How it is made: what are the main inks used in screen printing?
Plastisol inks
The Plastisol is an ink that comes from plastic and is the one most commonly used in the printing of T-shirts in screen printing : it is a homogeneous liquid mixture ready for use which works very well in the case of images with gradients, shadows and halftones. The beauty of Plastisol is given above all by the accuracy of the colors and their covering consistency: in fact, thanks to the Pantone Color Matching System® , it is also possible to recreate and print Pantone colors. Plastisol contains resins and plasticizers and therefore requires very high temperatures for the polymer to dissolve in the plasticizer and dry properly.
Plastisol is easily printable even with high thread count frames and offers colorsparticularly bright . Furthermore, unlike waterbase inks, it provides a wide range of special products and applications. However, since Plastisol is composed of resins and PVC (a suspension of polyvinyl chloride in plasticizer), it is rubbery to the touch and therefore is not suitable if you want to make a vintage hand print and / or an eco-sustainable collection. Although there are techniques for lowering the viscosity of the material, the result will be difficult to compare with that of a print made with the dtg technique ( direct-to-garment or direct digital).
Water based inks
Water-based screen printing inks typically consist of two components: the aqueous base and the pigments, which are added to the base to create colors. These inks are well suited for printing on white and light fabrics and can also be used if silk-screen frames are used on natural fabrics and paper. In the field of screen printing, water-based ink is an excellent alternative to Plastisol, as it has some interesting advantages.
It is equally resistant to light and washing, although it does not pass through the oven, and is therefore perfect for synthetic fabrics such as polyesterand acrylics, which cannot be subjected to high temperatures; moreover, it allows to obtain a vintage and soft hand, because the ink filters into the fabric and leaves only a thin layer on the surface. Since waterbase inks are free of plastic and PVC, they are also eco-friendly and easy to use. One of the main disadvantages of this type of ink is given by the fact that the printing results with water-based inks on dark fabrics are of a lower quality than those obtainable with Plastisol. In addition, waterbase inks are much more expensive, as well as difficult to manage, and Pantone colors, mid tones and shades are more complex to obtain.