PolyJet machines jet photopolymers, and their material range is built around one capability the process has and others do not: two base resins can be jetted together in controlled proportions, producing a continuous range of intermediate materials from one pair. That is what makes graded stiffness in a single part possible.
The families
Rigid opaque resins for general models, available in a range of colours. Rigid clear resins that polish to transparency for lenses, light pipes and fluid visualisation. Rubber like resins across a wide hardness range for grips, seals and gaskets. High temperature resins for parts that see heat during testing. Biocompatible grades for medical and dental applications with their own certification.
Digital blending
Jetting two base resins in controlled ratios within the same part produces intermediate materials, so a component can be rigid at one end, rubbery at the other, and anything in between along its length. That is used for anatomical models with realistic tissue stiffness, for prototypes of overmoulded products, and for demonstrating a design that will later be two shot moulded.
Colour
Colour capable machines jet pigment along with the resin, producing full colour parts straight from a textured model. That is heavily used for surgical planning models, packaging and consumer product review, where being able to show the final graphics on the final shape in one object saves a great deal of argument.
The durability limit
These are photopolymers, not engineering thermoplastics. They creep under sustained load, they are less tough than moulded parts, many degrade and yellow under ultraviolet light within months, and the rubbery grades have worse compression set than moulded elastomers. So the material set is superb for communication and validation and is not a route to end use parts.
Questions people ask about polyjet materials
What is digital material blending?
Jetting two base photopolymers together in controlled proportions so a single part can vary continuously between rigid and rubbery along its length.
Can PolyJet parts be used in service?
Generally no. The photopolymers creep, are less tough than moulded parts and many degrade under ultraviolet light within months.
Are clear PolyJet parts transparent straight off the machine?
No. They come off translucent and need polishing or a clear coat to reach genuine transparency, which is labour that should be in the quote.
Are there biocompatible PolyJet materials?
Yes, with their own certification, used for medical and dental applications. The certification applies to specific resins and specific processing rather than to the machine.