JP6217489B2 - Cleaning member, charging device, unit for image forming apparatus, process cartridge, and image forming apparatus - Google Patents

Description

  The present invention relates to a cleaning member, a charging device, a unit for an image forming apparatus, a process cartridge, and an image forming apparatus.

  In an image forming apparatus using an electrophotographic method, first, the surface of an image carrier made of a photosensitive member or the like is charged by a charging device to form a charge, and an electrostatic latent image is formed with a laser beam or the like that modulates an image signal. Form. Thereafter, the electrostatic latent image is developed with the charged toner and a visualized toner image is formed. Then, the toner image is electrostatically transferred to a transfer medium such as a recording sheet via an intermediate transfer body or directly, and fixed on the transfer medium to obtain an image.

In the image forming apparatus, a cleaning member for removing foreign matters attached to the surface of the constituent member is disposed.
For example, in Patent Document 1, a core body and an elastic layer arranged in a spiral shape on the outer peripheral surface of the core body are provided, and the thickness of the elastic layer at the center in the spiral width direction is Ta (mm). Conditional expression (A1): 1 <Tb / Ta <1.75 and conditional expression (A2): 0.5 <Ta <4, where Tb (mm) is the thickness at both ends in the spiral width direction of the elastic layer. 0.0, a cleaning member for an image forming apparatus is disclosed.

JP 2011-164568 A

  An object of the present invention is to provide a cleaning member in which exfoliation of the foamed elastic layer from the core body is suppressed and the cleaning property at the end in the longitudinal direction of the foamed elastic layer is improved.

In order to achieve the above object, the following invention is provided.
The invention of claim 1 is a foamed elastic layer in which a strip-shaped foamed elastic member is spirally wound from one end to the other end of the core body on the outer peripheral surface of the core body. The length of the foamed elastic layer in the circumferential direction of the core body at one or both of the longitudinal ends of the foamed elastic layer is the circumferential direction of the core of the foamed elastic layer in a region other than the end part. A foamed elastic layer having a circumferentially extending portion extending in the circumferential direction of the core body from the longitudinal end of the foamed elastic layer so as to be longer than the length of the core, and the core body and the foamed elastic layer. A cleaning member comprising an adhesive layer to be bonded.
The invention according to claim 2 is characterized in that the foamed elastic layer has a circumferential length X1 of the circumferential extension portion at one or both of the longitudinal ends of the foamed elastic layer Y, and a circumferential length of the core body Y. When the length in the circumferential direction of the core of the foamed elastic layer in the region other than the end portion is R1, the relationship of (Y−R1) × 10% ≦ X1 ≦ (Y−R1) × 90% is satisfied. The cleaning member according to claim 1.
According to a third aspect of the present invention, a region of the surface of the foamed elastic layer that is in contact with the outer peripheral surface of the core body through the adhesive layer is disposed on a surface facing the outer peripheral surface of the core body. The cleaning member according to claim 1 or 2 , wherein the area is an area ratio per unit area of 40% or more.
Invention of Claim 4 is provided with the notch part or the level | step-difference part in the outer peripheral surface of the boundary part of the said circumferential direction extension part of the said foaming elastic layer , Any one of Claims 1-3 . Cleaning member.
According to a fifth aspect of the present invention, the surface of the foamed elastic layer that adheres to the outer peripheral surface of the core body via the adhesive layer in at least the circumferentially extending portion is formed of a non-foamed layer. cleaning member according to any one of claim 4.
The invention of claim 6 includes a charging member for charging the member to be charged, said is placed in contact with the surface of the charging member, to any one of claims 1 to 5 for cleaning the surface of the charging member A charging member.
According to a seventh aspect of the present invention, there is provided a process cartridge that includes at least the charging device according to the sixth aspect and is detachable from the image forming apparatus.
According to an eighth aspect of the present invention, there is provided an image carrier, the charging device according to the sixth aspect, a charging means for charging the surface of the image carrier, and a latent image on the surface of the charged image carrier. A latent image forming unit to be formed; a developing unit that develops the latent image formed on the image holding member with a developer containing toner to form a toner image; and a transfer unit that transfers the toner image to a transfer target. An image forming apparatus.
The invention according to claim 9 is the cleaning according to any one of claims 1 to 5 , wherein the member to be cleaned is disposed in contact with the surface of the member to be cleaned, and the surface of the member to be cleaned is cleaned. A unit for an image forming apparatus.
According to a tenth aspect of the present invention, there is provided a process cartridge that includes at least the unit for the image forming apparatus according to the ninth aspect and is detachable from the image forming apparatus.
The invention of claim 11 is an image forming apparatus comprising the unit for an image forming apparatus according to claim 9 .

According to the first and second aspects of the present invention, the length of the foamed elastic layer in the circumferential direction of the foamed elastic layer at both ends in the longitudinal direction of the foamed elastic layer is such that the length of the foamed elastic layer in the region other than the end. As compared with the case where the length of the core body is the same as the length in the circumferential direction, there is provided a cleaning member in which the peeling of the foamed elastic layer from the core body is suppressed and the cleaning property at the longitudinal end of the foamed elastic layer is improved. Is done.

According to invention of Claim 3, the cleaning member by which peeling in the edge part of a foaming elastic layer is suppressed compared with the case where the said area ratio is less than 40% is provided.

According to invention of Claim 4, the cleaning member with the high cleaning property in an edge part is provided compared with the case where the said notch part or level | step-difference part is not provided.

According to the invention of claim 5 , there is provided a cleaning member that does not have the non-foamed layer and that suppresses peeling at the end of the foamed elastic layer as compared with the case where the circumferential extension is not compressed in the thickness direction. Provided.

According to invention of Claim 6 , the length of the said elastic body in the circumferential direction of the said foaming elastic layer in both the longitudinal direction edge parts of a foaming elastic layer is the said core of the said foaming elastic layer in the area | regions other than the said edge part. Compared with the case where a cleaning member having the same length as the circumferential direction of the body is applied, the charging performance is prevented from being deteriorated due to poor cleaning of the charging member due to peeling of the foamed elastic layer from the core of the cleaning member or poor cleaning. A unit for an image forming apparatus is provided.

According to invention of Claim 7 , 8 , the length of the circumferential direction of the said core body of the said foaming elastic layer in both the longitudinal direction edge parts of a foaming elastic layer of the said foaming elastic layer in the area | regions other than the said edge part. A process cartridge in which image defects due to peeling of the foamed elastic layer from the core and cleaning defects in the cleaning member are suppressed as compared with the case where a cleaning member having the same circumferential length as the core is applied. A forming apparatus is provided.

According to the invention of claim 9 , the length of the foamed elastic layer in the circumferential direction of the foamed elastic layer at both ends in the longitudinal direction of the foamed elastic layer is such that the core of the foamed elastic layer in the region other than the end. Compared to the case where a cleaning member having the same length as the circumferential direction of the body is applied, a unit for an image forming apparatus that suppresses the deterioration of the performance due to peeling of the foamed elastic layer from the core or poor cleaning in the cleaning member Is provided.

According to invention of Claim 10 , 11 , the length of the circumferential direction of the said core body of the said foaming elastic layer in both the longitudinal direction edge parts of a foaming elastic layer of the said foaming elastic layer in the area | regions other than the said edge part. Provided are a process cartridge and an image forming apparatus in which image defects caused by deterioration in performance due to poor cleaning of a member to be cleaned are suppressed as compared with a case where a cleaning member having the same circumferential length as the core is applied. .

It is the schematic which shows the cleaning member which concerns on this embodiment. It is the schematic which expands and shows the one end part of the cleaning member which concerns on this embodiment. It is an expanded view which shows the foaming elastic member which comprises the foaming elastic layer of the cleaning member which concerns on this embodiment. It is the schematic which shows the AA line cross section of the cleaning member shown in FIG. It is the schematic which shows the BB line cross section of the cleaning member shown in FIG. It is an expanded view which shows the other example of the foaming elastic member which comprises the foaming elastic layer of the cleaning member which concerns on this embodiment. It is an expanded view which shows the other example of the foaming elastic member which comprises the foaming elastic layer of the cleaning member which concerns on this embodiment. It is the schematic which shows an example of the cut | notch part provided in the edge part of the cleaning member which concerns on this embodiment. It is the schematic which shows an example of the manufacturing method of the cleaning member which concerns on this embodiment. 1 is a schematic configuration diagram illustrating an electrophotographic image forming apparatus according to an embodiment. It is a schematic block diagram which shows the process cartridge which concerns on this embodiment. FIG. 12 is a schematic configuration diagram in which a peripheral portion of the charging member (charging device) in FIGS. 10 and 11 is enlarged. It is the schematic which shows an example of the conventional cleaning member.

  Embodiments that are examples of the present invention will be described below. In addition, the same code | symbol may be provided to the member which has the same function and effect | action through all the drawings, and the description may be abbreviate | omitted.

  The target (member to be cleaned) to be cleaned using the cleaning member according to the present embodiment is not particularly limited, but is suitable as a cleaning member for an image forming apparatus. For example, a charging roll, a transfer roll, an intermediate transfer body It is suitably used as a cleaning member. Hereinafter, as a representative example, a cleaning member for cleaning a roll-shaped charging member (charging roll) will be mainly described.

(Cleaning member)
The cleaning member according to the present embodiment includes a core body and foam elasticity in which a strip-shaped foam elastic member is spirally wound from one end to the other end of the core body on the outer peripheral surface of the core body. The core of the foamed elastic layer in a region other than the end of the foamed elastic layer in the circumferential direction of the foamed elastic layer at one or both of the longitudinal ends of the foamed elastic layer. A foamed elastic layer having a circumferential extension extending in the circumferential direction of the core body so as to be longer than the circumferential length of the core body, and an adhesive layer for bonding the core body and the foamed elastic layer. Configured.

  FIG. 13 schematically shows an example of a conventional cleaning member for an image forming apparatus, in which a band-shaped (strip-shaped) foamed elastic member 220 is spirally wound around the outer peripheral surface of a core body 210 and is bonded to an adhesive layer. The end portions 220A and 220B are compressed in the thickness direction to prevent peeling. Therefore, the area of the uncompressed portion is reduced as compared with the portions other than the end portions 220A and 220B. As a result, the cleaning performance of the end portions 220A and 220B tends to be inferior.

  If the compression region is set outside the longitudinal region where cleaning is required, it is not necessary to use inferior cleaning portions of the end portions 220A and 220B. However, for example, it is difficult to secure an area to be compressed in the thickness direction necessary to prevent the spiral foamed elastic layer from peeling off from the core while maintaining the axial length according to the small printer.

  FIG. 1 is a schematic diagram illustrating an example of a cleaning member for an image forming apparatus according to the present embodiment. FIG. 2 is an enlarged schematic view showing one end portion of the cleaning member according to the present embodiment. FIG. 3 is a development view showing the foamed elastic member constituting the foamed elastic layer of the cleaning member according to the present embodiment. FIG. 4 is a schematic view showing a cross section taken along line AA of the cleaning member shown in FIG. 1, that is, a surface obtained by cutting the foamed elastic layer in the vicinity of the central portion of the cleaning member along the circumferential direction of the core body. FIG. 5 is a schematic view showing a cross section taken along the line B-B of the cleaning member shown in FIG. 1, that is, a surface obtained by cutting the foamed elastic layer near one end of the cleaning member along the circumferential direction of the core body.

  A cleaning member (hereinafter simply referred to as “cleaning member”) 100 for an image forming apparatus according to the present embodiment may be referred to as a roll-shaped member (“cleaning roll”) as shown in FIGS. And a core body 110, a foamed elastic layer 120, and an adhesive layer 130 for bonding the core body 110 and the foamed elastic layer 120 to each other.

  The foamed elastic layer 120 is formed on the outer peripheral surface of the core body 110 by spirally winding the strip-shaped foamed elastic member 120 shown in FIG. 3 from one end of the core body 110 to the other end. Specifically, the foamed elastic member 120 is disposed in a state where the foamed elastic member 120 is spirally wound with an interval from the vicinity of one end of the core 110 to the vicinity of the other end using the core 110 as a spiral axis. The length of the foamed elastic layer 120 in the circumferential direction of the core body 110 at both ends in the longitudinal direction is longer than the length of the foamed elastic layer 120 in the circumferential direction of the core body 110 in the region 120C other than the end part (circumference). Direction extension portions) 120A and 120B are provided.

As shown in FIG. 3, the strip-shaped foamed elastic member 120 constituting the foamed elastic layer 120 (hereinafter sometimes referred to as “strip”) has rectangular circumferential extensions 120A and 120B at both ends thereof. The circumferentially extending portions 120 </ b> A and 120 </ b> B are arranged on the outer peripheral surface of the core body 110 in the circumferential direction at both ends in the longitudinal direction of the foamed elastic layer 120 by being wound around the core body 110. Accordingly, the both ends of the foamed elastic layer 120 shown in FIG. 5 are larger than the circumferential length (circumferential length) R1 of the core 110 of the foamed elastic layer 120 in the region 120C other than both ends of the foamed elastic layer 120 shown in FIG. The circumferential length (circumferential length) L1 of the core of the foamed elastic layer 120 at the portion becomes longer. Therefore, at the end of the foamed elastic layer 120, a large adhesion area is secured along the circumferential direction of the core body 110, and the force to peel the foamed elastic layer from the core body is dispersed, so that the foamed elastic layer 120 is peeled off. Will be suppressed.
In addition, since a large contact area with the member to be cleaned at the end of the foamed elastic layer 120 is ensured, the cleaning performance at the end is improved.

Further, if the circumferentially extending portions 120A and 120B of the foamed elastic layer 120 are compressed in the thickness direction, it is more difficult to peel off, and the contact area with the charging roll is ensured at both ends as well as the areas other than both ends. High cleaning performance is exhibited.
Moreover, if a notch is provided in the circumferentially extending portion, a high cleaning property is exhibited as the deformation amount of the foamed elastic layer is increased due to the formation of the edge portion.

  In the charging device, the process cartridge, and the image forming apparatus including the cleaning member 100 according to this embodiment, the foamed elastic layer 120 is peeled off from the core body 110 (particularly from the longitudinal end of the foamed elastic layer 120). (Peeling) is suppressed, and high cleaning performance is ensured even at the end portion, so that charging performance deterioration due to poor cleaning of the charging member and image defects (for example, density unevenness) due to the charging performance are suppressed.

  Hereinafter, each member will be described.

-Core-
First, the core body will be described.
Examples of the material used for the core body 110 include metals (for example, free-cutting steel or stainless steel), or resins (for example, polyacetal resin (POM)). In addition, it is desirable to select a material, a surface treatment method, etc. as needed.
In particular, when the core 110 is made of metal, it is desirable to perform plating. Further, in the case of a material such as a resin that does not have conductivity, it may be processed by a general process such as a plating process, and may be used as it is.

-Adhesive layer-
Next, the adhesive layer will be described.
The adhesive layer 130 is not particularly limited as long as the core body 110 and the foamed elastic layer 120 can be bonded to each other. For example, the adhesive layer 130 includes a double-sided tape or other adhesive.

-Foam elastic layer-
Next, the foamed elastic layer will be described.
The foamed elastic layer 120 is a spiral foamed elastic member 120 disposed in a spiral shape, and the circumferential length of the core 110 of the foamed elastic layer 120 at both ends in the longitudinal direction is other than the end. Circumferentially extending portions 120 </ b> A and 120 </ b> B are arranged on the outer peripheral surface of the core body 110 in the circumferential direction so as to be longer than the length of the foamed elastic layer 120 in the circumferential direction of the core body 110. Due to the presence of the circumferentially extending portions 120 </ b> A and 120 </ b> B at both ends, the foamed elastic layer 120 adheres to the outer peripheral surface of the core body 110 in the circumferential direction longer than the other regions at both ends.

  The length X1 in the circumferential direction of the core body 110 of the circumferentially extending portions 120A and 120B in the foamed elastic layer 120 is not particularly limited, but is preferably as follows from the viewpoint of peeling suppression and cleaning properties at the end. When the circumferential length of the foamed elastic layer 120 other than the end is R1, and the circumferential length of the core is Y, X1 is 10% or more and 90% or less with respect to the range 0 to Y-R1 that X1 can take. It is desirable to adhere. X1 represents the circumferential length on the core.

  On the other hand, the axial width X2 of the core body 110 in the circumferentially extending portions 120A and 120B of the foamed elastic layer 120 is not particularly limited. It is a portion within 2 mm (more preferably within 20 mm) from both ends in the direction toward the center.

The foam elastic layer 120 is made of a material having bubbles (so-called foam).
Examples of the material of the foamed elastic layer 120 include foamable resins such as polyurethane, polyethylene, polyamide, and polypropylene, or silicone rubber, fluorine rubber, urethane rubber, EPDM, NBR, CR, chlorinated polyisoprene, isoprene, Examples thereof include materials obtained by blending one kind or two or more kinds of rubber materials such as acrylonitrile-butadiene rubber, styrene-butadiene rubber, hydrogenated polybutadiene, and butyl rubber.
In addition, you may add adjuvants, such as a foaming aid, a foam stabilizer, a catalyst, a hardening | curing agent, a plasticizer, or a vulcanization accelerator, to these as needed.

In particular, the foamed elastic layer 120 is preferably a foamed polyurethane that is resistant to pulling from the viewpoint of preventing scratches on the surface of the member to be cleaned due to rubbing and preventing tearing and damage over a long period of time.
Examples of the polyurethane include polyol (for example, polyester polyol, polyether polyol, and acrylic polyol) and isocyanate (for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, and tolidine). Reaction products such as diisocyanate and 1,6-hexamethylene diisocyanate), and chain extenders (1,4-butanediol, trimethylolpropane) may be included.
In general, foaming of polyurethane is performed using a foaming agent such as water or an azo compound (for example, azodicarbonamide, azobisisobutyronitrile).
You may add auxiliary agents, such as a foaming aid, a foam stabilizer, and a catalyst, to foamed polyurethane as needed.

Of these foamed polyurethanes, ether-based foamed polyurethane is preferable. This is because ester-based foamed polyurethane tends to be susceptible to wet heat degradation. Ether-based polyurethanes mainly use silicone oil foam stabilizers, but image quality defects due to transfer of silicone oil to the member to be cleaned (eg, charging roll) during storage (especially long-term storage under high temperature and high humidity) May occur. Therefore, image quality defects of the foamed elastic layer 120 are suppressed by using a foam stabilizer other than silicone oil.
Here, specific examples of the foam stabilizer other than silicone oil include organic surfactants that do not contain Si (for example, anionic surfactants such as dodecylbenzenesulfonic acid and sodium lauryl sulfate). . Moreover, the manufacturing method which does not use the silicone type foam stabilizer described in Unexamined-Japanese-Patent No. 2005-301000 is also applicable.
Whether or not the ester-based foamed polyurethane uses a foam stabilizer other than silicone oil is determined by component analysis based on whether or not it contains “Si”.

  The thickness (thickness at the center in the width direction) of the foamed elastic layer 120 is, for example, 1.0 mm or more and 4.0 mm or less, desirably 1.2 mm or more and 3.0 mm or less, more desirably 1.8 mm or more. It is 2.6 mm or less.

The thickness of the foamed elastic layer 120 is measured as follows, for example.
Scanning in the longitudinal direction (axial direction) of the cleaning member at a traverse speed of 1 mm / s using a laser measuring machine (laser scanning micrometer manufactured by Mitutoyo Corporation, model: LSM6200) with the circumferential direction of the cleaning member fixed. The profile of the foamed elastic layer thickness (foamed elastic layer thickness) is measured. Then, the circumferential direction position is shifted and the same measurement is performed (the circumferential direction position is 120 ° interval, 3 locations). Based on this profile, the thickness of the foamed elastic layer 120 is calculated.

  The foamed elastic layer 120 is arranged in a spiral shape. Specifically, for example, the spiral angle θ is 10 ° to 65 ° (desirably 20 ° to 50 °), and the spiral width P1 is 3 mm to 25 mm. Or less (preferably 3 mm or more and 10 mm or less). Further, the spiral pitch P2 is preferably, for example, 3 mm or more and 25 mm or less (desirably 15 mm or more and 22 mm or less).

The foamed elastic layer 120 has a coverage ratio (spiral width P1 / of the foamed elastic layer 120 [spiral width P1 of the foamed elastic layer 120 + spiral pitch P2 of the foamed elastic layer 120: (P1 + P2)]) of 20% or more and 70% or less. It is often 25% or more and 55% or less.
When this coverage is larger than the above range, the time during which the foamed elastic layer 120 is in contact with the member to be cleaned becomes longer, and therefore, the deposit attached to the surface of the cleaning member tends to be recontaminated to the member to be cleaned. If the coverage is smaller than the above range, the thickness (wall thickness) of the foamed elastic layer 120 becomes difficult to stabilize, and the cleaning ability tends to decrease.

Note that the helical angle θ means an angle (acute angle) at which the longitudinal direction P (spiral direction) of the foamed elastic layer 120 and the axial direction Q (core axis direction) of the cleaning member intersect.
The spiral width P1 means a length along the axial direction Q (core axial direction) of the cleaning member 100 of the foamed elastic layer 120.
The spiral pitch P2 means the length between adjacent foamed elastic layers 120 along the axial direction Q (core axis direction) of the cleaning member 100 of the foamed elastic layer 120.
The foamed elastic layer 120 is a layer made of a material that can be restored to its original shape even when deformed by applying an external force of 100 Pa.

The foamed elastic layer 120 is a surface (hereinafter referred to as the foamed elastic layer 120) of the foamed elastic layer 120 on the side facing the outer peripheral surface of the core 110 at least in the circumferential extension 120A, 120B at one or both of the longitudinal ends. The surface on the side facing the outer peripheral surface of the core body 110 may be referred to as a “lower surface” or “adhesion surface.”) The region that contacts (adheres) the outer peripheral surface of the core body 110 via the adhesive layer 130 Is preferably 40% or more, more preferably 60% or more in terms of area ratio per unit area (hereinafter referred to as contact area ratio).
Note that the higher the area ratio, the easier it is to obtain an adhesive force equal to or greater than the rebound resilience generated at one or both of the longitudinal ends of the foamed elastic layer 120, and the foamed elastic layer 120 is peeled off from the core 110. This is suppressed (particularly, peeling from the end in the longitudinal direction of the foamed elastic layer 120).

  In the foamed elastic layer 120, the entire adhesive surface may be in the range of the contact area ratio, but from the viewpoint of cleaning properties, only the circumferential extension portions 120A and 120B at one or both of the longitudinal ends are the contact area ratio. It is good to set it as the range.

  Here, the “contact area ratio” refers to the total area of the lower surface of the foamed elastic layer 120 (projected area when projected in the layer thickness direction) through the adhesive layer 130 of the lower surface of the foamed elastic layer 120. It means the ratio of the area of the region in contact with the outer peripheral surface of the core body 110 (that is, in direct contact with the adhesive layer 130). In other words, the lower surface of the foamed elastic layer 120 has a concavo-convex shape, and the top portion (top surface) of the convex portion is in contact with the outer peripheral surface of the core body 110 via the adhesive layer 130 (that is, in direct contact with the adhesive layer 130). Therefore, the “contact area ratio” refers to the top of the convex portion (top) in contact with the outer peripheral surface of the core body 110 via the adhesive layer 130 with respect to the entire area of the lower surface of the foamed elastic layer 120. The ratio of the area of the surface.

The “contact area ratio” is a value obtained as follows.
A part of the foamed elastic layer 120 to be measured is peeled off from the cleaning member 100 by a cutter to obtain an elastic layer sample.
An elastic layer sample was placed on a horizontal ink base on which a liquid ink film (thickness: 100 μm) was formed so that the surface to be measured (the layer that is the lower surface of the foamed elastic layer 120) was in contact with the ink. Thereafter, pressing is performed from above the elastic layer sample with a force of 40 g / cm ² load, and a part of the measurement target surface (the structural skeleton portion of the foam) of the elastic layer sample is colored with ink.
Then, the measurement target surface of the elastic layer sample was photographed using a microscope (manufactured by Keyence Corporation, model: VHX-200), and an image analysis software (manufactured by Mitani Corporation, WinROOF) was used to capture the range of the photographed image 1 mm × 1 mm square. Using, binarization is performed between the colored portion and the non-colored portion, the ratio of the contact portion in the measurement target surface is measured, and this is defined as the contact area ratio.
The condition for binarization in the image analysis software is that image analysis processing is performed on a captured image that has been converted to black and white with 255 gradations based on the threshold value obtained by the “discriminant analysis method”. A threshold value or more is defined as a colored portion, and a value below the threshold is defined as a non-colored portion.

In order to set the “contact area ratio” within the above range, for example, the thickness of the foamed elastic layer 120 is formed on at least one of the longitudinal ends of the strip 120 (strip-shaped foamed elastic member) to be the foamed elastic layer 120. There is a method of performing compression processing (for example, thermal compression processing) in the direction.
Specifically, for example, a strip 120 (for example, a strip-shaped foamed elastic member having a foaming rate of 50/25 mm or more and 70/25 mm or less) before being wound around the core body 110 is prepared, and at least the end portion in the longitudinal direction. One or both of them is subjected to compression treatment by applying heat and pressure so that the compression ratio (thickness after compression / thickness before compression × 100) is 10% or more and 70% or less.
You may perform this compression process with respect to the foaming elastic member before cutting out in strip shape.
Thereby, the foam structure skeleton constituting the lower surface of the strip 120 (foam elastic layer 120) is likely to disappear (not completely disappear), and the contact area ratio is likely to increase.

In order to set the “contact area ratio” within the above range, for example, a circumferentially extending portion 120 </ b> A in at least one or both of the longitudinal ends of the strip 120 (strip-shaped foamed elastic member) to be the foamed elastic layer 120. , 120B, the surface to be bonded to the outer peripheral surface of the core body 110 may be formed of a non-foamed layer.
Specifically, for example, the strip 120 (foamed elastic layer 120) is formed of a laminate of a non-foamed layer and a foamed layer at least at one or both ends in the longitudinal direction.
This configuration is, for example, from the produced foamed elastic body (foam lump after molding and before cutting: for example, foamed urethane foam, etc.), the skin layer of the surface (non-foamed layer constituting the surface in contact with the mold) Is formed by cutting out the strip 120 (foamed elastic layer 120) so as to form the lower surface of the strip 120 (foamed elastic layer 120).
Thereby, the lower surface of the strip 120 (foaming elastic layer 120) is comprised with a non-foaming layer, and it becomes easy to increase a contact area rate.

  Here, the foamed elastic layer 120 is not limited to an embodiment composed of one strip 120, and is wound around the core body 110 in a spiral manner with two or more strips 120 (strip-shaped foamed elastic members) in parallel. You may be comprised by what was arrange | positioned.

  In addition, the shape of the circumferentially extending portions 120A and 120B of the strip 120 is not limited to a rectangular shape, and may be other shapes. For example, the strip 122 may have triangular circumferential extensions 122A and 122B as shown in FIG. 6, or may have semicircular or semi-elliptical circumferential extensions 124A and 124B as shown in FIG. A strip 124 may be used.

  Moreover, the notch part or level | step difference part may be provided in the outer peripheral surface of the boundary part of the circumferential direction extension part 120A, 120B of the foaming elastic layer 120. FIG. For example, as shown in FIG. 8, if the cut portion 121 is provided along the boundary between the circumferentially extending portions 120A and 120B in the foamed elastic layer 120, the cleaning property at the end portion can be further improved. The notch 121 is not limited to the boundary between the circumferential extensions 120A and 120B, and may be provided in the region of the circumferential extensions 120A and 120B. Further, the direction of the boundary of the notch or the step may be any angle as long as it is not 90 ° with respect to the longitudinal direction of the core.

  Further, for example, a cut portion 121 is provided in the boundary portion or region between the circumferentially extending portions 120A and 120B of the foamed elastic layer 120, and the thickness is compressed by a thickness direction compression process such as a heating press only on the tip side of the cut portion 121. You may provide a level | step-difference part by making thin.

(Manufacturing method of cleaning member)
Next, although the manufacturing method of the cleaning member 100 which concerns on this embodiment is demonstrated, it is not limited to this method.
FIG. 9 is a process diagram illustrating an example of a method for manufacturing the cleaning member 100 according to the present embodiment.

  First, as shown in FIG. 9A, a sheet-like foamed elastic member (foamed polyurethane sheet or the like) that has been sliced so as to have a desired thickness is prepared. Then, after applying the double-sided tape 130 as an adhesive layer, the member is punched out with a punching die to obtain a strip 120 having a desired width and length (a strip-shaped foamed elastic member with a double-sided tape). On the other hand, the core body 110 is also prepared.

Here, in order to make the “contact area ratio” within the above range, the sheet-like foamed elastic member may be subjected to a compression treatment, or the circumferential extension of the obtained strip-like foamed elastic member 120 may be applied. Compression processing may be performed. Note that the compression treatment may be performed before or after the double-sided tape as the adhesive layer 130 is pasted.
In addition, in order to make the “contact area ratio” within the above range, when a sheet-like foamed elastic member is obtained by slicing, the skin layer on the surface of the foamed elastic body before slicing (the surface in contact with the mold) The sheet-like foamed elastic member may be obtained by performing slicing so that the non-foamed layer to be configured constitutes the lower surface of the strip 120 (foamed elastic layer 120).

  Next, as shown in FIG. 9B, the strip 120 is placed with the surface with the double-sided tape 130 facing upward, and in this state, one end of the release paper of the double-sided tape 130 is peeled off, and the release paper is peeled off. One end of the core 110 is placed on the double-sided tape of the circumferentially extending portion of the strip 120.

  Next, as shown in FIG. 9C, the core body 110 is rotated at a target speed while peeling the release paper of the double-sided tape, and the strip 120 is spirally wound around the outer peripheral surface of the core body 110. As a result, the cleaning member 100 having the elastic layer 120 spirally disposed on the outer peripheral surface of the core body 110 is obtained.

  Here, when the strip 120 to be the elastic layer 120 is wound around the core body 110, the strip 120 is positioned so that the longitudinal direction of the strip 120 becomes a target angle (spiral angle) with respect to the axial direction of the core body 110. Can be combined. Further, the outer diameter of the core body 110 is preferably about φ3 mm to φ6 mm, for example.

  The tension applied when the strip 120 is wound around the core 110 may be such that there is no gap between the core 110 and the double-sided tape of the strip 120, and it is preferable that the tension is not excessively applied. This is because if the tension is applied too much, the tensile permanent elongation increases, and the elastic force of the foamed elastic layer 120 necessary for cleaning tends to decrease. Specifically, for example, the tension may be set to an elongation of 0% to 5% or less with respect to the length of the original strip 120.

(Image forming devices, etc.)
Hereinafter, an image forming apparatus according to the present embodiment will be described with reference to the drawings.
FIG. 10 is a schematic configuration diagram illustrating an image forming apparatus according to the present embodiment.

  The image forming apparatus 10 according to the present embodiment is, for example, a tandem color image forming apparatus as shown in FIG. In the image forming apparatus 10 according to the present embodiment, a photosensitive member (image holding member) 12, a charging member 14, a developing device, and the like are provided with yellow (18Y), magenta (18M), cyan (18C), and black ( 18K) is provided as a process cartridge (see FIG. 11) for each color. This process cartridge is configured to be attached to and detached from the image forming apparatus 10.

  As the photoconductor 12, for example, a conductive cylinder having a diameter of 25 mm, which is coated with a photoconductor layer made of an organic photosensitive material or the like, is used. The photoconductor 12 is driven to rotate at a process speed of 150 mm / sec by a motor (not shown). The

  The surface of the photoconductor 12 is charged by a charging member 14 disposed on the surface of the photoconductor 12 and then imaged by a laser beam LB emitted from the exposure device 16 downstream of the charging member 14 in the rotation direction of the photoconductor 12. Exposure is performed, and an electrostatic latent image according to image information is formed.

  The electrostatic latent image formed on the photoreceptor 12 is developed by developing devices 19Y, 19M, 19C, and 19K for each color of yellow (Y), magenta (M), cyan (C), and black (K). Toner image.

  For example, when a color image is formed, the charging, exposure, and development processes are performed on the surface of the photoreceptor 12 of each color in yellow (Y), magenta (M), cyan (C), and black (K). The toner image corresponding to each color of yellow (Y), magenta (M), cyan (C), and black (K) is formed on the surface of the photoreceptor 12 of each color.

The black (K), cyan (C), magenta (M), and yellow (Y) toner images sequentially formed on the photoconductor 12 are tensioned by the support rolls 40 and 42 from the inner peripheral surface. The image is transferred to the recording sheet 24 conveyed on the sheet conveying belt 20 to the outer periphery of the photosensitive element 12 at a position where the photosensitive element 12 and the transfer device 22 are in contact via the supported sheet conveying belt 20. Further, the recording paper 24 onto which the toner image has been transferred from the photoreceptor 12 is conveyed to the fixing device 64, and is heated and pressurized by the fixing device 64 to fix the toner image on the recording paper 24. Thereafter, in the case of single-sided printing, the recording paper 24 on which the toner image is fixed is discharged as it is onto a discharge unit 68 provided on the upper part of the image forming apparatus 10 by a discharge roll 66.
The recording paper 24 is taken out from the paper storage container 28 by the take-out roller 30 and conveyed to the paper conveyance belt 20 by the conveyance rollers 32 and 34.

  On the other hand, in the case of double-sided printing, the recording paper 24 on which the toner image is fixed on the first surface (front surface) by the fixing device 64 is not directly discharged onto the discharge portion 68 by the discharge roll 66 but by the discharge roll 66. With the rear end portion of the recording paper 24 being held, the discharge roller 66 is reversed, the conveyance path of the recording paper 24 is switched to the double-sided paper conveyance path 70, and the double-sided paper conveyance path 70 is disposed. Then, the recording paper 24 is conveyed again onto the paper conveying belt 20 with the conveying roller 72 reversed, and the toner image is transferred from the photoreceptor 12 onto the second surface (back surface) of the recording paper 24. To do. Then, the toner image on the second surface (back surface) of the recording paper 24 is fixed by the fixing device 64, and the recording medium 24 (transfer object) is discharged onto the discharge portion 68.

  Note that the surface of the photoconductor 12 after the toner image transfer process is completed is the surface of the photoconductor 12 every time the photoconductor 12 makes one rotation, and is closer to the surface of the photoconductor 12 than the portion where the transfer device 22 contacts. Residual toner, paper dust, and the like are removed by a cleaning blade 80 disposed on the downstream side in the rotation direction so as to prepare for the next image forming process.

Here, as shown in FIG. 12, the charging member 14 is, for example, a roll in which a foamed elastic layer 14B is formed around the conductive core 14A, and the core 14A is rotatably supported. The cleaning member 100 of the charging member 14 is in contact with the charging member 14 on the side opposite to the photosensitive member 12 to constitute a charging device (unit). As the cleaning member 100, the cleaning member 100 according to the present embodiment is used.
Here, the cleaning member 100 is always in contact with the charging member 14 and is used while being driven by the charging member 14. However, the cleaning member 100 may be always in contact with the charging member 14 or may be used by being driven. It may be used in contact with and driven only during cleaning. Further, the cleaning member 100 may be brought into contact only when the charging member 14 is cleaned, and a peripheral speed difference may be given to the charging member 14 by separate driving. However, the method in which the cleaning member 100 is always brought into contact with the charging member 14 to create a difference in peripheral speed is not desirable because dirt on the charging member 14 is easily accumulated in the cleaning member 100 and easily reattached to the charging roll.

  The charging member 14 applies a load F to both ends of the core 14A and presses it against the photoconductor 12, and is elastically deformed along the peripheral surface of the foamed elastic layer 14B to form a nip portion. Further, the cleaning member 100 applies a load F ′ to both ends of the core body 110 and presses it against the charging member 14, and the foamed elastic layer 120 is elastically deformed along the peripheral surface of the charging member 14 to form a nip portion. An axial nip portion between the charging member 14 and the photosensitive member 12 is formed by suppressing the bending of the charging member 14.

  The photoconductor 12 is rotationally driven in the direction of arrow X by a motor (not shown), and the charging member 14 is driven to rotate in the direction of arrow Y by the rotation of the photoconductor 12. Further, the cleaning member 100 is driven to rotate in the direction of the arrow Z by the rotation of the charging member 14.

-Configuration of charging member-
Hereinafter, the charging member will be described, but it is not limited to the following configuration.

  Although it does not specifically limit as a structure of a charging member, For example, the structure which has a resin layer instead of a core, a foaming elastic layer, or a foaming elastic layer is mentioned. The foamed elastic layer may be composed of a single layer, or may be a laminated structure composed of a plurality of different layers having several functions. Furthermore, a surface treatment may be performed on the foamed elastic layer.

  It is desirable to use free-cutting steel, stainless steel or the like as the material of the core, and to select the material and the surface treatment method in a timely manner according to applications such as slidability. Further, it is desirable to perform a plating process. In the case of a material that does not have conductivity, it may be processed by a general process such as a plating process to perform a conductive process, or may be used as it is.

  The foamed elastic layer is a conductive foamed elastic layer. For example, the conductive foamed elastic layer is an elastic material such as rubber having elasticity, or a conductive material such as carbon black or an ionic conductive material that adjusts the resistance of the conductive foamed elastic layer. Materials that can be usually added to rubber, such as materials, softeners, plasticizers, curing agents, vulcanizing agents, vulcanization accelerators, anti-aging agents, fillers such as silica or calcium carbonate, may be added as necessary. . It is formed by coating a peripheral surface of a conductive core with a mixture in which materials usually added to rubber are added. As the conductive agent for the purpose of adjusting the resistance value, a material in which a material that conducts electricity using at least one of electrons and ions such as carbon black and an ionic conductive agent mixed in the matrix material as a charge carrier is used. The elastic material may be a foam.

  The elastic material constituting the conductive foamed elastic layer is formed, for example, by dispersing a conductive agent in a rubber material. Preferred examples of the rubber material include silicone rubber, ethylene propylene rubber, epichlorohydrin-ethylene oxide copolymer rubber, epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer rubber, acrylonitrile-butadiene copolymer rubber, and blended rubbers thereof. These rubber materials may be foamed or non-foamed.

  As the conductive agent, an electronic conductive agent or an ionic conductive agent is used. Examples of the electronic conductive agent include carbon black such as ketjen black and acetylene black; pyrolytic carbon, graphite; various conductive metals or alloys such as aluminum, copper, nickel, stainless steel; tin oxide, indium oxide, titanium oxide And fine powders such as various conductive metal oxides such as tin oxide-antimony oxide solid solution, tin oxide-indium oxide solid solution, and the like. Examples of ionic conductive agents include perchlorates and chlorates of oniums such as tetraethylammonium and lauryltrimethylammonium; alkali metals such as lithium and magnesium, perchlorates of alkaline earth metals, chlorine Acid salts and the like.

  These conductive agents may be used alone or in combination of two or more. The amount of addition is not particularly limited, but in the case of an electronic conductive agent, it is desirable that the amount be in the range of 1 part by weight to 60 parts by weight with respect to 100 parts by weight of the rubber material. In such a case, it is desirable that the amount be in the range of 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the rubber material.

A surface layer may be formed on the surface of the charging member. As the material for the surface layer, any of resin, rubber and the like may be used, and there is no particular limitation. For example, polyvinylidene fluoride, tetrafluoroethylene copolymer, polyester, polyimide, and copolymer nylon are preferable.
The copolymer nylon includes one or more of 610 nylon, 11 nylon, and 12 nylon as polymerized units, and other polymer units contained in the copolymer include 6 nylon. 66 nylon and the like. Here, it is desirable that the ratio of polymer units composed of 610 nylon, 11 nylon, and 12 nylon to be contained in the copolymer is 10% or more in total by weight ratio.

  The polymer materials may be used alone or in combination of two or more. The number average molecular weight of the polymer material is preferably in the range of 1,000 to 100,000, and more preferably in the range of 10,000 to 50,000.

  Further, the surface layer may contain a conductive material to adjust the resistance value. The conductive material preferably has a particle size of 3 μm or less.

  In addition, as a conductive agent for adjusting the resistance value, carbon black or conductive metal oxide particles blended in the matrix material, or a material that conducts electricity using at least one of electrons and ions such as an ionic conductive agent as a charge carrier A material in which is dispersed may be used.

Specifically, carbon black as a conductive agent includes “Special Black 350”, “Special Black 100”, “Special Black 250”, “Special Black 5”, “Special Black 4” manufactured by Degussa, "Special Black 4A", "Special Black 550", "Special Black 6", "Color Black FW200", "Color Black FW2", "Color Black FW2V", "MONARCH1000" manufactured by Cabot, Cabot “MONARCH1300” manufactured by the company, “MONARCH1400” manufactured by Cabot, “MOGUL-L”, “REGAL400R”, and the like.
Carbon black desirably has a pH of 4.0 or less.

  The conductive metal oxide particles that are conductive particles for adjusting the resistance value are particles having conductivity such as tin oxide, tin oxide doped with antimony, zinc oxide, anatase titanium oxide, ITO, etc. Any conductive agent using electrons as charge carriers can be used without any particular limitation. These may be used alone or in combination of two or more. Any particle size may be used, but tin oxide, antimony-doped tin oxide, and anatase-type titanium oxide are desirable, and tin oxide and antimony-doped tin oxide are desirable.

  Furthermore, a fluorine-based or silicone-based resin is preferably used for the surface layer. In particular, it is desirable to be composed of a fluorine-modified acrylate polymer. Moreover, you may add particle | grains in a surface layer. In addition, insulating particles such as alumina and silica are added to provide a concave portion on the surface of the charging member, reducing the load at the time of rubbing against the photosensitive member, and improving the wear resistance between the charging member and the photosensitive member. It may be improved.

  The outer diameter of the charging member is desirably 8 mm or greater and 16 mm or less. Moreover, as a measuring method of an outer diameter, it measures using a commercially available caliper or a laser type outer diameter measuring apparatus.

  The micro hardness of the charging member is preferably 45 ° or more and 60 ° or less. In order to reduce the hardness, it is conceivable to increase the amount of plasticizer added, or to use a low hardness material such as silicone rubber.

  Further, the micro hardness of the charging member can be measured with an MD-1 type hardness meter manufactured by Kobunshi Keiki Co., Ltd.

  In the image forming apparatus according to the present embodiment, the process cartridge including the photosensitive member (image holding member), the charging device (unit of the charging member and the cleaning member), the developing device, and the cleaning blade (cleaning device) has been described. However, the present invention is not limited to this, and includes a charging device (unit of charging member and cleaning member), and, if necessary, a photosensitive member (image holding member), an exposure device, a transfer device, a developing device, and a cleaning blade (cleaning). It may be a process cartridge provided with one selected from the apparatus. Note that these devices and members may be arranged directly in the image forming apparatus without being made into a cartridge.

  Further, in the image forming apparatus according to the present embodiment, the configuration in which the charging device is configured by the unit of the charging member and the cleaning member has been described, that is, the configuration in which the charging member is employed as the member to be cleaned has been described. The member to be cleaned is not limited to this, and includes a photosensitive member (image holding member), a transfer device (transfer member; transfer roll), and an intermediate transfer member (intermediate transfer belt). The unit of the member to be cleaned and the cleaning member disposed in contact with the member may be directly disposed in the image forming apparatus, or may be disposed in the image forming apparatus as a process cartridge as described above. May be.

  Further, the image forming apparatus according to the present embodiment is not limited to the above configuration, and a known image forming apparatus such as an intermediate transfer type image forming apparatus may be employed.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Example 1]
(Preparation of cleaning roll 1)
A sheet of urethane foam (EP-70; manufactured by Inoac Corporation) with a thickness of 2.5 mm is pasted with a double-sided tape with a thickness of 0.15 mm, a thickness of 2.65 mm, a width (W1) of 4.0 mm, and a length of 245 mm. A rectangular shape was formed in the shape of a strip, and the circumferentially extending portion was a region (X2) having both end portions of 2 mm and a width (X1) of 2.4 mm.

  Next, this strip-shaped urethane foam sheet is wound around a SUS core (outer diameter φ4 mm, total length 230 mm) at a winding angle (spiral angle θ) of 25 °, and the total length of the strip is greater than 0% and less than 5%. A spiral elastic layer was formed by applying a tension so as to extend to some extent. Finally, a compression treatment was performed so that the end portion circumferential length of 2.4 mm serving as the circumferential extension portion was 8% in thickness. The circumferential length (R1) of the cleaning effective portion (region other than the end portion of the foamed elastic layer) of the cleaning roll 1 thus obtained is 4.4 mm, and the peripheral length of the cleaning effective portion at the end portion is 4. It was 4 mm.

(Preparation of charging roll)
-Formation of foamed elastic layer-
The following mixture is kneaded with an open roll, coated on the surface of a conductive support made of SUS416 with a diameter of 6 mm in a cylindrical shape with a thickness of 1.5 mm, and placed in a cylindrical mold with an inner diameter of 18.0 mm. And vulcanized at 170 ° C. for 30 minutes. After taking out from the mold, it was polished to obtain a cylindrical conductive foamed elastic layer A.

-Mixture for forming foamed elastic layer-
・ Rubber material ... 100 parts by mass (Epichlorohydrin-ethylene oxide-allyl glycidyl ether copolymer rubber) Gechron 3106: manufactured by Nippon Zeon Co., Ltd.)
-Conductive agent (Carbon Black Asahi Thermal: Asahi Carbon Co., Ltd.) ... 25 parts by mass- Conductive agent (Ketjen Black EC: Lion Corp.) ... 8 parts by mass- Ionic conductive agent (lithium perchlorate) ) ··· 1 part by mass · Vulcanizing agent (sulfur) 200 mesh: manufactured by Tsurumi Chemical Co., Ltd. · · · 1 part by mass · Vulcanization accelerator (Noxeller DM: Ouchi Shinsei Chemical Co., Ltd.)・ 2.0 parts by mass ・ Vulcanization accelerator (Noxeller TT: Ouchi Shinsei Chemical Co., Ltd.) ・ ・ ・ ・ 0.5 parts by mass

-Formation of surface layer-
Dispersion A obtained by dispersing the following mixture in a bead mill is diluted with methanol, dip-coated on the surface of the conductive foamed elastic layer A, and then heated and dried at 140 ° C. for 15 minutes to obtain a surface having a thickness of 4 μm. A layer was formed to obtain a conductive roll. This was used as a charging roll.

-Mixture for surface layer formation-
-Polymer material: 100 parts by mass (copolymer nylon) Alamine CM8000: manufactured by Toray Industries, Inc.-Conductive agent: 30 parts by mass (antimony-doped tin oxide) SN-100P: manufactured by Ishihara Sangyo Co., Ltd.- Solvent (methanol) ... 500 parts by mass / solvent (butanol) ... 240 parts by mass

[Example 2]
(Preparation of cleaning roll 2)
Example 1 except that a foamed urethane sheet having a triangular shape with a maximum width (X1) of 2.4 mm is used as the circumferentially extending portion only in the region (X2) of both ends 2 mm of the strip-shaped foamed urethane sheet. Similarly, the cleaning roll 2 was produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 3]
(Preparation of cleaning roll 3)
After the urethane foam sheet similar to that in Example 1 was spirally wound around the core as in Example 1, the cleaning roll 3 was produced in the same manner as in Example 1 except that the end portion was not compressed. did.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 4]
(Preparation of cleaning roll 4)
After the foamed urethane sheet similar to that in Example 2 was spirally wound around the core in the same manner as in Example 2, the cleaning roll 4 was produced in the same manner as in Example 2 except that the end portion was not compressed. did.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 5]
(Preparation of cleaning roll 5)
Example 1 except that the foamed urethane sheet similar to Example 1 was spirally wound around the core in the same manner as in Example 1 and then subjected to compression at the end so that the total thickness was 48%. Similarly, the cleaning roll 5 was produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 6]
(Preparation of cleaning roll 6)
A foamed urethane sheet similar to that in Example 1 was spirally wound around the core in the same manner as in Example 1 and then subjected to compression treatment at the end so that the total thickness was 72%. Similarly, the cleaning roll 6 was produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 7]
(Preparation of cleaning roll 7)
A cleaning roll 7 was produced in the same manner as in Example 1 except that a semicircular foamed urethane sheet having a diameter of 2 mm was used only in the region of 2 mm on both ends of the strip-shaped foamed urethane sheet.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 8]
(Preparation of cleaning roll 8)
The cleaning roll 8 is formed in the same manner as in Example 1 except that a foamed urethane sheet having a cut portion having a depth of 2 mm is used on the outer peripheral surface of the boundary region of the circumferentially extending portion at both ends of the strip-shaped foamed urethane sheet. Produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Example 9]
(Preparation of cleaning roll 9)
A cleaning roll 9 was produced in the same manner as in Example 3 except that only the double-faced tape-attached surface side of the strip-shaped foamed urethane sheet was a skin layer (non-foamed layer).
(Preparation of charging roll)
The same thing as Example 1 was used.

[Comparative Example 1]
(Preparation of cleaning roll 10)
A cleaning roll 10 was produced in the same manner as in Example 1 except that the circumferential extension was eliminated.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Comparative Example 2]
(Preparation of cleaning roll 11)
A cleaning roll 11 was produced in the same manner as in Comparative Example 1 except that the foamed urethane sheet similar to Comparative Example 1 was spirally wound around the core in the same manner as in Comparative Example 1 and then the end portion was not compressed. did.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Comparative Example 3]
(Preparation of cleaning roll 12)
Comparative Example 1 is the same as Comparative Example 1 except that the foamed urethane sheet similar to Comparative Example 1 is spirally wound around the core in the same manner as Comparative Example 1 and then subjected to compression treatment at the end so that the total thickness becomes 48%. Similarly, a cleaning roll 12 was produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Comparative Example 4]
(Preparation of cleaning roll 13)
Comparative Example 1 is the same as Comparative Example 1 except that the foamed urethane sheet similar to Comparative Example 1 is spirally wound around the core in the same manner as Comparative Example 1 and then subjected to compression treatment at the end so that the total thickness becomes 72%. Similarly, the cleaning roll 13 was produced.
(Preparation of charging roll)
The same thing as Example 1 was used.

[Evaluation]
Using the cleaning roll and the charging roll produced in each example, the cleaning property and peeling of the foamed elastic layer were evaluated.
The “contact area ratio” of the lower surface (adhesion surface) of the circumferential extension of the foamed elastic layer of the cleaning roll produced in each example was measured by the method described above.

(Cleaning evaluation test)
A cleaning property evaluation test was performed using the cleaning rolls prepared in each example.
The amount of biting was adjusted by adjusting the distance between the charging roll and the cleaning roll so that the distance between the charging roll and the cleaning roll was 8.1 mm. Specifically, the cleaning roll and the charging roll were mounted in a process cartridge of a color printer DocuPrint C2110 (manufactured by Fuji Xerox Co., Ltd.), and the following cleaning property evaluation test was performed. The voltage applied to the charging roll, the rotation speed of the charging roll, and the developer used were the same in each example.

  The cleaning property evaluation test was performed by printing 150,000 image quality patterns with an average image density of 5% on A4 paper and then outputting one halftone image with a density of 30%. The obtained halftone image having a density of 30% is visually classified as A where no density unevenness in image quality occurs and B where density unevenness in image quality is unacceptable. It was done by evaluation. In addition, the edge part (area | region of 20 mm of both ends of a short side) and area | regions other than an edge part of the output A4 paper were evaluated, respectively.

(Peeling evaluation)
The cleaning roll and charging roll produced in each of the above examples were mounted in a drum cartridge of a color printer DocuPrint C2110 (manufactured by Fuji Xerox Co., Ltd.) and left for 30 days in an environment of 50 ° C./75%, and then based on the following criteria: The peeling evaluation of the cleaning part (foamed elastic layer) of the cleaning member was performed.
In addition, the state where peeling of the cleaning part of the cleaning member determined here was evaluated based on the following criteria for the length of one end or both ends in the longitudinal direction of the foamed elastic layer away from the metal core.

-Peeling evaluation: Judgment criteria-
A: No peeling occurred B: The urethane length where peeling occurred was less than 1 mm C: The urethane length where peeling occurred 1 mm or more

  The evaluation results are shown in Table 1.

  From the above results, it can be seen that this example has better evaluation of peeling and cleaning as compared with the comparative example.

DESCRIPTION OF SYMBOLS 10 Image forming apparatus, 12 Photoconductor, 14A Core body, 14 Charging member, 14B Foam elastic layer, 16 Exposure apparatus, 19Y, 19M, 19C, 19K Developing apparatus, 20 Paper conveyance belt, 22 Transfer apparatus, 24 Recording medium, 28 Paper storage container, 30 take-out roller, 32, 34 transport roll, 40, 42 support roll, 64 fixing device, 66 discharge roll, 6 discharge section, 70 paper transport path, 72 transport roll, 80 cleaning blade, 100 cleaning member, 110 Core body, 120A, 120B circumferential extension, 120 foamed elastic layer (foamed elastic member, strip), 121 notch, 130 adhesive layer (double-sided tape), P longitudinal direction, Q axis direction, P1 spiral width, P2 spiral pitch , Θ Spiral angle

Claims (11)

The core,
A foamed elastic layer in which a strip-shaped foamed elastic member is spirally wound from one end to the other end of the core body on the outer peripheral surface of the core body, and the longitudinal end of the foamed elastic layer circumferential direction of the so that the length is longer than the circumferential length of the core body of the foamed elastic layer in the region other than the end foamed elastic of one or the core of the foamed elastic layer in both body parts A foamed elastic layer having a circumferential extension extending in the circumferential direction of the core from the longitudinal end of the layer;
An adhesive layer that bonds the core and the foamed elastic layer;
Cleaning member provided with. In the foamed elastic layer, the circumferential length of the circumferential extension at one or both of the longitudinal ends of the foamed elastic layer is X1, the circumferential length of the core is Y, and the region other than the ends The cleaning according to claim 1, wherein the foamed elastic layer satisfies a relationship of (Y−R1) × 10% ≦ X1 ≦ (Y−R1) × 90%, where R1 is a circumferential length of the core body. Element. Of the surface on the side facing the outer peripheral surface of the core body in the circumferentially extending portion of the foamed elastic layer, the area of the region that contacts the outer peripheral surface of the core body via the adhesive layer is the area per unit area The cleaning member according to claim 1 , wherein the cleaning member has a rate of 40% or more. The cleaning member according to any one of claims 1 to 3 , wherein a cut portion or a step portion is provided on an outer peripheral surface of a boundary portion of the circumferential extension portion of the foamed elastic layer. The surface which adhere | attaches on the outer peripheral surface of the said core body through the said adhesive layer in the said circumferential direction extension part of the said foaming elastic layer is any one of Claims 1-4 comprised by the non-foaming layer. The cleaning member as described in. A charging member for charging the object to be charged;
The cleaning member according to any one of claims 1 to 5 , wherein the cleaning member is disposed in contact with the surface of the charging member and cleans the surface of the charging member.
A charging device comprising: At least the charging device according to claim 6 ,
A process cartridge that is detachable from the image forming apparatus. An image carrier,
A charging unit comprising the charging device according to claim 6 , and charging the surface of the image carrier.
Latent image forming means for forming a latent image on the surface of the charged image carrier;
Developing means for developing the latent image formed on the image carrier with a developer containing toner into a toner image;
Transfer means for transferring the toner image to a transfer object;
An image forming apparatus comprising: A member to be cleaned;
The cleaning member according to any one of claims 1 to 5 , wherein the cleaning member is disposed in contact with the surface of the member to be cleaned, and cleans the surface of the member to be cleaned.
A unit for an image forming apparatus. At least a unit for an image forming apparatus according to claim 9 ,
A process cartridge that is detachable from the image forming apparatus. An image forming apparatus comprising the unit for an image forming apparatus according to claim 9 .

Images