Screen printing

Lab has two Mekanika screen printing sets for max. A3-sized prints on textile, paper, cardboard and thin sheets of wood, metal, acryllic etc. We hold several colors of textile paint and puff paste.

How does it work?

Silkscreening or screen printing is a printing technique where a mesh screen is used to transfer ink onto a substrate such as paper or textile, except in areas that are made impermeable to the ink by a blocking stencil. Ink is then applied to the screen and moved across it with a squeegee to fill the open mesh apertures with ink. A reverse stroke causes the screen to touch the substrate momentarily along a line of contact and causes the ink to wet the substrate and be pulled out of the mesh. One colour is printed at a time, so several screens should be used to produce a multi-colored image. Screens have different mesh sizes which will determine the amount of ink that is applied to the substrate; textile typically needs more ink to fill the fibres than paper does.

Making a stencil / preparing your screen

You can make a stencil in a couple of ways. The quickest and most straightforward is by simply cutting or tearing or lasercutting shapes from paper or lasercutting polypropylene stencils and placing them under the screen in order to "block" the ink from passing to your material.

Another way is the photo emulsion technique. Photo emulsion is a thick liquid substance which you apply to your screen. Photo emulsion becomes solid when exposed to light, making it more difficult to remove. You create your stencil by firstly drawing or printing the image you want to screen print on a transparent sheet (one for each color needed) and placing it under the screen on the lighting table. After exposing the screen to light, you wash away the emulsion that has not been exposed, so the ink can pass through. A screen treated in this way, can be used to make a large amount of prints.

Printing on transparents

It is important that you have or create an image that consists purely of black and white, so no grayscale. This is important since the "holes" of a screen can only be open or closed, there is nothing in between. If you have a grayscale image, you must first convert it to a bitmap (see the image below), to create the illusion of grayscale.

~ more to come!