How to Control Solvent Residual Volume in Gravure Printing Soft Packaging (3)

In general, the amount of solvent adsorbed by PA and PET is smaller than that of PP.
7. Other factors

(1) If the newly printed product can adopt an effective treatment method in time, it will also reduce the residual solvent. Therefore, after the printed product is printed, it is advantageous to control the residual solvent by placing it in the ventilated place for one or two days and recombination.

(2) In the printing process, a color group with a deeper color of the printing plate and a color group with poor solvent volatility may not be printed with the ink and may be subjected to secondary drying, which is advantageous for reducing the residual amount of the solvent.

(3) For multi-color printing, do not use too many overprint colors when designing the pattern. Use spot color ink as much as possible to prevent overprinting of the local ink layer.

(4) If the same printing plate has both a solid ground color and a very shallow layered Chinese printing and packaging network, it is extremely difficult to control the amount of residual solvent. When the volatilization rate of the solvent is increased, the shallow mesh will block the plate, and when the volatilization rate of the solvent is reduced, there will be a large amount of solvent residue in the solid. Therefore, this design should be avoided when making plates.

(5) When designing a flexible packaging product structure, the poorest barrier film should be used as a printing layer as much as possible, and a barrier layer and a heat sealing layer with a relatively high barrier property should be compounded inside, so as to avoid contamination of the contents by the residual solvent.

When the amount of residual solvent exceeds the standard, it can also be remedied by ventilation and drying.