subject: Notes And Use Methods Of Bronze Powder [print this page] The bronze powder is a floating flake pigmentThe bronze powder is a floating flake pigment. With a certain proportion of copper, zinc and aluminum alloy in melt milling, it meets to required specifications. Bronze powders colors are: red and gold, green gold, green and red gold, bronze gold and so on. More coarse the bronze powder is, the stronger the sense of metal will be. And it becomes more flashing and brightness. If it is finer, sense of metal reduced, the color is gentler and hiding function is better.
Copper powder under gentle stirring, scores of times to the copper powder in the solvent of 1:1 or 2:1. Under low shear stirring for about 15 minutes to a paste. Adding the required tone gold oil, stir to blend evenly. Solvent adjusted to the desired viscosity. To avoid curling and breaking the flaky copper powder particles in the dispersion process and reduce optical effects, the best choice of blade stirrer or disc scattered, medium-speed stir.
At the same time should avoid the use of nitrocellulose and epoxy resin. Two will be Si chemical reaction to generate the jelly; such as the use of these two resin, it should be as much as possible within a short time. Should be used wherever possible the low acid value of resin, the resin by the acid value as low as possible. Aromatic hydrocarbons and esters help to make the metal powder particles completely wetting to achieve fully dispersed. It should avoid the use of alcohol and ketone solvents and acidification incomplete lipid solvent. Be sure to use high purity resin and solvent (low water content), containing a small amount of water recommended using the molecular sieve to remove the moisture before the copper powder pigments.
Copper powder in the milling process will be added fatty acids, to reduce friction and protect the copper from the oxide, copper powder surface of both fatty acid protective layers. High temperature, water, sweat and alkaline media are very easy to damage the protective layer of copper powder surface, thereby enabling the slow oxidation, gradually lose their metallic luster.
Caused by copper powder gloss because the powder particle size distribution too broad, too large proportion of fine particulates (