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Home • About Us • Laboratory Services • Forensic Science Communications • Back Issues • July 2005 • Research • Figure 1: Structures of Dyes and Additives...

Figure 1: Structures of Dyes and Additives Important to Differentiate Among Ink Formulations

Figure 1: Structures of Dyes and Additives Important to Differentiate Among Ink Formulations

Figure 1 shows the structures of the dyes and additives in the ink formulations identified in pens A-J.

a) Hexamethylpararosaniline (i.e., Crystal Violet)
b) Pentamethylpararosaniline (i.e., Methyl Violet)
c) Victoria Blue backbone; Victoria Blue B- R=R''=CH3, R'=C6H5; Victoria Blue R- R=R''=CH3, R'=CH2CH3; Victoria Pure Blue BO- R=R'=R''=CH2CH3
d) 1,3-di-o-tolylguanidine
e) Disulfonated Copper Phthalocyanine