In contrast to the dazzling shine of Silk PLA, there is Matte PLA – a filament designed to achieve a subtle, professional, and non-reflective finish. Its ability to masterfully conceal layers and create visually clean objects makes it a favorite for architectural models, product prototypes, and any prints where emphasis is placed on shape and form without distracting reflections. However, its mechanical properties are a subject of debate.
What is Matte PLA and how is its surface created?
Matte PLA is a specialized variant of PLA that achieves its matte effect by adding microscopic solid particles to the base polymer. These particles act as light diffusers – instead of light reflecting off the surface in an orderly fashion (which creates gloss), it is scattered in many directions. This eliminates gloss and simultaneously optically breaks up the sharp edges of individual print layers, making them less visible.
The most commonly used fillers are inorganic materials such as silica, talc, or even corn starch. Some manufacturers, such as Fiberlogy, emphasize the use of a high-quality PLA base (NatureWorks Ingeo™) to ensure consistent printing properties. There is also a variant called HTPLA (High Temperature PLA), which uses a mixture of plant fibers to achieve a matte surface and higher temperature resistance.
Advantages and Disadvantages
Matte PLA offers a unique aesthetic, which may, however, come at the cost of compromises in mechanical durability.
Advantages:
- Excellent aesthetics and layer hiding: The matte surface looks very professional and elegant. It effectively masks printing imperfections and layering, leading to visually cleaner models.
- Ideal for painting: The textured surface of matte PLA provides an excellent base for paint. It requires less preparation (filling and priming) than glossy plastics, as paint adheres better to it.
- No reflections: Suitable for product photography, architectural models, and parts where reflections are undesirable (e.g., camera housings).
Disadvantages:
- Potentially lower strength: Added fillers can disrupt the bonding between polymer chains and between individual layers, leading to lower strength and higher brittleness compared to standard PLA. However, this point is debatable (see below).
- Possible adhesion issues: Some users report poorer adhesion to the print bed, requiring more careful calibration and surface preparation.
How much does it cost?
In terms of price, Matte PLA is comparable to standard PLA, or slightly more expensive. A 1 kg spool typically sells for between 500–800 CZK.
Best temperatures and settings for printing
Printing with Matte PLA is generally very similar to printing with standard PLA and does not require any special hardware modifications.
- Nozzle temperature: The recommended range is typically 190–230 °C. It is advisable to print a temperature tower to find the optimal temperature that ensures the best matte effect and good layer adhesion.
- Bed temperature: Standard 50–70 °C. Due to occasional reports of poorer adhesion, it is crucial to have the print bed perfectly clean and the first layer correctly set.
- Speed and cooling: Standard profiles for PLA are a good starting point. Cooling should be at 100% to preserve details.
Reported problems: The strength debate
The mechanical strength of matte PLA is one of the most debated topics. There is conflicting evidence and experience, suggesting that properties can vary dramatically between different manufacturers.
On one hand, there is the theoretical premise and numerous user experiences claiming that matte PLA is weaker. The fillers that create the matte effect are essentially “impurities” in the polymer matrix. These particles can act as stress points and disrupt cohesion between layers, leading to lower strength and higher brittleness. Some sources quantify this theory – for example, one states that matte PLA has a flexural strength of approximately 53 MPa, while standard PLA reaches 76 MPa.
On the other hand, however, there are direct comparative tests that show the opposite result. In one documented test, where test bridges were broken under the same conditions, a print from Elegoo Matte PLA withstood a force of 41 N, while standard PLA from the same manufacturer broke at 37 N and their PLA+ at 39 N. Another manufacturer (Spectrum) even states “better tensile strength, flexibility, and long lifespan compared to classic PLA elements” for their matte PLA.
This discrepancy suggests that a blanket conclusion about the strength of “matte PLA” as such cannot be made. The resulting properties strongly depend on the specific brand, type and quantity of filler used, and the quality of the base PLA polymer. For the user, this means that if they want to use matte PLA for a functional part, they should not automatically assume its weakness, nor rely on its higher strength. The only reliable approach is to test the specific filament for the given application.
Ecological aspect
The presence of inorganic fillers such as talc or silica makes this material completely unsuitable for industrial composting. Like other composites, matte PLA belongs in mixed waste.
Surface treatment
One of the greatest advantages of matte PLA is its behavior during post-processing. The matte and slightly textured surface provides an ideal base for further modifications, especially painting.
- Sanding and filling: Although the matte surface hides layers well, sanding is still necessary for a perfectly smooth result. The process is the same as for standard PLA (ideally wet sanding).
- Painting: This is where matte PLA truly excels. Its surface has a natural “grip” (also known as tooth), which allows primer and paint to adhere much better than to the smooth and glossy surface of standard PLA. Fewer layers of filler and primer are often sufficient to achieve a uniformly covered surface, saving time and material.
