Screen printing (serigraphy): technique and materials

Screen printing — also called serigraphy — is one of the oldest printing methods, but it thrives for textiles, signs, packaging and special tasks where other methods fall short.

In screen printing, a fine mesh is stretched in a frame, and the places where there should be no printing are blocked by a light-hardened emulsion — a stencil. Colour is pressed through the open meshes in the fabric with a squeegee, and only where the stencil is open does the colour penetrate through to the material underneath.

• 01The fabric type and mesh width are chosen based on the task — finer fabric gives more detail.
• 02The emulsion is exposed to light through a positive so the image 'burns' into the fabric.
• 03The squeegee technique — how the squeegee is drawn across the mesh — affects the thickness and evenness of the ink layer.

Screen printing inks differ from offset inks. Viscosity and surface tension determine how well the ink penetrates the fabric without flowing out while drying properties and durability determine whether the product can withstand washing sunlight or outdoor use. Adhesiveness is crucial when printing on demanding materials like textile plastic or metal.

Before printing starts, the stencil's quality is assessed — both by sight and with measuring equipment that can reveal weak points before they become errors in the entire print run. During printing quality is continuously monitored with appropriate equipment for objective quality control so color layer, placement, and sharpness meet requirements.

Screen printing uses both water-based and solvent-based inks as well as cleaning chemistry and all of this must be handled correctly in compliance with workplace environmental and environmental laws. It means using the right protective equipment correct storage and correct disposal of ink residue and cleaning fluid.

Screen printing requires a different touch than industrial printing methods — more manual finesse, but also the flexibility to print on almost anything, from textiles to glass and metal.