Coloring agents, additives synthetic dyes

The process of textile print coloration can be divided into three steps. First, the colorant is appHed as pigment dispersion, dye dispersion, or dye solution from a vehicle caUed print paste or printing ink, containing in addition to the colorant such solutions or dispersions of chemicals as may be required by the colorant or textile substrate to improve and assist in dye solubUity, dispersion stabUity, pH, lubricity, hygroscopicity, rate of dye fixation to the substrate, and colorant-fiber bonding. The required viscosity characteristics of a print paste are achieved by addition of natural or synthetic thickening agents or by use of emulsions. 

These materials normally consist of pure film former plus solvent and additives, such as a drier and an antiskinning agent. Clear finishes may be oil and resin cooked into a varnish or a synthetic resin solution, such as an alkyd. Such finishes are normally transparent unless color is added in the form of a pigment or a dye, and they are glossy unless a flatting pigment is added. Properties depend on the oils and resins used and the conditions under which the varnish is processed. 

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