This invention relates to 1,4-diketopyrrolo[3,4c]-pyrrole pigments of the formula characterized by desirable color properties and novel visible absorbance spectra with a steep slope on the bathochromic side of the absorption maximum in the range of from 500 to 650 nm. ...http://www.google.es/patents/US6911074?utm_source=gb-gplus-sharePatente US6911074 - Pigments having improved coloristic properties and process for their preparation
Pigments having improved coloristic properties and process for their preparation
