Curable polycycloolefin resin solutions, their use in making printed circuit boards and the boards so made
US5274026A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 23, 1988 |
| Grant date | Dec 28, 1993 |
| Priority date | — |
| Expiry date | Sep 23, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/032
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Curable polycycloolefin resin solutions having particular utility in the fabrication of printed circuit boards are disclosed. A solvent soluble polymer is typically solution polymerized from norbornene-type monomers in the presence of a metathesis catalyst package. This polymer may then be purified by precipitation and redissolution. A curing agent, such as a high activation temperature peroxide can then be added to the solution and then this curing agent containing solution can be used to impregnate a suitable substrate such as a fiberglass cloth. The impregnated substrate can then be dried, preferably at temperatures above the glass transition temperature of the polycycloolefin but below the activation temperature of the curing agent. Then one or more prepregs can be stacked and laminated to conductive foil at a temperature high enough to activate the curing agent. Printed circuit boards are obtained which have good resistance to organic solvents such as methylene chloride and to molten solder and which also display good electrical properties such as dielectric constant less than about 3.5 at 1 MHz and a dissipation constant less than about 0.005 at 1 MHz.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.