1. Among eva-40w, MP-45 and cl-pp resins, cl-pp often brings about high solvent residues and eva-40w brings about low solvent residues. Therefore, under the condition that the composite strength can be guaranteed, the content of cl-pp can be appropriately reduced and the content of eva-40w can be increased.
2. Select appropriate cl-pp. The solvent residue caused by cl-pp from different packaging box printing manufacturers in the composite ink varies greatly. If the formula cost is acceptable, pp803mws produced by Japanese paper can be selected. Under the condition of the same dosage, it can generally be reduced to 50%.
3. When dissolving eva-40w, MP-45 and cl-pp, adding a part of ethyl ester and residual solvent reducing agent can effectively reduce the residual amount of toluene solvents in the ink film.
4. Check whether the solvent used for the ink and the solvent used for the printing machine brush are pure. If there are a few high boiling point solvents, it may also cause excessive solvent residue, and even cause serious peculiar smell in the printed matter.
5. Conditioning in the process of packaging box printing and compounding:
① Toluene solvent shall be used as little as possible when manufacturing dilution solvent, and the mixed solvent of toluene: acetic acid: butanone =2:5:3 can be selected;
② In the process of packaging box printing, improve the exhaust air in the drying channel of the printing machine, and appropriately improve the temperature of the drying channel. If conditions permit, open the drying channel for repeated drying after white ink printing;
③ In the process of packaging box printing, the viscosity of ink can be properly reduced.
