Solventless resin composition having minimal reactivity at room temperature
US5618891A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 29, 1995 |
| Grant date | Apr 8, 1997 |
| Priority date | — |
| Expiry date | Mar 29, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T442/2475
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A resin composition is provided that is suitable for impregnating sheet material, including fabrics, films, paper and tapes of the type employed to form prepregs, such as tapes used to form electrical insulation layers on electrical components. The resin composition includes a solid or semi-solid epoxy resin having an epoxide functionality of at least 2.5, a metal acetylacetonate for catalyzing the epoxy resin, and an accelerator of bisphenol A-formaldehyde novolac catalyzed by an acidic catalyst and having a hydroxyl equivalent weight of 120. The resin composition is essentially unreactive at room temperature and at elevated temperatures sufficient to enable permeation of the sheet material by the resin in its manufacture, is essentially unreactive at temperatures required to remove moisture and volatiles during processing of articles wrapped or taped with the sheet material, and cures at a higher temperature without adversely affecting the cure characteristics of the resin composition. The resin composition of this invention achieves the desirable reactivity characteristics noted above, while exhibiting enhanced mechanical, thermal and electrical properties necessary for its use …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.