
When the label is exposed to the selected temperature, the label turns from white to black.
Companies in this press-release
Telatemp (Fullerton, CA) has introduced Hot Spot recording labels for temperature-sensitive products. Available on rolls of 1ꯠ, these 0.2" dia labels can be made to detect a temperature from 100°F to 350°F in 10°F increments.
When the label is exposed to the selected temperature, the label turns from white to black.