Ink Printing Failures and Remedies (II)

4. Graphic crushing Main reasons:
1 poor print quality;
2 Pressing contact is too tight;
3 ink viscosity is too high;
4 The ink is not evenly stirred.
Remedy:
1 pad version and adjust the level of printing balance;
2 adjust the printing pressure;
3 adjust the viscosity and switch to low viscosity ink;
4 Reasonably mix ink.

5. Overprinting is not allowed
1 The difference between the PH value of the substrate and the PH value of the ink is large, especially the surface tension is not balanced;
2 The first color pressure is too high or the viscosity is too high;
3 The first color ink film formation is too fast;
4 background is too smooth,
Remedy:
1 control or choose substrates with almost the same surface tension or close PH value;
2 The second-color printing pressure increase or the second-color printing pressure should lightly or dilute the first-color high-viscosity ink;
3Adjust the dryness of the first color ink, especially the microreinability of the film with the second color ink (do not try to crystallize the first color, that is, after the mirror surface is not completely dried, print a color) .

6. Graphically blurred
1 bad quality of the plate;
2 ink viscosity;
3 ink dispersion is not good;
4 plate and ink roller contact too tight.
Remedy:
1 plate to be smooth or smooth;
2 Adjust the viscosity of the ink and control it in 25-35S/coating -4 cups;
3 fully stir the ink;
4 Adjust printing pressure.

7. Insufficient transfer
1 Insufficient printing pressure;
2 The hardness of the flexographic plate is not enough, the gravure (text) is too deep or the anilox roller is blocked;
3 water-based paper is too strong;
4 ink loss, aging;
5 poor ink flow.
Remedy:
1 increase the pressure;
2 Check the hardness of the flexographic plate should be 42 ± 3% as well, replace the gravure (required for 25-45 micron to replace the elastic flexible version) or eliminate the anilox roller, gravure block;
3 use strong hydrophobic ink;
4 Clean the ink spots on the dried plate, and pay attention to the surface treatment of gravure rust.

8. Imprint resistance: Main reasons:
1 ink film is not water resistant;
2 is not resistant to light;
3 is not wear-resistant (refers to the printing ink ink film dry).
Remedy:
1 exchange the new ink or make up the resin solution (the PH value is controlled between 8-9.3);
2 Replace lightfast ink or add anti-ultraviolet absorber;
3 Use an appropriate amount of ink (such as acrylic or add calcium).

9. Ink film pinhole Main reasons:
1 Chemical pinholes (1) Insufficient or excessive defoamer; (2) Ink dilute too much: (3) Ink of low viscosity ink is too much; different pinhole locations, different sizes and quantities are also different;
2 Mechanical pinholes (rough layout or ink rollers are defective or unintentional) The pinholes will repeat in the same area, in the same area and in the same number.
Remedy:
Chemical pinholes:
1 Add an appropriate amount of defoamer;
2 should be incorporated into the original ink.
Mechanical pinholes:
1 Airprint run-in or replace printing plate;
2 Correct the ink roller and adjust the printing pressure.

10. Ink blistering Main reasons:
1 Defoamer deficiency or excess;
2 ink dilute too much;
3 Low-viscosity inks are inked with excessive ink; poor ink foam inhibitors or insufficient circulation of ink; or leaky pipes.
Remedy:
1 Defoamer should be controlled at about 0.2%;
2 increase the circulation of ink;
3 Replace the pipe or repair the damage;
4 The ink is best stored for 48 hours before it is used (wait for the foam to disappear and stabilize).

11. Ink gelation Main reasons:
1 with wrong solvent;
2 mixed with different types of ink;
3 poor storage environment;
4 Ink deterioration over time.
Remedy:
1 Use a good solvent, especially the appropriate amount of cosolvent (ethylene glycol, glycol ethers);
2 select the same performance, with the brand manufacturers of ink, the deployment of base color ink;
3 It is necessary to accurately place the ink when adjusting the ink.
4 After the ink is sealed and stored in a dry and ventilated and dry place;
5 Replace ink (add TM-3 or inorganic salt anti-gelatin in ink).

12. Plate wear Main reasons:
1 contact too tight;
2 Ink has coarse particles;
3 paper dust mixed with ink (especially ink fountain);
4 printing pressure too heavy;
5 The quality of the plate is poor.
Remedy:
1 Re-adjust the contact;
2 filter ink;
3 cleaning ink fountain (or regular);
4 adjust the pressure;
5 re-version.