1, aluminum silver paste
Contain the effect of aluminium powder pigment coating to achieve excellent luster, flicker, brightness, covering capacity, tinting strength, with the Angle of different color effect, bright mirror, float, etc, must pass a good dispersion performance, but scattered when should pay attention to the following tips and advice:
Tip: aluminum flake easily bent and broken, in the process of coating production if after high speed stirring or other continuous severe processing, its geometric structure is easy to be destroyed, that appear coarse grain, color dark, hiding power and metal moving etc. Bad phenomenon, so there is no high shear dispersion methods should be adopted.
Suggestion: suggest adopting distributed way: first select the appropriate solvents or a mixture of several kinds of solvent. In aluminum slurry and solvent ratio l: 1 or the ratio of 1:2, adding solvent to aluminum slurry, stir gently until smooth (about 10 ~ 20 min), wetting agent and dispersant in the system.
2, the resin system
Many commonly used such as oily coating finishing varnish makings, acrylic, alkyd, epoxy, polyurethane and water based makings, can be applied to float type and the floating type aluminum silver paste pigment. Any paint binders or solvent, in general, as long as the solvents miscibility and aluminum silver paste, and won't cause chemical damage to aluminum silver paste is appropriate. Note: aluminum is amphoteric metal, paint the acid value should be controlled below 7.
The choice of the solvent
The choice of flux is mainly determined by formula of paint. The float type aluminum silver paste can be widely used in polar solvent, such as aliphatic and aromatic hydrocarbon, ester (e.g., butyl acetate), ketone (such as methyl ethyl ketone, methyl isobutyl ketone), alcohols (e.g., ethanol). And float type aluminum silver paste can only use nonpolar solvent, and it is best to higher surface tension of aliphatic or aromatic solvent, especially oil, solvent oil, benzene, toluene and high flash point, naphtha because they can promote the excellent floatability. Water can cause up to aluminum reaction generated hydrogen effect, therefore should strictly control the moisture in the coating under 0.15%, recommended bayer dehydrating agent of coating flux is removed or diluted too much moisture in the material. Containing flux should not be used for any aluminum silver paste pigment.
Drier is chosen
When a system containing aluminum silver paste paint coating need to join metal drier, for non floating aluminum silver paste, only will not react with green scales on the surface of the fatty acids to bottom drier before application. Suggest use cobalt, zirconium, manganese drier.
The selection of aluminum silver paste
Aluminum silver paste, pigment particle size and size distribution of color, to cover up, with the Angle of different color effect and luster has a crucial influence, so the particle size distribution is to choose the important parameters which cannot be ignored when aluminum silver paste, should choose when choosing aluminum silver paste particle size and size distribution stability of the product. Particle size and particle size distribution is not the only technology parameters selection of aluminum silver paste, even if the same particle size and particle size distribution, through different surface treatment or aluminum flake shape, can also lead to tone, hue or metallic, white degree, with the difference of the optical effect such as Angle different color effect, so eventually need what kind of aluminum silver paste paint, also need to make samples to play board with light of comparative analysis, determine the example.