Flexible resins are formulations in which the final polymer, after post-curing, maintains elasticity and the ability to deform elastically under load. They are the "resin" equivalent of TPU for FDM: they allow printing gaskets, covers, and soft parts with the detail of LCD printing.
When to use a flexible resin
- Gaskets and O-rings: small seals with precise geometry.
- High-definition covers: protective for devices with precise details.
- Orthodontics and dental: aligners, retainers (with ISO 10993 certified resins).
- Footwear and insoles: personalized parts with anatomical detail.
- Articulated modeling: elastic parts for joints and mechanisms.
- Hybrid prints: combined with rigid resins for multi-hardness parts.
Technical characteristics
- Wavelength: 405 nm.
- Shore A hardness: 40-90 (variable depending on the formulation).
- Elongation at break: 100-400%.
- Tensile strength: 5-15 MPa.
- Exposure time: generally higher than rigid resins.
- Post-cure: 5-10 minutes for mechanical stability.
Brands you can find on Strato3D
Flexible resins from specialized brands such as BASF Forward AM, Anycubic, Elegoo. For dental applications, please refer to our selection of medical materials.
Frequently asked questions
Flexible or FDM TPU? For small parts with fine detail: flexible. For large parts and wear: TPU.
How much does it stretch? Soft formulations reach 300-400% elongation. Rigid-flexible ones are at 50-100%.
Can they be dyed? Yes, but most already come pre-colored. For customization, use UV-stable pigments.
Is it frost resistant? Yes, it maintains flexibility even at -20 °C. For lower temperatures, check the technical data sheet.