TW201903103A - Adhesive composition, adhesive sheet and sealing body - Google Patents

Abstract

Provided is an adhesive composition containing: component (A) a modified polyolefin resin; component (B) a polyfunctional epoxy compound which is a liquid at 25 DEG C; and component (C) a polyfunctional epoxy compound which is a solid at 25 DEG C. When the volatile components contained in the adhesive composition are analyzed using the purge and trap method, the amount of volatile antioxidants contained does not exceed 0.2 mg/cm3 in terms of toluene. Also provided are an adhesive sheet having an adhesive layer formed using this adhesive composition, and a sealed body obtained by sealing an object to be sealed with the adhesive sheet. According to the present invention it is possible to provide an adhesive composition which can be easily formed into sheets, and which, when used as a sealant, renders electrode members, organic semiconductors and the like resistant to corrosion, an adhesive sheet having an adhesive layer which hinders corrosion of electrode members and organic semiconductors and is formed using this adhesive composition, and a sealed body obtained by sealing an object to be sealed with the adhesive sheet.

Description

Adhesive composition, adhesive sheet and sealing body

The present invention relates to an adhesive composition which can be easily formed into a thin sheet and is not easily corroded to an electrode member, an organic semiconductor, etc. when used as a sealing material, and an adhesive composition which is formed using the adhesive composition, and does not easily corrode the electrode member, organic semiconductor, etc. The adhesive sheet of the adhesive layer and the sealed object are sealed by the above-mentioned adhesive sheet.

In recent years, organic EL devices have attracted much attention because they are light-emitting devices that can emit light with high luminance by using low-voltage DC driving. However, the organic EL element has a problem that light emission characteristics such as light emission brightness, light emission efficiency, and light emission uniformity tend to decrease over time. The problem of the decrease in light emitting characteristics is considered to be that oxygen and moisture penetrate into the organic EL element and cause deterioration of the electrode and the organic layer. Therefore, a sealing material is used to seal the organic EL element to prevent oxygen and moisture. Infiltrate. As a method for forming such a sealing material, a method using a thermosetting resin sheet is known.

For example, Patent Document 1 describes: (A) a polyisobutylene resin, (B) a polyisoprene resin and / or a polyisobutylene resin having a functional group capable of reacting with an epoxy group, and (C) a tackifying resin. And (D) a resin composition of an epoxy resin; and a resin composition sheet containing the resin composition. Patent Document 1 also describes that the resin composition can be easily thinned, and the obtained resin composition sheet is suitable for sealing organic EL devices. [Antecedent Literature] [Patent Literature]

[Patent Document 1] WO2011 / 062167 (US2012 / 0283375 A1)

(Problems to be solved by the invention)

Patent Document 1 describes that the adhesion of a resin composition is improved by using a tackifying resin. Furthermore, according to the review by the present inventors, it was also found that a resin composition containing a tackifier resin having a high softening point is suitable as a raw material for an adhesive sheet because of its excellent shape retention. However, on the other hand, when the organic EL element is sealed using a resin composition containing a tackifying resin, the organic EL element is liable to deteriorate and black spots are liable to occur.

The present inventors and the like have further studied, and as a result, it has been found that one of the causes of deterioration of the organic EL element may be that the antioxidant corrodes the electrode member, the organic semiconductor, and the like. In addition, since commercially available tackifier resins are generally added with an antioxidant, it is known that if a resin composition obtained by blending a tackifier resin is used to seal an organic EL device, the organic EL device is liable to be deteriorated. The present invention has been made in view of the above-mentioned circumstances, and an object thereof is to provide an adhesive composition that can be easily formed into a thin sheet and does not easily corrode electrode members, organic semiconductors, and the like when used as a sealing material; and is formed by using the adhesive composition. , An adhesive sheet that does not easily corrode an electrode layer, an adhesive layer of an organic semiconductor, and the like; and a sealed body sealed by the above-mentioned adhesive sheet. (Means for solving problems)

The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, they have found that the modified polyolefin-based resin contains a polyfunctional epoxy compound that is liquid at 25 ° C and a polyfunctional epoxy that is solid at 25 ° C. The compound adhesive composition can be easily formed into a thin sheet even without using a tackifying resin, and has excellent sealing ability, and thus completed the present invention.

The reason is that according to the present invention, the following adhesive compositions (1) to (9), adhesive sheets (10) to (12), and sealing bodies (13) and (14) are provided. (1) An adhesive composition, which is an adhesive composition containing the following components (A), (B), and (C); characterized in that the adhesive composition is analyzed by the following air-blow capture method: In the case of the volatile component contained in the volatile component, the content of the volatile antioxidant is 0.2 mg / cm ³ or less in terms of toluene conversion. (A) Component: Modified polyolefin resin (B) Component: Polyfunctional epoxy compound that is liquid at 25 ° C (C) Component: Polyfunctional epoxy compound that is solid at 25 ° C [blowing Capture method] An adhesive layer (18 mm × 18 mm × 12 μm) formed by using an adhesive composition was put into a glass test tube, heated at 120 ° C. for 20 minutes in a helium stream, and continuously collected by a gas trap tube. Gas released from the agent layer. Next, the trapped gas is introduced into a gas phase chromatography mass spectrometer, and a volatile component contained in the adhesive composition is analyzed. At this time, the amount of the volatile antioxidant was quantified from a calibration line made using toluene.

(2) The adhesive composition according to (1), wherein the component (A) is an acid-modified polyolefin resin. (3) The adhesive composition according to (1), wherein the total amount of the component (B) and the component (C) is 100 to 200 parts by mass based on 100 parts by mass of the component (A). (4) The adhesive composition according to (1), wherein the content ratio (mass ratio) of the component (B) to the component (C) is [(B) component: (C) component] = 100: 1 ~ 1: 1. (5) The adhesive composition according to (1), further comprising the following (D) component: (D) Component: an imidazole curing catalyst (6) The adhesive combination according to (5) The content of the component (D) is 1 to 10 parts by mass based on 100 parts by mass of the total amount of the component (B) and the component (C). (7) The adhesive composition according to (1), further comprising the following component (E): (E) component: a silane coupling agent

(8) The adhesive composition according to (7), wherein the content of the component (E) is 0.01 to 10 parts by mass based on 100 parts by mass of the component (A). (9) The adhesive composition according to (1), wherein the volatile antioxidant is a hindered phenol antioxidant. (10) An adhesive sheet, which is an adhesive sheet having an adhesive layer, wherein the adhesive layer is formed using the adhesive composition according to any one of (1) to (9). (11) The adhesive sheet according to (10), wherein the thickness of the adhesive layer is 5 to 25 μm. (12) The adhesive sheet according to (10), further comprising a release film. (13) A sealing body is used for sealing an object to be sealed using the adhesive sheet according to any one of (10) to (12). (14) The sealed body according to (13), wherein the object to be sealed is an organic EL element, an organic EL display element, a liquid crystal display element, or a solar cell element. [Inventive effect]

According to the present invention, it is possible to provide an adhesive composition which can be easily formed into a thin sheet and is not easily corroded to an electrode member, an organic semiconductor material, or the like when used as a sealing material; , An adhesive sheet of an adhesive layer of an organic semiconductor, or the like; and a sealed body sealed by the above-mentioned adhesive sheet.

Hereinafter, the present invention will be described in detail 1) an adhesive composition, 2) an adhesive sheet, and 3) a sealing body.

1) Adhesive composition The adhesive composition of the present invention is an adhesive composition containing the following (A) component, (B) component, and (C) component, and the adhesive is analyzed by the following air-blow capture method. In the case of a volatile component contained in the composition, the content of the volatile antioxidant is 0.2 mg / cm ³ or less in terms of toluene conversion. (A) Component: Modified polyolefin resin (B) Component: Polyfunctional epoxy compound that is liquid at 25 ° C (C) Component: Polyfunctional epoxy compound that is solid at 25 ° C

[Blow gas capture method] An adhesive layer (18 mm × 18 mm × 12 μm) formed using an adhesive composition was placed in a glass test tube, and heated in a helium stream at 120 ° C. for 20 minutes, and continuously captured by a gas trap tube. Collects gas released from the adhesive layer. Next, the trapped gas is introduced into a gas phase chromatography mass spectrometer, and a volatile component contained in the adhesive composition is analyzed. At this time, the amount of the volatile antioxidant was quantified from a calibration line made using toluene.

(A) Component: Modified polyolefin-based resin The adhesive composition of the present invention is a modified polyolefin-based resin containing the component (A). The adhesive composition of the present invention is excellent in adhesive strength by containing a modified polyolefin-based resin. In addition, by using an adhesive composition containing a modified polyolefin resin, a thin adhesive layer can be formed with high efficiency.

The modified polyolefin-based resin is obtained by performing a modification treatment on a precursory polyolefin resin using a modifying agent to obtain a functionalized polyolefin resin.

The "polyolefin resin" refers to a polymer containing a repeating unit derived from an olefin-based monomer. The polyolefin resin may be a polymer composed of only repeating units derived from an olefin-based monomer, or may be a repeating unit derived from an olefin-based monomer and a repeat derived from a monomer capable of copolymerizing with an olefin-based monomer. Unit

The olefin-based monomer is preferably an α-olefin having 2 to 8 carbon atoms, more preferably ethylene, propylene, 1-butene, isobutylene, or 1-hexene, and particularly preferably ethylene or propylene. These olefin-based monomers may be used individually by 1 type, or may use 2 or more types together. Examples of the single system capable of copolymerizing with an olefin-based monomer include vinyl acetate, (meth) acrylate, and styrene. These monomers which can be copolymerized with an olefin-based monomer may be used individually by 1 type, or may use 2 or more types together.

Examples of polyolefin resins include: Ultra Low Density Polyethylene (VLDPE), Low Density Polyethylene (LDPE), Medium Density Polyethylene (MDPE), High Density Polyethylene (HDPE), Linear Low Density Polyethylene, Polyethylene Propylene (PP), ethylene-propylene copolymer, olefin-based elastomer (TPO), ethylene-vinyl acetate copolymer (EVA), ethylene- (meth) acrylic copolymer, ethylene- (meth) acrylate copolymer Wait.

The modifier used when the polyolefin resin is modified is a compound having a functional group in the molecule. Functional groups include, for example, carboxyl, carboxylic anhydride, carboxylate, hydroxy, epoxy, amido, ammonium, nitrile, amine, amido, isocyanate, ethyl, and sulfur. Alcohol group, ether group, thioether group, sulfo group, phosphine group, nitro group, amine ester group, halogen atom and the like. Among these, a carboxyl group, a carboxylic acid anhydride group, a carboxylic acid ester group, a hydroxy group, an ammonium group, an amine group, a fluorenimine group, and an isocyanate group are more preferable, and a carboxylic acid anhydride group, an alkoxysilyl group, and a particularly preferable one Carboxylic acid anhydride group. The compound having a functional group may have two or more kinds of functional groups in the molecule.

Examples of the modified polyolefin-based resin include acid-modified polyolefin-based resin and silane-modified polyolefin-based resin. From the viewpoint of obtaining a more excellent effect of the present invention, an acid-modified polyolefin resin is preferred.

The so-called "acid-modified polyolefin resin" refers to a person who graft-modified polyolefin resin with an acid. For example, a polyolefin resin is reacted with an unsaturated carboxylic acid or an unsaturated carboxylic acid anhydride (hereinafter also referred to as "unsaturated carboxylic acid"), and a carboxyl group or a carboxylic acid anhydride group is introduced (graft modification)

Examples of unsaturated carboxylic acids that react with polyolefin resins include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaric acid, tetrahydrophthalic acid, and aconite. Unsaturated carboxylic acids such as acids; unsaturated carboxylic anhydrides such as maleic anhydride, itaconic anhydride, glutaric anhydride, citraconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, and tetrahydrophthalic anhydride. These systems can be used alone or in combination of two or more. Among these, from the viewpoint of easily obtaining an adhesive composition having more excellent adhesive strength, maleic anhydride is preferred.

The amount of unsaturated carboxylic acid or the like reacted with the polyolefin resin is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, and 0.2 to 1.0 part by mass based on 100 parts by mass of the polyolefin resin. . The adhesive composition containing the acid-modified polyolefin resin obtained in this way is more excellent in adhesive strength.

As the acid-modified polyolefin resin, a commercially available product may be used. Examples of commercially available products include: ADMER (registered trademark) (manufactured by Mitsui Chemicals), UNISOLE (registered trademark) (manufactured by Mitsui Chemicals), BondyRam (manufactured by Polyram), orevac (registered trademark) (manufactured by ARKEMA), MODIC (registered trademark) (manufactured by Mitsubishi Chemical Corporation), etc.

The so-called "silane-modified polyolefin resin" refers to a graft-modified polyolefin resin using an unsaturated silane compound. The silane-modified polyolefin resin has a structure in which a main chain polyolefin resin is graft-copolymerized with an unsaturated silane compound belonging to a side chain. For example: Silane modified polyethylene resin and silane modified ethylene-vinyl acetate copolymer, preferably: Silane modified low density polyethylene, Silane modified ultra low density polyethylene, Silane modified linear low density polymer Silane modified polyethylene resins such as ethylene.

The unsaturated silane compound that reacts with the polyolefin resin is preferably an ethylene silane compound, and examples thereof include ethylene trimethoxy silane, ethylene triethoxy silane, ethylene tripropoxy silane, and ethylene triisopropoxy Silane, ethylenetributoxysilane, ethylenetripentyloxysilane, ethylenetriphenoxysilane, ethylenetribenzyloxysilane, ethylenetrimethylenedioxysilane, ethylenetrimethylenedioxysilane, ethylenepropane Ethoxysilane, ethylene triethoxysilane, ethylene tricarboxysilane, etc. These systems can be used alone or in combination of two or more. In addition, when the unsaturated silane compound is graft-polymerized to a polyolefin resin belonging to the main chain, the conditions may be a conventional method known for 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 0.5 to 5 parts by mass based on 100 parts by mass of the polyolefin resin. When the amount of the unsaturated silane compound to be reacted is within the above range, the adhesive composition containing the obtained silane-modified polyolefin resin becomes more excellent in adhesive strength.

Commercially available silane-modified polyolefin resins can also be used. Commercially available products include, for example, LINKLON (registered trademark) (manufactured by Mitsubishi Chemical Corporation). Particularly preferred are low-density polyethylene-based LINKLON, linear low-density polyethylene-based LINKLON, ultra-low-density polyethylene-based LINKLON, and ethylene-vinyl acetate copolymer-based LINKLON.

The modified polyolefin-based resin may be used singly or in combination of two or more kinds.

The number average molecular weight (Mn) of the modified polyolefin resin is preferably 10,000 to 2,000,000, and more preferably 20,000 to 1,500,000. Tetrahydrofuran (THF) is used as the number-average molecular weight (Mn) -based solvent of the modified polyolefin resin, and gel permeation chromatography (GPC) is performed to obtain a standard polystyrene conversion value.

(B) Component: Polyfunctional epoxy compound which is liquid at 25 ° C The adhesive composition of the present invention contains a polyfunctional epoxy compound which is liquid at 25 ° C as the component (B). . The "polyfunctional epoxy compound which is liquid at 25 ° C" refers to a polyfunctional epoxy compound having a certain volume (excluding volatile components) at 25 ° C but having an indefinite shape. The viscosity at 25 ° C of the "polyfunctional epoxy compound in a liquid state at 25 ° C" used in the present invention is usually 0.1 to 100,000 mPa‧s, preferably 0.2 to 50,000 mPa‧s, and more preferably 0.3 to 10,000 mPa‧ s. Since the adhesive composition of the present invention contains the component (B), it has excellent fluidity upon heating. Therefore, by using the adhesive composition of the present invention, it is possible to form an adhesive layer with excellent unevenness tracking property with high efficiency.

The "polyfunctional epoxy compound" refers to a compound having two or more epoxy groups in the molecule.

(B) The component system includes, for example, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, hydrogenated bisphenol A epoxy resin, and hydrogenated bisphenol F epoxy resin. , Hydrogenated bisphenol S-type epoxy resin, etc. (B) The polyfunctional epoxy compound of a component may be used individually by 1 type, or may use 2 or more types together. The molecular weight of the polyfunctional epoxy compound of the component (B) is preferably 700 to 5,000, and more preferably 1,400 to 4,500. By using an adhesive composition containing the component (B) having a molecular weight of 700 or more, a lower outgassing sealing material can be easily obtained. On the other hand, since the adhesive composition containing the component (B) having a molecular weight of 5,000 or less is more excellent in fluidity, by using such an adhesive composition, an adhesive layer having more excellent unevenness tracking can be easily formed. .

The epoxy equivalent of the polyfunctional epoxy compound of the component (B) is preferably 100 g / eq or more and 500 g / eq or less, more preferably 150 g / eq or more and 300 g / eq or less. By using an adhesive composition having a polyfunctional epoxy compound (B) component having an epoxy equivalent of 100 g / eq or more and 500 g / eq or less, a sealing material with high adhesive strength and excellent hardenability can be formed with high efficiency.

(C) Component: The polyfunctional epoxy compound which is solid at 25 degreeC The adhesive composition of this invention contains the (C) component, the polyfunctional epoxy compound which is solid at 25 degreeC. The "polyfunctional epoxy compound which is solid at 25 ° C" refers to a polyfunctional epoxy resin having a softening point in a temperature range of 25 ° C or higher. Since the adhesive composition of the present invention contains the component (C), it is not easy to be in a liquid state, and it can easily maintain a certain shape, and thus it can be easily formed into a thin sheet.

(C) The component system can be exemplified by bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, hydrogenated bisphenol A epoxy resin, and hydrogenated bisphenol F epoxy resin. , Hydrogenated bisphenol S-type epoxy resin, etc. (C) The polyfunctional epoxy compound of a component can be used individually by 1 type or in combination of 2 or more types. The molecular weight of the polyfunctional epoxy compound of the component (C) is preferably 500 to 10,000, and more preferably 1,000 to 5,000.

In the adhesive composition of the present invention, the total amount of the component (B) and the component (C) is preferably 100 to 200 parts by mass, and more preferably 120 to 170 parts by mass with respect to 100 parts by mass of the component (A). When the content of the components (A) to (C) satisfies the above-mentioned requirements, the fluidity of the adhesive composition becomes moderate, and a certain shape can be easily maintained.

The content ratio (mass ratio) of (B) component and (C) component is preferably [(B) component: (C) component] = 100: 1 to 1: 1, and more preferably 10: 1 to 2: 1 . As the amount of the component (B) relative to the component (C) increases, the fluidity of the adhesive composition upon heating also increases. On the other hand, as the amount of the component (B) relative to the component (C) increases, the adhesive composition also easily maintains a certain shape.

As described later, the content of the volatile antioxidant in the adhesive composition of the present invention is extremely small. Generally, since a commercially available tackifier contains an antioxidant, the tackifier composition of the present invention preferably does not contain a tackifier. However, since an adhesive agent has the effect of improving the adhesiveness of an adhesive composition, and the effect of maintaining the shape of an adhesive composition, the adhesive composition which does not contain an adhesive agent is prone to these characteristics deterioration. Therefore, the adhesive composition of the present invention has the component (C) as an essential component. By using the component (C), an adhesive composition having more excellent adhesiveness can be obtained. In addition, by using the component (B) and the component (C) together and adjusting the ratio, the fluidity of the adhesive composition can be made moderate, so that a certain shape of the adhesive layer can be easily formed.

The adhesive composition of this invention may contain components other than said (A) component, (B) component, and (C) component. The component systems other than (A) component, (B) component, and (C) component are, for example, the following (D) component and (E) component. (D) Component: Imidazole-based hardening catalyst (E) Component: Silane coupling agent

(D) Component: Imidazole-based hardening catalysts Examples of imidazole-based hardening catalysts are 2-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2- Ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-dimethylol Imidazole and so on. Among these, 2-ethyl-4-methylimidazole is preferable. These imidazole-based hardening catalysts can be used alone or in combination of two or more.

By using an adhesive composition containing an imidazole-based hardening catalyst, a hardened material having excellent adhesiveness even at high temperatures can be easily obtained.

When the adhesive composition of the present invention contains the component (D), the content is preferably 1 to 10 parts by mass and more preferably 2 to 100 parts by mass of the total amount of the components (B) and (C). 5 parts by mass. The hardened product of the adhesive composition having an imidazole-based hardening catalyst content within this range has excellent adhesion even at high temperatures.

(E) Component: Silane coupling agent A well-known silane coupling agent can be used as a silane coupling agent. Among them, an organic silicon compound having at least one alkoxysilyl group in the molecule is preferred. Examples of the silane coupling agent system include polymerizable unsaturated silicon compounds such as ethylenetrimethoxysilane, ethylenetriethoxysilane, methacryloxypropyltrimethoxysilane, etc .; 3-glycidoxy Silicon compounds with epoxy structure, such as propyltrimethoxysilane, 8-glycidoxyoctyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane; 3 -Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -8-aminooctyltrimethoxysilane, N -(2-aminoethyl) -3-aminopropylmethyldimethoxysilane and other amine-containing silicon compounds; 3-chloropropyltrimethoxysilane; 3-isocyanatepropyltriethoxysilane , 3-mercaptopropyltrimethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride, and the like. These silane coupling agents can be used singly or in combination of two or more kinds.

By using an adhesive composition containing a silane coupling agent, a hardened product having more excellent adhesive strength under normal temperature and high temperature environments can be easily obtained.

When the adhesive composition of the present invention contains a silane coupling agent, the content thereof is preferably 0.01 to 10 parts by mass, and more preferably 0.02 to 5 parts by mass relative to 100 parts by mass of the component (A).

The adhesive composition of the present invention may contain a solvent. Examples of the solvent system include aromatic hydrocarbon solvents such as benzene and toluene; ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; n-pentane, n-hexane, and n-hexane Aliphatic hydrocarbon solvents such as heptane; alicyclic hydrocarbon solvents such as cyclopentane, cyclohexane, and methylcyclohexane. These solvents may be used alone or in combination of two or more. The content of the solvent may be appropriately determined in consideration of coating properties and the like.

The adhesive composition of the present invention may contain other ingredients within a range that does not prevent the effect of the present invention. Examples of the other components include additives such as ultraviolet absorbers, antistatic agents, light stabilizers, antioxidants, resin stabilizers, fillers, pigments, extenders, and softeners. These systems can be used alone or in combination of two or more. When the adhesive composition of the present invention contains such additives, the content can be appropriately determined according to the purpose.

The adhesive composition of the present invention can be prepared by appropriately mixing and stirring predetermined ingredients in accordance with a conventional method.

When the adhesive composition of the present invention is analyzed for the volatile components contained in the adhesive composition by the following air-blow capture method, the volatile antioxidant content is 0.2 mg / cm ³ or less in terms of toluene conversion. "Antioxidant" is an antioxidant added to suppress the oxidation of the components in the resin composition. Examples of the antioxidant system include phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and amine-based antioxidants. "Volatile antioxidants" are antioxidants that, when contained in an adhesive layer, if the adhesive layer is heated in an inert gas (helium, etc.) gas stream at 120 ° C, it will depend on the adhesive layer. Antioxidants that are volatile components released. Such a volatile antioxidant is not particularly limited, and examples thereof include a hindered phenol antioxidant.

[Blow gas capture method] An adhesive layer (18 mm × 18 mm × 12 μm) formed using an adhesive composition was placed in a glass test tube, and heated in a helium stream at 120 ° C. for 20 minutes, and continuously captured by a gas trap tube. Collects gas released from the adhesive layer. Next, the trapped gas is introduced into a gas phase chromatography mass spectrometer, and a volatile component contained in the adhesive composition is analyzed. At this time, the amount of the volatile antioxidant was quantified from a calibration line made using toluene.

In the preparation of the adhesive composition, when a commercially available product is used as the manufacturing raw material, if the commercially available product contains an antioxidant, the obtained adhesive composition contains an antioxidant. Therefore, when manufacturing the adhesive composition of the present invention, it is important to use a manufacturing material that does not contain an antioxidant at all or contains a small amount of an antioxidant. As described above, commercially available tackifiers usually contain antioxidants. Therefore, it is preferred that the tackifier composition of the present invention does not use a tackifier. Instead, by using the components (B) and (C) together, the adhesion and shape can be improved. Retention.

Since the adhesive composition of the present invention contains very little volatile antioxidant content, it is less likely to corrode electrode members, organic semiconductors, and the like when used as a sealing material. Therefore, the adhesive composition of the present invention is suitable for forming a sealing material.

2) Adhesive sheet The adhesive sheet of the present invention is an adhesive sheet having an adhesive layer, and the adhesive layer is formed using the adhesive composition of the present invention.

The thickness of the adhesive layer of the adhesive sheet is not particularly limited, but is preferably 5 to 25 μm, and more preferably 10 to 20 μm. An adhesive layer having a thickness within the above range is suitable as a sealing material.

The adhesive sheet of the present invention may be provided with a release film. The release film functions as a support during the manufacturing process of the adhesive sheet, and functions as a protective sheet for the adhesive layer until the adhesive sheet is used. When using the adhesive sheet of the present invention, the release film is usually removed by peeling.

As the release film, conventionally known materials can be used. For example, a release layer is provided on the base material for a release film, which is subjected to a release treatment with a release agent. Examples of the base material for the release film include paper base materials such as cellophane, coated paper, and high-grade paper; laminated paper on which these thermoplastic base materials are laminated with a thermoplastic resin such as polyethylene; Diesel resin, polybutylene terephthalate resin, polyethylene naphthalate resin, polypropylene resin, polyethylene resin and other plastic films. Examples of the release agent include rubber-based elastomers such as silicone resin, olefin-based resin, isoprene-based resin, and butadiene-based resin; long-chain alkyl resin, alkyd resin, and fluorine resin Wait.

When the adhesive sheet is found to have a release film, the number of release films may be one or two, and usually one (a total of two) release films are provided on each side of the adhesive layer. In this case, the two peeling films may be the same or different, but it is preferable that the two peeling films have different peeling forces. Since the peeling force of the two peeling films is different, the adhesive sheet is less prone to problems during use. That is, by setting the peeling force of the two peeling films to be different, the step of tearing the peeling film first can be performed efficiently.

The manufacturing method of an adhesive sheet is not specifically limited. For example, an adhesive sheet can be manufactured using a casting method. When an adhesive sheet is produced by a casting method, the adhesive composition of the present invention is applied to a release-treated surface of a release film by using a known method, and the obtained coating film is dried to produce an adhesive having a release film. Layer, and then by superposing another release film on the adhesive layer, an adhesive sheet can be obtained.

Examples of the method for applying the adhesive composition include a spin coating method, a spray coating method, a bar coating method, a knife coating method, a roll coating method, a doctor blade coating method, a die coating method, and a gravure coating method. The drying conditions when the coating film is dried may be, for example, a drying temperature of 80 to 150 ° C. and a drying time of 30 seconds to 5 minutes.

The adhesive layer of the adhesive sheet of the present invention is thermosetting. The conditions when the adhesive layer is thermally cured are not particularly limited. The heating temperature is usually 80 to 200 ° C, preferably 90 to 150 ° C. The heating time is usually 30 minutes to 12 hours, and preferably 1 to 6 hours.

After hardening, the adhesive strength at 23 ° C of the adhesive layer is usually 1 ~ 100N / 25mm, preferably 10 ~ 50N / 25mm, and the tear strength at 85 ℃ is usually 1 ~ 100N / 25mm. Best line 5 ~ 50N / 25mm. The peel strength at 23 ° C is tested according to JIS Z0237: 2009 at a temperature of 23 ° C, a relative humidity of 50%, and a temperature of 85 ° C (uncontrolled humidity). Measurable. The water vapor transmission rate of the adhesive layer after hardening treatment is usually 0.1 ~ 200g‧m ^-2 ‧day ^-1 , preferably 1 ~ 150g‧m ^-2 ‧day ^-1 . The water vapor transmission rate can be measured using a known water vapor transmission rate measuring device.

As described above, the adhesive layer of the adhesive sheet of the present invention does not easily corrode electrode members, organic semiconductors, and the like. Therefore, by using the adhesive sheet of the present invention, it is possible to achieve a long life of the organic EL element and the like.

3) Sealing body The object to be sealed in the sealing system of the present invention is sealed using the adhesive sheet of the present invention. The sealing system of the present invention includes, for example, a substrate, an element (an object to be sealed) formed on the substrate, and a sealing material for sealing the element. The sealing material may be, for example, an adhesive layer derived from the adhesive sheet of the present invention. (Hardened material of the adhesive layer).

The substrate is not particularly limited, and various substrate materials can be used. It is particularly preferable to use a substrate material having a high visible light transmittance. In addition, a material capable of preventing moisture and gas from penetrating from the outside of the element is preferred, and the material is excellent in solvent resistance and weather resistance. Specific examples include transparent inorganic materials such as quartz and glass; polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polystyrene, polyethylene, polypropylene, polyphenylene sulfide, Transparent plastics such as polyvinylidene fluoride, cellulose acetate, brominated phenoxy, aramide, polyimide, polystyrene, polyarylate, polyfluorene, and polyolefin; Sex film and so on. The thickness of the substrate is not particularly limited, and may be appropriately selected after considering light transmittance and blocking performance inside and outside the device.

Examples of the object to be sealed include organic EL elements, organic EL display elements, liquid crystal display elements, and solar cell elements.

The manufacturing method of the sealing body of this invention is not specifically limited. For example, after the adhesive layer of the adhesive sheet of the present invention is superimposed on an object to be sealed, heating is performed to adhere the adhesive layer of the adhesive sheet to the object to be sealed. Then, by hardening this adhesive layer, the sealing body of this invention can be manufactured.

There are no particular restrictions on the adhesion conditions when the adhesive layer of the adhesive sheet is adhered to the object to be sealed. The adhesion temperature is, for example, 23 to 100 ° C, preferably 40 to 80 ° C. This adhesion treatment may be performed while applying pressure. The hardening conditions at the time of hardening an adhesive layer are the conditions demonstrated previously.

The sealed object of the sealing system of the present invention is sealed by using the adhesive sheet of the present invention. Therefore, the sealing system of the present invention can maintain the performance of the sealed object for a long time. [Example]

Hereinafter, the present invention will be described in more detail with examples. However, the present invention is not limited in any way by the following examples. The "parts" and "%" in each case are the basis of quality without a special statement.

[Example 1] 100 parts of an acid-modified polyolefin resin (acid-modified α-olefin polymer, manufactured by Mitsui Chemicals, trade name: UNISTOLEH-200, number average molecular weight: 47,000), polyfunctional epoxy compound (1) (Hydrogenated bisphenol A epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name: YX8000, liquid at 25 ° C, epoxy equivalent: 205 g / eq), 100 parts, polyfunctional epoxy compound (2) ( Hydrogenated bisphenol A epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name: YX8040, solid at 25 ° C, epoxy equivalent: 1100g / eq, 25 parts, imidazole-based hardening catalyst (manufactured by Shikoku Chemical Co., Ltd., product Name: 1 part of Curezol 2E4MZ, 2-ethyl-4-methylimidazole), and 0.1 part of a silane coupling agent (manufactured by Shin-Etsu Chemical Industry Co., Ltd .: KBM4803), dissolved in methyl ethyl ketone to prepare a solid content concentration of 25% The adhesive composition 1. This adhesive composition 1 was coated on a release-treated surface of a release film (manufactured by Lintec, trade name: SP-PET382150), and the obtained coating film was dried at 100 ° C. for 2 minutes to form a 12 μm-thick adhesive film. The adhesive layer 1 was obtained by laminating another peeling treatment surface (made by Lintec Corporation, trade name: SP-PET381031) on the adhesive layer.

[Example 2] An adhesive composition 2 was prepared in the same manner as in Example 1 except that the amount of the polyfunctional epoxy compound (2) was changed to 50 parts in Example 1 and used. An adhesive sheet 2 was obtained.

[Example 3] Except in Example 1, instead of the polyfunctional epoxy compound (1), a polyfunctional epoxy compound (3) was used instead (hydrogenated bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation, Product name: YX8034, liquid state at 25 ° C, epoxy equivalent weight: 270 g / eq), the remainder was prepared in the same manner as in Example 1, and an adhesive composition 3 was prepared, and an adhesive sheet 3 was obtained using the same.

[Comparative Example 1] 100 parts of an acid-modified polyolefin resin- (α-olefin polymer, manufactured by Mitsui Chemicals Co., Ltd., trade name: UNISTOLEH-200, number average molecular weight: 47,000), polyfunctional epoxy compound (1 ) (Hydrogenated bisphenol A epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name: YX8000, liquid at 25 ° C) 100 parts, tackifier (styrene-based monomer, aliphatic-based monomer copolymer, softening point 95) ℃, 50 parts by Mitsui Chemicals, trade name: FTR6100), 1 part of imidazole-based hardening catalyst (manufactured by Shikoku Chemical Co., Ltd., trade name: Curezol 2E4MZ, 2-ethyl-4-methylimidazole), and silane 0.1 part of a mixture (made by Shin-Etsu Chemical Industry Co., Ltd., trade name: KBM6803) was dissolved in methyl ethyl ketone to prepare an adhesive composition 4 having a solid content concentration of 30%. An adhesive sheet 4 was obtained in the same manner as in Example 1 except that the adhesive composition 4 was used.

[Comparative Example 2] Except in Comparative Example 1, instead of the polyfunctional epoxy compound (1), a polyfunctional epoxy compound (3) was used instead (hydrogenated bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation, Product name: YX8034, liquid state at 25 ° C.), the remainder was prepared in the same manner as in Comparative Example 1 except that the adhesive composition 5 was prepared, and an adhesive sheet 5 was obtained by using the same.

For the adhesive sheets 1 to 5 obtained in Examples 1 to 3 and Comparative Examples 1 to 2, the following analysis was performed. [Outgassing analysis] Tear off a release film of the adhesive sheet obtained in the example or the comparative example, and place the adhesive sheet on the glass plate in such a manner that the exposed adhesive layer faces the glass plate, and use a heat press machine , Adhere at 23 ° C. Next, the remaining release film was torn and used as a measurement sample to generate outgassing under conditions of 120 ° C. and 20 minutes, and the amount of the generated gas was quantified. Gas chromatographic mass spectrometer (manufactured by Shimadzu Corporation, GCMS-QP2010) was used to quantify the amount of generated gas, and 5% -diphenyl-95% dimethylpolysiloxane (HP-5ms) was used for the column system. ) Implementation. At this time, a calibration curve was prepared using toluene. The amount of outgassing (the amount of outgassing (mg) per 1 cm ³ of the adhesive sheet) and the amount of volatile antioxidants (di-tert-butyl hydroxytoluene) contained therein (the amount (mg) per 1 cm ³ of the adhesive sheet) As shown in Table 1.

[Table 1]

The following items are known from Table 1. In the adhesive sheets of Examples 1 to 3, no tert-butyl hydroxytoluene was detected. On the other hand, in Comparative Examples 1 and 2, di-tert-butylhydroxytoluene was detected. Accordingly, the adhesive sheets of Examples 1 to 3 hardly contain compounds that would corrode electrode members and organic semiconductors. Therefore, the sealing materials formed by using these adhesive sheets are not likely to corrode electrode members, organic semiconductors, and the like.

no

no.

Claims (14)

An adhesive composition is an adhesive composition containing the following (A) component, (B) component, and (C) component; It is characterized by analyzing the content contained in the adhesive composition by the following air-blow capture method. In the case of volatile components, the content of volatile antioxidants is 0.2 mg / cm ³ or less in terms of toluene conversion; (A) component: modified polyolefin resin (B) component: mostly liquid at 25 ° C Functional group epoxy compound (C) component: a polyfunctional group epoxy compound which is solid at 25 ° C [blow-and-catch method] An adhesive layer (18 mm × 18 mm × 12 μm) formed using an adhesive composition is charged. In a glass test tube, it was heated at 120 ° C for 20 minutes in a helium stream, and the gas released from the adhesive layer was continuously captured by a gas trap tube. Then, the captured gas was introduced into a gas phase chromatography mass spectrometer. In this case, the volatile component contained in the adhesive composition was analyzed; at this time, the amount of the volatile antioxidant was quantified from a calibration line made using toluene. For example, the adhesive composition according to item 1 of the patent application range, wherein the component (A) is an acid-modified polyolefin resin. For example, in the adhesive composition of claim 1, the total amount of the component (B) and the component (C) is 100 to 200 parts by mass relative to 100 parts by mass of the component (A). For example, the adhesive composition according to the first patent application range, wherein the content ratio (mass ratio) of the (B) component and (C) component is [(B) component: (C) component] = 100: 1 ~ 1 :1. For example, the adhesive composition according to item 1 of the patent application scope further contains the following (D) component: (D) component: an imidazole curing catalyst. For example, the adhesive composition according to item 5 of the patent application, wherein the content of the component (D) is 1 to 10 parts by mass relative to 100 parts by mass of the total amount of the components (B) and (C). . For example, the adhesive composition according to item 1 of the patent application scope further contains the following (E) component: (E) component: a silane coupling agent. For example, the adhesive composition according to item 7 of the patent application scope, wherein the content of the component (E) is 0.01 to 10 parts by mass relative to 100 parts by mass of the component (A). For example, the adhesive composition according to item 1 of the patent application scope, wherein the volatile antioxidant is a hindered phenol antioxidant. An adhesive sheet is an adhesive sheet having an adhesive layer, wherein the adhesive layer is formed by using the adhesive composition according to any one of claims 1 to 9 of the patent application scope. For example, the adhesive sheet of the scope of application for patent No. 10, wherein the thickness of the adhesive layer is 5 to 25 μm. For example, the adhesive sheet of the scope of application for the patent No. 10, wherein a release film is further provided. The utility model relates to a sealing body, which is to be sealed by using an adhesive sheet according to any one of claims 10 to 12 of the scope of patent application. For example, the sealed body according to item 13 of the application, wherein the object to be sealed is an organic EL element, an organic EL display element, a liquid crystal display element, or a solar cell element.