The wide application of plastic gravure printing ink

Plastic gravure inks are mainly used in food packaging, salt packaging, cosmetic daily product packaging, and pharmaceutical packaging. Food packaging is based on composite inking ink, some candy paper with table printing ink; cooking packaging using high temperature cooking ink, the general vacuum packaging is to use polyester ink; dairy packaging suitable water, acid, temperature resistant ink; Pharmaceutical packaging and cosmetic packaging are mainly based on polyester ink; some manufacturers use table printing inks, some manufacturers use composite printing inks, but more manufacturers use polyester inks; along with packaging market grades. There are more and more products that use composite inks and special special inks.

The application of water-based ink is the trend

At present, gravure printing inks used in China contain a large amount of organic solvents (about 50%). Toluene, ethyl acetate, butanone and other solvents have low boiling points, high volatility, aromatic hydrocarbons, and are toxic and flammable. They are the main sources of environmental pollution.

Intaglio printing inks are generally made of chlorinated polymers. In the ink production process, the chlorinated polymer needs to be dissolved using a strong solvent (such as toluene and other aromatic solvents), and the viscosity of the ink is adjusted with toluene during the printing process. Chlorofluorocarbon gases that are volatilized during the production of chlorinated polymer inks can destroy the atmospheric ozone layer. The use of aromatic solvents (toluene) in the printing process can harm workers' health and safety (fire hazards). In addition, the problem of ink solvent residue in packaging products is a concern. Benzene can easily remain in the dry ink film layer (low-speed printing requires the use of xylene to adjust the drying speed of the ink, xylene is more likely to remain), and benzene residues can contaminate the food or articles in the package. Although the gravure alcohol ester ink is the leader of the alcohol-soluble ink, although there is no benzene-free ketone, it will still pollute the environment and there will be residual solvent.

The production of plastic gravure inks is subject to laws and regulations such as Fire Protection Law, Labor Safety Law, Health Law, etc. Therefore, it is an inevitable trend to actively develop and apply water-based inks that meet the environmental protection requirements of green gravure inks. Water-based gravure ink as a solvent-based ink replacement system has attracted the attention of various sectors, and the ink-based water-based packaging film printing is also under development.

On the whole, the important reason why water-based gravure printing inks have not been popularized further is that the printing performance and quality still do not meet the standard for solvent-based gravure ink printing. Mainly due to the greater surface tension of water, resulting in difficult to wet the ink; water does not volatilize, printing speed can not go up.

If the printing speed and the printing quality of the gravure solvent ink are to be obtained, not only the aqueous ink itself needs advanced technology improvements, but the gravure printing apparatus and the printing plate roller also need to be improved.

For example: Change the corrugated roller or engraving roller with a depth of about 38 μm to 42 μm on the printing plate to a laser plate-making roller with a depth of about 24 μm to 28 μm. The printing roller also needs to be resistant. Corrosion materials to make. There is also a need for a more powerful, effective ink drying system, and ink squeegee and other equipment components on the press, all of which require considerable investment and long time.

Since the water-based gravure ink is removed for printing on paper, plastic film printing cannot completely replace the solvent-based ink. Therefore, the ink industry has been working hard to develop alcohol-soluble inks with less environmental pollution. Alcohol ester composite plastics gravure inks have low odor, no benzene, ketone and other characteristics. Alcohol-soluble inks can help us solve toluene-based inks, and the benzene damage and benzene residue that are caused by health affect the quality of packaged foods.