| 摘要 |
<p>PURPOSE:To obtain a humidity sensing ink which can form a thick printed layer causing a distinct color change in response to a change in humidity by mixing a water-soluble substance suitable as binder and cobalt chloride with a very fine powder having good hygroscopicity, and adding water thereto for conditioning. CONSTITUTION:A water-soluble substance suitable as binder, such as carboxymethylcellulose or PVA, and cobalt chloride are mixed with a very fine powder having good hygroscopicity (one obtained from flocks, wool yarn, refuse, paper, etc.), and water is added to this mixture for conditioning, thus giving the title ink. Because of the incorporation of the very fine powder having good hygroscopcity, this ink can give a thick printed layer. Since the powder serves to accelerate moisture absorption to thereby accelerate the change in color of cobalt chloride, the layer printed with this ink causes a distinct color change.</p> |
