Laboratory to Bulk Correlation in Knit Dyeing and Finishing : Guideline for lab-dip and bulk knit fabrics dyeing

The activities of wet processing industries, especially in the dyeing department starts from the preparation of Lab-dip sample as per the given swatch or standard color code (i.e. Pantone color code either TC or PC, buyer's standard color code etc.) from the buyer or customer. Then the recipe is being prepared by spectrophotometer or manually and sent for the approval. After the approval of lab-dip, the recipe is sent to the dyeing floor for the bulk production. The difficulties found during the bulk dyeing process are that, the recipe of the dyeing lab does not give the same shade in the bulk dyeing. This creates lots of problem in the dyeing section. It is a very challenging job for a dyer to match the shade of the bulk production to the Lab-dip. But due to this problem; lab to bulk reproducibility is being hampered. This is the main reason of dyeing reprocessing and refers several times for re-dyeing and stripping. Both of which are not economical practice for a dye house. In order to know the lab to bulk correlation of knit dyeing and finishing, several experiments have been carried out to find out the correlation of lab-dip and bulk dyeing and finishing.