Patent ID: 9169399
Filing Date: 2015-10-27
Classification: C01P,C09C,C09D,G01J,G01N

Abstract:
1. A method of characterising a scattering coloured pigment for use in the determination of the absorption and scattering coefficients of the scattering coloured pigment, the method comprising the step of: (i) preparing a white paste comprising a mixture of the scattering coloured pigment and a substantially non-absorbing scattering pigment at a plurality of different volume fractions, wherein the scattering coloured pigment is a large particle size pigment having a particle size of greater than 0.6 microns and wherein the substantially non-absorbing scattering pigment is a large particle size titanium dioxide pigment having a particle size greater than 0.6 microns; (ii) obtaining a reflectance spectrum, using a spectrometer, at least over wavelengths in the visible spectrum and infrared spectrum of the mixture of the scattering coloured pigment with a substantially non-absorbing scattering pigment at a plurality of different volume fractions; and (iii) obtaining a scattering coefficient of the substantially non-absorbing scattering pigment as a function of volume fraction and wavelength and storing the scattering coefficient in a color model calculator.