Patent US4497944A successfully refreshed from Google Patents.
US4497944A
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US
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Process for producing polyamide-imide resin
Assignee: Resonac Corp
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Filing: 1982-11-04
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Granted: 1985-02-05
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Expires: 2002-11-04
Abstract
Abstract A polyamide-imide resin which can give a varnish having a high resin content, excellent in storage stability and heat resistant final products such as insulated wire can be produced by reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in the presence of a basic solvent while adjusting the resin content at 40% by weight or more, and adding a compound having one active hydrogen atom before, during or after the above-mentioned reaction so as to adjust the reduced viscosity of the resin to 0.27 or lower.
Inventors
- 👤 Hiroshi Nishizawa
- 👤 Yoshiyuki Mukoyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 14:24
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/14; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/303; H01B3/306
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
88 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom selected from the group consisting of a lactam, a lactam and an oxime, and a lactam and an alcohol before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 2
Dependent Claim
88 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom selected from the group consisting of a lactam, a lactam and an oxime, and a lactam and an alcohol before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 3
Dependent Claim
16 words
A process according to claim 1, wherein the aromatic diisocyanate is 4,4'-diphenylmethane diisocyanate or tolylene diisocyanate.
Claim 4
Dependent Claim
14 words
A process according to claim 2, wherein the tricarboxylic acid anhydride is trimellitic anhydride.
Claim 5
Dependent Claim
12 words
A process according to claim 3, wherein the basic solvent is N-methylpyrrolidone.
Claim 6
Dependent Claim
88 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom selected from the group consisting of a lactam, an alcohol, an imide, an oxime, and imine, and an oxazoline, before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 7
Dependent Claim
88 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom selected from the group consisting of a lactam, an alcohol, an imide, an oxime, and imine, and an oxazoline, before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 8
Dependent Claim
27 words
A process according to claim 1, wherein 0.1 to 1.5 moles of the compound having one active hydrogen atom is used per mole of the aromatic diisocyanate.
Claim 9
Dependent Claim
64 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one lactam before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 10
Dependent Claim
64 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one lactam before, during or after the reaction to adjust the reduced viscosity of the resin to 0.27 or lower.
Claim 11
Dependent Claim
42 words
A process according to claim 1, wherein the compound having one active hydrogen atom is added before or during the reaction of the aromatic diisocyanate and the tricarboxylic acid anhydride and conducting the reaction at a temperature of 80° to 200° C.
Claim 12
Dependent Claim
85 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom, except for phenolic compounds after the reaction of the aromatic diisocyanate and the tricarboxylic acid anhydride, and allowing the at least one compound to react at 0° to 130° C. up to 7-8 hours.
Claim 13
Dependent Claim
85 words
A process for producing a polyamide-imide resin which comprises: reacting an aromatic diisocyanate with a tricarboxylic acid anhydride in approximately equimolar amounts in the presence of a basic solvent, while adjusting the resin content at 40% by weight or more, and adding at least one compound having one active hydrogen atom, except for phenolic compounds after the reaction of the aromatic diisocyanate and the tricarboxylic acid anhydride, and allowing the at least one compound to react at 0° to 130° C. up to 7-8 hours.
Claim 14
Dependent Claim
21 words
A process according to claim 1, wherein the basic solvent is selected from the group consisting of N-methylpyrrolidone, dimethylformamide, and dimethylacetamide.
Claim 15
Dependent Claim
18 words
A process according to claim 1, wherein the resin content is adjusted to 40 to 80% by weight.
Claim 16
Dependent Claim
11 words
A process according to claim 7, wherein the lactam is ε-caprolactam.
Claim 17
Dependent Claim
27 words
A process according to claim 7, wherein the compound having one active hydrogen atom is a lactam selected from the group consisting of 2-pyrrolidone, ε-caprolactam, and lauryllactam.
Claim 18
Dependent Claim
17 words
A process according to claim 6, wherein the compound having one active hydrogen atom is a lactam.
Claim 19
Dependent Claim
27 words
A process according to claim 6, wherein the compound having one active hydrogen atom is a lactam selected from the group consisting of 2-pyrrolidone, ε-caprolactam, and lauryllactam.
Claim 20
Dependent Claim
27 words
A process according to claim 8, wherein 0.1 to 1.5 moles of the compound having one active hydrogen atom is used per mole of the aromatic diisocyanate.
Claim 21
Dependent Claim
17 words
A process according to claim 16, wherein the compound having one active hydrogen atom is a lactam.
Claim 22
Dependent Claim
27 words
A process according to claim 16, wherein the compound having one active hydrogen atom is a lactam selected from the group consisting of 2-pyrrolidone, ε-caprolactam and lauryllactam.
Claim 23
Dependent Claim
27 words
A process according to claim 9, wherein 0.1 to 1.5 moles of the compound having one active hydrogen atom is used per mole of the aromatic diisocyanate.
Claim 24
Dependent Claim
17 words
A process according to claim 19, wherein the compound having one active hydrogen atom is a lactam.
Claim 25
Dependent Claim
27 words
A process according to claim 19, wherein the compound having one active hydrogen atom is a lactam selected from the group consisting of 2-pyrrolidone, ε-caprolactam and lauryllactam.
References Cited (Backward Citations)
US4354965A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-05 | 1988-08-06 | 1989-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-05 | 1992-08-06 | 1993-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-05 | 1996-08-06 | 1997-02-05 | $7700.00 | Window Closed / Lapsed |