Screen printing heavily revolves around preparing screens for the actual printing press to be used in printing. Coating, burning, and reclaiming screens are a larger part of the printing process and should be done away from the main production space. A darkroom, sometimes referred to as a screen room, is just as important of a space as the actual production space. A well organized darkroom with the right equipment, tools, and layout allows employees to prepare and reclaim screens at a faster pace.
It is extremely important that a darkroom not have any UV light entering the room or even normal fluorescent lights as they will pre-expose a screen, which will render it useless. Humidity must also be controlled and kept very low as coated screens will hold moisture if it is in the air, which will cause problems when it comes time to burn the screen.
When it comes to organizing a darkroom it all starts with the main equipment that will be used in the room, which is an exposure unit and screen drying cabinet. Exposure units and screen drying cabinets are typically located directly next to one another. However, it is not a necessity that they are as a screen never goes directly from one piece of equipment to another. Both pieces of equipment use a decent amount of electricity which means they sometimes can’t be used at the same time if they are plugged into the same electrical outlet/breaker.
Another piece of equipment that is often used in a darkroom, but not always, is an alignment tool for registering screens. A screen registration/alignment tool should be located directly next to the exposure unit as the process goes directly from screen registration to being burned using an exposure unit.
Outside of burning coated screens the darkroom is also where screens themselves are coated. Coating a screen requires a very small amount of space, and a simple stand that holds a screen in place is all you need. Because a screen must be dried right after it has been coated with emulsion the screen coating stand should be located right next to the screen dryer.
The majority of the space in a darkroom is used to store coated or clean screens waiting to be coated. Screen racks that hold around 25 screens can be purchased for around $300 from must supply businesses, but you can easily build the same thing with just a nail gun and less than $100 worth of materials (2×4 and 1×2 lumber).
A washout room is a room that is located directly next to a darkroom and is where screen are reclaimed and washed out after being burned. This room must have running water. Running water creates humidity and it is important to not let that humidity make its way into the darkroom. A washout room must contain an industrial washout sink, electric power washer. Also. if it’s in the budget, then an air compressor and dip tank should also be located in the room. A washout room must have plenty of light in it to make sure screens are completely cleaned during the reclaim process and after a screen has been burned and needs to be washed out.