Cold dye
Also known as: Cold dyeing
Energy-saving dyeing process with highly reactive dyes at 20-30 degrees instead of 60-80.
Description
Cold dye is a dyeing process where cotton is dyed with highly reactive dyes such as the Procion MX series at ambient temperatures of 20-30 degrees. The extreme reactivity of these dichlorotriazine dyes allows the dyeing bath to run cold instead of at 60-80 degrees while still achieving high yields and wash fastness. The dye-cellulose reaction is activated with sodium carbonate (soda) and long dwell time (cold pad batch, 6-24 hours).
The process is particularly established in Cold Pad Batch (CPB): fabric is padded cold with dye and alkali solution, wound onto a batch and slowly rotated. Over hours the covalent bond of dye to cellulose forms without additional heat. After dwell the fabric is rinsed and dried.
Advantages: 30-50 percent less energy than conventional reactive dyeing, less water, compact process. Cold dye is widespread in cotton weaving mills and marketed by brands like H&M and Zara as a sustainability feature. Limits: only medium and dark shades economically, very pale shades need complex after-treatment.
Properties
| Process | Cold pad batch with Procion MX dyes |
|---|---|
| Result | Full colour depth, 30-50 % energy saving |
| Colour fastness | High (covalent reactive bond) |
Related product categories
Sources & references
2- Wikipedia: Reactive dye Wikipedia — Freie Enzyklopädie https://en.wikipedia.org/wiki/Reactive_dye
- DyStar Cold Pad Batch dystar.com https://www.dystar.com/
