Method of treating at least part of the surface of a 3D-printed article

A method of treating at least a part of a surface of an article comprising the steps of:

• I) providing the article at least a part of the surface of the article having been produced by an additive manufacturing method from a construction material, and the construction material provides a temperature TG′ at which the storage modulus G′ of the construction material (determined by dynamic-mechanical analysis according to ISO 6721 at a shear rate of 1/s) is 10 MPa, wherein the treating of at least a part of the surface comprises the action of pressure on the surface at a temperature of the surface above the temperature TG;′
• II) placing the article into an evacuable volume having a boundary comprising flexible sections intended for contact with the surface of the article, wherein the material for the boundary is selected such that it does not enter into any permanent bond with the construction material that has been heated above its
• temperature TG′ and then cooled below its temperature TG′;
• III) evacuating the volume, such that at least some of the flexible sections of the boundary of the volume come into contact with the surface of the article;
• IV) heating at least a portion of the surface of the article, while the volume still remains evacuated, for a predetermined period of time to a temperature above the temperature TG′;
• V) cooling the surface of the article to a temperature below the temperature TG′;
• VI) removing the article from the volume.