3-D Printing Is Shaping The Future Of Packaging

By John Kalkowski, editor in chief, Food Online

In just a few years, 3-D printing has gone from a science-fiction vision to manufacturing reality in the packaging industry. The process gained its foothold as a design tool that was able to streamline prototyping. Now, it’s even being used to make finished packaging or tooling for packaging equipment.

With predictions that 3-D printing will have applications in food processing, who knows where it will go next? Perhaps the technology will be used to build packaging around the food that another 3-D printer just manufactured, making the entire system a printing process.

Also known as additive manufacturing, 3-D printing can employ various processes to make a three-dimensional object. The additive process lays down successive layers of material based on CAD designs that specify all the product’s dimensions in almost any shape or geometry.

The most common process in industrial 3-D printing is stereolithography (SLA), which employs liquid UV-curable photopolymer “resin” and an ultraviolet laser to build parts' layers one at a time. The laser traces a cross-section of the part pattern on the resin. Exposure to UV light solidifies the pattern and binds it to the layer below.

Another commonly used 3-D process is fused deposition modeling (FDM). In this process, the model or part is produced by extruding small flattened strings of molten material to form layers. The material hardens immediately after extrusion from the nozzle.

One thing is certain: The use of 3-D printing in packaging is growing quickly. A study by Smithers Pira estimates the overall global 3-D printing market, consisting of the combined value of the printers, polymer materials, parts and services, at $5.9 billion in 2015 across all industries. It’s predicted to grow to $49.1 billion by 2025, representing an annual growth rate of 23.7 percent.

Packagers Among 3-D Pioneers

Numerous packaging companies were among early adopters of the technology. I first saw the use of 3-D printing in the packaging design process nearly six years ago while visiting the research facilities of Tetra Pak in Lund, Sweden. An engineer who had worked with Tetra Pak told me that they had already been using 3-D printing for several years.

Within a short time, other packaging uses began cropping up. For instance, one manufacturer of molded fiber packaging says they were able to adapt the process to make the molds that shape the pulp around product to form protective trays for shipment. This gives manufacturers the ability to easily design the molds and print them in less time and at lower cost than a machined metal form. Because the polymer is a softer material than metal, the molds may have a more limited lifespan than metal forms, but still can be used for shorter runs.

The most common usage of 3-D printing in packaging is in the design process. In a recent presentation, Damien Moyal, senior design lead at ScorCreative, discussed how his group uses 3-D printing in their design process, saying it is typically used in the early, exploratory design stages as a fast and cost-effective way to glean insights. Producing quick prototypes eases internal vetting of the design and allows clients to test the hand-feel of the container. This creates a truer context as they make packaging decisions. In addition, designers can make fillable models that more accurately represent what the final product would look like, which can increase marketing buy-in earlier in the process.

Another big advantage is that 3-D printing creates a prototype as close to a production sample as possible. The printers can build samples at the true gram weights of planned containers. Some printers can even produce the samples with multiple colors that would be incorporated into the design. Moyal says this enables companies to evaluate performance and fine-tune products without committing to the time and expense of production tooling.

Finding New Materials To Use In Printing

Manufacturers are rapidly diversifying the materials that can be used in the printing process. Most are still thermoplastic polymers. These petroleum-based printing filaments are still used because they have a higher softening point and make more flexible models that will bend before they break. However, some companies, such as Biome3D, are formulating plant-based plastics because they are easier to work with during processing, and are food-safe and odor-free.

While most 3-D printers can only print one material at a time, a team of researchers at MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL) recently announced the  development of  the MultiFab 3D printer, which prints up to 10 different materials at once. This could allow a single printer to produce and finish a product with all its moving parts. The team also plans to experiment with embedding motors and actuators, making it possible to 3-D print more advanced electronics, such as servos and robots.

According to one industry survey, 70 percent of respondents believe that 3-D printing will soon be used to replace obsolete parts, and 57 percent believe it will be used for after-market parts.

There are technological limits to 3-D printing, such as the size of objects that can be built and the speed of the printing. These do not affect most current packaging applications, but do hinder its use in general manufacturing. However, as the technology advances, 3-D printing has a bright future in packaging and a seemingly limitless variety of applications.