Preparation method for surface-coated magnesium fluoride laser aluminum powder

Abstract

The invention discloses a preparation method for a surface-coated magnesium fluoride laser aluminum powder optically-variable pigment, and relates to a preparation method for a surface-coated magnesium fluoride laser aluminum powder. The preparation method comprises the following steps: plating magnesium fluoride, aluminium and magnesium fluoride on the surface of a plastic film sequentially through a vacuum coating method to obtain a three-layer composite coating; performing laser mould pressing on the composite coating at a high temperature to generate a laser colorful effect; pulverizing the laser composite coating through the laser cutting technology to obtain laser sheet powder, mixing and heating the obtained laser sheet powder with an organic solvent to enable the coating layer to be separated from plastic, carrying out hydrocyclone separation to obtain a laser plating slurry, adding a surface treating agent, drying and classifying to obtain the surface-coated magnesium fluoride laser aluminum powder. Paint (printing ink) prepared by the powder has no appearance color change dead angle, and is obvious in color change effect, and bright in color; the average grain size of the powder (d50) is 10-50 microns, the thickness is 70-140 nm, the solid content is equal to or larger than 99%, and the powder is free of organic solvents, stable during storage, and convenient to store and transport.

Description

technical field [0001] The invention relates to the field of functional materials, in particular to a preparation method of a laser aluminum powder optically variable pigment coated with magnesium fluoride on the surface. Background technique [0002] The discoloration of fish scales and jewelry in nature, and the rainbow phenomenon of oil film and soap bubbles are all optical discolorations, which are caused by physical phenomena such as reflection, refraction and interference of light by parallel interfaces of multilayer films. [0003] The world's first advanced optical variable pigment is "Chameleon" (Variocrom) launched by German BASF company in 1999. Its manufacturing process is to use high vacuum evaporation coating or ion sputtering method to combine total reflection layer (core), dielectric layer Substances such as translucent layers are deposited together sequentially to form a multilayer thin film sheet. When the viewing angle changes, incident light undergoes phy...

AI Technical Summary

Problems solved by technology

[0005] However, the laser aluminum paste has the following disadvantages in practical application: First, aluminum is not resistant to acid and alkali and is easy to oxidize. Once even slight acid and alkali corrosion or oxidation occurs, its discoloration effect will be greatly reduced. Laser aluminum paste requires supporting use The resin has a low acid value, and many applications have special requirements for adhesion and surface finish. At this time, the resin used is often of high acid value, and the laser aluminum paste is not corrosion-resistant, and its application is limited; There are dead corners in the discoloration of different angles. In the dead corners, the color is dim and gray. Especially when spraying, the dead corners show dim and gray spots, which greatly affects the surface decoration effect. The third is that aluminum will oxidize and release hydrogen when it meets water. , can not be exposed to water for a long time, so the laser aluminum paste cannot be used in water-based systems; Fourth, about 80% of the laser aluminum paste is organic solvents, which brings great inconvenience to the storage and transportation of the product