EmploymeTit of Copper Mordant after Dyeing. 373 



When boiled with soap-suds (1 soap and 200 water) for a 

 quarter of an hour, the violet blue colour of the dye is 

 converted into a greenish blue. This withstands for a long 

 time soap-suds. 



Solution of potash makes green spots, which after being 

 treated with vinegar remain white. 



Lime water has no action. 



Ammonia, diluted with water, forms a purer blue. 



Lime juice produces orange-yellow spots, which vinegar 

 only so far removes as to make the places approach nearer 

 to a light blue. 



Tin mordant. No. 1, discharges a purple. 



Tin mordant. No. 2, acts in the same way, only the colour 

 is less clear. 



Solution of chloride of lime (1 to 40 water) has no action. 



EMPLOYMENT OF COPPER MORDANT AFTER DYEING. 



As the ammoniuret of copper combines with the mor- 

 danted calico, in the same way it combines with the dyed 

 cloth, and in this respect affords an unlimited field to the 

 dyer for varying his shades. No shade is produced which 

 is not altered by immersion in the copper mordant, No. 2. 



Copper mordants having alumina grounds, act quite 

 differently upon logwood colours. They change the log- 

 wood violet blue to a disagreeable colour ; while the blue 

 after some time acquires a gray hue. 



Compounds also of alumina, with substances containing 

 tan, as the brown from birch, alder, maple, oak and willow 

 barks, undergo various changes by the use of copper mordant. 



Madder-red imparts to the copper mordant a purple 

 colour, which is equal to that produced by the addition of 

 logwood ; being, however, much more permanent. 



Berry yellow is not much altered. It remains yellow 

 but loses all lustre. Quercitron yellow assumes a greenish 

 hue. 



Tan yellow produced with acetate of alumina mordant, 

 as well as yellow wood yellow becomes brownish yellow. 

 On the contrary, fernambuc red acquires a scarlet colour, 

 which is more durable than the pure red. 



To what has been already stated, it may be added, that 

 the colours cleared or shaded by ammoniuret of copper, 



