MCAD 3D Printing and Prototyping: Multicolor 3D Printing: Fact vs. Fiction

Today’s guest post is from Joe Titlow, VP of Product Management at Z Corporation.

Z Corporation invented color 3D printing over 10 years ago and continues to be the only 3D printer manufacturer to offer true color 3D printing. Interestingly though, some other printers on the market have begun to talk about their ‘color capabilities’ as well. And while we appreciate the reinforcement that being able to 3D print in color is valuable and important, it occurred to me that people might not understand the technical differences between the various 3D printing technologies with regard to color capabilities. So to better educate everyone, I thought I would outline the technical differences and then the color-related applications are appropriate for the various technologies.

Most 3D printing and rapid prototyping technologies (SLA, SLS, DLP, etc.) work in ‘monochrome,’ where only one color is used and that color is the base color of the material. There are a few technologies that claim ‘color’ 3D printing, but the definition of what it means to print in ‘color’ differs wildly between vendors. As far as I know, there are three companies that claim to offer color 3D printing:

- Stratasys/uPrint (HP in Europe): the uPrint Plus is marketed as a 'color 3D printer' because it can produce color parts in eight different colors. However, this can only be accomplished one color at a time, as switching between one color and another requires the operator to manually switch the printer’s input plastic reel. The only way these printers can produce 'multicolor' parts is if the operator manually assembles the separate monochrome parts after they are printed. This is similar to printing individual pieces of paper on a document printer, each with one color, and then gluing them together afterward to form a multicolor picture. It’s laborious, time consuming, and the colors produced are very limited.

- Objet Connex 3D Printers: The Connex printers from Objet, as a byproduct of their ability to print different resins at the same time, are able to produce a handful of colors. The maximum number of unique colors available in one build is 11 (all shades of gray) and this is accomplished by mixing a white resin and a black resin for large sections of a part. These printers cannot address pixel-level color variation - only 'shells' of model (or large sections of the design). They also cannot accept color files into their software – the colors (or really the materials) are assigned manually during the process by the operator.

- Z Corporation has a range of multicolor-capable 3D printers, ZPrinters, that produce color by mixing the fundamental primary colors of Cyan, Magenta, Yellow, Black and White together. This is done on the fly, automatically during printing and results in 390,000 unique color combinations. This enables true color printing in any color that the customer desires. Since ZPrinters create these unique colors at the pixel level, detailed texture maps can be used to simulate the appearance of various materials, add logos, and basically build any image into a prototype that might be desired. The result here is some incredibly life-like models that other 3D printing technology simply can’t produce:

The following chart highlights these technical differences and indicates which color applications are feasible among the three different 3D printing technologies: