MERTSIZE CMS
A size that washes out — no enzyme, no holding period.
Carboxymethyl starch dissolves in water. That single property removes the enzyme step from desizing, and the waiting that goes with it.
Desizing needs no amylase — and therefore no enzyme dosing, storage, activity window or deactivation step.
The size dissolves and washes away, instead of having to be broken down chemically before it will leave the yarn.
A modified natural polymer from a renewable raw material, readily biodegradable in the effluent.
The problem with native and modified starch
Starch and its derivatives account for the large majority of sizing agents used worldwide, because they are cheap and available. The difficulty comes afterwards. Neither native nor conventionally modified starch dissolves in water, so neither can simply be washed off. The size has to be broken down chemically before it will leave the yarn.
In practice that means α-amylase enzyme plus a wetting agent, applied in a saturator bath, then a holding stage at elevated temperature — in whatever equipment the line uses for it — while the enzyme hydrolyses the starch into water-soluble fragments, and only then a wash to carry those fragments away. That holding stage commonly runs from fifteen minutes to two hours, and in some regimes considerably longer.
Everything downstream depends on it. If desizing is incomplete, scouring, bleaching and dyeing all inherit the problem — patchy absorbency, poor whiteness, uneven shade.
How CMS changes the step
MERTSIZE CMS is carboxymethyl starch: starch that has been etherified so that carboxymethyl groups sit on the polymer chain. Those groups make it an anionic, water-soluble polymer. It still forms the film the warp needs during weaving — but because it is soluble, it comes off in water rather than needing to be digested first.
Native / modified starch desizing
- Prepare enzyme bath — amylase, wetting agent, correct pH and temperature window
- Saturate the fabric
- Hold at elevated temperature while the enzyme works
- Deactivate the enzyme
- Hot wash to remove the fragments
- Check TEGEWA rating, re-treat if incomplete
CMS desizing
- Enzyme bath — not required
- Hot wash
- Holding stage — not required
- Enzyme deactivation — not required
- Check TEGEWA rating
What that saves
| Area | Effect |
|---|---|
| Water | Fewer wash stages are needed to reach a clean TEGEWA rating, because there are no enzyme residues and no partially hydrolysed starch to chase. |
| Time | Nothing has to wait on an enzymatic reaction to complete, so fabric moves from desizing to scouring sooner. |
| Chemicals | No amylase, no enzyme stabiliser, no separate deactivation step. Fewer products to buy, dose and store. |
| Labour | No enzyme bath to prepare and monitor. pH and temperature windows for enzyme activity no longer constrain the line. |
| Energy | A shorter process with fewer heated stages, and no need to hold a bath within an enzyme temperature window. |
| Effluent | A biodegradable, readily removed size means a lower load reaching wastewater treatment. |
The size of each saving depends on your current desizing regime, machinery and water. We quantify it during the trial rather than quoting a single figure.
What the literature reports
Published work on carboxymethyl starch as a warp size found that cotton yarns sized with CMS gained around 39% in tensile strength against unsized samples, with desizing efficiency close to 98% achieved at 30 °C. Carboxymethyl derivatives are described consistently as dissolving in cold and hot water, which is precisely the property that removes the enzyme step.
These are literature values for the chemistry in general, not measurements of MERTSIZE CMS. Ask us for the technical data sheet for figures on our own grade.
Where it fits
- Cotton, linen and blended spun yarns; small to medium counts
- Mills wanting to shorten pre-treatment without changing machinery
- Processes where enzyme handling, dosing windows or effluent load are a constraint
- Programmes with sustainability targets, where a biodegradable size is required
Carboxymethyl starch beyond textiles
The same chemistry is used well outside the mill. As an anionic, cold-water-soluble polymer, carboxymethyl starch thickens, binds and retains water — which makes it useful anywhere a process needs controlled viscosity or reduced filtration.
- Drilling fluids — fluid-loss control in water-based muds, drill-in and workover fluids. It builds a tough, low-permeability filter cake, limits formation damage and helps hold the wellbore stable, including in salt formations.
- Paper — surface sizing and coating.
- Ceramics — binder and suspending agent, including electrode manufacture.
- Adhesives and construction chemicals — binder in adhesives, water-retention agent in putty, tile adhesive and plaster mortar.
- Printing — thickener for print pastes.
What we can supply today. The same name does not mean the same product: each of these applications calls for its own degree of substitution, viscosity and purity. Our current production is formulated for textile sizing, and we know the formulations for drilling grades but have not yet produced them commercially. If you need carboxymethyl starch for another industry, send us the specification you have to meet — we will tell you plainly whether we can make it, and when.
The product
MERTSIZE CMS is manufactured by MertChem. It is supplied in 25 kg bags, with technical and safety data sheets issued for every delivery. Our products are OEKO-TEX certified and registered to ZDHC Level 3.
Trialling CMS. Send your yarn count and construction, current size recipe and add-on, and your desizing regime. We will propose a starting recipe, send a lab sample free of charge, and work through the first run with you.
See the full MERTSIZE sizing range →
Frequently asked
What is carboxymethyl starch (CMS)?
Carboxymethyl starch is starch that has been etherified so that carboxymethyl groups sit on the polymer chain. This makes it an anionic polymer that dissolves in cold and hot water, unlike native starch.
Why does CMS not need an enzyme to desize?
Native and modified starches are insoluble, so they must be broken down by amylase before they will leave the yarn. CMS is water-soluble, so it washes out — the enzyme bath, its holding stage and the deactivation step are not needed.
Is carboxymethyl starch used in drilling fluids?
Yes. In water-based drilling muds CMS is used for fluid-loss control: it forms a tough, low-permeability filter cake, limits formation damage and helps keep the wellbore stable, including in salt formations.
Can MertChem supply CMS for industries other than textiles?
Our current production is formulated for textile sizing. Grades for drilling, paper, ceramics or adhesives need a different degree of substitution, viscosity and purity. Send us the specification you must meet and we will tell you whether and when we can produce it.
How is MERTSIZE CMS packed?
In 25 kg bags, with a technical data sheet and safety data sheet issued for every delivery. Our products are OEKO-TEX certified and registered to ZDHC Level 3.