JP5286773B2 - Color filter - Google Patents

Description

  The present invention relates to a color filter used in a vertical alignment liquid crystal display device.

  In a liquid crystal display device, a transparent substrate on the color filter side and a liquid crystal driving side substrate are opposed to each other, and a liquid crystal compound is sealed between the two to form a thin liquid crystal layer, and the liquid crystal driving side substrate forms a liquid crystal array in the liquid crystal layer. Display is performed by selectively changing the amount of transmitted or reflected light of the color filter under electrical control.

  In recent years, there has been proposed a vertical alignment liquid crystal display device in which liquid crystal molecules are arranged perpendicular to a substrate surface in a state where no voltage is applied, and the liquid crystal molecules are tilted in various directions when a voltage is applied. This vertical alignment liquid crystal display device is superior in terms of contrast ratio, response speed, and the like as compared with a twisted nematic liquid crystal display device conventionally used. In addition, when the direction in which the liquid crystal molecules are tilted is set to a large number of directions, there is an advantage that a wide viewing angle can be effectively realized.

  As a vertical alignment liquid crystal display device in which the liquid crystal is tilted in many directions, for example, as shown in FIG. 2, the second electrode layer 11 formed on the transparent electrode layer 3 and the opposite liquid crystal driving side substrate 12 is used. A method of forming the liquid crystal alignment control protrusions 4 on the surface and controlling the alignment direction of the liquid crystal 13 when a voltage is applied (hereinafter also referred to as MVA method) has been proposed (for example, Patent Document 1). .

  Here, a positive resist is usually used to form the liquid crystal alignment control protrusion. When a negative resist is used, when a voltage is applied to the liquid crystal display device and then the voltage is removed, the orientation of the liquid crystal around the liquid crystal alignment control protrusion is difficult to return to the same direction as before the voltage application, i.e. This is because there will be a dullness. This is presumed to occur due to the short distance between the cross-linking points in the negative resist and the difficulty in escape of electrons and ions generated when a voltage is applied from the characteristics of the resin used. In addition, it has been confirmed that the above-mentioned burn-in hardly occurs in a commonly used positive resist.

  However, when a positive resist is used, there is a problem in that the liquid crystal alignment control protrusions cannot be formed with high definition at the target height. This is because when the liquid crystal alignment control protrusion is formed, the area where the liquid crystal alignment control protrusion is formed is exposed due to the influence of light wrapping (diffraction), and the positive resist is dissolved by the developer. This is due to the fact that When a positive resist is used when manufacturing a large-area liquid crystal display device, the liquid crystal alignment control protrusions are formed so that the height of the liquid crystal alignment control protrusions is uniform over the entire area of the color filter. There was also a problem that it was difficult. This is because, when a color filter used in a large-area liquid crystal display device is manufactured, the photomask used when patterning the liquid crystal alignment control protrusions may bend, and the distance between the resist and the photomask is constant. Not. For this reason, a region where the influence of light sneak (diffraction) is large and a region where the influence of light sneak (diffraction) is small are generated.

  Furthermore, since other members such as a colored layer and columnar spacers of a general color filter are formed using a negative resist, when a positive resist is used as a liquid crystal alignment control protrusion forming composition, When forming the liquid crystal alignment control protrusions, a step of changing the developer is required, and there is a problem that the production efficiency of the color filter is poor.

JP 2003-75839 A

  Accordingly, it is desired to provide a color filter having a high-quality liquid crystal alignment control protrusion with a uniform height that hardly causes burn-in or the like when used in a liquid crystal display device.

  The present invention is formed in a region corresponding to the transparent substrate, the colored layer formed on the transparent substrate, the transparent electrode layer formed on the colored layer, and the colored layer on the transparent electrode layer. A liquid crystal alignment control protrusion, wherein the liquid crystal alignment control protrusion has a six-membered ring structure of one or two kinds of atoms, and three unsaturated bonds are included in the six-membered ring structure. And a polymer having a unit in which at least one atom adjacent to the six-membered ring structure is an oxygen atom or a nitrogen atom.

  According to the present invention, the π-electron bond of the polymer can easily pass electrons generated when the liquid crystal alignment control protrusion is used in a liquid crystal display device, and therefore, it is difficult for image sticking to occur. Can do.

  Moreover, it is preferable that the polymer contained in the liquid crystal alignment control protrusion is a phenol novolac acid-modified resin represented by the following general formula (1).

（式（１）中、Ｒ^１、Ｒ^２、およびＲ^３はそれぞれ、ＯＨ基、またはカルボキシル基を末端に有する下記一般式（１−１）で表される基を示し、Ｒ^１、Ｒ^２、およびＲ^３のうち、少なくとも１つが下記一般式（１−１）で表される基とされる。ｎは１以上の整数である。）

(In the formula (1), R ¹ , R ² , and R ³ each represent a group represented by the following general formula (1-1) having an OH group or a carboxyl group at the end, and R ¹ , R ² And at least one of R ³ is a group represented by the following general formula (1-1), n is an integer of 1 or more.)

(In Formula (1-1), R ⁴ is
H, (CH ₂ ) _α , (CH) _α , C ₆ H ₄ , (C ₆ H ₂ )-(COOH) ₂
Any one of the groups represented by Α is an integer in the range of 1-6. )

  By using the phenol novolac acid-modified resin, it is possible to easily pass electrons generated when the protrusion for controlling liquid crystal alignment is used in a liquid crystal display device by π-electron bonding, and it is difficult for image sticking to occur. Because you can. In addition, the phenol novolac acid-modified resin has a carboxylic acid in its structure and can be used as a negative resist.

  In the said invention, it is preferable that the said liquid crystal orientation control protrusion is formed with the negative resin composition. This is because the liquid crystal alignment control protrusions can be efficiently formed so that the height is uniform over the entire area of the color filter.

  In the above invention, the absolute value of the residual DC of the liquid crystal alignment control protrusion is preferably 500 mV or less. Since there is a correlation between the absolute value of the residual DC of the liquid crystal alignment control protrusion and the burn-in that occurs when the liquid crystal display device is formed, the absolute value of the residual DC is made not more than the above value. This is because when the color filter is used in a liquid crystal display device, it is possible to prevent image sticking from occurring in the vicinity of the liquid crystal alignment control protrusion.

  According to the present invention, it is possible to obtain a color filter having a high-quality liquid crystal alignment control protrusion with a uniform height that hardly causes burn-in or the like when used in a liquid crystal display device.

  The present invention relates to a color filter used in a vertical alignment liquid crystal display device. The color filter of the present invention includes a transparent substrate, a colored layer formed on the transparent substrate, a transparent electrode layer formed on the colored layer, and a region corresponding to the colored layer on the transparent electrode layer. A liquid crystal alignment control protrusion formed, wherein the liquid crystal alignment control protrusion has a six-membered ring structure of one or two kinds of atoms, and three in the six-membered ring structure It contains a polymer having a unit containing an unsaturated bond and having at least one atom adjacent to the six-membered ring structure being an oxygen atom or a nitrogen atom.

  The color filter of the present invention includes, for example, as shown in FIG. 1, a transparent substrate 1, a colored layer 2 formed on the transparent substrate 1, a transparent electrode layer 3 formed on the colored layer 2, and the above It has a liquid crystal alignment control protrusion 4 formed in a region corresponding to each colored layer 2 on the transparent electrode layer 3. Note that the liquid crystal alignment control protrusions 4 are formed in the regions corresponding to the colored layers 2 on the transparent electrode layer 3, indicating that the colored layers 2 and the liquid crystal alignment controls are sandwiched between the transparent electrode layers 3. It means that the projection 4 is formed so as to correspond.

In general, it is known that a film containing a polymer having many π-electron bonds in its structure is likely to cause electron conduction. In the present invention, since the polymer contained in the liquid crystal alignment control protrusion has many π-electron bonds in the structure, when the liquid crystal alignment control protrusion is used in a liquid crystal display device, The generated electrons can be easily passed. Therefore, in the liquid crystal display device using the color filter of the present invention, it is possible to prevent image sticking from occurring in the vicinity of the liquid crystal alignment control protrusion.
Hereinafter, each configuration of the color filter of the present invention will be described in detail.

1. First, the liquid crystal alignment control protrusion used in the present invention will be described. The liquid crystal alignment control protrusion used in the present invention contains a polymer having a predetermined structure, and is formed on the transparent electrode layer described later so as to correspond to the colored layer described later. In the present invention, the liquid crystal alignment control protrusions may be formed of a negative resin composition or may be formed of a positive resin composition. It is preferably formed of a resin composition of a mold. By forming the projection for controlling liquid crystal alignment using a negative resin composition, the projection for controlling liquid crystal alignment is formed even when exposure light wraps around (diffraction) or the like occurs during patterning. Since the composition for forming the protrusions for controlling the alignment of the liquid crystal in the region does not dissolve in the developer, the liquid crystal alignment control protrusions to be formed do not vary in height, and the liquid crystal is uniformly formed over the entire color filter. This is because it is possible to form alignment control protrusions. Furthermore, it is possible to make the liquid crystal alignment control protrusion fine and to form the liquid crystal alignment control protrusion with a uniform height on a large-area color filter.

  Here, specifically, the polymer contained in the liquid crystal alignment control protrusion has a six-membered ring structure of one or two kinds of atoms, and three unsaturated bonds are included in the six-membered ring structure. And at least one atom adjacent to the six-membered ring structure has an oxygen atom or a nitrogen atom. Examples of the atoms constituting the 6-membered ring structure include a carbon atom and a nitrogen atom. The 6-membered ring shape only needs to contain either a carbon atom or a nitrogen atom. In the present invention, the atom adjacent to the 6-membered ring structure is preferably an oxygen atom. This is because, when the color filter of the present invention is used in a liquid crystal display device, it is possible to prevent image sticking from occurring in the vicinity of the liquid crystal alignment control protrusion.

  In addition, the polymer preferably has about 1 to 100 units, more preferably about 1 to 75 units, and more preferably about 1 to 50 units per molecule. This is because the liquid crystal alignment control protrusion can easily pass electrons generated when used in the liquid crystal display device. Furthermore, the weight average molecular weight of the polymer is preferably in the range of 500 to 10,000, more preferably in the range of 500 to 7500, and particularly preferably in the range of 500 to 5000. When the weight average molecular weight is larger than the above range, the viscosity becomes high and the coating property may be deteriorated. Further, if the weight average molecular weight of the polymer is smaller than the above range, the polymer may flow out during exposure and development.

  The weight average molecular weight is a value measured using tetrahydrofuran (THF) as a solvent using a gel permeation chromatograph (HLC-8220GPC manufactured by Tosoh Corporation). Moreover, it shall convert using polystyrene as a molecular weight standard substance.

  In the present invention, the polymer is preferably contained in the liquid crystal alignment control protrusions in an amount of about 1% by weight to 60% by weight, especially about 5% by weight to 50% by weight. This is because, when the liquid crystal alignment control protrusion is formed, it is possible to reduce the occurrence of burn-in. Further, when the amount is larger than the above amount, the curability of the liquid crystal alignment control protrusion is lowered, and the plate-making property may be deteriorated.

  Specific examples of the polymer having the unit include a phenol novolac acid-modified resin, a photocurable melamine resin, and a phenol-containing acrylic copolymer resin. In the present invention, among them, a phenol novolac acid-modified resin is preferable. The phenol novolac acid-modified resin is represented by the following general formula (1), and is obtained by acid-modifying a phenol novolac resin.

(In the formula (1), R ¹ , R ² , and R ³ each represent a group represented by the following general formula (1-1) having an OH group or a carboxyl group at the end, and R ¹ , R ² , And R ³ , at least one is a group represented by the following general formula (1-1), n is an integer of 1 or more, among which n is in the range of 2 to 50, particularly 2 to 30. It is preferable to be within the range.)

(In Formula (1-1), R ⁴ is
H, (CH ₂ ) _α , (CH) _α , C ₆ H ₄ , (C ₆ H ₂ )-(COOH) ₂
Any one of the groups represented by Α is an integer in the range of 1-6. )

The phenol novolak acid-modified resin is dissolved in a developer because the OH group of the phenol novolac resin is substituted with a group having a carboxyl group at the terminal (a group represented by the general formula (1-1)). And can be used for negative resists. Among the groups represented by the general formula (1-1), in the present invention, R ⁴ is preferably C ₆ H ₄ , (C ₆ H ₂ ) — (COOH) ₂ , and particularly C ₆ H _4. It is preferable that

In the present invention, it is preferable that one or two of R ¹ , R ² and R ³ are groups other than the OH group.

  The phenol novolak acid-modified resin can be produced by heating and reacting a novolak resin such as a phenol novolak resin or a cresol novolak resin with a carboxylic acid anhydride in the presence of a metal catalyst.

  On the other hand, when the liquid crystal alignment control protrusion is formed using a negative resist, in addition to the polymer described above, examples of the material used for forming the liquid crystal alignment control protrusion include resins such as polymers and monomers, light Examples thereof include a polymerization initiator, a surfactant, an adhesion assistant, and a solvent. As such materials, the same materials as those used for general negative resists can be used.

  Here, in the present invention, the absolute value of the residual DC is 500 mV or less, particularly 400 mV or less, particularly 300 mV, when the residual DC of the liquid crystal alignment control protrusion having the polymer is measured under the following conditions by the flicker erasing method. The following is preferable. It has been confirmed that there is a correlation between the absolute value of the residual DC of the liquid crystal alignment control protrusion and the image sticking generated in the liquid crystal display device. Specifically, when the absolute value of the residual DC of the liquid crystal alignment control protrusion is low, the liquid crystal display device using the liquid crystal alignment control protrusion is less burned, and the residual DC of the liquid crystal alignment control protrusion is less. When the absolute value is high, the liquid crystal display device using the liquid crystal alignment control protrusion is often burned. Therefore, by setting the residual DC of the liquid crystal alignment control protrusion to be equal to or less than the above value, when the color filter is used in a liquid crystal display device, image sticking is less likely to occur in the vicinity of the liquid crystal alignment control protrusion. Because it can. As the residual DC measuring device, a device having a halogen light source, a photoelectric conversion element, an arbitrary waveform generator, and an oscilloscope is used. Specifically, the aging process is performed by applying AC 5V to the measurement cell. At this time, the measurement temperature is 23 ° C., the electrode distance is 5 μm, and the applied voltage pulse frequency is 60 Hz. Thereafter, a voltage in a halftone display state is applied, and flicker is read from the transmitted light. An offset voltage is applied so as to eliminate the flicker, and the value of the applied voltage is set as a residual DC. In the measurement cell, only a liquid crystal alignment control protrusion is formed on a transparent substrate with a film thickness of 1.2 μm and a line width of 11 μm.

  The height of the liquid crystal alignment control protrusion is appropriately selected according to the use of the color filter and the like, but is usually about 8 μm to 14 μm, and more preferably about 9 μm to 12 μm. The line width of the liquid crystal alignment control protrusion is also selected as appropriate, and is usually about 0.8 μm to 1.6 μm, and more preferably about 1.0 μm to 1.4 μm. Thereby, when the color filter of the present invention is used in a liquid crystal display device, the liquid crystal alignment control protrusion can control the alignment direction of the liquid crystal satisfactorily. The shape of the liquid crystal alignment control protrusion is appropriately selected according to the type of the liquid crystal display device, and may be, for example, a cone shape or a pyramid shape, or may be a truncated cone shape or a truncated pyramid shape.

  The method for forming the liquid crystal alignment control protrusion is appropriately selected depending on the type of material used for forming the liquid crystal alignment control protrusion, and can be usually formed by a photolithography method.

2. Next, the colored layer used in the present invention will be described. The colored layer used in the present invention usually includes three colors of red, green, and blue, but in the present invention, for example, four or more colors may be included.

  Further, the shape and arrangement of the colored layer used in the present invention are not particularly limited, and may be a known arrangement such as a stripe type, a mosaic type, a triangle type, a four-pixel arrangement type, and the colored area is It can be set arbitrarily.

  Moreover, the formation method of the colored layer used for this invention is not specifically limited, The pigment dispersion method etc. which are used in the case of manufacture of the colored layer of a general color filter can be used. In addition, the material of the colored layer used in the present invention can be the same as that of the colored layer used in a general color filter, and thus detailed description thereof is omitted here.

3. Transparent electrode layer Next, the transparent electrode layer used for the color filter of this invention is demonstrated. The transparent electrode layer used in the color filter of the present invention can be the same as the transparent electrode layer used in a general color filter. For example, indium tin oxide (ITO), zinc oxide (ZnO), tin oxide ( It can be formed by a general film forming method such as a sputtering method, a vacuum vapor deposition method, a CVD method, etc. using SnO) and the like and alloys thereof. The thickness of such a transparent electrode layer can usually be about 0.01 μm to 1 μm.

4). Transparent substrate Next, the transparent substrate used in the present invention will be described. The transparent substrate used in the present invention is not particularly limited as long as the colored layer can be formed. As such a transparent substrate, for example, an inflexible transparent rigid material such as quartz glass, Pyrex (registered trademark) glass, or synthetic quartz plate, or a flexible resin film such as a transparent resin film or an optical resin plate is used. A transparent flexible material can be used.

5. Color filter The color filter of the present invention is not particularly limited as long as it has the transparent substrate, the colored layer, the transparent electrode layer, and the liquid crystal alignment control protrusion, and depends on the type of the liquid crystal display device used. The configuration is appropriately selected. For example, the light-shielding portion may be formed between the colored layer and the colored layer. Further, when the color filter of the present invention is used for a transflective liquid crystal display device, it is between the colored layer and the transparent substrate in the region to be the reflected light region, or between the colored layer and the transparent electrode layer, etc. A transparent resin layer or the like for adjusting the cell gap or the like may be provided. Such a light shielding part, a transparent resin layer, and the like can be the same as those used for a general color filter or a color filter for a transflective liquid crystal display device.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be specifically described with reference to examples.

[Example 1]
(Production of color filter)
As the substrate, a glass substrate (Corning 1737 glass) having a size of 300 mm × 400 mm and a thickness of 0.7 mm was prepared. After this substrate was washed according to a conventional method, a chromium thin film (thickness: 1000 mm) was formed on the entire surface of one side of the substrate by sputtering. A negative photosensitive resist (CFPR DN-83, manufactured by Tokyo Ohka Kogyo Co., Ltd.) is applied onto the chrome thin film, and exposed, developed, and heat-treated through a predetermined mask to form a black matrix pattern having a line width of 20 μm and a pitch of 100 μm. Formed.
Next, a negative photosensitive resin composition for a red pattern, a negative photosensitive resin composition for a green pattern, and a negative photosensitive resin composition for a blue pattern having the following compositions were prepared.

<Negative photosensitive resin composition for red pattern>
・ Red pigment (Chromophthal Red A2B manufactured by Ciba Specialty Chemicals)
4.8 parts by weight / yellow pigment (PASFOL Yellow D1819, manufactured by BASF) 1.2 parts by weight / dispersant (Disperbic 161, manufactured by Big Chemie) 3.0 parts by weight / monomer (SR399, manufactured by Sartomer) 4.0 weight Part / Polymer I 5.0 parts by weight / Initiator (Irgacure 907 manufactured by Ciba Specialty Chemicals)
1.4 parts by weight / initiator (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole) 0.6 parts by weight / solvent ( Propylene glycol monomethyl ether acetate) 80.0 parts by weight <negative photosensitive resin composition for green pattern>
Green pigment (Avisia Monastral Green 9Y-C) 4.2 parts by weight Yellow pigment (BASF Paliotor Yellow D1819) 1.8 parts by weight Dispersant (Bicchemy Disperbic 161) 3.0 Part by weight / monomer (SR399, manufactured by Sartomer) 4.0 part by weight / Polymer I, 5.0 parts by weight / initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals)
1.4 parts by weight / initiator (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole) 0.6 parts by weight / solvent ( Propylene glycol monomethyl ether acetate) 80.0 parts by weight <negative photosensitive resin composition for blue pattern>
Blue pigment (BASF Heliogen Blue L6700F) 6.0 parts by weight Pigment derivative (Abyssia Solsperse 5000) 0.6 parts by weight Dispersant (Bic Chemie Dispersic 161) 2.4 parts by weight Monomer (SR399, manufactured by Sartomer) 4.0 parts by weight, Polymer I, 5.0 parts by weight, initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals)
1.4 parts by weight / initiator (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole) 0.6 parts by weight / solvent ( Propylene glycol monomethyl ether acetate) 80.0 parts by weight The above polymer I is benzyl methacrylate: styrene: acrylic acid: 2-hydroxyethyl methacrylate = 15.6: 37.0: 30.5: 16.9 (mol) Ratio) is obtained by adding 16.9 mol% of 2-methacryloyloxyethyl isocyanate to 100 mol% of the copolymer, and the weight average molecular weight is 42500.

Next, a negative photosensitive resin composition for red pattern is applied by spin coating so as to cover the black matrix on the glass substrate, exposed and developed through a photomask for red pattern, and the red pattern is formed. Formed. The red pattern was rectangular (100 μm × 300 μm).
Then, the green pattern and the blue pattern were formed by the same operation using the negative photosensitive resin composition for the green pattern and the negative photosensitive resin composition for the blue pattern. As a result, a colored layer in which a red pattern, a green pattern, and a blue pattern were arranged was formed.
Next, a transparent electrode layer (thickness 1500 mm) made of indium tin oxide (ITO) was formed by sputtering so as to cover the black matrix and the colored layer.

Next, a resin composition for forming a protrusion for controlling liquid crystal alignment having the following composition was prepared.
<Synthesis of phenol novolac acid-modified resin I>
To the flask, 15 parts by weight of cresol novolac resin (EP-4080G manufactured by Asahi Organic Materials Co., Ltd.) and 85 parts by weight of cyclohexanone were added and stirred. After confirming uniform dissolution, the mixture was heated to 60 ° C., 0.2 parts by weight of trimethyltin laurate was added as a catalyst, and 1 part by weight of phthalic anhydride was further added to react for 3 hours. Thereafter, phenol novolac acid-modified resin I was obtained by adjusting with cyclohexanone so that the resin concentration was 20% by weight. The weight average molecular weight was 4500.

<Resin composition for forming protrusions for controlling liquid crystal alignment>
-25 parts by weight of the above phenol novolak acid-modified resin I-Dipentaerythritol hexaacrylate EO-modified product (DPT-25E manufactured by Toho Chemical Industry)
8 parts by weight, photo-curable melamine resin (Nikarak MX-302, manufactured by Sanwa Chemical Co., Ltd.) 3 parts by weight, initiator (Irgacure 907, manufactured by Ciba Specialty Chemicals) 1.4 parts by weight, initiator (2, 2 ' -Bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'-biimidazole) 0.6 parts by weight / solvent (propylene glycol monomethyl ether acetate) 62.0 parts by weight

Next, the liquid crystal alignment control protrusion forming resin composition was applied onto the transparent electrode layer by a spin coating method, and exposed and developed through a photomask to form liquid crystal alignment control protrusions.
Thereafter, a photosensitive resin composition for cell gap holding spacer pattern (Optomer NN780 manufactured by JSR Co., Ltd.) is applied on the transparent electrode layer by a spin coating method, exposed and developed through a photomask, and spacers are formed. A pattern was formed. This pattern had a dot shape (lower bottom 30 μmφ, height 3.5 μm). Next, an alignment film made of polyimide was formed on the transparent electrode layer on the surface of the color filter formed as described above. Thereafter, a required amount of vertical alignment liquid crystal is dropped on the glass substrate on which the TFT is formed, and then the color filter formed as described above is overlaid, and 0.3 kgf / cm ^{2 at} room temperature using a UV curable resin as a sealing material. A cell was produced by bonding at a dose of 400 mJ / cm ² while applying a pressure of ² to produce a cell, and a polarizing plate was attached to the upper and lower portions of the cell so that the polarization axis was 90 degrees to obtain a liquid crystal cell. .

[Example 2]
A liquid crystal cell was produced in the same manner as in Example 1 except that the following composition was used as the resin composition for forming a protrusion for controlling liquid crystal alignment.
<Resin composition for forming protrusions for controlling liquid crystal alignment>
・ Phenol novolac modified resin I 20 parts by weight ・ Phenol-containing acrylic copolymer resin (4-hydroxyphenyl acrylate / methyl methacrylate / acrylic acid) MW: 15000 3 parts by weight ・ Dipentaerythritol hexaacrylate EO modified product (Toho Chemical) Industrial DPT-25E)
10 parts by weight initiator (Ciba Specialty Chemicals Irgacure 907) 1.4 parts by weight initiator (2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl -1,2'-biimidazole) 0.6 parts by weight / solvent (propylene glycol monomethyl ether acetate) 65.0 parts by weight

[Comparative Example 1]
A liquid crystal cell was produced in the same manner as in Example 1 except that the following composition was used as the resin composition for forming a protrusion for controlling liquid crystal alignment.
<Resin composition for forming protrusions for controlling liquid crystal alignment>
Acrylic copolymer resin (benzyl methacrylate / methyl methacrylate / acrylic acid) MW: 15000 10 parts by weight Monomer (SR399 manufactured by Sartomer) 4.0 parts by weight Initiator (Irgacure 907 manufactured by Ciba Specialty Chemicals) 1.4 parts by weight / initiator (2,2′-bis (o-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole) 0.6 parts by weight / solvent ( 84.0 parts by weight of propylene glycol monomethyl ether acetate)

[Evaluation]
The dimensions of the liquid crystal alignment control protrusions of the color filter produced as described above were measured with an optical microscope. The measurement results are shown in Table 1. In addition, when the protrusion for liquid crystal orientation control of the produced color filter was uniform, it was set as (circle).
Further, the residual DC of each liquid crystal cell was measured by the flicker elimination method described above. Further, Table 1 shows the result of visual evaluation of image sticking when a predetermined picture element pattern is energized and displayed in each liquid crystal cell at 60 Hz and AC 5 V and then black is displayed. The burn-in evaluation was ◎ if the time until the pixel pattern disappeared was ◎, で あ れ ば if it was within 10 minutes, and × otherwise.

  As in Example 1 and Example 2, when the phenol novolac acid-modified resin was included in the liquid crystal alignment control protrusion, it was possible to make it difficult for image sticking to occur.

It is a schematic sectional drawing for demonstrating the color filter of this invention. It is a schematic sectional drawing for demonstrating a general liquid crystal display device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Colored layer 3 ... Transparent electrode layer 4 ... Protrusion for liquid crystal orientation control

Claims (3)

Liquid crystal alignment control formed in a transparent substrate, a colored layer formed on the transparent substrate, a transparent electrode layer formed on the colored layer, and a region corresponding to the colored layer on the transparent electrode layer A color filter having protrusions,
The liquid crystal alignment control protrusion contains a phenol novolac acid-modified resin represented by the following general formula (1) having a weight average molecular weight in the range of 500 to 5,000,
The color filter characterized by not containing the dipentaerythritol hexaacrylate modified material represented by following General formula (2) .

(In the formula (1), R ¹ , R ² , and R ³ each represent a group represented by the following general formula (1-1) having an OH group or a carboxyl group at the end, and R ¹ , R ² And at least one of R ³ is a group represented by the following general formula (1-1), n is an integer of 1 or more.)

(In formula (1-1), R ⁴ is a group represented by C ₆ H _4. )

(In the formula (2), R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , and R ¹⁰ are
(CH ₂ ) _β O, (C ₅ H ₁₀ COO) _β
Any one of the groups represented by Β is an integer in the range of 0-5. ) The color filter according to claim 1, wherein the liquid crystal alignment control protrusion is formed of a negative resin composition. The color filter according to claim 1 or 2 , wherein an absolute value of a residual DC of the liquid crystal alignment control protrusion is 500 mV or less.

Images