A preparation method and measurement method of a pearlescent pigment cross-section sample for scanning electron microscope determination

Abstract

The invention provides a method for preparing and measuring a pearlescent pigment section sample for scanning electron microscope measurement. The preparation method includes: mixing liquid carbon conductive adhesive and pearlescent pigment and coating it on one side of a silicon chip, drying Obtain an initial sample fixed with a pearlescent pigment coating layer, the pearlescent pigment is coated with at least one continuous film layer and the thickness of the film layer is more than 2 nm; the obtained initial sample is subjected to ion beam cross-sectional polishing to obtain a cross-sectional sample of the pearlescent pigment , The parameters of the ion beam section polishing include: the ion beam accelerating voltage is 3-7 kV; the sample polishing time can be 120-480 minutes; the current is 1.5-3mA.

Description

technical field [0001] The invention relates to a method for preparing the section of a pearlescent pigment observed by a scanning electron microscope using an ion beam section polishing technology, and a method for analyzing and measuring the interface bonding, defects, number of layers, and thickness of a pearlescent pigment film layer using a scanning electron microscope, belonging to The field of pearlescent pigment materials. Background technique [0002] Pearlescent pigment is an inorganic functional material with excellent performance. It has a unique luster similar to pearls, which can endow objects with pearly luster and present a profound three-dimensional texture. The microstructure of pearlescent pigments is a flaky multi-layer core-shell structure, and its coloring principle comes from the synergistic effect of the high-reflection "core" layer material and the high-refraction "shell" layer on the reflection, refraction and interference of incident light. Common...

AI Technical Summary

Problems solved by technology

At present, most of the microscopic analysis of pearlescent pigments is in the grinding and grading of mica, the size and distribution of mica flakes are roughly analyzed, and the surface morphology, cracks, pores and other defects of the pigment are observed with the help of a scanning electron microscope. For the observation of film thickness, its natural cross-section is usually selected, but because the "core" layer of pearlescent pigments is a large-diameter-thick-ratio, flake-shaped material, this results in most of the samples lying flat, and only the coating can be roughly observed. The number of layers cannot accurately measure the film thickness. Even if the film thickness data is obtained, there will be a large deviation due to the influence of the inclination angle; it is even more difficult to measure the film thickness at the nanometer level, so the cross-sectional sample preparation technology of pearlescent pigments is very important. important

At present, the commonly used cross-section sample preparation method is mainly the mechanical polishing method. The mechanical polishing method is used for pearlescent pigments. First, the powder material needs to be fixed with resin, and the powder particles are dispersed in the non-conductive resin. When observing with a microscope, image drift and even charging phenomenon will also occur. On the one hand, it will affect the measurement of the nanoscale microstructure inside the powder, and on the other hand, it will also make the analysis of nanoscale components more difficult.

Secondly, since pearlescent pigments belong to the compound of metal and inorganic, dense and loose structure, due to the differences in rigidity and brittleness of each component unit, mechanical polishing will lead to the destruction of the complex structure, which is likely to cause gaps between the film layers, affecting The authenticity of scanning electron microscope observation; and mechanical polishing will produce a lot of scratches, resulting in far insufficient accuracy for nanoscale film thickness measurement

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