Making The Perfect Screen

by Peter Sanders

At Prince William Pottery, we have been screen printing mugs for over 40 years. Screen printing is a tried and tested process which yields great, long lasting results for decorating mugs.

But what is the secret to creating a quality screen printed promotional mug? There are many components to creating a quality print, but one of the key components is the screen/ stencil itself. We will take a look at the components that are key to making the perfect screen.

Firstly, screen makers have to choose the correct mesh count for the print job. Mesh count is a measure of how many threads of polyester cross each other per square inch of the screen. The lower the mesh count the heavier the ink deposit that can be printed onto the mug. This is of benefit when printing on to coloured mugs, where the colour from the mug glaze can mix with the printed ink and alter the colour profile of the deposited ink. With heavier ink deposits, you can achieve a stronger colour. However, this can cause problems as the ink is more likely to spread and you can lose finer details of your printed mug design.

Conversely the higher the mesh count the less ink that is deposited on the mug, allowing for fine text and line images to be printed. But, there are limits to how fine a mesh we can use due to ceramic inks. These inks are thick in nature and if the mesh is too fine the ink cannot pass through the mesh and be deposited on the mug.

As you can see there is a balancing act to achieve when selecting the appropriate mesh count. At Prince William Pottery, we use a range of mesh counts ranging from 50T to 120T.

Once the appropriate mesh is chosen the mesh is then stretched over a screen frame. During this process, it is vital to achieve the correct tension and have consistent tension for all screens. The screen tension affects all the subsequent stages of production if this is not correct you cannot make a good screen. If screens are not of a consistent tension it makes aligning multiple colours very difficult as there is more movement in the position of the print on the mug.

The next step of the process is to use screen degreaser on the mesh. Degreasing removes any oils, dust, and dirt from the mesh, all of which can cause issues in the adhesion of your emulsion. If the emulsion does not adhere properly to the mesh there will be problems making your stencil. Once this stage has been completed the screen maker then applies emulsion film which is sensitive to light. It is then placed in a dark area and left to dry. Once the screen is dry you have a screen that is ready to have your mug design placed upon it.

When you send artwork to our artwork studio they will often request that the artwork is created in adobe illustrator and is colour separated. The reason being, is for every colour in your design a screen has to be made. We print each colour out separately on to clear film, this is what we call the positive.

The positive is then placed on the emulsified screen and put into an exposure unit, the time of exposure can vary from design to design depending on how fine the detail is of the design. Exposure time can also vary due to the strength of the UV lamps used. After exposure, high pressure water is blasted at the screen and removes the emulsion from the screen where the design is going to be printed, this allows ink to pass through the mesh where it is needed.

Now you have the perfect screen to print quality promotional mugs. Without good screens, you cannot produce high quality prints and achieve tight registration. At Prince William Pottery, we have honed the skills of screen making for over 40 years allowing us to print great value branded mugs, and can achieve close registration.

For further information or prices please contact our friendly sales team.

Categories

Leave a comment