Optical anti-counterfeiting element and preparation method thereof

Abstract

The invention relates to the field of optical anti-counterfeiting and discloses an optical anti-counterfeiting member and a preparation method thereof. The method comprises following steps: forming a fluctuating structure layer having a first zone and a second zone on a same surface of a base material, wherein the specific volume of the fluctuating structure surface in the first zone is less than that of the fluctuating structure surface in the second zone; forming a plating layer on the fluctuating structure layer; forming a protection layer on the plating layer; and the minimum thickness of the protection layer in the first zone is larger than that of the protection layer in the second zone; placing the optical anti-counterfeiting member in an atmosphere which can react with the plating layer until the plating layer in the second zone is completely or partially eroded while the plating layer in the first zone is preserved. The method of the invention has simple technology and high production efficiency and low cost; and accurate hollow-out of plating layer is realized and anti-counterfeiting effect is increased.

Description

technical field [0001] The invention relates to the field of optical anti-counterfeiting, in particular to an optical anti-counterfeiting element and a preparation method thereof. Background technique [0002] In various optical anti-counterfeiting technologies, in order to increase the brightness of images, optical anti-counterfeiting elements generally use metal coatings or high-refractive-index inorganic or organic coatings, or even multi-layer interference film color optically variable coatings. Hollowing out the coating to form a pattern can greatly improve the visual effect and anti-counterfeiting ability of the optical anti-counterfeiting element. [0003] There are generally two traditional techniques for hollowing out the coating, namely water washing and alkali washing. The washing process is to apply washing ink on the position that needs to be hollowed out, then evaporate the coating, and then wet and wash, so that the washing glue layer is dissolved in water, a...

AI Technical Summary

Problems solved by technology

However, the mask layer is often not dense enough, so part of the metal reflective layer in the first area will still be damaged in the final process of removing the metal reflective layer, and it will affect the flow resistance of the product

Evaporating the mask layer requires special evaporation equipment, so the cost is also high

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