Product designation Covestro Addigy GPC 3D1000C 000000 identifies an unfilled polycarbonate feedstock prepared for fused filament fabrication. The model code GPC 3D1000C distinguishes the grade within the Addigy 3D printing portfolio, while the suffix 000000 corresponds to the standard black color index in Covestro’s product labelling, not to a reinforcing filler or flame-retardant package. The material is based on a bisphenol-A polycarbonate continuous phase and is intended for open-chamber or enclosed FFF/FDM machines where a nozzle setpoint between 270 °C and 310 °C and a bed setpoint between 90 °C and 110 °C can be maintained. Published batch data should be checked against the certificate of analysis, because melt flow, pigment dispersion, and diameter tolerance can vary between production runs. The filament is typically supplied in desiccant-sealed spools and must be protected from atmospheric humidity before feeding; hydrolysis in the hot end will reduce interlayer fusion and impact performance. This grade is not a PC-ABS alloy and is not a filled polycarbonate compound. Its practical distinction from PLA, PETG, and ABS appears primarily in thermal capability, notch sensitivity, and processing demands rather than in tensile modulus alone. The material requires all-metal hot ends, polyimide or PTFE-free thermal barriers rated above 260 °C, and a print environment that suppresses differential shrinkage on parts with long unsupported spans. The black color designation assists in producing opaque functional components without post-print painting but may alter the surface contrast of laser-marked legends compared with natural or white polycarbonate.

What Processing Envelope Does Addigy GPC 3D1000C 000000 Demand?

Polycarbonate filament processing is governed by two interacting constraints: residual moisture content and the temperature window between melt flow and thermal degradation. Polycarbonate reaches measurable moisture pickup in ambient air. At 23 °C and 50 % relative humidity, a conditioned film or pellet surface can equilibrate near 0.15 wt% water according to ISO 62:2008, while saturated immersion values are higher. Fused filament fabrication requires moisture below roughly 0.02 wt% before extrusion. Drying in a desiccant dryer at 80 °C for 4 h to 6 h, or overnight in a sealed hopper with a dew point of −40 °C, is the standard preconditioning practice. Undried filament may extrude with splay, surface silver streaks, and audible popping at the nozzle; more critically, hydrolysis reduces molecular weight and produces brittle interlayer boundaries that are not recoverable by annealing after printing. Karl Fischer titration using ISO 15512:2019 is the relevant moisture verification method for incoming material lots.

The melt viscosity of unfilled polycarbonate for filament extrusion generally corresponds to an MVR range of approximately 9 cm³/10 min to 11 cm³/10 min when measured at 300 °C and 1.2 kg according to ISO 1133-1:2022. Lower MVR grades improve melt strength but increase extrusion backpressure and may require direct-drive extruders with high torque. The Addigy GPC 3D1000C grade should be processed in an all-metal hot end; PTFE-lined thermal barriers degrade above 260 °C and are unsuitable. Brass nozzles are acceptable for this unfilled grade, but long dwell times at temperatures above 300 °C should be minimized because prolonged residence can promote yellowing and chain scission. Hardened steel or stainless steel nozzles are not required for wear resistance unless the machine is shared with abrasive filled filaments, though thermal conductivity differences may require a 5 °C to 10 °C increase in setpoint compared with brass.

Layer adhesion and warpage control are the principal production bottlenecks. On open-frame machines without heated chambers, the combination of a 100 °C bed and an ambient temperature below 20 °C can create edge lift on flat parts with a build footprint exceeding 100 mm × 100 mm. Enclosed printers with a chamber temperature of 60 °C to 80 °C substantially reduce this failure mode. Active part cooling should be disabled during the first layers and limited to 5 % to 15 % fan speed after initial shell formation; excessive cooling induces internal stress and lowers interlayer impact strength. Recommended bed surfaces include polycarbonate sheets, PEI films, or glass with a polycarbonate-compatible adhesive. Dimensional reference dimensions should be measured after 24 h conditioning at 23 °C and 50 % relative humidity, not immediately after removal from the build plate.

Where production-scale equipment is used, batch-to-batch variance in filament ovality is a more common cause of feed failure than moisture alone. A 1.75 mm filament with ovality greater than 0.05 mm can produce under-extrusion or intermittent grinding in single-gear extruder drives. Incoming spools should be sampled at multiple points with a micrometer graduated to 0.01 mm, and the spool hub should rotate freely to prevent uneven tension. Filament runout sensors are advised on multi-hour builds, since black PC parts can delaminate cleanly at a single layer if material starvation occurs and printing resumes without sufficient remelt. Post-print annealing at 120 °C for 30 min per 5 mm of section thickness can reduce residual stress but should be validated on a sacrificial part because anisotropic shrinkage of 0.3 % to 0.7 % may occur.

Specific mechanical comparisons must be read against ISO 527-1/-2 and ISO 178 data, not against nominal supplier marketing values. Published values for unfilled polycarbonate filament are generally represented by the following ranges; batch-specific certificates for Addigy GPC 3D1000C 000000 may fall within or slightly outside these intervals depending on pigment loading and extrusion history.

Electrical, Flammability, and Chemical Resistance Boundaries

Polycarbonate occupies a specific position in electrical enclosure prototyping because it provides both rigidity and dielectric strength. Unfilled grades typically exhibit surface resistivity above 10¹⁴ Ω when tested according to IEC 60093, and dielectric strength values in thin plaques are commonly reported in the range of 20 kV/mm to 35 kV/mm under IEC 60243-1. These values support use in insulative housing prototypes and non-live electrical components, but they should not be extrapolated to high-frequency or high-humidity service without printed-part testing. The black 000000 pigment package may influence surface resistivity only marginally; the controlling variable is the continuous polycarbonate matrix.

Flammability classification for a printed part is not identical to the classification of the base pellet or filament. Most unfilled polycarbonate compounds are classified under UL 94 as HB at 1.5 mm or 3.0 mm, with V-2 behavior possible in specific formulations using flame-retardant additives. The Addigy GPC 3D1000C grade should be assessed on printed specimens of the intended wall thickness because voids, interlayer boundaries, and surface roughness create ignition paths that are absent in injection-moulded plaques. Users needing formal UL recognition must test the final printed part, because the filament supplier cannot certify all printer geometries and slicing parameters.

The chemical resistance profile of polycarbonate imposes a stricter operational boundary than heat resistance. Aromatic hydrocarbons, chlorinated solvents, and ketones can induce environmental stress cracking, especially in parts with residual printing stress. Acetone is incompatible and should not be used for cleaning; isopropanol may be tolerated for brief wipe cleaning on unstressed surfaces but has caused cracking on highly stressed clamp features in field trials. Strong alkaline cleaning agents and amine-bearing formulations should be avoided. The grade is not recommended for continuous immersion in hot water above 60 °C unless the part is annealed and the geometry is low-stress, because hydrolytic degradation proceeds more rapidly at elevated temperature. These restrictions are characteristic of unfilled polycarbonate and form a major boundary against selecting the material for chemical process equipment components.

When Sustained Thermal Load Exceeds the Capability of PETG and ABS

The thermal distinction of Addigy GPC 3D1000C appears most clearly in fixtures, jigs, and low-volume functional parts that experience repeated exposure above 90 °C. Amorphous PETG begins to soften perceptibly near 70 °C under low load, while standard ABS retains form to approximately 95 °C to 105 °C depending on grade and annealing. Unfilled polycarbonate can operate with dimensional stability through a higher range. Heat deflection temperature under 1.8 MPa flexural stress, measured by ISO 75-1/-2, is commonly reported near 124 °C to 128 °C for unfilled PC filament. Under the less severe 0.45 MPa load, HDT/B values generally reach 135 °C or higher. This permits use in soldering fixtures, paint-curing racks, injection-mould tooling inserts, and automotive interior components near heat sources where ABS or PETG parts would warp or lose clamping force.

A further difference from common printing grades is the absence of an ABS or styrenic phase. PC-ABS alloys reduce notch sensitivity and lower the melt processing temperature compared with polycarbonate, but they usually sacrifice some upper-use temperature and chemical resistance. The GPC 3D1000C grade is formulated as an unfilled polycarbonate, so it retains the base polymer’s high-temperature performance and impact character, but it also retains polycarbonate’s greater notch sensitivity and tendency to stress-crack under solvent exposure. This distinction matters in snap-fit designs: a PC part with sharp internal corners may fail at lower repeated deflection than a PC-ABS blend if the geometry is not redesigned with generous radii. Printed polycarbonate also tends to show anisotropic impact behavior; tensile bars printed flat and tested parallel to the extrusion direction generally return higher elongation at break than bars loaded through the layer plane.

In practical workshop use, the filament is selected when a component must hold a press-fit insert under continuous heat. For example, a forming fixture carrying an embedded metal bushing may survive repeated cycles at 110 °C air temperature where ABS and PETG would relax. However, the part must be allowed to reach thermal equilibrium before measuring critical dimensions, because the coefficient of linear thermal expansion of unfilled PC is typically near 65 × 10⁻⁶ K⁻¹ to 70 × 10⁻⁶ K⁻¹ in the 23 °C to 80 °C interval according to ISO 11359-2. Large parts can grow measurably between room temperature and service temperature, and clamping points must permit this movement. The same expansion coefficient creates dimensional mismatch when polycarbonate parts are bolted to steel or aluminium tool plates; slotted holes or thermal isolation washers are recommended for spans above 200 mm.