From screen printing to digital printing to frit printing, there are several techniques used at Boyd to print on glass.
To ensure the success of any glass-printing application, there are numerous factors that go under consideration such as glass type, inherent tint of the glass, ink type, ink color, curing process, and environmental conditions. However, one crucial factor that needs to be determined is the print method. Glass can be printed on using one of the three techniques: screen printing, digital printing, or frit printing. While all these methods support different shapes, sizes, thicknesses, types of glasses, and allow the use of multiple colors, there are unique pros and cons that distinguish them.
Screen Printing on Glass
Well-suited for a wide range of applications, screen printing is the most cost-effective and predominantly used glass printing technique. It primarily utilizes two types of inks: enamel inks and UV-cured inks, both with good opacity. UV-cured inks offer a larger color selection than enamel inks. Since each color requires a separate screen, the process can be time-consuming if the design has multiple colors involved. In most cases, the graphic features are printed on the rear side of the glass, which is typically sealed or bonded with a touchscreen or display. Except for the edges of the glass, the ink is almost never directly exposed to ambient conditions and corrosion. However, if the ink is not specially formulated for printing on glass, it can lose adhesion and begin to chip quickly.
Digital Printing on Glass
Digital printing on glass functions like a regular inkjet printer, where the only requirement is digital art file to print. It affords greater flexibility in terms of changing designs at the last minute. Unlike screen printing, where any design variation requires the construction of a new screen, modifying an art file for digital printing is quick and easy. This makes it a great choice for prototyping and achieving faster time-to-market products. But it is important to note that the inks utilized for glass digital printing are thinner compared to the inks employed in screen printing. Hence, while working with light or pastel shades, multiple layers may be required to achieve a sufficient level of opacity. This can lead to an increased thickness and can pose challenges in the optical bonding process. In contrast to screen printing, where one color is printed at a time, digital printing also allows the printing of all the different colors at once. Digital printing on glass is currently undergoing continuous developments to accommodate more types of inks.
Frit Printing on Glass
Frit printing is similar to screen printing with the exception of the ink utilized and the curing process. A unique powdered-glass ink is screen printed onto the glass and cured during the heat tempering process. The heat fuses the ink to the glass, offering strong adhesion and making it difficult to remove or scratch the ink off. Since frit printing offers the highest durability out of all the techniques, it's ideal for applications where the glass is regularly exposed to challenging environmental conditions commonly found in the defense, industrial, and eMobility sectors. However, it is also the most expensive printing method and therefore, not as frequently employed. While frit printing can be done on heat-tempered glass, it generally cannot be utilized for chemically-strengthened glass, as the glass thickness has to be greater than 2mm for the frit printing process. Frit colors are also limited to black, white, and some grays.
Bringing together the right mix of functionality and durability for your custom application, the experts at Boyd can not only help you select the most suitable printing technique for your glass application, but also support your glass printing and bonding needs from prototyping through production. To learn more about Boyd's bonding solutions, schedule a consultation with our experts.