General Procedures For Textile Appearance Quality Inspection

Inspection contents:

The appearance quality inspection of textiles starts with the accuracy of color.

The inspection procedures are as follows: checking the accuracy of color, raw material defects, testing weaving defects, pre-processing defects, dyeing defects and finishing defects, and deciding whether to cut or lower the code according to the standard requirements.

When the color accuracy test is controversial, the dispute can be settled according to the measurement result of the electronic color matching system.

1) raw material defects

There are obvious defects in raw materials such as big belly yarn, uneven evenness, excessive joint, yarn knot, foreign fiber, bad network yarn, poor quality of spandex coated yarn, uneven blending of blended yarn and so on, all of which may cause fabric degradation.

2) weaving defects

Weaving defects are caused by many aspects, such as the equipment itself, raw materials, environment, temperature and humidity, operator's skill level, fabric structure and so on, which will cause weaving defects.

Take woven fabric as an example, broken warp, weft, shrink, weft, stop, weft, joint, wrong track, wrong weft, weft density or too thin, loose edge, loose cloth, loose diameter, too narrow width of machine door and wrong structure, all belong to common defects in weaving.

3) pre-processing defects

The characteristics of different varieties and defects are different in pretreatment of dyeing factories. For cotton or polyester cotton bleached fabrics, whiteness is very important. The strength problem of polyester strong twist fabric after alkali decrement is very important.

The polyester cotton products processed by rotten flowers, polished cotton fabrics with biological enzyme polishing and Lesel fabrics are still important problems for the strength damage.

Sometimes the defects of the pretreatment process can not be found in the process. If the polyester fabric is reduced, the water will not be clean after the amount is reduced, and the macula will appear on the surface of the dyed fabric. If the cotton fabric is desizing, it will produce a "pulp trail" on the surface of the dyed fabric. If it is not cooked, it will leave the cotton seed hull on the surface of the fabric.

For inexperienced inspectors, such defects may be considered as defects or defects in weaving. But whether it is pre-processing defects or dyeing defects, the inspectors found that these defects should be marked and told in time.

4) dyeing defects

Dyeing defects are relatively simple, and dyeing defects on the fabric surface are different from the background color and irregular shape. Color spots, stains and color traces are the most common dyeing defects. The defects were identified and marked, and processed according to the inspection standards.

In dyeing process, it is possible to block or break the fabric for various reasons, especially the cylinder block will cause great damage to the textile and form the shape of chicken paw on the surface of the fabric. It is hard to repair such defects.

5) finishing defects

Collate defects show diversity. Polishing, finishing and polishing are common ways of processing. The length, density and evenness of the fuzz are the main indicators for testing the finishing quality. For the finishing of all cotton fabrics, the problem of fabric strength damage can not be ignored.

The functional finishing of fabrics can not obtain satisfactory and convincing test results through visual inspection. For most soft finishing fabrics, two points need to be noticed in appearance inspection. The first is whether or not to draw silk, and the second is whether there is oil stain on the surface of the fabric.

Textile softness finishing mostly improves fabric feel by rolling softeners. The excessive amount of softeners on the fabric will obviously reduce the friction coefficient between warp or weft yarns. Under the action of external force, the warp yarn can move more clearly along the weft yarn, resulting in the phenomenon of wire drawing on the surface of the fabric.

6) selection and implementation of standards

For all products, appearance inspection is an important part of the technical conditions in the product standard. Because of the variety of textiles, and what standards are used to test, after the processing agreement is signed between trade companies and customers, the inspection standards are clearly marked. While trading companies sign processing agreements with printing and dyeing enterprises, most of them refer to the standard of 4 points system, so that they have better operational performance.