Metal particle dispersion for electroconductive substrates, method for producing the same, and method for producing an electroconductive substrate

Patent metadata

Field	Value
Publication number	US-9972413-B2
Application number	US-201314435561-A
Country	US
Kind code	B2
Filing date	Oct 10, 2013
Priority date	Oct 15, 2012
Publication date	May 15, 2018
Grant date	May 15, 2018

Abstract

The present invention is to provide a metal particle dispersion for electroconductive substrates, which has high dispersibility and dispersion stability and which is able to form a film that shows high electroconductivity after baking. Disclosed is a metal particle dispersion for electroconductive substrates, comprising metal particles, a dispersant and a solvent, wherein the dispersant is a graft copolymer having at least a constitutional unit represented by the following chemical formula (I) and a constitutional unit represented by the following chemical formula (II):

(Symbols in the formulae are as described in the Description.)

First claim

The invention claimed is:

1. A metal particle dispersion for electroconductive substrates, comprising metal particles, a dispersant and a solvent,
wherein the dispersant is a graft copolymer comprising at least a constitutional unit represented by the following chemical formula (I) and a constitutional unit represented by the following chemical formula (II):

wherein R 1 and R 1′ are each independently a hydrogen atom or a methyl group; “A” is a direct bond or a divalent linking group, and the divalent linking group as “A” is at least one selected from the group consisting of an alkylene group comprising 1 to 10 carbon atoms, an arylene group, a —CONH— group, a —COO— group, an ether group comprising 1 to 10 carbon atoms comprising the formula —R′—OR″— wherein R′ and R″ are each independently an alkylene group and combinations thereof; “L” is a direct bond or a divalent linking group, and the divalent linking group as “L” is at least one selected from the group consisting of an alkylene group, an alkylene group comprising a hydroxyl group, an arylene group, a —CONH— group, a —COO— group, a —NHCOO— group, an ether group (—O— group), a thioether group (—S— group) and combinations thereof; and “Polymer” is a polymer chain comprising at least one constitutional unit represented by the following chemical formula (IV) or (V):

wherein R 4 is a hydrogen atom or a methyl group; R 5 is a hydrocarbon group optionally comprising a substituent group, a cyano group or a monovalent group represented by —[CH(R 6 )—CH(R 7 )—O] x —R 8 , —[(CH 2 ) y —O] z —R 8 , —[CO—(CH 2 ) y —O] z —R 8 , —CO—O—R 9 or —O—CO—R 10 ; R 6 and R 7 are each independently a hydrogen atom or a methyl group;
R 8 is a hydrogen atom, a hydrocarbon group optionally comprising a substituent group, or a monovalent group represented by —CHO, —CH 2 CHO or —CH 2 COOR 11 ; R 9 is a hydrocarbon group optionally comprising a substituent group, a cyano group or a monovalent group represented by —[CH(R 6 )—CH(R 7 )—O] x —R 8 , —[(CH 2 ) y —O] z —R 8 or —[CO—(CH 2 ) y —O] z —R 8 ; R 10 is an alkyl group comprising 1 to 18 carbon atoms, and the alkyl group optionally comprises a substituent group; R 11 is a hydrogen atom or an alkyl group comprising 1 to 5 carbon atoms;
the substituent group in R 5 , R 8 , R 9 and R 10 is at least one selected from the group consisting of a nitro group, a halogen atom, an alkoxy group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group and an isocyanate group, and when R 5 , R 8 and R 9 are each a group comprising an aromatic ring, the aromatic ring optionally comprises a substituent group of an alkyl or alkenyl group;
m is an integer of 1 to 5; n and n′ are each an integer of 5 to 200; x is an integer of 1 to 18; y is an integer of 1 to 5; and z is an integer of 1 to 18.

2. The metal particle dispersion for electroconductive substrates according to claim 1 , wherein the graft copolymer as the dispersant further comprises a constitutional unit represented by the following chemical formula (III):

wherein R 1″ is a hydrogen atom or a methyl group; “A′” is a direct bond or a divalent linking group, and the divalent linking group as “A′” is at least one selected from the group consisting of an alkylene group comprising 1 to 10 carbon atoms, an arylene group, a —CONH— group, a —COO— group, an ether group comprising 1 to 10 carbon atoms comprising the formula —R′″—OR″″— wherein R′″ and R″″ are each independently an alkylene group and combinations thereof; and “Q” is a group represented by the following chemical formula (III-a) or a nitrogen-containing heterocyclic group which is able to form a salt with an acid or a halogenated hydrocarbon, and the nitrogen-containing heterocyclic group optionally comprises a substituent group which is at least one selected from the group consisting of a halogen atom, an alkyl group comprising 1 to 12 carbon atoms, an aralkyl group and an aryl group:

wherein R 2 and R 3 are each independently a hydrogen atom or a hydrocarbon group which optionally contains a heteroatom; the hydrocarbon group optionally comprises a substituent group, and the substituent group in R 2 and R 3 is a halogen atom; and R 2 and R 3 can be the same as or different from each other.

3. The metal particle dispersion for electroconductive substrates according to claim 2 , wherein, in the graft copolymer as the dispersant, a salt is formed between at least a part of a nitrogen site contained in the constitutional unit represented by the chemical formula (III) and at least one selected from the group consisting of an acidic phosphorus compound, a sulfonic acid compound and a halogenated hydrocarbon.

4. The metal particle dispersion for electroconductive substrates according to claim 3 , wherein, in the dispersant, the acidic phosphorus compound is a compound represented by the following chemical formula (VI); the sulfonic acid compound is a compound represented by the following chemical formula (VII); and the halogenated hydrocarbon is one or more selected from the group consisting of a halogenated benzyl, a halogenated allyl and a halogenated methyl:

wherein R a and R a′ are each independently a hydrogen atom, a hydroxyl group, a hydrocarbon group optionally comprising a substituent group, or a monovalent group represented by —[CH(R c )—CH(R d )—O] s —R e , —[(CH 2 ) t —O] u —R e or —O—R a″ ; R a″ is a hydrocarbon group optionally comprising a substituent group, or a monovalent group represented by —[CH(R c )—CH(R d )—O] s —R e , —[(CH 2 ) t —O] u —R e , —C(R f )(R g )—C(R h )(R i )—OH or —CH 2 —C(R j )(R k )—CH 2 —OH;
R b is a hydrocarbon group optionally comprising a substituent group, or a monovalent group represented by —[CH(R c )—CH(R d )—O] s —R e , —[(CH 2 ) t —O] u —R e or —O—R b′ ; R b′ is a hydrocarbon group optionally comprising a substituent group, or a monovalent group represented by —[CH(R c )—CH(R d )—O] s —R e or —[(CH 2 ) t —O] u —R e ;
R c and R d are each independently a hydrogen atom or a methyl group; R e is a hydrogen atom, a hydrocarbon group which optionally comprising a substituent group, or a monovalent group represented by —CHO, —CH 2 CHO, —CO—CH═CH 2 , —CO—C(CH 3 )═CH 2 or —CH 2 COOR e′ ; R e′ is a hydrogen atom or an alkyl group comprising 1 to 5 carbon atoms; R f , R g , R h , R i , R j and R k are each independently a hydrogen atom, a hydrocarbon group optionally comprising a substituent group, or a group in which hydrocarbon groups optionally comprising a substituent group are bound by at least one of an ether bond and an ester bond, and R f and R h can be bound to each other to form a cyclic structure; when the cyclic structure is formed, the cyclic structure optionally comprises a substituent group R l , and R l is a hydrogen atom, a hydrocarbon group optionally comprising a substituent group, or a group in which hydrocarbon groups optionally comprising a substituent group are bound by at least one of an ether bond and an ester bond;
the substituent group in R a , R a′ , R a″ , R b , R b′ , R e , R f , R g , R h , R i , R j , R k and R l is at least one selected from the group consisting of a nitro group and a halogen atom, and when R a , R a′ , R a″ , R b , R b′ , R e , R f , R g , R h , R i , R j

Assignees

• Dainippon Printing Co Ltd

Inventors

• Omori Yoshinobu
• Yoshi Naonobu
• Ogura Michihiro
• Murata Tomoki
• Hojo Mikiko

Classifications

• H01B1/22 Primary

  the conductive material comprising metals or alloys · CPC title

• H05K3/10

  in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern · CPC title

• C09D11/52

  Electrically conductive inks · CPC title

• B05D5/12

  to obtain a coating with specific electrical properties · CPC title

• H05K2203/1126

  Firing, i.e. heating a powder or paste above the melting temperature of at least one of its constituents · CPC title