Patent US3614743A successfully refreshed from Google Patents.
Patent US4142870A successfully refreshed from Google Patents.
US4142870A
Expired / Lapsed
US
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Abrasive articles prepared from crosslinked aromatic polyimides
Assignee: Unicorn Industries Ltd
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Filing: 1977-08-15
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Granted: 1979-03-06
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Expires: 1997-08-15
Abstract
Abstract An abrasive article comprising a filler distributed in a matrix or binder of polyimide polymeric material of a crosslinked combination of two linear aromatic polyimide polymers. These articles exhibit a retention of physical properties at high temperatures.
Inventors
- 👤 Elwyn R. Lovejoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:59
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1042; C08G73/1003; C08G73/1007; C08G73/1028
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
133 words
In an abrasive article of a matrix and filler particles including abrasive particles substantially homogeneously distributed throughout the matrix, the improvement wherein the matrix is a crosslinked aromatic polyimide polymeric material comprising a crosslinked chemical combination of (a) a higher molecular weight base resin of linear aromatic polyimide polymer having at least one ketonic carbonyl per repeat unit and a molecular weight of from 3,000 to 300,000 and (b) a lower molecular weight crosslinker resin of linear aromatic polyimide polymer having amine end-groups and a molecular weight of from 500 to 15,000; wherein the mole ratio of crosslinker resin to base resin is in the range of greater than 2 to 40 and wherein the molecular weight ratio of higher molecular weight resin to lower molecular weight resin is from 2 to 50.
Claim 2
Dependent Claim
133 words
In an abrasive article of a matrix and filler particles including abrasive particles substantially homogeneously distributed throughout the matrix, the improvement wherein the matrix is a crosslinked aromatic polyimide polymeric material comprising a crosslinked chemical combination of (a) a higher molecular weight base resin of linear aromatic polyimide polymer having at least one ketonic carbonyl per repeat unit and a molecular weight of from 3,000 to 300,000 and (b) a lower molecular weight crosslinker resin of linear aromatic polyimide polymer having amine end-groups and a molecular weight of from 500 to 15,000; wherein the mole ratio of crosslinker resin to base resin is in the range of greater than 2 to 40 and wherein the molecular weight ratio of higher molecular weight resin to lower molecular weight resin is from 2 to 50.
Claim 3
Dependent Claim
12 words
An abrasive article of claim 1 wherein said abrasive particles comprise diamonds.
Claim 4
Dependent Claim
11 words
An abrasive article of claim 1 shaped as an abrasive wheel.
References Cited (Backward Citations)
US3179631A
Cited
US3904391A
Cited
US3416994A
Cited
US3523773A
Cited
US3632554A
Cited
US3554935A
Cited
US3585013A
Cited
US3533997A
Cited
US3621076A
Cited
US3781237A
Cited
US3883452A
Cited
US3897395A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |