Fast ultraviolet radiation curing silicone composition

Claim 2

A composition comprising a material which is storable in one package, is viscosity stable indicated by the failure of the 25° C. viscosity to double when heated at 100° C. for 24 hours, cures when exposed to ultraviolet radiation of 70 millijoules or less per square cectimeter in one second or less where the ultraviolet radiation includes a wavelength of 365 nanometers, and is obtained by mixing (A) alkenyl functional, linear triorganosiloxy endblocked polydiorganosiloxane having a degree of polymerization of 30 to 1,000 where each silicon-bonded organic radical is selected from the group consisting of vinyl, methyl, phenyl, 3,3,3-trifluoropropyl, beta-(cyclohexenyl)ethyl, ethyl, cyclohexenyl, allyl, higher alkenyl radicals represented by the formula --R*(CH 2 ) r CH═C.H 2 wherein R* is --(CH 2 )-- or --(CH 2 ) t Ch═CH--, r has a value of 1,2, or 3; s has a value of 3 or 6; and t has a value of 3, 4, or 5, and silacyclopentenyl, and having per molecule at least two silicon-bonded organic radicals selected from the group consisting of vinyl, beta-(cyclohexenyl)ethyl, cyclohexenyl, allyl, higher alkenyl radical, and silacyclopentenyl, (B) mercapto functional crosslinker which is at least one material selected from the group consisting of mercapto functional polyorganosiloxanes and mercapto organic compounds, said mercapto functional polyorganosiloxanes are represented by the general formula R"R'.sub.2 SiO(R'"R'SiO).sub.x (R'RSiO).sub.y SiR'.sub.2 R" wherein each R is selected from the group consisting of mercaptoalkyl radicals having from 2 to 6 carbon atoms per radical; each R' is selected from the the group consisting of methyl, phenyl, 3,3,3-trifluoropropyl, and ethyl; and each R" is a radical selected from the group consisting of --OH, R, and R'; and each R'" is methyl or phenyl, on the average there being per molecule at least two mercaptoalkyl radicals, x is 0 or greater, y is 0 or greater, and the amount and kind of organic radicals represented by R, R', R", and R'" being of such a nature as to make (A) and (B) compatible, and said mercapto organic compounds have at least two mercapto groups per molecule, consisting of atoms of sulfur, carbon, and hydrogen, and optionally oxygen, having molecular weight less than 1,000, and being of such a nature as to make (A) and (B) compatible, (C) photosensitizer, (D) an amine storage stabilizer, and (E) reinforcing agent, there being in said material from 0.5 to 1.5 total alkenyl radicals per mercapto group.

Claim 3

The composition according to claim 1 in which (A) is a polydiorganosiloxane represented by the formula CH.sub.2 ═CH(CH.sub.3).sub.2 SiO{(CH.sub.3).sub.2 SiO}.sub.m --{(CH.sub.2 ═CH) (CH.sub.3)SiO}.sub.n Si(CH.sub.3).sub.2 CH═C.H.sub.2 wherein m has an average value of from 80 to 500 and n has an average value of from 0 to 10 inclusive, (B) is a mercapto functional polyorganosiloxane of the average formula (CH.sub.3).sub.3 SiO({(CH.sub.3).sub.2 SiO}.sub.w {R(CH.sub.3)SiO}).sub.z Si(CH.sub.3).sub.3 wherein R is gamma-mercaptopropyl or mercaptoisobutyl, w has an average value of from 3 to 12, and z has an average value of from 2 to 8, and the photosensitizer of (C) is present in an amount of from 1 to 4 weight percent based on the total weight of the composition and is 2,2-diethoxyacetophenone or ##STR24## there being in said material from 0.57 to 1.25 vinyl radical per mercapto group.

Claim 4

The composition according to claim 1 in which reinforcing agent is present in an amount of at least five weight percent based on the total weight of the composition, said reinforcing agent not substantially increasing the opacity of the composition compared to the composition without the reinforcing agent.

Claim 5

The composition according to claim 3 in which the reinforcing agent is also non-abrasive to a glass surface.

Claim 6

The composition according to claim 2 in which the storage stabilizer of (D) is an amine which does not increase the opacity of the composition compared to the composition without the amine.

Claim 7

The composition according to claim 5 in which the amine is present in an amount of from 0.5 to 1.5 weight percent based on the total weight of the composition, and the amine is trioctylamine or 2-(diisopropylamino)ethanol.

Claim 8

The composition according to claim 2 in which the reinforcing agent is a siloxane resin.

Claim 9

The composition according to claim 7 in which the reinforcing agent is present in an amount of from 23 to 37.5 percent by weight based on the total weight of the composition and the reinforcing agent is a benzene soluble silicone resin containing trimethylsiloxy units, dimethylvinylsiloxy units, and SiO 2 units where the ratio of moles of trimethylsiloxy units plus moles of dimethylvinylsiloxy units to moles of SiO 2 units is 0.5:1 to 1.1:1, and the resin contains 1.7 to 2.0 weight percent vinyl radical based on the weight of the resin.

Claim 10

The composition according to claim 5 in which the reinforcing agent is a siloxane resin.

Claim 11

The composition according to claim 9 in which the reinforcing agent is present in an amount of from 23 to 37.5 percent by weight based on the total weight of the composition and the reinforcing agent is a benzene soluble silicone resin containing trimethylsiloxy units, dimethylvinylsiloxy units, and SiO 2 units where the ratio of moles of trimethylsiloxy units plus moles of dimethylvinylsiloxy units to moles of SiO 2 units is 0.5:1 to 1.1:1, and the resin contains 1.7 to 2.0 weight percent vinyl radical based on the weight of the resin.

Claim 12

The composition according to claim 1 in which the refractive index at 25° C. is less than 1.45.

Claim 13

The composition according to claim 2 in which the refractive index at 25° C. is less than 1.45.

Claim 14

The composition according to claim 6 in which the refractive index at 25° C. is less than 1.45.

Claim 15

The composition according to claim 1 in which (E) is present in an amount of at least five weight percent and is a fumed silica.

Claim 16

The compositon according to claim 1 in which there are at least two higher alkenyl radicals per molecule in (A).

Claim 17

The composition according to claim 2 in which there are at least two higher alkenyl radicals per molecule in (A).

Claim 18

The composition according to claim 2 in which there are at least two higher alkenyl radicals per molecule in (A).

Claim 19

A composition comprising a material which is storable in one package, is viscosity stable indicated by the failure of the 25° C. viscosity to double when heated at 100° C. for 24 hours, cures when exposed to ultraviolet radiation of 70 millijoules or less per square centimeter in one second or less where the ultraviolet radiation includes a wavelength of 365 nanometers, and is obtained by mixing (A) alkenyl functional, linear triorganosiloxy endblocked polydiorganosiloxane having a degree of polymerization of 30 to 1,000 where each silicon-bonded organic radical selected from the group consisting of vinyl, methyl, phenyl, 3,3,3 trifluoropropyl, beta-(cyclohexenyl)ethyl, ethyl, cyclohexenyl, allyl, higher alkenyl radicals represented by the formula --R*(CH 2 ) r CH═CH 2 wherein R* is --(CH 2 ) s --or--(CH 2 ) t CH═CH--, r has a value of 1,2, or 3; s has a value of 3 or 6; and t has a value of 3, 4, or 5, and silacyclopentenyl, and having per molecule at least two silicon-bonded organic radicals selected from the group consisting of vinyl, beta-)cyclohexenyl)ethyl, cyclohexenyl, allyl, higher alkenyl radical and silacyclopentenyl, (B) mercapto functional crosslinker is mercapto organic compound having at least two mercapto groups per molecule, consisting of atoms of sulfur, carbon, and hydrogen, and optionally oxygen, having a molecular weight less than 1,000, and being of such a nature as to make (A) and (B) compatible, (C) photosensitizer, (D) storage stabilizer, and (E) reinforcing agent, there being in said material from 0.5 to 1.5 total alkenyl radicals per mercapto group.

Claim 20

A composition comprising a material which is storable in one package, is viscosity stable indicated by the failure of the 25° C. viscosity to double when heated at 100° C. for 24 hours, cures when exposed to ultraviolet radiation of 70 millijoules or less per square centimeter in one second or less where the ultraviolet radiation includes a wavelength of 365 nanometers, and is obtained by mixing (A) alkenyl functional, linear triorganosiloxy endblocked polydiorganosiloxane having a degree of polymerization of 30 to 1,000 where each silicon-bonded organic radical selected from the group consisting of vinyl, methyl, phenyl, 3,3,3 trifluoropropyl, beta-(cyclohexenyl)ethyl, ethyl, cyclohexenyl, allyl, higher alkenyl radicals represented by the formula --R*(CH 2 ) r CH═CH 2 wherein R* is --(CH 2 ) s --or--(CH 2 ) t CH═CH--, r has a value of 1,2, or 3; s has a value of 3 or 6; and t has a value of 3, 4, or 5, and silacyclopentenyl, and having per molecule at least two silicon-bonded organic radicals selected from the group consisting of vinyl, beta-)cyclohexenyl)ethyl, cyclohexenyl, allyl, higher alkenyl radical and silacyclopentenyl, (B) mercapto functional crosslinker is mercapto organic compound having at least two mercapto groups per molecule, consisting of atoms of sulfur, carbon, and hydrogen, and optionally oxygen, having a molecular weight less than 1,000, and being of such a nature as to make (A) and (B) compatible, (C) photosensitizer, (D) storage stabilizer, and (E) reinforcing agent, there being in said material from 0.5 to 1.5 total alkenyl radicals per mercapto group.

Claim 21

The composition according to claim 18 in which (A) is a dimethylvinylsiloxy endblocked polydiorganosiloxane containing siloxane units selected from the group consisting of dimethylsiloxane, methylphenylsiloxane, and diphenylsiloxane where at least 30 percent of the organic radicals on silicon being phenyl, (B) is selected from the group consisting of CH.sub.3 C(CH.sub.2 OOCCH.sub.2 SH).sub.3, {(HSCH.sub.2 CH.sub.2 COOCH.sub.2).sub.3 CCH.sub.2 }.sub.2 O, C(CH.sub.2 OOCCH.sub.2 CH.sub.2 SH).sub.4, C(CH.sub.2 OOCCH.sub.2 SH).sub.4, CH.sub.3 C(CH.sub.2 OOCCH.sub.2 CH.sub.2 SH).sub.3, CH.sub.3 CH.sub.2 C(CH.sub.2 OOCCH.sub.2 CH.sub.2 SH).sub.3, and CH.sub.3 CH.sub.2 C(CH.sub.2 OOCCH.sub.2 SH).sub.3 and the photosensitizer of (C) is present in an amount of from 1 to 4 weight percent based on the total weight of the composition and is 2,2-diethoxyacetophenone or ##STR25##

Claim 22

The composition according to claim 19 in which the refractive index at 25° C. is greater than 1.48.

Claim 23

A composition comprising a material which is storable in one package, is viscosity stable indicated by the failure of the 25° C. viscosity to double when heated at 100° C. for 24 hours, cures when exposed to ultraviolet radiation of 70 millijoules or less per square centimeter in one second or less where the ultraviolet radiation includes a wavelength of 365 nanometers, and is obtained by mixing (A) alkenyl functional, linear triorganosiloxy endblocked polydiogranosiloxane having a degree of polymerization of 30 to 1,000 where each silicon-bonded organic radical is selected from the group consisting of vinyl, methyl, phenyl, 3,3,3-trifluoropropyl, beta-(cyclohexenyl)ethyl, ethyl, cyclohenxenyl, allyl, silacyclopentenyl, and higher alkenyl radicals represented by the formula -R*(CH 2 ) r CH═CH 2 wherein R* is --(CH 2 ) s --or --(CH 2 ) t CH═CH--, r has a value of 1, 2, or 3; s has a value of 3 or 6; to has a value of 3, 4 or 5, and having per molecule at least two silicon-bonded organic radicals selected from the group consisting of vinyl, beta-(cyclohexenyl)ethyl, cyclohexenyl, allyl, higher alkenyl radical, and silacyclopentenyl, (B) mercapto functional crosslinker which is at least one material selected from the group consisting of mercapto functional polyorganosiloxanes and mercapto functional organic oompounds, said mercapto functional polyorganosiloxanes are represented by the general formula R"R'.sub.2 SiO(R'"R'SiO).sub.x (R'RSiO).sub.y SiR'.sub.2 R" wherein each R is selected from mercaptoalkyl radicals having from 2 to 6 carbon atoms per radical; each R', is selected from the group consisting of methyl, phenyl, 3,3,3-trifluoropropyl, and ethyl; and each R" is a radical selected from the group consisting of--OH, R, and R'; and each R"' is methyl or phenyl, on the average there being per molecule at least two mercaptoalkyl radicals, x is 0 or greater, y is 0 or greater, and the amount and kind of organic radicals represented by R, R', R", and R"' being of such a nature as to make (A) and (B) compatible, and said mercapto organic compounds have at least two mercapto groups per molecule, consisting of atoms of sulfur, carbon, and hydrogen, and optionally oxygen, having a molecular weight less than 1,000, and being of such a nature as to make (A) and (B) compatible, (C) compabible photosensitizer selected from the group consisting of benzophenone, acetophenone, benzoin methylether, benzoin isobutylether, 2,2-diethoxyacetophenone, ##STR26## (D) an amine viscosity stabilizer, and (E) reinforcing agent, therein being in said material from 0.5 to 1.5 total alkenyl radicals per mercapto group.

Claim 24

A composition comprising a material which is storable in one package, is viscosity stable indicated by the failure of the 25° C. viscosity to double when heated at 100° C. for 24 hours, cures when exposed to ultraviolet radiation of 70 millijoules or less per square centimeter in one second or less where the ultraviolet radiation includes a wavelength of 365 nanometers, and is obtained by mixing (A) alkenyl functional, linear triorganosiloxy endblocked polydiogranosiloxane having a degree of polymerization of 30 to 1,000 where each silicon-bonded organic radical is selected from the group consisting of vinyl, methyl, phenyl, 3,3,3-trifluoropropyl, beta-(cyclohexenyl)ethyl, ethyl, cyclohenxenyl, allyl, silacyclopentenyl, and higher alkenyl radicals represented by the formula -R*(CH 2 ) r CH═CH 2 wherein R* is --(CH 2 ) s --or --(CH 2 ) t CH═CH--, r has a value of 1, 2, or 3; s has a value of 3 or 6; to has a value of 3, 4 or 5, and having per molecule at least two silicon-bonded organic radicals selected from the group consisting of vinyl, beta-(cyclohexenyl)ethyl, cyclohexenyl, allyl, higher alkenyl radical, and silacyclopentenyl, (B) mercapto functional crosslinker which is at least one material selected from the group consisting of mercapto functional polyorganosiloxanes and mercapto functional organic oompounds, said mercapto functional polyorganosiloxanes are represented by the general formula R"R'.sub.2 SiO(R'"R'SiO).sub.x (R'RSiO).sub.y SiR'.sub.2 R" wherein each R is selected from mercaptoalkyl radicals having from 2 to 6 carbon atoms per radical; each R', is selected from the group consisting of methyl, phenyl, 3,3,3-trifluoropropyl, and ethyl; and each R" is a radical selected from the group consisting of--OH, R, and R'; and each R"' is methyl or phenyl, on the average there being per molecule at least two mercaptoalkyl radicals, x is 0 or greater, y is 0 or greater, and the amount and kind of organic radicals represented by R, R', R", and R"' being of such a nature as to make (A) and (B) compatible, and said mercapto organic compounds have at least two mercapto groups per molecule, consisting of atoms of sulfur, carbon, and hydrogen, and optionally oxygen, having a molecular weight less than 1,000, and being of such a nature as to make (A) and (B) compatible, (C) compabible photosensitizer selected from the group consisting of benzophenone, acetophenone, benzoin methylether, benzoin isobutylether, 2,2-diethoxyacetophenone, ##STR26## (D) an amine viscosity stabilizer, and (E) reinforcing agent, therein being in said material from 0.5 to 1.5 total alkenyl radicals per mercapto group.

Claim 25

The composition according to claim 21 in which (A) is a polydiorganosiloxane represented by the formula CH.sub.2 ═CH(CH.sub.3).sub.2 SiO{(CH.sub.3).sub.2 SiO}.sub.m {(CH.sub.2═CH) (CH.sub.3)SiO}.sub.n Si(CH.sub.3).sub.2 CH═CH.sub.2 wherein m has an average value of from 80 to 500 and n has an average value of from 0 to 10 inclusive, (B) is a mercapto functional polyorganosiloxane of the average formula (CH.sub.3).sub.3 SiO({(CH.sub.3).sub.2 SiO}.sub.w {R(CH.sub.3)SiO}).sub.z Si(CH.sub.3).sub.3 wherein R is gamma-mercaptopropyl or mercaptoisobutyl, w has an average value of 3 to 12, and z has an average value of from 2 to 8, and the photosensitizer of (C) is present in an amount of from 1 to 4 weight percent based on the total weight of the composition and is 2,2-diethoxyacetophenone, and there being in said material from 0.57 to 1.25 vinyl radical per mercapto group.

Claim 26

The composition according to claim 21 in which (A) is polydiorganosiloxane represented by the formula CH.sub.2 ═CH(CH.sub.3).sub.2 SiO{(CH.sub.3).sub.2 SiO}.sub.m {(CH.sub.2 ═CH)(CH.sub.3)SiO}.sub.n Si(CH.sub.3) .sub.2 CH═CH.sub.2 wherein m has an average value of from 80 to 500 and n has an average value of from 0 to 10 inclusive, (B) is a mercapto functional polyorganosiloxane of the average formula (CH.sub.3).sub.3 SiO({(CH.sub.3).sub.2 SiO}.sub.w {R(CH.sub.3)SiO}).sub.z Si(CH.sub.3).sub.3 wherein R is gamma-mercaptopropyl or mercaptiosobutyl, w has an average value of 3 to 12, and z has an average value of from 2 to 8, and the photosensitizer of (C) is present in an amount of from 1 to 4 weight percent based on the total weight of the composition and is ##STR27## and there being in said material from 0.57 to 1.25 vinyl radical per mercapto group.

Claim 27

The composition according to claim 21 in which reinforcing agent is present in an amount of at least five weight based on the total weight of the composition, said reinforcing agent into substantially increasing the opacity of the compositon compared to the composition without the reinforcing agent.

Claim 28

The composition according to claim 24 in which the reinforcing agent is also non-abrasive to a glass surface.

Claim 29

The composition according to claim 22 in which the viscosity stabilizer of (D) is an amine which does not increase the opacity of the composition compared to the composition without the amine.

Claim 30

The composition according to claim 23 in which the viscosity stabilizer of (D) is an amine which does not increase the opacity of the composition compared to the composition without the amine.

Claim 31

The composition according to claim 26 in which the amine is present in an amount of from 0.5 to 1.5 weight percent based on the total weight of the composition, and the amine is trioctylamine or 2-(diisopropylamino)ethanl.

Claim 32

The composition according to claim 27, in which the amine is present in an amount of from 0.5 to 1.5 weight percent based on the total weight of the composition, and the amine is trioctylamine or 2-(diisopropylamino)ethanol.

Claim 33

The composition according to claim 22 in which the reinforcing agent is a siloxane resin.

Claim 34

The composition according to claim 30 in which the reinforcing agent is present in an amount of from 23 to 37.5 percent by weight based on the total weight of the composition and the reinforcing agent is a benzene soluble silicone resin containing trimethylsiloxy units, dimethylvinylsiloxy units, and SiO 2 units where the ratio of moles of trimethylsiloxy units plus moles of dimethylvinylsiloxy units to moles of SiO 2 units is 0.5:1 to 1.1:1, and the resin contains 1.7 to 2.0 weight percent vinyl percent radical based on the weight of the resin.

Claim 35

The composition according to claim in which the reinforcing agent is a siloxane resin.

Claim 36

The composition according to claim 32 in which the reinforcing agent is present in an amount of from 23 to 37.5 percent by weight based on the total weight of the composition and the reinforcing agent is a benzene soluble silicone resin containing trimethylsiloxy units, dimethylvinylsiloxy units, and SiO 2 units where the ratio of moles of trimethylsiloxy units plus moles of dimethylvinylsiloxy units to moles of SiO 2 units is 0.5:1 to 1.1:1, and the resin contains 1.7 to 2.0 weight percent vinyl radical based on the weight of the resin.

Claim 37

The composition according to claim 21 in which (E) is present in an amount of at least five weight percent and is fumed silica.

Claim 38

The composition according to claim 21 in which here are at least two higher alkenyl radicals per molecule in (A).

Claim 39

The composition according to claim 1 in which (A) is dimethylvinylsiloxy endblocked polydimethylsiloxane having a viscosity at 25° C. of about 2 Pa.s, (B) is mercapto functional polyorganosiloxane of the average formula ##STR28## (C) is the photoinitiator of the formula ##STR29## (D) is present and is 2-(diisopropylamino)ethanol, and (D) is present and is a benzene soluble resin containing dimethylvinylsiloxy units, trimethylsiloxy units, and SiO 2 units where the ratio of the sum of the mols of dimethylvinylsiloxy units and trimethylsiloxy units to SiO 2 units is 0.65:1 and there is 1.9 weight percent vinyl radical in said resin.