Claims
- 1. A charging method for applying single polar electrostatic charges onto a first surface of a continuously travelling long web support before coating said support with a coating composition said support having a coating portion and a roulette mark portion on each side of said coating portion, said method comprising the steps of:
- placing a corona discharging electrode adjacent to said first surface of said support, said corona discharging electrode being connected to a direct-current high-voltage electric source and applying single polar electrostatic charge onto said first surface of said support, said corona discharging electrode being wider than said support by a predetermined distance;
- placing a pass roller having a surface that is coated with ceramic adjacent to a second surface of said support such that said pass roller faces said electrode with said support disposed therebetween, said ceramic surface coating having a thickness in the range of greater than or equal to 0.3 mm and less than 0.5 mm;
- causing said support to continuously travel between said corona discharging electrode and said pass roller;
- applying said single polar electrostatic charges on said surface of said continuously travelling long web support by said corona discharging electrode; and
- coating said coating portions of said support with said coating composition.
- 2. A charging method as recited in claim 1, wherein said predetermined distance equals a length of said corona discharging electrode that is at least 10 mm over each end of said coating portion of said support in a width direction thereof.
- 3. A charging method as recited in claim 1, wherein said coating composition is a photographic light-sensitive material.
- 4. A charging method as recited in claim 1, wherein said pass roller is made of at least one of aluminum and stainless steel.
- 5. A charging method as recited in claim 1, wherein said coating is ceramic made of a aluminum oxide particle, and a diameter thereof is not less than 30 .mu.m not more than 40 .mu.m
- 6. A charging method as recited in claim 5, wherein said ceramic surface coating is applied to the surface of said pass roller by a plasma projection.
- 7. A charging method as recited in claim 1, wherein a distance between said corona discharging electrode and said support is not less than 2.5 mm not more than 7.5 mm.
- 8. A charging method as recited in claim 1, wherein said coating composition is a magnetic recording material.
- 9. A charging apparatus comprising:
- a fine wire shaped corona discharging electrode connected to a direct-current high-voltage electric source; and
- a pass roller having a surface coating made of ceramic having a thickness in the range of greater than or equal to 0.3 mm and less than 0.5 mm, said pass roller facing said corona discharging electrode through a long web support that continuously travels therebetween, wherein said corona discharging electrode has a width that is wider than a width of said support by a predetermined distance and applies single polar electrostatic charges onto a surface of said continuously travelling long web support before coating said support with a coating composition.
- 10. A charging apparatus as recited in claim 9, wherein said predetermined distance equals a length of said corona discharging electrode that is at least 10 mm over each end of said coating portion of said support in a width direction thereof.
- 11. A charging apparatus as recited in claim 9, wherein said coating composition is a photographic light-sensitive material.
- 12. A charging apparatus as recited in claim 9, wherein said pass roller is made of at least one of aluminum and stainless steel.
- 13. A charging apparatus as recited in claim 9, wherein said coating is ceramic made of a aluminum oxide particle, and a diameter thereof is not less than 30 .mu.m not more than 40 .mu.m.
- 14. A charging method as recited in claim 13, wherein said ceramic surface coating is applied to the surface of said pass roller by a plasma projection.
- 15. A charging apparatus as recited in claim 9, wherein a distance between said corona discharging electrode and said support is not less than 2.5 mm not more than 7.5 mm.
- 16. A charging apparatus as recited in claim 9, wherein said coating composition is a magnetic recording material.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1-56378 |
Mar 1989 |
JPX |
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Parent Case Info
This is a continuation of application Ser. No. 07/491,999 filed Mar. 12, 1990, now abandoned.
US Referenced Citations (16)
Foreign Referenced Citations (2)
Number |
Date |
Country |
8905477 |
Jun 1989 |
WOX |
2092266 |
Nov 1981 |
GBX |
Non-Patent Literature Citations (1)
Entry |
European Search Report World Patent Index Latest. |
Continuations (1)
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Number |
Date |
Country |
Parent |
491999 |
Mar 1990 |
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