Thermochromic ink formulations and methods of use

A kit for creating a document with a pattern camouflage comprising said following:

• a) a color changing ink that is permanently reversible between colorless and colored in response to temperature or light;
• b) a non color changing ink that is color matched to said non color changing ink such that when said color changing ink has a color it is close enough in color to said non color changing ink that it is difficult for a human observer to detect a color differential between said inks on said a printed with said inks.

A method of camouflaging a pattern on a document comprising the steps of:

• a) selecting a color changing ink that is permanently reversible between colorless and colored in response to temperature or light;
• b) selecting a non color changing ink that is color matched to said non color changing ink such that when said color changing ink has a color it is close enough in color to said non color changing ink that it is difficult for a human observer to detect a color differential between said inks on said a printed with said inks;
• c) printing a document using said color matched color changing ink and said non color changing ink such that a pattern is camouflaged when said color changing ink is colored and a pattern is revealed when said color changing ink turns colorless.

A solvent based ink formulation comprising:

• a) a thermochromic pigment, wherein said thermochromic pigment is formed of microcapsules each containing reversible thermochromic coloring material which exhibits a visible change in color between a first color state and a second color state in response to a change in temperature;
• and
• b) an appropriate mixing base that has an inherent or adjusted acid value that is not harmful to said thermochromic pigment and does not include any solvents that are harmful to said thermochromic pigment.

A method of lithographic printing comprising the step of using distilled water as a fountain solution.