The present disclosure relates to a 3D printer for construction for printing and forming various structures, in which agitating blades 45 capable of auto-rotation are mounted inside a nozzle 10 discharging a printing material such as concrete or mortar, to thereby enable agitation of a fluid printing material inside the nozzle 10. According to the present disclosure, agitation of the fluid printing material inside the nozzle 10 of the 3D printer for construction may be facilitated to prevent material segregation and maintain a homogeneously mixed state of materials constituting the fluid printing material.

A homogeneous extruded mold release composition including: less than 5 wt % of water; 30 to 80 wt % of a polyvinyl alcohol; 2 to 4 wt % of a surfactant; 10 to 40 wt % of a sugar alcohol; and 0.75 to 3.0 wt % of an anti-foaming agent; where a total of all components in the composition adds to 100 wt %. The extruded mold release composition has a solution surface tension of 24 mN/m or lower and a viscosity in a range from 80 to 300 cps when measured at 23 C. after the composition has been solubilized in water to produce a 15% to 18% by weight solution.

A homogeneous extruded mold release composition including: less than 5 wt % of water; 30 to 80 wt % of a polyvinyl alcohol; 2 to 4 wt % of a surfactant; 10 to 40 wt % of a sugar alcohol; and 0.75 to 3.0 wt % of an anti-foaming agent; where a total of all components in the composition adds to 100 wt %. The extruded mold release composition has a solution surface tension of 24 mN/m or lower and a viscosity in a range from 80 to 300 cps when measured at 23 C. after the composition has been solubilized in water to produce a 15% to 18% by weight solution.

A method of producing a freestanding ceramic tile. The method involves: grit-blasting a substrate using a grit size in the range from 36 to 220 mesh; depositing a release layer of carbon or graphite from 2 to 10 microns thick on the grit-blasted surface of the substrate; applying ceramic over the release layer until a desired thickness of ceramic is achieved to form a ceramic layer; heating the substrate, release layer, and ceramic layer to a temperature of from 800 to 1000 degrees Celsius; keeping the substrate, release layer, and ceramic layer at a temperature from 800 to 1000 degrees Celsius for a time from 10 to 20 minutes to remove the release layer; and cooling the substrate and ceramic layer at a rate of at least 200 degrees Celsius per minute, such that the ceramic layer separates from the substrate to produce a freestanding ceramic tile.

The invention relates to a casting mold, in particular for use in cold casting methods, which is produced with the aid of a powder-based layering method, the final casting mold having a treated surface.

The invention relates to a casting mold, in particular for use in cold casting methods, which is produced with the aid of a powder-based layering method, the final casting mold having a treated surface.