ETEC and its DLP process

Digital Light Processing (DLP) is one of the main 3D printing technologies available today. It is a photopolymerization process, which essentially consists of using a video projector to polymerize photosensitive resins. This technology is popular for both its speed and accuracy and can be used in a large number of industries. And she just keeps getting better.

The first company to commercialize the technology, EnvisionTEC, has come a long way over the years. And since its acquisition last year by Desktop Metal, which split the company into Desktop Health and ETEC, it has showcased its most exciting innovations in the field, including top-down DLP, new materials development such as rubber, etc. But how does DLP work? What exactly are the innovations brought by ETEC in this sector? And above all, what are the applications of this technology?


The tray of the ETEC DLP Extreme 8K 3D printer (photo credits: ETEC)

How it works ?

Light-curing, or the curing of photoresists via UV light, can be considered the parent of additive manufacturing. As you may know, the very first 3D printing technology was stereolithography, invented in the 80s. However, soon after, new technologies began to appear to solve the inherent problems of ALS. These include the DLP which came into being in 1999.

Thanks to the use of a DLP chip, the digital light processing made it possible to use light from a projector to polymerize photoresists for large-scale 3D printing. The technology is faster than SLA because it allows the entire build plate to be exposed to UV light instead of a single point cure like with a laser, while allowing for a high quality surface finish and defined edges. This has made it a benchmark among vat polymerization methods.

A traditional DLP machine operates from the bottom up, with a projector located below the tank. This process was used with the very first commercial DLP printer, the EnvisionTEC Perfactory. Thanks to its location on the underside, the light from the projector can be transmitted through the bottom of the tray into the resin, allowing quick and tight layer height control. The build plate is designed with a transparent bottom allowing light transmission and then, as with other resin technologies, the print bed moves up and down the z axis in the resin vat, creating a thin layer which can be hardened.

DLP process

The traditional DLP process, originally marketed by EnvisionTEC (photo credits: Wevolver)

Since this first printer, many advances have been made in the field. In 2015, the CLIP process, which included a layer of oxygen delivered by an oxygen-permeable film, eliminated the need to separate each cured layer, dramatically increasing speed. The application of this “dead zone” was pioneered by EnvisionTEC in 2016 in a new process called CDLM, or continuous digital light manufacturing.

In 2021, after Desktop Metal acquired EnvisionTEC, another new technology was released, Hyperprint, which eliminates the need for oxygen layers. According to Desktop Metal, Hyperprint uses heat to decrease the viscosity of resins and speed up printing. It also includes closed-loop printing, with CLP sensors, to detect when the part layer has completely separated from the resin vat film.

The company’s latest breakthrough was in the area of ​​top-down DLP. Although bottom-up DLP has been the norm for the past 20 years, ETEC launched the Xtreme 8K top-down DLP printer to address a number of limitations. This all-new machine has a number of benefits for users, including an expanded material portfolio for even more applications, and represents the latest in DLP technology.

What are the advantages of the ETEC Xtreme 8K DLP printer?

Users can expect a number of benefits when using ETEC’s DLP Xtreme 8K 3D printer beyond the general advantages of DLP technology such as speed and complex geometries. For example, previously using bottom-up DLP, users faced restrictions on the number of parts that could be printed, as there was a limit on the weight that could be supported vertically from the build plate. printing and a need for a large quantity of supports to ensure adhesion. In addition, the types of resins that could be used were subject to serious constraints, since coating required low-viscosity resins. This therefore limited the throughput and properties of the final material.

The DLP Xtreme 8K printer is able to overcome these obstacles, offering the largest DLP print area (450 x 371 x 399 mm – 166,950 mm2) among commercial production DLP printers, thanks to top-down DLP “. It is capable of printing large parts or high volumes with new materials that Desktop Metal says can directly compete with thermosets used in traditional plastic injection molding.

Zoom on the DLP Xtreme 8K 3D printer (photo credits: ETEC)

These advances in materials have been made possible in particular thanks to the research and development work of Deskop Metal through its subsidiary Adaptive 3D. This company succeeded in creating a new family of materials, DuraChain photopolymers. They are single-component photopolymers, having undergone one-pot synthesis, and which use phase separation induced by photopolymerization, or Photo PIPS. Examples are foams and rubber materials. This feature, among others, has opened printers using DLP technology to many new applications in a variety of industries.

DLP is used to revolutionize rubber parts

One of the most interesting applications of ETEC’s top-down DLP is in the manufacture of rubber parts. Aerosport Additive, an Ohio-based service bureau that produces prototypes and working models for customers in industries such as automotive, aerospace, electronics and more, discovered that the ETEC’s DLP technology and the DLP Xtreme 8K printer were key to creating better rubber parts.

Prior to adopting DLP technology, Aerosport Additive had to use urethane molding for prototyping and small-batch production, and injection molding for mass production of rubber parts. Indeed, creating rubber parts has always been a challenge for additive manufacturing, as it was almost impossible to create materials with the look, feel and performance of real rubber. Today, this is no longer the case.

Thanks to the Xtreme 8K top-down DLP 3D printer and new materials, Additive Aerosport is able to produce rubber parts (photo credits: ETEC)

Using Adaptive3D’s Xtreme 8K and Elastic ToughRubber, the company was able to quickly and cost-effectively produce rubber parts with Shore A70 hardness. For example, she created four-position switches that are attached to aircraft control sticks, essential for making precise adjustments to the aircraft’s trim controls.

As you can imagine, these parts are usually made in small batches, but switching to urethane casting was a slow and expensive process. With the ETEC Xtreme 8K, Aerospace Additive can now produce up to 150 switches in a single 2.5 hour build, saving time and reducing costs. Additive manufacturing further provides the ability to modify or refine the design to meet the needs of different customers. This application, among others, shows how ETEC’s DLP processes could continue to impact even more industries in the years to come. To learn more about ETEC and its DLP solutions, click HERE.

What do you think of ETEC’s technology? Share your opinion in the comments of the article. Find all our videos on our channel Youtube or follow us on Facebook Where Twitter !

Leave a Comment