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US 5,292,787 AGranted
Epoxysilicone controlled release composition
AssigneeGeneral Electric Company
InventorsRoy M. Griswold, Michael J. O'Brien
Life of this patent
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Abstract
The invention provides a thermal and addition curable silicone release coating comprising a mixture of an epoxysilicone controlled release additive containing at least one tri- or quadri-functional siloxane unit, a vinyl-functional silicone base polymer, a temperature-dependent hydrosilation inhibitor and an effective hydrosilation catalyst.
Claims15
A curable organopolysiloxane composition comprising:
- (A) from about 1 to about 98% by weight of the curable composition of an epoxy-functional siloxane which functions as a release additive to control adhesion comprising unit(s) of the formula (I):
- R.sub.a R.sub.b.sup.1 SiO.sub.(4-a-b)/2 (I)
- and unit(s) of the formula (II);
- RSiO.sub.3/2 (II)
- where R is unsubstituted or substituted C.sub.(1-8) alkyl, R.sup.1 is a monovalent epoxy-functional organic radical of from about 2 to about 20 carbon atoms;
- a is 1, 2 or 3;
- b is 0, 1, 2 or 3;
- and a+b is 2 or 3;
- and with the provision that at least one unit of formula (I) contains the monovalent epoxy-functional radical per molecule;
- (B) from about 1 to about 98% by weight of the curable composition of a vinyl-functional siloxane of the general formula with the provision that at least 2 to about 6 units of the above formula are vinyl-functional:
- R.sub.c R.sub.d.sup.2 SiO.sub.(4-c-d)/2
- where R is as defined above, R.sup.2 is unsubstituted or substituted vinyl-functional C.sub.(1-8) alkenyl;
- c is 0, 1, 2 or 3;
- d is 0, 1, 2 or 3;
- d is 0, 1, 2 or 3;
- and c+d is 2 or 3.
- (C) an effective amount of a temperature-dependent hydrosilation addition reaction inhibitor;
- (D) an effective amount of a hydrosilation catalyst;
- and
- (E) from about 1 to about 10% by weight of the curable composition of an organopolysiloxane which functions as a crosslinker of the general formula:
- R.sub.e (H).sub.f SiO.sub.(4-e-f)/2
- where R is as defined in (A);
- e is 0, 1 or 2;
- f is 0, 1, 2 or 3;
- and e+f is 0, 1, 2 or 3 with the provision that sufficient SiH functional units such that the ratio of SiH units to the sum of vinyl and epoxy units of the curable composition is from about 0.8 to about 2.5.
22 more elements
A curable organopolysiloxane composition comprising:
- (A) from about 1 to about 98%, by weight of the curable composition of an epoxy-functional siloxane which functions as a release additive to control adhesion comprising unit(s) of the formula (I):
- R.sub.a R.sub.b.sup.1 SiO.sub.(4-a-b)/2
- and unit(s) of the formula (III);
- SiO.sub.4/2
- where R is unsubstituted or substituted C.sub.(1-8) alkyl, R.sup.1 is a monovalent epoxy-functional organic radical of from 2 to about 20 carbon atoms;
- a is 1, 2 or 3;
- b is 0, 1, 2 or 3;
- and a+b is 2 or 3;
- and with the provision that at least one unit of formula (I) contains the monovalent epoxy-functional radical per molecule;
- (B) from about 1 to about 98% by weight of the curable composition of a vinyl-functional siloxane which functions as a release compound's base composition with at least two to about 6 units of the formula:
- R.sub.c R.sub.d.sup.2 SiO.sub.(4-c-d)/2
- where R is as defined above, R.sup.2 is unsubstituted or substituted vinyl-functional C.sub.(1-8) alkenyl;
- c is 0, 1, 2 or 3;
- d is 0, 1, 2 or 3;
- and c+d is 2 or 3.
- (C) an effective amount of a temperature-dependent hydrosilation addition reaction inhibitor;
- (D) an effective amount of a hydrosilation catalyst;
- and
- (E) from about 1 to about 10% by weight of a curable composition an organopolysiloxane which functions as a crosslinker consisting essentially of units of the formula and combinations thereof:
- R.sub.e (H).sub.f SiO.sub.(4-a-b)/2
- where R is as defined in (A);
- e is 0, 1 or 2;
- f is 0, 1, 2 or 3 and e+f is 2 or 3.
20 more elements
Dependencies are inferred from the claim text.