The Difference between Printing Ink and Printing Ink

Ink is an indispensable material for decoration and packaging of printed goods. Through printing, the packaging surface becomes beautiful, colorful and attractive. In recent years, with the rapid development of printing industry, packaging and printing of all kinds of plastics and paper industries have been continuously improving, and the packaging grade of products has become increasingly demanding. Compound flexible packaging printing differs from general packaging printing in that the former is lithography and the latter is printing. The ink used by the two is called lithography ink and printing ink. We must analyze the difference between the two kinds of ink before printing and use them correctly is of great significance.

Inks in China are mostly composed of 20%-40% binders, 5%-15% pigments, 40%-60% organic solvents and 0%-5% auxiliaries. The binder is a bonding resin and a link component of the ink. It binds the pigments to the printed materials, plays an adhesion role and makes the ink glossy.

Pigments determine the type of color. Solvent dissolves resin, adjusts viscosity, adjusts drying speed and improves wetting effect on printing materials. Additives can improve viscosity, weatherability, aging resistance and luster.

The following is a brief analysis of the differences between lithographic ink and printing ink, which has been summarized by our factory for many years.
1.Differentiation of Linking Materials
The binder of printing ink is mainly polyamide resin, which has good adhesion and luster, but it is not suitable under high temperature conditions, and its fastness is poor when compounded. The binder of non-cooking printing ink is mainly chlorinated polypropylene, and there are also nitric acid fibers and vinyl chloride-vinyl acetate copolymer resin abroad. Domestic Jinlong GD-1 and Dongfang 200 belong to this category. The linking material of lithographic oil quantity for high temperature cooking is polyurethane. When used, a certain amount of hardener is added, two liquids are mixed, and reaction crosslinking is carried out, such as Dongfang 300 type.
2.Differentiation of Solvents Used
The main solvents used in printing ink are xylene and isopropanol. In general, toluene and ethyl acetate are the main solvents for lithographic ink. High temperature resistant steaming inks are mainly acetone and ethyl acetate. Printing ink solvent is suitable for high-speed printing, solvent volatility is faster, solvent residue is particularly small. 
3.Differentiation of Wear Resistance
Because polyamide resin has good softness and elasticity, its wear resistance is improved by adding additives, and it runs firmly against external objects. Ink resin chlorinated polypropylene resin has excellent rigidity and poor wear resistance. Because it is lithographic printing, the requirement for wear resistance is relatively low.

4.Distinction of ingredients
Printing ink and lithographic ink because of the different links, the auxiliary materials and additives are also different, printing ink often add dehydrated apples, kiwifruit fruit esters, in order to improve adhesion, increase luster, improve viscosity. Ink printing ink also adds various additives such as pigment dispersants, enhancers, defoamers and so on.