3D Printing InfoFilament comparison
Conductive vs TPU soft
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | Conductive filamentSPECIALTY | Soft TPU (below 85A)FLEX |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | $170.36/kg median; $89.99–$796.00/kg across 4 dated product listings | $114.04/kg median; $109.80–$122.27/kg across 4 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | A carbon-filled compound conductive by volume rather than merely dissipative; Proto-pasta's is PLA-based, Recreus's and NinjaTek's are TPU, and add:north's Koltron G1 does not state its base polymer[1][2][3][4] | Very soft thermoplastic elastomers below 85 Shore A. Fiberlogy's FiberFlex 30D measures 81 Shore A, the softest grade with a published datasheet found here[5] |
| Densityg/cm³ | Not documented | 1.07 (Fiberlogy FiberFlex 30D, ISO 1183)[5] |
| Typical priceUSD/kg | 1 kg-equivalent spools span 90–181 for the carbon-filled grades; add:north's Koltron G1 sits far above at 796 because it is sold only in 100 and 250 g coils[6][7][8] | 1 kg-equivalent spools cluster near 115[2][9][10] |
| Price range across brandsUSD/kg | 90–796 across brands; Proto-pasta conductive PLA 90 at 1 kg, Recreus Conductive Filaflex 160 at 500 g, NinjaTek Eel 181 at 1 kg, add:north Koltron G1 796 at 250 g[6][2][7][8] | 110–122 at 1 kg-equivalent; Recreus 70A 110 and 60A 116 at 500 g, NinjaTek Edge 83A 112, NinjaTek Chinchilla 75A 122; the Recreus 3 kg spools fall to 70–73[2][10][9] |
| Market availability1–5 | Niche, a handful of specialist brands[6][2] | Niche, a handful of specialist brands[5][11][2] |
| Spool sizes & diameters | 1.75 and 2.85 mm; 0.05, 0.1, 0.25, 0.5, 1 and 2 kg spools[6][2][7][8] | 1.75, 2.85 and 3 mm; 0.5, 0.85, 1, 2 and 3 kg spools[5][2][12][9] |
| Typical applications | Capacitive touch surfaces, low-current traces, EMI shielding and static-safe fixtures[1] | Highly compliant seals, soft grips and prosthetic liners[5] |
| Printing Parameters | ||
| Bed temperature°C | Not documented | 50–70 (Fiberlogy FiberFlex 30D)[5] |
| Enclosure / chamber requirement1–5 | Open frame is fine[1] | Open frame is fine[5] |
| Bed surface & adhesion aid | Not documented | PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[13][14] |
| Overall printing difficulty1–5 | Intermediate — dry filament and a tuned profile[1] | Expert / industrial hardware only — below 85 Shore A the filament buckles in almost any feed path that is not a short, constrained direct drive[12][14] |
| Extruder requirement | Not documented | Direct drive only, with a constrained filament path; Bowden is not viable at this hardness[12][11] |
| Hardware Wear & Reliability | ||
| Nozzle hardness required1–4 | Brass acceptable; hardened steel for volume work[1] | Brass fine indefinitely[15] |
| Abrasiveness1–5 | Moderately abrasive — conductive carbon filler[1] | Non-abrasive[15] |
| Nozzle clog risk1–5 | Low — Proto-pasta states the carbon-filled grade prints on standard PLA settings with no special nozzle required[1] | High — jams from moisture, heat creep or particles; below 85 Shore A the filament buckles and compresses, and Simplify3D warns that raised feed rates most likely end in a jam[13][14][16] |
| Heat-creep / jam sensitivity1–5 | Not documented | Very high — softens in the cold zone readily[14] |
| Hotend requirement | Not documented | No special hot-end required, but a direct-drive extruder is (Simplify3D)[13] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Not documented | Moderate[16] |
| Symptoms when wet | Not documented | Bubbling and popping at the nozzle, stringing and a rough surface[16] |
| Effect of moisture on strength | Polymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[16] | Polymaker groups TPU with the highly hygroscopic materials; no dry-versus-conditioned figures are published[16] |
| Storage requirement | Not documented | Sealed with desiccant; often kept in a dryer during the print[16] |
| Mechanical Properties | ||
| Elongation at break% | Not documented | 870 at break (Fiberlogy FiberFlex 30D, ISO 527) — the highest elongation in the dataset[5] |
| Brittleness1–5 | Brittle — snaps with little warning; carbon-black loading at conductive levels embrittles PLA[1] | Very ductile — bends far before failing[5] |
| Hardness (scale-specific)Shore A / Shore D / Rockwell | Not documented | 81 Shore A and 30 Shore D (Fiberlogy FiberFlex 30D, ISO 7619)[5] |
| Creep resistance / sustained load1–5 | Not documented | Poor — no creep test at this hardness; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg[17] |
| Fatigue / repeated-flex resistance1–5 | Not documented | Excellent — living hinges viable[14] |
| Elasticity / flexibility1–5 | Rigid[1] | Rubbery / highly elastic[5] |
| Wear resistance & friction | Not documented | Tear strength 95 kN/m (Fiberlogy FiberFlex 30D, ISO 34-1)[5] |
| Thermal Properties | ||
| Melting point / Vicat°C | Not documented | 170 melting (Fiberlogy FiberFlex 30D, DSC)[5] |
| Environment & Chemical | ||
| UV resistance1–5 | Not documented | Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[14] |
| Chemical resistance | Not documented | Withstands industrial solvents and UV exposure (Polymaker)[14] |
| Food contact | Not documented | Not food safe without specific certification (Polymaker)[14] |
| Biodegradability / compostability | Not documented | Not biodegradable[14] |
| Recyclability | Not documented | Not accepted in household plastic collection[14] |
| Electrical & ESD properties | Conductive rather than dissipative — Proto-pasta sells the grade as electrically conductive composite PLA[1] | Not documented |
| Health & Safety | ||
| Fume toxicity1–5 | Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[18] | Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[18] |
| Ventilation / filtration requirement1–5 | Open a window / occasional ventilation[18] | Open a window / occasional ventilation[18] |
| Dust & fibre handling hazard | Conductive carbon filler is bound in the matrix; avoid inhaling sanding dust[1] | Not documented |
| Post-Processing | ||
| Sanding & machining | Not documented | Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[14] |
| Gluing & solvent welding | Not documented | Cyanoacrylate bonds TPU; no common solvent welds it[14] |
| Vapour / chemical smoothing | Not documented | No practical vapour smoothing[14] |
| Support material pairing | Not documented | Polymaker warns TPU supports are often very difficult to remove[14] |
| Solvents & Solubility | ||
| Soluble in | Chloroform dissolves PLA-based grades, leaving the carbon black; TPU-based grades need DMF, NMP or THF. Laboratory reagents.[19][20] | DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[20] |
| Softened or crazed by | Acetone and ethyl acetate plasticise a PLA-based grade; a TPU-based grade swells in toluene, esters and alcohols.[19][20] | Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[20] |
| Solvent welding & smoothing agent | None — neither PLA nor TPU has a workshop-safe welding or smoothing solvent.[19][20] | None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[20] |
Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.
Sources for this comparison
- Electrically Conductive Composite PLA — product page and technical data Proto-pasta · 2026-08 · tds
- Recreus product catalogue Recreus · 2026-08 · vendor
- Eel 3D Printing Filament Technical Specifications NinjaTek · 2026-08 · tds
- Koltron G1 Technical Data Sheet add:north · 2026-08 · tds
- FiberFlex 30D Technical Data Sheet Fiberlogy · 2026-08 · tds
- Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
- Eel product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
- add:north Koltron G1 product page add:north · 2026-08 · vendor
- Chinchilla product page — print guidelines, spool sizes and price NinjaTek · 2026-08 · vendor
- NinjaFlex Edge product page — durometer, print guidelines and price NinjaTek · 2026-08 · vendor
- Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
- NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
- Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
- TPU — material basics Polymaker Wiki · 2026-08 · doc
- Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
- Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
- Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
- Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds