KR20200138172A - Electronic device encapsulation body, sheet-like adhesive, adhesive film for electronic device encapsulation, and manufacturing method of electronic device encapsulation body - Google Patents

Abstract

The present invention provides an electronic device and an electronic device encapsulation member having an adhesive cured product layer for sealing between an ultraviolet-impermeable functional film and the electronic device, a sheet-like adhesive used for forming the cured adhesive layer, and the functional film It is an adhesive film for electronic device sealing which has an adhesive layer which consists of a sheet-like adhesive, and a manufacturing method of an electronic device sealing body.

Description

Electronic device encapsulation body, sheet-like adhesive, adhesive film for electronic device encapsulation, and manufacturing method of electronic device encapsulation body

The present invention provides an electronic device encapsulation body comprising an electronic device and a cured adhesive layer for sealing between the functional film and an ultraviolet non-transmissive functional film, a sheet-like adhesive used for forming the cured adhesive layer, and the functional film. It relates to an adhesive film for electronic device sealing having an adhesive layer made of a sheet-like adhesive, and a method of manufacturing an electronic device sealing body.

As a sealing adhesive for sealing electronic devices such as organic EL elements, there is a thermosetting adhesive. However, in the thermosetting adhesive, if the device is cured after sealing, damage to the device by heat is concerned. On the other hand, in the case of curing before bonding to an electronic device, there is a problem that the initial pressure-sensitive adhesive property is lost.

On the other hand, if it is an active energy ray-curable adhesive such as ultraviolet rays, even in the case of curing after bonding to an electronic device, damage to electronic devices such as organic EL elements is small.

In Patent Document 1, an adhesive for sealing electronic devices containing a compound having a cyclic ether group and a photocationic polymerization initiator is described.

Japanese Patent Publication No. 2014-534309 (International Publication No. 2013/057265)

In Patent Document 1, it is described that "a pressure-sensitive adhesive is preferably partially or finally crosslinked first after application to an electronic device" [paragraph (0066)]. In addition, the cation UV curing for crosslinking as described above was based on the premise that the sealing adhesive was carried on a material that transmits ultraviolet rays, such as a PET liner or glass.

The present invention is based on the premise that the member to which the sealing adhesive is bonded is an ultraviolet-impermeable functional film, and an electronic device encapsulant comprising a cured adhesive layer for sealing between the functional film and the electronic device, and the cured adhesive It is an object to provide a sheet-like adhesive as a layer forming material, an adhesive film for sealing electronic devices having an adhesive layer composed of the functional film and the sheet-like adhesive, and a method for producing an electronic device sealing body.

In the adhesive containing the compound having a cyclic ether group and a photocationic polymerization initiator, even after irradiation with ultraviolet rays, the adhesiveness of the adhesive surface remains. Therefore, even after irradiating ultraviolet rays, a sheet-like adhesive made of such an adhesive can be attached to an electronic device. Then, in such a sheet-like adhesive, the adhesive layer is cured over time after irradiation with ultraviolet rays, and finally, the layer structure of (ultraviolet non-transmissive functional film)/(cured adhesive layer)/(electronic device) An electronic device sealing body having excellent durability can be obtained efficiently.

In this way, according to the present invention, the electronic device sealing body of the following [1] to [4], the sheet-like adhesive of [5], the adhesive film for sealing electronic devices of [6] and (7], [8] and [9] ] Is provided.

(1) A functional film having a wavelength of 365 nm and a transmittance of UV rays of 60% or less, an electronic device, and an adhesive cured product layer sealing between the functional film and the electronic device, and the cured adhesive layer comprises the following (A The electronic device sealing body which is a cured product of a sheet-like adhesive containing a component) and a component (B).

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

[2] A sheet-like adhesive comprising the following components (A) and (B), which is used in the production of the electronic device sealing body according to claim 1.

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

[3] The sheet-like adhesive according to [2], wherein the sheet-like adhesive has a release film on at least one surface, and an adhesive force to a soda glass plate measured under the following condition (i) is 3 N/25 mm or more.

(i) On the side opposite to the side to which the release film of the sheet-like adhesive is adhered, a laminate was prepared in which a 23 μm-thick polyethylene terephthalate film was deposited with aluminum, and the release film was bonded to each other. , From the release film side, irradiation with ultraviolet rays having a wavelength of 365 nm, illuminance: 50 mW/cm 2, light quantity: 200 mJ/cm 2, and 3 minutes later, the release film was removed from the laminate After peeling, the exposed layer of the sheet-like adhesive was opposed to the soda glass plate, affixed to the glass by reciprocating a roll of 2 kg on the laminated body, and stored at 23° C. in an environment of 50% relative humidity for 24 hours. ° Perform a peel test.

[4] The sheet-like adhesive according to [2] or [3], further comprising at least one selected from the group consisting of a modified polyolefin resin and a phenoxy resin.

[5] An adhesive film for sealing an electronic device, comprising a functional film having a wavelength of 365 nm and a transmittance of 60% or less of ultraviolet rays, and an adhesive layer comprising a sheet-like adhesive comprising the following components (A) and (B).

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

(6) The adhesive film for electronic device sealing has a release film on the surface of the adhesive layer on the side to which the functional film is not bonded, and the adhesive force to the soda glass plate measured under the following condition (ii) is 3 N/ The adhesive film for sealing an electronic device according to [5], which is 25 mm or more.

(ii) In the state of bonding the release film to the adhesive film for sealing electronic devices, from the release film side, irradiation with ultraviolet rays having a wavelength of 365 nm under conditions of illuminance: 50 mW/cm 2 and light quantity: 200 mJ/cm 2 And 3 minutes later, the release film is peeled from the adhesive adhesive film for electronic device sealing, the exposed adhesive layer is opposed to a soda glass plate, and a 2 kg roll is reciprocated once on the adhesive film for electronic device sealing. After affixing to a soda glass plate and storing for 24 hours in an environment of 50% relative humidity at 23°C, a 180° peeling test is performed.

[7] Further, the adhesive film for sealing an electronic device according to [5] or [6], wherein the sheet-like adhesive contains at least one selected from the group consisting of a modified polyolefin resin and a phenoxy resin.

[8] (α1) a step of irradiating ultraviolet rays from the surface side closer to the adhesive layer than the functional film to the adhesive film for electronic device sealing of any one of the above [5] to [7];

(β1) having a step of attaching the adhesive film to an electronic device,

A method of manufacturing an electronic device encapsulation body in which the step (α1) is performed before the step (β1).

(9) (α2) a step of irradiating ultraviolet rays to a sheet-like adhesive comprising the following components (A) and (B), and

(β2) having a step of affixing the sheet-like adhesive to a functional film or electronic device having a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm,

A method of manufacturing an electronic device encapsulation body in which the step (α2) is performed before the step (β2).

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

According to the present invention, even after irradiation with ultraviolet rays, it strongly adheres to an electronic device that is an ultraviolet-impermeable functional film or adherend, and does not cause peeling at the time of sticking or after sticking, and the adhesive layer is cured over time. Thus, it is possible to finally obtain a device encapsulant having excellent durability.

1 is a diagram showing an example of an electronic device sealing member of the present invention.
2 is a schematic process chart of a method for manufacturing an electronic device encapsulation body of the present invention.
3 is a schematic process chart of a method for manufacturing an electronic device encapsulation body according to the present invention.

Hereinafter, the present invention is categorized into 2) an electronic device encapsulant, 2) a sheet-like adhesive, 3) an adhesive film for encapsulating an electronic device, and 4) a method of manufacturing an electronic device encapsulant, and will be described in detail.

1) Electronic device encapsulant

The electronic device encapsulation body of the present invention includes a functional film having a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm, an electronic device, and a cured adhesive layer sealing between the functional film and the electronic device, and the cured adhesive layer, It is characterized in that it is a cured product of a sheet-like adhesive (hereinafter sometimes referred to as "the sheet-like adhesive of the present invention") containing the following component (A) and component (B).

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

1 shows an example of the layer structure of the electronic device encapsulation body of the present invention. The electronic device sealing body 10 shown in FIG. 1 is laminated so that the electronic device 3 and the cured adhesive layer 2 face each other so as to cover the surface of the electronic device 3, and the transmittance of ultraviolet rays having a wavelength of 365 nm is The functional film 1 which is 60% or less has a layered structure arranged on the outermost surface.

In the electronic device encapsulation body of the present invention, examples of the electronic device as the object to be encapsulated include organic EL elements such as organic EL displays and organic EL lighting; Liquid crystal elements such as liquid crystal displays; Electronic paper; Solar cell elements such as organic thin film solar cells; Light-emitting diodes, etc. are mentioned.

[Functional film]

The functional film 1 constituting the electronic device encapsulation body of the present invention is a film in which the transmittance of ultraviolet rays at a wavelength of 365 nm is 60% or less. The transmittance of ultraviolet rays having a wavelength of 365 nm of the functional film is preferably 55% or less, and more preferably 50% or less from the viewpoint of obtaining more remarkable effects of the present invention.

The transmittance of ultraviolet rays with a wavelength of 365 nm of the functional film can be measured by the method described in Examples.

The functional film 1 used in the present invention has a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm, and is not particularly limited as long as it is a film having any function. For example, a conductive layer, a gas barrier film, an antireflection film, a retardation film, a viewing angle improving film, and a luminance improving film, in which the transmittance of ultraviolet rays having a wavelength of 365 nm is 60% or less can be mentioned. Among these, examples of the gas barrier film include a film having a film of a metal or an inorganic compound, and a film having a film of a metal is preferable. Examples of the metal to be used include aluminum, zinc, and copper, and among them, aluminum is preferable.

The thickness of the functional film used in the present invention is not particularly limited, but is usually 5 to 200 µm, preferably 10 to 100 µm.

In the case of having a functional film having a transmittance of UV rays at a wavelength of 365 nm of 60% or less, after bonding the sheet-like adhesive to the electronic device, even if ultraviolet rays are irradiated from the functional film side, the amount of ultraviolet rays reaching the sheet-like adhesive is small, The sheet-like adhesive cannot be cured.

As described later, the sheet-like adhesive of the present invention is cured by photocationic polymerization. The photocationic polymerization reaction has a relatively slow reaction rate compared to a radical polymerization reaction or the like. Therefore, even after irradiating the sheet-like adhesive with ultraviolet rays, while the curing reaction is in progress, the sheet-like adhesive has sufficient adhesiveness, so it strongly adheres to the electronic device as the adherend, causing peeling during or after affixing. Can be prevented. Moreover, the adhesive layer hardens over time, and finally, the sealing body of an electronic device excellent in durability can be obtained.

〔Adhesive cured product layer〕

The cured adhesive layer 2 of the electronic device encapsulation body of the present invention is made of the cured product of the sheet-like adhesive of the present invention, and serves to seal the electronic device and bond the electronic device and the functional film.

〔Sheet-shaped adhesive〕

The sheet-like adhesive of the present invention is a sheet-like article having adhesiveness, and contains the following components (A) and (B).

(A) Compound having a cyclic ether group

(B) photocationic polymerization initiator

The sheet-like adhesive refers to an adhesive formed into a sheet that exhibits non-flowability at room temperature (about 25°C). In the present invention, the sheet-like adhesive may be in the form of a strip, or may be in the form of a long (band).

(Component (A): Compound having a cyclic ether group)

The sheet-like adhesive of the present invention contains a compound having a cyclic ether group as component (A).

By using a compound having a cyclic ether group, a cured product of a sheet-like adhesive having excellent curability and vapor barrier properties of the sheet-like adhesive can be obtained.

Examples of the cyclic ether group include an oxeane group (epoxy group), an oxetane group (oxetanyl group), a tetrahydrofuryl group, and a tetrahydropyranyl group.

The compound having a cyclic ether group refers to a compound having at least one or more cyclic ether groups in the molecule. Among them, from the viewpoint of obtaining a cured product of an adhesive having more excellent adhesive strength, a compound having an oxysilane group or an oxetane group is preferable, and a compound having two or more oxysilane groups or oxetane groups in the molecule is particularly preferable.

Examples of the compound having an oxysilane group in the molecule include an aliphatic epoxy compound (excluding an alicyclic epoxy compound), an aromatic epoxy compound, and an alicyclic epoxy compound.

Examples of the aliphatic epoxy compound include monofunctional epoxy compounds such as glycidyl ether products of aliphatic alcohols and glycidyl esters of alkyl carboxylic acids;

And polyfunctional epoxy compounds such as polyglycidyl ether products of aliphatic polyhydric alcohols or alkylene oxide adducts thereof, polyglycidyl esters of aliphatic long chain polybasic acids, and epoxy compounds having a triazine skeleton.

Representative compounds of these aliphatic epoxy compounds include allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, C12 to 13 mixed alkyl glycidyl ether, and 1,4-butanediol diglycidyl Ether, neopentyl glycol diglycidyl ether, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, tetraglycidyl ether of sorbitol, hexaglycidyl ether of dipentaerythritol, di of polyethylene glycol To glycidyl ether of polyhydric alcohols such as glycidyl ether, diglycidyl ether of polypropylene glycol, dicyclopentadiene dimethanol diglycidyl ether, and aliphatic polyhydric alcohols such as propylene glycol, trimethylolpropane, and glycerin Polyglycidyl ether product of polyether polyol obtained by adding 1 type or 2 or more types of alkylene oxide, diglycidyl ester of aliphatic long chain dibasic acid;

Monoglycidyl ether of aliphatic higher alcohol and glycidyl ester of higher fatty acid, epoxidized soybean oil, octyl epoxy stearate, butyl epoxy stearate, epoxidized polybutadiene;

2,4,6-tri(glycidyloxy)-1,3,5-triazine, etc. are mentioned.

Moreover, as an aliphatic epoxy compound, a commercial item can also be used. Commercially available products include Denacol EX-121, Denacol EX-171, Denacol EX-192, Denacol EX-211, Denacol EX-212, Denacol EX-313, Denacol EX-314, Denacol EX- 321, Denacol EX-411, Denacol EX-421, Denacol EX-512, Denacol EX-521, Denacol EX-611, Denacol EX-612, Denacol EX-614, Denacol EX-622, Denacol EX-810, Denacol EX-811, Denacol EX-850, Denacol EX-851, Denacol EX-821, Denacol EX-830, Denacol EX-832, Denacol EX-841, Denacol EX-861, Denacol EX-911, Denacol EX-941, Denacol EX-920, Denacol EX-931 (above, manufactured by Nagase Chemtex);

Epolite M-1230, Epolite 40E, Epolite 100E, Epolite 200E, Epolite 400E, Epolite 70P, Epolite 200P, Epolite 400P, Epolite 1500NP, Epolite 1600, Epolite 80MF, Epolite 100MF ( As mentioned above, Kyoeisha Chemical Co., Ltd. make);

Adeca Glycyrol ED-503, Adeca Glycyrol ED-503G, Adeca Glycyrol ED-506, Adeca Glycyrol ED-523T, Adeca Resin EP-4088S, Adeca Resin EP-4088L, Adeka resin EP-4080E (above, manufactured by ADEKA);

TEPIC-FL, TEPIC-PAS, TEPIC-UC (above, manufactured by Nissan Chemical Corporation), etc. are mentioned.

Examples of the aromatic epoxy compound include polyhydric phenols having at least one or more aromatic rings, such as phenol, cresol, and butylphenol, or mono/polyglycidyl ether products of the alkylene oxide adducts thereof.

Representative compounds of these aromatic epoxy compounds include glycidyl ether products or epoxy novolac resins of bisphenol A, bisphenol F, or a compound to which an alkylene oxide is further added;

Mono/polyglycidyl ether products of aromatic compounds having two or more phenolic hydroxyl groups such as resorcinol, hydroquinone, and catechol;

Glycidyl ether products of aromatic compounds having two or more alcoholic hydroxyl groups such as phenyl dimethanol, phenyl diethanol, and phenyl dibutanol;

And glycidyl esters of polybasic acid aromatic compounds having two or more carboxylic acids such as phthalic acid, terephthalic acid and trimellitic acid, glycidyl esters of benzoic acid, epoxidation products of styrene oxide or divinylbenzene, and the like.

Moreover, as an aromatic epoxy compound, a commercial item can also be used. Commercially available products include Denacol EX-146, Denacol EX-147, Denacol EX-201, Denacol EX-203, Denacol EX-711, Denacol EX-721, Oncoat EX-1020, Oncoat EX- 1030, Oncoat EX-1040, Oncoat EX-1050, Oncoat EX-1051, Oncoat EX-1010, Oncoat EX-1011, Oncoat 1012 (above, manufactured by Nagase Chemtex);

Ogsol PG-100, Ogsol EG-200, Ogsol EG-210, Ogsol EG-250 (above, manufactured by Osaka Gas Chemical);

HP4032, HP4032D, HP4700 (above, manufactured by DIC Corporation);

ESN-475V (above, manufactured by Shinnittetsu Corporation);

JER (Guepicoat) YX8800 (made by Mitsubishi Chemical Corporation);

Maproof G-0105SA, Maproof G-0130SP (above, manufactured by Nichiyu Co., Ltd.);

Epiclon N-665, Epiclon HP-7200 (above, manufactured by DIC);

EOCN-1020, EOCN-102S, EOCN-103S, EOCN-104S, XD-1000, NC-3000, EPPN-501H, EPPN-501HY, EPPN-502H, NC-7000L (above, manufactured by Nippon Explosives);

Adeka resin EP-4000, Adeka resin EP-4005, Adeka resin EP-4100, Adeka resin EP-4901 (above, manufactured by ADEKA);

TECHMORE VG-3101L (above, manufactured by Printech Corporation), etc. are mentioned.

As the alicyclic epoxy compound, a polyglycidyl ether product of a polyhydric alcohol having at least one or more alicyclic structures, or a cyclohexene oxide or cyclopentene oxide obtained by epoxidating a cyclohexene or cyclopentene ring-containing compound with an oxidizing agent. Cycloalkene oxide compounds, such as a compound, are mentioned.

Representative compounds of these alicyclic epoxy compounds include hydrogenated bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 3,4-epoxy-1-methyl Cyclohexyl-3,4-epoxy-1-methylhexanecarboxylate, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy -3-Methylcyclohexylmethyl-3,4-epoxy-3-methylcyclohexanecarboxylate, 3,4-epoxy-5-methylcyclohexylmethyl-3,4-epoxy-5-methylcyclohexanecarboxylate , Bis(3,4-epoxycyclohexylmethyl)adipate, 3,4-epoxy-6-methylcyclohexanecarboxylate, methylenebis(3,4-epoxycyclohexane), propane-2,2-diyl- Bis(3,4-epoxycyclohexane), 2,2-bis(3,4-epoxycyclohexyl)propane, dicyclopentadienediepoxide, ethylenebis(3,4-epoxycyclohexanecarboxylate), Dioctyl epoxy hexahydrophthalate, di-2-ethylhexyl epoxy hexahydrophthalate, 1-epoxyethyl-3,4-epoxycyclohexane, 1,2-epoxy-2-epoxyethylcyclohexane, α-pinene oxide, limonene Dioxide, etc. are mentioned.

Moreover, as an alicyclic epoxy compound, a commercial item can be used. As a commercial item, YX8000 (made by Mitsubishi Chemical Corporation), Celoxide 2021P, Celoxide 2081, Celoxide 2000, Celoxide 3000 (made by Daicel Corporation), etc. are mentioned.

As a compound having an oxetane group in the molecule, 3,7-bis(3-oxetanyl)-5-oxa-nonane, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene , 1,2-bis[(3-ethyl-3-oxetanylmethoxy)methyl]ethane, 1,3-bis[(3-ethyl-3-oxetanylmethoxy)methyl]propane, ethylene glycolbis(3 -Ethyl-3-oxetanylmethyl)ether, triethylene glycolbis(3-ethyl-3-oxetanylmethyl)ether, tetraethylene glycolbis(3-ethyl-3-oxetanylmethyl)ether, 1, 2-functional aliphatic oxetane compounds such as 4-bis(3-ethyl-3-oxetanylmethoxy)butane and 1,6-bis(3-ethyl-3-oxetanylmethoxy)hexane, 3-ethyl-3- [(Phenoxy)methyl]oxetane, 3-ethyl-3-(hexyloxymethyl)oxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, 3-ethyl-3-(hydroxy And monofunctional oxetane compounds such as methyl)oxetane and 3-ethyl-3-(chloromethyl)oxetane.

As the compound having an oxetane group in the molecule, a commercial item can also be used. As a commercial item, 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether (above, Maruzen Petrochemical company make);

Aaronoxetane OXT-121, OXT-221, EXOH, POX, OXA, OXT-101, OXT-211, OXT-212 (above, manufactured by Toa Synthetic Corporation);

Eternacol OXBP and OXTP (above, manufactured by Ube Hungsan), and the like.

Among these, a liquid compound at 25°C is preferable from the viewpoint of obtaining an adhesive having more excellent sheet workability (film forming property) and a cured product of an adhesive having more excellent adhesive strength. Further, it is preferable that the cyclic ether group is an oxysilane group. Among the compounds (epoxy compounds) in which the cyclic ether group is an oxysilane group, an alicyclic epoxy compound is preferable from the viewpoint of adjusting the properties of the cured product of the adhesive and preventing coloring, and from the viewpoint of improving the reactivity of photocationic polymerization, cycloalkene Oxide compounds are preferred.

Further, a compound having two or more cyclic ether groups in the molecule, such as a polyfunctional epoxy compound and a bifunctional aliphatic oxetane compound, is preferable from the viewpoint of improving the curability of the sheet-like adhesive.

The molecular weight of the compound having a cyclic ether group is usually 100 to 5,000, preferably 200 to 4,000.

The cyclic ether equivalent of the compound having a cyclic ether group is preferably 100 g/eq or more and 500 g/eq or less, and more preferably 115 g/eq or more and 300 g/eq or less.

When the cyclic ether equivalent of the compound having a cyclic ether group contained in the sheet-like adhesive is in the above range, a sealing material having strong adhesive strength and excellent curability can be efficiently obtained.

These compounds having a cyclic ether group can be used alone or in combination of two or more.

The cyclic ether equivalent in the present invention means a value obtained by dividing the molecular weight by the number of cyclic ether groups.

When the sheet-like adhesive of the present invention contains a binder resin described later, the content of the compound having a cyclic ether group is preferably 20 to 180 parts by mass, more preferably 40 to 140 parts by mass, based on 100 parts by mass of the binder resin. It is a mass part.

By setting the content of the compound having a cyclic ether group in the above range, it becomes easy to obtain a cured product of the adhesive layer having more excellent adhesive strength.

The content of the component (A) in the sheet-like adhesive of the present invention is preferably 20 to 80% by mass, and 25 to 80% by mass as a solid content (non-volatile content, including a liquid one) with respect to the entire adhesive. 70 mass% is more preferable, and 30 to 65 mass% is particularly preferable.

When the content of the component (A) of the sheet-like adhesive of the present invention is in the above range, it becomes easy to adjust the adhesive force of the sheet-like adhesive after irradiation with ultraviolet rays.

((B) component: photocationic polymerization initiator)

The sheet-like adhesive of the present invention contains a photocationic polymerization initiator as component (B). Thereby, it becomes easy to adjust the adhesive force of the sheet-like adhesive after ultraviolet irradiation.

The photocationic polymerization initiator is a compound that generates cation species by irradiation with active energy rays and initiates the curing reaction of the cation curable compound, and consists of a cation moiety that absorbs active energy rays and an anion moiety that is a source of acid. .

Examples of the photocationic polymerization initiator include sulfonium salt compounds, iodonium salt compounds, phosphonium salt compounds, ammonium salt compounds, antimonate compounds, diazonium salt compounds, selenium salt compounds, oxonium salt compounds, And bromine salt compounds. Among these, from the viewpoint of excellent compatibility with the component (A) and excellent storage stability of the resulting adhesive, a sulfonium salt compound is preferable, and an aromatic sulfonium salt compound having an aromatic group is more preferable.

Examples of sulfonium salt compounds include triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, 4,4'-bis[diphenyl Sulfonio]diphenylsulfide-bishexafluorophosphate, 4,4'-bis[di(β-hydroxyethoxy)phenylsulfonio]diphenylsulfide-bishexafluoroantimonate, 7 -[Di(p-toluyl)sulfonio]-2-isopropylthioxanthonehexafluorophosphate, 7-[di(p-toluyl)sulfonio]-2-isopropylthioxanthonehexafluoro Roantimonate, 7-[di(p-toluyl)sulfonio]-2-isopropyltetrakis(pentafluorophenyl)borate, phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfur Pide-hexafluorophosphate, phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluoroantimonate, 4-tert-butylphenylcarbonyl-4'-diphenylsulfonio- Diphenylsulfide-hexafluorophosphate, 4-tert-butylphenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluoroantimonate, 4-tert-butylphenylcarbonyl-4 '-Diphenylsulfonio-diphenylsulfide-tetrakis(pentafluorophenyl)borate, thiophenyldiphenylsulfoniumhexafluoroantimonate, thiophenyldiphenylsulfoniumhexafluorophosphate, 4-{ 4-(2-chlorobenzoyl)phenylthio}phenylbis(4-fluorophenyl)sulfoniumhexafluoroantimonate, a halide of thiophenyldiphenylsulfoniumhexafluoroantimonate, 4,4', 4"-tri(β-hydroxyethoxyphenyl)sulfoniumhexafluoroantimonate, 4,4'-bis[diphenylsulfonio]diphenylsulfide-bishexafluoroantimonate, diphenyl [4-(phenylthio)phenyl]sulfoniumtrifluorotrispentafluoroethylphosphite, tris[4-(4-acetylphenylsulfanyl)phenyl]sulfoniumtris[(trifluoromethyl)sulfonyl]meta Need, etc. are mentioned.

Examples of iodonium salt compounds include diphenyliodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, and di(4-nonylphenyl)iodonium Hexafluorophosphate, (tricumyl) iodonium tetrakis (pentafluorophenyl) borate, etc. are mentioned.

Examples of the phosphonium salt compound include tri-n-butyl(2,5-dihydroxyphenyl)phosphonium bromide, hexadecyltributylphosphonium chloride, and the like.

Examples of the ammonium salt compound include benzyl trimethyl ammonium chloride, phenyl tributyl ammonium chloride, and benzyl trimethyl ammonium bromide.

Examples of antimonate compounds include triphenylsulfoniumhexafluoroantimonate, p-(phenylthio)phenyldiphenylsulfoniumhexafluoroantimonate, and 4-chlorphenyldiphenylsulfoniumhexafluoroantimonate. , Bis[4-(diphenylsulfonio)phenyl]sulfidebishexafluoroantimonate, diallyliodoniumhexafluoroantimonate, and the like.

These photocationic polymerization initiators can be used alone or in combination of two or more.

Moreover, as a photocationic polymerization initiator, a commercial item can be used. Commercially available products include Cyracure UVI-6970, Cyracure UVI-6974, Cyracure UVI-6990, Cyracure UVI-950 (above, manufactured by Union Carbide), Irgacure 250, Irgacure 261, Irgacure 264 (above, manufactured by Chiba Specialty Chemicals), SP-150, SP-151, SP-170, Optomer SP-171 (above, manufactured by ADEKA), CG-24-61 (Chiba Specialty) Chemicals), DAICAT II (manufactured by Daicel), UVAC1590, UVAC1591 (above, manufactured by Daicel-Sytech), CI-2064, CI-2639, CI-2624, CI-2481, CI-2734, CI -2855, CI-2823, CI-2758, CIT-1682 (above, manufactured by Nippon Soda), PI-2074 (manufactured by Rhodia), FFC509 (manufactured by 3M), BBI-102, BBI-101, BBI-103 , MPI-103, TPS-103, MDS-103, DTS-103, NAT-103, NDS-103 (above, manufactured by Midori Chemical), CD-1010, CD-1011, CD-1012 (manufactured by Sartomer), CPI -100P, CPI-101A, CPI-200K, CPI-310B (above, manufactured by San Apro), and the like.

The content of the photocationic polymerization initiator is usually 0.1 to 10 parts by mass, preferably 0.3 to 8 parts by mass, and more preferably 0.5 to 4.5 parts by mass per 100 parts by mass of the component (A).

By setting the content of the photocationic polymerization initiator in the above range, it becomes easy to adjust the adhesive strength of the sheet-like adhesive after ultraviolet irradiation.

The sheet-like adhesive of the present invention may contain components other than the components (A) and (B). Examples of components other than the component (A) and component (B) include a binder resin, a tackifier, and a silane coupling agent.

〔Binder resin〕

When the sheet-like adhesive of the present invention contains a binder resin, excellent sheet processability (film-forming property) is imparted to the composition for forming the sheet-like adhesive, and a sheet-like adhesive having a desired thickness can be efficiently formed.

As the binder resin, from the viewpoint of excellent compatibility with the component (A), one or two or more selected from a modified polyolefin resin and a phenoxy resin is preferable.

In the case of using a modified polyolefin resin, it becomes possible to maintain low moisture permeability while the polyolefin as a main material is inserted into the cured structure. Further, in the case of using a phenoxy resin, it is possible to maintain a high modulus of elasticity of the cured product of the sheet-like adhesive, and it is preferable because the reliability of the electronic device encapsulant in a high temperature environment is improved.

When the sheet-like adhesive of the present invention contains a binder resin, the content is preferably 30 to 80% by mass and more preferably 40 to 70% by mass with respect to the entire sheet-like adhesive.

By containing the binder resin in such a range, excellent sheet processability (film forming property) is imparted to the composition for forming the sheet-like adhesive, and a sheet-like adhesive having a desired thickness can be efficiently formed.

(Modified polyolefin resin)

The modified polyolefin resin is a polyolefin resin in which a functional group is introduced, obtained by subjecting a polyolefin resin as a precursor to a modification treatment using a modifier.

The polyolefin resin refers to a polymer containing a repeating unit derived from an olefinic monomer. The polyolefin resin may be a polymer composed of only one or two or more repeating units derived from an olefinic monomer, or a polymer composed of a repeating unit derived from an olefinic monomer and a repeating unit derived from another monomer copolymerizable with the olefinic monomer. .

As the olefinic monomer, an α-olefin having 2 to 8 carbon atoms is preferable, ethylene, propylene, 1-butene, isobutylene, or 1-hexene is more preferable, and ethylene or propylene is still more preferable.

As another monomer copolymerizable with the olefinic monomer, vinyl acetate, (meth)acrylic acid ester, styrene, etc. are mentioned. Here, "(meth)acrylic acid" represents acrylic acid or methacrylic acid (the same applies hereinafter).

Polyolefin resins include ultra low density polyethylene (VLDPE), low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene (PP), ethylene-propylene copolymer Polymers, olefin elastomers (TPO), ethylene-vinyl acetate copolymers (EVA), ethylene-(meth)acrylic acid copolymers, and ethylene-(meth)acrylic acid ester copolymers.

The modifier used for the modification treatment of the polyolefin resin is a compound having a functional group in the molecule.

As a functional group, a carboxyl group, a carboxylic anhydride group, a carboxylic acid ester group, a hydroxyl group, an epoxy group, an amide group, an ammonium group, a nitrile group, an amino group, an imide group, an isocyanate group, an acetyl group, a thiol group, an ether group, a thioether group , A sulfone group, a phosphone group, a nitro group, a urethane group, an alkoxysilyl group, a silanol group, and a halogen atom. Among these, a carboxyl group, a carboxylic anhydride group, a carboxylic acid ester group, a hydroxyl group, an ammonium group, an amino group, an imide group, an isocyanate group, and an alkoxysilyl group are preferable, and a carboxylic anhydride group and an alkoxysilyl group are more preferable, and carboxyl Acid anhydride groups are particularly preferred.

The compound having a functional group may have two or more types of functional groups in the molecule.

Examples of the modified polyolefin-based resin include acid-modified polyolefin-based resins and silane-modified polyolefin-based resins, and from the viewpoint of obtaining more excellent effects of the present invention, acid-modified polyolefin-based resins are preferred.

The acid-modified polyolefin-based resin refers to a polyolefin resin that is graft-modified with an acid or an acid anhydride. For example, what made a polyolefin resin react with an unsaturated carboxylic acid or an unsaturated carboxylic anhydride, and introduced a carboxyl group or an acid anhydride group (graft modification) is mentioned.

Examples of the unsaturated carboxylic acid reacted with the polyolefin resin include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaconic acid, tetrahydrophthalic acid, and aconitic acid. Examples of the unsaturated carboxylic anhydride include maleic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, norbornenedicarboxylic anhydride, and tetrahydrophthalic anhydride.

These can be used alone or in combination of two or more.

Among these, maleic anhydride is preferable because an adhesive having more excellent sheet workability (film forming property) and a cured product of a sheet-like adhesive having more excellent adhesive strength can be easily obtained.

The amount of the unsaturated carboxylic acid or unsaturated carboxylic anhydride reacted with the polyolefin resin is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, and still more preferably 0.2 per 100 parts by mass of the polyolefin resin. It is-1 part by mass. The sheet-like adhesive containing the acid-modified polyolefin-based resin thus obtained tends to obtain a cured product having more excellent adhesive strength.

As the acid-modified polyolefin-based resin, a commercial item can be used. As a commercial item, for example, Admer (registered trademark) (manufactured by Mitsui Chemicals), Unistol (registered trademark) (manufactured by Mitsui Chemicals), BondyRam (manufactured by Polyram), orevac (registered trademark) (manufactured by ARKEMA), Modic (registered trademark) (manufactured by Mitsubishi Chemical Corporation) and the like.

The silane-modified polyolefin-based resin refers to a polyolefin resin that is graft-modified with an unsaturated silane compound. The silane-modified polyolefin resin has a structure in which an unsaturated silane compound as a side chain is graft copolymerized with a polyolefin resin as a main chain. For example, a silane-modified polyethylene resin and a silane-modified ethylene-vinyl acetate copolymer are mentioned, and silane-modified polyethylene resins such as silane-modified low-density polyethylene, silane-modified ultra-low-density polyethylene, and silane-modified linear low-density polyethylene are preferred.

As the unsaturated silane compound reacted with the polyolefin resin, a vinyl silane compound is preferable. As a vinylsilane compound, vinyl trimethoxysilane, vinyl triethoxysilane, vinyl tripropoxysilane, vinyl triisopropoxysilane, vinyl tributoxysilane, vinyl tripentyloxysilane, vinyl triphenoxysilane, vinyl Tribenzyloxysilane, vinyltrimethylenedioxysilane, vinyltriethylenedioxysilane, vinylpropionyloxysilane, vinyltriacetoxysilane, vinyltricarboxysilane, and the like.

These can be used alone or in combination of two or more.

In addition, conditions in the case of graft polymerization of the unsaturated silane compound to the polyolefin resin as the main chain may employ a known conventional method of graft polymerization.

The amount of the unsaturated silane compound to be reacted with the polyolefin resin is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 7 parts by mass, and still more preferably 0.5 to 5 parts by mass per 100 parts by mass of the polyolefin resin. The sheet-like adhesive containing a silane-modified polyolefin-based resin tends to obtain a cured product having more excellent adhesive strength.

As the silane-modified polyolefin resin, a commercial item can be used. As a commercial item, Linclone (registered trademark) (manufactured by Mitsubishi Chemical Corporation), etc. are mentioned, for example. Among these, a low-density polyethylene-based linclone, a linear low-density polyethylene-based linclone, an ultra-low-density polyethylene-based linclone, and an ethylene-vinyl acetate copolymer-based linclone can be preferably used.

Modified polyolefin-based resins can be used alone or in combination of two or more.

The weight average molecular weight (Mw) of the modified polyolefin-based resin is preferably 10,000 to 300,000, more preferably 20,000 to 150,000.

When the weight average molecular weight (Mw) of the modified polyolefin resin is in such a range, it is easy to adjust its properties while imparting excellent film-forming properties to the composition for forming a sheet-like adhesive.

The weight average molecular weight (Mw) of the modified polyolefin resin can be obtained as a standard polystyrene conversion value by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

(Phenoxy resin)

Phenoxy resin is a polymer whose main chain is a polyaddition structure of an aromatic diol and an aromatic diglycidyl ether.

As the phenoxy resin, depending on the kind of the main chain skeleton, bisphenol A-type phenoxy resin, bisphenol F-type phenoxy resin, bisphenol A-bisphenol F-type phenoxy resin, bisphenol E-type phenoxy resin, and the like may be mentioned.

The phenoxy resin can be obtained by reaction of a bisphenol or biphenol compound with an epihalohydrin such as epichlorohydrin, or a reaction of a bisphenol or biphenol compound with a liquid epoxy resin.

As a phenoxy resin, a commercial item can be used. Commercially available products, brand names: PKHC, PKHH, PKHJ (all manufactured by Tomoe Chemical), brand names: Epicoat 4250, Epicoat 1255HX30, Epicoat 5580BPX40 (all manufactured by Nippon Explosives), brand names: YP-50, YP50S, YP-55 , YP-70 (all manufactured by Toto Hwaseong), brand names: JER 1256, 4250, YX6954BH30, YX7200B35, YL7290BH30 (all manufactured by Mitsubishi Chemical), and the like.

The weight average molecular weight (Mw) of the phenoxy resin is usually 10,000 to 200,000, preferably 20,000 to 100,000, and more preferably 30,000 to 80,000. When the weight average molecular weight of the phenoxy resin is too small, the supportability of the sheet-like adhesive is weakened and the fragility tends to be strong, and when it is too large, the melt viscosity is increased and handling property is liable to be poor.

In addition, in the present specification, when the phenoxy resin has an epoxy group, the weight average molecular weight (Mw) of 10,000 or less is used as the component (A): a compound having a cyclic ether group, and the weight average molecular weight (Mw) What is more than this 10,000 is set as a phenoxy resin.

The weight average molecular weight (Mw) of a phenoxy resin can be calculated|required as a standard polystyrene conversion value by performing gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

〔Adhesion imparting agent〕

The sheet-like adhesive of the present invention may contain a tackifier in addition to the (A) component and (B) component, and the binder resin as desired. By containing the tackifier, it becomes easy to adjust the storage modulus of the sheet-like adhesive.

Examples of the tackifier include rosin resins such as rosin resins, rosin ester resins, and rosin-modified phenol resins; Hydrogenated rosin-type resin obtained by hydrogenating these rosin-type resins;

Terpene resins such as terpene resins, aromatic modified terpene resins, and terpenephenol resins; Hydrogenated terpene resins obtained by hydrogenating these terpene resins;

α-methylstyrene single polymer resin, α-methylstyrene/styrene copolymer resin, styrene monomer/aliphatic monomer copolymer resin, styrene monomer/α-methylstyrene/aliphatic monomer copolymer resin, styrene monomer single Styrene-based resins, such as a polymerization-based resin and a styrene-based monomer/aromatic-based monomer copolymerized resin; Hydrogenated styrene resin obtained by hydrogenating these styrene resins;

C5 petroleum resin obtained by copolymerizing C5 fractions such as pentene, isoprene, piperine, and 1.3-pentadiene produced by thermal decomposition of petroleum naphtha, and hydrogenated petroleum resin of the C5 petroleum resin;

C9-based petroleum resin obtained by copolymerizing C9 fractions such as indene and vinyl toluene produced by thermal decomposition of petroleum naphtha, and hydrogenated petroleum resin of the C9-based petroleum resin; And the like. Among these, a styrenic resin is preferable, and a styrenic monomer/aliphatic monomer copolymer resin is more preferable.

These tackifiers can be used alone or in combination of two or more.

As a tackifier, a commercial item can be used. Commercially available products include terpene-based resins such as YS resin P, A series, Clearon (registered trademark) P series (manufactured by Yasuhara Chemical), and Picolite A, C series (manufactured by PINOVA);

Aliphatic petroleum resins, such as Quinton (registered trademark) A, B, R, CX series (manufactured by Nippon Xeon);

Styrene resins, such as FTR (registered trademark) series (manufactured by Mitsui Chemicals);

Alcon P, M series (manufactured by Arakawa Chemical), ESCOREZ (registered trademark) series (manufactured by Exxon Mobil-Chemical Corporation), EASTOTAC (registered trademark) series (manufactured by Eastman Chemical), IMARV (registered trademark) series (Idemitsu Heungsan Corporation) Alicyclic petroleum resins such as manufacturing);

Ester resins, such as a formal series (manufactured by PINOVA), Pencel (registered trademark) A series, ester gum, super ester, fine crystal (registered trademark) (manufactured by Arakawa Chemical Industries, Ltd.); And the like.

From the viewpoint of imparting excellent tackiness, the weight average molecular weight (Mw) of the tackifier is preferably 100 to 10,000, and more preferably 500 to 5,000.

From the viewpoint of imparting excellent tackiness, the softening point of the tackifier is preferably 50 to 160°C, more preferably 60 to 140°C, and still more preferably 70 to 130°C.

When the sheet-like adhesive of the present invention contains a tackifier, the content is preferably 1 to 200 parts by mass, more preferably 10 to 150 parts by mass, based on 100 parts by mass of the component (A).

[Silane coupling agent]

The sheet-like adhesive of the present invention may contain a silane coupling agent in addition to the above component (A) and component (B) and, if desired, a binder resin and a tackifier.

By containing a silane coupling agent, it becomes easy to obtain a cured product of a sheet-like adhesive having more excellent adhesive strength.

As a silane coupling agent, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, Silane coupling agents having a (meth)acryloyl group such as 3-acryloxypropyl trimethoxysilane;

Silane coupling agents having a vinyl group such as vinyl trimethoxy silane, vinyl triethoxy silane, dimethoxy methyl vinyl silane, diethoxy methyl vinyl silane, trichloro vinyl silane, and vinyl tris (2-methoxyethoxy) silane;

2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, etc. Silane coupling agent which has an epoxy group of;

silane coupling agents having a styryl group such as p-styryl trimethoxysilane and p-styryl triethoxysilane;

N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltri Ethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3 Silane coupling agents having an amino group such as hydrochloride salt of -aminopropyltrimethoxysilane and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane;

A silane coupling agent having a ureido group such as 3-ureidopropyl trimethoxysilane and 3-ureidopropyl triethoxysilane;

Silane coupling agents having a halogen atom such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane;

Silane coupling agents having a mercapto group, such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane;

A silane coupling agent having a sulfide group such as bis(trimethoxysilylpropyl)tetrasulfide and bis(triethoxysilylpropyl)tetrasulfide;

A silane coupling agent having an isocyanate group such as 3-isocyanate propyl trimethoxysilane and 3-isocyanate propyl triethoxysilane;

Silane coupling agents having an allyl group such as allyl trichlorosilane, allyl triethoxysilane, and allyl trimethoxysilane;

Silane coupling agents having a hydroxyl group such as 3-hydroxypropyltrimethoxysilane and 3-hydroxypropyltriethoxysilane; And the like.

These silane coupling agents can be used alone or in combination of two or more.

When the sheet-like adhesive of the present invention contains a silane coupling agent, the content is preferably 0.01 to 5 parts by mass, more preferably 0.02 to 3 parts by mass, based on 100 parts by mass of the component (A).

By setting the content of the silane coupling agent in the above range, it becomes easier to obtain a cured product of a sheet-shaped adhesive having more excellent adhesive strength.

Further, the sheet-like adhesive of the present invention may further contain components other than the tackifier and the silane coupling agent within a range that does not interfere with the effects of the present invention.

Examples of components other than the tackifier and the silane coupling agent include an antistatic agent, a stabilizer, an antioxidant, a plasticizer, a lubricant, and a colored pigment. These contents may be appropriately determined according to the purpose.

The sheet-like adhesive of the present invention can be formed using the prepared adhesive composition by appropriately mixing and stirring a predetermined component according to a conventional method, as described later.

(Sheet-shaped adhesive)

From the viewpoint of protection from the external environment, the sheet-like adhesive of the present invention preferably has a release film on at least one side, and may have a release film on both sides.

In addition, the sheet-like adhesive of the present invention having a release film on at least one surface shows a state before use, and when using the sheet-like adhesive of the present invention, the release film is usually peeled off. When the sheet-like adhesive has a release film on both sides, usually, a release film having a low peeling force is peeled off first.

As the release film, usually, a resin film can be used.

As the resin component of the resin film, polyimide, polyamide, polyamideimide, polyphenylene ether, polyether ketone, polyether ether ketone, polyolefin, polyester, polycarbonate, polysulfone, polyether sulfone, polyphenylene sulfone Pyide, polyarylate, acrylic resin, cycloolefin polymer, aromatic polymer, polyurethane polymer, and the like. Among these, a polyester resin is preferable, and as a resin film, a polyester film is preferable. As a polyester film, a polyethylene terephthalate film which is excellent in heat resistance and ease of handling, and the transmittance of ultraviolet rays is high about 80% at a wavelength of 365 nm is more preferable.

Examples of the release agent include rubber-based elastomers such as silicone-based resins, olefin-based resins, isoprene-based resins, and butadiene-based resins, long-chain alkyl-based resins, alkyd-based resins, and fluorine-based resins.

The thickness of the release film is preferably 10 to 300 µm, more preferably 10, from the viewpoint of improving heat resistance, or from the viewpoint of not obstructing the sheet-like adhesive by transmitting ultraviolet rays through the release film. It is -200 micrometers, More preferably, it is 15-100 micrometers. From the viewpoint of facilitating the initiation of photocationic polymerization by transmitting the release film to the sheet-like adhesive of the present invention by irradiating UV rays with a wavelength of 365 nm, the transmittance of the UV rays having a wavelength of 365 nm of the release film is 65%. It is preferable that it is above, and it is preferable that it is 70% or more. Further, when the release film is made of a polyethylene terephthalate film as a base material, when the wavelength of ultraviolet rays is less than 330 nm, the transmittance is markedly lowered.

The thickness of the sheet-like adhesive is usually 1 to 50 µm, preferably 5 to 30 µm. A sheet-like adhesive having a thickness within the above range is preferably used as a sheet-like sealing material.

The thickness of the sheet-like adhesive can be measured in accordance with JIS K 7130 (1999) using a known thickness meter. In addition, the thickness of the sheet-like adhesive is the thickness excluding the thickness of the release film.

Even after irradiation of ultraviolet rays, the sheet-like adhesive of the present invention has adhesive strength and strongly adheres to an electronic device or a functional film, and peeling does not occur at the time of affixing or after the affixing. Therefore, it can be suitably used as a sealing material for an electronic device encapsulating body, in particular, an electronic device encapsulating body having a functional film non-transmitting ultraviolet rays on its surface.

When the sheet-like adhesive of the present invention has a release film on at least one side, on the opposite side, it is bonded with a 23 µm thick polyethylene terephthalate film deposited with aluminum to prepare a laminate, and a release film is applied. In the combined state, from the release film side, UV rays having a wavelength of 365 nm were irradiated to the laminate under conditions of illuminance: 50 mW/cm 2 and light quantity: 200 mJ/cm 2, and after 3 minutes, the release film was peeled from the laminate. Then, the exposed layer of the sheet-like adhesive was opposed to the soda glass plate, affixed to the soda glass plate by reciprocating a roll of 2 kg on the laminated body, and stored for 24 hours in an environment of 50% relative humidity at 23°C. It is preferable that it is 3 N/25 mm or more, and, as for the adhesive force with respect to, it is more preferable that it is 5 N/25 mm or more.

The adhesive force to the glass is measured by the method described in Examples (180° peeling test).

(Method of manufacturing sheet-like adhesive)

The method for producing the sheet-like adhesive of the present invention is not particularly limited. For example, it can be manufactured using a cast method.

The method of producing a sheet-like adhesive by a cast method is a known method, applying the adhesive composition to the peeling-treated release layer surface of the release film, and drying the obtained coating film to obtain a sheet-like adhesive with a release film. To get.

The adhesive composition can be prepared by mixing the component (A) and the component (B) and, if desired, other components by a known method and stirring.

When a solvent is used in the preparation of the adhesive composition, the viscosity of the adhesive composition can be appropriately adjusted according to the amount of the solvent used.

Examples of the solvent include aliphatic hydrocarbon solvents such as n-hexane and n-heptane; Aromatic hydrocarbon solvents such as toluene and xylene; Halogenated hydrocarbon solvents such as dichloromethane, ethylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, and monochlorobenzene;

Alcohol solvents such as methanol, ethanol, propanol, butanol, and propylene glycol monomethyl ether; Ketone solvents such as acetone, methyl ethyl ketone, 2-pentanone, isophorone, and cyclohexanone; Ester solvents such as ethyl acetate and butyl acetate; Cellosolve solvents such as ethyl cellosolve; Ether solvents such as 1,3-dioxolane; And the like.

These solvents can be used alone or in combination of two or more.

The content of the solvent can be appropriately determined in consideration of coating properties, film thickness, and the like.

The release film used for the production of the sheet-like adhesive functions as a support in the production process of the sheet-like adhesive, and functions as a release film for the above-described sheet-like adhesive until the sheet-like adhesive is used. .

As a method of coating the adhesive composition, for example, a spin coating method, a spray coating method, a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method, a gravure coating method, and the like may be mentioned. .

As a method of drying the coating film of the adhesive composition, a conventionally known drying method such as hot air drying, hot roll drying, infrared irradiation, etc. can be mentioned.

Conditions for drying the coating film are, for example, at 80 to 150°C for 30 seconds to 5 minutes.

[Adhesive film for electronic device sealing]

The adhesive film for electronic device sealing of the present invention has a functional film having a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm, and an adhesive layer made of a sheet-like adhesive containing the components (A) and (B).

The adhesive film for electronic device sealing of the present invention is used to seal an electronic device through the sheet-like adhesive.

As "functional film in which the transmittance of ultraviolet rays with a wavelength of 365 nm is 60% or less" and "sheet-like adhesive", the same ones as described above can be used. The adhesive film for electronic device sealing of the present invention can be obtained by bonding a functional film and a sheet-like adhesive, for example, as described later.

The adhesive film for electronic device sealing of the present invention may have at least an adhesive layer composed of the functional film and a sheet-like adhesive, may consist of only one layer of the adhesive layer, or a laminate of a plurality of adhesive layers. Alternatively, it may have a layer other than the adhesive.

Other layers include a primer layer that improves the adhesion of the interface between the adhesive layer and the functional film, a functional coat layer or a protective film formed on the side that does not have the adhesive layer of the functional film, and charging that can be formed on both sides of the functional film. Prevention layer, stress relief layer, etc. are mentioned.

In addition, when a plurality of adhesive layers are used in the adhesive film for electronic device sealing of the present invention, each adhesive layer may have the same composition or different compositions.

It is preferable that the adhesive film for electronic device sealing of the present invention has a release film on the surface of the adhesive layer on the side to which the functional film is not adhered, and the release film is the same as that used for the sheet-like adhesive described above. It is desirable.

The thickness of the adhesive film for sealing electronic devices of the present invention is usually 6 to 270 µm. In addition, the thickness of the adhesive film for electronic device sealing is the thickness excluding members to be peeled off before use, such as a peeling film and a protective film.

The adhesive film for sealing an electronic device of the present invention has adhesive strength even after irradiation with ultraviolet rays, strongly adheres to the electronic device, and does not cause peeling at the time of sticking or after sticking. It can be preferably used as a sealing material for an electronic device sealing body having a film.

When the adhesive film for electronic device sealing of the present invention has a release film on the surface of the adhesive layer on the side where the functional film is not bonded, the release film side in a state in which the release film is bonded to the adhesive film for device sealing From this, ultraviolet rays having a wavelength of 365 nm were irradiated under conditions of illuminance: 50 mW/cm 2 and light quantity: 200 mJ/cm 2, and after 3 minutes, the release film was peeled from the adhesive film for sealing electronic devices, and the exposed adhesive layer The adhesive force to the soda glass plate after facing the soda glass plate, attaching it to the soda glass plate by reciprocating 1 reciprocating roll of 2 kg on the adhesive film for device sealing, and storing at 23° C. in an environment of 50% relative humidity for 24 hours was 3 It is preferable that it is N/25 mm or more, and it is more preferable that it is 5 N/25 mm or more.

The adhesive force to the glass is measured by the method described in Examples (180° peeling test).

[Production method of electronic device encapsulation body]

The electronic device sealing body of the present invention, for example, can be manufactured as follows.

Hereinafter, it demonstrates, referring drawings.

(Manufacturing method 1)

The electronic device of the present invention includes (α1) irradiating ultraviolet rays from the surface side closer to the adhesive layer than the functional film to the adhesive film for electronic device sealing of the present invention, and

(β1) having a step of attaching the adhesive film to an electronic device,

It can be manufactured by performing the (α1) step before the (β1) step.

More specifically, it is carried out as follows.

First, as shown in Fig. 2(a), a sheet-like adhesive 2a is prepared.

In this case, the sheet-like adhesive 2a can be stored as an adhesive film having a double-sided release film in which a release film is laminated on both sides of the front and back.

Next, on one side of the obtained sheet-like adhesive 2a, a functional film 1 having a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm is laminated to obtain a laminate 4a shown in Fig. 2(b).

In addition, when the sheet-like adhesive 2a is an adhesive film with a double-sided release film attached, the release film on one side is peeled off and bonded to the functional film 1. In this case, a laminate having a layer structure of the functional film (1)/sheet-like adhesive/peel film is obtained.

Next, as shown in Fig. 2(c), from the side opposite to the side on which the functional film 1 of the laminate 4a is laminated, the sheet-like adhesive is irradiated with ultraviolet rays, and the sheet-like adhesive 2a is photocured. Initiate the reaction. At this time, the photocuring reaction is started among the sheet-like adhesives, but since the reaction rate of photocationic polymerization is relatively slow, the curing reaction is not completed, and the sheet-like adhesive has sufficient adhesive strength (Fig. 2). (c) Middle, sheet-like adhesive (2b)).

In addition, in the case of using a laminate having a layer structure of the functional film (1)/sheet-like adhesive/release film, and when the release film is UV-transmitting, the release film on the sheet-like adhesive is not peeled off, It is preferable in terms of handling property to irradiate ultraviolet rays from the film side.

Here, "having ultraviolet ray transmittance" refers to a property that transmits 65% or more, preferably 70% or more of the ultraviolet rays having a wavelength of 365 nm (the same applies hereinafter).

Specific examples of the ultraviolet source include light sources such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, and a metal halide lamp. Further, as the wavelength of the ultraviolet rays to be irradiated, a wavelength range of 190 to 380 nm can be used. In the case of irradiating ultraviolet rays from the release film side without peeling the release film of the laminate having the layer configuration of the functional film (1)/sheet adhesive/ultraviolet ray-transmitting release film, the release film is a polyethylene terephthalate film. If it is used as a base material, the transmittance of ultraviolet rays of the peeling film is remarkably lowered in a region where the wavelength of ultraviolet rays is less than 330 nm. Therefore, it is preferable to irradiate ultraviolet rays in the wavelength range of 330 to 380 nm.

The type, amount of irradiation, irradiation time, and the like of ultraviolet rays can be appropriately determined depending on the constituent components of the sheet-like adhesive to be irradiated or the content of each constituent component.

The irradiation illuminance is preferably about 20 to 1000 mJ/cm 2 and an amount of light about 50 to 1000 mJ/cm 2.

In addition, the irradiation time is usually 0.1 to 1000 seconds, preferably about 1 to 500 seconds.

Thereafter, as shown in Fig. 2(d), the target electronic device sealing body 10 can be obtained by bonding the sheet-like adhesive 2b and the electronic device in a state in which the curing reaction has not been completed.

After irradiation with ultraviolet rays, the time until bonding to the electronic device is sufficient as long as the sheet-like adhesive irradiated with ultraviolet rays is in a state in which the curing reaction has not been completed and has sufficient adhesive strength.

The time until bonding to the electronic device after irradiation with ultraviolet rays is not particularly limited, but is usually 1 minute to 5 hours, preferably 5 to 60 minutes.

In the sheet-like adhesive 2b in a state in which the curing reaction is not completed, the photocuring reaction proceeds in the sheet-like adhesive even after bonding the electronic devices, and the sheet-like adhesive is completely cured over time ( It becomes the cured adhesive layer (2)).

As described above, since the sheet-like adhesive of the present invention has sufficient adhesiveness even after irradiation with ultraviolet rays or while the curing reaction is not sufficiently advanced, it strongly adheres to the electronic device as an adherend and adheres to it, or Peeling after sticking can be prevented, and the sheet-like adhesive cures over time, and finally, an electronic device sealing body excellent in durability can be obtained.

(Manufacturing method 2)

In addition, the electronic device encapsulation body of the present invention includes (α2) a step of irradiating an ultraviolet ray to a sheet-like adhesive comprising the following components (A) and (B),

(β2) having a step of attaching the sheet-like adhesive to a functional film or an electronic device,

It can also be manufactured by performing the (?2) process before the (?2) process.

Specifically, this method is implemented as follows.

First, a sheet-like adhesive 2a is prepared. The sheet-like adhesive 2a can be stored as an adhesive film with a double-sided release film in which a release film is laminated on both sides of the front and back.

Next, as shown in FIG. 3(a), ultraviolet rays are irradiated to the sheet-like adhesive 2a, and the photocuring reaction of the sheet-like adhesive 2a is started. In this case, it is preferable to irradiate ultraviolet rays over the release film.

When ultraviolet rays are irradiated, the photocuring reaction is started in the sheet-like adhesive, but since the reaction rate of photocationic polymerization is relatively gentle, the curing reaction is not completed, and the sheet-like adhesive has sufficient adhesive strength.

The kind of ultraviolet rays, irradiation conditions of ultraviolet rays, and the like are the same as those described in Manufacturing Method 1.

Next, by bonding the functional film 1 or the electronic device 3 to one side of the sheet-like adhesive 2b, a state shown in Fig. 3(b) is obtained.

Thereafter, as shown in Fig. 3(c), the side opposite to the side on which the functional film 1 or the electronic device 3 is adhered of the sheet-like adhesive 2b in a state in which the curing reaction is not completed And, by polymerizing the electronic device 3 and the functional film 1, the intended electronic device sealing body 10 can be obtained. That is, in the case where the functional film 1 is bonded to one side of the sheet-like adhesive 2b, the electronic device 3 is bonded to the side opposite to the side on which the functional film 1 is bonded. The device sealing body 10 can be obtained. In addition, in the case where the electronic device 3 is bonded to one side of the sheet-like adhesive 2b, the functional film 1 is bonded to the side opposite to the side on which the electronic device 31 is bonded, thereby e. The device sealing body 10 can be obtained.

Even after bonding the sheet-like adhesive 2b in which the curing reaction has not been completed and the functional film 1 or the electronic device 3, the photocuring reaction proceeds in the layer of the sheet-like adhesive, and over time the sheet The layer of the upper adhesive is in a completely cured state (cured adhesive layer 2).

As described above, the sheet-like adhesive of the present invention strongly adheres to the electronic device as an adherend, since the adhesive layer has sufficient adhesiveness even after irradiating the adhesive layer with ultraviolet rays and while the curing reaction is not sufficiently advanced. Thus, it is possible to prevent the occurrence of peeling at the time of sticking or after sticking, and the adhesive layer hardens over time, and finally, an electronic device sealing body excellent in durability can be obtained.

Example

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

Unless otherwise stated, parts and% in each example are based on mass.

[Transmittance of UV rays with a wavelength of 365 nm of functional film]

The transmittance of ultraviolet rays with a wavelength of 365 nm of the functional film was measured using an ultraviolet visible light transmittance measuring device (manufactured by Shimadzu Corporation, UV-3600).

[Measurement of adhesive strength of adhesive layer after UV irradiation]

From the adhesive film for electronic device sealing with a release film obtained in Examples and Comparative Examples, without peeling the release film, it was cut into a width of 25 mm to obtain a sample. In a 23°C, 50% environment, ultraviolet rays having a wavelength of 365 nm were irradiated from the release film side at an illuminance of 50 mW/cm 2 and an accumulated light amount of 200 mJ/cm 2. The irradiation of ultraviolet rays was performed using a high pressure mercury lamp manufactured by Eye Graphics. In addition, "UVPF-A1" manufactured by Eye Graphics Corporation was used as the light meter.

After the lapse of 3 minutes, the release film was peeled off, the sheet-like adhesive surface of the exposed adhesive layer was overlaid on a 1.1 mm-thick soda glass plate, and a 2 kg roll was reciprocated on the surface of the functional film by pressing. After the electronic device sealing adhesive film was pressed onto a soda glass plate, it was allowed to stand for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%, and then a 180° peeling test was performed at a peel rate of 300 mm/min. Then, the adhesive force was measured.

In the following examples and comparative examples, a compound having a cyclic ether group [component (A)], a photocationic polymerization initiator [component (B)], a binder resin [component (C)], a tackifier, and a silane As the coupling agent, the following were used.

<Compound having a cyclic ether group [component (A)]>

(1) Compound having a cyclic ether group (A-1)

Hydrogenated bisphenol A type epoxy resin [manufactured by Mitsubishi Chemical, brand name: YX8000, cyclic ether equivalent: 205 g/eq, liquid at 25°C]

(2) Compound having a cyclic ether group (A-2)

3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate [manufactured by Daicel Co., Ltd., brand name: Celoxide 2021P, cyclic ether equivalent: 128 to 145 g/eq, at room temperature (23° C.) Liquid]

<Photocationic polymerization initiator [component (B)]>

(1) photocationic polymerization initiator (B-1)

Triarylsulfonium salt [manufactured by San Apro, brand name: CPI-200K, anion: anion having a hexafluorophosphate skeleton]

(2) photocationic polymerization initiator (B-2)

Triarylsulfonium salt (manufactured by San Apro, brand name: CPI-100P)

<Binder resin [(C component)]

(1) Binder resin (C-1)

Acid-modified α-olefin polymer [manufactured by Mitsui Chemicals, brand name: Unistol H-200, weight average molecular weight: 52,000]

(2) Binder resin (C-2)

Phenoxy resin (manufactured by Mitsubishi Chemical, brand name: YX7200B35)

[Example 1]

50 parts by mass of a compound (A-1) having a cyclic ether group, 20 parts by mass of a compound (A-2) having a cyclic ether group, 1 part by mass of a photocationic polymerization initiator (B-1), a photocationic polymerization initiator ( 1.5 parts of B-2), 100 parts by mass of an acid-modified α-olefin polymer (A), and 0.1 parts by mass of a silane coupling agent were dissolved in methyl ethyl ketone to prepare an adhesive composition having a solid content concentration of 30%.

This adhesive composition (1) was coated on the peeling-treated surface of a release film (manufactured by Lintec Co., Ltd., brand name: SP-PET752150, thickness 75 µm), which is a polyethylene terephthalate film subjected to silicone peeling treatment, and the obtained coating film was applied to 2 After drying for a minute, an adhesive layer having a thickness of 30 μm was formed.

On the adhesive layer, as a functional film, a polyethylene terephthalate film (manufactured by Mitsubishi Shindong Co., Ltd., trade name: metallized film, thickness 23 μm) was bonded to the side where metal aluminum was not deposited. , An adhesive film for electronic device sealing was obtained in a state having a release film. The transmittance of this functional film at a wavelength of 365 nm was 0%. Moreover, the adhesive force after ultraviolet irradiation was 12 N/25 mm.

[Example 2]

An adhesive film for electronic device sealing was prepared in the same manner as in Example 1, except that the photocationic polymerization initiator (B-1) was not used and the blending amount of the photocationic polymerization initiator (B-2) was changed to 3.0 parts by mass. Got it. The adhesive force after ultraviolet irradiation was 4 N/25 mm.

[Example 3]

An adhesive film for electronic device sealing was prepared in the same manner as in Example 1, except that the photocationic polymerization initiator (B-1) was not used and the blending amount of the photocationic polymerization initiator (B-2) was changed to 3.5 parts by mass. Got it. The adhesive force after ultraviolet irradiation was 1 N/25 mm.

[Example 4]

In place of the raw material (solid content) of the adhesive composition used in Example 1, 120 parts by mass of the compound (A-2) having a cyclic ether group, (2) 2.5 parts by mass of a photocationic polymerization initiator (B-2), and a binder resin ( C-2) 100 parts by mass of a silane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., trade name: KBM6803) was used in the same manner as in Example 1, except that 0.2 parts by mass of the adhesive composition was used to prepare an adhesive film for sealing an electronic device. . The adhesive force after ultraviolet irradiation was 6 N/25 mm.

One ; Functional film
2a; Sheet-like adhesive
2b; Sheet-like adhesive that has not completed the curing reaction
2 ; Cured adhesive layer
3; Electronic device
4a; Laminate
10; Electronic device encapsulant

Claims (9)

A functional film having a wavelength of 365 nm ultraviolet light transmittance of 60% or less, an electronic device, and a cured adhesive layer sealing between the functional film and the electronic device, and the cured adhesive layer comprises the following (A) component and The electronic device sealing body which is a cured product of a sheet-like adhesive containing component (B).
(A) Compound having a cyclic ether group
(B) photocationic polymerization initiator A sheet-like adhesive comprising the following component (A) and component (B), which is used in the production of the electronic device sealing body according to claim 1.
(A) Compound having a cyclic ether group
(B) photocationic polymerization initiator The method of claim 2,
The sheet-like adhesive has a release film on at least one surface, and an adhesive force to a soda glass plate measured under the following condition (i) is 3 N/25 mm or more.
(i) On the side opposite to the side to which the release film of the sheet-like adhesive is adhered, a laminate was prepared in which a 23 μm-thick polyethylene terephthalate film was deposited with aluminum, and the release film was bonded to each other. , From the release film side, irradiation with ultraviolet rays having a wavelength of 365 nm, illuminance: 50 mW/cm 2, light quantity: 200 mJ/cm 2, and 3 minutes later, the release film was removed from the laminate After peeling, the exposed layer of the sheet-like adhesive was opposed to the soda glass plate, affixed to the soda glass plate by reciprocating a roll of 2 kg on the laminated body, and stored for 24 hours in an environment of 50% relative humidity at 23°C. Perform a 180° peeling test. The method according to claim 2 or 3,
Further, a sheet-like adhesive comprising at least one selected from the group consisting of a modified polyolefin resin and a phenoxy resin. An adhesive film for electronic device sealing, comprising: a functional film having a wavelength of 365 nm and a transmittance of 60% or less of an ultraviolet ray, and an adhesive layer comprising a sheet-like adhesive comprising the following components (A) and (B).
(A) Compound having a cyclic ether group
(B) photocationic polymerization initiator The method of claim 5,
The adhesive film for electronic device sealing has a release film on the surface of the adhesive layer on the side to which the functional film is not adhered, and the adhesive force to the soda glass plate measured under the following condition (ii) is 3 N/25 mm or more. , An adhesive film for sealing electronic devices.
(ii) In the state of bonding the release film to the adhesive film for sealing electronic devices, from the release film side, irradiation with ultraviolet rays having a wavelength of 365 nm under conditions of illuminance: 50 mW/cm 2 and light quantity: 200 mJ/cm 2 And 3 minutes later, the release film is peeled from the adhesive adhesive film for electronic device sealing, the exposed adhesive layer is opposed to a soda glass plate, and a 2 kg roll is reciprocated once on the adhesive film for electronic device sealing. After affixing to a soda glass plate and storing for 24 hours in an environment of 50% relative humidity at 23°C, a 180° peeling test is performed. The method according to claim 5 or 6,
Further, the sheet-like adhesive includes at least one selected from the group consisting of a modified polyolefin resin and a phenoxy resin. (α1) A step of irradiating ultraviolet rays from the surface side closer to the adhesive layer than the functional film to the adhesive film for electronic device sealing according to any one of the above items 5 to 7,
(β1) having a step of attaching the adhesive film to an electronic device,
A method of manufacturing an electronic device encapsulation body in which the step (α1) is performed before the step (β1). (α2) a step of irradiating ultraviolet rays to a sheet-like adhesive comprising the following components (A) and (B), and
(β2) having a step of affixing the sheet-like adhesive to a functional film or electronic device having a transmittance of 60% or less of ultraviolet rays having a wavelength of 365 nm,
A method of manufacturing an electronic device encapsulation body in which the step (α2) is performed before the step (β2).
(A) Compound having a cyclic ether group
(B) photocationic polymerization initiator

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