COPPER PARTICULATE DISPERSION, CONDUCTIVE FILM FORMING METHOD, AND CIRCUIT BOARD

• US 20160007455A1
• Filed: 01/31/2014
• Published: 01/07/2016
• Est. Priority Date: 05/15/2013
• Status: Abandoned Application

• Current Assignee: Ishihara Chemical Co., Ltd.
• Original Assignee: Ishihara Chemical Co., Ltd.
• Inventors: KAWATO, Yuichi, ARIMURA, Hidetoshi, KUDO, Tomio
• Application Number:
  US14/769,953
• Publication Number:
  US 20160007455A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B22F 10/10 Formation of a green body
• CPC Class Codes: B22F 7/04 with one or more layers not made from powder, e.g. made from solid metal
• CPC Class Codes: C09D 5/24 Electrically-conducting paints conductive materials H01B1/00
• CPC Class Codes: C09D 7/40 Additives
• CPC Class Codes: C09D 7/61 inorganic
• CPC Class Codes: H01B 1/02 mainly consisting of metals or alloys
• CPC Class Codes: H01B 1/22 the conductive material comprising metals or alloys
• CPC Class Codes: H05K 1/0386 Paper sheets used as reinforcing materials for organic insulating substrates H05K1/0366
• CPC Class Codes: H05K 1/092 Dispersed materials, e.g. conductive pastes or inks
• CPC Class Codes: H05K 1/097 Inks comprising nanoparticles and specially adapted for being sintered at low temperature H05K1/095 takes precedence
• CPC Class Codes: H05K 2201/0302 Properties and characteristics in general
• CPC Class Codes: H05K 2203/0508 Flood exposure
• CPC Class Codes: H05K 2203/10 Using electric, magnetic and electromagnetic fields; Using laser light
• CPC Class Codes: H05K 2203/108 Using a plurality of lasers or laser light with a plurality of wavelengths
• CPC Class Codes: H05K 2203/1131 Sintering, i.e. fusing of metal particles to achieve or improve electrical conductivity
• CPC Class Codes: H05K 2203/1476 Same or similar kind of process performed in phases, e.g. coarse patterning followed by fine patterning
• CPC Class Codes: H05K 3/10 in which conductive material is applied to the insulating support in such a manner as to form the desired conductive pattern
• CPC Class Codes: H05K 3/105 by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam
• CPC Class Codes: H05K 3/1216 by screen printing or stencil printing
• CPC Class Codes: H05K 3/125 by ink-jet printing
• CPC Class Codes: H05K 3/1283 : After-treatment of the printed patterns, e.g. sintering or curing methods
• CPC Class Codes: Y02P 10/25 : Process efficiency

Abstract

Provided is a copper particulate dispersion that can facilitate the formation of a conductive film with low electric resistance by photo-sintering. A copper particulate dispersion includes a dispersion vehicle and copper particulates dispersed in the dispersion vehicle. The copper particulate dispersion contains a sintering promoter. The sintering promoter is a compound that removes copper oxide from copper at a temperature higher than ambient temperature. The sintering promoter thereby removes surface oxide coatings from the copper particulates during the photo-sintering of the copper particulates.

Claims

1. A copper particulate dispersion comprising a dispersion vehicle and copper particulates dispersed in the dispersion vehicle, characterized in that:

the copper particulate dispersion contains a sintering promoter; and

the sintering promoter is a compound that removes copper oxide from copper at a temperature higher than ambient temperature, and it is a compound that forms a complex with copper at a temperature higher than ambient temperature, and it is selected from the group consisting of polyamideimide, polyimide, phosphonic acid, β

-diketone, acetylene glycol, thioether, and sulfate ester; and

the temperature higher than ambient temperature is obtained by irradiation with light for photo-sintering the copper particulates.

9. A conductive film forming method characterized by comprising the steps of:

forming a coating comprising the copper particulate dispersion according to claim 1 on a base material; and

irradiating the coating with light to photo-sinter the copper particulates in the coating, thereby forming a conductive film.

10. A circuit board in which a circuit having the conductive film formed by the conductive film forming method according to claim 9 is provided on a substrate comprising the base material.

2. A copper particulate dispersion comprising a dispersion vehicle and copper particulates dispersed in the dispersion vehicle, characterized in that:

the copper particulate dispersion contains a sintering promoter;

the sintering promoter is a compound that removes copper oxide from copper at a temperature higher than ambient temperature, and it is an alkali that dissolves copper oxide at a temperature higher than ambient temperature, and the alkali is potassium hydroxide; and

the temperature higher than ambient temperature is obtained by irradiation with light for photo-sintering the copper particulates.

11. A conductive film forming method characterized by comprising the steps of:

forming a coating comprising the copper particulate dispersion according to claim 2 on a base material; and

irradiating the coating with light to photo-sinter the copper particulates in the coating, thereby forming a conductive film.

12. A circuit board in which a circuit having the conductive film formed by the conductive film forming method according to claim 11 is provided on a substrate comprising the base material.

3-8. -8. (canceled)