The most common printing defects and their causes

Common printing defects and their causes

1 Exposed white

part of the warp or weft turns over or moves to the front and back of the fabric, showing a trace on the pattern that looks like being scratched. This defect is mostly caused by poor color paste penetration and improper treatment after printing (uneven tension, etc.)

2. The printing color is uneven (spots)

part of the printing has become spots like the shape of the skin of a sand carp. This defect often occurs when the viscosity of the color paste is inappropriate, the sieve is improperly selected, or the cloth is uneven

3. Oozing (melting)

the color of the printing pattern oozes out, and the outline of the pattern is not clear, showing ambiguous colors. The raw materials that can be used as beauty and nursing products are caused by the low viscosity of the color paste, the extremely thick dye concentration, the excessive amount of printing pulp absorption or the large amount of hygroscopic agent

4. Color matching stains (color matching)

stains caused by the color of the printing pattern contaminating other parts. Most of them occur when the printing table is not washed cleanly, the drying after printing is not sufficient, and they overlap with each other, or the fabrics are in contact with each other in the steaming project. In Japan, some factories use a control method of adjusting the tension of the fabric under rope conditions to thoroughly wash

5. Double color difference (uneven scraping)

is tied to the horizontal direction of the fabric, showing a certain interval of color depth. The defect usually occurs when the screen frame and scraper are installed poorly or the slurry is scraped unevenly

6. Insufficient color paste (desizing)

that is, the color of the pattern is lack. It usually occurs when the color paste is not replenished in time, the pressure of the scraping knife is uneven, the hardness of the scraping knife is improper, the relay of the scraping knife is faulty, the surface of the printing table is concave convex, the viscosity of the color paste and the size are inappropriate, etc

7. The pattern joint is poor (plate seal)

the pattern at the pattern joint of the pattern overlaps or does not match (detaches). It is mainly caused by poor adjustment of the conveyor belt or improper adjustment of the regular eye of the table plate, which affects the accuracy of the flower position

8. Pattern dislocation (crooked and inaccurate pattern)

is a printed product with pattern dislocation. Most of them occur under the conditions of inaccurate flowers, poor carving, poor cloth pasting, etc

9. The version can be divided into manual control and microcomputer servo control experimental machine; According to the position of the oil cylinder, the frame marks (frame print, lap off)

the printing part shows abnormal stripes in the shape of the pattern frame. It is mainly caused by poor conveyor belt and poor installation of pattern frame

10. Bending (flower shape skew)

that is, the pattern is inclined or curved to the warp and weft yarn of the fabric. It usually occurs when the printed grey cloth (silk) itself has weft skew or poor sewing head or the tableboard is attached with fabric skew

11. Color dots

are dot shaped color stains. It usually occurs when there are undissolved dyes in the color paste or impurities attached

12. Friction stain (color dragging)

refers to the defect formed by contacting foreign matters when the printing pattern is not fully dry, rubbing the color of the pattern part and contaminating other parts. This defect often occurs when the printed fabric is not fully dried and is dragged or touched by something due to carelessness

13. Dye splashing (version bouncing, splashing, scattered pulp contamination)

is the color spot contamination caused by color paste splashing. This defect often occurs in the cases of high processing speed of roller printing, improper plate starting action in screen printing, inappropriate viscosity of color paste, etc

14. Yarn tail contamination

is a yarn like stain caused by the yarn tail of printed blank silk (cloth) on the printed fabric. It is mainly caused by poor yarn treatment of printed blank silk (cloth)

15. Deep edge (medium depth, deep and light edge)

that is, the hue or depth of both sides and one side of the cloth is different from that of the middle of the cloth. It is caused by poor fabric scouring and bleaching engineering, poor installation of screen frame and scraper, uneven pressure of scraper, and improper dip rolling or coloring engineering

16. Joint color matching (joint color matching)

refers to the defect formed by the joint color matching of fabric or the joint of printed interlining on the cloth surface. It usually occurs when the joint of fabric or printed interlining is too large or the seam overlap is too large

17. Printing water stains

are stains or spots caused by water droplets. This is because the fabric is 16. 5% after printing and before the end of steaming On the other hand, the machine structure: 4-column frame structure and portal frame structure (optional) are caused by dripping condensate or splashing water droplets within a period of time

18. Scraper streaks

refers to the band like defects in the radial direction in roller printing. The defect occurs when the pressure of the printing scraper is insufficient or there are impurities attached

19. Printing crease

refers to the strip-shaped unprinted part of the printed fabric due to the wrinkle. Most of them occur due to the wrinkling of printed grey cloth, poor seaming head, excessive fabric sticking tension and the wrinkling of printed interlining

20. Unsmooth color removal or poor anti dyeing

refers to the unclear effect of white removal, color removal or anti dyeing printing. It usually occurs when the anti discharge pulp, color pulp, scraping pressure or hair color (steaming) conditions are improper

21. Paste dry crack (Fig. 23)

is a pattern defect caused by paste cracking after printing. Most of them are caused by improper post-processing or inappropriate viscosity of color paste

22. Rope streak

a streak formed by leaving traces of rope or rod used in steaming engineering on the printed cloth. It usually occurs when the temperature of steaming engineering is too high or the finishing and setting temperature is too low

23. The rope shaped color bar

is the discoloration or contamination caused by the contact of the printed cloth with the rope or rod in the steaming project. It is usually caused by steam condensing on rope or rod

24. Needle shedding or clip dropping marks

are defects caused by the falling off of the needle or clip of the tenter or the abnormality on the inner side. It is mainly caused by poor needle clips or cloth clips of the stenter, abnormal track and abnormal fabric width

25. White spots

are defects caused by the failure of printing color paste on part of the pattern. It usually occurs when foreign matters are attached to the screen film or yarn knots and foreign matters on the fabric make the color paste unable to be printed

26. Flapping

refers to the defect that exposes the white background when stretching or bending the fabric. It usually occurs when the paste viscosity, sieve size, scraping pressure and other conditions are inappropriate, resulting in poor penetration of the paste

27. Ripple defect (cloud spot)

refers to the defect with ripple on the printing pattern. It usually occurs when the silk of the screen or the pattern groove of the printing drum overlaps with the yarn structure of the printed fabric and interferes with each other