Common printing problems of printing machines
Aug 11, 2022
The following will share with you the common printing fabric problems of printing machines:
1. Uneven printing color (spots): Part of the printing has become mottled like the shape of the skin of the sand fish. This defect mostly occurs when the viscosity of the color paste is not appropriate, the mesh of the screen is not properly selected, or the patch is not uniform.
2. Bleeding (dissolving): The color of the printed pattern bleeds out, the outline of the pattern is not clear, and the color is blurred. It is caused by the low viscosity of color paste, extremely thick dye concentration, excessive amount of printing paste or excessive amount of hygroscopic agent.
3. Color-matching stains (color-matching): stains caused by the color of the printed pattern contaminating other parts. Most of them occur when the printing platen is not clean, the drying after printing is not sufficient to overlap each other, or the fabrics are in contact with each other in the steaming process. In Japan, some factories perform thorough washing under rope conditions using a controlled method of adjusting the tension of the fabric.
4. Insufficient color paste (desizing): that is, the color of the pattern part is lacking. It usually occurs when the color paste is not replenished in time, the pressure of the squeegee is uneven, the hardness of the squeegee is improper, the relay of the squeegee is faulty, the surface of the printing platen is uneven, and the viscosity of the color paste and the slurry are not appropriate.
5. Bad pattern joint (joint printing): the pattern overlaps or does not match (disengages) at the joint of the pattern. It is mostly caused by the poor adjustment of the conveyor belt or the improper adjustment of the table version, which affects the accuracy of the flower position.
6. Misalignment of the pattern (crooked set, inaccurate set): It is a printed product with a misaligned pattern. Most of them occur in cases of inaccurate flower alignment, poor carving, and poor patching.
7. Partial embrittlement: On printed fabrics, areas printed with one or more colors are often damaged, usually due to excessive use of damaging chemicals in the printing paste. This problem can also be found in the discharge area of printed fabrics.
