Method for producing a powder comprising at least one polymer and such a type of powder

US12365115B2 · kind B2 · utility

Assignee

• EOS GmbH Electro Optical Systems · DE

Inventors

• Andreas Pfister · Munich, DE
• Mandy Gersch · Ulm, DE
• Daniel Froehlich · Gräfelfing, DE
• Verena Galitz · Krailling, DE
• Sybille Fischer · Eichenau, DE

Key dates

• Filing date: Apr 23, 2019
• Grant date: Jul 22, 2025
• Expiry date: Jan 27, 2040

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29K2077/00
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A method for producing a powder comprising at least one polymer for use in a method for the additive manufacture of a three-dimensional object is described. The method includes the step of mechanically treating the powder in a mixer with at least one rotating mixing blade, wherein the powder is exposed to a temperature TB and TB is at least 30° C. and is below the melting point Tm of the polymer (determined according to DIN EN ISO 11357) if the polymer is a semi-crystalline polymer, or wherein TB is at least 30° C. and wherein TB is at most 50° C. above the glass transition temperature Tg of the polymer (determined according to DIN EN ISO 11357) if the polymer is a melt-amorphous polymer. Compared to a time before the start of the treatment, it may be achieved that after the treatment, the bulk density of the powder is increased by at least 10% (or in the case of polymer, copolymer or polymer blend of polyamide at least 2% and more) and the BET surface area is decreased by at least 10%, and optionally also the pourability is improved by at least 10%.