KR102345980B1 - Photosensitive resin composition and method of forming pattern using the same - Google Patents

Abstract

The photosensitive resin composition according to an embodiment of the present invention contains 0.1 to 20 parts by weight of a radical photoinitiator, 0.1 to 10 parts by weight of an ionic photoinitiator, 1 to 50 parts by weight of a polyfunctional acrylate oligomer, and 1 to 50 parts by weight of an ethylenically unsaturated based on 100 parts by weight of the acrylic copolymer. 1 to 50 parts by weight of a polyfunctional monomer having a bond, and a solvent.

Description

Photosensitive resin composition and pattern formation method using the same

The present invention relates to a photosensitive resin composition and a pattern forming method using the same.

2. Description of the Related Art In general, a display device is a widely used display device, and there are several types such as a liquid crystal display (LCD) and an organic light emitting display (OLED). Also, recently, a display device in which the display device is bent to form a curved surface has been attracting attention, which improves the user's sense of immersion.

In the process of forming such a display device, a photo process may be used to pattern a film, and in this case, a photoresist material is used. Alternatively, a layer may be formed directly by exposing and developing a photoresist material.

An insulating film, a column spacer, an overcoat layer, and a color filter layer can be formed using such a photoresist, and the resolution, adhesive force, remaining film rate, etc. are affected according to the composition of the photosensitive resin composition for forming the photoresist.

Embodiments are to provide a photosensitive resin composition capable of curing at a low temperature, having excellent sensitivity and film remaining rate, and excellent residue properties, and a pattern forming method using the same.

The photosensitive resin composition according to an embodiment of the present invention contains 0.1 to 20 parts by weight of a radical photoinitiator, 0.1 to 10 parts by weight of an ionic photoinitiator, 1 to 50 parts by weight of a polyfunctional acrylate oligomer, and 1 to 50 parts by weight of an ethylenically unsaturated based on 100 parts by weight of the acrylic copolymer. 1 to 50 parts by weight of a polyfunctional monomer having a bond, and a solvent.

The photosensitive resin composition may be cured at a temperature of 90 °C or less.

The radical photoinitiator is 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione or 2-(O-acetyloxime)-1-[4-(phenylthio) phenyl]-1,2-octanedione.

The ionic photoinitiator is phenyl (4-methoxyphenyl) iodonium hexafluoride, N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid, 4-methylphenyl (4- (2-methylpropylphenyl)) iodonium hexafluoride , and phenyl (4-methoxyphenyl) may be at least one selected from the group consisting of iodonium arsenic hexafluoride.

The content ratio of the radical photoinitiator and the ionic photoinitiator may be 2:1 to 1:2.

The photosensitive resin composition may have a solid content of 10 wt% to 50 wt%.

The photosensitive resin composition may further include a melamine crosslinking agent.

The photosensitive resin composition may further include a silane coupling agent.

The acrylic copolymer may be formed by copolymerizing an unsaturated carboxy compound and an unsaturated olefin compound.

The solvent may have a boiling point of less than 150°C.

The pattern forming method according to an embodiment of the present invention comprises the steps of coating a photosensitive resin composition on a substrate, first heating the coated photosensitive resin composition to a temperature of 75 °C to 85 °C, the coated photosensitive resin Exposing and developing the composition, and a step of secondary heating the developed photosensitive resin composition to a temperature of 80 °C to 90 °C, wherein the photosensitive resin composition is a radical photoinitiator based on 100 parts by weight of the acrylic copolymer 0.1 to 20 parts by weight, 0.1 to 10 parts by weight of an ionic photoinitiator, 1 to 50 parts by weight of a polyfunctional acrylate oligomer, 1 to 50 parts by weight of a polyfunctional monomer having an ethylenically unsaturated bond, and a solvent.

The gas in the photosensitive resin composition may be removed through the primary heating, and the photosensitive resin composition may be cured through the secondary heating.

The first heating may be performed for 1 to 5 minutes.

The secondary heating may be performed for 30 minutes to 240 minutes.

The radical photoinitiator is 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione or 2-(O-acetyloxime)-1-[4-(phenylthio) phenyl]-1,2-octanedione.

The ionic photoinitiator is phenyl (4-methoxyphenyl) iodonium hexafluoride, N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid, 4-methylphenyl (4- (2-methylpropylphenyl)) iodonium hexafluoride And it may be at least one selected from the group consisting of phenyl (4-methoxyphenyl) iodonium arsenic hexafluoride.

The content ratio of the radical photoinitiator and the ionic photoinitiator may be 2:1 to 1:2.

The photosensitive resin composition may have a solid content of 10 wt% to 50 wt%.

The photosensitive resin composition may further include a melamine crosslinking agent.

The photosensitive resin composition may further include a silane coupling agent.

According to the embodiments, the photosensitive resin composition and the pattern forming method using the same according to the present embodiment have excellent sensitivity and film remaining rate and improved residue properties. It has excellent adhesion and chemical resistance in low-temperature processes.

1 to 4 are process flow diagrams illustrating a pattern forming method according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, various embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. The present invention may be embodied in several different forms and is not limited to the embodiments described herein.

In order to clearly explain the present invention, parts irrelevant to the description are omitted, and the same reference numerals are assigned to the same or similar components throughout the specification.

In addition, since the size and thickness of each component shown in the drawings are arbitrarily indicated for convenience of description, the present invention is not necessarily limited to the illustrated bar. In order to clearly express various layers and regions in the drawings, the thicknesses are enlarged. And in the drawings, for convenience of description, the thickness of some layers and regions are exaggerated.

Further, when a part of a layer, film, region, plate, etc. is said to be “on” or “on” another part, it includes not only cases where it is “directly on” another part, but also cases where another part is in between. . Conversely, when we say that a part is "just above" another part, we mean that there is no other part in the middle. In addition, to be "on" or "on" the reference part is located above or below the reference part, and does not necessarily mean to be located "on" or "on" the opposite direction of gravity. .

In addition, throughout the specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

Then, first, a photosensitive resin composition according to an embodiment of the present invention will be described. The photosensitive resin composition according to an embodiment of the present invention contains 0.1 to 20 parts by weight of a radical photoinitiator, 0.1 to 10 parts by weight of an ionic photoinitiator, 1 to 50 parts by weight of a polyfunctional acrylate oligomer, and 1 to 50 parts by weight of an ethylenically unsaturated based on 100 parts by weight of the acrylic copolymer. 1 to 50 parts by weight of a polyfunctional monomer having a bond, and a solvent.

That is, the photosensitive resin composition according to an embodiment of the present invention includes a radical photoinitiator and an ionic photoinitiator at the same time. Therefore, it can be cured even at a low temperature of 90°C or less, and exhibits excellent adhesion and chemical resistance even when cured at a temperature of 90°C or less. The photosensitive resin composition according to the present embodiment is a negative photosensitive resin composition in which the exposed portion is cured and the unexposed portion is removed.

Usually, a temperature of 200°C or higher is required for curing of the photosensitive resin composition. However, when the photosensitive resin composition is applied as an insulating film of a touch panel integrated with a display device, the characteristics of the light emitting layer included in the display device may change at a high temperature of 200 °C or higher required for curing of the photosensitive resin composition. Therefore, the photosensitive resin composition cured at a high temperature of 200 °C or higher cannot be applied to an insulating film formed by a continuous process with the light emitting layer, and a process of laminating the insulating film after manufacturing it by a separate process is required.

However, since the photosensitive resin composition according to the present embodiment contains a radical photoinitiator and an ionic photoinitiator at the same time, it is cured even at a low temperature of 90 °C or less, and thus can be used as an insulating film manufactured in a continuous process with the light emitting layer. Accordingly, it is possible to reduce the number of masks in the manufacturing process.

In addition, since the insulating film made of the photosensitive composition of the present embodiment is an organic film, it is more suitable for application to a flexible display device than an insulating film including an existing inorganic material. In addition, chemical vapor deposition (CVD), dry etching, strip process, etc. required in the manufacturing process of an insulating film including an existing inorganic material can be omitted.

The reason that the photosensitive resin composition of the present invention can be cured at a temperature of 90 °C or less is because it contains a radical photoinitiator and an ionic photoinitiator at the same time. That is, in order for the curing reaction to occur, the bond of the ring must be broken and the ring structure must be opened. Both the radical photoinitiator and the ionic photoinitiator serve to break the ring, increasing the reaction site and allowing the reaction to occur actively even at a lower temperature. .

In this case, the content ratio of the radical photoinitiator and the ionic photoinitiator may be approximately 2:1 to 1:2. This is a numerical range capable of maximizing the adhesive strength and chemical resistance of the cured photosensitive resin composition during low-temperature curing.

In the photosensitive resin composition according to an embodiment of the present invention, the acrylic copolymer prevents residues from being generated during development, so that a pattern can be easily formed.

The acrylic copolymer may be formed by copolymerizing an unsaturated carboxy compound and an unsaturated olefin compound. Specifically, the acrylic copolymer is synthesized by radical reaction in the presence of a solvent and a polymerization initiator using i) unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, or a mixture thereof, ii) using an olefinically unsaturated compound as a monomer, followed by precipitation and filtration , it can be obtained by removing unreacted monomers through a vacuum drying process.

The unsaturated carboxylic acid, unsaturated carboxylic acid anhydride or mixtures thereof used in the present invention include unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, metaconic acid, and itaconic acid; Or the anhydride of these unsaturated dicarboxylic acids, etc. can be used individually or in mixture of 2 or more types. In particular, acrylic acid, methacrylic acid, or maleic acid is preferable because it is excellent in copolymerization reactivity and solubility in an aqueous alkali solution as a developer.

The unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, or a mixture thereof is preferably included in an amount of 5 to 40 parts by weight based on 100 parts by weight of the total total monomers. When the content is less than 5 parts by weight, there is a problem that it is difficult to dissolve in an aqueous alkali solution, and when it exceeds 40 parts by weight, there is a problem that solubility in an aqueous alkali solution becomes too large.

The olefinically unsaturated compound used in the present invention is methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, methyl acrylate, isopropyl acrylate , cyclohexyl methacrylate, 2-methylcyclohexyl methacrylate, dicyclopentenyl acrylate, dicyclopentanyl acrylate, dicyclopentenyl methacrylate, dicyclopentanyl methacrylate, 1-adamantyl acrylic Late, 1-adamantyl methacrylate, dicyclopentanyloxyethyl methacrylate, isoboronyl methacrylate, cyclohexyl acrylate, 2-methylcyclohexyl acrylate, dicyclopentanyloxyethyl acrylate, iso Boronyl acrylate, phenyl methacrylate, phenyl acrylate, benzyl acrylate, 2-hydroxyethyl methacrylate, styrene, σ-methyl styrene, m-methyl styrene, p-methyl styrene, vinyltoluene, p- Methoxy styrene, 1,3-butadiene, isoprene, or 2,3-dimethyl 1,3-butadiene, glycidyl acrylate, glycidyl methacrylate, α-ethyl acrylate glycidyl, α-n-propyl acrylic acid Glycidyl, α-n-butylacrylic acid glycidyl, acrylic acid-β-methylglycidyl, methacrylic acid-β-methylglycidyl, acrylic acid-β-ethylglycidyl, methacrylic acid-β-ethyl Glycidyl, acrylic acid-3,4-epoxybutyl, methacrylic acid-3,4-epoxybutyl, acrylic acid-6,7-epoxyheptyl, methacrylic acid-6,7-epoxyheptyl, α-ethylacrylic acid-6 ,7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, and p-vinylbenzyl glycidyl ether, selected from the group consisting of 3,4-epoxy cyclohexyl methacrylic acid One or more may be used, and the above compounds may be used alone or in combination of two or more.

The olefinically unsaturated compound is preferably included in an amount of 60 to 95 parts by weight based on 100 parts by weight of the total total monomers. When the content is less than 60 parts by weight, there is a problem in that resolution and heat resistance are lowered, and when it exceeds 95 parts by weight, there is a problem in that the acrylic copolymer is difficult to dissolve in an aqueous alkali solution as a developer.

A monomer including an epoxy group may be used as the olefinically unsaturated compound. These monomers can further increase heat resistance, chemical resistance, and physical properties by forming a dense structure by undergoing a crosslinking reaction by an ionic photoinitiator in the low temperature curing process.

The solvent used for solution polymerization of the above monomers may be methanol, tetrahydroxyfuran, toluene, dioxane, or the like.

The polymerization initiator used for solution polymerization of the above monomers may be a radical polymerization initiator, specifically 2,2-azobisisobutyronitrile, 2,2-azobis(2,4-dimethylvaleronitrile). ), 2,2-azobis(4-methoxy 2,4-dimethylvaleronitrile), 1,1-azobis(cyclohexane-1-carbonitrile), or dimethyl 2,2'-azobisisobutyl rate and the like can be used.

An acrylic copolymer is prepared by radically reacting the above monomers in the presence of a solvent and a polymerization initiator, and removing unreacted monomers through precipitation, filtration, and vacuum drying processes. The acrylic copolymer may have a polystyrene reduced weight average molecular weight (Mw) of 3,000 to 30,000. If the polystyrene conversion weight average molecular weight is less than 3,000, developability and residual film rate may decrease, or pattern development and heat resistance may decrease, and if it exceeds 30,000, pattern development may deteriorate.

The photoinitiator used in the photosensitive resin composition of the present invention includes at least one radical photoinitiator and at least one ionic photoinitiator, respectively.

The radical photoinitiator includes 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, diethoxyacetophenone, p-dimethylaninoacetophenone, 1-(4-isopropylphenyl)-2-hydroxy -2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl- 2-Dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morphol) acetophenone compounds such as nyl)phenyl]-1-butanone, benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzyl dimethyl ketal; benzophenone, benzoylbenzoic acid; Methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3',4,4'-tetra(t-butylperoxycarbonyl) ) Benzophenone-based compounds such as benzophenone, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, isopropylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-di Thioxanthone-based compounds such as ethyl thioxanthone, 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p- Methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-pipenonyl- 4,6-bis(trichloromethyl)-s-triazine, 2,4-bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphtho-1-yl)-4, 6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4- Triazine-based compounds such as trichloromethyl-(piperonyl)-6-triazine and 2,4-trichloromethyl(4'-methoxystyryl)-6-triazine, 2-(O-benzoyloxime) -1-[4-(phenylthio)phenyl]-1,2-octanedione, 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole -3-yl]-ethanone, O-ethoxycarbonyl-α-oxyamino-1-phenylpropan-1-one, 1,2-octanedione, 2-dimethylamino-2-(4-methylbenzyl) -1-(4-morpholin-4-yl-phenyl)-butan-1-one, 1-(4-phenylsulfanylphenyl)-butane-1,2-dione-2-oxime-O-benzoate; 1-(4-phenylsulfanylphenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylsulfanylphenyl)-octane-1-oneoxime-O-acetate; 1-(4-phenylsulfanylphenyl)-butan-1-oneoxime-O-acetate, 2-(O-benzoyloxime)-1-[4-(phenylthio)p-methylphenyl]-1,2-octane Dione, 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-phenyldione, 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl] -1,2-octanedione, 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl]-1,2-phenyldione, 2-(O-acetyloxime)-1-[4- (phenylthio)phenyl]-1,2-methyldione, O-(acetyl)-N-(1-phenyl-2-oxo-2-(4'-methoxy-naphthyl)ethylidene)hydroxylamine, etc. of oxime ester compounds, phosphine compounds such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, o-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(o-methoxyphenyl)-4,4',5,5 imidazole compounds such as '-tetraphenylbiimidazole, 2,2'-bis(o-methoxyphenyl)-4,4',5,5'-tetra(p-methylphenyl)biimidazole, 9, Quinone compounds such as 10-phenanthrenequinone, camphorquinone, and ethylanthraquinone, borate compounds, carbazole compounds, titanocene compounds, etc. may be used, and these may be used alone or in combination of two or more.

The content of the radical photoinitiator is preferably contained in an amount of 0.1 to 20 parts by weight of the radical photoinitiator based on 100 parts by weight of the acrylic copolymer. When the content of the radical photoinitiator is less than 0.1 parts by weight, the residual film rate is deteriorated due to low sensitivity, and when it exceeds 20 parts by weight, developability and resolution are deteriorated.

The ionic photoinitiator may include a cationic photoinitiator and an anionic photoinitiator. Cationic photoinitiators include sulfonium salts, iodonium salts, phosphonium salts, diazonium salts, pyridinium salts, benzothiazolium salts, sulfoxonium salts, and ferrocene compounds as onium salts, and other nitrobenzylsulfonates, alkyl or allyl-N-sulfonyloxyimides, halogenated alkylsulfonic acid esters, oxime sulfonates, and the like, but are not limited thereto.

In one example, cationic photoinitiators include tetrabutylammoniumtetrafluoroborate, tetrabutylammoniumhexafluorophosphate, tetrabutylammoniumhydrogensulfate, tetraethylammoniumtetrafluoroborate, tetraethylammonium, p-toluenesulfonate, N,N -Dimethyl-N-benzylanilinium antimony hexafluoride, N,N-dimethyl-N-benzylanilinium boron tetrafluoride, N,N-dimethyl-N-benzylpyridinium antimony hexafluoride, N,N-dimethyl-N- Benzyltrifluoromethanesulfonic acid, N,N-dimethyl-N-(4-methoxybenzyl)pyridinium antimony hexafluoride, N,N-dimethyl-N-(4-methoxybenzyl)toluidinium hexafluoride antimony; Ethyltriphenylphosphonium antimony hexafluoride, tetrabutylphosphonium antimony hexafluoride, triphenylsulfonium boron tetrafluoride, triphenylsulfonium antimony hexafluoride, triphenylsulfonium arsenic hexafluoride, tri(4-methoxyphenyl)sulfonium arsenic hexafluoride , Diphenyl (4-phenylthiophenyl) sulfonium arsenic hexafluoride, diphenyl iodonium arsenic hexafluoride, di-4-chlorophenyl iodonium arsenic hexafluoride, di-4-bromphenyl iodonium arsenic hexafluoride, phenyl (4-methoxy Phenyl) iodonium arsenic hexafluoride, diphenyl iodonium hexafluoride, di-4-chlorophenyl iodonium hexafluoride, di-4-bromphenyl iodonium hexafluoride, phenyl (4-methoxyphenyl) iodonium hexafluoride, 4 -Methylphenyl (4-(2-methylpropylphenyl)) iodonium hexafluoride, di-4-tetraphenyl iodonium hexafluoride, diphenyl iodonium hexafluoride, di-4-tetraphenyl iodonium hexafluoride antimony hexafluoride, diphenyl iodine It may be one or more selected from the group consisting of antimony nium hexafluoride, 4-methylphenyl(4-(2-methylpropylphenyl))iodonium arsenic tetrafluoride, but is not limited thereto.

The anionic photoinitiator may be at least one selected from the group consisting of benzoincarbamate, dimethylbenzyloxycarbamoylamine, o-acyloxime, o-nitrobenzoincarbamate, formanilide derivatives, and α-ammoniumacetophenone, but is limited thereto. it is not going to be

The content of the ionic photoinitiator may be 0.1 to 10 parts by weight based on 100 parts by weight of the acrylic copolymer. When the ionic photoinitiator content is less than 0.1 parts by weight, chemical resistance is deteriorated due to a low degree of curing, and when it exceeds 10 parts by weight, a residue is generated due to an excessive degree of curing, and resolution may be reduced.

The polyfunctional acrylate oligomer included in the photosensitive resin composition according to this embodiment has 2 to 20 functional groups. For example, aliphatic urethane acrylate oligomer, aromatic urethane acrylate oligomer, epoxy acrylate oligomer, epoxy methacrylate oligomer, polyester acrylate oligomer, silicone acrylate oligomer, melamine acrylate oligomer, dendritic acrylate oligomer, etc. may be used, and these may be used alone or in combination of two or more.

The content of the polyfunctional acrylate oligomer is preferably 1 to 50 parts by weight based on 100 parts by weight of the acrylic copolymer. When the content of the polyfunctional acrylate oligomer is less than 1 part by weight, there is a problem in that the residual film ratio is deteriorated due to low sensitivity, and when it exceeds 50 parts by weight, developability may be deteriorated and resolution may be deteriorated.

In addition, the polyfunctional monomer having an ethylenically unsaturated bond included in the photosensitive resin composition according to an embodiment of the present invention is 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacryl Late, trimethylol propane diacrylate, trimethylol propane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexadiacrylate, di Pentaerythritol tridiacrylate, dipentaerythritol diacrylate, sorbitol triacrylate, bisphenol A diacrylate derivative, dipentaerythritol polyacrylate, and their methacrylate may be used alone or in combination It can be used by mixing more than one species.

The content of the polyfunctional monomer having an ethylenically unsaturated bond may be 1 to 50 parts by weight based on 100 parts by weight of the acrylic copolymer. When the content is less than 1 part by weight, the residual film rate is deteriorated due to low sensitivity, and when it exceeds 50 parts by weight, developability may be deteriorated and resolution may be deteriorated.

The solvent used in the photosensitive resin composition according to an embodiment of the present invention is not limited, but for example, the boiling point may be less than 150 °C. When a solvent having a boiling point of less than 150 °C is used in this way, the residual solvent in the low-temperature process can be minimized and chemical resistance can be secured.

For example, the solvent is esters such as methyl-2-hydroxyisobutyrate, ethylene glycol methyl ether acetate, 2-methoxy-1-methylethyl ester, propylene acetate, ethyl propionate, ethyl pyruvate, 1-methyl Soluble from the group consisting of ethers such as oxy-2-propanol, dibutyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, tetrahydrofuran, and alcohols such as methanol, ethanol and isopropyl alcohol. , it is preferable to select and use one or more in consideration of the reactivity with each component and the ease of forming a coating film

The solvent is preferably included so that the solid content is 10 to 50% by weight in the total photosensitive resin composition. The composition having a solid content in the above range can be used after filtration through a Millipore filter of 0.1 to 0.2 μm or the like. In addition, as an example, the content of the solvent in the photosensitive resin composition may be in a range such that the solid content is 15 to 40 wt%.

When the solid content of the photosensitive resin composition is less than 10% by weight, the coating thickness becomes thin and there is a problem that the coating flatness is deteriorated. , and residual solvent may increase.

In addition, the photosensitive composition according to the present embodiment may further include a melamine crosslinking agent. The melamine crosslinking agent improves the heat resistance, chemical resistance and adhesion of the photosensitive composition.

As the melamine crosslinking agent, a condensation product of urea and formaldehyde, a condensation product of melamine and formaldehyde, or methylol urea alkyl ethers or methylol melamine alkyl ethers obtained from alcohol may be used.

Specifically, as the condensation product of urea and formaldehyde, monomethylol urea, dimethylol urea, and the like may be used. As the condensation product of melamine and formaldehyde, hexamethylolmelamine may be used, and in addition, a partial condensation product of melamine and formaldehyde may be used.

In addition, the methylol urea alkyl ethers are obtained by reacting a part or all of the methylol groups with alcohols in the condensation product of urea and formaldehyde, and specific examples thereof include monomethyl urea methyl ether and dimethyl urea methyl ether. can The methylol melamine alkyl ethers are those obtained by reacting a part or all of methylol groups with alcohols in a condensation product of melamine and formaldehyde, and specific examples thereof include hexamethylol melamine hexamethyl ether, hexamethylol melamine hexabutyl ether. etc. can be used. In addition, compounds having a structure in which the hydrogen atom of the amino group of melamine is substituted with a hydroxymethyl group and a methoxymethyl group, a compound having a structure in which the hydrogen atom of the amino group of melamine is substituted with a butoxymethyl group and a methoxymethyl group, etc. can also be used, especially methylolmelamine It is preferable to use alkyl ethers.

The content of the melamine crosslinking agent may be 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic copolymer.

In addition, the photosensitive composition according to the present embodiment may further include a silane coupling agent. The silane coupling agent improves adhesion of the photosensitive composition to the underlying substrate. The silane coupling agent is (3-glycidoxypropyl) trimethoxysilane, (3-glycidoxypropyl) triethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, (3-glycidoxypropyl) Glycideoxypropyl)methyldiethoxysilane, (3-glycidoxypropyl)dimethylethoxysilane, 3,4-epoxybutyltrimethoxysilane, 3,4-epoxybutyltriethoxysilane, 2 -(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, aminopropyltrimethoxysilane, aminopropyltriethoxy Silane, 3-triethoxysilly-N-(1,3 dimethyl-butylidene)propylamine, N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3 -Aminopropyltriethoxysilane, N-2(aminoethyl)3-aminopropylmethyldimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane or (3-isocyanatepropyl)triethoxysilane Phosphorus and the like may be used alone or in combination of two or more.

The silane coupling agent may be included in an amount of 0.1 to 20 parts by weight based on 100 parts by weight of the acrylic copolymer.

In addition, the photosensitive resin composition according to an embodiment of the present invention may further include a surfactant. Such a surfactant can improve the applicability and developability of the photosensitive resin composition. Such surfactants include silicone-based and fluorine-based surfactants. The surfactant may be included in an amount of 0.0001 to 2 parts by weight based on 100 parts by weight of the solid content in the photosensitive resin composition.

Then, a pattern forming method using the photosensitive resin composition according to an embodiment of the present invention will be described below. The photosensitive resin composition according to an embodiment of the present invention comprises the steps of coating the photosensitive resin composition on a substrate, first heating the photosensitive resin composition to a temperature of 75 °C to 85 °C, exposing the photosensitive resin composition and Developing, comprising the step of heating the developed photosensitive resin composition to a temperature of 80 °C to 90 °C secondary. The photosensitive resin composition used at this time is the same as the photosensitive resin composition described above. Duplicate descriptions of the same components will be omitted.

1 to 4 are process flow diagrams illustrating a pattern forming method according to an embodiment of the present invention.

Referring to FIG. 1 , first, a photosensitive resin composition 400 is coated on a substrate 110 to form a photosensitive resin composition coating layer 400 . In this case, the coating may be performed by a spray method, a roll coater method, a rotation coating method, or the like.

In this case, the photosensitive resin composition contains 0.1 to 20 parts by weight of a radical photoinitiator, 0.1 to 10 parts by weight of an ionic photoinitiator, 1 to 50 parts by weight of a polyfunctional acrylate oligomer, and 1 to 50 parts by weight of a polyfunctional monomer having an ethylenically unsaturated bond with respect to 100 parts by weight of the acrylic copolymer. to 50 parts by weight, and a solvent. Since this photosensitive resin composition contains a radical photoinitiator and an ionic photoinitiator at the same time, it can be cured at a low temperature of 90 °C or less, and exhibits excellent adhesion and chemical resistance even when cured at a low temperature of 90 °C or less. The photosensitive resin composition is a negative photosensitive resin composition in which the exposed portion is cured and remains.

Next, referring to FIG. 2 , the coated photosensitive resin composition 400 is first heated to a temperature of 75°C to 85°C. This is a pre-bake process, and the gas contained in the photosensitive resin composition 400 coated through this process is removed. The first heating may be performed for about 1 to 5 minutes. In this case, since the photosensitive resin composition of the present invention uses a solvent having a low boiling point of less than 150 °C, gas and the like contained in the solvent can be better removed.

Next, referring to FIG. 3 , the photosensitive resin composition layer 410 is formed by exposing and developing the coated photosensitive resin composition. The photosensitive resin composition according to an embodiment of the present invention is a negative photosensitive resin composition, and a portion corresponding to the opening of the mask 700 , that is, an exposed portion remains cured and an unexposed portion is removed. In this case, the exposure may be performed using visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray, or the like. The development uses a developer, and the unexposed part is removed.

It is preferable to use an aqueous alkali solution as the developer, and specifically, inorganic alkalis such as sodium hydroxide, potassium hydroxide, and sodium carbonate; primary amines such as n-propylamine; secondary amines such as diethylamine and n-propylamine; tertiary amines such as trimethylamine, methyldiethylamine, dimethylethylamine, and triethylamine; alcohol amines such as dimethylethanolamine, methyldiethanolamine, and triethanolamine; Alternatively, an aqueous solution of a quaternary ammonium salt such as tetramethylammonium hydroxide or tetraethylammonium hydroxide can be used. In this case, the developer is used by dissolving the alkaline compound at a concentration of 0.1 to 10 wt%, and an appropriate amount of a water-soluble organic solvent such as methanol or ethanol and a surfactant may be added.

Next, referring to FIG. 4 , the photosensitive resin composition layer 410 is secondarily heated to a temperature of about 80°C to 90°C. The secondary heating is a process of curing the photosensitive resin composition layer 410 . This secondary heating may be performed for about 30 minutes to 240 minutes. Since the photosensitive resin composition according to an embodiment of the present invention is cured even at a temperature of 90 °C or less, an insulating film, etc. can be manufactured without damage to the light emitting layer even when the light emitting layer is located under the photosensitive resin composition.

That is, the photosensitive resin composition of the present invention and a pattern forming method using the same are passivation insulating film, gate insulating film, planarization film, column spacer, overcoat or It can be used as a color resist. At this time, since the photosensitive resin composition is cured by a low-temperature process, it can be manufactured in a single process on the upper part of the structure including the light emitting layer, and the process can be simplified.

In addition, the structure of a manufactured display device may be simplified. For example, through the pattern forming method using the photosensitive resin composition according to the present embodiment, a display device having a structure in which a touch panel is embedded on an organic light emitting element may be manufactured. That is, the touch sensing electrode may be formed directly on the thin film encapsulation layer on the organic light emitting device, and the photosensitive resin composition according to the present embodiment may be used as an insulating film positioned between the touch sensing electrodes. In the case of such a structure, when the temperature exceeds 100 °C in the process of manufacturing the insulating film, the light emitting layer of the organic light emitting device is damaged, which is not preferable. However, in the photosensitive resin composition and the pattern forming method using the same according to the present embodiment, since the photosensitive resin composition is cured at a temperature of 90°C or less, an insulating film or the like can be manufactured without damaging the lower emission layer.

Then, the effect of the photosensitive resin composition and the pattern forming method using the photosensitive resin composition according to an embodiment of the present invention will be described below through specific experimental examples.

Synthesis example 1: (Production of acrylic copolymer)

A mixed solution of 400 parts by weight of tetrahydrofuran, 30 parts by weight of methacrylic acid and 30 parts by weight of styrene, and 40 parts by weight of glycidyl methacrylate was added to a flask equipped with a cooler and a stirrer. After sufficiently mixing the liquid composition at 600 rpm in a mixing vessel, 15 parts by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) was added. The polymerization mixture solution was slowly raised to 55, maintained at this temperature for 24 hours, cooled to room temperature, and 500 ppm of hydrobenzophenone was added as a polymerization inhibitor to obtain a polymer solution having a solid content of 30 wt%.

In order to remove unreacted monomers from the polymer solution, 100 parts by weight of the polymer solution was precipitated with respect to 1000 parts by weight of n-hexane. After precipitation, a solvent in which unreacted substances were dissolved was removed through a filtering process using a mesh. After that, in order to remove the solvent containing the unreacted monomer remaining after the filtering process, the solvent containing the unreacted monomer was completely removed through vacuum drying at 30 degrees or less to prepare an acrylic copolymer.

The weight average molecular weight of the acrylic copolymer was 6,000. In this case, the weight average molecular weight is the polystyrene reduced average molecular weight measured using GPC.

Example One: negative Preparation of photosensitive resin composition

100 parts by weight of the acrylic copolymer solution prepared in Synthesis Example 1, 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione as a radical photoinitiator, 10 parts by weight, ions 10 parts by weight of phenyl (4-methoxyphenyl) iodonium hexafluoride as a photoinitiator, 10 parts by weight of a 10-functional urethane acrylate oligomer, 20 parts by weight of dipentaerythritol hexaacrylate as a polyfunctional monomer having an ethylenically unsaturated bond, and a melamine crosslinking agent 3 parts by weight of raw hexamethylolmelamine hexamethyl ether and 2 parts by weight of (3-glycidoxypropyl)methyldiethoxysilane as a silane coupling agent were mixed. Propylene glycol monoethyl acetate was added and dissolved to the mixture so that the solid content concentration was 20 wt%, and then filtered through a 0.2 μm Millipore filter to prepare a coating solution for a negative photosensitive resin composition.

Example 2: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that ethylene glycol methyl ether acetate was used as a solvent in Example 1.

Example 3 : negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid was used as the ion photoinitiator in Example 1.

Example 4: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that 4-methylphenyl(4-(2-methylpropylphenyl))iodonium hexafluoride was used as the ionic photoinitiator in Example 1.

Example 5: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that phenyl (4-methoxyphenyl) iodonium arsenic hexafluoride was used as the ion photoinitiator in Example 1.

comparative example One: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that 0.05 parts by weight of the ionic photoinitiator was used in Example 1.

comparative example 2: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that 25 parts by weight of the ionic photoinitiator was used in Example 1.

comparative example 3: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that the ionic photoinitiator was completely removed in Example 1.

comparative example 4: negative Preparation of photosensitive resin composition

Photosensitivity was performed in the same manner as in Comparative Example 3, except that 2-(O-acetyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione was used as a radical photoinitiator in Comparative Example 3 A resin composition coating solution was prepared.

comparative example 5: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that ethyl lactate was used as a solvent in Example 1.

comparative example 6: negative Preparation of photosensitive resin composition

A photosensitive resin composition coating solution was prepared in the same manner as in Example 1, except that propylene glycol monomethyl propionate was used as a solvent in Example 1.

After evaluating the physical properties in the same manner as in Experimental Examples 1 to 5 below using the coating solutions of the negative photosensitive resin composition prepared in Examples 1 to 5 and Comparative Examples 1 to 6, the results are shown in Table 1 below. it was

Experimental example 1: Sensitivity, remaining film rate measurement

After applying the negative photosensitive composition solutions prepared in Examples 1 to 5 and Comparative Examples 1 to 6 using a spin coater on a glass substrate on which SiN _{x was deposited, the solution was pre-freed on a hot plate at 80° C. for 2 minutes.} It was baked to form a 2.0 mu m film. Using a predetermined pattern mask, the film obtained above was irradiated with ultraviolet rays having an intensity of 10 mW/cm 2 at 365 nm using a broadband exposure machine at 0.2 second intervals for 1 to 5 seconds. Thereafter, development was performed at 23° C. for 60 seconds with an aqueous solution of 2.38 wt% of tetramethyl ammonium hydroxide, followed by washing with ultrapure water for 60 seconds.

For final curing, a patterned film was obtained by heating in an oven at 85° C. for 60 minutes. Sensitivity was measured based on the exposure amount at which the residual film rate was saturated based on 20 μm Line & Space CD using SEM.

Experimental example 2: remaining film rate

When measuring the sensitivity of Experimental Example 1, it was confirmed that the remaining film ratio was sensitive to saturation (Saturation). At this time, if the residual film rate was 80% or more, it was indicated by ○, if it was 80% to 75%, △, and if it was 75% or less, it was indicated by X.

Experimental example 3: residue

Scum was inspected based on the contact hole of the pattern film formed during the sensitivity measurement of Experimental Example 1. At this time, the case where there was no residue was denoted by ○, and the case where the residue was observed was denoted by X.

Experimental example 4: Adhesion

A case in which peel-off of the formed pattern film did not occur during the sensitivity measurement of Experimental Example 1 was denoted by ○, and a case in which peel-off occurred was denoted by X.

Experimental example 5: Chemical resistance

The pattern film formed during the sensitivity measurement of Experimental Example 1 was put in a stripper and left to stand, and then the thickness change was measured. At this time, the case where the thickness change was 0.5 μm or less was denoted by ○, the case where the thickness was 0.5 μm to 1.0 μm was denoted by △, and the case where the thickness change was 1.0 μm or more was denoted by X.

Sensitivity
(mJ/cm2) remaining film rate residue adhesion chemical resistance Example 1 40 ○ ○ ○ ○ Example 2 40 ○ ○ ○ ○ Example 3 45 ○ ○ ○ ○ Example 4 40 ○ ○ ○ ○ Example 5 35 ○ ○ ○ ○ Comparative Example 1 50 △ ○ X △ Comparative Example 2 37 ○ X ○ ○ Comparative Example 3 50 X ○ X X Comparative Example 4 45 △ X X △ Comparative Example 5 50 X ○ X △ Comparative Example 6 52 X ○ X X

As can be seen from Table 1, Examples 1 to 5 containing an ionic photoinitiator and a low boiling point solvent according to an embodiment of the present invention have sensitivity, residual film rate, residue, adhesion, chemical resistance compared to Comparative Examples 3 to 6 This excellence was confirmed.

In addition, when comparing Comparative Examples 1 and 2, in which the content range of the ionic photoinitiator is not included between 0.1 to 10 parts by weight, and Example 1, the content range of the ionic photoinitiator should be included in 0,1 to 10 parts by weight. It was confirmed that uniform performance was exhibited in the remaining film ratio, residue, and adhesive force. That is, Comparative Example 1, in which the content of the ionic photoinitiator was 0.05 parts by weight, had poor film retention and adhesion, and Comparative Example 2, in which the content of the ionic photoinitiator was 25 parts by weight, had poor residue.

That is, as described above, the photosensitive resin composition according to an embodiment of the present invention including the radical photoinitiator and the ionic photoinitiator at the same time has excellent sensitivity, film remaining rate, residue, etc. It was confirmed that it was excellent and suitable for use in a flexible display.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements by those skilled in the art using the basic concept of the present invention as defined in the following claims are also provided. is within the scope of the right.

110: substrate
400: coated photosensitive resin composition
410: photosensitive resin composition layer
700: mask

Claims (22)

Based on 100 parts by weight of the acrylic copolymer
0.1 to 20 parts by weight of a radical photoinitiator;
0.1 to 10 parts by weight of an ionic photoinitiator;
1 to 50 parts by weight of polyfunctional acrylate oligomer;
1 to 50 parts by weight of a polyfunctional monomer having an ethylenically unsaturated bond, and
containing a solvent;
The polyfunctional monomer having an ethylenically unsaturated bond is 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, trimethylol propane diacrylate, trimethylol propane triacrylate , pentaerythritol triacrylate, pentaerythritol tetraacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexadiacrylate, dipentaerythritol tridiacrylate, dipentaerythritol diacrylate, sorbitol A photosensitive resin composition comprising at least one selected from triacrylate, bisphenol A diacrylate derivative, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, and methacrylates thereof,
The photosensitive resin composition is a photosensitive resin composition that is cured at a temperature of 90 °C or less.
delete In claim 1,
The radical photoinitiator is 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione or 2-(O-acetyloxime)-1-[4-(phenylthio) A photosensitive resin composition which is phenyl]-1,2-octanedione. In claim 1,
The ionic photoinitiator is phenyl (4-methoxyphenyl) iodonium hexafluoride, N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid, 4-methylphenyl (4- (2-methylpropylphenyl)) iodonium hexafluoride , And phenyl (4-methoxyphenyl) iodonium arsenic hexafluoride at least one photosensitive resin composition selected from the group consisting of. In claim 1,
The content ratio of the radical photoinitiator and the ionic photoinitiator is 2:1 to 1:2 of the photosensitive resin composition. In claim 1,
The photosensitive resin composition having a solid content of 10% to 50% by weight of the photosensitive resin composition. In claim 1,
The photosensitive resin composition further comprising a melamine crosslinking agent. In claim 1,
The photosensitive resin composition further comprising a silane coupling agent. In claim 1,
The acrylic copolymer is a photosensitive resin composition formed by copolymerizing an unsaturated carboxy compound and an unsaturated olefin compound. In claim 1,
The solvent is a photosensitive resin composition having a boiling point of less than 150 °C. coating the photosensitive resin composition on the substrate;
First heating the coated photosensitive resin composition to a temperature of 75 ° C to 85 ° C;
exposing and developing the coated photosensitive resin composition; and
Comprising the step of heating the developed photosensitive resin composition to a temperature of 80 ° C to 90 ° C,
The photosensitive resin composition is
Based on 100 parts by weight of the acrylic copolymer
0.1 to 20 parts by weight of a radical photoinitiator;
0.1 to 10 parts by weight of an ionic photoinitiator;
1 to 50 parts by weight of polyfunctional acrylate oligomer;
1 to 50 parts by weight of a polyfunctional monomer having an ethylenically unsaturated bond, and
containing a solvent;
The polyfunctional monomer having an ethylenically unsaturated bond is 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, ethylene glycol diacrylate, trimethylol propane diacrylate, trimethylol propane triacrylate , pentaerythritol triacrylate, pentaerythritol tetraacrylate, triethylene glycol diacrylate, polyethylene glycol diacrylate, dipentaerythritol hexadiacrylate, dipentaerythritol tridiacrylate, dipentaerythritol diacrylate, sorbitol A method of forming a pattern at least one selected from triacrylate, bisphenol A diacrylate derivative, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, and methacrylates thereof. In claim 11,
Gas in the photosensitive resin composition is removed through the primary heating,
A pattern forming method in which the photosensitive resin composition is cured through the secondary heating. In claim 11,
The first heating is a pattern forming method that is performed for 1 to 5 minutes, In claim 11,
The second heating is a pattern forming method that is performed for 30 minutes to 240 minutes. In claim 11,
The radical photoinitiator is 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione or 2-(O-acetyloxime)-1-[4-(phenylthio) phenyl]-1,2-octanedione. In claim 11,
The ionic photoinitiator is phenyl (4-methoxyphenyl) iodonium hexafluoride, N,N-dimethyl-N-benzyltrifluoromethanesulfonic acid, 4-methylphenyl (4- (2-methylpropylphenyl)) iodonium hexafluoride and phenyl (4-methoxyphenyl) iodonium arsenic hexafluoride. At least one pattern forming method selected from the group consisting of. In claim 11,
The content ratio of the radical photoinitiator to the ionic photoinitiator is 2:1 to 1:2. In claim 11,
A pattern forming method wherein the photosensitive resin composition has a solid content of 10% to 50% by weight. In claim 11,
The photosensitive resin composition is a pattern forming method further comprising a melamine crosslinking agent. In claim 11,
The photosensitive resin composition is a pattern forming method further comprising a silane coupling agent.
In claim 1,
The content of the polyfunctional monomer having an ethylenically unsaturated bond is 20 to 50 parts by weight of the photosensitive resin composition. In claim 11,
The content of the polyfunctional monomer having an ethylenically unsaturated bond is 20 to 50 parts by weight of the pattern forming method.

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