KR20170109826A - Thermosetting adhesive flim - Google Patents

Abstract

The present invention relates to an epoxy resin composition comprising 15 to 25 parts by weight of a first epoxy resin having an epoxy equivalent of 100 to 1000 g / eq, 10 to 35 parts by weight of a second epoxy resin having an epoxy equivalent of 5000 to 15000 g / eq and a molecular weight of 20,000 to 100,000, 0.01 to 2 parts by weight of a core-shell type curing agent comprising a core containing a basic compound and a shell containing a third epoxy resin, 20 to 60 parts by weight of a ketone-based compound solvent and 10 to 25 parts by weight of a hygroscopic agent, The content of the thermosetting adhesive composition is 100 ppm or less, and the adhesive film formed by drying the composition.
The adhesive film according to the present invention can effectively encapsulate the organic EL device to provide excellent physical properties to the product and have storage stability at room temperature.

Description

[0001] Thermosetting adhesive flim [0002]

The present invention relates to a thermosetting adhesive film.

An organic electronic device (OED) is a device including a functional organic material. Examples of the organic electronic device or the organic electronic device included in the organic electronic device include a photovoltaic device, a rectifier, a transmitter and an organic light emitting diode (OLED) Can be illustrated.

Of these, organic EL devices are generally vulnerable to external factors such as moisture. For example, an organic EL device usually includes a layer of a functional organic material existing between a pair of electrodes including a metal or a metal oxide, There is a problem such as peeling due to the influence of moisture at the interface, oxidation of the electrode due to moisture, increase of the resistance value, or deterioration of the organic material itself, resulting in loss of light emitting function or lowering of luminance.

BACKGROUND ART [0002] Recently, a widely used method for cutting off water and oxygen in an organic light emitting device is a method in which a light emitting layer is deposited on a glass (or polymer film) substrate in a predetermined form and the light emitting layer is formed on a glass can (or metal can) And curing with a UV curable adhesive. However, such a method is very effective in a small area, but when applied to a large area, it is very difficult to obtain impact resistance and workability.

To solve this problem, Patent Document 1 specifies the amount of chlorine (Cl) in a polymer film, but the application of a cyacrylic epoxy resin and a thermal initiator does not satisfy the barrier property under high temperature and high humidity of the cured product.

In Patent Document 2, a composition comprising an olefin resin containing carbon and hydrogen as a main component and an epoxy thermosetting resin material is insufficient in adhesiveness and adhesion durability.

Further, in accordance with the demand of the organic electronic device, a thermosetting adhesive film is also required to be mass-produced, and accordingly, there is a need to keep storage stability in mind.

Korean Patent Laid-Open Publication No. 2012-0154783 Japanese Patent Laid-Open No. 2008-059868

It is a technical object of the present invention to provide a thermosetting adhesive film to meet such a demand.

According to an aspect of the present invention,

15 to 25 parts by weight of a first epoxy resin having an epoxy equivalent of 100 to 1000 g / eq;

10 to 35 parts by weight of a second epoxy resin having an epoxy equivalent of 5000 to 15000 g / eq and a molecular weight of 20,000 to 100,000;

0.01 to 2 parts by weight of a core-shell type curing agent comprising a core containing an amine-based compound and a shell containing a third epoxy resin;

20 to 60 parts by weight of a ketone-based compound solvent; And

And 10 to 25 parts by weight of a moisture absorbent, wherein the content of Cl is 100 ppm or less. The adhesive composition is dried to provide an adhesive film.

As described above, the adhesive composition according to the present invention and the adhesive film formed by drying the composition effectively encapsulate the organic EL device, can provide excellent physical properties to the product, and can have excellent storage stability at room temperature.

1 is a graph showing changes in viscosity with time at 40 ° C of Examples and Comparative Examples of the present invention.

The thermosetting adhesive composition used in the organic EL device according to one embodiment of the present invention may include the following constitution.

15 to 25 parts by weight of a first epoxy resin having an epoxy equivalent of 100 to 1000 g / eq, 10 to 35 parts by weight of a second epoxy resin having an epoxy equivalent of 5000 to 15000 g / eq and a molecular weight of 20,000 to 100,000, 0.01 to 2 parts by weight of a core-shell type curing agent containing a core comprising a core and a third epoxy resin, 20 to 60 parts by weight of a ketone-based compound solvent and 10 to 25 parts by weight of a moisture absorbent, 100 ppm or less.

The adhesive composition according to the present invention and the adhesive film formed by drying the adhesive composition can maintain the film or the shape of the adhesive even in the uncured state. Therefore, physical or chemical damage to the device is prevented during encapsulation or encapsulation of the organic EL device using the adhesive, and the process can proceed smoothly.

In addition, it is possible to prevent bubbles from being mixed in the encapsulation or encapsulation process of the organic EL element, and the lifetime of the device to be reduced. The upper limit of the viscosity of the thermosetting adhesive composition can be controlled within a range of about 10 ⁹ poises or less in consideration of, for example, processability.

Also, the adhesive film formed by drying the thermosetting adhesive composition may have a water vapor transmission rate (WVTR) of less than 20 g / m ² * day at 38 ° C and 100% relative humidity. The moisture transmittance is, for example, the moisture transmittance of the thermosetting adhesive film with respect to the thickness direction measured with a film-like layer having a thickness of 80 占 퐉 positioned at a relative humidity of 38 占 폚 and 100%. The moisture permeability can be measured according to the provisions of ASTM F1249-13.

The first epoxy resin used as the curable adhesive resin may include at least one selected from the group consisting of an alicyclic epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and an epoxidized polybutadiene resin . The first epoxy resin is a resin which can be cured to exhibit adhesiveness. By controlling the amount of the curing agent, the cross-linking agent, or the initiator used so that the curable adhesive film has the moisture permeability as described above, the crosslinking structure or density of the curable resin Can be adjusted. If the curable adhesive resin has a moisture permeability as described above, it is possible to effectively prevent moisture, moisture, oxygen, and the like from penetrating into the organic EL element encapsulation structure. The lower the numerical value of the moisture permeability of the curable adhesive resin, the better the performance of the sealing structure. The lower limit of the moisture permeability is not particularly limited.

The first epoxy resin according to an embodiment of the present invention may have an epoxy equivalent of 100 to 1000 g / eq and a viscosity of 1000 to 10,000 cps. The properties such as the adhesion performance of the cured product and the glass transition temperature can be maintained within an appropriate range in the range of the epoxy equivalent.

The first epoxy resin according to an embodiment of the present invention may be contained in the adhesive composition in an amount of 15 to 25 parts by weight, and if it is less than 15 parts by weight, the adhesive strength and the adhesive strength after curing are lowered at room temperature. The moldability of the adhesive film may be deteriorated.

The adhesive film according to an embodiment of the present invention may include a second epoxy resin as a binder resin. The binder resin may serve to improve the formability when the adhesive composition is molded into a film or a sheet.

The second epoxy resin may include a phenoxy resin synthesized from bisphenol A type and bisphenol F type in order to have compatibility with other components such as a curable adhesive resin.

The second epoxy resin has a high molecular weight, for example, an epoxy equivalent of 5000 to 15000 g / eq, a molecular weight (Mw) of 20,000 to 100,000, and a Tg value of 50 to 120 ° C.

When the second epoxy resin is contained as the binder resin, it may be contained in an amount of 10 to 35 parts by weight in the thermosetting adhesive composition. If the second epoxy resin is less than 10 parts by weight, the coating film may not be formed on the adhesive film formed by drying the adhesive composition. If the second epoxy resin is more than 35 parts by weight, the flexibility of the adhesive film may be significantly reduced.

The moisture absorbing agent may include at least one selected from the group consisting of metal oxides, zeolites, and molecular sieves such as silica gel and activated carbon. The metal oxide may include calcium oxide (CaO).

The shape of the hygroscopic agent is not particularly limited, and may be, for example, a shape such as a sphere, an ellipse, a polygon, or an amorphous shape. Further, the moisture absorbent may have an average particle diameter of, for example, from about 0.25 m to about 25 m. It is possible to block or remove moisture in the range of the above-mentioned particle size, and the sealing process can proceed smoothly, and the sealing process or the organic electronic device may not be damaged afterwards.

If the amount of the moisture absorber is less than 10 parts by weight, the moisture barrier property may be lowered and the moisture permeability may be increased. If the amount of the moisture absorber is more than 25 parts by weight, the thermosetting adhesive The adhesion of the film may be significantly reduced.

The moisture absorbent may be incorporated into the composition after appropriate processing. For example, the moisture absorbent may be applied to the milling process to adjust the particle size before compounding the moisture absorber in the adhesive composition. In order to crush the moisture absorbent, for example, a three roll mill, a bead mill or a ball mill may be used.

The thermosetting adhesive composition according to one embodiment of the present invention does not further include a filler. The filler in the related art can be extended by increasing the path of moisture or moisture penetrating into the sealing structure by using, for example, an inorganic filler to suppress the penetration thereof. However, the thermosetting adhesive film according to the present invention By including the first epoxy resin and the second epoxy resin in combination with the ratio of the above-described moisture absorber, the moisture absorber can be substituted for the function without the need for a separate filler.

The adhesive composition may also contain a curing agent capable of reacting with the curable adhesive resin to form a crosslinked structure or the like, depending on the kind of the curable adhesive resin.

As the curing agent according to an embodiment of the present invention, a suitable kind may be selected and used depending on the kind of the curable adhesive resin or the functional group contained in the resin. In particular, the composition contains 0.01 to 2 parts by weight of a core-shell type curing agent containing a core containing an amine compound and a shell containing a third epoxy resin, wherein the amine-based compound of the core-shell type curing agent is an amine- As a hardener

The amine adduct type curing agent is obtained by the reaction of a third epoxy resin and an amine compound.

Examples of the amine compound include amine compounds such as methylamine, ethylamine, propylamine, butylamine, ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, ethanolamine, propanolamine, cyclohexylamine , Primary amines having no tertiary amino group such as isophoronediamine, aniline, toluidine, diaminodiphenylmethane, and diaminodiphenylsulfone; But are not limited to, dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, dimethanolamine, diethanolamine, dipropanolamine, dicyclohexylamine, piperidine, piperidone, diphenylamine Secondary amines having no tertiary amino group, such as phenylmethylamine and phenylethylamine; And the like. These may be used singly or in combination of two or more.

In the compound having at least one tertiary amino group and at least one active hydrogen group, examples of the active hydrogen group include a primary amino group, a secondary amino group, a hydroxyl group, a thiol group, a carboxylic acid, and a hydrazide group .

Examples of the compound having at least one tertiary amino group and at least one active hydrogen group include 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl-2-dimethylaminoethanol, Aminoalcohols such as aminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, methyldiethanolamine, triethanolamine and N -? - hydroxyethylmorpholine; Aminophenols such as 2- (dimethylaminomethyl) phenol and 2,4,6-tris (dimethylaminomethyl) phenol; Methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, Methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-ethyl-4-methylimidazole Methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4- Imidazoles;

1- (2-hydroxy-3-phenoxypropyl) -2- phenylimidazoline, 1- (2-hydroxy-3-butoxypropyl) -2- methylimidazoline, 2- Ethylimidazoline, 2-ethylimidazoline, 2-benzimidazoline, 2-phenylimidazoline, 2- (o-tolyl) Imidazoline, tetramethylene-bis-imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-imidazoline, 1,3,3-trimethyl-1,4-tetramethylene- bis Imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-4-methylimidazoline, 1,3,3-trimethyl-1,4-tetramethylene- Bis-imidazoline, 1,4-phenylene-bis-imidazoline, 1,4-phenylene-bis Imidazolines such as 4-methylimidazoline; But are not limited to, dimethylaminopropylamine, diethylaminopropylamine, dipropylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, N-methylpiperazine Tertiary amino amines such as N-aminoethylpiperazine, diethylaminoethylpiperazine and the like; Aminomercaptans such as 2-dimethylaminoethanethiol, 2-mercaptobenzoimidazole, 2-mercaptobenzothiazole, 2-mercaptopyridine, and 4-mercaptopyridine; Aminocarboxylic acids such as N, N-dimethylaminobenzoic acid, N, N-dimethylglycine, nicotinic acid, isonicotinic acid, picolinic acid; N, N-dimethylglycine hydrazide, nicotinic acid hydrazide, isonicotinic acid hydrazide, and the like.

By using the core-shell type curing agent, the structure of the third epoxy resin contained in the shell is not deformed at room temperature, so that the amine compound contained in the core is not exposed in the thermosetting adhesive film, So that the storage stability of the thermosetting adhesive film can be secured. Particularly, in the case of the third epoxy resin, from the viewpoints of suppressing the interfacial stress between the layers after curing due to adhesion, curing shrinkage or difference in curing speed, etc., it is preferable to use a thermosetting resin (first epoxy resin) , And the third epoxy resin may include at least one selected from the group consisting of a bisphenol A type epoxy resin having an epoxy equivalent of 150 to 300 g / eq and a bisphenol F type epoxy resin.

The core-shell type curing agent may have a viscosity of 70,000 to 200,000 cps and a curable temperature of 80 to 110 ° C. If the amount of the core-shell type curing agent is less than 0.01 part by weight, the amount of the core-shell type curing agent may be too small to be cured. If the amount is more than 2 parts by weight, shrinkage of the coating film may occur.

In one example, the curing agent may include 1 to 10 parts by weight of a curing agent containing a phenolic compound in the composition. The phenolic compound may be phenol novolak. When the phenolic compound is contained in less than 1 part by weight in the thermosetting adhesive composition, the bonding strength may be lowered at high temperature and high humidity. If the phenolic compound is more than 10 parts by weight, Can be difficult.

The bonding composition according to one embodiment of the present invention may further contain a plasticizer; Additives such as ultraviolet stabilizers and / or antioxidants.

According to an embodiment of the present invention, the adhesive composition may be prepared by using an epoxy resin having a chlorine content of 100 ppm or less so that the total amount of chlorine in the finally prepared adhesive composition is 100 ppm or less. When applied to encapsulate an organic EL device, The occurrence of deterioration can be prevented in advance.

The solvent is not particularly limited. However, when the drying time of the solvent is excessively long or when it is necessary to dry at a high temperature, a problem may arise in terms of workability or durability of the adhesive film, and therefore a solvent having a volatilization temperature of 100 ° C or less may be used. In consideration of film formability and the like, a small amount of a ketone-based compound solvent having a volatilization temperature in the above range can be mixed and used. Examples of the solvent include, but are not limited to, methyl ethyl ketone (MEK), acetone, and the like.

The adhesive film of the present invention may be one in which the adhesive composition is dried to remove the solvent and have a film shape. The adhesive layer may have an adhesive layer including the above-described respective members, and the adhesive layer may also be in the form of a film or a sheet. Such an adhesive layer can be used for encapsulating the organic EL device.

The adhesive film may further include a base film or a release film (hereinafter may be referred to as " first film "), and the adhesive layer may have a structure formed on the base material or the release film . The structure may further include a substrate or a release film (hereinafter sometimes referred to as " second film ") formed on the adhesive layer.

The adhesive film may have a structure including only the film or sheet adhesive film which retains the solid or semisolid state at room temperature by having the adhesive composition without a supporting substrate such as a substrate or a release film, And a structure in which an adhesive film is formed on both sides of the film.

The adhesive film includes a curable adhesive resin which is solid or semi-solid at room temperature, and therefore may also be solid or semi-solid at room temperature. The curable adhesive resin contained in the adhesive film which is solid or semi-solid can be in an uncured state. Such an adhesive resin can be cured in a sealing structure of an organic EL element to be described later to form a crosslinked structure.

The thickness of the adhesive film is not particularly limited and may be suitably selected in consideration of the use. For example, the adhesive layer may have a thickness of about 10 m to 100 m and a thickness of 10 to 50 m. The thickness of the adhesive film can be adjusted, for example, in consideration of the filling property, the processability, and the economical efficiency when the sealing material is used as an encapsulating material for an organic EL device.

In one example, the method may comprise applying the coating solution comprising the adhesive composition in a sheet or film form onto a substrate or release film, and drying the applied coating solution. The method of manufacture may also include adhering an additional substrate or release film onto the dried coating solution.

The coating liquid containing the adhesive composition can be prepared, for example, by dissolving or dispersing the components of each adhesive composition described above in an appropriate solvent. In one example, the adhesive composition may be prepared in such a manner that it includes dissolving or dispersing in the moisture absorber or solvent, and pulverizing and then mixing the pulverized moisture absorber with the curable adhesive resin. The ratio of the hygroscopic agent and the curable adhesive resin in the above process can be controlled within the above-described range, for example, depending on the desired moisture barrier property and film formability.

The solvent used for preparing the coating liquid is not particularly limited. However, when the drying time of the solvent is excessively long or when it is necessary to dry at a high temperature, a problem may arise in terms of workability or durability of the adhesive film, and therefore a solvent having a volatilization temperature of 100 ° C or less may be used. In consideration of film formability and the like, a small amount of a ketone-based compound solvent having a volatilization temperature in the above range can be mixed and used. Examples of the solvent include, but are not limited to, methyl ethyl ketone (MEK), acetone, and the like.

The method of applying the coating solution to the base material or the release film is not particularly limited and a known coating method such as knife coat, roll coat, spray coat, gravure coat, curtain coat, comma coat or lip coat can be applied .

The applied coating liquid may be dried to volatilize the solvent and form an adhesive layer. The drying can be carried out, for example, at a temperature of 70 ° C to 150 ° C for 1 minute to 10 minutes. The conditions of the drying may be changed in consideration of the kind and ratio of the solvent used or the possibility of curing of the curable adhesive resin.

Hereinafter, the present invention will be described in more detail based on the following examples, but the present invention is not limited to these examples.

Example  1-7 and Comparative Example  1-7

Using the ingredients and contents shown in Tables 1 and 2 below, the compositions were prepared as follows.

(A): Epoxy resin having a Cl content of 1000 ppm or less

   - Mitsubishi YL980 (epoxy equivalent 185 g / eq)

   - Mitsubishi Corp. YX4000H (epoxy equivalent 194 g / eq)

   - Daicel chemical company Celloxide 2021P

   - Nippon soda JP-100 (epoxy equivalent 200 g / eq)

(A-1) Component: Epoxy resin having a Cl content of 3000 ppm

    - Mitsubishi JER 828 (epoxy equivalent 186 g / eq)

Component (B): phenoxy resin

    - Mitsubishi JER 4275 (epoxy equivalent: 9,000 g / eq, weight average molecular weight: 60,000)

(B-1) Component: Acrylic binder

- P3-TEA (weight average molecular weight: 800,000)

(C) Component: Core-shell type curing agent

(Novacure HX3921HP Asahi Kasei Materials Co., Ltd.) containing 30 wt% of an amine curing agent in the core in an epoxy resin (a mixture of a bisphenol A epoxy resin and a bisphenol F epoxy resin)

 (C-1) Component:

2-ethyl 4-methylimidazole (2E4MZ manufactured by Shikoku Seiko Kogyo Co., Ltd.)

② P0505 manufactured by Shikoku Seiko Co., Ltd.

(3) Non-core-shell type amine adduct Latent curing agent (Ajicure PN-23 manufactured by Ajinomoto Fine Tech Co., Ltd.)

 (D) Adsorbent: CaO (UBE Material Co.)

Constituent Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 (A) Component Celloxide 2021P 45 YL980 45 30 40 40 30 JP-100 15 10 YX4000H 5 45 (A-1) Component JER828 Component (B) JER4275 35 35 35 32 32 30 30 (B-1) Component P3-TEA (C) Component HX3921HP 5 5 5 8 8 10 10 (C-1) Component 2E4MZ P0505 PN-23 (D) Component CaO 15 15 15 15 15 20 20

Constituent Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 (A) Celloxide 2021P YL980 45 45 45 45 JP-100 YX4000H (A-1) JER828 35 45 45 (B) JER4275 35 35 35 35 (B-1) P3-TEA 35 35 35 (C) HX3921HP 5 5 (C-1) 2E4MZ 5 5 P0505 5 PN-23 5 5 (D) CaO 15 15 15 15 15 15 15

Test Example

[Test Methods]

[Production of Film]

The curable resin composition prepared above was uniformly coated on a mold-treated PET surface (thickness of 38 mu m) by a die coater so that the thickness of the resin composition layer after drying was 30 mu m, dried at 100 DEG C for 5 minutes, Thereby forming a curable adhesive film.

[Production of organic EL device]

ITO sputtering (ITO thickness: 150 nm, sheet resistance: < 14 Ω / m ² ) was performed on the glass substrate to produce a transparent electrode glass substrate. ITO was patterned by photolithography to form an ITO electrode pattern.

A metal electrode layer (100 nm) and an organic EL layer (50 nm) were sequentially deposited on the patterned ITO electrode.

Finally, a rear electrode (200 [mu] m) was deposited to fabricate an organic EL device.

After the adhesive film was vacuum-bonded under the autoclave condition, the adhesive film obtained in Example 1-7 and Comparative Example 1-7 was cured to prepare an organic EL device, and the following experiment was conducted. The results are shown in Tables 3 and 4.

 [Check for Dark Spot]

A DC voltage of about 5 V was applied to the organic EL device manufactured in an atmosphere of 60 DEG C and 90% RH, and after 500 hours passed, the emission state of the organic EL was observed to confirm whether a dark spot occurred.

Judgment Criteria

○: No increase in driving voltage

 Δ: Driving voltage rise Less than 10%

×: Driving voltage rise 10% or more.

[Storage stability]

The prepared adhesive film was measured for initial viscosity using a rheometer (Vo).

The adhesive film was kept frozen and the viscosity of the adhesive film was measured (V) over time. The rate of change (%) was measured by the following equation and the month with a rate of change of 20% or more was confirmed.

The storage stability was judged to be good for more than 6 months, NG for less than 1 month to 6 months, NG for less than 1 month.

(formula)

Change rate (%) = (V-Vo) / Vo x 100

[Calcium test]

The adhesive film (80 mm x 80 mm) prepared in Example was vacuum-bonded to an organic substrate (100 mm x 100 mm) deposited with calcium, and then a metal substrate was bonded.

The prepared specimen was cured at 100 占 폚, left under a condition of 85 占 폚 and 85% RH, and moisture permeated with time and the length of transparency was measured.

[Water permeability]:

After the film was thermally cured at 100 ° C for 3 hours, a MOCON test was performed on a film having a thickness of 100 μm at a temperature of 38 ° C., a relative humidity of 100%, and a pressure of 760 mmHg using a carrier gas with nitrogen gas.

[Determination of chlorine content]

The chlorine content of the resin composition was measured as follows. Approximately 30 mg of sample and 10 mL of hydrogen peroxide solution (concentration 0.5%) were weighed and fired in a combustion flask, shaken, and ultrapure water was added to make 100 mL. Thereafter, the amount of chlorine was measured by quantitative analysis of chlorine using an ion chromatograph analyzer.

○: not more than 100 ppm

×: not more than 100 ppm

[Adhesive strength]

The 30 탆 thick film thus prepared was laminated on a 5 mm x 5 mm glass substrate, cured at 100 캜 for 3 hours, and then measured for die shear strength with DAGE 4000 (DAGE 90).

[Curing rate]

The curing rate was calculated by measuring the calorific value (Ho) before curing and the calorific value (H) after curing with a differential scanning calorimeter (DSC).

[Evaluation of storage stability according to temperature and time]

The rate of change in viscosity with time at a storage temperature of 40 ° C is shown in Fig.

Measurement method / unit Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Chlorine content ○ ○ ○ ○ ○ ○ ○ Storage stability ○ ○ ○ ○ ○ ○ ○ Adhesive strength Kgf 6.5 5.0 7.5 1.0 9.0 6.2 4.5 Hardening rate % 99 99 90 99 80 99 99 Moisture permeability g / m ² * day 7 8 10 9 20 7 8 Calcium test mm 4 4 4 6 5 4 4 Check for Dark Spot ○ ○ ○ ○ ○ ○ ○

Measurement method / unit Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Chlorine content X ○ ○ ○ ○ X X Storage stability ○ X X X ○ X X Adhesive strength kgf 6.2 6.4 6.1 6.3 7.8 8.2 8.0 Hardening rate % 99 99 99 99 99 99 99 Moisture permeability g / m ² * day 7 7 9 8 35 40 38 Calcium test mm 4 4 4 4 7 7 7 Check for Dark Spot X ○ ○ ○ X X X

The adhesive film according to an embodiment of the present invention has adhesiveness, low moisture permeability, storage stability, and does not deteriorate the organic EL element. Therefore, the present invention can be suitably used for use in display parts such as organic EL.

Claims (11)

15 to 25 parts by weight of a first epoxy resin having an epoxy equivalent of 100 to 1000 g / eq;
10 to 35 parts by weight of a second epoxy resin having an epoxy equivalent of 5000 to 15000 g / eq and a molecular weight of 20,000 to 100,000;
0.01 to 2 parts by weight of a core-shell type curing agent comprising a core containing an amine-based compound and a shell containing a third epoxy resin;
20 to 60 parts by weight of a ketone-based compound solvent; And
And 10 to 25 parts by weight of a moisture absorbent,
Wherein the content of Cl is 100 ppm or less. The method according to claim 1,
Wherein the first epoxy resin comprises at least one member selected from the group consisting of an alicyclic epoxy resin, a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and an epoxidized polybutadiene resin. The method according to claim 1,
Wherein the second epoxy resin comprises a phenoxy resin synthesized from bisphenol A and bisphenol F. The method according to claim 1,
Wherein the third epoxy resin comprises at least one selected from the group consisting of a bisphenol A type epoxy resin having an epoxy equivalent of 150 to 300 g / eq and a bisphenol F type epoxy resin. The method according to claim 1,
Wherein the moisture absorbent comprises at least one selected from the group consisting of a metal oxide and zeolite, silica gel and activated carbon as molecular sieve. The method according to claim 1,
Wherein the moisture absorbent comprises CaO. The method according to claim 1,
Wherein the adhesive composition further comprises 1 to 10 parts by weight of a curing agent containing a phenolic compound. A thermosetting adhesive film having a film shape by drying the adhesive composition of claim 1. The method of claim 8,
Wherein the adhesive film has a water vapor transmission rate at a water vapor transmission rate (WVTR) of less than 10 g / m ² * day at 38 ° C and 100% relative humidity. The method of claim 8,
Wherein the adhesive film is interposed between the substrate on which the organic EL layer is formed and the protective substrate and is attached to the entire surface with an adhesive on a curing film at 70 to 100 占 폚. A method for producing a thermosetting adhesive film, comprising applying the composition of claim 1 to a release film and drying to obtain a film shape.

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