Reasons for Influencing Shrinkage Rate of Textile Fabrics
1. Raw materials
The shrinkage of fabrics varies with the raw materials. Generally speaking, the fibers with high hygroscopicity will swell, increase in diameter, shorten in length, and increase in shrinkage. If some viscose fibers absorb water up to 13%, while synthetic fabrics have poor hygroscopicity, their shrinkage is small.
The shrinkage rate varies with the density of the fabric. If the density of longitude and latitude is similar, the shrinkage ratio of longitude and latitude is also close. If the warp density is high, the warp shrinkage will be large. On the contrary, if the weft density is greater than the warp density, the weft shrinkage will be large.
3. Yarn count
The shrinkage rate varies with the yarn count. The shrinkage of yarn count thick cloth is larger, and that of fine yarn fabric is smaller.
4. Production Technology
Fabric shrinkage varies with different production processes. Generally speaking, in the process of knitting and dyeing and finishing, the fibers need to be stretched several times, the processing time is long, the shrinkage rate of the fabric with greater tension is large, and vice versa is small.
5. Fiber Composition
Compared with synthetic fibers such as polyester and acrylic fibers, natural plant fibers (such as cotton, hemp) and regenerated plant fibers (such as viscose) have higher moisture absorption and shrinkage, while wool is simply felt because of the scale structure of the surface of the fibers, which affects its scale stability.
6. Fabric structure
In general, the dimensional stability of woven fabrics is better than that of knitted fabrics, and that of high density fabrics is better than that of low density fabrics. In general, the shrinkage of plain weave fabric is less than that of flannel fabric, while in knitted fabric, the shrinkage of plain knitted fabric is less than that of rib fabric.
7. Production and Processing Processes
In the process of dyeing, printing and finishing, the fabric will inevitably be stretched by the machine, so tension exists on the fabric. However, the fabric is very easy to release tension when it meets water, so we will find that the fabric shrinks after washing. In practice, we usually use pre-shrinkage to solve this problem.
8. Washing nursing process
Washing care includes washing, drying and ironing. Each of these three steps will affect the shrinkage of the fabric. For example, the scale stability of hand-washed samples is better than that of machine-washed samples, and the temperature of washing also affects the scale stability. Generally speaking, the higher the temperature, the worse the stability. The drying method of samples also has a great influence on the shrinkage of fabrics.
The commonly used drying methods are dripping drying, metal mesh laying, hanging drying and rotary drying. The drip drying method has the least influence on the fabric size, while the rotary cylinder arch drying method has the greatest influence on the fabric size, the other two are in the middle.
In addition, choosing an appropriate ironing temperature according to the composition of the fabric can also improve the shrinkage of the fabric. For example, cotton and linen fabrics can be ironed at high temperatures to improve their scale shrinkage. But not the higher the temperature, the better. For synthetic fibers, high temperature ironing can not improve its shrinkage, but will damage its performance, such as hard and brittle fabrics.
Article from Guangdong textile fabric manufacturerHttp://www.dongqunfangzhi.com