WO2012044070A2

WO2012044070A2 - Photosensitive resin composition for organic insulator

Info

Publication number: WO2012044070A2
Application number: PCT/KR2011/007156
Authority: WO
Inventors: Yun Jae Lee; Chung Seock Kang; Pil Rye Yang; Kyung Keun Yoon
Original assignee: Kolon Industries, Inc.
Priority date: 2010-09-30
Filing date: 2011-09-28
Publication date: 2012-04-05
Also published as: WO2012044070A3; JP5699219B2; KR101427445B1; JP2013541733A; TW201214043A; TWI557502B; KR20120033895A

Abstract

Provided is a photosensitive resin composition capable of acquiring high flatness, sensitivity, heat resistance, transparency, and a low residual film ratio and significantly improving adhesion between substrates and particularly, minimizing loss of the film during a developing process by increasing crosslink density during an exposing process by introducing a silsesquioxane compound having a photosensitive functional group in order to minimize excessive loss of the film during the developing process in an organic insulator introducing a known silsesquioxane compound having an epoxy group, in which the photosensitive resin composition is suitable for being applied to the organic insulator in various display processes.

Description

PHOTOSENSITIVE RESIN COMPOSITION FOR ORGANIC INSULATOR

The present invention relates to a photosensitive resin composition suitable for an organic insulator in various display processes.

A thin film transistor liquid crystal display (TFT-LCD) bonds an organic substrate with a TFT-array with a glass substrate with a color filter so as to maintain a predetermined interval, injects a liquid crystal between two sheets of glass substrate to form a panel, and thereafter, applies an electric signal, thereby displaying images. However, since the LCD panel does not self-emit light, a separate light source capable of emitting the light is required and referred to as a bottom light source. It is important to achieve low consumption power and high luminance among TFT-LCD characteristics. A method of achieving the low consumption power may be classified into a driving circuit technology, a bottom light source technology, and a panel technology and a panel-related technology is required to improve transmitting efficiency of a polarizing plate, improve transmittance of a color filter, and increase an aperture ratio of the TFT-array, that is, an area transmitting light. The aperture ratio means a ratio of an open or transparent portion for the entire surface area. Recently, the result for the TFT-LCD focuses on improvement of a wide viewing angle and a pixel aperture ratio and in this case, a high aperture ratio implements the high luminance to reduce the consumption power of the bottom light source.

In some cases, a known organic insulator uses PVA (KR-A-2002-008427), polyimide (KR-A-2003-0016981), photoacryl (US-B-6,232,157), and the like, but there is a problem in that permittivity is high and an element characteristic enough to displace a known inorganic insulator is not shown.

The present invention has been made in an effort to provide a photosensitive resin composition having advantages of minimizing a loss of a pattern and a loss of a film during a developing process by increasing curing density during an exposing process as an organic insulator having excellent flatness, sensitivity, heat resistance, transparency, adhesion, and the like and low dielectric constant.

An exemplary embodiment of the present invention provides a photosensitive resin composition for an organic insulator, comprising: [A] an alkali-soluble resin, [B] a unsaturated ethylene-based monomer, [C] a silsesquioxane-based compound of the following Chemical Formula 1, [D] a photopolymerizable initiator, and [E] a solvent.

(Herein, R is an acryl group or an oxetal group, R1 is a C1-C5 alkyl group or a hydrogen atom, R₂ is a C1-C5 alkoxy group, a C1-C5 alkyl group, or a hydrogen atom, and m and n are 1 to 10 respectively.)

A molecular weight of the [C] silsesquioxane-based compound may be 1000 to 4000.

The [C] silsesquioxane-based compound may be bifunctional to trifunctional.

The content of the [C] silsesquioxane-based compound may be 5 wt% to 60 wt% with respect to the entire content of the composition.

The [A] alkali-soluble resin may be a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic acid anhydride; and [a2] an unsaturated compound containing an epoxy group.

The [A] alkali-soluble resin may be a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2]; a copolymer of one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3]; or a copolymer acquired by radical-polymerizing one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2], and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3].

The [a1] : [a2] component may be included by a weight ratio of 1:1.3 to 2.5.

The [a1] : [a2] component may be included by a weight ratio of 1:1.3 to 2.5 and the content of one or more compound selected from the [a3] and [a4] components may be 35 to 65 wt% with respect to the entire content of the [A] alkali-soluble resin.

The content of the [A] alkali-soluble resin may be 5 to 50 wt% with respect to the entire content of the composition.

The [A] alkali-soluble resin may have the solid content of 10 to 70 wt%.

The [B] unsaturated ethylene-based monomer may be an acryl monomer having two or more unsaturated ethylene bonds and the content thereof may be 5 to 60 wt% with respect to the entire content of the composition.

The dielectric constant after forming the thin film may be 3.3 or less.

The viscosity of the composition may be 3 to 30 cps.

Another exemplary embodiment of the present invention provides an organic insulator fabricated by using the composition.

Yet another exemplary embodiment of the present invention provides a display device including the organic insulator.

According to the exemplary embodiments of the present invention, since the photosensitive resin composition has excellent low permittivity, flatness, sensitivity, heat resistance, transparency, and adhesion without a pattern loss and an excessive film loss during a developing process to reduce consumption power, the photosensitive resin composition is suitable for an organic insulator in various display processes.

According to an exemplary embodiment of the present invention, a photosensitive resin composition for an organic insulator includes [A] an alkali-soluble resin, [B] a unsaturated ethylene-based monomer, [C] a silsesquioxane-based compound of the following Chemical Formula 1, [D] a photopolymerizable initiator, and [E] a solvent.

(Herein, R is an acryl group or an oxetal group, R₁ is a C1-C5 alkyl group or a hydrogen atom, R₂ is a C1-C5 alkoxy group, a C1-C5 alkyl group, or a hydrogen atom, and m and n are 1 to 10 respectively.)

Hereinafter, exemplary embodiments of the present invention will be described in more detail.

The photosensitive resin composition for an organic insulator according to an exemplary embodiment of the present invention includes:

[A] an alkali-soluble resin

([a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic acid anhydride;

[a2] a unsaturated compound containing an epoxy group;

[a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2]; and

[a4] an olefin-based unsaturated compound in addition to the [a1], [a2], and [a3],

among them, a copolymer of the [a1] and [a2] or a copolymer of one or more selected from the [a3] and [a4], the [a1], and the [a2], preferably, an alkali-soluble resin of the following Chemical Formula 2),

[B] a unsaturated ethylene-based monomer

[C] a silsesquioxane-based compound of the following Chemical Formula 1

[D] a photopolymerizable initiator

[E] a solvent.

Herein, R is an acryl group or an oxetal group, R₁ is a C1-C5 alkyl group or a hydrogen atom, R₂ is a C1-C5 alkoxy group, a C1-C5 alkyl group, or a hydrogen atom, and m and n are 1 to 10 respectively.

Herein, R₁ is a C1-C5 alkyl group or a hydrogen atom, R₂ is a C1-C5 alkyl group or a glycidyl group, Y is a C1-C5 alkyl group or a cycloalkyl group, Z is a C1-C5 alkyl group or a unsaturated group, and x, y, z and r are integers of more than 0, except for 0.

The photosensitive resin composition according to the exemplary embodiment of the present invention may include

[A] an alkali-soluble resin of 5 to 50 wt%,

[B] a unsaturated ethylene-based monomer of 5 to 60 wt%,

[C] a silsesquioxane-based compound of the following Chemical Formula 1 of 5 to 60 wt%,

[D] a photopolymerizable initiator of 0.5 to 20 wt%,

[E] a solvent of 20 to 80 wt%, and other additives.

The photosensitive resin composition according to the exemplary embodiment of the present invention may have dielectric constant of 3.3 or less after forming a thin film so as to provide low permittivity suitable for a display process.

Further, the photosensitive resin composition for the organic insulator according to the exemplary embodiment of the present invention may have viscosity of 3 to 30cps in order to form a uniform film in coating.

Each constituent element of the photosensitive resin composition according to the exemplary embodiment of the present invention will be described in detail.

[A] Alkali-soluble resin

The [A] alkali-soluble resin used in the exemplary embodiment may be a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride and [a2] an unsaturated compound containing an epoxy group; a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2]; a copolymer of one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3]; or a copolymer acquired by radical-polymerizing one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2], and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3].

First, unsaturated carboxylic acid and/or unsaturated carboxylic anhydride of [a1] form may use acrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, and a single or a combination of anhydrides of the dicarboxylic acids. Among them, acrylic acid, methacrylic acid, maleic anhydride, and the like are preferably used in view of copolymerization reactivity, heat resistance, and easy obtainment.

The [a2] unsaturated compound containing an epoxy group may be acrylic glycidyl ester, methacrylic glycidyl ester, α-ethyl acrylic glycidyl ester, α-n-propyl acrylic glycidyl ester, α-n-butyl acrylic glycidyl ester, acrylic-3,4-epoxy butyl ester, methacrylic-3,4-epoxy butyl ester, acrylic-6,7-epoxy heptyl ester, methacrylic-6,7-epoxy heptyl ester, α-ethyl-acrylic-6,7-epoxy heptyl ester, o-vinyl benzyl grycidyl ether, m-vinyl benzyl grycidyl ether, p-vinyl benzyl grycidyl ether, and the like, but they are preferably used in view of increasing copolymerization reactivity and heat resistance and hardness of the acquired thin film. The compounds [a2] are used alone or in combination.

As the compound [a3], for example, methacrylic acid alkyl esters such as methyl acrylate, isopropyl acrylate, and acrylic acid alkyl ester methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, sec-butyl methacrylate, t-butyl methacrylate, and the like; acrylic acid alkyl esters such as methyl acrylate, isopropyl acrylate, and the like; methacrylic cycloalkyl esters such as cyclohexyl methacrylate, 2-methyl-cyclohexyl methacrylate, dicyclopantenyl methacrylate, dicyclopantenyloxyethyl methacrylate, isobonyl methacrylate, and the like; acrylic cycloalkyl esters such as cyclohexyl acrylate, 2-methyl-cyclohexyl acrylate, dicyclopantenyl acrylate, dicyclopantenyloxyethyl acrylate, isobonyl acrylate, and the like; methacylic aryl esters such as pentyl methacrylate, benzyl methacrylate, and the like, acrylic aryl esters such as pentyl acrylate, benzyl acrylate, and the like; dicarboxylic acid diesters such as diethyl maleic acid, diethyl fumaric acid, diethyl itaconic acid, and the like; hydroxylalkyl esters such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and the like may be used.

The compound [a4] may be, for example, styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, vinyl toluene, p-methoxy styrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinyliden chroirde, acrylamide, methacrylamide, vinyl acetic acid, 1,3-butadiene, isoprene, 2,3-dimethyl-1 ,3-butadiene, and the like.

The copolymer [A] used in the exemplary embodiment of the present invention may be 5 to 50 wt% with respect to the entire content of the composition and herein, a [a1]:[a2] component is included by a weight ratio of 1:1.3 to 3.5 and when a component selected from the [a3] and [a4] is included, the component selected from the [a3] and [a4] may be included by 35 to 65 wt% with respect to the entire content of the [A] alkali-soluble resin.

The [A] alkali-soluble resin may have the solid content of 10 to 70 wt% with respect to the [A] component and more preferably, 20 to 50 wt%. When the solid content is less than 10 wt%, storage stability of the copolymer [A] and polymerization control at the time of manufacturing a polymer including all of the constituent element of the [a1] to [a4] are not performed well such that the resin tends to be solidified, and when the solid content is more than 10 wt%, a developing property, heat resistance, surface hardness, and the like tend to be deteriorated.

The solvent used for the synthesis of the copolymer [A] is preferably alcohols such as methanol, ethanol, and the like; ethers such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol ether, and the like; propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, and the like.

The polymerizable initiator used for the synthesis of the copolymer [A] may use a generally known radical polymerizable initiator. For example, azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobis-(4-methoxy-2,4-dimethylvaleronitrile), and the like; organic peroxides such as benzoyl peroxide, t-butylperoxypivalate, 1,1'-bis-(t-butylperoxy)cyclohexane, and the like; and hydrogen peroxide may be used as the polymerizable initiator. In the case where hydrogen peroxide is used as the radical polymerizable initiator, the polymerizable initiator may be used as a redox initiator by using peroxide together with a reducing agent.

[B] Unsaturated ethylene-based monomer

The unsaturated ethylene-based monomer used in the exemplary embodiment is a monofunctional or multifunctional acryl monomer having one or more unsaturated ethylene bond and monofunctional, bifunctional, or trifunctional or more (meth)acrylate is preferable in that polymerization is good and heat resistance and surface hardness of an acquired protective film are improved.

The monofunctional (meth)acrylate may be, for example, 2-hydroxyethyl (meth)acrylate, kabitol (meth)acrylate, isobonyl (meth)acrylate, 3-methoxy butyl (meth)acrylate, 2-(meth)acryloyl oxy ethyl 2-hydroxy propyl phthalate, and the like.

The difunctional (meth)acrylate may be, for example, ethyleneglycol (meth)acrylate, 1,6-hexanediol (meth)acrylate, 1,9-nonandiol (meth)acrylate, propyleneglycol (meth)acrylate, tetraethyleneglycol (meth)acrylate, bisphenoxy ethylalcohol fluorene diacrylate, and the like.

The trifunctional (meth)acrylate may be, for example, trishydroxyethyl isocyanurate tri(meth)acrylate, trimethyl propane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like.

The monofunctional, bifunctional, or trifunctional or more (meth)acrylate is used alone or in combination.

[C] Silsesquioxane-based compound

Since the silsesquioxane-based compound having an epoxy group used in the related art is not related to curing during an exposing process, a pattern is lost or a lot of loss occur in a subsequent developing process. The silsesquioxane-based compound used in the exemplary embodiment has an acryl group or an oxetal group, in which curing density during the exposing process increases to minimize a pattern loss and a film loss during a developing process, heat resistance of the protective film is excellent, and it is preferable in view of transparency, hardness, and permittivity.

Further, the content of the used silsesquioxane may be 5 to 60 w% with respect to the entire content of the composition. When the content thereof is less than 5 wt%, heat resistance, transparency, hardness, and permittivity are deteriorated and when the content thereof is more than 60 wt%, the development in the developing process tends not to be progressed.

An detailed example of the silsesquioxane-based compound may be represented by the following Chemical Formula 1.

[D] Photopolymerizable initiator

The photopolymerizable initiator in the exemplary embodiment means a compound which is decomposed or bonded by the exposure and generates active species such as a radical, an anion, a cation, and the like capable of initiating the polymerization of the [B] unsaturated ethylene-based monomer.

The photocurable resin composition includes the photopolymerizable initiator so as to have the content of 0.5 to 20 wt% of the entire composition. If the content thereof is less than 0.5 wt%, sensitivity of the protective film is insufficient, such that the protective film is easily lost in the developing process and although the protective film is maintained in the developing process, it is difficult to acquire the protective film having much high crosslink density. When the content of the photopolymerizable initiator is more than 20 wt%, heat resistance, flatness, and the like of the protective film are easily deteriorated.

An example of the photopolymerizable initiator may be ketones such as thioxanetone, 2,4-diethyl thioxanetone, thioxaneton-4-sulfonic acid, benzophenone, 4,4'-bis(diethyl amino)benzophenone, acetophenone, p-dimethylaminoacetophenone, α,α'-dimethoxyacethoxy benzophenone, 2,2'-dimethoxy-2-phethylacetophenone, p-methoxyacetophenone, 2-methyl[4-(methylthio)phenyl]-2-morpholino-1-prophanone, 2-benzil-2-diethylamino-1-(4-morpholinophenyl)-butane-1-on, 2-hydroxy-2-methyl-1-phenylpropane-1-on, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenylketone, and the like, quinones such as anthraquinone, 1,4-naphthoquinone, and the like; halogen compounds such as 1,3,5-tris(trichrloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2-chlorophenyl)-s-triazine, 1,3-bis(trichlorophenyl)-s-triazine, phenacylchloride, tribromomethyl phenylsulfone, tris(trichloromethyl)-s-triazine, and the like, peroxides such as di-t-butyl peroxide and the like, and acyl phosphine oxides such as 2,4,6-trimethyl benzoyl diphenyl phosphine oxide and the like.

The photopolymerizable initiator may be used alone or in combination.

[D] Solvent

The solvent used in the exemplary embodiment of the present invention is a solvent maintaining solid and viscosity of the composition in the manufacturing of the copolymer [A] and materials as follows are available. In detail, the solvent may be alcohols such as methanol, ethanol, and the like; ethers such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and the like; propylene glycol alkyl ether acetates such as propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, and the like; and the like. Among the solvents, in view of solubility, reactivity with each component, and convenience of the film formation, the solvent may be ethers such as diethylene glycol dimethyl ether, diethylene glycol di-ethyl ether, propylene grycol methyl ether, kentones such as methylethylketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanan, esters such as methyl ester, ethyl ester, propyl ester, and butyl ester of acetic acid; ethyl ester and methyl ester of 2-hydroxy-propionic acid; ethyl ester of 2-hydroxy-2-methyl-propionic acid; methyl ester, ethyl ester, and butyl ester of hydroxy-acetic acid; ethyl lactate, propyl lactate, and butyl lactate; methyl ester, ethyl ester, propyl ester, and butyl ester of methoxyacetate; methyl ester, ethyl ester, propyl ester, and butyl ester of propoxyacetate; methyl ester, ethyl ester, propyl ester, and butyl ester of butoxyacetate; methyl ester, ethyl ester, propyl ester, and butyl ester of 2-methoxypropionic acid; methyl ester, ethyl ester, propyl ester, and butyl ester of 2-ethoxypropionic acid; methyl ester, ethyl ester, propyl ester, and butyl ester of 2-butoxypropionic acid; methyl ester, ethyl ester, propyl ester, and butyl ester of 3-methoxypropane; methyl ester, ethyl ester, propyl ester, and butyl ester of 3-ethoxypropionic acid; methyl ester, ethyl ester, propyl ester, butyl ester of 3-butoxypropionic acid, and the like.

Further, a solvent having a high melting point may be used in combination with the solvent. The combined high-melting point solvent may be, for example, N-methyl formamide, N, N-dimethylformamide, N-methyl acetamide, N, N-dimethylacetamide, N-methyl pyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, and the like.

In addition, other additives which can be added may be a surfactant in order to improve a coating property. The surfactant may be fluorine and silicon-based surfactants and for example, may be FC-129, FC-170C, and FC-430 of 3M Co., Ltd., F-172, F-173, F-183, F-470, and F-475 of DIC Co., Ltd., KP322, KP323, KP340, and KP341 of Shin-Etsu Silicon Co., Ltd., and the like. The content of the surfactant is preferably 5 parts by weight or less with respect to 100 parts by weight of the copolymer [A] and more preferably 2 parts by weight or less. When the content of the surfactant is more than 5 parts by weight, a bubble is easy to occur in coating.

Further, an adhesive additive may also be used in order to improve adhesion with gas. A functional silane coupling agent is preferably used as the adhesive additive and for example, trimethoxysilyl benzoate, ν-methacryloxypropyltrimethoxy silane, vinyltriacetoxy silane, vinyltrimethoxy silane, ν-isocyanate propyltrimethoxy silane, ν-glycidoxypropyltrimethoxy silane, and the like. The content of the adhesive additive is preferably 20 parts by weight or less with respect to 100 parts by weight of the copolymer [A] and more preferably 10 parts by weight or less. When the content of the adhesive additive is more than 20 parts by weight, the heat resistance is easily deteriorated.

Hereinafter, examples and comparative examples of the present invention will be described. However, the examples described below are only an exemplary embodiment of the present invention and the present invention is not limited to the examples described below.

<Preparation Example 1> Preparation of alkali-soluble resin A

2,2'-azobis iso-butylonitrile of 10 parts by weight as the polymerizable initiator was dissolved in propyleneglycol monomethylether acetate of 200 parts by weight in a reactor provided with a cooling pipe and an agitator. Subsequently, styrene of 65 parts by weight, methacrylate of 15 parts by weight, and glycidyl methacrylate of 20 parts by weight were added therein and started to be softly mixed after the nitrogen substitution. A temperature of the solution increased by 70℃ and the temperature was maintained for 4 hours, thereby acquiring the polymer solution including the copolymer. The solid concentration of the acquired polymer solution was 35%. This was referred to as the alkali-soluble resin A.

<Preparation Example 2> Preparation of alkali-soluble resin B

The polymer solution was prepared in the same method as Preparation Example 1, but styrene of 45 parts by weight instead of styrene of 65 parts by weight and dicyclopentyl acrylate of 20 parts by weight were used. The solid concentration of the acquired polymer solution was 33%. This was referred to as the alkali-soluble resin B.

The alkali-soluble resins A and B as a photosensitive material, propyleneglycol monomethylether acetate as a solvent, the monomer having a unsaturated ethylene bond (dipentaerytritol hexa(meth)acrylate) were combined and the silsesquioxane-based compound was combined therein by changing the content thereof as shown the following Table 1, thereby preparing the photosensitive resin.

Table 1

Classification	[A] alkali-soluble resin-A	[A] alkali-soluble resin-B	[B] hexafunctional ethylene	[C] silsesquioxane-based compound	[D] oxime-based photopolymerizable initiator	[E] solvent	[F] silsesquioxane-based compound having epoxy group
Example 1	9	-	15	5	1	70	-
Example 2	9	-	10	10	1	70	-
Example 3	9	-	5	15	1	70	-
Example 4	-	9	10	10	1	70	-
Example 5	-	9	5	15	1	70	-
Comparative Example 1	9	-	10	-	1	70	10
Comparative Example 2	-	9	10	-	1	70	10
Comparative Example 3	9	-	20	-	1	70	-

(Note)

1) A content unit is wt%.

2) The [C] silsesquioxane-based compound is a compound represented by Chemical Formula 1 according to the present invention and R is an acryl group, R₁ and R₂ are a methoxy group respectively, m is 3, and n is 5.

3) The [F] silsesquioxane-based compound having an epoxy group generally uses HQ504.

The composition prepared in Examples and Comparative Examples was evaluated with respect to mechanical properties as follows and the result was shown in the following Table 2.

(1) Viscosity

The viscosity was measured by a Brookfield viscometer at 25℃.

(2) Residual film ratio

The prepared photo sensitive composition was spin-coated on glass and pre-dried at a hotplate at 100℃ for 120 seconds, thereby forming the photoresist film having a film thickness of 3㎛. The glass formed with the film was exposed and then, developed in a 2.38%TMAH aqueous solution and highly heated at 220℃ for 1 hour again. The film thickness in the pre-drying and the thickness of the film formed after removing the solvent through a post-curing were measured, thereby measuring the residual film ratio through a ratio measurement.

(3) Flatness

The photo sensitive composition with the patterned colorresist prepared on the glass was spin-coated on glass and pre-dried at a hotplate at 100℃ for 120 seconds, thereby forming the photoresist film having a film thickness of 3㎛. The glass formed with the film was exposed and then, developed in a 2.38%TMAH aqueous solution for 60 seconds and highly heated at 220℃ for 1 hour again. A thickness of 5 points of the acquired dried film was measured, thereby measuring the flatness.

By measuring the flatness, the case where the thickness deviation is less than 0.025㎛ was represented by ◎, 0.026㎛ to 0.05㎛ represented by ○, 0.06㎛ to 0.1㎛ represented by △, and more than 0.1㎛ represented by X.

(4) Sensitivity

The photo sensitive composition prepared on the glass was spin-coated by 800 rpm, pre-dried at a hotplate at 100℃ for 120 seconds, exposed by the exposing amount of 60, 70, 80, 90, 100, 150, and 200mJ/㎠, developed in a 2.38%TMAH aqueous solution for 60 seconds, and highly heated at 220℃ for 1 hour again. The thickness of the acquired film was measured.

By measuring the thickness, when the thickness contrast of the acquired film in 200mJ/㎠ was 90% or more, the thickness was selected as the sensitivity in each composition.

(5) Heat resistance

Upper, lower, left, and right widths of the pattern film formed in the sensitivity measurement were measured. In this case, on the basis before a mid-bake (100℃ for 2 minutes), the case where the change rate of angle is 0 to 10% was represented by ◎, 11 to 20% represented by ○, 21 to 40% represented by △, and more than 40% represented by X.

(6) Adhesion

The photo sensitive composition prepared on the glass was spin-coated, pre-dried at a hotplate at 100℃ for 120 seconds, exposed by the exposing amount of 60, 70, 80, 90, 100, 150, and 200mJ/㎠, developed in a 2.38%TMAH aqueous solution for 60 seconds, and highly heated at 220℃ for 1 hour again. After cutting the acquired film into 100 equal parts, the cut film was attached and then, detached by using a 3M scotch magic tape. In this case, the number of the remaining film was counted.

The case where the remaining film in the measurement is 100% was represented by ◎, 90 to 99% represented by ○, 80 to 89% represented by △, and less than 80% represented by X.

(7) Permittivity

The permittivity was calculated through the following Equation by measuring capacitance of a capacitor. The capacitance was measured through an impedance analyzer after coating a dielectric thin film with a predetermined thickness and each dielectric constant was calculated through the following Equation 1.

[Equation 1]

C (capacitance) =ε0(vacuum permittivity)*εr(specific inductive capacity of dielectric thin film)*A (effective area) / d (thickness of dielectric thin film)

By measuring the dielectric constant, the case where the dielectric constant was 2.8 to 3.0 was represented by ◎, 3.1 to 3.3 represented by ○, 3.4 to 3.6 represented by △, and 3.7 or more represented by X.

(8) Transmittance

Transmittance in 400nm was measured by using a spectrophotometer.

(9) Resolution

The photo sensitive composition prepared on the glass was spin-coated by 800 rpm, pre-dried at a hotplate at 100℃ for 120 seconds, exposed by the exposing amount of 100mJ/㎠ by using a mask for each size (4㎛ to 100㎛), developed in a 2.38%TMAH aqueous solution for 60 seconds, and highly heated at 220℃ for 1 hour again. In this case, the pattern size of the acquired film was measured.

Table 2

Classification	Composition viscosity(cps)	Flatness	Sensitivity (mJ/㎠)	Heat resistance	Adhesion	Permittivity	Residual film ratio(%)	Transmittance(%)	Resolution(㎛)
Example 1	5	○	70	◎	◎	◎	90	93	8
Example 2	5	○	70	○	◎	◎	92.5	95	6
Example 3	5	○	70	○	◎	◎	93	95.5	5
Example 4	5	○	70	◎	◎	◎	95.4	97	5
Example 5	5	○	70	◎	◎	◎	97	98	4
Comparative Example 1	5	○	150	○	◎	◎	93	93	20
Comparative Example 2	5	○	150	○	○	◎	94.5	95	14
Comparative Example 3	5	○	70	△	△	△	89	89.5	16

In Table 2, the photosensitive resin compositions manufactured in Examples 1 to 5 according to the present invention had excellent heat resistance, adhesion, residual film ratio, and transmittance and since the permittivity was low, the consumption power may be reduced and since the fine pattern can be implemented without loss of the pattern, the photosensitive resin compositions may be effectively applied to the organic insulator in various display processes.

Simple modifications and changes and modifications of the present invention can be easily made by those skilled in the art and it can be understood that these modifications and changes are included in the scope of the present invention.

Claims

A photosensitive resin composition for an organic insulator, comprising: [A] an alkali-soluble resin, [B] a unsaturated ethylene-based monomer, [C] a silsesquioxane-based compound of the following Chemical Formula 1, [D] a photopolymerizable initiator, and [E] a solvent.

<Chemical Formula 1>

(Herein, R is an acryl group or an oxetal group, R1 is a C1-C5 alkyl group or a hydrogen atom, R2 is a C1-C5 alkoxy group, a C1-C5 alkyl group, or a hydrogen atom, and m and n are 1 to 10 respectively.)
The photosensitive resin composition for an organic insulator of claim 1, wherein a molecular weight of the [C] silsesquioxane-based compound is 1000 to 4000.
The photosensitive resin composition for an organic insulator of claim 1, wherein the [C] silsesquioxane-based compound is bifunctional to trifunctional.
The photosensitive resin composition for an organic insulator of claim 1, wherein the content of the [C] silsesquioxane-based compound is 5 wt% to 60 wt% with respect to the entire content of the composition.
The photosensitive resin composition for an organic insulator of claim 1, wherein the [A] alkali-soluble resin is a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic acid anhydride; and [a2] an unsaturated compound containing an epoxy group.
The photosensitive resin composition for an organic insulator of claim 5, wherein the [A] alkali-soluble resin is a copolymer of [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2]; a copolymer of one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3]; or a copolymer acquired by radical-polymerizing one or more compound selected from [a1] a single or a mixture of two or more selected from unsaturated carboxylic acid and unsaturated carboxylic anhydride, [a2] an unsaturated compound containing an epoxy group, and [a3] an olefin-based unsaturated carboxylic acid ester compound in addition to the [a1] and [a2], and [a4] an olefin-based unsaturated compound in addition the [a1], [a2] and [a3].
The photosensitive resin composition for an organic insulator of claim 5, wherein the [a1]:[a2] component is included by a weight ratio of 1:1.3 to 2.5.
The photosensitive resin composition for an organic insulator of claim 6, wherein the [a1]:[a2] component is included by a weight ratio of 1:1.3 to 2.5 and the content of one or more compound selected from the [a3] and [a4] components is 35 to 65 wt% with respect to the entire content of the [A] alkali-soluble resin.
The photosensitive resin composition for an organic insulator of claim 1, wherein the content of the [A] alkali-soluble resin is 5 to 50 wt% with respect to the entire content of the composition.
The photosensitive resin composition for an organic insulator of claim 1, wherein the [A] alkali-soluble resin has the solid content of 10 to 70 wt%.
The photosensitive resin composition for an organic insulator of claim 1, wherein the [B] unsaturated ethylene-based monomer is an acryl monomer having two or more unsaturated ethylene bonds and the content thereof is 5 to 60 wt% with respect to the entire content of the composition.
The photosensitive resin composition for an organic insulator of claim 1, wherein a dielectric constant after forming the thin film is 3.3 or less.
The photosensitive resin composition for an organic insulator of claim 1, wherein viscosity is 3 to 30 cps.
An organic insulator fabricated by using the composition according to any one of claims 1 to 13.
A display device including the organic insulator according to claim 14.