JP6391491B2 - Organic thin film element sealant for electrostatic coating, resin protective film, electronic device, and method for manufacturing electronic device - Google Patents

Description

The present invention relates to a curable resin composition for electrostatic coating that can efficiently form a uniform thin film under atmospheric pressure and can suppress the generation of outgas. Moreover, this invention relates to the manufacturing method of the resin protective film which uses this curable resin composition for electrostatic coating, an electronic device, and an electronic device.

In recent years, research on electronic devices using organic thin film elements such as organic electroluminescence elements and organic thin film solar cell elements has been advanced. The organic thin film element can be easily produced by vacuum deposition, solution coating, or the like, and thus has excellent productivity.

The organic electroluminescence element has a thin film structure in which an organic light emitting material layer is sandwiched between a pair of electrodes facing each other. When electrons are injected from one electrode into the organic light emitting material layer and holes are injected from the other electrode, electrons and holes are combined in the organic light emitting material layer to perform self-light emission. A device using an organic electroluminescence element has the advantages that it is more visible than a liquid crystal display device that requires a backlight, can be made thinner, and can be driven by a DC low voltage. It has attracted attention as a next-generation display.

Organic thin-film solar cell elements are superior to solar cells using inorganic semiconductors in terms of cost, large area, ease of manufacturing processes, and the like, and various configurations have been proposed. Specifically, for example, Non-Patent Document 1 discloses an organic solar cell element using a laminated film of phthalocyanine copper and a perylene dye.

These organic thin film elements have a problem that when the organic layer and the electrode are exposed to the outside air, the performance is rapidly deteriorated. Therefore, in order to improve stability and durability, it is indispensable to seal the organic thin film element and shield it from moisture and oxygen in the atmosphere.
As a method for sealing an organic thin film element, conventionally, a method of sealing with a sealing can provided with a water-absorbing agent is generally used. However, in the method of sealing with a sealing can, it is difficult to reduce the thickness of the electronic device. Therefore, development of a method for sealing an organic thin film element that does not use a sealing can is being promoted.

Patent Document 1 discloses a method of sealing an organic layer and an electrode of an organic thin film element with a laminated film of a resin film formed by a CVD method and a silicon nitride (SiN _x ) film. Here, the resin film has a role of preventing pressure on the organic layer and the electrode due to internal stress of the silicon nitride film.

In the method of sealing with a silicon nitride film disclosed in Patent Document 1, the organic thin film element is formed when the silicon nitride film is formed due to unevenness on the surface of the organic thin film element, adhesion of foreign matters, generation of cracks due to internal stress, or the like. May not be completely covered with a film. If the coating with the silicon nitride film is incomplete, moisture will enter the organic layer through the silicon nitride film.
As a method for preventing moisture from entering the organic layer, Patent Document 2 discloses a method of alternately depositing an inorganic material film and a resin film.

However, the method disclosed in Patent Document 2 requires a vacuum apparatus to form a resin film under reduced pressure, and also forms a film by heating and vaporizing a material to be a resin film. The material forming the film is required to have heat resistance and volatility.

JP 2000-223264 A JP 2005-522891 A

Applied Physics Letters (1986, Vol. 48, P. 183)

An object of this invention is to provide the curable resin composition for electrostatic coating which can form a uniform thin film efficiently under atmospheric pressure, and can suppress generation | occurrence | production of outgas. Moreover, an object of this invention is to provide the manufacturing method of the resin protective film which uses this curable resin composition for electrostatic coating, an electronic device, and an electronic device.

The present invention provides a curable compound for electrostatic coating having a boiling point of less than 420 ° C. and / or a molecular weight of less than 340, and a liquid curable compound at 25 ° C., and a polymerization initiator and / or a thermosetting agent. It is a resin composition.
The present invention is described in detail below.

The present inventor studied using an electrostatic coating method in order to efficiently form a uniform thin film without requiring heating or a vacuum apparatus during coating. FIG. 1 is a schematic view showing an example of a process for producing a thin film by an electrostatic coating method.
As shown in FIG. 1, the electrostatic coating method is a method in which the coating liquid particles 3 charged by discharging the coating liquid 2 from the nozzle 1 to which a voltage is applied are charged to the opposite electrode to the nozzle 1. This is a method of forming a coating film by depositing on the coating material 4. In the electrostatic coating method, the coating liquid discharged from the nozzle is charged by discharging the coating liquid from the nozzle to which the voltage is applied in this way. In FIG. 1, electrostatic coating is performed by spraying the coating liquid 2 charged on the plus side onto the coating surface of the coating material 4 electrically connected to the minus side. You may spray the application liquid electrically charged to the minus side on the application surface. As shown in FIG. 1, the coating liquid 2 discharged from the nozzle 1 is electrically repelled between droplets (coating liquid particles 3), the volume is reduced due to the volatilization of the components, and the surface charge is reduced. By increasing the number, self-splitting (Rayleigh splitting) is repeated to form minute droplets. For this reason, in the electrostatic coating method, the coating liquid can be uniformly applied with a very thin film thickness by properly setting conditions such as the applied voltage, the flow rate of the coating liquid, and the distance from the nozzle to the surface to be coated. Can do. That is, the electrostatic coating method is superior to the ink jet method in that the coating liquid can be divided into smaller droplets than when ejected by electrostatic repulsion, and a mask is placed on the coated surface. Thus, it can be said that it is superior to the spin coating method in that a coating film having a desired shape can be formed.
The present inventor has studied to produce a uniform and thin resin film by such an electrostatic coating method, but depending on the material used as the coating liquid, a uniform thin film cannot be formed or a large amount of outgas is generated. There was a problem to do. Therefore, as a result of further investigation, the present inventor can efficiently form a uniform thin film at atmospheric pressure by an electrostatic coating method by using a curable resin composition containing a specific curable compound as a coating liquid. It was found that the generation of outgas could be suppressed and the present invention was completed.

The curable resin composition for electrostatic coating of the present invention has a boiling point of less than 420 ° C. and / or a molecular weight of less than 340, and a liquid curable compound at 25 ° C. (hereinafter referred to as “the curable compound according to the present invention”). "). When electrostatic coating is performed using the curable compound according to the present invention, the droplets are Rayleigh split due to the increase in surface charge accompanying the volatilization of the components and become microscopic droplets. It can be formed efficiently. Among these, it is preferable to use a curable compound having a boiling point of less than 420 ° C., a molecular weight of less than 340, and a liquid at 25 ° C.
In the present specification, the “boiling point” means a boiling point at 760 mmHg.

When a compound having a boiling point of less than 420 ° C. is used as the curable compound according to the present invention, it is preferable to use a compound having a boiling point of less than 380 ° C., and a compound having a boiling point of less than 340 ° C. from the viewpoint of electrostatic coating efficiency. Is more preferable. Moreover, since formation of the film | membrane by an electrostatic coating method will become difficult when a boiling point is too low, it is preferable that the boiling point of the curable compound concerning this invention is 80 degreeC or more.
When using a compound having a molecular weight of less than 340 as the curable compound according to the present invention, it is preferable to use a compound having a molecular weight of less than 300, and more preferable to use a compound having a molecular weight of less than 260, from the viewpoint of electrostatic coating efficiency. . Moreover, since formation of the film | membrane by an electrostatic coating method will become difficult when molecular weight is too low, it is preferable that the molecular weight of the curable compound concerning this invention is 100 or more.

The curable compound according to the present invention is preferably at least one selected from the group consisting of an epoxy compound, an oxetanyl compound, and a vinyl ether compound. Since the epoxy compound, the oxetanyl compound, and the vinyl ether compound are cationically polymerizable compounds, the curable resin composition for electrostatic coating obtained using these is obtained with little curing shrinkage at the time of curing. The resin film is excellent in adhesiveness with an inorganic material film or the like.
When at least one selected from the group consisting of an epoxy compound, an oxetanyl compound, and a vinyl ether compound is used as the curable compound according to the present invention, it is preferable to use a cationic polymerization initiator and / or a thermosetting agent described later. .

Examples of the epoxy compound having a boiling point of less than 420 ° C. and / or a molecular weight of less than 340 and liquid at 25 ° C. include monoglycidyl ether, diglycidyl ether, and alicyclic epoxy resins.

Examples of the monoglycidyl ether include butyl glycidyl ether (molecular weight 130, boiling point 165 ° C.), phenyl glycidyl ether (molecular weight 150, boiling point 245 ° C.), 2-ethylhexyl glycidyl ether (molecular weight 186, boiling point 120 ° C.), secondary butylphenol mono Examples thereof include glycidyl ether (molecular weight 260, boiling point 300 ° C.) and cresyl glycidyl ether (molecular weight 164, boiling point 270 ° C.).
Examples of the diglycidyl ether include 1,6-hexanediol diglycidyl ether (molecular weight 230, boiling point 300 ° C.), 1,4-butanediol diglycidyl ether (molecular weight 202, boiling point 266 ° C.), neopentyl glycol diglycidyl. And ether (molecular weight 206, boiling point 290 ° C.).
Examples of the alicyclic epoxy resin include alicyclic epoxy resins having a 4- to 7-membered cyclic aliphatic group. Specific examples include 1,2: 8,9-diepoxy limonene (molecular weight 140). , Boiling point 230 ° C.), 4-vinylcyclohexene monooxide (molecular weight 124, boiling point 169 ° C.), dicyclohexyl-3,3′-diepoxide (molecular weight 194, boiling point 300 ° C.), bis (2,3-epoxycyclopentyl) ether (molecular weight) 182, boiling point less than 340 ° C), 1,1'-bi (2,3-epoxycyclohexane) (molecular weight 194, boiling point less than 340 ° C), vinylcyclohexene dioxide (molecular weight 140, boiling point 250 ° C), methylated vinylcyclohexene Oxide, dicyclopentadiene dioxide (molecular weight 164, boiling point less than 340 ° C), 1-vinyl 3,4-epoxycyclohexane (molecular weight 124, boiling point 169 ° C.), 1-epoxyethyl-3,4-epoxycyclohexane (molecular weight 140, boiling point 230 ° C.), 3 ′, 4′-epoxycyclohexylmethyl-3,4-epoxy Examples include cyclohexanecarboxylate (molecular weight 252 and boiling point less than 340 ° C.), 4,4′-bi (1,2-epoxycyclohexane) (molecular weight 194, boiling point 290 ° C.) and the like.

Examples of the oxetanyl compound include 3-ethyl-3- (phenoxymethyl) oxetane (molecular weight 192, boiling point 290 ° C.), 3-ethyl-3-hydroxymethyloxetane (molecular weight 116, boiling point 250 ° C.), 3-ethyl- 3-hydroxybutyloxetane (molecular weight 158, boiling point 290 ° C.), 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane (molecular weight 228, boiling point 270 ° C.), di (1-ethyl (3-oxetanyl)) methyl Examples include ether (molecular weight 214, boiling point 270 ° C.), 3-ethyl-3-((3- (triethoxysilyl) propoxy) methyl) oxetane (molecular weight 320, boiling point 320 ° C.), and the like. These oxetanyl compounds may be used alone or in combination of two or more.

Examples of the vinyl ether compound include benzyl vinyl ether (molecular weight 134, boiling point 184 ° C.), cyclohexanedimethanol monovinyl ether (molecular weight 170, boiling point 111 ° C.), dicyclopentadiene vinyl ether (molecular weight 176, boiling point 230 ° C.), 1,4- Butanediol divinyl ether (molecular weight 142, boiling point 168 ° C.), cyclohexanedimethanol divinyl ether (molecular weight 196, boiling point 104 ° C.), diethylene glycol divinyl ether (molecular weight 158, boiling point 199 ° C.), triethylene glycol divinyl ether (molecular weight 202, boiling point 230 ° C) and the like. These vinyl ether compounds may be used alone or in combination of two or more.

The curable compound concerning this invention may contain other cationically polymerizable compounds other than the said epoxy compound, oxetanyl compound, and a vinyl ether compound.
Examples of the other cationic polymerizable compound include, among compounds having a cationic polymerizable functional group such as at least one hydroxyl group, episulfide group, and ethyleneimine group in the molecule, a boiling point of less than 420 ° C. and / or a molecular weight. It is less than 340 and is liquid at 25 ° C.

The curable compound according to the present invention may contain a (meth) acrylic compound.
Examples of (meth) acrylic compounds having a boiling point of less than 420 ° C. and / or a molecular weight of less than 340 and liquid at 25 ° C. include glycidyl acrylate (molecular weight 128, boiling point 180 ° C.), glycidyl methacrylate (molecular weight 142, Boiling point 189 ° C.), 1,6-hexanediol diacrylate (molecular weight 226, boiling point 295 ° C.), 1,6-hexanediol dimethacrylate (molecular weight 254, boiling point 350 ° C.), 1,9-nonanediol diacrylate (molecular weight 268) , Boiling point 342 ° C.), 1,9-hexanediol dimethacrylate (molecular weight 296, boiling point 390 ° C.), dicyclopentenyl acrylate (molecular weight 204, boiling point 250 ° C.), dicyclopentenyl methacrylate (molecular weight 218, Boiling point 270 ° C.), dicyclopentenyloxyethyl Acrylate (molecular weight 248, boiling point 300 ° C.), dicyclopentanyl acrylate (molecular weight 206, boiling point 270 ° C.), dicyclopentanyl methacrylate (molecular weight 220, boiling point 280 ° C.), benzyl acrylate (molecular weight) 162, boiling point 210 ° C.), benzyl methacrylate (molecular weight 176, boiling point 230 ° C.), trimethylolpropane trimethacrylate (molecular weight 338, boiling point 400 ° C.), 1,12-dodecanediol diacrylate (molecular weight 310, boiling point 380 ° C.), 1 , 12-dodecanediol dimethacrylate (molecular weight 338, boiling point 410 ° C.), lauryl acrylate (molecular weight 240, boiling point 315 ° C.), lauryl methacrylate (molecular weight 254, boiling point 320 ° C.) and the like. These (meth) acrylic compounds may be used alone or in combination of two or more.
In the present specification, the “(meth) acryl” means acryl or methacryl, and the “(meth) acryl compound” means a compound having a (meth) acryloyl group. The term “(meth) acryloyl group” means an acryloyl group or a methacryloyl group.

When using the said (meth) acrylic compound as a curable compound concerning this invention, it is preferable to use a radical polymerization initiator as a polymerization initiator mentioned later.

The curable compound according to the present invention may be a combination of a polythiol compound having two or more thiol groups in one molecule and a polyene compound having two or more carbon-carbon double bonds in one molecule. Good. When the polythiol compound and the polyene compound are used in combination as the curable compound according to the present invention, both the polythiol compound and the polyene compound have a boiling point of less than 420 ° C. and / or a molecular weight of less than 340, and It is liquid at 25 ° C.

The molecular weight ratio between the polythiol compound and the polyene compound is preferably 1: 0.5 to 1: 1.8. When the molecular weight ratio is out of the above range, the difference in electrostatic coating efficiency between the polythiol compound and the polyene compound increases, and the unreacted monomer may easily remain. The molecular weight ratio between the polythiol compound and the polyene compound is more preferably 1: 0.6 to 1: 1.5, and still more preferably 1: 0.7 to 1: 1.3.

As the polythiol compound, an ester obtained by a reaction between a mercaptocarboxylic acid and a polyhydric alcohol is preferably used.
Examples of the ester obtained by the reaction of the mercaptocarboxylic acid and the polyhydric alcohol include trimethylolpropane tris (3-mercaptopropionate) (molecular weight 356, boiling point 350 ° C.), butanediol bisthioglycolate (molecular weight 238). , Boiling point 300 ° C.), ethylene bis (mercaptoacetate) (molecular weight 210, boiling point 310 ° C.) and the like. Of these, butanediol bisthioglycolate is preferred because of its high electrostatic coating efficiency and high curability. Examples of other polythiol compounds include 1,10-dodecanedithiol (molecular weight 206, boiling point 171 ° C.).
These polythiol compounds may be used independently and 2 or more types may be used in combination.

As the polyene compound, a polyene compound having an aromatic ring is preferably used. By using a polyene compound having an aromatic ring, the resin film obtained by curing the curable resin composition for electrostatic coating of the present invention has excellent heat resistance. Specifically, the glass transition temperature rises and a highly reliable resin film at a high temperature is obtained.
Examples of the polyene compound having an aromatic ring include diallyl phthalate (molecular weight 246, boiling point 310 ° C.), diallyl isophthalate (molecular weight 246, boiling point 330 ° C.), and diallyl diphenate (molecular weight 322, boiling point 350 ° C.). It is done. Of these, diallyl phthalate is preferred because of its low viscosity and high electrostatic coating efficiency. These polyene compounds having an aromatic ring may be used alone or in combination of two or more.

When the polyene compound contains the polyene compound having the aromatic ring, the content ratio of the polyene compound having the aromatic ring is 50% by weight or more based on the whole polyene compound from the viewpoint of heat resistance of the resulting resin film. It is preferable that

Further, as the polyene compound, a polyene compound having no aromatic ring can also be used. Examples of the polyene compound having no aromatic ring include triallyl isocyanurate (molecular weight 249, boiling point 305 ° C.), trimethallyl isocyanurate (molecular weight 291; boiling point 350 ° C.), pentaerythritol triallyl ether (molecular weight 256, boiling point). 300 ° C.). Of these, triallyl isocyanurate is preferred because of its low viscosity and high curability. These polyene compounds not having an aromatic ring may be used alone or in combination of two or more.

Furthermore, as the polyene compound, bifunctional or higher functional compounds among the above-described (meth) acrylic compounds, the above-described vinyl ether compounds, allyl ether compounds, and the like are also preferably used.

The blending ratio of the polythiol compound and the polyene compound in the curable resin composition for electrostatic coating of the present invention is not particularly limited, but is polythiol compound: polyene compound = 25: 75 to 68:32 by weight ratio. It is preferable to blend as described above.
Further, the molar ratio between the thiol group of the polythiol compound and the carbon-carbon double bond of the polyene compound is thiol group: carbon-carbon double bond = 1: 0.4 to 1: 2.5. It is preferable to do. When the number of moles of thiol group exceeds 2.5 times the number of moles of carbon-carbon double bonds, or when the number of moles of thiol group is less than 0.4 times the number of moles of carbon-carbon double bonds Unreacted monomers are likely to remain, and outgassing may occur, or a resin film having uniform physical properties may not be obtained efficiently by the electrostatic coating method. The polythiol compound and the polyene compound are more preferably blended so that thiol group: carbon-carbon double bond = 1: 0.5 to 1: 2, and blended so as to be close to 1: 1. More preferably.

When using the said polythiol compound and the said polyene compound in combination, it is preferable to use a radical polymerization initiator as a polymerization initiator mentioned later.

The curable resin composition for electrostatic coating of the present invention has a boiling point of 420 ° C. or higher, a molecular weight of 340 or higher, and a liquid curable compound at 25 ° C. in addition to the curable compound according to the present invention. And at least one selected from the group consisting of a curable compound that is solid at 25 ° C. and a non-curable compound that is solid at 25 ° C.
In the present specification, the above “non-curable compound” means a compound that constitutes a coating film and does not react with the curable compound according to the present invention during the curing reaction of the curable compound according to the present invention. To do.

As the curable compound having a boiling point of 420 ° C. or higher, a molecular weight of 340 or higher, and a liquid at 25 ° C., for example, a bisphenol type epoxy compound such as a bisphenol A type epoxy compound or a bisphenol F type epoxy compound, Alcohol-type epoxy compounds such as hydrogenated bisphenol A-type epoxy compounds and hydrogenated bisphenol F-type epoxy compounds, halogenated epoxy compounds such as brominated epoxy compounds, naphthalene-type epoxy compounds, aliphatic epoxy compounds, and alicyclic epoxy compounds Cyclic ring type epoxy compound, polyfunctional epoxy compound, biphenyl type epoxy compound, glycidyl ether type epoxy compound, glycidyl ester type epoxy compound, glycidyl amine type epoxy compound, rubber modified epoxy compound, urethane modified Epoxy compounds such as poxy compounds, epoxidized polybutadiene, epoxidized styrene-butadiene-styrene block copolymers, epoxy group-containing polyester compounds, epoxy group-containing polyurethane compounds, epoxy group-containing acrylic compounds, oxetanylsilsesquioxane, phenol novolac oxetane And allyl compounds such as oxetane compounds. Of these, ε-caprolactone-modified 3 ′, 4′-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (molecular weight 366, boiling point 420 ° C. or higher) is preferable.

Examples of the curable compound that is solid at 25 ° C. include novolak-type epoxy compounds such as phenol novolak-type epoxy compounds and cresol novolak-type epoxy compounds, hydrogenated bisphenol A-type epoxy compounds, 1,4-bis ((((3 -Ethyl-3-oxetanyl) methoxy) methyl) benzene and the like. Of these, 1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol is preferable.

Examples of the non-curable compound that is solid at 25 ° C. include thermoplastic resins such as phenoxy resin, polystyrene, acrylic resin, and polyester. Of these, phenoxy resin is preferred.

The curable resin composition for electrostatic coating of the present invention preferably contains a curable compound having an alkylene oxide structure in the main chain. By containing a curable compound having an alkylene oxide structure in the main chain, the charge can easily move and the antistatic property can be improved.
The curable compound having an alkylene oxide structure in the main chain may be a curable compound according to the present invention, or other curable compounds, that is, a boiling point of 420 ° C. or higher and a molecular weight of 340 or higher. It may be a curable compound that is liquid at 25 ° C. or a curable compound that is solid at 25 ° C., but is preferably a curable compound according to the present invention.

Examples of the curable compound having an alkylene oxide structure in the main chain include, for example, a (meth) acrylic compound having an alkylene oxide structure in the main chain, an epoxy compound having an alkylene oxide structure in the main chain, and an alkylene oxide structure in the main chain. It is preferably an oxetanyl compound and at least one compound selected from the group consisting of vinyl ether compounds having an alkylene oxide structure in the main chain, or a lithium salt, sodium salt, iodonium salt, or tetraalkylammonium salt thereof. .
An alkylene oxide structure containing an oxygen atom contained in a polymerizable group such as a (meth) acryloyl group, an epoxy group, an oxetanyl group, or a vinyl ether group is not included in the alkylene oxide structure of the main chain.

Examples of the (meth) acrylic compound having an alkylene oxide structure in the main chain include diacrylates such as diethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, and polypropylene glycol diacrylate, ethylene Examples include dimethacrylates such as glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, and polyethylene glycol dimethacrylate.
Examples of the oxetanyl compound having an alkylene oxide structure in the main chain include 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, di (1-ethyl (3-oxetanyl)) methyl ether, and the like.
Examples of the epoxy compound having an alkylene oxide structure in the main chain include ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 2,2-dimethyl-1,3-propanediol diglycidyl ether, diethylene glycol diglycidyl ether, Examples include ethylene glycol diglycidyl ether, tetraethylene glycol diglycidyl ether, and hexaethylene glycol diglycidyl ether.
Examples of vinyl ether compounds having an alkylene oxide structure in the main chain include ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, cyclohexane dimethanol divinyl ether, ethylene oxide-added trimethylolpropane trivinyl ether, Propylene oxide-added trimethylolpropane trivinyl ether, ethylene oxide-added ditrimethylolpropane tetravinyl ether, propylene oxide-added ditrimethylolpropane tetravinyl ether, ethylene oxide-added pentaerythritol tetravinyl ether, propylene oxide-added pentaerythritol tetravinyl ether Le, ethylene oxide adduct of dipentaerythritol hexavinyl ether, and propylene oxide adduct of dipentaerythritol hexavinyl ether.
Among these, an epoxy compound having an alkylene oxide structure in the main chain is preferable because of high heat resistance.

As for the content ratio of the curable compound having an alkylene oxide structure in the main chain, a preferable lower limit is 1 part by weight and a preferable upper limit is 50 parts by weight in 100 parts by weight of the entire curable compound. When the content of the curable compound having an alkylene oxide structure in the main chain is less than 1 part by weight, a problem may occur in the device due to charging of the obtained coating film. When the content of the curable compound having an alkylene oxide structure in the main chain exceeds 50 parts by weight, the resulting composition may have insufficient curability. A more preferable lower limit of the content of the curable compound having an alkylene oxide structure in the main chain is 5 parts by weight.

The curable resin composition for electrostatic coating of the present invention contains a polymerization initiator and / or a thermosetting agent.
As described above, when the curable compound according to the present invention is at least one selected from the group consisting of an epoxy compound, an oxetanyl compound, and a vinyl ether compound, a cationic polymerization initiator and / or a thermosetting agent is preferable. Used for. Moreover, also when using said other cationically polymerizable compound, a cationic polymerization initiator and / or a thermosetting agent are used suitably.
Examples of the cationic polymerization initiator include a thermal cationic polymerization initiator that generates a protonic acid or a Lewis acid by heating, and a photocationic polymerization initiator that generates a protonic acid or a Lewis acid by light irradiation. Among these, since the electrostatic coating property can be improved, it is preferable to contain a photocationic polymerization initiator and / or a thermal cationic polymerization initiator as the polymerization initiator, and an organic thin film element by light irradiation at the time of curing. It is preferable to contain a thermal cationic polymerization initiator from the viewpoint of preventing the deterioration.

The thermal cationic polymerization initiator may be an ionic thermal cationic polymerization initiator or a nonionic thermal cationic polymerization initiator. From the viewpoint of antistatic properties of the coating film, Cationic polymerization initiators are preferred.
Examples of the thermal cationic polymerization initiator include sulfonium salts, phosphonium salts, quaternary ammonium salts, diazonium salts, iodonium salts, and the like. Of these, sulfonium salts are preferred.
Examples of the counter anion in the thermal cationic polymerization initiator include AsF ₆ ⁻ , SbF ₆ ⁻ , PF ₆ ⁻ , B (C ₆ F ₅ ) ^{4− and the} like.
Examples of the sulfonium salts include triphenylsulfonium boron tetrafluoride, triphenylsulfonium hexafluoride antimony, triphenylsulfonium hexafluoride arsenic, tri (4-methoxyphenyl) sulfonium hexafluoride arsenic, diphenyl (4-phenylthiophenyl). ) Sulfonium arsenic hexafluoride and the like.
Examples of the phosphonium salt include ethyltriphenylphosphonium antimony hexafluoride and tetrabutylphosphonium antimony hexafluoride.
Examples of the quaternary ammonium salt include N, N-dimethyl-N-benzylanilinium antimony hexafluoride, N, N-dimethyl-N- (4-methoxybenzyl) anilinium hexafluoride antimony, N, N -Diethyl-N-benzylanilinium tetrafluoride, N, N-dimethyl-N-benzylpyridinium hexafluoroantimony, N, N-diethyl-N-benzylpyridinium trifluoromethanesulfonic acid, N, N-dimethyl-N -(4-methoxybenzyl) pyridinium hexafluoride antimony, N, N-diethyl-N- (4-methoxybenzyl) pyridinium hexafluoride antimony, N, N-diethyl-N- (4-methoxybenzyl) toluidinium hexafluoride Antimony, N, N-dimethyl-N- (4-methoxybenzyl) toluidini Beam antimony hexafluoride, and the like.
These thermal cationic polymerization initiators may be used alone or in combination of two or more.

Examples of commercially available thermal cationic polymerization initiators include, for example, Adeka Opton CP-66, Adeka Opton CP-77 (both manufactured by ADEKA), and thermal cations having not only thermal activity but also photoactivity. Polymerization initiators, Sun-Aid SI-60, Sun-Aid SI-80, Sun-Aid SI-100, Sun-Aid SI-110, Sun-Aid SI-180 (all manufactured by Sanshin Chemical Industry Co., Ltd.), CXC-1612 (manufactured by King Industries) Etc.

The photocationic polymerization initiator may be an ionic photocationic polymerization initiator or a nonionic photocationic polymerization initiator, but from the viewpoint of antistatic properties of the coating film, ionic light Cationic polymerization initiators are preferred.
Examples of the ionic photocationic polymerization initiator include iodonium salts and sulfonium salts.
Examples of the iodonium salt include (tolylcumyl) iodonium tetrakis (pentafluorophenyl) borate.
Examples of the sulfonium salt include diphenyl-4-thiophenylsulfonium-hexafluoroantimonate.
Examples of the nonionic photocationic polymerization initiator include nitrobenzyl ester, sulfonic acid derivative, phosphate ester, phenol sulfonate ester, diazonaphthoquinone, N-hydroxyimide sulfonate and the like.
Of these photocationic polymerization initiators, diphenyl-4-thiophenylsulfonium-hexafluoroantimonate is preferred.
These cationic photopolymerization initiators may be used alone or in combination of two or more.

As what is marketed among the said photocationic polymerization initiators, RP2074 (made by Rhodia), Adeka optomer SP-170 (made by ADEKA) etc. are mentioned, for example.

As described above, when the (meth) acrylic compound is used as the curable compound according to the present invention or when the polythiol compound and the polyene compound are used in combination, the polymerization initiator is a radical polymerization initiator. Are preferably used.
Examples of the radical polymerization initiator include a photo radical polymerization initiator that generates radicals by light irradiation and a thermal radical polymerization initiator that generates radicals by heating.

As the photo radical polymerization initiator, for example, a benzophenone compound, an acetophenone compound, an acylphosphine oxide compound, a titanocene compound, an oxime ester compound, a benzoin ether compound, thioxanthone, and the like can be preferably used.

Examples of commercially available photo radical polymerization initiators include IRGACURE 184, IRGACURE 369, IRGACURE 379, IRGACURE 651, IRGACURE 819, IRGACURE 907, IRGACURE 2959, IRGACUREOXE01, and Lucin TPO (all manufactured by BASF Methyl Corp. Examples include benzoin ethyl ether and benzoin isopropyl ether (both manufactured by Tokyo Chemical Industry Co., Ltd.). These radical photopolymerization initiators may be used alone or in combination of two or more.

The photo radical polymerization initiator preferably has an absorption wavelength in the visible light region.
Examples of the radical photopolymerization initiator having an absorption wavelength in the visible light region include bis- (2,6-dichlorobenzoyl) phenylphosphine oxide and bis- (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine. Oxide, bis- (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, Acylphosphine oxides such as bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 1- (4- (phenylthio) phenyl) -1,2-octanedione 2- (O-benzoyloxime), O— Acetyl-1- (6- (2-methyl Nzoyl) -9-ethyl-9H-carbazol-3-yl) ethanone oxime and other oxime ester compounds, bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- And titanocene compounds such as (1H-pyrrol-1-yl) -phenyl) titanium.
Examples of the radical photopolymerization initiator having an absorption wavelength in the visible light region include IRGACURE819, Lucyrin TPO, IRGACUREOXE01, IRGACUREOXE02, IRGACURE784 (all manufactured by BASF Japan).

Examples of the thermal radical polymerization initiator include peroxides and azo compounds. Examples of commercially available products include perbutyl O, perhexyl O, perbutyl PV (all manufactured by NOF Corporation), V-30, V-65, V-501, V-601, VPE-0201 (all manufactured by Wako Pure Chemical Industries, Ltd.) and the like. These thermal radical polymerization initiators may be used alone or in combination of two or more.

The content of the polymerization initiator is preferably 0.1 parts by weight and preferably 10 parts by weight with respect to 100 parts by weight of the entire curable resin composition for electrostatic coating. When the content of the polymerization initiator is less than 0.1 parts by weight, the curing reaction of the resulting curable resin composition for electrostatic coating may not be allowed to proceed sufficiently. When content of the said polymerization initiator exceeds 10 weight part, the curable resin composition for electrostatic coating obtained may be colored, or it may become inferior to storage stability. The minimum with more preferable content of the said polymerization initiator is 0.2 weight part, and a more preferable upper limit is 5 weight part.

Examples of the thermosetting agent include organic acid hydrazides, imidazole derivatives, amine compounds, polyhydric phenol compounds, acid anhydrides, and the like. Among these, solid organic acid hydrazide is preferably used.

Examples of the solid organic acid hydrazide include 1,3-bis (hydrazinocarbonoethyl) -5-isopropylhydantoin, sebacic acid dihydrazide, isophthalic acid dihydrazide, adipic acid dihydrazide, malonic acid dihydrazide, and the like. Examples of those that can be used include SDH (manufactured by Nippon Finechem Co., Ltd.), ADH (manufactured by Otsuka Chemical Co., Ltd.), Amicure VDH, Amicure VDH-J, Amicure UDH (all manufactured by Ajinomoto Fine Techno Co., Ltd.), and the like.

The content of the thermosetting agent is preferably 0.1 parts by weight with respect to 100 parts by weight of the entire curable resin composition for electrostatic coating, and 40 parts by weight with respect to the preferable upper limit. When content of the said thermosetting agent is less than 0.1 weight part, it may become impossible to fully advance hardening reaction of the curable resin composition for electrostatic coating obtained. When content of the said thermosetting agent exceeds 40 weight part, electrostatic coating efficiency may fall or it may become inferior to storage stability. The minimum with more preferable content of the said thermosetting agent is 0.5 weight part, and a more preferable upper limit is 20 weight part.

When a coating film is formed by the electrostatic coating method, a device such as an organic EL display element may be destroyed or abnormal operation may occur due to charging of the formed coating film. Therefore, it is preferable that the curable resin composition for electrostatic coating of the present invention contains an electrolyte and / or a conductive substance. By containing the electrolyte and / or the conductive substance, the volume resistivity is reduced, and as a result, adverse effects on the device due to charging when the film is thinned by an electrostatic coating method can be suppressed.

The electrolyte is composed of a cation component and an anion component.

The cation component is not particularly limited as long as it is positively charged. For example, tetraalkylphosphonium cation, imidazolium ion, piperidinium ion, pyrrolidinium ion, pyrazonium ion, guanidinium ion, pyridinium ion, sulfonium ion. And metal ions.

As said metal ion, lithium ion, sodium ion, potassium ion etc. are mentioned, Lithium ion and sodium ion are preferable and lithium ion is more preferable.

The anion component is not particularly limited as long as it is negatively charged. For example, halide anions such as fluoride ions, chloride ions, bromide ions, iodide ions, and alkyl sulfates such as methanesulfonate ions. Fluorine-containing compounds such as anion, trifluoromethanesulfonate ion, hexafluorophosphonate ion, trifluorotris (pentafluoroethyl) phosphonate ion, bis (trifluoromethanesulfonyl) imide ion, trifluoroacetate ion, tetrafluoroborate ion Anions, phenol anions such as phenol ions, 2-methoxyphenol ions, 2,6-di-tert-butylphenol ions, acidic amino acid ions such as aspartate ions and glutamate ions, glycine ON, alanine ion, neutral amino acid ion such as phenylalanine ion, N-acylamino acid ion such as N-benzoylalanine ion, N-acetylphenylalanine ion, N-acetylglycine ion, formate ion, acetate ion, decanoic acid ion Carboxylic acid anions such as lactate ions, tartrate ions, hippurate ions, benzoate ions, perchlorate ions, thiocyanate ions, and the like.

Specific examples of the electrolyte include lithium chloride (LiCl), lithium iodide (LiI), lithium perchlorate (LiClO ₄ ), lithium thiocyanate (LiSCN), lithium tetrafluoroborate (LiBF ₄ ), Lithium hexafluoroarsenate (V) (LiAsF ₆ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium hexafluorophosphate (LiPF ₆ ), sodium iodide (NaI), sodium perchlorate (NaClO ₄ ) Sodium thiocyanate (NaSCN), sodium bromide (NaBr), potassium iodide (KI), potassium perchlorate (KClO ₄ ), potassium thiocyanate (KSCN), cesium thiocyanate (CsSCN), silver nitrate (AgNO ₃ ) , Magnesium perchlorate Beam _{(Mg (ClO 4) 2)} , tetraethylammonium perchlorate as tetraalkylammonium compounds, tetrabutyl ammonium perchlorate, borofluoride tetraethylammonium borofluoride tetrabutylammonium, tetrabutylammonium halide, tetrabutylphosphonium acetate and the like Can be mentioned.
Examples of the electrolyte include ionic thermal cationic polymerization initiators such as sulfonium salts, phosphonium salts, quaternary ammonium salts, diazonium salts, and iodonium salts described above, and ionic photocationic polymerization initiators. However, when adjusting the volume resistivity to the above range only by blending these ionic thermal cationic polymerization initiators and ionic photocationic polymerization initiators, ionic thermal cationic polymerization initiators and ionic photocationic polymerizations It is necessary to add a large amount of initiator, and as a result, problems such as coloring, outgassing, and deterioration in storage stability may occur. Therefore, it is preferable to use a combination of the above-described electrolyte or a conductive material described later, and these ionic thermal cationic polymerization initiators and ionic photocationic polymerization initiators.
Further, as the electrolyte, a polymer electrolyte (polymer electrolyte) is also preferably used.
Examples of the polymer electrolyte include polymers such as polystyrene, polyethylene oxide, polypropylene oxide, polyvinylidene fluoride (PVDF) and hexafluoropropylene, PVDF-HFP, porous PVDF, sulfonate, lithium Examples thereof include electrolytes coordinated with a salt, sodium salt, iodonium salt, tetraalkylammonium salt and the like.
One of these electrolytes may be used alone, or two or more thereof may be used in combination.

Examples of the conductive substance include conductive polymers, metal colloids, metal oxide particles, fullerenes, and the like.

Examples of the conductive polymer include polyacetylene, polythiophene, poly (3-alkyl) thiophene, polypyrrole, polyisothiaphthalene, polyethylenedioxythiophene, polyparaphenylene vinylene, poly (2,5-dialkoxy) paraphenylene vinylene. , Polyparaphenylene, polyheptadiyne, poly (3-hexyl) thiophene, polyaniline, and a mixture of two or more thereof.
The number average molecular weight of the conductive polymer is preferably 1000 to 30,000.

Examples of the metal colloid include gold colloid, silver colloid, platinum colloid, and silver chloride colloid.

Examples of the metal oxide particles include titanium dioxide, antimony tin oxide, indium tin oxide, and zirconium dioxide.

Examples of the fullerene include C60 fullerene and C70 fullerene.

The content of the electrolyte and / or the conductive substance is such that the volume resistivity at 25 ° C. of the resulting curable resin composition for electrostatic coating is 10 ¹⁰ Ωcm or less, and the viscosity range described below is used. An amount that can be maintained is preferred.
Specifically, the content of the electrolyte and / or the conductive material is preferably 0.1 parts by weight and 100 parts by weight with respect to 100 parts by weight of the curable compound. If the content of the conductive material is less than 0.1 parts by weight, it may be difficult to sufficiently reduce the volume resistivity of the resulting composition at 25 ° C. When the content of the electrolyte and / or the conductive material exceeds 100 parts by weight, the resulting composition has too high a viscosity, which makes it difficult to use for electrostatic coating, or the resulting curing for electrostatic coating. The curability of the curable resin composition may deteriorate. The more preferable lower limit of the content of the electrolyte and / or the conductive substance is 1 part by weight, and the more preferable upper limit is 50 parts by weight.
“Content of electrolyte and / or conductive substance” means the total content when both the electrolyte and the conductive substance are used, and one of the two is used when only one of them is used. Means content.

The curable resin composition for electrostatic coating of the present invention may contain a photosensitizer. The photosensitizer serves to further improve the polymerization initiation efficiency of the photocationic polymerization initiator or the photoradical polymerization initiator and further accelerate the curing reaction of the curable resin composition for electrostatic coating of the present invention. Have Further, by using a photosensitizer that exhibits a sensitizing effect in the visible light region, the curable resin composition for electrostatic coating of the present invention can be cured by irradiation with visible light.

Examples of the photosensitizer include thioxanthone compounds such as 2,4-diethylthioxanthone, anthracene compounds such as dibutylanthracene and dipropylanthracene, 2,2-dimethoxy-1,2-diphenylethane-1- ON, benzophenone, 2,4-dichlorobenzophenone, methyl o-benzoylbenzoate, 4,4′-bis (dimethylamino) benzophenone, 4-benzoyl-4′methyldiphenyl sulfide, and the like. These photosensitizers may be used independently and 2 or more types may be used in combination.

The content of the photosensitizer is 100 parts by weight of the entire curable resin composition for electrostatic coating, from the viewpoint of the sensitization effect and light transmittance to the deep part of the curable resin composition for electrostatic coating. On the other hand, a preferable lower limit is 0.01 part by weight and a preferable upper limit is 5 parts by weight. The minimum with more preferable content of the said photosensitizer is 0.1 weight part, and a more preferable upper limit is 1 weight part.

The curable resin composition for electrostatic coating of the present invention may contain a polymerization inhibitor.
Examples of the polymerization inhibitor include N-nitrosoarylhydroxylamine salts, phenol derivatives, hydroquinone derivatives, and the like.
Examples of the N-nitrosoarylhydroxylamine salt include ammonium salt, sodium salt, potassium salt, magnesium salt, strontium salt, aluminum salt, copper salt, zinc salt, cerium salt and iron salt of N-nitrosophenyl hydroxylamine. , Nickel salt, cobalt salt and the like. Of these, an ammonium salt of N-nitrosophenyl hydroxylamine is preferable.
Examples of the phenol derivative include p-methoxyphenol, 2,6-di-t-butyl-4-methylphenol, 2,2-methylene-bis (4-methyl-6-t-butylphenol) and the like. . Of these, 2,2-methylene-bis (4-methyl-6-tert-butylphenol) is preferable.
Examples of the hydroquinone derivative include hydroquinone and hydroquinone monomethyl ether. In particular, even if added in a large amount to the curable resin composition for electrostatic coating, it is difficult to volatilize during electrostatic coating, and it is difficult to transfer to a coating film. Salts are preferred.
These polymerization inhibitors may be used alone or in combination of two or more.

The content of the polymerization inhibitor has a preferable lower limit of 0.01 with respect to 100 parts by weight of the entire curable resin composition for electrostatic coating, from the viewpoint of curability of the resulting curable resin composition for electrostatic coating. Part by weight, the preferred upper limit is 2 parts by weight. The minimum with more preferable content of the said polymerization inhibitor is 0.02 weight part, and a more preferable upper limit is 0.5 weight part.

The curable resin composition for electrostatic coating of the present invention may contain an adhesion promoter.
Examples of the adhesion-imparting agent include silane coupling agents such as glycidoxytrimethoxysilane, glycidoxypropylmethyldiethoxysilane, N- (aminoethyl) aminopropyltrimethoxysilane, mercaptopropyltrimethoxysilane, Examples include titanium coupling agents and aluminum coupling agents. These adhesiveness imparting agents may be used alone or in combination of two or more.

The curable resin composition for electrostatic coating according to the present invention further includes an antioxidant, a filler, a curing accelerator, a plasticizer, a surfactant, a heat stabilizer, Additives such as flame retardants, antistatic agents, antifoaming agents, leveling agents, ultraviolet absorbers, organic solvents, etc. may be included as necessary, but from the viewpoint of suppressing outgassing, no organic solvents are included. It is preferable.

Examples of the method for preparing the curable resin composition for electrostatic coating of the present invention include a curable compound, a polymerization initiator and / or a thermosetting agent according to the present invention, and photosensitization added as necessary. Various additives such as agents can be used at room temperature by using known kneaders such as planetary stirrers, homodispers, universal mixers, Banbury mixers, kneaders, two rolls, three rolls, and extruders, either alone or in combination. Or the method etc. which knead | mix uniformly under conditions, such as under normal pressure, pressure reduction, pressurization, or inert gas stream, etc. under heating are mentioned.

The curable resin composition for electrostatic coating of the present invention preferably has a volume resistivity at 25 ° C. of 10 ¹⁰ Ωcm or less. When the volume resistivity is 10 ¹⁰ Ωcm or less, it is possible to suppress adverse effects on the device due to charging when the film is thinned by an electrostatic coating method. A more preferable upper limit of the volume resistivity is 10 ⁸ Ωcm, and a more preferable upper limit is 10 ⁷ Ωcm.
The lower limit of the volume resistivity is not particularly limited, but the substantial lower limit is 10 Ωcm.
The “volume resistivity” can be measured by inserting an electrode into a curable resin composition for electrostatic application at 25 ° C. and flowing an electric current using a resistance meter.
In addition, examples of the method for setting the volume resistivity at 25 ° C. of the curable resin composition for electrostatic coating of the present invention to 10 ¹⁰ Ωcm or less include a method of blending the above-described electrolyte and / or conductive material. It is done.

In the curable resin composition for electrostatic coating of the present invention, the preferred upper limit of the viscosity measured at 25 ° C. and 2.5 rpm using an E-type viscometer is 500 mPa · s. When the viscosity exceeds 500 mPa · s, it may be necessary to heat at a high temperature in order to electrostatically apply the resulting curable resin composition for electrostatic application. A more preferable upper limit of the viscosity of the curable resin composition for electrostatic coating of the present invention is 450 mPa · s, and a further preferable upper limit is 200 mPa · s.
Further, the curable resin composition for electrostatic coating of the present invention preferably has a low viscosity, but the substantial lower limit is 15 mPa · s.

A resin protective film obtained by curing the curable resin composition for electrostatic coating of the present invention is also one aspect of the present invention. The resin protective film of the present invention can be obtained by photocuring and / or thermosetting the curable resin composition for electrostatic coating of the present invention.

Examples of the method for photocuring the curable resin composition for electrostatic coating of the present invention include a method of irradiating light with a wavelength of 300 nm to 400 nm and an integrated light amount of 300 to 3000 mJ / cm ² .

Examples of the light source for irradiating the curable resin composition for electrostatic coating of the present invention with light include a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, an excimer laser, a chemical lamp, a black light lamp, and a micro lamp. Examples include a wave excitation mercury lamp, a metal halide lamp, a sodium lamp, a halogen lamp, a xenon lamp, an LED lamp, a fluorescent lamp, sunlight, and an electron beam irradiation device. These light sources may be used independently and 2 or more types may be used in combination.
These light sources are appropriately selected according to the absorption wavelength of the photocationic polymerization initiator or the photoradical polymerization initiator.

Examples of light irradiation means for the curable resin composition for electrostatic coating of the present invention include simultaneous irradiation of various light sources, sequential irradiation with a time difference, combined irradiation of simultaneous irradiation and sequential irradiation, and the like. Any irradiation means may be used.

Examples of the method for thermosetting the curable resin composition for electrostatic coating of the present invention include a method of heating at 80 to 150 ° C.

An electronic device obtained by protecting an organic thin film element with the resin protective film of the present invention is also one aspect of the present invention. The organic thin film element is protected by the resin protective film of the present invention obtained by electrostatically applying and curing the curable resin composition for electrostatic coating of the present invention, thereby preventing moisture from entering the organic thin film element. Thus, the performance and durability of the organic thin film element can be maintained high, and the electronic device can be made thinner.
Also, a step of applying the curable resin composition for electrostatic coating of the present invention on the organic thin film element by an electrostatic coating method, and curing the applied curable resin composition for electrostatic coating on the organic thin film element An electronic device manufacturing method including a step of forming a resin protective film on the substrate is also one aspect of the present invention.

As said organic thin film element, an organic electroluminescent element (henceforth "organic EL element"), an organic thin film solar cell element, etc. are mentioned, for example.
The organic EL element is formed, for example, by vacuum-depositing a hole injection electrode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and an electron injection electrode in order on a substrate. can do.

When the organic thin film element is an organic EL element, the electronic device may have a bottom emission structure in which light is extracted from the lower surface side (side where the element is not formed on the substrate), or the upper surface side (element is formed on the substrate). A top emission structure in which light is extracted from the other side.

The organic thin film element is placed on a substrate and protected by the resin protective film of the present invention obtained by electrostatic coating and curing of the curable resin composition for electrostatic coating of the present invention. It is preferable to cover the region including the element with an inorganic material film in advance.
As the substrate, for example, a transparent glass substrate can be used in a simple matrix type (passive type) optical device, and in an active matrix type optical device, a plurality of TFTs (thin film transistors) and planarization are provided on the transparent glass substrate. A TFT substrate with a layer can be used.

Examples of the inorganic material constituting the inorganic material film include silicon nitride (SiN _x ), silicon oxide (SiO _x ), and aluminum oxide (Al ₂ O ₃ ). The inorganic material film may be a single layer or may be a laminate of a plurality of types of layers.

Examples of a method of covering the organic thin film element with the inorganic material film include a sputtering method and an electron cyclotron resonance (ECR) plasma CVD method when the inorganic material film is made of silicon nitride or silicon oxide.
The sputtering method is preferably carried out under conditions of room temperature, power of 50 to 1000 W, and pressure of 0.001 to 0.1 Torr using, for example, argon gas or nitrogen gas alone or as a mixed gas as a carrier gas.
The ECR plasma CVD method uses, for example, a mixed gas of SiH ₄ and O ₂ (in the case of silicon oxide) or a mixed gas of SiH ₄ and N ₂ (in the case of silicon nitride), at a temperature of 30 ° C. to 100 ° C., It is preferable to carry out under the conditions of a pressure of 10 mTorr to 1 Torr, a frequency of 2.45 GHz, and a power of 10 to 1000 W.

The process of apply | coating the curable resin composition for electrostatic coating of this invention on the said organic thin film element by an electrostatic coating method can be performed at about 10-40 degreeC low temperature.

The step of applying the curable resin composition for electrostatic coating of the present invention on the organic thin film element by an electrostatic coating method can be performed under atmospheric pressure or a reduced pressure atmosphere, but can be performed under atmospheric pressure. preferable. Moreover, when the said (meth) acrylic compound is used as a curable compound concerning this invention, it is preferable to carry out in nitrogen atmosphere.

In the step of curing the applied curable resin composition for electrostatic application to form a resin protective film on the organic thin film element, the curable resin composition for electrostatic application of the present invention is light-transmitted by the above-described method. It can be formed as a resin protective film of the present invention by curing and / or thermosetting.

Although the thickness of the resin protective film formed in the electronic device of the present invention is not particularly limited, from the viewpoint of preventing the pressure on the organic thin film element and the electrode due to the internal stress of the inorganic material film, and the thinning of the electronic device The preferred lower limit is 0.1 μm and the preferred upper limit is 20 μm. The more preferable lower limit of the thickness of the resin protective film is 0.3 μm, and the more preferable upper limit is 2 μm.

In the electronic device of the present invention, an inorganic material film is preferably further laminated on the resin protective film in order to enhance the effect of protecting the organic thin film element from moisture and oxygen in the atmosphere. The inorganic material constituting the inorganic material film laminated on the resin protective film and the forming method are the same as the inorganic material film covering the organic thin film element described above.

Although the thickness of the inorganic material film formed on the resin protective film is not particularly limited, the preferable lower limit is 0.05 μm, preferably from the viewpoint of preventing moisture intrusion, preventing cracking of the inorganic material film, and forming time. The upper limit is 20 μm. The more preferable lower limit of the thickness of the inorganic material film formed on the resin protective film is 0.1 μm, and the more preferable upper limit is 10 μm.

In order to more strictly protect the electronic device of the present invention from light and oxygen, two or more resin protective films and inorganic material films may be alternately laminated. The materials and forming methods of the resin protective film and the inorganic material film that are alternately stacked are the same as those of the resin protective film and the inorganic material film described above.

ADVANTAGE OF THE INVENTION According to this invention, the uniform thin film can be formed efficiently under atmospheric pressure, and the curable resin composition for electrostatic coating which can suppress generation | occurrence | production of outgas can be provided. Moreover, according to this invention, the manufacturing method of the resin protective film which uses this curable resin composition for electrostatic coating, an electronic device, and an electronic device can be provided.

FIG. 1 is a schematic view showing an example of a process for producing a thin film by an electrostatic coating method.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Example 1
As a curable compound according to the present invention, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane (manufactured by Toagosei Co., Ltd., “Aron oxetane OXT-212”, boiling point 270 ° C., molecular weight 228) 50 parts by weight, and , 50 parts by weight of di (1-ethyl (3-oxetanyl)) methyl ether (manufactured by Toagosei Co., Ltd., “Aron oxetane OXT-221”, boiling point 270 ° C., molecular weight 214), and diphenyl-4-as a photocationic polymerization initiator 1.0 part by weight of thiophenylsulfonium hexafluoroantimonate (manufactured by ADEKA, “Adekaoptomer SP-170”) and 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd., “DETX- S ") 0.2 part by weight of a homodisper type stirring mixer (manufactured by Primics," Homodisper L type ") There, it was mixed under stirring at a stirring speed 3000 rpm, to obtain an electrostatic coating curable resin composition.
About the obtained curable resin composition for electrostatic coating, the volume resistivity measured at 25 ° C. using a resistance meter (manufactured by Kawaguchi Denki Seisakusho, “Multimeter MMA II-17D”, electrode LP-05) is It was 5 × 10 ⁹ Ωcm.

(Examples 2 to 20, Comparative Examples 1 and 2)
A curable resin composition for electrostatic coating was produced in the same manner as in Example 1 except that the materials and the amounts used were those shown in Tables 1 to 3.
Tables 1 to 3 show the volume resistivity measured in the same manner as in Example 1 for each of the curable resin compositions for electrostatic coating obtained in Examples 2 to 20 and Comparative Examples 1 and 2.

<Evaluation>
The following evaluation was performed about each curable resin composition for electrostatic coating obtained by the Example and the comparative example. The results are shown in Tables 1-3.

(Applicability and film flatness)
Each curable resin composition for electrostatic coating obtained in Examples and Comparative Examples was filled into a 1 mL microsyringe. A stainless syringe needle was attached to the microsyringe and installed in a syringe pump. A high voltage power source anode was connected to the tip of the injection needle. A cathode was connected to a metal plate on which the substrate was placed, and an alkali-free glass plate (Asahi Glass Co., Ltd., 10 cm square, 0.7 mm thickness) serving as the substrate was placed on the metal plate. The coating conditions were such that the distance from the tip of the injection needle to the substrate was 5 cm, the applied voltage was 10 kV, the composition supply from the syringe pump was 30 μL / min, and the coating was performed for 1 minute to form a 1 μm film. . The coated film was irradiated with visible light of 405 nm with an LED lamp to cure the coating film.
The applicability was evaluated as “◯” when uniform spray application was possible, and “X” when uniform spray application was not possible.
In addition, when the film is cured and visually observed, there is no turbidity or unevenness, “◯”, and when there is slight turbidity or unevenness, “△”, white turbidity or unevenness occurs. The flatness of the film was evaluated as “x”.

(Film thickness)
The film | membrane applied above was partially shaved and the sample for film thickness measurement was produced by providing a level | step difference. About the obtained sample for film thickness measurement, the film thickness was measured using the surface roughness meter (the product made by KLA Tencor, "Alpha-Step IQ").

(Antistatic property)
About the coating film obtained by carrying out similarly to said "(application | coating property and film flatness)", the earth wire was touched immediately after application | coating, and the surface potential after 10 second was measured. The surface potential was measured with a static electricity meter ("FMX-004" manufactured by Simco Japan). When the surface potential is less than 0.5 kV, “◎”, when it is 0.5 kV or more and less than 1 kV, “◯”, when it is 1 kV or more and less than 5 kV, “△”, when it is 5 kV or more Was evaluated as antistatic property.

(Performance of electronic devices)
(1) Fabrication of a substrate on which an organic EL element is disposed A glass substrate (length 25 mm, width 25 mm, thickness 0.7 mm) on which an ITO electrode is formed to a thickness of 1000 mm is used as a substrate. The substrate was ultrasonically washed with acetone, an aqueous alkali solution, ion-exchanged water, and isopropyl alcohol for 15 minutes each, then washed with boiled isopropyl alcohol for 10 minutes, and further UV-ozone cleaner (manufactured by Nippon Laser Electronics Co., Ltd., The last treatment was performed with “NL-UV253”).
Next, this substrate is fixed to the substrate folder of the vacuum deposition apparatus, and 200 mg of N, N′-di (1-naphthyl) -N, N′-diphenylbenzidine (α-NPD) is put into an unglazed crucible in other different ways. 200 mg of tris (8-hydroxyquinola) aluminum (Alq ₃ ) was put in an unglazed crucible, and the pressure in the vacuum chamber was reduced to 1 × 10 ⁻⁴ Pa. Thereafter, the crucible containing α-NPD was heated and α-NPD was deposited on the substrate at a deposition rate of 15 Å / s to form a 600 正 孔 hole transport layer. Next, the crucible containing Alq ₃ was heated to form a light emitting layer having a thickness of 600 Å at a deposition rate of 15 Å / s. Thereafter, the substrate on which the hole transport layer and the light emitting layer are formed is transferred to another vacuum vapor deposition apparatus, and 200 mg of lithium fluoride is added to the tungsten resistance heating boat in the vacuum vapor deposition apparatus, and the aluminum wire 1 is applied to another tungsten boat. 0.0 g was added. Then, after reducing the pressure in the vapor deposition unit of the vacuum vapor deposition apparatus to 2 × 10 ⁻⁴ Pa and depositing 5 μm of lithium fluoride at a deposition rate of 0.2 kg / s, deposit 1000 μm of aluminum at a rate of 20 kg / s. did. The inside of the vapor deposition unit was returned to normal pressure with nitrogen, and the substrate on which the 10 mm × 10 mm organic EL elements were arranged was taken out.

(2) Coating with inorganic material film A A mask having an opening of 13 mm × 13 mm is installed on the substrate on which the obtained organic EL element is arranged so as to cover the entire organic EL element, and plasma CVD is used. Thus, an inorganic material film A was formed.
The inorganic material film A uses SiH ₄ gas and nitrogen gas as source gases, the flow rates are 10 sccm and 200 sccm, the RF power is 10 W (frequency: 2.45 GHz), the chamber temperature is 100 ° C., and the chamber pressure is 0. The film was formed under the condition of 9 Torr.
The formed inorganic material film A had a thickness of about 1 μm.

(3) Formation of Resin Protective Film Each curable resin composition for electrostatic coating obtained in Examples and Comparative Examples was filled into a 1 mL microsyringe. A stainless syringe needle was attached to the microsyringe and installed in a syringe pump. A high voltage power source anode was connected to the tip of the injection needle. A cathode was connected to a metal plate on which the substrate was placed, and an alkali-free glass plate (Asahi Glass Co., Ltd., 10 cm square, 0.7 mm thickness) serving as the substrate was placed on the metal plate. The coating conditions were such that the distance from the tip of the injection needle to the substrate was 5 cm, the applied voltage was 10 kV, the composition supply from the syringe pump was 30 μL / min, and the coating was performed for 1 minute to form a 1 μm film. . The applied film was irradiated with visible light of 405 nm with an LED lamp, the coating film was cured, and a resin protective film was formed. When the curable resin composition for electrostatic coating obtained in Examples 8, 14, and 16 was used, instead of irradiating 405 nm visible light, it was irradiated with 365 nm ultraviolet light with an LED lamp. The film was cured. When the curable resin composition for electrostatic coating obtained in Examples 9, 10 and 17 was used, the coating film was cured by heating at 100 ° C. for 60 minutes instead of irradiating visible light of 405 nm. Went.

(4) A mask having an opening of 12 mm × 12 mm is installed so as to cover the entire 11 mm × 11 mm resin protective film of the substrate on which the organic EL element on which the coating resin protective film is formed by the inorganic material film B is disposed. And the inorganic material film | membrane B was formed by plasma CVD method, and the electronic device (organic EL element device) was obtained.
The inorganic material film B uses SiH ₄ gas and nitrogen gas as source gases, the flow rates of each are SiH ₄ gas 10 sccm, nitrogen gas 200 sccm, RF power is 10 W (frequency 2.45 GHz), chamber temperature is 100 ° C., It formed on the conditions which set the pressure in a chamber to 0.9 Torr.
The formed inorganic material film B had a thickness of about 1 μm.

(5) Luminous state of the electronic device The obtained electronic device was exposed for 24 hours under conditions of 25 ° C. and 50% RH, respectively, and then a voltage of 6 V was applied to illuminate the electronic device (light emitting and dark spots, pixels). The presence or absence of peripheral quenching was visually observed, and a case where no dark spots or peripheral quenching occurred and light was emitted uniformly was evaluated as “◯”, and a case where even a slight dark spot or peripheral quenching was observed was evaluated as “X”. In addition, since the curable resin composition for electrostatic coating obtained in Comparative Examples 1 and 2 could not be applied uniformly, an electronic device could not be produced.

ADVANTAGE OF THE INVENTION According to this invention, the uniform thin film can be formed efficiently under atmospheric pressure, and the curable resin composition for electrostatic coating which can suppress generation | occurrence | production of outgas can be provided. Moreover, according to this invention, the manufacturing method of the resin protective film which uses this curable resin composition for electrostatic coating, an electronic device, and an electronic device can be provided.

1 Nozzle 2 Coating liquid 3 Coating liquid particle 4 Material to be coated

Claims (11)

An organic thin film element encapsulant for electrostatic coating for forming a resin protective film on an organic thin film element by applying it onto an organic thin film element by an electrostatic coating method and then photocuring and / or heat curing. ,
A boiling point of less than 420 ° C. and / or a molecular weight of less than 340 and a liquid curable compound at 25 ° C., a polymerization initiator and / or a thermosetting agent ,
The curable compound having a boiling point of less than 420 ° C. and / or a molecular weight of less than 340 and liquid at 25 ° C. is at least one selected from the group consisting of epoxy compounds, oxetanyl compounds, and vinyl ether compounds. An organic thin film element encapsulant for electrostatic coating characterized by the above. From the group consisting of a curable compound that has a boiling point of 420 ° C. or higher, a molecular weight of 340 or higher, and is liquid at 25 ° C., a curable compound that is solid at 25 ° C., and a non-curable compound that is solid at 25 ° C. The organic thin film element sealant for electrostatic coating according to claim 1, comprising at least one selected. The organic thin film element sealant for electrostatic coating according to claim 1 or 2, wherein the main chain contains a curable compound having an alkylene oxide structure. 4. The organic thin film element encapsulant for electrostatic coating according to claim 1, wherein the polymerization initiator contains a photocationic polymerization initiator and / or a thermal cationic polymerization initiator . The organic thin film element sealing agent for electrostatic coating according to claim 4 , comprising a thermal cationic polymerization initiator as the polymerization initiator . The organic thin film element encapsulant for electrostatic coating according to claim 1, comprising an electrolyte and / or a conductive substance. The organic thin film element encapsulant for electrostatic coating according to claim 1 , wherein a volume resistivity at 25 ° C. is 10 ¹⁰ Ωcm or less. A resin protective film obtained by curing the organic thin film element sealant for electrostatic coating according to claim 1, 2, 3, 4, 6, or 7 . An electronic device comprising an organic thin film element protected by the resin protective film according to claim 8 . The electronic device according to claim 9 , wherein an inorganic material film is further laminated on the resin protective film. Applying the organic thin film element sealant for electrostatic coating according to claim 1, 2, 3, 4 or 7 on the organic thin film element by an electrostatic coating method, and curing for applied electrostatic coating And a step of curing a functional resin composition to form a resin protective film on the organic thin film element.

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