It is an object of the present invention to provide a conductive fine particle having excellent conductivity, furthermore high adhesiveness with a core particle and little cohesion, a method for producing the conductive fine particle where the plating bath is highly stable and an anisotropic conductive material using the conductive fine particle. The present invention is a conductive fine particle, wherein an alloy plated coating film containing nickel, copper and phosphorous is formed on a surface of a core particle by an electroless plating method; preferably the conductive fine particle, wherein a content of phosphorous in the alloy plated coating film in a direction of a thickness is lower on a surface side of the alloy plated coating film than on a core particle side; a method for producing the conductive fine particle, wherein a first electroless plating reaction is carried out by adding a plating solution containing a nickel salt, a phosphorous reducing agent and a pH adjustor to an aqueous suspension of the core particles supporting a metal catalyst, and then, a second electroless plating reaction is carried out by adding a plating solution containing the nickel salt, a copper salt, the phosphorous based reducing agent and the pH adjustor.

Conductive microparticle, process for producing the same, and anisotropic conductive material

PROBLEM TO BE SOLVED: To prevent any increase of the electric resistance of a solder alloy and degradation of the mechanical strength by suppressing generation of voids in the solder alloy when melting solder powder by preventing oxidation of tin which is oxidized in a relatively easy manner, and to enhance the printability of a solder paste in a fine pitch pattern by setting the mean particle size of the solder powder to be ≤5 μm. SOLUTION: Solder powder has a structure constituted of a center core and a covering layer for covering the center core, and its mean particle size is ≤5 μm. The center core is consists of tin, and the covering layer consists of any one kind of silver, copper, bismuth, or germanium. In addition, the content of tin is 90-99.9 mass%. COPYRIGHT: (C)2008,JPO&INPIT

Solder powder, and soldering paste using the same

An electrically conductive composition comprising a binder and filler particles in which at least a portion of the particles are silver-plated. In one embodiment the composition comprises a binder such as a polyurethane, electrically conductive filler particles, silver-plated filler particles and solvent.

Electrically conductive composition

PROBLEM TO BE SOLVED: To provide silvered copper powder with a silvered layer of high uniformity deposited thereon directly through the silvering treatment without a step of removing hydrophobic substance deposited on copper powder. SOLUTION: Silver is coated on the surface of copper particles through the substitution reaction between silver ions and metal copper in an organic solvent containing solution with silver ions being present therein, or in an emulsion consisting of an organic solvent phase and an aqueous solvent phase with silver ions being present therein. Silver nitrate is favorably used for a silver ion source, and one or more of alcohol, ketone, aldehyde, and ether having solubility to silver salt such as silver nitrate can be used for an organic solvent. Silvered flake-like copper powder having a silvered layer of high uniformity representing the lightness L * of ≥ 50 can be obtained, which is suitable for filler for conductive paste. COPYRIGHT: (C)2006,JPO&NCIPI

Silvered copper powder, its manufacturing method, and conductive paste

The present invention provides a conductive paste comprising flake conductive fillers having a 99% cumulative particle size of 25 μm or less and a binder resin as essential components. The flake conductive fillers are metal particles having a silver-copper alloy surface layer. The conductive paste according to the present invention is fused with a part of a copper foil circuit to which the conductive paste is to be connected during connection by heating and pressurization, and has high electrical conductivity and high fill ration in a via hole. Thus, the conductive paste according to the present invention provides a multilayer printed wiring board that has high reliability of connection and excellent interlayer connection.

Conductive paste and multilayer printed wiring board using the same

PROBLEM TO BE SOLVED: To provide tin-coated copper powder particularly as composite electrically conductive metal power for a substitute for lead-free solder composed of fine particles with the particle diameter of ≤5 μm, having excellent dispersibility and capable of low temperature sintering, and which can form an electrically conductive part. SOLUTION: The tin-coated copper powder is constituted so that the particles of copper powder are used as a core material, and the surface of each particle is provided with a tin-coated layer, wherein the particles of copper powder in which the value of the average particle diameter is 0.1 to 5 μm are used as the core material, and the surface of each particle of the copper powder is provided with a tin-coated layer of 40 to 70 wt.%. COPYRIGHT: (C)2006,JPO&NCIPI

Tin-coated copper powder and composite electrically conductive paste using the tin-coated copper powder

PROBLEM TO BE SOLVED: To provide a silver coated flake of a copper powder whose nugget-like flake of the copper powder is a core material of a granular particle itself, and layer of silver is coated to the surface of the granular particle to lower electric resistance further. SOLUTION: The silver coated flake copper powder is the flake copper powder, a particle diameter of which is not more than 10 μm, and has the silver coated layer on the surface, the value of SD/D 50 of the flake copper powder used as the core material expressed using the standard deviation SD of a particle size distribution measured by a laser diffraction scattering particle size measuring method and a weight cumulative particle diameter D 10 , D 50 and D 90 by the laser diffraction scattering particle size measuring method is not more than 0.5, and also the flake copper powder possesses a powder property that the value expressed by D 90 /D 10 is not more than 4.0, and the silver coated flake copper powder characterized by equipping the surface of granular powder of the flake copper powder with a silver coated layer are used. COPYRIGHT: (C)2004,JPO

Silver coated flake copper powder and method for manufacturing silver coated flake copper powder and conductive paste using silver coated flake copper powder

PROBLEM TO BE SOLVED: To provide a silver-coated copper powder which has excellent electric conductivity and hardly causes deterioration with age in electric conductivity even if allowed to stand in the open atmosphere and also to provide its manufacturing method. SOLUTION: The silver-coated copper powder in which a silver layer is formed on the surface of copper powder, is characterized in that the relationship between the product X (where 0.1≤X≤150 is satisfied) of the weight percent of silver in the silver-coated copper powder and the weight cumulative particle diameter D 50 by laser diffraction/scattering type particle size distribution measurement and the L* by the color difference measurement of the silver-coated copper powder satisfies (63+0.35X-2×10 -3 X2)-L*≤0. COPYRIGHT: (C)2004,JPO

Silver-coated copper powder and its manufacturing method

It is an object to provide a copper-containing tin powder having excellent capabilities in forming fine wiring circuits and filling via holes with ability in bond by melting at a low temperature. In order to achieve the object, it is produced from a copper powder as a starting material by a wet substitution process and it contains remainder of copper un-substituted at 30% by weight or less. The change rate of properties of the copper-containing tin powder, e.g. an average primary particle size or the like is in the range from −20 to +5% with respect to the starting copper powders. The copper-containing tin powder is produced by a wet substitution process in which a copper powder is brought into contact with a plating solution for tin substitution to make copper component constituting the copper powder dissolve with simultaneous substituted deposition of tin.

Copper-containing tin powder and method for producing the copper-containing tin powder, and electroconductive paste using the copper-containing tin powder

Objects of the present invention are to provide oxidation resistant nickel-coated copper powder for conductive paste capable of forming a conductive wiring part for an electronic circuit, and to provide a method for producing the same. In order to achieve the objects, there is provided nickel-coated copper powder which is characterized in that it comprises nickel-coated copper particles in which a core material is copper particles, a catalyst for plating is fixed to a surface of the copper-particles by reduction reaction and electroless plated nickel is applied to the outermost surface. The reduction reaction is characterized in that hydrazine is used as a reducing agent.

Keita Furumoto

Papers

Tin-coated copper powder and composite electrically conductive paste using the tin-coated copper powder

Silver coated flake copper powder and method for manufacturing silver coated flake copper powder and conductive paste using silver coated flake copper powder

Silver-coated copper powder and its manufacturing method

Copper-containing tin powder and method for producing the copper-containing tin powder, and electroconductive paste using the copper-containing tin powder

Nickel-Coated Copper Powder and Method for Producing the Nickel-Coated Copper Powder