Method and device for production of three-dimensional objects by means of electromagnetic radiation and application of an absorber by means of an ink-jet method
View Patent ↗The present invention relates to a process for the bonding of material for the production of three-dimensional objects by selective heating with electromagnetic energy which is either non-coherent and/or non-monochromatic and/or non-oriented, with a wavelength of from 100 nm to 1 mm.
1. A process for producing a three-dimensional object, the process comparing:
a) providing a layer of a pulverulent substrate, wherein the pulverulent substrate is a powder material which is not coated, and wherein the pulverulent substrate comprises at least one homo- or copolymer selected from the group consisting of polyester, polyvinyl chloride, polyacetal, polypropylene, polyethylene, polystyrene, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polysulfone, polyarylene ether, polyurethane, thermoplastic elastomers, polylactides, polyoxyalkylenes, poly(N-methylmethacrylimides) (PMMI), polymethyl methacrylate (PMMA), ionomer, polyamide, copolyester, copolyamides, silicone polymers, terpolymers, acrylonitrile-butadiene-styrene copolymers (ABS), polyether sulfone, polyaryl sulfone, polyphenylene sulfide, polyaryl ether ketone, polyimide, polytetrafluoroethylene, and a mixture of these,
b) controlling the temperature of a manufacturing chamber by supplying heat to said layer to bring said layer to an elevated temperature or to maintain said layer at an elevated temperature below the melting or sintering temperature of the polymer in said pulverulent substrate,
c) selectively applying an absorber in a suspension or of a liquid absorber via an inkjet to at least one region of the layer to be sintered,
e) selectively melting the at least one region of the layer of the pulverulent substrate by applying electromagnetic energy emitted by a radiative heater in the IR-A region, and/or a radiative heater in the TR-B region, or emitted by a lamp in the visible region or a lamp in the IR-A region, and/or a lamp in the IR-B region,
f) cooling of the molten and non-molten regions obtained in e) to a temperature which allows formed moldings to be removed intact, and
g) removing the moldings intact, thereby obtaining the three-dimensional object,
wherein the selectively applying an absorber to the at least one region in c) includes raising the temperature of the at least one region by preheating the absorber to a temperature higher than the temperature of the at least one region and applying the preheated absorber to the at least one region.
2. The process as claimed in claim 1 , wherein e) is first carried out once, and then a) to c) are carried out once, and then b) is carried out and a) is carried out again once, and then the other steps are carried out in the sequence c), a), b), and e).
3. The process as claimed in claim 1 , wherein the pulverulent substrate has a median grain size of from 10 to 150 μm.
4. The process as claimed in claim 1 , wherein the electromagnetic energy is emitted by a radiative heater in the near or middle infrared region.
5. The process as claimed in claim 1 , wherein the electromagnetic energy is emitted by a lamp in the IR region or in the visible-light region.
6. The process as claimed in claim 1 , wherein the electromagnetic energy is emitted by an incandescent lamp.
7. The process as claimed in claim 1 , wherein the electromagnetic energy is emitted by a gas discharge lamp.
8. The process as claimed in claim 1 , wherein the electromagnetic energy from a source is emitted in a spot, linear, or spread form.
9. The process as claimed in claim 1 , wherein the absorber comprises at least one colorant.
10. The process as claimed in claim 9 , wherein the colorants comprise at least one pigment.
11. The process as claimed in claim 9 , wherein the colorants comprise at least one dye.
12. The process as claimed in claim 9 , wherein the absorber also comprises distilled water, at least one alcohol, or at least one other solvent.
13. The process as claimed in claim 9 , wherein the absorber also comprises at least one selected from the group consisting of a surfactant, a wetting agent, a biocide and a moisture retainer.
14. The process as claimed in claim 1 , wherein the absorber comprises at least one component selected from the group consisting of carbon black, CHP, animal, charcoal, graphite, carbon fibers, chalk, and at least one interference pigment.
15. The process as claimed in claim 1 , wherein the absorber comprises at least one component selected from the group consisting of carbon black, CHP, animal charcoal, graphite, carbon fibers, chalk, and at least one interference pigment.
16. The process as claimed in claim 1 , wherein the absorber comprises at least one flame retardant based on phosphorus or melamine cyanurate.
17. The process as claimed in claim 1 , wherein said pulverulent substrate further comprises from 0.05 to 5% by weight of a powder-flow aid.
18. The process as claimed in claim 1 , wherein said pulverulent substrate further comprises at least one inorganic fillers.
19. The process as claimed in claim 18 , wherein said inorganic filler comprises glass beads.
20. The process as claimed in claim 1 , wherein said pulverulent substrate further comprises at least one inorganic or organic pigment.