Hardening phenol-formaldehyde resols in the presence of aniline
US4555544A · kind A · utility
10Cited by
19References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 28, 1984 |
| Grant date | Nov 26, 1985 |
| Priority date | — |
| Expiry date | Dec 28, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31942
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
In a process for hardening phenol-formaldehyde resol resins, comprising conducting the hardening of the resins with an acidic solution of water and/or an organic solvent having dissolved therein an aromatic sulphonic acid and/or concentrated sulphuric acid, the improvement comprising the hardening in the presence of aniline added to the phenolic resin beforehand in a quantity of between about 0.5 and 2% relative to the weight of the phenolic resin whereby the pot life is extended and the cure time is satisfactory, the resultant products being especially useful as prepegs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.