CPC F21V 3/0625 (2018.02) [C08L 33/12 (2013.01); F21Y 2115/10 (2016.08)] | 18 Claims |
1. A translucent, light-diffusing thermoplastic article comprising a blend composition of
a) a thermoplastic polymer matrix material, wherein said polymer matrix is selected from the group consisting of crystal polystyrene, polyethylene terephthalate (PET), a transparent or translucent polyolefin, transparent or translucent polypropylene, a transparent or translucent polyamide, glycol modified polyethylene terephthalate (PETG), poly(methylmethacrylate styrene) copolymer p(MMA-co-STY), styrene acrylonitrile (SAN), polyvinyl chloride, polycarbonate, and copolymers and mixtures thereof,
b) from 0.01 to 5.8 weight percent of organic polymer diffusing particles that are refractive index (R.I.) mis-matched to the matrix polymer, wherein the absolute difference between the matrix polymer R.I. and the diffusing organic polymer particles R.I. is from greater than 0.02 to 0.15,
c) optionally from 0 to 15 weight percent of inorganic diffusing particles,
wherein said weight percentage is based on the weight of the total blend composition,
wherein, when said article comprising said blend composition is a sheet or film, said sheet or film has a luminous transmission of greater than 40%, an optical haze of greater than 95% and a diffuse light scattering of greater than 85%,
and wherein the organic particles are selected to provide a calculated transmittance (I/I0) of less than 0.5 calculated for a sample of 3 mm thickness and a λ=550 nm;
and wherein said composition further comprises one or more optical brighteners, wherein said optical brighteners are selected from nano-sized zinc oxide compounds and zinc borate.
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