TWI628209B - Manufacturing method of substrate with liquid crystal alignment film for lateral electric field drive type liquid crystal display element - Google Patents

Abstract

The present invention provides a lateral electric field drive type liquid crystal display device capable of imparting alignment control ability with high efficiency and excellent afterimage characteristics. The present invention solves the above-mentioned problems by a method for manufacturing a substrate having the above-mentioned liquid crystal alignment film by obtaining the liquid crystal alignment film for a transverse electric field drive type liquid crystal display element provided with alignment control energy by having the following steps. [I] will contain (A) A step of applying a polymer composition of a photosensitive side chain polymer and (B) an organic solvent exhibiting liquid crystallinity in a specific temperature range to a substrate having a conductive film for lateral electric field drive to form a coating film; [II ] A step of irradiating polarized ultraviolet rays on the coating film obtained in [I]; [III] step of heating the coating film obtained in [II]; and [IV] cooling the coating film heated in [III] to less than A step of heating the glass transition temperature to a temperature above the glass transition temperature of the coating film surface.

Description

Manufacturing method of substrate with liquid crystal alignment film for lateral electric field drive type liquid crystal display element

The present invention relates to a method for manufacturing a substrate having a liquid crystal alignment film for a liquid crystal display element driven in a lateral electric field. More specifically, it relates to a novel method for manufacturing a liquid crystal display element having excellent afterimage characteristics.

It is known that a liquid crystal display element is a lightweight, thin, and low power consumption display device. In recent years, it has been used in large-scale television applications and the like. The liquid crystal display element is configured, for example, by sandwiching a liquid crystal layer on a transparent substrate with one of the electrodes. In addition, the liquid crystal display element makes a liquid crystal into a desired alignment state between substrates, and an organic film made of an organic material is used as the liquid crystal alignment film.

That is, the constituent member of the liquid crystal alignment film-based liquid crystal display element is formed on a surface in contact with the liquid crystal of the substrate holding the liquid crystal, and plays a role of orienting the liquid crystal in a certain direction between the substrates. In addition, in addition to the role of the liquid crystal alignment film in a certain direction such as the direction in which the liquid crystal is aligned parallel to the substrate, the role of controlling the pretilt angle of the liquid crystal is sometimes required. The ability to control liquid crystal alignment in such a liquid crystal alignment film (hereinafter referred to as alignment Orientation control energy) is imparted by performing an alignment treatment on an organic film constituting a liquid crystal alignment film.

An alignment treatment method for imparting a liquid crystal alignment film that can be used for alignment control has been conventionally known as a rubbing method. The so-called rubbing method is to wipe (friction) the surface of the organic film such as polyvinyl alcohol, polyimide, or polyimide on the substrate with a cloth such as cotton, nylon, or polyester in a certain direction, so that the liquid crystal faces the wiping direction (friction Direction). Since this rubbing method can easily achieve a relatively stable alignment state of the liquid crystal, it is used in a conventional manufacturing process of a liquid crystal display element. In addition, as the organic film used for the liquid crystal alignment film, a polyimide-based organic film having excellent reliability such as heat resistance or excellent electrical characteristics is mainly selected.

However, the rubbing method of wiping the surface of a liquid crystal alignment film made of polyimide or the like has a problem of generating dust or generating static electricity. In addition, in recent years, due to the high definition of the liquid crystal display element or the unevenness caused by the electrodes on the corresponding substrate or the active element for switching the liquid crystal drive, the liquid crystal alignment film cannot be uniformly wiped with a cloth. On the surface, uniform liquid crystal alignment sometimes cannot be achieved.

Therefore, the photo-alignment method is actively reviewed as another alignment processing method of the liquid crystal alignment film without rubbing.

There are various methods of photo-alignment, but anisotropy is formed in the organic film constituting the liquid crystal alignment film by linear polarized light or collimate light, and the liquid crystal is aligned according to the anisotropy.

As the main photo-alignment method, a decomposition-type photo-alignment method is known. In this method, for example, a polyimide film is irradiated with polarized ultraviolet rays, and the polarization direction dependence of ultraviolet absorption of a molecular structure is used to cause anisotropic decomposition. and Then, the liquid crystal is aligned by using polyimide remaining without being decomposed (see, for example, Patent Document 1).

In addition, other photo-alignment methods such as a photo-crosslinking type or a photo-isomerization type are also known. The photo-crosslinking type photo-alignment method uses, for example, polyvinyl cinnamate and irradiates polarized ultraviolet rays to cause a dimerization reaction (cross-linking reaction) in a double bond portion of two side chains parallel to the polarized light. In addition, the liquid crystal is aligned in a direction orthogonal to the polarization direction (see, for example, Non-Patent Document 1). Photoisomerization type photo-alignment method. When using a side-chain type polymer with azobenzene on the side chain, it is irradiated with polarized ultraviolet light to generate an isomerization reaction in the azobenzene portion of the side chain parallel to the polarization. The liquid crystal is aligned in a direction orthogonal to the polarization direction (see, for example, Non-Patent Document 2).

As in the above example, the alignment processing method of the liquid crystal alignment film by the photo alignment method does not require friction, and there is no doubt that dust or static electricity is generated. In addition, even a substrate of a liquid crystal display element having an uneven surface can be subjected to an alignment treatment, which becomes an alignment treatment method of a liquid crystal alignment film suitable for an industrial production process.

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 3893659

[Non-patent literature]

[Non-Patent Document 1] M. Shadt et al., Jpn. J. Appl. Phys. 31, 2155 (1992)

[Non-Patent Document 2] K. Ichimura et al., Chem. Rev. 100, 1847 (2000)

As described above, the photo-alignment method, as an alignment processing method for a liquid crystal display element, has a great advantage because it does not require a rubbing step as compared with the conventional rubbing method used in industry. In addition, compared with a friction method that uses friction to make the alignment control energy approximately constant, the light alignment method can change the irradiation amount of polarized light to control the alignment control energy. However, when the photo-alignment method wants to achieve the same degree of alignment control ability as in the case of using the friction method, a large amount of polarized light irradiation is required, and sometimes a stable liquid crystal alignment cannot be achieved.

For example, in the decomposition-type light alignment method described in Patent Document 1, the polyimide film must be irradiated with ultraviolet light from a high-pressure mercury lamp with an output of 500 W for 60 minutes, etc., and a large amount of ultraviolet light must be irradiated for a long time. Moreover, in the case of the photo-alignment method of a dimerization type or a photo-isomerization type, it may be necessary to irradiate a large amount of ultraviolet rays of several J (Joules) to several tens J. Furthermore, in the photo-alignment method of the photo-crosslinking type or the photo-isomerization type, the liquid crystal alignment has poor thermal stability or photo-stability. Therefore, when it is used as a liquid crystal display element, poor alignment or display afterimage may occur. In particular, in a liquid crystal display element driven by a lateral electric field, since liquid crystal molecules are switched in-plane, alignment of the liquid crystal is likely to be shifted after the liquid crystal is driven, which causes a large problem of display sticking caused by AC driving.

Therefore, the photo-alignment method requires high-efficiency or stable liquid crystal alignment for alignment processing, and a liquid-crystal alignment film or liquid-crystal alignment agent capable of efficiently imparting high alignment control ability to the liquid-crystal alignment film, and an alignment method.

An object of the present invention is to provide a substrate having a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element capable of imparting alignment control ability with high efficiency and excellent afterimage characteristics, and a lateral electric field drive type liquid crystal display element having the substrate. In addition, an object of the present invention is to provide a method for manufacturing a substrate for a liquid crystal alignment film, which can expand a margin region of a polarized ultraviolet irradiation amount that can achieve good liquid crystal alignment of the liquid crystal alignment film.

The present inventors have actively reviewed the results in order to achieve the above-mentioned problems, and have found the following inventions.

<1> A method for manufacturing a substrate with a liquid crystal alignment film, which comprises the following steps to obtain a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element that is provided with alignment control energy: [I] will contain (A) in Step of forming a coating film by coating a photosensitive side-chain polymer exhibiting liquid crystallinity and a polymer composition of (B) an organic solvent in a specific temperature range on a substrate having a conductive film for lateral electric field driving; [II] A step of irradiating the coating film obtained in [I] with polarized ultraviolet light; [III] a step of heating the coating film obtained in [II]; and [IV] A step of cooling the coating film heated with [III] to a temperature not higher than the glass transition temperature of the surface of the coating film, and then heating to a temperature higher than the glass transition temperature.

<2> In the above <1>, the cooling temperature of the coating film in the step [IV] is a temperature lower than the glass transition point temperature (Tg) of the side chain polymer of the component (A) by at least 10 ° C.

<3> In the above <1> or <2>, the heating temperature of the coating film after ultraviolet irradiation and the reheating temperature after cooling are above the glass transition temperature of the coating film surface, and do not reach the isotropic property of the coating film surface. Phase transition (Isotropic Phase Transition) temperature.

<4> In any one of the above <1> to <3>, the component (A) has a photosensitive side chain that causes photocrosslinking, photoisomerization, or optical Fries rearrangement.

<5> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (1) to (6):

(Wherein A, B, and D each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O -Or-O-CO-CH = CH-; S is an alkylene group having 1 to 12 carbon atoms, and the hydrogen atoms to which they are bonded may be substituted with a halogen group; T is a single bond or 1 to carbon number 12 alkyl groups, and the hydrogen atoms to which they are bonded may be substituted with halogen groups; Y ₁ represents a monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, and carbon number 5 ~ 8 alicyclic hydrocarbon rings, or the same or different 2 ~ 6 rings selected from their substituents are bonded through a bonding group B, and the hydrogen atoms to which they are bonded can be independent of each other Via -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, C1-C5 alkyl group or C1-C5 alkyloxy group is substituted; Y ₂ is selected from bivalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, carbon number 5 ~ The alicyclic hydrocarbons of 8 and the groups of these groups, and the hydrogen atoms to which they are bonded can also independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, 1 to 5 carbons, or 1 to 5 carbons Alkyloxy substitution; R represents a hydroxyl group, an alkoxy group having 1 to 6 carbon atoms, or the same definition as Y ₁ ; X represents a single bond, -COO-, -OCO-, -N = N-,- CH = CH-, -C≡C-, -CH = CH-CO-O-, or -O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; Cou means fragrance 6-yl or coumarin-7-yl, and the hydrogen atoms to which they are bonded may each independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH- CN, halo, alkyl having 1 to 5 carbons, or alkyloxy having 1 to 5 carbons; one of q1 and q2 is 1 and the other is 0; q3 is 0 or 1; P and Q is each independently a group selected from the group consisting of a divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, an alicyclic hydrocarbon having 5 to 8 carbon atoms, and a combination thereof, but X When -CH = CH-CO-O-, -O-CO-CH = CH-, P or Q on the side to which -CH = CH- is bonded is an aromatic ring, and when the number of P is 2 or more, P It may be the same or different. When the number of Q is 2 or more, Q may be the same or different; l1 is 0 or 1; l2 is an integer of 0 ~ 2; when l1 and l2 are 0, and T is a single bond, A also represents a single bond; when l1 is 1, and T is a single bond, B also represents a single bond; H and I are independent Is selected from the divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and combinations of those of the group).

<6> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (7) to (10):

In the formula, A, B, D, Y ₁ , X, Y ₂ , and R have the same definitions as above; l represents an integer of 1 to 12; m represents an integer of 0 to 2; m1 and m2 represent 1 to 3; Integer; n represents an integer from 0 to 12 (but when n = 0, B is a single bond).

<7> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (11) to (13):

In the formula, A, X, 1, m, m1, and R have the same definitions as described above.

<8> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain represented by the following formula (14) or (15):

In the formula, A, Y ₁ , 1, m1 and m2 have the same definitions as above.

<9> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain represented by the following formula (16) or (17):

In the formula, A, X, l, and m have the same definitions as described above.

<10> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain represented by the following formula (18) or (19):

(Wherein A, B, Y ₁ , q1, q2, m1, and m2 have the same definitions as above; R ₁ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, alkyl having 1 to 5 carbons, or alkyloxy having 1 to 5 carbons).

<11> In any one of the above <1> to <4>, the component (A) has a photosensitive side chain represented by the following formula (20):

In the formula, A, Y ₁ , X, l, and m have the same definitions as above.

<12> In any one of the above <1> to <11>, the component (A) has a liquid crystal side chain selected from the group consisting of the following formulae (21) to (31):

(In the formula, A, B, q1, and q2 have the same definitions as above; Y ₃ is selected from the group consisting of monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, and 5 to 8 carbon atoms. Alicyclic hydrocarbons, and groups of groups thereof, and the hydrogen atoms to which they are bonded may each independently pass -NO ₂ , -CN, halo, 1 to 5 carbon alkyl groups, or C1-C5 alkyloxy substitution; R ₃ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, monovalent benzene ring, Naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, alicyclic hydrocarbon having 5 to 8 carbons, alkyl having 1 to 12 carbons, or alkoxy having 1 to 12 carbons; l represents 1 to An integer of 12 and m represents an integer of 0 to 2. However, in formulas (23) to (24), the total of all m is 2 or more, and in formulas (25) to (26), the total of all m is 1 or more, m1 , M2 and m3 each independently represent an integer of 1 to 3; R ₂ represents a hydrogen atom, -NO ₂ , -CN, halo, monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, And alicyclic hydrocarbons and alkyl or alkyloxy groups having 5 to 8 carbons; Z ₁ and Z ₂ represent single bonds, -CO-, -CH ₂ O-, -CH = N-, -CF _2- ) .

<13> A substrate having a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element, characterized by being manufactured by any one of the methods of <1> to <12>.

<14> A lateral electric field drive type liquid crystal display element, comprising the substrate according to <13>.

<15> A method for manufacturing a liquid crystal display element, which is characterized by obtaining a lateral electric field drive type liquid crystal display element by the following steps: the step of preparing the substrate (first substrate) of the above <13>; and obtaining the liquid crystal alignment film having the aforementioned liquid crystal alignment film. The step of the second substrate is to obtain a liquid crystal alignment film that imparts alignment control ability by having the following steps [I '] to [III']: [I '] coating the second substrate with the following component (A) And (B) the polymer composition to form a coating film: (A) a photosensitive side chain polymer that exhibits liquid crystallinity in a specific temperature range, and (B) an organic solvent; [II '] to [I '] The step of irradiating the obtained coating film with polarized ultraviolet light; [III'] The step of heating the coating film obtained by [II ']; and [V] The step of obtaining a liquid crystal display element, which is performed by liquid crystal The liquid crystal alignment films of the first and second substrates face each other, and the first and second substrates are arranged to face each other.

<16> In the above <15>, the step of obtaining the second substrate The method further includes a step of [IV '] cooling the coating film heated with [III'] to a temperature below the glass transition temperature of the coating film surface, and then heating the coating film to a temperature higher than the glass transition temperature.

<17> A lateral electric field drive type liquid crystal display element, characterized in that it is manufactured by the method of <15> or <16>.

In addition, the following inventions were found.

<P1> A method for manufacturing a substrate having a liquid crystal alignment film, which comprises the following steps to obtain a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element that is provided with alignment control energy: [I] will contain (A) in Step of forming a coating film by coating a photosensitive side-chain polymer exhibiting liquid crystallinity and a polymer composition of (B) an organic solvent in a specific temperature range on a substrate having a conductive film for lateral electric field driving; [II] The step of irradiating the coating film obtained in [I] with polarized ultraviolet light; [III] the step of heating the coating film obtained in [II]; and [IV] cooling the coating film heated in [III] until the coating is not reached The step of heating the glass transition temperature to a temperature above the glass transition temperature after the film surface.

<P2> In the above <P1>, the cooling temperature of the coating film in the step [IV] is a temperature lower than the glass transition point temperature (Tg) of the side chain polymer of the component (A) by at least 10 ° C.

<P3> In the above <P1> or <P2>, the heating temperature of the coating film after ultraviolet irradiation and the reheating temperature after cooling are above the glass transition temperature of the coating film surface and do not reach the isotropy of the coating film surface. 1. phase change Transition) temperature.

<P4> In any one of <P1> to <P3>, the component (A) may have a photosensitive side chain that causes photocrosslinking, photoisomerization, or optical Fries rearrangement.

<P5> In any one of the above <P1> to <P4>, the component (A) may have a photosensitive side chain selected from the group consisting of the following formulae (1) to (6):

In the formula, A, B, and D each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O- , Or -O-CO-CH = CH-; S is an alkylene group having 1 to 12 carbon atoms, and the hydrogen atom to which they are bonded may be substituted with a halogen group; T is a single bond or 1 to 12 carbon atoms An alkylene group of 12 and the hydrogen atom bonded thereto may be substituted with a halogen group; Y ₁ represents a monovalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and a carbon number of 5 ~ 8 alicyclic hydrocarbon rings, or the same or different 2 ~ 6 ring systems selected from these substituents are bonded through the bonding group B, and the hydrogen atom bonded to it can also be Each independently via -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halogen Group, 1 to 5 carbon atoms, or 1 to 5 alkyloxy groups; Y ₂ is selected from a divalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, carbon number The alicyclic hydrocarbons of 5 to 8 and the bases of a group composed of these, and the hydrogen atoms bonded thereto may also independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, alkyl with 1 to 5 carbons, or carbon The alkyl group having 1 to 5 substituents; R & lt represents a hydroxyl group, an alkoxy group having a carbon number of 1 to 6, or represents the same as defined in the Y _1; X represents a single bond, -COO -, - OCO -, - N = N -, -CH = CH-, -C≡C-, -CH = CH-CO-O-, or -O-CO-CH = CH-, Cou represents coumarin-6-yl or coumarin-7 -Groups, and the hydrogen atoms bonded to them may each independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, 1 to 5 carbon alkane Or an alkyloxy group with 1 to 5 carbon atoms; one of q1 and q2 is 1 and the other is 0; q3 is 0 or 1; P and Q are each independently selected from a single bond and a divalent A group consisting of a benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, an alicyclic hydrocarbon having 5 to 8 carbon atoms, and a combination of these, but X is -CH = CH-CO- When O-, -O-CO-CH = CH-, P or Q on the side to which -CH = CH- is bonded is an aromatic ring, and H and I are each independently selected from a divalent benzene ring, naphthalene ring, and A benzene ring, a furan ring, a pyrrole ring, and a combination thereof.

<P6> In any one of the above <P1> to <P4>, the (A) component may have a photosensitive side chain selected from the group consisting of the following formulae (7) to (10).

In the formula, A, B, D, Y ₁ , X, Y ₂ and R have the same definitions as above; l represents an integer from 1 to 12; m represents an integer from 0 to 2; m1 and m2 represent integers from 1 to 3 ; N represents an integer from 0 to 12 (but B is a single bond when n = 0).

<P7> In any one of the above-mentioned <P1> to <P4>, the component (A) may have a photosensitive side chain selected from the group consisting of the following formulae (11) to (13).

In the formula, A, X, 1, m and R have the same definitions as above.

<P8> In any one of the above <P1> to <P4>, the (A) component may have a photosensitive side chain represented by the following formula (14) or (15).

In the formula, A, Y ₁ , X, 1, m1 and m2 have the same definitions as above.

<P9> In any one of <P1> to <P4>, the component (A) may have a photosensitive side chain represented by the following formula (16) or (17).

In the formula, A, X, l, and m have the same definitions as described above.

<P10> In any one of the above <P1> to <P4>, the component (A) may have a photosensitive side chain represented by the following formula (18) or (19).

In the formula, A, B, Y ₁ , q1, q2, m1 and m2 have the same definitions as above, and R ₁ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH -CN, halo, alkyl having 1 to 5 carbons, or alkyloxy having 1 to 5 carbons.

<P11> In any one of <P1> to <P4>, the component (A) may have a photosensitive side chain represented by the following formula (20).

In the formula, A, Y ₁ , X, l, and m have the same definitions as above.

<P12> In any one of the above <P1> to <P11>, the (A) component may have any liquid crystal side chain selected from the group consisting of the following formulae (21) to (31).

In the formula, A, B, q1, and q2 have the same definitions as above; Y ₃ is selected from the group consisting of monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, and lipid having 5 to 8 carbon atoms. Cyclic hydrocarbons, and groups of groups of these, the hydrogen atoms bonded to them may each independently pass -NO ₂ , -CN, halo, 1 to 5 carbon alkyl groups, or carbon 1 to 5 alkyloxy substitution; R ₃ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, monovalent benzene ring, naphthalene Ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, alicyclic hydrocarbon having 5 to 8 carbons, alkyl having 1 to 12 carbons, or alkoxy having 1 to 12 carbons; l represents 1 to 12 Integer, m represents an integer from 0 to 2, but in formulas (25) to (26), the total of all m is 2 or more, and in formulas (27) to (28), the total of all m is 1 or more, m1, m2 and m3 each independently represent an integer of 1 to 3; R ₂ represents a hydrogen atom, -NO ₂ , -CN, a halogen group, a monovalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a nitrogen-containing heterocyclic ring, and Alicyclic hydrocarbons having 5 to 8 carbon atoms, and alkyl or alkyloxy groups; Z ₁ and Z ₂ represent single bonds, -CO-, -CH ₂ O-, -CH = N-, -CF _2- .

<P13> A substrate having a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element, which is manufactured by any one of the above-mentioned <P1> to <P12>.

<P14> A lateral electric field drive type liquid crystal display device having the substrate of <P13>.

<P15> A method for manufacturing a liquid crystal display element, which obtains a lateral electric field drive type liquid crystal display element by having the following steps: The step of preparing the substrate (the first substrate) of the above-mentioned <P13>; the step of obtaining the second substrate having the aforementioned liquid crystal alignment film is to obtain the ability to impart alignment control by having the following steps [I '] to [III'] Liquid crystal alignment film: [I '] Coating a polymer composition containing the following components (A) and (B) on a second substrate to form a coating film: (A) Displaying liquid crystal in a specific temperature range Photosensitive side-chain polymers, and (B) organic solvents; [II '] a step of irradiating polarized ultraviolet rays on the coating film obtained in [I']; [III '] using [II'] The step of heating the coating film; and [V] the step of obtaining a liquid crystal display element, in which the liquid crystal alignment films of the first and second substrates are opposed to each other through liquid crystal, and the first and second substrates are arranged to face each other.

<P16> In the above-mentioned <P15>, the step of obtaining the second substrate further includes [IV '] cooling the coating film heated with [III'] to a temperature below the glass transition temperature of the coating film surface, and then A step of heating to a temperature above the glass transition temperature.

<P17> A lateral electric field drive type liquid crystal display device manufactured by the method of <P15> or <P16> described above.

According to the present invention, it is possible to provide a liquid crystal display element with a lateral electric field drive type capable of imparting alignment control energy with high efficiency and excellent afterimage characteristics. A substrate for a liquid crystal alignment film for a device and a lateral electric field drive type liquid crystal display element having the substrate.

The lateral electric field drive type liquid crystal display element manufactured by the manufacturing method of the present invention can provide alignment control energy with high efficiency, so it does not damage the display characteristics even if it is continuously driven for a long time.

In addition, according to the present invention, a margin area where the amount of polarized light irradiation can achieve a good liquid crystal alignment of the liquid crystal alignment film can be expanded, and the area of the irradiation amount is wide, so that a wider irradiation area can achieve a desired effect.

1‧‧‧ side chain polymer film

2, 2a‧‧‧ side chain

3‧‧‧ side chain polymer film

4, 4a‧‧‧ side chain

5‧‧‧ side chain polymer film

6, 6a‧‧‧ side chain

7‧‧‧ side chain polymer film

8, 8a‧‧‧ side chain

[Fig. 1] A diagram schematically illustrating an example of anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film used in the present invention. A crosslinkable organic group is used for a photosensitive side chain, and the introduced anisotropy is small. Of the situation.

[Fig. 2] A diagram schematically illustrating an example of anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film used in the present invention. A crosslinkable organic group is used for a photosensitive side chain, and the introduced anisotropy is large. Of the situation.

[Fig. 3] A diagram schematically illustrating an example of anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film used in the present invention. An organic material that causes photo-Fries rearrangement or isomerization is used on a photosensitive side chain. Base, a diagram of the case where the introduced anisotropy is small.

[Fig. 4] A diagram schematically illustrating an example of anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film used in the present invention. An organic material that causes photo-Fries rearrangement or isomerization is used on a photosensitive side chain. Anisotropy Figure of a big situation.

As a result of active research by the present inventors, the following findings were obtained and the present invention has been completed.

The polymer composition used in the production method of the present invention has a photosensitive side chain polymer (hereinafter also simply referred to as a side chain polymer) that exhibits liquid crystallinity. The coating film obtained by using the polymer composition described above has A film of a photosensitive side chain polymer exhibiting liquid crystallinity. This coating film does not need to be subjected to rubbing treatment, but is subjected to alignment treatment by polarized light irradiation. After the polarized light is irradiated, the side chain polymer film is heated to obtain a coating film (hereinafter, also referred to as a liquid crystal alignment film) to which alignment control ability is given. At this time, a slight anisotropy exhibited by polarized light irradiation becomes a driving force, and the liquid crystal side chain polymer itself is effectively realigned due to self-organization. As a result, a highly efficient alignment process as a liquid crystal alignment film can be realized, and a liquid crystal alignment film to which a high alignment control ability is given can be obtained.

The present inventors can heat the side-chain polymer film after polarized light irradiation, and then cool it and then heat it to obtain a coating film with alignment control ability, so it can widen the margin of polarized light irradiation. , A liquid crystal alignment film having good liquid crystal alignment can be obtained. The present invention is based on this finding.

Hereinafter, embodiments of the present invention will be described in detail.

<Manufacturing method of substrate with liquid crystal alignment film> and <Manufacturing method of liquid crystal display element>

The method for manufacturing a substrate with a liquid crystal alignment film of the present invention has the following steps: [I] A polymer containing (A) a photosensitive side chain polymer exhibiting liquid crystallinity in a specific temperature range and (B) an organic solvent A step of coating the composition on a substrate having a conductive film for driving a lateral electric field to form a coating film; [II] a step of irradiating polarized ultraviolet rays on the coating film obtained in [I]; [III] applying a coating obtained in [II] A step of heating the coating film; and [IV] a step of cooling the coating film heated by [III] to a temperature below the glass transition temperature of the surface of the coating film, and then heating to a temperature above the glass transition temperature.

According to the above steps, a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element to which alignment control ability is given can be obtained, and a substrate having the liquid crystal alignment film can be obtained.

In addition to the substrate (first substrate) obtained above, a second substrate can be prepared to obtain a lateral electric field drive type liquid crystal display element.

The second substrate uses a substrate without a conductive film for lateral electric field drive instead of a substrate with a conductive film for lateral electric field drive, by using the above steps [I] to [III] The substrate of the conductive film is sometimes referred to as steps [I '] to [III'] for convenience in this application, and a second substrate having a liquid crystal alignment film to which alignment control ability is given can be obtained.

A method for manufacturing a lateral electric field-driven liquid crystal display device has the following steps [V]: [V] The method of opposing the liquid crystal alignment films of the first and second substrates via liquid crystal, and causing the first and second substrate pairs obtained above to A step of arranging to obtain a liquid crystal display element. Thereby, a lateral electric field drive type liquid crystal display element can be obtained.

Hereinafter, each step of [I] to [IV] and [V] included in the manufacturing method of the present invention will be described.

<Step [I]>

Step [I] is to form a coating film by coating a polymer composition containing a photosensitive side chain polymer and an organic solvent exhibiting liquid crystallinity in a specific temperature range on a substrate having a conductive film for lateral electric field driving. .

<Substrate>

The substrate is not particularly limited, but when the manufactured liquid crystal display element is a transmissive type, it is preferable to use a substrate with high transparency. In this case, there is no particular limitation, and a glass substrate, a plastic substrate such as an acrylic substrate, or a polycarbonate substrate can be used.

In addition, considering the application of a reflective liquid crystal display element, an opaque substrate such as a silicon wafer may be used.

<Conductive film for lateral electric field drive>

The substrate has a conductive film for driving a lateral electric field.

When the conductive film is of a transmissive type, the conductive film may be ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), or the like, but is not limited thereto.

In the case of a reflective liquid crystal display element, the conductive film may be a material that reflects light, such as aluminum, but is not limited thereto.

As a method for forming a conductive film on a substrate, a conventionally known method can be used.

<Polymer composition>

A polymer composition is coated on a substrate having a conductive film for driving a lateral electric field, especially a conductive film.

The polymer composition used in the production method of the present invention contains (A) a photosensitive side chain polymer that exhibits liquid crystallinity in a specific temperature range; and (B) an organic solvent.

<< (A) side chain polymer >>

The component (A) is a photosensitive side chain polymer that exhibits liquid crystallinity in a specific temperature range.

(A) The side-chain polymer needs to react with light in a wavelength range of 250 nm to 400 nm and display liquid crystallinity in a temperature range of 100 ° C to 300 ° C.

(A) The side chain polymer is preferably a photosensitive side chain that reacts with light in a wavelength range of 250 nm to 400 nm.

(A) The side chain polymer system exhibits liquid crystallinity in a temperature range of 100 ° C to 300 ° C, and therefore it is preferable to have a mesogenic group.

(A) A side chain type polymer-based main chain is bonded to a photosensitive side chain, which causes a crosslinking reaction, an isomerization reaction, or a light Fryce rearrangement to be induced by light. The structure of the photosensitive side chain is not particularly limited, and it is preferably a structure that induces a cross-linking reaction or photo-Fries rearrangement by light induction, and more preferably a cross-linking reaction. At this time, even if exposed to external stress such as heat, the achieved alignment control performance can be stably maintained for a long time. The structure of the photosensitive side chain polymer film exhibiting liquid crystallinity is not particularly limited as long as it satisfies this characteristic, but it is preferred that it has a rigid liquid crystal component on the side chain structure. In this case, when the side chain polymer is used as a liquid crystal alignment film, a stable liquid crystal alignment can be obtained.

The structure of the polymer may be, for example, a main chain and a side chain bonded thereto, and the side chain has biphenyl, terphenyl, phenylcyclohexyl, phenylbenzoate, azophenyl, etc. The liquid crystal component has a structure of a photosensitive group that is crosslinked or isomerized by light-sensing, which is bonded to the front end, or has a main chain and a side chain bonded thereto, and the side chain has a liquid crystal component. The structure of a phenylbenzoate group that undergoes a photo-Fries rearrangement reaction.

A more specific example of the structure of the photosensitive side chain polymer film capable of exhibiting liquid crystallinity is preferably one selected from the group consisting of hydrocarbons, (meth) acrylates, itaconates, fumarates, and horses. Free radically polymerizable groups such as maleic acid esters, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, norbornene, and at least 1 The structure of the main chain composed of species and the side chain composed of at least one of the following formulae (1) to (6).

In the formula, A, B, and D each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O- , Or -O-CO-CH = CH-; S is an alkylene group having 1 to 12 carbon atoms, and the hydrogen atoms to which they are bonded may be substituted with a halogen group; T is a single bond or 1 to 12 carbon atoms Alkyl groups, and the hydrogen atoms to which they are bonded may be substituted with halogen groups; Y ₁ represents a monovalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and a carbon number of 5 to 8 Alicyclic hydrocarbon rings, or the same or different 2 to 6 rings selected from their substituents are bonded through a bonding group B, and the hydrogen atoms to which they are bonded can also be independently passed through -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, carbon 1 to 5 alkyl or 1 to 5 carbon oxy; Y ₂ is selected from the group consisting of a divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and a carbon number of 5 to 8 Alicyclic hydrocarbons, and the groups of their combinations, and the hydrogen atoms to which they are bonded can also independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH -CN, halo, alkyl having 1 to 5 carbons, or alkane having 1 to 5 carbons Substituent group; R & lt represents a hydroxyl group, an alkoxy group having a carbon number of 1 to 6, or the same meanings as Y _1; X represents a single bond, -COO -, - OCO -, - N = N -, - CH = CH- , -C≡C-, -CH = CH-CO-O-, or -O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; Cou means coumarin-6 -Groups or coumarin-7- groups, and the hydrogen atoms to which they are bonded may each independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo 1, 1 to 5 carbon alkyl groups, or 1 to 5 alkyloxy groups; one of q1 and q2 is 1 and the other is 0; q3 is 0 or 1; P and Q are each independently A group selected from the group consisting of a divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, an alicyclic hydrocarbon having 5 to 8 carbon atoms, and a combination thereof, but X is -CH = CH When -CO-O-, -O-CO-CH = CH-, P or Q on the side to which -CH = CH- is bonded is an aromatic ring. When the number of P is 2 or more, P may be the same as or different from each other. When the number of Q is 2 or more, Q may be the same or different from each other; l1 is 0 or 1; l2 is an integer from 0 to 2; when l1 and 12 are 0, A is a single bond when T is a single bond; When l1 is 1, B is a single bond when T is a single bond; H and I are each independently selected from a divalent benzene ring and naphthalene , Biphenyl ring, a furan ring, a pyrrole ring, and a group of their portfolio.

The side chain may be any photosensitive side chain selected from the group consisting of the following formulae (7) to (10).

In the formula, A, B, D, Y ₁ , X, Y ₂ , and R have the same definitions as above; l represents an integer of 1 to 12; m represents an integer of 0 to 2; m1 and m2 represent 1 to 3; Integer; n represents an integer from 0 to 12 (but B is a single bond when n = 0).

The side chain may be any photosensitive side chain selected from the group consisting of the following formulae (11) to (13).

In the formula, A, X, 1, m, m1, and R have the same definitions as described above.

The side chain may be a photosensitive side chain represented by the following formula (14) or (15).

In the formula, A, Y ₁ , 1, m1 and m2 have the same definitions as above.

The side chain may be a photosensitive side chain represented by the following formula (16) or (17):

In the formula, A, X, l, and m have the same definitions as described above.

The side chain may be a photosensitive side chain represented by the following formula (18) or (19).

In the formula, A, B, Y ₁ , q1, q2, m1 and m2 have the same definitions as above.

R ₁ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, a halogen group, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms Oxygen.

The side chain may be a photosensitive side chain represented by the following formula (20).

In the formula, A, Y ₁ , X, l, and m have the same definitions as above.

In addition, the (A) side chain-type polymer may have any liquid crystal side chain selected from the group consisting of the following formulae (21) to (31).

In the formula, A, B, q1, and q2 have the same definitions as above; Y ₃ is selected from the group consisting of monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, and lipid having 5 to 8 carbon atoms. Cyclic hydrocarbons, and groups of groups of these, the hydrogen atoms bonded to them may each independently pass -NO ₂ , -CN, halo, 1 to 5 carbon alkyl groups, or carbon 1 to 5 alkyloxy substitution; R ₃ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, monovalent benzene ring, naphthalene Ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, alicyclic hydrocarbon having 5 to 8 carbons, alkyl having 1 to 12 carbons, or alkoxy having 1 to 12 carbons; l represents 1 to 12 Integer, m represents an integer from 0 to 2, but in formulas (23) to (24), the total of all m is 2 or more, and in formulas (25) to (26), the total of all m is 1 or more, m1, m2 and m3 each independently represent an integer of 1 to 3; R ₂ represents a hydrogen atom, -NO ₂ , -CN, a halogen group, a monovalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a nitrogen-containing heterocyclic ring, and Alicyclic hydrocarbons having 5 to 8 carbon atoms, and alkyl or alkyloxy groups; Z ₁ and Z ₂ represent single bonds, -CO-, -CH ₂ O-, -CH = N-, -CF _2- .

<< Method for manufacturing photosensitive side chain polymer >>

The said photosensitive side chain type polymer which can exhibit liquid crystallinity can be obtained by superposing | polymerizing the said photoreactive side chain monomer which has a photosensitive side chain, and a liquid crystal side chain monomer.

[Photoreactive side chain monomer]

The photoreactive side chain single system refers to a monomer that can form a polymer having a photosensitive side chain at a side chain portion of the polymer when the polymer is formed.

The photoreactive group in the side chain is preferably the following structure and its derivative.

More specific examples of the photoreactive side chain monomer include, for example, a compound selected from the group consisting of hydrocarbons, (meth) acrylates, itaconic acid esters, fumaric acid esters, maleic acid esters, and α-methylene-γ-butane. Free radical polymerizable groups such as lactone, styrene, ethylene, maleimine, norbornene, and a polymerizable group composed of at least one group of siloxanes, and a polymerizable group composed of the above formula (1) ~ The photosensitive side chain formed by at least one of (6) is preferably, for example, a photosensitive side chain formed by at least one of the above formulae (7) to (10), and a photosensitive side chain formed by the above formulae (11) to (13). ), At least one of the photosensitive side chains, the photosensitive side chain represented by the above formula (14) or (15), the photosensitive side chain represented by the above formula (16) or (17), the above formula ( The structure of the photosensitive side chain represented by 18) or (19) and the photosensitive side chain represented by the above formula (20) is preferable.

This case is provided as a photoreactive and / or liquid crystalline side chain monomer, for example, novel compounds (1) to (11) represented by the following formulae (1) to (11); and represented by the following formulae (12) to (17) Compounds (12) to (17).

In the formula, R represents a hydrogen atom or a methyl group; S represents an alkylene group having 2 to 10 carbon atoms; R ¹⁰ represents Br or CN; S represents an alkylene group having 2 to 10 carbon atoms; u represents 0 or 1; and Py Represents 2-pyridyl, 3-pyridyl, or 4-pyridyl; and v represents 1 or 2.

[Liquid crystal side chain monomer]

The so-called liquid crystal side chain single system refers to a polymer developing liquid derived from the monomer It is crystalline, and the polymer can form a liquid crystal-based (Mesogen) monomer at a side chain portion.

The liquid crystal group in the side chain may be a group that becomes a liquid crystal group structure alone, such as biphenyl or phenyl benzoate, or a group such as benzoic acid, in which side chains are hydrogen bonded to each other to form a liquid crystal group structure. The liquid crystal group of the side chain preferably has the following structure.

More specific examples of the liquid crystalline side chain monomer are preferably those selected from the group consisting of hydrocarbons, (meth) acrylates, itaconic acid esters, fumaric acid esters, maleic acid esters, and α-methylene-γ- Free-radically polymerizable groups such as butyrolactone, styrene, ethylene, maleimide, norbornene, and a polymerizable group composed of at least one group of siloxanes, and a polymerizable group composed of the above formula (21) The structure of the side chain formed by at least one of ~ (31) is preferable.

(A) A side chain polymer can exhibit liquid crystal properties by the above It is obtained by polymerization of a photoreactive side chain monomer. In addition, it is possible to copolymerize a photoreactive side chain monomer and a liquid crystalline side chain monomer that do not exhibit liquid crystallinity, or a copolymerization of a photoreactive side chain monomer and a liquid crystal side chain monomer that exhibit liquid crystallinity. And get. Furthermore, it can be copolymerized with other monomers within a range that does not impair liquid crystal display performance.

Other monomers are exemplified by freely polymerizable monomers which are commercially available.

Specific examples of other monomers include unsaturated carboxylic acids, acrylate compounds, methacrylate compounds, maleimide compounds, acrylonitrile, maleic anhydride, styrene compounds, and ethylene compounds.

Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid.

Examples of the acrylate compound include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthracene acrylate, anthryl methyl acrylate, phenyl acrylate, and 2,2,2-trifluoroacrylate Ethyl ester, tert-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydroacrylic acid Furfuryl ester, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, and acrylic acid 8-ethyl-8-tricyclodecyl ester and the like.

Examples of methacrylate compounds include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthracene methacrylate, and anthracene methacrylate Methyl ester, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, third butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, methacrylic acid 2 -Methoxyethyl, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, methyl 2-methyl-2-adamantyl methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and 8-ethyl methacrylate -8-tricyclodecyl ester and the like. Also available are glycidyl (meth) acrylate, (3-methyl-3-oxetanyl) methyl (meth) acrylate, and (3-ethyl-3-oxelan) (meth) acrylate (Meth) acrylate compounds having a cyclic ether group such as butyl) methyl ester.

Examples of the vinyl compound include vinyl ether, methyl vinyl ether, benzyl vinyl ether, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and propyl vinyl ether.

Examples of the styrene compound include styrene, methylstyrene, chlorostyrene, and bromostyrene.

Examples of the maleimide compound include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

The manufacturing method of the side chain polymer in this embodiment is not particularly limited, and a method widely used in industry can be used. Specifically, it can manufacture by cationic polymerization, radical polymerization, and anionic polymerization of the vinyl group of a liquid crystal side chain monomer or a photoreactive side chain monomer. Among these, a radical polymerization is particularly preferable from the viewpoint of easy reaction control.

As the polymerization initiator for the radical polymerization, conventional compounds such as a radical polymerization initiator, a reversible addition-broken chain transfer (RAFT) polymerization reagent, and the like can be used.

A radical thermal polymerization initiator is a compound that generates a radical by heating above a decomposition temperature. Examples of such a radical thermal polymerization initiator include ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, and the like), and difluorenyl peroxides (ethyl fluorenyl peroxide) , Benzamyl peroxide, etc.), peroxides (hydrogen peroxide, third butyl hydrogen peroxide, cumene hydrogen peroxide, etc.), dialkyl peroxides (di-third Peroxides, dicumyl peroxide, dilauryl peroxide, etc.), peroxyketals (dibutylperoxycyclohexane, etc.), alkylperesters (peroxy Tert-butyl neodecanoate, tert-butyl peroxypivalate, tert-peroxy 2-ethylcyclohexanoate, etc.), persulfates (potassium persulfate, sodium persulfate, Ammonium persulfate, etc.), azo compounds (azobisisobutyronitrile, 2,2'-bis (2-hydroxyethyl) azobisisobutyronitrile, etc.). Such a radical thermal polymerization initiator may be used individually by 1 type, and may be used in combination of 2 or more type.

The radical photopolymerization initiator is not particularly limited as long as it is a compound that initiates radical polymerization by irradiation with light. Examples of such a radical photopolymerization initiator include benzophenone, Michler's ketone, 4,4'-bis (diethylamino) benzophenone, xanthone, thioxanthone, isopropyl Propyl xanthone, 2,4-diethylthioxanthone, 2-ethylanthraquinone, acetophenone, 2-hydroxy-2-methylphenylacetone, 2-hydroxy-2-methyl-4 ' -Cumyl acetone, 1-hydroxycyclohexyl phenyl ketone, cumene benzoin ether, isobutyl benzoin ether, 2,2-diethoxy Acetophenone, 2,2-dimethoxy-2-phenylacetophenone, camphorquinone, benzanthrone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholinylpropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinylphenyl) -butanone-1, 4-dimethylaminobenzoic acid Ethyl ester, 4-dimethylaminoisobenzoate, 4,4'-bis (third butylperoxycarbonyl) benzophenone, 3,4,4'-tris (third butyl peroxy) (Oxycarbonyl) benzophenone, 2,4,6-trimethylbenzylidenediphenylphosphine oxide, 2- (4'-methoxystyryl) -4,6-bis (trichloro (Methyl) -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 (tri (Chloromethyl) -s-triazine, 2- (4'-pentoxystyryl) -4,6-bis (trichloromethyl) -s-triazine, 4- [p-N, N- Bis (ethoxycarbonylmethyl)]-2,6-bis (trichloromethyl) -s-triazine, 1,3-bis (trichloromethyl) -5- (2'-chlorophenyl)- s-triazine, 1,3-bis (trichloromethyl) -5- (4'-methoxyphenyl) -s-triazine, 2- (p-dimethylaminostyryl) benzo Oxazole, 2- (p- Dimethylaminostyryl) benzothiazole, 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'-methyl (4-ethoxy (Carbonylphenyl) -1,2'-biimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5'-tetraphenyl-1,2'-bi Imidazole, 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-dimethylaminopropylamido) Carbazole, 3,6-bis (2-methyl-2-morpholinylpropionyl) -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'-tetrakis (third butylperoxycarbonyl) benzophenone, 3,3 ', 4,4'-tetrakis (third hexylperoxycarbonyl) benzophenone, 3,3'-di (Methoxycarbonyl) -4,4'-bis (third butylperoxycarbonyl) benzophenone, 3,4'-bis (methoxycarbonyl) -4,3'-bis (third butyl Peroxycarbonyl) benzophenone, 4,4'-bis (methoxycarbonyl) -3,3'-bis (third butylperoxycarbonyl) benzophenone, 2- (3-methyl -3H-benzothiazole-2-ylidene) -1-naphthyl-2-yl-ethanone, or 2- (3-methyl-1,3-benzothiazole-2 (3H) -ylidene)- 1- (2-benzylidene) ethanone and the like. These compounds may be used alone or in combination of two or more.

The radical polymerization method is not particularly limited, and an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, a precipitation polymerization method, a block polymerization method, a solution polymerization method, and the like can be used.

The organic solvent used in the polymerization reaction of the photosensitive side chain polymer that can exhibit liquid crystallinity is not particularly limited as long as it can dissolve the produced polymer. Specific examples are listed below.

N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone (Pyrrolidone), N-ethyl-2-pyrrolidone, N-methylcaprolactone Amine, dimethyl sulfene, tetramethyl urea, pyridine, dimethyl fluorene, hexamethyl fluorene, γ-butyrolactone, isopropanol, methoxymethylpentanol, dipentene, ethyl Amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl lysone, ethyl lysone, methyl lysone acetate , Ethyl lysone acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethyl acetate Glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol third butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol Ethylene glycol dimethyl 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, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, N-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethyl carbonate, propyl carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate , Propylene glycol acetate monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxy Propionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentyl Ketones, 3-methoxy-N, N-dimethylpropanamide, 3-ethoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropane Amidine and so on.

These organic solvents may be used alone or in combination. Moreover, even if it is a solvent which does not dissolve the produced | generated polymer, in the range which the produced | generated polymer does not precipitate, it can mix and use in the said organic solvent.

In addition, in radical polymerization, oxygen in an organic solvent becomes a cause of hindering the polymerization reaction. Therefore, it is preferable that the organic solvent is degassed as much as possible.

The polymerization temperature at the time of radical polymerization may be selected from any temperature of 30 ° C to 150 ° C, but is preferably in the range of 50 ° C to 100 ° C. In addition, the reaction It can be carried out at any concentration, but when the concentration is too low, it is difficult to obtain a polymer with a high molecular weight. When the concentration is too high, the viscosity of the reaction liquid becomes too high and it is difficult to uniformly stir. %, More preferably 5 mass% to 30 mass%. The reaction is carried out at a high concentration in the initial stage, and then an organic solvent may be added.

In the above-mentioned radical polymerization reaction, when the ratio of the radical polymerization initiator is larger than that of the monomer, the molecular weight of the obtained polymer becomes smaller, and when the ratio is smaller, the molecular weight of the obtained polymer becomes larger. The ratio is preferably 0.1 mol% to 10 mol% relative to the monomer to be polymerized. During the polymerization, various monomer components, solvents, and initiators may be added.

[Recycling of polymers]

When the polymer produced is recovered from the reaction solution of the photosensitive side-chain polymer exhibiting liquid crystallinity obtained by the above reaction, the reaction solution may be put into a weak solvent to precipitate these polymers. Examples of the weak solvent used for precipitation include methanol, acetone, hexane, heptane, butylcellolysin, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, diethyl ether, methyl alcohol Ethyl ether, water, etc. The precipitated polymer is put into a weak solvent, and after filtering and recovering, the polymer can be dried under normal pressure or reduced pressure at normal temperature or under heating. In addition, when the polymer recovered by precipitation is re-dissolved in an organic solvent, and the operation of re-precipitation recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the weak solvent at this time include alcohols, ketones, hydrocarbons, and the like. When three or more weak solvents selected from these are used, it is preferable to improve the purification efficiency.

When the molecular weight of the (A) side chain polymer of the present invention takes into consideration the strength of the obtained coating film, workability during coating film formation, and uniformity of the coating film, the weight average molecular weight measured by GPC (gel permeation chromatography) method It is preferably 2,000 to 1,000,000, and more preferably 5,000 to 100,000.

[Modulation of polymer composition]

The polymer composition used in the present invention is preferably a coating liquid suitable for forming a liquid crystal alignment film. That is, the polymer composition used in the present invention is preferably prepared in the form of a solution in which a resin component for forming a resin film is dissolved in an organic solvent. Here, this resin component is a resin component containing the photosensitive side chain type polymer which can demonstrate liquid crystallinity demonstrated previously. At this time, the content of the resin component is preferably 1% to 20% by mass, more preferably 3% to 15% by mass, and particularly preferably 3% to 10% by mass.

In the polymer composition of this embodiment, all of the aforementioned resin components may be photosensitive side-chain polymers capable of exhibiting liquid crystallinity, but they may be mixed within a range that does not impair liquid crystal display performance and photosensitivity. Other polymers than. At this time, the content of other polymers in the resin component is 0.5% by mass to 80% by mass, and preferably 1% by mass to 50% by mass.

Examples of such other polymers include polymers composed of poly (meth) acrylate, polyamic acid, polyimide, and the like, which are not photosensitive side-chain polymers that exhibit liquid crystallinity.

<< (B) Organic solvents >>

As long as the organic solvent used in the polymer composition used in the present invention is The organic solvent in which the resin component is dissolved is not particularly limited. Specific examples are listed below.

N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl sulfene, tetramethylurea, pyridine, dimethyl fluorene, hexamethyl fluorene, γ-butyrolactone, 3-methoxy-N, N-dimethylpropane Pyridamine, 3-ethoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropanamide, 1,3-dimethyl-imidazolinone, ethyl Pentyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethyl acetate, propylene carbonate, diglyme Ether, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol third butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol Alcohol monoacetate, diethylene glycol dimethyl 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, three Glycol methyl ether. These can be used alone or in combination.

The polymer composition used in the present invention may contain components other than the components (A) and (B) described above. Examples include solvents or compounds that improve film thickness uniformity or surface smoothness when coating a polymer composition, compounds that improve adhesion between a liquid crystal alignment film and a substrate, and the like, but are not limited thereto.

Specific examples of the solvent (weak solvent) for improving film thickness uniformity or surface smoothness are listed below.

For example, isopropanol, methoxymethylpentanol, methyl lysin, ethyl lysin, butyl lysin, methyl lysin acetate, ethyl lysin acetate, butyl card Alcohol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol Monoacetate, propylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, propylene glycol third butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol Dimethyl 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, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, 1-hexanol, n-hexane , N-pentane, n-octane , Diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, 3-methoxypropyl Methyl ester, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propionate Ester, 3-methoxypropanoate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy 2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol , 2- (2-ethoxypropoxy) propanol, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate and other organic solvents with low surface tension.

These weak solvents may be used singly or in combination. When using a solvent as described above, avoiding a significant decrease in the solubility of the solvent contained in the polymer composition as a whole, preferably 5 to 80% by mass of the entire solvent, and more preferably 20 to 60% by mass.

Compounds that improve the uniformity of the film thickness or surface smoothness include, for example, fluorine-based surfactants, silicone-based surfactants, and non-ionic surfactants.

More specifically, there are, for example, EF TOP (registered trademark) 301, EF303, EF352 (manufactured by TOHKEM PRODUCTS), MEGAFAC (registered trademark) F171, F173, R-30 (manufactured by DIC), Fluorad FC430, FC431 (Sumitomo 3M Company), ASAHI GUARD (registered trademark) AG710 (manufactured by Asahi Glass Co., Ltd.), SURFLON (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC Seimi Chemical), and the like. The use ratio of these surfactants is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass relative to 100 parts by mass of the resin component contained in the polymer composition.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include, for example, the following compounds containing a functional silane.

Examples include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropane Trimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl 3-Aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylene triamine, N -Trimethoxysilylpropyltriethylene triamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7- Triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl acetate 3-Aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl -3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyl Triethoxysilane and so on.

In addition, in addition to improving the adhesion between the substrate and the liquid crystal alignment film, in order to prevent the decrease in electrical characteristics caused by the backlight when constituting a liquid crystal display element, the polymer composition may contain a phenoplast system such as the following Or additives to epoxy-containing compounds. Although the specific phenolic plastic additive is shown below, it is not limited to this structure.

Specific epoxy-containing compounds include, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and propylene glycol diglycidyl ether. Oil ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo Neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylene Amine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenyl Methane, etc.

When using a compound that improves the adhesion to the substrate, the amount used is 100 parts by mass relative to the resin component contained in the polymer composition, preferably 0.1 to 30 parts by mass, and more preferably 1 part by mass to 20 parts by mass. When the amount is less than 0.1 parts by mass, the effect of improving adhesion cannot be expected, and when the amount is more than 30 parts by mass, the alignment of the liquid crystal may be deteriorated.

Additives can also use photosensitizers. Colorless sensitizers and triplet sensitizers are preferred.

Photosensitizers include aromatic nitro compounds, coumarin (7-diethylamino-4-methylcoumarin, 7-hydroxy-4-methylcoumarin), ketocoumarin, and carbonyl Dicoumarin, aromatic 2-hydroxy ketones, and aromatic 2-hydroxy ketones (2-hydroxybenzophenone, mono- or di-p- (dimethylamino) -2-hydroxy Benzophenone), acetophenone, anthraquinone, xanthone, thioxanthone, benzoxanthone, thiazoline (2-benzylidenemethylene-3-methyl-β-naphthothiazoline , 2- (β-naphthoyl methylene) -3-methylbenzothiazoline, 2- (α-naphthoylmethylene) -3-methylbenzothiazoline, 2- (4-Bisphenolmethylene) -3-methylbenzothiazoline, 2- (β-naphthylmethylene) -3-methyl-β-naphthylthiazoline, 2- (4-Biphenoyl methylene) -3-methyl-β-naphthylthiazoline, 2- (p-fluoro Benzamidinemethylene) -3-methyl-β-naphthylthiazoline), oxazoline (2-benzylmethylene-3-methyl-β-naphthyloxazoline, 2 -(β-naphthylmethylene) -3-methylbenzoxazoline, 2- (α-naphthylmethylene) -3-methylbenzoxazoline, 2- ( 4-Bisphenolmethylene) -3-methylbenzoxazoline, 2- (β-naphthylmethylene) -3-methyl-β-naphthoxazoline, 2- ( 4-Bisphenolmethylene) -3-methyl-β-naphthoxazoline, 2- (p-fluorobenzylidenemethylene) -3-methyl-β-naphthooxazoline ), Benzothiazole, nitroaniline (m- or p-nitroaniline, 2,4,6-trinitroaniline) or nitropinene (5-nitropinene), (2-[(m -Hydroxy-p-methoxy) styryl] benzothiazole, benzoin alkyl ether, N-alkylated phthalone, acetophenone ketal (2,2-dimethoxybenzene Methyl ethyl ketone), naphthalene, anthracene (2-naphthalenemethanol, 2-naphthalenecarboxylic acid, 9-anthracene methanol, and 9-anthracenecarboxylic acid), benzopyran, azoindole, furan coumarin, and the like.

Preferred are aromatic 2-hydroxyketone (benzophenone), coumarin, ketocoumarin, carbonylbiscoumarin, acetophenone, anthraquinone, xanthone, thioxanthone and acetophenone. ketone.

In addition to the above, in the polymer composition, as long as the range of the effect of the present invention is not impaired, a dielectric body or a conductive material may be added to change the electrical properties such as the permittivity or conductivity of the liquid crystal alignment film. The cross-linking compound is used to improve the film hardness or density when forming a liquid crystal alignment film.

The method of applying the polymer composition to a substrate having a conductive film for lateral electric field driving is not particularly limited.

The coating method is generally industrially performed by screen printing, lithography, flexographic printing, or inkjet. Other coating methods are dipping method, A roll coating method, a slit coating method, a spin coating method (spin coating method), or a spray method can be used depending on the purpose.

After the polymer composition is coated on a substrate having a conductive film for lateral electric field drive, heating means such as a hot plate, a thermal cycle oven, or an IR (infrared) oven can be used at 50 to 200 ° C, preferably 50 The coating film was obtained by evaporating the solvent at ~ 150 ° C. The drying temperature at this time is preferably lower than the liquid crystal phase development temperature of the side chain polymer.

When the thickness of the coating film is too thick, the power consumption of the liquid crystal display element becomes unfavorable. When the thickness is too thin, the reliability of the liquid crystal display element may be reduced. Therefore, it is preferably 5 nm to 300 nm, and more preferably 10 nm to 150 nm.

After the step [I], and before the step [II], a step of cooling the substrate on which the coating film is formed to room temperature may be provided.

<Step [II]>

Step [II] is irradiating the coating film obtained in step [I] with polarized ultraviolet rays. When the film surface of the coating film is irradiated with polarized ultraviolet rays, the substrate is irradiated with polarized ultraviolet rays through a polarizing plate from a certain direction. The ultraviolet rays used can be ultraviolet rays with a wavelength ranging from 100nm to 400nm. It is preferable to select the most appropriate wavelength according to the type of coating film used, the transparent filter, and the like. In addition, for example, ultraviolet light in a range of 290 nm to 400 nm can be selected to selectively induce a photo-crosslinking reaction. As the ultraviolet rays, for example, light emitted from a high-pressure mercury lamp can be used.

The amount of polarized ultraviolet radiation depends on the coating film used. The amount of irradiation is to achieve the difference between the absorbance of ultraviolet light in the direction parallel to the polarized light's polarized light direction in the coating film and the absorbance of ultraviolet light in the vertical direction. That is, the maximum value of ΔA (hereinafter also referred to as ΔAmax) is preferably within a range of 1% to 70% of the amount of polarized ultraviolet rays, and more preferably within a range of 1% to 50%.

<Step [III]>

Step [III] is to heat the coating film irradiated with polarized ultraviolet rays in step [II]. By heating, an alignment control ability can be given to a coating film.

For heating, heating means such as a hot plate, a thermal cycle type oven, or an IR (infrared) type oven can be used. The heating temperature can be determined in consideration of the temperature at which the coating film used exhibits liquid crystallinity.

The heating temperature is preferably within a temperature range of a temperature at which the side chain polymer exhibits liquid crystallinity (hereinafter referred to as a liquid crystal exhibiting temperature). For example, when the film surface of the coating film is used, the liquid crystal display temperature of the coating film surface is estimated to be lower than the liquid crystal display temperature of the photosensitive side chain polymer that exhibits liquid crystal properties as a whole. Therefore, the heating temperature is more preferably within the temperature range of the liquid crystal display temperature on the surface of the coating film. That is, the temperature range of the heating temperature after the irradiation of polarized ultraviolet light is set to a lower limit of a temperature lower than the lower limit of the temperature range of the liquid crystal display temperature of the side chain polymer used by the lower limit, and lower than the upper limit of the liquid crystal temperature range by 10 ° C It is preferable that the temperature is in the range of the upper limit. When the heating temperature is lower than the above temperature range, there is a tendency that the effect of anisotropic amplification by heat in the coating film is insufficient, and when the heating temperature is too higher than the above temperature range, the state of the coating film is close to isotropic. The liquid state (isotropic phase) tends to be difficult to align in one direction by self-organization.

In addition, the liquid crystal display temperature refers to a glass transition temperature (Tg) or higher when the side chain polymer or the surface of the coating film is transferred from the solid phase to the liquid crystal phase. Generated from the liquid crystal phase to a temperature below the isotropic phase (isotropic phase) isotropic phase transition temperature (Tiso).

The thickness of the coating film formed after heating is the same as that described in step [I], and is preferably 5 nm to 300 nm, and more preferably 50 nm to 150 nm.

<Step [IV]>

Step [IV] is to cool the coating film heated in step [III] to a temperature below the glass transition temperature of the surface of the coating film, and then heat it to a temperature above the glass transition temperature.

That is, the coating film obtained by heating in step [III] is once cooled to a temperature that does not reach the glass transition temperature of the coating film surface. In other words, by cooling the coating film obtained in the step [III] to a temperature lower than the lower limit of the liquid crystal development temperature of the coating film surface, the liquid crystal state phase of the coating film surface is transferred to a solid state (glass transfer). Here, the cooling temperature of the coating film, in which the liquid crystal display temperature on the surface of the coating film tends to be lower than the liquid crystal display temperature when the side chain polymer is viewed as a whole, is therefore more than the glass transition of the side chain polymer of the component (A) A temperature lower than the point temperature (Tg) by 10 ° C or more is preferred. A preferred example of this cooling temperature is room temperature (for example, 25 ° C).

The cooling of the coating film obtained by heating in step [III] uses a cooling chamber or a cooling material to actively cool to the intended cooling temperature, but it can also be taken out by heating means and left to cool slowly.

Step [IV] is to heat the cooled coating film to a temperature above the glass transition temperature of the coating film surface. Specifically, after cooling the coating film, Heating to the liquid crystal display temperature of the coating film surface. As mentioned above, the liquid crystal display temperature on the surface of the coating film refers to a temperature above the glass transition temperature of the coating film surface and not reaching the isotropic phase transition temperature on the surface of the coating film. The heating temperature (heating temperature of step [III]) of the coating film after polarized ultraviolet irradiation and the heating temperature during reheating after cooling may be the same or different, but the heating temperature during reheating is preferably after polarized ultraviolet irradiation The temperature below the heating temperature of the coating film.

By having the above steps, the manufacturing method of the present invention can achieve an efficient introduction of anisotropy into a coating film. Moreover, a substrate with a liquid crystal alignment film can be manufactured with high efficiency.

<Step [V]>

The step [V] is to make the substrate (the first substrate) having a liquid crystal alignment film on the conductive film for lateral electric field driving obtained in [IV], in the same manner as in the above-mentioned [I '] to [III'] or step [ The substrate (second substrate) with a liquid crystal alignment film without a conductive film obtained from I '] ~ [IV'] is arranged in an opposing manner through the liquid crystal so that the liquid crystal alignment films of the two are opposed to each other. A liquid crystal cell to produce a lateral electric field drive type liquid crystal display element. In addition, in step [I '] to [III'] or step [I '] to [IV'], a substrate having no conductive film for lateral electric field driving is used instead of step [I], and the substrate has conductive for lateral electric field driving. Except for the substrate of the film, it can be performed in the same manner as steps [I] to [III] or steps [I '] to [IV']. The difference between steps [I] to [IV] and steps [I '] to [IV'] is only the presence or absence of the above-mentioned conductive film, so the description of steps [I '] to [IV'] is omitted.

When exemplifying the production of a liquid crystal cell or a liquid crystal display element, The method of preparing the above first and second substrates, and spreading the spacers on the liquid crystal alignment film of one of the substrates so that the liquid crystal alignment film surface becomes the inside, bonding the other substrate, injecting liquid crystal under reduced pressure, and sealing, Alternatively, after the liquid crystal is dropped on the surface of the liquid crystal alignment film on which the spacers are dispersed, the substrate is bonded and sealed. At this time, one of the substrates is preferably a substrate using an electrode having a comb-like structure for driving a lateral electric field. The diameter of the spacer at this time is preferably 1 μm to 30 μm, and more preferably 2 μm to 10 μm. The diameter of the spacer determines the distance between a pair of substrates sandwiching the liquid crystal layer, that is, the thickness of the liquid crystal layer.

The method for producing a substrate with a coating film of the present invention is to apply a polymer composition on a substrate to form a coating film, and then irradiate polarized ultraviolet rays. Next, introduction of an anisotropy into the side-chain polymer film with high efficiency is achieved by heating, and a substrate with a liquid crystal alignment film having alignment control ability of liquid crystal is manufactured.

The coating film used in the present invention utilizes the principle of molecular realignment caused by the photoreaction based on side chains and the self-organization of liquid crystallinity to achieve the introduction of high-efficiency anisotropy to the coating film. In the manufacturing method of the present invention, when the side chain polymer has a photo-crosslinkable group structure as a photoreactive group, the side chain polymer is used to form a coating film on a substrate, and then irradiated with polarized ultraviolet rays, followed by heating Production of a liquid crystal display device.

In the following description, an embodiment using a side chain polymer having a structure having a photo-crosslinkable group as a photoreactive group is referred to as a first form, and using a light Fries rearrangement group as a photoreactive group may cause a difference. An embodiment of the structured side chain polymer is called a second embodiment.

FIG. 1 schematically illustrates anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film using a side chain polymer having a structure having a photo-crosslinkable group as a photoreactive group in the first aspect of the present invention. Illustration of an example. FIG. 1 (a) is a diagram schematically showing a state of a side chain polymer film before polarized light irradiation, and FIG. 1 (b) is a diagram schematically showing a state of a side chain polymer film after polarized light irradiation, FIG. 1 (c ) Is a diagram schematically showing the state of the side chain polymer film after heating, especially when the anisotropy introduced is small, that is, in the first aspect of the present invention, the amount of ultraviolet radiation in step [II] is Schematic diagram when ΔA is in the range of 1% to 15% of the maximum ultraviolet exposure.

FIG. 2 schematically illustrates anisotropic introduction processing in a method for manufacturing a liquid crystal alignment film using a side chain polymer having a structure having a photo-crosslinkable group as a photoreactive group in the first aspect of the present invention. Illustration of an example. FIG. 2 (a) is a diagram schematically showing a state of a side chain type polymer film before polarized light irradiation, FIG. 2 (b) is a diagram schematically showing a state of a side chain type polymer film after polarized light irradiation, and FIG. 2 (c ) Is a diagram schematically showing the state of the side chain polymer film after heating, especially when the anisotropy is large, that is, in the first aspect of the present invention, the amount of ultraviolet radiation in step [II] is ΔA. It is a schematic diagram when it is within the range of 15% to 70% of the maximum ultraviolet exposure.

FIG. 3 is a side-chain structure schematically illustrating a structure using a photo-isomerizable group or a light Fries rearrangement group represented by the above formula (18) as a photo-reactive group in the second aspect of the present invention. An example of an anisotropic introduction process in a method for manufacturing a polymer liquid crystal alignment film. image 3 (a) is a diagram schematically showing the state of the side chain polymer film before polarized light irradiation, FIG. 3 (b) is a diagram schematically showing the state of the side chain polymer film after polarized light irradiation, FIG. 3 (c) is a diagram A diagram schematically showing the state of the side chain polymer film after heating, especially when the anisotropy introduced is small, that is, in the second aspect of the present invention, the ultraviolet irradiation amount ΔA in the step [II] is the maximum Schematic diagram when the ultraviolet irradiation amount is within the range of 1% to 70%.

FIG. 4 schematically illustrates the manufacture of a liquid crystal alignment film using a side chain polymer having a structure having a light Fries rearrangement group represented by the above formula (19) as a photoreactive group in the second aspect of the present invention. An example of anisotropic import processing in the method. FIG. 4 (a) is a diagram schematically showing a state of a side chain type polymer film before polarized light irradiation, FIG. 4 (b) is a diagram schematically showing a state of a side chain type polymer film after polarized light irradiation, and FIG. 4 (c ) Is a diagram schematically showing the state of the side chain polymer film after heating, especially when the anisotropy is large, that is, in the second aspect of the present invention, the ultraviolet irradiation amount in step [II] is ΔA It is a schematic diagram when it is within the range of 1% to 70% of the maximum ultraviolet exposure.

In the first aspect of the present invention, in the anisotropic introduction process for the coating film, when the ultraviolet irradiation amount in the step [II] is within a range of 1% to 15% of the maximum ultraviolet irradiation amount in which ΔA is the maximum, first, in A coating film 1 is formed on the substrate. As shown in FIG. 1 (a), the coating film 1 formed on the substrate has a structure in which side chains 2 are randomly arranged. According to the random arrangement of the side chains 2 of the coating film 1, the liquid crystal components and the photosensitive groups of the side chains 2 are also randomly aligned, and the coating film 1 is isotropic.

In the first aspect of the present invention, anisotropic introduction to a coating film In the process, when the ultraviolet irradiation amount in the step [II] is in the range of 15% to 70% of the maximum ultraviolet irradiation amount in which ΔA is the maximum, the coating film 3 is first formed on the substrate. As shown in FIG. 2 (a), the coating film 3 formed on the substrate has a structure in which side chains 4 are randomly arranged. According to the random arrangement of the side chains 4 of the coating film 3, the liquid crystal components and photosensitive groups of the side chains 4 are also randomly aligned, and the coating film 2 is isotropic.

In the second aspect of the present invention, in the anisotropic introduction process for the coating film, a side chain using a structure having a photoisomerizable group or a light Fries rearrangement group represented by the above formula (18) is used. In the case of the liquid crystal alignment film of the polymer type, when the ultraviolet irradiation amount in the step [II] is within a range of 1% to 70% of the maximum ultraviolet irradiation amount, ΔA is first formed on the substrate 5. As shown in FIG. 3 (a), the coating film 5 formed on the substrate has a structure in which side chains 6 are randomly arranged. According to the random arrangement of the side chains 6 of the coating film 5, the liquid crystal components and the photosensitive groups of the side chains 6 are also randomly aligned, and the side chain polymer film 5 is isotropic.

In the second aspect of the present invention, in the anisotropic introduction process for the coating film, when a liquid crystal alignment film using a side chain polymer having a structure having a light Fries rearrangement group represented by the above formula (19) is used When the ultraviolet irradiation amount in the step [II] is in the range of 1% to 70% of the maximum ultraviolet irradiation amount in which ΔA is the maximum, first, a coating film 7 is formed on the substrate. As shown in FIG. 4 (a), the coating film 7 formed on the substrate has a structure in which side chains 8 are randomly arranged. According to the random arrangement of the side chains 8 of the coating film 7, the liquid crystal components and the photosensitive groups of the side chains 8 are also randomly aligned, and the coating film 7 is isotropic.

In the first embodiment of the present embodiment, the ultraviolet irradiation in step [II] When the amount is within a range of 1% to 15% of the maximum ultraviolet irradiation amount, ΔA is irradiated with polarized ultraviolet rays to the isotropic coating film 1. That is, as shown in FIG. 1 (b), the photosensitive group of the side chain 2a having a photosensitive group in the side chain 2 arranged in a direction parallel to the polarization direction of the ultraviolet rays causes a photoreaction such as a dimerization reaction preferentially. . As a result, the density of the side chains 2a subjected to the photoreaction becomes slightly higher in the direction of polarized light irradiated with ultraviolet rays, and as a result, the coating film 1 is imparted with very little anisotropy.

In the first aspect of the present embodiment, when the ultraviolet irradiation amount in the step [II] is within a range of 15% to 70% of the maximum ultraviolet irradiation amount, ΔA is irradiated with polarized ultraviolet rays on the isotropic coating film 3 . As a result, as shown in FIG. 2 (b), the photosensitive group of the side chain 4a having a photosensitive group in the side chain 4 arranged in a direction parallel to the polarization direction of the ultraviolet rays preferentially caused a photoreaction such as a dimerization reaction. As a result, the density of the side chains 4a undergoing photoreaction becomes slightly higher in the direction of polarized light irradiated with ultraviolet rays, and as a result, a small anisotropy is imparted to the coating film 3.

In the second aspect of this embodiment, a liquid crystal alignment film using a side chain polymer having a structure having a photoisomerizable group or a light Fries rearrangement group represented by the above formula (18) is used, [II] When the ultraviolet irradiation amount in the step is within a range of 1% to 70% of the maximum ultraviolet irradiation amount, the isotropic coating film 5 is irradiated with polarized ultraviolet rays. As a result, as shown in FIG. 3 (b), the photosensitive group of the side chain 6a having a photosensitive group in the side chain 6 arranged in a direction parallel to the polarization direction of the ultraviolet rays preferentially causes light reactions such as light Fries rearrangement. . As a result, the density of the side chain 6a subjected to the photoreaction became slightly higher in the direction of polarized light irradiated with ultraviolet rays. 5 imparts very little anisotropy.

In the second aspect of the present embodiment, a coating film using a side chain polymer having a structure having a light Fryes rearrangement base represented by the above formula (19) is used, and the ultraviolet irradiation amount in step [II] is such that ΔA is When the maximum ultraviolet irradiation amount is within a range of 1% to 70%, the isotropic coating film 7 is irradiated with polarized ultraviolet rays. As a result, as shown in FIG. 4 (b), the photosensitive groups of the side chains 8a having the photosensitive groups in the side chains 8 arranged in a direction parallel to the polarization direction of the ultraviolet rays preferentially cause light reactions such as light Fries rearrangement. . As a result, the density of the side chains 8a subjected to the photoreaction becomes higher in the polarization direction of the ultraviolet rays, and as a result, a small anisotropy is imparted to the coating film 7.

Next, in the first aspect of the present embodiment, when the amount of ultraviolet irradiation in step [II] is within a range of 1% to 15% of the maximum amount of ultraviolet irradiation at ΔA, the coating film 1 after the polarized light irradiation is heated to become LCD status. As a result, as shown in FIG. 1 (c), the coating film 1 differed in the amount of cross-linking reaction between the direction parallel to and perpendicular to the direction of polarized light irradiated with ultraviolet rays. In this case, since the amount of cross-linking reaction generated in a direction parallel to the direction of polarized light irradiated with ultraviolet rays is very small, the cross-linking reaction site functions as a plasticizer. Therefore, the liquid crystallinity in the direction perpendicular to the direction of polarized light irradiated with ultraviolet rays is higher than the liquid crystallinity in the parallel direction, and self-organized in a direction parallel to the direction of polarized light irradiated with ultraviolet rays to reorient the side chain 2 containing the liquid crystal component. As a result, the extremely small anisotropy of the coating film 1 caused by the photo-crosslinking reaction is increased by heat, and a greater anisotropy is imparted to the coating film 1.

Similarly, in the first aspect of the present embodiment, the amount of ultraviolet irradiation in step [II] is 15% to 70% of the maximum amount of ultraviolet irradiation in which ΔA is the maximum. When it is within the range, the coating film 3 after the polarized light irradiation is heated to be in a liquid crystal state. As a result, as shown in FIG. 2 (c), the amount of cross-linking reaction between the side chain polymer film 3 and the direction parallel to the direction of polarized light irradiated with ultraviolet rays is different. Therefore, self-organization is performed in a direction parallel to the direction of polarized light irradiated with ultraviolet rays to realign the side chain 4 containing the liquid crystal component. As a result, the small anisotropy of the coating film 3 caused by the photo-crosslinking reaction is increased by heat, and a larger anisotropy is imparted to the coating film 3.

Similarly, in the second aspect of this embodiment, a coating film of a side chain polymer using a structure having a photo-isomerizable group or a light Fryes rearrangement group represented by the above formula (18) is used. II] When the ultraviolet irradiation amount in the step is within a range of 1% to 70% of the maximum ultraviolet irradiation amount, ΔA is heated, and the coating film 5 after polarized light irradiation is heated to become a liquid crystal state. As a result, as shown in FIG. 3 (c), the coating film 5 has different amounts of Fryce rearrangement reactions between the parallel and vertical directions of the polarized light direction irradiated with ultraviolet rays. In this case, the liquid crystal alignment force of the Frye rearrangement which is generated in a direction perpendicular to the polarized light direction irradiated with ultraviolet rays is stronger than the liquid crystal alignment force of the side chain before the reaction. Self-organizing causes the side chain 6 containing the liquid crystal component to re-align. As a result, the very small anisotropy of the coating film 5 caused by the Fries rearrangement reaction is increased due to heat, and a greater anisotropy is imparted to the coating film 5.

Similarly, in the second aspect of the present embodiment, a coating film using a side chain polymer having a structure having a light Fries rearrangement group represented by the above formula (19) is used, and the amount of ultraviolet radiation in step [II] When ΔA is within the range of 1% to 70% of the maximum ultraviolet irradiation amount, polarized light is irradiated The subsequent coating film 7 is heated to a liquid crystal state. As a result, as shown in FIG. 4 (c), the side chain type polymer film 7 has different amounts of light Fryce rearrangement reaction between the direction parallel to and perpendicular to the direction of polarized light irradiated with ultraviolet rays. Because the light Fryce rearrangement body 8 (a) has stronger anchoring force than the side chain 8 before rearrangement, when a certain amount of light Frye rearrangement body is generated, it is parallel to the polarization direction of the ultraviolet light The orientation is self-organized to reorient the side chain 8 containing the liquid crystal component. As a result, the small anisotropy of the coating film 7 caused by the Fries rearrangement reaction by light increases due to heat, and a greater anisotropy is imparted to the coating film 7.

Therefore, the coating film used in the method of the present invention can be a liquid crystal alignment film with excellent alignment control performance by sequentially radiating the coating film with polarized ultraviolet rays and heat treatment to efficiently introduce anisotropy.

In addition, the coating film used in the method of the present invention optimizes the amount of polarized ultraviolet radiation to the coating film and the heating temperature of the heat treatment. This makes it possible to efficiently introduce anisotropy into the coating film.

The optimum amount of polarized ultraviolet radiation for introducing a highly effective anisotropy into the coating film used in the present invention corresponds to the photocrosslinking reaction or photoisomerization reaction, or photo-Fryes in the photosensitive film of the coating film. The amount of rearrangement reaction is the optimal amount of polarized ultraviolet radiation. As a result of irradiating the coating film used in the present invention with polarized ultraviolet light, the photocrosslinking reaction, photoisomerization reaction, or photo-Fries rearrangement reaction has a small number of photosensitive groups on the side chain, and the sufficient photoreaction amount cannot be obtained . At this time, sufficient self-organization cannot be performed even after heating. In addition, the coating film used in the present invention has a structure having a photo-crosslinkable group. As a result of the irradiation of polarized ultraviolet light, the cross-linking reaction When there are too many photosensitive groups in the side chain, the cross-linking reaction between the side chains proceeds excessively. At this time, the obtained coating film becomes rigid, which may prevent subsequent self-organization by heating. In addition, as for the coating film used in the present invention, and the structure having a light Fryce rearrangement base is irradiated with polarized ultraviolet light, when the photosensitive group of the side chain of the light Fryce rearrangement reaction becomes excessive, the Liquid crystallinity is excessively reduced. At this time, the liquid crystallinity of the obtained film is also lowered, which may prevent subsequent self-organization by heating. In addition, when a structure with a light Fryce rearrangement is irradiated with polarized ultraviolet light, when the amount of ultraviolet radiation is too large, the side chain polymer will photoly decompose, which may prevent subsequent self-organization by heating. Happening.

Therefore, in the coating film used in the present invention, the optimum amount of the photo-crosslinking reaction or the photo-isomerization reaction or the photo-Frys rearrangement reaction of the photosensitive group of the side chain by irradiation of polarized ultraviolet rays is such that The photosensitive group of the side chain polymer film is preferably 0.1 mol% to 40 mol%, and more preferably 0.1 mol% to 20 mol%. When the amount of the photosensitive group of the side chain that undergoes the photoreaction is in this range, the self-organization of the subsequent heat treatment can be effectively performed, and anisotropy in the film can be formed with high efficiency.

The coating film used in the method of the present invention optimizes the photocrosslinking reaction or photoisomerization reaction of the photosensitive group in the side chain of the side chain type polymer film by optimizing the irradiation amount of polarized ultraviolet light. The amount of Fries rearrangement reaction is optimized. Therefore, together with the subsequent heat treatment, it is possible to efficiently introduce anisotropy into the coating film used in the present invention. At this time, the preferable amount of polarized ultraviolet rays can be evaluated based on the ultraviolet absorption of the coating film used in the present invention.

That is, for the coating film used in the present invention, After ultraviolet light irradiation, ultraviolet absorption in a direction parallel to the polarization direction of polarized ultraviolet light and ultraviolet absorption in a vertical direction. From the measurement results of ultraviolet absorption, the difference between the ultraviolet absorbance in the direction parallel to the polarization direction of the polarized ultraviolet rays and the ultraviolet absorbance in the vertical direction in the coating film was evaluated as ΔA. In addition, the maximum value (ΔAmax) of ΔA achieved in the coating film used in the present invention and the amount of polarized ultraviolet radiation to achieve it were obtained. In the manufacturing method of the present invention, based on the amount of polarized ultraviolet radiation to achieve this ΔAmax, a preferable amount of polarized ultraviolet radiation can be determined in the manufacture of the liquid crystal alignment film.

In the manufacturing method of the present invention, it is preferable that the irradiation amount of polarized ultraviolet rays to the coating film used in the present invention is set within a range of 1% to 70% of the amount of polarized ultraviolet rays to achieve ΔAmax, and more preferably set to 1% to 50. Within the range of%. In the coating film used in the present invention, the irradiation amount of polarized ultraviolet rays in the range of 1% to 50% of the amount of polarized ultraviolet rays to achieve ΔAmax is equivalent to 0.1 moles of the entire photosensitive group of the side chain polymer film. The amount of polarized ultraviolet light at which the light cross-linking reaction is carried out in the ear% to 20 mole%.

From the above, according to the manufacturing method of the present invention, in order to introduce anisotropy into the coating film with high efficiency, the liquid crystal temperature range of the side chain polymer is used as a reference, and the preferred heating temperature may be determined as described above. Therefore, for example, when the liquid crystal temperature range of the side chain polymer used in the present invention is 100 ° C to 200 ° C, the heating temperature after the polarized ultraviolet radiation is preferably set to 90 ° C to 190 ° C. Thereby, a greater anisotropy is imparted to the coating film used in the present invention.

As such, the liquid crystal display element provided by the present invention displays light External stress such as heat or heat shows high reliability.

As described above, a substrate for a lateral electric field drive type liquid crystal display element manufactured by the method of the present invention or a lateral electric field drive type liquid crystal display element having the substrate is excellent in reliability, and can be applied to large-screen and high-definition liquid crystal televisions. .

[Example]

The examples use abbreviations as follows.

(Methacrylic monomer)

MA1 is synthesized by a synthesis method described in a patent document (WO2011-084546).

MA2 is synthesized by a synthesis method described in a patent document (Japanese Patent Laid-Open No. 9-118717).

(Organic solvents)

THF: tetrahydrofuran

NMP: N-methyl-2-pyrrolidone

BC: butyl cellolysin

(Polymerization initiator)

AIBN: 2,2’-azobisisobutyronitrile

[Measurement of phase transition temperature]

The liquid crystal phase transition temperature of the polymer obtained in the examples was measured using differential scanning calorimetry (DSC) DSC3100SR (manufactured by Mac Science).

<Synthesis example 1>

MA1 (15.29 g, 46 mmol) and MA2 (56.37 g, 184 mmol) were dissolved in THF (655.1 g), and after degassing with a diaphragm pump, AIBN (1.13 g, 6.9 mmol) was added and degassed again. Then, it reacted at 60 degreeC for 20 hours, and obtained the polymer solution of a methacrylate. This polymer solution was dropped into diethyl ether (7000 ml), and the resulting precipitate was filtered. This precipitate was washed with diethyl ether and dried under reduced pressure in an oven at 40 ° C to obtain a methacrylate polymer powder. This polymer had a number average molecular weight of 15,000 and a weight average molecular weight of 40,500.

The liquid crystal phase transition temperature of the obtained methacrylate polymer was 120 ° C to 185 ° C.

NMP (54.0 g) was added to the obtained methacrylate polymer powder (6.0 g), and the mixture was stirred at room temperature for 5 hours to be dissolved. BC (40.0 g) was added to this solution, and a liquid crystal alignment agent (A) was obtained by stirring.

<Example 1> (The production of liquid crystal cells)

Using the liquid crystal alignment agent (A) obtained in Synthesis Example 1, a liquid crystal cell was prepared in the following procedure.

The substrate is a glass substrate having a size of 30 mm × 40 mm and a thickness of 0.7 mm, and is provided with comb-shaped pixel electrodes formed by patterning an ITO film. The pixel electrode has a comb-tooth shape formed by bending a central portion and arranging a plurality of electrode elements in a zigzag shape. The width in the short-side direction of each electrode element is 10 μm, and the interval between the electrode elements is 20 μm. The pixel electrode forming each pixel is composed of electrode elements with a curved central portion and a plurality of ㄑ -shaped electrode elements arranged. Therefore, the shape of each pixel is not a rectangular shape, but is provided with a similar ㄑ character similar to the electrode element, which is bold and curved at the center shape. In addition, each pixel has a first region on the upper side and a second region on the lower side of the curved portion divided up and down with the central curved portion as a boundary. When comparing the first region and the second region of each pixel, the formation direction of the electrode elements constituting their pixel electrodes is different. That is, when the alignment processing direction of the liquid crystal alignment film described later is used as a reference, the electrode element of the pixel electrode forms an angle of + 15 ° (clockwise) in the first region of the pixel, and the pixel electrode in the second region of the pixel The electrode elements form an angle of -15 ° (clockwise). That is, the directions of the first region and the second region of each pixel in the substrate surface rotation (in-plane switching) caused by the voltage applied between the pixel electrode and the counter electrode are mutually The opposite direction.

The liquid crystal alignment agent (A) obtained in Synthesis Example 1 was spin-coated on the prepared substrate with electrodes. Next, it was dried on a hot plate at 70 ° C. for 90 seconds to form a liquid crystal alignment film with a film thickness of 100 nm. Next, the coated film surface was irradiated with ultraviolet light of 313 nm at 10 mJ / cm ² through a polarizing plate, and then heated on a heating plate at 150 ° C. for 10 minutes (single firing), and then cooled (cooled) to the substrate at room temperature, A 150 ° C. heating plate was heated for 10 minutes (two firings) to obtain a substrate with a liquid crystal alignment film. Similarly, when the irradiation amount of ultraviolet rays is 10 mJ / cm ² to 100 mJ / cm ² , different substrates are produced at intervals of 10 mJ / cm ² , and at 100 mJ / cm ² or more, at intervals of 50 mJ / cm ² .

In addition, a coating film was also formed on a glass substrate having a columnar spacer having a height of 4 μm as an opposing substrate without forming an electrode, and subjected to an alignment treatment. A sealant (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) was printed on a liquid crystal alignment film of one substrate. Next, another substrate is bonded so that the alignment direction of the liquid crystal alignment film surface becomes 0 °, and then the sealant is thermally cured to produce an empty cell. A liquid crystal MLC-2041 (manufactured by Merck Co., Ltd.) was injected into the empty cell by a reduced-pressure injection method, and the injection port was sealed to obtain a liquid crystal cell having a structure of a liquid crystal display element having an IPS (lateral switching) mode.

(Alignment observation)

A liquid crystal cell was produced in the above-mentioned manner. Then, re-alignment treatment was performed in an oven at 120 ° C for 60 minutes. Then, the polarizing plates were placed in an orthogonal state and observed with a polarizing microscope. When the LCD cell is rotated, there is no light when the display state is black. In the case of a point or poor alignment, it was evaluated as good. The irradiation amount of the ultraviolet rays is as described above. As a result of observing the alignment properties for the different substrates, the margin of the irradiation amount with good alignment is shown in Table 1.

<Example 2>

A liquid crystal cell was produced in the same manner as in Example 1 except that the temperature of the two firing treatments was set to 130 ° C. Using the prepared liquid crystal cell, the alignment was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

<Comparative Examples 1 to 2>

A liquid crystal cell was produced in the same manner as in Example 1 except that the cooling step was performed and the secondary firing treatment was not included. Using the prepared liquid crystal cell, the alignment was evaluated in the same manner as in Example 1.

The evaluation results are shown in Table 1.

The results are shown in Table 1.

It can be seen from the results that the sintered bar was subjected to two firing steps after the spin-cooling step. The part is to expand the margin of the UV irradiation amount showing good liquid crystal alignment.

This is to determine the orientation orientation of the main polymer skeleton by a single firing, but it is estimated that the oligomerization above or near the transparent point at the temperature of the first firing is then cooled to below the glass transition temperature. The material component or the low molecular weight component is in a glass state in a disordered alignment state (Comparative Examples 1, 2). Here, it is estimated that when heating is performed again at a temperature above the glass transition temperature and below the liquid crystal transparent point, only the oligomer component or the low molecular weight component follows the orientation orientation of the main polymer skeleton determined by a single firing. Realignment improves the alignment of the entire alignment film. (These are theoretical guesses and do not limit the invention)

Claims (17)

A method for manufacturing a substrate with a liquid crystal alignment film, which is to obtain a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element that is provided with alignment control energy by having the following steps: [I] will contain (A) in a specific temperature range A step of forming a coating film by coating a polymer composition having a photosensitive side chain polymer and (B) an organic solvent with liquid crystallinity on a substrate having a conductive film for driving a lateral electric field; [II] to [I ] The step of irradiating polarized ultraviolet rays of the obtained coating film; [III] a step of heating the coating film obtained by [II]; and [IV] cooling the coating film heated by [III] to a level not exceeding the surface of the coating film A step of heating the glass transition temperature to a temperature equal to or higher than the glass transition temperature. For example, the method of claim 1 in the patent scope, wherein the cooling temperature of the coating film in the step [IV] is a temperature lower than the glass transition point temperature (Tg) of the side chain polymer of the component (A) by more than 10 ° C. For example, the method of claim 1 or 2, in which the heating temperature of the coating film after ultraviolet irradiation and the reheating temperature after cooling are above the glass transition temperature of the coating film surface and do not reach the isotropy of the coating film surface. Phase transition (Isotropic Phase Transition) temperature. For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain that causes photocrosslinking, photoisomerization, or optical Fries rearrangement. For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (1) to (6): (Wherein A, B, and D each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O -Or-O-CO-CH = CH-; S is an alkylene group having 1 to 12 carbon atoms, and the hydrogen atoms to which they are bonded may be substituted with a halogen group; T is a single bond or 1 to carbon number 12 alkyl groups, and the hydrogen atoms to which they are bonded may be substituted with halogen groups; Y ₁ represents a monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, and carbon number 5 ~ 8 alicyclic hydrocarbon rings, or the same or different 2 ~ 6 rings selected from their substituents are bonded through a bonding group B, and the hydrogen atoms to which they are bonded can be independent of each other Via -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, C1-C5 alkyl group or C1-C5 alkyloxy group is substituted; Y ₂ is selected from bivalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, carbon number 5 ~ The alicyclic hydrocarbons of 8 and the groups of these groups, and the hydrogen atoms to which they are bonded can also independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, 1 to 5 carbons, or 1 to 5 carbons Alkyloxy substituted; R & lt represents a hydroxyl group, an alkoxy group having a carbon number of 1 to 6, or represents the same as defined in the Y _1; X represents a single bond, -COO -, - OCO -, - N = N -, - CH = CH-, -C≡C-, -CH = CH-CO-O-, or -O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; Cou means Coumarin 6-yl group or coumarin-7-yl group, and the hydrogen atoms to which they are bonded may each independently pass -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN , Halo, alkyl having 1 to 5 carbons, or alkyloxy having 1 to 5 carbons; one of q1 and q2 is 1 and the other is 0; q3 is 0 or 1; P and Q Each is independently a group selected from the group consisting of a divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, an alicyclic hydrocarbon having 5 to 8 carbon atoms, and a combination thereof, but X is When -CH = CH-CO-O-, -O-CO-CH = CH-, P or Q on the side to which -CH = CH- is bonded is an aromatic ring, and when the number of P is 2 or more, P may be mutually The same or different, when the number of Q is 2 or more, Q may be the same or different; l1 is 0 or 1; l2 is an integer of 0 ~ 2; when l1 and l2 are 0, when T is a single bond, A Also represents a single bond; when l1 is 1, when T is a single bond, B also represents a single bond; H and I are each independently A group selected from a divalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and a combination thereof). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (7) to (10): (In the formula, A, B, and D each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O -, Or -O-CO-CH = CH-; Y ₁ represents a ring selected from monovalent benzene rings, naphthalene rings, biphenyl rings, furan rings, pyrrole rings, and alicyclic hydrocarbons having 5 to 8 carbon atoms, Or two or six rings selected from their substituents, which are the same or different, are bonded through a bonding group B, and the hydrogen atoms to which they are bonded can also each independently pass -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, a halogen group, an alkyl group having 1 to 5 carbon atoms, Or alkyloxy with 1 to 5 carbon atoms; X represents a single bond, -COO-, -OCO-, -N = N-, -CH = CH-, -C≡C-, -CH = CH-CO -O-, or -O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; l represents an integer from 1 to 12; m represents an integer from 0 to 2, m1 and m2 represent An integer of 1 to 3; n represents an integer of 0 to 12 (but when n = 0, B is a single bond); Y ₂ is selected from a bivalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, The alicyclic hydrocarbons with 5 to 8 carbons and the bases of their groups, and the hydrogen atoms to which they are bonded can also be independent of each other _{-NO 2, -CN, -CH = C} (CN) 2, -CH = CH-CN, halo, or alkyl having 1 to 5 carbon atoms of the alkyl group having 1 to 5 substituents; R & lt represents a hydroxyl group , An alkoxy group having 1 to 6 carbon atoms, or the same definition as Y ₁ ). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain selected from the group consisting of the following formulae (11) to (13): (In the formula, each A independently represents a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O-, or- O-CO-CH = CH-; X represents a single bond, -COO-, -OCO-, -N = N-, -CH = CH-, -C≡C-, -CH = CH-CO-O-, Or -O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; l represents an integer from 1 to 12, m represents an integer from 0 to 2, and m1 represents an integer from 1 to 3; R represents a ring selected from a monovalent benzene ring, a naphthalene ring, a biphenyl ring, a furan ring, a pyrrole ring, and an alicyclic hydrocarbon ring having 5 to 8 carbon atoms, or 2 to 2 of the same or different selected from their substituent A base formed by bonding 6 rings via a bonding group B, and the hydrogen atoms to which they are bonded may each independently pass -COOR ₀ (where R ₀ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms) , -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, alkyl having 1 to 5 carbon atoms, or alkyloxy having 1 to 5 carbon atoms, or Represents a hydroxyl group or an alkoxy group having 1 to 6 carbon atoms). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain represented by the following formula (14) or (15): (In the formula, each A independently represents a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O-, or- O-CO-CH = CH-; Y ₁ represents a ring selected from monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, and alicyclic hydrocarbon having 5 to 8 carbon atoms, or from among them The same or different 2 to 6 rings selected by the substituents are the bases bonded through the bonding group B, and the hydrogen atoms to which they are bonded can also each independently pass -COOR ₀ (where R ₀ represents hydrogen Atomic or carbon number 1 to 5 alkyl group), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo group, alkyl group of 1 to 5 carbon number, or carbon number 1 to 5 alkyloxy substitution; l represents an integer of 1 to 12, m1, m2 represents an integer of 1 to 3). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain represented by the following formula (16) or (17): (In the formula, A represents a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O-, or -O- CO-CH = CH-; X represents a single bond, -COO-, -OCO-, -N = N-, -CH = CH-, -C≡C-, -CH = CH-CO-O-, or- O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; l represents an integer from 1 to 12, and m represents an integer from 0 to 2). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain selected from the group consisting of the following formula (18) or (19): (In the formula, A and B each independently represent a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O-, Or -O-CO-CH = CH-; Y ₁ represents a ring selected from monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring, and alicyclic hydrocarbon ring having 5 to 8 carbon atoms, or from The same or different 2 to 6 rings selected by their substituents are bonded to each other via a bonding group B, and the hydrogen atoms to which they are bonded can also independently pass -COOR ₀ (where R ₀ Represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, a halogen group, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having a carbon number of 1 to 5 substituents; and one of those q2 q1 is 1 and the other is 0; l represents an integer of 1 to 12, m1, m2 represents an integer of 1 to 3; ₁ represents a hydrogen atom R & lt , -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, alkyl having 1 to 5 carbons, or alkyloxy having 1 to 5 carbons). For example, the method of claim 1 or 2, wherein the component (A) has a photosensitive side chain represented by the following formula (20): (In the formula, A represents a single bond, -O-, -CH _2- , -COO-, -OCO-, -CONH-, -NH-CO-, -CH = CH-CO-O-, or -O- CO-CH = CH-; Y ₁ represents a ring selected from monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, pyrrole ring and alicyclic hydrocarbon having 5 to 8 carbon atoms, or from these substituents The same or different selected 2 to 6 rings are bonded through a bonding group B, and the hydrogen atoms to which they are bonded may also independently pass through -COOR ₀ (where R ₀ represents a hydrogen atom or a carbon Alkyl groups of 1 to 5), -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, alkyl groups of 1 to 5 carbons, or 1 to 5 carbons Alkyloxy substitution; X represents a single bond, -COO-, -OCO-, -N = N-, -CH = CH-, -C≡C-, -CH = CH-CO-O-, or- O-CO-CH = CH-, when the number of X is 2, X may be the same as or different from each other; l represents an integer from 1 to 12, and m represents an integer from 0 to 2). For example, the method of claim 1 or 2, wherein the component (A) has any liquid crystal side chain selected from the group consisting of the following formulae (21) to (31): (Wherein A and B have the same definitions as above; Y ₃ is selected from monovalent benzene ring, naphthalene ring, biphenyl ring, furan ring, nitrogen-containing heterocyclic ring, and alicyclic hydrocarbon having 5 to 8 carbon atoms. And the groups of these groups, and the hydrogen atoms to which they are bonded may each independently pass -NO ₂ , -CN, a halogen group, an alkyl group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms. 5 alkyloxy substitution; R ₃ represents a hydrogen atom, -NO ₂ , -CN, -CH = C (CN) ₂ , -CH = CH-CN, halo, monovalent benzene ring, naphthalene ring, Benzene ring, furan ring, nitrogen-containing heterocyclic ring, alicyclic hydrocarbon having 5 to 8 carbons, alkyl having 1 to 12 carbons, or alkoxy having 1 to 12 carbons; one of q1 and q2 is 1 And the other is 0; l is an integer from 1 to 12, and m is an integer from 0 to 2. However, in formulas (23) to (24), the total of all m is 2 or more, and formulas (25) to (26) Among them, the total of all m is 1 or more, m1, m2 and m3 each independently represent an integer of 1 to 3; R ₂ represents a hydrogen atom, -NO ₂ , -CN, a halogen group, a monovalent benzene ring, a naphthalene ring, a Benzene ring, furan ring, nitrogen-containing heterocyclic ring, and alicyclic hydrocarbon and alkyl group or alkyloxy group having 5 to 8 carbon atoms; Z ₁ and Z ₂ represent single bonds, -CO-, -CH ₂ O-, -CH = N-, -CF _2- ). A substrate having a liquid crystal alignment film for a lateral electric field drive type liquid crystal display element, which is characterized by being manufactured by a method according to any one of claims 1 to 12 of the scope of patent application. A lateral electric field drive type liquid crystal display element is characterized in that it has a substrate with the scope of application for item 13 of the patent. A method for manufacturing a liquid crystal display element, which is characterized by obtaining a lateral electric field drive type liquid crystal display element with the following steps: a step of preparing a substrate (the first substrate) for which the scope of the patent application is item 13; and obtaining a liquid crystal alignment film having the following The step of the second substrate is to obtain a liquid crystal alignment film that imparts alignment control ability by having the following steps [I '] to [III']: [I '] coating the second substrate with the following component (A) And (B) the polymer composition to form a coating film: (A) a photosensitive side chain polymer that exhibits liquid crystallinity in a specific temperature range, and (B) an organic solvent; [II '] to [I '] The step of irradiating the obtained coating film with polarized ultraviolet light; [III'] The step of heating the coating film obtained by [II ']; and [V] The step of obtaining a liquid crystal display element, which is performed by liquid crystal The liquid crystal alignment films of the first and second substrates face each other, and the first and second substrates are arranged to face each other. For example, the method of claim 15 in the patent application method, wherein the step of obtaining the second substrate is further including [IV '] cooling the coating film heated with [III'] to a temperature below the glass transition temperature of the coating film surface. And a step of heating to a temperature above the glass transition temperature. A lateral electric field drive type liquid crystal display element, which is characterized by being manufactured by a method applying for item 15 or 16 of the scope of patent application.