| 摘要 |
The invention relates to an article having a surface covered with a group of magnetically oriented particles (1), each particle having first (14) and second (15) regions, preferably opposite one another, that have different optical properties. According to the invention, at least a portion of the particles (1) are substantially all oriented with the first region (14) turned towards the surface, said portion being located in an area covering at least 1 mm2 of the article, the particles being fixed with a pre-defined orientation. |
