Stages of heat-setting

If heat-setting is carried out in the loom state, mineral oils and non-ionic emulsifiers can modify the fibre stmcture and rubbing and perspiration fastness may be reduced due to the solubility of disperse dye in the coning oil [ 1 -4]. PV A size above 135 C looses its Tg which is followed by becoming crystallized and melts. The H-bonds, therefore, can no longer be broken with the result that PVA becomes difficult to remove from the fabric. However, grey heat-setting is useful in the 

Heat-setting can be carried out after scouring if it is suspected that the goods will shrink or for the cloth in which stretch or other properties are developed during a carefully controlled scouring process. However, this stage requires drying the cloth twice. 

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