The present invention relates to a method of tagging a substrate with a covert, spectroscopically detectable security feature, wherein a liquid treatment composition comprising at least one acid is deposited onto a substrate, which comprises at least one external surface comprising a salifiable alkaline or alkaline earth compound.

Micro-structures are formed within multilayer laminate security documents by embossing and/or debossing one or more thermoplastic layers prior to lamination of the layers. The embossed and/or debossed structures are arranged and/or formed in a way that creates a number of different security features, including a watermark formed by a relief micro-structure pattern on an opaque film (layer), a multi-color optically variable device, a 3-dimensional feature over kinegram/metallic ink and/or embossment/debossment over printed surfaces.

Micro-structures are formed within multilayer laminate security documents by embossing and/or debossing one or more thermoplastic layers prior to lamination of the layers. The embossed and/or debossed structures are arranged and/or formed in a way that creates a number of different security features, including a watermark formed by a relief micro-structure pattern on an opaque film (layer), a multi-color optically variable device, a 3-dimensional feature over kinegram/metallic ink and/or embossment/debossment over printed surfaces.

A credential with one or more security features is disclosed. The disclosed credential includes a windowed security feature. The windowed security feature is taught to include a mirror element positioned in proximity with a transparent window and a first photo-luminescent feature positioned relative to the transparent window and the mirror element such that the mirror element enhances a luminescence of the first photo-luminescent feature when viewed and illuminated through the transparent window.

A credential with one or more security features is disclosed. The disclosed credential includes a windowed security feature. The windowed security feature is taught to include a mirror element positioned in proximity with a transparent window and a first photo-luminescent feature positioned relative to the transparent window and the mirror element such that the mirror element enhances a luminescence of the first photo-luminescent feature when viewed and illuminated through the transparent window.

A document, product, or package, such as a banknote, passport or the like comprises structures having dichroic effects that change color with viewing angle in both transmission and reflection. Such structures can be useful as security features that counter the ability to effectively use counterfeit documents, products, packages, etc.

A document, product, or package, such as a banknote, passport or the like comprises structures having dichroic effects that change color with viewing angle in both transmission and reflection. Such structures can be useful as security features that counter the ability to effectively use counterfeit documents, products, packages, etc.

The objective of the present invention is to provide an information recording body, a medium and a printed product having improved design properties. An information recording body provided with a superimposed image including a brilliant layer and a transparent layer formed on the brilliant layer is characterized in that: the brilliant layer is a chromatic color image formed from a brilliant material; the transparent layer is a regular pattern image formed from a transparent starting material; the transparent starting material is configured in such a way that an amount of light reflected therefrom differs depending on an observation angle; and the superimposed image is formed in such a way that the transparent layer is recognizable in accordance with a specific observation angle.

A payment card includes hidden features (e.g., textual messages, graphics, emphasis features associated with conspicuous features of the payment card, or the like) undiscernible under only visible light, but discernable under ultraviolet light. The hidden features can be incorporated into multiple layers of a side of the payment card and can be present with different transparencies, different colors, and different persistence.

A payment card includes hidden features (e.g., textual messages, graphics, emphasis features associated with conspicuous features of the payment card, or the like) undiscernible under only visible light, but discernable under ultraviolet light. The hidden features can be incorporated into multiple layers of a side of the payment card and can be present with different transparencies, different colors, and different persistence.