As the human environment protection to enhance awareness of green environmental protection into the 21 st century, the development theme. In recent years, many countries already in the packaging and printing increased health, environmental protection requirements and restrictive conditions, especially for food packaging printing, because use organic solvent ink and glazing oil, will discharge hydrocarbons, pollute the air, and harmful in the developed countries, so the food packaging and printing already basically no longer use the solvent printing material. The development and application of small, less pollution, so that the pollution free printing materials become the inevitable requirement of the development of green packing, therefore, it is favorable to the environment of green packaging and printing materials will give more attention.
The composition of the water-based ink
Water-based ink is by specific water-dissolved macromolecule resins, pigments, water, and add a processed by a combination of physical and chemical process of printing ink, or ink. Water-based ink is used as a solvent, water transfer printing ink to chemical, moisture volatilizes to environment or printing, printing ink into things with the volatile and dry moisture. Water-based polymer resin is the most main water-based ink components, it mainly connections in ink painting material in the role of the pigment can equably dispersed, make the ink has certain liquidity, and provide printing and material things, make bioadhesion in printing ink can form even after the ink layer. Current research and development used more is alkali soluble resin, this kind of resin can be dissolved water, water connection, printing materials made after drying into insoluble in water of the material.
The water-soluble ink hue depends mainly on pigments, pigment particle state to evenly distributed in material, the pigment particles connected to produce light absorption, reflection refraction and transmission function, so can take on the color of certain. General requirement pigment with bright-coloured colour and lustre, suitable tinting strength and covering power, as well as the high dispersion. In addition, according to different purpose, can choose different solvent resistance of resistance. The role of the solvent is dissolved resin, make the ink has certain liquidity in the printing process, can successfully, and the transfer of ink viscosity and dry performance to adjust. Additives on ink painting influence on the performance of the big, ink painting is the indispensable and important component. Ink painting in common use additives have pH value stabilizers, slow dry agent, defoaming agent, dilute agent.
The water-soluble ink environmental safety features
Water-based ink solvent free ink, the biggest difference between the features of the dissolution of the carrier. The dissolution of the ink solvent carrier is organic solvent, such as toluene, ethyl acetate, ethanol, etc., and the dissolution of the water-based ink carrier is water and a small amount of alcohol (about 3% ~ 5%). Because water as dissolve the carrier, water-based ink to have significant environmental safety features: security, non-toxic and harmless, con not critical, almost no volatile organic produce gas. Mainly in the following four aspects:
1. The atmosphere environment pollution;
2. Reduce prints surface residue toxicology, ensuring food hygiene security;
3. Reduce resource consumption and reduce the environmental cost;
4. Improve the working environment, ensure the safety of the contact of the operator to health.
The water-soluble ink its application
Look from printing mode, water-based ink at present is not applicable, the offset of the main application fields are flexible printing, intaglio printing and nets printing.
Now the use of water-based printing ink in countries with net Sweden, Germany and the United States. Since the 1980 s, the international has developed a fabric, paper, PVC, PS, aluminum foil and metal seal of the Internet have the light and light water-based ink. Our nets printing development are quick and net printing water-based ink and the development of the popularity of the progress but slower speed. The good news is that our country in the net printing water-based ink on research and development has aroused the attention of people, after several years of effort has made some achievements. According to the report, our country in the paper and plastic printing material has been applied water-based ink screen printing.