Patent classifications
C08G77/44
Hydrophilic polysiloxane elastomer
An elastomer has the general structure of: ##STR00001##
where: subscript a is 50-500, b is 1-10, c is 2-30, R.sup.1 has the structure:
—CH.sub.2(CH.sub.2).sub.nO(CH.sub.2).sub.pCH(OH)(CH.sub.2).sub.qNR.sup.2R.sup.2′ where n, p and q are each independently 1-5 and R.sup.2 and R.sup.2′ are independently selected from alkyl and hydroxyalkyl groups having 1-5 carbon atoms; where X is a crosslinker remnant bound to a siloxane unit corresponding to subscript c of a siloxane backbone polymer in addition to the one shown so that the crosslinker remnant in each occurrence is a reaction product with two siloxane backbone polymers, wherein the crosslinker is selected from a group consisting of primary organic dienes, divinyl siloxane and polyoxyalkylenes wherein at least two X components correspond to crosslinker remnants connecting the same two siloxane backbone polymers.
Silicone resin liquid composition
A silicone resin liquid composition containing a silicone resin is provided. The .sup.29Si-NMR measurement of the resin exhibits a ratio of the area of signals assigned to A3 silicon atoms to the area of all signals derived from silicon atoms of 51% to 69%. An A3 silicon atom represents a silicon atom to which are bonded three oxygen atoms bonded to another silicon atom.
Silicone resin liquid composition
A silicone resin liquid composition containing a silicone resin is provided. The .sup.29Si-NMR measurement of the resin exhibits a ratio of the area of signals assigned to A3 silicon atoms to the area of all signals derived from silicon atoms of 51% to 69%. An A3 silicon atom represents a silicon atom to which are bonded three oxygen atoms bonded to another silicon atom.
NOVEL SILICONE COMPOSITION CROSSLINKING CATALYSTS
A crosslinked silicone material Y obtained by heating to a temperature of between 70 and 200° C., a crosslinkable composition X including an organopolysiloxane compound A containing, per molecule, at least two C.sub.2-C.sub.6 alkenyl radicals bonded to silicon atoms; an organohydrogenopolysiloxane compound B containing, per molecule, at least two hydrogen atoms bonded to an identical or different silicon atom; a catalyst C of formula [Ni(L.sup.1).sub.2] where Ni represents nickel at degree of oxidation II; L.sup.1 which may be identical or different, represents a β-dicarbonylato anion or the enolate anion of a β-dicarbonylated compound; optionally an adhesion promoter D; and optionally a charge E.
NOVEL SILICONE COMPOSITION CROSSLINKING CATALYSTS
A crosslinked silicone material Y obtained by heating to a temperature of between 70 and 200° C., a crosslinkable composition X including an organopolysiloxane compound A containing, per molecule, at least two C.sub.2-C.sub.6 alkenyl radicals bonded to silicon atoms; an organohydrogenopolysiloxane compound B containing, per molecule, at least two hydrogen atoms bonded to an identical or different silicon atom; a catalyst C of formula [Ni(L.sup.1).sub.2] where Ni represents nickel at degree of oxidation II; L.sup.1 which may be identical or different, represents a β-dicarbonylato anion or the enolate anion of a β-dicarbonylated compound; optionally an adhesion promoter D; and optionally a charge E.
Method for making contact lenses
The instant invention pertains to a method and a fluid composition for producing contact lenses with improved lens quality and with increased product yield. The method of the invention involves applying to a molding surface of the mold a layer of mold releasing agent selected from a group consisting of fatty amines of carbon chain length C18 or less and silicones bearing pendant substituted pyrrolidone groups solution to reduce an averaged mold separation force by at least about 50% in comparison with that without the releasing agent.
Method for making contact lenses
The instant invention pertains to a method and a fluid composition for producing contact lenses with improved lens quality and with increased product yield. The method of the invention involves applying to a molding surface of the mold a layer of mold releasing agent selected from a group consisting of fatty amines of carbon chain length C18 or less and silicones bearing pendant substituted pyrrolidone groups solution to reduce an averaged mold separation force by at least about 50% in comparison with that without the releasing agent.
MULTICOMPONENT ROOM TEMPERATURE-CURABLE ORGANOPOLYSILOXANE COMPOSITION, CURED PRODUCT OF SAID COMPOSITION, AND MOLDED PRODUCT COMPRISING SAID CURED PRODUCT
Provided is a multicomponent room temperature-curable organopolysiloxane composition capable of providing a cured product superior in fast curability, storage stability and durability. The room temperature-curable organopolysiloxane composition comprises: (A) an alkoxysilyl-ethylene group-terminated organopolysiloxane having in each molecule at least one silyl-ethylene bond represented by the following structural formula (1)
##STR00001##
(wherein R.sup.1 represents an alkyl group; R.sup.2 represents a hydrocarbon group having 1 to 20 carbon atoms; a represents an integer of 1 to 3; and n represents an integer of 0 to 10); (B) an organopolysiloxane represented by the following general formula (2)
##STR00002## (wherein R.sup.2 represents a hydrocarbon group having 1 to 20 carbon atoms; and m represents a number at which such organopolysiloxane exhibits a viscosity of 10 to 1,000,000 mPa.Math.s at 25° C.); and (C) a curing catalyst.
ADHESIVE COMPOSITIONS AND USES THEREOF
Adhesive compositions are disclosed. In some embodiments, the adhesive compositions comprise an organosiloxane block copolymer, wherein the blocks of the block copolymer consist of an —Si—O—Si— backbone. The organosiloxane block copolymer comprises at least two blocks that are phase-separated. The organosiloxane block copolymer has at least a first glass transition temperature (Tg.sup.1) and a second glass transition temperature (Tg.sup.2), the second glass transition temperature being at 25° C. or higher. A 1 mm thick cast film of the adhesive composition has, in some embodiments, a light transmittance of at least 95%. The adhesive composition of the various embodiments of the present invention can be B-staged at about Tg.sup.2 or at about 100° C. below Tg.sup.2.
ADHESIVE COMPOSITIONS AND USES THEREOF
Adhesive compositions are disclosed. In some embodiments, the adhesive compositions comprise an organosiloxane block copolymer, wherein the blocks of the block copolymer consist of an —Si—O—Si— backbone. The organosiloxane block copolymer comprises at least two blocks that are phase-separated. The organosiloxane block copolymer has at least a first glass transition temperature (Tg.sup.1) and a second glass transition temperature (Tg.sup.2), the second glass transition temperature being at 25° C. or higher. A 1 mm thick cast film of the adhesive composition has, in some embodiments, a light transmittance of at least 95%. The adhesive composition of the various embodiments of the present invention can be B-staged at about Tg.sup.2 or at about 100° C. below Tg.sup.2.