Printing is a process for mass reproducing text and images using a master form or template. The earliest form of printing dates back to 220AD where woodblocks were used to print on cloth. In today’s world, it is difficult for us to imagine a world without printed matter. The evolution of printing technologies has provided us with the possibilities of printing on materials that we never knew we could print on.

With the manufacturing of different and unique materials, along with the exponential growth of technology, we have discovered multiple ways to print on all these different materials; Glass being one of them. Glass printing is a process to convert a standard Glass into a work of art; the capability to replicate any digital image onto glass permanently. However, unlike paper and fabric, Glass surface does not absorb inks in the same way.

The Traditional Ways
Many times, we overlook the process of printing on Glass. Glass printing is done dominantly by using Screen Printing – enamel inks and UV-cured inks. Even though this process is used majorly, it is still time consuming since each and every color needs a separate screen and this delays the entire process. Another method that is used is Glass Frit Printing. It is very similar to Screen Printing method with the exception of using unique powdered-glass (frits) inks. After printing, the Glass is cured during the heat tempering process. This causes the ink to fuse onto the glass thus offering strong adhesion and scratch resistance. It offers the highest durability and therefore, is chosen for outdoor applications where the glass is regularly exposed to challenging environmental conditions. Screen printing goes through a similar glass tempering process and is an alternate to Glass Frit Printing as it can be used for indoor as well as outdoor applications.

Enter Digital Printing
With Digital Printing on the rise, we were introduced to a new process of printing on Glass. We can get very dramatic results with Digital Printing as it gives us multi-colored prints on large formats which was very difficult to achieve with screen printing as large number of screens would be required to reproduce the same output. Complex patterns can be achieved with endless possibilities. Even in Digital Printing, there are two types of techniques which can be used. The first one essentially being a flatbed digital printer designed with printheads to jet ceramic inks directly onto the glass. The technology is an adaptation of the traditional Glass Frit Printing where instead of printing using screens, we are directly using the inkjet printer. The printed glass then undergoes a similar tempering process after which it becomes a strong contender for both indoor and outdoor applications. With every new technology, comes its own challenges. The Digital Ceramic Inks are very expensive. One needs to have a furnace (or multiple) to complete the entire process. Even after tempering, there are chances of color variation due to differences in the environmental conditions of the furnace. This causes a major issue during reprint. The second technique in digital printing completely removes the requirement of Glass Frits and Ceramic Inks.

Taking the Glass Industry to greater heights with the HP Latex Platform
In 2008, HP unveiled its revolutionary Latex Printing Technology which offered a fertile foundation for the blossoming of extraordinary ideas. HP Latex inks are pigmented, water-based inks that were created with the intent of leaving the solvent world behind – an ode to sustainable development and a correct step in the right direction towards being eco-friendly. With the recently introduced 4th Generation of HP Latex Inks and Printers, we now have the ability to print on Clear as well as Non-White substrates. This is possible due to the addition of the all-new HP White Ink.

Earlier, HP’s Latex portfolio was limited to Roll-To-Roll printers and therefore Digital Glass Printing using CMYK inks was primarily being done on a UV Flatbed printer. Now, HP has very recently launched its new HP R Printer Series. These flatbed printers from HP expand the possibilities of using the eco-friendly HP Latex inks for rigid substrates as well. Unlike the UV flatbeds, the HP Latex inks do not create a thick layer on top of the substrate and preserve its original look and feel. The R Series offers high-opacity white which resists yellowing over time for applications on transparent and colored media. This is a big issue seen in the case of UV prints. The R Series combined with the latest HP Latex inks can easily print on Glass, wood, aluminum and ceramic. Moreover, it can print on mirrors, plexiglass, laminated glass, plate glass, etc. Any photo, painting or pattern can be displayed on Glass by using the HP R Series.

However, even though the Glass substrate can be printed, there comes a challenge of ink adhesion as the inks sit on the surface. The HP Latex Optimizer acts as a primer for the Latex ink to adhere to Glass surface. The ink structure for any print from an HP Latex printer is; Optimizer – Color – Overcoat. The overcoat is an anti-scratch agent protecting the print from everyday exposures. Even with this ink structure, for our Glass Printing application to work completely, we need to look out for various new and upcoming digital overcoating formulations available that help the ink to stay where they are on the surface.

Glass is an amazing print media for a variety of applications: Awards, Crafts, Tempered Glass, Mosaic, Subway Glass Tile. It can be heavily utilized in segments with short quantity requirements for printing on Glass. A huge segment to explore would be the Interior Design and Décor segment where personalization plays a very important role. In today’s world, everyone wants to represent themselves in a unique way. Today’s corporate offices and homes utilize the power of Digital Printing to the fullest and with the new addition of HP R Series Printers, it has become much simpler to achieve high levels of personalization.

But wait, there’s more!
Till now, we have read about how we can directly print on the Glass surface. However, once the design has been finalized and the surface of the Glass has been printed on, we can’t change the design anymore. Many times, in Interior Design and Décor segment, that is something that some people would not like to opt for since that would mean replacing the entire Glass whenever they decide to change the design and/or re-brand. For this, we can also print designs on a Clear Vinyl/Film and paste it on the Glass surface. The applications are endless! Many physical stores print their branding on vinyl and paste it on glass. (One-Way Vision) Corporate Offices make use of this method: Getting patterns printed on Clear Vinyl and applying it onto the Divider Walls/Partitions. These printed patterns can act as Wall Covers applied on Glass. Similarly, Glass Balustrades can be printed, doors can be decorated, and many more possibilities. The only limitation is our imagination. From minimalistic to absolutely stunning – Do it all.