Stably-colored silicon dioxide particles and preparation method thereof

Abstract

The invention belongs to the technical field of silicon dioxide, and particularly relates to stably-colored silicon dioxide particles and a preparation method thereof. The preparation method comprisesthe following steps: injecting sulfuric acid into a reaction kettle, then adding hydroxyl silicone oil, stirring and activating; adding water glass into the reaction kettle for reaction, adding pigments when the pH of a system is 3-4, stopping addition of the water glass when the pH of the system is 6-7, and continuing stirring until the material system is converted into gel; performing pressurefiltration on the formed silicon dioxide gel, washing, drying and crushing to obtain silicon dioxide particles; adding the silicon dioxide particles into the reaction kettle, adding allyl alcohol polyoxyalkyl ether and chloroplatinic acid-isopropanol, heating for reaction, separating solid particles from a solution after the reaction to obtain colored silicon dioxide particles. The preparation method is simple, and stable in technology; by the preparation method, various types of pigments can be effectively enwrapped, and the prepared colored silicon dioxide particles are very stably colored and are free of phenomena of color change, color fading or color bleeding in practical application.

Description

technical field [0001] The invention belongs to the technical field of silicon dioxide, and in particular relates to a colored silicon dioxide particle with stable coloring and a preparation method thereof. Background technique [0002] Silica is a very important raw material. Through the compounding of silica and pigment, silica particles with porous structure and bright colors can be obtained. And other daily chemical products are more and more widely used, and the demand is also increasing day by day. [0003] At present, the preparation of colored silica particles for toothpaste mainly adopts the sol-gel method. In this method, the reaction raw materials are prepared by reacting under certain conditions to obtain silica sol, and then the sol is emulsified and polymerized with pigments for toothpaste to form di Silica gel, in the process of forming the gel, by controlling the emulsification end point of the reaction process, the required pigment can be uniformly entered ...

AI Technical Summary

Problems solved by technology

[0009] In order to solve the problem of easy discoloration, fading or bleeding of the existing colored silica particles, the invention provides a preparation method of colored and stable colored silica particles, the method uses water glass and sulfuric acid as reaction raw materials, Using food-grade water-soluble pigments or oily pigments as coloring agents, firstly carry out hydrophobic modification with hydroxyl silicone oil, and then make the prepared silica particles hydrophilic with allyl alcohol polyoxyalkyl ether and isopropanol chloroplatinate Modified to produce colored silica particles with very stable coloring