Causes and solutions of problems with dyed fabrics and printed and dyed fabrics

Mar 27,2023


 Causes and solutions of possible problems in the production process of dyed fabrics

  1 Weaving defects

  Weaving defects in the warp or weft direction appear regularly or irregularly on the fabric.

  Main reasons:

  ① The strength of the yarn used is not enough.

  ② The yarn is poorly sized (light or heavy).

  ③ Weaving equipment is poor (when the weaving equipment fails, it will cause problems such as broken yarn).

  ④ The repair of the off-machine grey cloth is not complete.

  ⑤ The acceptance of the finished product is not careful.

  Solution: Strengthen the repair.

  2 Latitude oblique/latitude arc (including size grid)

  For woven fabrics and knitted fabrics with 2% weft slant/weft arc, and all fabrics with more than 3% crooked can not be classified as first-class products.

  Main reasons:

  ① Poor weaving equipment (when the weaving equipment fails, it will cause a lot of downtime, resulting in weft inclination/weft arc)

  ② Mainly refers to the weft inclination/weft arc caused by poor finishing equipment).

  ③ Poor finishing (weft inclination/weft arc caused by the operator's irresponsibility during finishing).

  Solution: Strengthen repair and rearrangement (weft correction).

  3 The shrinkage rate is large

  When the shrinkage rate of the warp and weft directions of the fabric exceeds the specified value, it cannot be designated as a first-class product. Different fabrics will have different ranges.

  Main reasons:

  ① Poor sorting after finishing.

  ② Poor pre-shrinkage equipment.

  Solution: pre-shrink again (within the specified shrinkage rate)/fabric shrinkage washing, etc.

  4 The feel is not consistent with the standard

  The feel of the finished fabric is inconsistent with the feel of the standard sample, and there are obvious differences.

  Main reasons:

  ① Poor sorting after finishing.

  ② The raw materials are incorrect.

  ③ The production process is incorrect.

  Solution: Reorganize/reproduce.

  5 Unqualified color fastness

  The color fastness of fabrics (yarn-dyed fabrics and dyed fabrics) cannot be consistent with the requirements

  Main reasons:

  ① Poor dyeing process.

  ② The dyeing raw materials are poor.

  ③ Poor sorting after finishing.

  ④ Poor operation. (Especially obvious when paint scraping/paint dyeing)

  Solution: re-fixing finishing/re-producing fabrics/re-dyeing (dyed cloth is OK)/color repairing (paint scraping/paint dyeing fabrics are OK).

  6 The fabric style cannot be consistent with the standard sample

  The style of the fabric is obviously different from the standard sample (bamboo style/segment dyeing style/thickness, etc.).

  Main reasons:

  ① The raw materials are incorrect (the slub yarn is incorrect/the yarn count is incorrect)

  ② The production process is incorrect (the process of segment dyeing is incorrect/the arrangement of slub yarn or segment dyeing yarn is incorrect)

  ③ The post-finishing process is incorrect (when the raw materials and organization are correct, whether the post-finishing process is correct or not will affect the style of the fabric)

  Solution: ① Re-production of fabrics ② Re-finishing.

  Causes and solutions of printing and dyeing cloth defects (dyeing problems)

  1 skirt wrinkle

  The wrinkles are parallel to each other and flush head and tail.

  The wrinkles are large in the middle and pointed at both ends. There is a shuttle tail at the junction of the wrinkles and the plane, which is shaped like a skirt wrinkle.

  Skirt wrinkles mostly occur on fabrics containing chemical fibers, and are not easy to find on the original grey cloth. It only appears after printing and dyeing.

  Main reasons:

  ① The difference in the performance of the chemical fiber itself or the inconsistency of the high temperature set twist temperature in the textile factory, resulting in different weft shrinkage rates;

  ② There are differences in the number or twist of weft yarns used.

  Solution: re-cast the original grey cloth production.

  2 seam head wrinkles

  The wrinkles are connected to the seam head, one or more of different lengths. Some are at one end of the seam head, and some are at both ends of the seam head.

  The main reason is that the sewing head of the cloth feeder is not good. The sewing head is not straight, firm, flush, and the stitches are uniform.

  Solution: Together with the seam head opening and cutting, make the next zero cloth treatment.

  3 Printing and dyeing processing wrinkles

  Generally, there are not many strips on the cloth surface, usually straight or oblique strips, with different lengths and widths. The wrinkles produced before printing and dyeing or during the printing and dyeing process are quite different from normal, and the color of the cloth surface is quite different; the color difference of the wrinkles produced during the washing process after printing and dyeing is fixed is small.

  Main reasons:

  ① There are original wrinkles in the first half of the product before printing and dyeing;

  ② During the printing and dyeing process, the mechanical tension and roller pressure are not well adjusted; the parallelism of the guide roller and the drying cylinder is not well mastered;

  ③ The preparation is not well done for cleaning.

  Solution: Reproduction.

  4 mercerized wrinkles

  After printing and dyeing, it presents shallow, straight or oblique fine dead wrinkles on both sides of the middle depth

  Main reasons:

  ① Mercerizing machine to alkali steamer, flat washing tank cloth guide roller uneven or stained with yarn head, alkali scale;

  ② The tension adjustment of the mercerizer is improper;

  ③ The direct steam pipe of the alkali removal steamer is opened, and the large impact fabric causes wrinkles.

  Solution: supplementary production.

  5 Styles

  The exposed part of the printing and dyeing fabric is different from the normal color of the cloth surface. Irregular light-colored stops or strips generally appear on the folds of the cloth or on both sides of the cloth web.

  Main reasons:

  Some printing and dyeing semi-products used for reactive dyes and disperse dyes, alkali on the cloth of the product, or the action of reducing gas in the air affects the fixation of the fabric and the dye, and the exposed part produces a light color profile. Reactive dyes are prone to wind marks.