first photopolymerizable liquid crystal (A) Or other optional ingredients.

Examples of the photopolymerization initiator (C) include oxime esters, acetophenones, benzophenones, acylphosphine oxides, benzoins, benzyls, Michler's ketones, benzoin alkyl ethers and benzyl dimethyl ketal have. These may be used alone or in combination of two or more.

Examples of oxime esters include 1,2-octanedione, 1- [4- (phenylthio) -, 2- (ortho-benzoyloxime)] and ethanone, 1- [ Benzoyl) -9H-carbazol-3-yl] -, 1- (ortho-acetyloxime).

Examples of the acetophenones include 2,2-dimethoxy-1,2-diphenylethane-1-one, 1 -hydroxy-cyclohexyl-phenyl-ketone, 2- Methyl-1-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone, 2-methyl-1- (4-methoxy-phenyl) -2-methyl-propan- -Methylthiophenyl) -2-morpholinopropane-1-one and 2-hydroxy-1- {4- [4- (2- 2-methyl-propan-1-one and the like.

Examples of acylphosphine oxides include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and bis (2,4,6-trimethylbenzoyl) -diphenyl-phosphine oxide.

Examples of the surfactant (D) include the following surfactants such as anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric surfactants.

Anionic surfactants such as sodium lauryl sulfate, ammonium lauryl sulfate, triethanolamine lauryl sulfate, polyoxyethylene alkyl ether sulfates, alkyl ether phosphates, sodium oleylsuccinate, potassium myristate, potassium cocoyl fatty acid and sodium lauro Sun sarcosinate and others.

Nonionic surfactants such as polyethylene glycol monolaurate, stearic oxygen lignite, myristyl glyceryl, dioleate glyceryl, sorbitan stearate and sorbitan oleate.

Cationic surfactants such as stearyltrimethylammonium chloride, behenyltrimethylammonium chloride, stearyldimethylbenzylammonium chloride and cetyltrimethylammonium chloride.

Amphoteric surfactants, alkyl betaines such as lauryl betaine, alkylsulfobetaine, cocamidopropyl betaine and alkyldimethylaminoacetic acid betaine, alkylimidazoline, sodium lauroyl sarcosinate, sodium coco anoacetate and the like .

Any of these surfactants may be used alone, or two or more of them may be used in combination.

Examples of the solvent (E) include aliphatic hydrocarbons such as cyclohexanone, ethyl cellosolve acetate, butyl cellosolve acetate, 1-methoxy-2-propyl acetate, diethylene glycol dimethyl ether, ethylbenzene, ethylene glycol diethyl ether, Ethyl cellosolve, methyl-n-amyl ketone, propylene glycol monomethyl ether, toluene, methyl ethyl ketone, ethyl acetate, methanol, ethanol, isopropyl alcohol, butanol and isobutyl ketone.

Any of these solvents may be used alone, or two or more solvents may be used in combination.

Other optional components include antioxidants, ultraviolet absorbers, silane coupling agents, and light stabilizers.

The total amount of the first photopolymerizable liquid crystal (A) and the second photopolymerizable liquid crystal (B) in the composition (Y) is 80 mass% when the total amount of the solvent (E) other than the solvent (E) is 100 mass% Or more and less than 100 mass%, and particularly preferably 90 mass% or less and less than 100 mass%.

[Optical compensation film]

The optical compensation film of the present invention is an optical compensation film (positive A plate) exhibiting positive uniaxial anisotropy, obtained by photo-curing a coating film of the photopolymerizable liquid crystal composition of the present invention.

Re (450) / Re (590) of the positive A plate of the present invention is preferably 1.07 or less, more preferably 1.05 or less.

When the positive A plate of the present invention is fired at 230 캜 for 30 minutes, the change rate of Re (590) before and after firing is preferably 5% or less.

[Optical compensation laminated film]

The optical compensation laminated film of the present invention is obtained by laminating an optical compensation film (negative C plate) exhibiting negative uniaxial anisotropy and an optical compensation film (positive A plate) exhibiting positive uniaxial anisotropy according to the present invention.

In the optical compensation laminated film of the present invention, the order of lamination of the optical compensation film is not limited. An alignment film may be formed between the negative C plate and the positive A plate. That is, the optical compensation film of the present invention can form the optical compensation laminated film in any of the above-mentioned (i) to (iv). Among them, from the viewpoint of thinning of the optical compensation laminated film, (iv), that is, the form in which the positive A plate is laminated directly on the negative C plate having the orientation is preferable.

(PI) or its precursor polyamic acid (PAA) is preferably used as the composition of the negative C plate forming material (hereinafter sometimes referred to as the composition (X)). It is preferable that the composition (X) contains polyamic acid (PAA) in that the birefringence in the thickness direction is expressed at the time of heat imidization.

Here, the polyimide film basically has orientation. Therefore, preferably, among the polyimide (PI) or polyamic acid (PAA) for forming an alignment film of a liquid crystal display device, a material which becomes a negative C plate, that is, a material exhibiting birefringence in the thickness direction is selected.

All polyimides have good heat resistance. Therefore, when polyimide is used as the negative C plate, the optical compensation film is preferable because heat resistance is good.

Polyimides are obtained by polymerization of acid anhydrides with diamines. From the viewpoint of improving the light transmittance of the polyimide, it is preferable to have an aliphatic ring in the skeleton. In this case, an acid anhydride or diamine having an aliphatic ring in the skeleton may be selected.

When the acid anhydride has an aliphatic ring, examples of the acid anhydride include 1,2,3,4-butanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid 2 Anhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexanetetracarboxylic acid dianhydride, and the diamines include 2,2'-bis (trifluoromethyl) benzidine and p-phenylenediamine. have.

When the diamine has an aliphatic ring, examples of the acid anhydride include 3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride, 2,3,3', 4'-biphenyltetracarboxylic dianhydride and 1,2,5,6-naphthalenetetracarboxylic acid dianhydride, and the like. Examples of the diamine include trans-1,4-diaminocyclohexane, cis-1,4-diaminocyclohexane and 4,4'- Diamino-1,1'-bicyclohexane, and the like.

The composition (X) may contain one or more known solvents or one or more other optional ingredients.

The content of polyimide (PI) or polyamic acid (PAA) is preferably 10 to 30% by mass with respect to the whole composition (X).

The forming process of the negative C plate having the orientation can be performed, for example,

(S1) of forming a first coating film by coating a composition (X) containing a polyamic acid (PAA) and a solvent on a substrate by a spin coating method or the like,

(S2) of removing the solvent in the first coating film by heat drying (prebaking) at about 150 deg. C, drying under reduced pressure, or drying under reduced pressure,

A step (S3) of firing (post-baking) the polyamic acid in the coating film at about 230 DEG C to form a polyimide film,

And a step (S4) of rubbing the polyimide film.

The process of forming the positive A plate is, for example,

The above-mentioned photopolymerizable liquid crystal composition (Y) containing the first photopolymerizable liquid crystal (A) and the second photopolymerizable liquid crystal (B) was coated on the negative C plate to form a second coating film (S5),

(S6) of removing the solvent in the second coating film by heating and drying (prebaking) at about 80 deg. C, drying under reduced pressure, or drying under reduced pressure,

And a step (S7) of photo-polymerizing the photopolymerizable liquid crystals (A) and (B) by irradiating the second coating film with light such as ultraviolet light (UV).

Unreacted photopolymerizable liquid crystals (A) and (B) may be left alone by light irradiation. In this case, after the step (S7), a step (S8) of baking at about 230 deg.

The optical compensation laminated film of the present invention is preferable for a liquid crystal display device of a vertically aligned (VA) mode.

In the optical compensation laminated film, the retardation Rth, which is an index of birefringence in the z direction, is preferably 100 to 500 nm, and particularly preferably 200 to 300 nm.

In the optical compensation laminated film, retardation Re, which is an index of birefringence in the x-y plane, is preferably more than 0 nm and not more than 100 nm, particularly preferably 40 to 60 nm.

Since the optical compensation laminated film of the present invention makes the base film unnecessary, it is possible to reduce the thickness of the liquid crystal display device.

Particularly, in an optical compensation laminated film comprising a negative C plate having an orientation and a positive A plate directly stacked thereon, an orientation film is not required in the optical compensation laminated film, and further thinning can be achieved. In addition, if the number of films is small, the number of manufacturing steps can be reduced, and the manufacturing cost can be reduced.

In the present invention, the thickness da and db of the negative C plate and the positive A plate are all preferably 10 m or less, more preferably 5 m or less. Therefore, the thickness d of the optical compensation laminated film can be 20 m or less, and can be 10 m or less.

In the optical compensation laminated film of the present invention, the average transmittance at a wavelength of 400 nm to 800 nm is preferably 80% or more, and more preferably 85% or more. In the present specification, the "average transmittance" is a value measured in accordance with JIS K 7361-1.

The optical compensatory laminated film of the present invention has improved wavelength dispersion characteristics of Re, and has good optical characteristics. In addition, the optical characteristics have good heat resistance to the manufacturing process of the liquid crystal display device.

[Liquid crystal display device]

A liquid crystal display device according to an embodiment of the present invention is a color transmissive TFT liquid crystal display device in VA mode.

The present embodiment is also applicable to other active matrix type or passive matrix type liquid crystal display devices such as a monochrome liquid crystal display device, a reflection type or transflective liquid crystal display device, and a TFD liquid crystal display device.

As shown in Fig. 1, the liquid crystal display device 1 of the present embodiment includes a liquid crystal cell 1A, polarizers 51 and 52 mounted on the liquid crystal cell 1A, and a backlight BL.

The liquid crystal cell 1 includes a color filter substrate 10, a TFT substrate 20 as a counter substrate, and a liquid crystal layer 30 sandwiched between the pair of substrates.

A color filter substrate (electrode substrate, substrate for a liquid crystal display device) 10 includes a transparent substrate 11, a black matrix layer BM sequentially stacked on the liquid crystal layer 30 side, a color filter layer CF, A compensation laminated film 12, a common electrode 13, and an alignment film 14. [

The TFT substrate 20 includes a pixel electrode substrate 21 on which a plurality of pixel electrodes and a plurality of TFTs (thin film transistors), which are switching elements of the pixel electrodes, are formed in a matrix on the liquid crystal layer 30 side of the transparent substrate, And an alignment film 22 formed on the liquid crystal layer 30 side.

As the translucent substrate used for the color filter substrate 10 and the TFT substrate 20, a glass substrate is preferable.

In the transmissive liquid crystal display device 1, a transparent conductive material such as ITO (indium tin oxide) is used as the material of the common electrode 13 and the pixel electrode.

The black matrix layer (BM) is a light-shielding layer that shields adjacent dots from each other.

The color filter layer CF includes, for example, a colored layer of red (R), green (G) and blue (B). In this case, three pixel electrodes and three colored layers are formed in one pixel (one pixel = three dots).

The optical compensation laminated film 12 is the above-described optical compensation laminated film of the present invention and is preferably a laminated film of a negative C plate 12A and a positive A plate 12B as shown in Fig.

In this embodiment, the common electrode 13 is formed directly on the optical compensation laminated film 12, and the alignment film 14 is formed thereon.

The lamination structure of the color filter substrate 10 can be suitably changed in design.

For example, as shown in the color filter substrate 40, the liquid crystal cell 2A and the liquid crystal display 2 of the design change shown in Fig. 2, the optical compensation laminated film 12 is formed on the transparent substrate 11, , The black matrix layer (BM), the color filter layer (CF), the common electrode (13), and the alignment film (14).

The color filter substrate (electrode substrate, substrate for liquid crystal display device) 10 and liquid crystal display device 1 of this embodiment have good optical characteristics and heat resistance. Since the color filter substrate 10 and the liquid crystal display device 1 of the present embodiment are provided with the optical compensation laminated film 12 in the liquid crystal cell 1A, it is possible to reduce the thickness and cost.

Example

Hereinafter, the present invention will be described on the basis of examples, but the present invention is not limited thereto. Examples 11 and 12 and Examples 21 and 22 are Examples, and Examples 13 and 14 and Examples 23 and 24 are Comparative Examples.

As the photopolymerizable liquid crystal for the positive A plate, the following compounds (A1), (A2) and (B1) were prepared.

(11)

Other materials of the positive A plate are as follows.

Photopolymerization initiator (C1): " Irgacure 907 "

Surfactant (D1): Surfron S420, a fluorine-based nonionic surfactant manufactured by AGC Seiyam Chemical Co., Ltd.

Solvent (E1): Cyclopentanone.

[Example 11: Preparation of coating liquid (Y1) for positive A plate]

0.75 g of the photo-polymerizable liquid crystal (A1) and 0.25 g of the photo-polymerizable liquid crystal (B1) were mixed to obtain a liquid crystal composition. To the composition, 5% by mass of the photopolymerization initiator (C1) and 1% by mass of the surfactant (D1) were weighed and mixed, respectively. Thereafter, the solvent (E1) was added and mixed to obtain a 15 mass% solution. This was filtered with a filter having an opening diameter of 0.5 mu m to obtain a coating liquid (Y1).

The composition of the mixture is shown in Table 1.

[Example 12: Preparation of coating liquid (Y2) for positive A plate]

A coating liquid (Y2) was obtained in the same manner as in Example 11 except that the mixing composition was changed to that shown in Table 1.

[Examples 13 and 14: Preparation of coating liquids (Z1) and (Z2) for positive A plate]

The coating liquids (Z1) and (Z2) were obtained in the same manner as in Example 11, except that the mixing compositions were shown in Table 1.

[Example 21: Fabrication of optically compensated laminated film]

<Formation of Negative C plate (NC1)> [

1.14 g of trans-1,4-diaminocyclohexane was dissolved in 17.44 g of N-methyl-2-pyrrolidone, and 2.83 g of 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and N -Methyl-2-pyrrolidone was added, and the mixture was stirred at 60 占 폚 for 3 hours. Further, 0.12 g of phthalic anhydride was added, followed by stirring at 60 DEG C for 3 hours to obtain a solution of polyamic acid (PAA1). This was filtered through a filter having an opening diameter of 0.5 mu m to obtain a coating liquid (X1). The coating liquid was coated on a glass substrate by a spin coater (3000 rpm, 30 sec) and dried on a hot plate at 90 캜 for 2 minutes. After heating at 230 占 폚 for 30 minutes, rubbing treatment was performed to form a negative C plate (NC1) having the function of an alignment film. The film thickness was 3.1 mu m, the birefringence P at 590 nm in the thickness direction was 0.090, and Rth was 279 nm.

<Formation of Positive A Plate PA1>

The coating liquid (Y1) was coated on the negative C plate (NC1) with a spin coater and dried at 80 DEG C for 2 minutes to align the alignment. Thereafter, ultraviolet rays were irradiated for 60 seconds in a direction perpendicular to the substrate surface, and the coating film was cured to form a positive A plate PA1. The illuminance of the high-pressure mercury lamp used for photo-curing was 190 mW / cm 2 at a wavelength of 365 nm.

Thus, an optical compensation laminated film was obtained.

Table 1 shows the main production conditions.

[Example 22: Fabrication of optically compensated laminated film]

In the same manner as in Example 21, a negative C plate NC1 was formed.

A positive A plate PA2 was formed on the negative C plate NC1 in the same manner as in Example 21 except that the coating liquid Y2 was used instead of the coating liquid Y1 to obtain an optical compensation laminated film.

Table 1 shows the main production conditions of each example.

[Example 23, 24: Fabrication of optically compensated laminated film]

In the same manner as in Example 21, a negative C plate NC1 was formed.

Positive A plates PA3 and PA4 were formed on the negative C plate NC1 in the same manner as in Example 21 except that the coating liquids Z1 and Z2 were used instead of the coating liquid Y1 Thus, an optical compensation laminated film was obtained.

Table 1 shows the main production conditions of each example.

[evaluation]

(Measurement of Re)

The obtained optical compensation laminated film was measured for Re when the wavelength was changed in the visible light region (400 to 800 nm). From the obtained data, the value of Re (450) / Re (590) was obtained.

(Heat resistance)

The optical compensation laminated film thus obtained was fired at 230 DEG C for 30 minutes to determine the rate of change of Re (590) before and after firing. Based on the following criteria.

(○): 0 to 5%, Δ: 5 to 10%, and not (×): 10% or more.

[result]

Figs. 4A to 4D show measurement graphs of Re against wavelength in the optical compensation laminated films of Examples 21 to 24. Fig.

The evaluation results of Re (450) / Re (590) and heat resistance are shown in Table 1.

In the optical compensation laminated film of Example 23 using only the second photopolymerizable liquid crystal (B) having an aromatic ring as the photopolymerizable liquid crystal of the positive A plate material, the Re reduction level with respect to the increase of the wavelength is large, / Re (590) was 1.10.

In the optical compensation laminated film of Example 24 using only the first photopolymerizable liquid crystal (A) having no aromatic ring as the photopolymerizable liquid crystal of the positive A plate material, the decrease of Re with respect to the increase of the wavelength was suppressed, ) / Re (590) was 1.02. However, the rate of change of Re (590) before and after firing at 230 占 폚 was 5 to 10%, and the heat resistance was insufficient.

Examples 21 and 22 in which the first photopolymerizable liquid crystal (A) having no aromatic ring and the second photopolymerizable liquid crystal (B) having an aromatic ring were used as the photopolymerizable liquid crystal of the positive A plate material, , The reduction of Re with respect to the increase of the wavelength was suppressed, and Re (450) / Re (590) was 1.04. Also, the rate of change of Re (590) before and after firing at 230 DEG C was within 5%, and the heat resistance was good.

Also, the entire contents of the specification, claims, drawings and summary of Japanese Patent Application No. 2013-002538 filed on January 10, 2013 are incorporated herein by reference and are hereby incorporated by reference.

1, 2: Liquid crystal display
1A, 2A: liquid crystal cell
10, 40: Color filter substrate (electrode substrate, substrate for liquid crystal display device)
11: Transparent substrate
12: Optical compensation laminated film
12A: Negative C plate (optical compensation film showing negative uniaxial anisotropy)
12B: Positive A plate (optical compensation film showing positive uniaxial anisotropy)
13: common electrode
14:
20: TFT substrate
21: pixel electrode substrate
22: Orientation film
30: liquid crystal layer
51, 52: Polarizer
BM: Black Matrix
CF: color filter
BL: Backlight

Claims (15)

1. A photopolymerizable liquid crystal composition for forming an optical compensation film exhibiting positive uniaxial anisotropy,
A first photopolymerizable liquid crystal (A) having an aliphatic ring and no aromatic ring,
A second photo-polymerizable liquid crystal (B) having an aromatic ring,
The amount of the first photopolymerizable liquid crystal (A) is 50% by mass or more and less than 100% by mass, the amount of the second photopolymerizable liquid crystal (B) is 0% by mass to 50% by mass % Or less. The method according to claim 1,
The first photopolymerizable liquid crystal (A) may be a monofunctional photopolymerizable liquid crystal containing one photopolymerizable reactive group in one molecule and / or a two-stage functional photopolymerizable liquid crystal containing two photopolymerizable reactive groups in one molecule By weight. 3. The method of claim 2,
The first photopolymerizable liquid crystal (A) comprises a monofunctional photopolymerizable liquid crystal represented by the following formula (11).
^{_{CH 2 = CR 11 -COO- (L}} 1) a1 -E 11 - (S 1) b1 -E 12 - (T 1) c1 - (E 13) d1 -R 12 ··· (11)
(Wherein the symbols in the formulas have the following meanings.
R ¹¹ : A hydrogen atom or a methyl group.
R ^{12 represents} an alkyl group having 1 to 8 carbon atoms or a fluorine atom (provided that in the case of an alkyl group, an ether-bonding oxygen atom may be bonded to the carbon-carbon bond or to the end bonded to the ring group, Or may be substituted).
L ¹ may be an ether bond oxygen atom between carbon-carbon bonds, some or all of the hydrogen atoms may be substituted with fluorine atoms, and may have COO, OCO or O at a position at which they bond to E ¹¹ . An alkyl group having 1 to 8 carbon atoms.
E ¹¹ , E ¹² and E ¹³ each independently represents a trans-1,4-cyclohexylene group or a trans-2,6-decahydronaphthalene group, provided that the hydrogen atom bonded to the carbon atom in the group is a fluorine atom or a methyl group ).
S ¹ and T ¹ are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - or a single bond.
a1, b1, c1 and d1: independently 0 or 1.) 3. The method of claim 2,
The first photopolymerizable liquid crystal (A) is a photopolymerizable liquid crystal composition containing a bifunctional photopolymerizable liquid crystal represented by the following formula (12).
^{_{CH 2 = CR 21 -COO- (L}} 2) a2 -E 21 - (S 2) b2 -E 22 - (T 2) c2 - (E 23) d2 - (M 2) e2 -OCO-CR 22 = CH ₂ (12)
(Wherein the symbols in the formulas have the following meanings.
R ²¹ and R ²² each independently represent a hydrogen atom or a methyl group;
L ² may be an ether bond oxygen atom between carbon-carbon bonds, some or all of the hydrogen atoms may be substituted with fluorine atoms, and may have COO, OCO or O at a position at which they bond to E ²¹ , An alkyl group having 1 to 8 carbon atoms.
M ² may be an ether bond oxygen atom between carbon-carbon bonds, some or all of the hydrogen atoms may be substituted with fluorine atoms, and may have COO, OCO or O at a position at which they bond to E ²³ . An alkyl group having 1 to 8 carbon atoms.
E ²¹ , E ²² and E ²³ each independently represents a trans-1,4-cyclohexylene group or a trans-2,6-decahydronaphthalene group in which the hydrogen atom bonded to the carbon atom in the group is a fluorine atom or a methyl group ).
S ² and T ² are each independently -OCO-, -COO-, - (CH ₂ ) ₂ -, -CH ₂ O-, -OCH ₂ - or a single bond.
a2, b2, c2, d2 and e2: independently 0 or 1.) 5. The method according to any one of claims 1 to 4,
The second photopolymerizable liquid crystal (B) is a photopolymerizable liquid crystal composition represented by the following formula (20).
Q ¹ -Z ¹ -A ¹ -Z ³ -MZ ⁴ -A ² -Z ² -Q ² (20)
(Wherein the symbols in the formulas have the following meanings.
Q ¹ and Q ² are each independently a photopolymerizable reactive group.
Z ¹ , Z ² , Z ³ and Z ⁴ : each independently a single bond or a divalent linking group.
A ¹ and A ² : each independently a spacer group having 2 to 20 carbon atoms.
M: a mesogenic group containing an aromatic ring) 6. The method of claim 5,
And the second photopolymerizable liquid crystal (B) is a photopolymerizable liquid crystal composition containing a photopolymerizable liquid crystal represented by the following formula (21).
^{_{CH 2 = CR 41 -COO- (E}} 41) m4 -Cy-Y 4 -Cy- (E 42) n4 -OCO-CR 42 = CH 2 ··· (21)
(Wherein the symbols in the formulas have the following meanings.
R ⁴¹ and R ⁴² each independently represent a hydrogen atom or a methyl group;
Y ⁴ : -OCO- or -COO-.
m4 and n4 are each independently 0 or 1 (provided that both are not 0).
E ⁴¹ and E ⁴² : each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group. Provided that at least one of E ⁴¹ and E ⁴² is a 1,4-phenylene group.
Cy: trans-1,4-cyclohexylene group. However, in the 1,4-phenylene group and the trans-1,4-cyclohexylene group, the hydrogen atom in the group may be substituted with a fluorine atom, a chlorine atom or a methyl group.) 6. The method of claim 5,
And the second photopolymerizable liquid crystal (B) is a photopolymerizable liquid crystal composition containing a photopolymerizable liquid crystal represented by the following formula (22).
^{_{CH 2 = CR 51 -COO- (L}} 5) k5 -E 51 -E 52 -E 53 -E 54 - (M 5) n5 -OCO-CR 52 = CH 2 ··· (22)
(Wherein the symbols in the formulas have the following meanings.
R ⁵¹ and R ⁵² each independently represents a hydrogen atom or a methyl group;
k5 and n5: independently 0 or 1;
L ^{5 is} - (CH ₂ ) _p ⁵ O- or - (CH ₂ ) _p5 - (wherein p5 is an integer of 2 to 8).
_{^{M 5: -O (CH 2)}} p5 - or - (CH _{2) p5} - (wherein, p5 is an integer of 2-8.).
E ⁵¹ : 1,4-phenylene group.
E ⁵² , E ⁵³ and E ⁵⁴ each independently represent a 1,4-phenylene group or a trans-1,4-cyclohexylene group, and at least one of E ⁵² and E ⁵³ is trans-1,4-cyclohexylene group. However, in the 1,4-phenylene group and the trans-1,4-cyclohexylene group, the hydrogen atom bonded to the carbon atom in the group may be substituted by a fluorine atom, a chlorine atom or a methyl group.) 6. The method of claim 5,
And the second photopolymerizable liquid crystal (B) is a photopolymerizable liquid crystal composition containing a photopolymerizable liquid crystal represented by the following formula (23).
^{_{CH 2 = CR 61 -COO- (L}} 6) k6 -E 61 -E 62 -E 63 - (M 6) n6 -OCO-CR 62 = CH 2 ··· (23)
(Wherein the symbols in the formulas have the following meanings.
R ⁶¹ and R ⁶² : each independently represents a hydrogen atom or a methyl group;
k6 and n6 are each independently 0 or 1;
_{^{L 6: - (CH 2)}} p6 O-, -Cy-COO- (. Cy is trans-1,4-cyclohexylene group), or -Cy-OCO- (wherein, p6 is an integer of 2-8. ).
_{^{M 6: -O (CH 2)}} p6 -, -OCO-Cy- (. Cy is trans-1,4-cyclohexylene group), or -COO-Cy- (here, p6 is an integer of 2-8. ).
E ⁶¹ , E ⁶² and E ⁶³ : each independently a 1,4-phenylene group or a trans-1,4-cyclohexylene group. Provided that at least one of E ⁶¹ , E ⁶² and E ⁶³ is a 1,4-phenylene group and at least one is a trans-1,4-cyclohexylene group. Also, L ⁶ is E ⁶¹ in the case of trans-1,4-cyclohexyl is -Cy-OCO-, and xylene group, L ⁶ is - (CH ₂₎ and E ⁶¹ in the case where the _p6 or O- or k6 is 0, Each E ⁶³ is a 1,4-phenylene group, and E ⁶² is a trans-1,4-cyclohexylene group. However, in the 1,4-phenylene group and the trans-1,4-cyclohexylene group, the hydrogen atom bonded to the carbon atom in the group may be substituted by a fluorine atom, a chlorine atom or a methyl group.) 6. The method of claim 5,
And the second photopolymerizable liquid crystal (B) is a photopolymerizable liquid crystal composition containing a photopolymerizable liquid crystal represented by the following formula (24).
^{_{CH 2 = CR 71 -COO- (L}} 7) k7 -Ph- (X 7) -Ph- (Y 7) -Ph- (M 7) n7 -OCO-CR 72 = CH 2 ··· (24)
(Wherein the symbols in the formulas have the following meanings.
R ⁷¹ and R ⁷² each independently represent a hydrogen atom or a methyl group;
X ⁷ and Y ⁷ : each independently -OCO- or -COO-.
L ^{7 is} - (CH ₂ ) _p ⁷ O-, - (CH ₂ ) _{p 7} O-COO-, - (CH ₂ ) _{p 7} OCO- or - (CH ₂ ) _{p 7} COO- wherein p7 is an integer of 2 to 8 .).
_{^{M 7: -O (CH 2)}} p7 -, OCO-O (CH 2) p7 -, -OCO- (CH 2) p7 or -COO (CH _{2) p7} - (here, p7 is an integer of 2-8. ).
k7 and n7: independently 0 or 1. Ph: 1,4-phenylene group. However, in the 1,4-phenylene group, the hydrogen atom bonded to the carbon atom in the group may be substituted by a fluorine atom, a chlorine atom or a methyl group.) An optical compensation film exhibiting positive uniaxial anisotropy, obtained by photo-curing a coating film of the photopolymerizable liquid crystal composition according to any one of claims 1 to 9. An optical compensation laminated film having an optical compensation film exhibiting negative uniaxial anisotropy and an optical compensation film showing positive uniaxial anisotropy described in claim 10 laminated on the optical compensation film. 12. The method of claim 11,
Wherein the optical compensation film exhibiting negative uniaxial anisotropy contains a polyimide having an aliphatic ring in its skeleton. An electrode substrate having the optical compensation laminate film according to claim 12 and an electrode formed on the optical compensation laminate film on a substrate. A liquid crystal display device substrate having the electrode substrate according to claim 13 and an alignment film formed on the electrode substrate. A liquid crystal display device comprising the liquid crystal substrate according to claim 14, an opposing substrate, and a liquid crystal layer sandwiched between the liquid crystal substrate and the opposing substrate.

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