TPU 85A – Very Soft, Highly Elastic Flexible Material

Material Profile

TPU 85A is the softest and most flexible TPU variant in the portfolio. The material is suited anywhere maximum elasticity is needed: soft seals, shock-absorbing buffers, non-slip pads or flexible sleeves.

The Shore A hardness of 85 sits in the range of soft rubber – comparable to a bicycle tire or a soft shoe insole.

What Does Shore Hardness Mean?

Shore hardness describes the indentation hardness of elastic plastics. For TPU, the simplified rule is: the lower the Shore A value, the softer and more flexible the material. TPU 85A is significantly softer and more elastic than TPU 95A. Higher Shore A values are generally easier to print and more dimensionally stable, while lower values offer better damping and a softer feel.

Important: The actual flexibility of a part depends not only on Shore hardness but also on part geometry, wall thickness, infill density, print direction, temperature and the specific manufacturer’s filament. Shore hardness alone is not a complete measure of part stiffness.

TPU Variant Comparison

Material	Shore hardness	Flexibility	Printability	Typical application
TPU 85A	85A	very flexible	demanding	soft seals, dampers, protective caps
TPU 90A	90A	flexible	medium	seals, mounts, vibration dampers
TPU 95A	95A	semi-flexible	good to medium	technical flexible parts, protective parts
TPU 98A	98A	slightly flexible	good	robust tough-elastic functional parts

Design Notes for TPU 85A

Flexibility in the part doesn’t depend on Shore hardness alone but strongly on geometry, wall thickness and infill density. Thinner walls and lower infill increase compliance; more solid cross-sections reduce it. Please specify the application and desired behavior when requesting a quote.

Datasheet

Technical datasheet (Polymaker PolyFlex TPU85): polymaker.com/downloads