Boiling-resistant aqueous composite ink and preparation method thereof

Abstract

The invention discloses boiling-resistant aqueous composite ink and a preparation method thereof. The boiling-resistant aqueous composite ink mainly comprises raw materials including aqueous polyurethane resin, a pigment and water, and a surface wetting agent, a wetting dispersing agent and a defoaming agent are additionally added. The preparation method of the boiling-resistant aqueous composite ink comprises the following steps of: firstly, adding partial aqueous polyurethane resin into a stirring reaction kettle; secondly, slowly adding the surface wetting agent, the wetting dispersing agent and partial defoaming agent, and adding the pigment after stirring and dispersing; thirdly, stirring and dispersing at high speed, and grinding after dispersing; fourthly, adding the residual aqueous polyurethane resin and defoaming agent and stirring and dispersing, and adding the water until the required viscosity is obtained through regulation; and at last, stirring, dispersing, filtering and packaging. The boiling-resistant aqueous composite ink, provided by the invention, is prepared by taking the high-performance aqueous polyurethane resin as a connecting material, and has the advantages of good pigment dispersibility, wide use range, lower film forming temperature, better mechanical property of formed film, more uniform particle size distribution and the like, and can be used for soft retort packages.

Description

technical field [0001] The invention relates to a composite ink for food packaging printed matter, in particular to a retort-resistant water-based composite ink and a preparation method thereof. Background technique [0002] Since my country's ink manufacturing industry began to produce benzene-soluble composite inks with chlorinated polypropylene resin as the main binder in the early 1980s, it has developed relatively rapidly in the past 20 or 30 years, and the manufacturing and printing processes of inks are all different. has matured. However, from the analysis of the development trend of gravure composite ink, benzene-soluble composite ink has the following shortcomings that are difficult to overcome in the production and use: (1) A large amount of aromatic hydrocarbon solvents are used: because the main binder polyurethane resin of the ink is used in the synthesis process. Toluene, and it also needs to be dissolved with toluene; so the main resin of the existing benzene...

AI Technical Summary

Problems solved by technology

However, from the analysis of the development trend of gravure composite ink, benzene-soluble composite ink has the following shortcomings that are difficult to overcome in the production and use: (1) A large amount of aromatic hydrocarbon solvents are used: because the main binder polyurethane resin of the ink is used in the synthesis process. Toluene, and it also needs to be dissolved with toluene; so the main resin of the existing benzene-soluble composite ink is toluene as a true solvent, and it is inevitable to use a large amount of toluene in the production and use of the ink, because the release of toluene by the resin The toxicity of toluene is very high, and it is very easy to cause the residual solvent of the printed product to be too large in the flexible food packaging, thereby contaminating the food and having a great impact on the quality and safety of the food; (2) The scope of application is narrow: in the plastic composite flexible packaging industry Among them, the most commonly used outer printing films are BOPP, PET and BOPA, while the benzene-soluble composite ink is only suitable for printing and laminating BOPP, and it fails to provide excellent adhesion and composite strength for PET and BOPA, and even Can not be used for packaging of frozen, oily, boiling, cooking and other foods; (3) Poor thermal stability: Due to the poor thermal stability of chlorinated polypropylene resin, chlorine is easily released during the production and storage of ink to form hydrogen chloride, which makes the ink into strong acidity, thus affecting the storage stability and printing use of the ink

Although alcohol-soluble inks can effectively solve the problems of toluene solvent residues on health and the impact of solvent residues on the quality of packaged food, and have been widely used in the domestic gravure printing industry, gravure alcohol-soluble plastic inks still have solvent odors

Water-based gravure inks have attracted a lot of attention as an alternative to solvent-based inks, but water-based inks in packaging film printing have not been widely used until now

[0006] At present, the water-based composite ink produced by a small number of ink factories is only white ink, which is prepared from water-based acrylic emulsion as a binder. It has poor dispersion of pigments, low gloss, poor printing effect, low screen transfer rate, and the ink cannot be used. for cooking