Pressure-sensitive adhesive composition, pressure-sensitive adhesive film, and method of manufacturing organic electronic device using the same

Abstract

Provided are a pressure-sensitive adhesive composition, a pressure-sensitive adhesive film, and a method of manufacturing an organic electronic device using the same. The pressure-sensitive adhesive composition that may effectively block moisture or oxygen penetrated into an organic electronic device from an external environment, and exhibit reliability under harsh conditions such as high temperature and high humidity and excellent optical characteristics, and a pressure-sensitive adhesive film including the same are provided.

Claims

1. A pressure-sensitive adhesive composition, comprising: an encapsulating resin which is a copolymer of a diene and an olefin-based compound having one carbon-carbon double bond, wherein the encapsulating resin has a weight average molecular weight (Mw) of 100,000 to 2,000,000; a tackifier; a multifunctional active energy ray-polymerizable compound which is included at 5 to 18 parts by weight relative to 100 parts by weight of the encapsulating resin; and a silane compound satisfying Formula 1, wherein the pressure-sensitive adhesive composition has a gel content represented by Equation 1 of 50% or more, and wherein the multifunctional active energy ray-polymerizable compound forms a crosslinking structure with the silane compound satisfying Formula 1, and the crosslinking structure forms a semi-interpenetrating polymer network with the encapsulating resin: ##STR00003## wherein R.sub.1 is hydrogen or an alkyl group, R.sub.2 and R.sub.3 are each independently hydrogen, or a linear, branched, or cyclic alkyl group, or R.sub.2 is linked with R.sub.3, thereby forming a cyclic alkyl group, R.sub.4, R.sub.5, and R.sub.6 are each independently hydrogen, an alkyl group, or an alkoxy group, at least one of R.sub.4, R.sub.5, and R.sub.6 is an alkoxy group, and n is an integer of 1 or more,
Gel content (%)=B/A100[Equation 1] wherein A is a mass of the pressure-sensitive adhesive composition, and B is a dry mass of an insoluble content of the pressure-sensitive adhesive composition remaining after being dipped in toluene at 60 C. for 24 hours and filtered through a 200-mesh filter (pore size of 200 m).

2. A pressure-sensitive adhesive composition, comprising: an encapsulating resin which is a copolymer of a diene and an olefin-based compound having one carbon-carbon double bond, wherein the encapsulating resin has a weight average molecular weight (Mw) of 100,000 to 2,000,000; a tackifier; a multifunctional active energy ray-polymerizable compound which is included at 5 to 18 parts by weight relative to 100 parts by weight of the encapsulating resin; and a silane compound satisfying Formula 1, wherein the pressure-sensitive adhesive composition has a gel content represented by Equation 1 of 50% or more, and wherein the active energy ray-polymerizable compound forms a crosslinking structure with the silane compound satisfying Formula 1, and the encapsulating resin forms a crosslinking structure with the active energy ray-polymerizable compound or the silane compound satisfying Formula 1, thereby forming an interpenetrating polymer network: ##STR00004## wherein R.sub.1 is hydrogen or an alkyl group, R.sub.2 and R.sub.3 are each independently hydrogen, or a linear, branched, or cyclic alkyl group, or R.sub.2 is linked with R.sub.3, thereby forming a cyclic alkyl group, R.sub.4, R.sub.5, and R.sub.6 are each independently hydrogen, an alkyl group, or an alkoxy group, at least one of R.sub.4, R.sub.5, and R.sub.6 is an alkoxy group, and n is an integer of 1 or more,
Gel content (%)=B/A100[Equation 1] wherein A is a mass of the pressure-sensitive adhesive composition, and B is a dry mass of an insoluble content of the pressure-sensitive adhesive composition remaining after being dipped in toluene at 60 C. for 24 hours and filtered through a 200-mesh filter (pore size of 200 m).

3. The composition according to claim 1, wherein the active energy ray-polymerizable compound is a multifunctional acrylate.

4. The composition according to claim 1, wherein the active energy ray-polymerizable compound satisfies Formula 2: ##STR00005## wherein R.sub.1 is hydrogen or an alkyl group having 1 to 4 carbon atoms, n is an integer of 2 or more, and X is a residue induced from a linear, branched, or cyclic alkyl group having 3 to 30 carbon atoms.

5. The composition according to claim 1, wherein the silane compound satisfying Formula 1 is included at 0.1 to 10 parts by weight relative to 100 parts by weight of the encapsulating resin.

6. The composition according to claim 1, wherein the tackifier is a hydrogenated cyclic olefin-based polymer.

7. The composition according to claim 1, wherein the tackifier is included at 5 to 100 parts by weight relative to 100 parts by weight of the encapsulating resin.

8. The composition according to claim 1, further comprising a radical initiator.

9. The composition according to claim 8, wherein the radical initiator is included at 0.2 to 20 parts by weight relative to 100 parts by weight of the active energy ray-polymerizable compound.

10. A pressure-sensitive adhesive film satisfying Equation 2, comprising: a pressure-sensitive adhesive layer including the pressure-sensitive adhesive composition of claim 1, wherein a peeling strength (peeling rate: 5 mm/sec, peeling angle: 180 degrees) of the pressure-sensitive adhesive layer with respect to a substrate after being maintained at 25 C. and a relative humidity of 50% for 1 hour is P gf/25 mm, and a peeling strength (peeling rate: 5 mm/sec, peeling angle: 180 degrees) of the pressure-sensitive adhesive layer with respect to a substrate after being maintained at 85 C. and a relative humidity of 85% for 1 hour is Q gf/25 mm:
Q1.3P.[Equation 2]

11. The film according to claim 10, wherein the pressure-sensitive adhesive film comprises a first layer having the pressure-sensitive adhesive layer and a second layer having a pressure-sensitive adhesive resin or an adhesive resin.

12. The film according to claim 10, which has a water vapor transmission rate in a thickness direction of 50 g/m.sup.2.Math.day or less when manufactured to have a thickness of 100 m.

13. The film according to claim 10, which has a light transmittance of 85% or more with respect to a visible-ray region.

14. The film according to claim 10, which has a haze of 3% or less.

15. An organic electronic device, comprising: a substrate; an organic electronic element formed on the substrate; and the pressure-sensitive adhesive film according to claim 10 encapsulating the organic electronic element.

16. A method of manufacturing an organic electronic device, comprising: applying the pressure-sensitive adhesive film of claim 10 to a substrate on which an organic electronic element is formed in order to cover the organic electronic element; and curing the pressure-sensitive adhesive film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIGS. 1 and 2 are cross-sectional views of pressure-sensitive adhesive films according to exemplary embodiments of the present invention; and

(2) FIG. 3 is a cross-sectional view of a product for encapsulating an organic electronic device according to an exemplary embodiment of the present invention.

DESCRIPTION OF REFERENCE NUMERALS

(3) 1, 2: pressure-sensitive adhesive film 11: pressure-sensitive adhesive layer 12: first film 21: second film 3: organic electronic device 31: substrate 32: organic electronic element 33: pressure-sensitive adhesive layer or encapsulating layer 34: cover substrate

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(4) Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the scope of the present invention is not limited to the following examples.

Example 1

(5) A coating solution was prepared by adding 90 g of a butyl rubber (Br268, EXXON) as an encapsulating resin, 10 g of a hydrogenated DCPD-based tackifier (SU-90, Kolon) as a tackifier, 15 g of tricyclodecane dimethanol diacrylate (M262, Miwon) as an active energy ray-polymerizable compound, 3 g of 3-methacryloxypropyl trimethoxysilane (Sigma Aldrich) as a silane compound, and 0.5 g of 2,2-dimethoxy-1,2-diphenylethane-1-one (Irgacure651, Ciba) as a radical initiator, and diluting the mixture in toluene to have a solid content of approximately 20 wt %.

(6) The prepared solution was coated on a released surface of release PET, and dried in an oven at 100 C. for 15 minutes, thereby manufacturing a pressure-sensitive adhesive film including a pressure-sensitive adhesive layer having a thickness of 20 m. Physical properties of the sample were measured after a UV ray was irradiated at 2 J/cm.sup.2 on the manufactured film.

Example 2

(7) A pressure-sensitive adhesive film was manufactured by the same method as described in Example 1, except that 10 g of 3-methacryloxypropyl trimethoxysilane (Sigma Aldrich) was used.

Comparative Example 1

(8) A pressure-sensitive adhesive film was manufactured by the same method as described in Example 1, except that 3-methacryloxypropyl trimethoxysilane (0 g) was not used.

Comparative Example 2

(9) A pressure-sensitive adhesive film was manufactured by the same method as described in Example 1, except that 90 g of butyl acrylate and 10 g of acrylic acid were used instead of the butyl rubber and hydrogenated DCPD-based tackifier used in Example 1.

(10) Hereinafter, physical properties were evaluated by the following methods in the Examples and Comparative Examples.

(11) 1. Measurement of Pressure-Sensitive Adhesive Strength

(12) A width of the pressure-sensitive adhesive film manufactured in Example or Comparative Example was set to 1 inch, and the film was maintained at 25 C. and a relative humidity of 50% for 1 hour, and then a peeling strength (peeling rate: 5 mm/sec, peeling angle: 180 degrees) of a pressure-sensitive adhesive layer of the pressure-sensitive adhesive film with respect to an OLED panel (a glass on which silicon nitride is inorganic-deposited) was measured.

(13) A width of the pressure-sensitive adhesive film manufactured in Example or Comparative Example was set to 1 inch, and the film was maintained at 85 C. and a relative humidity of 85% for 1 hour, and then a peeling strength (peeling rate: 5 mm/sec, peeling angle: 180 degrees) of a pressure-sensitive adhesive layer of the pressure-sensitive adhesive film with respect to an OLED panel (a glass on which silicon nitride is inorganic-deposited) was measured.

(14) The measurement was performed at constant temperature and constant humidity, and the peeling strength was measured using a texture analyzer according to ASTM3330.

(15) 2. Water Vapor Transmission Rate (WVTR)

(16) A resin composition was prepared by dissolving the resin used in Example or Comparative Example in a solvent. The resin composition was applied to a base film having a thickness of 38 m (release polyester film, RS-21G, SKC). Subsequently, the composition was dried at 110 C. for 10 minutes, thereby forming a film-type layer having a thickness of 100 m. Afterward, the base film was peeled, and then a WVTR of the film-type layer was measured in a thickness direction, while the layer was maintained at 100 F. and a relative humidity of 100%. The WVTR was measured according to a specification of ASTM F1249.

(17) 3. Measurement of Haze

(18) A haze of the pressure-sensitive adhesive film manufactured as described above was measured using a haze meter according to JIS K7105 standard test method.

(19) 4. Measurement of Release Peeling Strength

(20) A width of the pressure-sensitive adhesive film manufactured in Example or Comparative Example was set to 1 inch, and the film was maintained at 25 C. and a relative humidity of 50% for 1 week, and then a peeling strength (peeling rate: 5 mm/sec, peeling angle: 180 degrees) of the pressure-sensitive adhesive film with respect to release PET was measured.

(21) The measurement was performed at constant temperature and constant humidity, and the peeling strength was measured using a texture analyzer according to ASTM3330.

(22) TABLE-US-00001 TABLE 1 25 C. 85 C. Pressure- Pressure- sensitive sensitive Release adhesive adhesive peeling strength strength WVTR strength Haze (gf/inch) (gf/inch) (g/m.sup.2 .Math. day) (gf/inch) (%) Example 1 2108.6 3021.0 3 12 1.2 Example 2 2200 3021.0 3 55 3.2 Comparative 1816 1075 3 7 1.2 Example 1 Comparative 1980 500 1200 10 1.0 Example 2

(23) As shown in Table 1, Example 1 according to the present invention can realize excellent durability and reliability under harsh conditions such as high temperature and high humidity by preventing a decrease in an interface pres sure-sensitive adhesive strength due to moisture penetration at high temperature and high humidity. On the other hand, Comparative Example 1 showed a decrease in a pressure-sensitive adhesive strength at a high temperature, and Comparative Example 3 showed a decrease in an interface pressure-sensitive adhesive strength due to moisture penetration.