Claims
- 1. A silicone pressure sensitive adhesive having improved high temperature stability comprising:
- (a) an aromatic hydrocarbon soluble resin copolymer comprising R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units where each R individually represents a monovalent hydrocarbon radical containing no more than six carbon atoms where the total number of R radicals having olefinic unsaturation is between 0 and 0.25 percent, there being from about 0.6 to about 0.9 R.sub.3 SiO.sub.1/2 units for every SiO.sub.4/2 unit;
- (b) a hydroxyl, vinyl or hydride end-stopped diorganopolysiloxane and
- (c) from about 200 to about 500 parts per million metal of oil- or organic-soluble metal salts based on the total silicone weight of (a) and (b).
- 2. A silicone pressure sensitive adhesive as defined in claim 1 wherein component (a) is present in an amount ranging from about 80 to about 40 parts by weight and component (b) is present in an amount ranging from about 20 to about 60 parts by weight based on 100 parts by weight of (a) and (b) together.
- 3. A silicone pressure sensitive adhesive as defined in claim 2 wherein component (a) is present in an amount ranging from 80 to about 50 parts by weight and component (b) is present in an amount ranging from about 20 to about 50 parts by weight based on 100 parts by weight of (a) and (b) together.
- 4. A silicone pressure sensitive adhesive as defined in claim 1 wherein said component (b) comprises a hydroxyl end-stopped diorganopolysiloxane of the general formula: ##STR2## wherein each R.sup.1 individually is a radical selected from the group consisting of alkyl radicals, alkenyl radicals, cyclic hydrocarbon radicals and aryl radicals wherein x is a number sufficient to provide a viscosity of from about 100,000 to 500,000,000 centipoise at 25.degree. C.
- 5. A silicone pressure sensitive adhesive as defined in claim 4 wherein each said R.sup.1 is independently selected from the group consisting of methyl, ethyl, propyl, hexyl, octyl, vinyl, allyl, propenyl, butenyl, hexenyl, cyclohexyl, cyclohexenyl, phenyl, 2-phenylethyl, tolyl and benzyl.
- 6. A silicone pressure sensitive adhesive as defined in claim 5 wherein at least 95 percent of the organic radicals in components (a) and (b), R and R.sup.1 are methyl.
- 7. A silicone pressure sensitive adhesive as defined in claim 6 wherein all of the organic radicals in components (a) and (b) are methyl.
- 8. A silicone pressure sensitive adhesive as defined in claim 7 wherein said hydroxyl end-stopped organopolysiloxane component (b) comprises silanol-stopped polydimethylsiloxanes.
- 9. A silicone pressure sensitive adhesive as defined in claim 1 wherein said component (b) comprises a mixture of vinyl and hydride end-stopped organopolysiloxane fluids.
- 10. A silicone pressure sensitive adhesive as defined in claim 1 wherein said component (c) is present in an amount ranging from 200 parts per million metal to 2500 parts per million metal based on total silicone weight.
- 11. A silicone pressure sensitive adhesive as defined in claim 1 wherein said oil or organic soluble metal salt comprises a metal salt of a carboxylic acid having from about 2 to about 18 carbon atoms.
- 12. A silicone pressure sensitive adhesive as defined in claim 1 wherein the metal is selected from rare earth metals selected from lanthanum, cerium, praesodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium.
- 13. A silicone pressure sensitive adhesive as defined in claim 1 wherein the metal comprises a transition metal.
- 14. A silicone pressure sensitive adhesive as defined in claim 13 wherein said transition metal is selected from the group consisting of zirconium, titanium, nickel, iron, vanadium, chromium, maganese, cobalt and copper.
- 15. A silicone pressure sensitive adhesive as defined in claim 1 wherein the metal is selected from the group consisting of magnesium, calcium, barium, aluminum and tin.
- 16. A silicone pressure sensitive adhesive as defined in claim 12 wherein said oil or organic soluble metal salt comprises a rare earth metal 2-ethylhexanoate, rare earth metal octoate or a mixture thereof.
- 17. A silicone pressure sensitive adhesive as defined in claim 12 wherein said oil- or organic-soluble metal salt comprises cerium 2-ethylhexanoate, cerium octoate or a mixture thereof.
- 18. An improved silicone pressure adhesive having improved high temperature stability comprising:
- (a) an aromatic soluble resin copolymer comprising R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units where each R individually represents a monovalent hydrocarbon radical containing no more than six carbon atoms, there being from about 0.6 to about 0.9 R.sub.3 SiO.sub.1/2 units for every SiO.sub.4/2 unit;
- (b) a hydroxyl, vinyl or hydride end-stopped diorganopolysiloxane;
- the improvement comprising:
- adding (c) from about 200 to about 500 parts per million metal of oil or organic soluble metal salts based on the total silicone weight of (a) and (b).
- 19. A silicone pressure sensitive adhesive as defined in claim 18 wherein said oil or organic soluble metal salt comprises a metal salt of a carboxylic acid having from about 2 to about 18 carbon atoms.
- 20. A silicone pressure sensitive adhesive as defined in claim 19 wherein said oil or organic soluble metal salt comprises a rare earth metal octoate, a rare earth metal 2-ethylhexanoate or a mixture thereof.
- 21. A silicone pressure sensitive adhesive as defined in claim 20 wherein said oil or organic soluble metal salt comprises cerium 2-ethylhexanoate, cerium octoate or a mixture thereof.
- 22. A method for improving the high temperature stability of a silicone pressure adhesive comprising (i) adding to a silicone pressure adhesive comprising (a) a benzene soluble resin copolymer comprising R.sub.3 SiO.sub.1/2 units and SiO.sub.4/2 units where each R individually represents a monovalent hydrocarbon radical containing no more than six carbon atoms, there being from about 0.6 to about 0.9 R.sub.3 SiO.sub.1/2 units for every SiO.sub.4/2 unit; and (b) a hydroxyl, vinyl or hydride end-stopped diorganopolysiloxane; (ii) from about 200 to about 500 parts per million metal of (c) oil- or organic-soluble metal salts based on the total silicone weight of (a) and (b).
- 23. A silicone pressure sensitive adhesive as defined in claim 22 wherein said component (c) is present in an amount ranging from 200 parts per million metal to 2500 parts per million metal based on total silicone weight.
- 24. A silicone pressure sensitive adhesive as defined in claim 22 wherein said oil or organic soluble metal salt comprises a metal salt of a carboxylic acid having from about 2 to about 18 carbon atoms.
- 25. A silicone pressure sensitive adhesive as defined in claim 24 wherein said oil or organic soluble metal salt comprises a rare earth metal octoate, a rare earth metal 2-ethylhexanoate or mixtures thereof.
- 26. A silicone pressure sensitive adhesive as defined in claim 21 wherein said oil or organic soluble metal salt comprises cerium 2-ethylhexanoate, cerium octoate, or mixtures thereof.
Parent Case Info
This is a divisional of application Ser. No. 08/172,673 filed on Dec. 22, 1993, now U.S. Pat. No. 5,491,811, which is a continuation of application Ser. No. 07/895,297, filed on Jun. 8, 1992, now abandoned.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0131854 |
Jan 1985 |
EPX |
1272682 |
Oct 1989 |
JPX |
Non-Patent Literature Citations (3)
Entry |
Clifford F. Lewis, "Adhesive Films Take on Tougher Jobs", ME, Jan. 1986, pp. 21-25. |
Duane F. Merrill, "Silicone Pressure Sensitive Adhesives", The Society for the Advancement of Material and Process Engineering, Jul. 1985. |
Frank J. Modic, "Silicone Pressure-Sensitive Adhesives: Their properties and Applications", Adhesives Age, Dec. 1962, pp. 36-38. |
Divisions (1)
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Number |
Date |
Country |
Parent |
172673 |
Dec 1993 |
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Continuations (1)
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Number |
Date |
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Parent |
895297 |
Jun 1992 |
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