JPH1195227A - Oriented film in common use as protective film for liquid crystal, liquid crystal holding substrate using the same and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To embody the adhesion property to glass substrates and color filters, etc., and excellent orientability and planarization characteristic by forming a liquid film consisting of a resin compsn. contg. specific polyamide acid on an electrode surface and drying the film by heating, thereby forming a polyamide film. SOLUTION: The liquid film consisting of the resin compsn. contg. the polyamide acid of 1000 to 20000 in weight average mol.wt. is formed by a printing method on the surface of the liquid crystal holding substrate formed with the electrode and is dried by heating, by which the polyamide film is formed. The resin compsn. contg. the polyamide acid contains a solvent in such a manner that a solid content concn. of 7 to 60 wt.% is attained. The viscosity of the soln. thereof is preferably 30 to 1000 mpa.s. The polyamide acid is preferably obtd. by bringing a diamine component contg. at least one kind of the compds. selected from a group consisting of a rigid diamine compd. having a benzene ring, rigid dihydrazine compd. having a benzene ring and diamine compd. having a sulfone group and/or sulfide group and a tetracarboxylic dianhydride component into reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a protective film / alignment film for liquid crystal, a liquid crystal sandwiching substrate, and a liquid crystal display device.

[0002]

2. Description of the Related Art In a current color thin film transistor-type liquid crystal display device, a color filter is indispensable and is formed by a dyeing method, a printing method, an electrodeposition method, a pigment dispersion method or the like. In order to prevent the components contained in the liquid crystal from being eluted into the liquid crystal, a protective film is provided, and an inorganic thin film (transparent electrode) made of ITO (indium tin oxide) or the like is deposited thereon. Is provided with a liquid crystal alignment film which is a thin film having a liquid crystal alignment function. Properties required for the color filter protective film include heat resistance, chemical resistance, adhesion to a glass substrate and a color filter, transparency, and the like. JP-A-58-196506 and JP-A-62-119 disclose resin film materials having excellent properties such as heat resistance and chemical resistance.
No. 501, etc .;
A polyglycidyl methacrylate resin described in Japanese Patent No. 216307 and a melamine resin disliked in Japanese Patent Application Laid-Open No. 63-131103 have been proposed. Further epoxy resin,
Polyimide resins have also been proposed.

On the other hand, 0.2 μm
Although there is an uneven structure of about 1 μm, a protective film having a flattening function is not particularly used, and a polyimide-based liquid crystal alignment film of about 70 nm is used. By this step,
The reduction of the contrast ratio due to the domain generation around the thin film transistor and the uneven brightness due to the gap failure have occurred, and these solutions have been an urgent issue. In particular, JP-A-6
In the liquid crystal display device described in JP-A-160878, a comb-shaped electrode is used in addition to a thin film transistor. Therefore, the uneven structure of the substrate is severe, and in order to reduce luminance unevenness due to a gap defect, the substrate is flattened. It is necessary to make the gap uniform. In order to form a protective film having a thickness of 0.3 to 3 μm so as to have a flattening function, a spin coating method is generally used. In this method, the protective film portion in contact with the sealant is formed by photolithography. It has to be removed, and there is a problem that it cannot be easily patterned.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and has good properties such as heat resistance, chemical resistance, adhesion to a glass substrate or a color filter, transparency and printability. It is another object of the present invention to provide a protective film / alignment film for liquid crystal which is excellent in alignment and flatness, a liquid crystal sandwiching substrate having the protective film / alignment film, and a liquid crystal display device using the same.

[0005]

According to the present invention, a liquid film made of a resin composition containing a polyamic acid having a weight average molecular weight of 1,000 to 20,000 is formed on a surface of a liquid crystal sandwiching substrate on which electrodes are formed by a printing method. And a polyimide film formed by heating and drying. The present invention also relates to the protective film and alignment film for liquid crystal, wherein the resin composition containing a polyamic acid contains a solvent such that the solid content concentration is 7 to 60% by weight, and the viscosity is 30 to 1000 mPa · s. . Further, the present invention, in these liquid crystal protective film and alignment film, polyamic acid,
(A) a rigid diamine compound having a benzene ring,
A diamine component and a tetracarboxylic dianhydride component containing at least one compound selected from the group consisting of (b) a rigid dihydrazide compound having a benzene ring and (c) a diamine compound having a sulfone group and / or a sulfide group. And a protective film and an alignment film for liquid crystal obtained by reacting

The present invention also provides a liquid crystal protective film / alignment film which comprises (a) a rigid diamine compound having a benzene ring, (b) a rigid dihydrazide compound having a benzene ring, and (c) a sulfone group. And / or the total amount of compounds selected from the group consisting of diamine compounds having a sulfide group is 30 mol% of the total number of moles of the diamine component.
The present invention relates to the above-described protective film and alignment film for liquid crystal. In the present invention, the tetracarboxylic dianhydride component may be an aliphatic tetracarboxylic dianhydride and / or an alicyclic tetracarboxylic dianhydride in an amount of at least 30 mol% of the total number of moles of the acid dianhydride component. The present invention also relates to a protective film and an alignment film for liquid crystal.

In the present invention, the tetracarboxylic dianhydride is represented by the general formula (I):

Embedded image [Wherein n represents an integer of 2 to 20], wherein the tetracarboxylic dianhydride is represented by 2
The present invention relates to the protective film and alignment film for liquid crystal containing 0 mol% or more.
In addition, the present invention relates to the protective film and alignment film for liquid crystal, wherein the solvent contains a lactone-based solvent in an amount of 30% by weight or more based on the total weight of the solvent.

Further, the present invention relates to a liquid crystal sandwiching substrate having any one of the above-mentioned protective film and alignment film for liquid crystal. The present invention also provides an electrode on the side of the liquid crystal sandwiching substrate facing the liquid crystal,
The present invention relates to a liquid crystal display device having any one of the above-mentioned protective film and alignment film for liquid crystal on the substrate and the electrodes.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The resin composition used for producing the protective film and alignment film for a liquid crystal of the present invention contains a polyamic acid as a main component as described above. As the polyamic acid used in the present invention, various compounds can be used. (A) A rigid diamine compound having a benzene ring, (b) a rigid dihydrazide compound having a benzene ring, and (c) a sulfone It is preferably obtained by reacting a diamine component containing at least one compound selected from the group consisting of diamine compounds having a group and / or a sulfide group with a tetracarboxylic dianhydride component.

Of the diamine components, (a) the rigid diamine compound having a benzene ring is preferably a diamine compound having one benzene ring in the molecule, for example, a compound represented by the general formula (II):

Embedded image [Wherein, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms]. Specific examples include p-phenylenediamine, m-phenylenediamine, o-phenylenediamine and the like.

The (b) rigid dihydrazide compound having a benzene ring is preferably a dihydrazide compound having one benzene ring in the molecule, for example, a compound of the general formula (III)

Embedded image [Wherein R ¹ , R ² , R ³ and R ⁴ represent the same as above]
The dihydrazide compound shown by these is mentioned. Specific examples include isophthalodil dihydrazide, terephthalodil dihydrazide, and the like.

Further, (c) the diamine compound having a sulfone group and / or a sulfide group includes a compound represented by the general formula (I)
V), (V) and (VI)

Embedded image [Wherein, R ¹ , R ² , R ³ and R ⁴ represent those described above;
X is -S- or -SO ₂ -, Y represents the -O -, - CO
-, - S -, - SO 2 -, - CONH -, - (CH 2)
_{m -, - C (CF 3} ) 2 - or -C (CH _{3) 2} - represents, m can be mentioned diamine compound represented by representing] a number of 1-8.

Specific examples of these diamine compounds include 4,4'-diaminodiphenyl sulfone,
4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfide, 3,4'-diaminodiphenylsulfide, 3,3'-diaminodiphenylsulfide, bis [4- (3- Aminophenoxy) phenyl] sulfone,
Bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfide and the like can be mentioned.

The above-mentioned diamine compounds (a) to (c) can be used alone or in combination of two or more. In order to ensure good liquid crystal alignment function and light transmittance, it is preferable to adjust the total amount of these diamine compounds to be 30 mol% or more of the total number of moles of the diamine component.

As the diamine component, the above (a) to
Other copolymerizable diamine compounds can be used instead of the diamine compound (c) or together with the diamine compounds (a) to (c). Other copolymerizable diamine components include 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, and 4,4 '.
-Diaminodiphenylmethane, 2,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane,
3,3'-diaminodiphenylmethane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane,
2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (3
-Aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenoxy) hexafluoropropane, 1,6-hexamethylenediamine, 1,
8-octamethylenediamine, 1,10-decamethylenediamine, 1,12-dodecamethylenediamine, azelaic dihydrazide, sebacic dihydrazide, 2,6
-Naphthoic dihydrazide, 2,4'-diamino-3-
Methyl-stearyl phenyl ether, 2,4'-diamino-3-methyl-lauryl phenyl ether, 2,
4'-diamino-3-methyl-palmitylphenyl ether, 2,4'-diamino-1-octyloxybenzene, 2,2-bis [4- (4-aminophenoxy) phenyl] octane, 2,2-bis [4- (4-aminophenoxy) phenyl] tridecane, 2,2-bis [4-
(4-aminophenoxy) phenyl] pentadecane, bis [4- (4-aminobenzoyloxy) benzoic acid] decane, bis [4- (4-aminobenzoyloxy) benzoic acid] dodecane, bis [4- (4-amino Benzoyloxy) benzoic acid] methylcyclohensan, bis [4-
(4-aminobenzoyloxy) benzoic acid] methine, bis [4- (4-aminobenzoyloxy) benzoic acid] butane, diaminosiloxane, 1,3-di (3-aminopropyl) -1,1,3,3 -Tetramethyldisiloxane and the like, and one or more of these can be used.

On the other hand, the tetracarboxylic dianhydride component is not particularly limited, and various ones can be used, but aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and general formula (I)

Embedded image [Where n represents an integer of 2 to 20], such as tetracarboxylic dianhydride, and other copolymerizable tetracarboxylic dianhydrides.

The aliphatic tetracarboxylic dianhydride and the alicyclic tetracarboxylic dianhydride include 1,2,3,4
-Butanetetracarboxylic dianhydride, 1,2,3,4-
Cyclobutanetetracarboxylic dianhydride, 1,2,3
4-cyclopentanetetracarboxylic dianhydride, 1,
2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-biscyclohexanetetracarboxylic dianhydride, bicyclo (2,2,2) oct-7
-Ene-2,3,5,6-tetracarboxylic dianhydride,
Octyl succinic dianhydride, dodecyl succinic dianhydride, bis (bicyclo [2,2,1] heptane-2,3-
Dicarboxylic anhydride) and the like, and these can be used alone or in combination of two or more. In order to ensure flatness and good light transmittance, an aliphatic tetracarboxylic dianhydride and / or an alicyclic tetracarboxylic dianhydride are used in an amount of 30 mol% based on the total number of moles of the acid dianhydride component. It is preferable to use the above.

The use of the tetracarboxylic dianhydride represented by the general formula (I) in an amount of 20 mol% or more of the total number of moles of the acid dianhydride component provides good flatness and light transmission. Sex can be obtained. Examples of the tetracarboxylic dianhydride represented by the general formula (I) include dimethylene trimellitate dianhydride, trimethylene trimellitate dianhydride, tetramethylene trimellitate dianhydride, Pentamethylene trimellitate dianhydride, hexamethylene trimellitate dianhydride, heptamethylene trimellitate dianhydride, octamethylene trimellitate dianhydride, decamethylene trimellitate dianhydride, Dodecamethylene trimellitate dianhydride, hexadecamethylene trimellitate dianhydride, octadecamethylene trimellitate dianhydride, icosamethylene trimellitate dianhydride, etc. Or a combination of two or more.

Other copolymerizable tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3 ',
4,4'-biphenyltetracarboxylic dianhydride, benzophenonetetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3 ', 4,4'-diphenylmethanetetracarboxylic dianhydride, 3,3', 4,4'-diphenylsulfonetetracarboxylic dianhydride, 3,3 ',
4,4'-tetracarboxyphenyl ether dianhydride, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropanoic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride And 1,3-bis (3,4-dicarboxyphenyl) tetradimethylsiloxane carboxylic dianhydride. These can be used alone or in combination of two or more.
Examples of the tetracarboxylic dianhydride include the above-mentioned aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, tetracarboxylic dianhydride represented by the general formula (I), and others. Among these copolymerizable tetracarboxylic dianhydrides, one or more kinds can be used.

In order to produce the polyamic acid used in the present invention, the ratio of the total number of moles of the diamine component to the total number of moles of the acid dianhydride component is 0.8 to 1.2. The reaction is carried out within a range, preferably 1.0. The diamine component and the acid dianhydride component are dissolved in an inert solvent and reacted to obtain a polyamic acid. As the inert solvent,
It is not necessary to dissolve all of the above monomers, but it is preferable to dissolve the resulting polyamic acid.
Methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, γ-butyrolactone, ε-caprolactone, γ-caprolactone, γ-valerolactone, dimethylsulfoxide, 1,4-dioxane, and the like. One or more of these can be used. In order to improve the film forming property during curing, a lactone-based solvent having a high vapor pressure is used in an amount of 30% of the total weight of the solvent.
Preferably, it is used in an amount of at least% by weight. Lactone solvents include γ-butyrolactone, ε-caprolactone, γ-
Caprolactone, γ-valerolactone and the like.

In addition to the above solvent, another solvent can be added before or after the reaction in order to improve the wettability to the liquid crystal sandwiching substrate. Other solvents, for example,
Examples include ethyl cellosolve, ethyl cellosolve acetate, butyl cellosolve, butyl cellosolve acetate, xylene, toluene, 1-ethoxy-2-acetoxypropane, diisobutyl ketone, and methyl-n-hexyl ketone.

The reaction between the diamine component and the acid dianhydride component is preferably performed at a temperature of -30 ° C to 100 ° C for 30 minutes to 48 hours. After completion of the reaction, the reaction temperature is adjusted to 60 ° C to 250 ° C, preferably 80 ° C to 20
The heat treatment is preferably performed at 0 ° C. for a reaction time of 30 minutes to 72 hours. In the present invention, the weight average molecular weight of the polyamic acid is 100
The molecular weight is adjusted so as to be 0 to 20,000. In the present invention, the weight average molecular weight is a weight average molecular weight in terms of standard polystyrene measured by gel permeation chromatography using a standard polystyrene calibration curve.

Further, in order to obtain good flatness, the solid content is 7 to 60% by weight and the viscosity is 30 to 1000 mPa · s, preferably the solid content is 10 to 50% by weight and the viscosity is 30 to 2%.
The viscosity is adjusted to 50 mPa · s, more preferably to a solid content of 15 to 35% by weight, and a viscosity of 30 to 60 mPa · s.
By this adjustment, a resin composition exhibiting good printability as well as good flatness during film formation can be obtained.

The protective film / alignment film for liquid crystal of the present invention is formed by printing the above resin composition on the surface of the liquid crystal sandwiching substrate on which the electrode is formed, heating and drying to dehydrate and close the polyimide. It is obtained by forming a film. In order to improve the adhesion between the polyimide resin and the glass,
Coupling agents such as silane coupling agents and titanium coupling agents can be added to the resin composition containing polyamic acid.

As the silane coupling agent, for example,
γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, γ-aminopropyltributoxysilane, γ-aminoethyltriethoxysilane, γ-aminoethyltrimethoxysilane, γ- Aminoethyltripropoxysilane, γ-aminoethyltributoxysilane,
Examples include γ-aminobutyltriethoxysilane, γ-aminobutyltrimethoxysilane, γ-aminobutyltripropoxysilane, and γ-aminobutyltributoxysilane. Examples of the titanium coupling agent include γ-aminopropyltriethoxytitanium, γ-aminopropyltrimethoxytitanium, γ-aminopropyltripropoxytitanium, γ-aminopropyltributoxytitanium, γ-aminoethyltriethoxytitanium , Γ-
Aminoethyltrimethoxytitanium, γ-aminoethyltripropoxytitanium, γ-aminoethyltributoxytitanium, γ-aminobutyltriethoxytitanium, γ-aminobutyltrimethoxytitanium, γ-aminobutyltripropoxytitanium, γ-aminobutyl And tributoxy titanium. The amount of the coupling agent as described above is preferably in the range of 0.5 to 5% by weight based on the polyamic acid resin.

The temperature at which the polyamide acid in the resin composition is dehydrated and ring-closed to form a polyimide resin film is 100 to 100.
The temperature can be arbitrarily selected in the range of 400 ° C, preferably 150 to 250 ° C. The heating time is usually 1 minute to 6 minutes.
Time, preferably 1 minute to 3 hours.

The protective film / alignment film for a liquid crystal of the present invention is prepared by printing the above resin composition on a glass substrate on which a transparent electrode such as ITO or a comb electrode is formed in advance, followed by drying and dehydration ring closure. A polyimide layer is obtained by rubbing the surface. As a film forming method, a polyimide film is preferably formed by a printing method that does not require a photolithography step and is easily patterned and formed.The resin composition is easy to hold, and the amount of transfer to a liquid crystal sandwiching substrate is large. Membrane production is more preferred. FIG. 8 shows a method of manufacturing a printing resin film using a flexographic printing machine. The resin composition necessary for printing is dropped from a dispenser 21 on the rotating doctor roll 22. The dropped resin composition is kneaded with two rolls to form a uniform liquid film on the anix roll 23. This liquid film is transferred to the plate pattern of the printing plate 25 on the plate cylinder 24, and the liquid film on the plate pattern is transferred onto the printing medium 26 passing below. At this time, the printing medium 26 is placed on the table 27, adjusted to an appropriate height by the table vertical mechanism 28, and moves in the direction of the arrow. Reference numeral 29 denotes a positioning image processing device. The liquid crystal display device of the present invention can be obtained by a known method using the substrate having the protective film and alignment film for liquid crystal of the present invention.

Next, the present invention will be described in more detail with reference to the drawings. FIG. 1 is an explanatory diagram of the operation of the liquid crystal in the liquid crystal display device of the present invention. 1 (a) and 1 (b) are side sectional views of a liquid crystal sandwiching substrate showing an operation of a liquid crystal in the liquid crystal display device of the present invention, and FIGS. 1 (c) and 1 (d) are liquid crystal sandwiching substrates having electrodes. FIG. The liquid crystal display device of the present invention
Generally, it is composed of a plurality of pixels, but here only one pixel portion is shown. FIG. 1 (a) is a side sectional view of the cell when no electric field is applied.
FIG. 1C shows a front view at that time.

A gate insulating film 3 is formed on a linear common electrode 2 inside a glass substrate 1, a signal electrode 4 and an image electrode 5 are formed thereon, and a liquid crystal protective film of the present invention is formed thereon. One of the liquid crystal sandwiching substrates is formed by forming the liquid crystal sandwiching substrate 6, and the liquid crystal protecting film and the alignment film 6 is formed on the substrate 1, and the other liquid crystal sandwiching substrate is formed. A polarizing plate 8 is laminated on the back surface of each liquid crystal holding substrate. In FIG. 1, the electrodes 2 and 5 are provided on one substrate, but may be provided on both substrates. The rod-shaped liquid crystal molecules 7 are used as the protective film and alignment film 6 for liquid crystal.
At the interface between both substrates, the alignment is controlled in the direction of arrow 9 having a slight angle in the longitudinal direction of the electrodes 2 and 5 (the front view of FIG. 1 (c)). It is almost uniformly oriented in this direction.
Here, different potentials are respectively applied to the pixel electrode 5 and the common electrode 2 by the driving means, and an electric field is applied to the liquid crystal composition layer in the direction of the arrow 10 due to the potential difference between them. Fig. 1
As shown in (b) and (d), the liquid crystal molecules change their directions in the direction of the electric field. At this time, the optical properties of the liquid crystal element change due to the refractive index anisotropy of the liquid crystal composition and the action of the polarizing plate 8. 1C and 1D, the gate insulating film is transparent and is not shown.

Next, the reason why the cell gap between the substrates particularly affects the luminance unevenness is that, as schematically shown in FIG. 2, when the voltage applied between the electrodes in the liquid crystal display device is changed, the display luminance is reduced. This is because a change occurs. That is, the liquid crystal display device has a thickness of 0.3 to 0.3 due to various electrodes formed on the substrate, thin film transistors, and unevenness of the color filter.
A fluctuation (± Δd) of the gap between substrates of about 1.0 μm occurs. Gap between the substrates, also particularly sensitive to the voltage [Delta] V ₅₀ which is half of the maximum luminance value of the change in ΔVc and display brightness threshold voltage when the center value d is changed ± [Delta] d, which is a factor that luminance unevenness occurs.

Therefore, in the present invention, unlike a conventional liquid crystal alignment film having a film thickness of 0.1 μm or less and a large weight average molecular weight, it is patterned by a printing method using a polyamic acid having a weight average molecular weight of 20,000 or less. After forming a film having a film thickness of 0.3 μm or more, a protective film for liquid crystal and an alignment film are formed by drying, dehydration ring closure, and rubbing, thereby flattening the unevenness of the substrate and using a small amount of spacer beads for controlling the cell gap. And the contrast of the liquid crystal display device can be greatly improved.

FIGS. 3 and 4 are cell cross-sectional views showing the dispersion state of spacer beads in the liquid crystal display devices of the prior art and the present invention, respectively. In FIG. 3, a black matrix 12 is formed on a glass substrate 1, a layer of a color filter 13 is further formed, and a color filter protective film 14 and a liquid crystal alignment film 15 are sequentially formed thereon to form one liquid crystal. A holding substrate is formed. Further, a common electrode 2 and a gate insulating film 3 are formed on a glass substrate 1, a pixel electrode 5 is further formed thereon, and an insulating protective film 16 and a liquid crystal alignment film 15 are sequentially formed to form the other liquid crystal. A holding substrate is formed. Liquid crystal is held between these liquid crystal holding substrates, and spacer beads 17 are distributed therein. In FIG. 4, a black matrix 12 is formed on a glass substrate 1 and a color filter 1 is formed.
3 is formed thereon, and a protective film / alignment film for a liquid crystal (a color filter protective film / liquid crystal alignment film) 6 according to the present invention is sequentially formed thereon to form one liquid crystal sandwiching substrate. . Further, a common electrode 2 and a gate insulating film 3 are formed on a glass substrate 1, a pixel electrode 5 is further formed thereon, and an insulating protective film 16 and a liquid crystal protective film and alignment film 6 according to the present invention are further formed. Are sequentially formed to form the other liquid crystal holding substrate. Liquid crystal is held between these liquid crystal holding substrates, and spacer beads 17 are distributed therein.

As is apparent from a comparison between FIG. 3 and FIG. 4, since the thickness of the liquid crystal protective film / alignment film of the present invention can be increased, the surface can be flattened and the spacer beads 17 can be formed. Can sufficiently fulfill its role even in small quantities. That is, a very small amount of spacer beads 1
7, the cell gap can be appropriately controlled and maintained.

[0034]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.

Synthesis Example 1 Isophthalodil dihydrazide 2.912 in a four-necked flask equipped with a thermometer, a stirrer, a condenser and a nitrogen inlet tube.
9 g (0.015 mol) and 7.5709 g (0.035 mol) of 4,4'-diaminodiphenyl sulfide
-Butyrolactone is dissolved in 30.586 g, and 1,2,3,4-butanetetracarboxylic dianhydride is added thereto.
9066 (0.05 mol) was added, and the mixture was stirred and reacted at room temperature for 8 hours to produce a polyamic acid. The obtained polyamic acid resin composition was heated at 130 ° C. for 1 hour.
The obtained resin composition had a solid content of 40% by weight, a viscosity of 220 mPa · s (25 ° C.), and a weight average molecular weight of polyamic acid (weight average molecular weight in terms of standard polystyrene, the same applies hereinafter) of 5,100. . Next, this total solid content 40
Weight% of a polyamic acid resin composition on a glass substrate
Spin coat at 0 rpm, 220 ° C for 10 minutes at 80 ° C
For 30 minutes to form a polyimide resin film having a thickness of 2.66 μm. About this polyimide resin film
When the light transmittance was measured with a spectrophotometer UL-3410 manufactured by Hitachi, Ltd., it showed a good transmittance of 96.0% or more at 400 to 800 nm.

Example 1 A glass substrate # 7059 (200 mm ×
(270 mm × 1.1 mm thick) are used. A matrix element including an amorphous silicon thin film transistor to which a horizontal electric field can be applied and a wiring electrode was formed on one substrate by a known method. The structures of the thin film transistor and various electrodes used here are shown in FIGS. FIG. 5 is a front view of the matrix element viewed from a direction perpendicular to the substrate surface, and FIG.
FIG. 7 is a sectional view taken along line BB of FIG. 5. The thin film transistor 18 includes a pixel electrode (source electrode) 5, a signal electrode (drain electrode) 4, a scanning electrode (gate electrode) 1
9 and amorphous silicon 20. The common electrode 2 and the scanning electrode 19 and the signal electrode 4 and the pixel electrode 5 were formed by patterning the same metal layer.
The pixel electrode 5 has three common electrodes 2 as shown in FIG.
It is located between. The pixel pitch was 100 μm in the horizontal direction (that is, between signal electrodes) and 300 μm in the vertical direction (that is, between scan electrodes). On the other hand, the widths of the pixel electrode and the common electrode extending in the longitudinal direction of the pixel electrode and the common electrode, which are independently formed in units of one pixel in order to improve the aperture ratio, are slightly reduced to 5 μm and 6 μm, respectively. The signal electrode 4 and the common electrode 2 were provided with an interval of 2 μm via an insulating film.
At this time, the number of pixels is 640 × 3 × 4 by 640 × 3 (R, G, B) signal wiring electrodes and 480 wiring electrodes.
80 pieces. The height of the electrode was 0.6 μm.

A resin composition obtained by adding 2% by weight of γ-aminopropyltriethoxysilane to the polyamic acid resin composition having a solid content of 40% by weight prepared in Synthesis Example 1 to the substrate with a thin film transistor thus prepared. Using the material, a resin film was formed by flexographic printing. condition is,
Anilox: 400 mesh, printing plate: 150 mm x 20
The thickness was 0 mm x 2.2 mm, 300% mesh, 30% (manufactured by Komura Seiki Co., Ltd.), an anis roll-plate nip width 7 mm, and a doctor roll-anix roll width 0.2 mm. The formed print film was heated at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film is extremely smooth, and a stylus-type film thickness measurement device (Solan
Technology Co. LTD., Dektak3030) showed a thickness of 3.0 μm, showing irregularities of 0.10 μm,
The steps have been reduced.

On the other glass substrate, carbon fine particles manufactured by Cabot Corporation (MONARCH80) were used as a light shielding layer.
0, a particle diameter of 16 nm) and 1% by weight of an epoxy resin, and PD-170 as a color filter coloring pigment.
(Hitachi Kasei Kogyo Co., Ltd., trade name), the width of the light shielding layer is 20 μm, the height is 0.52 μm, and one pixel is 80 μm.
A color filter in which pixels were arranged in stripes of three colors of red, green, and blue of 280 μm was produced. The solid content of 4 prepared in Synthesis Example 1 above was added to this color filter substrate.
A color filter protective film layer (polyimide film) was formed by flexographic printing using a resin composition in which 2% by weight of γ-aminopropyltriethoxysilane was added to a 0% by weight polyamic acid resin composition. As a result, the unevenness was 0.13 μm with respect to the film thickness of 3.0 μm, and the step was reduced.

The surface of the above polyimide film is subjected to a rubbing treatment (roll indentation 0.4 mm, roll rotation speed 600 rp).
m, the substrate moving speed was 420 mm / min, and rubbing was performed once) to obtain a liquid crystal sandwiching substrate as a protective film and an alignment film. After rubbing, the polyimide film did not peel off and showed good adhesion. The rubbing directions on the upper and lower interfaces were substantially parallel to each other, and the angle between the rubbing directions and the applied voltage direction was 85 degrees. This liquid crystal sandwiching substrate is combined, the periphery is sealed with a thermosetting adhesive Struct Bond XN-21-S (trade name, manufactured by Mitsui Toatsu Chemical Co., Ltd.), and after heating and curing at 150 ° C. for 1.5 hours, A liquid crystal cell was formed. At this time, in order to keep the gap of the liquid crystal cell constant, polymer beads having a diameter of 4.0 μm were interposed as spacers. Liquid crystal MLC-2027 (trade name, manufactured by Merck) was injected between the substrates by a vacuum impregnation method. To form a liquid crystal display element was heat-treated for 1 hour at 100 ° C. is a T _NI above the temperature of the liquid crystal MLC-2027. Then, two polarizing plates (GI220 manufactured by Nitto Denko Corporation)
D) sandwiched the panel, and set it as a normally-closed characteristic as orthogonal. When the characteristics were evaluated by modularization, the contrast ratio was sufficiently high at 100: 1, and non-uniformity of alignment, poor alignment such as reverse tilt domain, and display unevenness due to contamination of liquid crystal did not occur at all. In addition, luminance unevenness due to a gap defect was not visually recognized at all, and a display with high uniformity was obtained.

Synthesis Example 2 10.810 g of p-phenyldiamine in a four-necked flask equipped with a thermometer, a stirrer, a condenser and a nitrogen inlet tube
(0.10 mol), 24.830 g (0.10 mol) of 4,4'-diaminodiphenylsulfone, 3,3 ', 4,4
4'-biscyclohexanetetracarboxylic dianhydride 4
2.884 g (0.14 mol) and 31.350 g (0.06 mol) of decamethylene trimellitate dianhydride are dissolved in 439.496 g of N-methyl-2-pyrrolidone and stirred at room temperature for 8 hours. To produce a polyamic acid. 130 parts of the obtained polyamic acid resin composition
Heat treatment was performed at 1 ° C for 1 hour. The obtained resin composition had a solid content of 20% by weight, a viscosity of 78.6 mPa · s (25 ° C.), and a weight average molecular weight of the polyamic acid of 15,000. Next, this polyamic acid resin composition having a total solid content of 20% by weight was spin-coated on a glass substrate at 1000 rpm and heat-treated at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to form a 1.19 μm-thick polyimide film. Formed. The light transmittance of this polyimide film was measured in the same manner as in Example 1. As a result, good transmittance of 90.0% or more at 400 to 800 nm was shown.

Example 2 The polyamic acid resin composition having a solid content of 20% by weight prepared in Synthesis Example 2 was diluted with butyl cellosolve to a solid content of 15% by weight, and γ-aminopropyltriethoxysilane was added at 2% by weight of the resin. As a result, the viscosity was 25 mPa · s (2
5 ° C.). A film was formed by flexographic printing on the substrate with a thin-layer transistor manufactured in Example 1 using the polyamic acid resin composition having a solid content of 15% by weight thus manufactured under the same conditions as in Example 1. 80 ° C.
And cured at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film was extremely smooth, showing irregularities of 0.25 μm with respect to the film thickness of 0.72 μm, and the step was reduced. Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. The surface of the obtained polyimide film is extremely smooth, and the surface of the polyimide film has a thickness of 0.72 μm.
The unevenness was 28 μm, and the step was reduced.

Using these substrates, a liquid crystal display device was formed in the same manner as in Example 1, and the characteristics were evaluated by modularization. The contrast was 85: 1, and the contrast was sufficiently high. There was no display unevenness due to poor alignment such as a reverse tilt domain or reverse tilt domain, and contamination of liquid crystal. In addition, uneven brightness due to gap failure was not visually recognized, and a display with high uniformity was obtained.

Synthesis Example 3 3.029 g of 1,8-octyldiamine in a four-necked flask equipped with a thermometer, a stirrer, a cooling tube and a nitrogen inlet tube.
(0.021 mol) and 1.9468 g (0.009 mol) of 4,4'-diaminodiphenyl sulfide are dissolved in 25.479 g of γ-butyrolactone, and 1,2,3,4-butanetetracarboxylic acid is added thereto. Dianhydride5.
9440 g (0.03 mol) was added, and the mixture was stirred and reacted at room temperature for 8 hours to produce a polyamic acid. The obtained polyamic acid resin composition was heated at 130 ° C. for 1 hour. The obtained resin composition has a solid content of 30% by weight,
The viscosity was 116 mPa · s (25 ° C.), and the weight average molecular weight of the polyamic acid was 6,800. This polyamic acid resin composition having a solid content of 30% by weight was
Spin coating was performed at rpm, and heat treatment was performed at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to form a 1.86 μm-thick polyimide film. When the light transmittance of this polyimide film was measured in the same manner as in Example 1, the light transmittance was 400 to 800.
It showed good transmittance of 90.0% or more in nm.

Example 3 The polyamic acid resin composition having a solid content of 30% by weight prepared in Synthesis Example 3 was diluted with butyl cellosolve to a solid content of 25% by weight, and γ-aminopropyltriethoxysilane was added at 2% by weight of the resin. As a result, the viscosity became 35 mPa · s (2
5 ° C.). Using the polyamic acid resin composition having a solid content of 25% by weight thus manufactured, a film was formed on the substrate with a thin film transistor manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. 80
Curing was performed at 10 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film was extremely smooth, showing irregularities of 0.18 μm with respect to the film thickness of 1.53 μm, and the step was reduced. Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. The surface of the obtained polyimide film is extremely smooth, and the surface of the polyimide film has a thickness of 1.53 μm.
The unevenness was 22 μm, and the step was reduced.

Using these substrates, a liquid crystal display device was formed in the same manner as in Example 1, and the characteristics were evaluated by modularization. The contrast was sufficiently high at 90: 1, and the alignment was non-uniform. There was no display unevenness due to poor alignment such as a reverse tilt domain or reverse tilt domain, and contamination of liquid crystal. In addition, uneven brightness due to gap failure was not visually recognized, and a display with high uniformity was obtained.

Synthesis Example 4 2,4-Diaminodiphenyl ether 1 was placed in a four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet.
2.648 g (0.063 mol) and 2.2-bis (4
-Aminophenoxy) hexafluoropropane 14.0
76 g (0.042 mol) of γ-butyrolactone 140
g of oxydiphthalic dianhydride 3
1.026 g (0.1 mol) and 1,3-bis (3,4
2.244 g (0.0053 mol) of (-dicarboxyphenyl) tetramethyldisiloxane dianhydride was added, and the mixture was stirred and reacted at room temperature for 8 hours to produce a polyamic acid. The obtained polyamic acid resin composition was dried at 150 ° C. for 0.1 hour.
Heat treatment was performed for 5 hours. The resulting resin composition had a solid content of 30% by weight and a viscosity of 350 mPa · s (25 ° C.)
The weight average molecular weight of the polyamic acid was 18,000. The polyamic acid resin composition having a solid content of 30% by weight was spin-coated on a glass substrate at 1500 rpm, and heat-treated at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a film thickness of 1.7.
An 8 μm polyimide film was formed. The light transmittance of this polyimide film was measured in the same manner as in Example 1. As a result, good transmittance of 92.0% or more at 400 to 800 nm was shown.

Example 4 The polyamic acid resin composition having a solid content of 30% by weight prepared in Synthesis Example 4 was diluted with butyl cellosolve to a solid content of 20% by weight, and γ-aminopropyltriethoxysilane was added at 2% by weight of the resin. As a result, the viscosity became 45 mPa · s (2
5 ° C.). Using the polyamic acid resin composition having a solid content of 20% by weight thus produced, a film was formed on the substrate with a thin film transistor produced in Example 1 by flexographic printing under the same conditions as in Example 1. 80
Curing was performed at 10 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film was extremely smooth, showing irregularities of 0.22 μm with respect to the film thickness of 1.0 μm, and the step was reduced. Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. The surface of the obtained polyimide film is extremely smooth,
The unevenness was 4 μm, and the step was reduced.

Using these substrates, a liquid crystal display device was formed in the same manner as in Example 1, and the characteristics were evaluated by modularization. The contrast was sufficiently high at 90: 1, and the alignment was non-uniform. There was no display unevenness due to poor alignment such as a reverse tilt domain or reverse tilt domain, and contamination of liquid crystal. In addition, uneven brightness due to gap failure was not visually recognized, and a display with high uniformity was obtained.

Synthesis Example 5 Isophthalodil dihydrazide 4.975 in a four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet tube.
1 g (0.033 mol) and 1.903 g (0.01 mol) of 4,4'-diaminodiphenyl sulfide are dissolved in 19.116 g of N-methyl-2-pyrrolidone. 6.499 g (0.05 mol) of -butanetetracarboxylic dianhydride and 11.47 g of γ-butyrolactone were added, and the mixture was stirred and reacted at room temperature for 8 hours to produce a polyamic acid. The obtained polyamic acid resin composition was heated at 130 ° C. for 1 hour. The obtained resin composition had a solid content of 35% by weight and a viscosity of 118 mPa · s.
(25 ° C.), and the weight average molecular weight of the polyamic acid is
4800. When the polyamic acid resin composition having a solid content of 35% by weight was diluted with butyl cellosolve to a solid content of 30% by weight, the viscosity became 52 mPa · s (25 ° C.). The resin composition having a solid content of 30% by weight was spin-coated on a glass substrate at 1500 rpm and heat-treated at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to form a 1.7 μm-thick polyimide film. About this polyimide film,
When the light transmittance was measured in the same manner as in Example 1, it was 4
It showed good transmittance of 96.0% or more at 00 to 800 nm.

Example 5 When 2% by weight of γ-aminopropyltriethoxysilane was added to the polyamic acid resin composition having a solid content of 30% by weight prepared in Synthesis Example 5, the viscosity was 52 mPa · s (2
5 ° C.). Using the thus prepared polyamic acid resin composition having a solid content of 30% by weight, a film was formed on the substrate with a thin film transistor manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. 80
Curing was performed at 10 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film was extremely smooth, showing irregularities of 0.12 μm with respect to the film thickness of 2.0 μm, and the step was reduced. Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. The surface of the obtained polyimide film is extremely smooth and has a thickness of 2.0 μm and a thickness of 0.1 μm.
The unevenness was 4 μm, and the step was reduced.

Using these substrates, a liquid crystal display device was formed in the same manner as in Example 1, and the module was evaluated for characteristics. The contrast was sufficiently high at 100: 1, and the alignment was non-uniform. There was no display unevenness due to poor alignment such as a reverse tilt domain or reverse tilt domain, and contamination of liquid crystal. In addition, uneven brightness due to gap failure was not visually recognized, and a display with high uniformity was obtained.

Synthesis Example 6 26.628 g of p-phenylenediamine in a four-necked flask equipped with a thermometer, a stirrer, a condenser and a nitrogen inlet tube.
(0.20 mol), 31.701 g (0.16 mol) of 1,2,3,4-butanetetracarboxylic dianhydride and 20.90 g of decamethylene trimellitate dianhydride
(0.04 mol) with N-methyl-2-pyrrolidone 31
The polyamic acid varnish was prepared by dissolving in 6.92 g and stirring and reacting at room temperature for 8 hours. This polyamic acid varnish was heated at 80 ° C. for 1 hour. The resulting varnish had a solid content of 20% by weight and a viscosity of 200 mPa · s (25%).
° C), and the standard polystyrene-equivalent weight average molecular weight is
20,000. The varnish having a solid content of 20% by weight was spin-coated on a glass substrate at 1000 rpm, and heat-treated at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a film thickness of 1.7.
A μm polyimide film was formed. When the transmittance of this polyimide film was measured in the same manner as in Example 1, it showed good transmittance of 91.0% or more at 400 to 800 nm.

Example 6 The varnish of 20% by weight prepared in Synthesis Example 6 was diluted to 7% by weight with butyl cellosolve, and γ-aminopropyltriethoxysilane was added at 2% by weight of the resin, and the viscosity was 40 mPa · s ( 25 ° C). A resin film was formed on the TFT substrate manufactured in Example 1 by flexographic printing using the varnish having a total solid content of 7.1% by weight. Conditions are anilox: 400 mesh, resin plate: 150 mm
× 200 mm × 2.2 mm thick, 200 mesh 20% (manufactured by Komura Seiki Co., Ltd.), anilox roll to plate nip width 7
mm, doctor roll to anilox roll width 0.2 mm. The formed printing film was cured at 80 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film was extremely smooth and was measured with a stylus-type film thickness meter (Dektak 3030, manufactured by Solan Technology Co. LTD.).
And the step was reduced. Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1. The surface of the obtained polyimide film was extremely smooth, showing irregularities of 0.27 μm with respect to the film thickness of 0.3 μm, and the steps were reduced.

Using these substrates, a liquid crystal display element was formed in the same manner as in Example 1, and the characteristics were evaluated by modularization. The contrast was 95: 1, which was sufficiently high. There was no display unevenness due to poor alignment such as a reverse tilt domain or reverse tilt domain, and contamination of liquid crystal. In addition, uneven brightness due to gap failure was not visually recognized, and a display with high uniformity was obtained.

Synthesis Example 7 In a four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet tube, 10.012 g (0.05 mol) of 4,4'-diaminodiphenyl ether was added with N-methyl-2-methyl-2-phenyl-2-ether. It was dissolved in 83.712 g of pyrrolidone, and 10.906 g (0.05 mol) of pyromellitic dianhydride was added thereto, and the mixture was stirred at room temperature for 8 hours to be reacted to produce a polyamic acid. The obtained polyamic acid resin composition was heated to 130 ° C.
For 1 hour. The obtained resin composition had a solid content of 20% by weight, a viscosity of 105 mPa · s (25 ° C.), and a weight average molecular weight of the polyamic acid of 25,000. Next, when the polyamic acid resin composition having a solid content of 20% by weight was diluted with N-methyl-pyrrolidone to a solid content of 10% by weight, the viscosity became 15 mPa · s (25 ° C.). This resin composition having a solid content of 10% by weight was spin-coated on a glass substrate at 800 rpm, and then at 80 ° C. for 10 minutes.
Heat treatment was performed at 220 ° C. for 30 minutes to form a polyimide film having a thickness of 0.78 μm. When the light transmittance of this polyimide film was measured in the same manner as in Example 1, the light transmittance was 400
It showed a light transmittance of 48.0% or more in nm.

Comparative Example 1 When 2% by weight of γ-aminopropyltriethoxysilane was added to the polyamic acid resin composition having a solid content of 10% by weight prepared in Synthesis Example 7, the viscosity was 15 mPa · s (2
5 ° C.). Using the polyamic acid resin composition having a solid content of 10% by weight thus produced, a film was formed on the substrate with a thin film transistor produced in Example 1 by flexographic printing under the same conditions as in Example 1. 80
Curing was performed at 10 ° C. for 10 minutes and at 220 ° C. for 30 minutes to obtain a polyimide film. The surface of the obtained polyimide film lacks uniformity,
The irregularities of 0.42 μm were shown for the film thickness of 0.2 μm.
Further, a film was formed on the color filter substrate manufactured in Example 1 by flexographic printing under the same conditions as in Example 1.
The surface of the obtained polyimide film lacks uniformity, and the thickness of the polyimide film is 0.
For 2 μm, irregularities of 0.4 μm were shown.

Using these substrates, a liquid crystal display device was formed in the same manner as in Example 1, and the characteristics were evaluated by modularization. As a result, poor alignment due to domains and display unevenness were observed, and a display with high uniformity was obtained. Was not obtained.

[0058]

The protective film / alignment film for liquid crystal according to claims 1 to 7 has good properties such as heat resistance, chemical resistance, adhesion to a glass substrate and a color filter, transparency, flatness, and printability. And has excellent orientation, and can easily be printed on a substrate by a printing method without a photolithography step.
It can be formed by patterning with a film thickness of. Since the liquid crystal sandwiching substrate according to claim 8 has no steps such as a color filter, a thin film transistor, a common electrode, a signal electrode, and a scanning electrode, the substrate is flat or flat, and an alignment defect domain caused by unevenness of the substrate, a contrast ratio, The aperture ratio is improved. Since the liquid crystal display device according to the ninth aspect exhibits good flatness characteristics, the driving voltage loss of the liquid crystal can be suppressed, and a large screen can be obtained by flattening the uneven structure of the substrate to uniform the cell gap. The effect on fineness and high-speed response is achieved, and good liquid crystal alignment can be obtained by one-step application, so that cost reduction can be achieved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of an operation of a liquid crystal in a liquid crystal display device.

FIG. 2 is a schematic diagram illustrating electro-optical characteristics of a liquid crystal display device.

FIG. 3 is a cell cross-sectional view showing a dispersion state of spacer beads in a conventional liquid crystal display device.

FIG. 4 is a cell cross-sectional view showing a dispersion state of spacer beads in the liquid crystal display device of the present invention.

FIG. 5 is a front view of the matrix element viewed from a direction perpendicular to the substrate surface.

FIG. 6 is a sectional view taken along line AA of FIG. 5;

FIG. 7 is a sectional view taken along line BB of FIG. 5;

FIG. 8 is an explanatory diagram of a method for manufacturing a protective film and an alignment film for a liquid crystal of the present invention using a flexographic printing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Common electrode 3 Gate insulating film 4 Signal electrode 5 Pixel electrode 6 Protective film and alignment film for liquid crystal 7 Liquid crystal molecules 8 Polarizing plate 11 Polarizing plate Polarization transmission axis direction 12 Black matrix 13 Color filter 14 Color filter protective film 15 Liquid crystal alignment Film 16 Insulating protective film 17 Spacer beads 18 Thin film transistor 19 Scanning electrode 20 Amorphous silicon 21 Dispenser 22 Doctor roll 23 Anix roll 24 Plate cylinder 25 Printing plate 26 Printed object 27 Table 28 Table up / down mechanism 29 Positioning image processing device

Continued on the front page (72) Inventor Yasuo Katsuya 4-3-1-1, Higashicho, Hitachi City, Ibaraki Prefecture Inside the Hitachi Chemical Co., Ltd. Yamazaki Plant (72) Takao Nakagawa 4-3-1-1, Higashicho, Hitachi City, Hitachi, Hitachi Hitachi (72) Inventor Toyoichi Ueda 4-9-25 Shibaura, Minato-ku, Tokyo Hitachi Chemical Industry Co., Ltd. (72) Hiroyuki Umeda 7-1-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd.Hitachi Research Laboratories (72) Katsumi Kondo Inventor 7-1-1, Omikacho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd.Hitachi Research Laboratory Co., Ltd. 1-1 Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Hisao Yokokura 7-1-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi Research Laboratory

Claims (9)

[Claims] (1) a weight average molecular weight of 1,000 to 20,000
A liquid film made of a resin composition containing polyamic acid,
A protective film and alignment film for liquid crystal, comprising a polyimide film formed by printing on the surface of the liquid crystal sandwiching substrate on which the electrodes are formed, and formed by heating and drying. 2. The protective film for a liquid crystal according to claim 1, wherein the resin composition containing a polyamic acid contains a solvent so that the solid content concentration is 7 to 60% by weight, and the viscosity is 30 to 1000 mPa · s. Alignment film. 3. A polyamic acid comprising: (a) a rigid diamine compound having a benzene ring, (b) a rigid dihydrazide compound having a benzene ring, and (c) a diamine compound having a sulfone group and / or a sulfide group. 3. The protective film and alignment film for a liquid crystal according to claim 1, wherein the diamine component containing at least one compound selected from the group and a tetracarboxylic dianhydride component are reacted. 4. A compound selected from the group consisting of (a) a rigid diamine compound having a benzene ring, (b) a rigid dihydrazide compound having a benzene ring, and (c) a diamine compound having a sulfone group and / or a sulfide group. 4. The protective film and alignment film for liquid crystal according to claim 3, wherein the total amount of the compound is 30 mol% or more of the total number of moles of the diamine component. 5. The tetracarboxylic dianhydride component contains an aliphatic tetracarboxylic dianhydride and / or an alicyclic tetracarboxylic dianhydride in an amount of 30 mol% or more of the total number of moles of the acid dianhydride component. The liquid crystal protective film and alignment film according to claim 3. 6. A tetracarboxylic dianhydride having the general formula (I): ## STR1 ## [Wherein n represents an integer of 2 to 20], wherein the tetracarboxylic dianhydride is represented by 2
4. The protective film and alignment film for liquid crystal according to claim 3, which contains 0 mol% or more. 7. The protective film and alignment film for a liquid crystal according to claim 2, wherein the solvent contains a lactone-based solvent in an amount of 30% by weight or more of the total weight of the solvent. 8. A liquid crystal sandwiching substrate having the liquid crystal protective film and alignment film according to claim 1. 9. An electrode is provided on the liquid crystal sandwiching substrate on the side facing the liquid crystal, and the protective film and alignment film for liquid crystal according to claim 1 is provided on the substrate and the electrode. Liquid crystal display device.