Electrophoretic aluminum is the aluminum oxide as the anode, placed in water-soluble emulsion solution, through direct current, artificially deposited on the surface of aluminum oxide film coating film protective layer to form electrophoretic aluminum.
Main features of high-grade electrophoretic aluminum:
1. It has strong paint film hardness.
2, with high adhesion film, not easy to fall off aging.
3. It has stronger weather resistance and alkali resistance than aluminum oxide.
4, the surface color is rich, beautiful, with mirror-like luster effect.
Electrophoretic profiles are more suitable for use outdoors, the national standard 70 years of weather resistance basic second kill other surface treatments.
Electrophoretic profile packaging materials are mostly used for strong adhesion film as a protective film, aluminum profiles in a protective film for a period of time, the film is torn to find that aluminum profiles have film printing or called watermark. There are two kinds of watermarks: one is volatile watermarks, which will disappear after a period of time after the film is torn. The two are non-volatile watermarks, which do not disappear after tearing the film for a year or two. The situation of volatile watermarking almost all aluminum plants have appeared. There are two kinds of watermarks: one is volatile watermarks, which will disappear after a period of time after the film is torn. The two are non-volatile watermarks, which do not disappear after tearing the film for a year or two. The situation of volatile watermarks has appeared in almost all aluminum factories, and there are two kinds of watermarks: one is volatile watermarks, which will disappear after a period of time after the film is torn. The two are non-volatile watermarks, which do not disappear after tearing the film for a year or two. The situation of volatile watermarking almost all aluminum plants have appeared.
Film watermarking is a common phenomenon, film such as air separation, and moisture formation, which has been recognized in the industry. Many factories have also done a large number of relevant experiments. There are several considerations:
1 solidification process experiment
180 degrees 30 minutes basically appear watermark boundary, 200 degrees 10 minutes effect is also better than 180 degrees 30 minutes effect. So the temperature and time is quite key, especially in the case of heat will fade the coloring way, must be integrated to weigh the curing process and color.
2 protective film viscosity and water spray experiment
There were watermarks 24 hours after spraying film for both high viscosity and medium viscosity, while there were almost no watermarks 24 hours after spraying film for low viscosity. It shows that the viscosity of the membrane has a great relationship. But there is a phenomenon, if sprayed with pure solvents such as alcohol, there is no watermark on any viscosity. The author cannot find a reasonable explanation for this phenomenon. I'll leave that to the right person.
3. Problems with electrophoresis tank solution
The above is only from the analysis of the results, but the way of dealing with the problem in another factory makes the author recognize the direction of the fundamental problem.
It is also a watermarking problem, but the delivery is urgent, and the change of low viscosity protective film is not guaranteed to be a problem, but also to observe the time. The workshop director decided to rearrange the electrophoresis tank. (Pull out to empty slot, can be added later). The process was not changed and the problem disappeared. I can't remember any new grooves having similar problems.
The following is only an inference. The equipment owned by the author cannot support verification at present.
In electrophoresis, only the solvent can not be tested. It can be inferred from the above phenomenon that the solvent is reduced, and the principle of recovery equipment is to filter water and solvent from the main tank to water washing, and the solid components of water washing return to the main tank, and achieve the purpose of recovery. The volatile nature of the solvent and the lack of laboratory equipment, resulting in the failure to quantify the proportion of solvent imbalance.
The imbalance of solvent may cause damage to the compactness and uniformity of the paint film, and cause water to enter the paint film, resulting in the formation of watermark.
Sum up the above three points, hope similar cases can be compared to find the problem.
