Method of making cellular polymeric shaped articles having relief patterns
US3949028A · kind A · utility
28Cited by
2References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1974 |
| Grant date | Apr 6, 1976 |
| Priority date | — |
| Expiry date | Oct 23, 1994 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24661
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of making cellular or expanded polymeric shaped articles having relief patterns which comprises forming a thermoplastic polymer composition containing azodicarbonamide as a chemical blowing agent into a desired shape, irradiating a surface of the shaped body thus obtained with light of wave lengths of 100 to 500 m.mu. through a printed pattern applied thereto or a screen which locally shades light rays, such as a stencil or a positive or negative transparency, superposed thereon and heating the shaped body to effect foaming or expansion thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.