JP2015158654A - Method of manufacturing cleaning blade, cleaning blade, image forming apparatus, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a cleaning blade configured to prevent cleaning failure which is caused due to a difference in hardness in a longitudinal direction of the blade, or a projection on a surface of the blade.SOLUTION: A method of manufacturing a cleaning blade having a strip-like elastic blade includes the steps of: (1) manufacturing an elastic blade preliminary body formed of polyurethane rubber; (2) impregnating at least an image-carrier contact section of the elastic blade preliminary body with a UV-curable composition including a (meth)acrylate compound; (3) immersing the impregnated portion of the elastic blade preliminary body in a cleaning solvent, to remove the UV-curable composition including the (meth)acrylate compound remaining on the surface; and (4) curing the UV-curable composition including the (meth)acrylate compound impregnated in the elastic blade preliminary body, to form the elastic blade.

Description

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

Conventionally, in an electrophotographic image forming apparatus, unnecessary transfer residual toner adhering to a surface after transferring a toner image to a transfer paper or an intermediate transfer member is cleaned on an image carrier such as a photosensitive member as a member to be cleaned. It is removed by means of a cleaning device.
As a cleaning member of this cleaning device, one that uses a strip-shaped elastic blade is well known because it can generally be simplified in configuration and has excellent cleaning performance. This elastic blade is made of an elastic body such as polyurethane rubber. Then, the base end of the elastic blade is supported by a support member, and the tip ridge line portion is pressed against the peripheral surface of the image carrier, and the toner remaining on the image carrier is damped and scraped off and removed.

  However, as shown in FIG. 6A, the elastic blade of polyurethane increases the frictional force between the image carrier 123 and the cleaning blade 62, and the cleaning blade 62 is pulled in the moving direction of the image carrier 123, so that the cleaning blade The leading edge ridge portion 62c of 62 is turned up. Further, if the cleaning is continued with the leading edge portion 62c of the cleaning blade 62 turned up, as shown in FIG. 6B, the cleaning blade 62 is separated from the leading edge portion 62c of the blade leading surface 62a by several [μm]. Local wear will occur at the spot. If the cleaning is further continued in such a state, the local wear increases, and the leading edge portion 62c is lost as shown in FIG. 6C. If the leading edge portion 62c is missing, the toner cannot be properly cleaned, resulting in poor cleaning.

  Therefore, in order to suppress the turning of the tip ridge line portion of the cleaning blade, it is necessary to make the tip ridge line portion hard and difficult to deform. As a technique for increasing the hardness of the tip, Patent Document 1 discloses a method of making the tip ridge line portion difficult to be deformed over time by making it impregnated with an ultraviolet curable resin so that the surface and the inside of the blade have high hardness.

  By the way, the method of impregnating and making the surface and the inside of the elastic blade high in hardness is impregnated with an ultraviolet curable resin from the surface of urethane rubber which is the base material of the elastic blade, and after the impregnation, excessively remains on the blade surface. After removing the resin, the resin is cured by ultraviolet irradiation. In this manufacturing method, the step of removing the resin remaining excessively on the blade surface is performed by wiping in the longitudinal direction of the blade using a solvent. However, not only the resin on the surface of the urethane rubber but also the resin impregnated inside is extracted. Since the extracted resin adheres to the non-woven fabric soaked with the solvent used for wiping, the concentration of the resin adhering to the non-woven fabric increases as the wiping progresses, and the resin extraction power decreases. As a result, the wiping force varies in the longitudinal direction of the blade, resulting in a gradient / unevenness in the amount of resin remaining inside the blade, and when it is finally cured, a large hardness gradient / unevenness appears. It was confirmed. If there is a hardness gradient / hardness unevenness in the longitudinal direction of the blade, since no uniform pressure is applied to the image carrier in the longitudinal direction, the toner partially slips, resulting in poor cleaning. In addition, if the contact time with the solvent used for wiping is long, the amount of the impregnated resin that is extracted increases, and even if the resin is cured, the tip ridge portion is curled without becoming high hardness. Slipping through and poor cleaning.

  Furthermore, as disclosed in Patent Documents 2 and 3, the cleaning blade produced through the impregnation and curing treatment has a convex portion on the surface of the cured layer unless the blade surface residue is uniformly removed after the impregnation treatment. When cleaning the toner remaining on the image carrier, the toner slips around the convex portion, resulting in poor cleaning. In Patent Document 2, after impregnating with an isocyanate compound, a process of wiping with excess solvent to blow off excess isocyanate compound by applying hot air and further wiping with a solvent is used. A sufficient treatment cannot be performed only with the treatment with hot air, and the wiping and removal with a solvent causes a hardness difference in the longitudinal direction of the blade as described above.

  The present invention has been made in view of the above background, and an object thereof is caused by a difference in hardness in the longitudinal direction of the elastic blade or a convex portion on the surface of the elastic blade in a method for manufacturing a cleaning blade having at least a strip-shaped elastic blade. It is an object of the present invention to provide a method for manufacturing a cleaning blade capable of solving a cleaning failure.

A method for manufacturing a cleaning blade according to the present invention includes:
A method of manufacturing a cleaning blade having at least a strip-shaped elastic blade,
(1) a step of producing an elastic blade preform made of polyurethane resin;
(2) impregnating an ultraviolet curable composition containing a (meth) acrylate compound into at least the image carrier contact portion of the elastic blade preform,
(3) a step of immersing the impregnated portion of the elastic blade preform in a cleaning solvent to remove the ultraviolet curable composition containing the (meth) acrylate compound remaining on the surface; and
(4) a step of curing the ultraviolet curable composition containing the (meth) acrylate compound impregnated in the elastic blade preform, to obtain a cleaning blade;
It is characterized by having.

  In the method for producing a cleaning blade according to the present invention, after the surface of the elastic blade preform is impregnated with the ultraviolet curable composition containing the (meth) acrylate compound, the excess remaining on the surface of the elastic blade preform. By removing the ultraviolet curable composition by immersing it in a cleaning solvent for a certain period of time, the ultraviolet curable composition can be removed uniformly in the longitudinal direction of the blade, thereby suppressing toner slippage. A cleaning defect can be solved.

FIG. 4A is an enlarged cross-sectional view of the cleaning blade, FIG. 4A is an explanatory diagram showing a state where the cleaning blade is in contact with the surface of the photosensitive member, and FIG. 1 is a schematic configuration diagram of a printer according to an embodiment of the present invention. 1 is a schematic configuration diagram of an image forming unit according to an embodiment of the present invention. The perspective view of the cleaning blade which concerns on this embodiment. The schematic diagram which showed the measurement location of the abrasion width | variety of an elastic blade. (A) is a diagram showing a state in which the leading edge portion of the cleaning blade is turned up, (b) is a diagram for explaining local wear on the leading end surface of the cleaning blade, and (c) is a diagram showing the leading edge portion of the cleaning blade. The figure which shows the state missing.

The method for manufacturing a cleaning blade of the present invention is a method for manufacturing a cleaning blade having at least a strip-shaped elastic blade, and includes the following steps.
(1) a step of producing an elastic blade preform made of polyurethane rubber;
(2) impregnating an ultraviolet curable composition containing a (meth) acrylate compound into at least the image carrier contact portion of the elastic blade preform,
(3) a step of immersing the impregnated portion of the elastic blade preform in a cleaning solvent to remove the ultraviolet curable composition containing the (meth) acrylate compound remaining on the surface; and
(4) A step of curing the ultraviolet curable composition containing the (meth) acrylate compound impregnated in the elastic blade preform to obtain an elastic blade.

  After the surface of the elastic blade preform is impregnated with the ultraviolet curable composition containing the (meth) acrylate compound, the excess ultraviolet curable composition remaining on the surface of the elastic blade preform is washed. By immersing and removing in a solvent for a certain period of time, the ultraviolet curable composition can be removed uniformly in the longitudinal direction of the elastic blade preform.

Since the cleaning solvent used in the present invention needs to dissolve the ultraviolet curable composition remaining on the surface of the elastic blade preform and remove it from the surface, the SP value of the cleaning solvent is that of a general acrylic resin. It is desirable that the value is close to 9.5 and the compatibility with the ultraviolet curable composition is high. Specifically, the SP value is preferably 8.0 or more and 11.5 or less.
In the present invention, the “solubility parameter value (SP) value” is a value defined by the regular solution theory introduced by Hildebrand, and is a measure of the solubility of the binary solution. Although there is a parameter value of itself, it is shown as a scale representing intermolecular force. Accordingly, those having a high SP value include polar compounds such as water, and those having a low SP value include hydrophobic compounds.

However, since the solvent capable of dissolving the ultraviolet curable composition also extracts the ultraviolet curable composition impregnated in the rubber, a cured layer on the surface may not be stably formed. There is a concern that variations may occur. Accordingly, the solvent used for cleaning is preferably a solvent having a high viscosity and hardly penetrates into the elastic blade preform, and preferably has a viscosity at 20 ° C. of 0.9 [mPa · s] or more. mPa · s] or less is more preferable.
The viscosity can be measured by an ordinary method. For example, it can be measured by using a viscometer manufactured by Brooklyn and using a spindle.

  In addition, the lower the vapor pressure of the solvent, the slower the impregnation rate into the urethane rubber, so that there is less penetration of the solvent into the elastic blade, and further restrains the resin from being extracted from the elastic blade preform. Is possible. For this reason, those having a lower vapor pressure are preferred. Specifically, the vapor pressure at 20 ° C. is preferably 15 [kPa] or less, more preferably 0.1 [kPa] or more.

  Further, the cleaning solvent contains a compound having a cyclic structure in the chemical structure, so that the penetration rate into the elastic blade preform is slower. Although the reason for this is not clear, it is considered that the ring structure is bulky as compared with the straight chain structure and the like, and the obstacle when entering the elastic blade preform is large. Therefore, as the cleaning solvent, a solvent having an annular structure, difficult to penetrate into the elastic blade preform, and difficult to extract the impregnated ultraviolet curable composition is preferable.

As a cleaning solvent, for example,
Cyclohexane: SP value 8.2, viscosity (20 ° C.) 0.98 mPa · s, vapor pressure (20 ° C.) 10.4 kPa
Cyclohexanone: SP value 9.9, viscosity (20 ° C.) 1.78 mPa · s, vapor pressure (20 ° C.) 0.5 kPa
1-methoxy-2-propanol: SP value 10.4, viscosity (20 ° C.) 1.81 mPa · s, vapor pressure (20 ° C.) 1 kPa
1-butanol: SP value 11.4, viscosity (20 ° C.) 3 mPa · s, vapor pressure (20 ° C.) 0.6 kPa
Methyl ethyl ketone: SP value 9.3, viscosity (20 ° C.) 0.4 mPa · s, vapor pressure (20 ° C.) 10.5 kPa
Toluene: SP value 8.9, viscosity (20 ° C.) 0.59 mPa · s, vapor pressure (20 ° C.) 3 kPa
Xylene: SP value 8.8, viscosity (20 ° C.) 0.81 mPa · s, vapor pressure (20 ° C.) 0.8 kPa
Butyl acetate: SP value 8.5, viscosity (20 ° C.) 0.74 mPa · s, vapor pressure (20 ° C.) 1.3 kPa
Tetrahydrofuran: SP value 9.1, viscosity (20 ° C.) 0.49 mPa · s, vapor pressure (20 ° C.) 20 kPa
Acetone: SP value 9.9, viscosity (20 ° C.) 0.32 mPa · s, vapor pressure (20 ° C.) 22 kPa
Ethanol: SP value 12.7, viscosity (20 ° C.) 1.2 mPa · s, vapor pressure (20 ° C.) 5.9 kPa
Diethyl ether: SP value 7.4, viscosity (20 ° C.) 0.24 mPa · s, vapor pressure (20 ° C.) 58.6 kPa
Ethylene glycol: SP value 14.2, viscosity (20 ° C.) 23.5 mPa · s, vapor pressure (20 ° C.) 0.07 kPa
Etc. can be preferably used. Cyclohexane and cyclohexanone are particularly preferable.
Only one cleaning solvent may be used, or two or more cleaning solvents may be mixed and used.

  In addition, a step of removing the residual solvent on the elastic blade preform after immersion in a cleaning solvent may be added. Examples of the removal method include air drying, a method of absorbing by a nonwoven fabric or sponge, a method of sliding a member such as rubber, metal, or glass on the elastic blade preform, scraping removal, etc. is not.

The cleaning blade of the present invention is a cleaning blade having at least a strip-shaped elastic blade, and the elastic blade has a (meth) acrylate compound at least on an image carrier contact portion of an elastic blade preform formed of polyurethane rubber. Martens hardness measured from the surface at a position 20 [μm] away from the tip ridge line portion of the elastic blade impregnated portion having a impregnated portion impregnated with the ultraviolet curable composition containing the ultraviolet curable composition The variation in the longitudinal direction is 35 [%] or less. There is no particular limitation on the Martens hardness on the surface of the impregnated portion of the elastic blade, but in order to prevent the toner from slipping through, the Martens hardness in the longitudinal direction measured from the surface at a position 20 μm away from the edge of the tip on the horizontal and vertical planes. Is required to be 35% or less, preferably 30% or less.
The impregnated portion of the elastic blade is a portion obtained by impregnating the elastic blade preform with an ultraviolet curable composition containing a (meth) acrylate compound and curing it.
About 5 points of the point where the side (tip ridge line part) that contacts the image carrier of the elastic blade is equally divided into 5 parts, 5 points each in the position 20 μm away from the tip ridge line part of the elastic blade impregnated part in the horizontal and vertical planes (total The Martens hardness was measured from the surface at 10 locations. In addition, the value of the variation in Martens hardness in the longitudinal direction was obtained by calculating the average of 5 points for each of the horizontal plane and the vertical plane, and determining the maximum percentage of variation from the average value.
The horizontal plane refers to the front end surface of the elastic blade including the front edge portion and facing the upstream surface in the traveling direction of the image carrier, and the vertical surface includes the front edge portion and facing the downstream surface in the traveling direction of the image carrier. Say the face.

FIG. 4 is a perspective view of the cleaning blade 62, and FIG. 5 is an enlarged cross-sectional view of the cleaning blade 62.
The cleaning blade 62 includes a strip-shaped holder 621 made of a rigid material such as metal or hard plastic, and a strip-shaped elastic blade 622.

The elastic blade 622 is fixed to one end side of the holder 621 with an adhesive or the like, and the other end side of the holder 621 is cantilevered by the case of the cleaning device 3.
The elastic blade 622 preferably has a high rebound resilience rate so that it can follow the eccentricity of the photosensitive member 2 and minute waviness on the surface of the photosensitive member.
In FIG. 4, 62a indicates the horizontal plane, and 62b indicates the vertical plane.

(Process for producing an elastic blade preform made of polyurethane rubber)
The elastic blade preform formed of the polyurethane rubber 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, and the polyurethane A prepolymer was added with a curing agent and, if necessary, a curing catalyst, cross-linked in a predetermined mold, and post-cross-linked in a furnace, formed into a sheet by centrifugal molding, allowed to stand at room temperature and aged It is manufactured by cutting a thing into a strip shape with a predetermined dimension.

There is no restriction | limiting in particular as said polyol compound, According to the objective, it can select suitably, For example, high molecular weight polyol, low molecular weight polyol, etc. are mentioned.
Examples of the high molecular weight polyol include a polyester polyol which is a condensate of an alkylene glycol and an aliphatic dibasic acid; ethylene adipate ester polyol, butylene adipate ester polyol, hexylene adipate ester polyol, ethylene propylene adipate ester polyol, ethylene butylene Polyester polyols such as polyester polyols of alkylene glycol and adipic acid such as adipate ester polyol and ethylene neopentylene adipate ester polyol; polycaprolactone polyols such as polycaprolactone ester polyol obtained by ring-opening polymerization of caprolactone; Polyethers such as oxytetramethylene) glycol and poly (oxypropylene) glycol Polyol, and the like. These may be used individually by 1 type and may use 2 or more types together.

  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′-diaminodiphenylmethane. Dihydric alcohols such as 4,4′-diaminodiphenylmethane; 1,1,1-trimethylolpropane, glycerin, 1,2,6-hexanetriol, 1,2,4-butanetriol, trimethylolethane, Examples thereof include trivalent or higher polyhydric alcohols such as 1,1,1-tris (hydroxyethoxymethyl) propane, diglycerin, and pentaerythritol. These may be used individually by 1 type and may use 2 or more types together.

There is no restriction | limiting in particular as said polyisocyanate compound, According to the objective, it can select suitably, For example, a methylene diphenyl diisocyanate (MDI), tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), naphthylene 1,5 Diisocyanate (NDI), tetramethylxylene diisocyanate (TMXDI), isophorone diisocyanate (IPDI), hydrogenated xylylene diisocyanate (H ₆ XDI), dicyclohexylmethane diisocyanate (H ₁₂ MDI), hexamethylene diisocyanate (HDI), dimer acid diisocyanate (DDI), norbornene diisocyanate (NBDI), trimethylhexamethylene diisocyanate (TMDI), and the like. These may be used individually by 1 type and may use 2 or more types together.

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 to 0.5% by mass, and 0.05% by mass to 0.3% by mass. Is more preferable.

  The elastic blade preform can also be a two-layer type in which two different materials are laminated.

FIG. 1 is an enlarged cross-sectional view of the cleaning blade 62. FIG. 1A is an explanatory view showing a state in which the cleaning blade 62 is in contact with the surface of the photosensitive member 2, and FIG. 1B is an enlarged explanatory view in the vicinity of the tip ridge line portion 62 c of the cleaning blade 62. .
The elastic blade 622 is obtained by impregnating at least the image carrier abutting portion of the elastic blade preform with an ultraviolet curable composition containing a (meth) acrylate compound. An impregnation process, which will be described in detail later, is performed on a certain tip ridge line portion 62c.

  As the hardness of the elastic blade preform of the elastic blade 622, the tan δ peak temperature of the rubber measured with a DMS6100 manufactured by SII or the like is 0 [° C.] or higher, and each hardness at 23 [° C.] and 10 [° C.] ( Urethane rubber having a difference of JIS-A) of 5 degrees or more is preferable.

(Step of impregnating at least the image carrier contact portion of the elastic blade preform with an ultraviolet curable composition containing a (meth) acrylate compound)
The image carrier contact portion of the elastic blade preform is preferably the tip ridge portion of the elastic blade, and the elastic blade is UV-cured containing a (meth) acrylate compound so that the tip ridge portion is impregnated. Impregnate the composition.
The impregnation treatment of the tip edge line portion 62c of the elastic blade 622 can be impregnated with an ultraviolet curable composition containing a (meth) acrylate compound by brush coating, spray coating, dip coating, or the like.
The impregnation treatment may be performed by impregnating the tip ridge line portion, but it is preferable to impregnate the tip ridge line portion to a position separated by 0.5 mm or more from the horizontal plane and the vertical plane. In FIG. 1B, the lower end including the tip ridge line portion 62c of the elastic blade 622 is impregnated. However, the present invention is not limited to this, and the horizontal plane 62a and the vertical surface 62b are each separated by 0.5 mm or more from the tip ridge line portion 62c. It only needs to be impregnated. It is more preferable that the range of 0.5 mm or more and 1 cm or less from the tip ridge is impregnated. If the impregnation range exceeds 1 cm, elasticity may be impaired.
The impregnation time is preferably 5 to 60 minutes, and the temperature during the impregnation is preferably 10 to 35 ° C.

The (meth) acrylate compound having a molecular weight of 100 to 1,500 can be used.
The (meth) acrylate compound having a molecular weight of 100 to 1,500 is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include dipentaerythritol hexa (meth) acrylate and pentaerythritol tetra (meth). Acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol ethoxytetra (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, 1,6-hexanediol di (meth) acrylate, Ethoxylated bisphenol A di (meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,5-pentanediol di ( Acrylate), 1,6-hexanediol di (meth) acrylate, 1,7-heptanediol di (meth) acrylate, 1,8-octanediol di (meth) acrylate, 1,9-nonanediol di (meth) Acrylate, 1,10-decanediol di (meth) acrylate, 1,11-undecanediol di (meth) acrylate, 1,18-octadecanediol di (meth) acrylate, glycerin propoxytri (meth) acrylate, dipropylene glycol di (Meth) acrylate, tripropylene glycol di (meth) acrylate, PO-modified neopentyl glycol di (meth) acrylate, PEG600 di (meth) acrylate, PEG400 di (meth) acrylate, PEG200 di (meth) acrylate, Opentyl glycol hydroxypivalate ester di (meth) acrylate, octyl / decyl (meth) acrylate, isobornyl (meth) acrylate, ethoxylated phenyl (meth) acrylate, 9,9-bis [4- (2- (meth) acryloyl) Oxyethoxy) phenyl] fluorene, and the like. These may be used individually by 1 type and may use 2 or more types together. Among these, a compound having a pentaerythritol triacrylate structure having 3 to 6 functional groups is preferable.
Examples of the compound having a pentaerythritol triacrylate structure having 3 to 6 functional groups include pentaerythritol triacrylate and dipentaerythritol hexaacrylate.

  Furthermore, as described in Japanese Patent Application No. 2012-282844, it is possible to make the tip harder by mixing high hardness and high elasticity tricyclodecane or acrylate or methacrylate having an adamantane skeleton. Even if there are few functional groups, the lack of crosslinking points can be compensated for by the special structure of tricyclodecane or adamantane skeleton, so that even when impregnated inside the elastic body, high hardness and high elasticity can be achieved. By making the hardness high, deformation of the tip of the cleaning blade can be prevented, and by being highly elastic, followability to the photoreceptor can be maintained. Examples of the acrylate or methacrylate having a tricyclodecane or adamantane skeleton include tricyclodecane dimethanol diacrylate, 1,3-adamantane dimethanol diacrylate, 1,3-adamantane dimethanol dimethacrylate, 1,3,5-adamantanetri There are methanol triacrylate, 1,3,5-adamantane trimethanol trimethacrylate, etc., and two or more of these may be used in combination.

  In addition, the number of functional groups of the acrylate or methacrylate having a tricyclodecane or adamantane skeleton is preferably 1 to 6, and more preferably 2 to 4. Since only one functional group has a weak cross-linking structure, and five or more functional groups may cause steric hindrance, it is preferable to mix acrylates or methacrylates having different numbers of functional groups.

  There is no restriction | limiting in particular as another component, According to the objective, it can select suitably, For example, a photoinitiator, a polymerization inhibitor, a diluent, etc. are mentioned.

  The photopolymerization initiator is not particularly limited as long as it generates active species such as radicals and cations by the energy of light and initiates polymerization, and can be appropriately selected according to the purpose. A polymerization initiator, a photocationic polymerization initiator, etc. are mentioned. Among these, a photo radical polymerization initiator is particularly preferable.

  Examples of the radical photopolymerization initiator include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazoles, and the like. Examples thereof include compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon halogen bond, and alkylamine compounds.

  The radical photopolymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose. For example, acetophenone, acetophenone benzyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone , Xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, Michler's ketone, benzoin propyl ether , Benzoin ethyl ether, benzyldimethyl ketal, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1 Phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, bis (2 , 4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 2,4-diethylthioxanthone, bis- (2,6-dimethoxybenzoyl) -2,4 , 4-trimethylpentylphosphine oxide, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Commercially available products can be used as the photoradical polymerization initiator. Examples of the commercially available products include Irgacure 651, Irgacure 184, DAROCUR 1173, Irgacure 2959, Irgacure 127, Irgacure 907, Irgacure 369, Irgacure 379, DAROCUR TPO. IRGACURE 819, IRGACURE 784, IRGACURE OXE 01, IRGACURE OXE 02, IRGACURE 754 (above, manufactured by Ciba Specialty Chemicals); Speedcure TPO (manufactured by Lambson); KAYACURE DETX-S (manufactured by Nippon Kayaku Co., Ltd.) Lucirin TPO, LR8883, LR8970 (above, manufactured by BASF); Ubekrill P36 (manufactured by UCB), and the like. These may be used individually by 1 type and may use 2 or more types together.

  The content of the photopolymerization initiator is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1% by mass to 20% by mass with respect to the ultraviolet curable composition.

  The polymerization inhibitor is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include p-methoxyphenol, cresol, t-butylcatechol, di-t-butylparacresol, hydroquinone monomethyl ether, α- Naphthol, 3,5-di-tert-butyl-4-hydroxytoluene, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-butylphenol) Phenol compounds such as 4,4′-thiobis (3-methyl-6-t-butylphenol); p-benzoquinone, anthraquinone, naphthoquinone, phenanthraquinone, p-xyloquinone, p-toluquinone, 2,6-dichloroquinone 2,5-diphenyl-p-benzoquinone, 2,5-diacetoxy-p-benzox 2,5-dicaproxy-p-benzoquinone, 2,5-diacyloxy-p-benzoquinone, hydroquinone, 2,5-di-butylhydroquinone, mono-t-butylhydroquinone, monomethylhydroquinone, 2,5-di-t A quinone compound such as amylhydroquinone; an amine compound such as phenyl-β-naphthylamine, p-benzylaminophenol, di-β-naphthylparaphenylenediamine, dibenzylhydroxylamine, phenylhydroxylamine, diethylhydroxylamine; Nitro compounds such as nitrotoluene and picric acid; oxime compounds such as quinone dioxime and cyclohexanone oxime; and sulfur compounds such as phenothiazine. These may be used individually by 1 type and may use 2 or more types together.

  As the diluent, it is desirable that the ultraviolet curable resin is soluble and has a low boiling point. In particular, the boiling point is preferably 160 ° C. or lower, more preferably 100 ° C. or lower. Diluting solvents that can be used include hydrocarbon solvents such as toluene and xylene, ester solvents such as ethyl acetate, n-butyl acetate, methyl cellosolve acetate and propylene glycol monomethyl ether acetate, or methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone. , Ketones such as cyclopentanone and acetone, or ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether and propylene glycol monomethyl ether, or alcohols such as ethanol, propanol, 1-butanol, isopropyl alcohol and isobutyl alcohol Other organic solvents can also be used. These may be used individually by 1 type and may use 2 or more types together.

(Step of removing the ultraviolet curable composition containing the (meth) acrylate compound remaining on the surface by immersing the impregnated portion of the elastic blade preform in a cleaning solvent)
Next, the impregnated portion of the elastic blade preform in which the image bearing member contact portion is impregnated with an ultraviolet curable composition containing a (meth) acrylate compound is immersed in the cleaning solvent and remains on the surface. Remove the UV curable composition.
It is preferable to immerse at least the region of the cleaning solvent impregnated with the ultraviolet curable composition at a temperature not higher than the boiling point of the cleaning solvent. The immersion treatment is more preferably performed at a temperature of 10 to 30 ° C. Further, the treatment time cannot be generally specified because the cleaning ability varies depending on the solvent type, but it is preferably 1 second or more and 1 minute or less, more preferably 30 seconds or less, and particularly preferably 20 seconds or less. In order to remove the residue remaining on the surface, it is preferable to contact with the solvent for 1 second or longer, and in order to reduce the extraction amount of the impregnated resin, 1 minute or shorter is preferable. This is because if the immersion time is long, the resin impregnated in the vicinity of the surface of the impregnated portion is extracted even if the solvent penetrates slowly into the blade. When the extraction amount of the impregnated resin is increased, the tip ridge line portion is curled without increasing the hardness even if the resin is cured.

(Step of curing the ultraviolet curable composition containing the (meth) acrylate compound impregnated in the elastic blade preform to form a cleaning blade)
The irradiation condition of ultraviolet rays used for curing the ultraviolet curable cured product is not particularly limited and can be appropriately selected according to the purpose, but the integrated light quantity is 500 mJ / cm ^{2 to} 5,000 mJ / cm. ² is preferred.

Hereinafter, an embodiment in which the present invention is applied to an electrophotographic printer (hereinafter simply referred to as a printer) as an image forming apparatus will be described.
The image forming apparatus of the present invention includes an image carrier, a charging unit for charging the surface of the image carrier, a latent image forming unit for forming an electrostatic latent image on the charged surface of the image carrier, and the image carrier. A developing means for developing the electrostatic latent image formed on the surface into a toner image, a transfer means for transferring the toner image on the surface of the image carrier to a transfer body, and abutting on the surface of the image carrier; In the image forming apparatus provided with a cleaning unit having a cleaning blade for cleaning the transfer residual toner adhering to the surface of the image carrier, the cleaning blade of the present invention is used as the cleaning blade.
FIG. 2 is an overall configuration diagram showing an outline of the image forming apparatus of the present invention. The main part of the image forming apparatus will be described below with reference to FIG.

  The image forming apparatus includes four process units 1K, 1C, 1M, and 1Y each having an image forming unit for forming an image with developers of different colors of black, cyan, magenta, and yellow corresponding to color separation components of a color image. It has. The process units 1K, 1C, 1M, and 1Y have the same configuration except that they store different color toners. The configuration of the process unit 1K will be described by taking the process unit 1K as an example. The process unit 1K includes an image carrier (photosensitive member) 2, a cleaning unit 3, a charging unit 4, a developing unit 5, a toner storage unit 6, and the like. ing. The process unit 1K is detachably attached to the main body of the image forming apparatus. As shown in FIG. 2, an exposure unit 7 is disposed above the process units 1K, 1C, 1M, and 1Y. The exposure device 7 is configured to emit laser beams (L1 to L4) from a laser diode based on image data.

  A transfer belt device 8 is disposed below each process unit 1K, 1C, 1M, 1Y. The transfer belt device 8 includes an intermediate transfer belt 12 for transferring a toner image formed by the image carrier 2. The intermediate transfer belt 12 is configured to be spanned between four primary transfer rollers 9 a, 9 b, 9 c, 9 d facing each image carrier 2, a driving roller 10, a tension roller 11, and a cleaning backup roller 15 and rotationally driven. ing. A secondary transfer roller 13 is disposed facing the driving roller 10, and a belt cleaning device 14 is disposed facing the cleaning backup roller 15.

  At the bottom of the image forming apparatus, a paper feed cassette 16 that can store a large number of sheets and a paper feed roller 17 that feeds the sheets from the paper feed cassette 16 are provided. On the way from the paper feed roller 17 to the nip between the secondary transfer roller 13 and the driving roller 10, a registration roller pair 18 for temporarily stopping the paper is provided.

  Above the nip between the secondary transfer roller 13 and the driving roller 10, a fixing device 19 having a fixing roller 25, a pressure roller 26, and the like is provided. Above the fixing device 19, a pair of paper discharge rollers 20 for discharging the paper to the outside is disposed. The paper discharged by the paper discharge roller pair 20 is configured to be stacked on a paper discharge tray 21 formed by recessing the upper surface of the image forming apparatus main body inward.

  Between the transfer belt device 8 and the paper feed cassette 16, a waste toner container 22 for storing waste toner is disposed. A waste toner transfer hose (not shown) extending from the belt cleaning device 14 is connected to the entrance of the waste toner container 22.

  FIG. 3 is a schematic configuration diagram showing a state in which the process unit 1K is removed from the image forming apparatus main body or before being mounted. As shown in FIG. 3, the process unit has a housing 23. The casing 23 is formed by resin injection molding. As this resin, for example, a polycarbonate resin, a tolyl butadiene styrene resin for acrylic, a tolyl styrene resin for acrylic, a styrene resin, a polyphenylene ether resin, a polyphenylene oxide resin, a polyether terephthalate resin, or an alloy resin thereof is applied. Can do. In the housing 23, the image carrier 2, the cleaning unit 3, the charging unit 4, the developing unit 5 and the like are arranged. The cleaning means has the cleaning blade of the present invention.

Next, an image forming operation in the printer will be described.
When a print execution signal is received from an operation unit (not shown) or the like, a predetermined voltage or current is sequentially applied to the charging device 4 and the developing roller 5 as charging means at predetermined timing. Similarly, a predetermined voltage or current is sequentially applied to the exposure apparatus and the charge removal lamp at predetermined timing. In synchronism with this, the photosensitive member 2 is rotationally driven in the direction of the arrow in the figure by a photosensitive member driving motor (not shown) as driving means.

  When the photoconductor 2 rotates in the direction of the arrow in the figure, the surface of the photoconductor is first charged to a predetermined potential by the charging device 4. Then, light L corresponding to the image signal is irradiated onto the photoconductor 2 from an exposure device (not shown), and the portion of the photoconductor 2 irradiated with the light L is neutralized to form an electrostatic latent image.

  The photosensitive member 2 on which the electrostatic latent image is formed is rubbed against the surface of the photosensitive member 2 with a magnetic brush of developer formed on the developing roller at a portion facing the developing device 5 as developing means. At this time, the negatively charged toner on the developing roller moves to the electrostatic latent image side by a predetermined developing bias applied to the developing roller and is converted into a toner image (development). As described above, in this embodiment, the electrostatic latent image formed on the photoreceptor 2 is reversely developed by the developing device 5 with the negatively charged toner. In this embodiment, an example using a non-contact charging roller system 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 image formed on the photosensitive member 2 is formed between the photosensitive member 2 and the transfer device 12 as a transfer unit through a paper feeding unit (not shown) through an opposing portion of the upper registration roller and the lower registration roller. The image is transferred to a transfer sheet fed to the transfer area. At this time, the transfer paper is supplied in synchronism with the leading edge of the image at the facing portion between the upper registration roller and the lower registration roller. In addition, a predetermined transfer bias is applied during transfer onto the transfer paper. The transfer paper onto which the toner image has been transferred is separated from the photoreceptor 2 and conveyed to a fixing device (not shown) as fixing means. By passing through the fixing device, the toner image is fixed on the transfer paper by the action of heat and pressure, and the transfer paper is discharged out of the apparatus.
On the other hand, the residual toner after the transfer is removed from the surface of the photoreceptor 2 after the transfer by a cleaning device 3 as a cleaning means, and the charge is removed by a charge removal lamp.

  In this printer, the image carrier and a cleaning unit having at least a cleaning blade for removing transfer residual toner attached to the surface of the image carrier are integrally supported, and are detachable from the image forming apparatus main body. It can be a process cartridge. In FIG. 3, an image carrier (photoconductor) 2 and a cleaning device 3, a charging device 4, a developing device 5 and the like as process means are housed in a housing 23, and can be integrally attached to and detached from the apparatus main body as a process cartridge. It has become. In this embodiment, the photosensitive member 2 as a process cartridge and the process means are integrally replaced. However, units such as the photosensitive member 2, the cleaning device 3, the charging device 4, and the developing device 5 are used. It is also possible to replace it with a new one.

Further, the present invention relates to the following manufacturing method of the cleaning blade [1], and includes the following [2] to [8] as embodiments.
[1] A method for manufacturing a cleaning blade having at least a strip-shaped elastic blade, the method including the following steps:
(1) a step of producing an elastic blade preform made of polyurethane rubber;
(2) impregnating an ultraviolet curable composition containing a (meth) acrylate compound into at least the image carrier contact portion of the elastic blade preform,
(3) a step of immersing the impregnated portion of the elastic blade preform in a cleaning solvent to remove the ultraviolet curable composition containing the (meth) acrylate compound remaining on the surface; and
(4) A step of curing the ultraviolet curable composition containing the (meth) acrylate compound impregnated in the elastic blade preform to obtain an elastic blade.
[2] The method for producing a cleaning blade according to [1], wherein the SP value of the cleaning solvent used in the step (3) is 8.0 or more and 11.5 or less.
[3] The cleaning blade according to [1] or [2], wherein the cleaning solvent used in the step (3) has a viscosity at 20 ° C. of 0.9 [mPa · s] or more. Production method.
[4] The cleaning blade according to any one of [1] to [3], wherein the cleaning solvent used in the step (3) has a vapor pressure at 20 ° C. of 15 [kPa] or less. Production method.
[5] The method for producing a cleaning blade according to any one of [1] to [4], wherein the cleaning solvent used in the step (3) contains a compound having a cyclic structure.
[6] In any one of the above [1] to [5], in the step (3), the immersion time for immersing the impregnated portion of the elastic blade preform in the cleaning solvent is within 20 seconds. The manufacturing method of the cleaning blade of description.
[7] A cleaning blade having at least a strip-shaped elastic blade, wherein the elastic blade includes an ultraviolet curable compound containing a (meth) acrylate compound at least on an image carrier contact portion of an elastic blade preform formed of polyurethane rubber. In the longitudinal direction of the Martens hardness measured from the surface at a position 20 [μm] away from the tip ridge line portion in a plane perpendicular to the horizontal plane of the elastic blade impregnated portion, impregnated with the composition and UV-cured. The cleaning blade has a variation of 35% or less.
[8] an image carrier;
Charging means for charging the surface of the image carrier;
Latent image forming means for forming an electrostatic latent image on the surface of the charged image carrier;
Developing means for developing the electrostatic latent image formed on the surface of the image bearing member into a toner image;
Transfer means for transferring the toner image on the surface of the image carrier to a transfer body;
In an image forming apparatus provided with a cleaning unit having a cleaning blade that contacts the surface of the image carrier and cleans transfer residual toner attached to the surface of the image carrier.
An image forming apparatus using the cleaning blade according to [7] as the cleaning blade.
[9] In a process cartridge that integrally supports an image carrier and a cleaning unit having a cleaning blade that removes at least the transfer residual toner attached to the surface of the image carrier, and is detachable from the image forming apparatus main body. A process cartridge using the cleaning blade according to [7] as the cleaning blade.

  Next, the present invention will be described in more detail with reference to examples performed by the present applicants, but the present invention is not limited to these examples.

Examples 1-14, Comparative Examples 1-4
[Elastic blade preform]
With reference to the method for producing a single-layer cleaning blade described as a reference example in JP 2011-141449 A, 48.56 parts by mass of p-MDI, PCL210N (polycaprolactone diol having a linear glycol as an initiator, (Number average molecular weight 1000; Daicel Chemical Industries) 51.44 parts by mass of a prepolymer was prepared in advance, this prepolymer, PCL210N40.82 parts by mass, 3.34 parts by mass of trimethylolpropane as a crosslinking agent, and chain extension A polyurethane stock solution was prepared by mixing 5.22 parts by mass of 1,4-butanediol as an agent. This polyurethane stock solution was made into a strip-shaped elastic blade preform with an average thickness of 1.8 mm, 11.5 mm × 32.6 cm by centrifugal molding.
The obtained elastic blade preform had a JIS-A hardness of 68 degrees and a rebound resilience of 30%.

The hardness of the elastic blade preform was measured according to JIS K6253 using a micro rubber hardness meter MD-1 manufactured by Kobunshi Keiki Co., Ltd.
The rebound resilience of the elastic blade preform is No. manufactured by Toyo Seiki Seisakusho. The measurement was performed according to JIS K6255 using a 221 regilynester. The sample was a stack of about 2 [mm] sheets so that the thickness was 4 [mm] or more.

[Impregnating material]
As the curable composition used for the impregnation treatment, the following curable materials 1 to 3 were used.
<Curing material 1>
UV curable resin: tricyclodecane dimethanol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: A-DCP, functional group number 2, molecular weight 304)
80 parts Polymerization initiator: Ciba Specialty Chemicals Irgacure 184 5 parts Solvent: Cyclohexanone 15 parts

<Curing material 2>
UV curable resin: 1,3-adamantane dimethanol diacrylate (manufactured by Idemitsu Kosan Co., Ltd., X-A-201, functional group number 2, molecular weight 304) 50 parts Polymerization initiator: Ciba Specialty Chemicals Co., Ltd. Irgacure 184 5 parts Solvent: 45 parts of cyclohexanone

<Curing material 3>
UV curable resin: pentaerythritol triacrylate (manufactured by Daicel Cytec, PETIA, functional group number 3, molecular weight 298) 50 parts Polymerization initiator: Ciba Specialty Chemicals Irgacure 184 5 parts Solvent: cyclohexanone 45 parts

The leading edge ridge line portion that becomes the image carrier contact portion of the elastic blade preform was impregnated with a curable material shown in Table 2. As shown in FIG. 1B, the impregnation range was the lower end including the tip ridge line portion of the elastic blade, and the lower end was immersed in a curable material at a depth of 2 mm and impregnated. The impregnation time was 20 minutes and the temperature was 24 ° C.
As a residue removal step after the impregnation treatment, immersion in a solvent was carried out in Examples 1 to 14, wiped off with a solvent in Comparative Examples 1 to 3, and dry wiping without using a solvent in Comparative Example 4.

[Cleaning solvent]
As the cleaning solvents of Examples 1 to 14, the following solvents 1 to 13 were used, and the impregnated blade was immersed at 24 ° C. The immersion time was 20 seconds in Examples 1 to 13 and 1 minute in Example 14.
<Solvent 1>
Cyclohexane (Kanto Chemical)
The structure is shown in [Chemical Formula 1].

<Solvent 2>
Cyclohexanone (manufactured by Kanto Chemical)
The structure is shown in [Chemical 2].

<Solvent 3>
1-methoxy-2-propanol (manufactured by Kanto Chemical)
The structure is shown in [Chemical Formula 3].

<Solvent 4>
1-butanol (manufactured by Kanto Chemical)
The structure is shown in [Chemical Formula 4].

<Solvent 5>
Methyl ethyl ketone (manufactured by Kanto Chemical)
The structure is shown in [Chemical 5].

<Solvent 6>
Toluene (Kanto Chemical)
The structure is shown in [Chemical 6].

<Solvent 7>
Xylene (manufactured by Kanto Chemical)
The structure is shown in [Chemical 7]. (Xylene uses a mixture of ortho, meta, and para forms; [Chemical Formula 7] represents an ortho form.)

<Solvent 8>
Butyl acetate (manufactured by Kanto Chemical)
The structure is shown in [Chemical 8].

<Solvent 9>
Tetrahydrofuran (Kanto Chemical)
The structure is shown in [Chemical 9].

<Solvent 10>
Acetone (manufactured by Kanto Chemical)
The structure is shown in [Chemical Formula 10].

<Solvent 11>
Ethanol (manufactured by Kanto Chemical)
The structure is shown in [Chemical 11].

<Solvent 12>
The diethyl ether structure is shown in [Chemical Formula 12].

<Solvent 13>
The ethylene glycol structure is shown in [Chemical 13].

[Wipe solvent]
As solvents for wiping in Comparative Examples 1 to 3, the following solvents 1 to 3 were used, soaked in Bencott (manufactured by Asahi Kasei Co., Ltd.), and the residue on the impregnated portion of the blade was wiped off.
<Solvent 1>
Methyl ethyl ketone (manufactured by Kanto Chemical)
The structure is as described in [Chemical 5] above.
<Solvent 2>
Toluene (Kanto Chemical)
The structure is as described in [Chemical Formula 6] above.
<Solvent 3>
Ethanol (manufactured by Kanto Chemical)
The structure is as described in [Chemical 11] above.

Table 1 shows the characteristic values of each solvent. (The vapor pressure indicates the MSDS value of Kanto Chemical Co., Inc.)

The crosslinked structure by each hardening material was formed by the above-mentioned dipping coating method. In Examples 1 to 14, the dipping step is specifically performed by impregnating the elastic blade preform with the hardened materials 1 to 3 at 24 ° C. for 20 minutes, and then in the cleaning solvent at 24 ° C. for 20 minutes. Immersion cleaning was performed for seconds (Examples 1 to 13) or for 1 minute (Example 14). After washing, the solvent remaining on the surface was wiped off with a sponge, and ultraviolet exposure (140 [W / cm] × 5 [m / min] × 5 passes) was performed. Furthermore, it dried for 15 minutes at the internal temperature of 100 degreeC using the heat dryer.
In Comparative Examples 1 to 3, the cured materials 1 and 2 were impregnated at 24 ° C. for 20 minutes, and then a solvent for wiping was impregnated into Bencott (manufactured by Asahi Kasei Co., Ltd.). Wiping in the direction and ultraviolet exposure (140 [W / cm] × 5 [m / min] × 5 passes) were performed. Furthermore, it dried for 15 minutes at the internal temperature of 100 degreeC using the heat dryer.
In Comparative Example 4, the cured material 2 was used for impregnation at 24 ° C. for 20 minutes, and then the residue of the impregnated portion of the blade was dry-wiped in the longitudinal direction of the blade with Bencott (manufactured by Asahi Kasei Co., Ltd.), and ultraviolet exposure (140 [W / Cm] × 5 [m / min] × 5 passes). Furthermore, it dried for 15 minutes at the internal temperature of 100 degreeC using the heat dryer.

The dispersion in the longitudinal direction of the Martens hardness measured from the surface of the impregnated portion of the obtained elastic blade at a position 20 [μm] away from the tip ridge line portion on the horizontal plane and the vertical plane was measured as follows.
Specifically, the five points of the edge (tip ridge line part) that contacts the image carrier of the elastic blade are equally divided into five parts at a position 20 μm away from the tip ridge line part of the elastic blade impregnated part in a plane perpendicular to the horizontal plane. Martens hardness was measured from the surface at each of 5 locations (10 locations in total). In addition, the value of the variation in Martens hardness in the longitudinal direction was obtained by calculating the average of 5 points for each of the horizontal plane and the vertical plane, and determining the maximum percentage of variation from the average value.
The results are shown in Table 2. The hardness variation shown in Table 2 indicates the larger of the maximum variations in the horizontal plane and the vertical plane.
Hardness measurement:
Using a FISCHERSCOPE HM2000, a microhardness tester manufactured by FISCHER, measured from the surface of each blade at an indentation load of 2 mN and an indentation time of 10 s at a location 20 μm from the edge of the tip.

Presence of blade surface residue:
Observation was made using a KEYENCE microscope VHX-100, and the presence or absence of a residue that seemed to be a residue of the coating liquid on the blade surface was confirmed, and the following determination was made.
None: Flat state with no residue at the tip ridge line Low: Residue remains at a part of the tip ridge line Many: Residue remains at the entire area of the tip ridge line

Next, the configuration of the image forming apparatus in which the embodiment is performed will be described.
The obtained elastic blade was fixed with an adhesive to a sheet metal holder that can be mounted on the Ricoh color composite machine imgio MP C5001 to obtain a prototype cleaning blade. This was similarly attached to a Ricoh color composite machine imagio MP C5001 (same configuration as FIG. 2), and image forming apparatuses of Examples 1 to 14 and Comparative Examples 1 to 4 were produced. The cleaning blade was attached with a linear pressure and a cleaning angle set according to a predetermined tip biting amount and attachment angle. Also, the lubricant application device was removed.

For the evaluation, a toner prepared by a polymerization method was used. The physical properties of the toner are as follows.
Toner base: circularity 0.98, average particle size 4.9 [μm]
External additive: 1.5 parts of small particle size silica (Clariant H2000)
0.5 parts small particle size titanium oxide (Taika MT-150AI)
1.0 parts of large particle size silica (UFP-30H manufactured by Denki Kagaku Kogyo)

The evaluation was performed in a laboratory environment: 21 [° C.] · 65 [% RH], paper feeding condition: image area ratio 5% chart at 3 prints / job at 10,000 sheets (A4 landscape).
[Evaluation item]
Image at the time of evaluation: Vertical band pattern (with respect to the paper traveling direction) 43 [mm] width, 3 charts
Output 20 sheets (A4 side)
Toner slipping evaluation:
The surface of the photoreceptor immediately after the cleaning blade was transferred with a tape, and the presence or absence of toner or the like was confirmed, and the following determination was made. The evaluation was performed when 20 images were output initially (after 10 images were output) and when 20 images were output after 10,000 outputs.
○: Initial evaluation, no slipping out after 10,000 sheets output △: No slipping out in the initial evaluation stage, but slipping out after 10,000 sheets output ×: Initial slipping out

Bad cleaning on image:
After outputting 10,000 sheets, the output image after outputting 20 images at the time of evaluation of the vertical band pattern (with respect to the paper traveling direction) 43 mm wide and 3 charts (A4 size landscape) was visually observed. The cleaning properties were evaluated according to the following criteria. Note that an abnormal image means an image or white spot image that appears in a streak or strip shape in a printed image.
○: No abnormal image ×: There is an abnormal image

Table 2 shows the evaluation results of Examples and Comparative Examples.

  From the results shown in Table 2, in the present invention, the surface residue removing step after impregnating the ultraviolet curable composition into the image carrier contact portion of the elastic blade preform is immersed in a cleaning solvent instead of wiping with a solvent. It was confirmed that the hardness variation in the longitudinal direction of the blade was greatly reduced. It was also confirmed that when the SP value of the cleaning solvent was 8.0 or more and 11.5 or less, the compatibility with the (meth) acrylate compound was good and the surface could be cleaned without residue. Furthermore, by using a solvent having a viscosity at 20 ° C. of 0.9 [mPa · s] or more, a vapor pressure of 15 [kPa] or less and a cyclic structure, extraction of the impregnated ultraviolet curable composition is suppressed. As a result, it became clear that the variation in hardness was further reduced. If the immersion time for washing is 1 minute, the hardness decreases, so that it is considered that toner slips slightly, but if it is 20 seconds, high hardness and hardness variation can be suppressed.

1K process unit (black)
1C process unit (cyan)
1M process unit (magenta)
1Y process unit (yellow)
2 Image carrier (photoreceptor)
3 Cleaning means 4 Charging means 5 Developing means (developing roller)
6 toner storage unit 7 exposure device 8 transfer belt device 9 primary transfer roller 10 drive roller 11 tension roller 12 intermediate transfer belt 13 secondary transfer roller 14 belt cleaning device 15 cleaning backup roller 16 paper feed cassette 17 paper feed roller 18 registration roller pair DESCRIPTION OF SYMBOLS 19 Fixing device 20 Paper discharge roller pair 21 Paper discharge tray 22 Waste toner container 23 Case 25 Fixing roller 26 Pressure roller 62 Cleaning blade 62a Cleaning blade front end surface (horizontal plane)
62b Vertical surface of the cleaning blade tip ridge line portion 62c Cleaning blade tip ridge line portion 123 Image carrier 621 Holder 622 Elastic blade

Japanese Patent Application No. 2012-282844 JP 2004-280086 A JP 2007-52062 A

Claims (9)

A method for manufacturing a cleaning blade having at least a strip-shaped elastic blade, the method including the following steps:
(1) a step of producing an elastic blade preform made of polyurethane rubber;
(2) impregnating an ultraviolet curable composition containing a (meth) acrylate compound into at least the image carrier contact portion of the elastic blade preform,
(3) a step of immersing the impregnated portion of the elastic blade preform in a cleaning solvent to remove the ultraviolet curable composition containing the (meth) acrylate compound remaining on the surface; and
(4) A step of curing the ultraviolet curable composition containing the (meth) acrylate compound impregnated in the elastic blade preform to obtain an elastic blade.   The cleaning blade manufacturing method according to claim 1, wherein the cleaning solvent used in the step (3) has an SP value of 8.0 or more and 11.5 or less.   The method for producing a cleaning blade according to claim 1 or 2, wherein a viscosity of the cleaning solvent used in the step (3) at 20 ° C is 0.9 [mPa · s] or more.   The method for producing a cleaning blade according to any one of claims 1 to 3, wherein the cleaning solvent used in the step (3) has a vapor pressure at 20 ° C of 15 [kPa] or less.   The method for manufacturing a cleaning blade according to any one of claims 1 to 4, wherein the cleaning solvent used in the step (3) contains a compound having a cyclic structure.   6. The cleaning blade according to claim 1, wherein in the step (3), the immersion time for immersing the impregnated portion of the elastic blade preform in a cleaning solvent is within 20 seconds. Method.   A cleaning blade having at least a strip-shaped elastic blade, wherein the elastic blade is an ultraviolet curable composition containing a (meth) acrylate compound at least on an image carrier contact portion of an elastic blade preform formed of polyurethane rubber. There is an impregnated portion that has been impregnated and UV-cured, and the variation in the longitudinal direction of Martens hardness measured from the surface at a position 20 [μm] away from the tip ridge line portion in a plane perpendicular to the horizontal surface of the elastic blade impregnated portion, A cleaning blade characterized by being 35% or less. An image carrier;
Charging means for charging the surface of the image carrier;
Latent image forming means for forming an electrostatic latent image on the surface of the charged image carrier;
Developing means for developing the electrostatic latent image formed on the surface of the image bearing member into a toner image;
Transfer means for transferring the toner image on the surface of the image carrier to a transfer body;
In an image forming apparatus provided with a cleaning unit having a cleaning blade that contacts the surface of the image carrier and cleans transfer residual toner attached to the surface of the image carrier.
An image forming apparatus using the cleaning blade according to claim 7 as the cleaning blade.   In a process cartridge that integrally supports an image carrier and a cleaning unit having a cleaning blade that removes at least transfer residual toner attached to the surface of the image carrier, and is detachable from the main body of the image forming apparatus, the cleaning blade A process cartridge using the cleaning blade according to claim 7.

Images