Thermochromic ink formulations, nail lacquer and methods of use

A method of making a solvent based ink formulation including 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, comprising:

• a) drying a slurry including thermochromic pigment to a solids concentration between 80% and 95%;
• b) mixing said dried slurry in an appropriate mixing base that has an inherent or adjusted acid value lower than 100 and does not include anymore than trace amounts of the following solvents:
• ketones, diols, aldehydes, amines and aromatic compounds thereby making a base formulation, wherein said mixing base is selected from one or more of the following:
• 1) mixing varnish, 2) polyester resin vehicle;
• and 3) colloidal dispersion resin;
• and
• c) adding any desired ink components to said base formulation wherein said ink components have an inherent or adjusted acid value that is below 100 and do not include any more than trace amounts of the following solvents:
• ketones, diols, aldehydes, amines and aromatic compounds.