US4009224A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Epoxy resin powder including ethylene vinyl acetate
Assignee: 3M Co
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Filing: 1975-08-11
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Granted: 1977-02-22
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Expires: 1995-08-11
Abstract
Abstract Stable, free-flowing epoxy resin powder which fuses to and cures upon striking an object which has been preheated to the curing temperature of the composition to provide a tough protective coating. The composition of the powder differs from the prior art in that it includes 3-30 parts of a copolymer of 2-50% vinyl acetate and 5-75% ethylene per 100 parts of the epoxy resin. The copolymer improves the flexibility of the cured coatings.
Inventors
- 👤 Gerald H. Warnken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:43
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/4007; C08G59/4014; C08G59/4035; C08K; C08K5/00; C08K5/16; C08K5/22; C08K5/24; C08K5/25; C08L; C08L23/00; C08L23/02; C08L23/04; C08L31/00; C08L31/02; C08L31/04; C08L63/00; C09; C09D; C09D163/00; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31511; Y10T428/31529
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
143 words
A homogeneous free-flowing powder which is shelf-stable and when heated to 185°-250° C in contact with a metal article fuses and then gels to provide a tough protective coating, said powder comprising a polyglycidyl ether of a polyhydric phenol having a softening point of 70°-150° C, a normally solid latent hardening agent for epoxy resin, a latent catalyst for accelerating reaction between the polyglycidyl ether and the hardening agent when melted together, which powder is characterized by the feature that it incorporates per 100 parts of the polyglycidyl ether 3-30 parts by weight of one or more copolymers of monomers comprising by weight 2-50% vinyl acetate and 5-75% ethylene, which copolymer or copolymers have a melt index or combined melt index of 5-400 and impart extraordinarily good flexibility to cured coatings of the powder without undue effect upon other properties of the coatings.
Claim 2
Dependent Claim
143 words
A homogeneous free-flowing powder which is shelf-stable and when heated to 185°-250° C in contact with a metal article fuses and then gels to provide a tough protective coating, said powder comprising a polyglycidyl ether of a polyhydric phenol having a softening point of 70°-150° C, a normally solid latent hardening agent for epoxy resin, a latent catalyst for accelerating reaction between the polyglycidyl ether and the hardening agent when melted together, which powder is characterized by the feature that it incorporates per 100 parts of the polyglycidyl ether 3-30 parts by weight of one or more copolymers of monomers comprising by weight 2-50% vinyl acetate and 5-75% ethylene, which copolymer or copolymers have a melt index or combined melt index of 5-400 and impart extraordinarily good flexibility to cured coatings of the powder without undue effect upon other properties of the coatings.
Claim 3
Dependent Claim
27 words
A powder as defined in claim 1 wherein a said copolymer is a copolymer of 25-50 weight percent of vinyl acetate and 50-75 weight percent of ethylene.
Claim 4
Dependent Claim
25 words
A powder as defined in claim 1 wherein a said copolymer is also based on about 1 weight percent of acrylic acid or maleic acid.
Claim 5
Dependent Claim
27 words
A powder as defined in claim 1 wherein the composition includes 3-10 parts by weight of said copolymer or copolymers per 100 parts of the polyglycidyl ether.
Claim 6
Dependent Claim
23 words
A powder as defined in claim 1 wherein said one or more copolymers have a melt index or combined melt index of 20-200.
Claim 7
Dependent Claim
19 words
A dry shelf-stable powder as defined in claim 1, most of which will pass a screen having 180-micrometer openings.
References Cited (Backward Citations)
US3578615A
Cited
US3626026A
Cited
US3684778A
Cited
US3661828A
Cited
US3707583A
Cited
US3758633A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-22 | 1980-08-23 | 1981-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-22 | 1984-08-23 | 1985-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-22 | 1988-08-23 | 1989-02-22 | $7700.00 | Window Closed / Lapsed |