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US3989520A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrophotographic dual layer recording material

Assignee: Hoechst AG
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Filing: 1975-05-20
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Granted: 1976-11-02
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Expires: 1995-05-20
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Abstract

Abstract This invention relates to an electrophotographic recording material consisting of an electroconductive support material and a photoconductive double layer of organic materials which consists of a homogeneous, opaque, charge carrier producing dyestuff layer and of a transparent top layer of insulating materials with at least one charge transporting compound.

Inventors

  • 👤 Jurgen Rochlitz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 14:56
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/02; G03G5/04; G03G5/06; G03G5/0622; G03G5/0644; G03G5/0646; G03G5/0653; G03G5/043; G03G5/047; G03G5/0601; G03G5/0609; G03G5/0624; G03G5/0635; G03G5/0637

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 337 words
In an electrophotographic recording material consisting of an electroconductive support material with a photoconductive double layer of organic materials which consists of a tightly packed, homogeneous, uniform, opaque, charge carrier producing dyestuff layer prepared by vacuum-evaporation of the dyestuff and of a transparent top layer of insulating materials with at least one charge transporting compound, the improvement in which the organic dyestuff layer consists of a compound of the general formulae ##SPC2## in which X is --O-- or --S-- or --CO--, and A is --CO--B--CO--, with B being --O-- or --NR--, in which R is hydrogen, C 1 -C 4 alkyl, C 3 C 8 alkoxyalkyl, optionally substituted aryl or an N-heterocyclic radical, and R 1 , r 2 , and R 3 are identical or different and stand for hydrogen, C 1 -C 4 alkyl, C 1 -C 4 alkoxy, amino or nitro groups or halogen and, in the case of Formula I, R 3 also may stand for a benzene ring system, fused between R 3 and A, and in which m is o or 1, and n, p, and q are integers between 1 and 4, and n + p + q ≦ 10, and in which the transparent top layer consists of a mixture of a charge transporting, monomeric, heterocyclic compound selected from the group consisting of oxazoles, oxidazoles, triazoles, imidazoles and pyrazoles with at least one substituted amino group or two alkoxy groups and having an extended π-electron system, and a binder selected from the group of polyester, copolyester, silicone resin, copolymer of styrene wit maleic anhydride and polycarbonate resin, the mixture of the charge transporting compound and the binder being in a ratio by weight of about 1 : 1, the transparent top layer having a thickness of about 5 to about 20 microns and the dyestuff layer having a thickness of about 0.005 to about 2 microns, which recording material is useful in an electrophotographic copying process with negative charging of the top layer if an electron-donating compound is used.
Claim 2
Dependent Claim 337 words
In an electrophotographic recording material consisting of an electroconductive support material with a photoconductive double layer of organic materials which consists of a tightly packed, homogeneous, uniform, opaque, charge carrier producing dyestuff layer prepared by vacuum-evaporation of the dyestuff and of a transparent top layer of insulating materials with at least one charge transporting compound, the improvement in which the organic dyestuff layer consists of a compound of the general formulae ##SPC2## in which X is --O-- or --S-- or --CO--, and A is --CO--B--CO--, with B being --O-- or --NR--, in which R is hydrogen, C 1 -C 4 alkyl, C 3 C 8 alkoxyalkyl, optionally substituted aryl or an N-heterocyclic radical, and R 1 , r 2 , and R 3 are identical or different and stand for hydrogen, C 1 -C 4 alkyl, C 1 -C 4 alkoxy, amino or nitro groups or halogen and, in the case of Formula I, R 3 also may stand for a benzene ring system, fused between R 3 and A, and in which m is o or 1, and n, p, and q are integers between 1 and 4, and n + p + q ≦ 10, and in which the transparent top layer consists of a mixture of a charge transporting, monomeric, heterocyclic compound selected from the group consisting of oxazoles, oxidazoles, triazoles, imidazoles and pyrazoles with at least one substituted amino group or two alkoxy groups and having an extended π-electron system, and a binder selected from the group of polyester, copolyester, silicone resin, copolymer of styrene wit maleic anhydride and polycarbonate resin, the mixture of the charge transporting compound and the binder being in a ratio by weight of about 1 : 1, the transparent top layer having a thickness of about 5 to about 20 microns and the dyestuff layer having a thickness of about 0.005 to about 2 microns, which recording material is useful in an electrophotographic copying process with negative charging of the top layer if an electron-donating compound is used.
Claim 3
Dependent Claim 29 words
A recording material according to claim 1, in which the aryl radical is substituted by C 1 -C 4 -alkyl, C 1 -C 4 -alkoxy, nitro groups or halogen.
Claim 4
Dependent Claim 18 words
A recording material according to claim 1, in which the organic dyestuff layer consists of benzoxanthene-3,4-dicarboxylic acid anhydride.
Claim 5
Dependent Claim 18 words
A recording material according to claim 1, in which the organic dyestuff layer consists of 10-methoxybenzoxanthene-3,4-dicarboxylic acid anhydride.
Claim 6
Dependent Claim 18 words
A recording material according to claim 1, in which the organic dyestuff layer consists of benzothioxanthene-3,4-dicarboxylic acid anhydride.
Claim 7
Dependent Claim 18 words
A recording material according to claim 1, in which the organic dyestuff layer consists of 1,6-dinitro-benzothioxanthene-3,4-dicarboxylic acid anhydride.
Claim 8
Dependent Claim 17 words
A recording material according to claim 1, in which the organic dyestuff layer consists of benzothioxanthene-3,4-dicarboxylic acid-N-(3-methoxy-n-propyl)-imide.
Claim 9
Dependent Claim 17 words
A recording material according to claim 1, in which the organic dyestuff layer consists of benzothioxanthene-3,4-dicarboxylic acid-N-mesityl-imide.
Claim 10
Dependent Claim 17 words
A recording material according to claim 1, in which the organic dyestuff layer consists of benzothioxanthene-3,4-dicarboxylic acid-N-(3-nitrophenyl)imide.
Claim 11
Dependent Claim 14 words
A material according to claim 1, in which the heterocyclic compound is an oxadiazole.
Claim 12
Dependent Claim 13 words
A material according to claim 1, in which the heterocyclic compound is 2,5-bis-(4-diethylaminophenyl)-oxadiazole-1,3,4.
Claim 13
Dependent Claim 19 words
A material according to claim 1 in which the binder is a copolymer from styrene and maleic acid anhydride.
Claim 14
Dependent Claim 15 words
A material according to claim 1 in which the transparent top layer additionally contains sensitizers.

References Cited (Backward Citations)

BE562336A Cited
GB883790A Cited
US3287123A Cited
US3598582A Cited
DE2028319A1 Cited
US3877935A Cited
US3837851A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-11-02 1980-05-03 1980-11-02 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-11-02 1984-05-03 1984-11-02 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-11-02 1988-05-03 1988-11-02 $7700.00 Window Closed / Lapsed

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