Thermochromic Compositions From Trisubstituted Pyridine Leuco Dyes

A thermochromic leuco dye composition comprising:

• a leuco dye moiety including one or more tri-aryl substituted pyridines, the leuco dye moiety constituting from about 1 weight percent to about 50 weight percent of the composition, and
• a UVA developer moiety including at least one UVA developer selected from the group consisting of salicylic acid and derivatives thereof, and biphenyls and derivatives thereof,
• the UVA developer moiety constituting from about 2 weight percent to about 50 weight percent of the composition;
• and
• a carrier selected from the group consisting of a fatty ester, fatty alcohol, fatty amide, and combinations thereof,
• wherein the fatty ester, fatty alcohol and fatty amide reach have a carbon number ranging from 10 to 28,
• the carrier being present in an amount ranging from about 50 weight percent to about 97 weight percent of the composition.