E.i. Dupont De Nemours and Company

Olaf Thiele

Frank Zimmermann

Karsten Blatter

Armin Rettig

Method of repairing defective areas in a stoving lacquer coating, in which the defective area ready for repair lacquering is coated with a powder coating composition or with an aqueous powder coating slurry, and the applied powder coating is then melted and cured by irradiation with near infrared radiation (NIR).

Method for refinishing defects in stoved enamels with powder coatings

A process for preparing weather-resistant powder coatings on metallic or non-metallic surfaces by applying a powder coating composition and then melting and curing, wherein a powder coating composition is applied which contains polyester resins in which the acid structural blocks are based only or mainly on aromatic dicarboxylic acids, their anhydrides and/or esters, and polyfunctional low molecular weight epoxides as cross-linking agents, and the melting and curing is performed by NIR radiation.

Method for the production of weather-resistant powder coatings on a substrate

Process for curing powder lacquers by coating substrates with the powder lacquers and irradiating by radiation in the near infrared range (NIR radiation), which is characterized in that the curing times and/or the surface temperatures, obtainable by means of the radiation during certain curing times, of the substrates coated with the powder lacquers are controlled by setting the barium sulfate and/or aluminium oxide content of the powder lacquers to 1 to 50 wt. % and/or setting the carbon black content of the powder lacquers to 0.1 to 5 wt. %, the percentages by weight relating to the entire powder lacquer composition in each case.

Method for hardening powder coatings

Metal surfaces which are pre-treated with high-energy NIR-radiation and then coated with a powder or a liquid coating composition, followed by curing or drying the coating composition, show better adhesion to the coating and improved appearance and performance and the process is more cost effective.

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Baar-Ebenhausen, Germany

Olaf Thiele