High-tap density micro aluminum powder and method for producing the same

Abstract

The invention discloses minute silver powder with high tap density and a method for producing the same. The silver powder has the following properties: the average particle diameter of the silver powder is between 0.3 and 1.5 mu m; the tap density of the silver powder is not less than 4.5g / cm<3>; and the contraction rate of the silver powder is less than or equal to 19 percent after the silver powder is sintered at the temperature of less than or equal to 900 DEG C. The production method comprises: (1) preparing a solution containing silver ions for standby; (2) preparing a reducer aqueous solution containing a dispersant for standby; (3) preparing a treatment solution containing a treating agent for standby; (4) mixing and reacting the solution containing the silver ions and the reducer solution containing the dispersant for reducing the silver ions to silver particles; (5) filtering out a reaction solution, and cleaning the silver particles by deionized water; (6) pumping and leaching the cleaned silver powder, putting the cleaned silver powder into the treatment solution for treatment; and subsequently, filtering out the treatment solution; and (7) drying the silver powder in a vacuum oven; and pulverizing the dried silver powder to obtain the minute silver powder with high tap density. Silver slurry prepared from the silver powder is printed on a magnet body or a substrate, is sintered at temperature of less than or equal to 900 DEG C and has good matching property with the magnet body or the substrate. The minute silver powder is suitable for a manufacturer for producing an electronic element.

Description

technical field [0001] The present invention is related to the processing and property improvement of metal powder, in particular, it relates to high tap density fine silver powder and its production method. technical background [0002] Chip electronic devices, such as resistors, capacitors, inductors, printed circuit boards, mostly use metal paste to form a certain pattern by printing, dip coating, etc., and then form a conductor after sintering. Conventional metal paste contains metal powder, organic solvent, polymer resin, inorganic oxide, dispersant, glass and other components. The traditional production method of silver powder used in the preparation of slurry is mostly chemical reduction method. However, the traditional chemical reduction method is not easy to produce particle size <1.5μm, tap density not less than 4.5g / cm 3 of silver powder. However, with the miniaturization of electronic products, electronic components are required to be smaller and smaller, a...

AI Technical Summary

Problems solved by technology

These inventions all pay attention to the particle size of the silver powder, but they do not pay attention to the tap density of the silver powder; however, if the tap density of the silver powder is small, the shrinkage of the silver line during firing is large, which cannot match the shrinkage of the magnet or the substrate, and the metal The wire breaks, forming an open circuit

So far, there is no patent application for high tap density silver powder