KR20140110385A - White photosensitive resin composition - Google Patents

Abstract

The present invention relates to a white photosensitive resin composition which comprises: (1) a copolymer including (1-1) a unit derived from ethylene unsaturated carboxylic acid, ethylene unsaturated carboxylic acid anhydride, or a mixture of the same, and (1-2) a unit derived an aromatic ring-containing ethylene unsaturated compound; (2) a coloring agent including (2-1) white dye and (2-2) inorganic filler; (3) a polymerizable unsaturated compound; and (4) an photopolymerization initiator, and which not only has excellent heat-resistant and chemical-resistant properties, but also has high light shading properties to be used in manufacturing of a white bezel of a display of mobile phones, tablet PCs, and various portable devices.

Description

WHITE PHOTOSENSITIVE RESIN COMPOSITION [0002]

The present invention relates to a white photosensitive resin composition, and more particularly, to a white photosensitive resin composition useful as a white bezel material for a display of a mobile phone, a tablet computer (tablet PC) and various portable devices.

The display portion of a portable device such as a mobile phone and a tablet PC is composed of a top plate on which a cover glass printed with an ink for imparting a color of a part of the bezel and a touch sensor are adhered and a display device using an existing liquid crystal display device or an organic light emitting device have. In recent years, a conductive film is deposited on a cover glass, patterned through etching, and then a conductive film is formed between the conductive film and the conductive film. Has developed into a form using a thermosetting overcoat for insulation.

Accordingly, since the layer corresponding to the bezel of the display portion becomes the first layer of the touch sensor, a high level of heat resistance and chemical resistance are required for the formation of the conductive pattern and the high temperature and etching required for forming the insulating layer.

Further, in order to realize a plurality of bezels corresponding to individual product sizes simultaneously at a precise position in a cover glass having a large area through conventional screen printing, problems are presented in the flatness of the film, repetitive reproducibility of the position of the bezel, Attempts have been made to use photosensitive resins.

However, in the case of a white bezel, it is difficult to manufacture a thin film because of its low optical density to shade the inside light, and it is difficult to apply a photosensitive resin because its heat resistance and chemical resistance are very poor.

Accordingly, an object of the present invention is to provide a white photosensitive resin composition which is excellent in heat resistance and chemical resistance, has a high light shielding property, and can be usefully used as a white bezel material for displays of mobile phones, tablet PCs and various portable devices In particular, it is intended to provide a white photosensitive resin composition containing an inorganic filler in addition to a white pigment as a colorant, which can be produced at a lower cost by achieving a high optical density while reducing the amount of white pigment used.

In order to achieve the above object, the present invention relates to (1) a resin composition comprising (1-1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof, and (1-2) A copolymer comprising a constituent unit derived from a compound; (2) a colorant comprising (2-1) a white pigment and (2-2) an inorganic filler; (3) a polymerizable unsaturated compound; And (4) a photopolymerization initiator.

The white photosensitive resin composition of the present invention is excellent in heat resistance and chemical resistance, and has high light shielding properties, and thus can be usefully used in the manufacture of white bezels of displays for mobile phones, tablet PCs, and various portable devices.

The white photosensitive resin composition according to the present invention comprises (1) a structural unit derived from (1-1) an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride or a mixture thereof, and (1-2) a structural unit derived from an aromatic ring- A copolymer comprising a constituent unit derived from a compound; (2) a colorant comprising (2-1) a white pigment and (2-2) an inorganic filler; (3) a polymerizable unsaturated compound; And (4) a photopolymerization initiator and, if necessary, (5) a silane coupling agent, (6) a surfactant, and / or (7) a solvent.

Hereinafter, the constituent components of the present invention will be described in detail.

(1) Copolymer

The copolymer includes (1-1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof, and (1-2) a structural unit derived from an aromatic ring-containing ethylenically unsaturated compound (1) a structural unit derived from an unsaturated monomer containing a Si-O skeleton in the side chain (1-3), or (1-4) a structural unit derived from an ethylene And may contain a constitutional unit derived from an unsaturated compound.

(1-1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof

In the present invention, the constituent unit (1-1) is derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof, wherein the ethylenically unsaturated carboxylic acid, ethylenically unsaturated carboxylic acid anhydride, (Meth) acrylic acid, crotonic acid, alpha-chloroacrylic acid and cinnamic acid; unsaturated monocarboxylic acids such as (meth) acrylic acid, crotonic acid, alpha-chloroacrylic acid and cinnamic acid; Unsaturated dicarboxylic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride and mesaconic acid, and anhydrides thereof; Unsaturated polycarboxylic acids of trivalent or more and their anhydrides; Mono [(meth) acryloyloxyalkyl] acrylate of a dicarboxylic or higher polycarboxylic acid such as mono [2- (meth) acryloyloxyethyl] succinate and mono [2- (meth) acryloyloxyethyl] And esters. Among them, (meth) acrylic acid can be preferably used from the viewpoint of developability.

The content of the constituent unit derived from the (1-1) ethylenically unsaturated carboxylic acid, the ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof may be from 5 to 98 mol% based on the total number of moles of the constituent units constituting the copolymer, And preferably 15 to 50 mol% in order to maintain developability.

In the present invention, the terms (meth) acrylate and (meth) acrylate refer to acrylic and / or methacrylic, and acrylate and / or methacrylate, respectively.

(1-2) a structural unit derived from an aromatic ring-containing ethylenically unsaturated compound

In the present invention, the structural unit (1-2) is derived from an aromatic ring-containing ethylenically unsaturated compound, and the aromatic ring-containing ethylenically unsaturated compound is selected from the group consisting of phenyl (meth) acrylate, benzyl (meth) acrylate, (Meth) acrylate, p-nonylphenoxypolyethylene glycol (meth) acrylate, p-nonylphenoxypolypropylene glycol (meth) acrylate, tribromophenyl (meth) Acrylate; Styrene; Styrene having alkyl substituents such as methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene and octylstyrene; Styrene having a halogen such as fluorostyrene, chlorostyrene, bromostyrene, and iodostyrene; Styrene having an alkoxy substituent such as methoxystyrene, ethoxystyrene, propoxystyrene; 4-hydroxystyrene, p-hydroxy-a-methylstyrene, acetyl styrene; Vinyl benzyl methyl ether, m-vinyl benzyl methyl ether, p-vinyl benzyl methyl ether, o-vinyl benzyl glycidyl ether, m-vinyl benzyl glycidyl ether, and p-vinylbenzyl glycidyl ether, and the like. Of these, styrene-based compounds are preferable in view of polymerizability.

The content of the constituent unit derived from the (1-2) aromatic ring-containing ethylenically unsaturated compound may be from 2 to 95 mol% based on the total molar amount of the constituent unit constituting the copolymer, and preferably from 10 To 60 mol%.

(1-3) a structural unit derived from an unsaturated monomer containing a Si-O skeleton in a side chain

In the present invention, the constituent unit (1-3) is derived from an unsaturated monomer containing a Si-O skeleton in the side chain, and preferably such a monomer can be represented by the following formula (1)

In Formula 1,

R ₁ is hydrogen or a straight, branched or cyclic alkyl group of 1 to 8 carbon atoms,

R ₂ is a single bond or an alkylene group having 1 to 5 carbon atoms,

R ₃ and R ₄ are each independently hydrogen, a straight, branched or cyclic alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 18 carbon atoms,

R ₅ is hydrogen, a methyl group, or an ethyl group,

n is an integer of 2 to 20;

(1-4) Structural unit derived from an ethylenically unsaturated compound which is different from the above-mentioned constituent units (1-1) to (1-3)

Specific examples of the structural unit derived from the ethylenically unsaturated compound which is different from (1-4) the structural units (1-1) to (1-3) include methyl (meth) acrylate, ethyl (meth) Acrylates such as butyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl Hydroxypropyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxyethyl (meth) acrylate, 2-hydroxypropyl (Meth) acrylate, glycerol (meth) acrylate, methyl? -Hydroxymethylacrylate, ethyl? -Hydroxymethylacrylate, propyl? -Hydroxymethylacrylate, butyl? -Hydroxymethylacrylate, 2- Methoxyethyl (meth) (Meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, poly (ethylene glycol) ) Methyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, 1,1,1,3,3,3-hexafluoroisopropyl (meth) acrylate, octafluoropentyl (Meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentanyl Unsaturated carboxylic acid esters including dicyclopentenyloxyethyl (meth) acrylate; N-vinyl tertiary amines including N-vinyl, such as N-vinylpyrrolidone, N-vinylcarbazole and N-vinylmorpholine; Unsaturated ethers including vinyl methyl ether and vinyl ethyl ether; (Meth) acrylate, 5,6-epoxyhexyl (meth) acrylate, 6,7-epoxy (meth) acrylate, (Meth) acrylate,? -Ethylglycidyl acrylate,? -N-propylglycidyl (meth) acrylate, Acrylate,? -N-butylglycidyl acrylate, N- (4- (1,3-epoxypropoxy) -3,5-dimethylbenzyl) acrylamide, N- One or more epoxy groups such as hydroxyethyl (meth) acrylate, hydroxyethyl (meth) acrylate, glycidyl methacrylate, Unsaturated monomers including; Unsaturated imides including N-phenylmaleimide, N- (4-chlorophenyl) maleimide, N- (4-hydroxyphenyl) maleimide and N-cyclohexylmaleimide. In particular, it may be an ethylenically unsaturated compound including an epoxy group in terms of copolymerization and strength improvement of an insulating film, and may preferably be glycidyl (meth) acrylate.

A structural unit derived from an unsaturated monomer having a Si-O skeleton in the side chain (1-3), or (1-4) a structural unit derived from an ethylenically unsaturated compound different from the structural units (1-1) to (1-3) Can be 0 to 60 mol%, preferably 10 to 55 mol%, based on the total molar amount of the constituent units constituting the copolymer. Within the above range, the storage stability of the white photosensitive resin composition is maintained, and the heat resistance and residual film ratio of the coating film are improved.

The copolymer according to the present invention may be prepared by adding a molecular weight regulator, a polymerization initiator, a solvent, an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof, and an aromatic ring-containing ethylenically unsaturated compound, And adding an unsaturated monomer or other ethylenically unsaturated compound containing a skeleton, and adding nitrogen, followed by polymerization while slowly stirring.

The weight average molecular weight (Mw) of the prepared copolymer in terms of polystyrene measured by gel permeation chromatography (GPC; tetrahydrofuran as an elution solvent) may be 3,000 to 50,000, preferably 5,000 to 40,000 . In the above range, adhesion with the substrate is excellent, physical and chemical properties are good, and viscosity is appropriate.

The molecular weight modifier is not particularly limited, but may be a mercaptan compound such as butylmercaptan, octylmercaptan or the like or? -Methylstyrene dimer.

The polymerization initiator is not particularly limited, Diazo compounds such as 2,2'-azobis (2,4-dimethylvaleronitrile) or 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), and benzoyl peroxide , Lauryl peroxide, t-butyl peroxypivalate or 1,1-bis (t-butylperoxy) cyclohexane.

The solvent may be any solvent used in the production of the copolymer, preferably propylene glycol monomethyl ether acetate (PGMEA).

The copolymer may be contained in the photosensitive resin composition alone or in combination of two or more. The copolymer may be an alkali-soluble resin that realizes developability in the development step, and may serve as a base for performing a base role of forming a coating film after coating and a final pattern.

The content of the copolymer to be used may be 0.5 to 60% by weight based on the total weight of the photosensitive resin composition excluding the solvent (based on the solid content), preferably 5 To 50% by weight. Within the above range, the pattern development after development is favorable and the characteristics such as chemical resistance are improved.

(2) Colorant

The white photosensitive resin composition of the present invention is a coloring agent for imparting light blocking properties to a white bezel, wherein the coloring agent is composed of (2-1) a white pigment and (2-2) an inorganic filler.

(2-1) White pigment

As the white pigment to be used in the present invention, a pigment having high coloring property and high heat resistance is preferably used as the inorganic pigment.

The white pigment may be any of those known in the art and may be at least one selected from the group consisting of titanium oxide, barium sulfate, talc, barium carbonate, alkaline magnesium carbonate, alumina white, gross white, and satin white. Among them, titanium oxide is preferable in terms of optical density.

(2-2) Inorganic filler

When the inorganic filler used in the present invention is included, the heat resistance of the white photosensitive resin composition is improved, and even if the amount of the white pigment used in (2-1) is reduced, the same level of light shielding property can be secured.

Specific examples of the inorganic filler include inorganic fillers such as silica, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate, magnesium titanate , Bismuth titanate, barium zirconate, and calcium zirconate. Among them, silica is preferable in terms of heat resistance and optical density.

The silica is not limited to a production method such as a gas phase reaction or a liquid phase reaction or a shape (spherical or non-spherical) in the case of granular silica, but it is preferably an amorphous granular silica synthesized by a vapor phase method in that it has low cohesion and excellent dispersibility . The particle diameter of the particulate silica may be 10 to 300 nm, preferably 50 to 150 nm, and the average value is preferably 100 nm. When the particle diameter exceeds 300 nm, the heat resistance is the same as the particle size of 100 nm, but the surface roughness of the coating film becomes large and a good white photosensitive resin can not be formed.

The weight ratio of the above-mentioned (2-1) white pigment and (2-2) inorganic filler may be 40:60 to 95: 5, and preferably 50:50 to 95: 5. When the inorganic filler is used together with the white pigment in the above range, the heat resistance can be improved and the optical density of the same level can be secured as compared with the case of using the white pigment alone.

Meanwhile, a dispersant may be used to disperse the colorant in the white photosensitive resin composition of the present invention. The dispersant may be any of those known as pigment dispersants. Specific examples thereof include a cationic surfactant, an anionic surfactant, a nonionic surfactant, an amphoteric surfactant, a silicone surfactant, and a fluorinated surfactant. have. Commercially available dispersing agents include Disperbyk-182, Disperbyk-183, Disperbyk-184, Disperbyk-185, Disperbyk-2000, Disperbyk-2150, Disperbyk-2155, Disperbyk-2163 and Disperbyk-2164 of BYK. These may be used alone or in combination of two or more.

The dispersing agent may be added to the interior of the coloring agent by previously surface-treating the coloring agent, or may be used in the production of the white photosensitive resin composition together with the coloring agent.

The colorant may be mixed with a binder and then used in the production of a white photosensitive resin composition. The binder used herein may be one or more materials selected from the above-mentioned (1) copolymer or a known copolymer as described in the present invention.

The content of the (2) colorant may be 5 to 75% by weight, preferably 10 to 65% by weight based on the total weight of the colored photosensitive resin composition excluding the solvent (based on the solid content). When the content of the colorant is within the above range, it is possible to prevent the optical density from becoming too low, achieve high optical density, and improve the processability such as developability.

(3) Polymerizable unsaturated compound

The polymerizable unsaturated compound is a compound which can be polymerized by the action of a polymerization initiator, and is a monomer, oligomer or polymer generally used in a photosensitive resin composition, and may be a copolymer of acrylic acid or methacrylic acid having at least one ethylenic unsaturated double bond Functional or multifunctional ester compound, but from the viewpoint of chemical resistance, it may preferably be a multifunctional compound having two or more functional groups.

Wherein the polymerizable unsaturated compound is at least one selected from the group consisting of ethyleneglycol di (meth) acrylate, propyleneglycol di (meth) acrylate, diethyleneglycol di (meth) acrylate, triethyleneglycol di (meth) (Meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tri (meth) Acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, pentaerythritol tri (Meth) acrylate, monoesters of dipentaerythritol penta (meth) acrylate and succinic acid, caprolactone-modified di (Reaction product of pentaerythritol triacrylate and hexamethylene diisocyanate), tripentaerythritol hepta (meth) acrylate, pentaerythritol triacrylate hexamethylene diisocyanate (reaction product of pentaerythritol triacrylate and hexamethylene diisocyanate), tripentaerythritol But are not limited to, at least one selected from the group consisting of lithol octa (meth) acrylate, bisphenol A epoxy acrylate, and ethylene glycol monomethyl ether acrylate.

When the polymerizable unsaturated compound is used as an oligomer or polymer, it may have a weight average molecular weight of 6,000 to 10,000.

The content of the polymerizable compound may be 5 to 60% by weight, preferably 10 to 55% by weight based on the total weight (solid content) of the photosensitive resin composition excluding the solvent. When the thickness is within the above range, pattern formation is easy, and a problem of a pattern shape such as scum is not generated at the lower end during development.

(4) Photopolymerization initiator

The white photosensitive resin composition of the present invention includes a photopolymerization initiator and is not limited as long as it is a photopolymerization initiator used in the art.

Examples of the photopolymerization initiator include an acetophenone based compound, a nonimidazole based compound, a triazine based compound, an onium salt based compound, a benzoin based compound, a benzophenone based compound, a diketone based compound, an? - diketone based compound, a polynuclear quinone based compound, There may be mentioned a photopolymerization initiator composed of an acid-tonide compound, a diazo compound, an imide sulfonate compound, an oxime compound, a carbazole compound, a sulfonium borate compound, and a mixture thereof, preferably an oxime ester-based photopolymerization initiator It can be the best.

Examples of the oxime ester-based photopolymerization initiator include those disclosed in Korean Patent Publication Nos. 2004-7700, 2005-84149, 2008-83650, 2008-80208, 2007-44062, 2007-91110, 2007- 44753, 2009-9991, 2009-93933, 2010-97658 or 2011-59525, WO 2010/102502 or WO 2010/133077 are preferred, , And commercial products such as OXE-01, OXE-02 (manufactured by Ciba) and N-1919 (manufactured by ADEKA) are preferable in view of high sensitivity and resolution.

The photopolymerization initiator may be used in an amount of 0.01 to 10% by weight, preferably 0.2 to 5% by weight based on the total weight of the photosensitive resin composition excluding the solvent (based on the solid content). In this range, the curing is sufficiently achieved by exposure, and it is easy to obtain a white pattern and can be sufficiently adhered to the substrate.

(5) Silane coupling agent

The white photosensitive resin composition according to the present invention may further include a silane coupling agent to improve adhesion to the substrate. Such a silane coupling agent may have a reactive substituent selected from the group consisting of, for example, a carboxyl group, (meth) acryloyl group, isocyanate group, amino group, mercapto group, vinyl group, epoxy group and combinations thereof.

The kind of the silane coupling agent is not particularly limited, and examples thereof include trimethoxysilylbenzoic acid,? -Methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane,? -Isocyanatopropyltri Glycidoxypropyltrimethoxysilane,? -Glycidoxypropyltriethoxysilane,? - (3,4-epoxycyclohexyl) ethyltrimethoxysilane, and mixtures thereof can be exemplified Isocyanatopropyltriethoxysilane (KBE-9007, Shin-Etsu) having an isocyanate group with good adhesion to the substrate while maintaining chemical resistance.

The content of the silane coupling agent may be 0.1 to 10% by weight, preferably 0.2 to 5% by weight based on the total weight of the photosensitive resin composition excluding the solvent (based on the solid content). Within the above range, the adhesion of the white photosensitive resin composition can be improved.

(6) Surfactant

The white photosensitive resin composition of the present invention may further contain a surfactant for improving coatability and preventing defect formation, if necessary. The kind of the surfactant is not particularly limited, but it may preferably be a fluorine-based surfactant or a silicon-based surfactant. Examples of commercial products of the above fluorine-based surfactants include Megafiz F-470, F-471, F-475, F-482 and F-489 manufactured by Dainippon Ink and Chemicals, Incorporated. Of these, BYK 333 manufactured by BYK Corporation may preferably be used in terms of dispersibility. Examples of commercially available silicone surfactants include DC3PA, DC7PA, SH11PA, SH21PA, SH8400, and TSF-4440, TSF-4300, TSF-4445, TSF-4446, TSF-4460 and TSF-4452 of GE Toshiba Silicone Co., , BYK 333 manufactured by BYK, and the like. These may be used alone or in combination of two or more.

The surfactant may be used in an amount of 0.05 to 10% by weight, preferably 0.1 to 5% by weight based on the total weight of the photosensitive resin composition excluding the solvent (based on the solid content). Within this range, the coating of the white photosensitive resin composition is smooth.

(7) Solvent

The white photosensitive resin composition of the present invention can be prepared by a conventional method, and preferably, a liquid composition in which the above-mentioned components are mixed with a solvent.

The solvent is compatible with the above white photosensitive resin composition components and does not react with the above white photosensitive resin composition components, and any known solvent used in the photosensitive resin composition can be used. Examples of such solvents include glycol ethers such as ethylene glycol monoethyl ether; Ethylene glycol alkyl ether acetates such as ethyl cellosolve acetate; Esters such as ethyl 2-hydroxypropionate; Diethylene glycol such as diethylene glycol monomethyl ether; And propylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate and propylene glycol propyl ether acetate. These solvents may be used alone or in combination of two or more.

The content of the solvent is not particularly limited, but may be an amount such that the total concentration of each component other than the solvent of the composition is usually from 5 to 70% by weight from the standpoint of coatability, stability, and the like of the obtained white photosensitive resin composition, Preferably 10 to 55% by weight.

In addition, the white photosensitive resin composition of the present invention may contain other additives such as antioxidants and stabilizers within a range not lowering the physical properties.

As an example of the method for producing the white photosensitive resin composition of the present invention, the following method can be exemplified.

The white pigment and the inorganic filler are mixed with the solvent in advance and dispersed using a bead mill or the like until the average particle diameter of each of the white pigment and the inorganic filler reaches a desired level. At this time, a surfactant may be used if necessary, and some or all of the copolymer may be blended. A copolymer, a polymerizable unsaturated compound, a photopolymerization initiator and, if necessary, a silane coupling agent are added to the resulting dispersion, and further additives or an additional solvent are further added thereto so as to have a predetermined concentration, if necessary, A photosensitive resin composition can be obtained.

The present invention also provides a white bezel produced using the white photosensitive resin composition.

The white bezel is manufactured through a film forming step, an exposure step, a development step, and a heat treatment step.

In the coating film forming step, the white photosensitive resin composition according to the present invention is coated on a predetermined pretreated substrate by a method such as spin or slit coating method, roll coating method, screen printing method, applicator method, And the solvent is removed by heating at a temperature of 70 to 90 DEG C for 1 to 10 minutes to form a coating film.

In order to form a pattern necessary for the obtained coating film, an active line of 200 to 500 nm is irradiated after a predetermined type of mask is interposed. As the light source used for the irradiation, a low pressure mercury lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp, an argon gas laser, and the like can be used. The exposure dose varies depending on the kind of each component of the composition, the blending amount and the dried film thickness, but may be 500 mJ / cm ² (at a wavelength of 365 nm) or less when a high-pressure mercury lamp is used.

Following the above exposure step, an unnecessary portion is dissolved and removed by using an alkaline aqueous solution of sodium carbonate, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, or the like as a developing solution, so that only the exposed portion can be left to form a pattern. After the image pattern obtained by the development is cooled to room temperature, it is post-baked in a hot air circulation type drying oven at 180 ° C to 250 ° C for 10 minutes to 60 minutes to finally obtain a desired pattern.

As described above, the white photosensitive resin composition according to the present invention has excellent heat resistance and chemical resistance, and has high light shielding characteristics, and thus can be usefully used in the manufacture of white bezels for displays of mobile phones, tablet PCs and various portable devices. For example, the white photosensitive resin composition of the present invention may have an optical density of 0.5 or more (at the time of forming a 1 占 퐉 thick cured film), and preferably an optical density of 0.5 to 2.0.

Accordingly, the present invention provides an electronic component including the white bezel.

The display of the present invention may include configurations known to those skilled in the art, except for having a white bezel of the present invention. That is, all of the displays to which the white bezel of the present invention can be applied can be included in the present invention.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are intended to illustrate the present invention, but the scope of the present invention is not limited thereto.

The weight average molecular weight described in the following Production Examples is a polystyrene reduced value measured by gel permeation chromatography (GPC).

Preparation Example 1: Preparation of copolymer A

400 parts by weight of propylene glycol monomethyl ether acetate (PGMEA) was introduced into a four-necked flask equipped with a thermometer, a cooling tube, a nitrogen gas introducing tube and a stirrer and heated to 80 DEG C, A mixture of 2 parts by weight of 2,2'-azobisisobutyronitrile, 57 parts by weight of benzyl methacrylate, 13 parts by weight of methacrylic acid and 30 parts by weight of methacryloxypolysiloxane (product name: silaplane TM0701, manufactured by Chisso Corporation) Was added dropwise over 2 hours. After completion of the dropwise addition, the reaction was further continued for 3 hours to obtain an acrylic copolymer resin solution having a siloxane skeleton in the side chain having a weight average molecular weight (Mw) of 12,500. After cooling to room temperature, about 2 parts by weight of the resin solution was sampled, heated and dried at 180 DEG C for 20 minutes, and then solid content was measured. Propylene glycol monomethyl ether acetate (PGMEA) was added to the resin solution so that the solid content was 20 wt% To obtain a copolymer A. < tb >< TABLE >

Production Example 2: Preparation of Copolymer B

Except that 35 parts by weight of methyl methacrylate was used instead of methacryloxypolysiloxane, 50 parts by weight of benzyl methacrylate and 15 parts by weight of methacrylic acid were used, and the weight average molecular weight 13, 100, and a solid content of 20%.

Production Example 3: Preparation of white pigment dispersion

6 g of polymer dispersant (DISPERBYK ^占 -2000), 120 g of white pigment TiO ₂ and 74 g of PGMEA were dispersed in a paint shaker at 25 to 60 占 폚 for 6 hours. 0.3 mm zirconia beads were used to disperse the beads. After the dispersion was completed, the beads and the dispersion liquid were separated by a filter to prepare white white pigment dispersions.

Production Example 4: Preparation of an inorganic filler dispersion

6 g of polymer dispersant (DISPERBYK ^占 -2000), 51 g of inorganic filler silica and 74 g of PGMEA were dispersed in a paint shaker at 25 to 60 占 폚 for 6 hours. Dispersion was performed using 0.3 mm zirconia beads. After the dispersion was completed, the beads and the dispersion were separated by a filter to prepare a white dispersion of a final inorganic filler.

Example 1

1.6516 g of the copolymer A prepared in Preparation Example 1, 2.9108 g of the white pigment dispersion (solid content 60%) prepared in Preparation Example 3, 1.1082 g of the inorganic filler dispersion (solid content 39.4%) prepared in Preparation Example 4, 0.3188 g of dipentaerythritol hexaacrylate (trade name: DPHA, Nippon Kayaku) as an unsaturated compound, 0.06 g of an oxime-based photopolymerization initiator (trade name: OXE-02, Ciba Specialty Chemicals Inc.), a surfactant (trade name: BYK- And 3.9297 g of propylene glycol monomethyl ether acetate (PGMEA) as a solvent were mixed and stirred to prepare a white photosensitive resin composition.

Examples 2 to 4

A white photosensitive resin composition was prepared in the same manner as in Example 1 except that its content was changed as shown in Table 1.

Comparative Example 1

A colored photosensitive resin composition was prepared in the same manner as in Example 1, except that its content was changed as shown in Table 1.

Test Example  1: Resolution measurement

≪ Preparation of specimen &

Each of the white photosensitive resin compositions obtained in Examples 1 to 4 and Comparative Example 1 was applied to a glass substrate using a spin coater and then dried at 90 DEG C for 100 seconds to form a coating film having a thickness of 4.0 mu m. The obtained coating film was irradiated with light having a wavelength of 365 nm at a dose of 100 mJ / cm 2 using a pattern mask. Subsequently, the resultant was developed in an aqueous solution diluted with 1 wt% of potassium hydroxide at 25 DEG C for 60 seconds, and then washed with pure water for 1 minute. By this operation, unnecessary portions were removed and only the pattern was left. The formed pattern was cured by heating in an oven at 230 캜 for 30 minutes to finally obtain a white pattern.

<Resolution Measurement>

For each of the specimens obtained in the production of the specimen, the resolution was measured by observing the minimum size of the white pattern using a micro-optical microscope. The results are shown in Table 2. The smaller the value, the better.

Test Example  2: Chemical  Adhesion measurement

Using the white photosensitive resin compositions obtained in Examples 1 to 4 and Comparative Example 1, white films each having a thickness of 3.0 (+/- 0.2) 占 퐉 were prepared in the same manner as in the preparation of the test piece of Test Example 1 described above. Each of the prepared white films was immersed in a NaOH solution and a quench solution at 45 캜 for 90 seconds each. The immersed sample was thoroughly washed with distilled water, and then dried in an oven at 110 DEG C for 2 minutes. The adhesion of the film to the sample was evaluated using the method of ASTM D3359, and the degree of adhesion was shown in Table 2. At this time, the adhesion was evaluated according to the following criteria.

0B: crumbled with flakes and fell off by more than 65%

1B: The cut edge and the lattice are separated and the area is more than 35% and less than 65%

2B: The cut edge and part of the lattice are separated and the area is more than 15% but less than 35%

3B: A small area has fallen off at the end and intersection of the cut part and the area is more than 5% but less than 15%

4B: The area of the cut-off area at the intersection of the cut part is less than 5%

5B: The edge of the cut is smooth and there is no grating off

Test Example 3: Measurement of chemical resistance

Each of the white films having a thickness of 3.0 (± 0.2) μm prepared in Test Example 2 was measured with a colorimeter (MCPD-7000, manufactured by Otsuka Electronics Co., Ltd.) (L ₁ , a ₁ , b ₁ ) And immersed in a NaOH solution and a quench solution at 45 캜 for 90 seconds, respectively. The immersed sample was thoroughly washed with distilled water, and then dried in an oven at 110 DEG C for 2 minutes. Thereafter, the white film was again measured (L ₂ , a ₂ , b ₂ ) using a colorimeter, and color difference was calculated using the following equation (1). The results are shown in Table 2. The smaller the value, the better.

[Equation 1]

? Eab =? (L ₂ -L ₁ ) ² + (a ₂ -a ₁ ) ² + (b ₂ -b ₁ ) ²

Test Example 4: Measurement of heat resistance

Each of the white films having a thickness of 3.0 (± 0.2) μm prepared in Test Example 2 was measured with a colorimeter (MCPD-7000, manufactured by Otsuka Electronics Co., Ltd.) (L ₁ , a ₁ , b ₁ ) In an oven for 30 minutes and then cooled at room temperature. Then, the white film was again measured (L ₂ , a ₂ , b ₂ ) using a colorimeter, and the color difference was calculated using the above equation (1). The results are shown in Table 2. The smaller the value, the better.

Test Example 5: Optical density measurement

The transmittance at 550 nm was measured for each of the white films having a thickness of 3.0 (± 0.2) μm prepared in Test Example 2 using a UV-vis equipment (Cary 100, Varian), and the transmittance was measured using the following equation And optical density was obtained. The results are also shown in Table 2. The larger the value, the better.

&Quot; (2) &quot;

Optical density = log (100 / T _{550 nm} )

Test Example 6: Developability Measurement

The developability of the specimen of Test Example 1 was measured during the development process.

The measurement was started at the moment when the developer reached the surface of the coating film, and the time until the bottom of the glass substrate was exposed was recorded as a break point (BP). The results are also shown in Table 2.

From the experimental results of Table 2, it was found that when a white pattern or a white film is produced using the white photosensitive resin compositions of Examples 1 to 4 according to the present invention, it has excellent resolution, chemical resistance, heat resistance and chemical resistance, It was found that the optical density was excellent.

Claims (7)

(1) A resin composition comprising (1-1) a structural unit derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a mixture thereof, and (1-2) a structural unit derived from an aromatic ring- Copolymer;
(2) a colorant comprising (2-1) a white pigment and (2-2) an inorganic filler;
(3) a polymerizable unsaturated compound; And
(4) Photopolymerization initiator
And a photopolymerization initiator.
The method according to claim 1,
The copolymer (1) contains the constituent units (1-1) and (1-2) in an amount of 5 to 98 mol% and 2 to 95 mol%, respectively, relative to the total molar amount of the constituent units constituting the copolymer , Add to
(1-3) a structural unit derived from an unsaturated monomer containing a Si-O skeleton in the side chain or (1-4) a structural unit derived from an ethylenically unsaturated compound different from the structural units (1-1) to (1-3) Wherein the composition contains the derived constituent units in an amount of 0 to 60 mol%.
3. The method of claim 2,
Wherein the unsaturated monomer having a Si-O skeleton in the side chain is represented by the following formula (1): &lt; EMI ID =
[Chemical Formula 1]

In Formula 1,
R ₁ is hydrogen or a straight, branched or cyclic alkyl group of 1 to 8 carbon atoms,
R ₂ is a single bond or an alkylene group having 1 to 5 carbon atoms,
R ₃ and R ₄ are each independently hydrogen, a straight, branched or cyclic alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 18 carbon atoms,
R ₅ is hydrogen, a methyl group, or an ethyl group,
n is an integer of 2 to 20;
The method according to claim 1,
Wherein the white pigment is at least one selected from the group consisting of titanium oxide, barium sulfate, talc, barium carbonate, alkaline magnesium carbonate, alumina white, gross white and satin white.
The method according to claim 1,
Wherein the inorganic filler is selected from the group consisting of silica, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium oxide, boron nitride, aluminum borate, barium titanate, calcium titanate, magnesium titanate, bismuth titanate, barium zirconate and calcium zirconate Type or more.
The method according to claim 1,
Wherein the photosensitive resin composition has an optical density of 0.5 or more (at the time of forming a 1 占 퐉 thick cured film).
The method according to claim 1,
Wherein the colorant comprises (2-1) a white pigment and (2-2) an inorganic filler in a weight ratio of 40:60 to 95: 5.