JP6713746B2 - Photosensitive resin composition for light-shielding film having spacer function, light-shielding film, liquid crystal display device, method for producing photosensitive resin composition for light-shielding film having spacer function, method for producing light-shielding film, and production of liquid crystal display device Method - Google Patents

Description

The present invention relates to a photosensitive resin composition for a light-shielding film having a spacer function, and a light-shielding film having a spacer function obtained by curing the same, and more specifically, a black column spacer having both a spacer function and a black matrix function in a liquid crystal display device. The present invention relates to a photosensitive resin composition and a cured film thereof, which can be formed by a photolithography method. The present invention further relates to a liquid crystal display device using the black column spacer obtained by curing. The present invention further relates to the above-mentioned photosensitive resin composition, light-shielding film, and method for manufacturing a liquid crystal display device.

In recent years, color liquid crystal displays (LCDs) have been used in various fields such as liquid crystal televisions, liquid crystal monitors, and color liquid crystal mobile phones. Among these, in order to improve the performance of LCDs, improvements aiming at improvement of characteristics such as viewing angle, contrast, response speed, etc. are being actively made, and various thin-film transistors (TFT)-LCDs which are widely used at present are also being used. Various panel structures have been developed. Regarding TFT-LCDs, the conventional method has been mainly used to manufacture an array substrate and a color filter substrate on which TFTs are formed, and to bond both substrates with spacers kept at a constant interval, but the cost is reduced. LCD manufacturing processes aiming to improve yield have also been developed. For example, a manufacturing process has been developed in which a color filter is directly formed on a TFT of an array substrate and a glass substrate is bonded as an opposite substrate. The structure thus formed is called a color filter on TFT (COT) or the like. Also in this COT, a method of forming a black matrix, which is a boundary of each pixel of red (R), green (G), blue (B), etc., of the color filter layer formed on the TFT before forming RGB, Various LCD panel structures have been studied, such as a method of forming the pixel on the glass substrate or a method of forming the pixel on the opposite glass substrate.

One of the factors that affects the performance of the LCD, the spacer that functions to keep the thickness of the liquid crystal layer (the distance between the array substrate and the color filter substrate in the conventional method) constant, which is one factor that affects the performance of the LCD, is The method of sandwiching the ball spacer was taken. However, this method has a problem that the amount of light transmitted from each pixel is not constant because the dispersion state of the ball spacers becomes non-uniform. To solve this problem, a method of forming a column spacer by a photolithography method has been adopted. However, the column spacers formed by the photolithography method are often transparent, and in such column spacers, the light obliquely incident on the column spacers affects the electrical characteristics of the TFT and deteriorates the display quality. There is a problem. To solve such a problem, an LCD panel structure is proposed in which a light-shielding column spacer, which is a light-shielding film having a spacer function formed by a photolithography method, is applied (Patent Document 1). Also in COT, a method of forming a so-called black column spacer (BCS), in which the column spacer is formed of the same material as the black matrix, has been studied (for example, Patent Document 2).

This light-shielding column spacer requires a film thickness of about 2 to 7 μm in order to function as a spacer. In addition, it is necessary that light-shielding column spacers having different heights can be formed at the same time at the places where the TFTs are formed and other places. Further, the light-shielding column spacer is also required to have an appropriate range of elastic modulus, deformation amount, elastic recovery rate, etc. as a spacer function (Patent Document 3). In addition, the light-shielding column spacer is required to reduce the curable component by adding a light-shielding component (colorant) to the spacer and to improve the loss of electrical properties due to the influence of impurities in the colorant. (Patent Document 4).

JP, 08-234212, A U.S. Patent Application Publication No. 2009/0303407 JP, 2009-031778, A International publication 2013/062011

In Patent Document 4, a mixed color organic pigment is used, but the optical density of the light-shielding column spacer is not shown. Mixed-color organic pigments are more effective in lowering the dielectric constant than inorganic pigments such as carbon black, but often have low light-shielding properties. Further, since it is necessary to simultaneously form spacers having different heights, the light-shielding column spacer is also required to have mechanical properties such as elastic modulus, deformation amount, elastic recovery ratio and the like. The shape and mechanical properties of such spacers are greatly affected by the light-shielding component, which makes it difficult to design a photosensitive resin composition for a light-shielding film. Therefore, the shape and mechanical properties of the spacers using carbon black, mixed color organic pigments, etc. are not yet sufficient, and further improvement is required.

Further, as described above, the light-shielding column spacer is manufactured with a film thickness of about 2 to 7 μm. With the recent miniaturization of liquid crystal display elements, it is desired that the light-shielding column spacer can be formed into a fine spacer shape even if the film thickness is about 2 to 7 μm.

The present invention has been made in view of the above problems, and is a photosensitive resin for a light-shielding film having a high light-shielding property and insulating property, and further having a spacer function excellent in elastic modulus, deformation amount, and elastic recovery rate. It is to provide a composition, a light-shielding film having a spacer function formed using the composition, and a liquid crystal display device including the light-shielding film as a constituent element.

The present inventors, as a result of studies to solve the above problems in the photosensitive resin composition for a light-shielding film, as a result, a specific colorant is a light-shielding photosensitive resin composition for a light-shielding film intended They have found that they are suitable as components and have completed the present invention.

(1) The present invention relates to the following components (A) to (E), and (A) a reaction product of an epoxy compound having two glycidyl ether groups derived from bisphenols and an unsaturated group-containing monocarboxylic acid. And (b) at least a polymerizable unsaturated group-containing alkali-soluble resin obtained by reacting (a) tetracarboxylic acid or its acid dianhydride, and (b) dicarboxylic acid or tricarboxylic acid or its acid anhydride. One or more light-shielding components selected from the group consisting of a photopolymerizable monomer having one ethylenically unsaturated bond, (C) a photopolymerization initiator, (D) a black organic pigment, a mixed color organic pigment and a light-shielding material, and (E) A photosensitive resin composition for a light-shielding film having a spacer function, which contains a solvent as an essential component.
(2) The present invention is also the photosensitive resin composition according to claim 1, which contains titanium black as the light-shielding component (D).
(3) The present invention is also the photosensitive resin composition as described in (2), wherein the titanium black has an average secondary particle diameter of 100 to 300 nm.
(4) The present invention also contains (D) a light-shielding component, a black organic pigment and/or a mixed color organic pigment, and the black organic pigment and/or the mixed color organic pigment has an average secondary particle diameter of 20 to 500 nm. The photosensitive resin composition according to any one of (1) to (3), characterized in that
(5) In the present invention, the amount of the component (B) is 5 to 400 parts by mass with respect to 100 parts by mass of the component (A), and the amount of the component (C) is 100 parts by mass in total of the components (A) and (B). In contrast, when the components other than the component (E) including the component (B) that becomes the solid content after photocuring is 0.1 to 30 parts by mass as the solid content, the component (D) is included in the total solid content. 5 to 80% by mass, respectively, is the photosensitive resin composition according to any one of (1) to (4).
(6) The present invention also provides a light-shielding film having an optical density OD of 0.5/μm or more and 3/μm or less, and having a volume resistivity of 1×10 ⁹ Ω·cm or more when a voltage of 10 V is applied, and a dielectric constant. The photosensitive resin composition according to any one of (1) to (5), which is capable of forming a light-shielding film having a ratio of 2 to 10. Is.
(7) The present invention is also characterized in that, in a load-unload test using a micro hardness meter, a light-shielding film that satisfies at least one of the following (i) to (iii) can be formed, (1) to ( The photosensitive resin composition according to any one of 6).
(I) Breaking strength is 200 mN or more (ii) Elastic recovery is 30% or more (iii) Compressibility is 40% or less (8) The present invention also includes (1) to (7). (3) A light-shielding film having a spacer function, which is formed by curing the photosensitive resin composition according to any one of (1) to (4) above.
(9) The present invention is also a liquid crystal display device having the light shielding film according to (8) as a black column spacer (BCS).
(10) The present invention is the liquid crystal display device according to (9), further including a thin film transistor (TFT).
(11) In the present invention, (D) a light-shielding component is dispersed in a solvent (E) to prepare a dispersion, and then (A) an alkali-soluble resin and (B) at least one ethylenic resin. A method for producing a photosensitive resin composition for a light-shielding film having a spacer function, further comprising adding and mixing a photopolymerizable monomer having an unsaturated bond, (C) a photopolymerization initiator, and (E) a solvent. The (A) alkali-soluble resin is (a) a tetracarboxylic acid or a tetracarboxylic acid thereof against a reaction product of an epoxy compound having two glycidyl ether groups derived from bisphenols and an unsaturated group-containing monocarboxylic acid. It is an alkali-soluble resin obtained by reacting an acid dianhydride and (b) a dicarboxylic acid or a tricarboxylic acid or an acid anhydride thereof, and (D) the light-shielding component comprises a black organic pigment, a mixed-color organic pigment and a light-shielding material. The method is one or more components selected from the group consisting of:
(12) The present invention is also the method according to (11), characterized in that the light-shielding component (D) contains titanium black.
(13) The present invention is also the method according to (12), characterized in that, in the dispersion, the average secondary particles of the titanium black are 100 to 300 nm.
(14) In the present invention, the light-shielding component (D) contains a black organic pigment and/or a mixed color organic pigment, and the average secondary particle diameter of the black organic pigment and/or the mixed color organic pigment in the dispersion is 20. It is a method in any one of (11)-(13) characterized by being -500 nm.
(15) The present invention is also formed on a substrate, which comprises applying the photosensitive resin composition according to any one of (1) to (7) to a substrate and curing the photosensitive resin composition by light irradiation. And a method of manufacturing a light shielding film.
(16) The present invention is also the method for producing a light-shielding film according to (15), which has a film thickness H1 for adjusting the optical density of the light-shielding film to 0.5/μm or more and less than 3/μm, and a spacer function. With respect to the film thickness H2 of the light-shielding film that plays a role in H2, when H2 is 2 to 7 μm, the light-shielding film having the film thickness H1 and the film thickness H2 in which ΔH=H2-H1 is 0.1 to 2.9 is simultaneously formed. And a method for manufacturing a light-shielding film.
(17) The present invention is also the method of manufacturing a liquid crystal display device, characterized in that the light-shielding film manufactured by the method described in (16) is used as a black column spacer.
(18) The present invention is also the manufacturing method according to (17), wherein the liquid crystal display device has a thin film transistor (TFT).

Since the photosensitive resin composition for a light-shielding film according to the present invention contains a specific colorant, the elastic modulus, the amount of deformation, and the elastic recovery while maintaining the light-shielding property and the insulating property as compared with the conventional photosensitive resin composition. A cured product having an excellent rate can be obtained. Furthermore, the photosensitive resin composition for a light-shielding film according to the present invention can form a fine spacer shape even when the film thickness is about 2 to 7 μm.

Hereinafter, the present invention will be described in detail.
The polymerizable unsaturated group-containing alkali-soluble resin as the component (A) is an epoxy compound having two glycidyl ether groups derived from bisphenols, preferably an epoxy compound represented by the general formula (I), ) Acrylic acid (which means "acrylic acid and/or methacrylic acid") is reacted with a hydroxyl group-containing compound (c) containing a polymerizable unsaturated group, and (a) a tetracarboxylic acid. Alternatively, it is an alkali-soluble resin having a carboxyl group and a polymerizable unsaturated group in one molecule, which is obtained by reacting an acid dianhydride thereof and (b) a dicarboxylic acid or a tricarboxylic acid or an acid anhydride thereof. Since the component (A) has both a polymerizable unsaturated double bond and a carboxyl group, it imparts excellent photocurability, good developability and patterning characteristics to the photosensitive resin composition, and improves the physical properties of the light shielding film.

However, in the general formula (I), R ₁ , R ₂ , R ₃ and R ₄ independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom or a phenyl group, and X is —CO— _{, -SO 2 -, - C (} CF 3) 2 -, - Si (CH 3) 2 -, - CH 2 -, - C (CH 3) 2 -, - O-, or, 9,9- It represents a diyl group or a single bond, and the average value of m is in the range of 0 to 10, preferably 0 to 3.

Examples of the bisphenols giving the epoxy compound of the general formula (I) include 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)hexafluoro Propane, 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-3,5-dichlorophenyl) ether, 9,9-bis(4-hydroxyphenyl)fluorene, 9, 9-bis(4-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-dibromophenyl)fluorene, 4,4'-biphenol, 3,3'- Biphenol etc. are mentioned. These bisphenols may be used alone or in combination of two or more. Among these, bisphenols in which X in the general formula (I) is a fluorene-9,9-diyl group can be particularly preferably used.

The compound of the general formula (I) for deriving the alkali-soluble resin (A) is an epoxy compound having two glycidyl ether groups, which is obtained by reacting the bisphenols with epichlorohydrin. During this reaction, generally, diglycidyl ether compound is oligomerized, and m is an integer of 0 to 10 in each molecule, and usually an average value of 0 to 10 (because a plurality of molecules are mixed. However, the average value of m is preferably 0 to 3. When the average value of m exceeds the upper limit, the viscosity of the composition becomes too large when the photosensitive resin composition is prepared by using the alkali-soluble resin synthesized by using the epoxy compound, and the coating may not be successful. However, alkali solubility cannot be sufficiently imparted, and alkali developability becomes extremely poor.

Next, the hydroxyl group-containing compound (c) containing a polymerizable unsaturated group obtained by the reaction of an epoxy compound and (meth)acrylic acid is reacted with an acid component to form a carboxyl group and a carboxyl group in one molecule. An alkali-soluble resin having a polymerizable unsaturated group can be obtained. As the acid component, it is preferable to use tetracarboxylic acid or its acid dianhydride (a) which can react with a compound containing a hydroxyl group, and dicarboxylic acid or tricarboxylic acid or its acid monoanhydride (b). The carboxylic acid residue of this acid component may have either a saturated hydrocarbon or an unsaturated hydrocarbon. Further, these carboxylic acid residues may contain a bond containing a hetero element such as —O—, —S—, carbonyl group and the like.

Specific examples of the acid component are shown below, but dianhydrides and monoanhydrides of the exemplified polyvalent carboxylic acids can also be used.

First, as the (a) tetracarboxylic acid, a chain hydrocarbon tetracarboxylic acid, an alicyclic tetracarboxylic acid or an aromatic polyvalent carboxylic acid can be mentioned. Here, as the chain hydrocarbon tetracarboxylic acid, there are, for example, butanetetracarboxylic acid, pentanetetracarboxylic acid, hexanetetracarboxylic acid and the like, and further, tetracarboxylic acid into which an arbitrary substituent is introduced may be used. Further, as the alicyclic tetracarboxylic acid, for example, cyclobutane tetracarboxylic acid, cyclopentane tetracarboxylic acid, cyclohexane tetracarboxylic acid, cycloheptane tetracarboxylic acid, norbornane tetracarboxylic acid, and the like, further optional substituents It may be a tetracarboxylic acid introduced with. Furthermore, examples of the aromatic tetracarboxylic acid include, for example, pyromellitic acid, benzophenonetetracarboxylic acid, biphenyltetracarboxylic acid, biphenylethertetracarboxylic acid, and the like. Good. These (a) tetracarboxylic acids may be used alone or in combination of two or more.

As the (b) dicarboxylic acid or tricarboxylic acid, a chain hydrocarbon dicarboxylic acid or tricarboxylic acid, an alicyclic dicarboxylic acid or tricarboxylic acid, an aromatic dicarboxylic acid or tricarboxylic acid is used. Here, as the chain hydrocarbon dicarboxylic acid or tricarboxylic acid, for example, succinic acid, acetylsuccinic acid, maleic acid, adipic acid, itaconic acid, azelaic acid, citramalic acid, malonic acid, glutaric acid, citric acid, tartaric acid, There are oxoglutaric acid, pimelic acid, sebacic acid, suberic acid, diglycolic acid and the like, and further, a dicarboxylic acid or a tricarboxylic acid into which an arbitrary substituent is introduced may be used. Further, examples of the alicyclic dicarboxylic acid or tricarboxylic acid include cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, norbornanedicarboxylic acid and the like, and further arbitrary substituents have been introduced. It may be a dicarboxylic acid or a tricarboxylic acid. Further, examples of the aromatic dicarboxylic acid or tricarboxylic acid include phthalic acid, isophthalic acid, trimellitic acid and the like, and further, a dicarboxylic acid or tricarboxylic acid having an arbitrary substituent introduced therein may be used. These (b) dicarboxylic acids or tricarboxylic acids may be used alone or in combination of two or more.

The molar ratio (b)/(a) of (a) tetracarboxylic acid or its acid dianhydride and (b) dicarboxylic acid or tricarboxylic acid or its acid anhydride used in the alkali-soluble resin of (A) is It is 0.01 to 0.5, preferably 0.02 or more and less than 0.1. When the molar ratio (b)/(a) deviates from the above range, the optimum molecular weight for obtaining the photosensitive resin composition of the present invention having high light-shielding and high resistance and good photopatternability cannot be obtained. Therefore, it is not preferable. The smaller the molar ratio (b)/(a), the greater the alkali solubility and the greater the molecular weight.

Regarding the ratio of reacting the hydroxyl group-containing compound (c) containing a polymerizable unsaturated group with the acid components (b) and (a), it is preferable that the terminal of the compound be a carboxyl group. It is desirable to react quantitatively so that the molar ratio of the components is (c):(b):(a)=1:0.2-1.0:0.01-1.0. In this case, the molar ratio of the total amount of the acid component to the hydroxyl group-containing compound (c) containing a polymerizable unsaturated group (c)/[(b)/2+(a)]=0.5 to 1.0. It is desirable to react quantitatively. If this molar ratio is less than 0.5, the end of the alkali-soluble resin becomes an acid anhydride, and the content of unreacted acid dianhydride increases, which may deteriorate the stability of the alkali-soluble resin composition over time. To be done. On the other hand, when the molar ratio exceeds 1.0, the content of the hydroxyl group-containing compound containing the unreacted polymerizable unsaturated group increases, and there is a concern that the stability of the alkali-soluble resin composition may deteriorate over time. The molar ratio of each of the components (a), (b) and (c) can be arbitrarily changed within the above range for the purpose of adjusting the acid value and the molecular weight of the alkali-soluble resin.

The alkali-soluble resin (A) can be produced by the above-mentioned procedure by a known method, for example, the method described in JP-A 8-278629 or JP-A 2008-9401. First, as a method of reacting (meth)acrylic acid with an epoxy compound of the general formula (I), for example, (meth)acrylic acid in an equimolar amount to the epoxy group of the epoxy compound is added to a solvent, and a catalyst (triethylbenzyl) is added. In the presence of ammonium chloride, 2,6-diisobutylphenol, etc., there is a method of reacting by heating and stirring at 90 to 120° C. while blowing air. Next, as a method of reacting an acid anhydride with a hydroxyl group of an epoxy acrylate compound which is a reaction product, a predetermined amount of an epoxy acrylate compound, an acid dianhydride and an acid monoanhydride is added to a solvent, and a catalyst (odor In the presence of tetraethylammonium chloride, triphenylphosphine, etc.), the reaction is carried out by heating and stirring at 90 to 140° C.

The alkali-soluble resin (A) thus produced has a structure represented by the general formula (II), for example.

In the formula, R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom or a phenyl group, and R ₅ represents a hydrogen atom or a methyl group. represents, X _{is, -CO -, - SO 2 -} , - C (CF 3) 2 -, - Si (CH 3) 2 -, - CH 2 -, - C (CH 3) 2 -, - O-, Represents a fluorene-9,9-diyl group or a direct bond, Y represents a tetravalent carboxylic acid residue, Z is each independently a hydrogen atom or -OC-W-(COOH) _l (where W is Represents a divalent or trivalent carboxylic acid residue, 1 represents a number of 1 to 2), and n represents a number of 1 to 20.

The weight average molecular weight (Mw) in terms of polystyrene of the alkali-soluble resin (A) measured by gel permeation chromatography (GPC) is usually 1,000 to 100,000, and preferably 2,000 to 20,000. When the weight average molecular weight is less than 1000, the adhesiveness of the pattern during alkali development may be reduced, and when the weight average molecular weight is more than 100,000, the developability may be significantly reduced.

Moreover, the preferable range of the acid value of the alkali-soluble resin (A) is 80 to 120 mgKOH/g. If this value is less than 80 mgKOH/g, a residue tends to remain during alkali development, and if it exceeds 120 mgKOH/g, permeation of the alkali developing solution becomes too fast and peeling development occurs, which is not preferable either. The polymerizable unsaturated group-containing alkali-soluble resin (A) may be used alone or in a mixture of two or more.

In the present invention, as the weight average molecular weight of (A), a value obtained by dissolving the sampled solution in tetrahydrofuran and measuring the molecular weight distribution with HLC-8220GPC manufactured by Tosoh Corporation and calculating the weight average molecular weight in terms of standard polystyrene is used. As the acid value of the component A, a value obtained by dissolving the sampled solution in dioxane, neutralizing titration with a 0.1 N potassium hydroxide aqueous solution, and calculating the acid value of the sample solution in terms of solid content is used. ..

Next, as the photopolymerizable monomer having at least one ethylenically unsaturated bond (B), for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxyhexyl (meth ) Acrylic ester-containing (meth)acrylic acid esters, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tetra Methylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, Of dipentaerythritol tetra(meth)acrylate, glycerol(meth)acrylate, sorbitol penta(meth)acrylate, dipentaerythritol penta(meth)acrylate, or dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, phosphazene Alkylene oxide-modified hexa(meth)acrylate, caprolactone-modified dipentaerythritol hexa(meth)acrylate and other (meth)acrylic acid esters, pentaerythritol, dipentaerythritol and other polyhydric alcohols, phenol novolac and other polyhydric phenols Examples thereof include addition polymers of divinyl compounds such as vinylbenzyl ether compound and divinylbenzene. These (B) photopolymerizable monomers having at least one ethylenically unsaturated bond may be used alone or in combination of two or more. The photopolymerizable monomer (B) having at least one ethylenically unsaturated bond does not have a free carboxy group.

The blending ratio of the component (B) is preferably 5 to 400 parts by mass, and more preferably 10 to 150 parts by mass with respect to 100 parts by mass of the component (A). When the blending ratio of the component (B) is more than 400 parts by mass relative to 100 parts by mass of the component (A), the cured product after photocuring becomes brittle, and the acid value of the coating film in the unexposed part is low. There is a problem that the solubility in an alkaline developer is lowered and the pattern edge is not sharp and sharp. On the other hand, when the blending ratio of the component (B) is less than 5 parts by mass with respect to 100 parts by mass of the component (A), the proportion of the photoreactive functional group in the resin is small and the formation of the crosslinked structure is not sufficient. Since the resin component has a high acid value, the solubility in the exposed portion with respect to the alkali developing solution becomes high, so that the formed pattern becomes thinner than the target line width, or the pattern is apt to be missing. Problems can occur.

Examples of the photopolymerization initiator as the component (C) include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, p-tert-butyl. Acetophenones such as acetophenone, benzophenone, 2-chlorobenzophenone, benzophenones such as p,p'-bisdimethylaminobenzophenone, benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin ether ethers such as isobutyl ether, 2- (o-Chlorophenyl)-4,5-phenylbiimidazole, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5-diphenyl Biimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, 2,4,5-triarylbiimidazole and other biimidazole compounds, 2-trichloromethyl-5-styryl-1,3 ,4-Oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4 -Halomethyldiazole compounds such as oxadiazole, 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-1,3 ,5-Triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl)-1,3,5 -Triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-1 ,3,5-Triazine, 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(3,4,5-trimethoxystyryl)-4, Halomethyl-s-triazine system such as 6-bis(trichloromethyl)-1,3,5-triazine and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine Compounds, 1,2-octanedione, 1-[4-(phenylthio)phenyl]-,2-(O-benzoyloxime), 1-(4-phenyl Rusulfanylphenyl)butane-1,2-dione-2-oxime-O-benzoate, 1-(4-methylsulfanylphenyl)butane-1,2-dione-2-oxime-O-acetate, 1-(4 -Methylsulfanylphenyl)butan-1-one oxime-O-acetate, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime ), methanone, (9-ethyl-6-nitro-9H-carbazol-3-yl)[4-(2-methoxy-1-methylethoxy)-2-methylphenyl]-,O-acetyloxime, methanone, ( 2-Methylphenyl) (7-nitro-9,9-dipropyl-9H-fluoren-2-yl)-, acetyloxime, ethanone, 1-[7-(2-methylbenzoyl)-9,9-dipropyl-9H -Fluoren-2-yl]-,1-(O-acetyloxime), ethanone, 1-(-9,9-dibutyl-7-nitro-9H-fluoren-2-yl)-,1-O-acetyloxime O-acyl oxime compounds such as benzyldimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, and other sulfur compounds, 2 -Anthraquinones such as ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone and 2,3-diphenylanthraquinone, organic peroxides such as azobisisobutylnitrile, benzoyl peroxide and cumene peroxide, 2-mercaptobenzimidazole , 2-mercaptobenzoxazole, 2-mercaptobenzothiazole, and other thiol compounds. Among these, O-acyl oxime compounds are preferably used from the viewpoint of easily obtaining a highly sensitive photosensitive resin composition for a light-shielding film. These (C) photopolymerization initiators may be used alone or in combination of two or more. The photopolymerization initiator as used in the present invention is meant to include a sensitizer.

These photopolymerization initiators and sensitizers can be used alone or in combination of two or more. Further, a compound which does not act as a photopolymerization initiator or a sensitizer by itself but which can increase the ability of the photopolymerization initiator or the sensitizer when used in combination can be added. Examples of such compounds include tertiary amines such as triethanolamine and triethylamine, which are effective when used in combination with benzophenone.

The amount of the photopolymerization initiator used as the component (C) is preferably 0.1 to 30 parts by mass, and preferably 1 to 25 parts by mass, based on 100 parts by mass of the total of the components (A) and (B). Good part. When the blending ratio of the component (C) is less than 0.1 parts by mass, the photopolymerization rate becomes slow and the sensitivity decreases, while when it exceeds 30 parts by mass, the sensitivity is too strong. There is a possibility that the pattern line width becomes thicker than the pattern mask, the line width faithful to the mask cannot be reproduced, or the pattern edge is not sharp and sharp.

The component (D) is a light-shielding component selected from black organic pigments, mixed-color organic pigments and light-shielding materials, and preferably has excellent insulating properties, heat resistance, light resistance and solvent resistance. Here, examples of black organic pigments include perylene black, aniline black, cyanine black, and lactam black. Examples of the mixed color organic pigment include those obtained by mixing two or more kinds of pigments selected from red, blue, green, violet, yellow, cyanine, magenta and the like to give a pseudo black color. Examples of the light shielding material include carbon black, chromium oxide, iron oxide, titanium black and the like. These (D) light-shielding components may be used alone or in combination of two or more.

As the light-shielding material, titanium black is preferable in terms of good light-shielding properties, elastic modulus, deformation amount, and elastic recovery rate. When titanium black is used, a black organic pigment and/or a mixed color organic pigment may be used together for the purpose of further improving the insulating property. As described above, when the inorganic light-shielding material and the organic pigment are used in combination, the mixing ratio of [light-shielding material/(black organic pigment and/or mixed color organic pigment)] is 90/10 to 10/90 by mass ratio. It is preferable that it is 70/30 to 30/70. A light-shielding film having a spacer function having desired light-shielding properties and insulating properties can be obtained by such a combination of the light-shielding material and the organic pigment and their compounding ratio. For the purpose of controlling the chromaticity of the light-shielding film such as making the light-shielding film achromatic, it is possible to add an organic pigment other than black as a single color instead of the purpose of blackening by pseudo-color mixing.

Titanium black used in the present invention is a titanium-containing black inorganic pigment typified by low-order titanium oxide, titanium oxynitride and the like, and among these, those exhibiting high insulation properties can be preferably used. These titanium blacks can be produced by heating a mixture of titanium dioxide and metallic titanium in a reducing atmosphere to reduce the mixture (Japanese Patent Laid-Open No. 49-5432), and ultra-high-temperature hydrolysis of titanium tetrachloride. A method of reducing fine titanium dioxide in a reducing atmosphere containing hydrogen (JP-A-57-205322), a method of reducing titanium dioxide or titanium hydroxide at high temperature in the presence of ammonia (JP-A-60-65069, JP-A-61-201610), a method of adhering a vanadium compound to titanium dioxide or titanium hydroxide and performing high-temperature reduction in the presence of ammonia (JP-A-61-201610), and the like, but are not limited to these. Not something.

Further, these titanium-containing black inorganic pigments may have inorganic particles whose surfaces are coated with an organic compound or an inorganic compound. Examples of organic compounds used for coating are polyhydric alcohols, alkanolamines or their derivatives, organosilicon compounds (polysiloxanes, silane coupling agents, etc.), higher fatty acids or metal salts thereof, organometallic compounds (titanium compounds). Coupling agents, aluminum-based coupling agents, etc.). On the other hand, examples of inorganic compounds used for coating include aluminum compounds, silicon compounds, zirconium compounds, tin compounds, titanium compounds and antimony compounds. As a method for coating the surface of the titanium-containing particles, the method described in JP-A-2006-206891 can be used.

Examples of commercially available titanium black include titanium black 12S, 13M-T, 13M-C, UF8 manufactured by Mitsubishi Materials, and Tilack D manufactured by Ako Kasei (“Tilack D” is a registered trademark of the same company).

As the organic pigment used in the present invention, known compounds can be used without particular limitation, but those having a specific surface area according to the BET method of 50 m ² /g or more, which have been subjected to atomization processing, are preferable. Specifically, azo pigments, condensed azo pigments, azomethine pigments, phthalocyanine pigments, quinacridone pigments, isoindolinone pigments, isoindoline pigments, dioxazine pigments, slene pigments, perylene pigments, perinone pigments, quinophthalone pigments, diketopyrrolopyrrole pigments, Examples thereof include thioindigo pigments, and specifically, C.I. I. Name compounds are included, but are not limited to.
C. I. Pigment Red 2, 3, 4, 5, 9, 12, 14, 22, 23, 31, 38, 112, 122, 144, 146, 147, 149, 166, 168, 170, 175, 176, 177, 178. 179, 184, 185, 187, 188, 202, 207, 208, 209, 210, 213, 214, 220, 221, 242, 247, 253, 254, 255, 256, 257, 262, 264, 266, 272. 279 mag;
C. I. Pigment Orange 5, 13, 16, 34, 36, 38, 43, 61, 62, 64, 67, 68, 71, 72, 73, 74, 81 and the like;
C. I. Pigment Yellow 1, 3, 12, 13, 14, 16, 17, 55, 73, 74, 81, 83, 93, 95, 97, 109, 110, 111, 117, 120, 126, 127, 128, 129. , 130, 136, 138, 139, 150, 151, 153, 154, 155, 173, 174, 175, 176, 180, 181, 183, 185, 191, 194, 199, 213, 214, etc.;
C. I. Pigment Green 7, 36, 58, etc.;
C. I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 60, 80, etc.;
C. I. Pigment Violet 19, 23, 37 and the like.

Examples of the solvent of the component (E) include methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol, 3-methoxy-1-butanol, ethylene glycol monobutyl ether, 3-hydroxy-2-butanone, Alcohols such as diacetone alcohol, terpenes such as α- or β-terpineol, ketones such as acetone, methyl ethyl ketone, cyclohexanone and N-methyl-2-pyrrolidone, aromatic carbonization such as toluene, xylene and tetramethylbenzene Hydrogen, cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, Glycol ethers such as triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethyl acetate, butyl acetate, ethyl lactate, 3-methoxybutyl acetate, 3-methoxy-3-butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve Esters such as acetate, carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, etc. can be mentioned. It can be a composition in the form of a solution. Two or more kinds of these solvents may be used in order to obtain necessary properties such as coatability.

Then, these light-shielding components are preferably dispersed in a solvent together with a (F) dispersant in advance to form a light-shielding dispersion liquid, and then blended as a photosensitive resin composition for a light-shielding film. Here, since the solvent to be dispersed becomes a part of the component (E), any of those listed above as the component (E) can be used. For example, propylene glycol monomethyl ether acetate, 3-methoxybutyl. Acetate or the like is preferably used. Regarding the blending ratio of the light-shielding component (D) forming the light-shielding dispersion, it is used in the range of 5 to 80% by mass based on the total solid content of the photosensitive resin composition for a light-shielding film of the present invention. Good. In addition, the said solid content means the component except a component (E) among compositions. The solid content also includes the component (B) that becomes a solid content after photocuring. If it is less than 5% by mass, the desired light-shielding property cannot be set. When it exceeds 80% by mass, the content of the photosensitive resin serving as the original binder is reduced, so that the development characteristics are impaired and the film forming ability is impaired, which is an undesirable problem.

The average particle size (hereinafter referred to as “average secondary particle size”) of the light-shielding component in this light-shielding dispersion measured by a laser diffraction/scattering type particle size distribution meter is preferably as follows. When titanium black is used, the average secondary particle size of titanium black is preferably 100 to 300 nm, and when a black organic pigment and/or a mixed color organic pigment and/or a monochromatic organic pigment is used, the dispersion The average secondary particle size of the particles is preferably 20 to 500 nm. Even in the photosensitive resin composition for a light-shielding film prepared by blending these light-shielding dispersion liquids, these light-shielding components preferably have the same average secondary particle diameter.

Further, the (F) dispersant is used in the light-shielding dispersion in order to stably disperse the light-shielding component, and known dispersants such as various polymer dispersants can be used for this purpose. .. As an example of the dispersant, known compounds conventionally used for pigment dispersion (such as compounds commercially available under the names of dispersant, dispersion wetting agent, dispersion accelerator, etc.) can be used without particular limitation. Examples thereof include cationic polymer dispersants, anionic polymer dispersants, nonionic polymer dispersants, pigment derivative type dispersants (dispersion aids), and the like. In particular, it has a cationic functional group such as an imidazolyl group, a pyrrolyl group, a pyridyl group, a primary, secondary or tertiary amino group as an adsorption point on the pigment, and has an amine value of 1 to 100 mgKOH/g and a number average molecular weight. A cationic polymer dispersant having a ratio of 1,000 to 100,000 is suitable. The amount of the dispersant blended is preferably 1 to 30% by mass, and more preferably 2 to 25% by mass, based on the light-shielding component.

Further, when preparing the light-shielding dispersion liquid, a part of the polymerizable unsaturated group-containing alkali-soluble resin of the component (A) is co-dispersed in addition to the above-mentioned dispersant to obtain a photosensitive resin composition for a light-shielding film. When used as a product, it is possible to easily maintain the exposure sensitivity at a high sensitivity, to obtain a photosensitive resin composition which has good adhesiveness during development and is less likely to cause a problem of residue. The content of the component (A) in the light-shielding dispersion is preferably 2 to 20% by mass, more preferably 5 to 15% by mass. When the content of the component (A) is less than 2% by mass, the co-dispersed effects such as improved sensitivity, improved adhesion and reduced residue cannot be obtained. Further, when the content is 20% by mass or more, especially when the content of the light shielding material is large, the viscosity of the light shielding dispersion liquid is high, and it is difficult or extremely time-consuming to disperse the light shielding dispersion liquid uniformly, and thus it is possible to uniformly shield light. It becomes difficult to obtain a photosensitive resin composition for obtaining a coating film in which the components are dispersed.

The light-shielding dispersion liquid thus obtained contains the component (A) (the remaining component (A) when the component (A) is co-dispersed when preparing the light-shielding dispersion liquid), (B). By mixing the component, the component (C), and the remaining component (E), a photosensitive resin composition for a light shielding film can be obtained.

Further, the photosensitive resin composition of the present invention, if necessary, a curing accelerator, a thermal polymerization inhibitor and an antioxidant, a plasticizer, a filler, a solvent, a leveling agent, a defoaming agent, a coupling agent, an interface. Additives such as activators can be added. Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, hindered phenol compounds, and the like.Plasticizers include dibutyl phthalate, dioctyl phthalate, and phosphorus. Examples of the filler include glass fiber, silica, mica, and alumina. Examples of the defoaming agent and leveling agent include silicone-based, fluorine-based, and acrylic-based compounds. be able to. Further, examples of the surfactant include a fluorine-based surfactant and a silicone-based surfactant, and examples of the coupling agent include 3-(glycidyloxy)propyltrimethoxysilane, 3-acryloxypropyltrimethoxysilane, Examples thereof include silane coupling agents such as 3-isocyanatopropyltriethoxysilane and 3-ureidopropyltriethoxysilane.

The photosensitive resin composition of the present invention may be used in combination with other resin components that are polymerized or cured by heat. As the other resin component, (G) an epoxy resin or an epoxy compound having two or more epoxy groups is preferable, and 3,3′,5,5′-tetramethyl-4,4′-biphenol type epoxy resin, bisphenol A type epoxy resin, bisphenolfluorene type epoxy resin, phenol novolac type epoxy resin, 3,4-epoxycyclohexenylmethyl-3',4'-epoxycyclohexenecarboxylate, 2,2-bis(hydroxymethyl)-1-butanol 1,2-epoxy-4-(2-oxiranyl)cyclohexane adduct, epoxy silicone resin, and the like. These additional components may be used alone or in combination of two or more.

The photosensitive resin composition of the present invention contains the above components (A) to (E) as main components. It is desirable that the total amount of the components (A) to (D) is 70% by mass, preferably 80% by mass or more, in the solid content. The amount of the solvent (E) varies depending on the target viscosity, but it is preferable that the amount of the solvent (E) be contained in the photosensitive resin composition in the range of 60 to 90 mass %.

The photosensitive resin composition for a light-shielding film of the present invention is excellent as a photosensitive resin composition for forming a light-shielding film having a spacer function, for example. As a method of forming the light-shielding film having a spacer function, there is the following photolithography method. First, the photosensitive resin composition for a light-shielding film in the present invention is applied onto a substrate, then the solvent is dried (prebaking), and then a photomask is applied onto the film thus obtained, and ultraviolet rays are applied. Is applied to cure the exposed area, and the unexposed area is eluted with an alkaline aqueous solution to form a pattern, and post-drying (thermal baking) is performed as post-drying.

The base material may be a transparent substrate, or a transparent substrate such as an alignment film formed on a pixel, a flattening film on the pixel, or a flat film on the pixel after forming pixels such as RGB. Other base materials may be used. The type of substrate on which the light shielding film having the spacer function is formed depends on the design of the liquid crystal display device.

As the transparent substrate for applying the photosensitive resin composition, in addition to a glass substrate, a transparent film (for example, polycarbonate, polyethylene terephthalate, polyether sulfone, etc.) on which a transparent electrode such as ITO or gold is vapor-deposited or patterned, etc. Can be illustrated. As a method for applying the solution of the photosensitive resin composition on the transparent substrate, any of known solution dipping method, spray method, roller coater machine, land coater machine, slit coater machine, spinner machine and the like can be used. The method can also be adopted. By these methods, after coating to a desired thickness, the solvent is removed (prebaking) to form a film. Prebaking is performed by heating with an oven, a hot plate, or the like. The heating temperature and the heating time in the pre-baking are appropriately selected according to the solvent used, and for example, the heating is performed at a temperature of 60 to 110° C. for 1 to 3 minutes.

The exposure performed after the prebaking is performed by an ultraviolet exposure device, and only the resist corresponding to the pattern is exposed by exposing through the photomask. The exposure apparatus and its exposure irradiation conditions are appropriately selected, and light exposure is performed using a light source such as an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, a far ultraviolet ray lamp, and the photosensitive resin composition in the coating film is photocured.

The alkali development after exposure is performed for the purpose of removing the resist in the unexposed portion, and a desired pattern is formed by this development. Examples of the developer suitable for the alkali development include an aqueous solution of a carbonate of an alkali metal or an alkaline earth metal, an aqueous solution of an alkali metal hydroxide, and the like, and particularly sodium carbonate, potassium carbonate, lithium carbonate. It is preferable to develop at a temperature of 23 to 28° C. using a weak alkaline aqueous solution containing 0.05 to 3 mass% of a carbonate such as, and a fine image can be obtained by using a commercially available developing machine or an ultrasonic cleaner. It can be precisely formed.

After the development, heat treatment (post-baking) is preferably performed at a temperature of 180 to 250° C. for 20 to 60 minutes. This post-baking is performed for the purpose of increasing the adhesion between the patterned light-shielding film and the substrate. This is performed by heating with an oven, a hot plate or the like as in the pre-baking. The patterned light-shielding film of the present invention is formed through the steps of the photolithography method described above.

According to the above method, a light-shielding film having an optical density of 0.5/μm to 3/μm, preferably 1.5/μm to 2.5/μm can be formed. Further, according to the above method, it is possible to form a light-shielding film having a volume resistivity of 1×10 ⁹ Ω·cm or more, preferably 1×10 ¹² Ω·cm or more when a voltage of 10 V is applied. Further, according to the above method, a light-shielding film having a dielectric constant of 2 to 10, preferably 2 to 8, and more preferably 3 to 6 can be formed. Further, according to the above method, it is possible to form a light-shielding film which has a breaking strength of 200 mN or more and/or an elastic recovery rate of 30% or more and/or a compression rate of 40% or less in a mechanical property test. .. The light-shielding film formed by the above method can be used as a column spacer of a liquid crystal display device, preferably a black column spacer.

Further, according to the above method, with respect to the film thickness H1 for making the optical density of the light shielding film 0.5/μm or more and less than 3/μm, and the film thickness H2 of the light shielding film having a spacer function, H2 is 2 to 2 When the thickness is 7 μm, it is possible to simultaneously form a light-shielding film having a film thickness H1 and a light-shielding film having a film thickness H2 in which ΔH=H2-H1 is 0.1 to 2.9. The cured film formed by the above method can be used as a column spacer of a liquid crystal display device, preferably a black column spacer. With the cured film having ΔH in the above range, the black column spacers having different heights can be formed at the same time from the same material, so that the liquid crystal display device can be manufactured more efficiently. At this time, for example, the cured film having the film thickness H2 may function as a spacer and the cured film having the film thickness H1 may function as a black matrix. The reason why ΔH is necessary is that if the film having the black matrix function is made to have the same film thickness as the film having the spacer function, the liquid crystal layer is divided for each pixel, which prevents the liquid crystal layer from freely flowing. In addition, it is feared that the yield when the liquid crystal layer is filled with the liquid crystal display device is reduced.

The liquid crystal display device having the light-shielding film or the cured film is preferably a TFT-LCD provided with a thin film transistor.

The liquid crystal display device having the above-mentioned light-shielding film or cured film has a high light-shielding property and insulating property, further has a spacer function excellent in elastic modulus, deformation amount, and elastic recovery rate, and has a film thickness of about 2 to 7 μm. Even in this case, a fine spacer shape can be formed.

Hereinafter, embodiments of the present invention will be specifically described based on Examples and Comparative Examples, but the present invention is not limited thereto.

First, a synthesis example of the (A) polymerizable unsaturated group-containing alkali-soluble resin of the present invention will be shown. Evaluation of the resin in the synthesis example was performed as follows.

[Solid content concentration]
A glass filter [weight: W ₀ (g)] was impregnated with 1 g of the resin solution obtained in the synthesis example, weighed [W ₁ (g)], and the weight [W ₂ ( g)] from the following equation.
Solid content concentration (% by weight)=100×(W ₂ −W ₀ )/(W ₁ −W ₀ ).

[Acid value]
The resin solution was dissolved in dioxane and titrated with a 1/10 N-KOH aqueous solution using a potentiometric titrator [manufactured by Hiranuma Sangyo Co., Ltd., trade name COM-1600].

[Molecular weight]
Gel permeation chromatography (GPC) [Tosoh Corporation trade name HLC-8220GPC, solvent: tetrahydrofuran, column: TSKgelSuperH-2000 (2) + TSKgelSuperH-3000 (1) + TSKgelSuperH-4000 (1) + TSKgelSuper-H5000 (1 piece) [manufactured by Tosoh Corporation], temperature: 40° C., speed: 0.6 ml/min], and the weight average molecular weight (Mw) as standard polystyrene [Tosoh Corporation PS-Oligomer Kit] conversion value I asked.

[Measurement of average secondary particle size]
A particle size distribution analyzer (manufactured by Nikkiso Co., Ltd., Microtrac MT-3000, manufactured by Nikkiso Co., Ltd.) was used for a solution in which the light-shielding dispersion was diluted with a solvent (PGMEA in this example) and the concentration of the light-shielding component was about 0.1% by mass. ) Was used to measure the average secondary particle size.

The abbreviations used in Synthesis Examples and Comparative Synthesis Examples are as follows.
BPFE: A reaction product of 9,9-bis(4-hydroxyphenyl)fluorene and chloromethyloxirane. The compound of the general formula (I), wherein X is fluorene-9,9-diyl, and R ₁ and R ₂ are hydrogen.
BPDA: 3,3',4,4'-biphenyltetracarboxylic dianhydride
BTDA: 3,3',4,4'-benzophenone tetracarboxylic dianhydride
THPA: 1,2,3,6-tetrahydrophthalic anhydride
TPP: Triphenylphosphine
PGMEA: Propylene glycol monomethyl ether acetate

[Synthesis example 1]
BPFE116.7g (0.23mol), acrylic acid 33.1g (0.46mol), TPP0.60g, and PGMEA161.0 were charged into a 1L four-necked flask equipped with a carbonization condenser, and heated under 100 to 105°C. After stirring for 12 hr, a reaction product was obtained.

Then, BPDA33.8g (0.12mol) and THPA17.5g (0.12mol) were charged to the obtained reaction product, and the mixture was stirred for 6 hours under heating at 115 to 120°C, and the polymerizable unsaturated group-containing alkali-soluble resin solution ( A)-1 was obtained. The solid content concentration of the obtained resin solution was 56.5 wt%, the acid value (solid content conversion) was 102 mgKOH/g, and the Mw by GPC analysis was 3,600.

[Synthesis example 2]
BPFE 116.7g (0.23mol), acrylic acid 33.1g (0.46mol), TPP0.60g, and PGMEA161.0 were charged into a 1L four-necked flask equipped with a carbonization condenser and heated at 100 to 105°C. After stirring for 12 hr, a reaction product was obtained.

Next, BTDA37.1g (0.12mol) and THPA17.5g (0.12mol) were charged to the obtained reaction product, and the mixture was stirred for 6 hours under heating at 115 to 120°C, and a polymerizable unsaturated group-containing alkali-soluble resin solution ( A)-2 was obtained. The solid content concentration of the obtained resin solution was 56.6 wt%, the acid value (solid content conversion) was 102 mgKOH/g, and the Mw by GPC analysis was 3700.

[Comparative Synthesis Example 1]
Methacrylic acid 51.65 g (0.60 mol), methyl methacrylate 38.44 g (0.38 mol), benzyl methacrylate 38.77 g (0.22 mol), azobisisobutyronitrile 5.91 in a 1000 ml four-necked flask equipped with a nitrogen introduction tube and a reflux tube. g and 370 g of diethylene glycol dimethyl ether were charged, and the mixture was stirred at 80 to 85° C. for 8 hours under a nitrogen stream to perform polymerization. Furthermore, 39.23 g (0.28 mol) of glycidyl methacrylate, TPP1.44 g, and 0.055 g of 2,6-di-tert-butyl-p-cresol were charged into the flask, and the mixture was stirred at 80 to 85° C. for 16 hours, and the alkali-soluble resin solution was added. (A)-3 was obtained. The solid content concentration of the obtained resin solution was 32 mass %, the acid value (solid content conversion) was 110 mgKOH/g, and the Mw by GPC analysis was 18,100.

(Polymerizable unsaturated group-containing alkali-soluble resin)
(A)-1 component: Alkali-soluble resin solution obtained in Synthesis Example 1 above
(A)-2 component: Alkali-soluble resin solution obtained in Synthesis Example 2 above
(A)-3 component: Alkali-soluble resin solution obtained in Comparative Synthesis Example 1 above

(Photopolymerizable monomer)
(B): Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (Nippon Kayaku Co., Ltd., trade name DPHA)

(Photopolymerization initiator)
(C): Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-,1-(0-acetyloxime) (BASF Japan Ltd., product name Irgacure OXE02 )

(Light-shielding dispersion pigment)
(D)-1: Titanium black (manufactured by Mitsubishi Materials Corporation, product name 13M-C) concentrated 20.0% by mass, dispersant concentration 5.0% by mass PGMEA dispersion (solid content 25.0%, average secondary particle size of titanium black) (188 nm)
(D)-2: Black pigment (Lactam Black BASF Irgaphor S100CF) 15.0% by mass, polymer dispersant 4.5% by mass PGMEA dispersion (solid content 19.5%, average secondary particle size of black pigment 241 nm)
(D)-3: C.I. I. Pigment Orange 64 (manufactured by BASF) 7.0% by mass, C.I. I. Pigment Violet 23 (Clariant) 3.0% by mass, C.I. I. Pigment Blue 15:6 (manufactured by Clariant), 7.0% by mass, polymer dispersant concentration 4.0% by mass, sulfonated azo dispersion aid 2.0% by mass, benzyl methacrylate/methacrylic acid copolymer 2.0% by mass PGMEA dispersion liquid (Solid content 25.0%)
(D)-4: PGMEA dispersion liquid containing 20.0% by mass of carbon black and 5.0% by mass of polymer dispersant (solid content 25.0%, average secondary particle size of carbon black 162 nm)

(solvent)
(E)-1: PGMEA
(E)-2: 3-methoxy-3-methyl-1-butyl acetate

(Surfactant)
(H): BYK-330 (manufactured by BYK Chemie) PGMEA solution (solid content 1.0%)

The above-mentioned components were blended in the proportions shown in Table 1 to prepare the photosensitive resin compositions of Examples 1-6 and Comparative Examples 1-2. In addition, all the numerical values in Table 1 represent parts by mass. Further, (E)-1 in the column of the solvent is PGMEA (the same as (E)-1) in the unsaturated group-containing resin solution (polymerizable unsaturated group-containing alkali-soluble resin solution), and the light-shielding dispersion liquid. The amount does not contain PGMEA (same as (E)-1).

[Evaluation]
Using the photosensitive resin compositions for the light-shielding film of Example 1 , Reference Examples 1-5 and Comparative Examples 1-2, the following evaluations were performed. The results of these evaluations are shown in Table 2.

<Development characteristics>
Each of the photosensitive resin compositions obtained above was applied onto a glass substrate having a thickness of 1.2 mm using a spin coater so that the film thickness after heat curing treatment would be 3.0 μm, and the composition was applied at 90° C. for 1 hour. Prebaked for a minute. Then, a photomask was brought into close contact with the substrate, and a 500 W high-pressure mercury lamp was used to irradiate ultraviolet rays of 100 mJ/cm ² with an ultrahigh-pressure mercury lamp having an illuminance of 365 nm and an illuminance of 30 mW/cm ² .

Next, the exposed glass substrate was developed with a 0.05% aqueous potassium hydroxide solution at 24° C. and a pressure of 0.1 MPa for 60 seconds to remove the unexposed portion of the coating film. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition.
The fine line formation of the obtained cured film pattern was confirmed by an optical microscope and evaluated in the following three stages. The results are shown in Table 2.
◯: A pattern with L/S of 10 μm/10 μm or more is formed without residue Δ: A pattern with L/S of 30 μm/30 μm or more is formed without residue X: L/S is less than 50 μm/50 μm Pattern is not formed, or pattern hem and residue are conspicuous

<Optical density>
Each of the photosensitive resin compositions obtained above was applied on a glass substrate having a thickness of 1.2 mm by a spin coater so that the film thickness after heat curing treatment would be 1.1 μm, and the composition was applied at 90° C. for 1 hour. Prebaked for a minute. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition. Next, the optical density of the obtained cured film was measured using a Macbeth transmission densitometer and evaluated by the optical density per unit film thickness.

<Volume resistivity>
Each of the photosensitive resin compositions obtained above had a film thickness of 3.5 μm after heat curing using a spin coater on a portion excluding electrodes on a 1.2 mm-thick Cr-deposited glass substrate. And was prebaked at 90° C. for 1 minute. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition. Then, an aluminum electrode was formed on the cured film to prepare a substrate for measuring volume resistivity. Next, the volume resistivity at an applied voltage of 1 V to 10 V was measured using an electrometer (“6517A type” manufactured by Keithley). The measurement was performed under the condition that the voltage was held for 60 seconds at each applied voltage in 1 V steps, and the volume resistivity when 10 V was applied is shown in Table 2.

<Dielectric constant>
Each of the photosensitive resin compositions obtained above had a film thickness of 3.5 μm after heat curing using a spin coater on a portion excluding electrodes on a 1.2 mm-thick Cr-deposited glass substrate. And was prebaked at 90° C. for 1 minute. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition. Then, an aluminum electrode was formed on the cured film to prepare a dielectric constant measurement substrate. Next, using an electrometer (manufactured by Keithley, "6517A type"), the electric capacity at a frequency of 1 Hz to 100000 Hz was measured, and the dielectric constant was calculated from the electric capacity. The calculated dielectric constant is shown in Table 2.

<Spacer halftone (HT) characteristics>
Each of the photosensitive resin compositions obtained above was applied onto a glass substrate having a thickness of 1.2 mm using a spin coater so that the film thickness after heat curing treatment would be 3.0 μm, and the composition was applied at 90° C. for 1 hour. Prebaked for a minute. Then, is adhered a photomask having a dot pattern, it is irradiated with ultraviolet light of 5 mJ / cm ² or 100 mJ / cm ² by an ultra-high pressure mercury lamp of the illuminance 30 mW / cm ² in the wavelength 365nm using a 500W high-pressure mercury lamp, a photosensitive The part was photocured.
Next, the exposed glass substrate was developed with a 0.05% aqueous potassium hydroxide solution at 24° C. and a pressure of 0.1 MPa for 60 seconds to remove the unexposed portion of the coating film. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition.

Halftone characteristics of the spacer, the exposure amount calculating a difference ([Delta] H) of the thickness of the spacer (H2) in 5 mJ / cm thickness of the light-shielding film in ² (H1) and 100 mJ / cm ^2, the following four stages evaluated. The results are shown in Table 2.
◯: ΔH is 1.0 μm to 2.0 μm Δ: ΔH is 0.1 μm to 2.9 μm ×: ΔH is less than 0.1 μm or larger than 2.9 μm

<Spacer compressibility, elastic recovery rate, fracture strength>
Each of the photosensitive resin compositions obtained above was applied onto a glass substrate having a thickness of 1.2 mm using a spin coater so that the film thickness after heat curing treatment would be 3.0 μm, and the composition was applied at 90° C. for 1 hour. Prebaked for a minute. After that, a photomask having a dot pattern is brought into close contact, and an ultraviolet ray of 100 mJ/cm ² is irradiated with an ultrahigh pressure mercury lamp of illuminance 30 mW/cm ² having a wavelength of 365 nm using a 500 W high pressure mercury lamp to perform photo-curing reaction on the exposed portion. I went.

Next, the exposed glass substrate was developed with a 0.05% aqueous potassium hydroxide solution at 24° C. and a pressure of 0.1 MPa for 60 seconds to remove the unexposed portion of the coating film. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition.
The spacer characteristics of the obtained cured film pattern were evaluated using an ultra-micro hardness meter (Fisher Instruments HM2000Xyp, manufactured by Fisher Instruments). A 100 μm square flat indenter was pushed at a loading speed of 5.0 mN/sec, a load of up to 50 mN was applied, and then a unloading speed of 5.0 mN/sec was used to create a displacement amount curve.
The compressibility was calculated from the following formula with the displacement amount under load of 50 mN under load as L1.
Compressibility (%) = L1/spacer height x 100

The elastic recovery rate was calculated from the following formula, with the displacement amount under load of 50 mN under load being L1 and the displacement amount during unloading being L2.
Elastic recovery rate (%)=(L1-L2)/L1×100

The breaking strength was evaluated using an ultra-micro hardness meter (Fischer Scope HM2000Xyp, manufactured by Fisher Instruments). A 100 μm square flat indenter was pushed in at a loading speed of 5.0 mN/sec, a load of up to 300 mN was applied, and the load when the spacer broke was measured and evaluated according to the following four stages. The results are shown in Table 2.
◯: Breaking strength is 300 mN or more Δ: Breaking strength is 200 mN or less ×: Breaking strength is 100 mN or less

<Spacer shape>
Each of the photosensitive resin compositions obtained above was applied onto a glass substrate having a thickness of 1.2 mm using a spin coater so that the film thickness after heat curing treatment would be 3.0 μm, and the composition was applied at 90° C. for 1 hour. Prebaked for a minute. After that, a photomask having a dot pattern is brought into close contact, and an ultraviolet ray of 100 mJ/cm ² is irradiated with an ultrahigh pressure mercury lamp of illuminance 30 mW/cm ² having a wavelength of 365 nm using a 500 W high pressure mercury lamp to perform a photocuring reaction on the photosensitive portion. I went.

Next, this exposed glass substrate was developed for 60 seconds at 24° C. and a pressure of 0.1 MPa using a 0.05% aqueous potassium hydroxide solution to remove the unexposed portion of the coating film. After that, a heat curing treatment was performed at 230° C. for 30 minutes using a hot air dryer to obtain a cured film of the photosensitive resin composition.
The shape of the spacer was evaluated by the internal angle (taper angle) of the end of the spacer using a scanning electron microscope. When the taper angle was 70° or more and 90° or less, it was marked with ⊚, when it was 50° or more and less than 70°, it was marked with Δ, when it was 50° or less, it was marked with Δ, and when it was 90° or more, it was marked.

From the results of Example 1 , Reference Examples 1 to 5 and Comparative Examples 1 and 2, by using titanium black as the light shielding material (D), the light shielding property, the dielectric constant, the elastic recovery rate and the like while maintaining the volume resistivity were maintained. It can be seen that the spacer characteristics can be improved. In particular, by using titanium black and a black organic pigment or a mixed color organic pigment in combination, the defects of each light shielding material can be complemented without deteriorating the spacer properties such as elastic recovery rate, and the light shielding property, volume resistivity, and dielectric constant of It turns out that it is effective for compatibility.

Claims (14)

The following (A) to (E) components,
(A) a tetracarboxylic acid or an acid dianhydride thereof, and (b) a dicarboxylic acid, or a reaction product of a reaction product of an epoxy compound represented by the general formula (I) and an unsaturated group-containing monocarboxylic acid. Tricarboxylic acid or acid anhydride thereof, a polymerizable unsaturated group-containing alkali-soluble resin obtained by reacting,
(In the general formula (I), R ₁ , R ₂ , R ₃ and R ₄ independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom or a phenyl group, and X is fluorene-9, It represents a 9-diyl group, and the average value of m is in the range of 0 to 10.)
(B) a photopolymerizable monomer having at least one ethylenically unsaturated bond,
(C) a photopolymerization initiator,
(D) shielding component comprising a lactam black click, and the solvent (E),
A photosensitive resin composition for a light-shielding film having a spacer function, which is contained as an essential component. Characterized in that before the average secondary particle diameter of Kira Kutamubura' click is 20 to 500 nm, the photosensitive resin composition of claim 1. 5 to 400 parts by mass of the component (B) per 100 parts by mass of the component (A),
The component (C) is contained in an amount of 0.1 to 30 parts by mass based on 100 parts by mass of the total amount of the components (A) and (B), and the component (E) is included, which is the solid content after photocuring. When the components to be excluded are solid contents,
5 to 80 mass% of the component (D) in the total solid content,
The photosensitive resin composition according to claim 1 or 2 , wherein the photosensitive resin composition comprises each of them. A light-shielding film having an optical density OD of 0.5/μm or more and 3/μm or less, having a volume resistivity of 1×10 ⁹ Ω·cm or more and a relative dielectric constant of 2 to 10 when a voltage of 10 V is applied. characterized in that capable of forming a light shielding film, the photosensitive resin composition according to any one of claims 1-3. Load by microhardness tester - in unloading test, characterized in that capable of forming a light shielding film which satisfies at least one of the following (i) ~ (iii), according to any one of claims 1-4 Photosensitive resin composition.
(I) Breaking strength is 200 mN or more (ii) Elastic recovery is 30% or more (iii) Compressibility is 40% or less Characterized by being formed by curing the photosensitive resin composition according to any one of claims 1 to 5 the light-shielding film having a spacer function. A liquid crystal display device comprising the light shielding film according to claim 6 as a black column spacer (BCS). The liquid crystal display device according to claim 7 , further comprising a thin film transistor (TFT). (D) After preparing a dispersion in which a light-shielding component is dispersed in (E) a solvent, (A) an alkali-soluble resin, (B) a photopolymerizable polymer having at least one ethylenically unsaturated bond A method for producing a photosensitive resin composition for a light-shielding film having a spacer function, which further comprises adding and mixing a monomer, (C) a photopolymerization initiator, and (E) a solvent,
The (A) alkali-soluble resin is a reaction product of an epoxy compound having two glycidyl ether groups derived from bisphenols with an unsaturated group-containing monocarboxylic acid, and (a) a tetracarboxylic acid or an acid thereof. A dianhydride, and (b) an alkali-soluble resin obtained by reacting a dicarboxylic acid or a tricarboxylic acid or an acid anhydride thereof,
(D) the light blocking component is a lactam black click method. In the dispersion, wherein the average secondary particle diameter of the lactam black click is 20 to 500 nm, The method of claim 9. The photosensitive resin composition according to any one of claims 1 to 5 applied to a substrate, curing the photosensitive resin composition by light irradiation method of manufacturing a light shielding film formed on the substrate. The method for producing a light-shielding film according to claim 11 , wherein a film thickness H1 for making the optical density of the light-shielding film 0.5/μm or more and less than 3/μm, and a film thickness H2 of the light-shielding film having a spacer function. Regarding H2, the method for producing a light-shielding film is characterized in that when H2 is 2 to 7 μm, the light-shielding film having a film thickness H1 and a film thickness H2 in which ΔH=H2-H1 is 0.1 to 2.9 is formed at the same time. A method for manufacturing a liquid crystal display device, wherein the light-shielding film manufactured by the method according to claim 12 is used as a black column spacer. The manufacturing method according to claim 13 , wherein the liquid crystal display device includes a thin film transistor (TFT).