| 摘要 |
Water soluble marking compounds comprising a transition metal oxyanion and at least one ammonium cation, comprising a nitrogen atom at least one further group selected from the group consisting of OH, COOH, NH2, NHC1-5 alkyl, and N(C1-5 alkyl)2, wherein the two C1-5 alkyl may be the same type of alkyl or different alkyls, may be used to obtain clear imageable coatings. |
