SECURITY ELEMENTS AND METHODS OF THEIR MANUFACTURE

摘要

A security element including substrate on which is disposed: in first area, a first optically variable device including a diffractive or reflective relief structure and reflection enhancing material following contours of relief structure; and, in second area, a second optically variable device including an iridescent amplitude interference material. First optically variable device is constituted by a plurality of sub-areas arranged in cyclically repeating sequence along predetermined direction of the security element, the plurality of sub-areas collectively forming first area. Relief parameters of diffractive or reflective relief structure vary from one sub-area to next within each repeat cycle whereby, at any viewing angle, each sub-area within any repeat cycle exhibits different diffractive colour or reflected intensity from those of other sub-areas within same repeat cycle, so, when device is tilted, different diffractive colours or reflected intensities appear to move from one sub-area to next within each repeat cycle along predetermined direction.

主权项

1. A security element comprising a substrate on which is disposed:
in a first area, a first optically variable device comprising a diffractive or reflective relief structure and a reflection enhancing material following the contours of the relief structure; and in a second area, a second optically variable device comprising an iridescent amplitude interference material;wherein the first optically variable device is constituted by a plurality of sub-areas arranged in a cyclically repeating sequence along a predetermined direction of the security element, the plurality of sub-areas collectively forming the first area, the relief parameters of the diffractive or reflective relief structure varying from one sub-area to the next within each repeat cycle whereby, at any one viewing angle, each sub-area within any one repeat cycle exhibits a different diffractive colour or reflected intensity from those of the other sub-areas within the same repeat cycle, and such that, when the device is tilted, the different diffractive colours or reflected intensities appear to move from one sub-area to the next within each repeat cycle along the predetermined direction.