Freshness indicator for foodstuffs and medicines - comprises colour change indicator or crystals which melt when temp. rises

摘要

Indication of freshness of frozen materials, e.g. food, medicines, etc. uses a colour change indicator or crystals which melt when the product is subjected to an undesirable increase in temp.. The indicator is enclosed within the package which does not need to be unsealed. The crystals are used as an indicator for blind, colour blind or partially sighted people.