Formlabs Introduces New Polyurethane Resins!

3D printing with semi-rigid materials, such as polyurethane, has traditionally been a challenge. But this daunting task has just gotten much easier. Formlabs recently added two new polyurethane resins into its material library — the PU Rigid 650 and PU Rigid 1000 resins.

These polyurethane resins are available for Formlabs SLA 3D printers, such as the Formlabs Form 3+. They’re the toughest materials yet in the Formlabs SLA ecosystem. With these new resins, producers of polyurethane parts can embrace newfound design freedom, realise cost savings, and improve productivity.

“We’re thrilled to debut these innovative polyurethane resins as we continue to expand our materials library and unlock new possibilities with 3D printing. PU Rigid 650 Resin and PU Rigid 1000 Resin build upon the existing capabilities of Formlabs’ SLA printers to provide manufacturers, engineers, and product designers with the ability to produce polyurethane parts that can withstand extreme manufacturing environments and design requirements,” Dávid Lakatos, Formlabs chief product officer, said in a statement.

Let’s take a look at the properties and applications of these new materials. We’ll also go into more detail about the considerations of 3D printing with polyurethane.

Formlabs PU Rigid 650 Resin

The Formlabs PU Rigid 650 resin produces pliable, tough polyurethane parts. Components manufactured from this material are semi-pliable, which helps them resist breakage during bending.

Where PU Rigid 650 shines is in the manufacturing of parts that require extreme elongation and impact strength. The material gives parts 170&% elongation at break, meaning that parts produced from this material can stretch to more than one and half times their original length before breaking.

PU Rigid 650 also boasts very high impact resistance. This makes it a great option for encasing other, more vulnerable components.

Potential Applications

Thanks to high toughness and pliable characteristics, the PU Rigid 650 resin is ideally suited for producing parts that must withstand extended loads without deformation. Such components include:

• Impact-resistant casings
• Wheels
• Bumpers and shock absorbers
• Grippers and end-effectors
• Noise dampening components

As PU Rigid 650 can also withstand repeated functional use, it’s a great option for joining separate parts together with living hinges or snap fits. 

Formlabs PU Rigid 1000 Resin

The Formlabs PU Rigid 1000 resin is as unyielding as its sibling material is durable. This material creates sturdy components with high stiffness than can withstand intense impacts.

With high tensile strength, PU Rigid 1000 can handle great loads without snapping. It can support high amounts of weight for extended periods without losing its original shape or design.

Additionally, PU Rigid 1000 can also withstand other environmental stresses. It’s a material of choice for parts that must repeatedly withstand high loads.

Potential Applications

Its stiffness and strength make PU Rigid 1000 an optimal material for any loadbearing or support components. These include:

• Jigs and fixtures
• Brackets and mounts
• Safety structures and enclosures
• Bumpers
• Ducts

PU Rigid 1000 is also at home in consumer products that require frequent handling, like bike pedals, bottle caps, or belt buckles.

3D Printing with Polyurethane

Polyurethane can produce strong, tough, and durable parts. Components made from these materials are a common sight in the manufacturing, automotive, aerospace, and medical industries. But despite its great qualities, polyurethane is still an uncommon 3D printing material.

One reason for their rarity is the complex chemistry required to produce polyurethane 3D printing materials. For example, Formlabs uses a custom blend of urethane and acrylate polymers to enable SLA printers to process the new PU resins. This formulation gives polyurethane resin parts increased longevity when compared to regular, acrylate-only SLA components.

Two further causes make polyurethane 3D printing relatively obscure. Let’s examine them in more detail.

Preparing and Post-processing Polyurethane Materials

To reap the benefits of polyurethane materials, manufacturers will have to put in a bit of extra work. Polyurethane 3D printing is a more involved process when it comes to print preparation and post-processing. It also requires some additional equipment.

In order to print with either PU Rigid 650 or 1000, you must place your Formlabs SLA printer in a dry cabinet. Ambient moisture causes the resin to start curing, which can increase its viscosity to a point where printing becomes impossible.

After printing, you have to place the entire build platform in a PGDA wash and dry it either in open air or with an air compressor. Then, you must humidity cure the part. As mentioned above, moisture cures the resin, so the humidity cure will give your part a touch-safe, true polyurethane surface.

According to Formlabs, a printed part with a 2mm thickness will require three days to cure completely.

Safety Considerations

Another matter of importance with polyurethane resins is their potential health risks. Polyurethane is by nature toxic and potentially carcinogenic. You must follow proper safety precautions when 3D printing with polyurethane to protect yourself and your staff.

The heat of the SLA printing process can cause polyurethane resins to release fumes. If inhaled, these fumes can irritate the nose and throat, and high exposure could cause headaches, nausea, and dizziness.

Printer operators should always wear face masks capable of filtering volatile organic compounds (VOCs) and leave the operating area when the printer is running. You should also place the printer in a well-ventilated enclosure to minimize exposure.

Uncured polyurethane is also a skin irritant and its harmful compounds can be absorbed through the skin. Operators must wear appropriate protective gloves when handling uncured polyurethane parts.

However, as long as you follow proper safety precautions, working with polyurethane is not dangerous. Once cured, polyurethane is a safe enough material to be used in medical applications. Formlabs documentation also shows that cured parts from the PU Rigid materials are safe according to the ISO 10993-1 standard.

With these two new materials, professional SLA 3D printer operators can create tougher and more durable parts than ever before. The PU Rigid 650 and 1000 make it possible for manufacturers to elevate their prototyping and end-use part production.

— If you’d like to more about Formlabs PU Rigid 650 or 1000 polyurethane resins, the experts at SolidPrint3D are happy to answer your questions! Call us at 01926 333 777 or email us at info@solidprint3d.co.uk.