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US4587137A Expired / Lapsed US ⏱️ 0.0 years remaining

Novel dual cure silicone compositions

Assignee: General Electric Co
•
Filing: 1985-09-19
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Granted: 1986-05-06
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Expires: 2005-09-19
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Abstract

Abstract There is provided a method for making curable compositions containing silicon-bonded hydrogen atoms and silicon-bonded olefinic radicals, the improvement comprising adding at least one free radical type photoinitiator and at least one precious metal or precious metal-containing hydrosilation catalyst so that crosslinking is effected by two separate mechanisms. The curable compositions and articles made therefrom are also provided.

Inventors

  • 👤 Richard P. Eckberg

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 13:03
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/14; H; H05; H05K; H05K3/00; H05K3/22; H05K3/28; H05K3/285; H05K3/287; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31652; Y10T428/31663

Claims Analysis

Total Claims: 55
Claim 1
Independent Claim 61 words
A curable composition comprising a polydiorganosiloxane containing silicon-bonded hydrogen atoms and silicon-bonded olefinic radicals in the same molecule, at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator and at least one precious metal-containing hydrosilation catalyst for effecting crosslinking of said silicon-bonded hydrogen atoms and said silicon bonded olefinic radicals.
Claim 2
Dependent Claim 61 words
A curable composition comprising a polydiorganosiloxane containing silicon-bonded hydrogen atoms and silicon-bonded olefinic radicals in the same molecule, at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator and at least one precious metal-containing hydrosilation catalyst for effecting crosslinking of said silicon-bonded hydrogen atoms and said silicon bonded olefinic radicals.
Claim 3
Dependent Claim 155 words
A curable composition comprising: (A) a polysiloxane having the general formula: ##STR12## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent alkenyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 centipoise to about 2,500,000 centipoise at 25° C.; (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst.
Claim 4
Dependent Claim 155 words
A curable composition comprising: (A) a polysiloxane having the general formula: ##STR12## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent alkenyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 centipoise to about 2,500,000 centipoise at 25° C.; (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst.
Claim 5
Dependent Claim 21 words
The composition of claim 2 wherein substantially all of the R radicals are methyl or a mixture of methyl and phenyl.
Claim 6
Dependent Claim 10 words
The composition of claim 2 wherein R 2 is vinyl.
Claim 7
Dependent Claim 70 words
The composition of claim 2 wherein x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of polysiloxane (A) is from about 100 centipoise to about 10,000 centipoise at 25° C.
Claim 8
Dependent Claim 40 words
The composition of claims 1 or 2 wherein the free radical photoinitiator has the general formula: ##STR13## where R 3 is a monovalent alkyl or aryl group or a halogen and Z is hydrogen, alkyl, halogen, nitro, amino or amido.
Claim 9
Dependent Claim 23 words
The composition of claim 6 wherein the free radical photoinitiator is selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and t-butylper-p-chlorobenzoate.
Claim 10
Dependent Claim 12 words
The composition of claim 7 wherein the free radical photoinitiator is t-butylperbenzoate.
Claim 11
Dependent Claim 43 words
The composition of claim 6 wherein the photoinitiator further comprises a sensitizer which is a polyaromatic compound possessing a ##STR14## chromophore, where pH is phenyl, and having at least two benzene rings which may be fused or bridged by organic radicals or hetero-radicals.
Claim 12
Dependent Claim 10 words
The composition of claim 9 wherein the photosensitizer is t-butylanthrquinone.
Claim 13
Dependent Claim 29 words
The composition of claims 1 or 2 wherein the precious metal-containing hydrosilation catalyst is selected from the group consisting of platinum metal, platinum complexes, rhodium metal and rhodium complexes.
Claim 14
Dependent Claim 58 words
The composition of claim 2 wherein the free radical photoinitiator is present in an amount of from about 1 to about 10 parts by weight per 100 parts by weight polysiloxane (A) and the precious metal-containing catalyst is present in an amount of from about 10 ppm to about 500 ppm as precious metal based on polysiloxane (A).
Claim 15
Dependent Claim 9 words
The composition of claim 2 further comprising an organohydrogenpolysiloxane.
Claim 16
Dependent Claim 10 words
The composition of claim 2 further comprising a vinyl-containing polysiloxane.
Claim 17
Dependent Claim 13 words
The composition of claim 2 further comprising an organohydrogenpolysiloxane and a vinyl-containing polysiloxane.
Claim 18
Dependent Claim 25 words
The composition of claim 2 or 15 further comprising an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 19
Dependent Claim 187 words
A curable composition comprising: (A) a polysiloxane having the general formula: ##STR15## where R is substantially all methyl radicals or a mixture of methyl and phenyl radicals; R 1 is selected from the group consisting of hydrogen atoms, hydroxyl radicals, methyl radicals and methoxy radicals; R 2 is a vinyl radical; x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane varies from about 100 centipoise to about 10,000 centipoise at 25° C.; (B) from 1 to 10 parts by weight per 100 parts by weight (A) of a photoinitiator selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and chlorobenzoate; (C) from 10 ppm to 500 ppm based on (A) of a platinum-containing hydrosilation catalyst, as platinum metal; (D) an organohydrogenpolysiloxane; (E) a vinyl-containing polydiorganosiloxane; and (F) an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 20
Dependent Claim 187 words
A curable composition comprising: (A) a polysiloxane having the general formula: ##STR15## where R is substantially all methyl radicals or a mixture of methyl and phenyl radicals; R 1 is selected from the group consisting of hydrogen atoms, hydroxyl radicals, methyl radicals and methoxy radicals; R 2 is a vinyl radical; x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane varies from about 100 centipoise to about 10,000 centipoise at 25° C.; (B) from 1 to 10 parts by weight per 100 parts by weight (A) of a photoinitiator selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and chlorobenzoate; (C) from 10 ppm to 500 ppm based on (A) of a platinum-containing hydrosilation catalyst, as platinum metal; (D) an organohydrogenpolysiloxane; (E) a vinyl-containing polydiorganosiloxane; and (F) an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 21
Independent Claim 65 words
A method for making a curable composition comprising mixing a polydiorganosiloxane containing silicon-bonded hydrogen atoms and silicon-bonded olefinic radicals in the same molecule, at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator and at least one precious metal-containing hydrosilation catalyst for effecting crosslinking of said silicon-bonded hydrogen atoms and said silicon-bonded olefinic radicals.
Claim 22
Independent Claim 65 words
A method for making a curable composition comprising mixing a polydiorganosiloxane containing silicon-bonded hydrogen atoms and silicon-bonded olefinic radicals in the same molecule, at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator and at least one precious metal-containing hydrosilation catalyst for effecting crosslinking of said silicon-bonded hydrogen atoms and said silicon-bonded olefinic radicals.
Claim 23
Independent Claim 160 words
A method for making a curable composition comprising mixing (A) a polysiloxane having the general formula: ##STR16## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent alkenyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 centipoise to about 2,500,000 centipoise at 25° C. (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst.
Claim 24
Independent Claim 160 words
A method for making a curable composition comprising mixing (A) a polysiloxane having the general formula: ##STR16## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent alkenyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 centipoise to about 2,500,000 centipoise at 25° C. (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst.
Claim 25
Dependent Claim 21 words
The method of claim 19 wherein substantially all of the R radicals are methyl or a mixture of methyl and phenyl.
Claim 26
Dependent Claim 10 words
The method of claim 19 wherein R 2 is vinyl.
Claim 27
Dependent Claim 70 words
The method of claim 19 wherein x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of polysiloxane (A) is from about 100 centipoise to about 10,000 centipoise at 25° C.
Claim 28
Independent Claim 40 words
The method of claims 18 or 19 wherein the free radical photoinitiator has the general formula: ##STR17## where R 3 is a monovalent alkyl or aryl group or a halogen and Z is hydrogen, alkyl, halogen, nitro, amino or amido.
Claim 29
Dependent Claim 23 words
The method of claim 23 wherein the free radical photoinitiator is selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and chlorobenzoate.
Claim 30
Dependent Claim 12 words
The method of claim 24 wherein the free radical photoinitiator is t-butylperbenzoate.
Claim 31
Dependent Claim 43 words
The method of claim 23 wherein the photoinitiator further comprises a sensitizer which is a polyaromatic compound possessing a ##STR18## chromophore, where Ph is phenyl, and having at least two benzene rings which may be fused or bridged by organic radicals or hetero-radicals.
Claim 32
Dependent Claim 10 words
The method of claim 26 wherein the photosensitizer is t-butylanthraquinone.
Claim 33
Independent Claim 29 words
The method of claims 18 or 19 wherein the precious metal-containing hydrosilation catalyst is selected from the group consisting of platinum metal, platinum complexes, rhodium metal and rhodium complexes.
Claim 34
Dependent Claim 58 words
The method of claim 19 wherein the free radical photoinitiator is present in an amount of from about 1 to about 10 parts by weight per 100 parts by weight polysiloxane (A) and the precious metal-containing catalyst is present in an amount of from about 10 ppm to about 500 ppm as precious metal based on polysiloxane (A).
Claim 35
Dependent Claim 10 words
The method of claim 19 further comprising mixing an organohydrogenpolysiloxane.
Claim 36
Dependent Claim 11 words
The method of claim 19 further comprising mixing a vinyl-containing polysiloxane.
Claim 37
Dependent Claim 14 words
The method of claim 19 further comprising mixing an organohydrogenpolysiloxane and a vinyl-containing polysiloxane.
Claim 38
Dependent Claim 26 words
The method of claim 19 or 32 further comprising mixing an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 39
Independent Claim 193 words
A method for making a curable composition comprising mixing: (A) a polysiloxane having the general formula: ##STR19## where R is substantially all methyl radicals or a mixture of methyl and phenyl radicals; R 1 is selected from the group consisting of hydrogen atoms, hydroxyl radicals, methyl radicals and methoxy radicals; R 2 is a vinyl radical; x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy radicals; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy radicals; and x+y+z is a number such that the viscosity of said polysiloxane varies from about 100 centipoise to about 10,000 centipoise at 25° C.; (B) from 0.1 to 10 parts by weight per 100 parts by weight of (A) of a photoinitiator selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and chlorobenzoate; (C) from 10 ppm to 500 ppm based on (A) of a platinum-containing hydrosilation catalyst, as platinum metal; (D) an organohydrogenpolysiloxane; (E) a vinyl-containing polydiorganosiloxane; and (F) an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 40
Independent Claim 193 words
A method for making a curable composition comprising mixing: (A) a polysiloxane having the general formula: ##STR19## where R is substantially all methyl radicals or a mixture of methyl and phenyl radicals; R 1 is selected from the group consisting of hydrogen atoms, hydroxyl radicals, methyl radicals and methoxy radicals; R 2 is a vinyl radical; x is a number such that there is present from about 1.0 to about 10.0 mole percent vinyl-containing siloxy radicals; y is a number such that there is present from about 2.0 to about 20.0 mole percent hydrogen-containing siloxy radicals; and x+y+z is a number such that the viscosity of said polysiloxane varies from about 100 centipoise to about 10,000 centipoise at 25° C.; (B) from 0.1 to 10 parts by weight per 100 parts by weight of (A) of a photoinitiator selected from the group consisting of t-butylperbenzoate, t-butylper-p-nitrobenzoate, t-butylper-p-methoxybenzoate, t-butylper-p-methylbenzoate, and chlorobenzoate; (C) from 10 ppm to 500 ppm based on (A) of a platinum-containing hydrosilation catalyst, as platinum metal; (D) an organohydrogenpolysiloxane; (E) a vinyl-containing polydiorganosiloxane; and (F) an inhibitor effective for preventing curing of said composition at temperatures below the heat cure temperature.
Claim 41
Dependent Claim 94 words
An article of manufacture comprising: (a) 100 parts by weight of component A and (b) 1 to 100 parts by weight of component B, wherein component A comprises a mixture of (i) one or more polysiloxanes having both silicon-bonded olefinic radicals and silicon-bonded hydrogen atoms and (ii) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and component B comprises a precious metal-containing photocatalyst dispersed in a vinyl-containing polysiloxane, and wherein component A and component B are contained separate from one another.
Claim 42
Dependent Claim 94 words
An article of manufacture comprising: (a) 100 parts by weight of component A and (b) 1 to 100 parts by weight of component B, wherein component A comprises a mixture of (i) one or more polysiloxanes having both silicon-bonded olefinic radicals and silicon-bonded hydrogen atoms and (ii) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and component B comprises a precious metal-containing photocatalyst dispersed in a vinyl-containing polysiloxane, and wherein component A and component B are contained separate from one another.
Claim 43
Dependent Claim 131 words
The article of claim 35 wherein component A (i) is a polysiloxane having the general formula: ##STR20## where each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane ranges from about 25 centipoise to about 2,500,000 centipoise at 25° C.
Claim 44
Dependent Claim 205 words
An article of manufacture prepared by the steps comprising: I. mixing, so as to form a curable composition comprising: (A) a polysiloxane having the general formula: ##STR21## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical, or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 to about 2,500,000 centipoise at 25° C.; (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst; II. applying a coating of said curable composition to a substrate; and III. curing said coating to said substrate by exposing the coated substrate to a source of ultraviolet radiation and thereafter thermally curing said coating.
Claim 45
Dependent Claim 205 words
An article of manufacture prepared by the steps comprising: I. mixing, so as to form a curable composition comprising: (A) a polysiloxane having the general formula: ##STR21## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical, or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 to about 2,500,000 centipoise at 25° C.; (B) at least one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst; II. applying a coating of said curable composition to a substrate; and III. curing said coating to said substrate by exposing the coated substrate to a source of ultraviolet radiation and thereafter thermally curing said coating.
Claim 46
Dependent Claim 10 words
The article of claim 37 wherein the substrate is paper.
Claim 47
Dependent Claim 12 words
The article of claim 37 wherein the substrate is a circuit board.
Claim 48
Dependent Claim 13 words
The article of claim 37 wherein thermal curing is effected at room temperature.
Claim 49
Dependent Claim 14 words
The article of claim 37 wherein thermal curing is effected at an elevated temperature.
Claim 50
Independent Claim 205 words
A method for making an article of manufacture comprising: I. mixing, so as to form a curable composition comprising: (A) a polysiloxane having the general formula: ##STR22## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical, or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 to about 2,500,000 centipoise at 25° C.; (B) at lease one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst; II. applying a coating of said curable composition to a substrate; and III. curing said coating to said substrate by exposing the coated substrate to a source of ultraviolet radiation and thereafter thermally curing said coating.
Claim 51
Independent Claim 205 words
A method for making an article of manufacture comprising: I. mixing, so as to form a curable composition comprising: (A) a polysiloxane having the general formula: ##STR22## wherein each R is an independently selected substituted or unsubstituted monovalent hydrocarbon radical having from 1 to 20 carbon atoms; R 1 is hydrogen, a hydroxyl radical, or a substituted or unsubstituted hydrocarbon or hydrocarbonoxy radical having from 1 to 20 carbon atoms; R 2 is a lower alkenyl radical; x is a number such that there is present from about 0.1 to about 20 mole percent vinyl-containing siloxy units; y is a number such that there is present from about 0.5 to about 50 mole percent hydrogen-containing siloxy units; and x+y+z is a number such that the viscosity of said polysiloxane is from about 25 to about 2,500,000 centipoise at 25° C.; (B) at lease one part by weight per 100 parts by weight of said polydiorganosiloxane of at least one free radical photoinitiator; and (C) a precious metal-containing hydrosilation catalyst; II. applying a coating of said curable composition to a substrate; and III. curing said coating to said substrate by exposing the coated substrate to a source of ultraviolet radiation and thereafter thermally curing said coating.
Claim 52
Dependent Claim 10 words
The method of claim 42 wherein the substrate is paper.
Claim 53
Dependent Claim 12 words
The method of claim 42 wherein the substrate is a circuit board.
Claim 54
Dependent Claim 13 words
The method of claim 42 wherein thermal curing is effected at room temperature.
Claim 55
Dependent Claim 14 words
The method of claim 42 wherein thermal curing is effected at an elevated temperature.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

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