A little over a year ago, German materials engineer and inventor Kai Parthy introduced his novel Laywoo-D3 printing filament.

"This is a year in my life which I will not soon forget," Parthy said. "It wasn't easy to respond to all the inquiries from all over the world – and to raise production from small to large quantities due to demand."

As a follow up to his wood and plastic Laywoo-D3, Parthy also developed his Bendlay and Laybrick materials, but that's hardly the end of the story.

Now Parthy has introduced four new 3D printing materials, perhaps the most interesting of which he calls Poro-Lay. He says 3D printed objects built using Poro-Lay are filled with lots of... nothing.

To be completely accurate, PORO-LAY, which is compatible with all standard home 3D printers, is full of pores which allow it some unique properties.

What's the trick to how the material works? First, print an object with PORO-LAY, a stiff filament, then  rinse out the water soluble polymer component hidden and homogeneously dispersed inside the filament. A simple shaking of your 3D printed object as it's immersed in water (followed by sufficient drying time) and the object will be magically porous.

While the technical term for this process is 'extraction with solvent,' what you end up with is nothing short of fantastic – a 3D printed object which features properties like a soft rubber, very flexible object built around what he calls "micro-pores."

Lay-Tekkks flexible print

Aside from Poro-Lay, Parthy has also released Lay-Tekkks, a paperlike material which sports a fibrous surface.

Parthy says his new filaments are generally a blend of two main components, one is a functional component such as a rubber-like Elastomer, and the second is a soluble component like PVA, sugar, salt, or soluble resin. The parts are blended together, pelletized and extruded to a 3.0 mm or 1.7 mm filament.

"I can choose from a dozen different polymers for the mixture of A and B," Parthy says. "The resulting materials have different characteristics for a lot of applications. In general, all the new filaments have structure inside, some are more like a foam, with holes, others are more like a felt, with elongated, fibrous holes."

Parthy says another of his latest creations, Lay-Felt, contains stiff or soft felt fibers which are ideal for use as 3D membranes, semipermeable filters or even artificial paper. He says objects made from Lay-Tekkks are fibrous like felt, but with thinner, finer fibrous structures, and that this material is excellent for making oriented fibers, stacked fibers, cloth-like items and even tissues. His Lay-Fomm "feels like very soft rubber," and he says it's ideal for making micro-foam, sponges, bio-cells, elastics, and bendable suits.

Lay-Fomm magnified

Yet another version of his porous alchemy, a little something he calls Gel-Lay, is highly porous and results in "very unstable" printed output. Parthy says he can see it being used for objects in water, marine organism flow simulation and biomechanics studies.