In the textile industry, some customers find that the hand feeling of spot goods is different from that of the original products. It is because of the pre-shrinking, washing or sand washing. What are the differences among them?
1.Pre-shrink
The process to use physical methods to reduce the shrinkage of fabric after soaking in water is known as mechanical pre-shrinking finishing. Pre-shrinking is mainly to control the warp shrinkage of fabric. Before pre-shrinking, the warp shrinkage of fabric is generally 7~8%. After pre-shrinking, the warp shrinkage of fabric can reach national standard 3% or American standard 3%. Due to the different drying method, the requirement of American standard is higher. The American standard 3% is equivalent to 1% of national standard.
2.Wash
Washing is to add softener or detergent in the water and then directly put the fabrics in the water. It can be divided into light normal washing, normal washing and heavy normal washing according to the time of washing and the adding amount of softener. After washing, the fabrics will become very soft and have good handle. Also people will feel that the fabrics become thicker.
3.Sand Wash
Sand washing process is similar to washing process, but they are added different things. In sand washing process, generally it is to add alkali or oxidizing auxiliaries. And also there will be added moderate softeners. Adding alkali auxiliaries is to damage the surface structure of fabrics to achieve softer hand feeling after sand washing. Also there will be some fluff on the fabric surface. So after sand washing, fabric will become soft and napping. And the fabric will appear an illusion of becoming thicker. But this fabric will be easy to spill. It may break if pulled lightly. So thin fabrics are not recommended to be sand washed.
Post time: Jul-02-2024