Inorganic sheet carrying symbols for making pigments
AssigneeSicpa Holding SA
InventorsEdgar Müller, Olivier Rozumek, Anton Bleikolm
Life of this patent
Estimating the term…
Abstract
Inorganic sheets (10) of at least two surperposed layers are provided with one or more symbols (20) which have a size of between 1 and 10 μm. The inorganic sheet is made up into pigment flakes (15). The symbols on the pigment flakes (15) allow a tracing of compositions such as printing inks or paintings and of substrates carrying such compositions.
Claims25
An inorganic grindable sheet for making pigments of a predeterminable size, said sheet having a viewing angle dependent shift of color and two outer surfaces substantially parallel to each other and comprising at least a first and a second and a third layer,
- said first and said second layer being selected from materials having different physical properties, wherein said first layer is of a low refractive index material, said second layer is a semi-transparent partially reflecting layer, and said third layer is selected from the group consisting of a semi-transparent partially reflecting layer and an opaque totally reflecting layer,
- said second layer being superposed over said first layer whereby an inner surface is formed between the first and the second layer,
- said third layer being superposed over said first layer opposite to the second layer whereby an inner surface is formed between the first and the third layer,
- said sheet further comprising one or more symbols being formed by at least partial ablation created by a UV excimer laser.
A method of making inorganic pigments carrying at least one symbol comprising the steps of
- a) providing a multi-layered sheet having a viewing angle dependent shift of color and two outer surfaces substantially parallel to each other, said sheet comprising at least a first and a second and a third layer formed by superposition of the layers whereby an inner surface is formed between the first and the second layer and an inner surface is formed between the first and the third layer, wherein the first and the second layers have physical properties different from each other, wherein said first layer is of a low refractive index material, said second layer is a semi-transparent partially reflecting layer, and said third layer is selected from the group consisting of a semi-transparent partially reflecting layer and an opaque totally reflecting layer;
- b) applying at least one symbol on at least one of said surfaces of the layers during and/or after terminating step a) by at least partial ablation with a UV excimer laser;
- c) grinding said sheet of step b) to produce pigment particles.
An inorganic grindable sheet for making pigments of a predeterminable size, said sheet having a viewing angle dependent shift of color and two outer surfaces substantially parallel to each other and comprising at least a first and a second and a third layer, said first and said second layer being selected from materials having different chemical compositions, said second layer being superposed over said first layer whereby an inner surface is formed between the first and the second layer, said third layer being superposed over said first layer opposite to the second layer whereby an inner surface is formed between the first and the third layer, said sheet further comprising one or more symbols being formed by at least partial ablation created by a UV excimer laser.
Dependencies are inferred from the claim text.