High reflectance polycarbonate

摘要

In an embodiment, a polycarbonate composition comprises: polycarbonate; 7 wt % to 20 wt % titanium dioxide, based upon a total weight of the polycarbonate composition; an optional flame retardant; and an optional UV stabilizer. A plaque formed from the polycarbonate composition has a reflectance of greater than or equal to 95%, as determined by reflectance measurements using a Gretag Macbeth Coloreye spectrophotometer (D65 light source, 10 degree observer, UV included) made at a wavelength of 680 nm. In an embodiment, a polycarbonate composition comprises: a polycarbonate; 7 to 20 wt % titanium dioxide; a flame retardant; and an optional UV stabilizer; wherein the polycarbonate composition has a maximum reflectance of greater than or equal to 95%. The melt volume rate as determined at 300° C. using a 1.2 kilogram weight, in accordance with ASTM D1238-04 is from 5 to 30 grams per 10 minutes.

主权项

1. An Illumination device, comprising:
an LED; a reflective surface, wherein the reflective surface comprises a composition comprising polycarbonate;
12.5 wt % to 15 wt % titanium dioxide, based upon a total weight of the polycarbonate composition;a flame retardant; andan optional UV stabilizer;wherein a plaque consisting essentially of the polycarbonate, the titanium dioxide, the flame retardant; and the optional UV stabilizer has a reflectance of greater than or equal to 96.5% as determined by reflectance measurements using a Gretag Macbeth Coloreye spectrophotometer (D65 light source, 10 degree observer, UV included) made at a wavelength of 680 nm;wherein a melt volume rate of the composition as determined at 300° C. using a 1.2kilogram weight, in accordance with ASTM D1238-04 is from 5 to 30 grams per 10 minutes; wherein, when in the form of a 1.5 mm bar, the composition achieves a UL94 V0 probability of first time pass of greater than or equal to 85%; and wherein, when in the form of a 3.00 mm plaque, the composition is able to achieve a UL94 5VA rating after 168 hours at 70° C. and after 48 hours at 23° C.; and a lens in physical contact with the reflector.