Photosensitive composition, color filter substrate, fingerprint sensor, and display device

Abstract

The present invention provides a photosensitive composition that prevents deformation of the pattern due to excessive flow during firing of the photosensitive composition layer, suppresses the development pattern of the photosensitive composition layer from becoming undercut, and reduces the generation of residue. [Solution] A photosensitive composition containing an alkali-soluble resin, a radical polymerizable compound, and a photopolymerization initiator, wherein the photosensitive composition contains a bifunctional radical polymerizable compound having a double bond equivalent of 200 to 500, and the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components satisfies 320 to 490.

Description

[Technical Field]

[0001] The present invention relates to a photosensitive composition, a color filter substrate, a fingerprint sensor, and a display device, and more particularly to a photosensitive composition for forming pixels on a color filter substrate or a fingerprint sensor, a color filter substrate having pixels made of a photocured product of the photosensitive composition, a fingerprint sensor having a photocured product of the photosensitive composition, and a display device having the color filter substrate or the fingerprint sensor. [Background technology]

[0002] A photosensitive composition layer is formed by coating a photosensitive composition onto a substrate, exposing the resulting coating to a desired pattern, and developing the exposed coating. Generally, these layers are patterned into stripe or mesh shapes. In the exposure process, exposure is performed from above the photosensitive composition layer, so the amount of exposure is greater at the top of the layer and decreases towards the bottom. Therefore, the cross-sectional shape of the photosensitive composition layer obtained after exposure and development tends to be an undercut shape, where the top surface of the photosensitive composition layer is wide and the bottom on the substrate side is narrow.

[0003] If this undercut shape remains, stress due to the curing shrinkage of the photosensitive composition layer may occur, and as a result, the photosensitive composition layer may peel off from the substrate. In order to avoid this, a technique for suppressing the generation of the undercut shape is disclosed in Patent Document 1. That is, Patent Document 1 discloses a photosensitive resin composition containing, as components, (A) a binder resin, (B) a polymerizable monomer, (C) a photopolymerization initiator, and (D) inorganic powder, wherein the (A) binder resin has at least an alicyclic skeleton having 6 or more carbon atoms and a carboxyl group, and is a (meth)acrylic resin having a molecular weight of 10,000 to 30,000, and the average double bond equivalent in the organic component composed of the total of the (A) binder resin and the (B) polymerizable monomer is 500 to 1,000 g / mol. By adjusting the firing temperature conditions, the developed pattern is softened, and during firing, the cross-sectional shape of the developed pattern self-formingly transforms into a trapezoidal shape, a hill shape, or a kamaboko shape that narrows from the substrate adhesion part toward the upper surface, and is cured in that shape. When the length of the part adhering to the substrate (substrate adhesion side length or bottom length) is A and the length of the upper part of the developed pattern (pattern upper part length) is B, it is also disclosed that A < B.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the invention described in Patent Document 1, excessive flow occurs during the self-forming firing of the developed pattern, the cross-sectional shape of the developed pattern is unstable and easily deformed, and when it is cured in that shape, a part thereof may be softened again and the shape may be deformed. As a result, there is a problem that the numerical values of the length of the part adhering to the substrate (substrate adhesion side length or bottom length) A and the length of the upper part of the developed pattern (pattern upper part length) B are not stabilized. [Means for solving the problem]

[0006] The photosensitive composition of the present invention has the following configuration in order to solve the above problems. That is, A photosensitive composition containing an alkali-soluble resin, a radical polymerizable compound, and a photopolymerization initiator, wherein the photosensitive composition contains a bifunctional radical polymerizable compound having a double bond equivalent of 200 to 500, and the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components satisfies 320 to 490.

[0007] The color filter substrate of the present invention has the following configuration: The color filter substrate has pixels made of a photocured product of the aforementioned photosensitive composition.

[0008] The fingerprint sensor of the present invention has the following configuration: The fingerprint sensor has a photocured product of the aforementioned photosensitive composition.

[0009] The display device of the present invention has the following configuration: The display device having the color filter substrate or the fingerprint sensor.

[0010] The photosensitive composition of the present invention preferably contains the difunctional radical polymerizable compound of general formula (1).

[0011] [ka]

[0012] However, R 1 ~R 8 Each of these is independently either a hydrogen atom, an acrylic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.

[0013] In the photosensitive composition of the present invention, it is preferable that the bifunctional radical polymerizable compound contains the general formula (2).

[0014]

Chemical formula

[0015] However, m and n are each 1 or more, and m + n is 3 to 6.

[0016] In the photosensitive composition of the present invention, it is preferable that the alkali-soluble resin has a tricyclodecanyl skeleton.

[0017] In the photosensitive composition of the present invention, it is preferable that the mass ratio of the unit having a tricyclodecanyl skeleton contained in the alkali-soluble resin is 2% by mass or more and 30% by mass or less in the alkali-soluble resin.

[0018] In the photosensitive composition of the present invention, it is preferable that the content of the alkali-soluble resin is 10% by mass or more and 30% by mass or less in the solid content.

[0019] The photosensitive composition of the present invention contains a green coloring material having a metal phthalocyanine skeleton, and preferably has a light transmittance of 1% or more and 5% or less at 350 to 380 nm.

Advantages of the Invention

[0020] In the photosensitive composition of the present invention, the radical polymerizable compound is a bifunctional radical polymerizable compound, and its double bond equivalent is 200 or more and 500 or less. Thereby, it is possible to prevent deformation of the pattern due to excessive flow when baking the photosensitive composition layer, suppress the development pattern of the photosensitive composition layer from becoming an undercut shape, and reduce the generation of residues.

[0021] Furthermore, by having a ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solid content of the organic components, a development pattern of the photosensitive composition layer with a cross-sectional shape that minimizes undercuts can be stably formed, thereby reducing the generation of residue. [Modes for carrying out the invention]

[0022] The photosensitive composition of the present invention will be described in detail below.

[0023] The photosensitive composition of the present invention is a photosensitive composition containing an alkali-soluble resin, a radical polymerizable compound, and a photopolymerization initiator, wherein the photosensitive composition contains a bifunctional radical polymerizable compound having a double bond equivalent of 200 to 500, and the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components satisfies 320 to 490.

[0024] The photosensitive composition of the present invention contains a radical polymerizable compound. A radical polymerizable compound, as used herein, refers to a compound that reacts by radical polymerization and has a weight-average molecular weight of 1,500 or less. The radical polymerizable compound is preferably a compound having an unsaturated hydrocarbon group. Examples of unsaturated hydrocarbon groups include (meth)acryloyl groups, vinyl groups, and maleimide groups. Two or more of these groups may be present.

[0025] Examples of radical polymerizable compounds include dipentaerythritol penta(meth)acrylate, tetratrimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, penta(meth)acryloyloxydipentaerythritol monosuccinate, dipentaerythritol hexa(meth)acrylate, and other ethylene oxide modified or propylene oxide modified compounds, styrene derivatives, polyfunctional maleimide compounds, poly(meth)acrylate carbamates, 1,6-hexanediol(meth)acrylic acid adipic acid, propylene oxide(meth)acrylic acid phthalate anhydride, diethylene glycol(meth)acrylic acid trimellitic acid, rosin-modified epoxy di(meth)acrylate, alkyd-modified(meth)acrylate oligomers, trimethylolpropane tri(meth)acrylate, triacrylic formal, and others. Two or more of these may be included. From the viewpoint of the stability of the coating after application, it is preferable to use pentaerythritol triacrylate as the radical polymerizable compound.

[0026] Furthermore, the photosensitive composition of the present invention contains a bifunctional radical polymerizable compound having a double bond equivalent of 200 or more and 500 or less. The double bond equivalent referred to here is the weight per mole of radical polymerizable double bond groups, and the unit is g / mol. The double bond equivalent can be calculated from the iodine value, and the number of double bond groups in the radical polymerizable compound can be determined from the value of the double bond equivalent. By having a double bond equivalent of 200 or more in the bifunctional radical polymerizable compound, deformation of the pattern due to excessive flow when firing the photosensitive composition layer can be prevented, and the development pattern of the photosensitive composition layer can be suppressed from becoming an undercut shape. In addition, by having a double bond equivalent of 500 or less in the bifunctional radical polymerizable compound, solubility in alkaline developer is improved and the generation of residue is reduced. From the viewpoint of improving solubility and adhesion strength to the substrate, the double bond equivalent of the bifunctional radical polymerizable compound is preferably 450 or less, and more preferably 400 or less.

[0027] Furthermore, from the viewpoint of suppressing delamination due to curing shrinkage of the radical polymerizable compound, the double bond equivalent of the difunctional radical polymerizable compound is preferably 250 or more, and more preferably 300 or more.

[0028] Difunctional radical polymerizable compounds are compounds that have two reactive groups that react through radical polymerization. Radical polymerization is a type of polymerization that undergoes a chain reaction consisting of an initiation reaction, a growth reaction, a chain transfer reaction, and a termination reaction as elementary reactions, while simultaneously undergoing a reaction that hinders polymer chain growth. The reactive groups are highly reactive active groups that possess unpaired electrons.

[0029] Examples of difunctional radical polymerizable compounds include alkyl group-containing difunctional (meth)acrylates such as tripropylene glycol di(meth)acrylate and 1,6-hexanediol di(meth)acrylate, decanyl skeleton-containing difunctional (meth)acrylates such as tricyclodecanol methacrylate, and aromatic group-containing difunctional (meth)acrylates such as ethoxylated bisphenol A dimethacrylate.

[0030] In particular, from the viewpoint of minimizing deformation of the cross-sectional shape due to softening after curing and suppressing the development pattern from becoming an undercut shape, preferred bifunctional radical polymerizable compounds include aromatic group-containing bifunctional (meth)acrylates, for example, the compound of the following formula (1). Note that in the following formula (1), R 1 ~R 8 Each of these is independently either a hydrogen atom, an acrylic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.

[0031] [ka]

[0032] As a bifunctional radical polymerizable compound, the compound of the following formula (2) is more preferred. In the following formula (2), m and n are each 1 or greater, and m+n is 3 to 6.

[0033] [ka]

[0034] Furthermore, the radical polymerizable compound may include a radical polymerizable compound containing a hydroxyl group. The hydroxyl group has a high affinity for alkaline developer, and the unexposed portion of the radical polymerizable compound containing it has high solubility in alkaline developer. This allows the alkaline developer to penetrate even the finest details of the photosensitive composition layer during the development process, enabling firing at low temperatures and reducing film residue in the photosensitive composition layer.

[0035] Examples of radical polymerizable compounds having such hydroxyl groups include pentaerythritol triacrylate. A particularly preferred radical polymerizable compound is obtained by mixing the aromatic group-containing difunctional (meth)acrylate and pentaerythritol triacrylate in a weight ratio of 1.0:0.1 to 1.0:3.2. Note that a difunctional radical polymerizable compound in which a hydroxyl group has been introduced into the molecule may be used alone as the difunctional radical polymerizable compound.

[0036] By using these materials and weight ratios, the photosensitive composition can be easily diluted with organic solvents such as PGMEA, and the photosensitive composition diluted with the organic solvent has excellent dispersibility. Furthermore, the resulting photosensitive composition layer can be prevented from forming an undercut shape, and a photosensitive composition layer with minimal deformation of the cross-sectional shape due to softening after curing can be formed.

[0037] The content of the radical polymerizable compound is preferably 25% by mass or more of the solid content of the photosensitive composition, and more preferably 30% by mass or more of the solid content. By including 25% by mass or more of the radical polymerizable compound, the alkaline developer can penetrate even into fine details, improving the solubility of the binder resin. On the other hand, from the viewpoint of suppressing deformation of the pattern due to flow during firing when forming the photosensitive composition layer, the content of the radical polymerizable compound is preferably 90% by mass or less of the solid content of the photosensitive composition, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0038] The photosensitive composition of the present invention contains an alkali-soluble resin. Examples of alkali-soluble resins include acrylic resins, cardo resins, epoxy resins, polyimide resins, urethane resins, polyvinyl alcohol resins, melamine resins, polyamide resins, polyamide-imide resins, polyester resins, and polyolefin resins. Two or more of these may be included.

[0039] In particular, acrylic resins are preferred due to their ease of solubility in alkaline developers and organic solvents, transparency, and stability. Furthermore, acrylic resins having copolymers composed of unsaturated carboxylic acids are preferred because they have high water resistance and compatibility with other organic components. Examples of such acrylic resins include unsaturated carboxylic acid aminoalkyl esters, unsaturated carboxylic acid glycidyl esters, and vinyl carboxylic acid esters.

[0040] Examples of unsaturated carboxylic acids include monocarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, or vinylacetic acid, or dicarboxylic acids such as itaconic acid, maleic acid, or fumaric acid, or their acid anhydrides. Unsaturated carboxylic acids derived from acrylic acid or methacrylic acid are particularly preferred.

[0041] Furthermore, the alkali-soluble resin is more preferably an acrylic resin having a tricyclodecanyl skeleton composed of monomer components such as tricyclodecanyl (meth)acrylate, tricyclodecanyl dimethylol di(meth)acrylate, and pentacyclopentadecanedimethanol di(meth)acrylate. Photosensitive compositions containing an alkali-soluble resin having a tricyclodecanyl skeleton exhibit high transparency and etching resistance of the developed pattern of the photosensitive composition layer after photocuring, enabling high-precision etching. In addition, they have excellent adhesion to the substrate and shape retention, making them less prone to undercuts.

[0042] Examples of functional groups having a tricyclodecanyl skeleton include 2-methyl-2-tricyclodecanyl group, 2-ethyl-2-tricyclodecanyl group, 8-hydroxy-3-tricyclodecanyl group, 8-oxo-3-tricyclodecanyl group, 8-cyano-3-tricyclodecanyl group, 8-[2-hydroxy-2,2-di(trifluoromethyl)ethyl]-3-tricyclodecanyl group, and 8-ethyl-8-tricyclodecanyl group.

[0043] From the viewpoint of stability of the photosensitive resin layer after coating, the mass ratio of units having a tricyclodecanyl skeleton in the alkali-soluble resin is preferably 2% to 30% by mass. Furthermore, from the viewpoint of adhesion to the substrate and shape retention, the mass ratio of units having a tricyclodecanyl skeleton is more preferably 5% to 15% by mass.

[0044] The mass ratio of units having a tricyclodecanyl skeleton can be calculated by the following method. First, each component contained in the photosensitive composition of the present invention is isolated and purified by methods such as preparative GPC, preparative HPLC, and column purification. Next, structural analysis is performed. 1 H-NMR, 13 Each component is identified using 1C-NMR, 2D NMR such as HMBC and HMQC, etc. Based on the structural analysis results, the mass ratio of the tricyclodecanyl skeleton to the total alkali-soluble resin is calculated.

[0045] The weight-average molecular weight of the alkali-soluble resin is preferably 3,000 or more, and more preferably 9,000 or more, from the viewpoint of the strength of the photosensitive composition layer. On the other hand, from the viewpoint of the stability of the photosensitive composition, the weight-average molecular weight of the alkali-soluble resin is preferably 200,000 or less, and more preferably 100,000 or less. By setting the weight-average molecular weight of the alkali-soluble resin to 100,000 or less, it is possible to prevent the occurrence of edge curls due to undercuts in the development pattern of the photosensitive composition layer after photocuring. The weight-average molecular weight can be expressed as a standard polystyrene equivalent value measured by gel permeation glometry.

[0046] The alkali-soluble resin content is preferably 10% by mass or more, and more preferably 20% by mass or more, in the solid content, from the viewpoint of patternability when forming the photosensitive composition layer, prevention of undercuts, and appropriate taper angle. On the other hand, from the viewpoint of shape retention and appropriate taper angle, the alkali-soluble resin content is preferably 30% by mass or less, and more preferably 25% by mass or less, in the solid content. The acid value of the alkali-soluble resin is preferably 20 to 200 (mgKOH / g), and more preferably 30 to 150 (mgKOH / g), in order to obtain appropriate alkali developability. Here, appropriate taper angle refers to a taper angle of 60 degrees or more and 87 degrees or less of the pattern. From the viewpoint of pattern processability, the taper angle is preferably 60 degrees or more, more preferably 65 degrees or more, and even more preferably 70 degrees or more. Furthermore, from the viewpoint of preventing color mixing, the taper angle is preferably 87 degrees or less, and more preferably 85 degrees or less.

[0047] The photosensitive composition of the present invention contains a photopolymerization initiator. A photopolymerization initiator is a compound that decomposes and / or reacts with light (including ultraviolet light or electron beams) to generate radicals. The photopolymerization initiator triggers the reaction of unsaturated double bonds present in the alkali-soluble resin and radical-polymerizable compound contained in the photosensitive composition, and prevents adverse effects from unreacted double bonds.

[0048] Examples of photopolymerization initiators include oxime ester compounds, benzophenone compounds, acetophenone compounds, oxantone compounds, anthraquinone compounds, imidazole compounds, benzothiazole compounds, benzoxazole compounds, carbazole compounds, triazine compounds, phosphorus compounds, and titanocene compounds.

[0049] More specifically, examples of oxime ester compounds include 1,2-octanedione,1-[4-(phenylthio)phenyl]-,2-(O-benzoyl oxime), ethanoone,1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyl oxime), ethanoone,1-[9-ethyl-6-(2-methyl-4-tetrahydrofuranylmethoxybenzoyl)-9H-carbazole-3-yl]-,1-(O-acetyl oxime), ethanoone, Examples include 1-[9-ethyl-6-{2-methyl-4-(2,2-dimethyl-1,3-dioxolanyl)methoxybenzoyl}-9H-carbazole-3-yl]-,1-(O-acetyloxime),1,2-octanedione,1-[4-(phenylthio)-2-(O-benzoyloxime)], “ADEKA ARCULES” (trademark registered) N-1919, NCI-930 (manufactured by ADEKA Corporation), and “IRGACURE” (trademark registered) OXE01, OXE02 (manufactured by BASF Japan Ltd.).

[0050] Examples of benzophenone compounds include benzophenone, N,N'-tetraethyl-4,4'-diaminobenzophenone, and 4-methoxy-4'-dimethylaminobenzophenone. Examples of acetophenone compounds include 2,2-diethoxyacetophenone, benzoin, benzoin methyl ether, benzoin isobutyl ether, benzyldimethyl ketal, α-hydroxyisobutylphenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propane, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, and “IRGACURE” (trademark registered) 369, 379, 907 (manufactured by BASF Japan Ltd.).

[0051] Examples of anthraquinone compounds include t-butylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone, 3-chlor-2-methylanthraquinone, 2-ethylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthaquinone, 1,2-benzoanthraquinone, 1,4-dimethylanthraquinone, and 2-phenylanthraquinone.

[0052] Examples of imidazole compounds include 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer. Examples of azole compounds include 2-mercaptobenzothiazole. Examples of benzoxazole compounds include 2-mercaptobenzoxazole. Examples of triazine compounds include 4-(p-methoxyphenyl)-2,6-di-(trichloromethyl)-s-triazine. Two or more of these may be included.

[0053] From the viewpoint of sensitivity, patternability, and processability, the content of the photopolymerization initiator is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 5% by mass or more, in the solid content of the photosensitive composition. On the other hand, from the viewpoint of sensitivity, patternability, processability, and heat resistance, the content of the photopolymerization initiator is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, in the solid content of the photosensitive composition.

[0054] The photosensitive composition of the present invention satisfies the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components of the photosensitive composition, which is 320 or more and 490 or less. However, if the photosensitive composition contains a colorant as described later, the photosensitive composition of the present invention satisfies the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components excluding the colorant of the photosensitive composition, which is 320 or more and 490 or less. Here, "solids" refers to all components contained in the photosensitive composition, excluding organic solvents.

[0055] By having a ratio T / M of the number of moles M of radical polymerizable groups to the total amount T of solids of organic components excluding the colorant in the photosensitive composition, or, if the photosensitive composition contains a colorant, the total amount T of solids of organic components excluding the colorant in the photosensitive composition, then 320 to 490, softening during the curing of the development pattern of the photosensitive composition layer can be suppressed, and deformation of the cross-sectional shape can be reduced. As a result, a pattern without undercuts and with a taper angle of 60 degrees or more can be stably formed. From the viewpoint of preventing undercuts, the ratio T / M of the number of moles M of radical polymerizable groups to the total amount T of solids of organic components excluding the colorant in the photosensitive composition, or, if the photosensitive composition contains a colorant, the total amount T of solids of organic components excluding the colorant in the photosensitive composition, is preferably 320 or more, and more preferably 340 or more. Furthermore, from the viewpoint of reducing residue, the ratio T / M of the number of moles M of radical polymerizable groups to the total amount T of solids of organic components excluding the colorant in the photosensitive composition, or, if the photosensitive composition contains a colorant, the total amount T of solids of organic components excluding the colorant in the photosensitive composition, is preferably 490 or less, and more preferably 450 or less. From the viewpoint of pattern processability, the taper angle is preferably 60 degrees or more, more preferably 65 degrees or more, and even more preferably 70 degrees or more. Furthermore, from the viewpoint of preventing color mixing, the taper angle is preferably 87 degrees or less, and more preferably 85 degrees or less.

[0056] The total amount T of solids of the organic components of a photosensitive composition, or, if the photosensitive composition contains a colorant, the total amount T of solids of the organic components excluding the colorant, and the number of moles M of radical polymerizable groups contained in the solids, can be measured and calculated, for example, by the following method. First, the photosensitive composition is weighed. Then, each component contained in the photosensitive composition is isolated and purified by methods such as preparative GPC, preparative HPLC, or column purification, and the weight of each component is measured.

[0057] Next, regarding the structural analysis of each component, 1 H-NMR, 13The organic components are identified and quantified using methods such as 1C-NMR, HMBC, and HMQC. From the structural analysis results, the weight ratio of the solid content to the entire photosensitive composition is calculated to determine the total amount T of solid content of the organic components of the photosensitive composition, or, if the photosensitive composition contains a colorant, the total amount T of solid content of the organic components excluding the colorant. The number of moles M of radical polymerizable groups is then calculated from the structure and weight of each component containing radical polymerizable groups to determine the number of moles M of radical polymerizable groups contained in the solid content.

[0058] The photosensitive composition of the present invention may contain a colorant. Examples of colorants include organic pigments, inorganic pigments, and dyes, and may contain two or more of these. Among these, organic pigments and dyes are preferred from the viewpoint of further improving transmittance.

[0059] Examples of green colorants include organic pigments, inorganic pigments, and dyes. For example, CI Pigment Green (hereinafter referred to as "PG") PG1, PG2, PG4, PG7, PG8, PG10, PG13, PG14, PG15, PG17, PG18, PG19, PG26, PG36, PG38, PG39, PG45, PG48, PG50, PG51, PG54, PG55, PG58, and PG59 (all numbers are color index numbers). Two or more of these may be included.

[0060] Among these, the photosensitive composition of the present invention preferably contains a green colorant having a metal phthalocyanine skeleton, such as PG58 or PG59, from the viewpoint of good color density and brightness. Since the peak of parallel light transmittance of PG58 is 550 nm and the peak of parallel light transmittance of PG59 is 520 nm, if a green colorant is made by mixing PG58 and PG59 in a weight ratio of 1:2 to 1:5, the peak wavelength of the parallel light transmittance of the photosensitive composition layer can be made close to the ideal peak wavelength of green pixels, which is 530 nm. Furthermore, the photosensitive composition of the present invention is particularly preferred when the light transmittance in the 350 to 380 nm range is 1% or more and 5% or less, because the development pattern of the photosensitive composition layer after photocuring is less likely to be an undercut shape.

[0061] Examples of red pigments include CI Pigment Red (hereinafter referred to as "PR") 9, PR48, PR97, PR122, PR123, PR144, PR149, PR166, PR168, PR177, PR179, PR180, PR192, PR209, PR215, PR216, PR217, PR220, PR223, PR224, PR226, PR227, PR228, PR240, PR254, and diketopyrrolopyrrole pigments having bromine groups.

[0062] From the viewpoint of pixel brightness characteristics, PR254, PR177, and diketopyrrolopyrrole colorants having bromine groups are preferred, and from the viewpoint of brightness, vividness, and prevention of color mixing, it is preferable to use diketopyrrolopyrrole colorants having bromine groups.

[0063] Examples of yellow colorants include organic pigments, inorganic pigments, and dyes. For example, CI Pigment Yellow (hereinafter referred to as "PY") 12, PY13, PY17, PY20, PY24, PY83, PY86, PY93, PY95, PY109, PY110, PY117, PY125, PY129, PY137, PY138, PY139, PY147, PY148, PY150, PY153, PY154, PY166, PY168, and PY185 (all numbers are color index numbers). Two or more of these may be included.

[0064] Among these, PY129, PY138, PY139, PY150, and PY185 are preferred from the viewpoint of color purity, parallel light transmittance, and contrast, with PY150 and PY185 being more preferred. PY150 and PY185 have a greater suppression effect on the parallel light transmittance of light with wavelengths of 450-500 nm than other yellow colorants, and therefore also have the effect of improving the color purity of the green spectrum.

[0065] Examples of blue pigments include CI Pigment Blue (hereinafter referred to as "PB") 15, PB15:3, PB15:4, PB15:6, PB21, PB22, PB60, and PB64. Examples of purple pigments include CI Pigment Violet (hereinafter referred to as "PV") 19, PV23, PV29, PV30, PV32, PV37, PV40, and PV50 (all numbers above are color index numbers).

[0066] Examples of orange colorants include CI pigment orange (hereinafter referred to as "PO") 13, PO31, PO36, PO38, PO40, PO42, PO43, PO51, PO55, PO59, PO61, PO64, PO65, and PO71. Examples of dyes include oil-soluble dyes, acid dyes, direct dyes, basic dyes, and acid mordant dyes. The above dyes may also be lake-formed or used as salt compounds formed by combining dyes with nitrogen-containing compounds.

[0067] Examples of red, green, blue, purple, or yellow dyes include direct dyes, acid dyes, and basic dyes. Specific examples of these dyes include azo dyes, benzoquinone dyes, naphthoquinone dyes, anthraquinone dyes, xanthene dyes, cyanine dyes, squarylium dyes, croconium dyes, merocyanine dyes, stilbene dyes, diarylmethane dyes, triarylmethane dyes, fluorane dyes, spiropyran dyes, phthalocyanine dyes, indigo dyes, fulgide dyes, nickel complex dyes, and azulene dyes.

[0068] The dye may be dissolved in the photosensitive composition or dispersed as particles. To enhance resistance to heat, light, acid, alkali, or organic solvents, salt compounds consisting of organic acids such as organic sulfonic acids or organic carboxylic acids, or perchloric acid are preferred as basic dyes, and salt compounds consisting of naphthalene sulfonic acids such as tobias acid or perchloric acid are more preferred. Similarly, to enhance resistance to heat, light, acid, alkali, or organic solvents, salt compounds consisting of quaternary ammonium salts, primary to tertiary amines, or sulfonamides are preferred as acid dyes and direct dyes.

[0069] The type and weight of colorants in a photosensitive composition can be identified and quantified by laser Raman spectroscopy or mass spectrometry using a MALDI mass spectrometer or time-of-flight secondary ion mass spectrometer. From the weight of the obtained colorants and the weight of other non-volatile components, the percentage of colorants in the solid content of the photosensitive composition (mass%) can be calculated.

[0070] The photosensitive composition of the present invention may contain an organic solvent. The organic solvent can be adjusted to a viscosity that facilitates application of the photosensitive composition, and after application, it is dispersed by air drying or heating at a temperature lower than that of firing, so only a very small amount remains in the photosensitive composition layer.

[0071] Examples of organic solvents include ethylene glycol monoalkyl ethers, diethylene glycol dialkyl ethers, ethylene glycol alkyl ether acetates, alkylene glycol alkyl ether acetates, aromatic hydrocarbons, ketones, alcohols, and esters. Preferably, alkylene glycol alkyl ether acetates, ketones, and esters are used, and more preferably, alkylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate are used.

[0072] The photosensitive composition of the present invention may further contain a chain transfer agent, a sensitizer, a polymer dispersant, an adhesion improver, a surfactant, a pigment dispersant, and the like. Examples of chain transfer agents include thioglycolic acid, thiomalic acid, thiosalicylic acid, various propionic acids, 3-mercaptobutyric acid, various nicotinic acids, various sulfonic acids, various mercapto compounds, disulfide compounds obtained by oxidizing the mercapto compounds, and various alkyl iodides. Two or more of these may be included.

[0073] Examples of sensitizers include thioxanthone-based sensitizers and aromatic or aliphatic tertiary amines. Specifically, examples include thioxanthone, 2-chlorothioxanthone, and 2,4-diethylthioxanthene-9-one ("KAYACURE"® DETX-S (Nippon Kayaku Co., Ltd.)). Two or more of these may be included. Examples of polymeric dispersants include “DISPERBYK” (registered trademark)-102, 103, 106, 108, 109, 110, 111, 112, 116, 130, 140, 142, 145, 161, 162, 163, 164, 166, 167, 168, 170, 171, 174, 180, 182, 2000, 2001, 2050, 2070, 2150, 6919, 21116 (all trade names, Big Chemie). Two or more of these may be used.

[0074] Examples of adhesion-improving agents include silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane. Two or more of these may be included.

[0075] Examples of surfactants include anionic surfactants such as ammonium lauryl sulfate and polyoxyethylene alkyl ether sulfate triethanolamine, cationic surfactants such as stearylamine acetate and lauryltrimethylammonium chloride, amphoteric surfactants such as lauryldimethylamine oxide, nonionic surfactants such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether and sorbitan monostearate, fluorine-based surfactants, and silicone-based surfactants. Two or more of these may be included.

[0076] Examples of pigment dispersants include alkylamine-modified pigment skeletons, carboxylic acid derivatives, sulfonic acid derivatives, and other pigment derivatives, which are effective as synergists for wetting pigments and stabilizing fine pigment particles. Two or more of these may be included. The inclusion of a dispersant can improve dispersion stability. Among these, sulfonic acid derivatives of organic pigments are more preferred, as they can further improve the dispersion stability of fine pigment particles.

[0077] The method for producing the photosensitive composition of the present invention is not particularly limited and may be carried out by a general method. For example, the photopolymerization initiator and organic solvent may be placed in a container such as a flask, stirred to dissolve, a colorant may be added if necessary, then the alkali-soluble resin and radical polymerizable compound may be added, additional organic solvents and other additives may be added if necessary, and the mixture may be stirred for a further 20 minutes to 3 hours to obtain the composition. The obtained photosensitive composition may be filtered. When this photosensitive composition is applied to a substrate, a pattern is formed by photolithography, and then fired, a photosensitive composition substrate is obtained in which a photosensitive composition layer with a non-undercut cross-section is formed.

[0078] As a method for manufacturing a photosensitive composition substrate in which a photosensitive composition layer is patterned, there is a method of applying the photosensitive composition of the present invention onto a substrate to form a photosensitive composition layer, placing a mask on the photosensitive composition layer, exposing it, developing it to form a pattern, and then firing it. Examples of the method of applying the photosensitive composition onto the substrate to form a photosensitive composition layer include methods such as spin coater, bar coater, blade coater, roll coater, die coater, inkjet printing, screen printing, dipping, spray spraying, etc.

[0079] As a method for patterning the photosensitive composition layer, there is a method of installing a photomask on the photosensitive composition layer, selectively exposing it with an exposure light source, and performing development processing with an alkaline developer. Examples of the exposure light source include ultraviolet rays such as i-line, h-line, g-line, etc., and KrF (wavelength 248 nm) laser, ArF (wavelength 193 nm) laser, etc.

[0080] The exposure amount is preferably about 10 to 500 mJ / cm 2 (in terms of exposure amount conversion at a wavelength of 365 nm). Examples of the exposure machine include methods such as stepper, mirror projection mask aligner (MPA), parallel light mask aligner (PLA), lens scan, etc. Among these, from the viewpoint of accuracy, the lens scan method is preferred.

[0081] Examples of the method of performing development processing include methods such as shower, dipping, paddle, etc. A method of immersing the film after exposure in the developer for 5 seconds to 10 minutes is preferred. Examples of the developer include aqueous solutions containing inorganic alkalis such as hydroxides, carbonates, phosphates, silicates, borates of alkali metals such as sodium hydroxide and potassium hydroxide; amines such as 2 - diethylaminoethanol, monoethanolamine, diethanolamine; and quaternary ammonium salts such as tetramethylammonium hydroxide and choline, etc., i.e., alkaline developers. After development, it is preferable to rinse with water.

[0082] Examples of alkaline substances used in alkaline developing solutions include inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia; primary amines such as ethylamine and n-propylamine; secondary amines such as diethylamine and di-n-propylamine; tertiary amines such as triethylamine and methyldiethylamine; and organic alkalis such as tetramethylammonium hydroxide.

[0083] After development, the obtained pattern is subjected to a firing process to cure the unreacted components of the photosensitive composition and form a photosensitive composition layer. Firing can be carried out in air, a nitrogen atmosphere, or a vacuum. The firing temperature is preferably 80 to 250°C, and more preferably 150 to 240°C. The firing time is preferably 0.2 to 5 hours, and may be heated continuously or in stages.

[0084] Examples of heating devices include hot plates and ovens. The thickness of the photosensitive composition layer is preferably 1.5 μm or more from the viewpoint of surface smoothness, preferably 3 μm or less, and more preferably 2.6 μm or less from the viewpoint of adjusting the peak full width at half maximum and chromaticity of the transmission spectrum to the aforementioned preferred range and suppressing pixel defects.

[0085] The substrate can be glass or plastic film, and can be transparent or opaque. Examples of glass substrates include soda glass and alkali-free glass, while examples of plastic films include polyester, polyurethane, acrylic, polycarbonate, polyimide, ethylene vinyl alcohol, olefin, and polyacetal. The substrate thickness should be appropriately selected between 10 μm and 3 mm.

[0086] Then, by selecting a transparent substrate and patterning the photosensitive composition layers of the present invention, which contain red, green, and blue colorants, in parallel, a color filter substrate is obtained in which red, green, and blue pixels are formed. In other words, the color filter substrate of the present invention is a color filter substrate in which a photosensitive composition layer made of a cured product of the photosensitive composition of the present invention is formed on a transparent substrate. Alternatively, a color filter substrate may be formed by forming the photosensitive composition layers of the present invention, which contain red, green, and blue colorants, on an array substrate.

[0087] Furthermore, by selecting a substrate on which multiple metal electrodes arranged in an array are formed, and forming a photosensitive composition layer of the present invention over it, a capacitive fingerprint sensor capable of detecting differences in capacitance between the recesses and protrusions of a fingerprint can be obtained. In other words, the fingerprint sensor of the present invention is a fingerprint sensor in which a photosensitive composition layer made of a cured product of the photosensitive composition of the present invention is formed on a substrate on which multiple metal electrodes arranged in an array are formed.

[0088] For example, a liquid crystal display device can be fabricated by placing the color filter substrate of the present invention and the driving element side substrate opposite each other, bonding them together with a spacer in between, injecting liquid crystal through an injection port provided in the seal portion, sealing the injection port, mounting an IC driver and the like, and providing thin-film transistor (TFT) elements on the driving element side substrate in addition to scan lines and signal lines. Alternatively, for example, a display device can be fabricated by installing the color filter substrate of the present invention on the front of an organic EL display or a micro-LED display.

[0089] For example, a display device can also be created that includes the fingerprint sensor of the present invention, a display configured to show a fingerprint registration interface, and a memory for storing a program, and is configured so that the program is executed by a processor, thereby enabling the device to determine whether a touched fingerprint matches or does not match a registered fingerprint. [Examples]

[0090] The present invention will be described below with reference to examples, but the present invention is not limited to these examples. First, the evaluation methods in the examples and comparative examples will be explained. The other components used in each example and comparative example are as follows.

[0091] <Radical polymerizable compounds> C1:3002A(N) (manufactured by Kyoeisha Chemical Co., Ltd., m+n=6, double bond equivalent 300.35g / mol). C1 corresponds to general formula (2). C2: Pentaerythritol triacrylate (double bond equivalent 99.43 g / mol) C3: A-BPE-20 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd., m+n=20, double bond equivalent 608.72 g / mol). C3 corresponds to general formula (2). C4: Ethylene glycol dimethyl acrylate (double bond equivalent 99.11 g / mol) <Photopolymerization initiator> D1: “ADEKA Arcles” (registered trademark) NCI831 (manufactured by ADEKA Corporation) <Organic solvents> E1: Propylene glycol monomethyl ether acetate <Residue Evaluation> The photosensitive compositions obtained in Examples 1-8 and Comparative Examples 1-5 were applied to glass substrates and dried at 90°C for 10 minutes to prepare coated glass substrates. A photosensitive material of 40 mJ / cm² was applied to the i-line through a photomask with a 20 μm line and space pattern. 2 The substrate was exposed to light. Next, it was shower-developed with a 0.2% by mass aqueous solution of tetramethylammonium hydroxide at 23°C for 50 seconds, and then washed with pure water. It was fired at 230°C for 30 minutes to obtain a substrate with a 2.3 μm thick coating. The 20 μm pattern of the coated substrate was measured with an optical microscope and evaluated according to the following evaluation criteria. A: No residue between 20μm patterns B: Residue present between 20μm patterns <Undercut rating> A black matrix with a height of 1.5 μm was prepared on a glass substrate. The photosensitive compositions obtained in Examples 1-8 and Comparative Examples 1-5 were applied to the matrix and dried at 90°C for 10 minutes to prepare a film-formed glass substrate. A photosensitive composition pattern of 40 mJ / cm² was applied to the black matrix via a photomask with a 20 μm line and space pattern, so that the pattern of the photosensitive composition overlapped by 2 μm. 2 The substrate was exposed to light. Next, it was shower-developed with a 0.2% by mass aqueous solution of tetramethylammonium hydroxide at 23°C for 50 seconds, and then washed with pure water. It was fired at 230°C for 30 minutes to obtain a coated substrate with a film thickness of 2.3 μm from the glass in areas where a black matrix was not formed. The cross-section of the substrate was observed to check for the presence or absence of undercuts. For patterns without undercuts, the taper angle on the black matrix substrate was measured. For patterns with undercuts, the depth of the undercut was measured. A: Undercut included B: No undercut <Manufacturing Example 1 (Preparation of Dispersion (A1))> A slurry was prepared by mixing 150g of CI Pigment Green 59, 125g of "BYK" (registered trademark) LPN6919 (manufactured by Bic Chemie, polymer dispersant solution (60% by mass propylene glycol monomethyl ether solution)), 100g of "Cychromer" (registered trademark) ACA250 (manufactured by Daicel Chemical Corporation, 45% by mass dipropylene glycol monomethyl ether solution), and 625g of propylene glycol monomethyl ether (PMA). The beaker containing the slurry was connected to a Dynomill with a tube, and dispersion treatment was performed for 8 hours at a peripheral speed of 14 m / s using 0.5 mm diameter zirconia beads as media to prepare CI Pigment Green 59 dispersion (A1).

[0092] <Manufacturing Example 2 (Preparation of Dispersion (A2))> A dispersion of CI Pigment Yellow 150 (A2) was prepared in the same manner as in Production Example 1, except that CI Pigment Green 59 was replaced with CI Pigment Yellow 150.

[0093] <Manufacturing Example 3 (Synthesis of Alkali-Soluble Resin Solution (B1))> 20 g of methacrylic acid, 20 g of styrene, 8 g of tricyclodecanyl methacrylate, 20 g of methyl methacrylate, 3 g of 2,2'-azobis(2-methylbutyronitrile), and 150 g of PGMEA were charged into a polymerization vessel and stirred at 90°C for 2 hours under a nitrogen atmosphere. The mixture was then raised to 100°C and reacted for a further 5 hours. Next, the polymerization vessel was purged with air, and 10 g of glycidyl methacrylate, 1.2 g of dimethylbenzylamine, and 0.2 g of p-methoxyphenol were added to the resulting reaction solution and stirred at 110°C for 6 hours. The resulting solution was diluted with PGMEA to obtain an alkali-soluble resin solution (B1) with a solid content of 35% by mass (double bond equivalent of alkali-soluble resin: 1171 g / mol, weight ratio of units having a tricyclodecanyl skeleton: 9.7% by mass, acid component: carboxyl group only). Using an AT-610 automatic potentiometer manufactured by Kyoto Electronics Manufacturing Co., Ltd., the acid value of an alkali-soluble resin in a 0.1 mol / L potassium hydroxide-ethanol solution was measured, and the acid value was found to be 109.2 (mgKOH / g). Furthermore, using a GPC instrument, the weight-average molecular weight in polystyrene terms was calculated to be 31,400.

[0094] (Example 1) A photosensitive composition (F1, T / M=412) was prepared by adding 5.53g of dispersion A1 obtained in Production Example 1, 5.64g of dispersion A2 obtained in Production Example 2, 2.84g of alkali-soluble resin solution B1 obtained in Production Example 3, 0.61g of radical polymerizable compound C1, 0.61g of radical polymerizable compound C2, 0.16g of photopolymerization initiator D1, and 14.60g of organic solvent E1 to a 50mL plastic bottle and stirring for 3 hours. When the obtained photosensitive composition was evaluated for residue using the method described above, no residue was observed between 20μm patterns. Furthermore, when the residue was evaluated using the same method, no undercuts were observed and the taper angle was 75 degrees.

[0095] (Examples 2-8, Comparative Examples 1-5) Photosensitive compositions (F2-F13) were obtained in the same manner as in Example 1, except that the types and amounts of the dispersion, alkali-soluble resin solution, radical polymerizable compound, photopolymerization initiator, and organic solvent were changed as shown in Table 1. The results of evaluation using the obtained photosensitive compositions by the method described above are summarized in Table 2.

[0096] [Table 1]

[0097] [Table 2] [Industrial applicability]

[0098] The photosensitive composition of the present invention prevents deformation of the pattern due to excessive flow when firing the photosensitive composition layer, suppresses the development pattern of the photosensitive composition layer from becoming undercut, and reduces the generation of residue. Therefore, it can be used in a color filter substrate having pixels made of a cured product obtained by photocuring the photosensitive composition, or in a fingerprint sensor having the same photocured product, and further, a display device having the same color filter substrate or fingerprint sensor can be provided.

Claims

1. A photosensitive composition comprising an alkali-soluble resin, a radical polymerizable compound, and a photopolymerization initiator, wherein the photosensitive composition contains a bifunctional radical polymerizable compound having a double bond equivalent of 200 to 500, and the ratio T / M of the number of moles M of radical polymerizable groups contained in the photosensitive composition to the total amount T of solids of the organic components satisfies the condition of 320 to 490.

2. The photosensitive composition according to claim 1, wherein the difunctional radical polymerizable compound comprises general formula (1). 【Chemistry 1】 However, R １ ~R ８ Each of these is independently a hydrogen atom, an acrylic group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms.

3. The photosensitive composition according to claim 1 or 2, wherein the bifunctional radical polymerizable compound comprises general formula (2). 【Chemistry 2】 However, m and n are each 1 or greater, and m+n is between 3 and 6.

4. The photosensitive composition according to claim 1, wherein the alkali-soluble resin has a tricyclodecanyl skeleton.

5. The photosensitive composition according to claim 4, wherein the mass ratio of units having a tricyclodecanyl skeleton contained in the alkali-soluble resin is 2% by mass or more and 30% by mass or less in the alkali-soluble resin.

6. The photosensitive composition according to claim 1 or 2, wherein the content of the alkali-soluble resin is 10% by mass or more and 30% by mass or less in solid content.

7. The photosensitive composition according to claim 1 or 2, wherein the photosensitive composition contains a green colorant having a metal phthalocyanine skeleton, and the light transmittance at 350 to 380 nm is 1% or more and 5% or less.

8. A color filter substrate having pixels made of a photocured product of the photosensitive composition described in claim 1.

9. A fingerprint sensor having a photocured product of the photosensitive composition according to claim 1.

10. A display device having a color filter substrate according to claim 8 or a fingerprint sensor according to claim 9.

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