TW201610568A - Photocrosslinkable resin composition, insulation film formed therefrom, and OLED using the film - Google Patents

Abstract

Disclosed herein are a photocrosslinkable resin composition comprising an alkali-soluble resin (A), an ethylenically unsaturated monomer (B), a photoinitiator (C), and a liquid repellent polymer (D), an insulation film formed therefrom, and an organic light-emitting diode comprising the insulation film.

Description

Photocrosslinking resin composition, insulating film formed from the composition, and organic light emitting diode using the same

The present invention relates to a photocrosslinked resin composition, and more particularly to a liquid repellent polymer comprising polylysine as an alkali-soluble resin, an ethylenically unsaturated monomer, a photoinitiator, and a fluorine-containing alkyl acrylate. Photocrosslinking resin composition. Furthermore, the present invention relates to an insulating film formed of the photocrosslinked resin composition, and an organic light emitting diode using the same.

The photocrosslinking resin composition has a wide range of applications, and can be used as a photoresist material for ITO electrodes of liquid crystal displays (LCDs), organic EL displays (OLEDs), etc., as a dielectric insulating film, and a circuit protection film. The color filter of the color filters of LCDs, etc., disperses the photoresist material, as a permanent film of OLEDs, such as a septa. In recent years, the demand for LCDs and OLEDs for television displays, screens, and the like has increased dramatically, and thus the demand for photocrosslinking resin compositions used in the manufacture of LCDs and OLEDs has increased. The increased demand for color filters is subject to cost reduction requirements. In this regard, an inkjet printing method with low production cost has been proposed.

Fabrication of color filters by inkjet printing is substantially accomplished by forming spacers by photolithography to define pixels and applying red, green, and blue inks to the pixels via inkjet printing. This method is simpler than the conventional method and has an economic advantage over the conventional method of using pigment dispersion photoresist in terms of ink consumption. However, in the case of an inkjet printing method, when an ink droplet is applied to a pixel, it is necessary that the substrate and the side of the spacer are sufficiently hydrophilic to be closely bonded to the ink while the spacer has a liquid repellent surface to Prevents ink from dripping through the spacers into adjacent pixels or in combination with ink drops in adjacent pixels.

Accordingly, the present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide light-induced light-precision circuits which are capable of forming highly fine circuits without generating residues and ensuring high light transmittance and low dielectric constant. Crosslinked resin composition.

Another object of the present invention is to provide an insulating film formed of the photocrosslinked resin composition having a contact angle of 40 or more with respect to propylene glycol monomethyl ether acetate (PGMEA) and preventing water solubility The luminescent material causes blurring between pixels.

Still another object of the present invention is to provide an OLED using the photocrosslinked resin composition which exhibits high contrast, thereby realizing a high definition pattern.

In order to achieve the above object, the present invention provides a photocrosslinking resin composition comprising an alkali-soluble resin (A), an ethylenically unsaturated monomer (B), a photoinitiator (C), and a liquid-repellent polymer ( D), the alkali-soluble resin (A) is a polyamic acid containing a repeating unit represented by the following Chemical Formula 2, and the liquid-repellent polymer (D) contains a fluoroalkyl acrylic acid represented by the following Chemical Formula 1. ester:

Wherein A is a C1 to C10 fluoroalkyl group (Rf) or perfluoropolyether (PFPE) group, and B is H, CH ₃ or a halogen atom;

Wherein R ₁ and R ₂ may be the same or different, each independently being a di- to octavalent organic group containing two or more carbon atoms, and R ₃ and R ₄ may be the same or different, individually independent The ground is an organic group having a hydroxyl group and having 1 to 12 carbon atoms, a hydrogen atom or a halogen atom, x is an integer of 0 to 2, and y is an integer of 0 to 4, provided that x+y>0 , z is an integer from 0 to 2, and n is an integer from 10 to 200.

Furthermore, the present invention provides an insulating film formed by crosslinking the photocrosslinked resin composition.

Further, the present invention provides an organic light emitting diode comprising the insulating film.

The above and other objects, features and advantages of the present invention will become more apparent from the description of the accompanying claims claims

Unless otherwise defined, all technical and scientific terms used in the specification are intended to have the same meaning In general, the nomenclature used in this specification is well known in the art and found in general practice.

Throughout the specification and the scope of subsequent patent applications, the terms "comprise" and variations, such as "comprises" and "comprising", are to be understood to mean, unless the context requires otherwise. Including the integers, compositions, or steps, or integers or groups of steps, and optionally any additional integers, compositions, or steps, or integers, compositions, or groups of steps, including the absence of additional integers, The composition or step is a specific example of an integer, a composition, or a group of steps. In the latter specific example, the term "comprising" is equivalent in scope to "consisting of".

Hereinafter, a detailed description of the present invention will be provided.

According to an aspect of the invention, there is provided a photocrosslinking resin composition comprising: an alkali-soluble resin (A), an ethylenically unsaturated monomer (B), a photoinitiator (C), and a liquid repellency The polymer (D) is a polylysine having a repeating unit represented by the following Chemical Formula 2, and the liquid repellency polymer (D) contains a fluoroalkyl acrylic acid represented by the following Chemical Formula 1. ester:

Wherein A is a C1 to C10 fluoroalkyl group (Rf) or a perfluoropolyether (PFPE) group, and B is H, CH ₃ or a halogen atom;

Wherein R ₁ and R ₂ may be the same or different, each independently being a di- to octavalent organic group containing two or more carbon atoms, and R ₃ and R ₄ may be the same or different, individually independent The ground is an organic group having a hydroxyl group and having 1 to 12 carbon atoms, a hydrogen atom or a halogen atom, x is an integer of 0 to 2, and y is an integer of 0 to 4, provided that x+y>0 , z is an integer from 0 to 2, and n is an integer from 10 to 200.

In a preferred embodiment of the present invention, the photocrosslinkable resin composition contains 5 to 80 parts by weight of the ethylenically unsaturated monomer (B), 0.5 to 100 parts by weight based on the alkali-soluble resin (A). 10 parts by weight of the photoinitiator (C), and 0.5 to 10 parts by weight of the fluoroalkyl acrylate-containing liquid repellent polymer (D).

Hereinafter, the components of the photocrosslinkable resin composition according to the present invention will be described in detail.

Alkali-soluble resin (A)

Alkali-soluble resin - a binder used as the photocrosslinking resin composition of the present invention - is a poly-proline which has a repeating unit represented by the following Chemical Formula 2: [Chemical Formula 2]

Wherein R ₁ and R ₂ may be the same or different, each independently being a di- to octavalent organic group containing two or more carbon atoms, and R ₃ and R ₄ may be the same or different, individually independent The ground is an organic group having 1 to 12 carbon atoms, a hydrogen atom or a halogen atom having a hydroxyl group, x is an integer of 0 to 2, and y is an integer of 0 to 4, provided that x+y>0, z is an integer from 0 to 2, and n is an integer from 10 to 200.

In Chemical Formula 2, it is preferred that they may be the same or different, and each independently is an organic group containing at least one phenyl group or containing at least one phenyl group and a C1 to C10 hydrocarbon moiety, which may have a fluorine. An atom is a substituent, and any one of the carbon atoms may be substituted with an ether group (-O-) or a fluorenyl group (--SO ₂ -), and x and y are independently an integer of 0 to 2, provided that x +y>0, and Z is an integer of 1 or 2.

In Chemical Formula 2, R ₁ and R ₂ are the same or different from the viewpoint of polymerization and imidization, and are preferably independently a biphenyl group containing a C 2 to C 8 fluoroalkyl group. For example, R ₁ and R ₂ may each be —[(C ₆ H ₃ ) ₂ C(CF ₃ ) ₂ ]-. Further, from the viewpoint of developing properties, R ₃ and R ₄ may be the same or different, and each of them is independently an organic group having 1 to 4 carbon atoms having a hydroxyl group, or preferably a hydrogen atom. More preferably, R ₃ and R _{4 are each} independently an organic group having 1 to 4 carbon atoms having a hydroxyl group.

In Chemical Formula 2, n is preferably an integer of from 10 to 200, more preferably an integer of from 20 to 50, from the viewpoint of solubility.

For example, in order to be used as the alkali-soluble resin of the present invention, the polyamic acid resin can be prepared by polymerizing an aromatic diamine and an aromatic dianhydride in a first solvent. The resulting reaction mixture contains the polyamic acid resin, which is a quinone imine precursor, which can be added together with the additive and subsequently used without imidization. Alternatively, the polyamic acid resin is precipitated, filtered and dried in a second solvent.

There are no particular restrictions on the aromatic diamine. It may be selected from the group consisting of 2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (bis-AP-AF), 2,2-bis[4- (4-amino-phenoxy) - phenyl] propane (6HMDA), 2,2 '- bis (trifluoromethyl) -4,4' - diamino biphenyl (2,2 '-TFDB) , 3,3 ' -bis(trifluoromethyl)-4,4 ' -diaminobiphenyl (3,3 ' -TFDB), 4,4 ' -bis(3-aminophenoxy) Benzoquinone (DBSDA), bis(3-aminophenyl)anthracene (3DDS), bis(4-aminophenyl)anthracene (4DDS), 1,3-bis(3-aminophenoxy)benzene ( APB-133), 1,4- bis (4-aminophenoxy) benzene (APB-134), 2,2 ' - bis [3 (3-aminophenoxy) phenyl] hexafluoropropane ( 3-BDAF), 2,2 '- bis [4 (4-aminophenoxy) phenyl] hexafluoropropane (4-BDAF), oxygen dianiline (ODA), and of their combinations. In particular, 2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (bis-AP-AF) is preferred from the viewpoint of light transmittance and heat resistance.

Examples of aromatic dianhydrides useful in the present invention include, but are not limited to, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA), 4-(2,5-dionetetrahydrofuran -3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dianhydride (TDA), 4,4 ' -(4,4 ' -isopropylidenediphenoxy) bis ( phthalic anhydride) (HBDA), 3,3 '- (4,4' - oxy phthalic anhydride) (ODPA), 3,4,3 ', 4' - biphenyl tetracarboxylic acid The anhydride (BPDA), and combinations thereof, are preferably 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) from the viewpoint of light transmittance and heat resistance.

The aromatic diamine and the aromatic dianhydride are dissolved in the first solvent in a molar ratio of 1:0.8 to 1:1, and polymerized into a polyamic acid resin. When the aromatic dianhydride is used in an amount of less than 0.80 mole per mole of aromatic diamine, the polylysine obtained after polymerization of the aromatic diamine and the aromatic dianhydride has a small molecular weight, resulting in a significantly poor yield. And pattern processing. On the other hand, when the amount of the aromatic dianhydride is more than 1 mol, the molecular weight of the polyproline is difficult to be constant because it is unstable.

The polyamine obtained thus obtained has a weight average molecular weight of 10,000 to 40,000 g/mol at a viscosity of 50 to 200 cps, which can realize a highly fine pattern. By convention, the viscosity system increases or decreases in proportion to the final weight average molecular weight. Therefore, when the viscosity of the poly-proline exceeds the range, the weight average molecular weight excessively increases or decreases, resulting in deterioration of pattern development.

The conditions for the polymerization are not particularly limited. The polymerization is preferably carried out at a temperature of 15 to 25 ° C for 20 minutes to 5 hours in consideration of the polymerization rate. Since oxygen is likely to act as an inhibitor, the polymerization is preferably carried out in an inert atmosphere such as argon or nitrogen.

After the aromatic diamine and the aromatic dianhydride are polymerized into polyphthalic acid in the first solvent, the photoinitiator and the ethylenically unsaturated monomer can be added to the first solvent without further purification. It is better in terms of efficiency. Alternatively, the polyamic acid can be precipitated and dried to obtain a powder. In this case, a photoinitiator may be added to the solvent (E) together with the ethylenically unsaturated monomer and the powder.

Any solvent can be used as the first solvent for the polymerization of the monomer as long as it can dissolve the polyamic acid. The first solvent may be at least one polar solvent selected from the group consisting of: m-cresol, propylene glycol monomethyl ether acetate (PGMEA), N-methyl-2-pyrrolidone (NMP), two Methylformamide (DMF), dimethylacetamide (DMAc), dimethyl hydrazine (DMSO), acetone and diacetic acid. Alternatively, examples of the first solvent may include, but are not limited to, tetrahydrofuran (THF), chloroform, and γ-butyrolactone.

The amount of the first solvent is not particularly limited. However, in order to impart a suitable viscosity to the polyaminic acid solution, the first solvent is preferably used in an amount of 50 to 95% by weight, more preferably 70 to 90% by weight, based on the total amount of the polyaminic acid solution. The weight is the benchmark.

In another embodiment of the present invention, the polyamic acid resin thus obtained may be precipitated and dried to obtain a powder. The powdered polyglycine is recovered and dissolved in the solvent (E) before being prepared as a photocrosslinked resin composition.

The principle of precipitating polyamic acid resins is based on the difference in solubility between the two different solvents using polyglycine. That is, a second solvent which cannot dissolve the polyamic acid can be used. The second solvent may be lower in polarity than the first solvent. In particular, the second solvent may be selected from the group consisting of water, alcohols, non-polar solvents such as hexanes, ethers, ketones, and combinations thereof.

There is no particular limitation on the amount of the second solvent. Preferably, the amount of the second solvent is between 200 and 1,000 parts by weight based on 100 parts by weight of the alkali-soluble resin. When the amount of the second solvent is less than 200 parts by weight, the polyamic acid resin may be difficult to precipitate and purify. On the other hand, the amount of the second solvent portion exceeding 1,000 parts by weight deteriorates workability.

As described above, the polyamic acid resin in the second solvent can be isolated by filtration and drying. The drying may be carried out at 50 to 100 ° C for 12 to 24 hours in consideration of the boiling point of the second solvent which may remain in the polyamic acid and the first solvent.

It is preferred that the polyamic acid resin thus obtained has a weight average molecular weight (measured by GPC) of between 10,000 and 40,000 g/mol. Providing this average molecular weight range allows the polyphthalic acid resin to achieve high resolution in the patterning process.

As used herein, the term "weight average molecular weight" is defined as the value converted to polystyrene equivalent as measured by gel permeation chromatography (GPC).

Ethylenically unsaturated monomer (B)

For the purposes of this disclosure, the term "ethylenically unsaturated monomer" refers to a mono- or poly-functional acrylic monomer bearing one or more ethylenically unsaturated bonds, once the photocrosslinked resin composition Initiating photopolymerization, the monomer acts as a cross-linking backbone. More preferably, the ethylenically unsaturated monomer is a mono-, di-, or tri- or higher functional (meth) acrylate because of its high polymerization ability and imparts improved heat resistance and surface hardness to the resulting protective film. .

Examples of monofunctional (meth) acrylates include 2-hydroxyethyl (meth) acrylate, carbitol (meth) acrylate, isobornyl (meth) acrylate, 3-methoxy butyl Base (meth) acrylate and 2-(methyl) propylene decyl ethyl 2-hydroxy phthalate, but not limited to them.

As the bifunctional (meth) acrylate, examples thereof include, but are not limited to, ethylene glycol (meth) acrylate, 1,6-hexane diol (meth) acrylate, 1,9-nonanediol (Meth) acrylate, propylene glycol (meth) acrylate, tetraethylene glycol (meth) acrylate, and bis-phenoxyethanol hydrazine diacrylate.

Illustrative but non-limiting examples of tri- or higher functional (meth) acrylates include trishydroxyethyl isocyanurate, tri(meth) acrylate, trimethylpropane tri(meth) acrylate Pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

Such mono-, di-, and tri- or higher-functional (meth) acrylates may be used singly or in combination.

In the photocrosslinkable resin composition of the present invention, the ethylenically unsaturated single system is used in an amount of 5 to 80 parts by weight based on 100 parts by weight of the alkali-soluble resin. When the ethylenically unsaturated monomer content falls within the range, the photocrosslinkable resin composition has an advantage in patterning, adhesive strength and hardness, making it easy to carry out a developing process.

Photoinitiator (C)

The photocrosslinkable resin composition of the present invention comprises a photoinitiator. As used herein, the term "photoinitiator" refers to a compound that degrades or associates light energy to form an active species capable of initiating a polymerization reaction, such as a free radical, an anion or a cation. The photoinitiator acts to cause a chemical crosslinking reaction of the ethylenically unsaturated monomer (B).

Any photoinitiator (C) conventionally used in the art can be used. Examples of photoinitiators include: ketones such as thioxanthone, 2,4-diethylthioxanthone, thioxanthone-4-sulfonic acid, benzophenone, 4,4 '-Bis(diethylamino)benzophenone, acetophenone, p-dimethylaminoacetophenone, a, a'-dimethoxyacetoxybenzophenone, 2, 2'-dimethoxy-2-phenylacetophenone, p-methoxyacetophenone, 2-methyl[4-(methylthio)phenyl]-2-morpholino-1- Acetone, 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1- Ketone, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexyl benzophenone, etc.; quinines, such as hydrazine, 1, 4-naphthoquinone or the like; halogen compound, for example, 1,3,5-gin(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2-chlorophenyl) )-s-triazine, 1,3-bis(trichlorophenyl)-s-triazine, 2-chloroacetophenone, tribromomethylphenylhydrazine, ginseng (trichloromethyl)-s-three Pyrazine, 2,2,2-trifluoroethyl methacrylate, etc.; peroxides such as 贰-tertiary butyl peroxide and fluorenyl phosphine oxides, such as oxidized 2,4,6-trimethyl Benzylidene Phosphine and the like, but not limited Consists like.

In the photocrosslinkable resin composition of the present invention, the photoinitiator may preferably be 0.5 to 10 parts by weight, more preferably 2 to 5 parts by weight based on 100 parts by weight of the alkali-soluble resin. When the amount of the photoinitiator is less than 0.5 parts by weight or more than 10 parts by weight, the sensitivity and light transmittance of the film may be deteriorated.

Liquid repellency polymer (D)

The photocrosslinkable resin composition of the present invention contains a liquid repellent polymer (D). The liquid repellency polymer includes a fluoroalkyl acrylate represented by the following Chemical Formula 1: [Chemical Formula 1]

Wherein A is a fluoroalkyl group (Rf) or a perfluoropolyether (PFPE), and B is H, CH ₃ or a halogen atom.

In the present invention, when a functional material ink is applied, the liquid repellent polymer excludes the functional material ink from the region where the liquid repellent polymer exists, so that the functional material ink allows spontaneous diffusion to the lyophilic region . Therefore, the photocrosslinked resin composition containing the liquid repellency polymer can achieve fine patterning and liquid repellency without limiting the processing accuracy of the ink coater.

According to a specific embodiment of the invention, the liquid repellency polymer comprises a fluoroalkyl acrylate. In the photocrosslinkable resin composition of the present invention, the liquid repellency polymer is preferably used in an amount of from 0.5 to 10 parts by weight based on 100 parts by weight of the alkali-soluble resin. Less than 0.5 parts by weight of the liquid repellency polymer does not ensure a desired contact angle for propylene glycol monomethyl ether acetate (PGMEA). On the other hand, when the liquid repellent polymer content exceeds 10 parts by weight, it may remain in the developing portion.

Examples of the liquid repellency polymer include, but are not limited to, fluoroalkyl acrylate/methacrylic acid (MAA)/Rh-MA (manufactured by DAKIN). The compound is a copolymer of a fluoroalkyl acrylate and a methacrylic acid, wherein the fluoroalkyl acrylate moiety is responsible for the dynamic lyophobicity of the photoresist film, and the methacrylic acid moiety dominates the solubility of the alkaline developing solution and improves the crosslinking. Joint ability.

Solvent (E)

The photocrosslinkable resin composition of the present invention may further comprise a solvent (E) which maintains the solid content and viscosity. Any solvent known in the art can be used. Examples of the solvent (E) include: alcohols, For example, methanol, ethanol, propanol, isopropanol, ethylene glycol, etc.; ethers, such as tetrahydrofuran, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monoethyl ether, ethylene glycol single Ethyl ether; propylene glycol alkyl ether acetate, such as propylene glycol methyl ether acetate, propylene glycol diethyl ether acetate, propylene glycol propyl ether acetate, propylene glycol butyl ether acetate, etc.; ketones, such as acetone, methyl ethyl Ketone, cyclopentanone, cyclohexanone, 4-hydroxy-4-methyl-2-propanone, etc.; acetates such as ethyl acetate, butyl acetate, ethylene glycol monoethyl ether acetate, diethylene glycol Alcohol monoethyl ether acetate, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, etc.; and esters such as methyl acetate, ethyl ester, propyl or butyl ester, ethyl 2-hydroxypropionate or methyl ester , 2-hydroxy-2-methylpropionic acid ethyl ester, methyl hydroxyacetate, ethyl or butyl ester, ethyl lactate, propyl or butyl ester, methyl methoxyacetate, ethyl ester, propyl ester or butyl ester , methyl propionate, ethyl, propyl or butyl ester, methyl butoxide, ethyl, propyl or butyl ester, methyl 2-methoxypropionate, ethyl ester, propyl ester Butyl ester, methyl 2-ethoxypropionate, ethyl ester, propyl ester, butyl ester, methyl 3-methoxypropionate, ethyl ester, propyl or butyl ester, methyl 3-ethoxypropionate , ethyl ester, propyl ester, butyl ester, and methyl 3-butoxypropionate, ethyl ester, propyl ester or butyl ester, but not limited to them. These solvents may be used singly or in combination.

Preferred are diethylene glycol dimethyl ether, diethylene glycol diethyl ether and propylene glycol methyl ether acetate in view of solubility, reactivity with individual components, and film forming convenience.

The solvent is preferably used in an amount of 10 to 90 parts by weight based on 100 parts by weight of the alkali-soluble resin. Solvent levels above this range may not result in a smooth coating. The solvent in this range is provided, and the photocrosslinked resin composition is coated by, for example, a roll coater, a spin coater, a slit spin coater, a slit coater (die coater), or an ink jet printer. The application of the machine exhibits a high degree of coatability.

In addition to the above components, the photocrosslinkable resin composition of the present invention may further comprise an additive for enhancing specific functions without detracting from the object of the present invention, in view of the needs of those skilled in the art. Agents such as surfactants, lanthanide levelers, fillers and antioxidants. As regards the additives considered, they can be selected from materials widely used in the art.

Further, according to another aspect of the present invention, an insulating film formed by the photocrosslinking resin composition of the present invention is considered. The insulating film for the organic light-emitting diode can be formed by using the photocrosslinkable resin composition of the present invention in the following manner.

The photocrosslinked resin composition of the present invention is spread on a substrate and pre-baked to form a film. This coating can be obtained using a spin coater. The conditions of the pre-baking process vary depending on the composition component ratio, and can usually be performed at 100 to 120 ° C for 1 to 3 minutes using a hot plate. In this regard, the dielectric layer is adjusted to have a thickness of 3.0 to 4.0 μm. Next, the pre-baked coating is covered by a mask and exposed to UV radiation, and then unwanted portions are removed in the alkaline developing solution to form a pattern. The exposure is determined by the resolution. The developer is an inorganic base such as an aqueous solution of sodium hydroxide, potassium hydroxide, sodium citrate or ammonia. In particular, the development system is preferably carried out in a 2.38% aqueous solution of TMAH (tetramethylammonium hydroxide) for 60 to 180 seconds. Development can be carried out using a spray method or a dipping method.

Thereafter, the insulating film is completed by a post-baking process using a hot plate. The post-bake system is preferably carried out at 200 to 250 ° C for 30 to 60 minutes.

In addition to exhibiting excellent pattern development characteristics, light transmittance, and insulation resistance, the insulating film formed by the photocrosslinkable resin composition of the present invention is hydrophobic and has 40 for propylene glycol monomethyl ether acetate (PGMEA). ° or greater contact angle.

The insulating resistance of the photocrosslinked resin composition can be expressed by a dielectric constant of a coating layer of a photocrosslinked resin composition having a thickness of 2.0 to 4.0 μm. When having a dielectric constant of 3.5 or less, the film is suitable as an insulating film.

Further, the light transmittance of the insulating film according to the present invention is measured as a light transmittance of a coating layer of a photocrosslinked resin composition having a thickness of 2.0 to 4.0 μm at 550 nm. Preferably, the insulating film has a light transmittance of 90% or more. When the light transmittance under this condition is less than 90%, the insulating film is not suitable as a material for the bottom-emitting organic light-emitting diode.

According to still another aspect, the present invention relates to an organic light-emitting diode comprising the insulating film of the present invention. The production of the organic light-emitting diode is not particularly limited and can be carried out as exemplified below.

The organic light-emitting diode can be fabricated by depositing a transparent electrode, such as ITO, on a transparent substrate, coating the transparent substrate on which the transparent electrode is deposited, and then patterning the photoresist through exposure, development, etching, and lift-off. To obtain an insulating film. Next, a spacer is formed on the insulating film pattern. Then, an organic thin film is deposited to sequentially form an electron injecting layer, an electron transporting layer, a light emitting layer, a hole transporting layer, and a hole injecting layer, and then superposing the metal electrode layer on the hole injecting layer. Finally, the resulting structure was sealed with a sealant, and the module was assembled to obtain an organic light-emitting diode.

As described above, a composition comprising an alkali-soluble resin, an ethylenically unsaturated monomer, a photoinitiator, and a liquid-repellent polymer having a fluorine-containing alkyl acrylate is suspended in a specific amount of a solvent to prepare a according to the present invention. An example of a photocrosslinked resin composition of a specific example is shown. The photocrosslinkable resin composition of the present invention is highly soluble in an alkaline developing solution and crosslinked upon exposure. Therefore, the selective exposure causes the photocrosslinked resin composition to be selectively crosslinked, and the remaining portion which is not crosslinked is dissolved and removed by the alkaline developing solution. The unexposed portion is dissolved due to a change in solubility of the photocrosslinked resin composition caused by light.

That is, the photocrosslinked resin composition of the present invention is a negative photoresist. The composition is crosslinked by the action of the photoinitiator, the alkali-soluble resin and the ethylenically unsaturated monomer after exposure, so that the exposed portion is insoluble or almost insoluble in the alkaline developing solution, and the unexposed portion is Dissolved.

The invention may be better understood by the following examples, which are intended to be illustrative and not restrictive.

<Example 1> 1-1: Synthesis of alkali-soluble resin

A 2 liter double-layered flask with a stirrer, nitrogen inlet, dropping funnel and temperature controller was filled with 743.87 grams of propylene glycol monomethyl ether acetate (PGMEA) as the first solvent, while purging with nitrogen . In the flask, 91.565 g (0.25 mol) of the aromatic diamine bis-AP-AF was completely dissolved in the first solvent, followed by the addition of 111.0625 g (0.25 mol) of the aromatic anhydride 6FDA. The mixture was stirred at 23 ° C for 30 minutes to completely dissolve the 6FDA. The resulting solution had a solids content of 21% by weight. Polycondensation gave a polyamic acid resin of the following chemical formula 1-1 having a viscosity of 198 cps at 23 °C.

Where n is 34.

1-2: Preparation of photocrosslinking resin composition

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 3 hours: 80% by weight of the polyamic acid resin (room temperature, 198 cps) obtained in Example 1-1 as an alkali solubility Resin, 17.85% by weight of difunctional ethylene glycol (meth) acrylate (KAYARAD PEG400DA, NIPPON KAYAKU CO.) as ethylenically unsaturated monomer, 1% by weight of 2,2,2-trifluoroethyl methacrylic acid ester (MEHQ100) as a photoinitiator, 1% by weight of the fluorine-containing alkyl acrylate liquid repellent polymer ^{(OPTOACE TM, DAIKIN Industries, LTD} .), and 0.15 wt% silicon additive (BYK307) as a leveling agent.

<Example 2> 2-1: Synthesis of alkali-soluble resin

91.565 g (0.25 mol) of the aromatic diamine bis-AP-AF was completely dissolved in the same manner as in Example 1-1. Subsequently, 111.0625 g (0.25 mol) of aromatic dianhydride 6FDA was added, and completely dissolved by stirring at 23 ° C for 20 minutes. 39.55 grams (0.5 moles) of pyridine was added to the solution to help the extraction of the relevant resin during the chemical imidization to be in a stable state. After stirring at 80 ° C for 15 minutes, the stirred mixture was added to 3 liters of water to cause precipitation. The solid was filtered, ground to a fine powder, and dried in a vacuum oven at 100 ° C for 18 hours to obtain about 90 g of a powdered polyamine resin (weight average molecular weight: 49,800 g/mol) having the following chemical formula 1-2.

Where n is 78.

2-2: Preparation of photocrosslinking resin composition

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 3 hours: 56% by weight of the polyamic acid resin obtained in Example 2-1 (weight average molecular weight 49,800 g/mol) As an alkali-soluble resin, 35% by weight of a bifunctional ethylene glycol (meth) acrylate (KAYARAD PEG400DA, NIPPON KAYAKU CO.) as an ethylenically unsaturated monomer, 4% by weight of 2,2,2-trifluoroethyl as a photoinitiator, an acrylate-repellent 4 wt% of fluorine-containing alkyl methacrylate (MEHQ100) liquid polymer ^{(OPTOACE TM, DAIKIN Industries, LTD} .) and 1% by weight of silicon additive (BYK307) as a whole Flat agent.

<Comparative Example 1> 1-1: Synthesis of alkali-soluble resin

The alkali-soluble resin was synthesized in the same manner as in Example 1-1.

1-2: Preparation of photocrosslinking resin composition

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 3 hours: 81% by weight of the polyamic acid resin prepared in Comparative Example 1-1 (temperature at room temperature of 198 cps) As an alkali-soluble resin, 17.85% by weight of a bifunctional ethylene glycol (meth) acrylate (KAYARAD PEG400DA, NIPPON KAYAKU CO.) as an ethylenically unsaturated monomer, 1% by weight of 2,2,2-trifluoroethyl Methacrylate (MEHQ100) was used as a photoinitiator, and 0.15 wt% of an antimony additive (BYK307) was used as a leveling agent.

<Comparative Example 2> 2-1: Synthesis of alkali-soluble resin

The polyaminic acid resin was synthesized in the same manner as in Example 2-1 except that the dianhydride 6FDA was added in an amount less than 94.40 g (0.213 mol) of the Example 2-1, and in the aromatic diamine double-AP. -AF 91.57 g (0.25 mol) was completely dissolved and then stirred at 23 ° C for 30 minutes. The polyamic acid resin thus obtained had a viscosity of 43 cps at 23 °C. Then, the polyamic acid and acetic anhydride and pyridine (both of which acted as chemical imidizing agents) were stirred and mixed under the same conditions as in Example 2-1. Add 3 liters of water to the mixture to cause precipitation. The solid thus formed was filtered, ground to a fine powder, and dried in a vacuum oven at 100 ° C for 19 hours to obtain about 180 g of a powdered polyamine resin (weight average molecular weight: 20,000 g/mol).

2-2: Preparation of photocrosslinking resin composition

The same procedure as in Comparative Example 1-2 was repeated except that the polyamic acid resin synthesized in Comparative Example 2-1 was used as the alkali-soluble resin.

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 3 hours: 81% by weight of the polyamic acid resin prepared in Comparative Example 2-1 (temperature at room temperature of 198 cps) As an alkali-soluble resin, 17.85% by weight of a bifunctional ethylene glycol (meth) acrylate (KAYARAD PEG400DA, NIPPON KAYAKU CO.) as an ethylenically unsaturated monomer, 1% by weight of 2,2,2-trifluoroethyl Methacrylate (MEHQ100) was used as a photoinitiator, and 0.15 wt% of an antimony additive (BYK307) was used as a leveling agent.

<Comparative Example 3> 3-1: Synthesis of alkali-soluble resin

The polyamic acid resin was synthesized in the same manner as in Example 1-1 except

91.565 g (0.25 mol) of TFDB (2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl) having no hydroxyl group was dissolved as an aromatic diamine in place of bis-AP-AF. To the TFDB solution, 111.0625 g (0.25 mol) of aromatic dianhydride 6FDA was added, and the mixture was stirred at 23 ° C for 30 minutes to completely dissolve the 6FDA. The resulting solution had a solids content of 20% by weight. The polycondensation gave a poly-proline resin with a viscosity of 40 cps at 23 °C.

3-2: Preparation of photocrosslinking resin composition

The same procedure as in Example 1-2 was repeated except that the alkali-soluble resin synthesized in Comparative Example 3-1 was used. The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 3 hours: 81% by weight of the polyamic acid resin obtained in Comparative Example 3-1 (the viscosity at room temperature was 198 cps) ) as an alkali-soluble resin, 17.85% by weight of difunctional ethylene glycol (meth) acrylate (KAYARAD) PEG400DA, NIPPON KAYAKU CO.) as ethylenically unsaturated monomer, 1% by weight of 2,2,2-trifluoroethyl methacrylate (MEHQ100) as photoinitiator, and 0.15% by weight of cerium additive (BYK307) As a leveling agent.

<Comparative Example 4>

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 2 hours: 88% by weight of the polylysine synthesized in Example 1-1 as an alkali-soluble resin, 6 wt% in a stack A nitride-based photosensitive compound ((1-[1-(4-hydroxyphenyl)isopropyl)-4-[1,1-bis(4-hydroxyphenyl)ethyl)benzene)-1,2 -naphthoquinonediazide-5-sulfonate), 1.5% by weight sensitivity enhancer (1-[1-(4-hydroxyphenyl)isopropyl)-4-[1,1-bis(4 - hydroxyphenyl) ethyl] benzene), 4% by weight of the fluorine-containing alkyl acrylate liquid repellent polymer ^{(OPTOACE TM, DAIKIN Industries, LTD} ), and 0.5 wt% silica as an additive leveler.

<Comparative Example 5>

The photocrosslinked resin composition was obtained by stirring the following mixture at 23 ° C for 2 hours: 12% by weight of the polylysine synthesized in Example 2-1, and 6% by weight of the diazide Photosensitive compound of the substrate ((1-[1-(4-hydroxyphenyl)isopropyl)-4-[1,1-bis(4-hydroxyphenyl)ethyl)benzene)-1,2-naphthoquinone Diazide-5-sulfonate), 76% by weight solvent (propylene glycol monomethyl ether acetate), 1.5% by weight sensitivity enhancer (1-[1-(4-hydroxyphenyl)isopropyl) 4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene), 4% by weight of the fluorine-containing alkyl acrylate liquid-repellent polymer ^{(OPTOACE TM, DAIKIN Industries, LTD} .), and 0.5 The % by weight 矽 additive acts as a leveling agent.

The photocrosslinkable resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 were tested for film forming ability and characteristics in the following Test Examples 1 to 6, and the results are summarized in Table 1 below.

<Test Example 1: Measuring Contact Angle>

Each of the photocrosslinkable resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 was applied to an ITO substrate by spin coating to form a 3.0 μm thick coating layer. The coating was prebaked on a hot plate at 100 ° C for 100 seconds and dried to a coating thickness of 3.0 ± 0.05 μm. The substrate was subjected to UV overall exposure at 100 mJ/cm ² and then developed in a 2.38% TMAH alkaline developing solution for 80 seconds, followed by washing for 20 seconds. The post-bake was performed on a hot plate at 230 ° C for 60 minutes, after which the contact angle of the residual coating film to PGMEA was measured using a Kruss DSA100.

<Test Example 2: Resolution>

Each of the photocrosslinkable resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 was applied to an ITO substrate by spin coating to form a 3.0 μm thick coating layer. The coating was prebaked on a hot plate at 100 ° C for 100 seconds and dried to a coating thickness of 3.0 ± 0.05 μm. The substrate was exposed to UV at 100 mJ/cm ² under a mask of various pattern sizes (2 to 100 μm), and then developed in a 2.38% TMAH alkaline developing solution for 80 seconds, followed by washing for 20 seconds. The pattern size of the residual coating film thus patterned was measured under an optical microscope.

<Test Example 3: Light transmittance>

After prebaking, the coating films formed by the photocrosslinked resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 were developed without patterning. Thereafter, the UV transmittance of the films at 550 nm was measured. Subsequently, the films were heat-treated at 250 ° C for 1 hour without discoloration, and the light transmittance was measured to determine whether the films were yellowed.

<Test Example 4: Dielectric constant>

Each of the photocrosslinkable resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 was applied to an ITO substrate by spin coating to form a 3.0 μm thick coating layer. The coating was prebaked on a hot plate at 100 ° C for 100 seconds and dried to a coating thickness of 3.0 ± 0.05 μm. The substrate was exposed to UV at 100 mJ/cm ² under a reticle, then developed for 2.3 seconds in a 2.38% TMAH alkaline developing solution, washed for 40 seconds, and then heated on a hot plate at 230 ° C for 1 hour. The insulating film thus obtained was 2.4 μm thick. The metal electrode (AI) was deposited on the insulating film at a thickness of 2,000 Å (thermal evaporator model E306), and then the dielectric constant of the insulating film was measured using a precision impedance analyzer (Model: 4294A, HP).

<Test Example 5: Outgassing>

The photocrosslinked resin compositions prepared in Examples 1 and 2 and Comparative Examples 1 to 5 were dried at 150 ° C for 5 hours to evaporate the solvent. Subsequently, 0.5 mg of each sample was placed in a GC-MS bottle and placed in a furnace at 280 ° C for 30 minutes, and the outgas during the period was collected. The total area of the outgassing peaks read by the pyrolyzer GC-MS was calculated relative to the sample of Example 2.

<Test Example 6: Residue generation>

The pattern was formed in the same manner as in Test Example 2 for resolution measurement. Examination was performed by scanning electron microscopy (SEM) to see if the 8-μm pattern was developed and no residue was formed. The results are summarized in Table 1 below, wherein the mark 'X' indicates the absence of a residue, the mark '△' indicates the presence of a local residue, and the mark '○' indicates the presence of a residue. The pattern resolution image formed by the photocrosslinked resin composition of Example 1 is shown in Fig. 1 .

As can be understood from the data in Table 1, the insulating film formed of the compositions of Examples 1 and 2 is equivalent to or larger than the comparative example in terms of residue formation, light transmittance, dielectric constant, and outgas. An insulating film prepared from 1 to 5. Further, only the insulating films of Examples 1 and 2 showed a contact angle of 40° or more for propylene glycol monomethyl ether acetate (PGMEA). As can be seen in Figure 1, no residue was observed at the boundary between the exposed and unexposed regions. With respect to the insulating films of the fluorine-free alkyl acrylate-free liquid repellent prepared in Comparative Examples 1 and 2, the contact angle was too small to be measured. The film of Comparative Example 3 did not detect development characteristics in which the monomer free of OH was polycondensed. The photodegradable resin compositions of Comparative Examples 4 and 5, although including a liquid-repellent polymer of a fluorine-containing alkyl acrylate, did not show an increase in contact angle.

As described above, the photocrosslinkable resin composition of the present invention allows formation of a highly fine circuit, exhibits excellent light transmittance, and low generation of outgassing under high temperature conditions after solvent removal.

Moreover, the photocrosslinkable resin composition of the present invention can be crosslinked to form an insulating film having a low dielectric constant and having a contact angle of 40 or more with respect to propylene glycol monomethyl ether acetate (PGMEA).

Furthermore, the photocrosslinkable resin composition of the present invention can be used as a negative photoresist for use in fabricating OLEDs, which exhibit high contrast and thus allow for the materialization of high definition patterns.

While the preferred embodiment of the present invention has been described by way of example, it is understood that the various modifications, additions and substitutions are possible, and the scope and spirit of the invention disclosed in the appended claims.

Claims (16)

A photocrosslinking resin composition comprising an alkali-soluble resin (A), an ethylenically unsaturated monomer (B), a photoinitiator (C), and a liquid-repellent polymer (D), the alkali-soluble resin ( A) is a polylysine having a repeating unit represented by the following Chemical Formula 2, and the liquid-repellent polymer (D) contains a fluoroalkyl acrylate represented by the following Chemical Formula 1: Wherein A is a fluoroalkyl group (Rf) or a perfluoropolyether (PFPE) group, and B is H, CH ₃ or a halogen atom; Wherein R ₁ and R ₂ may be the same or different, each independently being a di- to octavalent organic group containing two or more carbon atoms, and R ₃ and R ₄ may be the same or different, individually independent The ground is an organic group having 1 to 12 carbon atoms, a hydrogen atom or a halogen atom having a hydroxyl group, x is an integer of 0 to 2, and y is an integer of 0 to 4, provided that x+y>0, z is an integer from 0 to 2, and n is an integer from 10 to 200. The photocrosslinking resin composition of claim 1, wherein R ₁ and R ₂ are the same or different and are preferably individually independently a biphenyl group containing a C 2 to C 8 fluoroalkyl group. The photocrosslinking resin composition of claim 1, wherein the composition contains 5 to 80 parts by weight of the ethylenically unsaturated monomer (B), 0.5 based on 100 parts by weight of the alkali-soluble resin (A). To 10 parts by weight of the photoinitiator (C), and 0.5 to 10 parts by weight of the fluoroalkyl acrylate-containing liquid repellent polymer (D). The photocrosslinking resin composition of claim 1, wherein the alkali-soluble resin is prepared by polymerizing an aromatic diamine and an aromatic dianhydride in a first solvent. The photocrosslinking resin composition of claim 4, wherein the alkali-soluble resin is prepared by polymerizing an aromatic diamine and an aromatic dianhydride into a poly-proline resin in a first solvent, or by The two solvents are obtained by precipitating the polyamide resin, filtering the precipitate, and drying the filtrate. The photocrosslinking resin composition of claim 4, wherein the aromatic diamine is at least one selected from the group consisting of 2,2-bis(3-amino-4-hydroxybenzene) Hexafluoropropane (bis-AP-AF), 2,2-bis[4-(4-aminophenoxy)-phenyl]propane (6HMDA), 2,2 ' -bis(trifluoromethyl) -4,4 ' -diaminobiphenyl (2,2 ' -TFDB), 3,3 ' -bis(trifluoromethyl)-4,4 ' -diaminobiphenyl (3, 3 ' -TFDB), 4,4 ' -bis(3-aminophenoxy)diphenylphosphonium (DBSDA), bis(3-aminophenyl)phosphonium (3DDS), bis(4-aminobenzene)碸(4DDS), 1,3-bis(3-aminophenoxy)benzene (APB-133), 1,4-bis(4-aminophenoxy)benzene (APB-134), 2 , 2 ' -bis[3(3-aminophenoxy)phenyl]hexafluoropropane (3-BDAF), 2,2 ' -bis[4(4-aminophenoxy)phenyl]hexafluoro Propane (4-BDAF) and oxydiphenylamine (ODA). The photocrosslinking resin composition of claim 4, wherein the aromatic dianhydride is at least one selected from the group consisting of 2,2-bis(3,4-dicarboxyphenyl) Hexafluoropropane dianhydride (6FDA), 4-(2,5-dionetetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dianhydride (TDA), 4, 4 ' -(4,4 ' -isopropylidenediphenoxy) bis(phthalic anhydride) (HBDA), 3,3 ' -(4,4 ' -oxyphthalic dianhydride) (ODPA) and 3,4,3 ', 4' - biphenyl tetracarboxylic dianhydride (BPDA). The photocrosslinking resin composition of claim 4, wherein the first solvent is at least one selected from the group consisting of: m-cresol, N-methyl-2-pyrrolidone (NMP) , dimethylformamide (DMF), dimethylacetamide (DMAc), dimethyl hydrazine (DMSO), acetone, propylene glycol monomethyl ether acetate (PGMEA), and diacetic acid. The photocrosslinking resin composition of claim 5, wherein the second solvent is at least one selected from the group consisting of water, alcohols, ethers, and ketones. The photocrosslinked resin composition of claim 1, wherein the alkali-soluble resin has a weight average molecular weight of from 10,000 to 40,000 g/mol. The photocrosslinked resin composition of claim 1, wherein the ethylenically unsaturated monomer is an acrylic monomer having at least one ethylenically unsaturated bond. An insulating film formed of the photocrosslinked resin composition of claim 1. The insulating film of claim 12, which has a light transmittance of 90% or more. The insulating film of claim 12, which has a dielectric constant of 3.5 or less. The insulating film of claim 12, which exhibits a contact angle of 40° or more for propylene glycol monomethyl ether acetate (PGMEA). An organic light emitting diode comprising the insulating film of claim 12.