Photoreceptor outer layer and methods of making the same
View Patent ↗The presently disclosed embodiments relate generally to layers that are useful in imaging apparatus members and components, for use in electrophotographic, including digital apparatuses. Embodiments pertain to an improved electrophotographic imaging member used in customer replaceable units (CRU) comprising a very thin outer layer on the imaging member surface, where the outer layer comprises healing materials that act as a barrier against moisture and/or surface contaminants. The improved imaging member exhibits improved xerographic performance, such as reduced wear and deletions in high humidity conditions.
1. A xerographic image forming apparatus comprising:
a) an imaging member having a charge retentive-surface for developing an electrostatic latent image thereon, wherein the imaging member comprises:
a substrate, and
a photoconductive member disposed on the substrate;
b) a holding member holding a source of healing material capable of partially repairing physical or chemical damage to an imaging member surface; and
c) a delivery member separate from the imaging member comprising:
a substrate, and
an elastic outer layer having a thickness of from about 50 nanometer to about 1000 microns disposed on the substrate, wherein the delivery member cyclically delivers the healing material from the holding member onto a surface of the imaging member through a roll-to-roll method and further wherein a surface of the elastic outer layer has a surface pattern comprising an array of periodically ordered indentations or protrusions on the surface of the elastic outer layer formed to control delivery of the healing material.
2. The xerographic image forming apparatus of claim 1 , wherein the elastic outer layer of the delivery member comprises an elastic material selected from the group consisting of polysiloxane, polyurethane, polyester, fluoro-silicone, polyolefin, and mixtures thereof.
3. The xerographic image forming apparatus of claim 1 , wherein the indentations or protrusions of the delivery member have a shape selected from the group consisting of circles, rods, ovals, squares, triangles, polygons, and mixtures thereof.
4. The xerographic image forming apparatus of claim 1 , wherein each of the indentations or protrusions of the delivery member has a perimeter of from about 5 nanometers to about 200 microns.
5. The xerographic image forming apparatus of claim 1 , wherein each of the indentations of the delivery member has a depth of from about 0.5 nanometers to about 100 microns, and wherein each of the protrusions has a height of from about 0.5 nanometers to about 100 microns.
6. The xerographic image forming apparatus of claim 1 , wherein the array of indentations or protrusions of the delivery member have a center-to-center distance of from about 5 nanometers to about 500 microns.
7. A xerographic image forming system comprising:
a) a photoreceptor having a charge retentive-surface for developing an electrostatic latent image thereon, wherein the photoreceptor comprises:
a substrate,
a charge generating layer disposed on the substrate,
at least one charge transport layer disposed on the charge generating layer, and optionally
an overcoat layer disposed on the charge transport layer;
b) a holding member holding a source of healing material capable of partially repairing physical or chemical damage to an imaging member surface;
c) a delivery member separate from the photoreceptor comprising:
a substrate, and
an elastic outer layer having a thickness of from about 50 nanometer to about 1000 microns disposed on the substrate, wherein the delivery member cyclically delivers the healing material from the holding member onto a surface of the imaging member through a roll-to-roll method and further wherein a surface of the elastic outer layer has a pattern comprising an array of periodically ordered indentations or protrusions on the surface of the elastic outer layer formed to control delivery of the healing material and further;
d) a charging and exposure unit for developing an electrostatic image on the photoreceptor surface;
e) a toner developer component for applying a developer material to the charge-retentive surface of the photoreceptor to form a developed image on the charge-retentive surface;
f) a transfer component for transferring the developed image from the charge-retentive surface to a copy substrate; and
g) a cleaning component for cleaning remaining toner particles.
8. The xerographic image forming system of claim 7 , wherein the delivery member is a stamp roll.
9. The xerographic image forming system of claim 7 , wherein the delivery member is placed between charging component and cleaning component.
10. The xerographic image forming system of claim 7 , wherein the holding member is a sponge containing the healing material.
11. The xerographic image forming system of claim 7 , wherein the elastic outer layer of the delivery member comprises an elastic material selected from the group consisting of polysiloxane, polyurethane, polyester, fluoro-silicone, and mixtures thereof.
12. The xerographic image developing system of claim 7 , wherein the indentations or protrusions of the delivery member have a regular shape selected from the group consisting of circles, rods, ovals, squares, triangles, polygons, and mixtures thereof.
13. The xerographic image forming system of claim 7 , wherein each of the indentations or protrusions of the delivery member has a perimeter of from about 5 nanometers to about 200 microns.
14. The xerographic image forming system of claim 7 , wherein each of the indentations of the delivery member has a depth of from about 0.5 nanometers to about 10 microns, and wherein each of the protrusions has a height of from about 0.5 nanometers to about 10 microns.
15. The xerographic image forming system of claim 7 , wherein the indentations or protrusions of the delivery member have a two-dimensional periodicity from hexagonal arrays, tetragonal arrays, quasi-crystal arrays, and linear arrays, and mixtures thereof.
16. The xerographic image forming system of claim 7 , wherein the array of indentations or protrusions of the delivery member have a center-to-center distance of from about 5 nanometers to about 500 microns.
17. An image forming method for xerographic image forming system comprising:
providing the xerographic image forming system of claim 7 ;
applying a healing material onto the surface of the photoreceptor surface through the delivery member;
developing an electrostatic image on the photoreceptor surface containing healing material through charging and exposure unit;
developing a toner image onto the photoreceptor surface through the toner developer component;
transferring the toner image to a printing substrate through the transfer component; and
removing residual toner material from the photoreceptor through the cleaning component.
18. The image forming method of claim 17 , wherein the delivery member comprises an elastic outer layer with a surface pattern comprising an array of periodically ordered indentations or protrusions on the surface of the elastic outer layer and each of the indentations or protrusions of the delivery member has a perimeter of from about 5 nanometers to about 200 microns and a depth of from about 0.5 nanometers to about 10 microns, and wherein each of the protrusions has a height of from about 0.5 nanometers to about 10 microns.