Method for coating objects, in particular such objects that have been manufactured by a generative manufacturing method

1. Method for coating three-dimensional objects, which have been manufactured layerwise from a powder material by means of a generative manufacturing method, with a coating agent, wherein a binder-free coating is applied onto a surface of such three-dimensional object by blasting the surface with a blasting medium containing the coating agent

characterized in that

the objects to be coated were manufactured from a plastic powder as building material and in that the blasting medium contains said plastic powder that was used as building material

for manufacturing said objects to be coated.

2. Method according to claim 1 , in which a color powder, functional pigments, carbon black, graphite or pure color pigments or a combination thereof are used as coating agents.

3. Method according to claim 1 , wherein said plastic powder serves as coating agent substrate.

4. Method according to claim 1 , wherein powders, granules or balls are used as grainy blasting material in said blasting medium.

5. Method according to claim 1 , wherein in a further process step before the blasting process the surface of the three-dimensional object is roughened.

6. Method according to claim 1 , wherein in a further process step after the blasting process a surface sealing agent is applied onto the surface of the three dimensional object.

7. Method according to claim 1 , in which said generative manufacturing method, by which the object to be coated was manufactured, is a selective powder sintering method.

8. Method according to claim 1 , in which partial regions of the object are covered by one or more masks and in which several blast processes are carried out using blasting mediums that contain different coating agents.

9. Method according to claim 1 , in which said blasting medium contains a blasting material, wherein

the coating agent adheres to the surfaces of the grains of the blasting material.

10. Method according to claim 9 , in which said blasting medium furthermore contains a second blasting material, wherein said coating agent does not adhere to the surfaces of the grains of said second blasting material.

11. A method for applying a coating to an object which has been manufactured layerwise from a plastic powder by means of a generative (additive) manufacturing method, without the use of a binding agent applied to the object to adhere the coating, comprising the steps of:

providing a blasting medium which contains at least in part the same plastic powder used to make the object, the blasting medium further containing a coating material to be applied to the object; and

transferring the coating material to the object by blasting the surface of the object with the blasting medium to thereby mechanically transfer the coating material to the object in the absence of a binding agent.

12. The method of claim 11 , wherein the blasting medium contains a second blasting element different from the plastic powder.

13. The method of claim 12 , wherein the second blasting element also functions as a coating material to be applied to the object.

14. The method of claim 12 , wherein the second blasting element does not comprise a coating material to be applied to the object.