Good adhesion to glass has always been difficult to achieve. As a result, graphics for glass applications had to be printed first on a clear, flexible substrate and, then, applied to the glass. That meant extra steps, possible installation issues, and the risk of wear and tear to the applied substrate over time.
EFI developed a process to print an image direct to glass, eliminating the need for extra substrates, and application printing and installation time. Accomplished by using EFI Glass Cleaner and Primer, the process works when using any EFI VUTEk hybrid printer.
While glass appears to be clear, there is actually one side that will appear foggy when viewed with a short wave UV light. Take your sheets of glass into a dark room. Hold the short wave UV light close to the sheet of glass and determine the foggy and non-foggy sides. You will print on the non-foggy side of the glass.
Spray a liberal amount of EFI Glass primer on the cleaned sheet of glass. DO NOT use the same wipes you used to clean the sheet. Take a new clean wipe and spread the primer evenly onto the entire surface of the sheet. Continue until the primer appears to be dry.
With your cotton gloves still on, move the cleaned and primed glass sheet to the printer. Print the image/graphic onto the glass.
Using high temperature, heat-resistant gloves to remove glass from the conveyer belt and set aside to cool for approximately 30 minutes. Be sure to place them somewhere where no one will accidentally touch them, as the glass will be very hot.
At this point, the process is complete. The heat bonds both the primer to the glass and the ink to the primer. You now have a finished graphic printed direct to glass and ready to ship out to your customer.