Preformed soldering terminal with halogen-free soldering fluxes coated on surfaces

Abstract

The invention provides a preformed soldering terminal with halogen-free soldering fluxes coated on the surfaces, and the performed soldering terminal is good in soldering performance, and the quantity of the soldering fluxes can be controlled easily. A soldering flux coating is formed by the method that the preformed soldering terminal is wetted by halogen-free liquid soldering fluxes and then dried, the halogen-free liquid soldering fluxes are composed of the following components by weight: 35-42% of carrier, 1.0-1.4% of surface wetting agent, 0.5-1.2% of leveling agent, 0.3-0.5% of active agent, 0.1-1.0% of resin film-forming agent, 0.15-1.2% of thickening agent, and the balance is organic solvents. The carrier is rosin, the surface wetting agent is T-80, TX-100 and Span60, the leveling agent is OP-10, the active agent is oxalic acid, salicylic acid and malic acid, the resin film-forming agent is polybutadiene and polyurethane, the thickening agent is hydrogenated castor oil, and the organic solvent is alcohol or ketone which is lower than 110 DEG C in boiling point. The weight of the preformed soldering terminal with the halogen-free soldering fluxes coated on the surfaces is regarded as a standard, the content of the soldering flux coating is 0.2-5.0%, and the preformed soldering terminal with the halogen-free soldering fluxes coated on the surfaces is suitable for soldering of packaging of electronic components.

Description

technical field [0001] The present invention relates to soldering materials, especially solder preforms with flux coatings on their surfaces. Background technique [0002] Currently, the most widely used soldering material in electronic packaging is solder paste. However, when the amount of solder is large and the printing method cannot meet the requirements, it is an ideal and effective way to replace the solder paste with a solder preform coated with flux on the surface. [0003] Solder preform has a specific processing shape and is a commonly used product in current solder. It has the characteristics of precise soldering positioning and accurate quantitative use. It is usually used in occasions that have high requirements for the shape and quality of solder. This kind of solder piece is generally small in size (mm level) and light in weight (mg level), especially for specific plug-in welding and module connection, it has a very good effect on controlling the welding size...

AI Technical Summary

Problems solved by technology

[0005] In order to comply with the trend of advocating and promoting halogen-free flux in the world, and at the same time solve the problem that the flux coating content cannot be controlled during the production of solder tabs, the present invention provides a solder preform whose surface is coated with halogen-free flux. This kind of solder lug has the characteristics of environmental protection, non-sticking, good storage, good welding consistency and high welding precision, and the content of flux coating in the production of solder lugs is easy to control