Patent US4937012A successfully refreshed from Google Patents.
US4937012A
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US
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Low temperature stable polymethylene polyphenylene polyisocyanates
Assignee: BASF Corp
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Filing: 1987-08-14
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Granted: 1990-06-26
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Expires: 2007-08-14
Abstract
Abstract Low temperature stable polymethylene polyphenylene polyisocyanates are composed of crude polymethylene polyphenylene polyisocyanate containing from about 50 to about 80 percent by weight 2-ring diphenylmethane diisocyanate wherein from about 65 to about 93 weight percent of the 2-ring diisocyanate is 4,4'- and from about 7 to about 35 weight percent is 2,4'- and furthermore the composition contains from about 1 to about 5 weight percent carbodiimide-uretonimine structure. The polyisocyanates are useful in preparing polyurethane foams.
Inventors
- 👤 Peter T. Kan
- 👤 John W. Lightsey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 09:48
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/70; C08G18/72; C08G18/77; C08G18/78; C08G18/79; C08G18/797; C07; C07D; C07D229/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
94 words
A polyisocyanate composition which is storage stable at temperatures of about 0° C. which composition consisting essentially of a crude polymethylene polyphenylene polyisocyanate containing from about 50 to 80 weight percent 2-ring diphenylmethane diisocyanate, wherein from about 7 to about 35 weight percent of the 2-ring diisocyanate is 2,4'-diphenylmethane diisocyanate, from about 65 to about 93 weight percent of the 2-ring diisocyanate is 4,4'-diphenylmethane diisocyanate and wherein the 2-ring diisocyanate contains from 1 to 5 weight percent uretonimine structure the remainder of said polyisocyanate composition comprising a polyisocyanate having a functionality greater than 2.
Claim 2
Dependent Claim
94 words
A polyisocyanate composition which is storage stable at temperatures of about 0° C. which composition consisting essentially of a crude polymethylene polyphenylene polyisocyanate containing from about 50 to 80 weight percent 2-ring diphenylmethane diisocyanate, wherein from about 7 to about 35 weight percent of the 2-ring diisocyanate is 2,4'-diphenylmethane diisocyanate, from about 65 to about 93 weight percent of the 2-ring diisocyanate is 4,4'-diphenylmethane diisocyanate and wherein the 2-ring diisocyanate contains from 1 to 5 weight percent uretonimine structure the remainder of said polyisocyanate composition comprising a polyisocyanate having a functionality greater than 2.
Claim 3
Dependent Claim
23 words
The polyisocyanate composition of claim 1 wherein the 2,4'-diphenylmethane diisocyanate is from about 7 to about 12 weight percent of the 2-ring diisocyanate.
Claim 4
Dependent Claim
19 words
The polyisocyanate composition of claim 1 wherein the 2-ring diisocyanate is from about 60 to about 70 weight percent.
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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) | 1993-06-25 | 1993-12-25 | 1994-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-25 | 1997-12-25 | 1998-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-25 | 2001-12-25 | 2002-06-26 | $7700.00 | Window Closed / Lapsed |