White light-shielding compositions and articles comprising same
US7928168B2 · kind B2 · utility
10Cited by
8References
22Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2007 |
| Grant date | Apr 19, 2011 |
| Priority date | — |
| Expiry date | May 16, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L83/10
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A polymer composition is provided which is white and opaque (i.e. shields from light). The polymer composition comprises a blend of (i) a silicon-free polycarbonate polymer and (ii) a polycarbonate-polysiloxane copolymer; a whitener such as titanium dioxide; and (iii) a non-white colorant such as carbon black. The resulting composition, when molded and measured at a thickness of 0.75 mm, has an L* of greater than 80 and a % T of less than 1%. The composition also has good impact strength at low temperatures and good stability during processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.