ORANGE II. C. I. NO. 151 



Synonyms: Gold orange. Orange A, P, or R. Acid orange. 

 Orange extra. Mandarin G. Tropaeolin 000 No. 2. 



N = N 



NaS03 \/\/ 



(^An acid dye; absorption maximum about Jlt.90) 



This dye, which differs from Orange I only in the position of the 

 hydroxyl group on the naphthalene radical, is similar to it in color 

 and properties, but does not change color with changing reaction 

 of its solution. 



NARCEIN C. I. NO. 1 52 



{An acid dye) 



This dye is a derivative of Orange II, prepared from the latter 

 by treatment with sodium bisulfite. It is rarely used either as a 

 textile dye or in microscopic technic. It has been called for by 

 Ehrlich, however, in combination with pyronin and methyl green 

 or methylene blue to form a neutral dye. 



AMARANTH C. I. NO. 1 84 



Synonyms: Naphthol red. Fast red. Bordeaux. Bordeaux SF. 

 Victoria rubin. Azo rubin. Wool red. 



N = N 

 /HO \ 



NaS03 SOiNa 



NaSOj 



{An acid dye; absorption maximum about 525) 



Amaranth is not a commonly used stain, but is of considerable 

 importance as a food color. It has been used by Griesbach for 

 staining axis cylinders. 



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