Speaker diaphragm molded from poly-biphenol phthalate type resin film
US4173701A · kind A · utility
5Cited by
0References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 26, 1977 |
| Grant date | Nov 6, 1979 |
| Priority date | — |
| Expiry date | Sep 26, 1997 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R7/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A speaker diaphragm molded from a poly-bisphenol phthalate type plastic film having ester linkages prepared from an aromatic dicarboxylic acid such as isophthalic acid or terephthalic acid or a mixture thereof and a bifunctional phenol such as bisphenol A. This speaker diaphragm has an excellent low-pitched sound reproducing performance and is further featured by the flat acoustic pressure-frequency characteristic and improved transduce efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.