| 摘要 |
The article (1') is made from a polymeric composition comprising a polyester resin and silica particles dispersed in the polyester resin, and comprises an unstreched portion (4) and a stretched wall (2'a). The silica particle concentration is not more than 40wt%, and:
(i) the density density (db) of the stretched wall (2'a) is at least 13% less than the density (dp) of the unstreched portion (4)
and/or
(ii) the thickness (WTb) of the stretched wall (2'a) is less than 0.5mm and the light transmission of the stretched wall (2'a) is less than 5% at 800nm and less than 2% at 550nm. |
