Know Your Materials: Urethane Methacrylate (UMA)

Originally published on fastradius.com on February 11, 2020

Capable of producing highly detailed prints, Carbon® Resin Urethane Methacrylate (UMA 90) is often an excellent choice for mechanical manufacturers.

UMA 90, the proprietary urethane methacrylate resin produced by Carbon, is a single cure resin designed for prototyping and producing mechanical parts, enabling manufacturers to lean into 3D printing. Printing with this resin is fast, easy, and yields high-quality products. Here’s everything you need to know about Carbon Resin UMA 90.

Mechanical Specifications

Urethane methacrylate is a photosensitive polymer liquid resin similar in mechanical properties to selective laser sintering plastics. Once cured under UV light, UMA 90 becomes rigid, abrasion-resistant, and able to withstand the wear-and-tear of repetitive movements. For this reason, urethane methacrylate is ideal for making jigs and fixtures.

The structural integrity of UMA 90 can be largely attributed to Carbon’s Digital Light Synthesis (DLS)™ process. A photochemical procedure, DLS uses digital light projection, oxygen, and a liquid resin of choice (like UMA 90) to print high-fidelity parts. A 3D printer steadily projects a series of UV images through an oxygen-permeable window into a bath of curable resin. The parts then solidify and the build platform rises. DLS-printed parts are more akin to injection-molded parts than traditionally printed parts, and feature solid interiors and smooth, well-finished exteriors.

UMA 90’s key mechanical specifications include:

• Tensile Modulus: 2000 ± 100MPa
• Ultimate Tensile Strength: 46 ± 3MPa
• Elongation at break: 17 ± 2%
• Flexural Modulus: 2010 ± 119MPa
• Hardness: 86, ShoreD
• Density, ASTM D792: 1.200g/cm3
• Heat-deflection Temperature 0.455 MPa/66 psi: 51°C
• Notched Izod (Machined), ASTM D256: 33 ± 4J/m

All of these specifications apply to UMA 90 in its UV-cured state. For more information about this resin’s properties in its green state, refer to the material’s technical datasheet.

Why UMA 90?

UMA 90 stands out from other general purpose resins for its versatility, and reliability. This resin has all of the mechanical properties of traditional plastics like Nylon PA12, with added durability. In contrast to similar materials like prototyping acrylate (which have moderate strength), UMA 90 is built for the long haul. Manufacturers can count on a fast, strong, high-quality print that’s able to withstand daily use in heavy machinery.

An additional advantage of urethane methacrylate is that it enables the production of completely smooth parts, rather than requiring a subsequent polishing process. The result is elegant, ready-to-use parts and reduced production costs. UMA 90 is also one of the few Carbon resins that takes well to overmolding, so users can print with various kinds of resins and create custom colored prints.

UMA 90 is also an option for use in medical devices. Rigorous biocompatibility testing has proven UMA 90 safe for prolonged skin contact and up to 24 hours of mucosal-membrane contact. It has also met International Organization for Standardization (ISO) standards ISO 10993-5 and ISO 10993-10 for use in medical devices.

Follow these biocompatibility best practices to use UMA 90 safely:

• Remove the build platform from the printer using tweezers, blades, or scrapers.
• Wear protective gloves and eyewear at all times.
• Wash all parts in Vertrel XM™ for three to five minutes, making sure to agitate the mixture.

For more information on safety, refer to the Carbon Resin UMA 90 biocompatibility requirements datasheet. Multi-purpose polyurethane (MPU) is another great option for parts that will be used in medical devices.

Popular applications

Medical device manufacturers who integrate UMA 90 into their production processes will be able to efficiently produce non-toxic, durable, smooth, high-integrity 3D-printed medical devices at scale, positioning themselves to outperform the competition. From drug-infused stents to casts, the possibilities are endless.

Beyond medical applications, UMA 90 can be used in applications across a variety of industries. With the power to produce clean, smooth, and colorful prints that are durable enough to withstand repetitive and intensive testing, UMA 90 is ideal for the production of a range of parts. What’s more, users can count on UMA 90 to produce a consistent result time and time again — no more “bad batches.”

Getting started with UMA 90

UMA 90 is among the best choices for prototyping and manufacturing mechanical parts thanks to its balance of strength, efficiency, and versatility. UMA 90 yields parts that are biocompatible, durable, and smooth before curing — an attractive option for manufacturers in a variety of sectors.

If you’re ready to start producing viable parts made with reliable materials and get products to market faster, contact the SyBridge team today. Thanks to recent advances in hardware technologies, savvy companies have endless opportunities to optimize their operations with additive manufacturing. Let’s work together to bring your vision to life.