WO2019208296A1

WO2019208296A1 - Paper feed roll

Info

Publication number: WO2019208296A1
Application number: PCT/JP2019/016118
Authority: WO
Inventors: 和志山口
Original assignee: 住友理工株式会社
Priority date: 2018-04-27
Filing date: 2019-04-15
Publication date: 2019-10-31
Also published as: CN111867949B; JP6956678B2; JP2019189420A; US20200399084A1; CN111867949A

Abstract

Provided is a paper feed roll such that conveyance failures of paper are suppressed over a long period of time. This paper feed roll 10 comprises a shaft body 12 and an elastic body layer 14 formed on the outer periphery of the shaft body 12. A plurality of protrusions 16 that form surface unevenness are formed on the peripheral surface of the elastic layer 14. When a glass plate is pressed against the peripheral surface of the paper feed roll 10 with a load of 0.5 to 2.3 N per cm length in the axial direction, the entire area of the portion in contact with the glass surface is 1.0 to 15% of the nip area with the glass surface.

Description

Paper feed roll

The present invention relates to a paper feed roll suitably used in an electrophotographic apparatus such as a copying machine, a printer, and a facsimile employing an electrophotographic system.

The paper feed roll is formed in a cylindrical shape by an elastic material such as a rubber cross-linked body, and its peripheral surface serves as a contact surface with the paper. Paper dust generated from the paper may adhere to the peripheral surface of the paper feed roll. Then, paper powder may accumulate on the peripheral surface of the paper feed roll while repeatedly contacting the paper. When paper dust accumulates, the contact area of the peripheral surface with respect to the paper decreases, and the friction coefficient of the contact surface with respect to the paper decreases. As a result, a paper conveyance failure may occur.

In order to suppress paper conveyance failure, a paper feed roll having an uneven surface is known (Patent Document 1). For example, Patent Document 1 describes a configuration in which a plurality of ridges and grooves are formed in parallel with the axial direction of the paper feed roll.

JP 2017-65907 A

The conventional paper feed roll is still not sufficient in terms of maintaining a good coefficient of friction from the initial use for a long period of time. In particular, among the papers used in recent years, there are low-quality papers, and low-quality papers are likely to generate paper dust, and are likely to cause paper conveyance failure relatively early.

The problem to be solved by the present invention is to provide a paper feed roll that suppresses paper conveyance failure over a long period of time.

In order to solve the above problems, a paper feed roll according to the present invention is a paper feed roll of an electrophotographic apparatus having a shaft body and an elastic body layer formed on the outer periphery of the shaft body, wherein the elastic body layer Are provided with a plurality of convex portions for forming surface irregularities, and a glass plate is pushed to the peripheral surface of the paper feed roll with a load of 0.5 to 2.3 N per 1 cm in the axial length. The gist of the invention is that the contact area of the entire portion that is in contact with the glass surface when applied is 1.0 to 15% of the nip area with the glass surface.

In the paper feed roll according to the present invention, it is preferable that the ratio of the contact area per convex portion of the entire portion in contact with the glass surface is 0.02 to 10%. Moreover, it is preferable that the plurality of convex portions are regularly arranged on the peripheral surface of the elastic body layer. The plurality of convex portions may be composed of two types of convex portions having different heights. In this case, it is preferable that the height of the low convex portion of the two types of convex portions having different heights is 70 to 80% of the height of the high convex portion.

The paper feed roll according to the present invention is in contact with the glass surface when the glass plate is pressed against the peripheral surface of the paper feed roll with a load of 0.5 to 2.3 N per 1 cm in the axial length. The contact area of the entire part is 1.0 to 15% of the nip area with the glass surface, and by reducing the contact area to the glass surface, the contact area to the paper during transport of the paper is reduced. The amount of paper dust generated due to shaving is reduced. In addition, because the paper contact area is small, the paper dust generated during the conveyance of the paper immediately moves from the convex part of the roll surface to the concave part, and the paper powder stays in and adheres to the paper contact part. Reduction in friction coefficient is suppressed. Thereby, the conveyance failure of a sheet | seat is suppressed over a long term.

If the ratio of the contact area per convex portion of the entire portion in contact with the glass surface is 0.02 to 10%, the contact with the paper during conveyance of the paper per convex portion Since the area is also small, the amount of paper dust generated due to paper scraping and the reduction of the friction coefficient can be further suppressed. If a plurality of convex portions are regularly arranged on the peripheral surface of the elastic layer, a concave groove continuous in the arrangement direction is formed, and this groove is a discharge path for paper dust generated during paper conveyance. Thus, it becomes easy to discharge the paper dust outside the roll, and therefore, a reduction in the friction coefficient due to the accumulation of the paper dust can be suppressed. And if a plurality of convex parts consist of two kinds of convex parts having different heights, the high convex part mainly supports the load (load) of the entire roll, so the load (load) to the low convex part can be reduced, and the roll It is easy to reduce the total contact area with the paper. Further, since the low convex portion contributes to the conveyance of the sheet even if the contact load is small, the conveyance force of the sheet is secured and the conveyance failure of the sheet is easily suppressed.

It is an external appearance schematic diagram of the paper feed roll which concerns on one Embodiment of this invention. It is an example of the shape of the some convex part provided in the surrounding surface of the elastic body layer of a paper feed roll. It is an example of the arrangement | sequence of the some convex part provided in the surrounding surface of the elastic body layer of a paper feed roll. It is the figure which showed the method of calculating | requiring the area ratio of an actual contact part when a glass plate is pressed on the surrounding surface of a paper feed roll. 3 is an observation photograph of a nip portion when a glass plate is pressed against the peripheral surface of the paper feed roll of Example 1. FIG.

The paper feed roll according to the present invention (hereinafter sometimes simply referred to as a paper feed roll) will be described in detail. FIG. 1 is a schematic external view of a paper feed roll according to an embodiment of the present invention.

The paper feed roll 10 according to an embodiment of the present invention includes a shaft body 12 and an elastic body layer 14 formed on the outer periphery of the shaft body 12. The elastic layer 14 is a layer (outermost layer) that appears on the surface of the paper feed roll 10. The elastic body layer 14 has a tube shape (cylindrical shape). On the peripheral surface of the elastic body layer 14, a plurality of convex portions 16 that form surface irregularities are provided. Between the convex part 16 and the convex part 16, it is a recessed part lower than the convex part 16, and the unevenness | corrugation is provided in the surrounding surface of the elastic body layer 14 by the some convex part 16. FIG.

The paper feed roll 10 has an axial length of 0 per 1 cm in the axial direction on the peripheral surface of the paper feed roll 10 (here, the peripheral surface of the elastic layer 14) so that the contact area with the paper becomes small when the paper is conveyed. The contact area of the entire portion in contact with the glass surface when the glass plate is pressed with a load of 0.5 to 2.3 N (total area of the actual contact portion) is 1.0 to 1.0% of the nip area with the glass surface. 15%. The nip area is the area of the entire nip portion as a region that is recessed when the glass plate is pressed against the peripheral surface of the paper feed roll 10, and the contact area is actually in contact with the glass surface of the entire nip portion. The area of the entire part. By reducing the contact area to the glass surface, the contact area to the paper during conveyance of the paper is reduced, so that the amount of paper dust generated due to scraping of the paper can be suppressed. In addition, because the paper contact area is small, the paper dust generated during the conveyance of the paper immediately moves from the convex part of the roll surface to the concave part, and the paper powder stays in and adheres to the paper contact part. Reduction in friction coefficient is suppressed. Thereby, the conveyance failure of a sheet | seat is suppressed over a long term. The contact area is more preferably in the range of 3.0 to 12% of the nip area, and still more preferably in the range of 5.0 to 12% of the nip area.

The ratio of the contact area (total area of the actual contact portion) is obtained by observing a predetermined range in the nip portion with a microscope when the glass plate is pressed against the peripheral surface of the paper feed roll 10 with a predetermined load. Can do. The ratio of the contact area (the total area of the actual contact portions) can be adjusted by the shape of the protrusions, the density of the protrusions, the elasticity (material) of the protrusions, and the like.

In the paper feed roll 10, it is preferable that the ratio of the contact area per convex portion of the entire portion in contact with the glass surface is smaller. Since the contact area per sheet during conveyance of the sheet per convex portion is reduced, the amount of generated paper dust and the friction coefficient due to scraping of the sheet can be further suppressed. From this viewpoint, the ratio of the contact area per protrusion is preferably 0.02 to 10%. More preferably, it is 0.1 to 5%. The ratio of the contact area per protrusion (the area of the actual contact portion) is determined by observing a predetermined range in the nip portion with a microscope when the glass plate is pressed against the peripheral surface of the paper feed roll 10 with a predetermined load. Can be obtained.

The plurality of convex portions 16 may be composed of convex portions having the same height, or may be composed of convex portions having different heights. When the plurality of convex portions 16 are composed of two types of convex portions having different heights, the high convex portion mainly supports the load (load) of the entire roll, so the load (load) to the low convex portion can be reduced, and the entire roll It is easy to reduce the contact area with the paper. Further, since the low convex portion contributes to the conveyance of the sheet even if the contact load is small, the conveyance force of the sheet is secured and the conveyance failure of the sheet is easily suppressed. In this case, the height of the low convex portion of the two types of convex portions having different heights may be 70 to 80% of the height of the high convex portion.

The height of the convex portion 16 is not particularly limited, but is preferably in the range of 0.02 to 0.40 mm. When the height of the convex portion 16 is 0.02 mm or more, the volume of the concave portion between the convex portion 16 and the convex portion 16 is increased, and the generated paper powder is less likely to clog the concave portion. From this viewpoint, the height of the convex portion 16 is more preferably 0.05 mm or more. In addition, when the height of the convex portion 16 is 0.40 mm or less, the diameter of the lower base of the convex portion 16 can be suppressed to be appropriately small. improves. Thereby, generation | occurrence | production of paper dust becomes easy to be suppressed. From this viewpoint, the height of the convex portion 16 is more preferably 0.30 mm or less.

In FIG. 1, the convex part 16 is a hemispherical convex part. The spherical shape is substantially spherical and may be any shape close to a spherical shape having a curved surface. The spherical shape includes a true spherical shape and an elliptical spherical shape. A hemisphere is a half of a sphere cut by a plane that passes through the center of the sphere, a half of a sphere that is cut by a plane that does not pass through the center of the sphere, or a half of the sphere Are also included.

In FIG. 1, the plurality of convex portions 16 are uniformly distributed and arranged on the peripheral surface of the elastic body layer 14. The plurality of convex portions 16 may be randomly arranged on the peripheral surface of the elastic layer 14 or may be arranged so as to be arranged.

In FIG. 1, the plurality of convex portions 16 are arranged on the circumferential surface of the elastic body layer 14 so as to be arranged in the axial direction and the circumferential direction. Between the rows of the convex portions 16 arranged in the circumferential direction, there are continuous concave grooves. In addition, a continuous concave groove is formed between the rows of the convex portions 16 arranged in the axial direction. Since the groove of the concave part continuous in the circumferential direction is formed in the rotation direction of the paper feed roll 10, the paper powder moved from the convex part 16 to the groove of the concave part does not stay in the groove as the roll rotates. It is easy to be discharged out of the roll from the groove. In other words, the grooves serve as a discharge path for paper dust generated when the paper is transported, and the paper powder is easily discharged out of the roll. Therefore, it is easy to suppress a decrease in the coefficient of friction due to the accumulation of paper powder.

The shape of the plurality of convex portions provided on the peripheral surface of the elastic body layer 14 is not limited to the hemispherical convex portion 16 shown in FIG. 1 and may be various shapes. Examples of the shape of the convex portion include an indeterminate shape, a columnar body, a cone, a base, and a wedge shape. Examples of the columnar body include a cylindrical body, an elliptical columnar body, a rectangular columnar body (such as a quadrangular columnar body and a pentagonal columnar body), a fan-shaped columnar body, a D-shaped columnar body, and a gear-shaped columnar body. Further, it may be a truncated columnar body (a truncated columnar body, a truncated prismatic body, etc.) having a shape in which the head of the column body is cut into a slope shape or a curved surface shape. Examples of the cone include a cone, an elliptical cone, and a pyramid (such as a quadrangular pyramid and a pentagonal pyramid). Further, a truncated cone (such as a truncated cone and a truncated pyramid) having a shape in which the head of the cone is cut into a flat shape (frustum), a slope shape, or a curved surface may be used. The base is a solid that is shaped like a sphere cut out in two parallel planes. When the spherical surface intersects two parallel planes, the portion of the spherical surface sandwiched between these two planes is a spherical zone, and a solid surrounded by the spherical zone and these two planes is a base. One of the two planes of the base may be a plane that passes through the center of the sphere, or both of the two planes of the base may be a plane that does not pass through the center of the sphere. The two planes of the pedestal may be planes close to the plane, and may be curved surfaces having a larger radius of curvature than the ball belt, for example. Moreover, each upper bottom (upper plane) of a cylinder, an elliptical cylinder, a prism, a fan-shaped cylinder, a D-shaped cylinder, a gear-shaped cylinder, a frustum, and a ball base may be a polished surface. The polished surface can be formed by polishing each upper bottom.

FIG. 2 shows an example of the shape of a plurality of convex portions provided on the peripheral surface of the elastic layer 14. FIG. 2A shows a convex portion 161 having a shape (conical frustum shape) in which the head portion of the cone is cut out by a plane parallel to the bottom surface. FIG. 2B is the hemispherical convex portion 16 shown in FIG. FIG. 2C shows a columnar convex portion 162. FIG. 2D shows a quadrangular prism-shaped convex portion 163. FIG. 2E shows a convex portion 164 having a shape (square pyramid trapezoidal shape) in which the head of the quadrangular pyramid is cut out by a plane parallel to the bottom surface.

The plurality of convex portions provided on the peripheral surface of the elastic layer 14 may be composed of only one of these various convex portions, or may be composed of a combination of two or more. For example, a hemispherical convex portion 16 and a truncated cone-shaped convex portion 161 may be included on the peripheral surface of the elastic body layer 14 of one paper feed roll 10.

The plurality of convex portions provided on the peripheral surface of the elastic layer 14 may be arranged in an arrangement form other than the arrangement form shown in FIG. FIG. 3 shows another arrangement form of the plurality of convex portions.

3A, a plurality of convex portions 16 are arranged in a staggered pattern on the peripheral surface of the elastic layer 14. Specifically, the second row of convex portions 16 is disposed between the first row of convex portions 16 and the convex portions 16, and the third row of convex portions 16 is disposed between the second row of convex portions 16 and the convex portions 16. Are arranged, and the convex portions 16 in the fourth row are arranged between the convex portions 16 in the third row, and the convex portions 16 are arranged alternately. In the paper feed roll 20 in FIG. 3A, the plurality of convex portions 16 are particularly uniformly arranged on the peripheral surface of the elastic body layer 14. For this reason, the contact with the paper during the conveyance of the paper is particularly uniform.

In the paper feed roll 30 of FIG. 3B, the convex portions 16 are arranged on the peripheral surface of the elastic layer 14 along a direction at a predetermined angle of less than 45 ° with respect to the axial direction (an oblique direction close to the axial direction). (In the direction of the arrow). In the paper feed roll 30 in FIG. 3B, a configuration in which a plurality of rows of convex portions 16 in a direction of a predetermined angle are arranged is shown. In the paper feed roll 30 in FIG. 3B, the grooves of the concave portions between the rows of the convex portions 16 are formed in a direction at a predetermined angle of less than 45 ° with respect to the axial direction (an oblique direction close to the axial direction). Since it is formed, the paper dust generated during the conveyance of the paper is easy to move from the convex portion 16 of the roll surface to the groove of the concave portion, and the paper dust is less likely to stay and adhere to the contact portion of the paper, and the friction coefficient due to this The decline is easy to suppress.

In the paper feed roll 40 of FIG. 3C, the convex portions 16 are arranged on the peripheral surface of the elastic layer 14 along a direction at a predetermined angle of more than 45 ° with respect to the axial direction (an oblique direction close to the circumferential direction). Has been. In the paper feed roll 40 of FIG. 3C, a configuration is shown in which a plurality of rows of convex portions 16 that circulate in a predetermined angle direction are arranged on the circumferential surface of the elastic layer 14 (not spiral). ). In the paper feed roll 40 of FIG. 3C, the groove of the concave portion between the rows of the convex portions 16 is formed in a direction at a predetermined angle of more than 45 ° with respect to the axial direction (an oblique direction close to the circumferential direction). 1 is formed, the paper powder moved from the convex portion 16 to the concave groove is rolled from the groove without staying in the groove as the roll rotates, like the concave groove continuous in the circumferential direction of FIG. It is easy to be discharged outside. In other words, the grooves serve as a discharge path for paper dust generated when the paper is transported, and the paper powder is easily discharged out of the roll. Therefore, it is easy to suppress a decrease in the coefficient of friction due to the accumulation of paper powder.

In the paper feed roll 50 of FIG. 3 (d), the circumferential surface of the elastic layer 14 is arranged along a direction with a predetermined angle of more than 45 ° with respect to the axial direction (an oblique direction close to the circumferential direction). In the paper feed roll 50 of FIG. 3D, a configuration in which the convex portions 16 are arranged in a spiral shape in the direction of a predetermined angle on the peripheral surface of the elastic body layer 14 is shown. In the paper feed roll 50 shown in FIG. 3D, the convex portions 16 are arranged on the other side of the paper surface as shown by the dotted line. Similar to the paper feed roll 40 in FIG. 3C, the paper powder moved from the convex portion 16 to the concave groove is easily discharged from the groove to the outside without staying in the groove as the roll rotates. .

Next, the material configuration of the paper feed roll according to the present invention will be described.

As the shaft body 12, a metal core made of a metal solid body, a metal cylinder body hollowed out inside, or the like is used. Examples of the material include stainless steel, aluminum, and iron plated. If necessary, an adhesive, a primer, or the like may be applied on the shaft body 12, and the adhesive, primer, or the like may be made conductive as necessary.

The elastic body layer 14 is formed of an elastic material such as a cross-linked rubber. The material is not particularly limited as long as it is a rubber-like elastic material. For example, known rubber materials such as urethane rubber, hydrin rubber, and silicone rubber can be used.

The elastic layer 14 is preferably conductive or semiconductive. Specifically, the volume resistivity of the elastic layer 14 is preferably in the range of 10 ² to 10 ¹⁰ Ω · cm, 10 ³ to 10 ⁹ Ω · cm, and 10 ⁴ to 10 ⁸ Ω · cm. If the elastic layer 14 has conductivity or semiconductivity, it is easy to suppress adhesion of paper powder by suppressing the surface residual charge of the elastic layer 14 to a low level.

The elastic body layer 14 may contain a conductive agent from the viewpoint of reducing electric resistance. Examples of the conductive agent include an electronic conductive agent and an ionic conductive agent. Examples of the electron conductive agent include carbon black, graphite, c-TiO ₂ , c-ZnO, c-SnO ₂ (c- means conductivity). Examples of the ionic conductive agent include quaternary ammonium salts, borates, and surfactants.

The elastic layer 14 may be appropriately added with various additives as necessary. Additives include lubricants, vulcanization accelerators, anti-aging agents, light stabilizers, viscosity modifiers, processing aids, flame retardants, plasticizers, fillers, dispersants, antifoaming agents, pigments, mold release agents, etc. Can be mentioned.

The thickness of the elastic layer 14 is not particularly limited, and may be set as appropriate within a range of 0.1 to 10 mm.

The elastic body layer 14 can be formed by molding with a molding die using a rubber composition. For example, the shaft body 12 is coaxially installed in the hollow portion of the roll mold, injected with an uncrosslinked rubber composition, heated and cured (crosslinked), and then removed from the mold. The elastic body layer 14 can be formed on the outer periphery of the substrate. As the molding die, it is possible to use a mold in which a concave portion having a shape corresponding to the convex portion 16 is formed on the inner peripheral surface thereof. The convex portion 16 of the elastic layer 14 can be formed, for example, by mold transfer using a molding die.

The recesses on the inner peripheral surface of the molding die can be formed by various recess forming methods such as electric discharge machining, etching, shot blasting, polishing, eutectoid plating, and combinations thereof. In eutectoid plating, uniform resin particles are included in the plating solution, the resin particles are deposited on the inner peripheral surface of the molding die together with the plating metal, and the resin particles appearing on the plating surface are removed. A recess can be formed on the inner peripheral surface.

As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment at all, A various change is possible within the range which does not deviate from the meaning of this invention.

For example, in the above-described embodiment, the paper feed roll 10 is configured to include the shaft body 12 and the elastic body layer 14 formed on the outer periphery of the shaft body 12, and the outermost layer is the elastic body layer 14. However, a surface layer may be provided outside the elastic body layer 14. In this case, the surface layer is the outermost layer, and the elastic body layer 14 is disposed inside the surface layer. The convex portion 16 is formed on the peripheral surface of the elastic layer 14, and the surface layer only needs to be formed with a thickness that ensures surface irregularities due to the plurality of convex portions 16. Moreover, it may replace with formation of a surface layer and a surface modification process may be performed.

Hereinafter, the present invention will be described in detail using examples and comparative examples.

(Examples 1 to 17, Comparative Examples 1 to 4)
An elastic body layer (thickness 3 mm) of a urethane rubber composition was formed on the outer periphery of a core material (φ6, made of SUS304) using a cylindrical mold having a plurality of predetermined recesses on the inner peripheral surface. Thereby, the paper feed roll which has a predetermined some convex part on the surrounding surface of the elastic body layer was obtained. The convex shape, convex arrangement, and convex height are shown in Tables 2 to 4. Table 1 below shows the correspondence between the convex shape and the figure number and the correspondence between the convex array and the figure number. The irregular convex shape was formed by using a cylindrical molding die whose inner peripheral surface was subjected to electric discharge machining. The wavy convex shape was formed using a cylindrical molding die whose inner peripheral surface was polished. Therefore, the irregular convex array is arbitrary, and the wavy convex array is also arbitrary.

As shown in FIG. 4, a glass plate (50 mm × 20 mm × 2 mm) is pressed against the peripheral surface of the obtained paper feed roll 1 with the load shown in Tables 2 to 4, and the contact between the paper feed roll 1 and the glass plate 2 The portion was observed with a microscope (“Laser Microscope VK9500” manufactured by Keyence Corporation). The observation range was 500 μm × 300 μm, and the area ratio of the actual contact portion within the area was calculated. Moreover, the ratio of the contact area per convex part among the whole real contact part was also calculated. FIG. 5 is an observation photograph of the nip portion when a glass plate is pressed against the peripheral surface of the paper feed roll of Example 1. The dark part is the actual contact part, and the light part is the non-contact part.

(Durability evaluation)
The paper feed roll was incorporated into a commercially available copying machine having an FRR type paper feed system, and the paper feed performance was evaluated. Commercially available PPC paper was used as the paper, and 300,000 (300K) papers were passed through to measure the number of occurrences of paper jams due to paper dust. "◎" if the number of occurrences of paper jam is 1 or less, "○" if the number of occurrences of paper jam is 2 or more and 5 or less, and if the number of occurrences of paper jam is 6 or more and 10 or less “XX” was defined as “XX” when the number of occurrences of paper jams was 11 times. In addition, when the paper jam occurred 11 times, the durability evaluation was stopped.

According to the examples and comparative examples, the entire portion in contact with the glass surface when the glass plate is pressed against the peripheral surface of the paper feed roll with a load of 0.5 to 2.3 N per 1 cm in the axial length It can be seen that when the contact area is 1.0 to 15% of the nip area with the glass surface, the conveyance failure of the paper can be suppressed over a long period of time. In Comparative Example 1, the convex shape was adjusted so that the area ratio of the actual contact portion was 0.8%, but the glass plate was pressed with a load of 0.5 to 2.3 N per 1 cm in the axial length. In this case, the convex portion was crushed and it was not possible to adjust to a range of less than 1.0%. In Comparative Examples 2 to 4, since the area ratio of the actual contact portion is in a range exceeding 15%, there are many paper jams, and it is not possible to suppress paper conveyance failure.

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

Claims

A paper feed roll of an electrophotographic apparatus comprising a shaft body and an elastic layer formed on the outer periphery of the shaft body,
The circumferential surface of the elastic layer is provided with a plurality of convex portions that form surface irregularities,
The contact area of the entire portion in contact with the glass surface when the glass plate is pressed against the peripheral surface of the paper feed roll with a load of 0.5 to 2.3 N per 1 cm length in the axial direction is the glass surface. The paper feed roll is 1.0 to 15% of the nip area.
2. The paper feed roll according to claim 1, wherein the ratio of the contact area per convex portion of the entire portion in contact with the glass surface is 0.02 to 10%.
The paper feeding roll according to claim 1 or 2, wherein the plurality of convex portions are regularly arranged on a peripheral surface of the elastic layer.
The paper feeding roll according to any one of claims 1 to 3, wherein the plurality of convex portions includes two types of convex portions having different heights.
The paper feed roll according to claim 4, wherein the height of the low convex portion of the two types of convex portions having different heights is 70 to 80% of the height of the high convex portion.