3D printing techniques were introduced in the 1980s with the aim to fabricate customized objects without the need for molds.
Since then, photopolymerization-based 3D printing techniques have attracted the interest of chemists, engineers and scientists.
So, what are photopolymers?
Photopolymers are typically thermoset materials that change properties when exposed to light to form cross-linked polymer structures.
With little finishing needed, photopolymer technologies can be specially formulated to accommodate unique application needs. To this end, the technology has opened opportunities in various fields.
Below, we explore three ways photopolymers are used in 3D printing.
1. Stereolithography (SLA)
Among different 3D printing techniques, stereolithography offers great directional uniformity in the final properties of materials. With the help of a precise UV laser, pre-programmed designs and shapes are drawn onto the surface of the vat of photopolymer.
Stereolithography uses UV light to propagate a polymerization reaction of the photocurable resins from liquids to solids. As the reaction continues a cross-linked polymer structure is created.
This process is repeated for each layer of the design or shape until the 3D object is complete.
2. Digital Light Processing (DLP)
Instead of laser light, a digital projector is used to display the image of the 3D object onto a tray of liquid polymer. When exposed to light, the photopolymer solidifies one layer at a time. This process is repeated until the 3D object is complete.
3. Continuous Liquid Interface Production (CLIP)
Continuous liquid interface production (CLIP) is another method of 3D printing that uses photopolymerization to create precise final products. Like the other methods, this technique can create a wide variety of shapes.
The process begins with a tray of liquid photopolymer resin. At the base of the resin tray is an oxygen-permeable window that creates a polymerization-free zone. This oxygenated region prevents resin from curing and adhering to the projection window.
Meanwhile, cross-sectional images of the object are projected in sequence from the UV light source underneath the resin tray, creating a physical object in continuous production.
SLA, DLP and CLIP enable fabrication of complex parts with desirable thermal, mechanical and optical properties.
Promerus develops a variety of electronic materials for the next generation of applications. These materials are based on high-purity polymers that provide outstanding electrical, mechanical, thermal and optical properties in many applications. To see what Promerus can do for you, contact us with questions.