Heat-setting fabric is divided into dry and wet two types
Dry heat setting:
Fabric in the heating chamber by the hot air heating, seal is pulled to a certain size,Out of the heating chamber then cooling, so that the temperature dropped to the fiber's glass transition temperature, resulting in a stable size, such as polyester and other fabrics, the temperature is generally 180 ~ 210 ℃, time 20 ~ 30 seconds.
Wet heat setting:
There are hot water bath and steaming two, hot water bath is the fabric in boiling water or high pressure cylinder treatment, and steaming the fabric is wound on a perforated roll steam steaming, nylon fabric commonly used hot and humid stereotypes, at high pressure Cylinder temperature 125 ~ ~ 135 ℃, treatment 20 ~ ~ 30 minutes.
Heat setting can make the fabric size stability in a certain degree of setting,The stereotypes pre-programmed tension control program, after the finished product washing, or drying by mechanical force, stereotypes plus pre-tension to eliminate, they will reply before the size of stereotypes, The difference in the process of change, known as shrinkage, including straight and lateral changes.
Shrinkage has negative and positive values, while fabric area shrinkage, representing the rate of change in area of the fabric in both the horizontal and vertical directions, is also equal to the sum of the lateral and direct shrinkage minus its product,If the area shrinkage is less than 10%, the area shrinkage will approximate the sum of the shrinkage in the straight and horizontal directions.Fabric shrinkage due to raw materials, fabric and processing methods vary, there are differences,
The horizontal and vertical shrinkage rate to determine the resilience of the fabric is a bit difficult,Only to observe the fabric dyeing and finishing the size of each process change decision.
To control the fabric shrink to a certain extent, the residual shrinkage in a certain degree of control, this process is finishing an important part of processing.