Engraved optically variable image device
A method and image made by the method is disclosed wherein non-spherical magnetically alignable optical pigment flakes in transparent carrier are applied to a substrate and are aligned by applying a magnetic field to the substrate. The pigment flakes align along magnetic field lines and a tool for impressing or scribing the flakes is applied to a sub-region of the substrate to realign or remove flakes from a desired region. For example a scribing tool can be used to scribe a signature or other marks within the magnetically aligned flakes. The flakes are then cured and the image is preserved which has optical and tactile features.
1. A method of forming an image, comprising the steps of:
providing a substrate;
coating at least a first region of the substrate with magnetic flakes, each of said magnetic flakes having first and second opposing substantially parallel sides;
aligning the magnetic flakes within the first region so that their opposing sides are substantially orthogonal to the substrate by exposing the magnetic flakes coated on the first region of the substrate to a magnetic field oriented in a predetermined direction; and,
impressing magnetically oriented flakes within a sub-region of the first region to change alignment of flakes within the sub-region so as to form an image in the first region, wherein flakes within the sub-region have a visual appearance that is different from flakes within the first region outside of the sub-region.
2. A method as defined in claim 1 , wherein the step of coating is performed by printing, painting, or spraying the substrate with a carrier including the magnetic flakes.
3. A method as defined in claim 1 , wherein the flakes are within a carrier to form an ink or paint, and wherein the step of impressing includes the use of an engraving tool.
4. A method of forming an image, comprising the steps of:
providing a substrate;
coating at least a first region of the substrate with magnetic flakes;
magnetically orienting the magnetic flakes within the first region by exposing the non-spherical flakes to a magnetic field oriented in a predetermined direction; and,
a) impressing magnetically oriented flakes with within a sub-region of the first region to change alignment of flakes within the sub-region so as to form an image in the first region, wherein flakes within the sub-region have a visual appearance that is different from flakes within the first region outside of the sub-region; or,
b) scribing magnetically oriented flakes within a sub-region of the first region to change alignment of flakes within the sub-region and or to push away flakes from the first region,
so as to form the image, wherein the sub-region has a visual appearance that is different from the first region outside of the sub-region.