Screen Printing has been a popular technique for printing onto T-Shirts, Bags, Hoodies and all sorts of clothing and materials for years. In fact it first appeared in recognizable form in china during the Song Dynasty 960-1279 AD!
Traditionally screen printing was done using silk screens although now most screens are made using synthetic threads such as nylon which is stretched in varying density between wooden or aluminium frames and tensioned.
To create a stencil the screens are coated in a light sensitive emulsion and allowed to dry before being exposed to a high intensity light whilst covered in an acetate bearing a blackout print of your design. The black ink prevents the photosensitive emulsion on the screen from curing where your design is and the rest of the screen cures to an impermeable stencil. Once the exposure is complete the screen is then washed to remove the uncured emulsion which leaves a perfect stencil of your design. A separate screen is required for each colour in the design and once all the screens have been cured and washed they are loaded into a screen printing carousel.
Once in the carousel the screens are aligned so that when the ink is transferred to the garment the images combine to create your complete design. This is done using machining on the carousel called micro-registration that allows for each element of the design to be accurately aligned with the rest.
With all screens aligned with each other and in the correct place on the T-shirt the ink is then mixed to the required colour using a Pantone matching system and loaded onto the screens. To transfer the ink to the t-shirt the screens are pulled down until they are sitting just above the garment and a squeegee is pulled across the screen releasing ink through the open areas of the stencil and onto the shirt. This is repeated until all colours of the design have been printed.
Finally the T-shirts must be cured to ensure that the ink has bonded with the garment properly. Typically Plastisol inks need to reach a temperature of around 150-160 degrees Celsius in order for the chemical structure of the ink to change and bond securely to the garment.
So now you know! There’s a bit more to the process of taking a design from your desktop to a t-shirt but we love it and as long as you keep coming up with amazing designs, we’ll keep printing them for you.
If you do have any other questions about the process of screen printing or are interested in the techniques we use just ask and one of our team will be more than happy to help you out.