METHOD FOR PRODUCING CONDUCTIVE SEGMENT, AND CONDUCTIVE SEGMENT

• US 20130025366A1
• Filed: 07/23/2012
• Published: 01/31/2013
• Est. Priority Date: 07/25/2011
• Status: Active Grant

• Current Assignee: Yazaki Corporation
• Original Assignee: Yazaki Corporation
• Inventors: OIKE, Toshio, TANAKA, Kenichi, SHIMIZU, Takafumi, HIROSE, Ryo
• Granted Patent: US 9,157,783 B2
• Time in Patent Office: Days
• US Class Current: 73/313
• CPC Class Codes: B05D 3/02 by baking B05D3/04 takes precedence
• CPC Class Codes: B05D 5/12 to obtain a coating with specific electrical properties
• CPC Class Codes: B05D 7/50 Multilayers
• CPC Class Codes: B32B 15/01 all layers being exclusively metallic making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00
• CPC Class Codes: C22C 5/02 Alloys based on gold
• CPC Class Codes: C22C 5/06 Alloys based on silver
• CPC Class Codes: G01F 23/36 using electrically actuated indicating means G01F23/38 takes precedence
• CPC Class Codes: H01C 1/142 the terminals or tapping points being coated on the resistive element
• CPC Class Codes: H01C 17/281 by thick film techniques
• CPC Class Codes: Y10T 428/12889 Au-base component

Abstract

A method for producing a conductive segment, includes: a step of printing a metal conductive paste on a substrate, and drying the paste; a step of printing other metal conductive paste on the metal conductive paste after drying, and drying the paste; and a step of burning the metal conductive paste after drying and the other metal conductive paste after drying, wherein the conductive metal paste is an Ag—Pd conductive paste comprising silver (Ag) and palladium (Pd), and the other metal conductive paste is an Au conductive paste comprising gold (Au) as a main component; or the metal conductive paste is an Au conductive paste comprising gold (Au) as a main component, and the other metal conductive paste is an Ag—Pd conductive paste comprising silver (Ag) and palladium (Pd).

Claims

1. A method for producing a conductive segment, comprising:

a step of printing a metal conductive paste on a substrate, and drying the paste;

a step of printing other metal conductive paste on the metal conductive paste after drying, and drying the paste; and

a step of burning the metal conductive paste after drying and the other metal conductive paste after drying,

wherein the conductive metal paste is an Ag—

Pd conductive paste comprising silver (Ag) and palladium (Pd), and the other metal conductive paste is an Au conductive paste comprising gold (Au) as a main component;

or

the metal conductive paste is an Au conductive paste comprising gold (Au) as a main component, and the other metal conductive paste is an Ag—

Pd conductive paste comprising silver (Ag) and palladium (Pd).

3. The method for producing a conductive segment according to claim 1, wherein the Au conductive paste further comprises any one of platinum (Pt) and palladium (Pd).

4. The method for producing a conductive segment according to claim 1, wherein the Ag—

Pd conductive paste further comprises any one of gold (Au) or platinum (Pt).

5. The method for producing a conductive segment according to claim 1, wherein at least one of the Ag—

Pd conductive paste and the Au conductive paste further comprises a glass component.

10. The conductive segment according to claim 9, produced by the production method according to claim 1.

2. A method for producing a conductive segment, comprising a step of printing a metal conductive paste on a substrate, drying the paste, and burning the paste;

and

a step of printing other metal conductive paste on the metal conductive paste after burning, drying the paste, and burning the paste,

wherein the conductive metal paste is an Ag—

Pd conductive paste comprising silver (Ag) and palladium (Pd), and the other metal conductive paste is an Au conductive paste comprising gold (Au) as a main component;

or

the metal conductive paste is an Au conductive paste comprising gold (Au) as a main component, and the other metal conductive paste is an Ag—

Pd conductive paste comprising silver (Ag) and palladium (Pd).

6. The method for producing a conductive segment according to claim 2, wherein the Au conductive paste further comprises any one of platinum (Pt) and palladium (Pd).

7. The method for producing a conductive segment according to claim 2, wherein the Ag—

Pd conductive paste further comprises any one of gold (Au) or platinum (Pt).

8. The method for producing a conductive segment according to claim 2, wherein at least one of the Ag—

Pd conductive paste and the Au conductive paste further comprises a glass component.

11. The conductive segment according to claim 9, produced by the production method according to claim 2.

9. A conductive segment comprising a region formed by an Ag—

Pd conductive paste comprising silver (Ag) and palladium (Pd), and a region formed by an Au conductive paste comprising gold (Au) as a main component, those regions being laminated, wherein silver and palladium contained in the Ag—

Pd conductive paste diffuse into the region formed by the Au conductive paste, and gold contained in the Au conductive paste diffuses into the region formed by the Ag—

Pd conductive paste.

12. The conductive segment according to claim 9, wherein the gold (Au) content is 30% by mass or more based on the total mass of the constituent metals, in the laminated region of the Ag—

Pd conductive paste and the Au conductive paste.

13. The conductive segment according to claim 9, wherein in the conductive segment, gold (Au) is contained in an amount of from 15 to 40% by mass and silver (Ag) is contained in an amount of 40% by mass or less.

14. The conductive segment according to claim 9:

wherein

the Ag—

Pd conductive paste is printed on the resistance plate, and then dried or further burned to form a first conductive region, and the Au conductive paste is printed on the first conductive region to form a second conductive region, followed by drying and further burning, or

the Au conductive paste is printed on the resistance plate, and dried or further burned to form a first conductive region, and the Ag—

Pd conductive paste is printed on the first conductive region to form a second conductive region, followed by drying and further burning,

thereby metals of each conductive paste diffuse into the respective other conductive regions, and

a gold (Au) content of from a surface layer to the vicinity of an intermediate layer, of the conductive segment is nearly uniform in a range of 30% by mass.

15. The conductive segment according to claim 14, wherein a film thickness after drying of the region formed by the Au conductive paste is 20% or more in terms of film thickness ratio to the overall film thickness after drying of the first conductive region and the second conductive region.

16. The conductive segment according to claim 14, wherein the gold (Au) in the Au conductive paste is contained in an amount of 95% by mass or more.

17. The conductive segment according to claim 14, wherein the conductive segment is used for a liquid level detector, the liquid level detector comprising:

a resistance plate having arranged thereon a plurality of long conductive segments,

a float moving up and down according to displacement of liquid level to be measured,

a float arm one end of which being fitted to the float, and other end of which being rotatably supported so as to rotate according to up-and-down movement of the float, and

a contact sliding on a plurality of the conductive segment in conjunction with rotation of the float arm according to the liquid level.