Stratasys RIGUR™ simulated polypropylene photopolymer and TANGOBLACKPLUS FLX980 black rubber-like photopolymer are specified as a paired material combination for multi-material PolyJet systems. The primary material, RIGUR (RGD450), is a rigid but ductile photopolymer formulated to approximate the flexural response and failure strain of unfilled polypropylene. The secondary material, TANGOBLACKPLUS FLX980, is a black elastomeric photopolymer with a low Shore A hardness. The two materials are not blended in a resin drum before printing; they are jetted through independent model-material channels and combined at the voxel level during layer formation. This produces a continuous part in which a stiff polypropylene-like structure and a soft elastomeric surface or hinge can transition without an adhesive interface. Typical engineering applications include snap-fit lids, living hinges, overmolded consumer-product grips, gasketed enclosures, and fixture prototypes that would otherwise require sequential injection molding or manual assembly. The combination is not intended as a replacement for all injection-molded polypropylene parts; rather, it is used where the build geometry must contain both semi-rigid and elastomeric regions in a single additive build.

The material designation appears in printer software as a digital material pair rather than as a single resin name. In GrabCAD Print or Objet Studio, RIGUR is selected as the primary model material and TANGOBLACKPLUS FLX980 as the secondary material when the user defines a digital-material mixture or assigns separate shells to different regions. The software limits the allowable mixture ratios to those validated by the manufacturer; therefore, the phrase “RIGUR/FLX980” describes a family of cured photopolymer compositions whose exact mechanical values depend on the selected ratio and print mode.

What Mechanical Property Envelope Defines the RIGUR/FLX980 Mixed-Material Set?

Mechanical response is dependent on print orientation, layer thickness, and the volumetric ratio of the two materials. In the pure RIGUR state, published datasheet values place tensile strength in the 40–50 MPa range and elongation at break in the 40–60 % range under ASTM D638-14. This elongation is significantly higher than the 10–25 % typical of VeroWhitePlus-class rigid photopolymers, which is the basis for the simulated polypropylene designation. The flexural modulus of RIGUR is reported in the 1300–1700 MPa band under ASTM D790-17, roughly half the modulus of many Vero family materials and therefore closer to unfilled polypropylene in bending response. In the pure FLX980 state, Shore A hardness is reported as 26–28 A under ASTM D2240-15, and tensile strength is reported in the 0.8–1.5 MPa range with elongation at break of 170–220 % under ASTM D638-14. The property table below summarizes the two boundary conditions; intermediate digital-material blends fall between these values and are controlled by the printer software’s material-ratio settings.

The tabulated values represent the two boundary conditions. They are taken from published material datasheets and are subject to batch and printer calibration variation. Intermediate digital-material blends cannot be derived by simple linear interpolation between the boundary conditions because the cured polymer network is not a homogeneous mixture; the rigid and elastomeric phases form interpenetrating or voxel-adjacent domains whose hardness, tensile strength, and elongation depend on both volume fraction and spatial distribution. Published data for the full range of intermediate mixtures is limited; therefore, any critical design value for a specific ratio should be confirmed on a printed coupon using the final build orientation.

During production-scale builds on Connex-class platforms, the RIGUR/FLX980 combination is typically processed at a layer thickness of 16 µm in high-quality mode or 30 µm in high-speed digital-material mode. The printer must be configured with at least two model-material bays and a compatible support material such as SUP705 or SUP706; the support is removed after printing with water-jet equipment for the non-soluble grade or an alkaline bath for the soluble grade according to the manufacturer’s documented concentration and temperature window. Printhead temperature and UV curing intensity are controlled by the system firmware and are not user-adjustable, but build chamber relative humidity outside the 30–70 % range can alter support removal and surface quality on full-height builds. Because PolyJet photopolymers cure by radical photopolymerization, residual uncured monomer can remain in blind recesses when thick FLX980 sections exceed the manufacturer’s maximum recommended wall thickness; post-curing in a UV chamber should follow the documented time and intensity limits for the specific part mass. The interface between RIGUR and FLX980 is formed before full conversion of each voxel, producing a gradient transition rather than a discrete bond line; this reduces interfacial stress concentration but also means that published tensile data for bulk RIGUR or bulk FLX980 should not be used directly for thin overmolded sections. For critical dimensions, tensile coupons should be printed in the final build orientation and tested under ASTM D638-14 or ISO 527-2:2012.

Support removal conflicts arise when an outer RIGUR shell encloses a large FLX980 grip volume. The water-jet or alkaline solution must reach the rubber-like surface through access openings; if the shell is fully closed, the support cannot be fully removed. Recommended practice is to design openings sufficient for support evacuation; the manufacturer’s design guide specifies minimum access dimensions for enclosed volumes. Large FLX980 sections can also exhibit resin pooling in concave features during printing. The layer roller and vacuum system typically manage this, but poor feature aspect ratios can produce surface defects that require additional finishing. Batch-to-batch variance in the FLX980 reservoir is a documented operational concern in multi-shift production; Shore A drift can occur if cartridge lot changes are not recorded. Published data for this specific configuration is limited, but in-line Shore A verification is used in production settings to detect shifts at the start of each build.

When Overmolding Simulation Requires Variable Shore Hardness

Overmolded prototypes are produced by assigning a RIGUR core and a FLX980 shell or local region. The printer’s digital material editor defines the shell hardness by the ratio of the two materials. The software presents only ratios that have been qualified by the manufacturer; therefore, the range of attainable Shore A values is not continuous in the mathematical sense but consists of validated steps. In practice, the steps are sufficiently small to represent Shore A values from approximately 40 A to 95 A depending on the selected digital-material set; however, published data for each step should be read from the current software material database and not assumed from generic polyurethane behavior. The transition between RIGUR and FLX980 can be sharp or graded across a specified thickness. A graded transition reduces stress concentration at the interface in flexural cyclic tests, but it can complicate surface finish because the mixed material zone may have a different response to support removal. For living hinges, a discrete zone of pure RIGUR is often preferable to a digital blend because the blend may lose the elongation needed for repeated flexure. Published fatigue-cycle data for this specific combination is limited; functional prototypes should be cycled to the intended number of closures before design sign-off.

PolyJet parts containing FLX980 should not be exposed to temperatures above 45 °C for prolonged periods if dimensional stability is critical, because the elastomer and the mixed interface can soften. Solvent exposure to ketones, esters, and chlorinated cleaning agents can cause swelling or surface tack. Cleaning should be limited to isopropyl alcohol or soap and water, followed by thorough drying. For handling during assembly, nitrile gloves are recommended because prolonged skin contact with uncured residual resin can cause sensitization; fully cured surfaces are less reactive but should still be handled with standard industrial hygiene. The cured material is not classified for food-contact or medical use unless the user obtains formulation-specific certification under the relevant regulation; the black pigment and residual support chemicals can leach under aggressive extraction conditions.

Comparative Differences from Single-Material PolyJet Photopolymers

Compared with VeroWhitePlus and VeroClear, RIGUR has a lower flexural modulus and higher elongation at break. VeroWhitePlus is typically specified at 50–65 MPa tensile strength and 10–25 % elongation under ASTM D638-14; its higher crosslink density provides a stiffer, more brittle response. RIGUR is selected when the prototype must bend, snap, or tolerate repeated assembly without cracking. Compared with TangoPlus FLX930, TangoBlackPlus FLX980 has a similar Shore A range but is colored black; the pigment loading can change surface energy and may influence paint adhesion or solvent uptake. Compared with Agilus30, FLX980 is an earlier-generation elastomer and may not match the tear strength or elongated build envelope of Agilus30 on newer systems. The primary reason to specify the RIGUR/FLX980 combination is the need for a single-build rigid-to-elastomer architecture; if the part is entirely rigid, a Vero material may offer better surface finish and dimensional accuracy, while if the part is entirely elastomeric, Agilus30 or TangoPlus may offer better mechanical stability.

Compared with injection-molded polypropylene, RIGUR is a thermoset photopolymer rather than a semicrystalline thermoplastic. The heat deflection temperature of RIGUR under 0.45 MPa is below 50 °C, whereas unfilled polypropylene can carry sustained loads at service temperatures above 80–100 °C depending on formulation. RIGUR also exhibits higher water absorption than polypropylene and can be affected by prolonged exposure to UV and certain solvents. The RIGUR/FLX980 combination is therefore not a direct substitute for production-grade polypropylene in elevated-temperature or outdoor applications. Its value lies in reducing assembly steps during prototyping and in producing PP/TPE-like geometries that cannot be economically injection-molded in low volumes. Where long-term creep, fatigue, UV stability, or food-contact compliance are required, the user should transition to qualified thermoplastic production materials after using the PolyJet combination for form and fit iteration.

For prototype validation under ISO 10993-5 or USP Class VI, users must request material-specific certificates from Stratasys for the exact printed configuration. General datasheet values do not constitute biocompatibility certification. The same limitation applies to flammability classifications under UL 94 and to electrical resistivity claims; any compliance statement must be tied to a tested coupon printed in the final orientation, layer thickness, and post-processing condition.