US4009141A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical insulating compositions of epoxy resins, zirconium silicate and alumina
Assignee: General Electric Co
•
Filing: 1972-07-07
•
Granted: 1977-02-22
•
Expires: 1992-07-07
Abstract
Abstract Composition for use in making electrical insulating products such as transformer bushings comprises a mixture of cycloaliphatic epoxy resin, an anhydride curing agent, and a filler material including zirconium silicate and hydrated alumina. To provide for increased pot life of the material, the epoxy resin and a portion of the filler material are stored in one heated vessel while the anhydride curing agent and the remaining filler material are held in a separate heated vessel, the two components being mixed together prior to pouring the material into the product mold.
Inventors
- 👤 Frank S. Nichols
- 👤 Charles H. Bliss
- 👤 Robert J. Londergan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 09:36
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; C08K3/34; C08K5/00; C08K5/04; C08K5/09; Y; Y10; Y10S; Y10S524/00; Y10S524/906
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
73 words
The method of making a hardenable epoxy resin composition which comprises providing a first mixture comprising a cycloaliphatic epoxy resin compound and a finely divided filler material comprising zirconium silicate and hydrated alumina, providing a second mixture comprising an anhydride curing agent for said epoxy resin compound and a finely divided filler material comprising zirconium silicate, and thereafter mixing together said first mixture and said second mixture for curing said epoxy resin compound.
Claim 2
Independent Claim
73 words
The method of making a hardenable epoxy resin composition which comprises providing a first mixture comprising a cycloaliphatic epoxy resin compound and a finely divided filler material comprising zirconium silicate and hydrated alumina, providing a second mixture comprising an anhydride curing agent for said epoxy resin compound and a finely divided filler material comprising zirconium silicate, and thereafter mixing together said first mixture and said second mixture for curing said epoxy resin compound.
Claim 3
Dependent Claim
18 words
A method as defined in claim 1, said first and second mixtures being heated at about 70°-100° C.
Claim 4
Dependent Claim
51 words
A method as defined in claim 2, said first mixture having the following composition in percent by weight: ______________________________________
Cycloaliphatic epoxy resin
20-37%
Zirconium silicate 54-66
Hydrated alumina 9-36
______________________________________
and said second mixture having the following composition in percent by
weight: ______________________________________
Dicarboxylic acid anhydride
15-30%
Zirconium silicate 70-85
______________________________________
Claim 5
Dependent Claim
35 words
A method as defined in claim 3, wherein said first and second mixtures are mixed together in proportions to provide about 0.05-1.0 mole of said anhydride curing agent per epoxy equivalent of said epoxy resin.
Claim 6
Dependent Claim
29 words
A method as defined in claim 4, wherein said second mixture includes about 0.2-1% by weight of a curing catalyst for accelerating the curing of said epoxy resin compound.
Claim 7
Dependent Claim
56 words
A method as defined in claim 5, said first mixture having the following approximate composition in percent by weight: ______________________________________
Cycloaliphatic epoxy resin
24%
Zirconium silicate 58
Hydrated alumina 18
______________________________________
and said second mixture having the following approximate composition in
percent by weight: ______________________________________
Dicarboxylic acid anhydride
15%
Zirconium silicate 84.5
Curing catalyst 0.5
______________________________________
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) | 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 |