Effects of fluorination on the properties of organic pigments

The solid state properties of two fluorinated pigments are compared with th eir unfluorinated analogues and the influence of fluoro substitution upon t he solid state properties is discussed. The effect of fluorination was exam ined by a range of techniques including UV/visible spectroscopy, solid stat e NMR spectroscopy and powder X-ray diffraction. Fluorination modified the crystal packing of the molecules and subsequently altered the pigmentary pe rformance of the compounds. In both cases fluorination gave rise to compoun ds with poorer fastness properties. (C) 1999 Elsevier Science Ltd. All righ ts reserved.