Liquid crystal machine-readable anti-false element

Abstract

The invention relates to a liquid crystal machine-readable anti-false element which is provided with at least two regions made of cholesteric liquid crystal materials, wherein the central wavelengths of reflected lights at the same detection angle in the two regions compose first coded information, and the first coded information changes with the detection angle. The first coded information can be detected by an instrument and can avoid unauthorized reproduction, thereby eliminating the possibility of being faked. The liquid crystal machine-readable anti-false element realizes the combinationof second-grade anti-false features and third-grade machine-readable anti-false features, and can avoid the problem that the anti-false effect of the anti-false element can not be ensured by a singleanti-false measure as far as possible. At the same time, based on the anti-false features, the liquid crystal machine-readable anti-false element can also be combined with first-grade light-variable anti-false features based on angle-dependent color variation and other machine-readable and identifiable second-grade anti-false features of infrared, magnetism, ultraviolet and the like. The invention also provides economic goods provided with the liquid crystal machine-readable anti-false element.

Description

technical field [0001] The invention relates to a liquid crystal machine-readable anti-counterfeit element for protecting valuable items, in particular to a liquid crystal machine-readable anti-counterfeit element whose encoded information is composed of central wavelengths of reflected light in different regions. Background technique [0002] With the development of modern reproduction technology, counterfeiting crimes against various brand-name commodities, financial instruments and securities are becoming more and more rampant. By the way, some counterfeit securities have even reached the point where it is difficult to distinguish the real from the fake for the public, causing unnecessary confusion. The sophistication and extensiveness of counterfeiting technology have put forward higher requirements for anti-counterfeiting technology. [0003] At present, a variety of anti-counterfeiting methods have been developed and adopted in the field of anti-counterfeiting technol...

AI Technical Summary

Problems solved by technology

However, 1000 to 2500nm includes a large range, and there are currently pigments on the market that have strong absorption of electromagnetic waves from 1000 to 2500nm and have no obvious absorption of electromagnetic waves at 800nm. Marked anti-counterfeiting level

[0008] To sum up, anti-counterfeiting using the angle-changing optical effect of optical elements or the polarization properties of liquid crystal materials has been widely used, and has played a very good role in anti-counterfeiting for a long time in the past. However, optically variable pigments (OVP) and liquid crystal pigments with polarizing or angle-changing properties for making such optical anti-counterfeiting elements can be easily obtained on the market, and many optical anti-counterfeiting elements have the same or similar angle-dependent The color-changing effect is easy to confuse the public, and pigments with infrared absorption alone are easily available in the market, so a single anti-counterfeiting measure is not enough to ensure that the anti-counterfeiting effect is foolproof

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