Radiation imagery chemistry: process – composition – or product th – Electric or magnetic imagery – e.g. – xerography,... – Radiation-sensitive composition or product
Reexamination Certificate
2003-03-14
2004-11-16
Goodrow, John L (Department: 1756)
Radiation imagery chemistry: process, composition, or product th
Electric or magnetic imagery, e.g., xerography,...
Radiation-sensitive composition or product
C430S059400, C430S058800
Reexamination Certificate
active
06818366
ABSTRACT:
BACKGROUND
This invention is generally directed to imaging members, and more specifically, the present invention is directed to multilayered photoconductive imaging members containing charge, especially hole transport binders comprised of a polycarbonate crosslinked via pendant silane crosslinking segments.
A number of advantages are associated with the present invention in embodiments thereof, such as excellent electrical characteristics, the provision of robust photoconductive imaging members wherein the life thereof is increased from about 170 kilocycles to over 500 kilocycles, and more specifically, from about 200 to about 510 kilocycles, excellent compatibility with hole transport components, such as aryl amines, resistance to solvents, such as methylenechloride, tetrahydrofuran, and chlorobenzene, and to bias charging rolls. In embodiments of the present invention, the imaging members exhibit excellent cyclic/environmental stability, and substantially no adverse changes in their performance over extended time periods, excellent resistance to mechanical abrasion, and therefore extended photoreceptor life. The aforementioned photoresponsive, or photoconductive imaging members can be negatively charged when the photogenerating layer is situated between the charge transport layer and the substrate.
Processes of imaging, especially xerographic imaging and printing, including digital, are also encompassed by the present invention. More specifically, the layered photoconductive imaging members of the present invention can be selected for a number of different known imaging and printing processes including, for example, color processes, digital imaging processes, digital printers, PC printers, and electrophotographic imaging processes, especially xerographic imaging and printing processes wherein charged latent images are rendered visible with toner compositions of an appropriate charge polarity. The imaging members of the present invention are in embodiments sensitive in the wavelength region of, for example, from about 500 to about 900 nanometers, and more specifically, from about 650 to about 850 nanometers, thus diode lasers can be selected as the light source. Moreover, the imaging members of this invention are useful for color xerographic systems.
REFERENCES
Layered photoresponsive imaging members have been described in numerous U.S. patents, such as U.S. Pat. No. 4,265,990, the disclosure of which is totally incorporated herein by reference, wherein there is illustrated an imaging member comprised of a photogenerating layer, and an aryl amine hole transport layer. Examples of photogenerating layer components include trigonal selenium, metal phthalocyanines, vanadyl phthalocyanines, and metal free phthalocyanines. Additionally, there is described in U.S. Pat. No. 3,121,006, the disclosure of which is totally incorporated herein by reference, a composite xerographic photoconductive member comprised of finely divided particles of a photoconductive inorganic compound dispersed in an electrically insulating organic resin binder. The binder materials disclosed in the '006 patent comprise a material which is incapable of transporting for any significant distance injected charge carriers generated by the photoconductive particles.
The use of perylene pigments as photoconductive substances is also known. There is thus described in Hoechst European Patent Publication 0040402, DE3019326, filed May 21, 1980, the use of N,N′-disubstituted perylene-3,4,9,10-tetracarboxyldiimide pigments as photoconductive substances. Specifically, there is, for example, disclosed in this publication N,N′-bis(3-methoxypropyl)perylene-3,4,9,10-tetracarboxyl-diimide dual layered negatively charged photoreceptors with improved spectral response in the wavelength region of 400 to 700 nanometers. A similar disclosure is presented in Ernst Gunther Schlosser,
Journal of Applied Photographic Engineering
, Vol. 4, No. 3, page 118 (1978). There are also disclosed in U.S. Pat. No. 3,871,882 photoconductive substances comprised of specific perylene-3,4,9,10-tetracarboxylic acid derivative dyestuffs. In accordance with this patent, the photoconductive layer is preferably formed by vapor depositing the dyestuff in a vacuum. Also, there are specifically disclosed in this patent dual layer photoreceptors with perylene-3,4,9,10-tetracarboxylic acid diimide derivatives, which have spectral response in the wavelength region of from 400 to 600 nanometers. Also, in U.S. Pat. No. 4,555,463, the disclosure of which is totally incorporated herein by reference, there is illustrated a layered imaging member with a chloroindium phthalocyanine photogenerating layer. In U.S. Pat. No. 4,587,189, the disclosure of which is totally incorporated herein by reference, there is illustrated a layered imaging member with, for example, a perylene, pigment photogenerating component. Both of the aforementioned patents disclose an aryl amine component, such as N,N′-diphenyl-N,N′-bis(3-methyl phenyl)-1,1′-biphenyl-4,4′-diamine, dispersed in a polycarbonate binder, as a hole transport layer. The above components, such as the photogenerating compounds and the aryl amine charge transport can be selected for the imaging members of the present invention.
SUMMARY
It is a feature of the present invention to provide imaging members with many of the advantages illustrated herein, such as for example extended life, and excellent imaging performance.
A further feature of the present invention is the provision of novel polycarbonates, and improved layered photoresponsive imaging members which are responsive to near infrared radiation exposure, and which imaging members in embodiments possess improved wear resistance.
In a further feature of the present invention there are provided imaging members containing crosslinked binder layers which are compatible with, for example, the transport layer components, and more specifically, wherein the polycarbonate binder, inclusive of the crosslinked components thereof, are miscible with hole transport molecules, such as arylamines, and wherein the photoconductive imaging member possesses excellent electrical performance including high charge acceptance, low dark decay and low residual charge.
Moreover, in another feature of the present invention there is provided abrasion resistant photoconductive imaging members, and wherein the imaging member corrosive erosion by bias charging rolls and mechanical erosion by cleaning blades is avoided or minimized.
Aspects of the present invention relate to a photoconductive imaging member comprised of a supporting substrate, a photogenerating layer, a charge transport layer containing a siloxane-crosslinked polycarbonate binder, and which polycarbonate is crosslinked, for example, by the hydrolysis and condensation of pendent silane groups of the polycarbonate; a photoconductive imaging member comprised of a photogenerating layer, and a charge transport layer, and wherein the charge transport layer comprises hole transport components and a crosslinked polycarbonate component comprised of
wherein R
1
is selected from the group consisting of hydrogen, alkyl, a halogenated alkyl, and aryl; R
2
represents a divalent linkage; Ar
3
and Ar
4
each independently represent aromatic groups; R
3
and R
4
are independently selected from the group consisting of hydrogen, alkyl and aryl; n represents the number of segments; and wherein x and y are the mole fractions of the repeating segments with the value of x+y being equal to 1; a photoconductive imaging member wherein the polycarbonate arylene is selected from the group consisting of
a photoconductive imaging member wherein the polycarbonate possesses a weight average molecular weight M
w
of from about 2,000 to about 500,000, and the crosslinking percentage is from about 10 to about 70; a photoconductive imaging member wherein the crosslinked polycarbonate comprises an adduct formed from the hydrolysis and condensation of a silane-pendent polycarbonate of Formula (III)
wherein R
1
is sel
Allen C. Geoffrey
Goodbrand H. Bruce
Hu Nan-Xing
Qi Yu
Smith Paul F.
Goodrow John L
Palazzo E. O.
Xerox Corporation
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