Sulfur Brown 4,5,14,53,62. Sulfur Brown 14 is obtained by heating o- or p-(2,4-dinitroanilino)phenol with caustic soda and water to 105⁰C and then add dextrose, sodium sulfide and sulfur. Sulfurization temperature may vary from 123⁰C (under reflux) to 160⁰C (bake).
Dyes from substituted naphthalenes:
Brown dyes of this type include C.I. Sulfur Brown 7,15,16,31,63. Sulfur Brown 15 is obtained by Obtained by baking a mixture of 138 parts of 1,5-dinitronaphthalene and 75 parts of crude cresol with sodium polysulfide, in the presence of copper sulfate and sodium chloride at 265⁰C for 12-14 hours. The 1,5-dinitronaphthelene may be reduced at 95⁰C with sodium polysulfide before baking.
Dyes from polycyclic compounds: Brown dyes of this type include C.I. Sulfur Brown 6,51,52,60. Sulfur Brown 52 is obtained by by baking a mixture of decacyclene and sulfur at temperatures up to 350⁰C during 20 hours and maintaining at this temperature for a further 8 hours. The product is treated in caustic soda at 100-110⁰C, filtered and precipitated. This dye possesses exceptionally good fastness to