Adhesive encapsulating composition and electronic devices made therewith

• US 8,232,350 B2
• Filed: 04/28/2009
• Issued: 07/31/2012
• Est. Priority Date: 06/02/2008
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Fujita, Jun, Kobori, Nami, Bharti, Vivek, McCormick, Fred B., Mollenhauer, Serena L.
• Primary Examiner(s): Nutter, Nathan M
• Application Number:
  US12/995,565
• Publication Number:
  US 20110105637A1
• Time in Patent Office: 1,190 Days
• Field of Search: 525/191, 525/193, 525/221, 525/222, 524/515
• US Class Current: 525/191
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 23/22 Copolymers of isobutene; Butyl rubber ; Homo- or copolymers of other iso-olefins
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C09J 123/22 Copolymers of isobutene; Butyl rubber ; Homo- or copolymers of other iso-olefines
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: Y10T 428/2891 including addition polymer from alpha-beta unsaturated carboxylic acid [e.g., acrylic acid, methacrylic acid, etc.] Or derivative thereof
• CPC Class Codes: Y10T 428/31935 Ester, halide or nitrile of addition polymer

Abstract

Adhesive encapsulating compositions for use in electronic devices such as organic electroluminescent devices, touch screens, photovoltaic devices, and thin film transistors are disclosed herein. The adhesive encapsulating compositions include pressure sensitive adhesives comprising one or more polyisobutylene resins, in combination with optional multifunctional (meth)acrylate monomers and/or optional tackifiers.

Claims

1. An adhesive encapsulating composition for use in an electronic device, comprising:

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a multifunctional (meth)acrylate monomer;

wherein the adhesive encapsulating composition is substantially free of tackifier.

2. The adhesive encapsulating composition of claim 1, wherein the first isobutylene resin has a weight average molecular weight of greater than about 1,000,000 g/mol.

3. The adhesive encapsulating composition of claim 1, wherein the first polyisobutylene comprises at least about 50 wt. % of the total weight of the adhesive encapsulating composition.

15. The adhesive encapsulating composition of claim 1, wherein the multifunctional (meth)acrylate monomer comprises an aliphatic di(meth)acrylate.

16. The adhesive encapsulating composition of claim 1, wherein the multifunctional (meth)acrylate monomer comprises a multifunctional (meth)acrylate/epoxy monomer.

17. The adhesive encapsulating composition of claim 1, wherein the adhesive encapsulating composition is photopolymerizable and comprises a photoinitiator.

18. The adhesive encapsulating composition of claim 1, wherein the adhesive encapsulating composition is thermally polymerizable and comprises a thermal initiator.

19. The adhesive encapsulating composition of claim 1, further comprising particles.

20. An adhesive encapsulating film comprising an adhesive layer disposed on a substrate, the adhesive layer comprising the adhesive encapsulating composition of claim 1.

21. An adhesive encapsulating film comprising an adhesive layer disposed on a substrate, and a gas-barrier film disposed on the adhesive layer opposite the substrate, the adhesive layer comprising the adhesive encapsulating composition of claim 1.

22. An adhesive encapsulating film comprising an adhesive layer disposed on a substrate, and a trapping layer disposed either on the adhesive layer opposite the substrate or between the adhesive layer and the substrate, the adhesive layer comprising the adhesive encapsulating composition of claim 1.

4. An adhesive encapsulating composition for use in an electronic device, comprising:

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a second polyisobutylene resin having a weight average molecular weight of less than about 100,000 g/mol,

wherein the adhesive encapsulating composition is substantially free of tackifier.

5. The adhesive encapsulating composition of claim 4, wherein the first isobutylene resin has a weight average molecular weight of greater than about 400,000 g/mol.

6. The adhesive encapsulating composition of claim 4, wherein the first polyisobutylene comprises at least about 50 wt. % of the total weight of the adhesive encapsulating composition.

7. The adhesive encapsulating composition of claim 4, further comprising a multifunctional (meth)acrylate monomer.

8. The adhesive encapsulating composition of claim 7, comprising:

from about 50 to about 80 wt. % of the first polyisobutylene resin;

from about 10 to about 30 wt. % of the second polyisobutylene resin; and

from about 10 to about 20 wt. % of the multifunctional (meth)acrylate monomer;

all relative to the total weight of the adhesive encapsulating composition.

9. An adhesive encapsulating composition for use in an electronic device, comprising:

a second polyisobutylene resin having a weight average molecular weight of less than about 300,000 g/mol;

a multifunctional (meth)acrylate monomer; and

a tackifier,

wherein the adhesive encapsulating composition is free of a first polyisobutylene having a weight average molecular weight of greater than about 300,000 g/mol.

10. The adhesive encapsulating composition of claim 9, wherein the second isobutylene resin has a weight average molecular weight of less than about 100,000 g/mol.

11. The adhesive encapsulating composition of claim 9, comprising:

from about 10 to about 50 wt. % of the second polyisobutylene resin;

from about 10 to about 40 wt. % of the multifunctional (meth)acrylate monomer;

from about 30 to about 60 wt. % of the tackifier;

all relative to the total weight of the adhesive encapsulating composition.

12. An adhesive encapsulating composition for use in an electronic device, comprising:

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol, wherein the first polyisobutylene resin comprises 20 wt. % or less of the total weight of the adhesive encapsulating composition;

a second polyisobutylene resin having a weight average molecular weight of less than about 300,000 g/mol;

a multifunctional (meth)acrylate monomer; and

a tackifier.

13. The adhesive encapsulating composition of claim 12, wherein the first isobutylene resin has a weight average molecular weight of greater than about 1,000,000 g/mol.

14. The adhesive encapsulating composition of claim 12, comprising:

from about 10 to about 30 wt. % of the second polyisobutylene resin;

from about 10 to about 30 wt. % of the multifunctional (meth)acrylate monomer;

from about 40 to about 60 wt. % of the tackifier;

all relative to the total weight of the adhesive encapsulating composition.

23. An organic electroluminescent device comprising:

a pair of opposing electrodes;

a light-emitting unit having at least an organic light-emitting layer, the light-emitting unit disposed between the pair of opposing electrodes; and

an adhesive encapsulating composition disposed on, above, or around the light-emitting unit, the adhesive encapsulating composition comprising;

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a multifunctional (meth)acrylate monomer;

wherein the adhesive encapsulating composition is substantially free of tackifier.

24. The organic electroluminescent device of claim 23, wherein the device is flexible.

25. A touch screen comprising:

a glass or polymeric substrate;

a substantially transparent conductive metal disposed on the substrate; and

an adhesive encapsulating composition disposed on, above, or around the metal, the adhesive encapsulating composition comprising;

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a multifunctional (meth)acrylate monomer;

wherein the adhesive encapsulating composition is substantially free of tackifier.

26. A photovoltaic device comprising:

a photovoltaic cell or an array of photovoltaic cells; and

an adhesive encapsulating composition disposed on, above, or around the photovoltaic cell or any one of the photovoltaic cells of the array of photovoltaic cells, the adhesive encapsulating composition comprising;

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a multifunctional (meth)acrylate monomer;

wherein the adhesive encapsulating composition is substantially free of tackifier.

27. A thin film transistor comprising:

a semiconductor layer; and

an adhesive encapsulating composition disposed on, above, or around the semiconductor layer, the adhesive encapsulating composition comprising;

a first polyisobutylene resin having a weight average molecular weight of greater than about 300,000 g/mol; and

a multifunctional (meth)acrylate monomer;

wherein the adhesive encapsulating composition is substantially free of tackifier.