Release coating compositions

• US 5,578,381 A
• Filed: 08/30/1995
• Issued: 11/26/1996
• Est. Priority Date: 08/31/1994
• Status: Expired due to Term

• Current Assignee: Dow Corning Toray Silicone Company Limited (Dow, Inc.)
• Original Assignee: Dow Corning Toray Silicone Company Limited (Dow, Inc.)
• Inventors: Nishiumi, Wataru, Kobayashi, Hideki, Hamada, Yuji
• Primary Examiner(s): Marquis, Melvyn I.
• Application Number:
  US08/521,159
• Time in Patent Office: 454 Days
• Field of Search: 528/15, 528/35, 528/20, 528/21, 528/12, 528/18, 524/792, 524/862, 524/770, 524/765, 524/755, 524/726, 524/751, 524/742, 524/773, 427/387, 428/447
• US Class Current: 428/447
• CPC Class Codes: C08L 83/00 Compositions of macromolecular compounds obtained by reactions forming in the main chain of the macromolecule a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon only; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 83/14 in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms C08L83/10 takes precedence
• CPC Class Codes: C09D 183/14 in which at least two but not all the silicon atoms are connected by linkages other than oxygen atoms C09D183/10 takes precedence
• CPC Class Codes: C09J 2483/005 in the release coating
• CPC Class Codes: C09J 7/401 characterised by the release coating composition
• CPC Class Codes: Y10T 428/31663 As siloxane, silicone or silane

Abstract

The present invention relates to a release coating composition comprising an organopolysiloxane having fluorine containing organic groups and alkenyl groups, an organohydrogensiloxane, and a platinum-containing catalyst. The present invention also relates to a release coating composition comprising an organopolysiloxane having fluorine containing organic groups and silicon-bonded hydrogen groups, an alkenyl functional organopolysiloxane, and a platinum-containing catalyst. The curable silicone release coating compositions of this invention have excellent release properties from various tacky substances, especially silicone-based pressure sensitive adhesives, after curing, and also have excellent bonding characteristics when applied to various substrates.

Claims

1. A curable silicone release coating composition comprising:

(A) 100 parts by weight of an organosilicon compound having its unit formula selected from;

##STR8## wherein R is a monovalent hydrocarbon group having from 1 to 10 carbon atoms and free of aliphatic unsaturation or a haloalkyl group, R¹ is a fluorine-containing monovalent organic group having from 6 to 16 carbon atoms and having at least 4 --CF₂ -- groups, R² is selected from R or an alkenyl group having from 2 to 10 carbon atoms, R³ is an alkylene group having from 2 to 10 carbon atoms, a, b, c, and d are positive numbers, m has a value of 0 or 1, n is an integer having a value of 0 to 2, and wherein the organosilicon compound has a weight average molecular weight of at least 1,000, with the proviso that there is at least two silicon-bonded alkenyl groups per molecule;

(B) 0.3 to 40 parts by weight of an organohydrogenpolysiloxane having at least 3 silicon-bonded hydrogen atoms per molecule; and

(C) 0.1 to 1,000 parts by weight of a platinum-containing catalyst, said weight being based on the parts by weight of platinum per one million parts by weight of the total of (A) and (B).

2. A composition according to claim 1, wherein R is selected from methyl, ethyl, propyl, butyl, pentyl, octyl, phenyl, tolyl, xylyl, benzyl, phenethyl, 3-chloropropyl, or 3,3 3-trifluoropropyl, R¹ is selected from a group having the formula C_p F_2p+1 --X--, a group having the formula C_p F_2p+1 --X--O--X--, or a group having the formula:

##STR9## wherein p has a value of at least 4 and X is an alkylene group, R² is selected from vinyl, allyl, butenyl, pentenyl, hexenyl, or octenyl, and R³ is selected from ethylene, propylene, butylene, pentylene, hexylene, or octylene.

3. A composition according to claim 2, wherein X is selected from methylene, ethylene, propylene, or butylene.

4. A composition according to claim 1 wherein (A) is an organosilicon compound having its unit formula selected from:

##STR10## wherein Me denotes methyl, Vi denotes vinyl, Ph denotes phenyl, and a, b, c, and d are positive numbers.

5. A composition according to claim 1 wherein (B) is selected from trimethylsiloxy-endblocked dimethylsiloxane-methylhydrogensiloxane copolymers, dimethylhydrogensiloxy-endblocked methyl(perfluorobutylethyl)siloxane-methylhydrogensiloxane copolymers, trimethylsiloxy-endblocked methyl(perfluorobutylethyl)siloxane-dimethylsiloxane-methylhydrogensiloxane copolymers, trimethylsiloxy-endblocked methyl(perfluorohexylethyl)siloxane-methylhydrogenpolysiloxane copolymers, or copolymers comprising methyl(perfluorobutylethyl)siloxane units, dimethylhydrogensiloxane units, and SiO₂ units.

6. A composition according to claim 1, wherein (C) is selected from fine particle platinum adsorbed on carbon powder, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid and olefins, complexes of chloroplatinic acid and vinylsiloxane, or platinum black.

7. A composition according to claim 1, wherein the composition further comprises an inhibitor to inhibit the catalytic activity of platinum-containing catalyst (C).

8. A composition according to claim 7, wherein the inhibitor is selected from ethynylcyclohexanol, 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-penten-3-ol, phenylbutynol, diallyl maleate, dimethyl maleate, diethyl fumarate, diallyl fumarate, bis-(methoxyisopropyl) maleate, 3-methyl-3-penten-1-yne, 3,5-dimethyl-1-hexyn-3-yne, cyclic tetramethylvinylsiloxanes, or benzotriazole.

9. A composition according to claim 1, wherein the composition further comprises an organic solvent selected from trifluoromethylbenzene, 1,3-bis(trifluoromethyl)benzene, methylpentafluorobenzene, benzene, toluene, xylene, heptane, hexane, pentane, isooctane, acetone, methylethylketone, methylisobutylketone, ethyl acetate, butyl acetate, tetrahydrofuran, diethylether, methanol, ethanol, propanol, butanol, dimethylformamide, dimethylsulfoxide, or mixtures thereof.

10. A composition according to claim 7, wherein the composition further comprises an organic solvent selected from trifluoromethylbenzene, 1,3-bis(trifluoromethyl)benzene, methylpentafluorobenzene, benzene, toluene, xylene, heptane, hexane, pentane, isooctane, acetone, methylethylketone, methylisobutylketone, ethyl acetate, butyl acetate, tetrahydrofuran, diethylether, methanol, ethanol, propanol, butanol, dimethylformamide, dimethylsulfoxide, or mixtures thereof.

11. A composition according to claim 7, wherein the composition further comprises a bath life extender compound in a total amount sufficient to further retard the curing reaction at room temperature.

12. A composition according to claim 11, wherein the bath life extender is selected from tetradecanols, pentanols, hexanols, heptanols, octanols, benzyl alcohol, water, phenol, methylphenyl carbinol, 2-phenylethyl alcohol, allyl alcohol, or cyclohexanol.

13. A curable silicone release coating composition comprising:

(A'"'"') 100 parts by weight of an organosilicon compound having its unit formula selected from;

##STR11## wherein R is a monovalent hydrocarbon group having from 1 to 10 carbon atoms and free of aliphatic unsaturation or a haloalkyl group, R¹ is a fluorine-containing monovalent organic group having from 6 to 16 carbon atoms and having at least 4 --CF₂ -- group R² is selected from hydrogen or R, R³ is an alkylene group having from 2 to 10 carbon atoms, a, b, c, and d are positive numbers, m has a value of 0 or 1, n is an integer having a value of 0 to 2, and wherein the organosilicon compound has a weight average molecular weight of at least 1,000 with the proviso that there is at least two silicon-bonded hydrogen groups per molecule;

(B'"'"') 0.3-40 parts by weight of an organopolysiloxane having at least 3 silicon-bonded alkenyl groups per molecule; and

(C'"'"') 0.1 to 1,000 parts by weight of a platinum-containing catalyst, said weight being based on the parts by weight of platinum per one million parts by weight of the total of (A'"'"') and (B'"'"').

14. A composition according to claim 13, wherein R is selected from methyl, ethyl, propyl, butyl, pentyl, octyl, phenyl, tolyl, xylyl, benzyl, phenethyl, 3-chloropropyl, or 3,3 3-trifluoropropyl, R¹ is selected from a group having the formula C_p F_2p+1 --X--, a group having the formula C_p F_2p+1 --X--O--X--, or a group having the formula:

##STR12## wherein p has a value of at least 4 and X is an alkylene group, and R³ is selected from ethylene, propylene, butylene, pentylene, hexylene, or octylene.

15. A composition according to claim 13, wherein (A'"'"') is an organosilicon compound having its unit formula selected from:

##STR13## wherein Me denotes methyl, Ph denotes phenyl, and a, b, c, and d are positive numbers.

16. A composition according to claim 13, wherein (B'"'"') is selected from dimethylvinylsiloxy-endblocked methylvinylpolysiloxanes, dimethylvinylsiloxy-endblocked dimethylsiloxane-methylvinylsiloxane copolymers, dimethylvinylsiloxy-endblocked methyl(perfluorobutylethyl)siloxane-methylvinylsiloxane copolymers, trimethylsiloxy-endblocked methyl(perfluorobutylethyl)siloxane-dimethylsiloxane-methylvinylsiloxane copolymers, trimethylsiloxy-endblocked dimethylsiloxane-methylvinylsiloxane copolymers, trimethylsiloxy-endblocked methylvinylpolysiloxanes, trimethylsiloxy-endblocked methyl(perfluorohexylethyl)siloxane-methylvinylpolysiloxane copolymers, or copolymers comprising methyl(perfluorobutylethyl)siloxane units, methylvinylsiloxane units, and SiO₂ units.

17. A composition according to claim 13, wherein (C'"'"') is selected from fine particle platinum adsorbed on carbon powder, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid and olefins, complexes of chloroplatinic acid and vinylsiloxanes, or platinum black.

18. A composition according to claim 13, wherein the composition further comprises an inhibitor to inhibit the catalytic activity of platinum-containing catalyst (C'"'"').

19. A composition according to claim 18, wherein the inhibitor is selected from ethynylcyclohexanol, 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-penten-3-ol, phenylbutynol, diallyl maleate, dimethyl maleate, diethyl fumarate, diallyl fumarate, bis-(methoxyisopropyl) maleate, 3-methyl-3-penten-1-yne, 3,5-dimethyl-1-hexyn-3-yne, cyclic tetramethylvinylsiloxanes, or benzotriazole.

20. A composition according to claim 13, wherein the composition further comprises an organic solvent selected from trifluoromethylbenzene, 1,3-bis(trifluoromethyl)benzene, methylpentafluorobenzene, benzene, toluene, xylene, heptane, hexane, pentane, isooctane, acetone, methylethylketone, methylisobutylketone, ethyl acetate, butyl acetate, tetrahydrofuran, diethylether, methanol, ethanol, propanol, butanol, dimethylformamide, dimethylsulfoxide, or mixtures thereof.

21. A composition according to claim 18, wherein the composition further comprises an organic solvent selected from trifluoromethylbenzene, 1,3-bis(trifluoromethyl)benzene, methylpentafluorobenzene, benzene, toluene, xylene, heptane, hexane, pentane, isooctane, acetone, methylethylketone, methylisobutylketone, ethyl acetate, butyl acetate, tetrahydrofuran, diethylether, methanol, ethanol, propanol, butanol, dimethylformamide, dimethylsulfoxide, or mixtures thereof.

22. A composition according to claim 18, wherein the composition further comprises a bath life extender compound in a total amount sufficient to further retard the curing reaction at room temperature.

23. A composition according to claim 22, wherein the bath life extender is selected from tetradecanols, pentanols, hexanols, heptanols, octanols, benzyl alcohol, water, phenol, methylphenyl carbinol, 2-phenylethyl alcohol, allyl alcohol, or cyclohexanol.

24. A cured coating prepared by:

(I) coating a curable silicone release coating composition on the surface of a substrate wherein the coating composition comprises;

(A) 100 parts by weight of an organosilicon compound having its unit formula selected from;

##STR14## wherein R is a monovalent hydrocarbon group having from 1 to 10 carbon atoms and free of aliphatic unsaturation, R¹ is a fluorine-containing monovalent organic group having from 6 to 16 carbon atoms and having at least 4 --CF₂ groups, R² is selected from R or an alkenyl group having from 2 to 10 carbon atoms, R³ is an alkylene group having from 2 to 10 carbon atoms, a, b, c, and d are positive numbers, m has a value of 0 or 1, n is an integer having a value of 0 to 2, and wherein the organosilicon compound has a weight average molecular weight of at least 1,000, with the proviso that there is at least two silicon-bonded alkenyl groups per molecule;

(B) 0.3 to 40 parts by weight of an organohydrogenpolysiloxane having at least 3 silicon-bonded hydrogen atoms per molecule; and

(C) 0.1 to 1,000 parts by weight of a platinum-containing catalyst, said weight being based on the parts by weight of platinum per one million parts by weight of the total of (A) and (B); and

(II) exposing the coating and the substrate to heat in an amount sufficient to cure the coating.

25. A cured coating prepared by:

(I) coating a curable silicone release coating composition on the surface of a substrate wherein the coating composition comprises;

(A'"'"') 100 parts by weight of an organosilicon compound having its unit formula selected from;

##STR15## wherein R is a monovalent hydrocarbon group having from 1 to 10 carbon atoms and free of aliphatic unsaturation, R¹ is a fluorine-containing monovalent organic group having from 6 to 16 carbon atoms and having at least 4 --CF₂ -- groups, R² is selected from hydrogen or R, R³ is an alkylene group having from 2 to 10 carbon atoms, a, b, c, and d are positive numbers, m has a value of 0 or 1, n is an integer having a value of 0 to 2, and wherein the organosilicon compound has a weight average molecular weight of at least 1,000 with the proviso that there is at least two silicon-bonded hydrogen groups per molecule;

(B'"'"') 0.3-40 parts by weight of an organopolysiloxane having at least 3 silicon-bonded alkenyl groups per molecule; and

(C'"'"') 0.1 to 1,000 parts by weight of a platinum-containing catalyst, said weight being based on the parts by weight of platinum per one million parts by weight of the total of (A'"'"') and (B'"'"'); and

(II) exposing the coating and the substrate to heat in an amount sufficient to cure the coating.