Patent US3856908A successfully refreshed from Google Patents.
US3856908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for molding from a flexible mold
Assignee: Dow Silicones Corp
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Filing: 1970-10-12
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Granted: 1974-12-24
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Expires: 1990-10-12
Abstract
Abstract A method of forming shaped articles of polyester, polyurethane or epoxy resin by using a flexible mold wherein a thin continuous film of a methyl ethyl ketone soluble copolymer of vinylidene chloride and acrylonitrile is applied to the shape forming surface of the flexible mold prior to molding an article is disclosed. This process provides a shaped article having a thin coating of the copolymer of vinylidene chloride and acrylonitrile on the surface. This process extends the useful life of the mold.
Inventors
- 👤 J Harper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:03
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/56; B29C33/60; B29C33/62; B29C33/38; B29C33/40; B29C33/405; B29C37/00; B29C37/0025; B29C37/0028; B29C2037/0035; B29K; B29K2875/00; B29K2883/00
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
87 words
IN A METHOD OF FORMING A SHAPED ARTICLE CONSISTING ESSENTIALLY OF PLACING A CURABLE, CATALYZED, POLYMERIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF POLYESTER, POLYURETHANE AND EPOXY RESIN IN A FLEXIBLE MOLD, CURING SAID POLYMERIC MATERIAL AND THEREAFTER REMOVING THE SHAPED ARTICLE FROM THE MOLD, THE IMPROVEMENT CONSISTING ESSENTIALLY OF APPLYING A THIN CONTINUOUS FILM OF A METHYL ETHYL KETONE SOLUBLE COPOLYMER OF VINYLIDENE CHLORIDE AND ACRYLONITRILE ON THE SHAPE FORMING SURFACE OF SAID FLEXIBLE MOLD BEFORE PLACING THE CURABLE, CATALYZED, POLYMERIC MATERIAL IN THE FLEXIBLE MOLD.
Claim 2
Dependent Claim
87 words
IN A METHOD OF FORMING A SHAPED ARTICLE CONSISTING ESSENTIALLY OF PLACING A CURABLE, CATALYZED, POLYMERIC MATERIAL SELECTED FROM THE GROUP CONSISTING OF POLYESTER, POLYURETHANE AND EPOXY RESIN IN A FLEXIBLE MOLD, CURING SAID POLYMERIC MATERIAL AND THEREAFTER REMOVING THE SHAPED ARTICLE FROM THE MOLD, THE IMPROVEMENT CONSISTING ESSENTIALLY OF APPLYING A THIN CONTINUOUS FILM OF A METHYL ETHYL KETONE SOLUBLE COPOLYMER OF VINYLIDENE CHLORIDE AND ACRYLONITRILE ON THE SHAPE FORMING SURFACE OF SAID FLEXIBLE MOLD BEFORE PLACING THE CURABLE, CATALYZED, POLYMERIC MATERIAL IN THE FLEXIBLE MOLD.
Claim 3
Dependent Claim
48 words
The method in accordance with claim 1, in which an organic solvent solution of the copolymer of vinylidene chloride and acrylonitrile is applied to the shape-forming surface of the flexible mold and thereafter evaporating the organic solvent before placing the curable, catalyzed, polymeric material in the flexible mold.
Claim 4
Dependent Claim
32 words
The method in accordance with claim 2, in which the organic solvent solution of the copolymer of vinylidene chloride and acrylonitrile is sprayed on the shape forming surface of the flexible mold.
Claim 5
Dependent Claim
25 words
The method in accordance with claim 2, in which the organic solvent solution of the copolymer of vinylidene chloride and acrylonitrile also contains a pigment.
Claim 6
Dependent Claim
25 words
The method in accordance with claim 3 in which the organic solvent solution of the copolymer of vinylidene chloride and acrylonitrile also contains a pigment.
Claim 7
Dependent Claim
16 words
The method in accordance with claim 1, in which the flexible mold is a silicone rubber.
Claim 8
Dependent Claim
16 words
The method in accordance with claim 1, in which the flexible mold is a urethane elastomer.
Claim 9
Dependent Claim
15 words
The method in accordance with claim 5 in which the flexible mold is silicone rubber.
Claim 10
Dependent Claim
15 words
The method in accordance with claim 5 in which the flexible mold is urethane elastomer.
Claim 11
Independent Claim
71 words
A method of forming a shaped article consisting essentially of A. coating a shape forming surface of a flexible mold with a thin continuous film of a methyl ethyl ketone soluble copolymer of vinylidene chloride and acrylonitrile, B. placing a curable, catalyzed, polymeric material selected from the group consisting of polyester, polyurethane and epoxy resin in the flexible mold, C. curing the polymeric material, and thereafter D. removing the shaped article.
Claim 12
Independent Claim
71 words
A method of forming a shaped article consisting essentially of A. coating a shape forming surface of a flexible mold with a thin continuous film of a methyl ethyl ketone soluble copolymer of vinylidene chloride and acrylonitrile, B. placing a curable, catalyzed, polymeric material selected from the group consisting of polyester, polyurethane and epoxy resin in the flexible mold, C. curing the polymeric material, and thereafter D. removing the shaped article.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-23 | 1978-06-24 | 1978-12-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-23 | 1982-06-24 | 1982-12-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-23 | 1986-06-24 | 1986-12-24 | $7700.00 | Window Closed / Lapsed |