LED exposure units are the new standard for any screen printer’s darkroom. But why? Many factors make LED light optimal: light output, speed, consistency, and more. Here are three benefits of using LED exposure bulbs in any darkroom.
SPECTRUM OF LIGHT OUTPUT
One benefit of choosing LED exposure is the ability to optimize the spectrum of light output. Exposure time and correct curing of emulsion are both heavily dependent on using light of the correct wavelengths. This light must be able to both penetrate the coating, as well as promote cross-linking.
The ability of light to penetrate and crosslink the emulsion is directly related to its wavelength. Also, how the light is able to react with the diazo, or photopolymer, that is used to ‘sensitize’ the emulsion.
RELATED: EXPOSURE UNITS DESIGNED TO PERFORM
UV light is too strongly absorbed to penetrate thicker coatings. In this case, longer wavelength violet/blue light is needed. This light, around 405 nm (nanometers), is better able to penetrate and crosslink the emulsion. It can not only cure the emulsion surface but can cure deeper layers to effectively crosslink the emulsion that is in contact with the mesh. Encapsulating the mesh threads this way guarantees robust screens that are able to withstand the rigors of printing and cleaning on press.
Using 405nm LED also gains printers the benefit of wider exposure latitude. During exposure, all sides of the emulsion layer are cured simultaneously.
LED bulbs last way longer than halogen bulbs, which saves printers money. Replacing the bulbs less equals instant savings. LED bulbs are also better for the environment since 95% of their energy is used for light, and only 5% is wasted, according to Solar Electric Power Company.
First, the LED bulbs in Baselayr exposure units are explicitly designed for exposing screens. Again, the bulbs produce an optimal UV wavelength (which works for both dual cure and photopolymer emulsions). Having optimal UV wavelengths means screens expose faster and produce better detail. Printers can replicate the same quality burns from a great exposure platform, each and every time.
Upgrading to LED exposure benefits printers in many ways, and helps the environment out too. Better, quicker exposure at a fraction of the cost should be a no-brainer.