Silicone release coatings containing higher alkenyl functional siloxanes

Claim 2

A curable coating composition comprising: (A) a triorganosiloxane-endblocked polydiorganosiloxane polymer having a viscosity at 25°C of at least 25 centistokes, wherein 90 to 99.5 percent of all organic radicals are methyl, from 0.5 to 10 percent of all organic radicals are unsaturated radicals independently selected from the group consisting of the vinyl radical and higher alkenyl radicals represented by the formula ­-R(CH₂) m CH=CH₂ wherein R denotes -(CH₂) n - or ­-(CH₂) p CH=CH- and m has the value of 1, 2, or 3; n has the value of 3 or 6; and p has the value of 3, 4, or 5 , with the proviso that at least 50 mole percent of the unsaturated radicals are higher alkenyl radicals; (B) a catalytic amount of a metal, hydrosilylation catalyst; (C) a methylhydrogenpolysiloxane cross-linking agent, compatible with (A) and having an average of at least three silicon-bonded hydrogen atoms per molecule with the hydrogen radicals being bonded to separate silicon atoms; (D) an effective amount of an inhibitor for the metal, hydrosilylation catalyst; and wherein the composition contains 0.8 to 1.5 silicon-­bonded hydrogen radicals for every unsaturated radical in the composition.

Claim 3

A curable coating composition in accordance with claim 1 wherein (A) has a viscosity at 25°C of 100 to 1000 centistokes and the alkenyl radicals are selected from the group consisting of 5-hexenyl, 7-octenyl, 9-decenyl, and 5,9-decadienyl radicals.

Claim 4

A curable coating composition in accordance with claim 2 wherein (A) has a viscosity at 25°C of 200 to 600 centistokes and the alkenyl radical is the 5-hexenyl radical.

Claim 5

A process for preparing a laminate of a substrate and an adhesive wherein the adhesive will release from the substrate, the process comprising the steps of: (I) coating a curable silicone release composition on the surface of the substrate wherein the composition comprises (A) a triorganosiloxane-endblocked polydiorganosiloxane polymer having a viscosity at 25°C of at least 25 centistokes, wherein 90 to 99.5 percent of all organic radicals are methyl, from 0.5 to 10 percent of all organic radicals are unsaturated radicals independently selected from the group consisting of the vinyl radical and higher alkenyl radicals represented by the formula -R(CH₂) m CH=CH₂ wherein R denotes -(CH₂) n - or -(CH₂) p CH=CH- and m has the value of 1, 2, or 3; n has the value of 3 or 6; and p has the value of 3, 4, or 5, with the proviso that at least 50 mole percent of the unsaturated radicals are higher alkenyl radicals; (B) a catalytic amount of a metal, hydrosilylation catalyst; (C) a methylhydrogenpolysiloxane cross-linking agent, compatible with (A) and having an average of at least three silicon-bonded hydrogen atoms per molecule with the hydrogen radicals being bonded to separate silicon atoms; (D) an effective amount of an inhibitor for the metal, hydrosilylation catalyst; and wherein the composition contains 0.8 to 1.5 silicon-bonded hydrogen radicals for every unsaturated radical in the composition; (II) curing the silicone release composition with an effective amount of heat; (III) applying, on line, an adhesive to the silicone surface of the substrate.

Claim 6

A process for preparing a laminate of a substrate and an adhesive wherein the adhesive will release from the substrate, the process comprising the steps of: (I) coating a curable silicone release composition on the surface of the substrate wherein the composition comprises (A) a triorganosiloxane-endblocked polydiorganosiloxane polymer having a viscosity at 25°C of at least 25 centistokes, wherein 90 to 99.5 percent of all organic radicals are methyl, from 0.5 to 10 percent of all organic radicals are unsaturated radicals independently selected from the group consisting of the vinyl radical and higher alkenyl radicals represented by the formula -R(CH₂) m CH=CH₂ wherein R denotes -(CH₂) n - or -(CH₂) p CH=CH- and m has the value of 1, 2, or 3; n has the value of 3 or 6; and p has the value of 3, 4, or 5, with the proviso that at least 50 mole percent of the unsaturated radicals are higher alkenyl radicals; (B) a catalytic amount of a metal, hydrosilylation catalyst; (C) a methylhydrogenpolysiloxane cross-linking agent, compatible with (A) and having an average of at least three silicon-bonded hydrogen atoms per molecule with the hydrogen radicals being bonded to separate silicon atoms; (D) an effective amount of an inhibitor for the metal, hydrosilylation catalyst; and wherein the composition contains 0.8 to 1.5 silicon-bonded hydrogen radicals for every unsaturated radical in the composition; (II) curing the silicone release composition with an effective amount of heat; (III) applying, on line, an adhesive to the silicone surface of the substrate.

Claim 7

In a process for preparing a laminate of a substrate and adhesive wherein the adhesive will release from the substrate, the process comprising coating a curable silicone release composition on a surface of the substrate, thereafter curing the silicone composition, and applying an adhesive to the silicone surface of the substrate, the improvement comprising coating as the curable silicone release composition, a composition comprising (A) a triorganosiloxane-endblocked polydiorganosiloxane polymer having a viscosity at 25°C of at least 25 centistokes, wherein 90 to 99.5 percent of all organic radicals are methyl, from 0.5 to 10 percent of all organic radicals are unsaturated radicals independently selected from the group consisting of the vinyl radical and higher alkenyl radicals represented by the formula -R(CH₂) m CH=CH₂ wherein R denotes -(CH₂) n - or -(CH₂) p CH=CH- and m has the value of 1, 2, or 3; n has the value of 3 or 6; and p has the value of 3, 4, or 5, with the proviso that at least 50 mole percent of the unsaturated radicals are higher alkenyl radicals; (B) a catalytic amount of a metal, hydrosilylation catalyst; (C) a methylhydrogenpolysiloxane cross-linking agent, compatible with (A) and having an average of at least three silicon-bonded hydrogen atoms per molecule with the hydrogen radicals being bonded to separate silicon atoms; (D) an effective amount of an inhibitor for the metal, hydrosilylation catalyst; and wherein the composition contains 0.8 to 1.5 silicon-bonded hydrogen radicals for every unsaturated radical in the composition.

Claim 8

In a process for preparing a laminate of a substrate and adhesive wherein the adhesive will release from the substrate, the process comprising coating a curable silicone release composition on a surface of the substrate, thereafter curing the silicone composition, and applying an adhesive to the silicone surface of the substrate, the improvement comprising coating as the curable silicone release composition, a composition comprising (A) a triorganosiloxane-endblocked polydiorganosiloxane polymer having a viscosity at 25°C of at least 25 centistokes, wherein 90 to 99.5 percent of all organic radicals are methyl, from 0.5 to 10 percent of all organic radicals are unsaturated radicals independently selected from the group consisting of the vinyl radical and higher alkenyl radicals represented by the formula -R(CH₂) m CH=CH₂ wherein R denotes -(CH₂) n - or -(CH₂) p CH=CH- and m has the value of 1, 2, or 3; n has the value of 3 or 6; and p has the value of 3, 4, or 5, with the proviso that at least 50 mole percent of the unsaturated radicals are higher alkenyl radicals; (B) a catalytic amount of a metal, hydrosilylation catalyst; (C) a methylhydrogenpolysiloxane cross-linking agent, compatible with (A) and having an average of at least three silicon-bonded hydrogen atoms per molecule with the hydrogen radicals being bonded to separate silicon atoms; (D) an effective amount of an inhibitor for the metal, hydrosilylation catalyst; and wherein the composition contains 0.8 to 1.5 silicon-bonded hydrogen radicals for every unsaturated radical in the composition.