Photoconductor formulation containing boron nitride
View Patent ↗The present disclosure relates to incorporation of boron nitride in the charge transport layer of a photoconductor. The boron nitride may have an aspect ratio of greater than 1.0, a D50 mean particle size of less than about 10.0 μm and be present at about 5.0% (wt) or less in the charge transport layer. The cartridge may also include toner particles wherein the toner particles have a size range of about 1-25 μm and an average degree of circularity of about 0.90-1.0. The photoconductor containing boron nitride when used in an electrophotographic printer may then provide acceptable dark decay and/or photoinduced decay (PID) curves relative to photoconductors that do not contain boron nitride along with improved resistance to toner filming.
1. A printer cartridge comprising:
a photoconductor comprising a support structure, a charge generation layer disposed at least partially over said support structure and a charge transport layer;
boron nitride dispersed in said charge transport layer, wherein said boron nitride:
(a) has an aspect ratio ranging from 5-30;
(b) a D50 mean particle size of less than about 10.0 μm;
(c) is present at about 5.0% (wt) or less in said charge transport layer;
(d) provides a dark decay (DD BN ) that is equal to about (0.7−1.3)(DD), wherein DD represents the dark decay of said photoconductive element in the absence of boron nitride; and
(e) provides a photoinduced decay residual potential at 0.7 uJ/cm 2 that is within about +/−15% of the residual potential of said photoconductor in the absence of boron nitride; and
toner particles wherein said toner particles have a size range of about 1-25 μm and an average degree of circularity of about 0.90-1.0.
2. The cartridge of claim 1 wherein said boron nitride has a D50 mean particle size of greater than 1.0 μm to about 8.0 μm.
3. The cartridge of claim 1 wherein said boron nitride is present at about 0.1 to about 5.0% (wt.).
4. The cartridge of claim 1 wherein said charge transport layer includes a polycarbonate binder and an aryl amine compound.
5. The cartridge of claim 1 wherein said photoconductor is located in a cartridge for an image forming device.
6. The cartridge of claim 1 wherein said charge transport layer comprises a binder and an aryl amine compound.
7. The cartridge of claim 6 wherein said aryl amine compound comprises N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine.
8. The cartridge of claim 1 wherein said charge transport layer has a thickness of up to about 35 microns.
9. The cartridge of claim 1 wherein said cartridge is located in an image forming device.
10. A printer cartridge comprising:
a photoconductor comprising a support structure, a charge generation layer disposed at least partially over said support structure and a charge transport layer containing a polycarbonate binder and an aryl amine compound wherein said charge transport layer is present at a thickness of about 20-30 microns;
boron nitride dispersed in said charge transport layer, wherein said boron nitride:
(a) has an aspect ratio ranging from 5-30;
(b) a D50 mean particle size of less than about 8.0 μm;
(c) is present at about 5.0% (wt) or less in said charge transport layer;
(d) provides a dark decay (DD BN ) that is equal to about (0.7−1.3)(DD), wherein DD represents the dark decay of said photoconductive element in the absence of boron nitride; and
(e) provides a photoinduced decay residual potential at 0.7 uJ/cm 2 that is within about +/−15% of the residual potential of said photoconductor in the absence of boron nitride; and
toner particles wherein said toner particles have a size range of about 1-25 μm and an average degree of circularity of about 0.90-1.0.
11. The printer cartridge of claim 10 wherein said aryl amine compound comprises N,N′-bis(3-methylphenyl)-N,N′-diphenylbenzidine.
12. The printer cartridge of claim 10 wherein said cartridge is located in an image forming device.
13. A method for forming a photoconductor containing a support structure, a charge generation layer and a charge transport layer comprising:
combining a binder and a charge generation compound and coating a portion of the support structure and forming a charge generation layer having a thickness of less than or equal to about 5.0 microns;
combining a binder and a charge transport compound and boron nitride and coating a portion of the charge generation layer to form a charge transport layer at a thickness of less than or equal to about 35 microns, wherein said boron nitride has
(a) has an aspect ratio of greater than 1.0;
(b) a D50 mean particle size of less than about 10.0.um; and
(c) is present at about 5.0% (wt) or less in said charge transport composition;
wherein said photoconductor containing boron nitride when used in an electrophotographic printer provides:
(i) a dark decay (DD BN ) that is equal to about (0.7−1.3)(DD), wherein DD represents the dark decay of said photoconductor in the absence of boron nitride; and
(ii) a photoinduced decay residual potential at 0.7 uJ/cm 2 that is within about +/−15% of the residual potential of said photoconductor in the absence of boron nitride.
14. The method of claim 13 wherein said charge transport compound comprises an aryl amine compound.
15. The method of claim 13 wherein said charge transport layer has a thickness of about 20-30 microns.
16. The method of claim 13 wherein said boron nitride is present at about 0.1 to about 5.0% (wt.).
17. The method of claim 13 including positioning said photoconductor in an image forming device.