It has been 50 years since the advent of Dacromet technology. Since its advent in the 1950s, Dacromet has been kept secret as a U.S. military patent for 20 years; in the 1970s, after Dacromet was declassified, it began When it was transferred to civilian use, this technology was initially shared by three companies in the United States, France and Japan, and soon Japan became the sole holder of this technology.
my country did not introduce this technology from Japan until the 1990s.
As the source of technology, it stands to reason that Japan’s Dacromet technology should be superior and unmatched in our country, but in fact this is not the case. Our country is only at the upper-middle level, and many of the zinc-chromium coating products developed by our country have reached or even exceeded those of Japan! Why can our country easily surpass Japan? There seems to be only one answer - the United States and France gave up on Dacromet technology without hesitation, while Japan adopted an attitude of inaction in its development and research. A reasonable explanation is that Dacromet has long been determined by the United States, France and Japan to have no research and development value. The reason why Japan has not abandoned it is just because it hopes to obtain more surplus value from it; that is to say , in industrially developed countries, Dacromet is already a product that has lost its vitality and has no further value.
The most important reason why Dacromet has no research and development value is that Dacromet contains chromium ions that are harmful to the environment and human body, especially hexavalent chromium ions, which are carcinogenic. The problem of chromium pollution is attracting more and more attention. In the increasingly stringent environmental regulations in the world, Dacromet is gradually being eliminated from various application fields. This elimination process has already begun in the field of automotive anti-corrosion. European 2000/53/EG stipulates that the content of hexavalent chromium in the anti-corrosion coating on each vehicle produced and sold in Europe shall not exceed 2 grams. BMW, Ford , Volkswagen, General Motors, Volvo and other automobile companies have also formulated and implemented technical standards for chromium-free coatings accordingly. What followed was the electronic and electrical field. The Official Journal of the European Union published the Waste Electrical and Electronic Equipment (WEEE) Directive (2002/96/EC) and the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS) Directive ( 2002/95/EC), the use of hexavalent chromium in metal anti-corrosion coatings for electrical appliances is prohibited.
At present, developed countries have strictly prohibited the production and coating processing of zinc-chromium coating (Dacromet) in their own country; some zero-grade products cannot be treated with zinc-chromium coating (Dacromet). Components are also moved to my country and other countries where pollution control is not strict for processing, and then imported. In the face of this trend, our country is also accelerating the pace of Dacromet restrictions. It is reported that recently, our government has basically determined the content of the "Administrative Measures for the Prevention and Control of Pollution from Electronic Information Products", which clearly stipulates that all electronic information sold within the territory of our country Products must not contain toxic and harmful substances including hexavalent chromium.