Search International and National Patent Collections
Some content of this application is unavailable at the moment.
If this situation persists, please contact us atFeedback&Contact
1. (WO1998050480) ADHESIVE COMPOSITIONS THAT ARE REMOVABLE AFTER THERMOSETTING
Note: Text based on automatic Optical Character Recognition processes. Please use the PDF version for legal matters

What is claimed is:
1. A thermosettable adhesive composition comprising
a polyepoxide resin;
a curing agent; and
a plurality of microspheres, said microspheres said polyepoxide resin, and said curing agent and the relative amounts thereof, being selected such that upon cure said composition is capable of forming a semi-structural bond to a substrate and is cleanly thermally removable from said substrate.

2. The composition of claim 1, wherein upon cure said composition exhibits no greater than about 35% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

3. The composition of claim 1, wherein upon cure said composition exhibits no greater than about 20% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

4. The composition of claim 1, wherein upon cure said composition exhibits a peel adhesion strength of at least about 3.5 N/cm measured on an abraded phenolic resin impregnated fiberglass substrate at room temperature.

5. The composition of claim 1, wherein upon cure said composition exhibits a peel adhesion strength of at least about 10.5 N/cm measured on an abraded phenolic resin impregnated fiberglass substrate at room temperature.

6. The composition of claim 1, wherein upon cure said composition exhibits a peel adhesion strength of at least about 3.5 N/cm measured on a polycarbonate substrate at room temperature.

7. The composition of claim 1, wherein upon cure said composition exhibits a peel adhesion strength of at least about 10.5 N/cm measured on a polycarbonate substrate at room temperature.

8. The composition of claim 1, wherein upon cure said composition exhibits a peel adhesion strength of at least 3.5 N/cm measured on an abraded phenolic resin impregnated fiberglass substrate at room temperature and no greater than about 35% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

9. The composition of claim 1, further comprising a flame retardant.

10. The composition of claim 1, further comprising no greater than 20% by weight of a flame retardant.

1 1. The composition of claim 1, wherein upon cure said composition exhibits no greater than about 35% retention of initial peel adhesion strength at a temperature of greater than about 50°C.

12. The composition of claim 1, wherein upon cure said composition exhibits no greater than about 35%) retention of initial peel adhesion strength at a temperature of at least about 15°C greater than said upper use temperature.

13. The composition of claim 1, wherein the ratio of weight of said polyepoxide resin to weight of said microspheres is between about 70:30 and about 35:65.

14. The composition of claim 1, wherein said composition cures at a temperature greater than room temperature.

15. The composition of claim 1, wherein the composition cures at a temperature between about room temperature and about 200°C.

16. The composition of claim 1, wherein said microspheres comprise tacky microspheres.

17. The composition of claim 1, wherein said microspheres comprise solid microspheres.

18. The composition of claim 1, wherein said microspheres comprise hollow microspheres.

19. The composition of claim 1, wherein said microspheres comprise tack-free microspheres.

20. The composition of claim 1, wherein said microspheres comprise tacky, solid microspheres.

21. The composition of claim 1, wherein said microspheres have an average diameter between about 1 micrometer and about 20 micrometers.

22. The composition of claim 1, wherein said microspheres comprise the reaction product of isooctyl acrylate, acrylic acid and poly(ethylene oxide)acrylate.

23. The composition of claim 1, wherein said compositionis dispersed in water.

24. The composition of claim 1, wherein said composition is tack-free prior to cure.

25. The composition of claim 1. wherein said curing agent comprises a heat-activated curing agent.

26. The composition of claim 1, wherein said curing agent comprises a photolytically-activatedcuring agent.

27. The composition of claim 1, wherein said curing agent comprises a blend of an epoxy homopolymerizationcatalyst and an addition curing agent.

28. The composition of claim 27, wherein said catalyst is selected from the group consisting of tertiary amines, imidazoles, substituted derivatives of imidazoles and combinations thereof.

29. The composition of claim 1, wherein upon cure said composition is capable of forming a semi-structural bond to a phenolic resin impregnated fiberglass substrate.

30. A thermosettable adhesive composition comprising
between about 35 and about 70 parts by weight of a polyepoxide resin;
a curing agent; and
between about 30 and about 65 parts by weight microspheres, said composition, upon cure, being capable of forming a semi-structural bond to a substrate and being cleanly thermally removable from said substrate.

31. The composition of claim 30, wherein upon cure said composition exhibits a peel adhesion of at least about 3.5 N/cm measured on a polycarbonate substrate at room temperature, and no greater than about 35%> retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

32. An article comprising: a substrate having a surface, at least a portion of which is provided with a thermosettable adhesive composition comprising
a polyepoxide resin,
a curing agent, and
a plurality of microspheres,
said microspheres, said polyepoxide resin, and said curing agent and the relative amounts thereof, being selected such that upon cure said composition is capable of forming a semi-structural bond and is cleanly thermally removable.

33. The article of claim 32, wherein upon cure said composition exhibits no greater than about 20%) retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

34. The article of claim 32, wherein upon cure said composition exhibits a peel adhesion of at least about 3.5 N/cm measured on phenolic resin impregnated fiberglass substrate at room temperature, and no greater than about 35%> retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

35. The article of claim 32, wherein said substrate comprises a release liner.

36. The article of claim 32, further comprising a second substrate in contact with said adhesive composition.

37. The article of claim 36, wherein said first substrate is a more rigid substrate and said second substrate is a more flexible substrate.

38. The article of claim 36, wherein said second substrate comprises a film.

39. The article of claim 32, wherein the ratio of weight of said polyepoxide resin to weight of said microspheres is between about 70:30 and about 35:65.

40. The article of claim 32, wherein upon cure said composition is capable of forming a semi-structural bond to a phenolic resin impregnated fiberglass substrate.

41. An article comprising:
a substrate having a surface, at least a portion of which is provided with a thermosettable adhesive composition comprising
a polyepoxide resin,
a curing agent, and
a plurality of microspheres,
said microspheres, said polyepoxide resin, and said curing agent and the relative amounts thereof, being selected such that upon cure said composition is capable of forming a semi-structural bond to said substrate and is cleanly thermally removable from said substrate.

42. A method for making an article comprising providing a
thermosettable adhesive composition on at least a portion of a substrate,
said composition comprising
a polyepoxide resin,
a curing agent, and
a plurality of microspheres,
said microspheres, said polyepoxide resin, and said curing agent and the relative amounts thereof, being selected such that upon cure said composition is capable of forming a semi-structural bond and is cleanly thermally removable.

43. The method of claim 42, further comprising contacting said composition with a second substrate.

44. The method of claim 43 , wherein said second substrate is a more flexible substrate and said first substrate is a more rigid substrate.

45. The method of claim 42, further comprising curing said composition.

46. The method of claim 42, wherein upon cure said composition exhibits no greater than about 20% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

47. The method of claim 42, wherein upon cure said composition exhibits a peel adhesion of at least about 3.5 N/cm measured on a phenolic resin impregnated fiberglass substrate at room temperature, and no greater than about 35% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

48. The method of claim 42, wherein the ratio of weight of said polyepoxide resin to weight of said microspheres is between about 70:30 and about 35:65.

49. The method of claim 42, further comprising a flame retardant.

50. The method of claim 42, wherein upon cure said composition is capable of forming a semi-structural bond to a phenolic resin impregnated fiberglass substrate.

51. A method for making an adhesive article, said method comprising:
contacting a surface with an article, said article comprising a thermosettable adhesive composition comprising
a polyepoxide resin,
a curing agent, and a plurality of microspheres, said microspheres, said
polyepoxide resin and said curing agent and the relative amounts thereof, being selected such that upon cure said composition is capable of forming a semi-structural bond to a substrate and is cleanly thermally removable
from said substrate; and
heating said composition to a temperature sufficient to cure said composition.

52. The method of claim 51, further comprising contacting a substrate with said composition before heating said composition.

53. The method of claim 51, wherein upon cure said composition exhibits a peel adhesion strength of at least about 3.5 N/cm measured on a phenolic resin impregnated fiberglass substrate at room temperature, and no greater than about 35% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

54. A method for removing an article from a surface comprising:
heating an article comprising a first substrate, a second substrate and a cured thermosettable adhesive composition disposed between said first and said second substrates, said cured composition forming a semi-structural bond between said substrates, said cured composition comprising a crosslinked polyepoxide resin and a plurality of microspheres,
to a temperature greater than the use temperature of said composition; and
cleanly removing said composition from one of said substrates.

55. The method of claim 54, wherein said adhesive composition exhibits a peel adhesion strength of at least about 3.5 N/cm measured at room temperature, and no greater than about 35%> retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

56. A method for making a thermosettable adhesive composition cleanly thermally removable by incorporating a plurality of microspheres therein, said composition, upon cure, being capable of forming a semi-structural bond to a substrate.

57. The method of claim 56, wherein upon cure said composition exhibits no greater than about 20% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

58. The method of claim 56, wherein said composition comprises a polyepoxide resin, a curing agent and a plurality of microspheres.

59. The method of claim 56, wherein upon cure said composition exhibits a peel adhesion strength of at least about 3.5 N/cm measured on an abraded phenolic resin impregnated fiberglass substrate at room temperature and no greater than about 35% retention of initial peel adhesion strength at a temperature greater than the upper use temperature.

60. A method of making an article comprising:
providing a curing agent on a substrate;
contacting said curing agent with a composition comprising a polyepoxide resin and a plurality of microspheres, said curing agent, said
polyepoxide resin and said microspheres and the relative amounts thereof, being selected so as to provide a thermosettable adhesive composition that is capable of forming a semi-structural bond to said substrate and is cleanly thermally removable from said substrate at a temperature greater than the use temperature.