Patent ID: 7829162
Filing Date: 2010-11-09
Classification: B41M,Y10T

Abstract:
1. A thermal transfer printing medium comprised of a thermal transfer layer, wherein: (a) said thermal transfer layer is comprised of a first colorant and a first taggant, wherein said first taggant comprises a fluorescent compound with a first excitation wavelength, and wherein said first excitation wavelength is selected from the group consisting of wavelengths of less than 400 nanometers, wavelengths of greater than 700 nanometers, and mixtures thereof; (b) said thermal transfer layer has a light transmittance of at least about 10 percent when illuminated by light having said first excitation wavelength of said first taggant; (c) when said thermal transfer layer is printed onto a white polyester substrate with a gloss of at least about 84, a surface smoothness Rz value of 1.2, and a reflective color represented by a chromaticity (a) of 1.91 and (b) of −6.79 and a lightness (L) of 95.63, when expressed by the CIE Lab color coordinate system, and when such printing utilizes a printing speed of 2.5 centimeters per second and a printing energy of 3.2 joules per square centimeter, a printed substrate is produced wherein: