Patent US3669910A successfully refreshed from Google Patents.
US3669910A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of foams
Assignee: Imperial Chemical Industries Ltd
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Filing: 1971-02-22
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Granted: 1972-06-13
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Expires: 1991-02-22
Abstract
Abstract Manufacture of rigid polyamide foams by producing a foam of molten polyamide in presence of a non-ionic surface active agent, especially an alkylene oxide condensate with an alkanol, alkylamine or alkylphenol containing 10 to 20 carbon atoms, and then cooling below the melting point to solidify the polyamide.
Inventors
- 👤 Geoffrey English
- 👤 Brian Arthur Mountfield
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 09:48
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08J2377/00
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
28 words
Process according to claim 1 wherein the non-ionic surface active agent is an alkylene oxide condensate with an alkanol, alkylamine or alkylphenol containing 10 to 20 carbon atoms.
Claim 2
Dependent Claim
17 words
Process according to claim 2 wherein the condensate contains from 1 to 5 moles of alkylene oxide.
Claim 3
Dependent Claim
26 words
Process according to claim 2 wherein the non-ionic surface active agent is a condensate of cetyl alcohol with from 1 to 5 moles of ethylene oxide.
Claim 4
Dependent Claim
26 words
Process according to claim 2 wherein the surface active agent consists essentially of a condensate of cetylamine with from 1 to 5 moles of ethylene oxide.
Claim 5
Dependent Claim
13 words
Process according to claim 1 wherein the blowing agent is a depolymerizable polymer.
Claim 6
Dependent Claim
23 words
Process according to claim 1 wherein the polyamide is selected from the class consisting of homopolymers and copolymers of caprolactam and hexamethylenediamine adipate.
Claim 7
Dependent Claim
23 words
Process according to claim 1 wherein the polyamide is selected from the class consisting of homopolymers and copolymers of caprolactam and hexamethylenediamine adipate.
Claim 8
Dependent Claim
27 words
Process according to claim 8 wherein the depolymerizable polymer is one of which the monomers recombine to form the polymer on cooling again below the ceiling temperature.
Claim 9
Dependent Claim
11 words
Process according to claim 8 wherein the depolymerizable polymer is polymethylmethacrylate.
Claim 10
Dependent Claim
16 words
Process according to claim 8 wherein the surface active agent is a siloxane/alkylene oxide block copolymer.
Claim 11
Dependent Claim
13 words
Process according to claim 1 carried out in presence of a polymerization catalyst.
Claim 12
Dependent Claim
12 words
Process according to claim 12 wherein the polymerization catalyst is cyclohexylphosphonic acid.
Claim 13
Dependent Claim
16 words
Process according to claim 12 wherein the polyamide has a molecular weight of 1,000 to 5,000.
Claim 14
Dependent Claim
17 words
Process according to claim 1 carried out in presence of a cross linking agent for the polyamide.
Claim 15
Dependent Claim
17 words
Process according to claim 15 wherein the cross linking agent is the bishexamethylenetriamine/adipic acid 2:3 molar complex.
Claim 16
Dependent Claim
17 words
Process according to claim 1 wherein the cross linking agent is the hydroxyhexamethylenediamine/adipic acid 1:1 molar complex.
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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) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |