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US4287114A Expired / Lapsed US ⏱️ 0.0 years remaining

Primer compositions

Assignee: Shin-Etsu Chemical Co Ltd
•
Filing: 1979-11-06
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Granted: 1981-09-01
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Expires: 1999-11-06
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Abstract

Abstract The adhesive bonding of a silicone rubber to a metal surface can be very much improved by the use of the inventive primer composition, in particular, with respect to the heat resistance and anti-oil resistance of the adhesion. The inventive primer composition comprises (a) a substantially linear diorganopolysiloxane of gum-like consistency free from aliphatic unsaturation, (b) an organopolysiloxane with the organic group/silicon atom molar ratio of 1.9 to 2.3 and having a limited amount of vinyl groups directly bonded to the silicon atoms and a viscosity of 5 to 10,000 centistokes at 25 DEG C., (c) an organopolysiloxane resin with the molar ratio of organic groups/silicon atoms of 0.5 to 1.7, (d) an organosilane compound such as vinyl trimethoxysilane or vinyl tris(2-methoxyethoxy) silane, (e) a finely divided silica filler, (f) an organic peroxide and (g) a curing agent for silicone resins, all in limited weight proportions.

Inventors

  • 👤 Kunio Itoh
  • 👤 Takeshi Fukuda
  • 👤 Masaaki Matumura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 10:54
CPC Classifications
C; C09; C09D; C09D183/00; C09D183/04; C08; C08K; C08K3/00; C08K3/34; C08K3/36; C08K5/00; C08K5/04; C08K5/14; C08K5/54; C08L; C08L83/00; C08L83/04

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 286 words
A primer composition which comprises (a) 100 parts by weight of an organopolysiloxane of substantially linear molecular structure represented by the average unit formula ##EQU4## where R 1 is a substituted or unsubstituted monovalent hydrocarbon group substantially free from aliphatic unsaturation and a is a positive number in the range from 0.98 to 2.01, and having a viscosity larger than 100,000 centistokes at 25° C., (b) from 5 to 100 parts by weight of a vinyl-containing organopolysiloxane represented by the average unit formula ##EQU5## where R 2 is a substituted or unsubstituted monovalent hydrocarbon group and b is a positive number in the range from 1.9 to 2.3, from 0.03 to 1 of the groups represented by R 2 per silicon atom in a molecule being vinyl groups, and having a viscosity from 5 to 10,000 centistokes at 25° C., (c) from 5 to 100 parts by weight of an organopolysiloxane resin represented by the average unit formula ##EQU6## where R 3 is a substituted or unsubstituted monovalent hydrocarbon group and c is a positive number in the range from 0.5 to 1.7, (d) from 0.5 to 200 parts by weight of an organosilane compound represented by the general formula R.sup.4 Si(OR.sup.5).sub.3, where R 4 is an aliphatically unsaturated monovalent hydrocarbon group and R 5 is a monovalent group selected from the class consisting of alkyl groups having 1 to 5 carbon atoms, 2-methoxyethyl and 2-ethoxyethyl groups, (e) from 5 to 100 parts by weight of a silica filler having a specific surface area of at least 100 m 2 /g, (f) from 0 to 10 parts by weight of an organic peroxide, and (g) from 0.5 to 50 parts by weight of a condensation catalyst.
Claim 2
Dependent Claim 286 words
A primer composition which comprises (a) 100 parts by weight of an organopolysiloxane of substantially linear molecular structure represented by the average unit formula ##EQU4## where R 1 is a substituted or unsubstituted monovalent hydrocarbon group substantially free from aliphatic unsaturation and a is a positive number in the range from 0.98 to 2.01, and having a viscosity larger than 100,000 centistokes at 25° C., (b) from 5 to 100 parts by weight of a vinyl-containing organopolysiloxane represented by the average unit formula ##EQU5## where R 2 is a substituted or unsubstituted monovalent hydrocarbon group and b is a positive number in the range from 1.9 to 2.3, from 0.03 to 1 of the groups represented by R 2 per silicon atom in a molecule being vinyl groups, and having a viscosity from 5 to 10,000 centistokes at 25° C., (c) from 5 to 100 parts by weight of an organopolysiloxane resin represented by the average unit formula ##EQU6## where R 3 is a substituted or unsubstituted monovalent hydrocarbon group and c is a positive number in the range from 0.5 to 1.7, (d) from 0.5 to 200 parts by weight of an organosilane compound represented by the general formula R.sup.4 Si(OR.sup.5).sub.3, where R 4 is an aliphatically unsaturated monovalent hydrocarbon group and R 5 is a monovalent group selected from the class consisting of alkyl groups having 1 to 5 carbon atoms, 2-methoxyethyl and 2-ethoxyethyl groups, (e) from 5 to 100 parts by weight of a silica filler having a specific surface area of at least 100 m 2 /g, (f) from 0 to 10 parts by weight of an organic peroxide, and (g) from 0.5 to 50 parts by weight of a condensation catalyst.
Claim 3
Dependent Claim 23 words
The primer composition as claimed in claim 1 wherein the group represented by R 1 is a methyl group or a phenyl group.
Claim 4
Dependent Claim 29 words
The primer composition as claimed in claim 1 wherein the group represented by R 2 is a group selected from the class consisting of methyl, phenyl and vinyl groups.
Claim 5
Dependent Claim 29 words
The primer composition as claimed in claim 1 wherein the groups represented by R 3 is a group selected from the class consisting of methyl, phenyl and vinyl groups.
Claim 6
Dependent Claim 20 words
The primer composition as claimed in claim 1 wherein the number c is in the range from 1.2 to 1.5.
Claim 7
Dependent Claim 22 words
The primer composition as claimed in claim 1 wherein the group represented by R 4 is a vinyl or an ethynyl group.
Claim 8
Dependent Claim 23 words
The primer composition as claimed in claim 1 wherein the organosilane compound as the component (d) is vinyl trimethoxysilane or vinyl tris(2-methoxyethoxy) silane.
Claim 9
Dependent Claim 25 words
The primer composition as claimed in claim 1 wherein the organic peroxide is selected from the class consisting of dicumyl peroxide, tert-butylperbenzoate and 2,5-dimethyl-2,5-di(tertbutylperoxy) hexane.
Claim 10
Dependent Claim 35 words
The primer composition as claimed in claim 1 wherein component (g) is selected from the class consisting of carboxylates of divalent tin, carboxylates of tetravalent tin, organic esters of tetravalent titanic acid and amine compounds.
Claim 11
Dependent Claim 20 words
The primer composition as claimed in claim 1 further comprising from 5 to 20 parts by weight of iron oxide.
Claim 12
Dependent Claim 40 words
The primer composition as claimed in claim 1 wherein the organopolysiloxane as the component (a) contains vinyl groups as part of the groups represented by R 1 in an amount not exceeding 0.005 moles per mole of the silicon atoms.

References Cited (Backward Citations)

US2803619A Cited
US3699073A Cited
US3779986A Cited
US3769253A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-08-31 1985-03-02 1985-09-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-08-31 1989-03-02 1989-09-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-08-31 1993-03-02 1993-09-01 $7700.00 Window Closed / Lapsed

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