Patent US3988291A successfully refreshed from Google Patents.
US3988291A
Expired / Lapsed
US
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Precision-moldable abrasion-resistant molding composition and moldings
Assignee: ROSTONE ACQUISITION Corp
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Filing: 1975-05-27
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Granted: 1976-10-26
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Expires: 1995-05-27
Abstract
Abstract Mineral-filled thermosetting molding compositions having both precision-molding or low-shrink characteristics and also high abrasion resistance, plus other desirable properties. "Low profile" molding compositions, known to give smooth surface configurations, have low-shrink properties which also give precision molding characteristics of value in mechanically interfitting molded parts, but have such poor abrasion resistance as to be unusable for desirable applications. Both low-shrink and high abrasion resistance are obtained, with other desired properties, by including a known abrasion-improving polyolefin and by using a long-fiber asbestos as the reinforcing fiber, particularly either chrysotile asbestos or that known as blue asbestos or crocidolite.
Inventors
- 👤 Maurice G. Knoy
- 👤 Robert E. Wilkinson
- 👤 Kenneth W. Johansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 18:06
CPC Classifications
C; C08; C08K; C08K7/00; C08K7/02; C08K7/04; C08K7/10; C08K7/12; C08K3/00; C08K3/18; C08K3/20; C08K3/34; C08L; C08L23/00; C08L31/00; C08L31/02; C08L31/04; C08L67/00; C08L67/04; C08L67/06
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
115 words
A molding composition adapted to undergo thermosetting reaction under molding conditions to produce a molding having both low-shrink characteristics and high abrasion resistance, comprising from 15% to 60% by weight of a low-profile resin system containing a free-radical initiated thermosetting polymer, a free-radical initiator therefor, a copolymerizable monomer, and a thermoplastic resin low-shrink additive, from about 5% to about 40% of long fiber asbestos, such asbestos constituting substantially the entire fiber content of the composition, from about 20% to about 80% of other mineral filler, not including any substantial amount of glass fiber, and from about one-half percent to about 10% of an abrasion-improving additive consisting of a polyolefin which is solid at room temperature.
Claim 2
Dependent Claim
115 words
A molding composition adapted to undergo thermosetting reaction under molding conditions to produce a molding having both low-shrink characteristics and high abrasion resistance, comprising from 15% to 60% by weight of a low-profile resin system containing a free-radical initiated thermosetting polymer, a free-radical initiator therefor, a copolymerizable monomer, and a thermoplastic resin low-shrink additive, from about 5% to about 40% of long fiber asbestos, such asbestos constituting substantially the entire fiber content of the composition, from about 20% to about 80% of other mineral filler, not including any substantial amount of glass fiber, and from about one-half percent to about 10% of an abrasion-improving additive consisting of a polyolefin which is solid at room temperature.
Claim 3
Dependent Claim
17 words
A molding composition as in claim 1 in which the asbestos is either chrysotile or crocidolite asbestos.
Claim 4
Dependent Claim
16 words
A molding composition as in claim 2 in which the thermosetting polymer is a polyester polymer.
Claim 5
Dependent Claim
16 words
A molding composition as in claim 3 in which the other mineral filler is hydrated alumina.
Claim 6
Dependent Claim
24 words
A molding composition as in claim 2 in which the asbestos is present in an amount not exceeding that of the other mineral filler.
Claim 7
Dependent Claim
28 words
A molding composition as in claim 3 which contains about 30% resin system, about 15% asbestos, about 50% of hydrated alumina, and from 2% to 5% of polyethylene.
Claim 8
Dependent Claim
16 words
A molding composition as in claim 3 in which the abrasion-improving additive is a polyethylene resin.
Claim 9
Dependent Claim
16 words
A molding composition as in claim 3 in which the abrasion-improving additive is a polypropylene resin.
Claim 10
Dependent Claim
59 words
A molding composition as in claim 2 in which said low-shrink additive constitutes from about one-half percent to about 25% of the composition and is a polymerized thermoplastic compound which is soluble in said monomer or a compatible solvent intermixed therewith and which is not converted to a thermoset material under the conditions of molding and curing the composition.
Claim 11
Dependent Claim
28 words
A molding composition as in claim 2 in which said low-shrink additive is a polymer of vinyl acetate and constitutes from 5% to 40% of the resin system.
Claim 12
Dependent Claim
32 words
A molding composition as in claim 2 in which said low-shrink additive is a polymer having a polymerizable CH 2 =C= group and constitutes from 5% to 40% of the resin system.
Claim 13
Dependent Claim
29 words
A molding composition as in claim 2 in which said low-shrink additive is a polymer of a cyclic ester and constitutes from 5% to 40% of the resin system.
Claim 14
Dependent Claim
22 words
A cured thermoset molding having both low-shrink characteristics and high abrasion resistance, composed of a composition as set forth in claim 1.
Claim 15
Dependent Claim
22 words
A cured thermoset molding having both low-shrink characteristics and high abrasion resistance, composed of a composition as set forth in claim 2.
Claim 16
Dependent Claim
18 words
A molding as in claim 14 in which the thermosetting polymer of the composition is a polyester polymer.
Claim 17
Dependent Claim
15 words
A molding as in claim 15 in which the other mineral filler is hydrated alumina.
Claim 18
Dependent Claim
15 words
A molding as in claim 16 in which the abrasion-improving additive is polyethylene or polypropylene.
Claim 19
Dependent Claim
28 words
A molding as in claim 17 in which the low-shrink additive is a polymer of a cyclic ester and constitutes from 5% to 40% of the resin system.
Claim 20
Dependent Claim
28 words
A molding as in claim 17 in which the low-shrink additive is a polymer of a vinyl acetate and constitutes from 5% to 40% of the resin system.
Claim 21
Dependent Claim
31 words
A molding as in claim 17 in which the lowshrink additive is a polymer having a polymerizable CH 2 =CH= group and constitutes from 5% to 40% of the resin system.
Claim 22
Dependent Claim
69 words
A cured thermoset molding having both low-shrink characteristics and high abrasion resistance, composed of a cured composition containing: about 30% of a low-profile resin system containing a free-radical initiated polyester polymer, a free-radical initiator therefor, a copolymerizable monomer, and a thermoplastic resin low-shrink additive, about 15% of crysotile or crocidolite asbestos and no substantial amount of glass fiber, about 50% of hydrated alumina, and from 2% to 5% polyethylene.
Claim 23
Dependent Claim
69 words
A cured thermoset molding having both low-shrink characteristics and high abrasion resistance, composed of a cured composition containing: about 30% of a low-profile resin system containing a free-radical initiated polyester polymer, a free-radical initiator therefor, a copolymerizable monomer, and a thermoplastic resin low-shrink additive, about 15% of crysotile or crocidolite asbestos and no substantial amount of glass fiber, about 50% of hydrated alumina, and from 2% to 5% polyethylene.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-26 | 1980-04-26 | 1980-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-26 | 1984-04-26 | 1984-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-26 | 1988-04-26 | 1988-10-26 | $7700.00 | Window Closed / Lapsed |