Composition for encapsulation film, encapsulation film, and electronic device comprising the same

Abstract

There are provided a composition for encapsulation film, an encapsulation film, and an electronic device having the same. The present application may provide an encapsulation film having an excellent moisture barrier property, operability, workability, and durability and a structure including an element encapsulated by the encapsulation film.

Claims

1. An encapsulation film for an electronic device, including a composition comprising: a base resin having a repeating unit of Chemical Formula 1; and an additive having a compound represented by Chemical Formula 2, wherein the additive is included in an amount of 5 to 30 parts by weight with respect to 100 parts by weight of the base resin: ##STR00005## ##STR00006## where, in Chemical Formula 1 and Chemical Formula 2, each of R.sub.1 and R.sub.2 independently represents hydrogen or an alkyl group having 1 to 12 carbon atoms, n and q are 1 or more, L is a single bond or an organic linker formed of at least one selected from the group consisting of an alkylene, an arylene, an ether, an ester, a carbonyl, an allyl, an alkylallyl, an acryloyl, an alkenylene and combinations thereof, and P is a polar functional group selected from the group consisting of an acid anhydride group, an amide group, an alkoxy group, an alcohol group, an aldehyde group, a carbonyl group, a carboxyl group, an ester group, an ether group, an epoxy group, an amino group, a sulfone group, a hydroxyl group, and a maleic acid.

2. The encapsulation film for the electronic device, including the composition of claim 1, wherein the base resin is a copolymer containing 90 mol % or more of a polyisobutylene or isobutylene.

3. The encapsulation film for the electronic device, including the composition of claim 1, wherein the additive is at least one selected from the group consisting of a polyisobutenyl succinic anhydride, a polyisobutenyl amine, and a polyisobutenyl alcohol.

4. The encapsulation film for the electronic device including the composition of claim 2, wherein the base resin has a weight average molecular weight of 100,000 to 2,000,000.

5. The encapsulation film for the electronic device, including the composition of claim 1, further comprising a moisture absorbent.

6. The encapsulation film for the electronic device, including the composition of claim 5, wherein the moisture absorbent is included in an amount of 1 part by weight to 100 parts by weight with respect to 100 parts by weight of the base resin.

7. The encapsulation film for the electronic device, including the composition of claim 1, further comprising a tackifier.

8. The encapsulation film for the electronic device, including the composition of claim 1, further comprising a curable resin.

9. The encapsulation film for the electronic device, including the composition of claim 1, wherein the encapsulation film satisfies General Formula 1:
P.sub.r≧2000 gf/in  [General Formula 1] where, in General Formula 1, P.sub.r represents a peel strength of the encapsulation film with respect to glass measured at room temperature, a peel rate of 10 mm/sec, and a peel angle of 180°.

10. The encapsulation film for the electronic device, including the composition of claim 1, wherein the encapsulation film satisfies General Formula 2:
P.sub.h≧500 gf/in  [General Formula 2] where, in General Formula 2, P.sub.h represents a peel strength of the encapsulation film with respect to glass measured at a peel rate of 10 mm/sec and a peel angle of 180° after the encapsulation film is maintained under conditions at 85° C. and a relative humidity of 85% for 24 to 100 hours.

11. The encapsulation film for the electronic device, including the composition of claim 1, wherein the encapsulation film has a moisture transmittance of less than 10 g/m.sup.2.Math.day under conditions at 100° F. and a relative humidity of 100%.

12. An electronic device, comprising: an upper substrate; a lower substrate; and the encapsulation film for the electronic device, including the composition according to claim 1 provided between the upper substrate and the lower substrate and encapsulating an element.

Description

MODES OF THE INVENTION

(1) Hereinafter, the film will be described in detail with reference to examples and comparative examples, but the scope of the film is not limited to the proposed examples.

(2) Hereinafter, in the examples and comparative examples, physical properties were evaluated by the following methods.

(3) 1. Evaluation of Peel Strength

(4) A pressure sensitive adhesive film of which a pressure sensitive adhesive layer has a thickness of about 50 μm was manufactured using the pressure sensitive adhesive composition of the examples or comparative examples. The manufactured pressure sensitive adhesive film was laminated with an unreleased-PET substrate film and cut to a size having a width of one inch and a length of 20 cm. Then, a release-treated substrate film of the pressure sensitive adhesive film was released and the pressure sensitive adhesive layer was attached to a glass plate to prepare a specimen. Then, a texture analyzer was used to measure a peel strength of 180° of the specimen while releasing at a peel rate of 10 mm/sec and a peel angle of 180°.

(5) In order to evaluate adhesion reliability, a sample was left in an oven at 85° C. and a relative humidity of 85% for 100 hours, and then a change in the peel strength under high temperature and high humidity conditions was additionally observed.

(6) 2. Measurement of Water Vapor Transmission Rate

(7) The base resin used in the examples or the resin used in the comparative examples was dissolved in the solvent to prepare a resin composition. The resin composition was applied onto a substrate film (release polyester film, RS-21G, manufactured by SKC Inc.) having a thickness of 38 μm, and then dried at 110° C. for 10 minutes to manufacture a layer having a film shape and a thickness of 100 μm. The film of each composition was cross-linked according to cross-linking conditions, and then the substrate film was released. While the layer having a film shape was provided under conditions at 100° F. and a relative humidity of 100%, the water vapor transmission rate of the layer having a film shape in a thickness direction was measured. The water vapor transmission rate was measured according to a standard of ASTM F1249.

(8) 3. Evaluation of Moisture Barrier Property

(9) A size of 10 mm×10 mm (length×width) of calcium (Ca) was deposited on a glass substrate having a size of 12 mm×12 mm (length×width). Additionally, the film manufactured in the examples or comparative examples was cut to a size of 12 mm×12 mm (length×width). Then, a surface of the film was transferred to a cover glass. Then, a surface opposite to a surface to which the cover glass of the film is present was laminated on calcium of the glass substrate and heated and compressed under conditions at 50° C. and an atmosphere of 5 using an autoclave. An encapsulation layer was formed by curing at 100° C. for one hour or cured by radiation of ultraviolet at a light intensity of 2 J/cm.sup.2 according to a configuration, and a specimen was prepared. Then, the specimen was maintained in a constant temperature and humidity chamber at 85° C. and a relative humidity of 85% for about 500 hours and a length in which the calcium-deposited part is oxidized and becomes transparent was measured. Calcium has a total length of 10 mm in a direction. When a length of an oxidized part from an end of the calcium is 5 mm, calcium is completely oxidized.

(10) 4. Measurement of Transmittance

(11) The film manufactured in the exampled was cut to a size of 100 mm×100 mm and laminated using a vacuum laminator (LM-30×30-S, manufactured by NPC Inc.) at 150° C. for 10 minutes to prepare a specimen. An optical transmittance of the laminated specimen was measured using a hazemeter (NDH-5000) according to a JIS K 7105 method. As the transmittance, an optical transmittance was measured when the moisture absorbent is not added.

Example 1—Manufacture of Film

(12) 100 parts by weight of calcined dolomite was input as the moisture absorbent, and stearic acid of 0.5 parts by weight was input as the dispersant at a solid concentration of 50 wt % to toluene to prepare a moisture absorbent solution. A ball milling process was performed on the solution for 24 hours. Also, separately, 100 parts by weight of a polyisobutylene resin (Product Name: B100, Manufacturer: BASF SE) having a weight average molecular weight of 1,100,000 was input to a reactor as the base resin at room temperature and 20 parts by weight of a polyisobutenyl succinic anhydride (PIBSA) was also input. 2 parts by weight of 2-ethyl-4-methylimidazole was input as the curing agent, 10 parts by weight of trimethylolpropane triglycidyl ether was input as the thermosetting resin, 30 parts by weight of a hydrogenated dicyclopentadiene-based resin (Product Name: SU-90, Manufacturer: Kolon Industries Inc.) was input as the tackifier, and then diluted with toluene such that a solid content becomes about 20 wt %. Then, an inside of the reactor was substituted with nitrogen and the prepared solution was homogenized. The moisture absorbent solution prepared in advance was input to the homogenized solution such that a content of the calcined dolomite becomes 50 parts by weight with respect to 100 parts by weight of the base resin and mixed to prepare a composition.

(13) The prepared composition was applied onto a release surface of a release PET, dried at 110° C. for 10 minutes, and a film having a thickness of 50 μm was formed. The film was cured by heat at 100° C. for one hour as thermosetting conditions.

Example 2

(14) A film was manufactured by the same manner as in Example 1 except that the polyisobutylene resin was included in an amount of 100 parts by weight, and polyisobutenyl succinic anhydride was included in an amount of 10 parts by weight.

Example 3

(15) A film was manufactured by the same manner as in Example 1 except that 20 parts by weight of a polyisobutenyl amine was added instead of polyisobutenyl succinic anhydride.

Example 4

(16) A film was manufactured by the same manner as in Example 1 except that 1 part by weight of 1-hydroxy-cyclohexyl-phenyl ketone (BASF SE, Irgacure 184) was used as a radical initiator instead of the thermosetting agent, and 10 parts by weight of trimethylolpropane triacrylate was used as a photocurable acrylate instead of the thermosetting resin. Photocuring of the film was performed by radiating ultraviolet at a light intensity of 2 J/cm.sup.2.

(17) TABLE-US-00001 TABLE 1 Example 1 Example 2 Example 3 Example 4 Base resin B100 B100 B100 B100 Polar additive PIBSA PIBSA PIBA PIBSA Tackifier SU-90 SU-90 SU-90 SU-90 Curing 2E4MZ 2E4MZ 2E4MZ HCPK agent/initiator Thermosetting/ TMPTGE TMPTGE TMPTGE TMPTA photocurable resin Moisture calcined calcined calcined calcined absorbent dolomite dolomite dolomite dolomite B100: Polyisobutylene resin PIBSA: Polyisobutenyl succinic anhydride PIBA: Polyisobutenyl amine SU-90: Hydrogenated dicyclopentadiene-based resin 2E4MZ: 2-Ethyl-4-methylimidazole HCPK: 1-Hydroxy-cyclohexyl-phenyl ketone TMPTGE: Trimethylolpropane triglycidyl ether TMPTA: Trimethylolpropane triacrylate

Comparative Example 1

(18) A film was manufactured by the same manner as in Example 1 except that 100 parts by weight of the polyisobutylene resin was used without a polyisobutenyl succinic anhydride.

Comparative Example 2

(19) 100 parts by weight of a silane-modified epoxy resin (KSR-177, Kukdo Chemical Co., Ltd.) and 60 parts by weight of a phenoxy resin (YP-50, Dong Do Tech Co., Ltd.) were input to a reactor at room temperature and diluted with methylethylketone. 10 parts by weight of 2-ethyl-4-methylimidazole (Shikoku Chemicals Corp.) serving as a curing agent was input to the homogenized solution, and was stirred at a high speed for one hour. The moisture absorbent solution prepared in advance was input to the homogenized solution such that a content of the calcined dolomite was 50 parts by weight with respect to 100 parts by weight of the silane-modified epoxy resin and mixed to prepare a composition.

(20) The prepared composition was applied onto a release surface of a release PET and dried at 110° C. for 10 minutes to form a film having a thickness of 50 μm. The film was cured at 100° C. for 3 hours as thermosetting conditions.

Comparative Example 3

(21) A film was manufactured by the same manner as in Example 1 except that 10 parts by weight of a polyester acrylate adhesion promoter (Sartomer Arkema Group, CN704) were added instead of the polyisobutenyl succinic anhydride.

(22) TABLE-US-00002 TABLE 2 Comparative Comparative Comparative Example 1 Example 2 Example 3 Base resin B100 YP-50 B100 Polar additive — — PEA Tackifier SU-90 — SU-90 Curing 2E4MZ 2E4MZ 2E4MZ agent/initiator Thermosetting/ TMPTGE KSR-177 TMPTGE photocurable resin Moisture calcined calcined calcined absorbent dolomite dolomite dolomite B100: Polyisobutylene resin YP-50: Phenoxy resin PEA: Polyester acrylate SU-90: Hydrogenated dicyclopentadiene-based resin 2E4MZ: 2-Ethyl-4-methylimidazole TMPTGE: Trimethylolpropane triglycidyl ether KSR-177: Epoxy resin

(23) TABLE-US-00003 TABLE 3 Adhe- Adhe- Water vapor sion sion transmission Moisture Trans- (gf/in), (gf/in), rate barrier mittance 0 hr 100 hr (g/m.sup.2 .Math. day) property* (%) Example 1 2200 1600 3 1 93 2 2000 1300 4 1 94 3 2100 1500 3 1 92 4 2000 1400 3 2 94 Compar- 1 1400 400 3 3 — ative 2 2500 300 12 4 — Example 3 1500 300 7 3 — *a length oxidized from a surface of calcium in a direction (unit: mm)

(24) As can be seen in the evaluation of physical properties, the films of Examples 1 to 4 have excellent adhesion at room temperature, excellent adhesion under high temperature and high humidity conditions, a small water vapor transmission rate and exhibit an excellent property in moisture permeability. However, it can be seen that, since the polyisobutenyl succinic anhydride is not provided in Comparative Example 1, adhesion and adhesion reliability under high temperature and high humidity conditions are not provided to the extent of the examples. Also, it can be seen that Comparative Example 2, in which the polyisobutylene base resin is not used, has insufficient high temperature and high humidity adhesion compared to when the polyisobutylene base resin is used. In Comparative Example 3, it can be seen that optical transmittance and adhesion decrease since compatibility of the adhesion promoting additive with the polyisobutylene base resin is insufficient. When a polyisobutenyl resin modified with succinic anhydride is included, compatibility with the polyisobutylene resin serving as a base resin is excellent, transparency is not degraded, interfacial adhesion increases due to a polar functional group, and reliability under high temperature and high humidity conditions increases.