Patent US1978161A successfully refreshed from Google Patents.
Patent US4130697A successfully refreshed from Google Patents.
US4130697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of foamed plastics with improved combustion characteristics
Assignee: Patheon Austria GmbH and Co KG
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Filing: 1977-07-26
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Granted: 1978-12-19
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Expires: 1997-07-26
Abstract
Abstract Foamed plastics with improved combustion characteristics are produced by condensing an aqueous solution of formaldehyde-urea and/or melamine precondensates with polyisocyanates and optionally a polyol in the presence of an acid catalyst, being present in an amount of 1 part by weight per at least 20 parts by weight of precondensate, whereby this catalyst is added to the isocyanate before mixing with the precondensate or to the mixture of isocyanate and precondensate, but separately from the precondensate.
Inventors
- 👤 Gerhard Stern
- 👤 Karlheinz Wegleitner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:12
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/54; C08G18/544; C08G18/08; C08G18/16; C08G18/166
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
145 words
In a process for production foamed plastics with improved combustion characteristics by a condensation reaction of aminoplast resins with isocyanates which are at least bifunctional, the improvement comprising using as starting material an aqueous solution of a precondensate of formaldehyde with an aminoplast forming compound selected from the group consisting of urea and melamine, which solution contains from 0.5 to 20 parts by weight of the precondensate per part by weight of water, adding to the isocyanate or its mixture with the aqueous solution of the precondensate but separately from the solution of the precondensate an acid catalyst in an amount of 1 part by weight per at least 20 parts by weight of the precondensate and condensing the precondensate with the isocyanate at temperatures of between 20° to 100° C., whereby the weight ratio of precondensate to isocyanate used is from 0.20 to 15:1.
Claim 2
Dependent Claim
145 words
In a process for production foamed plastics with improved combustion characteristics by a condensation reaction of aminoplast resins with isocyanates which are at least bifunctional, the improvement comprising using as starting material an aqueous solution of a precondensate of formaldehyde with an aminoplast forming compound selected from the group consisting of urea and melamine, which solution contains from 0.5 to 20 parts by weight of the precondensate per part by weight of water, adding to the isocyanate or its mixture with the aqueous solution of the precondensate but separately from the solution of the precondensate an acid catalyst in an amount of 1 part by weight per at least 20 parts by weight of the precondensate and condensing the precondensate with the isocyanate at temperatures of between 20° to 100° C., whereby the weight ratio of precondensate to isocyanate used is from 0.20 to 15:1.
Claim 3
Dependent Claim
22 words
A process according to claim 1, in which a polyolcompound is also added to the isocyanate or its mixture with the precondensate.
Claim 4
Dependent Claim
14 words
A process according to claim 1, in which the isocyanate used is tolylene diisocyanate.
Claim 5
Dependent Claim
14 words
A process according to claim 1, in which the isocyanate employed is diphenylmethane diisocyanate.
Claim 6
Dependent Claim
17 words
A process according to claim 1, in which the ratio of precondensate:polyisocyanate is from 1 to 13:1.
Claim 7
Dependent Claim
15 words
A process according to claim 1, in which the acid catalyst used is phosphoric acid.
Claim 8
Dependent Claim
15 words
A process according to claim 1, in which the acid catalyst used is phosphorus trichloride.
Claim 9
Dependent Claim
15 words
A process according to claim 1, in which the acid catalyst used is ammonium chloride.
Claim 10
Dependent Claim
26 words
A process according to claim 2, in which the polyol is added to the reaction mixture in a weight ratio of polyol:isocyanate of 1 to 15:1.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-12-18 | 1982-06-19 | 1982-12-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-12-18 | 1986-06-19 | 1986-12-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-12-18 | 1990-06-19 | 1990-12-19 | $7700.00 | Window Closed / Lapsed |