Dowa Electronics Materials Co., Ltd.

Kyoto Elex Co., Ltd.

E.i. Dupont De Nemours and Company

Solar Paste, LLC

Takashi Hinotsu

Shingo Teragawa

Michael Stephen Wolfe

Howard David Glicksman

Dave Hui

Hiromasa Miyoshi

Satoru Kurita

Keiichi Endoh

Tomonori Shibayama

Masami Sakuraba

Shinya Sasaki

Toshihiko Ueyama

Haixin Yang

Koji Tanoue

Yutaka Nakayama

Masashi Nakayama

Nobuo Ochiai

Wataru Fujimori

Shinichi Konno

Yoshiko Kohno

Taro Torigoe

Yuto Hiyama

Tatuya Kariyasu

This disclosure relates to a method of manufacturing an electrically conductive thick film comprising steps of: (a) applying a fine silver particle dispersion on a substrate, wherein the fine silver particle dispersion comprises, (i) 60 to 95 wt. % of fine silver particles, wherein particle diameter (D50) of the fine silver particles is 50 to 300 nm, (ii) 4.5 to 39 wt. % of a solvent; and (iii) 0.1 to 3 wt. % of a resin, wherein the glass transition temperature (Tg) of the resin is 70 to 300&#xb0; C., wherein the weight percentages are based on the weight of the fine silver particle dispersion; and (b) heating the applied fine silver particle dispersion at 80 to 1000&#xb0; C.

Fine silver particle dispersion

This disclosure relates to a fine silver particle dispersion comprising: (i) 60 to 95 wt. % of fine silver particles, wherein particle diameter (D50) of the fine silver particles is 50 to 300 nm, (ii) 4.5 to 39 wt. % of a solvent; and (iii) 0.1 to 3 wt. % of a resin, wherein the glass transition temperature (Tg) of the resin is 70 to 300&#xb0; C., wherein the weight percentages are based on the weight of the fine silver particle dispersion.

This disclosure relates to a fine silver particle dispersion including: (1) 65 to 95.4% by weight of fine silver particles which have an average primary particle diameter of 10 to 190 nm and which comprise 25% by number or less of silver particles having a primary particle diameter of 100 nm or larger, (2) 4.5 to 34.5% by weight of a solvent, and (3) 0.1 to 1.0% by weight of ethyl cellulose having a weight average molecular weight of 10,000 to 120,000.

There is produced a fine silver particle dispersing solution which contains: fine silver particles (the content of silver in the fine silver particle dispersing solution being 30 to 95% by weight), which have an average primary particle diameter of greater than 100 nm and not greater than 300 nm and which are coated with an amine having a carbon number of 8 to 12, such as octylamine, serving as an organic protective material; a polar solvent (5 to 70% by weight) having a boiling point of 150 to 300&#xb0; C.; and an acrylic dispersing agent (5% by weight or less with respect to the fine silver particles), such as a dispersing agent of at least one of acrylic acid ester and methacrylic acid ester.

Fine silver particle dispersing solution

This disclosure relates to a conductive paste comprising a fine silver particle dispersion and a glass frit, wherein the fine silver particle dispersion comprising: (1) 65 to 95.4% by weight of fine silver particles which have average primary particle diameter of 10 to 190 nm and which comprise 25% by number or less of silver particles having primary particle diameter of 100 nm or larger, (2) 4.5 to 34.5% by weight of a solvent, (3) 0.1 to 1.0% by weight of ethyl cellulose having weight average molecular weight of 10,000 to 120,000. Also provided are: a method of manufacturing an electrically conductive thick film comprising steps of: (a) applying said fine silver particle dispersion on a substrate, and (b) heating the applied fine silver particle dispersion at 80 to 1000&#xb0; C.; and an electrical device comprising a conductive thick film made with the foregoing paste.

A bonding material of a silver paste contains: fine silver particles having an average primary particle diameter of 1 to 200 nm, each of the fine silver particles being coated with an organic compound having a carbon number of not greater than 8, such as sorbic acid; and a solvent mixed with the fine silver particles, wherein a diol, such as an octanediol, is used as the solvent and wherein a triol having a boiling point of 200 to 300&#xb0; C., a viscosity of 2,000 to 10,000 mPa&#xb7;s at 20&#xb0; C. and at least one methyl group, such as 3-methylbutane-1,2,3-triol or 2-methylbutane-1,2,4-triol, is mixed with the solvent as an addition agent.

Bonding material and bonding method using same

There is produced a fine silver particle dispersing solution which contains: fine silver particles (the content of silver in the fine silver particle dispersing solution is 30 to 90% by weight), which have an average primary particle diameter of 1 to 100 nm and which are coated with an amine having a carbon number of 8 to 12, such as octylamine, serving as an organic protective material; a polar solvent (5 to 70% by weight) having a boiling point of 150 to 300&#xb0; C.; and an acrylic dispersing agent (1.5 to 5% by weight with respect to the fine silver particles), such as a dispersing agent of at least one of acrylic acid ester and methacrylic acid ester.

An aliphatic amine having a carbon number of not less than 6, such as octylamine, hexylamine or oleylamine, serving as an organic protective material is added to water serving as a solvent so that the molar ratio of the aliphatic amine with respect to silver of a silver compound is in the range of 0.05 to 6, a reducing agent, such as hydrazine or NaBH, being added thereto so that the molar ratio of the reducing agent with respect to silver of the silver compound is in the range of 1 to 6, and the silver compound, such as a silver salt or a silver oxide, being added thereto so that the concentration of silver ions in the aqueous reaction solution is in the range of 0.01 to 1.0 mol/L, and then, the silver compound is reduced at a temperature of 10 to 50&#xb0; C. to produce fine silver particles having an average primary particle diameter of 10 to 200 nm. Thus, there is provided a method for producing fine silver particles, the method being capable of inexpensively producing fine silver particles in a short time.

Method for producing fine silver particles

There is provided a metal nanoparticle dispersion which can be bonded at a lower temperature (for example, 200&#xb0; C. or less), and enabling to obtain excellent mechanical properties and electric properties of the bonded portion, the metal nanoparticle dispersion, including: metal nanoparticles, with at least a part of a surface of each particle coated with amine A having 8 or more carbon atoms; and a dispersion medium for dispersing the metal nanoparticles, wherein the dispersion medium contains amine B which is primary, secondary, or tertiary amine having 7 or less carbon atoms, and which is linear alkyl amine or alkanol amine.

Metal nanoparticle dispersion, method for producing metal nanoparticle dispersion, and bonding method

In order to provide an electro-conductive paste bringing no increase of the contact resistance for forming an electrode of a solar cell device, the electro-conductive paste is characterized by containing an electro-conductive particle, an organic binder, a solvent, a glass frit, and an organic compound including alkaline earth metal, a metal with a low melting point or a compound affiliated with a metal with a low melting point.

Electro-conductive paste for forming an electrode of a solar cell device, a solar cell device and method for producing the solar cell device

A bonding material using silver nanoparticles considerably changes in coating-material property in response to a slight change in composition, and the stability thereof has been insufficient for large-amount application. A bonding material which uses silver nanoparticles, meets the requirements for mass printing, attains dimensional stability, and gives a smooth printed surface is provided. The bonding material includes silver nanoparticles which have at least an average primary particle diameter of 1 nm to 200 nm and have been coated with an organic substance having 8 or less carbon atoms, a dispersion medium, and a viscosity modifier composed of an organic substance, and has a viscosity (measured at a shear rate of 15.7 [1/s]) of 100 Pa&#xb7;s or lower and a thixotropic ratio (measured at a shear rate of 3.1 [1/s]/measured at a shear rate of 15.7 [1/s]) of 4 or lower.

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Tokyo, Japan

Takashi Hinotsu