Optical chromotropic anti-counterfeiting pigment

Abstract

The invention discloses an optical chromotropic anti-counterfeiting pigment. A pigment coating comprises a reflection layer; one side surface of the reflection layer is outwardly sequentially and circularly provided with dielectric layers and half-absorption layers; the reflection layer is made of materials selected from one or more than two from Ti, TiN or TiNx; the dielectric layer is made of a material with refractive index smaller than 1.68; and the half-absorption layer is made of materials selected from one or more than two from Ti, TiN or TiNx. According to the environmental protection-type optical chromotropic anti-counterfeiting pigment, the spectral properties are stable; environmental protection properties are also provided when similar grain size properties with the existing chromotropic anti-counterfeiting structure, uniform metal effect luster and angle-dependent optical effects can be ensured; the material combination is non-toxic and harmless to a human body; environmental stability is good; and the optical chromotropic anti-counterfeiting pigment is particularly applicable to safety anti-counterfeiting packaging printing of food, drinks and drugs closely related to human health.

Description

technical field [0001] The invention relates to the technical field of optical anti-counterfeiting, in particular to an optically variable anti-counterfeiting pigment. Background technique [0002] With the continuous development of optical anti-counterfeiting technology, optical variable ink (OVI) prepared by optical variable pigment (OVP) based on the principle of multi-beam interference is becoming more and more common in high-end anti-counterfeiting fields such as currency and securities. Optical variable anti-counterfeiting technology is Based on the angle-dependent heterochromatic effect of optical multi-layer film multi-beam interference, under the condition of changing the incident angle, the reflected beam will shift the reflection spectrum due to the change of the equivalent optical path with the angle, so that the color effect changes with the change of the viewing angle. Produce a discoloration effect, which cannot be reproduced by ordinary scanning / copying. [...

AI Technical Summary

Problems solved by technology

[0003] In recent years, with the progress of optically variable pigment production technology and the continuous improvement of production technology, the application of this type of optically variable anti-counterfeiting pigment has been expanded, and it has been used in some high-end cigarettes and wine packaging, food, medicine, milk powder, beverages and other packaging anti-counterfeiting. It has been applied, and there are more and more manufacturers capable of producing optically variable pigments and inks. However, some heavy metal materials are involved in the use of materials, especially in areas related to national health and safety, such as food and medicine, and the environmental protection performance is poor.

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