Shrinkage is a phenomenon in which the length or width of textiles undergoes washing, dehydration, and drying in a certain state.
The fabric shrinks to a certain extent after being immersed in water, partly because the fibers in the fabric swell after absorbing water, the diameter of the yarn increases, and the degree of buckling in the fabric increases, forcing the fabric to shrink; another reason is in the process of weaving In order to keep the warp beam flat and make the opening clear, a certain tension is generally applied to the warp yarn. The weft yarn will also be subjected to a certain degree of mechanical external force during the process of being drawn, resulting in potential strain. Once the fabric is immersed in water, the yarn In a free state, the fabric will naturally shrink.
The factors affecting the degree of shrinkage involve fiber type, yarn structure, fabric structure, different external forces during fabric processing, etc. The specific effects of each factor are as follows:
1. Raw materials
Different fabrics have different shrinkage rates. Generally speaking, for fibers with high moisture absorption, after being immersed in water, the fibers expand, their diameter increases, their length decreases, and the shrinkage rate is large. If some viscose fiber has a water absorption rate as high as 13%, while the synthetic fiber fabric has poor hygroscopicity, its shrinkage rate is small.
2. Yarn thickness
Yarn is made up of fibers arranged by twisting and winding shafts. The size change in water is not only related to the nature of the fiber, but also related to its structure such as twist and tightness. Generally speaking, different fabric yarn counts have different shrinkage rates. The shrinkage rate of fabrics with thick yarn counts is large, and the shrinkage rate of fabrics with fine yarn counts is small.
3. Fabric density
The density of the fabric is different, and the shrinkage rate is also different. If the density in the warp and weft directions is similar, the shrinkage rate in the warp and weft directions is also close. Fabrics with a high warp density will shrink in the warp direction. Conversely, fabrics with a weft density greater than the warp density will shrink in the weft direction.
4. Fabric structure
In general, the dimensional stability of woven fabrics is better than that of knitted fabrics; in one weave cycle, the smaller the number of warp and weft yarns interlaced, the greater the shrinkage of the organization, and the worse the stability of the fabric.
5. Production process
Different fabric production processes have different shrinkage rates. Generally speaking, in the process of weaving, dyeing and finishing of the fabric, the fiber has to be stretched many times, and the processing time is long. The shrinkage rate of the fabric with greater applied tension is greater, and vice versa.
6. Washing care process
Washing care includes washing, drying, and ironing. Each of these three steps will affect the shrinkage of the fabric. For example, the dimensional stability of hand-washed samples is better than that of machine-washed samples, and the washing temperature will also affect its dimensional stability. Generally speaking, the higher the temperature, the worse the stability. The drying method of the sample has a relatively large impact on the shrinkage of the fabric.
Tips to reduce the shrinkage of clothes:
1. Use washing powder or soap as little as possible when washing clothes, and add some softeners appropriately.
2. Soak them in light salt water for about half an hour before washing, and then rinse them with cold water; for shrinking clothes, you can pull them into a large piece of cardboard and iron them to restore them to their original shape.
3. Dry cleaning.
Post time: Nov-10-2021