Claims
- 1. A device for providing contact charging comprising: an electrophotographic photosensitive member and a charging member, wherein the charging member has an electroconductive substrate and a surface layer thereon for contacting the electrophotographic photosensitive member, wherein the surface layer has a value of volume resistivity higher than that of the electroconductive substrate and comprises:
- (a) a resin selected from the group consisting of polyurethane resins and polycarbonate resins, and
- (b) an alkali metal salt contained therein, and wherein the electroconductive substrate is electrically connected to an external power supply and transfers a charge to an outer surface of said surface layer for contact charging the electrophotographic photosensitive member.
- 2. A device according to claim 1, wherein the surface layer comprises 100 parts by weight of the resin and 0.5-40 parts by weight of the alkali metal salt.
- 3. A device according to claim 1, wherein the alkali metal salt comprises at least one compound selected from the group consisting of: salts of lithium, sodium and potassium with ClO.sub.4, SCN, BF.sub.4, NO.sub.3, CO.sub.3, CS.sub.3, WO.sub.4, BO.sub.2, IO.sub.4, SO.sub.4, S.sub.2 O.sub.3, PO.sub.3, MoO.sub.4, O.sub.3 SCH.sub.3, O.sub.3 SCF.sub.3, SiF.sub.6 and halogen atoms.
- 4. A device according to claim 3, wherein the alkali metal salt comprises at least one compound selected from the group consisting of: LiClO.sub.4, LiSCN.multidot.2H.sub.2 O, KSCN, LiBF.sub.4, NaNO.sub.3, Na.sub.2 CO.sub.3 .multidot.7H.sub.2 O, K.sub.2 WO.sub.4, K.sub.2 CS.sub.3, NaBO.sub.2, LiIO.sub.4, LiSO.sub.4, NaS.sub.2 O.sub.3 .multidot.5H.sub.2 O, KPO.sub.3, Na.sub.2 MoO.sub.4, LiO.sub.3 SCH.sub.3, LiO.sub.3 SCF.sub.3, K.sub.2 SiF.sub.6, LiCl, LiBr, NaBr, LiI, NaI.multidot.2H.sub.2 O, and KI.
- 5. A device according to claim 1, wherein the surface layer has a thickness of 5-500 microns.
- 6. A device according to claim 1, wherein a base layer is disposed between the substrate and the surface layer.
- 7. A device according to claim 6, wherein the surface layer has a volume resistivity of 10.sup.6 to 10.sup.12 ohm.cm, and the volume resistivity of the surface layer is larger than that of the base layer contacting the surface layer.
- 8. A device according to claim 6, wherein the base layer has a volume resistivity which is higher than that of the substrate and lower than that of the surface layer.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1-051623 |
Mar 1989 |
JPX |
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Parent Case Info
This application is a continuation of application Ser. No. 08/161,443, filed Dec. 6, 1993, now abandoned, which, in turn, is a continuation of application Ser. No. 07/487,377 filed Mar. 2, 1990, now abandoned.
US Referenced Citations (14)
Foreign Referenced Citations (7)
Number |
Date |
Country |
272072 |
Jun 1988 |
EPX |
51-013661 |
May 1976 |
JPX |
56-104351 |
Aug 1981 |
JPX |
57-178267 |
Nov 1982 |
JPX |
58-040566 |
Mar 1983 |
JPX |
58-139156 |
Aug 1983 |
JPX |
58-150975 |
Sep 1983 |
JPX |
Non-Patent Literature Citations (1)
Entry |
Patent Abstracts of Japan, vol. 12, No. 456 (P-793) [3033], Nov. 30, 1988-JPA 63-178249. |
Continuations (2)
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Number |
Date |
Country |
Parent |
161443 |
Dec 1993 |
|
Parent |
487377 |
Mar 1990 |
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