Patent ID: 7517475

Claim:
A method for producing a thermal indicator material which comprises: providing a plurality of compounds having the following structure: wherein R 1 -R 6 =a hydrogen, substituted or unsubstituted alkyl radical, substituted or unsubstituted alkoxy radical, substituted or unsubstituted aryl radical, substituted or unsubstituted thioalkyl radical, substituted or unsubstituted trialkylsilyl radical, substituted or unsubstituted acyl radical, substituted or unsubstituted ester radical, substituted or unsubstituted amine radical, substituted or unsubstituted amide radical, substituted or unsubstituted heteroaryl or substituted or unsubstituted aryl radical n is between 1 and 1000, m is between 0 and 1000, and l is between 1 and 1000; the compounds exhibiting a first low temperature color and structured to exhibit a high temperature color when the compound is exposed to temperatures above a pre-determined temperature; heating the compounds to a temperature of within a range of between about 130° C. and 160° C. to form heated compounds; cooling the compounds to a temperature within a range of between about 0° C. and 30° C. for a time period of less than 2.0 seconds to form cooled compounds, the cooled compounds exhibiting a second low temperature color and exhibiting a color change from the second low temperature color to the high temperature color when the thermal indicator material is exposed to a temperature that meets or exceeds the pre-determined temperature and exhibiting a color change from the high temperature color to the first low temperature color when the thermal indicator material is exposed to a decline in temperature from a temperature that meets or exceeds the pre-determined temperature to a temperature within the range of between about 5 to 20° C. below the pre-determined temperature, the decline in temperature occurring in a time period of greater than 2.0 seconds.