A PRECISE CRITICAL TEMPERATURE INDICATOR AND MANUFACTURING METHOD THEREOF

摘要

A precise critical temperature indicator and a control method thereof comprising as one body, a blocking boundary layer which is positioned between a spreading material member including an operation button and spreading medium members including a spreadable area for a spreading material; and a temperature sensor which is controlled and operated as the spreading material passes through the blocking boundary layer and contacts the spreading medium member according when pressing of the operation button. The precise critical temperature indicator does not require a process of cooling a product down to below a critical temperature before using the product, due to the hermetic sealing of the spreading material member. Mass production can be realized by combining a spreading material member sheet including a plurality of spreading material members and a spreading medium member sheet including the spreading medium members which includes a plurality of spreadable areas for the spreading material.