prov:value
| - Donald R. Titterington, and Clifford R. King, the disclosure of which is totally incorporated herein by reference, discloses colorant compounds of the formula wherein R, R1, R 2, R3, and R4 each, independently of the others, is an alkyl group, an aryl group, an arylalkyl group, or an alkylaryl group, and wherein R, R1, R2, R3, and R4 each can be joined to a phenyl moiety to form a ring, each R???a
|