KR20080107298A - Photosensitive resin composition for black resist, and light shielding film and color filter formed by using the same - Google Patents

Abstract

A photosensitive resin composition for a black resist, a light screening film formed byusing the composition, and a color filter for a ink-jet process color filter containing the light screening film are provided to improve pattern size dimensional stability in case of a thick film of 1.5 micrometers or more and to enhance development margin, pattern adhesion and clearness of pattern edge shape. A photosensitive resin composition for a black resist comprises a radiation curing resin and/or a radiation curing monomer; at least one light screening pigment selected from a black organic pigment, a mixed color organic pigment and a light screening material; and a granular silica, wherein the primary particle size of the granular silica has an average of 10-50 nm, the ratio of the average of the primary particle size of the granular silica/that of the light screening pigment is 0.2-5.0; and the ratio of the weight of the granular silica/that of the light screening pigment is 0.1-1.0.

Description

PHOTOSENSITIVE RESIN COMPOSITION FOR BLACK RESIST, AND LIGHT SHIELDING FILM AND COLOR FILTER FORMED BY USING THE SAME}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a photosensitive resin composition for a black resist of a photosensitive alkaline aqueous solution development type, and a light shielding film formed by using the same, and a color filter, and in particular, a photosensitive resin composition for black resist suitable for forming a fine light shielding film on a transparent substrate, and a light shielding film , And color filters.

A color filter generally forms a black mattress on the surface of a transparent substrate such as glass or plastic sheet, and then three or more different colors such as red, green, and blue are sequentially formed in a color pattern such as a stripe shape or a mosaic shape. Let's do it. The pattern size varies depending on the color filter application and each color, but is about 5 to 700 µm. Moreover, the position accuracy which overlaps each other is several micrometers-several tens micrometers, and is manufactured by the microfabrication technique with high dimensional precision.

Typical manufacturing methods of color filters include dyeing, printing, pigment dispersion, electrodeposition, and the like. Among these, in particular, a pigment dispersion method of forming a color filter image by applying a photopolymerizable composition containing a color material on a transparent substrate and repeating image exposure, development, and curing as necessary, is a method of dispersing a color filter pixel. The film has been widely adopted because of its high degree of film thickness, excellent durability in light resistance, heat resistance, and the like and small defects such as pinholes.

Black mattresses are generally arranged in a lattice, stripe, or mosaic form between red, green, and blue color patterns, and play a role in preventing the malfunction of TFTs due to the improvement of contrast due to the mixed color control of each color or the leakage of light. . For this reason, high light-shielding property is calculated | required by a black mattress. Conventionally, the method of forming a black mattress with metal films, such as chromium, was common. Since this method deposits a metal, such as chromium, on a transparent substrate and etches a chromium layer through a photolithography process, high light-shielding property is obtained at a thin film thickness with high precision. On the other hand, it has a long manufacturing process and a low productivity method, and includes problems such as high cost and environmental problems caused by the waste liquid of the etching process.

Therefore, as a solution to these problems, Patent Literature 1 proposes a photolithography method containing a photosensitive resin. However, in order to express the light shielding property (optical density) equivalent to the black mattress by metal films, such as chromium, also about the resin light shielding film obtained by this method, it is necessary to increase content of a light-shielding pigment etc. When the light shielding ability is required in the entire wavelength region, since the light-shielding pigment absorbs the ultraviolet ray in the process of irradiating ultraviolet rays and photocuring, 1) the difference in the crosslinking density with respect to the film thickness direction also occurs in the exposed portion, 2) It is difficult to make a difference in crosslinking density in the exposed part and the unexposed part, even if the surface is sufficiently photocured, and 3) a large amount of light-shielding pigments insoluble in the developer. Since it mixes, the photosensitive sensitivity, resolution, adhesiveness, developability, and edge shape of the black resist are remarkable. There are challenges in terms of sharpness, etc., have been higher than the light shielding is required, or the development of a clear black mattress edge shape conforming to the pattern.

In order to achieve high brightness, high saturation, and high resolution, resin black mattresses, which are one of the color filter related materials, have been mainly used in thin films having a thickness of about 1 μm, but higher light shielding is required than in the past. Resin black mattresses having a thickness of more than 1.5 mu m are also newly introduced.

In addition, recently, a panel adopting a color filter on array technology has attracted attention. This technology integrates a color filter substrate and a TFT array substrate, which eliminates the need for precise positioning of the two substrates, and makes it possible to refine the red, blue, and green pixels of the color filter to the limit. Related. Since the resin black mattress for color filter-on-array needs high light-shielding property, film thickness of 2 micrometers or more is calculated | required.

However, as the film thickness of the resin black mattress increases, the difference in crosslinking density with respect to the film thickness direction in the exposed portion increases, so that it becomes more difficult to achieve high sensitivity and obtain a black pattern having a good shape. Further, in the subsequent heat firing process, since there is a difference in the crosslinking density with respect to the film thickness direction in the exposed portion, a difference occurs in the thermal curing shrinkage between the surface of the coating film and the substrate and the surface roughness of the coating film is increased, resulting in surface smoothness. This deteriorates and wrinkles occur on the surface, which adversely affects the formation of subsequent pixels of red, blue, and green. It is possible to prevent an increase in the surface roughness by changing the exposure conditions or the heat firing conditions, but it is not preferable because the patterning characteristics and the reliability characteristics are likely to be impaired.

In Patent Literature 2, a black resist containing an unsaturated group-containing compound obtained by further reacting a reaction product of a specific aromatic epoxy compound with (meth) acrylic acid with polybasic carboxylic acid or an anhydride thereof as a resin main component has a high light shielding ratio, It is reported that it is easy to form a fine pattern, and besides, it becomes a light-shielding thin film formation composition which is excellent also in reversing property, heat resistance, adhesiveness, and room temperature storage stability. However, Patent Document 2 also describes a black resist for thin films near 1 μm, which is a standard film thickness of a black mattress, and does not mention photocurability and development characteristics related to a film thickness exceeding 1.5 μm.

Examples of the color filter related material characterized by being a thick film are shown in Patent Documents 3 to 5 and the like. However, Patent Document 3 not only relates to the color filter forming method in the printing method without the exposure and the thermosetting process, but also to the method of forming the color mattresses such as red, blue, green, etc. instead of the resin black mattress. Patent document 4 is a method of forming a thick film along the backlight, but this is also not black, and since blue is used as the light shielding film, it is not sufficient in terms of light shielding properties, and because it performs back exposure different from a general process, The challenge remains in terms of yield. Patent document 5 is a content regarding the protective film for color filters.

As one of methods to prevent surface roughness increase after thermal firing, it is generally effective to increase the molecular weight of the binder resin frequently by reducing the thermal curing shrinkage of the black resist, but deterioration and peeling of the photocurability and development characteristics occur. In the complementary relationship, a good pattern shape with a sufficiently wide development margin and no increase in surface roughness of the coating film are complied with, and it is particularly difficult to achieve compatibility with the thick film resin black mattress. In the resin black mattress obtained by the above, reports on the photosensitive resin composition for black resist which is a thick film whose resin black mattress thick film exceeds 1.5 micrometers and the light shielding film formed using this are not seen in the past.

In addition, the use of a large amount of light shielding material as a means of high light shielding has been tested, but when a conductive material such as carbon is used as the light shielding material, there is a problem that the volume resistance of the black mattress is lowered and the reliability of the display device is lowered. have.

[Patent Document 1] Japanese Patent Application Laid-Open No. 4-177202

[Patent Document 2] Japanese Patent Application Laid-Open No. 8-278629

[Patent Document 3] Japanese Patent Application Laid-Open No. 5-045513

[Patent Document 4] Japanese Patent Application Laid-Open No. 5-181000

[Patent Document 5] Japanese Patent Application Laid-Open No. 5-288926

Accordingly, it is an object of the present invention to solve the above problem and to form a pattern excellent in pattern dimensional stability and good in definition margin, pattern adhesion, and edge shape sharpness of a pattern even in the case of a thick film exceeding 1.5 µm. In addition, even in the subsequent heating step, the coating surface is smooth and surface deterioration due to thermal curing shrinkage does not occur, and there is no decrease in volume resistance even when a conductive material such as carbon is used as the light shielding material. It is to provide a photosensitive resin composition for resist. Further, another object of the present invention is to provide a light shielding film and a color filter formed using the photosensitive resin composition for black resist.

That is, the present invention comprises (a) a photocurable resin and / or a photocurable monomer, (b) at least one light-shielding pigment selected from black organic pigments, mixed organic pigments and light-shielding materials, and (c) granular silica. In the photosensitive resin composition for black resists, the average value of the primary particle diameter of the granular silica of (a) component is 10-50 nm, and of the average value of the primary particle diameter of a light-shielding pigment (b) and granular silica (c). The ratio ((C) / (B)) is in the range of 0.2 to 5.0, and the weight ratio ((C) / (B)) of the granular silica (C) to the light-shielding pigment (B) in the composition is 0.1 to 1.0. It is a range, The photosensitive resin composition for black resists characterized by the above-mentioned.

In addition, the present invention is applied to the photosensitive resin composition for black resist on a transparent substrate and dried, and then the steps of (a) exposure by an ultraviolet exposure apparatus, (b) development by aqueous alkali solution, and (c) heat treatment As a light shielding film obtained as an essential part, it is a light shielding film characterized by the taper angle being 60 degrees or more.

Moreover, this invention is a color filter for inkjet process color filters in which the light shielding partition as a black mattress is comprised with the said light shielding film, and whose film thickness is 1.5-4 micrometers.

The photosensitive resin composition for black resists of the present invention is excellent in pattern dimensional stability even when a thick film black mattress having a thickness of more than 1.5 µm is obtained, and also has a development margin, pattern adhesion, and sharpness of the edge shape of the pattern. It is possible to form a good pattern. Further, in the subsequent heat firing step, the surface of the coating film is smooth, the surface roughness due to thermal curing shrinkage does not occur, and even if a conductive material such as carbon is used as the light shielding material, the reduction in volume resistance is reduced as much as possible. can do.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail. The composition of this invention contains (A)-(C) component as an essential component. Here, it is preferable that the photocurable resin which is (a) component is the following unsaturated group containing compound, for example. That is, polybasic acid carboxylic acid or its anhydride to a compound having a hydroxy group obtained by reacting (meth) acrylic acid (which means "acrylic acid and / or methacrylic acid") with an epoxy compound having two glycidyl ether groups derived from bisphenols. It is an epoxy (meth) acrylate acid adduct obtained by making it react. Here, the epoxy compound derived from bisphenols means an epoxy compound obtained by reacting bisphenols with epihalohydrin. The related epoxy compound and the unsaturated group containing compound (epoxy (meth) acrylate acid adduct) derived from the said epoxy compound are known by the said patent document 2, etc., and can use a related compound widely.

In the above case, since the photocurable resin (A) has both ethylenically unsaturated double bonds and carboxyl groups, the photosensitive resin composition for black resist is provided with excellent photocurability, good developability, patterning properties, and the like to improve physical properties of the light shielding film. Cause. That is, the photocurable resin which is (a) component, is preferably derived from the epoxy compound represented by following General formula (1). This epoxy compound is derived from bisphenols. Therefore, since a unsaturated group containing compound is understood by demonstrating bisphenols, a preferable specific example is demonstrated by bisphenols.

Wherein R ₁ and R ₂ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a phenyl group or a halogen atom, and X is -CO-, -SO _2- , -C (CF ₃ ) ₂ -, -Si (CH ₃ ) _2- , -CH _2- , -C (CH ₃ ) _2- , -O-, 9, 9-fluorenyl group represented by the following formula

Or absent, n is an integer of 0 to 10)

As bisphenols which provide a preferable unsaturated group containing compound, the following are mentioned. Bis (4-hydroxyphenyl) ketone, bis (4-hydroxy-3,5-dimethylphenyl) ketone, bis (4-hydroxy-3,5-dichlorophenyl) ketone, bis (4-hydroxyphenyl) Sulfone, bis (4-hydroxy-3,5-dimethylphenyl) sulfone, bis (4-hydroxy-3,5-dichlorophenyl) sulfone, bis (4-hydroxyphenyl) hexafluoropropane, bis (4 -Hydroxy-3,5-dimethylphenyl) hexafluoropropane, bis (4-hydroxy-3,5-dichlorophenyl) hexafluoropropane, bis (4-hydroxyphenyl) dimethylsilane, bis (4- Hydroxy-3,5-dimethylphenyl) dimethylsilane, bis (4-hydroxy-3,5-dichlorophenyl) dimethylsilane, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5 -Dichlorophenyl) methane, bis (4-hydroxy-3,5-dibromophenyl) methane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3 , 5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxy-3-chlorophenyl) propane, bis (4-hydroxyphenyl) ether, bis (4-hydroxy-3,5-dimethylphenyl) ether, bis (4-hydroxy 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-, a compound containing -3,5-dichlorophenyl) ether, etc., wherein X is said 9,9-fluorenyl group. Hydroxy-3-methylphenyl) fluorene, 9,9-bis (4-hydroxy-3-chlorophenyl) fluorene, 9,9-bis (4-hydroxy-3-bromophenyl) fluorene, 9 , 9-bis (4-hydroxy-3-fluorophenyl) fluorene, 9,9-bis (4-hydroxy-3-methoxyphenyl) fluorene, 9,9-bis (4-hydroxy- 3,5-dimethylphenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dichlorophenyl) fluorene, 9,9-bis (4-hydroxy-3,5-dibromo Phenyl) fluorene and the like, and compounds such as 4,4'-biphenol and 3,3'-biphenol.

The photocurable resin as the component (A) can be obtained from the above-described epoxy compounds derived from bisphenols, but in addition to the related epoxy compounds, phenol novolak type epoxy compounds and cresol novolak type epoxy compounds also have two glycidyl ether groups. Any compound containing a compound can be used. When the bisphenols are glycidyl etherized, oligomer units are mixed, but if the average value of n in the formula (1) is in the range of 0 to 10, preferably 0 to 2, there is a problem in the performance of the present resin composition. none.

Moreover, as polybasic acid carboxylic acid or its acid anhydride obtained by reaction with the hydroxyl group in the epoxy (meth) acrylate molecule obtained by making such an epoxy compound and (meth) acrylic acid react, for example, maleic acid, succinic acid, itaconic acid, phthalic acid, Tetrahydrophthalic acid, hexahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, chloric acid, methyltetrahydrophthalic acid, trimellitic acid, pyromellitic acid and the like, or an acid anhydride thereof, and also benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, biphenyl Aromatic polyhydric carboxylic acid, such as ether tetracarboxylic acid, its acid dianhydride, etc. are mentioned. The use ratio of acid anhydride and acid dianhydride can be selected to a ratio suitable for forming a fine pattern in accordance with exposure and alkali development operations.

About photocurable resin of (A) component, it is also possible to use only 1 type, and can use 2 or more types of mixtures. In addition, although reaction of an epoxy compound and (meth) acrylic acid and reaction of the epoxy (meth) acrylate obtained by this reaction with a polybasic acid or its acid anhydride can employ | adopt the method well-known in the said patent document 2, etc., Especially It is not limited.

In addition, in this invention, since (a) component hardens | cures (polymerizes) with light, it includes the case where the photosensitive resin composition contains only the component (monomer) which is not resinized in the uncured state. That is, as a photocurable monomer used as (a) component, it is a photopolymerizable monomer which has at least 1 or more ethylenically unsaturated bond, For example, 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) ) Monomers having hydroxyl groups such as acrylate and 2-ethylhexyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, Tetraethylene glycol di (meth) acrylate, tetramethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylol ethane tri (meth) acrylate, pentaerythritol di (meth) acrylate, Pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hex (Meth) acrylic acid esters, such as a (meth) acrylate and a glycerol (meth) acrylate, can be enumerated, These compounds can be used individually by 1 type, It is also possible to use 2 or more types together. Do.

Although the photosensitive resin composition for black resists of this invention contains the photopolymerizable compound of (A) component, it is preferable to contain a photoinitiator in order to photocure this. The photopolymerization initiator generates radical species by ultraviolet light irradiation, initiates radical polymerization in addition to the photopolymerizable compound to cure the resin composition.

Examples of the photopolymerization initiator include benzophenone, Michler's ketone, N, N'-tetramethyl-4,4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, and 4,4'-diethylaminobenzo Aromatic ketones such as phenone, 2-ethylanthraquinone and phenanthrene, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, benzoin such as methyl benzoin and ethyl benzoin, 2- (ο-chlorophenyl) -4,5-phenylimidazole dimer, 2- (ο-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (ο-fluor Rophenyl) -4,5-diphenylimidazole dimer, 2- (ο-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4,5-triarylimidazole 2 2-mer, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloro Methyl-5- (p-cyanostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (p-methoxystyryl) -1,3,4-oxadiazole, and the like Halomethylthiazole Compound, 2,4,6-tris (trichloromethyl) -1,3,5-triadine, 2-methyl-4,6-bis (trichloromethyl) -1,3,5-triadine, 2- Phenyl-4,6-bis (trichloromethyl) -1,3,5-triadine, 2- (4-chlorophenyl) -4,6-bis (trichloromethyl) -1,3,5-triadine , 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triadine, 2- (4-methoxynaphthyl) -4,6-bis (trichloro Rmethyl) -1,3,5-triadine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triadine, 2- (3,4 , 5-trimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triadine, 2- (4-methylthiostyryl) -4,6-bis (trichloromethyl Halomethyl-S-triadine compounds such as) -1,3,5-triadine, 2,2-dimethoxy-1,2-diphenylethan-1-one and 2-methyl-1- [4- ( Methylthio) phenyl] -2-morpholinopropanoone, 2-benzyl-2-dimethylamino-1- [4-morpholinophenyl] -butanone-1,1-hydroxy-cyclohexyl-phenyl ketone, etc. Photoinitiator, Japanese patent application The oxime ester-based initiators such as those disclosed in No. 2004-534794 are exemplified.

These photoinitiators can be used individually or in mixture of 2 or more types. Moreover, although it does not act as a photoinitiator or a sensitizer by itself, it is also possible to add the compound which can increase the capability of a photoinitiator or a sensitizer by using it in combination with the said compound. As such a compound, tertiary amines, such as triethanolamine which are effective when used in combination with benzophenone, can be mentioned, for example.

As for the usage-amount of a photoinitiator, 7-20 weight part is suitable on the basis of a total of 100 weight part of (A) component. When the blending ratio of the photopolymerization initiator is less than 7 parts by weight, the speed of photopolymerization is slowed down, and the sensitivity is lowered. On the other hand, when the content ratio exceeds 20 parts by weight, the sensitivity is too strong, and the pattern line width is increased with respect to the pattern mask. There exists a possibility that the problem that a faithful line width cannot be reproduced with respect to a mask, and a pattern edge is uneven and it does not become clear is made.

As light-shielding pigments, such as black organic pigment, mixed organic pigment, or light-shielding material which are (b) components, what is excellent in heat resistance, light resistance, and solvent resistance is preferable. Here, as black organic pigment, perylene black, cyanine black, etc. are mentioned, for example. Examples of mixed organic pigments include those which are similarly blackened by mixing at least two or more pigments selected from red, blue, green, purple, yellow, cyanine, magenta and the like. Examples of the light shielding material include carbon black, chromium oxide, iron oxide, titanium black, aniline black, and cyanine black, and two or more kinds can be appropriately selected and used. In particular, carbon black has a light shielding property, surface smoothness and dispersion. It is preferable at the point that stability and compatibility with resin are favorable.

About the compounding ratio of (b) component, it is good that it is 50-150 weight part with respect to a total of 100 weight part of said (A) component and a photoinitiator component. If it is less than 50 parts by weight, the light shielding property is not sufficient. If the content exceeds 150 parts by weight, the content of the photosensitive resin serving as the original binder decreases, which leads to an undesirable problem of impairing the developing characteristics and impairing the film forming ability.

The granular silica of component (C) is not limited to the production method or shape (spherical or non-spherical) called gas phase reaction or liquid phase reaction, but is preferably amorphous granular silica synthesized by gas phase method in terms of low cohesiveness and excellent dispersibility. Do. Although the average value of the primary particle diameter of granular silica is suitably selected according to the kind of carbon black, it is necessary to be in the range of 10-50 nm, Preferably it is the range of 15-40 nm. If this ratio does not satisfy 10 nm, the dispersion stability of the silica in the resin composition cannot be sufficiently retained, and if it exceeds 50 nm, the surface roughness of the coating film becomes large and a good color filter cannot be formed.

 The ratio ((C) / (B)) of the average value of the primary particle diameters of the light-shielding pigment (B) and the granular silica (C) should be in the range of 0.2 to 5.0, preferably 0.3 to 4.0. Range. If this ratio does not satisfy 0.2, the dispersion stability of a long term cannot be retained, and if it exceeds 5.0, after coating and drying on a substrate, exposure by an ultraviolet exposure apparatus, development with an aqueous alkali solution, and heat treatment Substrate adhesiveness of the light shielding film obtained through this deteriorates, and the effective pixel formation ability in a photolithography process cannot be exhibited.

In addition, the weight ratio ((C) / (B)) of the granular silica (C) and the light-shielding pigment (B) needs to be in the range of 0.1 to 1.0, and preferably in the range of 0.2 to 0.9. If this ratio does not satisfy 0.1, the volume resistivity is lowered for the light-shielding film obtained through the application of a UV exposure apparatus, development with an aqueous alkali solution, and heat treatment after application and drying on a substrate, and the taper angle is 60 °. It becomes less than, wrinkles become remarkable, surface roughness becomes large, and the effect of this invention cannot fully be exhibited. Moreover, when it exceeds 1.0, in the practical thick film, the light-shielding effect required as a black mattress will not be obtained.

The weight ratio ([(B) + (C)] / (R)) between the total weight of the light-shielding pigment (B) and the granular silica (C) and the weight of the resin solid component (R) in the photosensitive resin composition was 0.4 to 0.4. It is preferably in the range of 2.2. Here, the resin solid content means that the thing which was disperse | distributed as a granular form in resist, such as a pigment and a granular silica component, from the whole solid content (it remains as solid content after hardening) here. When this ratio does not satisfy 0.4, wrinkles become remarkable and the surface roughness becomes large. On the contrary, when it exceeds 2.2, pattern formation becomes difficult in the photolithography process.

In the photosensitive resin composition for black resists of this invention, it is preferable to use a solvent other than the said (A)-(poly) component. As a solvent, For example, alcohols, such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, terpenes, such as (alpha)-or (beta)-terpineol, acetone, methyl ethyl ketone, cyclohexanone, Ketones such as N-methyl-2-pyrrolidone, aromatic hydrocarbons such as toluene, xylene, tetramethylbenzene, cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, Glycol ethers such as butyl carbitol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and ethyl Acetate, butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, ethyl carbitol acetate, Ester acetates, such as butyl carbitol acetate, a propylene glycol monomethyl ether acetate, and a propylene glycol monoethyl ether acetate, etc. are mentioned, It can be set as a uniform solution composition by melt | dissolving and mixing using these.

In addition, additives such as a curing accelerator, a thermal polymerization inhibitor, a plasticizer, a filler, a solvent, a leveling agent, and an antifoaming agent can be added to the resin composition for black resist of the present invention, if necessary. Examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, and the like, and a plasticizer may include dibutylphthalate, dioctylphthalate, and tricresyl. Moreover, as a defoaming agent and a leveling agent, silicone type, a fluorine type, and an acryl type compound can be mentioned, for example.

The resin composition for black resists of this invention contains the said (A)-(poly) component or these and a solvent as a main component. It is preferable that (a)-(poly) components contain 70 wt% or more in total, preferably 80 wt%, more preferably 90 wt% or more in solid content which removed the solvent (solid content contains the monomer which becomes a solid content after hardening). Do. In the resin composition, although the optimum viscosity range varies depending on the coating device used for coating, the solvent content ratio is preferably in the range of 50 to 90 wt%.

Moreover, about the color filter light shielding film of this invention, it forms by the photolithographic method using the photosensitive resin composition for black resists of this invention mentioned above. In the manufacturing process, first, the photosensitive resin composition is applied to the surface of the substrate as a solution, and then the solvent is dried (pre-bake), and then a photomask is placed on the film thus obtained, and ultraviolet light is applied. The method of irradiating, hardening an exposure part, and carrying out the phenomenon which elutes an unexposed part using aqueous alkali solution, forms a pattern, and post-bake is performed as post-drying.

As a substrate on which the solution of the photosensitive resin composition is applied, a transparent electrode such as ITO or gold is deposited or patterned on glass or a transparent film (for example, polycarbonate, polyethylene terephthalate, polyether sulfone, etc.). do,

As a method of apply | coating the solution of this photosensitive resin composition to a board | substrate, any method, such as the method of using a roller coater, a land coater, or a spinner, can be employ | adopted besides the well-known solution deposition method and the spray method. According to these methods, after apply | coating to desired thickness, a film is formed by removing a solvent (prebaking). Prebaking is performed by heating with an oven, a potplate, etc. In the prebaking, the heating temperature and the heating time are appropriately selected depending on the solvent to be used, for example, at a temperature of 80 to 120 ° C. for 1 to 10 minutes.

The exposure performed after the prebaking is performed by an exposure machine, and only the resist of the part corresponding to the pattern is exposed by exposing through a photomask. An exposure machine and its exposure irradiation conditions are appropriately selected, and exposure is performed using a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, an ultraviolet ray, or the like to photocure the resin composition for black resist in the coating film.

Alkali development after exposure is performed in order to remove the resist of the part which is not exposed, and a desired pattern is formed by this phenomenon. As a developer suitable for this alkali development, although the aqueous solution of the carbonate of an alkali metal or alkaline-earth metal, the aqueous solution of the hydroxide of an alkali metal, etc. can be mentioned, For example, carbonates, such as sodium carbonate, potassium carbonate, lithium carbonate, are 0.05-3. It is good to develop at the temperature of 20-30 degreeC using the weakly alkaline aqueous solution containing weight%, and a fine image can be formed precisely using a commercially available developer, an ultrasonic cleaner, etc.

After developing in this manner, heat treatment (post bake) is carried out at a temperature of 180 to 250 ° C and a condition of 20 to 100 minutes. This post-baking is performed for the purpose of improving the adhesiveness of a patterned light shielding film and a board | substrate. This is done by heating with an oven, potplate or the like in the same form as the prebaking. The patterned light shielding film of this invention is formed through each process by the above photolithographic method.

The resin composition for black resists of the present invention is suitable for forming fine patterns by operations such as exposure and alkali development as described above, but similarly, even if a pattern by a conventional screen printing method is formed, light blocking properties, adhesion properties, electro-optical properties, A light shielding film excellent in heat resistance and chemical resistance can be obtained.

The photosensitive resin composition for black resists of the present invention can be suitably used as a coating material, and in particular, the color filter ink used in the liquid crystal display device or the image pickup device and the light shielding film formed thereon are useful as color filters, black mattresses for liquid crystal projection, and the like. Do. Further, the photosensitive resin composition for black resists of the present invention can be used as various multicolor display ink materials such as color liquid crystal display devices, color facsimiles, image sensors, etc. in addition to color filter inks of color liquid crystal displays.

(Example)

<Preparation Examples A-1 to A-8 and a-1 to a-3 of Shading-Containing Dispersions>

Resin-coated carbon black (MS18E manufactured by Mitsubishi Chemical Corporation) and granular silica (AEROSIL manufactured by Degussa Japan Co., Ltd.) of the primary particle diameter shown in Table 1 were blended to a concentration of 20% by weight, and a polymer dispersant concentration 5 It disperse | distributed with the bead mill together with the weight% and propylene glycol monomethyl ether acetate, and it was set as dispersion liquids A-1-A-6 of 25% of solid content. Similarly, dispersions A-7 to A-8 were prepared using titanium black (manufactured by Mitsubishi Materials Corporation) or mixed organic pigment black (manufactured by Mikuni Color, Ltd.) by using carbon black.

The viscosity of the prepared dispersion liquid was measured by E-type viscometer, 20 rpm, and 25.0 +/- 0.5 degreeC. In addition, when the viscosity after 1 month standing at room temperature and after storing for 1 week at 40 degreeC, the viscosity change rate was less than 10% (it represents with ○ in a table | surface). In addition, the average value of the primary particle diameter of the light-shielding pigment and the granular silica was observed by a transmission electron microscope, and 100 particles were randomly selected to measure the long and short axis lengths of the particles and to calculate their arithmetic mean. Saved by. In addition, when agglomerating agglomerates and aggregates are comprised, a primary particle represents the particle which comprises these. In addition, the particle diameter of the light-shielding pigment and granular silica recorded in Table 1 shows the average value of the primary particle diameter obtained by the said method.

The dispersion liquid a-1 of Preparation Example 9 was a dispersion liquid containing no granular silica, and a-2 was a mixture of granular silica having an average particle diameter (average value of the primary particle diameter) of 5 nm, but the viscosity was 10% during storage. It changed as mentioned above, and there existed a fault in dispersion stability (it represents with x in a table | surface). Dispersion a-3 mixes granular silica whose average particle diameter (average value of primary particle diameter) exceeds 50 nm.

<Preparation of Photosensitive Resin Composition for Black Resist>

After mixing the dispersion and the components shown in Table 2, respectively, in the proportions indicated in the table, propylene glycol monomethyl ether acetate was added together with 0.23 parts of the silane coupling agent S-510 (manufactured by Shin-Etsu Chemical Co., Ltd.). To 100 parts by weight and a solid content concentration of 20% by weight. Further, 0,01 parts by weight of a silicone surfactant SH3775 (manufactured by KAO Corporation) was added, and the resultant was filtered under a pressure of 0.2 kg / cm 2 using a 2 µm polypropylene membrane filter to prepare a photoresist composition for black resist. In addition, each component described in the table | surface is enumerated below.

(B) -1: Propylene glycol monomethyl ether acetate solution of an acid anhydride polycondensate of epoxy acrylate having a fluorene skeleton (resin solid content concentration: 56.1 wt%, product of Nippon Steel Chemical Co., Ltd., trade name V259ME )

(B) -2: N-ethylmaleimide / methacrylic acid / benzyl methacrylate copolymer having a weight average molecular weight of 30000 and an acid value of 100 (propylene resin monomethyl ether acetate solution (solid resin concentration = 36.7% by weight)) (N-ethyl Maleimide: Methacrylic acid: Benzyl methacrylate = 29: 20: 51 mol%)

(C) -1: A mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (product of NIPPON KAYAKU CO., LTD., Trade name DPHA)

(D) -1: photopolymerization initiator, IRGACURE OXE01 from Ciba Specialty Chemicals Inc.

(D) -2: photopolymerization initiator, IRGACURE OXE02 from Ciba Specialty Chemicals Inc.

The photosensitive resin composition for black resist obtained above was apply | coated so that the thick film after post-baking might be set to 2.1 micrometer on the glass substrate of 125 mm x 125 mm using a spin coat, and prebaked at 80 degreeC for 1 minute. Thereafter, the exposure gap was adjusted to 80 µm, and a negative photomask having a line / space = 20 µm / 20 µm was put on the dry coating film, and the ultraviolet ray of 100mj / cm 2 was irradiated with an ultra-high pressure mercury lamp having an I linearity of 30 mW / cm 2. The photocuring reaction of the photosensitive portion was carried out.

Next, the exposed plate was subjected to a 1 kgf / cm 2 pressure shower at 23 ° C. in a 0.05% potassium hydroxide aqueous solution, and the time at which the pattern was observed was subtracted from the development time (BT seconds), and further developed for 20 seconds. Thereafter, spray water washing at a pressure of 5 kgf / cm 2 was performed, the unexposed part of the coating film was removed to form a pixel pattern on the glass substrate, and then hot post-baked at 230 ° C. for 30 minutes using a hot air dryer. The evaluation items and method of the black mattress obtained in each Example and the comparative example are as follows.

Coating foreign material: The case where radial streaks were observed in the coating film after spin coating was made into << defective>, and the case where it was not observed was (<good>).

Sensitivity: The exposure amount (mj / cm <2>) in which a residual film is observed in BT (break time) + 20 second using the step mask was measured.

Developing adhesiveness: The case where 20 micrometer pattern remained in BT (break time) + 40 second was made into (circle) and the thing which peeled was x.

Pattern linearity: The case where a 20 micrometer line after postbaking was observed under the microscope and an uneven state was observed was made into x and the case where it was not.

Thick film and surface roughness: Measured using a tactile film thickness meter (KLA-Tencor Corporation). Surface roughness was Ra (Å) arrange | positioned at 2 mm width on the black mattress surface.

Taper shape: At the time of developing time +10 to 30 seconds, the cross section of the 20 µm line after the post-baking is observed with an operating electron microscope, and the angle formed by the substrate and the BM taper is usually 60 ° or more, but less than 60 °. (Triangle | delta) and the case of arc shape were made into x.

Pattern adhesiveness: ○ <good> and what was recognized by the << defective> which peeling of a 20 micrometer pattern was not recognized by the peeling test.

PCT Adhesion: Post-baked pattern-forming substrate is subjected to PCT (Pressure Cooker Test) test at 121 ° C, 100% RH, 2atm and 24 hours, followed by peel test by attaching cellophane tape to 20㎛ pattern. ○ <good> and what was recognized by x <defective> were evaluated that peeling of a 20 micrometer pattern was not recognized.

OD measurement: OTSUKA ELECTRONICS CO., LTD. It measured using the OD system of a product, and described as OD value with respect to 1 micrometer.

Volume resistivity value: A 2.1-micrometer-thick coating film was formed after post-baking on the chromium-deposited glass substrate similarly to the above. A 10-mmΦ AI deposition film was formed on the coating film, a voltage of 1-10V was applied between Cr-Al, the current value was measured, and the resistance was obtained.

In Examples 1-12, the taper angle was 60 degrees or more, the wrinkle generation after postbaking was not found, and surface roughness (surface roughness Ra: JIS B0601-1994) did not exceed 120 GPa. On the other hand, in Comparative Examples 1 and 2 without granular silica, the taper was generally arc-shaped. In addition, Comparative Example 3 using silica having a 5 nm particle diameter showed poor stability of the dispersion, and radial unevenness was observed during application of black ink. In the case of Comparative Example 4 using silica having a particle diameter of 70 nm, the pattern adhesion and the PCT adhesion at the time of development were not good.

<Examples 13-16, Comparative Examples 5 and 6>

In the photosensitive resin composition used in Example 1, Comparative Example 1, and Comparative Example 2, when the exposure amount was increased to 50, 100, 150, and 200 mJ / cm 2, the surface roughness of the exposed surface after postbaking and the appearance of wrinkles were observed. The results are shown in Table 3. The embodiment in the case of containing silica was able to improve the sensitivity without any wrinkles occurring. However, in the comparative example, wrinkles became remarkable with the increase of the exposure dose, and when the sensitivity was increased, the surface roughness became larger and wrinkles occurred.

Example 17

Using the resin composition used in Examples 13-16, the mattress which has the light-shielding partition of 300 micrometer x 100 micrometers, BM line 30 micrometers, and a film thickness of 2.1 micrometers was formed. Thereafter, the mixture was treated for 3 seconds in an oxygen atmospheric pressure plasma, and then treated for 3 seconds in a CF ₄ atmospheric plasma. When the static contact angle was measured using water or butyl carbitol acetate (BCA) on this light shielding partition (light shielding film), it showed 100 degrees and 50 degrees, respectively. In this black mattress, ink of red, blue, green having a viscosity of 9 mPa.sec and a solid content concentration of 20% was printed using an inkjet head manufactured by TOSHIBA TEC CORPORATION, and post-baked at 230 ° C to form a color filter. As a result, a good color filter could be obtained.

Claims (8)

(A) A photoresist for black resists comprising a photocurable resin and / or a photocurable monomer, (B) at least one light-shielding pigment selected from black organic pigments, mixed organic pigments and light-shielding materials, and (C) granular silica. In the resin composition: The average value of the primary particle diameter of the granular silica as the (C) component is 10 to 50 nm, and the ratio ((C) / (B) of the average value of the primary particle diameter of the light-shielding pigment (B) and the granular silica (C)). ) Is in the range of 0.2 to 5.0, and the weight ratio ((C) / (B)) of the granular silica (C) and the light-shielding pigment (B) in the composition is in the range of 0.1 to 1.0. Photosensitive resin composition. The method of claim 1, The weight ratio ([(B) + (C)] / (R)) of the total weight of the light-shielding pigment (B) and the granular silica (C) to the weight of the resin solid content (R) in the composition is in the range of 0.4 to 2.2. The photosensitive resin composition for black resists characterized by the above-mentioned. The method according to claim 1 or 2, A photocurable resin as the component (A) is composed of an unsaturated group-containing compound obtained by further reacting a reaction product of an epoxy compound represented by the following general formula (1) with (meth) acrylic acid with a polybasic acid carboxylic acid or an anhydride thereof. Photosensitive resin composition for resist.

Wherein R ₁ and R ₂ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a phenyl group or a halogen atom, and X is -CO-, -SO _2- , -C (CF ₃ ) _2- , -Si (CH ₃ ) _2- , -CH _2- , -C (CH ₃ ) _2- , -O-, 9, 9-fluorenyl group represented by the following formula

Or absent, n is an integer of 0 to 10) The method according to any one of claims 1 to 3, (B) The light-shielding material of component is carbon black, The photosensitive resin composition for black resists characterized by the above-mentioned. The method according to any one of claims 1 to 4, After coating and drying on a substrate, the surface roughness (Ra) of the light shielding film obtained by making each process of (a) exposure by an ultraviolet-ray exposure apparatus, (b) image development with aqueous alkali solution, and (c) heat processing essential is 120 Pa or less. The photosensitive resin composition for black resists characterized by the above-mentioned. The method according to any one of claims 1 to 4, After coating and drying on the substrate, the volume resistivity value of the light shielding film obtained by mandatory each step of (a) exposure with an ultraviolet exposure apparatus, (b) development with an aqueous alkali solution, and (c) heat treatment is 10 ¹⁰ ? Cm. The photosensitive resin composition for black resists characterized by the above. After applying and drying the photosensitive resin composition for black resists of any one of Claims 1-6 on a transparent substrate, (a) exposure by the ultraviolet exposure apparatus, (b) image development by aqueous alkali solution, and ( c) The light shielding film obtained by making each process of heat processing essential, a light shielding film characterized by the taper angle being 60 degrees or more. The light-shielding partition as a black mattress is comprised from the light-shielding film of Claim 7, and has a film thickness of 1.5-4 micrometers, The color filter for inkjet process color filters.