Patent ID: 6861012
Filing Date: 2005-03-01
Classification: B41M,C09D,G07F

Abstract:
1. A latent security marking formulation, comprising: a phosphor pigment having at least two distinct emission wavelength characteristics and particles cropped to particles of a resin binder, wherein at least one of said emission wavelength characteristics comprises fluorescent emission of light at a visible wavelength in response to excitation by irradiation of the pigment at an invisible wavelength, and wherein the phosphor pigment is provided with a particle size smaller than a predetermined maximum size for inkjet printing; and a volatile vehicle for carrying the pigment, wherein the formulation comprises 1% to 5% by weight of the pigment, wherein the pigment has distinct fluorescent responses at least at two excitation wavelengths, said distinct responses including different emission spectra responsive to said two excitation wavelengths.