TETRABENZODIAZADIKETOPERYLENE PIGMENTS FOR LASER MARKING

摘要

A method for laser marking a substrate which method comprises exposing a composition comprising a tetrabenzodiazadiketoperylene pigment to laser radiation or heat to produce a fluorescent marking readily apparent under UV light is disclosed. This method can yield fluorescent markings which are not readily apparent under ambient light. A method for producing non-fluorescent marks on substrates containing fluorescent tetrabenzodiazadiketoperylene dyes by laser exposure is also disclosed.