Method of manufacturing electronic component

• US 6,473,950 B1
• Filed: 12/21/1998
• Issued: 11/05/2002
• Est. Priority Date: 05/07/1997
• Status: Expired due to Fees

• Current Assignee: Teijin Limited
• Original Assignee: Teijin Limited
• Inventors: Kumakawa, Shiro
• Primary Examiner(s): Vo, Peter
• Assistant Examiner(s): TUGBANG, ANTHONY D
• Application Number:
  US09/147,424
• Time in Patent Office: 1,415 Days
• Field of Search: 29/254.1, 29/254.2, 298/30, 297/39, 428/36.4, 428/35.8, 428/418, 361/321.1, 361/321.2, 361/321.4, 361/309, 361/313
• US Class Current: 29/25.42
• CPC Class Codes: H01G 4/18 of synthetic material, e.g. derivatives of cellulose H01G4/16 takes precedence
• CPC Class Codes: H01G 4/206 inorganic and synthetic material
• CPC Class Codes: Y10T 29/43 Electric condenser making
• CPC Class Codes: Y10T 29/435 Solid dielectric type
• CPC Class Codes: Y10T 428/1372 Randomly noninterengaged or randomly contacting fibers, filaments, particles, or flakes
• CPC Class Codes: Y10T 428/31529 Next to metal

Abstract

A manufacturing method for multi-layered electronic parts which is characterized in that from a roll of a polyethylene microporous sheet which has an electrode layer forming agent formed on its surface, contains 45 to 80 volume percent of inorganic filler, and has a thickness of 25 μm or less, tensile strengths of 3 kg/mm² or more in the longitudinal direction and of 1 kg/mm² or more in the transverse direction, and an elongation of 30% or less in the MD direction, layered electronic parts are formed via (a) a step of unwinding the sheet, (b) a step of cutting the sheet in a predetermined length, (c) a step of stacking the cut sheets, and (d) a step of cutting the layered structure and efficient production is made possible.

Claims

1. A manufacturing method for fabricating multi-layered electronic parts comprising:

(a) preparing a roll of a polyethylene microporous sheet having a longitudinal or winding direction and a transverse direction perpendicular to the winding direction, an electrode layer forming agent formed on the surface thereof, containing approximately 45 to approximately 80 volume percent of inorganic filler, having a thickness of approximately 25 μ

m or less, tensile strengths of approximately 3 kg/mm² or more in the winding direction and of approximately 1 kg/mm² or more in the transverse direction, and an elongation of approximately 30% or less in the winding direction, and a solvent representing approximately 0.0 to approximately 5.5 weight percent of said polyethylene microporous sheet, said layered electronic parts formed by further comprising the following steps;

(b) unwinding said roll of the polyethylene microporous sheet,

(c) cutting said polyethylene microporous sheet to a predetermined length,

(d) stacking said cut polyethylene microporous sheets,

(e) cutting a layered structure, and

(f) preparing said polyethylene microporous sheets into a multilayer nonwoven fabric having fibril form substances 0.03 to 3 μ

m in diameter.

2. A manufacturing method for multi-layered electronic parts according to claim 1, further comprising after the step (d) a step:

(d′

) compressing said layered structure.

3. A manufacturing method for multi-layered electronic parts according to claim 1, further comprising after the step (e) the steps:

(g) debinding said layered structure of polyethylene and

(h) calcinating said layered structure with an inorganic filler.

4. A manufacturing method for multi-layered electronic parts according to claim 1, wherein said solvent has a boiling point approximately 200°

C. or lower.

5. A manufacturing method for multi-layered electronic parts according to claim 4, wherein said roll of polyethlylene microporous sheet has a winding density of approximately 0.2 to approximately 12 g/cm³.

6. A manufacturing method for multi-layered electronic parts according to claim 5, further comprising after the step (d) a step:

(d′

) compressing said layered structure.

7. A manufacturing method for multi-layered electronic parts according to claim 5, further comprising after the step (e) the steps:

(g) debinding said layered structure of polyethylene and

(h) calcinating said layered structure with an inorganic filler.

8. A manufacturing method for multi-layered electronic parts according to claim 5, further comprising a step:

(g) debinding said layered structure under the conditions of approximately 25 to approximately 500°

C. and approximately 10 to approximately 150 hours in a nitrogen atmosphere.

9. A manufacturing method for multi-layered electronic parts according to claim 5, wherein said electronic parts are multilayer capacitors.

10. A manufacturing method for multi-layered electronic parts according to claim 5, wherein said polyethylene microporous sheet is subjected to heat treatment at approximately 60 to approximately 120°

C.

11. A manufacturing method for multi-layered electronic parts according to claim 5, wherein said electrode layer forming agent contains metallic particles, said metallic particles having a diameter of 0.03 to 3 μ

m.

12. A manufacturing method for multi-layered electronic parts according to claim 1, further comprising a step:

(g) debinding said layered structure under the conditions of approximately 25 to approximately 500°

C. and approximately 10 to approximately 150 hours in a nitrogen atmosphere.

13. A manufacturing method for multi-layered electronic parts according to claim 1, wherein said roll of polyethlylene microporous sheet has a winding density of approximately 0.2 to approximately 12 g/cm³.

14. A manufacturing method for multi-layered electronic parts according to claim 11, wherein said electronic parts are multilayer capacitors.

15. A manufacturing method for multi-layered electronic parts according to claim 11, wherein said polyethylene microporous sheet is subjected to heat treatment at approximately 60 to approximately 120°

C.

16. A manufacturing method for multi-layered electronic parts according to claim 11, wherein said electrode layer forming agent contains metallic particles, said metallic particles having a diameter of 0.03 to 3 μ

m.

17. A manufacturing method for multi-layered electronic parts according to claim 1, wherein said solvent represents approximately 0.0 to approximately 1.0 weight percent of said polyethylene microporous sheet.