In the 1990s, Generra sportswear sold a brand of clothing under the
name Hypercolor.  The clothes made with a heat sensitive dye which
changed colors in reaction to body heat.  The two most common were a
blue/pink and green/yellow.  The dyes were made by Matsui Shikiso
Chemical of Japan.  The dyes may have been a micrencapsulated leuco
dye.  I'd like to know where in the United States I can buy small
quantites of these or similar heat sensitive color changing dyes for
personal use; I want to dye clothing with them.

Color Change Corporation in Addison, IL, makes these dyes. 
http://www.colorchange.com/

Give them a call and they may be able to help.