Patent ID: 8029891

Claim:
A method of making a polymer blend comprising the steps of: combining a polymeric matrix material and inorganic infrared absorbing nanoparticles via a high-shear melt mixing process to form a nanoparticulate solar control concentrate; providing a polymeric resin; and combining the nanoparticulate solar control concentrate and the polymeric resin to form the polymer blend; wherein the nanoparticulate solar control concentrate comprises a. about 70 wt % to about 50 wt % of the polymeric matrix material; and b. about 30 wt % to about 50 wt % of the inorganic infrared absorbing nanoparticles, said inorganic infrared absorbing nanoparticles having a nominal particle size of less than about 30 nm, and said inorganic infrared absorbing nanoparticles comprising antimony tin oxide, indium tin oxide, or a mixture of antimony tin oxide and indium tin oxide; wherein the weight percentages of the polymeric matrix material and of the inorganic infrared absorbing nanoparticles are based on the combined weight of the inorganic infrared absorbing nanoparticles and the polymeric matrix material.