Provided is a method for securing a security document comprising at least personal data pages and a cover sheet placed outside the personal data pages, the method comprising, during security document manufacturing, a step of stitching the personal data pages and the cover sheet together by means of an upper thread and a lower thread interlaced together and a step of treating at least a part of the stitching with ultrasonic welding so as to structurally modify the thread.

Disclosed are an optical anti-counterfeiting element and an optical anti-counterfeiting product. The optical anti-counterfeiting element includes: a substrate, wherein the substrate includes a first surface and a second surface opposite each other; a micrographic layer formed on the second surface of the substrate, wherein the micrographic layer includes a micro-graphic-text region showing a preset graphic-text information and a background region, at least part of the micro-graphic-text region or the background region is covered with a small reflection surface, and the small reflection surface is covered with a color modulation structure; and a sampling layer formed on the first surface of the substrate, wherein the sampling layer is configured for sampling the micro-graphic-text layer and composing, with sampled graphics, the preset graphic-text information of a preset color showing a moire magnification effect. A colored anti-counterfeiting feature with a color varying effect showing a moire magnification effect can be generated without coloring.

Disclosed are an optical anti-counterfeiting element and an optical anti-counterfeiting product. The optical anti-counterfeiting element includes: a substrate, wherein the substrate includes a first surface and a second surface opposite each other; a micrographic layer formed on the second surface of the substrate, wherein the micrographic layer includes a micro-graphic-text region showing a preset graphic-text information and a background region, at least part of the micro-graphic-text region or the background region is covered with a small reflection surface, and the small reflection surface is covered with a color modulation structure; and a sampling layer formed on the first surface of the substrate, wherein the sampling layer is configured for sampling the micro-graphic-text layer and composing, with sampled graphics, the preset graphic-text information of a preset color showing a moire magnification effect. A colored anti-counterfeiting feature with a color varying effect showing a moire magnification effect can be generated without coloring.

The disclosure relates to an optical security feature that is based on a single axis alignment of mirrors or facets in a structured surface that forms a micro mirror array. In an aspect, a device is described that includes a reflecting structure on a first layer, where the reflecting structure has a top surface with multiple embossed facets arranged in a spatial orientation that produces a flat ring optical effect upon incidence of light. In another aspect, a method for making the device is described that provides a reflecting layer and produces the reflecting structure on the reflecting layer with multiple facets arranged in the spatial orientation to produce the flat ring optical effect. In yet another aspect, an apparatus for making the device is described that includes a pressing device and a stamping device to transfer a pattern of the reflecting structure to a reflecting material.

A photonic crystal film, a method for manufacturing the photonic crystal film, and an anti-forgery article comprising the photonic crystal film are disclosed. The photonic crystal film includes a polyurethane-based polymer matrix and colloidal particles dispersed in the polyurethane-based polymer matrix and arranged in a crystal lattice structure. The colloidal particles includes one or more selected from metal nanoparticles, metal oxide nanoparticles, organic nanoparticles, and carbon structure nanoparticles.

A photonic crystal film, a method for manufacturing the photonic crystal film, and an anti-forgery article comprising the photonic crystal film are disclosed. The photonic crystal film includes a polyurethane-based polymer matrix and colloidal particles dispersed in the polyurethane-based polymer matrix and arranged in a crystal lattice structure. The colloidal particles includes one or more selected from metal nanoparticles, metal oxide nanoparticles, organic nanoparticles, and carbon structure nanoparticles.

A device comprising: an optical emitter for emitting light having an emitted optical spectrum; an optical sensor for receiving light reflected from a tag attached to an object; and a processor configured to: determine a reflected optical colour spectrum of the light reflected from the tag based on an output of the optical sensor; retrieve an optical signature associated with said object from memory; and determine the authenticity of said object based on comparing the optical signature and the reflected optical colour spectrum.

A device comprising: an optical emitter for emitting light having an emitted optical spectrum; an optical sensor for receiving light reflected from a tag attached to an object; and a processor configured to: determine a reflected optical colour spectrum of the light reflected from the tag based on an output of the optical sensor; retrieve an optical signature associated with said object from memory; and determine the authenticity of said object based on comparing the optical signature and the reflected optical colour spectrum.

An anti-forgery color conversion film includes a photonic crystal structure whose color is converted by an external stimulus such as a breath. The photonic crystal structure includes a first refractive index layer including a first polymer exhibiting a first refractive index; and a second refractive index layer which is alternately laminated with the first refractive index layer and includes a second polymer exhibiting a second refractive index. A consumer who purchases an article including the color conversion film may easily distinguish the authenticity of the article.

An anti-forgery color conversion film includes a photonic crystal structure whose color is converted by an external stimulus such as a breath. The photonic crystal structure includes a first refractive index layer including a first polymer exhibiting a first refractive index; and a second refractive index layer which is alternately laminated with the first refractive index layer and includes a second polymer exhibiting a second refractive index. A consumer who purchases an article including the color conversion film may easily distinguish the authenticity of the article.