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Patent US3966656A successfully refreshed from Google Patents.
US3966656A
Expired / Lapsed
US
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Aqueous organic base solution of polyhydrazides
Assignee: EIDP Inc
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Filing: 1974-09-23
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Granted: 1976-06-29
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Expires: 1994-09-23
Abstract
Abstract This invention relates to novel film- and fiber-forming polyhydrazide solutions (dopes) which are prepared in a solvent system comprising aqueous organic bases. Some dopes of this invention are optically anisotropic.
Inventors
- 👤 Jon David Hartzler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 20:33
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
74 words
A film and/or fiber forming solution comprising a (co)polyhydrazide in an aqueous solution of an organic base selected from the group consisting of tetramethylammonium hydroxide, and tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and the (co)polyhydrazide being characterized by substantially equimolar amounts of repeating structural units of the formulae ##EQU3## wherein R 1 and R 2 represent divalent radicals individually selected from the group of organic radicals of 1-12 carbon atoms, 2,5-pyridinediyl radicals, or a chemical bond.
Claim 2
Dependent Claim
74 words
A film and/or fiber forming solution comprising a (co)polyhydrazide in an aqueous solution of an organic base selected from the group consisting of tetramethylammonium hydroxide, and tetraethylammonium hydroxide, tetrapropylammonium hydroxide, and the (co)polyhydrazide being characterized by substantially equimolar amounts of repeating structural units of the formulae ##EQU3## wherein R 1 and R 2 represent divalent radicals individually selected from the group of organic radicals of 1-12 carbon atoms, 2,5-pyridinediyl radicals, or a chemical bond.
Claim 3
Dependent Claim
17 words
The solution of claim 1 wherein the (co)polyhydrazide has an inherent viscosity of at least about 0.2.
Claim 4
Dependent Claim
22 words
A solution according to claim 2 comprising 5-35% (co)polyhydrazide in an aqueous solution of tetramethylammonium hydroxide at a base concentration of 2-30%.
Claim 5
Dependent Claim
16 words
A solution according to claim 3 containing from 5-28% of the (co)polyhydrazide, said solution being anisotropic.
Claim 6
Dependent Claim
22 words
A solution according to claim 2 comprising 5-10% (co)polyhydrazide in an aqueous solution of tetraethylammonium hydroxide at a base concentration of 2-10%.
Claim 7
Dependent Claim
12 words
A solution according to claim 4 wherein the polyhydrazide is poly(terephthalic hydrazide).
Claim 8
Dependent Claim
61 words
A film or fiber-forming solution of a (co)polyhydrazide in an aqueous solution of an organic base selected from the group consisting of tetramethylammonium hydroxide, tetraethylammonium hydroxide and tetrapropylammonium hydroxide, the (co)polyhydrazide being characterized by substantially equimolar amounts of repeating structural units of the formulae ##EQU4## wherein R 1 and R 2 represent divalent radicals individually selected from the group of ##SPC9##
Claim 9
Dependent Claim
61 words
A film or fiber-forming solution of a (co)polyhydrazide in an aqueous solution of an organic base selected from the group consisting of tetramethylammonium hydroxide, tetraethylammonium hydroxide and tetrapropylammonium hydroxide, the (co)polyhydrazide being characterized by substantially equimolar amounts of repeating structural units of the formulae ##EQU4## wherein R 1 and R 2 represent divalent radicals individually selected from the group of ##SPC9##
Claim 10
Dependent Claim
13 words
A solution according to claim 7 wherein the formula (I) unit is ##EQU5##
References Cited (Backward Citations)
US3842028A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |