摘要 |
<p>Described herein is an epoxy composition comprising: a first component comprising an amine-based curing agent and a first dye, having a first color; and a second component comprising a curable epoxy resin and a second dye, having a second color. Also described herein is a shelf-life-indicating composition comprising: an amine-based curing agent; and a dye selected from (i) a cationic triarylmethane dye, wherein the cationic triarylmethane dye reversibly reacts with a primary amine; (ii) a halochromic dye having a color transition range between 7-12 when measured in an aqueous solution; or (iii) combinations thereof.</p> |