US4001180A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethane curing agent
Assignee: Individual
•
Filing: 1975-02-27
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Granted: 1977-01-04
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Expires: 1995-02-27
Abstract
Abstract A new curing agent for the production of polyurethane elastomers, particularly for use at processing temperatures of from about ambient up to about 250° F is disclosed. The new curing agent is the polyfunctional (including difunctional) reaction product of methylene bis (methyl anthranilate) and from about 0.025 to about 0.1 equivalents of an isocyanate-terminated prepolymer containing from 2 to about 10 percent excess isocyanate groups. Other components including a saturated monocarboxylic acid of from 2 to about 31 carbon atoms, another diamine compound (e.g., diamino diphenyl sulfone) or a polyfunctional hydroxyl group-containing compound may be incorporated into the curing agent.
Inventors
- 👤 Earl N. Doyle
- 👤 Anna W. Crull
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:08
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/16; C08G18/166; C08G18/168; C08G18/089; C08G18/10
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
40 words
A polyfunctional curing agent for polyurethane elastomers comprising the reaction product of methylene bis (methyl anthranilate) and from about 0.025 to about 0.1 equivalents of an isocyanate-terminated prepolymer containing from about 2 to about 10 mole percent excess isocyanate groups.
Claim 2
Dependent Claim
40 words
A polyfunctional curing agent for polyurethane elastomers comprising the reaction product of methylene bis (methyl anthranilate) and from about 0.025 to about 0.1 equivalents of an isocyanate-terminated prepolymer containing from about 2 to about 10 mole percent excess isocyanate groups.
Claim 3
Dependent Claim
32 words
The polyfunctional curing agent of claim 1 wherein the curing agent is the reaction product of methylene bis (methyl anthranilate) and from about 0.03 to about 0.06 equivalents of the said prepolymer.
Claim 4
Dependent Claim
29 words
The polyfunctional curing agent of claim 1 further including from about 0.05 to about 0.1 equivalents of a saturated monocarboxylic acid having from 2 to about 31 carbon atoms.
Claim 5
Dependent Claim
20 words
The polyfunctional curing agent of claim 3 further including from about 0.05 to about 0.1 equivalents of an aromatic diamine.
Claim 6
Dependent Claim
28 words
The polyfunctional curing agent of claim 4 wherein said further aromatic diamine will not remain in eutectic solution with methylene bis(methyl anthranilate) in the absence of said acid.
Claim 7
Dependent Claim
22 words
The polyfunctional curing agent of claim 1 further including from about 0.1 to about 0.3 equivalents of a polyfunctional hydroxyl group-containing compound.
Claim 8
Dependent Claim
22 words
The polyfunctional curing agent of claim 6 further including from about 0.1 to about 0.2 equivalents of a polyfunctional hydroxyl group-containing compound.
Claim 9
Dependent Claim
47 words
The polyfunctional curing agent of claim 7 wherein said hydroxy group - containing compound is a relatively high melting point crystalline polyol which when partially reacted with said isocyanate-terminated prepolymer, after melting, does not recrystallize when cooled to a temperature of betwen about 150° and 225° F.
Claim 10
Dependent Claim
24 words
A process for forming a polyurethane comprising mixing an isocyanate-terminated polyurethane prepolymer composition and the curing agent of claim 1 and curing the mixture.
Claim 11
Dependent Claim
21 words
The process of claim 9 wherein the curing is performed at a temperature of from about ambient to about 250° F.
Claim 12
Dependent Claim
21 words
The process of claim 10 wherein the curing is performed at a temperature of from about 200° to about 230° F.
Claim 13
Dependent Claim
8 words
The polyurethane of the process of claim 9.
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) | 1980-01-04 | 1980-07-05 | 1981-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-04 | 1984-07-05 | 1985-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-04 | 1988-07-05 | 1989-01-04 | $7700.00 | Window Closed / Lapsed |