JPH0391757A - Drum-like photoconductor and method of manufacturing the same - Google Patents

Abstract

PURPOSE: To prevent the occurrence of spots formed when a drum-shaped photoconductor is continuously used by providing a cylindrical outside surface with an aluminum core formed with a reflection surface of a non-mirror finished surface adjusted in roughness. CONSTITUTION: The cylindrical surface 23 on the outer side of a core member 21 is so worked as to constitute the reflection surface of the non-mirror finished surface to a laser 14 to be scanned. For example, the surface 23 is subjected to a diamond rotational treatment, then to a light polishing treatment. A barrier layer 22 which is discoated on the cylindrical outside surface 23 of the core member 21 is cured to a crosslinked form and, thereafter, the surface thereof is dip-coated with a continuous CGL 24. The CGL 24 is constituted with a solvent contg. a resin, such as toluene sulfone amide resin, hydroxysquelilium charge generating particulates and amine solvent system. Further, the surface thereof is coated with a CTL 25 consisting of a diffusing agent contg. a polycarbonate resin, polyester resin, DEH transfer particulates and a solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to the field of cylindrical photoconductor drums for use in electrophotographic reproduction machines, and more particularly to layered photoconductors for use in xerographic printers having laser scanning imaging stations. Regarding drums.

BACKGROUND OF THE INVENTION As is well known to those skilled in the art, in electrophotographic or xerographic reproduction machines, photoconductors or A static latent image is formed on the photoreceptor drum.

A known type of photoconductor is coated with a barrier/adhesion layer, followed by a charge generating layer (CGL) and a charge transport layer (CGL).
TL) is a laminated photoconductor having a metal grounded flat member coated in turn.

If the photoconductor described above is made drum-shaped, the grounded flat member will include a cylindrical metal core.

U.S. Pat. No. 4,123,270 is significant in that it teaches a method of making a laminated type xerographic imaging member, including a drum. Additionally, this patent teaches the advantages of solvent coating CGLs with or without adhesives (ie, non-pigmented coatings) by using amine solvents or solvent mixtures containing amines.

The particulates forming the CGL are monoazo, disazo or aquaric acid type derivatives, these raw materials being soluble in organic primary amines.

In a first processing step of known reproduction machines of the electrophotographic type, the drum is rotated through a charging station, such as a corona charger, so that the entire surface of the photoconductor drum is coated uniformly and usually at a very high DC. charged to a voltage. The charged drum surface then moves past an imaging station.

In a reproduction machine, the imaging station typically includes an optical system that operates to reflect light from the original document to be reproduced. As a result of electrical discharge curing by light reflected from white or light colored background areas of the document, the drum retains charge only in areas corresponding to darker or less reflective image areas of the document.

This latent image is then toned or coated with toner as the drum passes through a development station. Because the toner is applied to the charged latent image in a reproduction device, this process is referred to as a charged area visualization (CAD) process.

In printers, the imaging station typically includes a laser scanning printer head and an LED array printer head, which typically includes a printer head driven by a binary print data supplied by some type of computer. It is mentioned as a well-known imaging station. Printers normally operate by discharging a drum with the image to be printed. That is, as the printer head normally writes the image to be printed, the latent image will be drawn from the discharge area of the drum. However, the printer can also be configured to write a background, in which case the latent image is diverted from the W field area of the drum.

In either case, this latent image is toned, ie, coated with toner, as the drum passes through the development station. When toner is applied to the discharged latent image of a printer, this process is referred to as a discharged area development (DAD) process.

Was the toner charged by the printer? ! When attached to
This process is also called DAD.

As will be apparent, the present invention has utility in printers or copiers and in CAD or DAD processes. A drum-type photoconductor according to the present invention may be formed, for example, in the form of a hollow aluminum cylindrical extruded or shaped tube. Contains a metal core like a member.

According to a feature of the invention, the metal surface of the core is treated to provide a non-interface reflective surface for an imaging light source, such as a laser scanning imaging station of a printer.

The usual next step in the process of either a copier or a printer is to transfer the main portion of the toner image carried on the drum to a transfer material, preferably a dielectric transfer material such as paper, at a location downstream of the development station. It is to be.

The sheet of transfer material is fed to a transfer station where the vapor is in actual contact with or in close proximity to the drum so as to actually cover the drum and its toner image. This proximity of one side of the web to the drum allows the operation of the toner transfer station to be applied to the other side of the web. There are two known transfer stations: roll transfer stations and corona transfer stations. In either case, a charge is applied to said other side of the vaporizer to attract toner from the drum to said one side of the vaporizer, after which the vaporizer is separated from the drum and conveyed to a fusing station, where the fusing station 3 In the process, the toner is melted onto said one side of the vapor. The drum is typically discharged to remove residual toner in preparation for reuse in the copying process.

The present invention provides a method for making an electrophotographic drum-shaped photoconductor having a low molecular weight crosslinked barrier layer located between an aluminum conductive core member and a charge generating layer, and a drum-shaped photoconductor made by the method. Relating to a photoconductor.

U.S. Pat. No. 3,819,369 describes another copying technique for frost imaging in which a barrier layer of high molecular weight phenoxy or epoxy resin is located between a photoconductive layer and a high positive reduction potential conductive layer. teaches a frost imaging member having a

U.S. Pat. No. 4,579,801 describes the use of a thermoset epoxy as a subbing layer between the support layer and the photoconductive layer.

U.S. Pat. No. 4,485,161 teaches an electrophotographic element having a barrier layer comprised of crosslinked monomers and located between a conductive layer and a photoconductive layer.

The various photoconductive layers of the present invention are formed by a dip coating process. U.S. Pat. No. 4,563.40111 describes a photoconductor imaging member made by Step C, which includes disop coating.

SUMMARY OF THE INVENTION The present invention provides an improved drum-shaped photoconductor and method of making a cough photoconductor. A preferred embodiment of a drum-shaped photoconductor according to the present invention is used in the discharge area development (DAD) process of an electrophotographic laser printer.

The drum-shaped photoconductor according to the invention includes an internal aluminum core, the cylindrical outer surface of which is shaped to a non-specular surface, for example by diamond turning. Speckles of black toner (
In order to minimize this occurrence, the aluminum core is lightly mechanically polished following the diamond turning process. In this way, a non-specular surface is formed and the surface roughness is slightly reduced, which prevents the above-mentioned speckle defects from occurring during continuous use of the drum-shaped photoconductor in a reproduction machine. That is excluded.

The Alcarium core is then cleaned using, for example, a steam fat technique.

A thin barrier with a thickness in the range of 0.05 micrometers/
The adhesive layer is formed on the conditioned surface of the aluminum core by a dip coating process followed by a heat curing process, followed by a heat curing process. Said barrier/
The adhesive layer consists of a resin that is insoluble in amine type solvents. Preferably, the barrier/adhesive layer comprises a crosslinked aliphatic epoxy resin, a crosslinked aromatic epoxy resin, or a thermally crosslinked phenoxy resin.

The charge generating layer is then coated onto the cured barrier/adhesive layer by using a coating ink containing charge generating particulates such as OHSQ, a resin such as toluene sulfonamide resin, and an opiate-containing solvent system. is dip coated. In this dip coating process, the drum is first lowered into a tank of coating ink such that the axis of the drum extends vertically. As the drum is then withdrawn from said dip tank at a controlled vertical rate of movement, air flow means operate to ensure control of the flow of amine vapor solvent leaving the surface of the drum at a location immediately above the dip tank. In a preferred embodiment of the invention, said air flow means are arranged such that the amine vapor leaves the coating ink while the drum is continuously moving vertically upwards from the dip pump. a drying ring having means. The charge generation layer is then heat cured.

An object of the present invention is to control the flow of solvent leaving the wet surface of a Dinop coated drum when the drum is withdrawn from a bulk supply of coating ink. If the flow of the solvent vapor is not controlled, the coated layer may not have the fine grain structure necessary for the proper functioning of the xerographic reproduction device and drying/curing may be done using an oven at high temperatures. It is achieved by this.

The charge transport layer is then coated using a coating ink with transport particles such as DEH, yellow dye, polyester resin, polycarbonate resin and solvent based.
Dip coat the cured charge generating layer. The charge transport layer is then heat cured.2 It is an object of the present invention to provide a drum-shaped photoconductor for use in electrophotographic laser printers. The drum photoconductor contains an aluminum core that is tailored to provide a non-specular reflective surface that allows the drum photoconductor to be used in printers without producing speckled defects. A thin barrier layer can be incorporated into the drum photoconductor.

Yet another object of the present invention is to provide a non-specular surface by means of diamond turning followed by light mechanical polishing, and then to form a thin barrier/adhesive layer on the non-specular surface by a dip coating process. The goal is to make it possible. As a feature of the present invention, the barrier/adhesive layer comprises a crosslinked aliphatic epoxy resin, a crosslinked aromatic epoxy resin, or a phenoxy resin that crosslinks under heat; / Insoluble in the amine solvent used to coat onto the adhesive layer.

The charge generating layer is then dip coated onto the barrier/adhesive layer by using a coating ink containing an amine solvent. As a feature of the present invention, dip coating of the charge generating layer is performed when the drum is drawn from a bulk supply of coating ink. Yet another feature of the present invention includes the use of dry ring type airflow means to control the manner in which the carrier air exits the coating ink. The charge transport layer containing the phonamide resin is then coated onto the charge generating layer. As a feature of the present invention, the charge transport coating ink contains DEW, a polyester resin, and a polycarbonate resin.

The above and other objects and advantages of the present invention will become apparent to those skilled in the art upon reference to the following detailed description with reference to the accompanying drawings. In its preferred monochromatic form, the drum-shaped photoconductor of the present invention is useful in both CAD and DAD copying machines.
It is effective in D laser printers.

The printer shown in Fig. 1 is a D A D copying device, and the process size of the drum-shaped photoconductor is small in relation to the process size of the copying material sheet. This is an example of a device. However, the spirit and scope of the invention is not limited to such small process size drum photoconductors.

This printer uses 215.9 x 279.4 mm (
85 x 11 inches) or 215.9 x 355.
A 6 mm (8.5 x 4 inch) sheet of Baba is passed through a copying process with the short 215.9 mm (8.5 inch) edge as the leading edge, and the two long edges of said sheet are extends in a direction parallel to the process direction.Thus, the process size of the copy material sheet is either 279.4 mm (II inches) or 3556 mm (14 inches).
In the illustrated reproduction apparatus, a drum photoconductor 10 rotates clockwise about a horizontal axis 11 at a substantially constant speed during the reproduction cycle, typically at a surface or process speed of the drum 10. is about 50.8 ari per second (
For example, the axial length of drum 10 may be approximately 254 mm (10 inches) and the circumferential force length may be approximately 127 mm (5 inches), thus 27 mm (2 inches).
Two and a few revolutions of the drum lO are required to process one sheet of 9.4 mm (11 inches) long paver. Next, as is well known to those skilled in the art, First, the outer photosensitive surface of drum 10 is exposed to a relatively high DC voltage as incremental areas of the drum surface move through a charging station defined by corona charger l2.
In this preferred embodiment, but not limited to, the imaging station 13 is charged to a voltage, e.g., 800 volts, and then the charged photoconductor surface passes through the imaging station 13. It includes laser scanning means l4 of known type. Laser scanning means 14 receives the final data to be printed via print data line or bus 15. As a result of the operation of imaging station 13, an electrostatic latent image is formed on photoconductor drum 10 downstream of imaging station l3. As is well known, the laser scanning means 14 operates to discharge or write the area of the drum corresponding to the image to be printed.
This latent image thus consists of the empty drum area. The electrostatic latent image then passes through or near a developer station 16 where toner is applied to the latent image. As mentioned above, since the preferred embodiment is a DAD device, toner is deposited in the discharged areas.

A feature of the invention is the provision of an aluminum core for the drum 1O, which is provided with a non-specular reflective surface for the laser scanning means 14.

As the toned image on the surface of the drum 10 moves toward the transfer station 17, a sheet of barber moves at a speed of, for example, about 2 inches per second, which is equal to the processing speed of the drum 10. from the Baber supply and feed means 18 at speed. The details of construction and arrangement of the vapor supply/feeding means can take a wide variety of forms, as is well known to those skilled in the art. Furthermore, the starting point of the laser scan is set as a function of the Baber feed from the feeding means l8,
It is within the scope of the invention to control, or alternatively to control said means 18 as a function of the progress of the laser scanning process.

Sheets passing through or entering the copying process at a speed of about 2 inches per second pass through a first section 19 upstream of transfer station 17 and a second section 19 downstream of transfer station 17. It follows a generally straight trajectory having a section 20.

When successive copies or printed sheets are made, the sheets are separated from the 215.9 mm (8.5 inch) trailing edge of one sheet and the 215.9 mm (8.5 inch) trailing edge of the next sheet.
It is sequentially fed from the means I8 with a gap of about 25.4 mm (I inch) between the leading energy of 9 mm (8.5 inches).

In the preferred embodiment described above, transfer station 17 includes a corona transfer device 30 and an erase or extinguish lamp 3l. Corona transfer device 30 operates to charge the bottom side of the sheet of transfer material as the sheet moves through transfer station 17 at a speed of approximately 2 inches per second.

As a result, the photoconductor toner image is transferred to the upper surface of the sheet.

After the toner has been transferred to the top surface of the sheet of transfer material, the sheet enters portion 20 of its processing track. In this part of the trajectory, the toner image is e.g.
3, it is melted onto the surface of the sheet. Thereafter, this finished sheet is stacked on the output means.

The surface of the drum-shaped photoconductor IO is then moved to a cleaning station for recycling the copying process.

FIG. 2 shows an enlarged portion of the drum-shaped photoconductor IO shown in FIG. In this figure, the reference numeral 2l designates a hollow cylindrical aluminum core which carries the well-known grounded planar member of a laminated electrophotographic photoconductor. In practice, this core is formed from an extruded aluminum tube with precisely adjusted eccentricity. For example, the radial thickness of the core member 2l may be approximately 1.27G (0.05 inch). During operation of the printer drum photoconductor 10 shown in FIG. 1, the core member 2l is conventionally connected to ground potential.

As a feature of the present invention, the outer cylindrical surface 23 of the core member 2l is processed so as to become a non-specular reflective surface for the laser beam l4 being scanned. For example, the surface 23
is diamond-turned and then lightly polished. Surface treatment of said surface 23 in this manner provides a non-specular reflective surface for the imaging station run of an electronic reproduction machine, and also ensures that areas of the drum that are to remain charged are located on surface 23. This can minimize dot image defects that sometimes occur when undesirably discharged due to non-uniformity. After this surface conditioning step, the core member 2l is cleaned.

Continuous barrier layer 22 (i.e., a layer without any breaks)
is dip coated onto the cylindrical outer surface 23 of the core member 21. As mentioned above, according to the features of the present invention:
The shape of said surface 23 is adjusted prior to coating the barrier N22. Barrier layer 22 is extremely thin, for example about 0.05 micrometers thick.

Barrier layer 22 is of the well-known B type and functions to block current leakage from the highly charged -800 volts DC background region on the surface of CTL 25 to grounded planar member 2l, and prevents the coating of CGL 24 from leaking. ridges, points associated with smoothing effects that may unexpectedly remain on the surface 23 of the core member 21 after the shape of the surface 23 has been adjusted according to the present invention. Alternatively, it includes an electrical insulator or barrier that further minimizes dot image defects in the drum photoconductor by providing humps. Furthermore, the layer 22 is made up of the core member 21 and C
It also functions as an adhesive layer with the GL24. The layer 22
is so thin that the electrical function of the photoconductor in the electrophotographic process shown in FIG. L is not inhibited by the presence of the insulating layer.

As a feature of the present invention, barrier layer 22 is comprised of a cross-linked resin that is insoluble in the solvent used to later coat CGL 24. Preferably, said layer 22 is coated with a coating ink containing an aliphatic epoxy and a crosslinking agent, or an aromatic epoxy and a crosslinking agent, or a coating ink containing a phenoxy that crosslinks after coating under heat.

After the barrier layer 22 is cured to a crosslinked form, a continuous CC,
L24 is dip coated thereon.

CGL24 is also a very thin layer, with a thickness of about 0.
It is in the range of 25 micrometers.

As a feature of the present invention, CGL 24 is coated from a solvent containing a resin, such as a toluene sulfonamide resin, hydroxysquaryl+ charge generating particulates, and an amine solvent system. Another feature of the invention {hence, CC;L
In order to preserve the electrical properties of the CCL 24 when the CCL 24 is disob-coated onto the barrier layer 22, evaporation of the solvent from the wet coating is performed using an air flow means, such as a dry ring air flow means. After the CGL 24 is cured using a concomitantly controlled method, a continuous CTL 25 is coated thereon by a dip coating process.The CTL 25 is a relatively thick layer, with a thickness of approximately 22.5 mm. It is in the range of 50 micrometers. In a preferred embodiment of the invention, the CTL 25 is coated with a diffusive material containing polycarginate resin, polyester resin, DEH transport particles, and a solvent.

FIG. 3 shows the aluminum core 2 of the drum-shaped photoconductor 10.
1, one end 42 of said core 21 is spaced a short distance from a plastic plug 35 which is useful during dip coating of the drum 10 as well as its handling when the drum is made according to the invention.

Although not limited thereto, core member 21 typically has an overall length 36 of approximately 249.95 inches (9.84 inches).
So, the inner diameter 37 is approximately 38.6 mm (1.52 inches),
The outer diameter 38 is approximately 39.9ξ (1.57 inches).

The central dimension 39 within dimensions 36 has a typical length of 235.9 mm (9.29 inches) and is the surface of an electrically actuated drum in the electrophotographic process shown in FIG. stipulates. This cylindrical surface 39 is generally non-specular with respect to the laser scanning imaging station 14 shown in FIG. Adjusted to receive layer 22.

The roughening of the main central portion 39 of the core member 2l according to the present invention provides two important photoconductor properties. First, the surface 39 of the core 21 must be non-specular to the imaging station of the reproduction machine in which the photoconductor is used. In this way, a laser beam scanned at an imaging station, for example a xerographic printer, is clearly not reflected from the core member 2l.

This eliminates image interference patterns and the surface portion 39 must be non-specular, but this requires that the surface be roughly adjusted in a certain range.

However, according to a second aspect of the invention, this surface roughness is such that it has a high degree of tendency to discharge a portion of the surface of the drum 10, thereby creating dot defects in the reproduced image and/or background. It must not generate a local electric field. This latter property of surface portion 39 is particularly important when barrier layer 22 of drum photoconductor 10 is a very thin layer, as in the preferred embodiment of the invention.

In a typical embodiment of the present invention, but not limited to this embodiment within the broad spirit and scope of the present invention, the surface roughness (Ra) of the portion 39 of the core member 2l is Approximately 0. It was 15 micrometers (6 microinches). In addition, the height (Ry) from peak to valley of the surface roughness does not exceed about 1.25 micrometers (50 microinches), and the average distance between peaks on the average line of surface roughness. (Sm) did not exceed approximately 0.1 mm (0.004 inch).

3 coating layers 22. Before and after each of 24 and 25 is shaped into the aluminum core member 21, the core member 21 is manually or automatically handled by a cylindrical hard plastic plug 35. This eliminates the possibility of physical contact that would contaminate the outer surface of the core member 2I.

As will be described below with reference to FIG. located above. Thereby, the lower end 42 of the core member 21 is sealed or sealed.

As a result, the coating ink is not wasted by coating the cylindrical inner surface of the core member 21 unnecessarily. Since the cylindrical coating tank shown in FIG. 5, which will be described later, is slightly larger in diameter than the drum-shaped photoconductor IO, a very small amount of coating ink is required in the tank 51 in order to effectively coat the vertical length of the drum. All you have to do is put the . According to such features of the present invention, a large cost reduction is realized.

As described below with respect to FIG. 5, the other end 4 of the core member 21
3 is inserted inside the end 43 of the core member and is then held by a spreading mandrel, not shown, which expands to frictionally hold the core member as it moves vertically during dip coating. Plug 35 includes a cylindrical portion 40 that frictionally fits within the inner diameter 37 of the end 42 of the core member. Once the plug 35 is attached to the end 42 portion of the core member 21, the plug 35 can be manually or
It can be handled by a robot tool, not shown, which cooperates releasably with an annular groove 41 formed in the .

In this manner, the core member 21 can be manually transported between, for example, a discontinuing industrial station and a curing oven as shown in FIG.

In a preferred embodiment, a curing furnace support (not shown) for the core member 21 is provided with a core overlying the plug 35 and the core member end 42 when the plug 35 and the core member end 42 are oriented at the vertically upper end of the core member. It includes a pair of closely spaced and upwardly extending metal bins into which members 2l are inserted. These two wooden bottles fit tightly into the inner diameter of the core member 21 and function to support the core member during heat curing. Preferably, the plug 35 is removed during the heat curing cycle and reinserted into the upper end 42 of the core member 21 after the core member has cooled. In the embodiment using the loposot of the invention, the plug 35 did not include an annular recess 4l, but was rather shaped in the form of a smooth plug. The robotic device included a flared mandrel that engaged the cylindrical inner surface of the end 43 of the core.

The robotic device included a movable rond extending downwardly through the center of core member 21. This rod was used to push the smooth plug 35 out of the core end 42 before placing the core member into the curing oven. Thereafter, after heat curing the coating layer on the core member 21, the robotic device re-engaged and forced the core member onto another plug 35 before coating another layer onto the core member.

After the drum-shaped photoconductor IO has been produced according to the invention, the two open ends 42, 43 of the cylindrical core member 2l are provided with, for example, annular plastic or metal drive gear support means (not shown). and an idle bearing support means. These two means allow the drum 10 to be mounted inside the reproduction apparatus shown in FIG. 1 and to apply rotational forces to the drum 10, as is well known to those skilled in the art. It becomes like this. Furthermore, when metallic or electrically conductive drive means and/or hair ring means are used, these means provide electrical contact to the grounded planar member or core member 21 of the drum-shaped electrical conductor 10. can be used for The disob coating of the drum-shaped photoconductor lO is
The annular strip of core member 21 adjacent its end 43 is left uncoated. Brush means or similar electrical contact means may also be used to provide electrical contact to the core member 21 through this uncoated strip.

In a preferred embodiment of the present invention, barrier layer 22, CGL 24 and CTL 25 are disop coated with a coating ink having the following precepts to achieve specially specified coating thicknesses and core pull rates: Ta.

The coating ink for dip coating the barrier layer 22 is approximately 0.4% by weight epoxy resin under the trademark Epon 1001 and approximately 0.1% by weight under the trademark Versamid 150.
% by weight of polyamide and about 99.5% by weight of tetrahydrofuran (THF)? It contained eight drugs.

In this barrier layer preparation method, the polyamide component contains a crosslinking component for the epoxy component. Crosslinking of the epoxy occurs during the heat curing cycle of the barrier layer. According to a feature of the invention, the resulting barrier layer is insoluble in the highly active amine solvent system used to later coat the CGL onto the crosslinked barrier layer. It is. Both crosslinked aliphatic epoxies and crosslinked aromatic epoxies can be used according to this aspect of the invention. As an alternative to the use of crosslinked epoxies, phenoxy resins that crosslink without a crosslinking component during the heat curing cycle for the barrier layer are recommended.

This feature of the invention allows the extremely thin barrier layer 22 to be operated in a well-known manner as an integral part of the finished drum photoconductor 10, yet the barrier layer 22 is then dip coated with CGL 24 and cross-linked. The coated barrier layer 22 does not dissolve while being exposed to the highly active CGIj carrier system.

The coating ink dip-coated with CGL24 contains about 1.2% by weight of hydroxysquarerium (OHSQ) charge-generating fine particles and about 4.8% by weight of
A toluene sulfonamide resin with the trademark Ketjen Fleχ, about 7.5% by weight of a pyrolidine amine solvent, about 9.4% by weight of a morpholine amine solvent, and about 77.1% by weight of THF. Ta.

The coating ink dip-coated with CTL25 contains approximately 76.7% by weight THF and approximately 0.2% by weight.
A yellow dye whose i'lJI is Savinyl Yellow, about 1.2% by weight of a polyester resin whose trademark is PE-200, and about 12.6% by weight of a polyester resin whose trademark is M P
Voycarbonate resin which is G3408 and about 943
Weight% diethylamine benzaldahyde (dieth
laminobenzaldahyde) (D E
H) 1,1-diphenylhydrazone (
diphenylhydrazone) and trace amounts of a polydimethylsiloxane silicone fluid whose trademark is DC-200.

It can be seen that the formulation described above results in a certain proportion of solids within the coating ink. Within the scope and spirit of the invention, the percentage of solids in the barrier layer, CGL and CTL coating inks can be varied as desired. In general, it is found that as the proportion of solids in a given coating ink increases, the rate of withdrawal of the drum cylinder from the coating bath must be reduced to achieve the same coating thickness. . This relationship is shown in FIG. Although Figure 4 shows the relationship between percent solids and retraction rate as a typical linear function, this relationship is typically not a linear function and varies depending on the precepts chosen for the coating ink. sell.

After each layer 22, 24, 25 of drum 10 is dip coated and before the next layer is dip coated, the drum is placed in an oven for curing. Typical curing cycles for these layers include barrier layer 22 and CG
For both L24, it is about 30 minutes at about 100 degrees,
For CTL25, it is about 60 minutes at about 100 degrees.

FIG. 5 shows a preferred dip coating station according to the invention. Although the coating station is configured to coat only one core member 21 at a time, the dip coating means shown in FIG. 5 may be replicated multiple times to coat multiple core members at the same time. In FIG. 5, the core member 2l
is shown as being in the process of moving upwardly from a metal cylindrical dip tank 51, as indicated by arrow 50. For simplicity of illustration, the expanding mandrel and associated loposot means supporting the end 43 of the core member 21 as well as the plug 3 of FIG. 3 sealing the end 42 of the core member
5 is not shown. The speed of this upward movement 50 is related to the desired coating thickness as well as the percentage of solids present in the coating ink 52 provided as described above with respect to FIG.

It will be appreciated that when dinobu coating the CGL 24 and CTL 25, the core member 2l is covered with a previously cured coating layer. However, for convenience, these disob coating operations are performed on the core member 2.
It is referred to only as a dip coating of 1.

The inner diameter of the Dinopukunku 5L is approximately 3 in the outer diameter of the core member 21.
9.9 mm (1.57 inches) compared to approximately 50
．． It is 8 mm (2 inches). In this way, the core member 2
1 fits tightly within the Dinobu tank 51, so that a very small amount of barrier layer, CGLb or CTL coating ink 52 only needs to be placed in the tank 5l. Since the core member 21 is closed or sealed at its opening 42, this small amount of coating ink 52 is absorbed as the core member 21 moves downwardly in the tank 51 and as the core member moves downwardly through its downward movement. When it reaches the lower end, it quickly rises inside the kunk 51. In this way, the coating ink is supplied to all parts of the end 43 of the core member except for the top ring-shaped part. It takes almost no time. That is, core member 21 begins upward movement 50 almost immediately after said downward movement reaches its lower limit.

As the core member 21 is pulled up from the dip pump 5l, the core member 21 moves upward, so that the tank 5
It can be seen that the level of coating ink in 1 is decreasing relative to the upwardly moving core member 21 in the preferred embodiment of the invention. The speeds are approximately 1.2 m (4, ft)/min for dip coating barrier layer 22, 0.6 m (2 ft)/min for dip coating CC;L24, and 0.6 m (2 ft)/min for dip coating CTL25. 0.4 for dip coating
2 meters (1.4 feet)/minute.

FIG. 5 also shows a drying ring suitable for use in coating CGL24. For more information,
Dip tank 51 is hermetically sealed within a large metal cylindrical tank 53 whose bottom end 54 is closed or sealed. The bottom of the tank 53 is provided with one or more conduits 55 which are connected to a source of negative pressure or vacuum.

The dimple tank 5l has an annular donut-shaped support means 56.
Said support means 56 is generally centrally located within the tank 53 and includes a plurality of airflow passages 57 provided in a symmetrical pattern around the circumferential surface of said means 560. As a feature of the invention, the airflow means 57 ensures uniform downward air flow around the dimple tank 5l.The upper end of the dimple tank 53 is formed by an annular toroidal plug supporting a drying ring 59 according to the invention. It is closed by member 58. The drying ring means 59 is
More specifically, the drying ring means 59 is arranged in such a way as to ensure that a laminar flow of air flows downwardly around the core member 21 while the core member 21 is being raised. It includes a metal cylindrical body 60 attached to the cylindrical body 60. The length of the cylindrical body 60 in the axial direction is approximately 76.2 mm (
3 inches) and has an inner diameter of approximately 50.8 mm (2 inches). In this way, the inner surface of the cylindrical body 60 and the core member 2
The uprag member 58 , between which a thin cylindrical air space 64 is formed, is formed with an inner closed annular cavity 62 located adjacent to its upper flat surface 65 . ing. Cavity 62 is connected to the atmosphere by one or more conduits 63. The term atmosphere as used herein includes the use of inert gases such as nitrogen, the use of nitrogen being preferred for coating hot spots, according to the present invention. The flow of air from conduit 63 to cavity 62 is such that a uniform pressure is maintained around cavity 62. In a preferred embodiment of the invention, the air flow into cavity 62 is approximately 2
The inner circular wall of cavity 62, maintained to be 5II cubic feet, is formed by a porous annular ring 66 with uniform porosity around its circumference, such as a porous polypropylene film. 59, three coatings 22, 211. on the core member 21; It is effective in all 25, but especially. When coating a CGL of a formulation according to the invention, i.e. OHSQ in solution in coating ink 52 containing an amine solvent system.
It has been found that there is great utility in dip coating formulations with transport particles.

The inventor of the present invention has discovered that the CCL coating ink as described above requires that the amine solvent leave the coating ink wet and that the amine vapor does not impinge on the moist surface of the core member 21 moving upward. I discovered that. In the inventor's experience, CGL's OHSQWl
The particles do not switch to their solid state, and as a result,
In the copying machine shown in FIG. 1, there is a possibility that poor electrical effects will occur.

When the drying ring means 59 according to the invention is used, a downward laminar flow of the amine solvent vapor is generated within the cylindrical space 64 and all parts of the CGL are properly switched into a state of mass. The flow rate is equalized around the core member 21 as described above, and this laminar flow is directed parallel to the axis of the core member.

As will be apparent to those skilled in the art, the required non-specular surface of the core member 21, such as a preferred Ra of 0.15 micrometers and a preferred Ra of 1.5 micrometers, as described above, will be appreciated by those skilled in the art.
Various surface treatment means may be employed to create a surface with a surface diameter of 25 micrometers or less, and a Sm of about 0.1 millimeter or less.

The inventors have found that diamond rotary machining followed by light polishing is a suitable means of surface treatment. Figures 6 and 7 show two such means. In Figure 6, the core member 2l is mounted on a horizontal axis 9I and driven at a high speed, for example about 1800 rpm.
The diamond cutting tool 92 engages with the surface of the core member 2l, and the diamond cutting tool 92L applies the surface treatment to the core member, which moves in the axial direction at a speed of about 254 centimeters (10 inches) per 3 seconds. The core member is fed to the orthosis shown in FIG. 7, in which the core member is mounted on a horizontal axis 93 and driven at a low speed of about 100 rpm, e.g.
A section 94 of a thin abrasive synthetic rayon cloth under the trademark oth and having a width of approximately 25.4 centimeters (10 inches) measured parallel to the axis of the core member 21 is wrapped around the bottom of the core member 21. The cloth portion 94 is attached to the core member 2.
However, the fabric is wound from the supply spool 95 onto the take-up spool 96 during each treatment of one or more core members 21. The Ra, Ry and Sm defined above for the surface of the core member 21 are achieved by the preferred embodiment of the present invention.

Although the present invention has been described above with reference to preferred embodiments of the present invention, those skilled in the art will be able to make other embodiments within the spirit and scope of the present invention by learning the teachings of the present invention. What you can recall is probably fleeting.

Accordingly, the invention should be limited only by the scope of the claims.

[Brief explanation of drawings]

FIG. 1 shows a DAD with a drum-shaped photoconductor according to the present invention.
FIG. 2 is an enlarged view showing the layer structure of the drum-shaped photoconductor of FIG. 1; FIG. 3 shows the aluminum core of the drum-shaped photoconductor; Figure 4 shows the overall relationship between the proportion of solids in the coating ink and the withdrawal rate from the supplied coating ink in the dip coating process according to the invention. 5 shows a dip coating station according to the invention, and FIG. and FIG. 7 are simplified diagrams respectively showing the diamond rotation machining of the aluminum core of a drum-shaped photoconductor and the subsequent light surface polishing. ... Corona charger 13 ... Imaging station l4 ... Laser scanning means l6 ... Development station I7 ... Transfer station 18 ... Sheet supply means 22 ... Barrier layer 23 ... Cylindrical outer surface 24...C G L 25...CT
L30...Corona transfer device 5■...Disobtank (1 other person) FIG. 2. FIG. l. FIG. 4.

Claims (1)

[Claims] 1) A method for manufacturing a drum-shaped photoconductor for use in an electrophotographic copying device, comprising: providing a cylindrical aluminum core; and changing the shape of the cylindrical outer surface of the core to a non-specular reflective surface. dip coating a thin, fluid barrier/adhesive layer containing a resin that is insoluble in an amine solvent when cured onto the cylindrical outer surface, and forming a cured barrier that is insoluble in an amine solvent; / heat curing said barrier/adhesive layer to form an adhesive layer; dip coating a fluid charge generating layer onto said cured barrier/adhesive layer using a coating ink containing an amine solvent; thermally curing the charge generation layer to form a cured charge generation layer; dip coating a fluid charge transport layer onto the cured charge generation layer; A method of making a drum-shaped photoconductor comprising the step of heat curing a transfer layer. 2) The method of claim 1, wherein air is used to create a laminar flow of amine solvent vapor away from the fluidic charge generating layer as the core is withdrawn from a bulk supply of charge generating coating ink. A method of manufacturing a drum-shaped photoconductor comprising the step of providing flow control means. 3) The method of claim 2, wherein the fluid charge generating layer contains OHSQ charge generating particulates. 4) The method of claim 3, wherein the fluidic charge transport layer contains DEH charge transport particulates. 5) A method according to claim 4, in which the barrier/
A method of producing a drum-shaped photoconductor in which the adhesive layer contains an epoxy or phenoxy resin that is crosslinked under heat and becomes insoluble in an amine solvent when cured. 6) A drum-shaped photoconductor produced by the method according to claim 5. 7) An electrophotographic printer having a drum-shaped photoconductor and a laser-scanning imaging station, wherein the drum-shaped photoconductor comprises a cylindrical photoconductor having a non-specular reflective cylindrical outer surface of the laser-scanning imaging station. an aluminum core; a thin barrier/adhesive layer dip-coated onto said cylindrical outer surface and containing a resin insoluble in an amine solvent; and a coating ink containing an amine solvent applied onto said barrier/adhesive layer. An electrophotographic printer comprising: a dip-coated charge generation layer; and a charge transport layer dip-coated on the cured charge generation layer. 8) The printer according to claim 7, wherein the charge generation layer contains OHSQ charge generation particles. 9) The printer of claim 8, wherein the charge transport layer contains DEH charge transport particulates. 10) The printer of claim 9, wherein the barrier/adhesive layer contains a cured epoxy resin or a cured phenoxy resin that, when cured, becomes insoluble in amine solvents. 11) A method of manufacturing a drum-shaped photoconductor for use in an electrophotographic reproduction device, comprising: providing a cylindrical, electrically conductive metal core, and providing a surface roughness (Sm) of about 0.15 micrometers; preparing the outer surface of the core to provide a non-specular reflective surface by applying a fluid barrier layer to the cylindrical outer surface containing a resin insoluble in an amine solvent and having a thickness of about 0.05 micrometers when cured; Dip coat and then cure a fluidic charge generating layer approximately 0.20 micrometers thick.
dip coating onto the cured barrier layer using a coating ink containing an amine solvent and then heat curing to form a fluidic charge transport layer about 22.50 micrometers thick on the cured charge generating layer. 1. A method of making a drum-shaped photoconductor comprising the steps of dip coating and then heat curing. 12) The method of claim 11, wherein the cylindrical outer surface of the core has a peak-to-valley height (Ry) of about 1.25.
A method for manufacturing a drum-shaped photoconductor characterized in that it does not exceed a micrometer. 13) A method according to claim 12, characterized in that the mean spacing between peaks in the mean line (Sm) of the cylindrical outer surface of the core does not exceed about 0.1 mm. A method of manufacturing a shaped photoconductor. 14) The method of claim 13, wherein the air flow rate is for generating a laminar flow of amine solvent vapor leaving the fluidic charge generating layer as the core is withdrawn from the bulk supply of charge generating coating ink. A method of manufacturing a drum-shaped photoconductor comprising the step of providing a control means. 15) The method according to claim 14, wherein the resin of the fluid barrier layer is a drum-shaped resin selected from the group consisting of aliphatic epoxy and its crosslinking agent, aromatic epoxy and its crosslinking agent, or phenoxy. Method of manufacturing electrical conductors. 16) The method of claim 14, wherein the resin of the fluid barrier layer is an aliphatic epoxy and its crosslinking agent. 17) The method of manufacturing a drum-shaped photoconductor according to claim 14, wherein the resin of the fluid barrier layer is an aromatic epoxy and its crosslinking agent. 18) The method of claim 14, wherein the resin of the fluid barrier layer is a phenoxy resin. 19) The method of claim 18, wherein the fluid charge generating layer contains OHSQ charge generating particulates and toluene sulfonamide resin. 20) The method of claim 19, wherein the fluid charge transport layer comprises DEH charge transport particulates, a polyester resin, and a polycarbonate resin. 21) The method of claim 20, wherein the fluid charge transport layer contains a yellow dye. 22) A drum-shaped photoconductor produced by the method according to claim 21. 23) A method of manufacturing a drum-shaped photoconductor for use in an electrophotographic printer having a laser-scanning imaging station, comprising: providing a cylindrical metal core; an Sm parameter of about 0.15 micrometer; about 1.2;
adjusting the shape of the cylindrical outer surface of the core to have an Ry parameter of no greater than 5 micrometers and an Sm parameter of no greater than about 0.1 millimeter, and a barrier layer having a thickness of about 0.05 micrometer; a charge generating layer having a thickness of about 0.20 micrometers and coating the cured barrier on the cured barrier and having a thickness of about 22.0 micrometers.
A method of making a drum photoconductor comprising the step of coating a charge transport layer of 50 micrometers on the cured charge generating layer. 24) The method of claim 23, wherein the barrier layer is selected from the group consisting of aliphatic epoxy and its crosslinker, aromatic epoxy and its crosslinker, or phenoxy. How to manufacture. 25) The method of claim 24, wherein the resin of the barrier layer is an aliphatic epoxy and its crosslinker. 26) A method for producing a drum-shaped photoconductor according to claim 24, wherein the resin of the barrier layer is an aromatic epoxy and its crosslinking agent. 27) The method of manufacturing a drum-shaped photoconductor according to claim 24, wherein the resin of the barrier layer is a phenoxy resin. 28) The method of claim 24, wherein the charge generating layer contains OHSQ charge generating particulates and toluene sulfonamide resin. 29) The method of claim 28, wherein the charge transport layer contains DEH charge transport particulates, a polyester resin, and a polycarbonate resin. 30) The method of claim 29, wherein the charge transport layer contains a yellow dye. 31) A drum-shaped photoconductor produced according to claim 30. 32) In an electrophotographic printer having a laser scanning imaging station and a drum photoconductor, the drum photoconductor has an Sm parameter of about 0.15 micrometers, about 1.2
a cylindrical metal core having an outer surface with an Ry parameter of no greater than 5 micrometers and an Sm parameter of no greater than about 0.1 millimeter, and a thickness of about 0.0 mm;
a barrier layer on the outer surface of the core that is 5 micrometers; a charge generation layer on the barrier layer that is about 0.20 micrometers thick; and a charge generation layer on the barrier layer that is about 22.50 micrometers thick. and a charge transport layer on the charge generation layer. 33) The printer of claim 32, wherein the barrier layer contains a resin selected from the group consisting of aliphatic epoxy and its crosslinking agent, aromatic epoxy and its crosslinking agent, or phenoxy. . 34) An electrophotographic printer according to claim 32, wherein the resin of the barrier layer is an aliphatic epoxy and a crosslinking agent thereof. 35) An electrophotographic printer according to claim 32, wherein the barrier layer is an aromatic epoxy and its crosslinker. 36) The electrophotographic printer according to claim 32, wherein the resin of the barrier layer is a phenoxy resin. 37) The electrophotographic printer of claim 32, wherein the charge generation layer includes OHSQ charge generation particulates and toluene sulfonamide resin. 38) The electrophotographic printer of claim 37, wherein the charge transport layer contains DEH charge transport particulates, a polyester resin, and a polycarbonate resin. 39) The electrophotographic printer of claim 38, wherein the charge transport layer contains a yellow dye.