The Evolution of SLA/DLP Materials in Additive Manufacturing

1. Introduction:

In the first part of this white paper, we established that SLA and DLP printing technologies have evolved into a dominant force in additive manufacturing (AM). Unlike traditional fused deposition modeling (FDM) or powder-bed fusion (PBF) methods, these resin-based technologies offer rapid material switching, high-speed printing, and superior surface quality. More importantly, recent advancements in photopolymer chemistry have addressed the historical limitations of resins, enabling them to rival traditional thermoplastics in both mechanical and thermal performance.

EnvisionTEC, a leader in industrial-grade SLA/DLP materials, has developed a comprehensive library of high-performance resins that push the boundaries of AM. These materials are formulated to meet the demands of aerospace, medical, automotive, and industrial applications, covering a wide range of mechanical properties from ultra-rigid thermoplastic replacements to flexible elastomers and high-temperature-resistant composites.

This section categorizes EnvisionTEC’s high-end resins into four primary groups:

• Hard Plastics: Rigid, durable resins mimicking materials such as ABS, polycarbonate (PC), and glass-filled nylon.
• High-Temperature Resins: Heat-resistant and flame-retardant materials designed for demanding applications.
• Elastomers: Flexible, rubber-like resins with properties comparable to TPU and silicone.
• Castable Resins: High-wax-content resins optimized for investment casting in jewelry, dental, and industrial applications.

By breaking down the mechanical properties and applications of each resin, this article makes a clear case for SLA/DLP printing as a viable alternative to injection molding, powder-based AM, and conventional polymer manufacturing.

2. Hard Plastic Resins: Rigid and Durable Thermoplastic Alternatives

Hard plastic resins are designed for industrial-strength applications that require high rigidity, impact resistance, and excellent mechanical performance. These materials offer properties comparable to conventional thermoplastics like ABS, polypropylene (PP), and glass-filled nylon, making them ideal for functional prototypes, end-use parts, and industrial tooling.

Key Properties and Comparisons

Material Descriptions

2.1 E-RigidForm: High-Stiffness Polyurethane Alternative

E-RigidForm is a high-performance rigid resin designed for industrial and consumer applications. Its high modulus and excellent tensile strength make it an ideal alternative to polyurethane-based thermoplastics. The material provides a superior surface finish and maintains dimensional stability over time, making it useful for housings, rigid enclosures, and structural parts exposed to mechanical loads.

2.2 Loctite E-3843: Industrial ABS-Like Resin

Loctite E-3843 is a high-modulus, impact-resistant material designed for functional prototyping and end-use parts. Its combination of high elongation at break (47%) and good thermal stability makes it suitable for load-bearing applications in industries like automotive and consumer electronics.

2.3 Loctite IND 405: Polypropylene Replacement

Loctite IND 405 provides excellent impact strength and elongation, closely mimicking polypropylene’s performance. It is ideal for applications requiring flexibility and toughness, such as lightweight jigs, fixtures, and high-production tooling.

2.4 E-GFP: High-Strength Glass-Filled Resin

E-GFP offers one of the highest tensile strengths among EnvisionTEC resins, making it an excellent substitute for glass-filled nylon in applications requiring rigidity and heat resistance. It is commonly used for electrical connectors, manufacturing jigs, and alignment fixtures.

3. High-Temperature Resins: Thermal and Flame-Resistant Materials

High-temperature resins are designed for extreme environments where parts must withstand high thermal loads, flame exposure, or continuous mechanical stress at elevated temperatures. These resins are commonly used in aerospace, automotive, and industrial applications where traditional polymers would deform or degrade.

Key Properties and Comparisons

Material Descriptions

3.1 E-Perform: High-Stiffness Ceramic-Filled Resin

E-Perform is a ceramic-filled high-temperature resin with exceptional compressive strength and wear resistance. It is ideal for short-run injection molds, high-temperature testing components, and wind tunnel parts.

3.2 Loctite IND406: Industrial High-Temperature Resin

Loctite IND406 is a durable, tough material that balances high-temperature resistance with good mechanical properties. It is an excellent alternative to traditional injection-molded ABS and PP for end-use automotive and industrial applications.

3.3 Loctite 3955 HDT280 FST: Aerospace and Rail-Approved Resin

Designed for extreme environments, Loctite 3955 meets UL94 V-0 and Airbus FST requirements. With a heat deflection temperature of 300°C, it is used in aerospace and rail applications where flame resistance and mechanical stability are critical.

4. Elastomers: Flexible, Rubber-Like Resins

Elastomeric resins provide superior flexibility, durability, and impact resistance, making them ideal for soft-touch applications, gaskets, and medical wearables.

Key Properties and Comparisons

5. Castable Resins: High-Wax Content for Investment Casting

Castable resins allow for clean burnout and are optimized for lost-wax casting processes in jewelry, dental, and industrial applications.

6. Conclusion: SLA/DLP as a Viable Alternative to Injection Molding

With EnvisionTEC’s advanced resins, SLA/DLP printing has moved beyond prototyping into full-scale production. These materials offer a combination of mechanical performance, thermal resistance, and flexibility that rival traditional manufacturing processes, making SLA/DLP the most versatile AM technology available today.

For more information, visit RapidMade.