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US3839264A Expired / Lapsed US ⏱️ 0.0 years remaining

Varnishes of polyesterimides based on pentaerythritol

Assignee: Beck & Co AG
•
Filing: 1972-03-15
•
Granted: 1974-10-01
•
Expires: 1992-03-15
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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 01:47
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)

US2777830A Cited
US2936296A Cited
US3238181A Cited
US3234181A Cited
US3697471A Cited
US3274159A Cited

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

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