More about Screen-printing
Earlier this year I said that I would share more information with you about other types of screen-printing technique.
Exposed screen-printing method
If you are lucky to live near a print studio (there are many of them up and down the country) and you want to learn more, they are well worth joining. You need to check that they have a screen-printing exposure unit, preferably with a vacuum.
With this method you start with a clean dry screen. The screen is then coated in a light sensitive paint and left in a dark room to dry/cure. You then need to draw your design onto a clear acetate sheet, making sure that the black lines are well defined. Once the paint is dry you place the screen in the exposure unit on top of the image you want to have on the screen.
The black areas of your image will stop the light affecting the paint so that, after exposure, you wash the screen and the paint washes out of the areas where the black lines were. You then allow the screen to dry again and tape up the edges. Using parcel tape, make sure that there is a strip of tape all around the inside edge of the screen to stop paint from collecting there and in turn to stop it from coming through the other side, which could damage your prints. You are now ready to start printing. Here you can use the image to print on paper or cloth and this image will last for a very long time, allowing you to make many, many prints.
Just as with the paper stencil method of registration you will need to set up your screen so that you know exactly where your print will land.
Put your screen in the clamps, place a sheet of acetate under the screen and tape it on one side. Next pull through a layer of ink so that you can see exactly where the image will be produced. Use this layer on the acetate to register with the paper you want to print on. Remembering to flip the acetate out of the way before printing.
Using the registration methods as described above, you will be able to line up your work in exactly the same place every time. If you expose more than one screen so that you can have multiple colours on your finished print, using this registration method will make life much easier for you.
It is important that every time you pull through a layer of ink, you flood the screen (which is gently returning the squeegee, from the pull, to the top of the screen pulling back the ink from the first print.). If you don’t, the ink will dry on the screen and you will not be able to produce any prints until you have cleaned it and started again.
Hand painting method
There is also a fun way to make monoprints using a screen. Tape up the edges of a clean dry screen as before. Produce a design you want to work with and transfer it onto an acetate. Then put a block under the screen so that it isn’t touching the acetate but not so high that you can’t see the image on the acetate sheet.
Now get your brushes out and paint the image onto the screen. You will need to work quickly so that the screen doesn’t dry out and you will need to paint the areas you don’t want the ink to transfer onto with print medium. The fun thing about this method is that once the first layer is dry, you can add more and more layers giving a rich finish to your screen monoprint. You can also use a mixture of hand painted screen-printing along with paper stencil screen-printing (see January 2020 blog for full details) and light box exposed screen to produce your unique prints.
There are a number of different inks/paints which can be used for this process. I use System 3 as I can use it in other painting projects, such as the fibreglass animals and hearts I have decorated, giving me a lot of product flexibility. System 3 produces a print medium which increases the translucency of the paint which is particularly useful if you want to produce glaze type effects in your prints. If you are looking to do this it is important to use yellow first, then oranges, reds, greens, blues and finally black.
The beauty of using System 3 is that you can, if you prefer, use opaque colours like white over the top of any of the print if that is a look you are going for. When using print medium, do not use a ratio of more than 50:50 as the paint can suffer and always place the medium in a cup first and add the paint to it.
Mix up a good amount of paint for your print project as, though not much is really used, you need to apply a good amount to the screen to pull the print for it to be successful.
You won’t waste the paint. I use old glass jars, well cleaned of course, to store my unused paint. It lasts for ages, easily a year as long as the cap is secure so that the air doesn’t get to it.
You can also buy fabric medium and some printmakers I know only use fabric medium as you can use it on both cloth and paper. If you want to print on fabric you will need to either iron it on the reverse side when it is dry or use a heat gun to dry it from the front so that it won’t wash off.
You may lose a little colour on the first wash if you are printing T-shirts but the heat from the iron will fix it in place if you have done it for long enough. You will also see that when you pull the fabric underneath the print, the ink will move but not crack if you have fixed or cured it properly with the heat.