JP2011085783A - Developer carrier and developing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a developer carrier that prevents a change in uniformity of a triboelectric charge distribution of toner even in long-term use, and prevents image defects such as blotches. <P>SOLUTION: The developer carrier includes a substrate and a resin layer as a surface layer. The resin layer contains a thermosetting resin as a binder resin, a silicone oil having a specified structure, and an acrylic resin having a specified structure. The silicone oil is unevenly distributed in the surface side of the resin layer. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a developer carrying member and a developing device.

  Patent Document 1 discloses a developer carrier containing a quaternary ammonium base-containing copolymer on the surface layer. Specifically, it is described that the inclusion of a quaternary ammonium base-containing copolymer in the surface layer improves the negative charge imparting property to the toner, and the image density is improved when a negatively charged toner is used. ing.

JP 2002-268371 A

  In order to meet the demand for higher image quality of electrophotographic images, toner that has been finely divided and spheroidized tends to be excessively charged by friction (charge-up), and the charge amount tends to be non-uniform. In this case, white spots (hereinafter also referred to as “blotches”) may occur in the electrophotographic image. This phenomenon is particularly likely to occur with fresh toner that has not deteriorated. On the other hand, as the electrophotographic apparatus is used, the toner may deteriorate with time, the triboelectric chargeability may be lowered, and the density of the electrophotographic image may be lowered. Accordingly, the present inventors have recognized that it is necessary to develop a charging member that can compensate for changes in the charging performance of toner over time.

  Accordingly, an object of the present invention is to provide a developer carrying member that can compensate for a change in charging performance of the toner itself over time and can provide a stable and uniform triboelectric charge to the toner regardless of the degree of toner deterioration. It is in.

  Another object of the present invention is to provide a developing device that can stably provide a high-quality electrophotographic image even after long-term use.

  The developer carrier according to the present invention has a base and a resin layer as a surface layer, and the resin layer includes a thermosetting resin as a binder resin, a silicone oil represented by the following chemical formula (1), And an acrylic resin having a unit represented by the following chemical formula (2) and a unit represented by the following chemical formula (3), wherein the silicone oil is unevenly distributed on the surface side of the resin layer, To:

[In the chemical formula (1), at least one of R 1 to R 6 is an amino group or a polyether group, and the other R 1 to R 6 are independently an alkyl group having 1 to 4 carbon atoms. m is an integer of 5 or more. ];

[In the chemical formula (2), R7 is a hydrogen atom or a methyl group, and R8 is an alkyl group having 8 to 18 carbon atoms. ];

[In the chemical formula (3), R9 is a hydrogen atom or a methyl group, R10 is an alkylene group having 1 to 4 carbon atoms, R11 to R13 are independently an alkyl group having 1 to 18 carbon atoms, and X ⁻ is Anion. ].

  The developing device according to the present invention includes a negatively chargeable developer having toner particles, a container containing the developer, and the developer carrier. .

  According to the present invention, it is possible to provide a developer carrying member that can hardly suppress the occurrence of image defects such as blotches, because the uniformity of the triboelectric charge amount distribution of the toner hardly changes even after long-term use. Further, according to the present invention, it is possible to provide a developing device that can stably provide a high-quality electrophotographic image even after long-term use.

1 is a cross-sectional view of a developing device according to the present invention. 1 is a cross-sectional view of a developing device according to the present invention. 1 is a cross-sectional view of a developing device according to the present invention.

  As a result of the examination by the present inventors on the occurrence of blotch, a correlation with the excessive charging of the developer was found. That is, the fresh developer replenished in the developing container has a high triboelectric charge imparting property, and is therefore easily triboelectrically charged. Further, an excessively charged developer has a strong holding force by the developer carrying member, and the developer is difficult to move to the photosensitive member. The developer remaining on the surface of the developer carrying member without moving to the photoreceptor is further excessively charged. Thus, it was considered that the developer charged excessively had blotches.

  The developer carrier according to the present invention includes a substrate (102 in FIG. 1, 202 in FIG. 2, 302 in FIG. 3) and a resin layer (101 in FIG. 1, 201 in FIG. 2, 201 in FIG. 3) as a surface layer. Have.

<Resin layer>
The resin layer contains a thermosetting resin as a binder resin, a silicone oil represented by the chemical formula (1), and an acrylic resin having a unit represented by the chemical formula (2) and a unit represented by the chemical formula (3). is doing.

<< Thermosetting resin >>
By using the thermosetting resin as a binder resin, the durability and environmental stability of the resin layer are improved. As the thermosetting resin, a phenol resin, a melamine resin, a urea resin, or a benzoguanamine resin is preferable in terms of toughness and durability. Among these, a phenol resin is more preferable from the viewpoint of improving the abrasion resistance of the resin layer, excellent environmental stability, and excellent compatibility with an acrylic resin. Among thermosetting resins, thermosetting resins that are soluble in alcohols, particularly lower alcohols such as methanol, ethanol, propyl alcohol, and butanol are preferable because they have good compatibility with the acrylic resin used in the present invention.

<< Silicone oil >>
The resin layer contains silicone oil having a specific structure. By unevenly distributing the silicone oil near the surface of the resin layer, the lubricity of the resin layer surface can be improved, the adhesion of the developer on the surface of the developer carrier is reduced, and the occurrence of blotches is suppressed. Can do. Furthermore, since this silicone oil is more negatively charged than acrylic resin in the charging series, it is possible to suppress excessive frictional charging of the negative frictional charging developer. As a result, it is possible to suppress the occurrence of blotches particularly at the initial stage of image formation. In addition, the surface of the resin layer is gradually scraped with use, the silicone oil is removed, and the ratio of the acrylic resin according to the present invention on the surface of the developer carrier increases. As a result, the triboelectric charge amount of the developer is improved by the action of the quaternary ammonium base of the acrylic resin. The developer tends to deteriorate as a result of repeated image formation and gradually becomes difficult to be charged. However, the developer carrying member according to the present invention can stabilize the density of the electrophotographic image regardless of the state of the toner because the triboelectric charging performance of the developer is improved with use for the above reasons. . As the silicone oil, an amino-modified silicone oil or a polyether-modified silicone oil represented by the following chemical formula (1) is used.

In the chemical formula (1), one or more groups selected from R1 to R6 are amino groups or polyether groups, and when there are groups that are not amino groups or polyether groups among R1 to R6, they are independent. And an alkyl group having 1 to 4 carbon atoms. m is an integer of 5 or more. Silicone oil modified with an amino group or a polyether group has a large polarity difference from the binder resin and tends to exist more in the vicinity of the surface of the resin layer. In addition, since the silicone oil modified with an amino group or a polyether group has a large polarity difference from the acrylic resin, it tends to be more unevenly distributed near the surface of the resin layer. As a result, the effect of the silicone oil described above can be obtained more easily. Among the silicone oils represented by the chemical formula (1), the side-chain polyether-modified silicone oil represented by the following chemical formula (5) can increase the polarity, and more easily exists in the vicinity of the surface of the resin layer. preferable.

In chemical formula (5), one or both of R15 and R16 is the following chemical formula (6). Moreover, when any one group of R15 and R16 is not the following chemical formula (6), the group is an alkyl group having 1 to 4 carbon atoms. R14 and R17 to R19 are each independently an alkyl group having 1 to 4 carbon atoms. m is an integer of 5 or more.

In chemical formula (6), R20 is any one of O, C ₂ H ₄ O, and C ₃ H ₆ O. R21 is an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. q and r are each independently an integer of 0 or more, and at least one of q and r is an integer of 1 or more. n is an integer of 1 or more.

Formula _{(6) - ((C 3} H 6 O) r - (C 2 H 4 O) q) n - in made structure, repeating the order of C ₂ H ₄ O units and C ₃ H ₆ O units block type However, it may be random and may be composed of a C ₂ H ₄ O unit and a C ₃ H ₆ O unit. Further, the formula _{(6) - ((C 3} H 6 O) r - (C 2 H 4 O) q) n - comprised structure, either of C ₂ H ₄ O units or C ₃ H ₆ O units It may be composed only of units.

Further, the sum of the number of siloxane moieties of the silicone oil represented by the chemical formula (5) is A (mol), and the sum of the number of units having C ₂ H ₄ O or C ₃ H ₆ O as a structural unit is B (mol). ), It is preferable that the following general formula (7) is satisfied.

0.50 ≦ B / A ≦ 4.00 (7)
Theoretically, A is the same as m in the chemical formula (5), and B is the sum of the ether groups contained in the chemical formula (6) of the chemical formula (5). That is, B / A is a parameter indicating the modification rate of the polyether group and the length of the polyether group. The larger the numerical value, the greater the polarity and the higher the hydrophilicity. If B / A is 0.50 or more, more silicone oil is likely to be present near the surface of the resin layer. Further, by having a certain degree of polarity difference from the acrylic resin, it is possible to make it difficult for the acrylic resin to be mixed with the silicone oil near the surface. As a result, it becomes easy to obtain the effect of suppressing lubricity and excessive frictional charging of the silicone oil. In addition, when the surface is scraped during durable use, the abundance ratio of the acrylic resin on the outermost surface increases, and the triboelectric charge amount of the developer can be gradually improved. On the other hand, silicone oils with B / A exceeding 4.00 are difficult to produce industrially even if the molecular weight is lowered to increase the modification rate of the polyether group as much as possible.

  The presence of more silicone oil in the vicinity of the surface can be confirmed by measuring the abundance ratio of Si atoms within 1 μm depth from the resin layer surface and the resin layer surface by X-ray photoelectron spectroscopy. it can. The measurement method of X-ray photoelectron spectroscopy will be described later in terms of the abundance ratio of C atoms and Si atoms.

  The silicone oil represented by the chemical formula (1) can be produced by a known method. For example, a method of preparing a dimethyl silicone oil having a Si—H group and adding a polyether group to the dimethyl silicone oil can be mentioned. The synthesis of dimethyl silicone oil having a Si—H group causes a dehydrogenation reaction under alkaline conditions, and therefore a synthesis method using an acid catalyst is used.

  For example, at least one of octamethylcyclotetrasiloxane and tetramethylcyclotetrasiloxane and at least one substance of hexamethyldisiloxane, pentamethyldisiloxane, and tetramethyldisiloxane are mixed under the addition of a small amount of concentrated sulfuric acid. By reacting as it is for 8 hours or longer, dimethylsiloxane containing Si-H groups can be produced. Then, a polyether-modified dimethyl silicone oil can be produced by addition reaction of dimethylsiloxane having a Si-H group and a polyether having a carbon-carbon double bond at the molecular end in the presence of a platinum catalyst for 3 hours or more. Is possible.

  The addition amount of the silicone oil represented by the chemical formula (1) is preferably 0.5 parts by mass or more and 5 parts by mass or less with respect to 100 parts by mass of the binder resin. By setting it as this range, it becomes easy for silicone oil to exist in the surface vicinity of a resin layer, and suppression of a blotch becomes more favorable. Furthermore, the charge control effect of the acrylic resin is easily obtained, which contributes to further stabilization of the image density during continuous use.

<< Acrylic resin >>
The acrylic resin has a unit represented by the following chemical formula (2) and a unit represented by the chemical formula (3). When the resin layer contains this acrylic resin, the triboelectric charge amount of the developer by the developer carrier is improved. Further, since this acrylic resin has ionic conductivity since it has a quaternary ammonium base, the volume resistance value of the resin layer can be controlled to be low and uniform. As a result, excessive frictional charging of the developer is prevented during durable use, the image density is easily stabilized, and the occurrence of blotches is easily suppressed.

In the chemical formula (2), R7 is a hydrogen atom or a methyl group, and R8 is an alkyl group having 8 to 18 carbon atoms.

In the chemical formula (3), R9 is a hydrogen atom or a methyl group, R10 is an alkylene group having 1 to 4 carbon atoms, R11 to R13 are each independently an alkyl group having 1 to 18 carbon atoms, and X ⁻ is Anion. As the ester unit represented by the formula (2), a unit in which R7 is a methyl group and R8 is a long-chain alkyl group selected from a decyl group, an undecyl group, a dodecyl group, a tridecyl group, and a tetradecyl group is preferable. . When the alkyl group to be R8 is a long chain as described above, the compatibility of the acrylic resin with the binder resin used in the present invention is increased. Therefore, the acrylic resin is uniformly present in the resin layer, and uniform frictional charging can be imparted to the toner. In addition, since the dispersibility of pigments such as conductive particles in the resin layer is also improved, the resistance distribution is uniform and local overcharging of the developer is suppressed.

  In addition, when the alkyl group which becomes R8 is a lower alkyl group having a smaller number of carbon atoms than the range specified in the present invention, the hydrophobicity is lowered and the polarity of the entire copolymer is increased. In this case, since the polarity difference between the acrylic resin and the silicone oil is small, the compatibility with the silicone oil is increased, and it becomes difficult to contain more silicone oil near the surface of the resin layer. As a result, the lubricity of the resin layer surface is lowered, and image defects such as blotches are likely to occur.

  On the other hand, when the alkyl group to be R8 is a long-chain alkyl group (19 or more carbon atoms) exceeding the octadecyl group, although the hydrophobicity is increased, the crystallinity is increased and the compatibility with the binder resin, silicone oil and solvent is increased. Tends to deteriorate, and the binder resin and the acrylic resin are easily phase separated. As a result, when the toner comes into contact with the resin layer, a difference in frictional charging occurs due to nonuniformity of the presence state of the acrylic resin, so that the frictional charge distribution tends to be nonuniform. At the same time, the agglomeration of the conductive agent is likely to occur, so that leak sites are locally present, and the nonuniformity of the triboelectric charge distribution of the toner is increased.

As the cation unit represented by the formula (3), the following units are preferable.
R9 is a methyl group;
R10 is a methylene group or an ethylene group;
R11, R12 and R13 are each independently a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group or a tetradecyl group. A long chain alkyl group selected from:

  When the alkyl groups serving as R11, R12, and R13 are long chains, the cation units that are charging sites are uniformly present in the resin layer, and uniform triboelectric charge can be imparted to the toner. However, when R11, R12 and R13 are long-chain alkyl groups (19 or more carbon atoms) exceeding the octadecyl group, the crystallinity tends to increase and the compatibility with the binder resin, silicone oil and solvent tends to deteriorate. The binder resin and acrylic resin are easy to phase separate.

As the cation unit represented by the formula (3), the following unit is particularly preferable in that uniform triboelectric charge can be imparted.
R9 is a methyl group;
R10 is a methylene group or an ethylene group;
A long-chain alkyl group wherein R11 is selected from octyl, nonyl, decyl, undecyl, dodecyl, tridecyl and tetradecyl;
R12 and R13 each independently represents an alkyl group selected from a methyl group, an ethyl group, and a propyl group.

Examples of X ⁻ in the formula (3) include halogens; anions in inorganic acids such as sulfuric acid, phosphoric acid and nitric acid; and anions in organic acids such as carboxylic acid and sulfonic acid. An anion containing a sulfur atom or a halogen atom is preferable, and a halogen such as Br ⁻ or Cl ⁻ is more preferable because of compatibility with the binder resin used in the present invention.

  The acrylic resin usable in the present invention is, for example, a copolymer of an acrylic monomer that gives a unit represented by the chemical formula (2) and an acrylic monomer that has a quaternary ammonium base that gives a unit represented by the chemical formula (3). By doing so, it can be manufactured.

  Examples of the acrylic monomer that gives a unit represented by the chemical formula (2) include a monomer represented by the following chemical formula (8).

In the chemical formula (8), R7 is a hydrogen atom or a methyl group, and R8 is an alkyl group having 8 to 18 carbon atoms. Examples of the monomer represented by the formula (8) include acrylates in which R7 is a hydrogen atom, and methacrylates in which R7 is a methyl group. Among these, methacrylates in which R8 is a long-chain alkyl group selected from a decyl group, an undecyl group, a dodecyl group, a tridecyl group, and a tetradecyl group, and R7 is a methyl group are preferable.

  Examples of the acrylic monomer having a quaternary ammonium base that gives a unit represented by the chemical formula (3) include a monomer represented by the following chemical formula (9).

In the chemical formula (9), R9 is a hydrogen atom or a methyl group, R10 is an alkylene group having 1 to 4 carbon atoms, R11 to R13 are independently an alkyl group having 1 to 18 carbon atoms, and X ⁻ is an anion. It is. Examples of the monomer represented by the formula (9) include the following.
R9 is a methyl group;
R10 is a methylene group or an ethylene group;
R11, R12, and R13 are independently a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a nonyl group, a decyl group, an undecyl group, a dodecyl group, a tridecyl group, or a tetradecyl group. A long chain alkyl group selected from:

As the monomer represented by the formula (9), the following are particularly preferable from the viewpoint of triboelectric charge imparting ability and polarity control.
R9 is a methyl group;
R10 is a methylene group or an ethylene group;
A long-chain alkyl group wherein R11 is selected from octyl, nonyl, decyl, undecyl, dodecyl, tridecyl and tetradecyl;
R12 and R13 each independently represents an alkyl group selected from a methyl group, an ethyl group, and a propyl group.

Examples of X ⁻ in formula (9) include the following. Halogens such as fluorine, chlorine, bromine and iodine; anions in inorganic acids such as sulfuric acid, phosphoric acid and nitric acid; anions in organic acids such as carboxylic acid and sulfonic acid. Among them, preferred anions containing a sulfur atom or a halogen atom, further, Br ^-, Cl ^- and halogen are more preferable in terms of ease and manufacture of the ease of availability of raw materials.

  In producing the acrylic resin, a known polymerization method can be used. Examples of the method include a bulk polymerization method, a solution polymerization method, an emulsion polymerization method, a suspension polymerization method, and the like, but a solution polymerization method is preferable because the reaction can be easily controlled. Examples of the solvent used in the solution polymerization method include lower alcohols such as methanol, ethanol, n-butanol, and isopropyl alcohol. In addition, xylene, toluene, ethyl acetate, isobutyl acetate, methyl ethyl ketone, methyl isobutyl ketone, N, N-dimethylformamide, dimethylformamide and the like may be mixed and used as necessary. In terms of improving the compatibility with the binder resin used in the present invention, it is preferable to mainly use a lower alcohol as a solvent. Regarding the ratio of the solvent and the copolymerization monomer component, it is preferable that the copolymerization monomer component is 30 parts by mass or more and 400 parts by mass or less with respect to 100 parts by mass of the solvent from the viewpoint of controlling an appropriate viscosity.

  The polymerization of the monomer mixture can be performed, for example, by heating the monomer mixture to 50 ° C. or higher and 100 ° C. or lower in the presence of a polymerization initiator in an inert gas atmosphere. The following are mentioned as an example of the polymerization initiator used in order to superpose | polymerize. t-butylperoxy-2-ethylhexanoate, cumyl perpivalate, t-butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, di-t-butyl peroxide, t-butyl Cumyl peroxide, dicumyl peroxide, 2,2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile) ), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis (2-methylpropionate). The polymerization initiator can be used alone or in combination of two or more monomers. Usually, a polymerization initiator is added to the monomer solution to start the polymerization, but a part of the polymerization initiator may be added during the polymerization in order to reduce unreacted monomers. In addition, a method of promoting polymerization by irradiation with ultraviolet rays or an electron beam can be used, and these methods may be combined.

  The amount of the polymerization initiator used is preferably 0.05 parts by mass or more and 30 parts by mass or less with respect to 100 parts by mass of the copolymerization monomer component in terms of controlling the amount of residual monomer and the molecular weight of the acrylic resin. More preferably, it is 1 part by mass or more and 15 parts by mass or less. The temperature of the polymerization reaction is preferably 40 ° C. or higher and 150 ° C. or lower from the viewpoint of proceeding the polymerization reaction stably.

  In addition, as the monomer represented by the chemical formula (9), a monomer produced by quaternizing the monomer represented by the following chemical formula (10) with a quaternizing agent can be used.

In chemical formula (10), R9 is a hydrogen atom or a methyl group, R10 is an alkylene group having 1 to 4 carbon atoms, and R11 and R12 are independently an alkyl group having 1 to 18 carbon atoms. Examples of the quaternizing agent include the following. Alkyl halides such as butyl bromide, 2-ethylhexyl bromide, octyl bromide, lauryl bromide, stearyl bromide, butyl chloride, 2-ethylhexyl chloride, octyl chloride, lauryl chloride, stearyl chloride; methyl p-toluenesulfonate, dimethyl sulfate, hydroxynaphthalene Organic acid compounds such as methyl sulfonate. The amount of the quaternizing agent used is preferably 0.8 mol or more and 1.0 mol or less with respect to 1 mol of the monomer represented by the chemical formula (10). The quaternization of the monomer represented by the chemical formula (10) can be performed, for example, by heating the monomer represented by the chemical formula (10) and the quaternizing agent to 60 ° C. or higher and 90 ° C. or lower in a solvent. .

  In addition, after the monomer represented by the chemical formula (8) and the monomer represented by the chemical formula (10) are copolymerized, the desired quaternary ammonium base-containing acrylic copolymer is obtained by quaternization with a quaternizing agent. It is also possible to obtain. In addition, for example, the monomer represented by the chemical formula (10) may be quaternized with an alkyl halide such as methyl chloride and then copolymerized with the monomer represented by the chemical formula (8). The obtained quaternary ammonium base-containing acrylic copolymer is treated with an acid such as p-toluenesulfonic acid and hydroxynaphthalenesulfonic acid to perform counterion exchange, and contains a quaternary ammonium base as a target anion species. An acrylic copolymer can also be used.

  The composition ratio of each unit in the acrylic resin is such that b / (a + b) is 0.5 when the composition ratio of the unit represented by the chemical formula (2) is a and the composition ratio of the unit represented by the chemical formula (3) is b. It is preferable that it is 0.9 or more. By setting b / (a + b) to 0.5 or more, the negative triboelectric chargeability of the acrylic resin is improved, and the ionic conductivity effect due to the quaternary ammonium salt structure is easily enhanced, so that ghosts are generated. It becomes easy to suppress. By setting b / (a + b) to 0.9 or less, the compatibility with the binder resin is improved, and the acrylic resin is likely to be uniformly present in the resin layer. The dispersibility of the conductive particles is also improved.

  In the present invention, when a plurality of types of units represented by the chemical formula (2) or the chemical formula (3) are contained in the acrylic resin, the total of the plurality of unit composition ratios represented by the chemical formula (2) is a, The total of the plural types of unit composition ratios represented by chemical formula (3) is defined as b.

  The acrylic resin may contain other units in addition to the unit represented by the chemical formula (2) and the unit represented by the chemical formula (3). The content of other units contained in the acrylic resin is preferably 30 mol% or less of the total number [mol] of units constituting the acrylic resin. By making the content rate of another unit 30 mol% or less, it is easy to obtain the effect by introducing the unit represented by the chemical formula (2) and the unit represented by the chemical formula (3). The addition amount of the acrylic resin having the unit represented by the chemical formula (2) and the unit represented by the chemical formula (3) is preferably 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the binder resin. By setting it in this range, it is possible to easily exert the charge control effect due to the addition of the acrylic resin, and the silicone oil represented by the chemical formula (1) can be easily present in the vicinity of the surface. Image defects can be easily suppressed.

The volume resistance of the resin layer is preferably 10 ⁴ Ω · cm or less, more preferably 10 ⁻³ Ω · cm or more and 10 ³ Ω · cm or less. When the volume resistance of the resin layer exceeds 10 ⁴ Ω · cm, ghost is likely to occur. As a method of adjusting the volume resistance value of the resin layer, there is a method of dispersing and containing a conductive agent. As the conductive agent, conductive fine particles having a number average particle diameter of 1 μm or less (preferably 0.01 to 0.8 μm) can be used. By setting the number average particle diameter of the conductive fine particles to 1 μm or less, it is easy to uniformly control the volume resistance of the resin layer, and to suppress the generation of ghost. Moreover, the following are mentioned as a material of a electrically conductive agent. Fine powders of metal powders such as aluminum, copper, nickel and silver; metal oxides such as antimony oxide, indium oxide, tin oxide, titanium oxide, zinc oxide, molybdenum oxide and potassium titanate; carbon fiber, furnace black, lamp Carbon black such as black, thermal black, acetylene black and channel black, and carbide such as graphite. Among these, carbon black, particularly conductive amorphous carbon is preferably used. This is because carbon black is particularly excellent in electrical conductivity, and can be obtained to some extent by simply filling the polymer material with conductivity or controlling the amount of addition.

  Moreover, you may control the volume resistance value of a resin layer using 2 or more types of these electrically conductive agents. When two or more kinds of conductive agents are used, a combination of carbon black and graphitized particles such as graphite is preferable. When carbon black and graphitized particles are used as a conductive agent, it is easy to obtain a resin layer having a uniform volume resistance and good conductivity. Furthermore, since the surface roughness of the developer carrying member can be obtained to some extent, the triboelectric charging property of the toner on the developer carrying member can be easily controlled uniformly. The addition amount of the conductive agent is preferably 1 part by mass to 100 parts by mass with respect to 100 parts by mass of the binder resin. By setting the addition amount of the conductive agent to 1 part by mass or more, the resistance value of the resin layer can be raised to a desired level. By setting the addition amount of the conductive agent to 100 parts by mass or less, the strength (abrasion resistance) of the resin layer can be maintained even when a fine powder having a submicron order particle size is used.

  The preferred range of the surface roughness of the resin layer varies depending on the development method, but it is generally preferable that the arithmetic average roughness Ra (JIS B0601-2001) is 0.15 μm or more and 3.00 μm or less. When Ra is 0.15 μm or more, the developer transport amount can be sufficient, so that the occurrence of image defects due to insufficient image density due to insufficient developer transport amount and uneven coating of the developer coat layer can be prevented. easy. Further, when Ra is 3.00 μm or less, the developer conveyance amount is stabilized, and triboelectric charging can be performed so that the toner triboelectric charge distribution is uniform. As the surface roughness of the resin layer, a measurement value obtained by a measurement method according to JIS B0601 (2001) can be adopted. As a method of adjusting the roughness of the resin layer to a desired value, a surface roughness is imparted to the substrate on which the resin layer is formed by sand blasting, and a resin layer is formed thereon, or unevenness imparting particles are provided on the resin layer. There is a method of obtaining the surface roughness by inclusion. From the viewpoint of controlling the roughness of the surface roughness at low cost and at a low cost, a method in which the unevenness imparting particles are contained in the resin layer is preferable. By adding irregularity-providing particles, the surface of the resin layer of the developer carrier is maintained at an appropriate surface roughness to improve developer transport, increase the chance of contact between the developer and the resin layer, and friction It becomes easy to improve the chargeability. In order to form appropriate irregularities on the surface of the resin layer, the irregularity-providing particles preferably have a volume average particle size of 1 to 20 μm, and more preferably 2 to 10 μm. If the volume average particle size is 1 μm or more, an appropriate surface roughness can be imparted to the resin layer even if the content is small. If the volume average particle size of the unevenness imparting particles is 20 μm or less, the roughness of the surface of the resin layer becomes uneven and the roughness becomes too large to suppress the frictional charge of the developer from becoming insufficient, It is possible to suppress deterioration in image quality such as fogging and low density in the obtained image. The measured value measured using the laser diffraction type particle size distribution meter can be employ | adopted for the volume average particle diameter of uneven | corrugated provision particle | grains. As the irregularity-providing particles, resin particles, metal oxide particles, carbonized particles and the like can be used, and as the irregularity-imparting particles, a spherical shape or a similar shape is easily dispersed uniformly in the resin layer. Therefore, it is preferable.

  Next, the manufacturing method of a resin layer is demonstrated. The resin layer can be formed, for example, by dispersing and mixing the components of the resin layer in a solvent to form a paint, coating the substrate, drying, solidifying, or curing.

  A known dispersion apparatus using beads such as a sand mill, a paint shaker, a dyno mill, and a pearl mill can be suitably used for dispersing and mixing the components forming the resin layer in the paint. In addition, as a method of applying the obtained paint to the substrate, known methods such as a dipping method, a spray method, and a roll coating method can be applied, but in order to make each component in the resin layer uniform. The spray method is preferred.

  The film thickness of the resin layer is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 4 μm or more and 30 μm or less because it is easy to form a uniform film thickness.

<Substrate>
A cylindrical member, a columnar member, and a belt-like member can be used for the substrate. Among them, a rigid cylindrical tube or a solid rod such as a metal is preferable because it has excellent processing accuracy and durability. As such a substrate, a non-magnetic metal or alloy such as aluminum, stainless steel, or brass is formed into a cylindrical or columnar shape and subjected to processing such as polishing or grinding is preferably used. Moreover, you may use as a base | substrate of this invention what formed the rubber layer or the resin layer on the above base | substrates.

  The developer carrying member according to the present invention has high lubricity on the surface of the resin layer at the initial stage, and can control the triboelectric charge amount of the developer having negative triboelectric chargeability to be moderately high. Further, since the surface is gradually scraped with use, the ratio of the acrylic resin existing on the surface of the resin layer increases, and the deteriorated developer can be stably triboelectrically charged. Therefore, the occurrence of blotch at the initial stage of use can be suppressed more effectively, and the image density over time can be further suppressed.

<Developing device>
The developing device includes a negatively chargeable developer having toner particles, a container containing the developer, the developer carrying member for carrying and conveying the developer contained in the container, and the developer. A developer layer regulating member for forming a developer layer on the surface of the carrier. In this developing device, the developer on the surface of the developer carrying member is conveyed to a developing region facing the electrostatic latent image carrying member on which the electrostatic latent image is formed, and the electrostatic latent image on the electrostatic latent image carrying member is transferred. Can be developed with the developer to form an image. The developing device may be a non-contact developing device or a contact developing device using a magnetic one-component developer or a non-magnetic one-component developer, or a developing device using a two-component developer. In particular, in a non-contact type developing device such as a magnetic one-component non-contact type developing device and a non-magnetic one-component non-contact type developing device that tend to vary in the triboelectric charge amount of the developer on the developer carrying member. The effects of the present invention can be obtained. FIG. 1 shows a schematic configuration diagram of a magnetic one-component non-contact developing device according to an embodiment of the present invention. The developing device shown in FIG. 1 carries a container (developing container 109) for containing a developer and a magnetic one-component developer (not shown) (also referred to as toner) having magnetic toner particles stored in the container. It has a developer carrier 105 of the present invention for transporting. The developer carrying member 105 is provided with a developing sleeve 103 in which a resin layer 101 is coated on a metal cylindrical tube serving as a base 102, and a magnet (magnet roller) 104 is disposed inside the developing sleeve 103, and toner is placed on the surface. It is magnetically guided to and held by. On the other hand, an electrostatic latent image carrier that carries an electrostatic latent image, for example, the photosensitive drum 106 rotates in the direction of arrow B, and the developer carrying is carried in the developing region D where the developer carrier 105 and the photosensitive drum 106 face each other. The developer on the body 105 is attached to the electrostatic latent image to form a toner image. A developing method in such a developing apparatus will be described below. Toner is fed into the developer container 109 from a developer supply container (not shown) via a developer supply member (such as a screw) 118. The developing container 109 is divided into a first chamber 112 and a second chamber 111, and the toner fed into the first chamber 112 passes through a gap formed by the developing container 109 and the partition member 113 by the stirring and conveying member 110. To the second chamber 111. A stirring member 114 is provided in the second chamber 111 to prevent the developer from staying. A magnetic blade 107 as a developer layer thickness regulating member is attached to the developer container 109 so as to face the developer carrier 105 with a gap of about 50 μm to 500 μm. The magnetic force lines from the magnetic pole N1 of the magnet roller 104 are concentrated between the magnetic blades, the developer carrier 105 rotates in the direction of arrow A, and a thin layer of toner is formed on the developer carrier 105. Instead of the magnetic blade 107, a nonmagnetic developer layer thickness regulating member may be used. The toner obtains a triboelectric charge that can develop the electrostatic latent image on the photosensitive drum 106 due to friction between the toner layers and between the resin layers 101 on the surface of the developer carrier 105. The thickness of the toner layer formed on the developer carrier 105 is preferably thinner than the minimum gap between the developer carrier 105 and the photosensitive drum 106 in the development region D.

  Further, in order to cause the toner carried on the developer carrying member 105 to fly to the electrostatic latent image on the photosensitive drum and develop it, a developing bias voltage can be applied to the developer carrying member 105 from the developing bias power source 108. preferable. When a DC voltage is used as the developing bias voltage applied to the developer carrier 105, a voltage corresponding to an intermediate value between the electrostatic latent image potential and the background potential is preferable. In order to increase the density of the developed image and improve the gradation, an alternating bias voltage may be applied to the developer carrier 105 to form an oscillating electric field whose direction is alternately reversed in the development region D. . Also in this case, the voltage applied to the developer carrying member 105 is preferably an alternating bias voltage in which a DC voltage component corresponding to an intermediate value between the electrostatic latent image potential and the background potential is superimposed. At this time, in the case of so-called regular development in which toner is attached to a high-potential electrostatic latent image, a magnetic one-component developer that is frictionally charged to a polarity opposite to the polarity of the electrostatic latent image is used. In the case of so-called reversal development in which toner is attached to a low-potential electrostatic latent image, a magnetic one-component developer that is frictionally charged to the same polarity as that of the electrostatic latent image is used. Here, the high potential and the low potential are expressions based on absolute values.

  FIG. 2 shows a schematic configuration diagram of a magnetic one-component non-contact developing device according to an embodiment of the present invention. The developing device shown in FIG. 2 includes an elastic blade 215 made of an elastic plate made of rubber such as urethane rubber or silicone rubber, or metal such as phosphor bronze or stainless steel. The other configurations of the developing device shown in FIG. 2 are the same as those of the developing device shown in FIG.

  The elastic blade 215 is brought into contact with or pressed against the developer carrier 205 via a magnetic one-component developer, and the developer is subjected to stronger restrictions than the developing device shown in FIG. A thin layer is formed on top. In this type of developing device, the toner is easily affected by non-uniform conductivity on the surface of the developer carrier, and the toner layer on the developer carrier varies in the amount of triboelectric charge, resulting in a broad triboelectric charge amount distribution. Prone. However, even in such a developing apparatus, by using the developer carrier of the present invention, since the conductivity of the surface of the developer carrier is uniform, the toner triboelectric charge distribution can be sharpened.

  Here, the contact pressure of the elastic blade 215 with respect to the developer carrying member 205 is a linear pressure of 4.9 N / m or more and 49 N / m or less, so that the regulation of the toner is stabilized and the thickness of the toner layer is suitably set. It is preferable in that it can be regulated. When the contact pressure of the elastic blade 215 is set to a linear pressure of 4.9 N / m or more, the thickness of the toner layer formed on the developer carrying member can be controlled with high precision, and fog and magnetic properties are obtained in the obtained image. Occurrence of component developer leakage can be suppressed. Further, when the linear pressure is 49 N / m or less, the rubbing force of the magnetic one-component developer becomes an appropriate level, and it is possible to prevent toner deterioration and fusion to the developer carrier 205 and the elastic blade 215. .

  FIGS. 1 and 2 show an example of a magnetic one-component non-contact type developing device. In the present invention, the magnetic one-component developer on the developer carrier is formed between the developer carrier and the photosensitive drum in the development region D. The present invention can also be suitably applied to a magnetic one-component contact type developing device that is formed to have a thickness equal to or greater than the gap distance between them.

  FIG. 3 shows a schematic configuration diagram of a non-magnetic one-component non-contact type developing apparatus according to an embodiment of the present invention. In the developing device shown in FIG. 3, an electrostatic latent image carrier, such as a photosensitive drum 306, that carries an electrostatic latent image is rotated in the direction of arrow B. A developing sleeve 303 as a developer carrying member is composed of a base (metal cylindrical tube) 302 and a resin layer 301 formed on the surface thereof. A columnar member can be used instead of the metal cylindrical tube as the base, and a non-magnetic one-component developer is used. Therefore, no magnet is provided inside the base 302.

  A developing method in such a developing apparatus will be described below. In the developing container 309, an agitating / conveying member 310 for agitating and conveying a non-magnetic one-component developer 317 (also referred to as toner) is provided. Further, a developer supply / peeling member 316 for supplying the developer to the developing sleeve 303 and stripping off the toner remaining on the surface of the developed sleeve 303 after development contacts the developing sleeve 303. It is provided in contact. The developer supply / peeling member (developer supply / peeling roller) 316 rotates in the same direction as or opposite to the developing sleeve 303 to peel off the toner remaining on the developer sleeve 303 in the developing container 309. New toner is supplied. The developing sleeve 303 carries the supplied toner and rotates in the direction of arrow A to convey the toner to the developing region D where the developing sleeve 303 and the photosensitive drum 306 face each other.

  The toner carried on the developing sleeve 303 is pressed against the surface of the developing sleeve 303 by the developer layer thickness regulating member 315, and the thickness thereof is formed constant. The toner is frictionally charged enough to develop the electrostatic latent image on the photosensitive drum 306 by friction between the toner, the developing sleeve 303, and the developer layer thickness regulating member 315. The thickness of the toner layer formed on the developing sleeve 303 is preferably thinner than the minimum gap between the developing sleeve 303 and the photosensitive drum 306 in the developing portion. The present invention is particularly effective for such a non-contact type developing apparatus.

  In order to cause the toner carried on the developing sleeve 303 to fly to the electrostatic latent image on the photosensitive drum and develop it, it is preferable to apply a developing bias voltage from the developing bias power source 308 to the developing sleeve. The development bias voltage may be either a DC voltage or an alternating bias voltage, and the voltage is preferably the same voltage as described above.

  As the developer supply / peeling member 316, for example, an elastic roller such as resin, rubber, or sponge, a belt, a brush member, or the like can be used. In the case of using an elastic roller, the same direction or the opposite direction can be selected as appropriate with respect to the developing sleeve 303, but usually rotating in the same direction (the direction of arrow C) is a point of stripping property and supply property. Is preferable. The penetration amount of the elastic roller with respect to the developing sleeve 303 is preferably 0.5 mm or more and 2.5 mm or less from the viewpoint of developer supply and stripping property. When the intrusion amount of the elastic roller is 0.5 mm or more, the peelability is improved and the occurrence of ghost can be suppressed. When the intrusion amount is 2.5 mm or less, there is little stress on the toner, and toner deterioration, fusing and fogging can be suppressed.

  The elastic blade 315 preferably has the same material and the same curved shape as the elastic blade 215 of the magnetic one-component non-contact developing device shown in FIG. 2 and is installed so as to be pressed against the developing sleeve 303. The elastic blade 315 has a structure in which a polyamide elastomer (PAE) is attached to the surface of a phosphor bronze plate that can obtain a stable pressurizing force, particularly for a stable regulation force and a stable (negative) triboelectric chargeability to the toner. It is preferable to use those. Examples of the polyamide elastomer (PAE) include a copolymer of polyamide and polyether.

  The contact of the elastic blade 315 with the developing sleeve 303 is preferably based on the same contact force as that of the elastic blade 215 with respect to the developer carrier 205 for the same reason as in the magnetic one-component non-contact type shown in FIG.

  FIG. 3 shows an example of a non-magnetic one-component non-contact type developing device, but the present invention relates to a gap distance between the developing sleeve and the photosensitive drum in the developing region D where the non-magnetic one-component developer on the developing sleeve is developed. The present invention can also be suitably applied to a non-magnetic one-component contact developing device formed with the above thickness.

  The developing device shown in FIGS. 1 to 3 is an example of the developing device according to the present invention. The developing device according to the present invention includes a developer carrier shape, a developer container shape, the presence / absence of a stirring / conveying member, and an arrangement of magnetic poles. It is not limited to the shape of the developer supply member, the presence or absence of a replenishing container, and the like.

<< Developer (Toner) >>
The developer (toner) according to the present invention will be described. The toner contains a binder resin, a colorant, a charge control agent, a release agent, inorganic fine particles, and the like. Further, it contains a magnetic material depending on the developing device to be used. The toner according to the present invention preferably has a weight average particle diameter in the range of 4 μm or more and 11 μm or less because the toner triboelectric charge amount or image quality and image density are balanced. When the weight average particle diameter of the toner is 11 μm or less, it is possible to suppress a decrease in reproducibility of the minute dot image. On the other hand, when the weight average particle diameter of the toner is 4 μm or more, it is possible to suppress the occurrence of fogging, low density, and the like due to charging failure. As the binder resin for toner, for example, vinyl resins, polyester resins, polyurethane resins, epoxy resins, phenol resins, and the like can be used, and among these, vinyl resins and polyester resins are preferable. The charge control agent may be included (internally added) in the toner particles, or may be mixed with the toner particles (externally added). The charge control agent facilitates optimal charge amount control according to the development system. Examples of the positive charge control agent include the following. Modified products with nigrosine, triaminotriphenylmethane dyes and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate. These can be used alone or in combination of two or more. As the negative charge control agent, organometallic compounds and chelate compounds are effective. Examples thereof include aluminum acetylacetonate, iron (II) acetylacetonate, and 3,5-ditertiary butyl salicylate. In particular, acetylacetone metal complexes, monoazo metal complexes, naphthoic acid or salicylic acid metal complexes or salts are preferred. These can be used alone or in combination of two or more. Examples of the magnetic material which is an essential component in the magnetic toner include the following. Iron oxide-based metal oxides such as magnetite, maghemite and ferrite; magnetic metals such as Fe, Co and Ni. Alloys of these metals with metals such as Al, Co, Cu, Pb, Mg, Ni, Sn, Zn, Sb, Be, Bi, Cd, Ca, Mn, Se, Ti, W, V, and these blend. These magnetic materials can also serve as a colorant. These can be used alone or in combination of two or more.

  One or both of pigments and dyes can be used as the colorant.

  Examples of the release agent include the following. Aliphatic hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax and paraffin wax. Waxes based on fatty acid esters such as carnauba wax, Fischer-Tropsch wax, sazol wax and montan wax. Further, the toner is externally added with inorganic fine particles such as silica, titanium oxide, and alumina in order to improve environmental stability, charging stability, developability, fluidity, storage stability and cleaning properties, that is, a developer. It is preferable to exist in the vicinity of the surface. The addition amount of the inorganic fine particles is preferably 0.1% by mass to 5.0% by mass in the toner, and more preferably 0.5% by mass to 4.0% by mass. Further, various external additives may be used in combination. An external additive may be appropriately added to the toner. Examples of such external additives include lubricants such as tetrafluoroethylene, zinc stearate, polyvinylidene fluoride (in particular, polyvinylidene fluoride), cerium oxide, strontium titanate, strontium silicate and the like. be able to.

  In order to prepare the toner, first, a binder resin, a pigment or dye as a colorant, a release agent, and a magnetic material, a charge control agent, and other additives as necessary are mixed in a mixer such as a Henschel mixer or a ball mixer. Mix thoroughly. Next, this is melted using a heat kneader such as a heating roll, a kneader, or an extruder, and the release agent, pigment, dye, and magnetic substance are dispersed or dissolved while the resins are mutually compatible. The melt is cooled and solidified, and then pulverized and classified to obtain toner particles. Furthermore, a desired additive may be added as necessary, and mixed well by a mixer such as a Henschel mixer to obtain a developer (toner).

  When such a developer is used after being subjected to a spheroidizing treatment or a surface smoothing treatment by various methods, it is preferable because transferability is good. Examples of such a method include the following. In a device having a stirring blade or blade and a liner or casing, for example, when the developer is passed through a minute gap between the blade and the liner, the surface is smoothed or the developer is made spherical by mechanical force. Method. A method of spheroidizing by suspending toner in warm water, and a method of spheroidizing by exposing the toner to a hot air stream.

  Further, as a method for directly producing a spherical developer, there is a method in which a mixture containing a monomer as a developer binder resin as a main component is suspended in water and polymerized to obtain a toner. In general, first, a polymerizable monomer, a colorant, a polymerization initiator and, if necessary, a crosslinking agent, magnetic material, charge control agent, release agent, and other additives are uniformly dissolved or dispersed in a single amount. The body composition. Next, the monomer composition is dispersed in appropriate particles in a continuous layer containing a dispersion stabilizer, such as an aqueous phase, using an appropriate stirrer, and further subjected to a polymerization reaction to develop a toner having a desired particle size. It is a method of obtaining an agent.

  Hereinafter, the present invention will be described in more detail with reference to examples. First, methods for measuring various physical properties in Examples will be described.

<Developer carrier>
(A) Abundance ratio of C atoms and Si atoms (X-ray photoelectron spectroscopy analysis)
The abundance ratio of Si atoms in the resin layer was measured under the following conditions using an X-ray photoelectron spectrometer.
・ Measurement device: Quantum 2000 (trade name, manufactured by ULVAC-PHI Co., Ltd.)
・ X-ray source; Monochrome Al Kα
-Xray Setting; 100 μmφ (100 W (20 KV))
-Photoelectron extraction angle: 45 degrees-Neutralization conditions: Combination use of neutralization gun and ion gun-Analysis area: 300 x 1500 µm
・ Pass Energy; 11.75 eV
・ Step size: 0.05eV
Here, the abundance ratio of Si atoms uses peaks of C 1s (B.E. 280-295 eV), O 1s (B.E. 525-540 eV) and Si 2p (B.E. 95-113 eV), The atomic percentage of C atoms and Si atoms was determined by atomic percentage of Si 2p.

As the atomic% of C atoms (C ₀ ) and the atomic% of Si atoms (Si ₀ ) on the surface of the resin layer, the results of X-ray photoelectron spectroscopy analysis of the outermost surface of the resin layer were used. For the atomic% of C atoms (C ₁ ) and atomic% of Si atoms (Si ₁ ) at a depth of 1 μm from the resin layer surface, use the results of X-ray photoelectron spectroscopy analysis of the surface after sputtering in the depth direction of the resin layer. It was. Sputtering in the depth direction of the resin layer was performed using C ₆₀ ions, the sputtering conditions were an acceleration voltage of 4 kV, the raster size was 2 × 0.5 mm ² , and the depth was 1 μm.

And it was determined whether it contained more silicone oil in the resin layer surface vicinity by satisfying the following general formula (I):
Si ₁ / C ₁ <Si ₀ / C ₀ (I).

(A) Calculation of polyether modification rate B / A of silicone oil (NMR)
The developer carrying member was subjected to ultrasonic treatment for 10 minutes while being immersed in methanol. Silicone oil was obtained by evaporating methanol from the immersion liquid, and the polyether modification rate B / A was calculated by the following method using an FT NMR apparatus (trade name: JNM-EX400, manufactured by JEOL Ltd.). The measurement conditions are as follows.
-Resonance frequency: 399.65 MHz,
-Pulse width: 7.2 μs,
Observation frequency width: 7993.60 Hz
Data points; 32768,
・ Uptake time: 4.0993s,
Delay time: 2.9010 s
・ Total number of times: 16 times
Measurement temperature: room temperature (21 ° C. to 24 ° C.)
-Dilution solvent: deuterated chloroform,
Reference material: chloroform (residual peak in the solvent: 7.24 ppm).

From the obtained ¹ H-NMR spectrum, calculation was performed using the following formula (II):
B / A = (D + E) / C (II).

In addition, C in Formula (II) is a signal integral value of hydrogen of a methyl group in the vicinity of 0 ppm in the ¹ H-NMR spectrum (silicone oil main chain unit, equivalent to 6H). D is a signal integral value of hydrogen (polyethylene oxide unit, 4H equivalent) of a methylene group around 3.6 ppm in the ¹ H-NMR spectrum. E is a signal integrated value of hydrogen of a methyl group around 1.1 ppm (equivalent to polypropylene oxide unit, 3H) in ¹ H-NMR spectrum.

(C) Analysis method of acrylic resin The polymer structure of the acrylic resin was analyzed using a pyrolysis GC / MS device “Voyager” (trade name, manufactured by Thermo Electron Co., Ltd.) by scraping the resin layer of the developer carrier. Asked. Thermal decomposition temperature: 600 ° C., column: HP-1 (15 m × 0.25 mm × 0.25 μm), Inlet: 300 ° C., Split: 20.0, injection amount: 1.2 ml / min, temperature rise: 50 It performed on the conditions of (degreeC (4min) -300 degreeC (20 degreeC / min)).

(D) Volume resistance of resin layer The volume resistance of the resin layer is determined by forming a resin layer of 7 μm to 20 μm on a 100 μm thick PET sheet and applying the resistivity meter “Loresta AP” (trade name, manufactured by Mitsubishi Chemical). Measured. The measurement environment was 20 ° C. to 25 ° C., 50% RH to 60% RH.

(E) Arithmetic mean roughness Ra of the developer carrier surface
The arithmetic mean roughness Ra of the surface of the developer carrying member was measured using a surface roughness meter “Surf Coder SE-3500” (trade name, manufactured by Kosaka Laboratory Co., Ltd.) based on JIS B0601 (2001). As measurement conditions, a cut-off of 0.8 mm, an evaluation length of 4 mm, and a feed rate of 0.5 mm / s were measured for 3 points in the axial direction × 3 points in the circumferential direction = 9 points. The arithmetic average roughness Ra of the surface of the carrier was taken as the value.

(F) Volume average particle size of irregularity imparting particles As a measuring device for the particle size of irregularity imparting particles, a laser diffraction type particle size distribution meter (trade name: Coulter LS-230 type particle size distribution meter; manufactured by Beckman Coulter, Inc.) is used. It was. A small amount module was used for the measurement, and isopropyl alcohol (IPA) was used as the measurement solvent. First, the measurement system of the measuring apparatus was washed with IPA for about 5 minutes, and a background function was executed after washing. Next, about 10 mg of a measurement sample was added to 50 ml of IPA. Disperse the sample suspension for about 2 minutes with an ultrasonic disperser to obtain a sample solution, and then gradually add the sample solution into the measurement system of the measurement device. The PIDS on the screen of the device is 45%. The sample concentration in the measurement system was adjusted to be 55% to 55%. Thereafter, measurement was performed, and a volume average particle diameter calculated from the volume distribution was obtained.

(G) Resin layer film thickness For measuring the resin layer film thickness, a laser dimension measuring instrument (manufactured by Keyence Corporation; controller “LS-5500” (trade name)) that measures the outer diameter of the cylinder with laser light. A sensor head “LS-5040T” (trade name) was used. A sensor unit was separately fixed to an apparatus equipped with a developer carrier fixing jig and a developer carrier feeding mechanism, and the outer diameter of the developer carrier was measured. The measurement was carried out at 30 locations by dividing the developer carrier in the longitudinal direction into 30 parts, and further rotating the developer carrier 90 ° in the circumferential direction, followed by 30 locations, a total of 60 locations. The average value of the measured values obtained was taken as the outer diameter of the sample. The outer diameter of the substrate was measured before the resin layer was formed, the outer diameter was measured again after the resin layer was formed, and the difference was taken as the film thickness of the resin layer.

<Developer>
(H) Developer (magnetic toner) weight average particle diameter D4
The particle size distribution of the developer (magnetic toner) was measured using a particle size measuring device (trade name: Coulter Multisizer III; manufactured by Beckman Coulter, Inc.). As the electrolytic solution, an approximately 1% NaCl aqueous solution prepared using primary sodium chloride was used. In about 100 ml of the electrolyte, about 0.5 ml of alkylbenzene sulfonate was added as a dispersant, and about 5 mg of a measurement sample was further added to suspend the sample. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 minute, and the volume and the number distribution of the measurement sample are measured with the measuring device using a 100 μm aperture. Was calculated. From this result, the weight-based weight average particle diameter (D4) determined from the volume distribution was determined.

(K) Average circularity of developer The average circularity of the developer is used as a simple method for quantitatively expressing the shape of the particles. The measurement was performed using a flow type particle image measuring device “FPIA-2100” (trade name, manufactured by Sysmex Corporation) in an environment of 23 ° C. and 60% RH. Developers having a circle equivalent diameter of 0.60 μm to 400 μm were measured, and the individual circularity of the particles measured there was determined by the following (III). The average circularity of the sample is a value obtained by dividing the total circularity of particles having an equivalent circle diameter of 3 μm or more and 400 μm or less by the total number of particles.

Circularity = L0 / L (III)
In the equation, L0 is the circumference of a circle having the same projection area as the particle image, and L is the particle projection image when image processing is performed with an image processing resolution of 512 × 512 (pixels of 0.3 μm × 0.3 μm). Perimeter length.

  In “FPIA-2100” (trade name), after calculating the circularity of each particle, in calculating the average circularity, each particle has a circularity of 0.4 to 1.0 depending on the obtained circularity. The range is divided into 61 divided classes, and the average circularity is calculated using the center value and frequency of the dividing points. The error between the average circularity calculated by this calculation method and the average circularity calculated by a calculation formula using the sum of the circularity is very small and can be substantially ignored. In the present invention, for the purpose of shortening the calculation time and simplifying the calculation calculation formula, the calculation formula concept using the sum of the circularity of the developer is used, and the calculation method partially changed is used. Also good.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. Note that “parts” and “%” in the following formulations are “parts by mass” and “% by mass”, respectively, unless otherwise specified.

(1) Production of raw material for developer carrier <Silicone oil>
<< Production Example of Unmodified Silicone Oil a-1 >>
Octamethylcyclotetrasiloxane 100 parts by mass Pentamethyldisiloxane 10 parts by mass Concentrated sulfuric acid 0.1 part by mass The above mixture was placed in a container and allowed to react for 10 hours while maintaining at 30 ° C under normal pressure. After completion of the reaction, neutralization was performed to obtain unmodified silicone oil a-1.

<< Production Example of Unmodified Silicone Oils a-2 to a-10 >>
Except for changing the materials to be mixed as shown in Table 1, unmodified silicone oils a-2 to a-10 were produced in the same manner as in the production example of unmodified silicone oil a-1.

<Polyalkylene glycol>
The following were used as polyalkylene glycols used in the production of the modified silicone oil.
B-1: Polypropylene glycol-allyl ether (trade name: Unisafe PKA-5014; manufactured by NOF Corporation)
B-2: Methoxy-polyethylene glycol-allyl ether (trade name: UNIOX PKA-5006; manufactured by NOF Corporation)
B-3: Polyethylene glycol-polypropylene glycol-allyl ether (random type) (trade name: Unisafe PKA-5011; manufactured by NOF Corporation)
B-4: Polyethylene glycol-allyl ether (trade name: UNIOX PKA5003; manufactured by NOF Corporation)
B-5: Polyethylene glycol (trade name: PEG # 300; manufactured by NOF Corporation)
<< Silicone oil c-1 >>
The silicone oil c-1 was the unmodified silicone oil a-1.

<< Production Example of Modified Silicone Oil c-2 >>
Unmodified silicone oil a-2 100 parts by mass Polyalkylene glycol b-4 45 parts by mass Toluene 200 parts by mass To the above mixture, a platinum chloride salt was added as a catalyst, stirred at a reaction temperature of 90 ° C., and allowed to react for 5 hours. The platinum chloride salt was weighed and added so as to be 10 ppm with respect to polyalkylene glycol in terms of platinum element. After completion of the reaction, purification was performed to obtain a side chain polyethyl ether-modified silicone oil c-2. Table 3 shows the polyether modification rate B / A and modification type of the obtained modified silicone oil.

<< Production Examples of Modified Silicone Oils c-3 and c-5 to c-13 >>
Modified silicone oils c-3 and c-5 to c-13 were produced in the same manner as in the production example of silicone oil c-1, except that the materials to be mixed were changed as shown in Table 2. Table 3 shows the polyether modification rate B / A and modification type of the obtained modified silicone oil.

<< Production Example of Modified Silicone Oil c-4 >>
By dehydrogenating 100 parts by mass of polyethylene glycol b-5 and 90 parts by mass of unmodified silicone oil a-4, modified silicone oil c-4 was obtained. Table 3 shows the polyether modification rate B / A and modification type of the obtained modified silicone oil.

<< Modified silicone oil c-14 to c-16 >>
Silicone oils c-14 to c-16 were as follows.
C-14: Side chain amino-modified silicone oil (trade name: KF-868; manufactured by Shin-Etsu Chemical Co., Ltd.)
C-15: Amino-modified silicone oil at both ends (trade name: X-22-161A; manufactured by Shin-Etsu Chemical Co., Ltd.)
C-16: Both-ends epoxy-modified silicone oil (trade name: X-22-163A; manufactured by Shin-Etsu Chemical Co., Ltd.)

<Acrylic resin>
<< Production Example of Acrylic Resin Solution d-1 >>
In a four-necked separable flask equipped with a stirrer, a cooler, a thermometer, a nitrogen introduction tube and a dropping funnel, the following materials were mixed and stirred until the system became uniform.
-44.9 parts by mass of dimethylaminoethyl methacrylate (monomer e-1),
-Octyl bromide (quaternizing agent) 55.1 parts by mass,
-50 mass parts of ethanol.

  The temperature was raised to 70 ° C. while continuing the stirring, and the monomer e-1 was quaternized by stirring for 5 hours to obtain (2-methacryloyloxyethyl) octyldimethylammonium bromide which is a quaternary ammonium base-containing monomer. It was. After cooling the obtained reaction solution, 29.4 parts by mass of lauryl acrylate (monomer e-2) as a copolymer component, 50 parts by mass of ethanol as a solvent, and azobisisobutyronitrile (AIBN) 1 as a polymerization initiator 0.0 part by mass was charged and stirred until the system was uniform. While continuing the stirring, the temperature in the reaction system was raised to 70 ° C., and the portion charged in the dropping funnel was added over 1 hour. After completion of the dropwise addition, the reaction was further continued for 5 hours under reflux with introduction of nitrogen, and further 0.2 parts by mass of AIBN was added, followed by reaction for 1 hour. Further, this solution was diluted with ethanol to obtain an acrylic resin solution d-1 having a solid content of 40% by mass. As a result of analyzing the obtained acrylic resin solution, it was found to be a copolymer of units of the following chemical formula (11) and chemical formula (12).

<< Production Example of Acrylic Resin Solution d-2 to 32 >>
Except having changed the copolymerization component as shown in Table 4, it carried out similarly to the manufacture example of the acrylic resin solution d-1, and obtained acrylic resin solution d-2-d-32. In addition, acrylic resin solution d-7, d-16, and d-30 performed ion exchange from bromine ion to p-toluenesulfonic acid ion by ion exchange resin after the production | generation of an acrylic resin solution. Table 5 shows the structure of the obtained acrylic resin.

<Binder resin>
The following resins were used as the binder resin used for the developer carrier.
F-1: Resol type phenol resin solution containing 40% by mass of methanol (trade name: J-325; manufactured by Dainippon Ink Co., Ltd.)
F-2: A blend of polyol (trade name: Nipponporan 5037; manufactured by Nippon Polyurethane Industry) and a curing agent (trade name: Coronate L; manufactured by Nippon Polyurethane Industry) in a ratio of 10: 1.
-F-3: What mix | blended 8: 2 the epoxy resin (Brand name: 1001B80; Japan Epoxy Resin Co., Ltd.) and the hardening | curing agent (Brand name: SL11; Japan Epoxy Resin Co., Ltd.).
F-4: Thermoplastic acrylic resin (trade name: A-430-60; manufactured by Dainippon Ink & Chemicals, Inc.).

<Conductive agent>
As the conductive agent used for the developer carrying member, the following was used.
Conductive agent g-1: Toka Black # 5500 (trade name, manufactured by Tokai Carbon Co., Ltd.)
Conductive agent g-2: CSP-E (trade name, manufactured by Nippon Graphite Co., Ltd .; primary average particle size = 4.5 μm).

<Roughness imparting particles>
Nika beads ICB-0520 (trade name, manufactured by Nippon Carbon Co., Ltd .; volume average particle size = 6.2 μm) was used as the irregularity imparting particles.

(2) Production of Developer << Production Example of Developer h-1 >>
[Production of hybrid resin]
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane
7.0 mol
Polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane
3.0 mol
Terephthalic acid 3.0mol
Trimellitic anhydride 1.9 mol
Fumaric acid 5.0 mol
Dibutyltin oxide 0.2g
The above material was put into a 4-liter 4-neck flask made of glass, and a thermometer, a stirring rod, a condenser and a nitrogen introduction tube were attached, and placed in a mantle heater.
Styrene 1.9 mol
2-Ethylhexyl acrylate 0.21 mol
Fumaric acid 0.15 mol
α-Methylstyrene dimer 0.03 mol
Dicumyl peroxide 0.05 mol
The said material was put into the dropping funnel as a vinyl polymer raw material.

Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the vinyl polymer raw material was dropped from the previous dropping funnel over 4 hours while stirring at a temperature of 145 ° C. Next, the temperature was raised to 200 ° C. and reacted for 4 hours to obtain a hybrid resin.
100 parts magnetic iron oxide (average particle size: 0.18 μm, Hc: 9.6 kA / m, σs: 81 Am ² / kg, σr: 13 Am ² / kg) 75 parts monoazo iron complex “T-77” ( Trade name, manufactured by Hodogaya Chemical Co., Ltd.) 2 parts low molecular weight ethylene-propylene copolymer (manufactured by Sanyo Chemical Co., Ltd., trade name: Viscol 550-P) 5 parts Biaxial Ext. Heated to 130 ° C. After melt-kneading with a loader, the melt-kneaded mixture was cooled and solidified. The cooled and solidified mixture is coarsely pulverized with a hammer mill, and the resulting coarsely pulverized product is finely pulverized with a turbo mill (manufactured by Turbo Kogyo Co., Ltd.) and then classified with an air classifier to obtain a magnetic material having a weight average particle diameter of 5.5 μm. A toner was obtained.

To 100 parts of this magnetic toner, 1.0 part of hydrophobic silica fine powder (BET 180 m ^{2 /} g) is externally added with a Henschel mixer “FM-75 type” (trade name, manufactured by Mitsui Miike Chemical Co., Ltd.). Thus, developer h-1 having a circularity of 0.935 was obtained.

(3) Production of developer carrier (Example 1)
<Manufacture of developer carrier i-1>
Developer carrier i-1 was produced by the following method. First, the following materials were mixed and treated with a horizontal sand mill (filling ratio of zirconia beads having a diameter of 1.0 mm of 85%) to obtain a coating liquid j-1.
Silicone oil c-3 5 parts by mass Acrylic resin solution d-14 62.5 parts by mass (solid content 25 parts by mass)
Resin f-1 416.7 parts by mass (solid content 250 parts by mass)
Conductive agent g-1 10 parts by weight Conductive agent g-2 90 parts by weight Concavity and convexity imparting particles 15 parts by weight Methanol 250 parts by weight As a base, an aluminum cylindrical tube having an outer diameter of 20 mm (Ra = 0.4 μm; reference length (lr) = 4 mm) was prepared. After masking 6 mm at both ends of the substrate, the substrate was placed so that its axis was parallel to the vertical. And the said base | substrate was rotated at 1000 rpm, the coating liquid j-1 was apply | coated while lowering | hanging an air spray gun at 30 mm / sec, and the coating film was formed so that the thickness after hardening might be set to 12 micrometers. Then, it heated for 30 minutes in a 150 degreeC hot-air drying furnace, the coating film was hardened, and the developer carrier i-1 was obtained. As a result of measuring the abundance ratio of Si atoms in the obtained developer carrier, the abundance ratio of Si atoms is higher on the resin layer surface (16.0 atom%) than inside the resin layer (1.8 atom%). I understood.

<Formation of electrophotographic image forming apparatus and image evaluation using the same>
A magnet roller was inserted into the obtained developer carrying member i-1, flanges were attached to both ends, and the developer was mounted as a developing roller of a developing device of an electrophotographic image forming apparatus (trade name: iR3045; manufactured by Canon Inc.). The gap between the magnetic doctor blade and the developer carrier i-1 was 210 μm.

Further, the developer h-1 was added as a developer to the electrophotographic image forming apparatus, and the following image evaluation was performed. For image evaluation, A4 office planner paper (trade name, manufactured by Canon Sales; 64 g / m ² ) was used. The results are shown in Tables 8 and 9.

(1) Blotch The electrophotographic image forming apparatus was rotated for 10 minutes, and then a halftone image was output and the toner coat layer on the developer carrying member was observed. Furthermore, 20-minute idling (total 30-min idling) was performed, and then the same evaluation as 10-min idling was performed. Evaluation was carried out in a normal temperature and low humidity environment (23 ° C., 5% RH; N / L) and a normal temperature and normal humidity environment (23 ° C., 50% RH; N / N).
A: There is no disturbance in the toner coat layer on the surface of the developer carrying member after idling for 30 minutes.
B: Although the toner coat layer on the surface of the developer carrying member after idling for 30 minutes is slightly disturbed, no blotch (uneven fog or image disorder) can be confirmed on the halftone image.
C: Although the blotch cannot be confirmed in the halftone image after the 10-minute idling, a slight blotch can be confirmed in the halftone image after the idling after 30 min.
D: A slight blotch can be confirmed in the halftone image after 10 minutes of idling.
E: A clear blotch can be confirmed in the halftone image after spinning for 10 minutes.

(2) Image Density An image printing test was conducted for a continuous copy of a character image with a printing ratio of 3% up to 1 million sheets in A4 horizontal feed. The image evaluation was performed in a high-temperature and high-humidity environment (30 ° C., 80% RH; H / H) and a normal temperature and normal humidity environment (23 ° C., 50% RH; N / N).

In the image output test, a solid image was output, the density was measured at five points, the average value was taken as the image density, and the relative density with respect to the white background image with a document density of 0.00 was measured. From the result, the following criteria were evaluated. The image density was “Macbeth reflection densitometer RD918” (trade name, manufactured by Macbeth Co.).
A: 1.35 or more.
B: 1.25 or more and less than 1.35.
C: 1.15 or more and less than 1.25.
D: 1.00 or more and less than 1.15.
E: Less than 1.00.

(3) Amount of frictional charge of toner on developer carrier (Q / S)
The toner carried on the developer carrying member was sucked and collected by a metal cylindrical tube and a cylindrical filter, and the charge amount Q stored in the condenser through the metal cylindrical tube and the area S where the toner was sucked were measured. From these values, the charge amount Q / S per unit area (10 · μC / m ² ) was calculated.

  Evaluation is performed at normal temperature and low humidity environment (23 ° C., 5% RH; N / L), normal temperature and normal humidity environment (23 ° C., 50% RH; N / N), high temperature and high humidity environment (30 ° C., 80% RH; H / H). The Q / S after 1 million sheets was evaluated after outputting the evaluation image after 1 million sheets in the image density evaluation.

(Examples 2 to 61, Comparative Examples 1 to 10)
Developer carriers i-2 to i-61 and j-62 to 71 were produced in the same manner as in Example 1 except that the materials used were changed as shown in Tables 6 and 7. And it evaluated similarly to Example 1 using the improved image development apparatus incorporating the obtained developing agent carrier. The results are shown in Tables 8 and 9.

Further, whether or not the silicone oil is unevenly distributed on the surface side in the resin layer of each developer carrier was confirmed as follows. That is, whether or not (Si ₁ / C ₁ ) <(Si ₀ / C ₀ ) was satisfied was confirmed. The abundance ratios of Si atoms and C atoms on the surface of the resin layer measured by X-ray photoelectron spectroscopy are Si ₀ (atomic%) and C ₀ (atomic%), respectively, and a depth of 1 μm from the surface of the resin layer. The abundance ratio of Si atoms and C atoms in is Si ₁ (atomic%) and C ₁ (atomic%). As a result, i-1 to i-61, j-62 to j-63, and j-66 to j-71 confirmed that the silicone oil was unevenly distributed on the surface side of the resin layer.

  As can be seen from Tables 8 and 9, good results were obtained in the developing devices using the developer carriers i-1 to i-61 obtained in Examples 1 to 61.

  Regarding Comparative Example 1, since the silicone oil used for developer carrier j-62 does not have an amino group and a polyether group, the polarity difference from the acrylic resin is small. Therefore, although the silicone oil is unevenly distributed on the surface side of the resin layer, the amount thereof is small as compared with the developer carrier according to the example, and the excessive charging of the fresh developer cannot be sufficiently suppressed. It is presumed that the evaluation rank of the blotch in the “N / L” environment of Comparative Example 1 is “D” for this reason. The “N / L” environment is an environment in which excessive charging of the developer and uneven charging are more likely to occur.

  Regarding Comparative Example 2, the silicone oil used for developer carrier j-63 is epoxy-modified at both ends, and is not compatible with the binder resin. Therefore, the surface of the resin layer has a sea-island structure. The reason why the evaluation rank of the blotch in the “N / L” environment of Comparative Example 2 is “E” is presumed that the developer is non-uniformly charged due to the sea-island structure.

  Regarding Comparative Example 3, silicone oil is not used for the developer carrier j-64. Therefore, the developer was excessively charged, and the evaluation rank of the blotch in the “N / L” environment was “E”.

  Regarding Comparative Examples 4 and 5, since the developer carriers j-65 and j-66 do not use the acrylic resin according to the present invention, the charging performance is not sufficient. Originally, even in an “N / L” environment where the developer is easily charged, the charge amount (Q / S) is estimated to be as low as “6.7” or “6.1” for this reason. The

  Regarding Comparative Example 6, for the developer carrier j-67, a thermoplastic acrylic resin was used as the binder resin for the resin layer. For this reason, it was worn out by long-term use, and the image density after 1 million sheets in the “H / H” environment greatly changed from the initial stage due to the change in the surface shape of the developer carrier.

  Regarding Comparative Examples 7 to 9, in the developer carriers j-68 to j-70, the acrylic resin in the resin layer does not have the unit represented by the chemical formula (2) according to the present invention. That is, the carbon number of the alkyl group corresponding to “R8” in the chemical formula (2) according to the present invention is short. Therefore, the dispersibility with respect to the binder resin of an acrylic resin is low. Therefore, an acrylic resin having a unit having a quaternary ammonium base that is excellent in the charge imparting ability of the developer is localized in the resin layer, and the ability to impart friction to the developer is not uniform. In Comparative Examples 7 to 9, it is presumed that the evaluation rank of the blotch in the “N / L” environment is “D” due to the unevenness of the charge imparting ability of the developer carrier.

  Regarding Comparative Example 10, in the developer carrying member j-71, the acrylic resin in the resin layer has as large as 22 carbon atoms in the alkyl group corresponding to “R11” in the chemical formula (3) according to the present invention. Therefore, an acrylic resin having a unit having a quaternary ammonium base that is excellent in the charge imparting ability of the developer is localized in the resin layer, and the ability to impart friction to the developer is not uniform. In Comparative Example 10, it is estimated that the evaluation rank of the blotch in the “N / L” environment is “D” due to the unevenness of the charge imparting ability of the developer carrier.

101 201 301 Resin layer 102 202 302 Substrate 103 203 303 Developing sleeve 104 204 Magnet roller 105 205 Developer carrier 106 206 306 Photosensitive drum (electrostatic latent image carrier)
107 Magnetic blade (developer layer regulating member)
109 209 309 Development container 215 315 Elastic blade (developer layer regulating member)
317 Non-magnetic one-component developer

Claims (3)

A resin layer as a substrate and a surface layer, the resin layer being a thermosetting resin as a binder resin, a silicone oil represented by the following chemical formula (1), a unit represented by the following chemical formula (2), and And an acrylic resin having a unit represented by the following chemical formula (3),
The developer carrying member, wherein the silicone oil is unevenly distributed on the surface side of the resin layer:

[In the chemical formula (1), at least one of R 1 to R 6 is an amino group or a polyether group, and the other R 1 to R 6 are independently an alkyl group having 1 to 4 carbon atoms. m is an integer of 5 or more. ];

[In the chemical formula (2), R7 is a hydrogen atom or a methyl group, and R8 is an alkyl group having 8 to 18 carbon atoms. ];

[In the chemical formula (3), R9 is a hydrogen atom or a methyl group, R10 is an alkylene group having 1 to 4 carbon atoms, R11 to R13 are independently an alkyl group having 1 to 18 carbon atoms, and X ⁻ is Anion. ]. The developer carrier according to claim 1, wherein the silicone oil is represented by the chemical formula (5):

[In the chemical formula (5), one or both of R15 and R16 is the following chemical formula (6), R15 and R16 which are not the following chemical formula (6) are alkyl groups having 1 to 4 carbon atoms, and R14 and R17 to Each R19 is independently an alkyl group having 1 to 4 carbon atoms, and m is an integer of 5 or more];

[In the chemical formula (6), R20 is any one of O, C ₂ H ₄ O and C ₃ H ₆ O, R 21 is an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, and q and r are each It is independently an integer of 0 or more, at least one of q and r is an integer of 1 or more, and n is an integer of 1 or more.   A developing device comprising: a negatively chargeable developer having toner particles; a container containing the developer; and the developer carrying member according to claim 1.

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