Clariant White Polyamide 6 3D Printer Filament is an unfilled, white-pigmented polyamide 6 monofilament for fused filament fabrication. The product is ordered by resin family, color, and nominal diameter — 1.75 mm or 2.85 mm — rather than by a separate numerical model code. The stock-keeping model is therefore the full descriptor Clariant White Polyamide 6 3D Printer Filament; distribution documentation may carry an internal PA6-W or batch-specific designation, but no uniform global catalog number is publicly available for this single white variant. Published lot-specific datasheets for this exact Clariant white filament are limited. The engineering values reported below are representative of unfilled PA6 monofilament and must be verified against the certificate of analysis supplied with the spool before tooling or end-use part qualification.

Filament diameter and ovality are measured with a two-axis laser micrometer at the production spool. Engineering PA6 filament acceptance is commonly held at ±0.05 mm on diameter with 0.03 mm maximum ovality, but the lot-specific Clariant certificate is the governing document. A deviation of 0.05 mm in a 0.4 mm nozzle changes volumetric throughput by approximately 2–3%; when combined with moisture uptake, that deviation can move the melt from a stable extrusion condition to under-pack or stringing.

Why Moisture Uptake Rather Than Extrusion Temperature Determines White PA6 Print Stability

Polyamide 6 absorbs water by hydrogen bonding at the amide groups. At 23 °C and 50% RH, an unfilled PA6 test specimen equilibrates to approximately 2.5–3.0 mass% moisture; saturation in water reaches 9.0–10.0 mass% per ISO 62:2008. When wet filament enters the hotend, the water vaporises above 100 °C and produces steam pores at the nozzle, intermittent extrusion, and reduced interlayer fusion. The filament is therefore pre-dried in a vacuum dryer at 80 °C for 8–12 h or in a forced-air dryer at 80 °C for 12–24 h; the target moisture level is ≤0.10 mass% as verified by ISO 15512:2019 method A or B. Drying above 90 °C is not assumed acceptable for this white variant because the pigment and antioxidant package is not publicly specified. After drying, the spool is kept in a sealed dry box with desiccant and a feed-point dew point below −20 °C. Open-air exposure at 60% RH for 4 h can raise surface moisture enough to produce visible surface defects even when the nozzle setpoint is held within ±5 °C of target; moisture control is therefore a tighter operational boundary than hotend temperature control for this material.

Thermal and Rheological Boundary Conditions for Unfilled Polyamide 6 Filament

In an all-metal hotend with a 0.4 mm nozzle, unfilled PA6 filament is typically started at a setpoint of 250 °C and adjusted between 240 °C and 270 °C. The lower setpoint is established by the PA6 melting peak of 219–225 °C as measured by differential scanning calorimetry per ISO 11357-3:2018; the upper setpoint is bounded by thermo-oxidative yellowing of the white surface and molecular weight reduction during long residence above 270 °C. The build plate on a glass or polyetherimide surface is held at 70–90 °C; a setting of 100–110 °C is reserved for enclosure-equipped machines with a high-temperature bed. Chamber air temperature is controlled at 40–60 °C when the build volume exceeds approximately 150 mm in the longest axis. Capillary rheometry per ISO 11443:2021 is used to generate lot-specific flow curves; unfilled PA6 at 250 °C and 100 s⁻¹ commonly exhibits apparent viscosity in the order of 100–300 Pa·s, but the exact value depends on molecular weight, moisture, and white pigment concentrate. Published data for this specific Clariant white-filament configuration is limited; a lot-specific melt flow check using ISO 1133-1:2022 is required for process transfer between machines.

When Direct-Drive All-Metal Hotends Replace Bowden PTFE-Lined Systems

On a production-scale Cartesian platform with a direct-drive extruder and an all-metal hotend, the white PA6 filament is printable at 30–60 mm/s using layer heights of 0.15–0.25 mm. A Bowden PTFE-lined system introduces a long unsupported feed path; the filament can buckle between the drive gear and the heated zone because PA6 softens gradually above its glass transition. If a Bowden system is used, retraction travel is limited to 3.0–5.0 mm at 35–45 mm/s; direct-drive retraction is held at 0.8–1.5 mm at 25–35 mm/s. Part-cooling fan output is kept at 0–20% for the first five layers and no more than 30% thereafter. A high fan speed freezes the semicrystalline white surface, creates a skin-core boundary, lowers Z-direction strength, and increases edge curl. When the white pigment contains dispersed solids, a hardened-steel nozzle is not required for an unfilled grade, but the brass nozzle should be inspected after 200 h of continuous operation because titanium dioxide can be mildly abrasive; nozzle diameter is checked with a pin gauge rather than visual inspection alone.

Batch-to-batch variance in white PA6 filament appears first as a shift in melt viscosity and a shift in non-isothermal crystallisation onset. A lot with higher molecular weight may require an increase in nozzle setpoint from 245 °C to 260 °C; a lot with finer white pigment dispersion may nucleate crystallisation and raise the crystallisation onset temperature. On production-scale compounding lines, a twin-screw extruder with L/D 32:1 and a gear pump is used to disperse the white concentrate; screens and filter discs of 20–50 µm are typical after the melt pump. Under-dispersed pigment agglomerates above 10 µm can obstruct a 0.4 mm nozzle and appear as intermittent white specks or unmelted surface defects. Printed-part density is measured by Archimedes method per ISO 1183-1:2019 or by X-ray computed tomography; a void content above 3 vol% is considered a processing fault and is traced to wet feedstock, over-retraction, air entrapment from a leaking melt pool, or insufficient melt temperature.

Interlayer Adhesion, Print Speed, and Part Density Under Production-Scale Conditions

Mechanical performance of white PA6 printed parts is dominated by interlayer diffusion. With a chamber temperature of 45–60 °C and a nozzle temperature of 250 °C, Z-direction tensile strength can reach 70–90% of the in-plane value, but this ratio falls below 50% when the chamber is unheated, the part exceeds 200 mm in the longest direction, and the cooling fan exceeds 40%. Printed tensile specimens are prepared as type 1A bars according to ISO 527-2/1A and tested in both XY and Z orientations. A 0.4 mm nozzle at 0.2 mm layer height and 40 mm/s gives a volumetric throughput of 3.2 mm³/s; a 0.6 mm nozzle at 0.35 mm layer height and 50 mm/s gives 10.5 mm³/s. Residence time in the hotend should remain below 5 min at 260 °C to limit yellowing of the white surface and generation of volatile degradation products. With 1.75 mm filament, a high-viscosity PA6 lot above 300 Pa·s at 100 s⁻¹ may cause extruder motor stall on a 0.4 mm nozzle; switching to 2.85 mm filament reduces inlet buckling but requires recalibration of feed steps per millimetre and does not automatically resolve a melt-pressure limitation.

Critical Property Contrast with Glass-Filled PA6, PA12, and PETG in Fixture Fabrication

When compared with a 30 wt% short-glass-fiber-reinforced PA6, the unfilled Clariant white PA6 filament has a lower dry tensile modulus and lower heat deflection temperature. Unfilled PA6 at dry condition has tensile modulus in the range 2600–3300 MPa; a 30% glass-filled PA6 typically exceeds 6000–8000 MPa and shows higher melt viscosity and severe nozzle abrasion if printed through brass. The white unfilled grade is therefore not a substitute for glass-filled PA6 in highly loaded structural brackets but is machinable, tapable, and easier to recycle within a closed process loop. Compared with PA12, PA6 absorbs more water and develops higher strength and modulus; PA12 absorbs approximately 1.5–2.0 mass% at saturation, while PA6 absorbs 9.0–10.0 mass%. PA12 maintains better dimensional stability in humid end-use environments and has a lower melting peak near 175–180 °C, whereas PA6 melts near 220 °C. Compared with PETG, PA6 requires more aggressive pre-drying and a hotter bed, but it offers a higher continuous use temperature and higher creep resistance in warm oil environments; creep testing is performed under ISO 899-1:2017. The substitution of white PA6 for PETG is justified only when the printed fixture must handle warm oil wipe-down, creep loads above 70 °C, or both. It is not justified when the printing cell lacks a dryer and an enclosure.

What Standards Govern Batch Acceptance for White PA6 Filament?

Industrial purchase orders should require the following lot documentation: resin family PA6, white color designation, nominal filament diameter, measured ovality, net spool mass, drying condition, and melt flow rate. The acceptance plan is based on ISO 1133-1:2022 for melt mass-flow rate, ISO 1183-1:2019 for density, ISO 62:2008 for water absorption, ISO 527-2/1A for tensile properties of printed specimens, and ISO 11357-3:2018 for melting peak. RoHS compliance is assessed under Directive 2011/65/EU with amendment (EU) 2015/863; the restricted substances lead, mercury, hexavalent chromium, PBB, and PBDE are limited to 0.1 wt%, and cadmium is limited to 0.01 wt%. REACH compliance is governed by Regulation (EC) No 1907/2006; substances of very high concern on the candidate list must be declared if present above 0.1 wt%. For food-contact printed articles, nylon resins may be referenced under FDA 21 CFR 177.1500, but the final printed article requires migration testing because pigments, antioxidants, and surface roughness alter the extractable profile. A test report alone is not sufficient; the certificate of analysis must correlate to the spool batch.

Operational boundaries for the Clariant White Polyamide 6 3D Printer Filament are therefore defined by feedstock dryness, a heated or draft-free enclosure, low part-cooling airflow, and an all-metal hotend. The main field failure is moisture-related steam porosity, not temperature setpoint drift. This filament is considered a moisture-sensitive engineering thermoplastic and should not be treated as a general-purpose desktop material. Equipment compatibility is acceptable when a direct-drive extruder with a hardened all-metal thermal barrier and a glass or polyetherimide build plate is available; open-air Bowden systems with PTFE-lined hotends are not the preferred configuration above 245 °C unless the infeed is protected by a dry box and retraction is kept within the stated limits.