US3873497A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilization of polyamides
Assignee: Imperial Chemical Industries Ltd
•
Filing: 1971-04-02
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Granted: 1975-03-25
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Expires: 1991-04-02
Abstract
Abstract Fibre-forming synthetic polyamides or copolyamides having improved stability imparted by defined class of phosphoruscontaining phenols in combination with low amount of reducing phosphorus compounds.
Inventors
- 👤 John Ernest Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:32
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/49; C08K5/51; C08K5/52
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
101 words
AN IMPROVED FIBER-FORMING SYNTHETIC POLYAMIDE WHEREIN THE IMPROVEMENT CONSISTS IN THAT IN SAID POLYAMIDE THERE HAVE BEEN INCORPORATED FROM 5 TO 100 PARTS PER MILLION PARTS BY WEIGHT ON THE POLYAMIDE OF REDUCING PHOSPHORUS IN THE FORM OF A PHOSPHOROUS ACID OR A SALT OR ESTER THEREOF AND 100 TO 10,000 PARTS PER MILLION BY WEIGHT ON THE POLYAMIDE OF A PHOSPHORUS-CONTAINING PHENOL OF THE GENERAL FORMULA: (HO$ O)3PO WHERE $ REPRESENTS A BENZENE RING, WITH THE OH HYDROXYL GROUPS POSITIONED PARA- OR ORTHO- TO THE PHOSPHORUS ATOM AND WITH ON OR TOW ALKYL GROUPS ADJACENT TO THE PHENOLIC HYDROXYL GROUPS.
Claim 2
Dependent Claim
101 words
AN IMPROVED FIBER-FORMING SYNTHETIC POLYAMIDE WHEREIN THE IMPROVEMENT CONSISTS IN THAT IN SAID POLYAMIDE THERE HAVE BEEN INCORPORATED FROM 5 TO 100 PARTS PER MILLION PARTS BY WEIGHT ON THE POLYAMIDE OF REDUCING PHOSPHORUS IN THE FORM OF A PHOSPHOROUS ACID OR A SALT OR ESTER THEREOF AND 100 TO 10,000 PARTS PER MILLION BY WEIGHT ON THE POLYAMIDE OF A PHOSPHORUS-CONTAINING PHENOL OF THE GENERAL FORMULA: (HO$ O)3PO WHERE $ REPRESENTS A BENZENE RING, WITH THE OH HYDROXYL GROUPS POSITIONED PARA- OR ORTHO- TO THE PHOSPHORUS ATOM AND WITH ON OR TOW ALKYL GROUPS ADJACENT TO THE PHENOLIC HYDROXYL GROUPS.
Claim 3
Dependent Claim
22 words
A polyamide according to claim 1 wherein there have been incorporated from 400 to 1,000 parts per million of said phosphorus-containing phenol.
Claim 4
Dependent Claim
21 words
A polyamide as claimed in claim 1 wherein there have been incorporated from 5 to 1,000 parts per million of manganese.
Claim 5
Dependent Claim
21 words
A polyamide as claimed in claim 1 wherein there have been incorporated from 10 to 100 parts per million of manganese.
Claim 6
Dependent Claim
27 words
A polyamide as claimed in claim 1 wherein hydroxyl groups of the phosphorus-containing phenol are located symmetrically on benzene rings in the para-positions to the P atom.
Claim 7
Dependent Claim
18 words
A polyamide as claimed in claim 1 wherein said polyamide is polyhexamethylene adipamide, with or without added pigment.
Claim 8
Dependent Claim
17 words
Fibres, filaments, yarns, fabrics and other textile materials shaped from the polyamides as claimed in claim 1.
Claim 9
Dependent Claim
39 words
A polyamide as claimed in claim 1 wherein there have been incorporated from 50 to 100 parts per million parts by weight of polyamide of said phosphorus in the form of a phosphorous acid or salt or ester thereof.
References Cited (Backward Citations)
US2437232A
Cited
US2493597A
Cited
US2510777A
Cited
US2640044A
Cited
US2887462A
Cited
US3441575A
Cited
US3324071A
Cited
US3300440A
Cited
US3412064A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-24 | 1978-09-23 | 1979-03-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-24 | 1982-09-23 | 1983-03-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-24 | 1986-09-23 | 1987-03-25 | $7700.00 | Window Closed / Lapsed |