Crease marks are one of the most common and troublesome quality problems in fabric dyeing, especially when processing knitted, elastic, lightweight or soft-structured fabrics.
During dyeing, hydro extraction, opening and finishing, fabric may be folded, compressed or subjected to uneven tension. If fabric circulation, loading condition, nozzle pressure, liquor flow or post-dyeing handling is not properly controlled, visible crease marks may remain on fabric surface.
Creasing is not only an appearance problem. When fabric remains folded during dye uptake, folded and open areas may experience different liquor contact and dyeing conditions, which can result in local shade variation or uneven dyeing. For this reason, crease prevention should be considered throughout the whole process rather than only after dyeing is completed.
Crease marks are visible lines, bands or irregular marks formed when fabric is locally folded, compressed, rubbed or unevenly tensioned during wet processing.
Typical symptoms include:
A crease mark is therefore not simply caused by fabric being folded once. If fabric stays folded under pressure while temperature, circulation and dye absorption continue, dyeing conditions at the folded area can become different from those on the rest of fabric.
Knitted fabrics generally have a softer and more flexible structure than many woven fabrics. They can stretch, curl, twist and accumulate more easily during loading and circulation.
Creasing risk is often higher for fabrics such as:
These materials normally require more careful control of fabric tension, nozzle force, circulation speed and accumulation inside the dyeing machine.
Some fabrics naturally have lower resistance to folding and compression. Soft knitted fabric, high-stretch fabric and lightweight fabric can easily curl, twist or pile during processing. Even a relatively small deviation in operating conditions may therefore lead to visible creasing.
Fabric condition before entering the dyeing machine is important. Rolled edges, knots, twisting, uneven tension or folded fabric can already create an unstable running condition.
If the fabric enters the machine in this condition and continues circulating without being corrected, local folds may remain for a long period and gradually develop into crease marks.
Fabric speed should match fabric weight, elasticity, machine loading, nozzle flow and storage chamber condition. Running speed that is too high or too low may disturb stable fabric circulation.
Creasing should not be attributed to low liquor ratio alone. Modern dyeing machines increasingly operate at lower liquor ratios. The key issue is whether fabric loading, liquor circulation, nozzle flow, machine geometry and fabric movement are properly matched.
If fabric accumulates excessively or cannot move freely, compression and repeated folding may increase.
Unstable nozzle pressure, worn guide components, poor transmission, rough internal surfaces or fabric accumulation inside the machine may create uneven pulling or squeezing forces.
A dyeing process that previously operated normally can suddenly start producing crease problems if guide wheels, nozzles, pumps or fabric transport components are not properly maintained.
When fabric remains folded during high-temperature dyeing, the folded area is continuously compressed while dye liquor circulation and dye absorption continue.
This can cause both mechanical crease marks and local shade differences. If abnormal fabric accumulation or folding is observed during production, it should be corrected as early as possible rather than waiting until the end of the dyeing cycle.
Incomplete scouring, residual oil, poor wetting or unsuitable pretreatment chemicals may cause uneven liquor absorption.
When these problems occur together with fabric folding, dye uptake can become less uniform, making crease-related shade differences more visible.
Not every crease mark is created inside the dyeing machine. Hydro extraction, opening, fabric piling, transportation and waiting before finishing can also create secondary creases.
If wet fabric remains compressed or folded for an extended period after dyeing, these marks may become more difficult to remove during subsequent finishing.
Crease formation is influenced by fabric, process and operation, but dyeing machine design also plays an important role in maintaining stable fabric movement.
For delicate and elastic knitted fabrics, excessive pulling force may stretch the fabric and increase instability during circulation. Dyeing machines designed with a lower fabric lifting height can help reduce unnecessary longitudinal tension.
Fabric should circulate continuously and smoothly through nozzle, guide system and storage chamber. Repeated stopping, excessive piling, sudden acceleration or uneven fabric transport can increase the risk of folding and compression.
Higher nozzle pressure is not always better. Lightweight, elastic and delicate fabrics may require gentler liquor flow. Nozzle setting should be adjusted according to fabric structure, GSM, elasticity and required cloth speed.
The storage chamber should allow fabric to accumulate naturally without excessive compression. Poor fabric piling can cause repeated folding in similar areas and may lead to recurring crease marks.
Variable fabric speed, pump flow and nozzle settings allow operators to adapt machine conditions to different fabrics instead of using one fixed operating condition for every batch.
When crease marks appear, it is better to identify the pattern first rather than simply treating the problem as poor dyeing.
| Observed Problem | Possible Cause | What to Check First |
|---|---|---|
| Crease repeatedly appears at similar position | Guide system, nozzle, fabric path or mechanical condition | Guide wheel, nozzle, fabric transport and internal contact points |
| Creases appear randomly | Fabric twisting, accumulation or unstable circulation | Loading condition, fabric speed and storage chamber |
| Crease accompanied by obvious shade difference | Fabric remained folded during dye absorption | Liquor circulation, fabric movement and dyeing stage |
| Fabric looks normal in machine but creases appear later | Post-dyeing handling | Hydro extraction, opening, piling and transportation |
| Elastic fabric shows severe folding | Excessive tension or unsuitable nozzle condition | Fabric speed, nozzle pressure and lifting condition |
Crease prevention normally requires control at several stages:
The most effective solution is usually not one single parameter adjustment. Fabric structure, loading quantity, dyeing machine design and process conditions should be evaluated together.
Not necessarily. Low liquor ratio itself is not a direct cause of crease marks. Problems are more likely to occur when fabric loading, circulation flow, nozzle condition, fabric speed and machine geometry are not properly matched. A well-designed low-liquor-ratio dyeing machine can still maintain stable fabric movement when operating conditions are suitable for the fabric.
It depends on the type and severity of the crease. Light mechanical wrinkles may sometimes be improved during opening, relaxation or heat setting. However, if the folded area has already developed uneven dye absorption, severe compression or thermal fixation, the mark may not be completely removed during finishing.
For knitted, elastic, lightweight or crease-sensitive fabrics, machine selection should not be based only on nominal capacity.
Important factors include:
For applications where low fabric tension is particularly important, dyeing machines with a lower lifting height and controlled fabric transport can help reduce unnecessary mechanical stress. For general knitted fabric dyeing, suitable overflow or low-tension machine configurations should be selected according to actual fabric characteristics rather than using one machine type for every material.
Practical Note
Crease marks are rarely caused by one factor alone. When troubleshooting, evaluate fabric structure, loading condition, machine circulation, nozzle pressure, pretreatment and post-dyeing handling together. Repeated crease patterns often indicate a mechanical or fabric-path issue, while random marks are more commonly related to unstable fabric movement or handling.
Common causes include fabric folding, unstable circulation, excessive or uneven tension, unsuitable nozzle conditions, fabric accumulation, poor pretreatment and improper post-dyeing handling.
Knitted fabrics are generally softer, more elastic and easier to twist or accumulate during wet processing. This makes them more sensitive to fabric tension and circulation conditions.
Yes. Stable fabric circulation, lower unnecessary lifting tension, suitable nozzle control and proper fabric storage can reduce mechanical conditions that contribute to crease formation. However, process control and fabric characteristics remain equally important.
No. Crease marks may originate from fabric preparation, loading, dyeing conditions, machine condition, hydro extraction, opening or finishing. The location and pattern of the crease should be checked before determining the cause.
Crease marks in fabric dyeing are usually the result of several interacting factors rather than one isolated problem. Fabric structure, machine loading, circulation, nozzle pressure, fabric speed, pretreatment and post-dyeing handling can all affect final fabric appearance.
For crease-sensitive knitted fabrics, maintaining smooth circulation and low, controlled fabric tension is particularly important. When recurring crease problems occur, identifying where and when the crease is formed is the first step toward finding an effective solution.
