Naik, Shailaja DMagadi, Renuka B2019-08-142019-08-142002No. of references 64http://krishikosh.egranth.ac.in/handle/1/5810121549"The present investigation entitled ""Studies on the effect of scouring, bleaching, mercerization and cleansing agents on the physical properties of naturally coloured cotton and white cotton yams"" was carried out during 2001-02 at Dharwad. Three colour cotton genotypes namely Hirsutum Cream Cotton-1 (HCC-1), Hirsutum Colour Cotton-7 (HCC-7), Dharwad Brown Hirsutum-12 (DBH-12) and one white cotton Jayadhar were selected for the present study. The experiment carried out at yarn stage included treating the yams with scouring agents viz., soda ash (Si), a mild alkali and caustic soda (S2), a strong alkali. The Si and S2 scoured genotypes were separately bleached with two bleaching agents viz., hydrogen peroxide (Bi) and sodium hypochlorite (B2) and mercerized with strong caustic soda. The survey was conducted to collect information regarding various cleansing agents used for domestic laundering. Based on the survey results four cleansing agents viz.. Wheel cake, Rin Supreme cake. Wheel powder and Surf Excel detergent powders were selected. The Si and S2 scoured genotypes were washed upto ten washes. After scouring, bleaching, mercerization and fifth and tenth washings the genotypes were assessed for single yam strength and change in pigmentation using computer colour matching system under daylight, tungsten, tubelight-83 and tubelight-84 illuminations. There was increase in the single yarn strength among all the genot3'pes on scouring, but the colour genotypes showed better improvement when scoured with caustic soda. Scouring led to yellowing of white cotton. Remarkable increase in yarn strength was achieved on mercerization over control. Washing did not adversely affect the durability of the genotypes but infact enhanced the strength upto fifth wash. Hypochlorite bleaching did enhance the single yarn strength of all the genotypes where as hydrogen peroxide reduced the same. Scouring, mercerization and washings enhanced the pigmentation of colour genotypes. Bleaching drastically faded the pigment of colour cotton while Jayadhar regained the brightness on bleaching."ennullThesis