JP2021117384A - Cleaning blade, process cartridge, and image forming apparatus - Google Patents

Abstract

To provide a cleaning blade that can prevent poor cleaning, generation of abnormal noise, and chipping in a contact part, and fastening of an attachment, and reduces the likelihood that an aggregate derived from the attachment remains on a member to be cleaned after cleaning of the member to be cleaned.SOLUTION: A cleaning blade 62 has an elastic member 624 that is in contact with a surface of a member to be cleaned and removes an attachment attached to the surface of the member to be cleaned. The elastic member has a tip ridge part 62c. The elastic member contains domains having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less and derived from a polysiloxane structure in an area from a surface including the tip ridge part to a depth of 100 μm. The Martens hardness HM (load: 1000 μN) of the elastic member at a position 20 μm from the tip ridge part is 1.5 N/mm2 or more and 5.0 N/mm2 or less.SELECTED DRAWING: Figure 2

Description

The present invention relates to a cleaning blade, a process cartridge and an image forming apparatus.

Conventionally, in an electrophotographic image forming apparatus, an image carrier as a member to be cleaned (hereinafter, may be referred to as a "photoreceptor", an "electrophotographic photosensitive member", or an "image carrier") is a transfer paper or a transfer paper. It is known that unnecessary deposits such as transfer residual toner adhering to the surface after the toner image is transferred to the intermediate transfer body are removed by a cleaning means.

As a cleaning member of the cleaning means, a strip-shaped cleaning blade is generally well known because it can be easily configured and has excellent cleaning performance. In this method, the base end of the cleaning blade is supported by a support member, the contact portion (tip ridge line portion) is pressed against the peripheral surface of the image carrier, and the toner remaining on the image carrier is blocked and scraped off. ..

However, with conventional cleaning blades, when the coefficient of friction with the image carrier becomes high, the tip of the cleaning blade is turned over, causing abnormal noise and toner slipping, resulting in poor cleaning. Therefore, in order to reduce the coefficient of friction, a cleaning blade containing fluorine or a silicone system has been proposed (see, for example, Patent Document 1).

The present invention can suppress poor cleaning, generation of abnormal noise, defects at the contact portion, and adhesion of deposits, and further, after cleaning the member to be cleaned, agglomerates derived from the deposits remain on the member to be cleaned. An object of the present invention is to provide a cleaning blade that is difficult to handle.

The cleaning blade of the present invention, which is a means for solving the above problems, is
A cleaning blade having an elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned.
The elastic member has a tip ridgeline portion and has a tip ridgeline portion.
The elastic member contains a domain derived from a polysiloxane structure having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less in a region from the surface including the tip ridge line portion to a depth of 100 μm.
The tip from ridge portion of the elastic member at the position of 20μm Martens hardness HM (load: 1000μN) is 1.5 N / mm ² or more 5.0 N / mm ² or less,
It is characterized by that.

According to the present invention, it is possible to suppress poor cleaning, generation of abnormal noise, defects at the contact portion, and adhesion of deposits, and further, after cleaning the member to be cleaned, agglomerates derived from the deposits on the member to be cleaned. It is possible to provide a cleaning blade in which is less likely to remain.

FIG. 5 is an enlarged cross-sectional view showing an example of a state in which an example of a cleaning blade according to the present invention is in contact with the surface of an image carrier. It is a perspective view which shows an example of the cleaning blade which concerns on this invention. It is a figure for demonstrating the region from the surface including the tip ridge line part to the depth of 100 μm (the 1). It is a figure for demonstrating the region from the surface including the tip ridge line part to the depth of 100 μm (the 2). It is a figure for demonstrating the region from the surface including the tip ridge line part to the depth of 100 μm (the 3). It is a figure for demonstrating the region from the surface including the tip ridge line part to the depth of 100 μm (the 4). It is a schematic block diagram which shows an example of the image forming apparatus which concerns on this invention. It is a schematic block diagram which shows an example of the image formation unit provided in the image forming apparatus which concerns on this invention.

Hereinafter, the cleaning blade, the process cartridge, and the image forming apparatus according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments shown below, and can be modified within the range conceivable by those skilled in the art, such as other embodiments, additions, modifications, and deletions.

(Cleaning blade)
The cleaning blade of the present invention has an elastic member and, if necessary, other members such as a support.

The present inventors have obtained the following findings regarding cleaning blades.
In the cleaning blade, if the silicone oil is compatible with the elastic member (for example, polyurethane), there are the following problems.
・ The coefficient of friction does not decrease and the tip is turned over.
・ Durability will be reduced if silicone oil seeps out even if it is incompatible.
-If the dispersion diameter of silicone oil is large, the toner tends to stick to the blade, and the toner slips through it.
Further, especially in a system in which a lubricant is not applied to the photoconductor, the friction coefficient tends to be higher and the blade is likely to be turned over, or if the hardness of the tip of the blade is low, aggregates derived from the toner external agent are likely to form on the photoconductor. It will accumulate and image abnormalities will occur. Therefore, a cleaning blade having a high hardness has been proposed. However, if the hardness is made too high, the edge of the blade may be chipped, and there is a problem that the toner slips through the chip.

Therefore, the present inventors have conducted diligent studies. As a result, by combining the following (1) and (2), it is possible to suppress poor cleaning, generation of abnormal noise, defects at the contact portion, and adhesion of deposits, and further, after cleaning the member to be cleaned, it is covered. A cleaning blade was obtained in which agglomerates derived from deposits did not easily remain on the cleaning member.
(1) The elastic member contains a domain derived from a polysiloxane structural compound having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less in a region from the surface including the tip ridge to a depth of 100 μm.
(2) from said front edge portion of the elastic member at the position of 20μm Martens hardness HM (load: 1000MyuN) is 1.5 N / mm ² or more 5.0 N / mm ² or less.

Regarding (1) above, if the average dispersion diameter is less than 0.1 μm, the tip of the blade will be turned over. If the average dispersion diameter exceeds 5.0 μm, deposits will adhere to the blade. If the deposit is toner, a streak image will appear.
Regarding the above (2), if the Martens hardness HM is less ^{than 1.5 N / mm 2} , the component derived from the deposit cannot be cleaned, and the component adheres to the member to be cleaned. For example, when the deposit is toner and the member to be cleaned is a photoconductor, the component derived from the toner (for example, an external additive) cannot be cleaned, and the component adheres to the photoconductor, resulting in a white-out image or a whiteout image. White streak image occurs. If the Martens hardness HM ^{exceeds 5.0 N / mm 2} , the edge portion of the blade is likely to be chipped. For example, when the member to be cleaned is a photoconductor, if the edge portion of the blade is chipped, a streak image is generated. The streak image here is an abnormality different from the white streak image, and is a vertical streak image (black streak in the case of a black-and-white image) caused by poor cleaning.

An embodiment of the cleaning blade according to the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is an explanatory view of a state in which the cleaning blade 62 is in contact with the surface of the photoconductor 3, and FIG. 2 is a perspective view of the cleaning blade 62. In the cleaning blade 62 in these figures, the support member 621 and the elastic member 624 are shown, and the elastic member 624 of the present embodiment has a strip shape. Further, the blade tip surface 62a, the blade lower surface 62b, and the tip ridge line portion 62c (also referred to as a contact portion, an edge portion, etc.) are shown in the drawing.

In the present invention, the surface in the longitudinal direction of the base material constituting the elastic member, which faces the downstream side in the traveling direction (rotational direction in the present embodiment) of the member to be cleaned, is referred to as the lower surface of the base material, and the tip of the base material. The surface of the tip facing the upstream side in the rotation direction of the member to be cleaned including the ridge is called the tip surface of the base material.
Further, the surface of the elastic member in the longitudinal direction facing the downstream side in the rotation direction of the member to be cleaned is called the lower surface of the blade, and the tip of the tip facing the upstream side in the rotation direction of the member to be cleaned including the tip ridge of the elastic member. The surface is called the blade tip surface.
In FIG. 1, the surface of the member to be cleaned facing the downstream side B in the traveling direction is the blade lower surface 62b, and the surface of the tip facing the upstream side A of the member to be cleaned is the blade tip surface 62a.
Further, the contact portion that comes into contact with the surface of the member to be cleaned of the elastic member includes the tip ridgeline portion of the elastic member. Further, when the tip ridge line portion is turned over or the linear pressure is high, a part of the blade tip surface can also be a contact portion.

<Elastic member>
The elastic member comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned.
The elastic member may have a single-layer structure or a multi-layer structure (for example, a two-layer structure). When the elastic member has a multi-layer structure, the elastic member has, for example, a base material and a surface layer.
The elastic member has a tip ridgeline portion.
The elastic member contains a domain in a region from the surface including the tip ridge line portion to a depth of 100 μm. The average dispersion diameter of the domain is 0.1 μm or more and 5.0 μm or less. The domain is derived from a polysiloxane structure.

In the elastic member, the domain may be contained in a place other than the tip ridge line portion.

The domain is derived from a polysiloxane structure. The polysiloxane structure is derived from, for example, a siloxane compound. The domain is formed, for example, by aggregating siloxane compounds. At that time, the siloxane-based compound forming the domain may or may not be bonded to the matrix component.

The siloxane-based compound indicates a compound having a siloxane bond, and is, for example, silicone. The silicone exists in the form of silicone oil, silicone resin, silicone grease and the like. The siloxane bond has a feature that the bond energy is larger than that of the carbon bond and can exist stably, and the siloxane-based compound has a small surface free energy and is excellent in releasability and lubricity.

As the siloxane compound, a compound made of silicone is preferable, and silicone described later can be used.

The average dispersion diameter of the domain in the region is 0.1 μm or more and 5.0 μm or less. If the average dispersion diameter is less than 0.1 μm, the tip of the blade will be turned over. If the average dispersion diameter exceeds 5.0 μm, deposits will adhere to the blade. If the deposit is toner, a streak image will appear.
The average dispersion diameter is preferably 0.1 μm or more and 3.0 μm or less.

The method for calculating the average dispersion diameter can be obtained by measuring 100 or more dispersion diameters of the domain in a region of 100 μm including an arbitrary tip ridge line portion and using the number average value.
For example, the blade is cut at an arbitrary position to expose the cross section, a region of 100 μm including the tip ridge line is photographed with a laser microscope or SEM, and the dispersion diameter is measured from the image. For the measurement, the dispersion diameter can be calculated from the binarized image using software such as ImagePro.
At this time, it can be confirmed by using EDS (energy dispersive X-ray analysis, Energy dispersive X-ray spectroscopy) or the like that the domain of the observation image is derived from the polysiloxane structure.

The region from the surface including the tip ridge to a depth of 100 μm is a region (Y) as shown in FIGS. 3A to 3D. 3A and 3D are views showing the position of the region (Y), and FIGS. 3B and 3C are enlarged views of the region (Y). In FIGS. 3B and 3C, reference numeral S indicates a domain derived from the polysiloxane structure.
The domains may be distributed over the entire region (Y) as shown in FIG. 3B, or may be distributed over a part of the region (Y) as shown in FIG. 3C. However, when the domain is distributed in a part of the region (Y) as shown in FIG. 3C, it is preferable that the domain is distributed on the surface side of the elastic member 624 in the region (Y).
The elastic member 624 may have a single-layer structure as shown in FIG. 3A, or may have a multi-layer structure as shown in FIG. 3D. In FIG. 3D, the elastic member 624 has a two-layer structure of a surface layer 623 and a base material 622. In FIG. 3D, the region (Y) is present in the surface layer 623.

The tip from ridge portion of the elastic member at the position of 20μm Martens hardness HM (load: 1000μN) is, 1.5 N / mm ² or more 5.0 N / mm ² or less, 2.5 N / mm ² or more 4. 5N / mm ² or less is preferable.
When the Martens hardness is 1.5 N / mm ² or more, it is difficult to be deformed and the tip ridge line portion of the cleaning blade can be suppressed from being turned over. As a result, for example, the deposition of agglomerates derived from the toner external additive on the photoconductor can be suppressed. When the Martens hardness is 5.0 N / mm ² or less, chipping of the blade tip can be suppressed.
The method for measuring the Martens hardness (HM) is as follows.
For the measurement, for example, a microhardness meter HM-2000 manufactured by Fisher Instruments Co., Ltd. is used.
A Vickers indenter is pushed into the tip surface of the base material with a force of 1.0 mN for 10 seconds, held for 5 seconds, and pulled out with a force of 1.0 mN for 10 seconds for measurement.

The measurement location is 20 μm from the tip ridge of the lower surface of the elastic member.
As a measuring method, the tip of the elastic member is cut with a width of about 1 cm, fixed to a slide glass or the like with an adhesive or double-sided tape so that the lower surface faces upward, and the position 20 μm from the tip ridge of the lower surface is measured. ..

The elastic member contains, for example, a layer-constituting resin component and a domain component. In other words, for example, in the elastic member, the domain derived from the polysiloxane structure is dispersed in the layer-constituting resin component. In other words, for example, the elastic member has a sea-island structure in which the layer-constituting resin component is the sea and the domain formed by the aggregation of the polysiloxane structure is the island. The sea-island structure exists, for example, in a region up to a depth of 100 μm from the surface including the tip ridgeline portion.
The layer-forming resin component and the domain component may or may not be bonded by a chemical bond.

In the elastic member, the area ratio of the domain in the cross section of the region (Y) is not particularly limited and may be appropriately selected depending on the intended purpose, but it is 0 in that the effect of the present invention can be further exhibited. .1% or more and 40% or less is preferable, and 0.5% or more and 30% or less is more preferable. When the area ratio is 0.5% or more, the siloxane compound appropriately acts on the reduction of the coefficient of friction with the photoconductor, and the turning of the tip ridge line portion can be further suppressed. When the area ratio is 30% or less, it is possible to further prevent the components of the siloxane compound from moving to the member to be cleaned and contaminating the surface of the member to be cleaned. For example, when the member to be cleaned is a photoconductor, if the area ratio is 30% or less, it is possible to prevent the components of the siloxane compound from moving to the photoconductor and contaminating the surface of the photoconductor to deteriorate the image quality. can do.
The area ratio of the domain in the cross section of the region can be obtained by, for example, the following method. The blade is cut at an arbitrary position to expose the cross section, a region of 100 μm including the tip ridge is photographed with a laser microscope or SEM, and the area ratio occupied by the siloxane compound is calculated from the image. It can be obtained by calculating the area ratio from the binarized image using software such as ImagePro.

The average thickness of the elastic member is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1.0 mm or more and 3.0 mm or less, and more preferably 1.5 mm or more and 2.0 mm or less.

Here, the average film thickness of the elastic member of the abutting portion can be obtained by an arithmetic mean value obtained by measuring 10 arbitrary points of the elastic member in the abutting portion.
The method for measuring the thickness of the elastic member of the abutting portion is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the cut surface including the elastic member of the abutting portion is measured using a microscope. The method etc. can be mentioned.
Specifically, for example, the thickness of the elastic member is measured by observing with a microscope with the blade tip surface facing upward.

When the elastic member has a single-layer structure, the elastic member can be obtained, for example, by curing the following second composition.
The second composition is, for example, an emulsified first composition containing a curing agent made of an active hydrogen compound.

<<< First Composition >>>
The first composition contains at least one of the following components A and B, and component C.
A: NCO-terminated silicone prepolymer B: Silicone oil C: NCO-terminated urethane prepolymer

-A: NCO end-modified silicone prepolymer-
The NCO terminal-modified silicone prepolymer is a prepolymer having an isocyanate group at the end, which is obtained by reacting a modified silicone having at least one hydroxyl group at the end with a first polyisocyanate.

The modified silicone is a silicone having at least one hydroxyl group at the terminal, and a commercially available one can be used.

The modified silicone is selected from those capable of reacting with the first polyisocyanate to form a prepolymer having an NCO group at the end. Specifically, a hydroxyl group-modified silicone is more preferable because it has a hydroxyl group and an amino group at the end and is stable.
Examples of commercially available products include KF-6000, KF-6001, KF-6002, KF-6003, X-22-176F, X-22-176DX, X-22-176GX-A (Shinetsu Silicone) and the like. Types of terminal denaturation include one-end, both-end, and side chains, but one-end denaturation is more desirable from the viewpoint of efficiency of functioning as a surfactant as described later.

The first polyisocyanate is a compound that is bonded to the end of the modified silicone via a urethane bond and has an isocyanate group (NCO) at the end, which will be described in detail later.

The NCO-terminated silicone prepolymer is a silicone prepolymer having an NCO group at the terminal, which is obtained by reacting the modified silicone with the first polyisocyanate. It can be obtained by mixing a first polyisocyanate having about twice the equivalent of the modified silicone side functional group and heating and stirring.

-B: Silicone oil-
The silicone oil is a silicone oil (organopolysiloxane) that is liquid at room temperature, and a commercially available silicone oil can be used.
As the silicone oil, general polyorganosiloxane can be used. Since the silicone oil is stably dispersed in the polyurethane / urea matrix, it is more preferable that the compatibility with the matrix is poor, and such silicone oil is contained in the NCO-terminated urethane prepolymer using, for example, an NCO-terminated silicone prepolymer as a surfactant. Is dispersed in an emulsified state. Most preferred is dimethyl silicone. Dimethyl silicone oil is the most general-purpose silicone oil, and commercially available products of various companies can be used. At the time of emulsification described above, since higher energy is required when the viscosity is high, those having a viscosity of about 1 to 10,000 mPa · s / 25 ° C. can be preferably used.

-C: NCO-terminated urethane prepolymer-
The NCO-terminated urethane prepolymer is a prepolymer having an isocyanate group at the end, which is obtained by reacting a polyol with a second polyisocyanate.

The polyol is, for example, a polyol having a molecular weight of 500 to 4000, and is a so-called long-chain polyol used in the production of polyurethane resins. Polyester polyols, polyether polyols, polycarbonate polyols and the like are preferably used.

The second polyisocyanate is a compound that reacts with the hydroxyl group at the end of the polyol and bonds via a urethane bond to make the end an isocyanate group (NCO).

The polyisocyanate compounds used as the first polyisocyanate and the second polyisocyanate are, for example, m-phenylenediocyanate, p-phenylenediocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,4-. Diisocyanate, diphenylmethane-4,4'-diisocyanate, 3,3'-methoxy-4,4'-diphenyldiisocyanate, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, xylylene-1,4-diisocyanate, 4 , 4'-diphenylpropane diisocyanate, hexamethylene diisocyanate, 3-isocyanate methyl-3,5,5-trimethylcyclohexylisocyanate, dicyclohexylmethane 4,4'-diisocyanate, cyclohexylene-1,2-diisocyanate, cyclohexylene-1, 4-Diisocyanate and the like can be mentioned.

Here, the first polyisocyanate and the second polyisocyanate are preferably selected so that the reactivity with the curing agent is higher in the first polyisocyanate than in the second polyisocyanate. The reactivity of the isocyanate group (R-NCO) increases as the electron attraction of the substituent R increases. Specifically, the reactivity of aromatic polyisocyanate is larger than that of aliphatic polyisocyanate, and the reactivity is lowered by steric hindrance such as methyl group of side chain. These can be inferred from the following literature related to urethane.
Hepburn, C.I. : Polyurethane Elastomers, Applied Science Publicers, (1982)
・ Sanders J. H. , Frisch K. C. : Polyurethanes: Chemistry and technology, Part 1. Chemistry, New York: Interscience Publicers, 170 (1962)
・ Polyurethane resin handbook, edited by Keiji Iwata, Nikkan Kogyo Shimbun (1987)
・ Hardener for polyurethane resin paint, Yoshiaki Takanaka, Japan Society of Color Material, 49 (1976)

As described above, in general, the aromatic polyisocyanate has higher reactivity with the curing agent than the aliphatic or alicyclic polyisocyanate. Therefore, for example, the first polyisocyanate is designated as the aromatic polyisocyanate and the second polyisocyanate is used. The polyisocyanate may be an aliphatic or alicyclic polyisocyanate, but both may be an aromatic polyisocyanate or an aliphatic or alicyclic polyisocyanate.
Specifically, for example, an aromatic polyisocyanate can be used as the first polyisocyanate, and an aliphatic polyisocyanate can be used as the second polyisocyanate. Further, both can be selected from aromatic polyisocyanate or aliphatic polyisocyanate. For example, xylylene diisocyanate (aliphatic highly reactive) as the first polyisocyanate and dicyclohexylmethane 4,4'-as the second polyisocyanate. Combinations such as diisocyanate (aliphatic low reactivity) can be exemplified.

The NCO-terminated urethane prepolymer is a main component that forms a matrix of a cured urethane resin, and can be appropriately synthesized or selected from commercially available products according to the desired physical characteristics. For example, it can be obtained by mixing a long-chain polyol such as a polyester polyol, a polyether polyol, or a polycarbonate polyol having a molecular weight of 500 to 4000 with a second polyisocyanate having an equivalent amount of about twice that of the hydroxyl group on the polyol side, and heating and stirring. .. It can be selected from commercially available products if the requirements for relative reactivity of the NCO-terminated silicone prepolymer with the first polyisocyanate are satisfied.

The first composition contains at least one of component A and component B, and component C, but is in an emulsified state by, for example, mixing. That is, the NCO-terminated silicone prepolymer of component A acts as a surfactant, and the silicone oil of component B can be retained in the NCO-terminated urethane prepolymer of component C in an emulsified state. That is, the NCO-terminated silicone prepolymer is coordinated around the fine particles of the silicone oil to form micelles, which becomes an emulsion dispersed in the NCO-terminated urethane prepolymer.

As described above, the first composition can be, for example, an emulsion in which an NCO-terminal modified silicone prepolymer and a silicone oil are dispersed in an NCO-terminal urethane prepolymer. As the disperser, a general emulsifying device such as a high-speed stirrer or a homogenizer can be used.
By dispersing the NCO-terminated silicone prepolymer in the NCO-terminated urethane prepolymer and then dispersing the silicone oil, a uniform milky white dispersion can be quickly produced.

<<< Second Composition >>>
The second composition is an emulsified first composition containing a curing agent made of an active hydrogen compound.

The curing agent is an active hydrogen-containing compound that is reactive with an NCO group, and is specifically a polyamine or a polyvalent herodoxy compound. When a polyvalent hydroxy compound is used as the curing agent, the matrix resin (layer constituent resin) becomes a polyurethane resin, and when polyamine is used as the curing agent, the matrix resin becomes a polyurethane urea resin. Since it is effective to rapidly react the NCO-terminated silicone prepolymer serving as a shell with the curing agent, a curing agent containing a polyamine equal to or greater than the NCO equivalent of the silicone prepolymer is more preferably used. The multivalent hydroxy compound may be used together with a polyamine as a chain length extender. Further, in order to appropriately proceed with the curing reaction, known urethane curing catalysts (amines, organic metals) can also be used in combination.

Here, as the polyhydric hydroxy compound, an aliphatic polyhydric alcohol is preferably used, and ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexane are preferably used. Illustrate diols, 1,7-heptanediol, 1,8-octanediol, 1,4-cyclohexanedimethanol, 1,4-bis (hydroxyethoxy) benzene, 1,3-bis (hydroxyethoxy) benzene, and the like. Can be done.
Examples of the polyamine compound include 4,4'-methylenebis (2-chloroaniline), diethyltoluenediamine, and dimethylthiotoluenediamine.

The second composition becomes a polyurethane / urea resin cured product by being thermosetting with a predetermined mold or the like.
Here, since the second composition contains an NCO-terminated silicone prepolymer, an NCO-terminated urethane prepolymer, and a curing agent which is an active hydrogen-containing compound reactive with the NCO group, the NCO group and the curing agent are used. By reacting with each other, a cured polyurethane resin product is obtained.

Here, the first polyisocyanate added to the end of the NCO-terminated silicone prepolymer and the second polyisocyanate added to the end of the NCO-terminated urethane prepolymer have first reactivity with a curing agent. It is preferable to use a polyisocyanate having a higher price than the second polyisocyanate. In that case, the NCO-terminated silicone prepolymer forming the micelle first reacts with the curing agent, the silicone oil becomes the core, and the cured product of the NCO-terminated silicone prepolymer becomes the shell to form a core-shell structure. That is, when the NCO-terminated silicone prepolymer forming the micelle first reacts with the curing agent, a pseudo-capsule in which the silicone oil is immobilized in the micelle is formed. After that, the NCO-terminated urethane prepolymer serving as a matrix reacts with the curing agent and is cured, so that the urethane resin cured product has a core-shell structure stably dispersed in the urethane / urea matrix.

<< Surface layer >>
When the elastic member has a surface layer and a base material, the surface layer is obtained, for example, by curing the second composition.

When the elastic member has a surface layer and a base material, the surface layer has a tip ridge line portion. Then, the surface layer contains a domain derived from a polysiloxane structure having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less in a region from the surface including the tip ridge line portion to a depth of 100 μm. Furthermore, from said front edge portion of the surface layer at the position of 20μm Martens hardness HM (load: 1000μN) is 1.5 N / mm ² or more 5.0 N / mm ² or less.

The average thickness of the surface layer is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 30 μm or more and 800 μm or less, and more preferably 50 μm or more and 500 μm or less. Since the average thickness is 50 μm or more, the surface exposed after wear even if worn during long-term use also contains a domain derived from the polysiloxane structure, and the portion that comes into contact with the photoconductor even if worn is always polysiloxane. There is an effect that a domain derived from the structure exists and a low friction coefficient can be maintained. Further, when the average thickness is 500 μm or less, deterioration of dimensional accuracy during processing due to the influence of the surface layer containing the domain derived from the polysiloxane structure can be further suppressed.

<< Base material >>
The base material of the elastic member is not particularly limited in shape, material, size, structure and the like, and can be appropriately selected depending on the purpose.
Examples of the shape include a flat plate shape, a strip shape, a sheet shape, and the like.
The size is not particularly limited and may be appropriately selected depending on the size of the member to be cleaned.
The material of the base material is not particularly limited and may be appropriately selected depending on the intended purpose, but polyurethane rubber, polyurethane elastomer, etc. are preferable from the viewpoint that high elasticity can be easily obtained.
The shape of the base material is, for example, a shape consisting of a pair of plate surfaces facing each other in the thickness direction of the base material and two pairs of end faces orthogonal to the plate surface and facing each other in the in-plane direction of the plate surface. Can be mentioned.

The structure of the base material is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a single-layer structure composed of one kind of material, a two-layer structure in which two different kinds of materials are integrally molded, and a number. Examples include a multi-layer structure in which different types of materials are integrally molded.
When producing the base material in which two or more layers are laminated, delamination does not occur by continuously injecting raw materials having different mixing ratios into a centrifugal molding die before each layer is completely cured. It is possible to integrally mold as such.

The material of the base material is not particularly limited and may be appropriately selected depending on the intended purpose, but urethane rubber is preferable from the viewpoint that high elasticity can be easily obtained.

The method for producing the base material of the elastic member is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a polyurethane prepolymer is prepared using a polyol compound and a polyisocyanate compound, a curing agent and, if necessary, a curing catalyst are added to the polyurethane prepolymer, and the mixture is crosslinked in a predetermined mold and placed in a furnace. After cross-linking, the product is formed into a sheet by centrifugation, left at room temperature, and aged, and the product is cut into a flat plate to a predetermined size.

The polyol compound is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include high molecular weight polyols and low molecular weight polyols.
Examples of the high molecular weight polyol include polyester polyol which is a condensate of alkylene glycol and aliphatic dibasic acid; ethylene adipate ester polyol, butylene adipate ester polyol, hexylene adipate ester polyol, ethylene propylene adipate ester polyol, and ethylene butylene. Polyol-based polyols such as polyester polyols of adipic acid and alkylene glycols such as adipate ester polyols and ethylene neopentylene adipate ester polyols; polycaprolactone-based polyols such as polycaprolactone ester polyols obtained by ring-opening polymerization of caprolactones; Examples thereof include polyether polyols such as oxytetramethylene) glycol and poly (oxypropylene) glycol. These may be used alone or in combination of two or more.

Examples of the low molecular weight polyol include 1,4-butanediol, ethylene glycol, neopentyl glycol, hydroquinone-bis (2-hydroxyethyl) ether, and 3,3'-dichloro-4,4'-diaminodiphenyllmethane. , 4,4'-Diaminodiphenylmethane and other dihydric alcohols; 1,1,1-trimethylolpropane, glycerin, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolethane, 1, Examples thereof include trihydric or higher polyhydric alcohols such as 1,1-tris (hydroxyethoxymethyl) propane, diglycerin and pentaerythritol. These may be used alone or in combination of two or more.

The polyisocyanate compound is not particularly limited and may be appropriately selected depending on the intended purpose. For example, methylene diphenyldiisocyanate (MDI), tolylene diisocyanate (TDI), xylene diisocyanate (XDI), naphthylene 1, 5 -Diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), isophorone diisocyanate (IPDI), hydrogenated xylylene diisocyanate (H6XDI), dicyclohexylmethane diisocyanate (H12MDI), hexamethylene diisocyanate (HDI), diisocyanate dimerate (DDI), Examples thereof include norbornene diisocyanate (NBDI) and trimethylhexamethylene diisocyanate (TMDI). These may be used alone or in combination of two or more.

The curing catalyst is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 2-methylimidazole and 1,2-dimethylimidazole.

The content of the curing catalyst is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 0.01% by mass or more and 0.5% by mass or less, and 0.05% by mass or more and 0.3% by mass. % Or less is more preferable.

The JIS-A hardness of the base material is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 60 degrees or more, more preferably 65 degrees or more and 80 degrees or less. When the JIS-A hardness is 60 degrees or more, the blade linear pressure is easily obtained, and the area of the contact portion with the image carrier is difficult to expand, so that cleaning failure is less likely to occur.
Here, the JIS-A hardness of the base material can be measured using, for example, a micro rubber hardness tester MD-1 manufactured by Polymer Instruments Co., Ltd.

The elastic modulus of the base material conforming to the JIS K6255 standard is not particularly limited and can be appropriately selected depending on the intended purpose. Here, the elastic modulus of the base material conforms to, for example, JIS K6255 standard, and at 23 ° C., No. 1 manufactured by Toyo Seiki Seisakusho Co., Ltd. It can be measured using a 221 resilience tester.

The average thickness of the base material is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1.0 mm or more and 3.0 mm or less.

<Support member>
The cleaning blade is preferably composed of a support member and a flat plate-shaped elastic member having one end connected to the support member and having a free end portion having a predetermined length at the other end. The cleaning blade is arranged so that a contact portion including a tip ridge line portion, which is one end on the free end side of the elastic member, abuts on the surface of the member to be cleaned along the longitudinal direction.

The shape, size, material, and the like of the support member as long as it is a member that supports the elastic member are not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the shape of the support member include a flat plate shape, a strip shape, a sheet shape, and the like. The size of the support member is not particularly limited and may be appropriately selected depending on the size of the member to be cleaned.

Examples of the material of the support member include metal, plastic, ceramic, and the like. Among these, a metal plate is preferable from the viewpoint of strength, and a steel plate such as stainless steel, an aluminum plate, and a phosphor bronze plate are particularly preferable.

<Member to be cleaned>
The material, shape, structure, size, and the like of the member to be cleaned are not particularly limited and may be appropriately selected depending on the intended purpose. Examples of the shape of the member to be cleaned include a drum shape, a belt shape, a flat plate shape, a sheet shape, and the like. The size of the member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose, but a size that is usually used is preferable.

The material of the member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include metal, plastic and ceramic.
The member to be cleaned is not particularly limited and may be appropriately selected depending on the intended purpose. When the cleaning blade is applied to an image forming apparatus, for example, an image carrier and the like can be mentioned.

<Adhesion>
The deposits are not particularly limited as long as they are adhered to the surface of the member to be cleaned and are to be removed by the cleaning blade, and can be appropriately selected according to the purpose. For example, toner and lubricant. , Inorganic fine particles, organic fine particles, dust, dust or a mixture thereof, and the like. Among these, toner is preferable, and low-temperature fixable toner having a glass transition temperature of 50 ° C. or lower is particularly preferable.

(Process cartridge, image forming device and image forming method)
The process cartridge of the present invention has at least an image carrier and cleaning means for removing toner remaining on the image carrier, and the cleaning means has the cleaning blade of the present invention. As a cleaning auxiliary means, a mechanism for applying a lubricant to the surface of the latent image carrier may be provided.

The image forming apparatus of the present invention includes an image carrier, a charging means for charging the surface of the image carrier, an exposure means for exposing the charged image carrier to form an electrostatic latent image, and the electrostatic. A developing means for developing a latent image with toner to form a visible image, a transfer means for transferring the visible image to a recording medium, and a fixing means for fixing the transferred image transferred to the recording medium. It has a cleaning means for removing the toner remaining on the image carrier, and the cleaning means has the cleaning blade of the present invention. The image carrier may be provided with a mechanism for applying a lubricant as a cleaning auxiliary means.

The image forming method of the present invention uses a charging step of charging the surface of the image carrier, an exposure step of exposing the charged image carrier to form an electrostatic latent image, and using toner for the electrostatic latent image. A development step of developing to form a visible image, a transfer step of transferring the visible image to a recording medium, a fixing step of fixing the transfer image transferred to the recording medium, and a fixing step on the image carrier. The cleaning step includes at least a cleaning step of removing residual toner, and the cleaning step is performed using the cleaning blade of the present invention.

Hereinafter, as an image forming apparatus to which the present invention is applied, an embodiment (hereinafter, referred to as an embodiment) of an electrophotographic printer (hereinafter, simply referred to as a printer 500) will be described. First, the basic configuration of the printer 500 according to the present embodiment will be described.

FIG. 4 is a schematic configuration diagram showing the printer 500. The printer 500 includes four image-forming units 1Y, C, M, and K for yellow, magenta, cyan, and black (hereinafter referred to as Y, C, M, and K). These use Y, C, M, and K toners of different colors as the image forming substance for forming an image, but have the same configuration except for the above.

Above the four image forming units 1Y, 1C, 1M, and 1K, a transfer unit 60 including an intermediate transfer belt 14 as an intermediate transfer body is arranged. The toner images of each color formed on the surfaces of the photoconductors 3Y, 3C, 3M, and 3K included in the image forming units 1Y, 1C, 1M, and 1K, which will be described in detail later, are superimposed on the surface of the intermediate transfer belt 14. It is a structure to be transferred.

Further, an optical writing unit 40 is arranged below the four image forming units 1Y, 1C, 1M, and 1K. The optical writing unit 40, which is a latent image forming means, irradiates the photoconductors 3Y, 3C, 3M, and 3K of the image forming units 1Y, 1C, 1M, and 1K with the laser beam L emitted based on the image information. As a result, electrostatic latent images for Y, C, M, and K are formed on the photoconductors 3Y, 3C, 3M, and 3K. The optical writing unit 40 deflects the laser beam L emitted from the light source by the polygon mirror 41 rotationally driven by the motor, and the photoconductors 3Y, 3C, 3M, and 3K pass through a plurality of optical lenses and mirrors. Is to irradiate. Instead of such a configuration, one that performs optical scanning by an LED array can also be adopted.

Below the optical writing unit 40, the first paper feed cassette 151 and the second paper feed cassette 152 are arranged so as to overlap each other in the vertical direction. In each of these paper cassettes, a plurality of transfer papers P, which are recording media, are housed in a stack of paper bundles, and the top transfer paper P contains the first paper feed roller 151a, The second paper feed rollers 152a are in contact with each other. When the first paper feed roller 151a is rotationally driven counterclockwise in the drawing by the driving means, the top transfer paper P in the first paper feed cassette 151 extends in the vertical direction on the right side of the cassette in the drawing. It is discharged toward the paper feed path 153 arranged so as to exist. When the second paper feed roller 152a is rotationally driven counterclockwise in FIG. 4 by the driving means, the top transfer paper P in the second paper feed cassette 152 is discharged toward the paper feed path 153. Will be done.

A plurality of transport roller pairs 154 are arranged in the paper feed path 153. The transfer paper P fed into the paper feed path 153 is conveyed in the paper feed path 153 from the lower side to the upper side in FIG. 4 while being sandwiched between the rollers of the transfer rollers 154.

A resist roller pair 55 is arranged at the downstream end of the paper feed path 153 in the transport direction. The resist roller pair 55 temporarily stops the rotation of both rollers as soon as the transfer paper P sent from the transport roller pair 154 is sandwiched between the rollers. Then, the transfer paper P is sent out toward the secondary transfer nip, which will be described later, at an appropriate timing.

FIG. 5 is a configuration diagram showing a schematic configuration of one of the four image forming units 1.
As shown in FIG. 5, the image forming unit 1 includes a drum-shaped photoconductor 3 as an image carrier. Although the photoconductor 3 has a drum-like shape, it may have a sheet-like shape or an endless belt-like shape.
A charging roller 4, a developing device 5, a primary transfer roller 7, a cleaning device 6, a lubricant applying device 10, a static elimination lamp, and the like are arranged around the photoconductor 3. The charging roller 4 is a charging member included in the charging device as the charging means, and the developing device 5 is a developing means for forming a latent image formed on the surface of the photoconductor 3 into a toner image. The primary transfer roller 7 is a primary transfer member provided in the primary transfer device as a primary transfer means for transferring the toner image on the surface of the photoconductor 3 to the intermediate transfer belt 14. The cleaning device 6 is a cleaning means for cleaning the toner remaining on the photoconductor 3 after the toner image is transferred to the intermediate transfer belt 14. The lubricant application device 10 is a lubricant application means for applying a lubricant on the surface of the photoconductor 3 after the cleaning device 6 has cleaned it. The static elimination lamp is a static elimination means for statically eliminating the surface potential of the photoconductor 3 after cleaning. In FIG. 5, reference numeral 8 represents a cleaning roller.

The charging roller 4 is arranged on the photoconductor 3 at a predetermined distance in a non-contact manner, and charges the photoconductor 3 to a predetermined polarity and a predetermined potential. The surface of the photoconductor 3 uniformly charged by the charging roller 4 is irradiated with laser light L from the optical writing unit 40, which is a latent image forming means, based on the image information to form an electrostatic latent image.

The developing device 5 has a developing roller 51 as a developing agent carrier. A development bias is applied to the developing roller 51 from a power source. Inside the casing of the developing apparatus 5, a supply screw 52 and a stirring screw 53 for stirring the developer contained in the casing while being conveyed in opposite directions are provided. In addition, a doctor 54 for regulating the developer carried on the developing roller 51 is also provided. The toner in the developer, which is stirred and conveyed by the two screws of the supply screw 52 and the stirring screw 53, is charged to a predetermined polarity. Then, the developer is pumped onto the surface of the developing roller 51, and the pumped developer is regulated by the doctor 54, and the toner adheres to the latent image on the photoconductor 3 in the developing region facing the photoconductor 3. ..

The cleaning device 6 has a fur brush 101, a cleaning blade 62, and the like. The cleaning blade 62 is in contact with the photoconductor 3 in the counter direction with respect to the surface movement direction of the photoconductor 3. The cleaning blade 62 is the cleaning blade of the present invention. The lubricant coating device 10 includes a solid lubricant 103, a lubricant pressure spring 103a, and the like, and uses a fur brush 101 as a coating brush for applying the solid lubricant 103 onto the photoconductor 3. The solid lubricant 103 is held by the bracket 103b and is pressurized to the fur brush 101 side by the lubricant pressure spring 103a. Then, the solid lubricant 103 is scraped by the fur brush 101 that rotates in the circumferential direction with respect to the rotation direction of the photoconductor 3, and the lubricant is applied onto the photoconductor 3. It is preferable that the coefficient of static friction on the surface of the photoconductor 3 is maintained at 0.2 or less during non-image formation by applying a lubricant to the photoconductor.

The charging device of the present embodiment is a non-contact proximity arrangement method in which the charging roller 4 is placed close to the photoconductor 3, and the charging device includes a corotron, a scorotron, and a solid state charger. A known configuration can be used. Among these charging methods, the contact charging method or the non-contact close placement method is more desirable, and has merits such as high charging efficiency, low ozone generation amount, and miniaturization of the apparatus.

The light source of the laser light L of the optical writing unit 40 and the light source such as the static elimination lamp include a fluorescent lamp, a tungsten lamp, a halogen lamp, a mercury lamp, a sodium lamp, a light emitting diode (LED), a semiconductor laser (LD), and electroluminescence (EL). ) And other luminescent materials in general can be used.
Further, in order to irradiate only light in a desired wavelength range, various filters such as a sharp cut filter, a bandpass filter, a near infrared cut filter, a dichroic filter, an interference filter, and a color temperature conversion filter can also be used.
Of these light sources, light emitting diodes and semiconductor lasers are well used because they have high irradiation energy and long wavelength light of 600 to 800 nm.

The transfer unit 60, which is a transfer means, includes a belt cleaning unit 162, a first bracket 63, a second bracket 64, and the like, in addition to the intermediate transfer belt 14. Further, four primary transfer rollers 7Y, 7C, 7M, 7K, a secondary transfer backup roller 66, a drive roller 67, an auxiliary roller 68, a tension roller 69 and the like are also provided. The intermediate transfer belt 14 is endlessly moved counterclockwise in the drawing by the rotational drive of the drive roller 67 while being stretched on these eight roller members. The four primary transfer rollers 7Y, C, M, and K each form a primary transfer nip by sandwiching the intermediate transfer belt 14 that can be moved endlessly between the photoconductors 3Y, 3C, 3M, and 3K. .. Then, a transfer bias having the opposite polarity (for example, plus) to the toner is applied to the back surface (loop inner peripheral surface) of the intermediate transfer belt 14. The intermediate transfer belt 14 is on the photoconductors 3Y, 3C, 3M, 3K on its front surface in the process of sequentially passing through the primary transfer nips for Y, C, M, and K as it moves endlessly. The Y, C, M, and K toner images are superimposed and primary transferred. As a result, a four-color superimposed toner image (hereinafter referred to as a four-color toner image) is formed on the intermediate transfer belt 14.

The secondary transfer backup roller 66 forms a secondary transfer nip by sandwiching the intermediate transfer belt 14 with the secondary transfer roller 70 arranged on the outer side of the loop of the intermediate transfer belt 14. The resist roller pair 55 described above sends out the transfer paper P sandwiched between the rollers toward the secondary transfer nip at a timing capable of synchronizing with the four-color toner image on the intermediate transfer belt 14. The four-color toner image on the intermediate transfer belt 14 is affected by the secondary transfer electric field formed between the secondary transfer roller 70 to which the secondary transfer bias is applied and the secondary transfer backup roller 66 and the nip pressure. , The secondary transfer is collectively transferred to the transfer paper P in the secondary transfer nip. Then, in combination with the white color of the transfer paper P, a full-color toner image is obtained.

The transfer residual toner that has not been transferred to the transfer paper P adheres to the intermediate transfer belt 14 after passing through the secondary transfer nip. It is cleaned by the belt cleaning unit 162. In the belt cleaning unit 162, the belt cleaning blade 162a is brought into contact with the front surface of the intermediate transfer belt 14, thereby scraping and removing the transfer residual toner on the intermediate transfer belt 14.

The first bracket 63 of the transfer unit 60 swings at a predetermined rotation angle about the rotation axis of the auxiliary roller 68 as the solenoid drive is turned on and off. When forming a monochrome image, the printer 500 rotates the first bracket 63 slightly counterclockwise in the drawing by driving the above-mentioned solenoid. By this rotation, the primary transfer rollers 7Y, 7C, 7M for Y, C, M are revolved counterclockwise in the figure around the rotation axis of the auxiliary roller 68, so that the intermediate transfer belt 14 is rotated around the Y, C, M. Separated from the photoconductors 3Y, 3C, 3M for M. Then, of the four image forming units 1Y, 1C, 1M, and 1K, only the image forming unit 1K for K is driven to form a monochrome image. As a result, it is possible to avoid consumption of each member constituting the image-forming unit due to unnecessary driving of the image-forming units for Y, C, and M when forming a monochrome image.

A fixing unit 80 is arranged above the secondary transfer nip in the drawing. The fixing unit 80 includes a pressure heating roller 81 including a heat generating source such as a halogen lamp, and a fixing belt unit 82. The fixing belt unit 82 includes a fixing belt 84 as a fixing member, a heating roller 83 including a heat generating source such as a halogen lamp, a tension roller 85, a drive roller 86, a temperature sensor, and the like. Then, the endless fixing belt 84 is moved endlessly in the counterclockwise direction in the drawing while being stretched by the heating roller 83, the tension roller 85, and the drive roller 86. In the process of this endless movement, the fixing belt 84 is heated from the back surface side by the heating roller 83. A pressure heating roller 81, which is rotationally driven in the clockwise direction in the drawing, is in contact with the portion where the fixing belt 84, which is heated in this way, is hung on the heating roller 83 from the front surface side. As a result, a fixing nip is formed in which the pressure heating roller 81 and the fixing belt 84 come into contact with each other.

A temperature sensor is arranged on the outside of the loop of the fixing belt 84 so as to face the front surface of the fixing belt 84 via a predetermined gap, and the surface temperature of the fixing belt 84 immediately before entering the fixing nip. Is detected. This detection result is sent to the fixed power supply circuit. The fixing power supply circuit controls on / off of power supply to the heat generation source included in the heating roller 83 and the heat generation source included in the pressurizing heating roller 81 based on the detection result by the temperature sensor.

The transfer paper P that has passed through the secondary transfer nip described above is separated from the intermediate transfer belt 14 and then sent into the fixing unit 80. Then, in the process of being conveyed from the lower side to the upper side in the drawing while being sandwiched between the fixing nips in the fixing unit 80, the full-color toner image is fixed to the transfer paper P by being heated and pressed by the fixing belt 84. NS.

The transfer paper P thus fixed is discharged to the outside of the machine after passing between the paper ejection rollers and the rollers 87. A stack portion 88 is formed on the upper surface of the housing of the printer 500 main body, and the transfer paper P discharged to the outside of the machine by the paper discharge roller pair 87 is sequentially stacked on the stack portion 88.

Four toner cartridges 100Y, 100C, 100M, 100K for accommodating Y, C, M, and K toners are arranged above the transfer unit 60. The Y, C, M, K toners in the toner cartridges 100Y, 100C, 100M, 100K are appropriately supplied to the developing apparatus of the image forming unit 1Y, 1C, 1M, 1K. These toner cartridges 100Y, 100C, 100M, 100K can be attached to and detached from the printer body independently of the image forming units 1Y, 1C, 1M, 1K.

Next, the image forming operation in the printer 500 will be described.
When a print execution signal is received from the operation unit or the like, a predetermined voltage or current is sequentially applied to the charging roller 4 and the developing roller 51 at predetermined timings, respectively. Similarly, a predetermined voltage or current is sequentially applied to a light source such as the optical writing unit 40 and the static elimination lamp at a predetermined timing. Further, in synchronization with this, the photoconductor 3 is rotationally driven in the direction of the arrow in the drawing by the photoconductor drive motor as a driving means.

When the photoconductor 3 rotates in the direction of the arrow in the drawing, the surface of the photoconductor 3 is first uniformly charged to a predetermined potential by the charging roller 4. Then, the laser beam L corresponding to the image information is irradiated onto the photoconductor 3 from the optical writing unit 40, and the portion of the surface of the photoconductor 3 irradiated with the laser beam L is statically eliminated to form an electrostatic latent image. ..

The surface of the photoconductor 3 on which the electrostatic latent image is formed is rubbed by a magnetic brush of a developer formed on the developing roller 51 at a portion facing the developing device 5. At this time, the negatively charged toner on the developing roller 51 is moved to the electrostatic latent image side by a predetermined development bias applied to the developing roller 51, and is made into a toner image (development). A similar image-forming process is executed in each image-forming unit 1, and toner images of each color are formed on the surfaces of the photoconductors 3Y, 3C, 3M, and 3K of each image-forming unit 1Y, 1C, 1M, and 1K. ..

As described above, in the printer 500, the electrostatic latent image formed on the photoconductor 3 is reverse-developed by the developing device 5 with the negatively charged toner. In the present embodiment, an example using the non-contact electrification roller method of N / P (negative / positive: toner adheres to a place where the potential is low) has been described, but the present invention is not limited to this.

The toner images of each color formed on the surfaces of the photoconductors 3Y, 3C, 3M, and 3K are sequentially primary-transferred so as to overlap on the surface of the intermediate transfer belt 14. As a result, a four-color toner image is formed on the intermediate transfer belt 14.

The four-color toner image formed on the intermediate transfer belt 14 is fed from the first paper cassette 151 or the second paper cassette 152, and is fed to the secondary transfer nip via the rollers of the resist roller vs. 55. It is transferred to the transfer paper P to be transferred. At this time, the transfer paper P is temporarily stopped in a state of being sandwiched between the resist roller pairs 55, and is supplied to the secondary transfer nip in synchronization with the tip of the image on the intermediate transfer belt 14. The transfer paper P on which the toner image is transferred is separated from the intermediate transfer belt 14 and conveyed to the fixing unit 80. Then, when the transfer paper P on which the toner image is transferred passes through the fixing unit 80, the toner image is fixed on the transfer paper P by the action of heat and pressure, and the transfer paper P on which the toner image is fixed is a printer. It is discharged to the outside of the 500 apparatus and stacked on the stack portion 88.

On the other hand, on the surface of the intermediate transfer belt 14 on which the toner image is transferred to the transfer paper P by the secondary transfer nip, the transfer residual toner on the surface is removed by the belt cleaning unit 162.
Further, on the surface of the photoconductor 3 on which the toner images of each color were transferred to the intermediate transfer belt 14 by the primary transfer nip, the residual toner after the transfer was removed by the cleaning device 6, and the lubricant was applied by the lubricant applying device 10. After that, the static electricity is removed by the static elimination lamp.

As shown in FIG. 5, the image forming unit 1 of the printer 500 includes a photoconductor 3, a charging roller 4, a developing device 5, a cleaning device 6, a lubricant coating device 10, and the like as process means in the frame 2. .. The image forming unit 1 can be integrally attached to and detached from the printer 500 main body as a process cartridge. In the printer 500, the image forming unit 1 integrally replaces the photoconductor 3 as a process cartridge and the process means, but the photoconductor 3, the charging roller 4, the developing device 5, the cleaning device 6, and the lubrication The configuration may be such that the agent coating device 10 is replaced with a new one in units.

Next, a toner suitable for the printer 500 to which the present invention is applied will be described.
As the toner used in the printer 500, in order to improve the image quality, it is preferable to use a polymerized toner produced by a suspension polymerization method, an emulsion polymerization method, or a dispersion polymerization method in which the circularity and the particle size are easily reduced. In particular, it is preferable to use a polymerized toner having a circularity of 0.97 or more and a volume average particle size of 5.5 μm or less. A higher resolution image can be formed by using an image having an average circularity of 0.97 or more and a volume average particle size of 5.5 μm or less.

The "circularity" here is an average circularity measured by a flow-type particle image analyzer FPIA-2000 (manufactured by Toa Medical Electronics Co., Ltd.). Specifically, 0.1 to 0.5 ml of a surfactant, preferably an alkylbenzenesulfonate, as a dispersant is added to 100 to 150 ml of water in which the impure solid matter has been removed in advance in the container, and a measurement sample (toner) is further added. ) Is added in an amount of about 0.1 to 0.5 g. Then, the suspension in which the toner was dispersed was dispersed in an ultrasonic disperser for about 1 to 3 minutes so that the concentration of the dispersion was 3000 to 1 [10,000 / μl]. And measure the shape and distribution of the toner. Then, based on this measurement result, the outer peripheral length of the actual toner projection shape shown in FIG. 5A is C1, the projected area (particle projected area) is S, and the perfect circle shown in FIG. 5B having the same area as the projected area S. C2 / C1 was obtained when the outer peripheral length (peripheral length) of was C2, and the average value thereof was defined as circularity.

The volume average particle size can be determined by the Coulter counter method. Specifically, the toner number distribution and volume distribution data measured by the Coulter Multisizer 2e type (manufactured by Coulter Co., Ltd.) are sent to a personal computer via an interface (manufactured by Nikkaki Co., Ltd.) for analysis.
A specific example of the analysis method will be described. A 1% NaCl aqueous solution using primary sodium chloride is prepared as an electrolytic solution. Then, 0.1 to 5 ml of a surfactant, preferably an alkylbenzenesulfonate, is added as a dispersant to 100 to 150 ml of this electrolytic aqueous solution. Further, 2 to 20 mg of toner as a test sample is added thereto, and the mixture is dispersed in an ultrasonic disperser for about 1 to 3 minutes.
Then, 100 to 200 ml of the electrolytic aqueous solution is placed in another beaker, the solution after the dispersion treatment is added to the beaker so as to have a predetermined concentration, and the solution is applied to the Coulter Multisizer 2e type.
An aperture of 100 μm is used, and the particle size of 50,000 toner particles is measured.
The channels are: 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.0 to less than 5.04 μm; 5.04 to less than 6.35 μm; 6 .35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.0 to less than 20.20 μm; 20.20 to 25. Less than 40 μm; 25.40 to less than 32.00 μm; 13 channels of 32.00 to less than 40.30 μm are used, and toner particles having a particle size of 2.00 μm or more and 32.0 μm or less are targeted.

Then, the volume average particle diameter is calculated based on the relational expression "volume average particle diameter = ΣXfV / ΣfV". However, "X" is the representative diameter in each channel, "V" is the equivalent volume in the representative diameter of each channel, and "f" is the number of particles in each channel.

Hereinafter, specific examples of the present invention will be described. The present invention is not limited to these examples.

The examples and comparative examples shown below were evaluated by changing the material for forming the elastic member (curable composition), the dispersion diameter of the domain derived from the polysiloxane structure, the Martens hardness HM at the tip of the blade, and the like. It is a thing.

<Base material of elastic member>
As the base material of the elastic member, urethane rubber having the following JIS-A hardness, 23 ° C. rebound resilience and Martens hardness (HM) was produced by centrifugation.
JIS-A hardness: 75 °
23 ° C elastic modulus: 45%
Martens hardness (HM): 0.9N / mm ²
The measurement method is shown below.

<< JIS-A hardness of the base material >>
The JIS-A hardness on the lower surface side of the base material of the elastic member was measured according to JIS K6253 using a micro rubber hardness tester MD-1 manufactured by Kosei Keiki Co., Ltd. (23 ° C.).

<< Repulsive modulus of base material >>
The elastic modulus of the base material of the elastic member was 23 ° C., and No. 1 manufactured by Toyo Seiki Seisakusho Co., Ltd. Measurements were made according to JIS K6255 using a 221 resilience tester. The sample used was a stack of two sheets having a thickness of 2 mm so as to have a thickness of 4 mm or more.

<Formation of elastic member or surface layer>
The materials used in the curable composition for forming the elastic member or surface layer are shown below.
-Isocyanate-
-MDI (4,4'-diphenylmethane diisocyanate): "Millionate MT" manufactured by Tosoh
・ Hydrogenated MDI (dicyclohexylmethane 4,4'-diisocyanate): manufactured by Tokyo Chemical Industry ・ TDI (2,4-tolylene diisocyanate): "Coronate T-100" manufactured by Toso ・ TODI (o-tolylene diisocyanate) : Made by Nippon Soda

-Polyol-
-PTMG (polytetramethylene ether glycol): "PTMG1000" manufactured by Mitsubishi Chemical Corporation
-PCL (polycaprolactone diol): Daicel's "Plaxel 220"

-Hardener-
・ DETDA (Etacure 100): Mitsui Chemical Fine ・ DMTDA (Etacure 300): Mitsui Chemical Fine ・ BD (1,4-butanediol): Made by Mitsubishi Chemical ・ TMP (Trimethylolpropane): Made by Mitsubishi Gas Chemical

-Siloxane compound-
・ X-22-176DX: Shin-Etsu Silicone single-ended carbinol-modified silicone oil ・ KF6000: Shin-Etsu Silicone double-ended carbinol-modified silicone oil ・ KF96-3000cs: Shin-Etsu Silicone dimethyl silicone oil

-Synthesis of NCO-terminated silicone prepolymer (prepolymer A)-
As shown in Table 1 below, isocyanate and modified silicone oil were mixed and reacted at 60 ° C. for 90 minutes so as to obtain a desired NCO%, and NCO-terminated silicone prepolymers A1 and A2 were prepared.

表１中、「１７６−ＤＸ」は、Ｘ−２２−１７６ＤＸを示す。

In Table 1, "176-DX" indicates X-22-176DX.

-Synthesis of NCO-terminated urethane prepolymer (prepolymer B)-
As shown in Table 2 below, isocyanate and polyol are mixed so as to have a desired NCO%, and reacted with 0.01 g of tin-catalyzed dibutyltin dilaurylate at 80 ° C. for 90 minutes to obtain NCO-terminated urethane prepolymers B1 to B3. Was prepared.

表２中、「ＰＣＬ２２０」は、プラクセル２２０を表す。

In Table 2, "PCL220" represents Praxel 220.

-Preparation of hardener-
Curing agents 1 to 3 were prepared as shown in Table 3 below.

(Example 1)
The prepolymer A1, the prepolymer B1 and the silicone oil were mixed in the formulations shown in Table 4-1 and stirred with a homogenizer (15000 rpm) to obtain a first composition. The stirring conditions at this time are shown in Table 4-1.
A curing agent 1 is added to the first composition heated to 80 ° C. and emulsified with silicone oil, injected into a centrifugal drum heated to 120 ° C. (curing temperature), and reacted for 30 minutes to obtain a rubber sheet. rice field.
The mixing of the first composition and the curing agent was adjusted so that the R value (NCO group / OH group molar ratio) was 0.925.

<Manufacturing of cleaning blade 1>
An elastic member was obtained by cutting out a strip shape from the rubber sheet so that it could be mounted on a color multifunction device (imagio MP C4500, manufactured by Ricoh Co., Ltd.), and the elastic member was fixed to a sheet metal holder (support member) with an adhesive.

Various characteristics of the produced elastic member and cleaning blade were measured as follows. The results are shown in Table 5-1.

<Average dispersion diameter of domains derived from polysiloxane structure>
The elastic member was sliced in a plane orthogonal to the longitudinal direction, and the cross section was turned upward, and a region of 100 μm including the tip ridge line was observed with a laser microscope OLS4100 (manufactured by Olympus Corporation).
As a method of cutting the elastic member into round slices, the elastic member was cut with a razor perpendicular to the longitudinal direction of the elastic member so that the thickness of the elastic member in the longitudinal direction was 3 mm. At that time, if a vertical slicer is used, the cross section can be cut more cleanly.
For the observed image, the dispersion diameter of the domain was measured using ImagePro ver5.1. The length of the line segment connecting two points on the outer circumference of the domain observed in the cross section and passing through the center of gravity of the domain was measured in 2 degree increments. The average value of the measured line segment lengths was taken as the dispersion diameter of the domain. The dispersion diameter of 100 to 200 domains was measured, the number average value was calculated, and this was used as the average dispersion diameter.

<Domain area ratio (%)>
For the area ratio of the domain in the cross section of the 100 μm region including the tip ridge, the elastic member is cut at the relevant portion to expose the cross section, and the 100 μm region including the tip ridge is photographed with a laser microscope OLS4100 (manufactured by Olympus). , It was obtained by calculating the area ratio occupied by the siloxane compound from the image. The area ratio was calculated from the binarized image using ImagePro.

<Average thickness of elastic member or surface layer>
Observation was performed with a digital microscope VHX-2000 (manufactured by KEYENCE CORPORATION) with the tip surface of the cleaning blade in the examples facing upward. Ten points were observed, and the arithmetic mean value was taken as the average thickness.

<Martens hardness of cleaning blade>
For the Martens hardness (HM) of the cleaning blade on the lower surface of the cleaning blade, a Vickers indenter was pushed in with a force of 1.0 mN for 10 seconds and held for 5 seconds using a microhardness meter HM-2000 manufactured by Fischer Instruments. It was pulled out for 10 seconds with a force of 0.0 mN and measured. The measurement position was 20 μm from the tip ridge of the lower surface of the blade, and the measurement was performed so that the Vickers indenter was in contact with the elastic member or the surface layer. The measurement location was the position excluding the 2 cm portions at both ends.

<Assembly of image forming device>
The produced cleaning blade 1 was attached to a color multifunction device (imageo MP C4500, manufactured by Ricoh Co., Ltd.) (the printer unit has the same configuration as the image forming apparatus 500 shown in FIG. 4), and the image forming apparatus of Example 1 was assembled.
The cleaning blade was attached to the image forming apparatus so that the linear pressure was 20 g / cm and the cleaning angle was 79 °. Further, although the above-mentioned apparatus is provided with a lubricant coating apparatus on the surface of the photoconductor, the lubricant coating apparatus was removed and the evaluation was carried out.

<Image formation conditions>
Using the image forming apparatus, the laboratory environment: 65% RH at 21 ° C., paper passing conditions: 5% image area ratio, 3 prints / job, 50,000 sheets (A4 size horizontal) are output, and the following In this way, after passing 50,000 sheets, various characteristics were evaluated. The results are shown in Table 6-1.

<< Cleaning property >>
As an evaluation image, a vertical band pattern (with respect to the paper traveling direction) 43 mm width, 3 charts are output in 20 sheets in A4 size, and the obtained image is visually observed. The cleanability was evaluated. Below, "◎", "○", and "△" are acceptable, and "×" is unacceptable.

[Evaluation criteria]
⊚: Toner that has slipped out due to poor cleaning cannot be visually confirmed on the photoconductor even on the printing paper, and even if the photoconductor is observed with a microscope in the longitudinal direction, the toner streaks cannot be confirmed.
◯: Toner that has slipped out due to poor cleaning cannot be visually confirmed on the printing paper or the photoconductor.
Δ: Toner that has slipped out due to poor cleaning does not exist on the printing paper, but can be visually confirmed on the photoconductor.
X: Toner that has slipped out due to poor cleaning can be visually confirmed on the printing paper and the photoconductor.

In addition, the edge of the blade after evaluation was observed under a microscope and evaluated according to the following evaluation criteria.
[Evaluation criteria]
◯: No chipping of edges or toner sticking in the entire area of the cleaning blade △: Fine toner sticking to the edges (results of △ or higher in the above cleaning property evaluation)
□: There is a minute chip on the edge (result of △ or more in the above cleaning property evaluation)
X: Toner sticks to the edge (result of × in the above cleaning property evaluation)
*: The edge is chipped (result of x in the above cleaning property evaluation)

<< Whiteout image evaluation >>
Using the image forming apparatus, HH environment: 90% RH at 27 ° C., paper passing conditions: vertical band pattern (relative to the paper traveling direction) 30 mm width, 2 charts in A4 size, 2 prints / job, 3 After outputting 000 sheets, a halftone image was printed, and the presence or absence of abnormality in the image was evaluated according to the following evaluation criteria.
Below, "○" and "△" are acceptable, and "×" is unacceptable.
[Evaluation criteria]
◯: There is no white spot in the image.
Δ: Fine streaky white spots occurred, but there was no problem in actual use.
X: A large number of streaky white spots occurred over the entire surface.

<< Photoreceptor Contamination Evaluation >>
Using the image forming apparatus, after leaving the image in a high temperature and high humidity environment: 45 ° C. at 95% RH for 10 days, a laboratory environment: 65% RH at 21 ° C., paper passing condition: a halftone image is printed, and the image is used. The presence or absence of abnormalities was evaluated according to the following evaluation criteria.
Below, "◎", "○", and "△" are acceptable, and "×" is unacceptable.
[Evaluation criteria]
⊚: There are no horizontal streaks in the image.
◯: White horizontal streaks appeared in the image, but disappeared in the 2nd to 5th images.
Δ: White horizontal streaks appeared in the image, but disappeared in the 6th to 10th images.
X: White horizontal streaks appeared in the image and did not disappear until the 10th image.

<< Abnormal noise >>
Using the image forming apparatus, LL environment: 15% RH at 10 ° C., paper passing condition: image area ratio 5% When 50 sheets (A4 size horizontal) of charts are output in 3 prints / jobs, the human ear The presence or absence of abnormal noise was confirmed and the presence or absence of system abnormality was judged as follows. At this time, even if there was a difference in sound such as high frequency or low frequency, the presence or absence of occurrence as an abnormal sound was evaluated regardless of the sound emitted from the blade. Below, "○" and "△" are acceptable, and "×" is unacceptable.

[Evaluation criteria]
○: No abnormal noise is generated △: Abnormal noise is generated, but there is no problem in actual use ×: Abnormal noise is generated and an error occurs due to the torque increase of the photoconductor drum during paper passing (blade If it is turned over, the torque of the blade and the photoconductor will increase, causing an error that the photoconductor drum will stop.)

(Examples 2 to 5, Comparative Examples 2 to 4, Comparative Example 6)
In Example 1, the time of the first composition and the curing agent, the homogenizer, and the curing temperature are changed to the time of the first composition and the curing agent, the homogenizer shown in Tables 4-1 and 4-2, and the curing temperature. A cleaning blade was produced in the same manner as in Example 1 except for the above.
Various characteristics were measured in the same manner as in Example 1. The results are shown in Table 5-1 and Table 5-2.
The evaluation was performed in the same manner as in Example 1. The results are shown in Table 6-1 and Table 6-2.

(Example 6)
The prepolymer B3 and the silicone oil were mixed in the formulations shown in Table 4-1 and stirred with a homogenizer (15000 rpm) to obtain a first composition. The stirring conditions at this time are shown in Table 4-1.
The curing agent 3 was added to the first composition heated to 80 ° C. and emulsified with silicone oil, and injected into a centrifugal drum heated to 130 ° C. (curing temperature) on which the substrate was formed for 30 minutes. The reaction was carried out to obtain a rubber sheet having a surface layer.
The mixing of the first composition and the curing agent was adjusted so that the R value (NCO group / OH group molar ratio) was 0.925.
Others were prepared in the same manner as in Example 1.
Various characteristics were measured in the same manner as in Example 1. The results are shown in Table 5-1.
The evaluation was performed in the same manner as in Example 1. The results are shown in Table 6-1.

(Example 7, Comparative Example 5)
In Example 6, the time of the first composition and the curing agent, the homogenizer, and the curing temperature are changed to the time of the first composition and the curing agent, the homogenizer shown in Tables 4-1 and 4-2, and the curing temperature. A cleaning blade was produced in the same manner as in Example 6 except for the above.
For the blade of Comparative Example 5, the terminal carbinol-modified silicone oil KF6000 was mixed when the urethane prepolymer B was prepared, and at the same time, a prepolymer in which urethane and silicone were mixed was prepared. Others were prepared in the same manner as in Example 6.
Various characteristics were measured in the same manner as in Example 1. The results are shown in Table 5-1 and Table 5-2.
The evaluation was performed in the same manner as in Example 1. The results are shown in Table 6-1 and Table 6-2.

(Comparative Example 1)
A strip shape was cut out so that the urethane rubber base material could be mounted on a color multifunction device (imageo MP C4500, manufactured by Ricoh Co., Ltd.), and fixed to a sheet metal holder (support member) with an adhesive. From the above, a cleaning blade having an elastic member was produced.
Various characteristics were measured in the same manner as in Example 1. The results are shown in Table 5-2.
The evaluation was performed in the same manner as in Example 1. The results are shown in Table 6-2.

表４−１及び表４−２中、ＫＦ９６は、ＫＦ９６−３０００ｃｓを示す。

In Table 4-1 and Table 4-2, KF96 represents KF96-3000cs.

Aspects of the present invention are, for example, as follows.
<1> A cleaning blade having an elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned.
The elastic member has a tip ridgeline portion and has a tip ridgeline portion.
The elastic member contains a domain derived from a polysiloxane structure having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less in a region from the surface including the tip ridge line portion to a depth of 100 μm.
The tip from ridge portion of the elastic member at the position of 20μm Martens hardness HM (load: 1000μN) is 1.5 N / mm ² or more 5.0 N / mm ² or less,
It is a cleaning blade characterized by this.
<2> The cleaning blade according to <1>, wherein the area ratio of the domain in the cross section of the region is 0.5% or more and 30% or less.
<3> The cleaning blade according to any one of <1> to <2>, wherein the domain has a polysiloxane structure derived from an NCO-terminated silicone prepolymer.
<4> A process cartridge having at least an image carrier and a cleaning means for removing toner remaining on the image carrier.
The process cartridge is characterized in that the cleaning means has the cleaning blade according to any one of <1> to <3>.
<5> An image carrier, a charging means for charging the surface of the image carrier, and a charging means.
An exposure means that exposes the charged image carrier to form an electrostatic latent image,
A developing means for developing a visible image by developing the electrostatic latent image with toner, and
A transfer means for transferring the visible image to a recording medium,
A fixing means for fixing the transferred image transferred to the recording medium, and
An image forming apparatus comprising a cleaning means for removing toner remaining on the image carrier.
The image forming apparatus is characterized in that the cleaning means has the cleaning blade according to any one of <1> to <3>.

The cleaning blades described in <1> to <3>, the process cartridge described in <4>, and the image forming apparatus described in <5> solve the above-mentioned problems in the past, and the present invention. The purpose can be achieved.

1 Image-forming unit 2 Frame 3 Photoconductor 4 Charging roller 5 Developing device 6 Cleaning device 7 Primary transfer roller 10 Lubricating device 14 Intermediate transfer belt 40 Optical writing unit 41 Polygon mirror 51 Developing roller 52 Supply screw 53 Stirring screw 54 Doctor 55 Resist Roller vs. 60 Transfer Unit 62 Cleaning Blade 62a Blade Tip Surface 62b Blade Bottom Side 62c Tip Ridge 621 Support Member 622 Base Material 623 Surface Layer 624 Elastic Member 63 First Bracket 64 Second Bracket 66 Secondary Transfer Backup Roller 67 Drive Roller 68 Auxiliary roller 69 Tension roller 70 Secondary transfer roller 80 Fixing unit 81 Pressurized heating roller 82 Fixing belt unit 84 Fixing belt 83 Heating roller 85 Tension roller 86 Drive roller 87 Paper discharge roller vs. 88 Stack part 100 Toner cartridge 101 Fur brush 103 Solid Lubricants 103a Lubricants Pressurized Spring 103b Bracket 123 Image Carrier 151 First Paper Cassette 151a First Paper Roller 152 Second Paper Cassette 152a Second Paper Roller 153 Paper Channel 154 Conveying Roller vs. 162 Belts Cleaning unit 162a Belt cleaning blade 500 Image forming device (printer)

Japanese Patent No. 28773111

Claims (5)

A cleaning blade having an elastic member that comes into contact with the surface of the member to be cleaned and removes deposits adhering to the surface of the member to be cleaned.
The elastic member has a tip ridgeline portion and has a tip ridgeline portion.
The elastic member contains a domain derived from a polysiloxane structure having an average dispersion diameter of 0.1 μm or more and 5.0 μm or less in a region from the surface including the tip ridge line portion to a depth of 100 μm.
The tip from ridge portion of the elastic member at the position of 20μm Martens hardness HM (load: 1000μN) is 1.5 N / mm ² or more 5.0 N / mm ² or less,
A cleaning blade that features that. The cleaning blade according to claim 1, wherein the area ratio of the domain in the cross section of the region is 0.5% or more and 30% or less. The cleaning blade according to any one of claims 1 to 2, wherein the domain has a polysiloxane structure derived from an NCO-terminated silicone prepolymer. A process cartridge having at least an image carrier and cleaning means for removing toner remaining on the image carrier.
A process cartridge, wherein the cleaning means has the cleaning blade according to any one of claims 1 to 3. An image carrier, a charging means for charging the surface of the image carrier, and
An exposure means that exposes the charged image carrier to form an electrostatic latent image,
A developing means for developing a visible image by developing the electrostatic latent image with toner, and
A transfer means for transferring the visible image to a recording medium,
A fixing means for fixing the transferred image transferred to the recording medium, and
An image forming apparatus comprising a cleaning means for removing toner remaining on the image carrier.
An image forming apparatus according to any one of claims 1 to 3, wherein the cleaning means has a cleaning blade.

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