Water-based dual security ink
AssigneeNCR Corporation
InventorsYaoping Tan, Maurice W. Lewis
Life of this patent
Estimating the term…
Abstract
A water-based security printing ink is provided with two means of security. The use of a variable light absorbing and/or transmitting pigment or dye is a first security and a water repelling agent is provided as a second security. Visible images can be generated from the printed ink upon exposure to UV or infrared light. The water repelling agent renders the image waterproof and differentiates the printed image from the substrate, which allows the image to be detected upon exposure to water or other aqueous mixture. Suitable inks can be used in conventional printing methods, such as jet printing, lithography, offset printing and impact printing. Also provided are substrates imaged with these security printing inks.
Claims16
A water-based security printing ink which is water proof once dried, and which comprises:
- (a) a water soluble, dispersible or emulsifiable pigment or dye
- (b) a carrier for said pigment or dye selected from the group consisting of aqueous solutions and water soluble, dispersible or emulsifiable binders;
- and
- (c) a water repelling agent dispersed in the carrier (b) in an amount sufficient to render the ink water proof once dried, wherein the water soluble, dispersible or emulsifiable pigment or dye is selected from thermochromic, photochromic and fluorescent pigments and dyes.
A jet printing ink which is waterproof when dry, comprising an aqueous solution as a carrier and a water soluble, emuslsifiable, or dispersible dye or pigment selected from fluorescent, photochromic and thermochronic pigment and dyes in an amount of 2 to 50 wt. % based on dry components and a water repelling material selected from the group consisting of varnishes, vinyl emulsions, arcrylic resins and silicone resins, in an amount of 1-10 wt. % based on dry components.
Dependencies are inferred from the claim text.