Method for matching a colour formulation

US5929998A · kind A · utility

Assignee

• Herbert GmbH · DE

Inventors

• Wilhelm Kettler · Wuppertal, DE
• Matthias Kolb · Wuppertal, DE
• Albert Tacke · Wuppertal, DE

Key dates

• Filing date: Aug 21, 1997
• Grant date: Jul 27, 1999
• Expiry date: Aug 21, 2017

Classification

• Technology area (CPC G): Physics
• CPC primary: G01J3/504
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

This invention relates to a method for matching a color formulation to a color shade model in the field of a color- and/or effect-imparting surface coating. The reflecting surface of a color shade, which is to be rematched, of a colored surface coating is determined metrologically over the visible spectral region using a goniometric spectral photometer with variation of the angle of measurement. The associated standard tristimulus values and/or the vectors in the CIELAB color solid which are derived therefrom are calculated from the measured reflection factors or spectral energy factors. Those formulations and/or color shades which exhibit reflection properties or properties derived therefrom which are the most similar to the measured color shade model are subsequently identified from a formulation database by means of the reflection spectra or the calorimetric dimensional numbers derived therefrom. By means of a computer-generated effect matrix, the metrologically determined, angle-dependent color difference between the desired color shade, i.e. the color shade to be rematched, and the actual color shade, i.e. the color shade corresponding to the nearest formulation from the formu…