Process for partial colouring of plastic parts using solid colourants in colour- carrier layers

US12365775B2 · kind B2 · utility

Assignee

• Covestro Deutschland AG · DE

Inventors

• Georgios Tziovaras · Neuss, DE
• Heinz Pudleiner · Krefeld, DE
• Roland Kuenzel · Leverkusen, DE
• Florian Stempfle · Cologne, DE

Key dates

• Filing date: Apr 11, 2022
• Grant date: Jul 22, 2025
• Expiry date: Apr 11, 2042

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2369/00
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

The invention relates to a process for partial colouring, in particular colour laser engraving, of plastic parts, preferably of thermoplastic parts, very particularly preferably of thermoplastic parts comprising a layer construction, comprising the steps of: i) providing a plastic part (A) having at least one surface; ii) laying a colour tape atop at least one portion of the at least one surface of the plastic part (A) to obtain a surface of the plastic part (A) covered with the colour tape; iii) irradiating the plastic part (A) from ii) with focused, preferably nonionizing, electromagnetic radiation (C) on at least one portion of the surface of the plastic part (A) covered with the colour tape, wherein the partial colouring is effected essentially only at the sites on the plastic part (A) irradiated in step iii), wherein the wavelength range of the focused, preferably nonionizing, electromagnetic radiation (C) is in a range from 200 to 20 000 nm, preferably in a range from 300 to 18 000 nm, particularly preferably in a range from 350 to 16 000 nm.