JP2009300551A - Cleaning blade and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning blade for preventing sneaking-through of a toner by preventing a stick slip phenomenon even in a low temperature condition. <P>SOLUTION: Concerning the polyurethane cleaning blade for an electrophotographic device provided with an edge part different in material and a backup layer, thickness×width of the edge part is (0.03 to 0.4)×(0.03 to 4) mm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a polyurethane cleaning blade for an electrophotographic apparatus comprising a backup layer and a layer having a different polyurethane composition at the edge portion. Examples of the electrophotographic apparatus include an electrophotographic copying machine, a printer, and a facsimile. In particular, the present invention relates to a manufacturing method and a manufacturing apparatus for a cleaning blade made of thermosetting polyurethane.

The present applicant has continuously proposed inventions related to a cleaning blade made of polyurethane for an electrophotographic apparatus comprising a backup layer and a layer having a different polyurethane composition at the edge portion.
In Patent Document 1 (Japanese Patent Application Laid-Open No. 2007-30385), a continuous molding method is used, and a synthetic resin is used as a molding raw material by using a molding drum having a molding groove on the outer periphery and a heating device inside. In the method of continuously forming the raw material of the blade, a method of manufacturing a blade raw material combining different materials by separately casting two or more different liquid synthetic resin raw materials was proposed.
In Patent Document 2 (Japanese Patent Laid-Open No. 2007-163676), a casting method is used, and a liquid synthetic resin that forms a partial layer is cast into a bead shape in one mold of a split mold. Later, a method of manufacturing a blade was proposed in which a mold was assembled, a liquid synthetic resin for forming a base layer was cast, and then heat cured to form a blade material.
In this type of double-layered cleaning blade, a urethane compound with excellent wear resistance and chipping resistance is used for the contact surface (edge part) with the mating material, but the compound tends not to exhibit elasticity at low temperatures. There is. Therefore, under low temperature conditions, there is a problem that the edge portion inhibits the elasticity of the backup layer, the elasticity of the entire blade is impaired, a stick-slip phenomenon occurs, and toner slips out.

JP 2007-30385 A JP 2007-163676 A

  An object of the present invention is to provide a cleaning blade that can prevent toner from slipping through without causing a stick-slip phenomenon even under low temperature conditions.

  The inventor of the present application has completed the invention by pursuing a range in which the range of the edge portion can be limited while maintaining the cleaning performance while exhibiting the backup layer characteristics that are less affected by low temperatures.

The main solution of the present invention is as follows.
(1) A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
A cleaning blade characterized in that the thickness x width of the edge portion is 0.03 to 0.4 x 0.03 to 4 mm.
(2) The cleaning blade according to (1), wherein the edge portion has a color different from that of the backup layer.
(3) The polyurethane at the edge portion is made of ester polyurethane,
The cleaning blade according to (1) or (2), wherein the polyurethane of the backup layer comprises an ether-based polyurethane.
(4) The cleaning blade according to any one of (1) to (3), wherein a tan δ peak temperature according to the following measurement conditions of the backup layer is −20 to 5 ° C.
Tanδ measurement conditions (temperature dispersion)
Dynamic strain: 0.1%
Frequency: 10Hz
Temperature rising speed: 2 ° C / min
(5) The cleaning blade according to any one of (1) to (4), wherein the ether-based polyurethane constituting the backup layer is made of polyoxytetramethylene glycol-based urethane or polypropylene glycol-based urethane.
(6) A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
A molding drum having a molding groove on its outer periphery and a heating device inside. The synthetic drum feeding means and the molding drum rotate while covering the molding groove of the molding drum along the outer periphery of the molding drum. Endless belts that rotate in synchronization are arranged in sequence, and a belt-shaped blade material having a predetermined width and thickness is formed by a molding space formed by the endless belt and the molding grooves from the synthetic resin material supplied to the molding grooves. A method of manufacturing a cleaning blade using a method of manufacturing according to the rotation of
The polyurethane material forming the edge layer is first poured into a cylindrical mold and cured while rotating the mold, and after semi-curing, the polyurethane material forming the backup layer is cured by pouring and rotating. After taking out the band-shaped blade material composed of and cutting the length to a fixed size,
The width dimension of the predetermined edge portion is within 0.03 to 4 mm,
A method for manufacturing a cleaning blade, wherein the thickness of the predetermined edge portion is cut into a predetermined edge dimension within 0.03 to 0.4 mm and molded.
(7) A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
In a manufacturing method of a cleaning blade using a split mold method in which a liquid polyurethane raw material is cast into a cavity formed by assembling two mold members, and is demolded after polymerization and curing,
Before assembling the mold, apply a liquid polyurethane raw material to form the edge part in a streak shape on the wall surface of one split mold,
Molded after semi-curing,
Injecting polyurethane raw material to form a backup layer,
Cured and demolded to obtain blade material,
The blade material as a width dimension of a predetermined edge portion is within 0.03 to 4 mm,
A method for manufacturing a cleaning blade, wherein the thickness of the predetermined edge portion is cut into a predetermined edge dimension within 0.03 to 0.4 mm and molded.
(8) The method for producing a cleaning blade according to (6) or (7), wherein the polyurethane raw material forming the edge portion is an ester polyurethane raw material, and the polyurethane raw material forming the backup layer is an ether polyurethane raw material.
(9) The method for producing a cleaning blade according to any one of (6) to (8), wherein a polyurethane colored in a color different from the polyurethane forming the backup layer is used as the polyurethane forming the edge portion .

The cleaning blade of the present invention is a cleaning blade in which the edge portion and the backup layer are made of polyurethane having different compositions, and the size of the edge portion in the cross section of the cleaning blade is 0.03 to 0.4 × in thickness × width. By setting the thickness to 0.03 to 4 mm, it is possible to maintain the cleaning performance even under a low temperature condition, and it is possible to suppress the occurrence of defective printing due to toner slipping. It can be confirmed that 0.03 mm (30 μm) to 4.0 mm is favorable in the width direction, and is good within 2.0 mm, more preferably within 0.5 mm, and within 0.2 mm in the thickness direction. Preferably, it is good within 0.1 mm. It was confirmed that the minimum edge dimension was effective up to a size of 0.03 × 0.03 mm (30 × 30 μm).
It is preferable that the edge portion has hardness and rebound resilience that maintain the scraping performance of the toner, and the backup layer has a tan δ peak temperature of −20 to 5 ° C. that ensures the stability of the physical properties of the entire cleaning blade.
When an edge portion made of ester polyurethane is combined with a backup layer made of ether polyurethane, the edge polyurethane specified by the size of the present invention has less temperature dependency and the ether polyurethane makes the edge portion temperature dependent. The toner can be buffered to prevent the toner from slipping through. When the edge portion is colored, measurement of the edge portion and trimming are facilitated.
The cleaning blade of the present invention can use continuous forming means or split mold forming means.

  The present invention is a polyurethane cleaning blade that scrapes off toner composed of two layers of an edge portion and a base backup layer, and the size of the edge portion is specified so that an excellent function can be exhibited even at low temperatures. It is an invention. As the polyurethane, a thermosetting polyurethane is suitable. An ester polyurethane is suitable as an edge polyurethane, and an ether polyurethane is suitable as a polyurethane forming a backup layer.

  A sectional view of the cleaning blade of the present invention is shown in FIG. A cleaning blade having a thickness × width of 0.03 to 0.4 × 0.03 to 4 mm, centering on an edge portion that is press-contacted to the surface of a roll or the like to scrape off toner. . Furthermore, it is at least 30 μm or more in the thickness direction and is within 0.4 mm, preferably within 0.2 mm, more preferably within 0.1 mm, and at least 30 μm or more in the width direction and within 4 mm, preferably Is within 2 mm, more preferably within 0.5 mm.

If the edge portion exists in a size outside the above range (for example, conventional two-color blade: width dimension 5 mm, thickness dimension 1 mm), the elasticity of the backup layer at low temperature cannot be sufficiently exerted, and the blade as a whole Since the elasticity of the toner is impaired, toner slips through. The minimum function as an edge is 30 × 30 μm.
If the edge portion has a color different from that of the backup layer, the size of the edge portion can be clearly identified. It becomes easy to trim and form the edge size after the polyurethane is cured.

<Blade shape and configuration>
The cleaning blade main body of the present invention is configured, for example, by adhering a polyurethane cleaning blade including a partial layer 1 at an edge portion and a base layer 2 as a backup layer to a support member 4 as shown in FIG. In the present invention, the size of the cross section of the partial layer 1 is specified as described above. In the present invention, it is basically preferable to use ester polyurethane for the edge portion and ether polyurethane for the base portion.

<Types of polyurethane>
The blade used in the present invention is suitably made of a thermosetting polyurethane resin.
As the urethane forming material, a polyurethane composition containing a polyisocyanate and a polyol is used.
As the polyol component, a layer including an edge portion or a nip portion uses an ester-based polyurethane, and a base portion other than the layer including an edge portion or a nip portion uses an ether-based polyurethane.
The polyurethane raw material used in the present invention is preferably non-solvent type thermosetting. For example, ester polyurethane and ether polyurethane disclosed in Japanese Patent Application No. 2007-18162 filed earlier by the present applicant can be used. If a colorant is added to the edge portion polyurethane resin to give a color different from that of the backup layer, the size of the edge portion can be clearly identified. It becomes easy to trim and form the edge size after the polyurethane is cured.

(1) Ester polyol
As the ester-based polyurethane forming the edge layer used in the present invention, conventionally used ester-based polyurethane can be used. Polyester polyols such as polyester diol and polyester triol. By setting the tan δ peak temperature to -20 to 5 ° C, ester polyurethane can be used as a backup layer.
The polyester polyol is produced from a polybasic organic acid and a polyol. Polycaprolactone polyols such as polycaprolactone diol obtained from ring-opening polymerization of ε-caprolactam can also be used.
Polybasic organic acid is not particularly limited, saturated fatty acids such as oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, isosebacic acid, maleic acid, Examples thereof include unsaturated fatty acids such as fumaric acid, and dicarboxylic acids such as aromatic acids such as phthalic acid, isophthalic acid and terephthalic acid. In addition, acid anhydrides such as maleic anhydride and phthalic anhydride, and dialkyl esters such as dimethyl terephthalate can also be used. Furthermore, dimer acid obtained by dimerization of unsaturated fatty acid can also be used. These may be used alone or in combination of two or more.

  The polyol is not particularly limited, and diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, 1,6-hexylene glycol, trimethylolethane, Examples include triols such as trimethylolpropane, hexanetriol, glycerin, hexaols such as sorbitol, polybutylene adipate (PBA), polyethylene adipate, and the like. These may be used alone or in combination of two or more.

(2) Ether type polyol In this invention, ether type urethane is used as a backup layer.
Polyether polyols such as polyoxytetramethylene glycol and polypropylene glycol.
Examples of the polyether polyol include cyclic ethers such as ethylene oxide, propylene oxide, trimethylene oxide, butylene oxide, α-methyltrimethylene oxide, 3,3′-dimethyltrimethylene oxide, tetrahydrofuran, dioxane, and dioxamine.

(3) Polyisocyanate
The polyisocyanate is not particularly limited. For example, 4,4'-diphenylmethane diisocyanate (MDI), 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2, 6-TDI), 3,3′-vitrylene-4,4′-diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 2,4-tolylene diisocyanate uretidinedione (2,4-TDI) Dimer), 1,5-naphthylene diisocyanate, metaphenylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate (hydrogenated MDI), carbodiimide-modified MDI, orthotoluidine diisocyanate, xylene Diisocyanate, paraphenylene diisocyanate, diisocyanate such as lysine diisocyanate methyl ester, triisocyanate such as triphenylmethane-4,4 ′, 4 ″ -triisocyanate, and polymeric MDI. These may be used alone or in combination of two or more. Of these, MDI is preferred from the viewpoint of wear resistance.

(4) Other materials In addition to the above polyisocyanates and polyols, polyurethane compositions typically include chain extenders, surfactants, flame retardants, colorants, fillers, plasticizers, stabilizers, mold release agents, catalysts, etc. The agent currently used can be mix | blended.

  The chain extender is not particularly limited as long as it is a conventionally known one. For example, 1,4-butanediol (1,4-BD), ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, Hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, xylene glycol, triethylene glycol, trimethylolpropane (TMP), glycerin, pentaerythritol, sorbitol, 1,2,6-hexanetriol, etc. Examples include polyols having a molecular weight of 300 or less. These may be used alone or in combination of two or more.

Examples of the catalyst include amine compounds such as tertiary amines and organometallic compounds such as organotin compounds. Of these, amine compounds are preferred.
Examples of the tertiary amine include trialkylamines such as triethylamine, tetraalkyldiamines such as N, N, N ′, N′-tetramethyl-1,3-butanediamine, aminoalcohols such as dimethylethanolamine, Ethoxylated amines, ethoxylated diamines, ester amines such as bis (diethylethanolamine) adipate, triethylenediamine, cyclohexylamine derivatives such as N, N-dimethylcyclohexylamine, N-methylmorpholine, N- (2 Morpholine derivatives such as -hydroxypropyl) -dimethylmorpholine and piperazine derivatives such as N, N'-diethyl-2-methylpiperazine and N, N'-bis- (2-hydroxypropyl) -2-methylpiperazine It is done.
Examples of the organic tin compound include dialkyltin compounds such as dibutyltin dilaurate and dibutyltin di (2-ethylhexoate). Moreover, 2-ethyl caproic acid stannous, oleic acid stannous, etc. are mention | raise | lifted.

(5) Resin Example The synthetic resin used in the present invention is mainly a thermosetting polyurethane resin. In particular, a non-solvent two-component thermosetting polyurethane is suitable. In the continuous molding method using the outer peripheral molding groove rotating drum, the time from casting to taking out is within one rotation of the forming drum, and it is necessary to be polymerized and solidified so that it can be taken out in about 30 to 60 seconds. Select and design isocyanates and polyols, crosslinking agents, and catalysts that satisfy these conditions. In the step after removal, secondary crosslinking and aging steps can be performed. Even when the split mold is used, it is desirable to shorten the initial curing time of the ester polyurethane used as the edge portion or the nip portion.

Examples of the additive component include a lubricant, a conductivity imparting agent, and abrasive particles.
Examples of the lubricant include silicon compounds such as polytetrafluoroethylene, boron nitride, graphite, molybdenum disulfide, and polydimethylsiloxane.
The conductivity imparting substance is not particularly limited, but carbon black such as ketjen black, acetylene black, furnace black, etc., electron conductive substances such as graphite, metal filler, metal oxide whisker, metal soap, An ion conductive substance such as perchlorate can be used alone or in combination of two or more kinds, and is applied to a developing blade or a charging blade.
The abrasive particles are applied to a blade used for the purpose of refreshing the surface of a mating material that comes into contact with the photosensitive member or the like.

For example, the polyurethane resin previously proposed in Japanese Patent No. 3004586, Japanese Patent No. 2942183, Japanese Patent No. 2645980, Japanese Patent Application Laid-Open No. 2002-214989, Japanese Patent Application Laid-Open No. 2002-214990, and the like is exemplified. The following polyurethanes can be used.
A bifunctional polyol having a number average molecular weight of 1000 to 3000, a trifunctional polyol having a number average molecular weight of 92 to 980, and a high molecular weight polyol component mixed in at least one of a liquid material of a urethane prepolymer and a liquid material of a crosslinking agent, Is mixed with a polyol having an average functional group number of 2.02 to 2.20 and a diisocyanate compound having an isocyanate group content of 5 to 20% to prepare a prepolymer, and the prepolymer is mixed with an OH group / NCO. A polyurethane liquid (uncured polyurethane composition) is prepared by mixing the crosslinking agent in an amount such that the equivalent ratio of groups becomes 0.85 to 1.00 at 40 to 70 ° C.

The number average molecular weight of the high molecular weight polyol component is preferably in the range of 1000 to 3000. By casting this composition, the reaction is carried out smoothly, and the properties of the resulting blade are also preferred. That is, the number average molecular weight of the polyol used is in the range of 1000 to 3000, and if it is less than 1000, the finished urethane rubber becomes too hard to obtain the necessary physical properties (flexibility), and exceeds 3000. And the viscosity at the time of molding is high, making it difficult to cast.
In addition, when the average number of functional groups (f) is f = 1, it becomes monool, so that it does not polymerize, and when f ≧ 5, it becomes too polyfunctional, so that the viscosity of the polymer increases and the physical properties decrease.

  The following can be used as a component for producing the polyurethane elastomer according to the present invention. Examples of polyether polyols include polyoxyalkylene glycols such as polyethylene glycol, polypropylene glycol and polyoxytetramethylene glycol, or polyether-type polyols of alkylene oxide adducts such as bisphenol A, glycerin ethylene oxide and propylene oxide. Is done. Polyester polyols include dibasic acids such as adipic acid, phthalic anhydride, isophthalic acid, maleic acid and fumaric acid, and ethylene glycol, propylene glycol, 1,4 butanediol, 1,6 hexanediol, trimethylolpropane Mention may be made of polyester polyols and polycaprolactone diols obtained by polymerization reactions with glycols.

  Examples of the diisocyanate compound include tolylene diisocyanate, 4,4 diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 1,4 cyclohexane diisocyanate, and the like. Examples of the chain extender include low molecular weight diols such as ethylene glycol, 1,4 butanediol, diethylene glycol, 1,6 hexanediol, and neopentyl glycol, and diamines such as ethylenediamine, hexamethylenediamine, and isophoronediamine. Desirably, a low molecular weight diol is used. Furthermore, you may add a trimethylol propane, a triethanolamine, glycerol, and these ethylene oxide and a propylene oxide adduct as a polyfunctional component as needed.

  In the production of the above polyurethane, the equivalent ratio of OH group / NCO group is preferably 0.8 to 1.05, preferably 0.85 to 1.00, from the physical properties of the polyurethane to be produced. Moreover, reaction accelerators, such as a general amine compound and an organic tin type compound, are used as needed. For example, the reaction accelerator disclosed in Japanese Patent No. 2942183, paragraph 0022 is an imidazole derivative or the like represented by the following general chemical formula, and specific examples thereof include a reaction temperature highly dependent on the chemical structure. Examples thereof include 2-methylimidazole and 1,2 dimethylimidazole.

In the formula, R represents hydrogen, a methyl group, or an ethyl group.

  Such a reaction accelerator is used in an amount of 0.01 to 0.5 parts by weight, preferably 0.05 to 0.3 parts by weight, based on 100 parts by weight of the prepolymer as an effective amount. Desirably, those having a temperature sensitivity or a slow-acting property can be preferably used because the usable time of the mixed resin can be increased and the demolding time is shortened. Specific examples thereof include 1,8-diazabicyclo (5,4,0) undecene-7-organic acid salt called block amine, 1,5-diazabicyclo (4,3,0) nonene-5-organic acid. Examples thereof include a salt or a mixture thereof. In this invention, a commercially available thing can be used for the two-component mixing casting machine used for mixing and stirring the liquid material of the urethane prepolymer which is the raw material component of the thermosetting polyurethane and the liquid material of the crosslinking agent. In consideration of the quantitative accuracy, the metering pump preferably uses three or more plunger types, but a gear pump type can also be used. In particular, in the production apparatus of the present invention, it is necessary to use a reaction accelerator in order to obtain a predetermined hardness at the time of demolding, and therefore, a stirring and mixing chamber is disclosed in Japanese Patent Publication No. 6-11389. A small-capacity type that prevents stagnation in the mixing chamber and suppresses heat generation due to reaction heat is preferable.

  Although the two-component thermosetting polyurethane resin is illustrated in detail, the blade resin that can be used in the present invention is not limited to this. Either a thermoplastic resin or a thermosetting resin can be used. Since a heated rotating molding drum is used, the non-solvent type containing no solvent is preferable because the thermosetting reaction is started immediately after casting.

  By blending these synthetic resin components, a resin composition to be a partial layer and a resin composition to be a base layer are prepared and used. In general, a synthetic resin serving as a partial layer used in the edge portion is designed to have high hardness and high resilience, and a resin used in the base layer is designed to have lower hardness and low resilience than the edge layer.

<Blade manufacturing method>
The method of forming the polyurethane layer of the edge part and the polyurethane layer of the base part layer is as follows: (a) a continuous molding method using a rotary molding drum having grooves formed on the outer periphery; A molding method can be used.
(1) Method of Continuous Molding Using a Rotating Molding Drum with Grooves on the Outer Peripheral This molding means can use the means disclosed in Japanese Patent Application Laid-Open No. 2007-30385 previously proposed by the inventor of the present application. . Continuously produce a synthetic resin tape having a width that is the same as or slightly larger than the width of the synthetic resin elastic rubber used in the blade, cut the long tape to a fixed size, A technique for joining a side edge of a metal support and finishing it to a developing blade, a cleaning blade or the like is a basic manufacturing method.
The basic manufacturing means used for this manufacturing method is to continuously cast a liquid material such as polyurethane into the forming groove from the vicinity of the apex while rotating a forming drum having a forming groove on the outer periphery around the horizontal axis, and forming drum A continuous molding such as polyurethane which is polymerized during the rotation operation and becomes tape-like at a position before the casting position is peeled off, taken out from the molding groove, and supplied to the subsequent process. Since tape-shaped moldings are continuously produced, in the subsequent process, a series of operations such as cutting to a single standard, joining to a metal support, and so on can be carried out continuously. Is expensive.

This continuous molding method includes a plurality of casting machines. This is a method for producing a synthetic resin blade material having two partial synthetic resin layers by continuously supplying synthetic resins having different compositions from the respective casting machines to the molding grooves of the molding drum. When the casting port is arranged at the front and back of the molding groove of the continuously rotating molding drum, it hardens with the synthetic resin cast later on the synthetic resin cast earlier. Layer is formed. The position, width, and thickness of the resin layer can be controlled by the position, supply amount, composition and type of the synthetic resin, and the rotational speed of the molding drum. The synthetic resin to be cast later is supplied in an amount necessary for filling the whole, and forms a base layer.
When the preceding synthetic resin is cast in the corner portion of the molding groove, a blade material in which a different material is provided at the edge portion can be manufactured. When casting in the middle part, a different material can be provided in the middle of the blade material.
The basic configuration is shown in FIG.
As shown in FIG. 3, the blade material manufacturing apparatus, which is an elastic rubber member, includes a molding drum 13 having molding grooves formed on the outer periphery, a first casting machine mixing head 11 that supplies a resin, and a second injection head. It comprises a casting machine mixing head 12, an endless belt 14 having a steel mirror surface, a cooling conveyor 20, a cutting device 24, a carry-out conveyor 25, and the like.

  A blade material provided with a different material layer at the edge portion is suitable for a cleaning blade that contacts the edge portion. In addition, by combining different materials, the physical property value of the elastic rubber can be controlled, so that it is possible to improve the temperature change suitability such as the high temperature range and the low temperature range, or wear resistance. Moreover, the continuous molding method of the synthetic resin tape using this molding drum can use each manufacturing method and component already proposed by the present applicant.

The synthetic resin cast in the molding groove receives heat from the molding drum in an area covered with a rotating metal endless belt provided in a state where the molding groove is covered on a part of the outer periphery of the molding drum. Thus, at a position where the curing polymerization proceeds and the endless belt is separated from the forming drum, it is formed in a tape shape having a cross-sectional shape of the groove. It is the same as the conventional proposal that a continuous synthetic resin tape can be obtained by pulling out this tape from the molding groove.
In this method, the resin is removed from the molding groove within several tens of seconds (for example, about 30 to 60 seconds) after resin casting, is not pressurized for molding, and polymerization curing is performed in the lower half of the rotating molding drum. Is the center, and it is possible to reduce the peeling angle from the molding groove, so that the peeling from the bottom of the molding groove is relatively easy, and it is not always necessary to use a release agent. . When the toner is made finer or colored, the release agent may have an adverse effect. In one embodiment of the present invention, such a problem does not occur when the release agent is not used. In addition, the fact that it is not necessary to use a mold release agent enables other surface treatment agents to act, and can be used positively for surface modification.

Further, in order to control the polymerization, an external heating means for heating toward the groove of the molding drum can be provided between the synthetic resin supply position and the endless belt. In the vicinity of the tape take-out portion, it is possible to provide a cooling means for blowing cold air or the like from the outside in order to facilitate peeling. As for the size of the resin tape obtained in the present invention, both the width and the thickness can sufficiently satisfy the range of a developing blade and a cleaning blade that are conventionally used. For example, a thickness of about 0.40 to 3.00 mm can be sufficiently manufactured.
A schematic diagram of the molding process is shown in FIG.

An example of forming a partial layer in an arc shape is schematically shown.
This example is an example based on actually measured values obtained on a trial basis, and is not limited thereto. FIG. 5 shows an elastic rubber member having a base layer 2 and an arc-shaped partial layer 1. The arc is schematically treated as an arc as follows. It can be assumed that the arc-shaped partial layer 1 is a partial arc having an imaginary radius R, twice the chord X is wide, and the height is the height Y of the arc.
The relationship between the width X and the height Y is graphed and shown in FIG. A cleaning blade having a desired edge size can be manufactured by trimming the polyurethane elastic rubber member obtained in this way so that the partial layer 1 has a predetermined thickness and width and cutting and molding. it can. If the edge portion and the base portion are colored in different colors, the cutting position can be easily determined.
(2) Individual molding method using split mold (split mold molding method)
The split mold method combines two mold members that mold a cavity corresponding to the size of a single polyurethane elastic blade, casts a liquid polyurethane material into the cavity, and after polymerization and curing. It is manufactured by demolding. Before forming the mold, apply a liquid ester-based polyurethane raw material that forms a streak-like edge to the wall surface of one of the split molds, and after semi-curing, mold the mold to form an ether-based polyurethane raw material that forms the base It is injected, cured, and demolded to obtain a blade material in which two partial layers are formed.
The method disclosed in Japanese Patent Application Laid-Open No. 2007-163676 filed by the present applicant can be used for the method of forming the partial two layers by the split mold.
That is, it is as follows.
After moving the head for discharging the liquid synthetic resin, which is a thermosetting resin, to a position corresponding to the partial layer, or by casting so that the thermosetting resin is applied in a bead shape by moving the mold, A split mold is assembled, a thermosetting resin as a base is cast, and is integrally formed in a heating furnace. The integrally formed blade material is disassembled and taken out from the split mold, cut into a predetermined size, and used as a blade. When a mold is assembled, a part of the support is set inside the cavity, and the base-forming resin is cast to integrally bond the support and the blade rubber body.

(A) Mold
FIG. 7 shows a schematic sectional view of the split mold structure.
The mold 110 includes left and right divided molds 110a and 110b. In the middle of the divided molds 110a and 110b, a projecting member is formed for sandwiching the core metal AA serving as a support member. The split molds 110a and 110b are disposed between a base plate 113, a side wall 114 standing on the left and right of the base plate 113, and an inclined side wall 115, and a mold clamping member 116 is pushed in a wedge shape toward the inclined side wall 115. Thus, the mold is clamped and assembled. A blade is molded by casting a synthetic resin serving as a base into a space formed between the two split molds 110a and 110b.
The example shown in FIG. 7 shows an example in which the core metal AA is arranged and the resin heat molding and the core metal are joined at the same time. It is also possible to manufacture a blade by molding a blade material obtained by curing the resin without arranging the core metal AA, and then joining the support member.
FIG. 8 shows a state in which the resin forming the divided layer is discharged from one of the divided molds (110a or 110b) from the discharge head 108 in a longitudinal direction and a bead shape. As the partial layer casting means, for example, a method of moving the ejection head and two methods of moving the split mold can be adopted.

  The manufacturing means used was a method of continuous molding using a rotary molding drum having grooves on the outer periphery. See Figure 3 for manufacturing equipment.

<Cleaning blade>
Elastic rubber member made of polyurethane: thickness 2.0mm, width 12.3mm, length 326mm
Edge size: The size shown in Table 2 Metal support: Steel plate with a thickness of 1.2 mm Adhesion treatment: Use of dimer acid-based hot melt adhesive

<Thermosetting polyurethane>
Table 1 shows the blending of ester urethane and ether urethane used for the edge layer or base layer.

<Evaluation test>
Evaluation machine: A commercially available printer is used. Ricoh Co., Ltd. CX9800 (with polymerization toner)
Evaluation pattern-Endurance evaluation (23 ° C x 53%) 100,000 sheets passed through The image pattern was printed with 5% area cover.
Performed by measuring the occurrence of poor cleaning due to toner slipping, toner fusing, and blade wear depth. • Performed with cleaning performance evaluation (10 ° C x 15%). Image pattern is 15mm wide x 250mm long (x 3 locations). After outputting 50 belt images,
Collect the toner that slips through the photoconductor with a mending tape and measure the width of the slipping through.

[Discussion]
As an edge part dimension, various settings were made in the range of thickness 0.03 to 2.0 mm and width 0.03 to 8.0 mm, and as a result of testing, it was possible to perform 100,000 test prints at room temperature. No toner slip occurred. On the other hand, there was an example in which initial printing failure occurred at low temperatures.
At the time of starting in a low-temperature environment (about 10 sheets in the initial stage), as can be confirmed in Examples 1 to 15, it can be confirmed that 0.03 mm (30 μm) to 4.0 mm in the width direction is good, and the thickness In the direction, 0.03 mm (30 μm) to 0.4 mm was confirmed to be favorable. Furthermore, in the width direction, it is good within 2.0 mm, more preferably within 0.5 mm. In the thickness direction, it is good within 0.2 mm, more preferably within 0.1 mm.
In this test, it was confirmed that the minimum edge size was effective up to a size of 0.03 × 0.03 mm.
When either one exceeded 4.0 mm or more in the width direction and 0.4 mm or more in the thickness direction, initial toner slippage was observed at low temperatures.

The figure which shows the cross section of a cleaning blade typically. The figure which shows the example of a cleaning blade apparatus. The figure which shows the example of the apparatus which manufactures a cleaning blade continuously. The figure which shows the hardening process of the polyurethane in a cleaning blade continuous molding method. The figure which shows the example of the partial layer formed in arc shape. The graph which shows the magnitude | size of the arc-shaped partial layer formed. Sectional drawing which shows the outline of a split mold structure. The figure which shows the outline which forms the polyurethane resin for partial layers in one side of a split mold in bead shape.

Explanation of symbols

1 Partial layer (edge, nip)
2 Base layer 3 Elastic rubber member (cleaning blade)
4 Support Member 5 Blade Cross Section 10 External Heating Device 11 First Casting Machine Mixing Belt 12 Second Casting Machine Mixing Belt 13 Forming Drum 14 Endless Belt 15 Rotating Shaft 16 Preheating Roll 17 Guide Roll 18 Tension Roll 19 Cooling Roll 20 Cooling Conveyor 21 Cooling device 22 Slack detector 23 Feed roll 24 Cutting device 25 Conveyor 26 Upper sensor 27 Lower sensor 101 Strip blade material 103 Standard size blade member 108 Discharge head 110 Mold 110a, 110b Split mold 111 Note on split mold Molding device 112 Slide plate 113 Base plate 114 Side wall 115 Inclined side wall 116 Clamping member

Claims (9)

A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
A cleaning blade characterized in that the thickness x width of the edge portion is 0.03 to 0.4 x 0.03 to 4 mm.   The cleaning blade according to claim 1, wherein the edge portion has a color different from that of the backup layer. The polyurethane of the edge part is made of ester polyurethane,
The cleaning blade according to claim 1 or 2, wherein the polyurethane of the backup layer is made of ether-based polyurethane. The cleaning blade according to any one of claims 1 to 3, wherein a tan δ peak temperature of the backup layer according to the following measurement condition is -20 to 5 ° C.
Tanδ measurement conditions (temperature dispersion)
Dynamic strain: 0.1%
Frequency: 10Hz
Temperature rising speed: 2 ° C / min   The cleaning blade according to any one of claims 1 to 4, wherein the ether-based polyurethane constituting the backup layer is made of polyoxytetramethylene glycol-based urethane or polypropylene glycol-based urethane. A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
A molding drum having a molding groove on its outer periphery and a heating device inside. The synthetic drum feeding means and the molding drum rotate while covering the molding groove of the molding drum along the outer periphery of the molding drum. Endless belts that rotate in synchronization are arranged in sequence, and a belt-shaped blade material having a predetermined width and thickness is formed by a molding space formed by the endless belt and the molding grooves from the synthetic resin material supplied to the molding grooves. A method of manufacturing a cleaning blade using a method of manufacturing according to the rotation of
The polyurethane material forming the edge layer is first poured into a cylindrical mold and cured while rotating the mold, and after semi-curing, the polyurethane material forming the backup layer is cured by pouring and rotating. After taking out the band-shaped blade material composed of and cutting the length to a fixed size,
The width dimension of the predetermined edge portion is within 0.03 to 4 mm,
A method for manufacturing a cleaning blade, wherein the thickness of the predetermined edge portion is cut into a predetermined edge dimension within 0.03 to 0.4 mm and molded. A polyurethane cleaning blade for an electrophotographic apparatus having an edge portion and a backup layer made of different materials,
In a manufacturing method of a cleaning blade using a split mold method in which a liquid polyurethane raw material is cast into a cavity formed by assembling two mold members, and is demolded after polymerization and curing,
Before assembling the mold, apply a liquid polyurethane raw material to form the edge part in a streak shape on the wall surface of one split mold,
Molded after semi-curing,
Injecting polyurethane raw material to form a backup layer,
Cured and demolded to obtain blade material,
The blade material as a width dimension of a predetermined edge portion is within 0.03 to 4 mm,
A method for manufacturing a cleaning blade, wherein the thickness of the predetermined edge portion is cut into a predetermined edge dimension within 0.03 to 0.4 mm and molded.   8. The method of manufacturing a cleaning blade according to claim 6, wherein the polyurethane raw material forming the edge portion is an ester polyurethane raw material, and the polyurethane raw material forming the backup layer is an ether polyurethane raw material. The method for manufacturing a cleaning blade according to any one of claims 6 to 8, wherein a polyurethane colored in a color different from that of the polyurethane forming the backup layer is used as the polyurethane forming the edge portion.