JP2768120B2 - Photocurable acrylic coloring composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display (L).
The present invention relates to a photocurable acrylic coloring composition applied when forming a black matrix of a color filter in CD) and the like, and in particular, is subjected to a cleaning treatment with isopropyl alcohol in place of a conventional fluorocarbon cleaning agent which has a bad influence on the global environment. The present invention relates to an improvement in a photo-curable acrylic colored composition that can form a uniform color pattern without deteriorating the adhesion to a glass substrate.

[0002]

2. Description of the Related Art A color filter in the above-mentioned LCD and the like is usually provided with a B (blue), G
(Green) and R (red) are provided with transparent color display cell (pixel) patterns (a large number of fine rectangular patterns regularly arranged in the vertical and horizontal directions of the glass substrate), each of which is colored in the three primary colors of light. And, in order to enhance the contrast between the adjacent pixel patterns and improve the reproducibility of color display, a black matrix pattern of a black photocurable acrylic coloring composition along a boundary portion of the adjacent pixel patterns And a transparent overcoat layer is provided on the surface on which the black matrix pattern is formed.

The photocurable acrylic coloring composition constituting the black matrix pattern is generally composed of a coloring pigment, an acrylic monomer, and a pigment dispersant for uniformly dispersing the coloring pigment in a fine particle state in the acrylic monomer. The main components are a photopolymerization initiator for starting the polymerization reaction of the acrylic monomer by light irradiation, a diluting solvent, and an adhesion improver for improving the adhesion to the glass substrate.

In order to form a black matrix pattern using the photocurable acrylic coloring composition, first, the photocurable acrylic coloring composition is uniformly applied on a glass substrate. The exposed photocurable acrylic coloring composition is subjected to a pattern exposure treatment in the form of a black matrix, the polymerization reaction of the acrylic monomer is cured in a pattern shape, and the unexposed portion is developed by a suitable solvent to develop a pattern. After the removal, heat treatment is performed to completely cure the acrylic monomer to form a black matrix pattern.

[0005] The glass substrate on which the black matrix pattern has been formed is subjected to alkali cleaning and acid cleaning, and then, to prevent drying unevenness and increase the adhesion to the overcoat layer. And then sent to the next overcoat layer forming step.

The above-mentioned adhesion improver contained in the photocurable acrylic coloring composition increases the adhesion between the reaction-cured composition and the glass substrate to improve the resistance to Freon washing. Conventionally, pentaerythritol triacrylate, tetraethylene glycol diacrylate, and the like have been used.

[0007]

By the way, there has been a problem that the chlorofluorocarbon detergent conventionally applied to the cleaning treatment has a bad influence on the global environment such as destruction of the earth's ozone layer. Attention has been focused on a method of applying isopropyl alcohol (IPA) as a cleaning agent instead of.

That is, in the cleaning method using IPA, the glass substrate on which the black matrix pattern is formed is first washed with city water, washed with pure water, and further washed with an IPA solution at room temperature. This is a method of performing a cleaning treatment with IPA vapor under a high temperature condition (70 ° C. to 90 ° C.) in order to prevent drying unevenness.

However, although the conventional photocurable acrylic coloring composition has resistance to Freon detergents, it has low resistance to IPA vapor even after reactive curing, so that
There was a problem that the adhesion with the glass substrate was easily reduced by the cleaning treatment with the PA vapor, and dripping-like stains easily appeared on the surface.

The present invention has been made in view of such a problem, and an object thereof is to reduce the adhesion to a glass substrate even if a cleaning treatment using high-temperature IPA vapor is performed instead of the CFC cleaning. It is an object of the present invention to provide a photo-curable acrylic coloring composition which can form a uniform color pattern without any stains or the like.

[0011]

That is, the invention according to claim 1 comprises a color pigment, an acrylic monomer, a pigment dispersant for uniformly dispersing the color pigment in fine particles in the acrylic monomer, and an acrylic monomer by light irradiation. The main component is a photopolymerization initiator for initiating the polymerization reaction, a diluting solvent, and an adhesion improver for improving the adhesion to a glass substrate.
Isopropyl alcohol during the manufacturing process.
Made of color filters that include a cleaning process as a cleaning agent
The method is characterized in that the adhesiveness improving agent is methoxymethylmelamine on the premise of a photocurable acrylic coloring composition for manufacturing .

In such technical means, the methoxymethylmelamine acts to crosslink an acrylic polymer produced by a polymerization reaction of an acrylic monomer to improve the resistance to IPA vapor and to increase the adhesion to a glass substrate. This makes it possible to form a uniform colored pattern without stains firmly adhered to the glass substrate during the cleaning treatment with IPA vapor.

The acrylic monomers are polymerized with each other by light irradiation or heat treatment before and after the irradiation to form an acrylic polymer and have the function of uniformly holding the color pigment in a fine particle state. For example, butyl methacrylate And a mixture of one or more monomers selected from acrylic monomers such as acrylic acid, methacrylic acid, hydroxyethyl acrylate, methyl methacrylate, benzyl methacrylate, and dimethylaminoethyl methacrylate. In particular, when the acrylic monomer has two or three functional groups having an unsaturated bond, the polymer formed by polymerization of the acrylic monomer has a three-dimensional structure. Therefore, the resistance to the IPA vapor is further improved.

The invention according to claim 2 has been made based on such technical background, and based on the photocurable acrylic coloring composition according to claim 1, the acrylic monomer is represented by the following chemical formula (1). It has two or three functional groups shown.

[0015]

Embedded image (Wherein R represents a hydrogen atom or a methyl group) In the invention according to claim 2, the acrylic monomer having two or three functional groups represented by the chemical formula (1) is an acrylic monomer formed by polymerization thereof. Since the polymer has a three-dimensional structure, the resistance to the IPA vapor is further improved.

As the acrylic monomer, for example, trimethylolpropane triacrylate represented by the following chemical formula (2) can be used.

[0017]

Embedded image Other examples of the acrylic monomer having two or three functional groups represented by the chemical formula (1) include a trimethylolpropane PO-modified (n) represented by the following chemical formula (3).
= 1) triacrylate, trimethylolpropane PO-modified (n = 2) triacrylate represented by the following chemical formula (4), and tris (acryloyloxyethyl) isocyanurate represented by the following chemical formula (5).

[0018]

Embedded image

Embedded image

Embedded image Further, a modified product obtained by modifying the above tris (acryloyloxyethyl) isocyanurate with ε-caprolactone as an acrylic monomer having two or three functional groups represented by the above chemical formula (1) is applied. May be.

Next, in the inventions according to the first and second aspects of the present invention, pigments such as white, blue, green, red, and black can be used as the color pigment, and they form a black stripe pattern of a color filter in an LCD. In this case, a single black pigment such as carbon black alone or a mixed black pigment which mixes blue, green and red pigments to give a black color as a whole may be applied.

Examples of the pigment dispersant which uniformly disperses the color pigment in the acrylic monomer in a fine particle state and forms a uniform color pattern after the curing reaction include, for example, sodium naphthalenebenzenesulfonate. And a surfactant such as polyoxyethylene nonyl phenyl ether.

In the invention according to claims 1 and 2, the photopolymerization initiator for initiating the polymerization reaction of the acrylic monomer by light irradiation includes, for example, the following chemical formula (6):
Benzophenone represented by the following formula (7), 4,4′-dichlorobenzophenone represented by the following chemical formula (8), 2,4-diethylthioxanthone represented by the following chemical formula (8), and 2,2-dimethoxy- represented by the following chemical formula (9) 2-Phenylacetophenone, 3,3'-dichloro-4-methoxybenzophenone represented by the following chemical formula (10) and the like can be applied, and as a diluting solvent, cyclohexanone and the like can be applied.

[0022]

Embedded image

Embedded image

Embedded image

Embedded image

Embedded image Next, regarding the photocurable acrylic coloring composition according to claims 1 and 2, 3.0 to 10.0% by weight of a coloring pigment, 5.0 to 10.0% by weight of an acrylic monomer, and 0 of a pigment dispersant. 0.5 to 1.0% by weight, a photopolymerization initiator 1.0 to 5.0% by weight, a diluting solvent 80.0 to 90.0% by weight, and an adhesion improver 0.1 to methoxymethylmelamine 0.1 to 1.0%. 5.
It can be manufactured by mixing 0% by weight. The photocurable acrylic coloring composition has the above chemical formula (1)
It is desirable that the composition contains an acrylic monomer having two or three functional groups represented by the following formula: 0.2 to 5.0% by weight of the whole composition.

The following composition examples are given below showing specific mixing ratios of the photocurable acrylic coloring composition.

Color pigment 5.8 wt% Acrylic monomer Butyl methacrylate 3.5 wt% Methacrylic acid 1.3 wt% Hydroxyethyl methacrylate 1.0 wt% Methyl methacrylate 0.6 wt% Dimethylaminoethyl methacrylate 0.6 wt% Trimethylolpropane PO modified (N = 1) triacrylate 3.2 wt% pigment dispersant sodium naphthalenebenzenesulfonate 0.6 wt% photopolymerization initiator 2,2-dimethoxy-2-phenylacetophenone 1.3 wt% diluent solvent cyclohexanone 81.7 wt% The photocurable acrylic coloring composition according to claim 1 or 2 can be used to form a black matrix pattern of a color filter in an LCD.
It can be used to form the color display cell (pixel). In any case, the photocurable acrylic coloring composition is uniformly applied on a predetermined glass substrate, and the applied photocurable acrylic coloring composition is subjected to a pattern exposure treatment of a predetermined shape. The acrylic monomers are polymerized and cured in a pattern,
The black matrix pattern or the pixel can be formed by removing the unexposed portions by appropriately developing with a solvent and then heating (post-baking) to completely cure the acrylic monomer.
The post-baking may be performed at a temperature of 180 ° C. or more. However, in order to improve the resistance to IPA vapor and increase the adhesion to the glass substrate, 200 to 22 ° C.
It is desirable to carry out at a temperature of 0 ° C. This is because adhesion strength tends to be relatively small when post-baking at a temperature lower than 200 ° C. or when post-baking at a temperature exceeding 220 ° C.

Next, the glass substrate on which the above-mentioned black matrix pattern or pixels are formed is firstly washed with city water and then with pure water according to a standard method, and further washed with an IPA solution at room temperature to obtain a drying unevenness. After performing a cleaning treatment with IPA vapor under a high temperature condition [70 ° C. to 90 ° C.] in order to prevent the above, the substrate is sent to the next step.

[0026]

According to the first aspect of the present invention, since the adhesion improver which forms a part of the photocurable acrylic coloring composition and improves the adhesion to the glass substrate is composed of methoxymethylmelamine, Melamine crosslinks the acrylic polymer generated by the polymerization reaction of the acrylic monomer to improve the resistance to IPA vapor and also increases the adhesion to the glass substrate.

According to the second aspect of the present invention, the acrylic monomer constituting a part of the photocurable acrylic coloring composition has a functional group represented by the chemical formula (1) of 2 or
Since there are three, the acrylic polymer produced by the polymerization reaction has a three-dimensional structure, which further improves the resistance to the IPA vapor and further increases the adhesion to the glass substrate.

[0028]

Embodiments of the present invention will be described below in detail.

Example 1 A photocurable acrylic coloring composition having the following composition was used.

(Photocurable Colored Acrylic Composition) Colored Pigment Carbon Black 5.77 wt% Acrylic monomer Butyl methacrylate 3.52 wt% Methacrylic acid 1.28 wt% Hydroxyethyl methacrylate 0.96 wt% Methyl methacrylate 0.64 wt% Dimethyl Aminoethyl methacrylate 0.62 wt% Trimethylolpropane PO-modified (n = 1) triacrylate 3.20 wt% Pigment dispersant Sodium naphthalenebenzenesulfonate 0.64 wt% Photopolymerization initiator 2,2-dimethoxy-2-phenylacetophenone 1 .25 wt% Diluent solvent Cyclohexanone 81.33 wt% Adhesion improver methoxymethyl melamine 0.79 wt% This photocurable acrylic coloring composition was applied onto a glass substrate by spin coating at a rotational speed of 500 rpm for 2 seconds. First was coated with matter, followed after a uniform film surface is rotated again at a rotational speed 750 rpm and 5 seconds, 70
It dried at 20 degreeC and 20 minutes.

Next, a polyvinyl alcohol (P) is applied on the photocurable acrylic colored composition coating film to prevent oxidation.
VA) A PVA solution obtained by diluting the stock solution with water is applied by a spin coating method at a rotational speed of 500 rpm for 2 seconds, and then rotated again at a rotational speed of 1000 rpm for 10 seconds to uniform the film surface. After that, a drying treatment was performed.

Then, a photomask of a predetermined pattern is superposed on the photocurable colored acrylic composition coating film coated with the PVA solution at intervals of 5 μm, and irradiated with ultraviolet rays at an exposure amount of 100 mJ / cm ^2. After the development, a heat treatment (post-baking) was performed. The exposure pattern is a mesh pattern having 30 μm-wide lines at 1 mm intervals.
0 ° C, 190 ° C, 200 ° C, 210 ° C, 220 ° C, 23
The test was performed for 2 hours under each temperature condition of 0 ° C. and 240 ° C.

The glass substrate on which the mesh pattern was formed was examined under the green light with the naked eye and a microscope to check for stains. As a result, no stain was observed on any of the glass substrates and uniform color was observed. It was confirmed that it had a mesh-shaped pattern.

Next, the glass substrate having the mesh pattern formed thereon is firstly washed with an alkali and an acid, washed with city water and pure water, and then placed in an IPA solution at room temperature. Immersion for 30 minutes for 30 minutes
Washing was performed for 2 minutes with IPA vapor at a high temperature of 3 ° C.

Then, 30 on the obtained grid pattern is obtained.
A cellophane tape was stuck on an area of 30 mm × 30 mm (including the 30 vertical and 30 horizontal lines), and the cellophane tape was peeled off. The number of cells peeled off with the peeling of the cellophane tape was counted. (Cross cut method). Table 1 shows the results.

Example 2 Substantially the same as Example 1 except that trimethylolpropane PO-modified (n = 2) triacrylate was used in place of the above trimethylolpropane PO-modified (n = 1) triacrylate. It is.

Then, as in Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, no stain was observed on the glass substrate that had been post-baked at any temperature. It had a colored grid pattern.

Table 1 shows the results obtained by the cross-cut method.

Example 3 This example is substantially the same as Example 1 except that tris (acryloyloxyethyl) isocyanurate was used in place of the trimethylolpropane PO-modified (n = 1) triacrylate.

Then, as in Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, no stain was observed on the glass substrate post-baked at any temperature. It had a colored grid pattern.

Table 1 shows the results obtained by the cross-cut method.

Example 4 ε-tris (acryloyloxyethyl) isocyanurate was used instead of the trimethylolpropane PO-modified (n = 1) triacrylate.
It is almost the same as Example 1 except that the modified caprolactam is applied.

Then, as in Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, no stain was observed on the glass substrate post-baked at any temperature. It had a colored grid pattern.

Table 1 shows the results obtained by the cross-cut method.

Comparative Example 1 The photocurable acrylic coloring composition was substantially the same as Example 1 except that the photocurable acrylic coloring composition having the following composition was applied.

(Photo-curable Colored Acrylic Composition) Colored Pigment Carbon Black 5.81 wt% Acrylic monomer 3.55 wt% Methacrylic acid 1.29 wt% Hydroxyethyl methacrylate 0.97 wt% Methyl methacrylate 0.65 wt% Dimethyl Aminoethyl methacrylate 0.63 wt% Pigment dispersant Sodium naphthalenebenzenesulfonate 0.65 wt% Photopolymerization initiator 2,2-dimethoxy-2-phenylacetophenone 1.26 wt% Diluent solvent Cyclohexanone 81.96 wt% Adhesion improver tetraethylene Glycol diacrylate 3.23 wt% Then, as in Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. Is shaped stain was confirmed.

Table 1 shows the results obtained by the cross-cut method.

[Comparative Example 2] This is substantially the same as Comparative Example 1 except that polyethylene glycol diacrylate is used in place of the above tetraethylene glycol diacrylate.

Then, as in Comparative Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, dripping spots were observed on the glass substrate post-baked at any temperature. .

Table 1 shows the results obtained by the cross-cut method.

Comparative Example 3 Trimethylolpropane PO was used in place of the above tetraethylene glycol diacrylate.
It is substantially the same as Comparative Example 1 except that a modified (n = 1) triacrylate is applied.

Then, as in Comparative Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, dripping spots were observed on the glass substrate post-baked at any temperature. .

Table 1 shows the results obtained by the cross-cut method.

Comparative Example 4 Trimethylolpropane PO was used in place of the above tetraethylene glycol diacrylate.
It is substantially the same as Comparative Example 1 except that a modified (n = 2) triacrylate is applied.

Then, as in Comparative Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, dripping spots were observed on the glass substrate post-baked at any temperature. .

Table 1 shows the results obtained by the cross-cut method.

Comparative Example 5 The procedure was substantially the same as that of Comparative Example 1 except that isocyanuric acid EO-modified (n = 3) triacrylate was used in place of the above tetraethylene glycol diacrylate.

Then, as in Comparative Example 1, the glass substrate on which the grid pattern was formed was observed with the naked eye and under a microscope. As a result, dripping spots were observed on the glass substrate post-baked at any temperature. .

Table 1 shows the results obtained by the cross-cut method.

Comparative Example 6 The procedure was substantially the same as that of Comparative Example 1 except that isocyanuric acid EO-modified (n = 3) .ε-caprolactone-modified triacrylate was used in place of the above tetraethylene glycol diacrylate. .

Then, as in Comparative Example 1, the glass substrate on which the mesh pattern was formed was observed with the naked eye and under a microscope. As a result, dripping spots were observed on the glass substrate post-baked at any temperature. .

Table 1 shows the results obtained by the cross-cut method.

[0063]

[Table 1] [Confirmation] As is clear from the results in Table 1, each of the comparative examples to which the photocurable acrylic coloring composition containing no methoxymethylmelamine was applied had weak adhesion between the glass substrate and the mesh pattern. In each of the examples in which the photocurable acrylic coloring composition containing methoxymethylmelamine is applied, the adhesion between the glass substrate and the grid pattern is strong, whereas the cross-cut method peels a lot. It was confirmed that the film was hardly peeled off by the method. Above all, it can be seen that the post-baked at a temperature of 200 to 220 ° C. has particularly excellent adhesion.

From the results of observation with the naked eye and a microscope, a dripping spot was observed in the case of the comparative example, while no such spot was observed in the case of the embodiment, and a uniform colored pattern was obtained. Could be formed.

[0065]

According to the first and second aspects of the present invention, methoxymethyl melamine constituting the adhesion improver crosslinks an acrylic polymer produced by a polymerization reaction of an acrylic monomer to improve resistance to IPA vapor. It also improves the adhesion to the glass substrate.

Therefore, even if a cleaning treatment using high-temperature IPA vapor is performed instead of the chlorofluorocarbon cleaning, the adhesion to the glass substrate is not reduced, and an effect of forming a uniform color pattern without stains is obtained. .

Continuation of front page (56) References JP-A-60-237437 (JP, A) JP-A-1-77027 (JP, A) JP-A-61-236553 (JP, A) JP-A-4-106546 (JP) , A) (58) Field surveyed (Int.Cl. ⁶ , DB name) G03F 7/027 G02B 5/20 101 G03F 7/004 G03F 7/085

Claims (2)

(57) [Claims] 1. A color pigment, an acrylic monomer, a pigment dispersant for uniformly dispersing the color pigment in a fine particle state in the acrylic monomer, a photopolymerization initiator for initiating a polymerization reaction of the acrylic monomer by light irradiation, and a diluting solvent. And an adhesiveness improving agent for improving the adhesiveness to a glass substrate as a main component , and isopropyl alcohol is used during the manufacturing process.
Color filter that includes a cleaning process using
-A photocurable acrylic colored composition for producing a color filter , wherein the adhesion improver is methoxymethylmelamine. 2. The photocurable acrylic coloring for producing a color filter according to claim 1, wherein the acrylic monomer has two or three functional groups represented by the following chemical formula (1). Composition. Embedded image (Where R represents a hydrogen atom or a methyl group)