Effective and sustainable solutions for the denim industryBack
1 Denim industry leads towards sustainability
The denim industry is leading the fashion business towards sustainability, and the protagonists of this change are many and profoundly influence each other in a virtuous circle.
- Institutions frequently update the policies to protect the health & the environment;
- manufacturers progressively manifest and act their commitment to a more sustainable industry;
- designers & brands start to design collection with a more sustainability-conscious mindset from the beginning, instead of applying it only at the production stage;
- consumers are more aware of their purchases' impact and shop accordingly with their values
- the most relevant certification bodies constantly restrict their criteria.
In the end, circular economy and fashion sustainability are the actual topics for the next future of the textile business: every fashion brand moves towards more responsible business models. The whole supply chain needs to step up the game to meet the needs.
As part of the denim supply chain, our products integrate and work in denim production, especially the slasher dyeing process.
We have a vast portfolio that covers pretreatment (prewetting, scouring, and mercerization), dyeing (dispersing, sequestering agents, and fixing agents), dyestuff (Sulfotex range), sizing (lubricants and antistats) finishing, and denim washing.
2 Pretreatment process
Pretreatment consists of prewetting, scouring, and mercerization of the yarn: a quick and uniform prewetting of the thread is needed (provided by our Natron 350, ZDHC certified, GOTS approved, and GRS compliant), together with low foaming and emulsifying action (provided by SULTAFON 70, our detergent for alkaline scouring, bluesign®approved, ZDHCc certified, listed by Inditex, GOTS approved, and GRS compliant).
During this phase, it's essential to prevent heavy metals like iron, calcium, magnesium present in cotton from precipitation by keeping the additives evenly dispersed in the bath.
(with SEQUION 48/98, bluesign®approved, ZDHC certified, listed by Inditex, GOTS approved, and GRS compliant).
3 The dyeing phase
The dyeing phase requires an optimized quantity of chemical auxiliaries for an excellent performance of the process.
As indigo and sulfur are insoluble pigments without affinity for cellulose in the oxidized state, the dyestuffs need to be reduced in a soluble form, usually with caustic soda and a potent reducing agent. Therefore dispersing, wetting, and leveling agents are essential to the dyeing process.
Dyeing processes vary based on the different shades of color needed: indigo bottoming, indigo topping, colored and black denim can be carried out through our Sulfotex range of sulfur dyes.
The sulfur dyestuff performance and evenness can be improved by adding auxiliaries such as Reducing agents:
- REDUCTOR SVP POLVO: bluesign®approved, ZDHC certified, screened chemistry by Scivera;
Wetting-emulsifying agent to improve dye penetration:
- PRODER FSE 184 M: ZDHC certified and GOTS approved;
- FIMBIL E-AS: low foaming, bluesign®approved, ZDHC certified, listed by Inditex, GOTS approved and GRS compliant;
Sequestering and dispersing agents to improve the migration and leveling of disperse dye during ht dyeing:
- ASUTOL LB: bluesign®approved, ZDHC certified, GOTS approved, screened chemistry by Scivera;
- SOLOPOL ZB CONC, sugar polymer derivate, bluesign®approved, ZDHC certified, listed by Inditex, GOTS approved and GRS compliant;
Leveling agent to slow down the dye uptake of the yarns helping to produce more uniform color in the textile fiber:
- PERMULSIN ELF EXTRA:bluesign®approved, ZDHC certified, listed by Inditex, GOTS approved and GRS compliant;
And product for oxidation of sulfur dyestuffs:
- OXIDANTE BRI: ZDHC certified, screened chemistry by Scivera).
At the end of the dyeing process, when the threads are washed and rinsed, it's crucial to fix the color and remove the exceeding dyestuff to improve the rubbing fastness:
- FISSAT BFD fixing agent specific for slasher and rope dyeing, ZDHC certified, listed by Inditex and GRS compliant;
ASUFIX MF-E, specially indicated for dark shades, ZDHC certified, and GOTS approved
4 Sizing: protecting the thread
The sizing phase is fundamental to protect the yarn from breakage during the stressful weaving process.
The sizing agents must be entirely removed after weaving to prevent any problem during the finishing process.
As starch-based agents are not soluble in water, they require an enzymatic desizing process, while synthetic polymer-based agents are water-soluble and can be easily removed with water and washing agents:
- WISAL DNM S is a revolutionary synthetic sizing compound with more than 50% lower pick-up and high efficiency on the last generation weaving machine.
MEGALASE G24 are enzymes to desize denim fabric GOTS approved and GRS compliant;
5 Finishing by padding
The final step of denim fabric treatment is finishing by padding: with this process, the fabric assumes the needed features, such as a soft hand feel and sewability or easy-care anti-crease effect:
- ALFALINA B 100 cationic softener with antistatic properties, ZDHC certified, listed by Inditex, GOTS approved, and GRS compliant;
- CEROFIL FTD, bluesign®approved, ZDHC certified, listed by Inditex, GOTS approved, and GRS compliant;
- SEBOSAN PRK elastomeric finishing for extra elasticity, bluesign®approved, ZDHC certified, listed by Inditex, and GRS compliant;
REACEL ZF, anti-crease resin bluesign®approved, ZDHC certified, listed by Inditex, and GRS compliant;
6 The fashion kingdom
It's now time for manufacturing and denim washing: we enter the fashion kingdom.
To meet the super-demanding needs of the fashion business, we have an entire line dedicated to denim washing and garment dyeing: the marvelous Asutex Garment Lab.
Check out our remarkable latest developments and all the opportunities you have to develop a sustainable clothing collection!