SILVER POWDER AND METHOD FOR PRODUCING THE SAME

• Main Authors: INOUE KENICHI, YOSHIDA MASAHIRO, YAMADA TAKEHIRO, EBARA ATSUSHI, DOMYO YOSHIYUKI
• Format: Patent
• Language: English; Japanese
• Published: 18.05.2017
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CABLES; CASTING; CHEMISTRY; CONDUCTORS; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; INSULATORS; MAKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; METALLURGY; PERFORMING OPERATIONS; POWDER METALLURGY; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING ORDIELECTRIC PROPERTIES; TRANSPORTING; TREATMENT OF ALLOYS OR NON-FERROUS METALS; WORKING METALLIC POWDER

PROBLEM TO BE SOLVED: To provide silver powder in which the average particle diameter is reduced and also a thermal shrinkage percentage is reduced, and a method for producing the same.SOLUTION: While dropping a silver molten metal heated to a temperature (1292 to 1692°C) higher than the melting point (962°C) of silver by 330 to 730°C, it is sprayed with high pressure water (preferably, under the water pressure of 90 to 160 MPa) and is rapidly solidified to powder the silver, thus silver powder in which the average particle diameter is 1 to 6 μm, a shrinkage percentage at 500°C is 8% or lower (preferably, 7% or lower), and the product between the average particle diameter and the shrinkage percentage between at 500°C is 1 to 11 μm % (preferably, 1.5 to 10.5 μm %) is produced.SELECTED DRAWING: Figure 1 【課題】平均粒径が小さく且つ熱収縮率が小さい銀粉およびその製造方法を提供する。【解決手段】銀の融点（９６２℃）より３３０〜７３０℃高い温度（１２９２〜１６９２℃）に加熱した銀溶湯を落下させながら（好ましくは水圧９０〜１６０ＭＰａで）高圧水を吹き付けて急冷凝固させることによって銀を粉末化することにより、平均粒径が１〜６μｍ、５００℃における収縮率が８％以下（好ましくは７％以下）であり、平均粒径と５００℃における収縮率の積が１〜１１μｍ・％（好ましくは１．５〜１０．５μｍ・％）である銀粉を製造する。【選択図】図１