JP6629607B2 - Toner supply roll for electrophotographic equipment - Google Patents

Description

  The present invention relates to a toner supply roll for an electrophotographic device.

  A toner supply roll for an electrophotographic device used in an electrophotographic device such as a copying machine, a printer, and a printing machine usually has a shaft and a urethane foam layer formed on an outer periphery of the shaft and having a large number of cells. (See Patent Document 1).

Japanese Patent No. 5396250

  It is necessary that the toner supply roll for an electrophotographic apparatus has, as a basic performance, a toner supply property for stably supplying toner to a developing roll. If the toner supply property is poor, an image having a sufficient density cannot be obtained due to insufficient toner. In addition to the toner supply property, the toner supply roll for an electrophotographic apparatus also needs to have a toner scraping property for reliably scraping the residual toner on the surface of the developing roll. This is because if the toner scraping property is poor, image defects such as uneven density are likely to occur. Further, according to the findings of the present inventors, it has been found that when the toner is charged by friction with a toner supply roll for an electrophotographic apparatus, image defects due to uneven density can be reduced.

  However, with the cell structure of the urethane foam layer of the conventional toner supply roll for electrophotographic equipment, it is difficult to improve toner scraping properties and toner chargeability while ensuring toner supply properties.

  The present invention has been made in view of the above background, and an object of the present invention is to provide a toner supply roll for an electrophotographic apparatus capable of improving toner scraping property and toner charging property while ensuring toner supply property. Things.

One embodiment of the present invention is a toner supply roll for an electrophotographic device having a shaft and a urethane foam layer formed around the shaft and having a large number of cells,
The urethane foam layer,
Surface average cell diameter 180-280 μm,
Internal average cell diameter is 280-650 μm,
The surface area ratio of the cell skeleton is 30 to 60%,
It was seen for cells of the urethane foam layer surface, Ri average cell diameter difference der less 50μm axial end portions,
An ionic conductive agent composed of a salt of a cation and an anion having a reactive functional group that reacts with an isocyanate group is chemically bonded to the urethane foam layer through the reactive functional group,
The cation is represented by the following (formula 1), (formula 2), or (formula 3) :
In the toner supply roll for electrophotographic equipment.

The toner supply roll for the electrophotographic device, the surface average cell diameter of the urethane foam layer, the internal average cell diameter, the surface area ratio of the cell skeleton, and the cells on the surface of the urethane foam layer, both ends in the axial direction The average cell diameter difference is in a specific range. Therefore, the toner supply roll for an electrophotographic device can improve the toner scraping property and the toner charging property while securing the toner supply property.

FIG. 2 is an explanatory view schematically showing a toner supply roll for an electrophotographic device according to an embodiment. 4 is a laser microscope photograph of the surface of a urethane foam layer in a toner supply roll for an electrophotographic device of Sample 1. It is a laser microscope photograph of the urethane foam layer surface in the toner supply roll for electrophotographic apparatuses of the sample 2C.

  The toner supply roll for the electrophotographic device (hereinafter, may be simply referred to as “toner supply roll”) will be described.

  As the electrophotographic apparatus, specifically, an image forming apparatus such as an electrophotographic copying machine using a charged image, a printer, a facsimile, a multifunction machine, and an on-demand printing machine can be exemplified.

  Examples of the shaft body include a solid body (core metal) and a hollow body made of a metal (including an alloy) such as stainless steel, aluminum and iron, a solid body and a hollow body made of a conductive plastic, a conductive or non-conductive plastic. And a solid body made of and a metal body plated with metal.

  In the urethane foam layer, the average surface cell diameter is in the range of 180 to 280 μm. If the average surface cell diameter is less than 180 μm, the number of cells that are small relative to the toner increases, and the toner supply property decreases. As a result, an image having a sufficient density cannot be obtained. The surface average cell diameter is preferably 185 μm or more, more preferably 190 μm or more, and still more preferably 200 μm or more, from the viewpoint of improving toner supply properties. On the other hand, when the surface average cell diameter exceeds 280 μm, the number of cells larger than the toner increases, the frequency of contact with the toner on the cell skeleton decreases, and the toner scraping property decreases. As a result, image defects such as density unevenness tend to occur. The surface average cell diameter can be preferably 270 μm or less, more preferably 260 μm or less, and still more preferably 250 μm or less, from the viewpoint of improving the toner scraping property.

  The surface average cell diameter is a value measured as follows. That is, using a laser microscope (manufactured by Keyence Corporation, “Shape measuring laser microscope VK-8700” or an equivalent product when this is not available), the center of the urethane foam layer in the axial direction, and the above-mentioned central side from one end face in the axial direction. 12 points at 20 mm from the other end face in the axial direction, and 4 points at equal intervals in the circumferential direction at three points at a position 20 mm from the other end face in the axial direction to the center side, for a total of 3 points × 4 points = 12 measurement points Observe the urethane foam layer surface. The observation area is an area of about 1 mm × 1.4 mm. Twenty cells are selected per observation region, and the diameter of the largest inscribed circle inscribed in the cell skeleton of each cell is measured. The average value of the diameters of the inscribed circles measured for the twelve observation areas is defined as the surface average cell diameter.

  In the urethane foam layer, the average internal cell diameter is in the range of 280 to 650 μm. When the internal average cell diameter is less than 280 μm, the toner tends to clog the cells inside the urethane foam layer, and the toner supply property is reduced. As a result, an image having a sufficient density cannot be obtained. The internal average cell diameter is preferably 290 μm or more, more preferably 300 μm or more, and further preferably 320 μm or more, from the viewpoint of improving toner supply properties. On the other hand, when the internal average cell diameter exceeds 650 μm, the toner holding property during rotation of the toner supply roll is reduced, and the toner is easily spilled from the urethane foam layer, so that the toner supply property is reduced. As a result, an image having a sufficient density cannot be obtained. The internal average cell diameter is preferably 600 μm or less, more preferably 550 μm or less, and still more preferably 500 μm or less, from the viewpoint of improving toner supply properties.

  The internal average cell diameter is a value measured as follows. That is, using a scanning electron microscope (SEM), the urethane foam layer is formed at a depth of 2 mm from four surface positions at equal intervals in the circumferential direction in a cross section when the urethane foam layer is cut at the center in the axial direction. Observe the cross section. The observation area is an area of about 1 mm × 1.4 mm. Ten cells are selected per observation region, and the diameter of the largest inscribed circle inscribed in the cell skeleton of each cell is measured. The average value of the diameters of the inscribed circles measured for the four observation areas is defined as the internal average cell diameter.

  In the urethane foam layer, the surface area ratio of the cell skeleton is in the range of 30 to 60%. When the surface area ratio of the cell skeleton is less than 30%, the contact area of the cell skeleton with the toner on the surface of the urethane foam layer is reduced, and the chargeability of the toner due to triboelectric charging is reduced. Further, the toner scraping property is also reduced. As a result, image defects such as density unevenness tend to occur. The surface area ratio of the cell skeleton portion is preferably 31% or more, more preferably 33% or more, and still more preferably 35% or more, from the viewpoint of improving the toner chargeability and the toner scraping property. . On the other hand, if the surface area ratio of the cell skeleton exceeds 60%, the ratio of cells appearing on the surface of the urethane foam layer decreases, and the toner supply property decreases. As a result, an image having a sufficient density cannot be obtained. The surface area ratio of the cell skeleton portion is preferably 58% or less, more preferably 50% or less, and further preferably 45% or less, from the viewpoint of improving toner supply properties.

  The surface area ratio of the cell skeleton is a value measured as follows. That is, using a laser microscope (manufactured by Keyence Corporation, “Shape measuring laser microscope VK-8700” or an equivalent product when this is not available), the center of the urethane foam layer in the axial direction, and the above-mentioned central side from one end face in the axial direction. 12 points at 20 mm from the other end face in the axial direction, and 4 points at equal intervals in the circumferential direction at three points at a position 20 mm from the other end face in the axial direction to the center side, for a total of 3 points × 4 points = 12 measurement points Observe the urethane foam layer surface. The observation area is an area of about 0.5 mm × 0.7 mm. Then, the area ratio of the cell skeleton portion in each observation region is measured using image analysis software of a laser microscope. The average value of the area ratios of the cell skeletons measured for the 12 observation regions is defined as the surface area ratio of the cell skeleton.

  In the urethane foam layer, the average cell diameter difference between both ends in the axial direction is 50 μm or less. If the average cell diameter difference exceeds 50 μm, the toner supply property varies in the axial direction of the urethane foam layer. As a result, image defects such as density unevenness tend to occur. The average cell diameter difference between both ends in the axial direction can be preferably 48 μm or less, more preferably 40 μm or less, and still more preferably 30 μm or less, from the viewpoint of reducing the variation in the toner supply properties in the axial direction.

  The average cell diameter difference between both ends in the axial direction is a value measured as follows. That is, a laser microscope (manufactured by KEYENCE CORPORATION, “Shape measuring laser microscope VK-8700”, or an equivalent product when this is not available) is inserted into the urethane foam layer by 20 mm in the axial center from one end face in the axial direction. The surface of the urethane foam layer is observed at four measurement points at equal intervals in the circumferential direction at the set positions. The observation area is an area of about 1 mm × 1.4 mm. Twenty cells are selected per observation region, and the diameter of the largest inscribed circle inscribed in the cell skeleton of each cell is measured. The average value of the diameters of the inscribed circles measured for the four observation regions is defined as the average cell diameter R at one end in the axial direction. Similarly, the average cell diameter L on the other end side in the axial direction is obtained. The absolute value of the difference between the average cell diameter R at one end in the axial direction and the average cell diameter L at the other end in the axial direction is defined as the average cell diameter difference at both ends in the axial direction.

The toner supply roll is configured such that an ion conductive agent composed of a salt of a cation and an anion having a reactive functional group that reacts with an isocyanate group is chemically bonded to the urethane foam layer via the reactive functional group. that it has been the.

The above configuration can be obtained, for example, by foaming and curing a urethane composition containing the ionic conductive agent. During this foaming hardening, the surface activity of the ionic conductive agent and the like, the surface average cell diameter of the urethane foam layer, the internal average cell diameter, the surface area ratio of the cell skeleton, and the cells on the surface of the urethane foam layer were observed. The average cell diameter difference at both ends in the axial direction tends to be in the above-described specific range. Therefore, according to the above configuration, it is easy to obtain a toner supply roll capable of improving the toner scraping property and the toner charging property while securing the toner supply property. When the urethane composition contains a foam stabilizer such as a silicone-based foam stabilizer, the interaction with the ionic conductive agent causes the urethane foam layer to have a surface average cell diameter, an internal average cell diameter, and a surface of the cell skeleton. The area ratio and the average cell diameter difference between both ends in the axial direction are more likely to be in the specific ranges described above. Note that the foam stabilizer is included in the urethane foam layer. Further, in the above configuration, since the cation side of the ionic conductive agent is chemically bonded to the urethane foam layer via the reactive functional group, the ionic conductive agent does not easily exude from the urethane foam layer, and the exuded ionic conductive agent is It becomes easy to suppress cling to the toner. Therefore, according to the above configuration, the chargeability of the toner can be easily improved. Furthermore, conductivity is given to the urethane foam layer by the ionic conductive agent chemically bonded to the urethane foam layer, and it is easy to reduce the electric resistance of the urethane foam layer. Therefore, according to the above configuration, not only is the toner physically supplied to the developing roll and the toner remaining on the developing roll is physically scraped, but also a voltage is applied to the urethane foam layer, In addition, there is an advantage that the toner can be supplied and the toner can be scraped off.

  As the reactive functional group of the cation in the ionic conductive agent, for example, at least one of a hydroxyl group and an amino group can be used. In this case, since the reaction of the isocyanate in the urethane composition used for forming the urethane foam layer with the isocyanate group can be ensured, the above-described effects can be ensured.

  As the anion in the ionic conductive agent, for example, at least one of a bis (fluorosulfonyl) imide (FSI) anion and a bis (trifluoromethanesulfonyl) imide (TFSI) anion can be used. This is advantageous for improving the chargeability of the toner and reducing the electric resistance of the urethane foam layer.

  As the ionic conductive agent, more specifically, a salt of a cation having a hydroxyl group and an FSI anion, a salt of a cation having a hydroxyl group and a TFSI anion, a salt of a cation having an amino group and a FSI anion A salt of a cation having an amino group and a TFSI anion, a salt of a cation having a hydroxyl group and an amino group and an FSI anion, and a salt of a cation having a hydroxyl group and an amino group and a TFSI anion. . In the toner supply roll, one or more ion conductive agents may be chemically bonded to the urethane foam layer.

Examples of the cation with at least one hydroxyl group and an amino group as a reactive functional group, more specifically, the following (Equation 1), is used as shown in (Equation 2). In addition, as the cation, those shown in (Equation 3) shown in an experimental example described later are also used.

  In the toner supply roll, the content of the ionic conductive agent contained in the urethane composition used for forming the urethane foam layer is in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the polyol contained in the urethane composition. It can be.

  In this case, it is easy to obtain a toner supply roll capable of improving the toner scraping property and the toner charging property while securing the toner supply property.

  The content of the ionic conductive agent is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and still more preferably 1 part by mass or more, from the viewpoint of ensuring the above-mentioned effects. can do. In addition, the content of the ionic conductive agent is preferably 8 parts by mass or less, more preferably 5 parts by mass or less, and still more preferably 3 parts by mass or less from the viewpoint of ensuring the above-mentioned effects. Can be.

  The toner supply roll preferably has an extraction amount of the extract from the urethane foam layer with acetone of 4% by mass or less. In this case, it is easy to suppress the extracted components oozing out of the urethane foam layer from clinging to the toner. Therefore, in this case, the chargeability of the toner is easily improved.

  The amount of extraction can be preferably 3.8% by mass or less, more preferably 3.5% by mass or less, and even more preferably 3% by mass or less, from the viewpoint of improving toner chargeability and the like. In addition, the said extraction amount is measured as follows. The urethane foam layer is peeled off from the toner supply roll. The peeled urethane foam layer is immersed in acetone for 1 hour, and the dry weight before and after immersion is measured. Then, the extraction amount (%) is calculated from the formula of 100 × {(dry mass of urethane foam layer before immersion) − (dry mass of urethane foam layer after immersion)} / (dry mass of urethane foam layer before immersion). calculate.

In the toner supply roll, the urethane foam layer may be formed of, for example, a foamed cured product of a urethane composition containing the following components (A) to (F).
(A) polyol, (B) isocyanate, (C) the above ionic conductive agent, (D) foam stabilizer, (E) water (blowing agent), (F) amine catalyst

  The urethane composition may further include a crosslinking agent and the like. Examples of the foam stabilizer (D) include silicone foam stabilizers. For the components other than the component (C), for example, a known urethane foam layer material described in Japanese Patent No. 5396250 can be used.

  Note that the above-described configurations can be arbitrarily combined as necessary to obtain the above-described functions and effects.

  Hereinafter, a toner supply roll for an electrophotographic apparatus according to an embodiment will be described with reference to the drawings.

(Example 1)
First Embodiment A toner supply roll for an electrophotographic apparatus according to a first embodiment will be described with reference to FIG. As shown in FIG. 1, a toner supply roll 1 for an electrophotographic device according to the present embodiment has a shaft 2 and a urethane foam layer 3. The urethane foam layer 3 is formed on the outer periphery of the shaft body 2 and has many cells (not shown).

The urethane foam layer 3 has a surface average cell diameter of 180 to 280 μm, an internal average cell diameter of 280 to 650 μm, a surface area ratio of the cell skeleton portion of 30 to 60%, and an axial direction as viewed from the cells on the surface of the urethane foam layer 3. The average cell diameter difference between both ends is set to 50 μm or less.

In this example, an ionic conductive agent composed of a salt of a cation and an anion having a reactive functional group that reacts with an isocyanate group is chemically bonded to the urethane foam layer 3 via the reactive functional group. The ionic conductive agent is specifically a salt of a cation having at least one of a hydroxyl group and an amino group as a reactive functional group, and an FSI anion or a TFSI anion. The cation is specifically represented by the above-described (Equation 1), (Equation 2), or (Equation 3) described later in an experimental example.

  Hereinafter, a plurality of toner supply roll samples for electrophotographic equipment were prepared and evaluated. An experimental example will be described.

(Experimental example)
The following materials were prepared as materials of the urethane composition used for forming the urethane foam layer.

-Polyol-
-Polyether polyol (polypropylene glycol) (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., "Hiflex G3000")
-Isocyanate-
・ Toluene diisocyanate (TDI) (Mitsui Chemical Polyurethanes, Cosmonate T80)
-4,4'-diphenylmethane diisocyanate (MDI) ("Sumidur 44V20", manufactured by Sumitomo Bayer Urethane Co., Ltd.)

-Ionic conductive agent-
-Ion conductive agent A (salt of cation represented by the above formula (1) and bis (trifluoromethanesulfonyl) imide (TFSI) anion)
-Ion conductive agent B (salt of cation represented by the following formula (3) and bis (fluorosulfonyl) imide (FSI) anion)
-Ion conductive agent C (salt of the cation represented by the above formula (2) and bis (trifluoromethanesulfonyl) imide (TFSI) anion)

-Foam stabilizer-
・ Silicone foam stabilizer A (manufactured by Toray Dow Corning, "SZ-1360")
-Silicone foam stabilizer B (SZ-1327, manufactured by Dow Corning Toray)
-Blowing agent-
・ Water-amine catalyst-
・ Dimethylaminoethylmorpholine ・ Triethylenediamine (TEDA)
-Crosslinking agent-
・ Diethanolamine

<Preparation of toner supply roll sample>
A mold having a cylindrical mold having a length substantially equal to the axial length of the urethane foam layer in the toner supply roll and caps for closing both ends of the cylindrical mold was prepared. A core metal (diameter: 5 mm, made of SUS304) serving as a shaft was set on the central axis in the cylindrical mold in the molding die, and both ends of the cylindrical mold were closed with caps. Note that the cylindrical type is arranged so that the central axis is along the vertical direction. Next, a urethane composition obtained by mixing a premix obtained by mixing the materials shown in Table 1 (excluding isocyanate) at the ratio shown in the table and isocyanate at the ratio shown in the table is injected from one side of the cylindrical molding cavity. did. This was heated in a 60 ° C. oven for 30 minutes to foam and harden, and then removed from the mold. In this way, toner supply rolls of Samples 1 to 7 and 1C to 4C having a urethane foam layer (length in the axial direction, 225 mm in length and 4.1 mm in thickness) on the outer peripheral surface of the shaft were produced.

<Surface average cell diameter of urethane foam layer, internal average cell diameter, surface area ratio of cell skeleton, and average cell diameter difference between both ends in axial direction>
According to the above-described measurement method, the surface average cell diameter, the internal average cell diameter, the surface area ratio of the cell skeleton portion, and the average cell diameter difference at both ends in the axial direction were obtained for the urethane foam layer in each toner supply roll.

<Extracted amount of extract from urethane foam layer>
According to the measurement method described above, the amount of the extract from the urethane foam layer with acetone was measured for each toner supply roll.

<Image density>
Each toner supply roll was incorporated in a developing device of a commercially available printer (“Color LaserJet CP1215”, manufactured by Hewlett-Packard), and a solid image was printed. "A" when the density of the printed image was sufficient, "B" when the printed image was slightly blurred but was within a practically acceptable range, and "Density" of the printed image Was insufficient and practical use was difficult, and was rated "C".

<Image density unevenness>
Each toner supply roll was incorporated in a developing device of a commercially available printer (“Color LaserJet CP1215”, manufactured by Hewlett-Packard), and a solid image was printed. “A” indicates that the printed image has no density unevenness, and “B” indicates that the printed image has some density unevenness but is within a practically acceptable range, and indicates the density of the printed image. The case where there was unevenness and it was difficult to put to practical use was designated "C".

  Table 1 summarizes the detailed configuration and evaluation results of the toner supply roll sample.

  Table 1 shows the following. That is, the toner supply roll of Sample 1C has a surface average cell diameter of less than 180 μm in the urethane foam layer. Therefore, the toner supply roll of the sample 1C could not obtain an image having a sufficient density. This is because the number of small cells increases with respect to the toner, and the toner supply property decreases. In the toner supply roll of Sample 1C, the surface area ratio of the cell skeleton is less than 30%. As a result, the toner supply roll of Sample 1C had an image defect such as uneven density. This is because the contact area of the cell skeleton portion in contact with the toner on the surface of the urethane foam layer is reduced, and the chargeability of the toner due to frictional charging is reduced, and the scraping property of the toner is reduced.

  The toner supply roll of the sample 2C has a surface average cell diameter exceeding 280 μm. Therefore, the toner supply roll of the sample 2C had an image defect of uneven density. This is because the number of large cells increases with respect to the toner, the frequency at which the toner hits the cell skeleton decreases, and the toner scraping property decreases. In the toner supply roll of Sample 2C, the surface area ratio of the cell skeleton exceeds 60%. Therefore, an image having a sufficient density was not obtained with the toner supply roll of Sample 2C. This is because the ratio of cells appearing on the surface of the urethane foam layer was reduced, and the toner supply property was reduced.

  The toner supply roll of Sample 3C has an internal average cell diameter of less than 280 μm. Therefore, an image having a sufficient density was not obtained with the toner supply roll of Sample 3C. This is because the toner easily clogs the cells inside the urethane foam layer, and the toner supply property is reduced.

  The toner supply roll of Sample 4C has an internal average cell diameter exceeding 650 μm. Therefore, the toner supply roll of the sample 4C could not obtain an image having a sufficient density. This is because the toner supply roll of the sample 4C has a reduced toner holding property when the toner supply roll rotates, and the toner tends to spill from the urethane foam layer, resulting in a decrease in the toner supply property. In the toner supply roll of Sample 4C, the average cell diameter difference between both ends in the axial direction of the urethane foam layer exceeds 50 μm. For this reason, the toner supply roll of the sample 4C had an image defect of uneven density. This is because the toner supply property varied in the axial direction of the urethane foam layer.

  On the other hand, the toner supply rolls of Samples 1 to 7 provided images having a sufficient density and did not cause image defects such as uneven density. This is because, in the toner supply rolls of Sample 1 to Sample 7, the surface average cell diameter of the urethane foam layer, the internal average cell diameter, the surface area ratio of the cell skeleton, and the average cell diameter difference at both ends in the axial direction are specific. The reason for this is that the toner scraping property and the toner charging property can be improved while ensuring the toner supply property.

  In addition, the toner supply rolls of Samples 1 to 7 were formed by foaming and curing a urethane composition containing an ionic conductive agent, even though the urethane foam layer was formed. The amount of extraction is relatively small. This is because the cationic side of the ionic conductive agent was chemically bonded to the urethane foam layer via the reactive functional group, so that the ionic conductive agent did not easily seep out of the urethane foam layer. However, when the content of the ionic conductive agent contained in the urethane composition increases, as in the toner supply roll of Sample 6, the amount of the extract extracted from the urethane foam layer increases, and the toner chargeability decreases and the concentration decreases. There was a tendency for unevenness to occur. This is considered to be due to an increase in unreacted ionic conductive agents that did not chemically bond to the urethane foam layer, depending on the amount of isocyanate used. Therefore, it can be said that the content of the ionic conductive agent contained in the urethane composition is preferably limited to 10 parts by mass or less based on 100 parts by mass of the polyol.

  As described above, the embodiments of the present invention have been described in detail. However, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 Toner supply roll for electrophotographic equipment 2 Shaft 3 Urethane foam layer

Claims (4)

A toner supply roll for an electrophotographic device having a shaft and a urethane foam layer formed on the outer periphery of the shaft and having a large number of cells,
The urethane foam layer,
Surface average cell diameter 180-280 μm,
Internal average cell diameter is 280-650 μm,
The surface area ratio of the cell skeleton is 30 to 60%,
It was seen for cells of the urethane foam layer surface, Ri average cell diameter difference der less 50μm axial end portions,
An ionic conductive agent composed of a salt of a cation and an anion having a reactive functional group that reacts with an isocyanate group is chemically bonded to the urethane foam layer via the reactive functional group,
The cation is represented by the following (formula 1), (formula 2), or (formula 3) :
Toner supply roll for electrophotographic equipment.
It said anion is bis (fluorosulfonyl) imide anion, and bis is at least one of (trifluoromethanesulfonyl) imide anion, a toner supply roll for electrophotographic apparatus according to claim 1. The content of the ion conductive agent contained in the urethane composition used for forming the urethane foam layer is 0.01 to 10 parts by mass with respect to the polyol 100 parts by weight contained in the urethane composition, according to claim 1 Or the toner supply roll for an electrophotographic apparatus according to 2 . Extraction of the extract from the urethane foam layer with acetone is 4 mass% or less, the electrophotographic apparatus for the toner supply roll according to any one of claims 1-3.