I. Ink painting system and application
Water-based ink referred to as "ink", is water as a solvent, water to replace the traditional solvent based ink accounted for 30%~70% of the organic solvent. With water-based emulsion as binder, adding nanometer color paste, water-based additives after certain conditions of composite, from the raw materials, generally divided into three kinds: water-based acrylic ink and water-based polyurethane ink and hybrid resin water-based ink, the three kinds of ink in the market application is also different.
Water-based acrylic ink is mostly used in ordinary printing, such as supermarket shopping bags, health supplies, industrial packaging bags and other surface printing. There are also part of the food soft packaging, but mostly light packaging. For some special functional requirements of packaging, acrylic ink has certain limitations, but it has the advantage of cost.
And waterborne polyurethane type ink is widely used, especially in food soft packaging, its application stability, advantages far better than acrylic type ink, especially in some functional packaging application.
Two, the environmental protection of water ink
The production and application of all water ink painting do not add toxic organic solvent, fundamentally eliminate the volatilization of harmful gases, is a real green environmental protection material. The all-water ink fully conforms to the new standard hJ371-2018 issued by the Ministry of Environmental Protection and the requirements of VOCs content ≤5% for gravure and flexo printing ink itself. In the process of application, no alcohol thinner is added, and the so-called environmental protection ink with alcohol solvent instead of other solvents is not a true ink. The ink composition containing a large proportion of alcohols or esters of cosolvent, in application of printing process will add a lot of alcohol, the so-called green ink in the market even fire can burn, may be a transitional product, the product of VOCs processing also has certain difficulty, the vitality of products need to market recognition. (If this kind of product is tested by VOCs detector, the VOCs content in the ink is far more than 2000mg/m³)
At present, there are two ways to solve the VOCs waste gas pollution in the printing industry: one is the source management, the other is the end management. The use of ink printing is the best way to source governance, green environmental protection, energy saving and money saving, the end of the governance of all the problems. During the current epidemic period, the country has relaxed to develop the economy, protect enterprises and environmental protection. Therefore, during this period is the best time for enterprises to reform and adjust themselves. Business owners should seize the moment, but there are few adopters.
I think the root of all problems lies in the cognition and thinking of ink painting. If you want to completely solve the problem of VOCs emissions, you should first change your thinking, reflect on the pain, and make up your mind.
Three, good water-based ink should have the performance
Good water-based ink should have the following points:
1, high color concentration, high solid content, stable viscosity;
2, bright colors, strong color display, L, A, B value to be stable, easy to color printing factory color management;
3, ink printing suitability is strong, fatigue resistance is good, long time printing do not appear knife line and other problems;
4, leveling, adhesion, water resistance, fast drying, transfer to be good;
5, OPP, PET, NY integration, simple to use, easy to manage and application;
6, add water to print, don't let the printing house spend money to buy alcohol;
7, the comprehensive cost is lower than solvent ink, which is conducive to the cost control of printing plants;
8, the printed matter should be able to meet customer requirements, especially the light transfer problem of shallow network (highlight and dark reflection).