STIMULUS INDICATING DEVICE EMPLOYING POLYMER GELS

摘要

The present invention relates to an apparatus for evidencing when a stimulus sensitive product has been exposed to a designated or predetermined stimulus for a certain period of time, and the invention further may include a method for manufacturing aspects of that apparatus.

主权项

1. A stimulus indicating device that permanently indicates exposure to a predetermined stimulus comprising:
a first compartment; said first compartment connected to a second compartment by a neck portion; a window portion contained in said first portion; and a stimulus sensitive gel contained in and contiguous through said first compartment, said neck portion and said second compartment; wherein said neck portion is configured to prevent said stimulus sensitive gel from reentering said first compartment after said stimulus sensitive gel retracts out of said first compartment due to a change in volume arising from said stimulus sensitive gel being exposed to a predetermined stimulus.