Preparing method of microcapsules capable of coating hindered amine stabilizer, hindered phenolic stabilizer and organic dye together

Abstract

The invention discloses a preparing method of microcapsules capable of coating hindered amine stabilizer, hindered phenolic stabilizer and organic dye together. The preparing method includes the following steps that (1) the organic dye, the hindered amine stabilizer and the hindered phenolic stabilizer are dissolved into volatile organic solvent; (2) the solution in the step (1) is poured into silicon dioxide to be adsorbed, then the volatile organic solvent is completely volatilized; (3) silicon dioxide particles in the step (2) are added into a water-phase system and paraffin mixture containing emulsifier, heating is conducted until paraffin is melted, and an emulsion is prepared after high-speed stirring and dispersing, wherein the disperse phase is paraffin liquid droplets wrapping the silicon dioxide particles; (4) the mixed solution of melamine-formaldehyde prepolymer and water is slowly added into the emulsion prepared in the step (3) dropwise under the stirring condition, the pH value is adjusted, the mixture is heated so that the melamine-formaldehyde prepolymer can be polymerized and separated on the surfaces of the paraffin liquid droplets to obtain a microcapsule wall material; the microcapsules are obtained after cleaning and drying.

Description

technical field [0001] The invention belongs to the technical field of organic dye applications, and in particular relates to a preparation method of microcapsules that jointly coat hindered amine stabilizers, hindered phenol stabilizers and organic dyes. Background technique [0002] Organic dyes are one of the most important colorants due to their wide variety, bright colors, high tinting strength and excellent application performance. However, the light resistance, heat resistance, solvent resistance and migration resistance of some varieties are often inferior to inorganic pigments. Microencapsulation technology is a tiny sealed capsule. Microencapsulation technology refers to the technology of using natural or synthetic polymer materials to coat active substances in solid, liquid or gas to form tiny particles, and the particle size is generally in the range of 0.1-1000 μm. Encapsulation of organic dye molecules can isolate it from chemical environments such as acids, ...

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Problems solved by technology

[0004] However, hindered amine light stabilizers are weakly alkaline, and hindered phenolic antioxidants are weakly acidic. In most mature microcapsule coating technologies, it is necessary to adjust the pH of the system from alkaline to acidic to ensure that the capsule wall The material is deposited on the surface of the core material from the solution system, and then forms microspheres. In the initial alkaline system, the hindered phenolic antioxidant is easily damaged by the hydroxyl radical attack in the system. After the system is adjusted to acidity, the hindered amine Light stabilizers are vulnerable to attack by hydrogen ions. Therefore, conventional microcapsule coating methods are difficult to coat hindered amine light stabilizers and hindered phenolic antioxidants with core materials without destroying such stabilizers.

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