Screen-printing has withstood the test of times and still very popular in the digital age. The printing process is simple yet able to produce marvellous prints that match or even better than the output of digital prints. It is one of the reasons for the popularity of custom screen printing that holds a monopoly in T-shirt printing despite many other fabric printing methods available.
The screen-printing method is simple in that it uses a polyester fabric or fine mesh screen tightly stretched across a strong wooden frame or platen that forms the print media. The design is cut out on a stencil and fixed on the screen, which is held against the surface to be printed. The ink placed on the screen is then rubbed with a rubber squeegee to force the ink through the screen that passes on to the material to be printed and sticks to it.
For multi-colour print, it would require several stencils depending on the number of colours with each stencil meant for one colour only. On completing the process of printing for all colours, the final print effect becomes visible. To leave blank spaces in the design, the norm is to use a non-permeable substance on the screen to prevent ink from passing into that area.
To improve the print quality, you must follow the tips discussed here.
The screen is critical in determining the quality of the print by controlling the ink transfer rate to the print surface. To ensure smooth and uniform ink transfer, the screen or mesh must be tight and taut, so that produces superior print quality. A tighter mesh ensures proper registration or correct placement of the design that prevents the chances of colour bleeding if one colour tends to overlap another colour. Tight screens help to push the ink easily with less labour and even help to cut the ink cleanly.
Tight screens ensure uniform deposition of ink on the substrate. If the screen is not tight, it could lead to the deposition of ink toward the edges, thereby driving more ink to the central areas and creating an unevenness that affects the print quality.
The quality of print depends on the consistency level of the ink. It can either be stiff or loose, depending on the density. Some printers try to maintain ink consistency by adjusting the pressure and angle of the squeegee when rubbing it against the screen. This process is not much reliable because it depends on the skill of the printer who drives the squeegee manually. To maintain consistency of ink, you must add an extender base and curable reducer to the ink, with the former helping to adjust the pigmentation in ink. The extender base makes the ink creamier and easier to use.
The blade of the squeegee must be straight and sharp. The sharpness of the blade ensures that the ink spreads evenly.
Holding the platen or frame firmly is equally essential to obtain high-quality print as much important it is to allow enough time for drying or curing that contributes to the print quality.