US4142870A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Abrasive articles prepared from crosslinked aromatic polyimides
Assignee: Unicorn Industries Ltd
•
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 00:17
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.
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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) | 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 |