Water-soluble silver protecting agent and preparation thereof

Abstract

The present invention provides a water-soluble silver protective agent and a preparation method thereof. The silver protective agent comprises a linear saturated alkane-mercaptan with a carbon chain of 12 to 24, an oligomer wetting agent with a carbon chain less than 12 and hydroxyl functional groups, and an emulsifier. Taking the total weight of the protective agent, the content of the wetting agent is 60-70% by weight; the content of the emulsifier is 20-30% by weight; the content of the linear saturated alkane-mercaptan is 10-15% by weight. The preparation method comprises the following steps: at the temperature of not lower than 60 DEG C, the linear saturated alkane-mercaptan, the wetting agent and the emulsifier are fully emulsified and evenly mixed. The water-soluble silver protective agent provided by the invention has simple technology, low cost, no pollution, and high stability.

Description

technical field [0001] The invention belongs to a silver protecting agent and a preparation method thereof, in particular to a water-soluble silver protecting agent and a preparation method thereof. Background technique [0002] Silver plating has good electrical conductivity, thermal conductivity, solderability, stability, and reliable adhesion to the substrate, and the price of silver is much lower than other precious metals, such as gold and platinum. Therefore, metallic silver is widely used in industries such as electronics, communications, electrical engineering and decoration, especially in the manufacturing process of electronic connectors, semiconductors (LEDs), and integrated circuit lead frames (IC Load-Frames). silver handle. However, during the production, transportation, installation and use of the above-mentioned electronic components, the H in the environment 2 S, SO 2 , CO 2 、CL 2 , NO X When the gas is in contact, even when it is irradiated by ultravi...

AI Technical Summary

Problems solved by technology

However, the chemical passivation method is easy to cause Cr 6+ Pollution; electrolytic passivation method also has Cr 6+ In addition to the problem of pollution, it is also necessary to consider the equipment and process issues related to power supply; coating solvent-based protective agents, and often use harmful and volatile organic solvents such as 1.1.1. Trichloroethane; use Au , Pd, Rh, Pd / Ni alloy coating, but the process is complicated and the cost is high

Moreover, the stability of the existing anti-tarnishing treatment method is not high enough