Titanium salts (potassium titanium oxalate and tanno-titanium oxalate) may be employed in conjunction with the coal-tar colours for dyeing chrome leather, with many advantages over the ordinary mordants, the colour produced being faster to light, rubbing, fuller in shade, and with much less tendency to “grinning.” When employing titanium mordants, the leather should be first lightly mordanted with some tannin solution and afterwards dyed with the titanium and dye-stuff in the same bath, in which case only “acid” dyestuffs may be employed. If desired the goods may be mordanted with the tannin mordant, afterwards treated with the titanium salts, washed and dyed; in this case the dyeing and application of the titanium mordant being carried out separately, the leather may be dyed with either the acid or basic dye stuffs. The titanium and tannin mordants may also be applied in the same bath.
Dyeing Chamois Leather.
The following colours dye chamois leather well, after washing the leather in a weak soda solution, mordanting with 3 per cent. basic chrome alum solution, and transferring to the dye-bath without washing. Equal weight of bisulphate of soda to that of the dyestuff is added to the dye-bath.
Basic Coal-Tar Colours.
- Bismark brown extra. (Ber.)
- Philadelphia yellow R. (Ber.)
- Pure phosphine. (C.)
- Leather blue V. (G.)
- Leather brown Y. (S.C. Ind.)
- Leather brown A. (S.C. Ind.)
- Philadelphia brown. (Ber.)
Acid Coal-tar Colours.
- Circumine extra. (Ber.)
- Resorcin brown. (Ber.)
- Induline NN. (B.A.S.F.)
- Orange 2. (M.L.B.)
- Golden brown. (Leitch.)
- Fast brown. (By.)
- Azo-yellow R. (M.L.B.)
- Napthylamine black 4B. (C.)
- Chocolate. (Uer.)
- Azo-flavine RS. (C.)
- Azo-phosphine. (Uer.)
- Acid anthracene brown R. (By.)
- Acid green conc. (M.L.B.)
- Acid brown Y. (S.C. Ind.)
- Acid brown B. (S.C. Ind.)
- Napthylamine black 4B. (O.)
- Jet black cryst. (C.)
- Anthracene brown R. (By.)
- Anthracene brown GG. (By.)
- Anthracene brown W. (By.)
- Dark nut brown. (Uer.)
- Orange 2. (M.L.B.)
Natural Dyestuffs.
- Peachwood extract.
- Sapan ext.
- Logwood ext.
- Fustic ext.
- Turmeric ext.
A variety of shades may be obtained on chamois leather by mordanting in a 1 per cent. solution of the titanium salts above mentioned and then transferring without washing to the dye-liquor, which is best used in the drum. The colours which are most suitable are the Alizarin colours, Janus colours and the natural dyestuffs.