Water-based aluminum silver paste and preparation method thereof

Abstract

The invention provides a water-based aluminum silver paste and a preparation method thereof. The preparation method for the water-based aluminum silver paste comprises the following steps: a) mixing an oily aluminum silver paste, an organic solvent and a silane coupling agent with water, and separating a solid mixture from the solvent; b) mixing the solid mixture and water with the organic solvent and adjusting pH to 7-8, thereby obtaining a mixed liquor; and c) mixing the mixed liquor and the silane coupling agent with ethyl orthosilicate, and aging after reacting, thereby obtaining the water-based aluminum silver paste. According to the preparation method, during the process of preparing the water-based aluminum silver paste, firstly, the silane coupling agent is utilized to preprocess the oily aluminum silver paste, so as to form covalent bond connection on the surface of the oily aluminum silver paste, and then the silane coupling agent and the ethyl orthosilicate are dropwise added, so as to form coverage on the surface of the aluminum silver paste by the silicon dioxide hydrolysed from the ethyl orthosilicate, and lastly, the prepared aluminum silver paste has high brightness, high covering power and better compatibility with resins.

Description

technical field [0001] The invention relates to the technical field of coatings, in particular to a water-based aluminum-silver paste and a preparation method thereof. Background technique [0002] Aluminum silver paste is a kind of aluminum metal pigment. Its production method is to mix spherical aluminum powder, solvent oil, oleic acid and ball milling medium steel balls, and then grade and sieve after ball milling for 6-30 hours. It is a paste metal pigment obtained after kneading. . Aluminum silver paste has become the most widely used and researched metallic pigment due to its unique metallic luster effect, angle-dependent color effect, optical effect and suspension characteristics. [0003] With the development of water-based coatings, the traditional oily aluminum silver paste is not easy to disperse in water-based coatings due to the presence of a large amount of solvent oil, making it unsuitable for water-based coatings; and aluminum is an amphoteric metal. The pa...

AI Technical Summary

Problems solved by technology

The above method is coated with a single substance, and the required amount of tetraethyl orthosilicate is relatively large, and the gloss effect of the aluminum sheet after coating is significantly reduced. Therefore, the obtained water-based aluminum paste has poor whiteness, brightness, and poor hiding power; There are a lot of hydroxyl groups on the silicon surface, which makes the water-based silver-aluminum paste hydrophilic and oleophobic. In water-based paints, the silica-coated water-based aluminum paste has poor compatibility with resins, resulting in poor film stability.

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