Patent DE609245C successfully refreshed from Google Patents.
Patent US3839264A successfully refreshed from Google Patents.
US3839264A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Varnishes of polyesterimides based on pentaerythritol
Assignee: Beck & Co AG
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Filing: 1972-03-15
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Granted: 1974-10-01
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Expires: 1992-03-15
Abstract
Abstract Electrical insulating varnish which is a solution of polyesterimide resin composed of a polyhydric alcohol component, a polycarboxylic acid component and five membered imide rings in the chain. At least part of the alcohol component is derived from pentaerythritol.
Inventors
- 👤 K Schmidt
- 👤 F Hansch
- 👤 H Rombrecht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:46
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/16; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/303; H01B3/306; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/294
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
87 words
AN ELECTRICALLY INSULATING VARNISH COMPRISING A SOLUTION IN A PHENOLIC SOLVENT OF A POLYESTERIMIDE RESIN COMPOSED OF POLYMER CONTAINING BOTH ESTER GROUPS COMPOSED OF A POLYHYDRIC ALCOHOL COMPONENT AND A POLYCARBOXYLIC ACID COMPONENT, AND FIVE CYCLIC IMIDE GROUPS IN THE POLYMERIC CHAIN COMPOSED OF AN AROMATIC CARBOXYLIC ACID ANHYDRIDE COMPONENT AND A PRIMARY AMINE COMPONENT, SAID POLYHYDRIC ALCOHOL COMPONENT COMPRISING AT LEAST ONE DIHYDRIC ALCOHOL, AND PENTAERYTHRITOL IN AN AMOUNT OF 2 TO 10 PERCENT REFERRED TO THE TOTAL WEIGHT OF RAW MATERIALS FOR THE POLYESTERIMIDE RESIN.
Claim 2
Dependent Claim
87 words
AN ELECTRICALLY INSULATING VARNISH COMPRISING A SOLUTION IN A PHENOLIC SOLVENT OF A POLYESTERIMIDE RESIN COMPOSED OF POLYMER CONTAINING BOTH ESTER GROUPS COMPOSED OF A POLYHYDRIC ALCOHOL COMPONENT AND A POLYCARBOXYLIC ACID COMPONENT, AND FIVE CYCLIC IMIDE GROUPS IN THE POLYMERIC CHAIN COMPOSED OF AN AROMATIC CARBOXYLIC ACID ANHYDRIDE COMPONENT AND A PRIMARY AMINE COMPONENT, SAID POLYHYDRIC ALCOHOL COMPONENT COMPRISING AT LEAST ONE DIHYDRIC ALCOHOL, AND PENTAERYTHRITOL IN AN AMOUNT OF 2 TO 10 PERCENT REFERRED TO THE TOTAL WEIGHT OF RAW MATERIALS FOR THE POLYESTERIMIDE RESIN.
Claim 3
Dependent Claim
23 words
A varnish according to claim 1, wherein the polybasic acid component used to form said polyesterimide resin comprises bis-4, 4'' - (trimellitic acid-imido)-diphenylmethane.
Claim 4
Dependent Claim
27 words
A varnish according to claim 2, wherein said polybasic acid component includes an acid selected from the group consisting of terephthalic acid, isophthalic acid, and trimellitic acid.
Claim 5
Dependent Claim
34 words
A varnish according to claim 1 wherein said polyhydric alcohol component includes at least one dihydric alcohol selected from the group consisting of bis-N, N'' - (2-hydroxethyl)-pyromellitic acid diimide and bis-N, N''-(3-hydroxypropyl)-pyromellitic acid di-imide.
Claim 6
Dependent Claim
28 words
A varnish according to claim 4, wherein said polyhydric alcohol component includes at least one dihydric alcohol selected from the group consisting of ethylene glycol and propylene glycol.
Claim 7
Dependent Claim
16 words
A varnish according to claim 1, said solution being of said polyesterimide in a cresol solvent.
Claim 8
Dependent Claim
30 words
A varnish according to claim 1, said pentaerythritol being used in an amount of 3-7 percent by weight, referred to the total weight of raw materials for the polyesterimide resin.
References Cited (Backward Citations)
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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) | 1977-09-30 | 1978-04-01 | 1978-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-30 | 1982-04-01 | 1982-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-30 | 1986-04-01 | 1986-10-01 | $7700.00 | Window Closed / Lapsed |