초록 ▼

There is provided a freeze indicator which includes a frangible ampule substantially filled with a mixture of water, a nucleating agent, and a surfactant. Upon reaching the freezing point of water, most of the water will freeze and expand, and fracture the frangible ampule. The nucleating agent has

There is provided a freeze indicator which includes a frangible ampule substantially filled with a mixture of water, a nucleating agent, and a surfactant. Upon reaching the freezing point of water, most of the water will freeze and expand, and fracture the frangible ampule. The nucleating agent has substantially similar molecular space grouping to frozen liquid to overcome the undercooling effect. The surfactant provides an increased surface area of contact between the water and the nucleating agent. The frangible ampule is in contact with a pad which has a water soluable dye printed on one side. When the ampule breaks, it releases some of the water, and the dye is wicked to one side of the pad by the water, showing a color change. In order to fine-tune the freeze indicator, varying amounts of deuterium oxide may be added to the water to raise its freezing point.

대표청구항 ▼

A freeze indicator comprising: a frangible container, said container housing a liquid which expands upon freezing, thereby fracturing said container, said liquid having a nucleating agent disbursed therein, said nucleating agent being substantially insoluble in said liquid, liquid responsive indicat

A freeze indicator comprising: a frangible container, said container housing a liquid which expands upon freezing, thereby fracturing said container, said liquid having a nucleating agent disbursed therein, said nucleating agent being substantially insoluble in said liquid, liquid responsive indicator means, said nucleating agent and said liquid having substantially similar molecular space groupings whereby undercooling of said liquid is substantially prevented; said container further housing a surfacant which is mixed with said liquid and said nucleating agent before freezing of said liquid for providing increased contact between said nucleating agent and said liquid and further providing a decrease in surface tension between said container, when fractured, and said liquid whereby a substantial immediate indication of freezing is provided on said liquid responsive indicating means.