Textile cleaning - what does that mean?
The modern textile cleaning today has several possibilities to process textile materials. On the one hand, there is the chemical cleaning process in which clothes or curtains etc. are "washed" in a solvent. This is particularly useful for very sensitive materials which tend to swell or where the fibre or the binding dissolves in water. Also certain dyes are water-soluble and can therefore not be processed in water. In another process, wet cleaning, water is used. However, certain additives in the washing process reduce the swelling of the fibres, so that even materials that are only to be cleaned chemically can now be processed in water. Here very much expert knowledge is required, since this is not yet designated by most manufacturers as a care possibility and the risk is higher than with dry cleaning. The third process that every end consumer knows is the pure washing process. Here, the focus is on the fiber swelling, because dirt particles can be washed out of the fiber by opening it and by the friction of the materials. However, this is mainly suitable for robust fabrics with a high cotton content. In the final cleaning process, manual processing, the material is either so sensitive that machine cleaning is not possible, or the piece to be processed simply cannot be machined. Here, for example, large stuffed animals or suitcases etc. are to be mentioned. In the following, the individual cleaning procedures will be examined in more detail:
The chemical cleaning process
As an alternative to water, a solvent is used to rinse the textiles, dissolving and removing the dirt. The process works as follows:
It is first sorted by colour (dark, medium, light and red). The textiles to be cleaned are then fed into the cleaning machine. From the outside, it looks like an oversized washing machine. Now a solvent, hydrocarbon solvent (KWL) or perchloroethylene (PER), is pumped from a tank into the drum. The textiles are then moved in this bath in the same way as in the washing machine at home. Depending on the fabrics, a cleaning booster is added, which can bind certain contaminants better than the solvent could. After the bath, the fabrics are spun slightly so that the soiled solvent is hurled out. This is then pumped into distillation. In the next bath, clean solvent is pumped into the drum again and the textiles are rinsed clearly in it. The solvent is then pumped off and the textiles are spun off. Directly afterwards, the garments and other materials are then gently dried until a calibrated measuring instrument determines that the residual concentration in the circulating air is so low that the fabrics can be removed without hesitation. The solvent from the prewash, which was pumped into the distillation, is distilled and then pumped back into the clean tank. Only the actual dirt remains in the distillation and a negligible residual amount of the solvent. In this respect, the only waste produced in this process is the dirt that remains in the distillation. The solvent itself can be used again and again. Disposal is then carried out by a qualified disposal company. Finally, the distillation waste is incinerated with other residual waste in a combined heat and power plant (only possible with KWL).
In the wet cleaning process, water is used to rinse the textiles, but additives should prevent the fibres from swelling and the material from shrinking due to too much mechanics. Here the procedure is as follows:
The textiles are put into the wet cleaning machine, which initially looks similar to a larger domestic washing machine. Before this, however, various tests should be carried out to determine whether the dyestuffs are water- or soap-resistant. You should also pay attention to bonds and other applications to avoid unpleasant surprises. The clothes or fabrics are sorted beforehand according to colour and material. In spite of the low mechanics of the process, colourisations and fibre transfers could occur. Depending on the type of fabric, a very small amount of water and cleaning solution is now given into the drum. It is important here that there is not too much pure water present, which could lead to fiber swelling in the product. The precisely dosed amount of water and cleaning solution with swell protection now wets the textiles in the machine. In order to control this reliably for each cleaning process, a pump system controlled by the machine is used, which always only uses the exact amount of detergent required. To avoid fibre displacement, size changes or pilling, very little mechanical equipment is used for washing. The cleaning solution is pH neutral or even slightly acidic to protect the colouring and prevent bleeding of the fabric. The subsequent rinsing of the textiles also takes place with a small amount of water, little mechanics and the addition of an agent to prevent fibre swelling. Furthermore, it is also possible to add a fibre protection which keeps the fibres flexible and enables a better smoothing of the fabric during ironing. This process is particularly suitable when water-soluble soiling is present on a large scale or when sweat and body odours cannot be sufficiently removed in the chemical process.
This is the well-known washing process in which a cleaning effect is to be achieved by means of water, a detergent and varying degrees of fibre swelling. The generally known washing process works as follows:
The textiles are checked for washability (laundry symbol wash tub) and fed into the drum. The textiles are sorted according to colour and material. The temperature is determined by the garment with the lowest washing temperature. Only materials of a similar type should be washed together. Fine fabrics should not be washed together with rougher materials in order to avoid roughening the surfaces. Velcro fasteners should also be either covered or washed with robust fabrics only. The washing process itself is divided into the prewash (if necessary), the main wash and the rinse cycles. In the washing process itself, the fibres should swell and the dirt should be released into the washing solvent by friction. The detergent binds the contaminants and during draining and spinning the dirt is then washed away in the solvent. Finally, the rinsing cycles remove the remaining soluble dirt particles and the excess detergent. After spinning, the fabric can then be dried in a tumble dryer or hanging, depending on the material.
If no mechanical process is possible, the only last option is manual processing, which is usually very labor-intensive and should only be carried out with a great deal of expertise:
There are simply too many possibilities here to describe a general procedure. Depending on the material, the sponge, brush or spray extraction device is used. The cleaning detergents to be used must be selected with regard to colour fastness, fibre swelling tendency and fineness. Furthermore, the type of soiling is of course decisive when it comes to the right cleaning detergent or solvent for processing. Especially here, the operator must be very experienced in order to correctly assess the materials and soiling and avoid damage due to too much mechanics, the wrong cleaning detergent or too long exposure to water (fibre swelling). Here, one can speak of the supreme discipline in the field of textile cleaning