US4088637A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of polycondensates containing imide groups
Assignee: Bayer AG
•
Filing: 1976-09-22
•
Granted: 1978-05-09
•
Expires: 1996-09-22
Abstract
Abstract A process for the production of polyimides by the condensation of cyclic polycarboxylic acid anhydrides with polyisocyanates and isocyanurates substituted with masked isocyanate groups in the presence of lactams or polyols, and the production of coatings on metals, in particular of lacquers on wires, and of films thereof.
Inventors
- 👤 Wilfried Zecher
- 👤 Willi Dunwald
- 👤 Rudolf Merten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:15
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/14; C08G18/00; C08G18/06; C08G18/28; C08G18/2805; C08G18/285; C08G18/2855; C08G18/30; C08G18/34; C08G18/343; C08G73/16
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
60 words
In the process for the production of a polycondensate coupled through imide groups by condensing a polycarboxylic acid anhydride with a polyisocyanate and a member selected from the group consisting of a lactam and a polyol, the improvement wherein 1 - 60% of the total quantity of isocyanate is in the form of an isocyanurate substituted with masked isocyanate groups.
Claim 2
Dependent Claim
60 words
In the process for the production of a polycondensate coupled through imide groups by condensing a polycarboxylic acid anhydride with a polyisocyanate and a member selected from the group consisting of a lactam and a polyol, the improvement wherein 1 - 60% of the total quantity of isocyanate is in the form of an isocyanurate substituted with masked isocyanate groups.
Claim 3
Dependent Claim
27 words
A process as claimed in claim 1, wherein the lactam or polyol taking part in the polycondensation is also used to in situ mask the isocyanate groups.
Claim 4
Dependent Claim
15 words
A process according to claim 1, wherein the lactam has at least 4 ring members.
Claim 5
Dependent Claim
20 words
A process as claimed in claim 1, wherein the polycondensation takes place at temperature of from 0° to 450° C.
Claim 6
Dependent Claim
18 words
A process as claimed in claim 1, wherein the polycondensation takes place in the presence of a catalyst.
Claim 7
Dependent Claim
11 words
A polycondensate prepared by a process as claimed in claim 1.
Claim 8
Dependent Claim
12 words
A metal substrate lacquered with a polycondensate as claimed in claim 6.
Claim 9
Dependent Claim
11 words
A wire lacquered with a polycondensate as claimed in claim 6.
Claim 10
Dependent Claim
49 words
A process as claimed in claim 1, wherein the polycarboxylic acid anhydride is a cyclic carboxylic acid anhydride compound substituted by at least one substituent selected from the group consisting of another cyclic anhydride group, a carboxyl group, a carbalkoxy group, a carbaroxy group of SO 3 H group.
Claim 11
Dependent Claim
41 words
A process as claimed in claim 1, wherein the isocyanate groups of the isocyanurate are masked with a member selected from the group consisting of lactam having at least 4 ring members, an aliphatic mono-hydroxy compound and an aromatic mono-hydroxy compound.
Claim 12
Dependent Claim
15 words
A process as claimed in claim 1, wherein the aromatic mono-hydroxy compound is a phenol.
Claim 13
Dependent Claim
86 words
A process as claimed in claim 1, wherein polyisocyanates of the general formula R.sup.2 (--NCO).sub.z are used in which R 2 represents alkyl having from 1 to 20 C-atoms, aryl having from 6 to 12 C-atoms, cycloalkyl having from 5 to 12 C-atoms, alkaryl having from 7 to 20 C-atoms, and heteroaryl or hetero-cycloalkyl having from 5 to 12 C-atoms and wherein the hetero atom is selected from the group consisting of nitrogen, oxygen and sulfur, and z is a whole number from 2 to 4.
Claim 14
Dependent Claim
41 words
A process as claimed in claim 12, wherein the polyisocyanate is selected from the group consisting of toluylene-diisocyanates, m-phenylene diisocyanate, phosgenated condensates of aniline and formaldehyde having a polyphenylene-methylene structure, 4,4'-diisocyanato-diphenylmethane, 4,4'-diisocyanatodiphenylether, p-phenylene diisocyanate, 4,4'-diisocyanato-diphenyldimethylmethane, aliphatic hexamethylene diisocyanate and isophorone diisocyanate.
Claim 15
Dependent Claim
39 words
A process as claimed in claim 1, wherein a polyol is used, said polyol being selected from the group consisting of alkanols having at least two OH groups in the molecule and oligomeric polyesters having at least 3% OH.
References Cited (Backward Citations)
US3560446A
Cited
US3697480A
Cited
US3652424A
Cited
US3666725A
Cited
US3822240A
Cited
US3748315A
Cited
US3893978A
Cited
US3896089A
Cited
US3996223A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-08 | 1981-11-07 | 1982-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-08 | 1985-11-07 | 1986-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-08 | 1989-11-07 | 1990-05-09 | $7700.00 | Window Closed / Lapsed |