Negative Lettering Optical Security Feature

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Solution Overview

Problem

Current security features on value documents, such as ID cards and passports, are not visually appealing and can be difficult to detect with the naked eye, especially when implemented on light backgrounds, and there is a need for features that are easy to produce and adapt to counterfeiting efforts.

Innovation Solution

A document of value with a substrate layer that features a laser-introduced information field, creating a negative writing effect visible with the naked eye, combined with optically variable inks and liquid-crystal effect pigments, which provide angle-dependent tilting effects and enhanced legibility, using a layered structure with electronic components and a lens arrangement for precise laser application.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If conventional positive lettering security features are used, then the security feature is recognizable, but the visual appeal is poor and it is considered unattractive

Engineering Contradiction:
Improvevisual appealVSAvoidlettering style
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The patent applies negative lettering instead of conventional positive lettering. The security feature displays light-colored text on a dark background rather than dark text on a light background, creating a visually appealing inverted appearance that stands out and is considered attractive while maintaining security functionality

Inventive Principle:
Principle #13The other way round (Inversion)

2Reliability

If optically variable inks or STEP colors are used, then security features are provided, but they are dim and not visible against light backgrounds

Engineering Contradiction:
Improvesecurity feature detectionVSAvoidvisibility
Core Design Contradiction:
ReliabilityVSIllumination intensity

Solution Approach 1:

The patent employs optically variable inks that change color based on viewing angle, and uses negative lettering with dark backgrounds to enhance the visibility of these color changes. The dark background provides contrast that makes the optically variable elements clearly visible, and the angle-dependent color shifts create a striking visual effect that is easily detectable

Inventive Principle:
Principle #32Color changes

Solution Approach 2:

The patent utilizes parameters of optically variable materials that change their optical properties (color, reflectivity) based on viewing angle. This creates dynamic visual effects where the security feature appears different from various angles, enhancing both visibility and security while being easily detectable with the naked eye

Inventive Principle:
Principle #35Parameter changes

3Reliability

If new security features are created to increase counterfeiting difficulty, then security is improved, but production effort increases

Engineering Contradiction:
Improvecounterfeiting resistanceVSAvoidproduction effort
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines multiple security elements into a single integrated feature: negative lettering, optically variable inks, and angle-dependent visual effects are merged into one security element. This integration maintains high counterfeiting resistance while simplifying the production process, as all these features can be applied using existing manufacturing technologies in a coordinated manner

Inventive Principle:
Principle #5Merging (Combining)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution provides a visually appealing and secure security feature that is easily detectable with the naked eye, offering a complex and difficult-to-forge optical effect that complements existing security features, enhancing the document's authenticity and resistance to counterfeiting.

Implementation Method 1

a laser is directed at the substrate, and then the surface of the substrate is at least partially carbonized

Methodology Applied
Scientific EffectCarbonization: Pyrolysis

Implementation Method 2

a lens arrangement is provided above the substrate layer such that the laser is directed onto individual lenses and then deflected in such a way that carbonization occurs at a specific point on the substrate

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 3

optically variable inks and liquid-crystal effect pigments, which provide angle-dependent tilting effects

Methodology Applied
Scientific EffectOptical variable effect: Liquid Crystals

Data Source

PatentEP3594012B1Valuable document having optical security feature
Publication Date: 2021.04.07 GIESECKE & DEVRIENT EPAYMENTS GMBH
  • EP3594012B1 patent drawingFigure 1
  • EP3594012B1 patent drawingFigure 2
  • EP3594012B1 patent drawingFigure 3

AI summary

The present invention relates to a security document with an optical security feature that offers a surprising optical effect, which can not only be used as a security feature but also creates a particularly appealing visual effect. The invention also relates to a corresponding method for producing the security document and to a computer program product with control commands that operate the method.