Material Jetting (MJ) speeds up the testing and go-to-market phase. It is used by a multitude of industries such as automakers, design firms, art studios or medical organisations to create reliable prototypes with a high level of accuracy. The process creates 3D prints with multiple material parts, colours and a smooth surface finish.

Material Jetting can be divided into several techniques, of which the most important ones are NanoParticle Jetting (NPJ) and Drop-On Demand (DOD). This article offers all relevant information on the Material Jetting process, materials used, advantages, drawbacks and how it can enhance the production processes of your organisation.

Material Jetting is a highly popular process, as it allows to integrate multiple material parts and colours in one single printing. This saves time and creates realistic prototypes. Material Jetting can be done in multiple ways, which are patented by different companies. The choice of the right process type mainly depends on your desired outcome.

Material jetting can be used for a combination of multiple materials. NanoParticle Jetting (NPJ) is the best option when you need to manufacture multiple small parts at once. Drop-On Demand (DOD) is the preferred choice of the jewelry industry. The following sections explain each type in detail.

The core material jetting technology, or PolyJet, used the very first printer by Object (later Stratasys). Material jetting technology jets ultra-thin layers of liquid photopolymer material onto the build tray, which can be compared to traditional inkjet printing. Each layer is immediately cured by UV light, so that the following layers can be built upon. Support materials can be used for complex geometries and are easily removed afterwards, either by hand or by water jetting. Material jetting parts can be a combination of rigid or flexible, colourful or clear materials, which may even be used for medical purposes. The 3D prints offer final product realism at granular detail.

Drop-On Demand (DOD)

The Drop-On Demand (DOD) process uses a wide range of materials such as wax instead of photopolymers. DOD printers have two print jets for build material as well as dissolvable support material. One big advantage of the system is its ability to print high resolution curves as well as a perfectly flat surface by skimming each completed layer with a fly cutter. This leads to precise and accurate results. The application is used by industries such as 3D printing for jewellery to create high-precision printing and molds.

NanoParticle Jetting (NPJ)

Nano Particle Jetting (NPJ) is an advanced 3D printing technology that is used to create complex and high-resolution objects by jetting tiny nanoparticles of material onto a build platform. It is a relatively new UV additive manufacturing technique that offers unique advantages in terms of precision, materials versatility, and resolution.

NPJ can work with a variety of materials, including metals, ceramics, polymers, and composites. Different jetting materials can be mixed together to create customized material properties for specific applications.

Material Jetting is a popular 3D printing process with a high level of accuracy, which makes it popular for highly realistic prototypes, injection moulds, investment castings and medical devices.

Designers can take advantage of Material Jetting’s multi-material, multi-colour capabilities, while the medical industry is able to produce anatomical models for surgical planning and training.

When it comes to low-volume moulds and patterns for certain industries, Material Jetting can even be a cost-efficient alternative to traditional tooling. However, next to its multiple advantages, Material Jetting does not suit all purposes. The following sections summarize the most important advantages of disadvantages that Material Jetting has to offer.

Disadvantages of Material Jetting

Despite its benefits, Material Jetting can be more expensive compared to other 3D printing techniques. The high cost of materials and equipment may not be suitable for low-budget projects. Additionally, achieving specific material properties can be challenging due to the viscosity limits of the resins used. This can result in weaker parts when compared to other methods like FDM or SLA, which may produce stronger, functional parts for specific industrial applications.

Advantages of Material Jetting

One of the biggest advantages of Material Jetting is the high level of resolution and accuracy. Each layer can be printed up to 0.013 mm, which leads to a smooth finish and accurate features. Support materials also don't leave marks after removal. The results are realistic objects, intricate shapes as well as sharp edges. Further, Material Jetting is able to layer many materials and colours, as printers can incorporate multiple nozzles. Depending on the goals, companies can achieve multiple properties such as translucency, opaqueness, rigidity or flexibility of the 3D print. Therefore, companies can create highly realistic prototypes, mould manufacturing, investment castings and even medical devices

Sustainability in Material Jetting Material

Jetting faces challenges in sustainability due to the difficulty of recycling photopolymers. However, ongoing research into biodegradable resins offers hope for a more sustainable future. Additionally, MJ’s precision reduces material waste compared to traditional manufacturing methods.

Waste Management and Recycling in Material Jetting

Proper disposal of photopolymer materials is essential to minimizing environmental harm. While some support materials are water-soluble, photopolymer resins are more complex and require specialized recycling processes. Efforts to recycle these materials are still in development, but the precise nature of MJ helps to minimize overall waste.

Material Jetting in Healthcare

In healthcare, Material Jetting is used to create highly accurate anatomical models for surgical planning, prosthetics, and dental appliances. Its ability to print with biocompatible materials makes it ideal for patient-specific solutions, allowing for custom-made devices and tools that improve patient outcomes.

Material Jetting in Aerospace and Automotive Industries

The aerospace and automotive sectors use Material Jetting for prototyping, tooling, and even low-volume production. The technology’s precision and ability to work with complex geometries make it an ideal choice for creating aerodynamic components, detailed dashboards, and other critical parts that require high accuracy and smooth finishes.

Ensuring Precision in Material Jetting

Quality control in Material Jetting involves close monitoring of the layer-by-layer printing process, ensuring that droplet deposition is accurate and consistent. High-resolution scanning and post-print inspection techniques are used to verify dimensional accuracy and surface finish.

Common Quality Issues and How to Address Them

Some common quality issues in Material Jetting include incomplete curing, layer shifting, and poor material adhesion. These issues can often be addressed by optimizing the material viscosity, adjusting the print speed, and ensuring that the UV curing system is functioning properly.

Emerging Applications of Material Jetting

One of the most exciting developments in Material Jetting is its use in creating multi-material and multi-color prints for consumer products, from wearable tech to custom jewelry. Additionally, the medical industry is exploring its potential for printing implantable devices using biocompatible materials.

Future Developments in Material Jetting Technology

The future of Material Jetting lies in improving material options, increasing printing speed, and reducing costs. Researchers are also exploring the possibility of using more sustainable, eco-friendly materials, which could make Material Jetting a greener technology.