US4419294A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Carbodiimide oligomers of tertiary aliphatic isocyanates
Assignee: Wyeth Holdings LLC
•
Filing: 1982-03-08
•
Granted: 1983-12-06
•
Expires: 2002-03-08
Abstract
Abstract Tertiary aliphatic diisocyanate carbodiimide oligomers useful in the formulation of light stable urethane spray coatings prepared by catalytic conversion of diisocyanate monomers such as tetramethylxylylene diisocyanates and dipentene diisocyanate.
Inventors
- 👤 Allan M. Feldman
- 👤 Peter S. Forgione
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:33
CPC Classifications
C; C07; C07C; C07C267/00; C07C2601/00; C07C2601/12; C07C2601/14
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
37 words
A stable, liquid diisocyanate consisting essentially of a mixture of oligomers of the formula O═C═N--[R--N═C═N].sub.n --R--N═C═O wherein n is an integer from 1 to 10 and R represents a divalent hydrocarbon group having tertiary terminal carbon atoms.
Claim 2
Dependent Claim
37 words
A stable, liquid diisocyanate consisting essentially of a mixture of oligomers of the formula O═C═N--[R--N═C═N].sub.n --R--N═C═O wherein n is an integer from 1 to 10 and R represents a divalent hydrocarbon group having tertiary terminal carbon atoms.
Claim 3
Dependent Claim
11 words
A diisocyanate according to claim 1 in which R is ##STR3##
Claim 4
Dependent Claim
11 words
A diisocyanate according to claim 1 in which R is ##STR4##
Claim 5
Dependent Claim
11 words
A diisocyanate according to claim 1 in which R is ##STR5##
Claim 6
Independent Claim
57 words
A method for producing diisocyanate oligomers having carbodiimide linkages which comprises polymerizing a tertiary aliphatic diisocyanate in the presence of a volatile catalyst and at a temperature effective to produce such oligomers and carbondioxide while monitoring the amount of monomer, and separating the oligomers from catalyst and unreacted monomer at a predetermined minimum level of unreacted monomer.
Claim 7
Independent Claim
57 words
A method for producing diisocyanate oligomers having carbodiimide linkages which comprises polymerizing a tertiary aliphatic diisocyanate in the presence of a volatile catalyst and at a temperature effective to produce such oligomers and carbondioxide while monitoring the amount of monomer, and separating the oligomers from catalyst and unreacted monomer at a predetermined minimum level of unreacted monomer.
Claim 8
Dependent Claim
14 words
A process according to claim 5 in which the diisocyanate is a tetramethylxylylene diisocyanate.
Claim 9
Dependent Claim
13 words
A process according to claim 6 in which the diisocyanate is p-tetramethylxylylene diisocyanate.
Claim 10
Dependent Claim
13 words
A process according to claim 6 in which the diisocyanate is m-tetramethylxylylene diisocyanate.
Claim 11
Dependent Claim
13 words
A process according to claim 5 in which the diisocyanate is dipentene diisocyanate.
References Cited (Backward Citations)
US4120884A
Cited
US4143063A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-05 | 1987-06-06 | 1987-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-05 | 1991-06-06 | 1991-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-05 | 1995-06-06 | 1995-12-06 | $7700.00 | Window Closed / Lapsed |