Dowa Electronics Materials Co., Ltd.

Taku Okano

Kimitaka Sato

Yutaka Hisaeda

Noriaki Nogami

Yu Saito

Kozo Ogi

Yoshio Moteki

Taro Nakanoya

Genta Sasaki

Kairi Otani

A silver powder mixture that is suitable for forming a conductive film on a surface of a member having stretchability, a method for producing the same, and a conductive paste using the silver powder mixture is provided. A silver powder mixture containing filamentous silver powder including spherical and filamentous parts and flaky silver powder having an average particle diameter of 1 &#x3bc;m or more and 50 &#x3bc;m or less and an aspect ratio, which is defined by a ratio of an average long diameter and an average thickness, of 1.5 or more is obtained by adding one kind or two or more kinds of a salt of copper and aluminum and ethylenediaminetetraacetic acid to a silver nitrate aqueous solution, for 60 seconds or more, and then adding a reducing agent containing one kind or two or more kinds of L-ascorbic acid, erythorbic acid, and salts thereof.

Silver powder mixture, method for producing same, and conductive paste

There is provided an inexpensive silver particle dispersing solution being usable as a slurry for ink jet, a method for producing the same, and a method for producing a conductive film using the silver particle dispersing solution. In a silver particle dispersing solution containing a silver powder and a solvent, the silver powder has an average primary particle diameter (D) of 0.15 to 0.5 &#x3bc;m, and the ratio (D/D) of a particle diameter (D), which corresponds to 50% of accumulation in volume-based cumulative distribution of the silver powder, to the average primary particle diameter (D) is not less than 1.7, the silver powder having a fatty acid adhered to the surface thereof, and the solvent containing a monohydric higher alcohol having a carbon number of 6 to 12, butyl carbitol or butyl carbitol acetate as the main component thereof.

Silver particle dispersing solution, method for producing same, and method for producing conductive film using silver particle dispersing solution

To provide a silver-coated graphite mixed powder including: silver-coated graphite particles each including a graphite particle and silver coated on a surface of the graphite particle, where when a solution obtained by dissolving the silver-coated graphite mixed powder in nitric acid is analyzed through inductively coupled plasma (ICP) emission spectrometry, an amount of silver is 5% by mass or more but 90% by mass or less, an amount of tin is 0.01% by mass or more but 5% by mass or less, and an amount of zinc is 0.002% by mass or more but 1% by mass or less.

Silver-coated graphite particles, silver-coated graphite mixed powder and production method therefor, and conductive paste

Provided is a silver micropowder coated with a protective material and capable of more drastically reducing the sintering temperature than before. The silver micropowder comprises silver particles processed to adsorb hexylamine (CH&#x2014;NH) on the surfaces thereof and having a mean particle diameter Dof from 3 to 20 nm or an X-ray crystal particle diameter Dof from 1 to 20 nm. The silver micropowder has the property of forming a conductive film having a specific resistivity of not more than 25 &#x3bc;&#x3a9;&#xb7;cm when it is mixed with an organic medium to prepare a silver coating material and when a coating film formed of it is fired in air at 120&#xb0; C. Even when fired at 100&#xb0; C., it may form a conductive film having a specific resistivity of not more than 25 &#x3bc;&#x3a9;&#xb7;cm. The silver micropowder can be produced by mixing a silver particle dispersion, as monodispersed in an organic medium, of silver particles coated with a primary amine A having an unsaturated bond and having a molecular weight of from 200 to 400, and hexylamine, and then keeping the mixture at 5 to 80&#xb0; C. with stirring to thereby form precipitated particles.

Silver micropowder, silver ink, silver coating, and methods for production of these materials

A silver fine powder comprising silver particles with an average particle diameter of 20 nm or less and having an organic protective material on the surface thereof, wherein the proportion of the organic protective material present is 0.05 to 25% by mass based on the total mass of the silver particles and the organic protective material. An amine compound having a molecular weight of 100 to 1,000 is preferably used as the organic protective material, and that having one or more unsaturated bond in one molecule is particularly preferred. This silver fine powder has, for example, a crystallite diameter in (111) crystal plane of silver particle of 20 nm or less. The present invention further provides an ink comprising particles of the silver fine powder dispersed in an organic solvent in the silver concentration of 10% by mass or more, the ink having a viscosity of 50 mPa&#xb7;s or less.

Growing community of inventors

Tokyo, Japan

Taku Okano