Silver paste contains a certain amount of slow-release mineral oil, additives, etc., to ensure its good storage stability and dispersion, so the storage of silver paste requires good sealing, such as aluminum silver paste and asahi silver paste must be closed. If a package cannot be used at once after opening, it must be sealed immediately. Otherwise, a long time of contact with air will cause air-drying oxidation and lead to poor dispersion. The paint film will be granulated and blackened and thickened. Under normal circumstances, intact sealed packaging can be stored for more than one year.
The application of silver paste is the most critical part of the dispersion process. Generally, the silver paste is pre-dispersed in the solvent. If an appropriate wetting agent is added, it can be soaked for a period of time, and then slowly stirred into a uniform thin slurry, and finally added to the pre-prepared paint, you can get the most Good craft effect.
When pre-dispersing silver paste, commonly used solvents are generally: esters, ether alcohols, alcohols, aromatics, etc., among which the esters have the best effect. In addition, it is required that the solvent does not contain water, otherwise the pigment easily reacts with water, causing system instability. From this perspective, the aromatic solvent generally has a lower water content and seems to be better. The ratio of aluminum paste to pre-dispersed solvent is generally: 1:1 to 1:2.
In the process of dispersing the silver paste, it should avoid stirring with high shear force, which is easy to cause deformation of the thin aluminum sheet, which affects the appearance effect, so it should be dispersed by low speed and slow stirring. The optimal dispersion speed and time should be determined through experiments.
Silver paste also has certain requirements for paint. If the acid value of the paint is too high, it will affect the storage stability of the paint, causing the pigment to blacken and return to coarseness.