3D Systems VisiJet CE-BK is a rigid, opaque, high-contrast black UV-curable photopolymer formulated for the ProJet MJP 2500 series MultiJet Printing platforms. The material is processed with co-deposited VisiJet S300 wax support material within a build envelope of 294 × 211 × 144 mm and a native layer thickness of 32 µm. CE-BK is part of the VisiJet CE material family intended for consumer electronics enclosure prototypes, dark bezels, black functional covers, and appearance-critical parts requiring reduced post-print color finishing. Published mechanical values are typically generated on Type I tensile specimens according to ASTM D638-14 and flexural specimens according to ASTM D790-17. The polymer is not a translucent optical material and is not intended as an investment-casting pattern. The dark surface reduces visual contrast during dimensional inspection under structured-light scanning, but the same low reflectivity can mask wax-support residue in blind recesses. Process controls therefore require validated support-removal inspection under low-angle illumination rather than reliance on visible color contrast alone.

Manufacturer-published nominal property values for CE-BK are reproduced below as typical values, not as specification limits. The values correspond to ProJet MJP 2500 Plus builds using default orientation and post-process parameters. Orientation-specific qualification coupons remain necessary for structural applications because layer-boundary effects alter mechanical response along the z-axis.

The tabulated values place CE-BK in the rigid, low-ductility photopolymer class. Tensile modulus of 1,500 MPa and flexural modulus of 1,300 MPa provide structural stiffness suitable for small enclosure covers and non-load-bearing black prototypes. Elongation at break of 8 % is lower than many tough stereolithography resins, so interference snaps and clip features require strain-limited design. The notched Izod value of 24 J/m indicates low energy absorption compared with semi-crystalline thermoplastics such as unfilled polyamide 6. Impact-sensitive components should use ribbing, thickened bosses, and generous fillet radii rather than relying on the polymer to absorb drop impact. Heat deflection temperatures of 52 °C and 44 °C under the respective stress levels restrict CE-BK to low-temperature consumer appliance and indoor electronics environments.

What Build Parameters Govern CE-BK Processing on the ProJet MJP 2500 Plus?

Native processing on the ProJet MJP 2500 Plus uses a fixed MultiJet print head array, and the printer software applies a material-specific UV dose per voxel rather than selecting an independent layer height for each job. CE-BK is dispensed alongside VisiJet S300 support wax, and the two-phase build requires that support material remain in place until the as-built part is transferred to the post-processing station. The as-built part stays on the build tray until wax removal, and the build should be oriented so that drainage channels avoid retained wax in closed cavities. In high-definition mode the nominal z-step is 32 µm, while xy-resolution is governed by the MultiJet print head array rather than selected per material. Fine text or knife-edge features are typically oriented with critical surfaces in the xy-plane because layer-stepping on shallow angles below 10° produces visible banding that is only partially mitigated by post-print smoothing. CE-BK does not require a thermal post-cure step, but residual support wax must be fully removed before any UV clear coat, primer, or adhesive bonding application.

MultiJet Printing with CE-BK differs from stereolithography and fused deposition post-processing because the wax support is removed by heat and subsequent rinsing rather than by mechanical breakaway or solvent dissolution in an aggressive solvent. The support wax allows internal channels and undercuts to be generated without pips or witness marks, but cleaning access must be verified. Long, narrow channels with diameters below approximately 2 mm can retain wax because ultrasonic cleaning fluid does not circulate effectively in blind features. Production-scale MultiJet lines therefore add extended cleaning cycles only for geometries with demonstrated wax retention. CE-BK’s black surface increases the difficulty of detecting thin wax films, so visual inspection requires oblique lighting or ultrasonic imaging for critical channels.

Orientation-Dependent Mechanical Response Is Treated as a Process Variable

Published mechanical values for CE-BK are not sufficient for structural design unless the test coupon orientation matches the printed part orientation. In MultiJet Printing, droplet coalescence and UV cure generate layer boundaries with lower cross-link density than the bulk xy-plane. This can reduce z-direction tensile elongation and impact resistance relative to in-plane values. The manufacturer-published property table does not provide a full z-axis tensile dataset for every distributor batch; published data for this specific configuration is limited. For snap-fit covers and latching features, production groups print flexural elements in the xy-plane and apply a strain ceiling below the 8 % nominal elongation at break. Notched Izod values of 24 J/m reflect xy-plane coupon response and should not be extrapolated to z-loaded bosses or unsupported tab geometries. Build orientation also influences surface stair-stepping and support contact artifacts. Features with shallow angles below 10° to the build plane are oriented steeper to reduce banding unless a machined surface is acceptable.

For dark appearance parts that require metrology, the black surface of CE-BK can reduce optical artifacts in structured-light scanning, but the same dark color can hide crack initiation in thin flexural elements. Thin walls below 1.0 mm are sensitive to distortion during support removal because the flexural modulus of 1,300 MPa allows creep at moderately elevated oven temperatures. Field data from MultiJet Printing service bureaus indicate that CE-BK part distortion is most commonly observed in long, flat covers oriented parallel to the build plane when support removal temperatures approach the 0.455 MPa heat deflection temperature. Supporting the part during wax removal or choosing a steeper build angle reduces the bending moment caused by residual wax mass.

Support Wax Removal and EZ Rinse-C Cleaning Sequence

Parts printed in CE-BK are cleaned in two stages: heated support removal followed by ultrasonic cleaning in VisiJet EZ Rinse-C or a compatible low-alkaline cleaning agent. Because CE-BK exhibits an HDT of 52 °C at 0.455 MPa and 44 °C at 1.82 MPa, the wax-removal temperature must remain below the lower deflection threshold when parts carry residual wax mass or support anchors. Cleaning baths are typically maintained at 35 °C or below to avoid edge softening in thin sections. After cleaning, parts are air-dried under ambient conditions. No thermal post-cure is specified, but direct sunlight or high-intensity UV exposure can drive additional surface polymerization and produce minor color shift. The dark CE-BK surface complicates detection of residual support wax in blind holes; inspection under low-angle illumination or ultrasonic imaging is used on production lines. Published data for long-term solvent exposure of CE-BK is limited; wipe cleaning with isopropyl alcohol should be terminated immediately after residue removal because retained alcohol can promote surface microcracking in thin sections.

Adhesion of paints, primers, and coatings to CE-BK after support removal should be verified by cross-cut adhesion testing according to ASTM D3359. The black photopolymer can be coated with UV-curable topcoats, but solvent-based primers containing ketones, esters, or chlorinated solvents should be screened before production use. Because the material is a thermoset, it does not melt during drying or coating cure cycles; however, exposure above the heat deflection temperature under load can cause dimensional change. CE-BK’s dark color after cleaning is uniform enough for appearance prototypes but is not supplied with a certified color value such as a CIELAB target. If lot-to-lot color consistency is required, incoming material should be verified with a colorimetric instrument using a standard illuminate such as D65.

When CE-BK Replaces General-Purpose Black MJP Materials in Functional Prototype Lines

CE-BK differs from VisiJet M2R-BK in intended use. CE-BK is formulated for high-contrast black appearance and color stability in consumer electronics prototypes, whereas M2R-BK is positioned as a general-purpose black rigid resin. Published property tables for the two materials are not identical; CE-BK’s tensile modulus is lower than several general-purpose VisiJet rigid resins, and its dark opaque color eliminates the need for post-print dyeing of natural or clear resins. Unlike VisiJet M2R-CL, CE-BK is not suitable for light piping, light-transmission fixtures, or flow visualization. Unlike VisiJet M2 CAST, CE-BK is not suitable for investment-casting burnout patterns because the photopolymer does not melt cleanly in dewax furnaces. Transitioning from fused deposition of black ABS to MJP CE-BK also requires changing post-processing assumptions: CE-BK is a thermoset photopolymer, so ultrasonic welding and thermal staking used with ABS are not applicable. Adhesive bonding and mechanical fastening remain viable, but insert installation should use machined or printed pilot bores with low-interference thread designs.

CE-BK is also different from elastomeric or tough MJP materials because it is stiff and relatively brittle at low strain. For consumer electronics applications, the material is used for stationary wearable housing prototypes, small appliance control-panel components, bezels, and optical inspection fixtures where black surfaces reduce stray light reflections. The nominal tensile elongation at break of 8 % limits snap-fit insertion strain. Tapered snap arms with a practical strain ceiling below 5 % are specified unless orientation-specific testing demonstrates otherwise. Thread-forming screws in printed bosses should use pilot holes and low-engagement thread designs. Printed vertical bores can exhibit radial variation at layer boundaries, and critical holes are machined to maintain roundness below 0.1 mm. CE-BK is not used for living hinges, high-impact tool housings, or continuous service above the 0.455 MPa heat deflection temperature.

Assessing Dimensional Stability After Support Removal

Dimensional accuracy for CE-BK parts depends on geometry, orientation, and the support-removal thermal cycle. Published datasheets do not provide a single isotropic shrinkage factor for all features; compensation factors are applied in the printer software and validated by first-article inspection on a feature-specific basis. Thin walls below 1.0 mm are more sensitive to curling during heated wax removal than thick sections because low flexural modulus permits gravity-induced creep. Features below 0.5 mm may be limited by support-wax retention and cleaning access rather than native print resolution. For small reference features, unloaded geometric tolerances are often held within ±0.1 mm, but this is not a supplier guarantee for every material lot or geometry. Moisture uptake in high-humidity storage above 60 % RH can affect check-fixture dimensional stability; desiccant storage is specified for metrology reference assemblies. CE-BK should not be exposed to continuous service above its heat deflection temperature, and creep under load should be evaluated using ASTM D2990 or an equivalent long-term creep method for loaded enclosure clips.

The black surface of CE-BK can be marked, machined, or engraved after cleaning. Machining should use low cutting speeds and adequate dust extraction because the thermoset photopolymer does not produce continuous thermoplastic chips. Holes and slots intended for pressed inserts are often machined after printing rather than printed because as-printed vertical bores can exhibit layer-boundary porosity or radial variation. If inserts are installed with heat-staking methods used for thermoplastic resins, the process is not applicable to CE-BK because the material will not melt and may degrade locally. Press-fit inserts with low interference are preferred, and adhesive bonding with cyanoacrylate or structural acrylic adhesives can be used after surface preparation with isopropyl alcohol wipes followed by immediate drying.

Regulatory Status and Documented Limitations

Supplier documentation for CE-BK does not establish medical, food-contact, or high-temperature regulatory status. The dark pigment and UV-curable chemistry are intended for industrial prototyping and non-regulated consumer goods development, not for implantables or prolonged food-contact applications. Downstream manufacturers must request lot-specific compliance documents before using CE-BK in products subject to electrical and electronic equipment regulations.

Operational boundaries follow directly from the thermoset photopolymer chemistry. CE-BK should not be autoclaved, solvent-welded, or exposed to continuous service above the 0.455 MPa heat deflection temperature. Aggressive cleaners containing ketones, esters, or chlorinated solvents are avoided. Isopropyl alcohol used for short-duration wipe cleaning is removed immediately to reduce the risk of surface microcracking. No thermal post-cure is required, but subsequent UV exposure shifts surface color and should be controlled if appearance-matching is critical. Sections thinner than 0.5 mm are not recommended for load-bearing features because support-removal stresses and cleaning bath exposure can generate edge cracks that are difficult to detect on the black surface.