CALICO-PRINTING 663 



France, and the recipe for it will be found below. James Higgin patented subse- 

 quently the employment of salts of oxide of chromium, such as tungstate, arseniate, 

 &c., mixed with an insoluble copper salt, such as arseniate or tungstate, hydrochlorato 

 of aniline and chlorate of potash being used along with them. In this colour the 

 chrome oxide acts as a carrier of oxygen, chromic acid being formed and instantly 

 decomposed again by the aniline, some chloride of copper being also formed by the 

 mutual reaction of the hydrochlorate of aniline, and the arseniate of copper further 

 assists in the reaction. This black has been and is largely used. There is still some 

 action of this colour upon the ' doctor,' and there is a liability of tendering the cloth 

 when printed in heavy masses. To prevent any action upon the steel ' doctors,' Higgin 

 patented the use of the disulphocyanide of copper, a substitute for the sulphide of 

 copper of Lauth, it having been found that under some conditions of printing the 

 sulphide of copper was decomposed and a soluble copper salt formed in the furnishing- 

 box of the printing machine, and even sometimes in the colour before being put in the 

 furnishing-box. The disulphocyanide of copper is perfectly insoluble in hydrochloric 

 acid, and, of course, equally so in the hydrochlorate of aniline ; there is no soluble 

 copper salt formed until the colour is printed and dried. This colour has bof n and 

 is still very extensively used. The most recent improvement is that patented by 

 Lightfoot in 1871. Chlorate of soda or ammonia is used instead of chlorate of potash 

 and a much larger proportion of aniline is used than in former colours, this being not 

 quite neutralised by hydrochloric acid, making, as the patentee says, a basic salt of 

 aniline ; the chlorates of soda and ammonia being much more soluble than the potash 

 salt, allows a larger quantity to be used. Sulphide of copper is the copper salt used 

 in this black. The patentee claims that no injurious action on the ' doctor ' takes 

 place in printing this colour, and that patterns of any size and body can be printed 

 without tendering the fibre, also that the intensity of the black is so great owing to 

 the large quantity of aniline used, that it resists the action of a sulphureous atmo- 

 sphere like that of manufacturing towns longer than other blacks. Lightfoot proved 

 by several experiments that the only metals which develope aniline black from a 

 mixture of hydrochlorate of aniline and chlorate of potash are vanadium, copper, 

 uranium, and iron. Their activity is in the order in which they are here placed. 

 The black from iron salts is not nearly so good as that from copper, and practically a 

 good black can only be made where a copper salt is employed. The exact reactions 

 set up in the aniline-black colour have not been yet satisfactorily explained. M. 

 Brandt, in a paper recently read before the Societe Industrielle of Mulhouse, asserts 

 that there are two distinct blacks, one of them of a brownish shade and the other of a 

 blue shade, and that a black of the best and most solid appearance is a mixture of the 

 two blacks. 



No. 241. C. Kachlin's Black. 20 Ibs. of starch, 201bs. dark British gum, 2 gallons 

 of aniline, 2 gallons of water, beat up well together, and add the following solution : 

 8 gallons of water, 11 Ibs. chlorate of potash, 11 Ibs. of sal-ammoniac ; boil all well 

 for 1 hour and cool, then add 1 gallon of sulphide-of-copper paste. When about to 

 print, add to every gallon of the above colour 22 oz. of tartaric acid, dissolved in 



1 pint of hot water, it must be added gradually, and well stirred in. This is a very 

 disagreeable colour to make, and a quantity of the aniline is boiled off. The sulphide 

 of copper is made as follows : 



A. 2 quarts of caustic soda solution at 70 T., 1 Ib. of flour of sulphur, dissolve 

 by constant stirring ; 



B. 9 gallons of water, 5.J Ibs. sulphate of copper, heat to 170 F. 



Add A to B, stirring well, let settle and wash by decantation 4 times, filter to 



2 quarts of paste. 



No. 242. Higgin's Disulphocyanide-of-Copper Black. 1 gallon of water, 1 Ib. wheat 

 starch, 1 Ib. dark British gum, 2 oz. of disulphocyanide paste, boil, and add 8 oz. 

 chlorate of potash, cool, and add 1 Ib. of hydrochlorate of aniline. 



No. 243. Lightfoot's Chlorate-of-Soda Black. 1 gallon of chlorate paste, No. 244 

 48 oz. measure basic hydrochlorate-of-aniline solution, No. 246,1 pint sulphide of copper 



No. 244. Chlorate Paste. 10 gallons of water, 23 Ibs. wheat starch, 5 Ibs. sal- 

 ammoniac 4 Ibs. chlorate of potash, 2 gallons chlorate-of-soda solution, No. 245, boil 

 and cool. 



No. 245. Chlorate-of-Soda Solution. 1 gallon of caustic soda solution at 70 T., 13 

 quarts of water in which has been dissolved 7 Ibs. tartaric acid, heat up to 170 F., 

 and add 12 Ibs. chlorate of potash, dissolve, and add a solution of 7,} Ibs. tartaric 

 acid in 6J quarts of water, stir till cold, filter and press the sedinjent with a weighted 

 board, then take it off and mix with 1 gallon of cold water, and filter and press 

 again. Mix the filtrates, and set at 28 T. 



No. 246. Basic Hydrochlorate of Aniline. 8 measures of aniline and 6 of muriatic 

 acid at 34 T. 



Aniline black unless basic should not be hard dried after printing, but only just enough 



