Unlocking “Soft Power”! All About eSUN’s Flexible 3D Printing Materials and Applications

In recent years, flexible 3D printing materials have become an important choice in industrial manufacturing, medical, and consumer electronics fields due to their excellent ductility, impact resistance, and wear resistance.

The accelerating process of “desktop industrialization” will further promote the popularization of distributed manufacturing and personalized production, while accelerating the application and development of flexible 3D printing materials in people’s production and daily life.

eSUN’s flexible material portfolio includes a wide range of TPU and TPE materials, such as TPU-95A, TPU-90A, TPU-87A, TPU-85A, TPE-83A, TPU-64D, TPU-HS , TPU-LW , TPU-Temp Color Change , etc.

Applications of Flexible 3D Printing Materials

1.Custom Prosthetics and Orthotics

The customization advantages of 3D printing make it particularly suitable for medical and rehabilitation applications.

Prosthetics, prosthetic liners, or insoles printed with TPU materials can better fit human curves, offering good elasticity and comfortable touch, making them ideal for wear.

TPU materials can also be used to manufacture dynamic orthotics, achieving intelligent mechanical adaptation during rehabilitation through variable-stiffness 3D printing structures.

2. Industrial Manufacturing: Shock-Absorbing Components and Seals

In industrial manufacturing, flexible 3D printing materials can be used to produce shock-absorbing pads, sealing rings, and protective covers.

For example, in the field of smart robots, bio-inspired tentacles printed with soft TPU materials can achieve a bending radius of <2mm, precise grasping force control of 0.1-5N, and a surface microstructure with an anti-slip coefficient of μ>1.2.

Additionally, flexible materials can be used for batch production of flexible fixtures and industrial seals.

3. Consumer Electronics: Impact-Resistant Cases and Flexible Accessories

Thanks to the flexibility and impact resistance of TPU materials, they are widely used in customizing flexible protective cases and impact-resistant components.

For example, eSUN’s U.S. customers use TPU materials to make supports and protective gear for electric unicycles, which provide both hardness and comfort.

TPU can also be used to print parts fixed on electric vehicle bumpers to absorb impacts, reducing or preventing bumper damage and personal injury.

4. Fashion and Footwear: Custom Soles and Athletic Shoes

The development of 3D printing in fashion and wearable fields is accelerating.

Using flexible 3D printing technology, users can create athletic shoes, sandals, backpacks, clothing, and watch straps.

For footwear applications, 3D-printed high-performance running shoes with honeycomb structures enhance rebound while reducing overall weight.

New eSUN Flexible 3D Printing Materials

Recently, eSUN will launch three new materials: TPU-90A, TPU-85A, and TPU-64D.

These materials offer excellent durability and wear resistance, making them suitable for shock absorption and soft-support models. They also support hybrid rapid manufacturing (combining soft and hard materials) on devices like Bambu Lab H2D.

1.TPU-90A

TPU-90A combines flexible touch with high hardness, offering outstanding durability and wear resistance. It is ideal for footwear and tires that require both flexibility and strength.

2. TPU-85A

TPU-85A is softer than TPU-95A and TPU-90A, making it suitable for printing shock-absorbing models or components, such as protective covers and cushioning parts.

Application Example: Tennis racket dampeners

3. TPU-64D

eSUN’s TPU-64D uses a special modification method to lower processing temperatures, improve low-temperature plasticity, and enhance surface smoothness.

It has high hardness and lower printing temperature requirements, improving printability.

In practical applications, TPU-64D can be used for footwear or cushioning protective components.

For example, 3D-printed sports shoe soles made with TPU-64D offer 300% better wear resistance than traditional rubber and meet high-intensity impact resistance requirements. Optimized structural design can also reduce weight by 30%.

Helmets with honeycomb-truss composite structures 3D-printed with TPU-64D achieve an energy absorption density of 35kJ/m³, five times higher than traditional EPS materials, and can incorporate active cooling channels for better impact protection and overall user experience.

Printing Tips for Flexible Materials

The launch of the Bambu Lab H2D device provides a “convenient pathway” for hybrid manufacturing with flexible materials. However, the following points should be noted for printing:

Equipment:

1 It is recommended to use a direct-drive extruder (short-distance extruder). Materials with hardness above 85A have specific requirements for the throat tube and extruder gears: the throat tube should not be too long, and the extruder gears need higher gripping force.

2. Nozzle: A 0.4mm or larger nozzle is recommended.

3. Print bed: A standard PEI or glass bed is recommended. TPU materials have good bed adhesion, so high bed temperatures are unnecessary.

Print Parameter Settings

1.Printing temperature: 200-250°C. Different hardness materials may require different settings on different printers. For example, 64D and 95A typically print well at 220°C, while higher temperatures may cause bubbling. Softer materials like 90A and 85A are harder to extrude at lower temperatures, so a temperature of around 240°C is recommended.

2. Flow rate: 1.0-1.05 is recommended. TPU materials tend to under-extrude, leading to layer separation in model walls. Increasing the flow rate slightly can improve wall adhesion.

3. Retraction: Reduce or disable retraction. Excessive or frequent retraction can cause deformation at the extruder gears.

Other Considerations：

1.Drying: TPU materials are highly hygroscopic and prone to moisture absorption. Drying before printing is recommended.

2. Spool holder: For softer materials like 83A and 85A, placing the spool too far away may cause feeding difficulties. Optimize the spool holder position based on actual printing experience.

Hybrid Printing with Soft and Hard Materials

The innovation and application of flexible 3D printing materials are driving transformative changes in manufacturing, offering more efficient and personalized solutions across industries.

With continuous breakthroughs in material technology, their applications will expand further, unlocking more possibilities for smart manufacturing, healthcare, consumer electronics, and beyond.