Patent ID: 7169222

Claim:
An agricultural film, comprising a multi-layer interference pigment comprising a transparent carrier material coated with a first layer of a high refractive index material, and thereon alternating layers of colorless low refractive index material then high refractive index material, the difference in refractive indices being at least 0.1,wherein the layers of high refractive index material consist of a non-absorbing colorless oxide or mixtures thereof, the pigment having high transmissibility in the visible region of light, and high reflectivity in the near infrared region, wherein the multilayer interference pigment is prepared by alternate coating of the transparent carrier material with a metal oxide of high refractive index and with a metal oxide of low refractive index in a wet process by hydrolysis of corresponding inorganic water-soluble metal compounds, separation, drying and optional calcination of resulting pigment, wherein the oxide of high refractive index consists of a non-absorbing colorless oxide or mixture of such oxides, and wherein the low refractive index material is colorless.