Troubleshooting method of UV coating machine

    Troubleshooting method:

    1) Small particles of impurities appear on the surface of the glazing print

    Cause of failure: Impurities have been mixed into the glazing paint.

    Solution: The glazing paint should be filtered before use. Before glazing, the paint bucket and rubber roller of the glazing machine should be cleaned to avoid mixing of dirt.

    2) Poor gloss of glazing film

    Causes of failure: a. Low temperature during coating drying and calendering; b. Poor coating quality and low gloss after film formation; c. Low coating concentration and insufficient coating amount, and coating is too thin.

    Solution: a. Adjust the drying temperature of the glazing coating to increase the calendering temperature; b. Change the coating, or increase the concentration of the coating, and increase the coating amount; c. Secondary coating can be used.

    3) Streaks or wrinkles appear on the film surface

    Causes of failure: a. The glazing paint has a high viscosity; b. The amount of glazing paint is too large; c. The glazing paint has poor wettability of the ink layer on the surface of the printed matter; d. The rubber roller and impression cylinder of the glazing machine The pressure is uneven between.

    Solution: a. Add a small amount of thinner to reduce the viscosity of the paint; b. Reduce the coating amount of the glazing paint; c. Adjust the pressure between the rubber roller and the impression cylinder of the glazing machine to eliminate streaks.

    4) After the printed matter is calendered, the surface is easy to fold and crack (thick paper is more obvious)

    Causes of failure: a. The temperature in calendering is too high, which reduces the moisture content of the printed matter and the paper fiber becomes brittle; b. The pressure in the calendering is large, which makes the extensibility and flexibility of the printed matter worse; c. The selection of post-processing conditions is inappropriate D. Poor processing suitability after glazing paint.

    Solution: a. Reduce the calendering drying temperature, and take effective measures to change the moisture content of the printed matter; b. Reduce the calendering pressure; c. Adjust the processing conditions to make it the same as the printed matter (after calendering) match.

    5) After calendering, the blank part of the printed matter is light-colored, and the light-colored part is discolored

    Causes of failure: a. Ink drying is poor, and the ink layer has poor solvent resistance; b. The coating solvent has a certain dissolving effect on the ink layer; c. The coating layer is not completely dried and the solvent residue is high.

    Solution: a. After the printed matter is dried, glaze; b. Reduce the amount of solvent in the glazing paint (solvent that can dissolve the ink), and the solvent can be changed or the paint can be replaced if conditions permit; c. Increase the drying temperature and reduce the coating Residual amount of internal solvent.