What do You need to Know about Moisture Wicking and Quick Dry Fabric Clothing?

Moisture wicking & quick dry fabrics are fabrics that allow clothes to dry faster, compared to woollen or cotton clothes, which are more likely to evaporate water and dry faster under the same external conditions.

Moisture wicking & quick dry fabrics do not absorb sweat, but transfer it quickly to the surface of the clothes and evaporate it through air circulation, thus achieving the purpose of quick dry. Generally quick dry fabrics dry 50% faster than cotton fabrics.

1 What kind of fabric is moisture wicking and quick dry?

The hydrophilic and hydrophobic properties of the inner and outer layers of the moisture wicking and quick dry fabric are different, with the outer layer of the fabric being hydrophilic and the inner layer mostly hydrophobic. Sweat is transferred from the small hydrophilic part of the inner layer to the hydrophilic outer layer of the fabric and evaporates quickly in the outer layer. At the same time, due to the hydrophobic nature of the inner fibres, the surface tension of the inner layer of the fabric is higher and perspiration does not remain in the inner layer, thus helping to keep the skin dry.

When the body sweats, the hydrophobic inner layer does not stain the body. In addition, the outer layer of the fabric evaporates quickly to remove a large amount of heat, thus making the body feel cooler. Moisture wicking and quick drying is an automatic response process, therefore, moisture wicking and quick dry fabric is a technological smart fabric.

Moisture wicking and quick dry fabrics are generally made of a composite double-layer construction. The inner fabric structure conducts moisture or perspiration quickly from the body surface to the outer fabric, keeping the skin in contact with the fabric dry and comfortable. The outer fabric structure evaporates the released moisture or perspiration as quickly as possible, while ensuring that the released moisture or perspiration does not re-enter the inner layer of the fabric, achieving a single wicking effect.

For example, the moisture wicking, quick dry T-shirt has an outer layer with a concave and convex grid type textile structure, which increases the surface area for diffusion evaporation from the outer layer by more than 30%, which equates to an enhanced evaporation efficiency from the outer layer, further achieving the effect of quickly dispersing sweat into the air. In a practical test, a few drops of water were placed on the inner fabric and it was dry in 4 minutes.

When water is dripped onto the surface of the garment, it spreads quickly and the inner layer remains dry against the skin.

When water is dripped onto the inner layer of the garment, it spreads quickly to the outer layer and the inner layer remains dry.

2 How to achieve moisture wicking and quick drying of fabrics

Two conditions required for moisture wicking and quick drying.

• A good capillary effect in the inner layer of the fabric.
• A good diffusion of moisture by the outer layer of the fabric.

The key to moisture absorption and quick drying is the gradient wettability of the inner and outer layers of the fabric, resulting in a differential capillary effect. In practice, this can be achieved by a variety of processing methods, mainly including chemical, plasma modification and structural design methods.

Chemical method

The chemical method mainly uses chemical finishing agents to finish the surface of the fabric, thus changing the moisture absorption properties of the fabric. Depending on the finishing agent used and the finishing surface, it can be divided into single-sided hydrophobic finishing, single-sided hydrophilic finishing and pro-hydrophobic finishing on both sides.

One-sided hydrophobic finishing

Single-sided hydrophobic finishing is to use hydrophobic agents on one side of the fabric, so that the finishing side has hydrophobic, while the other side remains hydrophilic, forming a differential capillary effect on both sides of the fabric, thus achieving moisture wicking and quick drying.

Single-sided hydrophilic finishing

Single-sided hydrophilic finishing is the use of hydrophilic finishing agents on one side of the fabric hydrophilic finishing, so that the fabric on both sides of the formation of moisture absorption difference, in the role of differential capillary effect, to achieve moisture wicking and quick drying.

Hydrophilic and hydrophobic finishing

Two-sided finishing is a hydrophilic finish on one side of the fabric and a hydrophobic finish on the other. A significant differential capillary effect is created between the inner and outer layers of the fabric, resulting in moisture wicking and quick drying.

With two-sided finishing, the differential capillary effect is stronger than with single-sided finishing and the effect of moisture conduction is better. However, if the fabric is lighter and thinner when finishing on both sides, the hydrophilic and hydrophobic finishing agents will easily come into contact at the critical position, thus destroying the single-sided moisture-conducting effect.

Plasma modification method

Plasma modification is a chemical treatment followed by plasma irradiation of the fabric to give the fabric moisture wicking and quick drying properties. The plasma modification method is simple, efficient and can be combined with other technologies. For example, heating the plasma-treated fabric and then re-irradiating it with plasma will change the direction of the fabric’s moisture wicking and is expected to be widely used in the field of intelligent textiles.

It should be noted that the plasma modification method is significantly time-sensitive, with a shorter duration of the moisture wicking and quick drying effect of the fabric, probably due to the weaker bonding of the silane to the plasma.

Structural design

By designing the fabric structure and configuring the fibre raw materials, the fabric can also effectively moisture wicking and quick drying. The structural design method does not use chemical reagents and the fabric can come into direct contact with the human body, which is beneficial to the environment.

The disadvantage of this method is that the fabric surface density is often too high, and the use of nanotechnology is limited by the output, and the structural design method is limited by the output, the structural design method is often applied to knitted fabrics, the structural design of woven and non-woven fabrics is still relatively small.

For example, a special three-dimensional structure of the mesh can facilitate and accelerate the transfer of moisture and heat from the inner layer to the outer layer. The larger the mesh of the inner layer and the smaller the mesh of the outer layer, the faster the conduction of perspiration from the inside to the outside and the faster it evaporates and dries in the outer layer.

3 What are the common moisture wicking and quick dry fabrics? What are their characteristics?

Polyester

Polyester is commonly known as “terylene” and is widely used in everyday life. The composition of quick dry fabrics is often based on polyester. Its advantage is that it has good wrinkle resistance and shape retention, and is second only to nylon in terms of abrasion resistance. The disadvantage is that it has poor wicking properties and can cause discomfort when water is absorbed. In addition, polyester fabrics are prone to static electricity, which affects wearing comfort.

Polyamide

Polyamide, also known as ‘nylon’, has the highest abrasion resistance of any fabric and is extremely durable. Nylon fabric has good moisture absorption, elasticity and elastic recovery and is a lighter fabric, making it more comfortable to wear than polyester. The disadvantage is that nylon fabrics are easily deformed under small external forces and nylon fabrics are easily wrinkled during wear. In addition, nylon fabrics are less resistant to light and heat, so care must be taken during wear to avoid damage to the garment.

Polypropylene

Polypropylene fibre has many advantages, such as: light, high strength, good elasticity, wear-resistant and corrosion-resistant, easy to wash, absorb odours, but also anti-static, sunlight, insect resistance, anti-mould, anti-staining and other excellent performance. The disadvantage is that polypropylene dyeing performance is poor, the colouring is lighter. However, on balance, polypropylene is still an excellent choice of fabric for quick-drying garments.

Due to some difficulties in the production process that have not yet been overcome, it is not common to see polypropylene fibres used in quick-drying garment fabrics. At present, polyester and nylon are still the two most commonly used components of quick-drying garment fabrics on the market.

4 How do I assess and test the moisture wicking and quick dry properties of fabric?

In 2010, the American Associa-tion of Textile Chemists and Colorists (AATCC) approved a test method for testing the moisture wicking and quick dry properties of sportswear and other garments, primarily using a unidirectional transfer index (MMT) to indicate a fabric’s ability to transfer perspiration excreted by the body in one direction.

Currently, the dynamic transfer characteristics of liquid moisture in textiles are tested using the AATCC 195, GB/T 21655.2 test standard, which tests for the following.

• Absorption speed – The time taken for moisture to be absorbed on the front and back of the fabric.
• Accumulative one-way transport capacity – the differential absorption and diffusion of the liquid on both surfaces.
• Rate of diffusion/drying – the rate of diffusion of the liquid on both sides of the fabric.

Test equipment: Moisture Management Tester

• Metal construction housing with good immunity to external interference signals.
• Test sensor with built-in pressure detection device, automatic stop when moving to a fixed pressure and automatic return when the test is over
• Uniform and stable pumping water, no blocking of pipelines.
• Instant connection to PC, more stable and reliable data transmission.

Conforms to standards AATCC 195, GB/T 21655.2

The test should be carried out with the inside of the fabric (i.e. in contact with the skin) positioned upwards. The specific AATCC 195 indicators and grading criteria are shown in the table below.

Index		level
		1	2	3	4	5
Wetting time / S	Outer fabric	≥120	20~119	5~19	3~5	<3
	Fabric lining	≥120	20~119	5~19	3~5	<3
Absorption speed / (%/S)	Outer fabric	0~9	10~29	30~49	50~100	>100
	Fabric lining	0~9	10~29	30~49	50~100	>100
Maximum wetting radius / MM	Outer fabric	0~7	8~12	13~17	18~22	>22
	Fabric lining	0~7	8~12	13~17	18~22	>22
Spreading speed / (MM/S)	Outer fabric	0.0~0.9	1.0~1.9	2.0~2.9	3.0~4.0	>4.0
	Fabric lining	0.0~0.9	1.0~1.9	2.0~2.9	3.0~4.0	>4.0
Accmulative one-way transport capacity / R		<-50	50~99	100~199	200~400	>400
Overall moisture management capability (OMCC)		0.00~.0.19	0.20~.0.39	0.40~.0.59	0.60~0.80	>0.80

If you would like to know more specific testing methods of the moisture management tester, you can consult the expert technicians of TESTEX.

5 What should I know about washing moisture wicking and quick dry fabrics?

• Machine wash in cold water with regular washing powder (strong detergent is not recommended) and use the normal spin cycle.
• Do not dry clean and do not dry in the machine.
• Do not use hot water or soak.
• Do not use bleach or fabric softener.
• For best results, turn the clothes inside out and wash them separately.
• It is normal for quick drying materials to show a little pilling due to their fine fibre structure.
• For products with iron-on or iron-on stamps, reverse and wash separately.
• The mosquito and UV protection range will fade after approximately 20 washes.

Research into moisture-wicking and quick-drying fabrics involves a number of disciplines, such as chemistry, physics, materials and engineering. Although there is already a certain basis for such research, many aspects are still problematic and need further refinement and refinement.