1 raw material defects
The raw material evenness is uneven, the belly yarn is obvious, there are too many thick and thin yarns and joints, yarn knots, foreign fibers, poor network yarn, poor quality of spandex covered yarn and uneven mixing of blended yarn. , may lead to fabric degradation. All kinds of raw material defects that affect the appearance quality of textiles belong to raw material defects. The purpose of promotion can be achieved by repairing inspectors, who must make necessary repairs.
Due to the poor quality of raw materials, the quality of textile products is often greatly discounted, mainly because the appearance quality inspection of finished products is not placed in an important position during sample confirmation and cylinder sample confirmation, and some colors are not convenient to find the quality problems of raw materials. In the repair process, the repair method must be reliable, and it is not allowed to damage the fabric surface during the repair process, causing new irreparable defects and seriously affecting the appearance quality of textiles. Sometimes an appearance defect is easily overlooked by all inspectors before it is discovered. When the customer finds this defect on the ship sample and puts forward suggestions for repair, it is very likely that the products of this order have all completed the inspection and packaging process, and the confusion brought by rework to the inspection site can be imagined, which is far more harmful to the enthusiasm of all inspectors than to their physical strength. Dyeing and finishing merchandisers need to step forward at this time, patiently do the ideological work of all inspectors, and complete the repair work with good quality and quantity on the premise of ensuring the delivery date of products. Protect the packing box from damage as much as possible when reworking.
2 weaving defects
No matter what kind of weaving equipment, weaving defects will occur. There are many reasons for weaving defects, such as equipment itself, raw materials, temperature and humidity of environment, technical level of operators, fabric structure and so on. Take the woven fabric as an example, warp and weft broken ends, weft shrinkage, parking marks, weft stops, joints, warp and weft dislocations, too dense or too thin weft, loose selvage, loose winding shaft, too narrow loom width and wrong weave structure are all common defects in weaving. Some of the above weaving defects can be repaired, while others cannot. For those irretrievable knitting defects, methods such as hanging thread to give way to yards, cutting and assembling can be adopted to improve the product grade. For serious defects with large length, cutting must be carried out.
3 Pretreatment of defects
Different varieties have different characteristics of pretreatment defects. For all-cotton or polyester-cotton bleached fabrics, it is very important whether their degree is qualified or not. For polyester strong twist fabrics, the strength after alkali deweighting is a very important issue. However, the problem of strength damage is still an important problem for burnt-out polyester-cotton products, bio-enzyme polished sanded cotton fabrics and lyocell fabrics. Defects in pretreatment process are sometimes not found in this process, such as yellow spots on the surface of polyester fabric after reduction and unclean effluent.
Will dirty desizing of cotton fabric occur on the surface of dyed fabric? Plasma head marking? If the scouring is not clean, cottonseed hulls will remain on the surface of the fabric and so on. For inexperienced inspectors, these defects may all be considered as dyeing defects.
On the other hand, whether it is pretreatment defects or dyeing defects, inspectors should make corresponding treatment when they find these defects, which is the top priority of product appearance quality inspection.
4 Dyeing defect
For textile inspection, it is relatively simple to find dyeing defects. Dyeing defects have the characteristics of different colors and irregular shapes from fabric surface background color. Stains, spots and marks are the most common dyeing defects. Finding these defects, clearly marking them and properly handling them according to the inspection standards are the basic requirements. In the dyeing process, it is very likely that the fabric will be blocked or broken for various reasons, especially the blocked cylinder will cause great damage to the fabric, resulting in such problems as? Chicken paw prints? Or Xiaoshan people? Braking pollution? Defects. This defect is difficult to repair.
Sometimes some wool-like varieties add cold water quickly in the dyeing and cooling stages because of the special raw materials, which will produce many similar products on the fabric surface. Chicken paw prints? Defects. This kind of wool-like products will also produce the above defects on the fabric surface if the fabric is too much or the dehydration time is too long. About the fabric surface? Delicate flowers? This kind of defect needs special attention of inspectors. If such defects are found, they should be reported to the dyeing and finishing merchandiser in time, and the merchandiser will decide the inspection method of such defective products according to the severity of the defects.
5 finishing defects
Due to the diversity of finishing, finishing defects also show diversity. For textiles with appearance finishing, sanding finishing, napping finishing and biological enzyme polishing finishing are common processing methods. The length, density and uniformity of fluff are the main indexes to test the quality of the above three kinds of finishing. For the resin finishing of cotton fabric, the problem of fabric strength damage can not be ignored.
For the functional finishing of fabrics, satisfactory and convincing inspection results cannot be obtained through appearance inspection. For the soft finishing of most fabrics, there are two points that need special attention in appearance inspection. The first is whether? Drawing? Or? Split? The second is the presence or absence of fabric surface. Silicone oil spots? . When softening textiles, padding softener is usually used to improve the feel of fabrics. Too much softener in fabric will obviously reduce the friction coefficient between warp and weft. Under the action of external force, the warp yarn can be obviously displaced along the weft yarn and produced on the fabric surface. Drawing? Or? Split? Phenomenon. At present, silicone series softeners are widely used, and most of them are emulsion softeners. When the processing environment temperature is too high or the softener emulsion is stored in the workplace for too long, demulsification will occur.
If the softener is not found in time after demulsification and continues to be used, it will stick to various rollers of dryers, setting machines or rolling mills. This will cause serious roll sticking of light-colored textiles for subsequent processing.
After the light-colored fabric sticks to the drum, it will produce a lot on the surface of the fabric. Soft marks? . ? Soft marks? It can be repaired, but if it is not repaired properly, it will cause more damage to the fabric surface. Pollution? .