Indicator device using metal salts of polyacetylenic compounds
AssigneeAllied Corporation
InventorsAnthony F. Preziosi, Gordhanbhai N. Patel, Robert G. Denkewalter, Ray H. Baughman
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Abstract
Water-soluble polyacetylenic alkali metal salts from monomers and polymers of carboxymethyl urethanes of di-, tetra-, and hexayne diols, or from the corresponding diacids; useful in thermal and irradiation exposure indicators and/or in detection and/or removal of nonalkali metal ions dissolved in aqueous media.
Claims7
An activatable device for indicating exposure to the combined effects of time and temperature which comprises a compound deposited on a substrate, said compound being a monomer of the formula [R(C.tbd.C).sub.a (CH.sub.2).sub.b (C.tbd.C).sub.b-1 ].sub.2, a being 1 or 2 and b being 0 when a is 1 and b being 0, 1 or 2 when a is 2 and (b-1) being taken as zero whenever b is zero;
- wherein R is selected from the group consisting of (I):
- --(CH.sub.2).sub.n O(C.dbd.O)NHCH.sub.2 CO.sub.2 M, n being an integer from 1 to 10 and M representing an alkali metal;
- and (II):
- --(CH.sub.2).sub.n' CO.sub.2 M', n' being an integer from 0 to 9 and M' being an alkali metal;
- said compound being inactive as to undergoing color change at room temperature in daylight;
- and in which an aqueous source of acid is provided to allow activating said compound at a desired time by conversion thereof to the acid form with resulting polymerization and visible change in color or shade. .
Device for indicating exposure to the combined effects of time and temperature which comprises a compound deposited on a substrate, said compound being a monomer of the formula [R(C.tbd.C).sub.a (CH.sub.2).sub.b (C.tbd.C).sub.b-1 ].sub.2, a being 1 or 2 and b being 0 when a is 1 and b being 0, 1 or 2 when a is 2 and (b-1) being taken as zero whenever b is zero;
- wherein R is --(CH.sub.2).sub.n O(C.tbd.O)NHCH.sub.2 CO.sub.2 H, n being an integer from 1 to 10.
Dependencies are inferred from the claim text.