Patent ID: 7582156
Filing Date: 2009-09-01
Classification: B01J,C01G,C01P,C09C

Abstract:
1. A coating agent which produces a film with photocatalytic properties, comprising composite photocatalyst particles of titanium dioxide and a compound inactive as a photocatalyst, and at least a binder, wherein said photocatalyst particles achieve a ratio of decomposition of acetaldehyde (DWA) values of at least 80%, wherein said DWA value is measured after 3.5 g of said photocatalyst particles are spread uniformly across a flat surface of diameter 9 cm, placed within 5 L of dry air containing 20 ppm by volume of acetaldehyde, and irradiated for one hour with a day white fluorescent lamp producing an ultraviolet light intensity of 6 μW/cm wherein a BET specific surface area of said photocatalyst particles of titanium dioxide and a compound inactive as a photocatalyst is from 10 to 300 m wherein said compound inactive as a photocatalyst is present in a quantity of from 0.01 to 50 mass % based on a mass of said titanium dioxide, and wherein the photocatalyst particles of titanium dioxide and a compound inactive as a photocatalyst are produced by a method, comprising the steps of: preparing a water based slurry of pH 3 to 5 comprising titanium dioxide, preparing a water based solution comprising a compound inactive as a photocatalyst, and reacting said slurry and said water based solution together at a pH of 4 to 10.