| abstract |
An N-(monosubstituted)dithiooxamide compound of the formula:n wherein R 3 comprises:n (a) an alkyl or aralkyl group having 11 or more carbon atoms; or (b) a group of the structure -R 4 -Y-R 5 wherein: (i) when Y is a functional group selected from the group consisting of -N(R 6 )C(O)-, -C(O)N-(R 6 )-, -N(R G )-, -N(R G )C(0)0-, -OC(O)N(R 6 )-, and -N(R 6 )C(O)N(R 7 ), wherein R 6 and R 7 are independently hydrogen, or an alkyl or aralkyl group having 1 to 12 carbon atoms: R 4 is a divalent alkyl or divalent aralkyl group having 1 to 12 carbon atoms; R 5 is hydrogen, or an alkyl or aralkyl group having 1 to 20 carbon atoms; and, the total number of carbon atoms in R 4 plus R 5 is at least 7; or (ii) when Y is a functional group selected from the group consisting of -OC(O)-, -C(O)O-, and -OC(O)O-: R 4 is a divalent alkyl or divalent aralkyl group having 1 to 12 carbon atoms; R 5 is hydrogen, or an alkyl or aralkyl group having 1 to 20 carbon atoms; and, the total number of carbon atoms in R 4 plus R 5 is at least 9. n Preferred materials are those for which when the monosubstituent dithiooxamide is complexed with a transition metal cation, the resulting polymer is substantially a dark, i.e., blue or blue-black color. Carbonless paper constructions involving use of N-(monosubstituted)dithiooxamides to advantage are described. |