What Is Desizing in Textiles?
Desizing is the first wet-processing step in textile finishing where warp sizing agents applied during weaving are removed from the fabric.
Sizing is essential for weaving strength, but must be removed before dyeing, printing, or finishing because residual size:
Blocks dye penetration
Causes uneven shades
Increases chemical consumption
Traditionally, desizing relies on enzymes (amylase) or oxidative/acid treatments to break down starch-based or synthetic sizing films.
To learn more about the Desizing Process, click here.
Why Is Desizing Necessary?
Desizing is necessary because most conventional sizing agents are not naturally water-soluble once dried on yarn.
Without desizing:
Dyes cannot access fiber surfaces
Printing paste penetration is restricted
Finishing chemicals perform inconsistently
Fabric defects like patchiness and streaks appear
In short, desizing exists to correct the chemical complexity introduced during sizing.
What Happens If Desizing Is Not Done Correctly?
Incorrect or incomplete desizing leads to downstream quality failures:
Patchy or uneven dyeing
Poor colorfastness
Increased reprocessing
Higher effluent load
Reduced finishing efficiency
Ironically, many finishing problems originate not in finishing-but in the sizing chemistry used at the loom stage.
Are Enzymes Needed in Desizing? Can We Reduce or Stop Using Them?
Short answer: Enzymes are only needed because of traditional sizing chemistry.
Why enzymes are used:
To hydrolyze insoluble starch films
To break down complex polymeric sizing layers
To reduce fabric damage compared to acids
However, enzymes:
Add cost
Increase process time
Generate COD/BOD in effluent
Are sensitive to pH and temperature control
How enzyme use can be reduced or eliminated
By switching to water-soluble sizing agents that:
Dissolve directly in hot water
Do not require molecular breakdown
Leave no resistant film on fibers
This is where Sizaltex-type sizing technology becomes relevant-not as a product pitch, but as a process redesign.
What Is the Role of Sizing Agents in Desizing?
Desizing difficulty is directly proportional to sizing agent complexity.
Type of sizing agent | Desizing requirement |
Conventional starch | Enzymatic |
PVA / synthetics | Hot alkali + surfactants |
Modified starch blends | Enzyme + wash |
Water-soluble polysaccharides (Sizaltex type) | Hot water only |
In other words:
Desizing problems are created during sizing, not finishing.
What Effluents Are Released During Desizing and How Do They Harm the Environment?
Traditional desizing releases:
Hydrolyzed starch fragments
Synthetic polymers (PVA residues)
Enzyme degradation by-products
Surfactants and wetting agents
Environmental impact
High COD & BOD
Increased load on ETPs
Sludge generation
Poor biodegradability (especially PVA)
This makes desizing one of the most environmentally expensive “invisible” processes in wet processing.
How Can Desizing Effluents Be Reduced?
Desizing effluent reduction can be achieved by:
Lower size add-on
Better size uniformity
Eliminating synthetic polymers
Reducing enzymatic hydrolysis
But the largest reduction comes from eliminating the desizing chemistry itself.
How Can Desizing Be Avoided in Textiles?
Desizing can be functionally avoided by changing sizing philosophy
Instead of asking “How do we remove size?”, progressive mills ask:
“Why are we applying something that needs removal at all?”
Water-Soluble Sizing Approach
Modern water-soluble sizing systems (such as Sizaltex):
Form a strong yet fully water-dispersible film
Maintain weaving efficiency
Do not crosslink irreversibly on yarn
Dissolve completely in hot water
Practical Outcome
Fabric desizing = simple hot wash
No enzymes
No acids
No alkali
No desizing auxiliaries
At a process level, this collapses desizing into a basic washing step.
How Sizaltex Changes the Desizing Equation (Process Perspective)
Characteristics of Sizaltex:
Polysaccharide-based
Fully water-soluble
Stable sizing film during weaving
Completely desizes via hot water
From a mill operations standpoint, this means:
Desizing step becomes optional
Enzyme procurement eliminated
Shorter wet-processing cycles
Lower effluent treatment cost
Better dye reproducibility
This aligns sizing, desizing, and sustainability into one continuous system, instead of three disconnected problems.
How to Reduce Overall Desizing Costs
Cost reduction does not come from cheaper enzymes - it comes from not needing them.
Key cost-reduction levers
Eliminate enzyme usage
Reduce water consumption
Cut heating cycles
Lower ETP load
Reduce reprocessing and shade corrections
Water-soluble sizing like Sizaltex directly impacts all five levers simultaneously.
What Are Sustainable Practices in Desizing?
True sustainability in desizing means designing it out of the process.
Sustainable desizing principles
Use biodegradable sizing agents
Avoid synthetic polymers
Prefer thermal solubility over chemical breakdown
Minimize auxiliary chemicals
Reduce effluent complexity
Water-soluble sizing technologies are increasingly aligned with:
ZDHC goals
GOTS processing requirements
Low-impact wet processing
Cleaner production benchmarks
Key Insight: Desizing Is a Symptom, Not a Requirement
Desizing exists because traditional sizing chemistry creates insoluble residues.
When sizing chemistry evolves:
Desizing simplifies
Enzymes become redundant
Effluent load collapses
Sustainability improves organically
This is not a finishing innovation-it is a weaving-stage decision with finishing-stage consequences.
Frequently Asked Questions
Can desizing be completely eliminated?
Functionally yes, when water-soluble sizing systems like Sizaltex are used.
Is enzyme desizing mandatory for cotton fabrics?
Only if conventional Starch or PVA sizing is used.
What temperature is required to remove water-soluble sizing?
This depends from chemical to chemical. Sizaltex typically desizes with 80–90 °C hot water.
Does enzyme-free desizing affect dye quality?
No, shade consistency often improves due to uniform size removal.
Is this approach suitable for high-speed looms?
Yes, provided the sizing film has adequate abrasion resistance during weaving. Companies like Arvind, PeeVee and Baldev LLP are regular purchasers of Sizaltex.
References
ZDHC Wastewater Guidelines (Desizing Effluent Reduction Strategies),
https://downloads.roadmaptozero.com/output/ZDHC-Wastewater-Guidelines
ZDHC Wastewater V1.1 (Enzyme-Free Wet Processing),
https://wastewater.sustainabilityconsortium.org/downloads/zdhc-wastewater-guidelines-verson-1-1/
Textile Wastewater Standards (Sizing Removal Effluent),
ZDHC Wastewater PDF (Sustainable Desizing Alternatives),
https://lederpiel.com/wp-content/uploads/2019/08/ZDHC_WastewaterGuidelines_V1.1_JUL19.pdf
Wastewater Technologies for Desizing (ETP Load Minimization),
https://studylib.net/doc/28191281/wastewater-treatment-technologies-for-the-textile-industr...
GOTS Implementation Manual (Low-Impact Desizing),
https://global-standard.org/images/Implementation_Manual_7.0_Second_Revision_Draft.pdf
GOTS Official Site (Organic Sizing Removal),
OEKO-TEX Standards (Chemical-Free Finishing Prep),
https://www.oeko-tex.com/en/our-standards/
OEKO-TEX STeP (Process Optimization),
https://www.oeko-tex.com/en/our-standards/oeko-tex-step/
ZDHC-OEKO-TEX Collaboration (Effluent from Sizing/Desizing),
https://www.oeko-tex.com/en/news/infocenter/zdhc-and-oeko-tex-strengthen-collaboration
PMC: Potato Starch Sizing (Hot-Wash Desizing Only),
https://pmc.ncbi.nlm.nih.gov/articles/PMC6572457/
PMC: Starch Graft Copolymer (Enzyme Reduction),
https://pmc.ncbi.nlm.nih.gov/articles/PMC10820382/
PMC: Corn Starch Derivatives (Water-Soluble Films),
https://pmc.ncbi.nlm.nih.gov/articles/PMC7361798/
PMC: Sustainable Starch Systems (No-Residue Removal),
https://pmc.ncbi.nlm.nih.gov/articles/PMC11137591/
ACS ES&T: PVA-Free Biodegradable Sizing (Desizing Avoidance),
https://pubs.acs.org/doi/10.1021/es504988w
PubMed: Slashing with Easy-Desize Alternatives,
https://pubmed.ncbi.nlm.nih.gov/25687520/
ScienceDirect: Pollution Reduction via Sizing Design,
https://www.sciencedirect.com/science/article/abs/pii/S0959652613006598
Inflibnet: Desizing Methods (Enzymatic vs Hot Wash PDF),
_ ...
ICIRESM: Wet Processing Impacts (Desizing Effluents),
...
Wiley: Textile Effluent Treatment Review (Sizing Residues),
https://onlinelibrary.wiley.com/doi/abs/10.1002/tqem.21538
ScienceDirect: Wet Processing Assessment (Desizing Sustainability),
https://www.sciencedirect.com/science/article/abs/pii/S0048969722065949
GarmentsMerchandising: Desizing in Fabric Prep (Avoidance Strategies),
https://garmentsmerchandising.com/difference-between-greige-fabric-and-rfd-fabric/
TextileSchool: Sizing Removal Techniques (Water-Soluble),
https://www.textileschool.com/206/basic-weaving-operations/
TextileLearner: Warp Desizing Processes,
https://textilelearner.net/different-parts-of-loom-and-their-functions/
Persistence: Sizing Market (Innovative Desizing-Free Systems),
https://www.persistencemarketresearch.com/market-research/textile-sizing-chemicals-market.asp
MarketsandMarkets: Chemicals for Wet Processing (Enzyme Reduction),
https://www.marketsandmarkets.com/Market-Reports/textile-chemical-market-12380328.html
Mordor Intelligence: Market Analysis (Sustainable Sizing),
https://www.mordorintelligence.com/industry-reports/textile-chemicals-market
Heuritech: 2026 Trends (Process Simplification),
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Disclaimer
The information provided in this blog is intended solely for educational and informational purposes within the textile industry. While the content references technical concepts, sizing and desizing practices, and general chemical information, it does not constitute professional, commercial, or operational advice for any specific textile process or production environment.
Process conditions, chemical selections, and operational parameters may vary significantly across mills, machinery types, fabric constructions, and environmental constraints. Readers should always consult qualified technical professionals, internal laboratory data, and product-specific Technical Data Sheets before making any decisions related to textile processing.
Any references to Alpenol, Sizaltex, or other products are included only for contextual, educational, and illustrative purposes and should not be interpreted as endorsements, recommendations, or guarantees of performance. The authors assume no responsibility for decisions made based on the information contained herein.
