The 3D Systems VisiJet RBK-RCL-L70 Multi-Material Composites kit is a paired build-material supply for MultiJet Printing systems configured to jet the VisiJet CR-BK black rigid photopolymer and the VisiJet CR-CL 200 clear rigid photopolymer in the same additive build. The catalogue designation identifies the two-cartridge format rather than a single formulated resin. VisiJet CR-BK functions as the pigmented structural phase; VisiJet CR-CL 200 functions as the transparent or translucent phase. The kit is used for non-marital engineering models, fluidic demonstration devices, light-piping test pieces, assembly fixtures, and prototype housings in which regional differentiation of clear and black rigid sections removes the need for post-print painting or secondary adhesive assembly. The two resins are jetted, UV-processed, and supported within the same MJP platform; the supplier controls cartridge recognition and material-use parameters through the printer’s consumable interface. Published mechanical data for the neat constituent resins are available from supplier datasheets and are reported under ASTM coupon conditions. Published data for the RBK-RCL-L70 multi-material transition zone is limited to supplier technical bulletins and application development reports. The kit is not an elastomeric overmolding system, and the L70 suffix should not be interpreted as a Shore 70A hardness rating without reference to the supplier’s current material specification. Users needing a low-modulus, high-elongation response or a Shore A-scale elastomer should not use this kit in place of a durable or elastomeric VisiJet grade.

What Distinguishes a Mixed-Cartridge RBK-RCL-L70 Build from Single-Resin VisiJet CR-BK or VisiJet CR-CL 200 Jobs?

In a single-resin configuration, the build file contains either VisiJet CR-BK or VisiJet CR-CL 200 as the sole build material, and the part is monolithic with respect to composition. In the RBK-RCL-L70 composite configuration, both materials are available within the same build file and are assigned to defined regions, bodies, or voxel groups at the CAD or print-preparation stage. The MJP platform sequences jetting and UV exposure so that the two resins form a polymerized transition zone within the same layer and across build layers. The interface is therefore not a separately cured adhesive bond line, nor is it a coated pigment layer on the surface of a clear part. It is generated by the coexistence of both reactive liquids in a localized voxel field, followed by UV solidification. That production mechanism separates the RBK-RCL-L70 kit from post-process painting or overmolding operations. Coatings applied after printing can delaminate, scratch, or alter dimensional tolerance; in the composite build, the black phase is present through the affected cross-section or selected layer depth, depending on the build file definition.

The mixed-cartridge approach also differs from post-print bonding of separately printed CR-BK and CR-CL 200 components. In an adhesively bonded assembly, the bond line contains the adhesive’s own shrinkage, modulus, and cure profile. In the multi-material MJP build, the two resins meet in a supplied liquid state, and the boundary is established before the part is fully solidified. The result is a continuous photopolymer network with a compositional gradient at the transition, but the transition is not an isotropic bulk material. Mechanical loading across the transition zone may produce failure at or near the interface at stresses below the neat-resin ultimate values. Published data for this specific configuration is limited, and suppliers do not currently provide an interface fracture toughness value for the CR-BK/CR-CL 200 boundary under a standardized test such as ASTM D5528 or ISO 25217. Users should therefore validate part-level performance when the interface is placed in a load path.

Compared with the same supplier’s durable VisiJet grades, the RBK-RCL-L70 kit remains a rigid, high-modulus system. The clear phase is transparent in the as-built condition but requires surface finishing for optical clarity. The black phase is rigid and non-elastic. The kit is not a two-color flexible composite; Shore D values for the neat resins are reported in the 81 to 80 range, which places the material in the rigid photopolymer class. This is a deliberate performance boundary. If an application requires vibration damping, impact absorption, or snap-fit deflections associated with an elongation above 20%, the user should evaluate a durable VisiJet M2G or equivalent engineering resin instead. The RBK-RCL-L70 formulation is intended for dimensional stability, regional transparency, and rigid-part contrast, not for rubber-like compliance.

Mechanical Property Data for the Neat Resins Are Reported Under ASTM Coupon Conditions

The following table consolidates representative supplier-reported values for post-cured neat coupons of VisiJet CR-CL 200 and VisiJet CR-BK. The values apply to monolithic test bars, not to composite transition specimens. Lot-specific certificates of analysis govern final production use.

The black pigment system in VisiJet CR-BK reduces tensile elongation and notched impact relative to the clear CR-CL 200 grade. The flexural modulus remains comparable to the clear grade and may be slightly higher as a result of pigment-filler stiffening. These neat-resin differences matter in mixed RBK-RCL-L70 builds because a tensile feature spanning the black and clear phases will not simply average the two sets of properties. The transition region can contain local compositional gradients, void-like boundaries, or stress concentrations arising from the jetting sequence. For structural simulations, the clear phase may be represented by the CR-CL 200 data, and the black phase may be represented by the CR-BK data, but the interface should not be modeled as a perfect bonded tie with neat-resin strength. There is no supplier-published tensile adhesion value for the CR-BK/CR-CL 200 boundary under an established interfacial test. Published data for this specific configuration is limited, and batch-to-batch variation in pigment dispersion may influence local clarity, viscosity, and photo-cure response at the transition.

Support Removal, Post-Curing, and Optical Transmission Limits

The MJP platform deposits a dedicated support material around the build material. Support removal for the CR-BK and CR-CL 200 kit follows the printer supplier’s documented melt-away or solvent-assisted sequence, depending on the support material designated for the platform. Parts may be placed in an oven maintained within the supplier-specified support-removal temperature window, followed by an agitated bath to remove residual support. The use of unapproved solvents or excessive oven dwell can craze the clear phase, distort thin black sections, or weaken the multi-material interface. Operators should use the support-removal equipment and settings specific to the MJP platform rather than applying heat or solvent protocols from other photopolymer systems.

VisJet CR-CL 200 is not an optically finished transparent polymer in the as-built state. Layer lines, support-contact surfaces, and internal scatter reduce transmission and haze. The supplier does not publish an ASTM D1003 total luminous transmittance or haze value for the RBK-RCL-L70 composite. If optical transmission is required, the clear region must be polished, clear-coated, or surface-smoothed after support removal. Polishing of CR-CL 200 may raise local temperature and can alter surface stress; polished composite parts should be dimensionally re-inspected because material removal changes wall thickness. For light-piping applications, internal channels printed with support must be flushed completely, as residual support can block optical path sections. Published data for this specific configuration is limited.

The black phase of the RBK-RCL-L70 kit does not require post-curing for color development; its pigmentation is present in the reacted polymer matrix. The clear phase may show gradual color shift under high-humidity conditioning or prolonged ultraviolet exposure. No supplier-published accelerated weathering data under ASTM G154 or ASTM G155 is available for the multi-material interface. Users designing components for outdoor exposure should evaluate the part with application-specific UV and condensation cycles. Dimensional tolerance on the composite build is also influenced by support removal and manual finishing. The printer’s specified linear accuracy is not a property of the resin alone; it applies to a defined build orientation, geometry, and post-processing workflow. In multi-material builds, feature edges at the black/clear boundary may show a visible mixed-pixel zone that must be considered in cosmetic acceptance criteria.

When Environmental Exposure or Solvent Contact Is Specified on the Engineering Drawing

When the application specifies water contact, chemical cleaning, or humid thermal cycling, the RBK-RCL-L70 kit should be characterized under the relevant test standard before committing to production. Water absorption can be conducted under ISO 62:2008 or ASTM D570. The clear phase is more visually sensitive to absorbed moisture than the black phase; haze may develop in translucent sections after prolonged immersion at elevated temperature, even when the bulk mechanical properties remain within specification. This is a boundary condition that must be validated experimentally. The supplier’s neat-resin datasheets do not currently provide a water absorption coefficient for the composite transition zone. For parts requiring tight optical stability, a clear-barrier coating may be necessary, but coating adhesion should be verified separately on both the clear and black surfaces because surface energy and pigment distribution differ.

Solvent contact must be restricted to those agents listed in the supplier’s material handling documentation. Alcohols may be used for short-duration cleaning, but prolonged immersion in isopropyl alcohol can induce stress cracking or surface attack in rigid photopolymers. Ketones, chlorinated solvents, and strong alkaline cleaning solutions should be excluded unless compatibility is demonstrated on production-representative composite coupons. The material is not classified as a solvent-welded or solvent-tolerant thermoplastic. Because both phases are crosslinked photopolymers, solvent-induced swelling is generally low but not zero; the transition zone can absorb differential strain if one phase swells more than the other. For fluidic parts, chemical compatibility should include a burst-pressure test after the intended exposure, not merely a visual inspection.

Thermal cycling across the black/clear boundary should be considered when the part experiences repeated excursions above 45°C. The short-term heat deflection temperatures reported for the neat resins do not provide a fatigue or creep rating for the composite interface. Differential thermal expansion may be minor because the two resins are chemically related, but the black pigment alters the thermal expansion response of the clear phase. For parts with a long interface, thermal cycling may produce hairline separation at the transition after repeated exposure. The supplier does not publish a thermal cycling standard for the RBK-RCL-L70 kit; users should define a test profile based on the application’s maximum service temperature, dwell time, and ramp rate. Published data for this specific configuration is limited.

Regulatory documentation for the RBK-RCL-L70 kit is controlled through the supplier’s Safety Data Sheet and compliance declarations. The kit is typically referenced under RoHS Directive 2011/65/EU and REACH Regulation EC No 1907/2006. The uncured resin cartridges carry handling and disposal requirements for photopolymer materials. No independent food-contact or medical-use statement is supplied for this configuration under FDA 21 CFR 177 or ISO 10993. End users must request an appropriate compliance letter if the part is intended for regulated body-contact, food-contact, or medical-housing applications.

Parts containing alternating CR-BK and CR-CL 200 sections for fluidic manifolding should be pressure-tested after support removal and any polishing operation. Leakage at the mixed-pixel interface may not appear in visual inspection and may only become measurable under internal pressure or gas-permeation testing. The user’s internal burst-pressure procedure should therefore be applied to production-representative parts with the same build orientation and layer thickness. A neat-resin coupon test is not sufficient to establish interface integrity. Published data for this specific configuration is limited, and verification remains a process-specific requirement.