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Hotspots and development trends in the deep processing of silver products. Silver is the cheapest among precious metals, and its traditional uses are as currency as well as in the production of crafts and jewelry. In recent years, with the continuous development of the electronics industry, the industrial applications of silver have also made significant progress. The deep processing of silver involves using silver as an industrial raw material to produce fine chemical products derived from it, such as silver nitrate, silver oxide, ultra-fine silver powder, flake silver powder, potassium cyanide silver, various silver pastes, different types of silver salt photosensitive materials, and various silver-based composite metal materials. These products are primarily used in industries such as the photosensitive industry, electronics and information technology, electroplating, the chemical industry, and antimicrobial applications. Due to advances in digital technology, the consumption of silver in photographic materials – its most traditional industrial application – is declining year by year. Meanwhile, with technological progress and rising living standards, especially the rapid development of the electronics and electrical industry, the deep processing of silver products has given rise to four main areas of focus: the electronics and electrical industry, solder alloys (silver-based alloys), nanosilver, and silver-based antibacterial materials. I. Electrical and electronic industry: 1.1. Electrical contact materials: The application that consumes the most silver in the electrical equipment industry is electrical contact materials. Hundreds of types of contact materials for low-voltage electrical equipment have been developed to date, but only dozens of them have been put into industrial use. They can basically be divided into four series: Ag-Cd series electrical contact materials, Ag-WC series electrical contact materials, Ag-Ni series electrical contact materials, and Ag-MeO series electrical contact materials. Ag-Cd series electrical contact materials, with their excellent corrosion resistance, strong resistance to welding, and low and stable contact resistance, have become universal contacts. However, since cadmium (Cd) vapor is toxic, pollutes the environment, and is harmful to human health, the research on new Ag-MeO series electrical contact materials has become one of the current hot topics. The AgSnO2 electrical contact material has been relatively successfully developed at present; however, it also has issues such as high material hardness, difficulty in deformation, and tendency to break, which greatly limit its applications. The main development trends in silver-based electrical contact materials are: (1) developing an electrical contact material that can completely replace Ag-CdO ； (2) Developing silver-saving contact materials to minimize silver loss is of great economic significance ； (3) Develop composite electrical contact materials by adding effective third components to existing electrical contact materials, thereby improving the performance of those materials. 1. 2-Electron pastes: Silver paste is a fundamental material used in the manufacturing and development of electronic components, thick-film hybrid circuits, and touch elements, and it is the most widely used product among electron pastes. With China’s entry into the WTO, foreign electronics companies have continued to move into the country, and the demand for silver paste in China remains on the rise. Currently, China imports hundreds of tons of silver paste and silver powder each year. There are currently over a dozen types of silver pastes in use, which are primarily applied in products such as car windows, fluorescent displays, capacitors, resistors, resonators, filters, and solar cells. Overall, the main challenges faced in domestic silver paste production are further improving the quality of silver powder and ensuring the performance stability of silver paste produced on a large scale. It should be noted that the future research focuses in silver paste development will be concentrated in two areas: solar cell pastes and silver-ferrous metal composite pastes. In the field of research on silver-base non-ferrous metal composite pastes, Huazhong University of Science and Technology is currently working together with the (Beijing) Xinda Gold and Silver Development Center on the development of silver-copper composite powders and their pastes; the products produced have reached a level close to that of advanced foreign technologies. II. Lead-free solder alloys (silver-based alloys): Tin-lead solder has been in use for a long time due to its excellent welding and performance characteristics. However, with an increasing awareness of the toxicity of lead and higher demands placed on solder joints as the electronics industry develops, especially with the implementation of the EU’s WEEE/ROHS regulations starting from July 1, 2006, it has become imperative to develop lead-free solders as a replacement for traditional tin-lead solder. Currently, significant progress has been made in the research and development of lead-free solders. Some of these lead-free solders have entered the market in certain applications, replacing traditional tin-lead solders to some extent. In recent years, extensive and in-depth research has been conducted both domestically and internationally on binary lead-free solders. The systems studied include the Sn-Bi system, Sn-Ag system, Sn-Zn system, Sn-In system, Sn-Cu system, and Sn-Sb system, among others. At present, various types of lead-free tin solders have been developed in Japan, the United States, the EU, and other regions. The Sn-Ag-Cu series of solders incorporates Cu into the originally effective Sn-Ag solder, thereby reducing its melting point while maintaining its good performance. It also helps to minimize the dissolution of Cu in the welding materials, which is why it has gradually become a lead-free solder standard internationally. It can be said that lead-free solder is a field that is just in its infancy and requires significant development; it represents a new area of interest within the field of advanced silver processing. III. Nanosilver: As a traditional antibacterial material, silver was widely used in ancient times for antibacterial and anti-corrosion purposes. Silver ions can effectively kill bacteria. When the size of these particles is reduced to the nanoscale, their surface area increases significantly. This increase in surface area leads to greater dissociation of silver, raising the concentration of silver ions in the solution and thereby enhancing their biochemical activity, as well as their antibacterial and bactericidal capabilities. Currently, domestic research institutions have developed various silver-based antibacterial products. It is worth noting that nano-silver not only has broad applications in the field of antibacterial properties, but can also be widely used in catalytic materials, battery materials, low-temperature heat conduction materials, the pharmaceutical industry, and conductive pastes. IV. Silver-based antibacterial materials: In terms of the effectiveness of metal ions in killing and inhibiting bacterial activity, the order from highest to lowest is: mercury (Hg), silver (Ag), copper (Cu), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), cobalt (Co), zinc (Zn), and iron (Fe). Among them, metals such as Hg, Cd, Cr, and Pb are highly toxic; in practice, only Ag, Cu, and Zn are used as metal fungicides. Among them, Ag has the strongest bactericidal ability, which is thousands of times that of zinc; whereas copper is mostly used in construction fields such as water pipes and doorknobs. Antimicrobial agents containing silver ions are the most extensively studied at present. Research by American scientists has shown that silver ions can disrupt the respiratory functions of bacteria and viruses as well as their ability to divide cells. Silver’s excellent antibacterial properties give it the potential to become an antibacterial material. Silver-based antibacterial materials are a type of inorganic antibacterial material. Inorganic silver-loaded antibacterial materials possess characteristics such as persistence, durability, broad-spectrum efficacy, good heat resistance, high safety, and low susceptibility to drug resistance. Silver-loaded antibacterial materials have a wide range of applications, and many practical products can be developed using them. Its applications include: antibacterial film products such as PE, PP, and ABS; refrigerator linings, washing machine linings; antibacterial and antifungal packaging materials; antibacterial ceramics; bathtubs, washbasins, toilets; tiles; coatings; antibacterial enamel products; containers, tableware, food containers; and antibacterial fiber products. Summary of key trends in the deep processing of silver products: In summary, the development of deep-processing technologies for silver products will show the following trends: First, the use of silver in photo-sensitive materials will gradually decrease ； Second, the amount of silver used in coinage seals, handicrafts, and jewelry is set to increase steadily. Third, research into the advanced processing of silver in the electronics and electrical industry, as well as the amount of silver used in that sector, will see rapid development ； Fourth, the advancement of lead-free initiatives in the solder industry will create significant opportunities for the further processing of silver ； Fifthly, nano-silver and silver-based antibacterial materials will represent areas with great potential for development in the future.