COMPOSITION CHANGING COLOR AND METHODS OF ITS USAGE Russian patent published in 2000 - IPC

FIELD: optics. SUBSTANCE: painted composition includes absorber of ultraviolet radiation, substance forming molecular inclusions and having structure with one cavity as minimum and dye changing its color irreversibly under ultraviolet radiation. Toner for electro-photographic process can carry mentioned painted composition and carrier. In general case ultraviolet radiation has wave length of 100-375 nm and presents noncoherent pulse ultraviolet radiation from discharge lamp with dielectric barrier. Dye and absorber of ultraviolet radiation can be related to substance forming molecular inclusions. In this case this dye can be encapsulated at least partially in cavity of substance forming molecular inclusions. Dye can be covalently tied up with absorber of ultraviolet radiation. Backing with applied pattern can be formed with the aid of painted composition. Absorber of ultraviolet radiation includes sensitizer selectively absorbing radiation and photographic initiator. EFFECT: provision for simple ecologically pure method of re-processing of paper for its multiple usage. 77 cl, 5 dwg, 6 tbl