Radiation stress relieving of sulfone polymer articles
US4339303A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1981 |
| Grant date | Jul 13, 1982 |
| Priority date | — |
| Expiry date | Jan 12, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24322
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of rapidly relieving stress in an article comprised of a sulfone polymer is disclosed. The method can be used in the preparation of printed circuit boards. An article comprised of a sulfone polymer is exposed to electromagnetic radiation, for a time period sufficient to absorb enough energy to stress relieve the sulfone polymer against stress cracking therein. Exposure occurs at one or more ranges of frequencies which are capable of being absorbed by the sulfone polymer and which are effective for stress relieving without or substantially without causing heat induced softening or flowing of the sulfone polymer. The electromagnetic radiation is selected from the ranges of infrared, microwave and ultraviolet radiation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.