The most important part of reactive digital printing

The most important part of reactive digital printing

In fact, the most important part of reactive digital printing of knitted fabrics is not the printing, but the shrinking. If we do this well, it will be relatively easy.

Compared with woven fabrics, knitted fabrics are looser, and the fabrics are easily deformed and skewed, and often the skewed printing becomes more and more serious, or the width of the fabrics becomes smaller and smaller, causing serious quality problems. Loose fabric characteristics create a unique style for knitted fabrics, but increase the difficulty of fabric processing.

The key to reactive digital printing knitted fabric pretreatment is to make the fabric as close as possible to woven fabric. How to compute preprocessing in place?

There are several steps from purchasing knitted fabrics from fabric companies to real printing: opening -> bleaching -> preshrinking -> sizing.

When purchasing knitted fabrics, the fabric is in the shape of a barrel and needs to be opened with a slitting machine. When cutting the cloth, the loose cloth should be placed for 24 hours. During this process, comb the burrs on both sides as you cut.

Bleaching is the physical and chemical reaction of certain elastic strips on the pointer fabric under the action of temperature and compounds, and all or part of it is removed.

The next step is the key step, pre-shrinking. Compared with woven fabrics, digital printing of reactive knitted fabrics is especially important in this step. At this time, attention should be paid to the control of the weight, and the burrs on both sides of the shape and shape should be smooth, so that the printing is not easy to rub the nozzle. Knitted fabrics are really difficult to control, especially pure cotton and rayon, and the hygroscopicity of the fabric must also be considered, which will increase the weight a lot.

It is generally required that the shrinkage rates in both warp and weft directions be less than 3%. In addition to obtaining stable dimensions, pre-shrinking can also improve the feel and eye feel of the fabric, so that the fabric can meet certain requirements for weight and stiffness.

Especially the fabrics of cellulose fibers such as cotton, hemp, silk, viscose, etc., these fibers are easy to swell, shorten the fiber length, and affect the dimensional stability of the fabric and its blends. Preshrinking is the focus and difficulty of digital printing of knitted fabrics.