At present, the packaging and printing of milk powder is mainly based on plastic composite flexible packaging, and metal cans are also used. Plastic composite flexible packaging printing is basically printed on BOPP film or PET film, and then compounded with aluminized film or aluminum foil and heat sealing material.
For general milk powder packaging, chlorinated polypropylene resin inks are mainly used for printing. Although ink manufacturers have adopted various methods to adjust the ink structure and reduce the residual of benzene-based toxic solvents in packaging, there is still a small amount of residue in the packaging. . In order to completely eliminate toxic solvent residues, some companies have used benzene-free inks for printing. However, due to the quality problems of benzene-free inks in printing, the composite strength and heat-sealing properties cannot meet the requirements, so there are few applications.
Non-benzene ink generally refers to the use of polyurethane resin as the main resin ink, basically does not contain benzene solvent, even to achieve a certain printing effect, use a small amount of benzene solvent, the ink after drying the benzene solvent residue is also very small. Therefore, benzene-free ink will gradually be welcomed by dairy producers.
For milk powder packaging and printing inks, the direction of future technology development will be benzene-free inks. With the improvement of people's environmental protection and health awareness, such inks are likely to become the mainstream of printing inks in the coming years. In addition, some ink manufacturers are currently researching more environmentally friendly water-based plastic printing inks and have already entered the trial printing stage.