Poylmeric composition for use as a temporary support material in extrusion based additive manufacturing

Abstract

The polymeric composition of this invention can be used as a temporary support material in the additive manufacturing of three dimensional articles without compromising the quality of the ultimate product, reducing printing speed, increasing cost, increasing the incidence of printer jamming, or requiring printers of increased complexity. This invention more specifically discloses a polymeric composition which is particularly useful as a temporary support material for utilization in three-dimensional printing, said polymeric composition being comprised of a first polymeric component which is suitable for use as a modeling material and a second polymeric component which is immiscible with the first polymeric component, wherein the polymeric composition has a continuous phase, wherein the continuous phase is comprised of the second polymeric component, and wherein the polymeric composition has a Shore A hardness of at least 80.

Description

[0001]This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62 / 047,723, filed on Sep. 9, 2014. The teachings of U.S. Provisional Patent Application Ser. No. 62 / 047,723 are incorporated herein by reference in their entirety.BACKGROUND OF THE INVENTION[0002]By definition, “rapid prototyping” is a group of techniques that can be used to quickly fabricate a scale model of a physical part or assembly using 3-dimensional computer aided design (CAD) data. In rapid prototyping, construction of the part or assembly is usually done in an additive, layer-by-layer fashion. Those techniques that involve fabricating parts or assemblies in an additive or layer-by-layer fashion are termed “additive manufacturing” (AM), as opposed to traditional manufacturing methods which are mostly reductive in nature. Additive manufacturing is commonly referred to by the general public as “3D printing”.[0003]According to ASTM Committee F42 on Additive Manufacturing Technologies, ther...

AI Technical Summary

Benefits of technology

This invention provides a polymeric material that can be used as a temporary support material in 3D printing. It can be easily removed by simple mechanical means and is long-lasting before being used. It does not absorb any water and is safe to use. Additionally, it can be used in the additive manufacturing of 3D articles without compromising the quality of the final product, reducing printing speed, increasing cost, or requiring complex printers.

Problems solved by technology

Furthermore, the generation of potentially toxic degradation products during printing makes ABS a less suitable option for desktop 3D printers because such printers generally do not have a heated build envelope and an effective mechanism to eliminate the odor and toxic degradation products.

However, PLA still suffers from a number of drawbacks, including poor impact strength and a low softening temperature.

The low softening temperature leads to difficulties with extrusion and printing quality.

However removing the temporary support structure in such cases can be very challenging because the adhesion between the support structure and the model is often too strong.

In any case, removing the temporary support structure requires extensive labor and can often lead to poor surface appearance and even mechanical damage to the part being made.

However, a significant drawback associated with utilizing of this class of temporary support materials is the difficulty to preserve them because they typically absorb large amounts of moisture from the atmosphere.

The absorbed water can then change the physical dimension of the material (usually used in a filament form) as well as its thermal and rheological properties which can lead to printing problems, such as incorrect feeding and even printer jam.

Accordingly, support materials in this class often have relatively short shelf lives and need to be used quickly once the material is opened from the packaging and exposed to the air.

First, relatively large amounts of organic solvents are typically required to remove the support structure, leading to added cost and handling difficulties.

Some organic solvents which can potentially be used are flammable, toxic to humans and animals, and / or have an adverse effect on the environment.

Finally, the solvent waste (with support material dissolved in it) may require special disposal, which further leads to added cost, complexity, and environmental impact.

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