Essentium HTN-Z high temperature ESD nylon

Essentium is a US company with branches in Asia and Europe. They specialize in industrial 3D printers and technical filament. Their innovative material solutions are helping many companies enter the 4.0 industry by not only prototyping but also manufacturing on a large scale in-house, with quality and in a quick and affordable way. The Essentium catalog contains numerous cutting-edge technical filaments, mostly polymers and blends designed for exceptional strength, flexibility and high mechanical performance in challenging industrial settings. The Essentium filaments are used for many advanced purposes across numerous disciplines, for example in aerospace and defense, automotive, biomedical, contract manufacturing, consumer goods, and electronic manufacturing.

Technical filaments for specific uses

Essentium's HTN Z (High Temperature Nylon) filament is part of the manufacturer's vast material portfolio and belongs to the high temperature nylon (PA) family as well as the ESD Safe material category, the Z-brand. This filament is composed of > 90 % polyamide copolymer and MWCNT - Multi-walled carbon nanotube.

Video 1: A demonstration of the HTN Z ESD safety features. Source: Essentium.

Nylon (polyamide copolymer), is a synthetic semi-crystalline polymer created in the process of binding alternating diamine and dicarboxylic acid monomers. Nylon’s first commercial application was in making toothbrush bristles and women’s stockings in the 1930s. During WWII nylon was used to make parachutes, ropes, body armor and helmet liners for the US army. Nowaydays, nylon polymers have even more commercial applications, for example in the fabrics and fibers industry, molding in the automotive industry, or in the making of electronics and food packaging. Nylon is commonly used in 3D printing (as powder in SLS and MJF, or as pellets and filament in FDM) due to its qualities of durability, flexibility, resistance to abrasion, friction, corrosion and chemicals. Nylon is an extremely versatile thermoplastic and it is often used as a base for specialistic filament blends with various technical properties.

A high temperature filament

The thermal and mechanical properties of HTN Z have been significantly improved in comparison to standard nylon filaments in order to ensure high performance and high-temperature tolerance. HTN Z has a higher heat deflection temperature than regular nylons, it is tougher and stronger, more resistant to wear. Its chemical and solvent resistance have been boosted as well.

What’s more, the Essentium HTN Z is characterized by slow moisture absorption, which makes it easy to print and reduces the risk of warping. The manufacturer describes it as a drop-in replacement for Acetal, also a very strong and heat resistant engineering plastic.

ESD safe material

ESD (electrostatic discharge) is a phenomenon often experienced in everyday life in hair static or when a "kick" or "spark" of electricity is released upon touching a grounded object, for example a doorknob or even another person. Electrostatic discharge events such as these are harmless unless it happens on the manufacturing floor in industries where electronic components are handled. The Essentium HTN Z filament is the solution to that problem. It is destined for medium-duty electronics production. It acts as a dissipator of the ESD and lets the harmful discharge "evacuate" safely on the surface of a piece 3D printed with the HTN Z filament. ESD safe materials are also extremely useful in settings with potentially explosive atmospheres (petrochemical plants, coal mines, flour mills, areas with powder-based 3D printers).

Image 1: A circuit board rack, an assembly tray and a component enclosure (left to right) printed with the Essentium HTN Z. Source: Essentium.

Normally, to make a filament ESD safe, antistatic coatings or conductive fillers are added to the material. The most common fillers are carbon black and graphite. They can, however, have a negative impact on the performance of the filament or the 3D printed piece, making it brittle, causing it to leave a black mark like a pencil, or even cause latent failure in electronics. The Z line of filament is Essentium’s way to overcome those inhibitions produced by standard ESD filaments containing fillers. Instead, conductive nanomaterials are used on the surface of the filament, so the mechanical performance of pieces printed with HTN Z is not compromised. Since the percentage of carbon in this filament (around 0.01 %) is very low compared to other ESD filaments, which normally need to contain 20-30 % of carbon fiber to have enough surface resistivity, the overall cost of HTN Z is much lower than that of standard ESD filaments.

Thanks to those properties, the Essentium HTN Z can be used to 3D print jigs and fixtures for electronic device manufacturing (circuit board racks, assembly trays, component enclosures). The added benefit is that, being a high temperature nylon, the HTN Z can be safely used in high temperature surroundings, for example in wave soldering or in reflow ovens, and it will not melt or degrade easily. HTN Z can also be used to 3D print components that handle powders and pellets (they tend to cling to charged objects) or to make industrial equipment for spaces with combustible or explosive atmospheres.