Warp Dyeing Padders
|No.||Warp Dyeing Padders Features||Specs|
|1||Dyes||Indigo and Sulphur|
|2||Processing Speed/Dwell Time||0.2-5m/min|
|3||Process speed indication display resolution||0.05-0.1m/min|
|4||Nip Pressure||Up to 6 bar|
|5||Temperature Control Accuracy||_1_0.5-1.5 °C|
Traditional dyeing processes always need heat to fix colour into the fabric. With Cold Pad Batch (CPB) techniques, the dyeing liquor and fabrics are rolled at room temperature, therefore saving energy significantly. CPB was introduced for reactive dyes in 1957 with very simple technology: padding. Read more about List of Dyeing Machine for Fabric dye in Textile
Most new driers come with built-in control equipment. Therefore this measure is especially attractive in case existing drying equipment is replaced. The cost of instruments for measuring the remaining moisture in dried fabrics ranges from USD 6 000 to 12 000. Savings are achieved through the reduced energy consumption (up to 30%), less risk of excess drying (10 to 15% productivity increase) and an improvement of the quality of the final product. Besides, in case the sales price of the fabric is based on the weight, a higher moisture level will raise the sales value of the product (2 to 3% increase).
Cold pad batch dyeing is a widespread technology for the semi-continuous dyeing of cellulose (mainly cotton and viscose) woven and knit fabric with reactive dyestuffs. The dyeing liquor and necessary auxiliary chemicals, like alkali for fixation, are fed to a dyeing trough for pad batch dyeing for impregnating the textile. The reactive dye, together with necessary alkali (Na2CO3 or NaSiO3) for fixation, is padded to cellulose fibres (cotton, viscose, lyocell, linen…) from a padder for impregnating. The impregnating fabric is maintained for 6-24 hours at room temperature (25-30oC) for meeting wet colourfastness. Then the fabric is rinsed out to clean the dyestuff on its surface.
This is one of the simplest methods and applied widely in Europe. This method is recommended due to :
• Low energy consumption
• Low investment in equipment and labour
• Good quality in colour, its fastness and reproducibility
• Reduction of pollution load
As the liquor ratio is 1:6, there is a significant reduction in the amount of water and chemicals. Besides, this method does not require salts, as in other exhaust or pad-steam dyeing methods. It is estimated that 80% of BOD, COD can be reduced.
CPB dyeing is a widespread technology for the semi-continuous dyeing of cellulose (mainly cotton or viscose) woven and knit fabric with reactive dyes.
Padders: Investment costs is EUR 250 000.