Role of Different Salts in Dyeing Process and their Replacement

Abstract

The present paper was aimed at studying possibility of using different organic salts as substitute of nondegradable inorganic salt in dyeing process as these inorganic electrolytes cause environment problems. Using cationic hydrolyzed starch derived from 2-hydroxypropyltrimethylammonium chloride resulted in enhanced rate of dye fixation with increased DS value for counteracting static repulsion between fibers and reactive dye. Exhaustion and fixation efficiency reported was 30g/L for reactive dyes when sodium edate was used as inorganic salt alternative while sodium citrate gave higher exhaustion and fixation efficiency of 25g/L for same dyes when compared. Use of PEO45 di-block copolymer derived from [2-(methacryloyloxy) ethyl]trimethylammonium chloride(MeDMA) has proved to provide strong attraction to anionic reactive dye increasing dye uptake to 5g/L which is optimum concentration for neutralizing fabrics. While polycarboxylic acid salts has shown same effects regarding exhaustion and fixation as that of sodium sulphate and sodium chloride evaluated by comparing K/S values.