Filmy coil and a manufacturing method for such coil
Abstract
Abstract A filmy coil comprising a metal conductive layer of the thin-line type having a spiral pattern on one side or both sides of an optional insulating substrate film or sheet, characterized in that the interval between each adjacent metal conductive line is smaller than the thickness of the metal conductive layer, and a manufacturing method for such a filmy coil characterized in that a photoresist layer, the patterns of both sides thereof being mirror images, is made up on both sides of the metal conductive foil or sheet, then both sides of the photoresist layer are etched to the depth of 30 to 40% of the thickness of the metal conductive foil or sheet by means of chemical etching, one side of the metal conductive foil or sheet is coated by an isolated resin coat or laminated with an isolated substrate film or sheet layer, the other side of said photoresist layer is etched also by means of chemical etching until the etching grooves on both sides pass through to be connected with each other, to produce a filmy coil in the form of a metal conductive layer on a thin-line type, and if desired, two filmy coils can be attached with each other at their undersides.
Inventors
- 👤 Kunitoshi Yamamoto
- 👤 Yasuji Mori
- 👤 Torayoshi Iwata
Bibliographic Details
Claims Analysis
Total Claims: 7References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |