To overcome the problem of large shrinkage of cotton knitted fabrics, the following measures and methods can be taken in combination with the characteristics of knitted fabric printing in the state of slitting and open width:
⑴ Loose processing. Minimize the tension of each process in the printing and dyeing production process, try to avoid the plastic deformation of the fabric in the wet state, and avoid the elongation of the fabric and fiber. This is the most ideal method to prevent the fabric from shrinking.
In fact, printing companies have adopted a lot of loose processing methods in the dyeing and finishing of knitted fabrics. Regardless of the current selection of knitted fabric printing and pre-treatment and post-finishing equipment, many effective loose processing methods have been taken into consideration. Process well. It is believed that with the development of knitted fabric printing and knitted printing equipment, the loose processing of knitted fabrics will continue to be improved and improved.
In addition, the shortening of the printing process has also attracted attention in production and put it into production practice. The adoption of the above measures will definitely reduce the plastic deformation of knitted fabrics in the wet state, and will inevitably prevent the elongation of fabrics and fibers. , it is very beneficial to reduce the shrinkage of the fabric.
⑵ Overfeed drying. That is, to relax and dry, reduce the tension effect, and make the fabric approach a full equilibrium state.
Before the printing of knitted fabrics, overfeed drying can be combined with the pre-printing tenter setting process, so that overfeeding can be mastered in a timely manner, and the fabric can be dried to reduce the shrinkage rate of the fabric.
(3) Mechanical pre-shrinking. It is carried out on special mechanical pre-shrinking equipment.
First, overfeed the fabric to allow the fabric to have room for pre-shrinking in a relaxed state in the longitudinal direction, and then wet the fabric with steam to enhance the plasticity of the fabric in a relaxed state, relax the internal stress of the fabric, and then make the fabric longitudinally through diffusion. Shrinkage, lateral expansion, or longitudinal extrusion, to force the retraction of the longitudinally elongated portion of the fabric during weaving or dyeing and finishing. The fabric has a relaxed structure and is loosely dried in this state to achieve the effect and purpose of pre-shrinking. Mechanical pre-shrinking is one of the effective measures to overcome the large shrinkage rate of knitted fabrics.
At present, there are knitted fabric pre-shrinking machines for circular knitted fabrics and open-width knitted fabrics. Generally, only pre-shrinking machines for slitting and open-width fabrics are used for knitted fabric printing.