JP2003043810A - Polymer elastic composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To respond to the recent increase in the output rate in a electrophotographic device and to improve the copy efficiency (efficiency in the output printing or the like) of the device. SOLUTION: A material prepared by kneading and crosslinking at least a polar polymer, a crosslinking agent and a triboelectrification controlling agent is used for the elastic conductive body 8b of a regulating member 3c so that a developing roller 3a is electrified to -200 V or lower in the triboelectrification process and that a toner can be electrified to a sufficiently high positive potential. As for the triboelectrification controlling agent, a material having >=0.1 Hammett substitution constant σp of electron withdrawing groups is used and added by 0.5 to 2 parts by weight. As for the polar polymer, for example, an urethane polymer, silicone polymer, nitrile butadiene rubber or the like is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polymer elastic body composition mainly used in laser printers, copying machines, facsimiles and other electrophotographic apparatuses, and more particularly to a polymer elastic body composition used as a regulating member. is there.

[0002]

2. Description of the Related Art A dry electrophotographic apparatus using a dry developing method (Carlson method) is often used in a copying machine or an external output device (for example, a laser printer) of a computer, and the developing system is mainly used for a charging process and a latent image. It consists of a baking process, a developing process, a transfer process, and a fixing process, and is composed of developing system, transfer system, fixing system, and photosensitive system parts which are generally called engine system parts.

The above-mentioned developing method is a two-component contact developing method, a two-component non-contact developing method, a one-component contact developing method, depending on the contact state between the photosensitive system and the developing system and the toner (developer) component used for the development. Classified as a one-component non-contact development method. In recent years, the one-component contact developing method using a non-magnetic toner has been widely used in consideration of the simplification of the structure of the electrophotographic apparatus and the developability for colorization. In the developing system, the parts include, for example, a developing roller (developer carrying member), a developer conveying roller, a developer regulating blade (developer layer thickness regulating material;
Hereinafter, the term "regulating member" is used.

FIG. 4 is a schematic block diagram of an electrophotographic apparatus using a general one-component contact developing method. In FIG. 4, reference numeral 1 denotes a photosensitive drum having a conductive support drum body provided with a photoelectric layer on the surface thereof, and is mounted rotatably in the direction of arrow C in FIG. Around the photosensitive drum 1, along the circumferential direction thereof, a charging roller 2, a developing device 3, a transfer roller (transfer device) 4, a cleaning device 5 (for example, in the case of the simultaneous development cleaning type, it may be omitted).
Are placed.

The charging roller 2 is the photosensitive drum 1
The outer peripheral surface of the charging roller 2 is uniformly charged (charged to a negative potential).
The surface of the photosensitive drum 1 is charged by bringing the photosensitive drum 1 into contact with the photosensitive drum 1. Then, the outer peripheral surface of the photoconductor drum 1 is irradiated with light in a desired pattern from a latent image forming device (not shown), and an electrostatic latent image is formed on a portion irradiated with the light (in the case of reversal development). ), Or an electrostatic latent image is formed (in the case of regular development) on a portion not irradiated with the light.

The developing device 3 comprises a developing roller 3a, a developer carrying roller 3b and a regulating member 3c, and the toner filled in the developing device 3 is attached to the electrostatic latent image on the photosensitive drum 1. This is for developing. By the developing device 3, the developing roller 3a and the photosensitive drum 1 are arranged so that the toner is attached only to the light irradiation portion in the case of reversal development and the toner is attached only to the light non-irradiation portion in the case of regular development. A bias voltage is applied between and.

The developing roller 3a is arranged so as to be in partial contact with the outer peripheral surface of the photosensitive drum 1, and rotates in the direction of arrow D shown in the figure, which is opposite to the rotational direction C of the photosensitive drum 1. As the developing roller 3a, for example, one in which the outer peripheral surface of a metal shaft is covered with a polymeric elastic body composition (hereinafter referred to as an elastic body) made of a rubber material such as urethane polymer is known. The developer carrying roller 3b is brought into contact with the outer peripheral surface of the developing roller 3a, and the developing roller 3b
The toner is supplied to the outer peripheral surface of the developing roller 3a by rotating in the direction of arrow E, which is the same as the rotating direction of a.

The regulating member 3c is the developing roller 3a.
For example, a band shape is formed so as to contact along the axial direction of. The restricting member 3c is formed by adhering an elastic body 8b containing a urethane polymer or the like as a main component to a holder 8a such as a metal leaf spring (iron plate). The elastic body 8
b (for example, a corner portion of the elastic body 8b) is connected to the developing roller 3a.
By contacting the outer peripheral surface of the with a predetermined pressure,
When the developing roller 3a rotates, the toner supplied to the outer peripheral surface of the developing roller 3a is regulated, and frictional electrification occurs between the elastic body 8b (and the developing roller 3a) and the toner. Positive electric charge (triboelectric charge) is injected (toner is positively charged).

The transfer roller 4 is for copying the toner image on the outer peripheral surface of the photosensitive drum 1 formed by the developing device 3 onto the transfer paper 6. During the copying, the transfer paper 6 is fed and discharged in the direction of the white arrow in the figure through the paper feed roller 7a and the paper discharge roller 7b, and the toner image copied on the transfer paper 6 is fixed by the fixing roller. The image is fixed by 7c, and desired output printing is performed.

[0010]

The elastic body used for the regulating member of the electrophotographic apparatus as shown in FIG.
As shown in FIGS. 6 to 6, it is necessary to prevent bleed-out (phenomenon in which the plasticizer oozes out) and to secure sufficient conductivity, flexibility, chargeability, toner releasability, and abrasion resistance.

(Condition 1; Bleed-out) A plasticizer is added to the elastic body used for the regulating member for the purpose of improving molding processability and decreasing hardness, but prevents the plasticizer from bleeding out, that is, plasticizing. It is necessary to prevent the agent from seeping out from the elastic body. When this bleed-out happens,
Toner is fused to the surface of the elastic body by the exuded plasticizer (hereinafter referred to as toner fusion), and printing defects such as abnormal streaks and print defects occur on the copy paper to be printed.

(Condition 2; conductivity and volume resistivity)
An elastic body having conductivity (hereinafter referred to as an elastic conductor) in consideration of charge injection due to triboelectrification, in the regulating member.
Is used, and the volume resistivity value of the elastic conductor is about 10
It is preferable to set in the range of ⁴ Ω · cm to 10 ¹¹ Ω · cm. If this volume resistivity becomes too high,
Since the flow of electrons in the elastic conductor slows down, the toner moves to the photosensitive drum before the charge is injected, and the charge due to frictional charging is accumulated in the elastic conductor. (And the developing roller) may cause abnormal discharge, resulting in defective printing. When the volume resistivity value is too low,
The electric charge due to the above-mentioned frictional charge easily leaks through the regulating member, and the electric charge cannot be sufficiently injected into the toner, which causes printing failure.

(Condition 3; Flexibility) The electric field at the time of performing charge injection by triboelectrification can be expressed by the electric field strength, that is, the electric flux density per unit area. Since the toner moves at a constant speed in the developing device, it is effective to increase the electric field area in order to favorably perform the triboelectric charging.
Therefore, the elastic conductor is provided with sufficient flexibility so that the tip end portion of the elastic conductor is crushed at the portion in contact with the developing roller to increase the contact area between the elastic conductor and the developing roller. There is a need.

(Condition 4; Charging property) When two members having different physical properties (for example, a regulating member and a toner) are brought into contact with each other and rubbed against each other, the two members are locally charged and polarized according to van der Waals polarization. (Molecular dielectric polarization; electrification polarization at positive and negative potentials; forming dipole moment), and when the contact part of one member is charged and polarized at negative potential, induced polarization at the contact part of the other member Is excited to be charged and polarized to a positive potential. That is, in order to charge the toner to the positive potential, it is necessary to set the elastic conductor of the regulating member to be negatively charged and polarized by frictional charging. If this charging (the degree of charging to a negative potential) is insufficient, the fog density may increase and printing defects may occur.

(Condition 5: Toner releasability) When the elastic conductor of the regulating member has low releasability from the toner, the toner stays on the surface of the elastic conductor and fuses with the toner (blocking; aggregation of toners). At the same time, the surface of the fused material is excessively charged and a charge blocking body is formed. This charge blocking member makes it difficult to uniformly form a toner layer on the developing roller (for example, streak marks are formed), and white streaks are formed on the transfer paper during copying or a portion having a relatively low density. May be formed, resulting in defective printing. Therefore, it is necessary to ensure sufficient releasability in the elastic conductor of the regulating member.

(Condition 6; abrasion resistance) Since the elastic conductor of the regulating member rubs against the toner and the developing roller, abrasion and chipping progress with repeated copying, and the contact state with the developing roller becomes unsatisfactory. If the toner becomes uniform, the toner cannot be regulated or charged uniformly, which may cause printing failure. Therefore, the elastic conductor used for the regulation member needs to have wear resistance.

Considering the above conditions 1 to 6, for example, a regulating member formed by laminating a triboelectrification sheet made of methyl methacrylate / methacrylic acid copolymer on an elastic body (see Japanese Patent Laid-Open No. 2000-35715). However, production efficiency is low and cost is high because many steps are required to form the regulating member.

Also known is a regulating member (see Japanese Patent Application Laid-Open No. 11-352774) in which a quaternary ammonium salt is added to an elastic conductor to charge it to a negative potential during frictional charging. Considering the demand for higher performance (improvement of copying efficiency) in an electrophotographic apparatus, its charging property is insufficient. The reason why the above-mentioned quaternary ammonium salt charges the regulating member to a negative potential during triboelectric charging has not been sufficiently clarified.

The present invention has been made based on the above-mentioned problems, and prevents bleed-out and secures conductivity, flexibility, toner releasability, and abrasion resistance, and at the same time imparts sufficient chargeability. To provide a molecular elastic composition.

[0020]

In order to solve the above-mentioned problems, the present invention according to claim 1 regulates a one-component developer in a developing device on a developing roller, and In a polymeric elastic composition for triboelectrifying a one-component developer, at least a polymer, a cross-linking agent (cross-linking aid, vulcanizing agent) and a triboelectrification adjuster are kneaded and cross-linked, and the potential due to the triboelectrification is It is characterized by being −200 V or less.

The invention according to claim 2 is characterized in that, in the invention according to claim 1, the frictional charge control agent has an electron-withdrawing group having a Hammett substituent constant σp of 0.1 or more.

According to a third aspect of the present invention, in the invention according to the first or second aspect, the amount of the frictional charge control agent added is 0.5 to 2 parts by weight.

The invention according to claim 4 is characterized in that, in the invention according to any one of claims 1 to 3, the polymer is any one of urethane polymer, silicone polymer and nitrile butadiene rubber.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a polymer elastic material composition according to an embodiment of the present invention will be described with reference to the drawings.

Charging polarization due to van der Waals polarization is caused by the + I effect and −I effect of σ bond and the + R effect and −R effect of π bond mainly due to electron withdrawing property. The electron withdrawing property is the Hammett substituent constant σp (YPHAMMET “Physical Organ” based on the benzene ring coordination property).
ic Chemistry "Mc-GRAW-Hill (1940)) is known to be able to quantify.

Therefore, in the first to third embodiments of the present invention, various polymers, cross-linking agents, plasticizers and the like are used, and frictional charge control agents having various electron-withdrawing groups having different Hammett substituent constants σp are used. To make an elastic conductor,
By examining various characteristics of those elastic conductors, bleed out is prevented in the elastic conductors,
While ensuring sufficient conductivity, flexibility, toner releasability, and abrasion resistance, the elastic conductor is charged to a negative potential so that the toner is charged to a positive potential. This is to improve the efficiency of printing, etc.).

(First Embodiment of the Present Embodiment) In the first embodiment of the present embodiment, elastic electric conductors are prepared by using various frictional charge control agents, and the potentials of the elastic electric conductors after frictional charging (hereinafter, frictional charging) are prepared. (Referred to as electric potential), volume resistivity, rubber hardness, toner fusing property, and bleeding property were examined to study a triboelectrification control agent suitable for an elastic conductor in a regulating member of an electrophotographic apparatus.

First, in the composition shown in Table 1 below, a urethane polymer (millable polyester urethane) as a polymer (base polymer), a fatty acid metal salt as a processing aid, various conductive agents (acetylene black, conductive carbon black), and crosslinking. Cross-linking agents (trimethylolpropane trimethacrylate) and vulcanizing agents (organic peroxides) as agents, and various triboelectrification regulators (dimethyllaurylamine, methacryloyl ammonium salts) having electron-withdrawing groups with different Hammett substituent constants σp, respectively. , Sorbitan alkyl ester, polyamide, sodium di-2-ethylhexyl sulfosuccinate, sodium decylbenzene sulfonate, palmitic acid, perfluorooctyl sulfonate, paratoluene sulfonyl chloride, paranitrotoluene) By kneading the respective materials, kneaded materials P1 to P4 (the Hammett substituent constant of the electron withdrawing group is "0" or less) and S1 to S6 (Hammett substituent constant of the electron withdrawing group is "0.31" or more) are obtained. It was made. The trade names of the materials shown in Table 1 below are shown in Table 2 below.

[0029]

[Table 1]

[0030]

[Table 2]

Next, each of the kneaded products P1 to P1 shown in Table 1 above.
P4, S1-S6 are cross-linked to form a rectangular flat plate (20 mm x 2
0 mm x 2 mm) to obtain elastic conductors,
For these elastic conductors, the volume specific resistance value (Ω · cm) according to JIS K6911 and the rubber hardness (JIS-A) according to K6251 were measured. Further, in each of the elastic conductors described above, chargeability (friction charge potential) is obtained by the method shown in the explanatory views (details will be described later) of FIGS.
The toner fusing property and bleeding property were examined.

1A, 1B and 1C are explanatory views showing a method of measuring the triboelectric charge potential. First, as shown in FIG. 1A, a surface electrometer (Model 344 manufactured by Trek, Inc. (measurement error ± 1
0V)) glass rod connected to 11 (diameter φ8mm) 1
The tip of 2 is arranged at a distance of 5 mm from the elastic conductor 13, and the potential detected by the surface electrometer 11 is reset to "0V". Thereafter, as shown in FIG. 1B, the tip of the glass rod 12 is brought into contact with the surface of the elastic conductor 13 by applying a load of about 1.96N to 2.94N, and The operation of sliding back and forth by a distance of 15 cm in the direction of the white arrow inside is repeated 3 times.

Then, as shown in FIG. 1C, the tip portion of the glass rod 12 is arranged at a distance of 5 mm from the elastic conductor 13, and then the triboelectric potential of the glass rod 12 is detected by the surface electrometer 11. If the detected triboelectric potential is a positive value, it can be considered that the elastic conductor 13 is charged to a negative potential. In addition, in Table 3 (and Tables 4, 7, and 8) below, the triboelectric charge potential of the glass rod 12 is shown.

FIG. 2 is an explanatory view showing a method for measuring the toner fusibility. As shown in FIG. 2, first, 100 mg was applied between the elastic conductors 21a and 21b using the same kneaded material.
Toner (styrene-acrylic toner (+ charged toner)) 22 of No. 22 is intervened with a uniform thickness. Next, a load of 500 g is applied between the elastic conductors 21a and 21b.
Pressure is applied by the weight 23 and left for 72 hours in an atmosphere of 40 ° C. × 90% RH.

Then, the elastic conductors 21a and 21b are formed.
Are separated from each other to separate the toner 22 from the air (0.05MP
a) to remove the elastic conductor 21.
The amount (weight) of the toner remaining on the surfaces of a and 21b is measured. It can be considered that the smaller the amount of the remaining toner is, the less the toner fusion in the elastic conductor occurs.

FIG. 3 is an explanatory view showing a method of measuring bleeding property. The same components as those shown in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted. As shown in FIG. 3, first, a rectangular (30 mm × 30 mm) plain paper 31 is interposed between the elastic conductors 21a and 21b.
The weight of the plain paper is G ₀ . Next, the weight 23
Then, a pressure is applied between the elastic conductors 21a and 21b, and it is left for 72 hours in an atmosphere of a temperature of 80 ° C.

Then, the elastic conductors 21a and 21b described above are used.
, And the weight of the plain paper 31 (G
₁ ) is measured, and the weight difference from the weight G ₀ is calculated. It can be considered that the smaller the difference in weight, the less likely bleed-out occurs in the elastic conductors 21a and 21b. When the bleed out occurs, the plasticizer or the like adheres to the plain paper 31 and the weight difference becomes large.

Table 3 below shows the results of the triboelectrification potential, volume resistivity, rubber hardness, toner fusion property and bleeding property. In addition, in Table 3 (and Table 7 described later), the symbol “◯” indicates that no toner fusion or bleeding was observed.
The symbol “x” indicates that toner fusion and bleeding were observed.

[0039]

[Table 3]

As shown in Table 3, a kneaded product using a triboelectric charge controlling agent (dimethyllaurylamine, methacryloyl ammonium salt, sorbitan alkyl ester) having a Hammett substituent constant of the electron-withdrawing group of less than "-0.1" P
With the elastic conductors 1 to P3, good rubber hardness, volume resistivity, toner fusing property and bleeding property were obtained, but the frictional charge potential of the glass rod 12 showed a negative value. Further, in the elastic conductor made of the kneaded material P4 using the frictional charge control agent (polyamide) having the Hammett substituent constant of the electron-withdrawing group of "0", good rubber hardness, volume specific resistance value, and toner fusing property are obtained. However, the triboelectric charge potential of the glass rod 12 showed a negative value and bleeding was also observed.

On the other hand, a triboelectrification control agent (sodium di-2-ethylhexyl sulfosuccinate, sodium decylbenzene sulfonate, palmitic acid, perfluorooctyl sulfonate) having a Hammett substituent constant of the electron withdrawing group of "0.31" or more. , Para-toluene sulfonyl chloride, para-nitrotoluene), the elastic conductors made of the kneaded materials S1 to S6 have good rubber hardness, volume specific resistance value, toner fusion property, and bleeding property. The triboelectric charge potential shows a positive value, and it can be read that the sample 13 was charged to a positive potential. If the Hammett substituent constant σp of the electron-withdrawing group is “0.1” or more (for example, dodecylbenzene chloride (functional group; chlorine) having a Hammett substituent constant σp of the electron-withdrawing group of 0.23), Constant σ
It was confirmed that the same result as when p was "0.31" or more was obtained.

Therefore, in the elastic conductor of the regulating member,
By using a triboelectric charge control agent having a Hammett substituent constant of the electron-withdrawing group of "0.1" or more, bleed-out of the elastic conductor is prevented, and conductivity, flexibility, toner separation, and resistance It was confirmed that the abrasion resistance can be secured and the toner can be charged to a positive potential by charging the elastic conductor to a negative potential by frictional charging.

(Second Embodiment) In the second embodiment of the present invention, a urethane polymer (millable polyester urethane) is used as a polymer (base polymer), a fatty acid metal salt is used as a processing aid, and various additives having the formulations shown in Table 4 below. Conductive agent (acetylene black, conductive carbon black),
Using trimethylolpropane trimethacrylate as a cross-linking aid, an organic peroxide as a vulcanizing agent, and sodium di-2-ethylhexyl sulfosuccinate similar to the above kneaded material S1 as a frictional charge adjusting agent, and kneading the respective materials The kneaded products S11 to S15 are obtained by vulcanizing each of the kneaded products S11 to S15 into a rectangular flat plate shape (20 mm × 2).
(0 mm × 2 mm) elastic conductor was prepared, and triboelectrification potential, rubber hardness, toner fusing property, and bleeding property were examined by the same method as in the first embodiment, and the results are also shown in Table 4 below.

[0044]

[Table 4]

As shown in Table 4 above, the elastic conductors using the kneaded materials S11 and S12 in which the addition amount of the triboelectrification control agent was 0.2 parts by weight or less were excellent in rubber hardness, toner fusion property, and
Bleedability was obtained and the triboelectric charge potential of the glass rod 12 showed a positive value, but the magnitude of the triboelectric charge potential was not sufficient. Further, the elastic conductor using the kneaded material S15 containing 4 parts by weight of the triboelectric charge control agent has a good rubber hardness,
The toner fusion property was obtained, and the frictional charge potential of the glass rod 12 was a positive value, which was a sufficient value (200 V or more), but bleeding was observed.

On the other hand, the elastic conductor using the kneaded materials S13 and S14 in which the addition amount of the triboelectrification control agent is 0.5 to 2 parts by weight provides good rubber hardness, toner fusion property and bleeding property. The triboelectric potential of the glass rod 12 was a positive value, which was sufficiently large (200 V or more).

Therefore, in the elastic conductor of the regulating member,
It has been confirmed that it is preferable to add the triboelectrification regulator having a Hammett substituent constant of the electron-withdrawing group of "0.1" or more within the range of 0.5 to 2 parts by weight.

(Third Embodiment of the Present Invention) In the third embodiment of the present invention, a polar polymer (various millable polyester urethanes (1 to 3 in Tables 5 and 6)) having a composition shown in Table 5 below is used. Nitrile butadiene rubber, silicone rubber)
Or non-polar polymer (ethylene propylene rubber, styrene butadiene rubber), fatty acid metal salt as a processing aid, various conductive agents (acetylene black, conductive carbon black), trimethylolpropane trimethacrylate as a crosslinking aid, vulcanizing agent As various organic peroxides (Nos. 1 and 2 in Tables 5 and 6), and sodium di-2-ethylhexyl sulfosuccinate similar to the above kneaded material S1 are used as frictional charge control agents, and the respective materials are kneaded. Thus, kneaded materials S21 to S26 were produced. The trade names of the materials shown in Table 5 below are shown in Table 6 below.

[0049]

[Table 5]

[0050]

[Table 6]

Each of the kneaded products S21 to S2 shown in Table 5 above.
6 is vulcanized to form a rectangular flat plate (20 mm × 20 mm × 2 m
The elastic conductor (m) was prepared, and the triboelectric charge potential, rubber hardness, toner fusion property, and bleeding property were examined by the same method as in the second embodiment, and the results are shown in Table 7 below.

[0052]

[Table 7]

As shown in Table 7, the elastic conductor made of the kneaded materials S25 and S26 using the nonpolar polymer is
Good rubber hardness, toner fusion property, and bleeding property are obtained,
The triboelectric charge potential of the glass rod 12 showed a positive value, but the magnitude of the triboelectric charge potential was not sufficient (less than 200 V). On the other hand, a kneaded product S21-using a polar polymer
The elastic conductor made of S24 provided good rubber hardness, toner fusion property and bleeding property, and the frictional charging potential of the glass rod 12 was a positive value, which was sufficiently large (200 V or more).

Therefore, in the elastic conductor of the regulating member,
In order to charge the toner to a negative potential by triboelectrification and to positively charge the toner to a sufficient positive potential, a triboelectrification adjuster having a Hammett substituent constant of the electron-withdrawing group of “0.1” or more is used, It was confirmed that it is preferable to use the above polymer.

(Fourth Embodiment) In the fourth embodiment, the kneaded materials P1, P4, S11 to S13, S1,
S3 was used to produce the elastic conductors, respectively, and the elastic conductors were formed into the regulating members of the electrophotographic apparatus (the copying machine (GP405) manufactured by Canon Inc. in the fourth embodiment of the present embodiment) as shown in FIG. By measuring the charge amount and fog density of the toner layer regulated by the regulation member, the chargeability and fog property of each elastic conductor were examined.
The same components as those shown in FIG. 4 are designated by the same reference numerals, and detailed description thereof will be omitted.

First, the kneaded materials P1, P4, S11-
S13, S1, S3 are vulcanized to form a rectangular flat plate (1
5 mm × 230 mm × 1 mm) elastic conductors 8b are formed, and these elastic conductors are formed into a rectangular flat plate shape (25 mm × 230 mm).
(mm × 2 mm) holders 8a were joined to each other to produce the regulation members 3c, and the regulation members 3c were each configured as an electrophotographic apparatus as shown in FIG.

Then, the electrophotographic apparatus is driven so that the toner supplied onto the developing roller 3a is regulated by the regulating member 3 described above.
After being regulated by c, the regulated charge amount of the toner layer was measured by a Faraday gauge. Further, the fog density of the transfer paper on which the toner layer was copied was measured with a Macbeth densitometer. In addition, when the fog density was 1.6, it was determined as "black solid", and when the fog density was 0.1 or more, it was determined as defective printing.

The results of each of the above measurements are shown in Table 8 below. In Table 8, the symbol “◯” indicates that the fog density was low and the printing was good, and the symbol “x” indicates that the fog density was high and the printing was defective.

[0059]

[Table 8]

As shown in Table 8, the elastic conductors using the kneaded materials P1, P4, S11 and S12 having the frictional charging potential of the glass rod 12 of −500 V to 50 V measured in FIG. A sufficient amount of charge was not obtained and the fog density became high. On the other hand, the kneaded material S1 in which the triboelectric charge potential of the glass rod 12 is 200 V to 500 V
With the elastic conductors using 3, S1 and S3, a sufficient charge amount was obtained in the toner layer, and the fog density could be lowered.

Therefore, it was confirmed that in order to sufficiently suppress the fog density of the electrophotographic apparatus, it is necessary to use, as the elastic conductor of the regulating member, one that is charged to −200 V or less by frictional charging.

In the above, the present invention has been described in detail only with respect to the specific examples described, but it is apparent to those skilled in the art that various variations and modifications are possible within the scope of the technical idea of the present invention. It goes without saying that such variations and modifications belong to the scope of the claims.

[0063]

As described above, according to the present invention, it is possible to prevent bleed-out in the elastic conductor used as the regulating member and to secure good conductivity, flexibility, toner separation and abrasion resistance, and The elastic conductor can be charged to a sufficiently large negative potential, and the toner can be charged to a sufficiently large positive potential.

Therefore, in the electrophotographic apparatus, it is possible to cope with the recent increase in the output speed and to improve the copying efficiency (output printing efficiency).

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a method for measuring a triboelectric charge potential according to the present embodiment.

FIG. 2 is an explanatory diagram showing a method for measuring toner fusibility in the present embodiment.

FIG. 3 is an explanatory diagram showing a method for measuring bleeding property according to the present embodiment.

FIG. 4 is a schematic configuration diagram of a general electrophotographic apparatus.

[Explanation of symbols]

3 ... Developing device 3a ... Developing roller 3c ... Regulating member 8a ... Holder 8b, 13, 21a, 21b ... Elastic conductor 11 ... Surface electrometer 12 ... glass rod 22 ... Toner 23 ... weight 31 ... Plain paper

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] August 8, 2001 (2001.8.8)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0030

[Correction method] Change

[Correction content]

[0030]

[Table 2]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0050

[Correction method] Change

[Correction content]

[0050]

[Table 6]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08L 75/04 C08L 75/04 83/04 83/04 101/00 101/00 // B29K 9:00 B29K 9:00 75:00 75:00 83:00 83:00 105: 24 105: 24 F-term (reference) 2H077 AD13 AD23 AE03 4F201 AA31 AA33 AA46 AB03 AB13 AH33 AR20 BA01 BC02 BC37 4F203 AA45 AA46 AH04 DA11 DB01 DC01 4J002 AC071 CK021 CP031 DA036 EF057 EH047 EN027 EN117 ES017 EV217 EV237 FD116 FD127 FD140 GM00

Claims (4)

[Claims] 1. A polymer elastic body composition which regulates a one-component developer in a developing device on a developing roller and frictionally charges the one-component developer, comprising at least a polymer, a cross-linking agent, and a triboelectric charge control agent. Is kneaded and cross-linked, and the potential due to the above-mentioned triboelectric charging is -200
A polymer elastic body composition which is V or less. 2. The elastic polymer composition according to claim 1, wherein the triboelectric charge control agent has an electron-withdrawing group having a Hammett substituent constant σp of 0.1 or more. 3. The amount of the triboelectric charge control agent added is 0.5.
The elastic polymer composition according to claim 1 or 2, wherein the content is 2 to 2 parts by weight. 4. The elastic polymer composition according to claim 1, wherein the polymer is any one of urethane polymer, silicone polymer and nitrile butadiene rubber.