The product designation 3D Systems VisiJet EBK-ENT-R36 identifies a multi-material photopolymer kit containing two build material formulations: VisiJet CE-BK, a black opaque acrylate-based material, and VisiJet CE-NT, a natural translucent material. The EBK-ENT-R36 commercial SKU is supplied for MultiJet Printing platforms that operate with two heated build material bays and a wax-based support system. The materials are jetted through piezoelectric printheads, planarized by a recoater blade, and cured by UV exposure in the build chamber. The kit is not an adhesive, coating, or casting resin. The individual CE-BK and CE-NT cartridges are recognized by the printer software as separate build materials and must be assigned to discrete solid regions or shells in the CAD model.

Published documentation for the EBK-ENT-R36 kit as a separate datasheet is limited. The individual CE-BK and CE-NT datasheets list mechanical property measurements against ASTM D638-14, ASTM D790-17, ASTM D256-23, and ASTM D648-18. Users qualifying the paired set should not transfer single-material datasheet values to the multi-material transition zone without separate tensile bars or flexural coupons spanning the CE-BK/CE-NT interface. Test coupons should be printed in the same orientation, layer height, and post-cure sequence as production parts.

Which Support Removal and UV Post-Cure Sequence Applies to the EBK-ENT-R36 Pair?

Parts produced with CE-BK and CE-NT are embedded in wax-based support material after the build. Support removal on MJP systems generally follows a two-stage process: a controlled oven melt-out phase followed by heated oil or proprietary solvent immersion. Because EBK-ENT-R36 contains two build materials with different optical density, process heating can be non-uniform if the black CE-BK regions absorb infrared energy more rapidly than natural CE-NT regions. The wax removal station should therefore be profiled with a weighted part load that includes both materials. Thin natural translucent walls should not bear the weight of black sections during melt-out. Published data for the EBK-ENT-R36-specific melt-out temperature and immersion time is limited, so the equipment manufacturer’s recommended range should be bracketed with sacrificial parts at the upper and lower limits.

Production-scale experience on MJP hardware indicates that residual wax in blind channels below 1 mm diameter is the most frequent source of batch-to-batch rejection. Ultrasonic bath cleaning can reduce residual support but may induce cavitation damage on thin CE-NT sections if the part is not fixtured. A consistent post-cure UV dose is also required because incomplete acrylate conversion at the surface can leave a tacky residue and reduce hardness measured by ASTM D2240-15. The UV post-cure unit should be validated for timer or radiometer settings, and parts should be rotated to expose shaded internal surfaces. Operators should avoid stacking parts during post-cure, since contact points can block critical UV wavelengths and create localized under-cure.

VisiJet CE-BK and CE-NT Hardness, Shrinkage, and Solvent Uptake

The CE-BK and CE-NT formulations are rigid engineering photopolymers. The black and natural variants differ primarily in pigment package and optical transmission; the base monomer system is not disclosed in the public safety data sheets. Shrinkage in photopolymerization is a function of monomer conversion and cross-link density, not solely pigment loading. Users measuring dimensional stability should condition parts to equilibrium and record shrinkage against the CAD model using a calibrated optical comparator or CMM. Solvent uptake in CE-BK and CE-NT follows the behavior of cross-linked acrylate networks: short-term exposure to isopropanol is common for cleaning, but prolonged contact with ketones, chlorinated solvents, or aggressive automotive fluids can produce microcracking and loss of tensile elongation. Published chemical compatibility data for EBK-ENT-R36 is limited; immersion testing should follow ASTM D543-21 or equivalent.

Thermal expansion in CE-BK and CE-NT is not commonly disclosed in public literature. If the two materials are used in a housing that undergoes repeated thermal cycling, the assembly should be tested from the minimum to maximum service temperature. Differential expansion at the color transition can create tensile stress at the interface. A conservative measurement method is to precondition parts at 23 °C ± 2 °C and 50 % ± 5 % RH according to ISO 291:2008, then measure critical dimensions before and after the thermal cycle. Published data for the specific EBK-ENT-R36 configuration is limited, so internal CTE comparison should be performed with a thermomechanical analyzer or equivalent calibrated instrument.

When the Kit Is Compared Against M2R and M2G VisiJet Material Families

The EBK-ENT-R36 kit differs from single-material VisiJet M2R and M2G offerings by supplying a black and natural material pair in one ordering SKU. M2R clear and gray materials are often used where a single neutral rigid material is acceptable. CE-BK provides opaque black identification surfaces; CE-NT provides a natural translucent appearance without post-process painting. The mechanical property overlap between CE-BK/CE-NT and other rigid VisiJet photopolymers has not been published as a single comparative table for the EBK-ENT-R36 configuration. A material substitution therefore requires side-by-side tensile testing according to ISO 527-2:2012 or ASTM D638-14 using the same MJP platform, layer height, and post-cure protocol. Substitution based solely on visual appearance or datasheet hardness is not technically sufficient.

Tensile, Flexural, and Impact Documentation Gaps Across the EBK-ENT-R36 Pair

Individual CE-BK and CE-NT documentation may report tensile strength, tensile modulus, elongation at break, flexural strength, flexural modulus, notched Izod impact, and heat deflection temperature. The test methods commonly referenced are ASTM D638-14, ASTM D790-17, ASTM D256-23, ASTM D648-18, and ISO 75-1/2:2020. A separate EBK-ENT-R36 combined datasheet that reports the interface properties of CE-BK and CE-NT printed in the same build is not always published. Where a value is not disclosed, the appropriate engineering response is to state that published data for the specific configuration is limited and to generate internal qualification data. Do not interpolate properties between the two materials across the transition boundary.

Because the EBK-ENT-R36 SKU is regionally coded, cartridge volumes and fill weights can vary by regional packaging. The operator should verify that the printer’s material bay mapping matches the cartridge RFID or barcode recognition. Mismatched insertion of CE-BK into the wrong bay can produce build aborts or contamination at the fluid couplings. The system software generally locks material selection to the assigned bay; production records should capture cartridge lot number, date of first use, and printer serial number to support traceability under ISO 9001:2015 or equivalent quality management requirements.

What Limits Piezoelectric Jetting Reliability in CE-BK and CE-NT Cartridges?

Jetting reliability for CE-BK and CE-NT is governed by low-shear viscosity, surface tension, and pigment dispersion stability. The printhead firmware compensates for normal viscosity variation by adjusting piezoelectric drive voltage, but the factory acceptance band is not operator-adjustable. Cartridges stored below recommended room temperature can exhibit temporarily elevated viscosity; cartridges heated above the recommended range can age prematurely. EBK-ENT-R36-specific viscosity versus shear rate data is not published. On the production floor, missing jets, satellite droplets, or banding parallel to the recoater direction indicate that the material or printhead condition has shifted outside the control envelope. The response is not to modify the material but to replace the cartridge, clean the printhead, and verify the planarizer gap.

Do not dry CE-BK and CE-NT cartridges in a conventional desiccant dryer. The materials are supplied as sealed liquid photopolymers; heating under vacuum or air can polymerize the material prematurely or alter jetting viscosity. The cartridges should be stored away from UV sources and fluorescent light. If the material has been exposed to temperatures below 10 °C during transport, the cartridge should be conditioned at room temperature for a period specified by the manufacturer before insertion into the printer. These constraints are not unique to EBK-ENT-R36 but apply to jettable acrylate photopolymers generally.

For machined features, CE-BK and CE-NT can be drilled, reamed, and tapped after post-cure, but cutting speeds should be reduced compared with injection-molded ABS because thermoset photopolymers can chip or melt at high feed rates. Machined edges at the CE-BK/CE-NT transition may show material pull-out if the tool exits the black region and enters the natural region. Climb cutting and sharp tooling are preferred. The resulting surface should be inspected under 20× magnification for interface delamination. No published machinability data for EBK-ENT-R36 is available, so feed and speed parameters must be validated on sacrificial parts.

If Mechanical Loading Crosses the CE-BK/CE-NT Interface in Printed Housings

When a printed housing combines CE-BK and CE-NT regions under load, the failure path may localize at the interface rather than in either bulk material. Tensile bars printed with the interface perpendicular to the loading axis should be tested according to ASTM D638-14 and compared to single-material controls. If the interface strength is not published, a conservative design approach assumes the transition zone is a weld line. The designer should avoid placing the material boundary at a snap-fit root, living hinge, or sealing lip. For sealing applications, the CE-NT surface should be checked for flatness after post-cure because differential shrinkage can create step offsets at the color change. Measurement should be performed with a calibrated dial indicator or CMM, and the measured step height should not exceed the seal manufacturer’s specified gap tolerance.

Painting and coating adhesion tests should include cross-cut adhesion according to ISO 2409:2020 or ASTM D3359-23. Residual wax and under-cured acrylate are the two most common causes of coating failure. A solvent wipe alone is not sufficient; post-cure followed by light abrasive blasting or sanding of the surface improves mechanical anchoring. The black CE-BK surface may require different primer timing than the natural CE-NT surface because pigment can affect surface energy. Adhesion should be tested on both materials and on the transition line.

Material qualification for EBK-ENT-R36 should therefore proceed as a paired set, not as two independent materials. Physical performance tests across the transition boundary, support removal process capability, and document status should be recorded in the production batch record. Where public datasheet values are absent, the qualification record must state that published data for the specific EBK-ENT-R36 configuration is limited and that the internal test data supersedes marketing literature.