Sulphur dyes are complex heterocyclic molecules or mixtures formed by melting or boiling organic compounds containing amino or nitro groups with sodium polysulfide and sulfur. Sulphur dyes are so named because they all contain Sulphur bonds in their molecules. Sulfur dyes are named for the Sulphur atoms in their molecules. Like direct dyes, sulfur dyes are very inexpensive when dyeing cellulosic fabrics with limited fastness.

Sulphur dyes are strongly colored water-insoluble compounds that must be converted into water-soluble immediate forms (lucoforms) before they can be applied to textile materials. The transformation is carried out by treatment with a reducing agent such as dilute aqueous Na2S. This lucoform due to sulfur dyes is direct to cellulosic materials.

Refined naphthalene is a naphthalene of the chemical formula C10H8. It is an aromatic crystalline compound. It is a simple hydrocarbon used with many other chemicals to make dyes and synthetic resins. Refined naphthalene is used to make dyes, fuels and plastics. It is obtained by high-temperature cracking of heavy petroleum molecules.

The most common use of naphthalene is as mothballs in pesticides and insecticides. The downstream applications of refined naphthalene are mainly intermediates of dyes and organic dyes. At the same time, it is used as the main raw material of mothballs.