Toner seal material and method for producing same

Abstract

The present invention relates to a toner seal material (1) for preventing toner leakage from the outer peripheral surface of an end section of a rotating body (23) that carries a powder toner in an image formation device, wherein a surface layer of the toner seal material is formed from a cut pile fiber sheet (5) including pile fibers (2) with an initial elastic modulus (Young's modulus) of 45 cN / decitex or less, and the pile fibers (2) are laid down in one direction. The official moisture content of the pile fibers (2) is preferably 8% or less in a standard state (20°C and 65% RH). The pile fibers (2) are preferably a multifilament yarn and more preferably a diacetate multifilament yarn or a triacetate multifilament yarn. The toner seal material (1) further includes a cushion layer (7).

Description

Toner sealant and its manufacturing method

[0001] The present invention relates to a toner sealant for preventing leakage of powder toner from the outer peripheral surface of a rotating body that carries the toner in an electrophotographic image forming apparatus in the axial direction of the rotating body, and a method for manufacturing the same.

[0002] Traditionally, electrophotographic image forming devices have used powder toner as a developer. Electrophotographic image forming devices are widely used in printers, copiers, facsimile machines, and the like. In electrophotography, an electrostatic latent image is formed on an image carrier such as a photosensitive drum, developed with toner, and then transferred to a recording sheet or the like, where the toner is fixed to the recording sheet or the like. The toner is stored in a container (toner box) of the development unit and moves to the surface of the photosensitive drum or the like while adhering to the outer circumferential surface of the development roller. As the rotating body such as the development roller or photosensitive drum rotates, the toner adheres to its outer circumferential surface. The development roller or photosensitive drum is provided with a leak-proof seal to prevent toner from leaking outward, for example, in the axial direction.

[0003] As prior art related to a sealing material for preventing leakage of fine powder or granular material, Patent Document 1 proposes a cut pile fabric including a pile that contacts the surface of a movable body and a base fabric that supports the pile. Patent Documents 2 and 3 propose the use of a cut pile fabric as a sealing material.

[0004] Japanese Patent Application Laid-Open No. 2006-249383 Japanese Patent Application Laid-Open No. 2005-283729 Japanese Patent Application Laid-Open No. 2003-223047

[0005] However, the conventional sealing materials described above are not durable, and there is a problem in that the toner leaks outward in the axial direction from the outer circumferential surface of the rotating body that carries the powder toner.

[0006] In order to solve the above problems, the present invention provides a toner sealing material and a manufacturing method thereof that can effectively prevent toner leakage from the outer surface of a rotating body carrying powdered toner in the axial direction outward, and that can also contribute to reducing the load on the motor of an image forming device.

[0007] In one aspect, the present invention relates to a toner sealing material for preventing leakage of toner from the outer peripheral surface at the end of a rotating body that carries powdered toner in an image forming apparatus, wherein the surface layer of the toner sealing material is made of a cut pile fiber sheet containing pile fibers having an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less, and the pile fibers are laid flat in one direction.

[0008] In one aspect, the present invention relates to a method for producing the toner sealing material, the method comprising the steps of: producing a bonded double fiber sheet including a bonding yarn and a ground fabric, and cutting the bonding yarn to obtain a cut pile fiber sheet including pile fibers and the ground fabric; impregnating the cut pile fiber sheet with a backing resin and curing it to bond the pile fibers to the ground fabric, thereby performing a backing process; laying the pile fibers in a predetermined direction and simultaneously heat-setting the pile fibers; bonding a cushion layer to the backed cut pile fiber sheet; bonding a double-sided adhesive layer, one side of which is covered with release paper, to the surface of the cushion layer opposite the surface facing the cut pile fiber sheet; and cutting the backed and laid cut pile fiber sheet, the cushion layer, and the double-sided adhesive layer, one side of which is covered with release paper, to a predetermined size, wherein the pile fibers have an initial elastic modulus (Young's modulus) of 45 cN / decitex or less.

[0009] The surface layer of the toner sealing material of the present invention is made of a cut pile fiber sheet containing pile fibers with an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less, and the pile fibers are laid flat in one direction. This prevents the pile fibers from damaging the surface of the rotating sleeve (surface layer of the rotating body), effectively prevents toner from leaking axially outward from the outer circumferential surface of the rotating body that carries the powder toner, and also contributes to reducing the load on the motor of the image forming device.

[0010] FIG. 1 is a schematic cross-sectional view of a toner seal material according to one embodiment of the present invention. FIG. 2 is a schematic cross-sectional view of filaments constituting pile fibers constituting a toner seal material according to one embodiment of the present invention. FIG. 3 is a schematic explanatory view of a process for obtaining a cut pile fiber sheet in the manufacturing process of a toner seal material according to one embodiment of the present invention. FIG. 4 is a schematic explanatory view of a pile-laying process in the manufacturing process of a toner seal material according to one embodiment of the present invention. FIG. 5A is a schematic exploded perspective view showing a toner seal material according to one embodiment of the present invention attached to the outer peripheral surface of the end of a developing roller, and FIGS. 5B and 5C are each a schematic partial enlargement of FIG. 5A. FIG. 6 is a schematic perspective view of filaments constituting pile fibers constituting the toner seal materials according to Examples 1 and 2. FIG. 7 is a schematic perspective view of filaments constituting pile fibers constituting a toner seal material according to Comparative Example 2.

[0011] The toner seal material of the present invention functions to prevent leakage of powdered toner (hereinafter sometimes abbreviated as "toner") from the outer peripheral surface of the end of a rotating body that carries the toner in an image forming apparatus toward the outer axial direction of the rotating body. The surface layer of the toner seal material, i.e., the outermost layer facing the outer peripheral surface of the end of the rotating body, is composed of a cut pile fiber sheet containing pile fibers (hereinafter sometimes referred to as "pile yarns") with an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less. If the initial modulus of elasticity (Young's modulus) of the pile fibers is 45 cN / decitex or less, damage to the surface of the rotating sleeve is suppressed, thereby suppressing toner leakage from the outer peripheral surface of the rotating body toward the outer axial direction due to damage to the sleeve. From the same perspective, the initial modulus of elasticity (Young's modulus) of the pile fibers is preferably 44 cN / decitex or less, more preferably 43 cN / decitex or less. The lower limit of the initial elastic modulus (Young's modulus) of the pile fibers is preferably 5 cN / decitex or more, more preferably 10 cN / decitex or more, and even more preferably 15 cN / decitex or more, from the viewpoint of enabling good toner removal by the pile fibers. The surface of the sleeve is coated with metal plating or resin to impart charge to the toner and to extend its service life. The initial elastic modulus (Young's modulus) can be measured in accordance with JIS L 1013 (initial tensile resistance).

[0012] Polyethylene terephthalate (PET) filaments (multifilament yarns), which have traditionally been used as a material for toner sealants, have a high initial modulus of elasticity (Young's modulus) of approximately 79 to 141 cN / decitex, which causes the surface of the rotating sleeve to be gradually damaged by the cut pile, resulting in deterioration of the sleeve. Furthermore, the initial modulus of elasticity (Young's modulus) of rayon filaments (multifilament yarns) is approximately 60 to 80 cN / decitex, so for the same reason, it is not desirable to use rayon filaments (multifilament yarns) for the pile fibers.

[0013] In the toner seal material of the present invention, the pile fibers are unidirectionally folded. As a result, when the toner seal material is attached to a rotating body so that the tip end of the folded pile fibers is positioned inward in the axial direction of the rotating body relative to the base end, and the longitudinal direction of the pile fibers intersects with the axis of the rotating body, the pile fibers come into contact with the rotating body surface in a reversed pile state. Therefore, toner moving outward in the axial direction of the rotating body is effectively captured by the toner seal material, which is preferable. When the pile fibers are multifilament yarn, toner is captured not only between the pile fibers but also between the filaments (single fibers) constituting the multifilament yarn, thereby more effectively preventing toner leakage. Furthermore, using staple yarn instead of multifilament yarn as the pile fibers is undesirable from the viewpoint of shedding. The number of filaments (single fibers) in the multifilament yarn is preferably 30 to 50, the single fiber fineness is preferably 2.0 to 4.0 decitex, and the total fineness is preferably 60 to 200 decitex.

[0014] The pile length of the pile fibers (pile yarns) of the cut pile fiber sheet is preferably 0.5 to 3.0 mm, more preferably 0.7 to 2.8 mm, and even more preferably 1.0 to 2.5 mm, which can effectively prevent toner leakage.

[0015] When a material with a high official moisture regain, such as rayon, is used as the pile fiber (pile yarn), a high humidity in the usage environment can cause a problem of a high coefficient of friction, increasing rotational torque resistance and increasing the load on the motor. Therefore, in the present invention, the official moisture regain of the pile fiber is preferably 8.0% or less, more preferably 7.5% or less, under standard conditions (20°C, 65% RH) to minimize the influence of the usage environment, and is preferably 2.0% or more, more preferably 2.5% or more, from the viewpoint of suppressing static electricity generation. The above official moisture regain can be measured in accordance with JIS L 1013 (moisture regain and adherent moisture regain).

[0016] The pile fiber (pile yarn) is preferably at least one of diacetate fiber (diacetate multifilament yarn) and triacetate fiber (triacetate multifilament yarn). Diacetate fiber (diacetate multifilament yarn) has an official moisture regain of 6.0 to 7.0% under standard conditions (20°C, 65% RH) and an initial modulus of elasticity (Young's modulus) of 26 to 40 cN / decitex. Triacetate fiber (triacetate multifilament yarn) has an official moisture regain of 3.0 to 4.0% under standard conditions (20°C, 65% RH) and an initial modulus of elasticity (Young's modulus) of 26 to 40 cN / decitex. Diacetate fiber and triacetate fiber are produced from wood pulp by esterifying (oxidizing) the cellulose with acetic acid and then spinning it. The cellulose used in the production of diacetate fibers is cellulose diacetate with an acetylation degree of about 55 wt %, and the cellulose used in the production of triacetate fibers is cellulose triacetate with an acetylation degree of about 61 wt %.

[0017] The cross-sectional shape of the filaments (single fibers) constituting the pile fibers (pile yarns) is preferably an irregular cross-section other than a round cross-section. By making the cross-section of the filaments (single fibers) an irregular cross-section, the area that acts as a wall against the toner increases, making it possible to more effectively prevent toner leakage. If the irregular cross-section is a cocoon-shaped cross-section, the concave and convex portions tend to overlap to form a wall that blocks the movement of toner, making it possible to more effectively prevent toner leakage, which is preferable.

[0018] The mass per unit area of ​​the cut pile fiber sheet is 100 to 480 g / m ２ is preferable, and more preferably 150 to 350 g / m ２ and more preferably 200 to 250 g / m ２ If the mass per unit area is within these ranges, toner leakage can be prevented more effectively.

[0019] The density of the ground weave of the cut pile fiber sheet is preferably 48 to 138 warp threads / inch, more preferably 50 to 110 warp threads / inch, and even more preferably 55 to 90 warp threads / inch. The density is preferably 66 to 135 weft threads / inch, more preferably 75 to 120 weft threads / inch, and even more preferably 85 to 110 weft threads / inch. When the density is within these ranges, toner leakage can be more effectively prevented.

[0020] The thickness of the cut pile fiber sheet when the pile fibers are not flattened is preferably 0.8 to 4.5 mm, because this is suitable as a material for a toner sealant.

[0021] The cut pile fiber sheet can be produced, for example, by cutting the binding yarns of a bonded double layer fiber sheet. The bonded double layer fiber sheet is preferably a bonded double woven fabric or a bonded double knitted fabric. The bonded double knitted fabric may be a bonded double warp knitted fabric or a bonded double weft knitted fabric. In the bonded double layer fiber sheet, the pile fibers are firmly fixed to the ground weave. The bonded double layer fabric may be a warp pile woven fabric or a weft pile woven fabric. Plain weave, twill weave, satin weave, etc. are preferred as the ground weave of these fabrics.

[0022] The fiber material used for the ground weave of the cut pile fiber sheet may be any material, including synthetic fibers such as polyester, nylon, and polypropylene; regenerated fibers such as rayon, diacetate, or triacetate fibers; and natural fibers such as cotton, linen, and wool. Among these, the yarns constituting the ground weave are preferably polyester multifilament yarns, diacetate multifilament yarns, or triacetate multifilament yarns, more preferably polyethylene terephthalate multifilament yarns, diacetate multifilament yarns, or triacetate multifilament yarns, and even more preferably diacetate multifilament yarns or triacetate multifilament yarns. The ground weave is not particularly limited and may be the same as conventionally known yarns. However, from the viewpoint of maintaining the shape of the cut pile fiber sheet, it is preferable that the total fineness of the multifilament yarns constituting the ground weave and the total fineness of the binding yarns (multifilaments) that will be cut to form pile fibers are equal, or that the binding yarns be lower than the multifilament yarns constituting the ground weave. In order to efficiently capture toner with the pile fibers, it is preferable that the thickness of each filament constituting the multifilament yarn (single fiber fineness) of each yarn constituting the ground structure is equal to that of the binding yarn, or that the binding yarn is thinner than that of each yarn of the ground structure. Furthermore, the official moisture regain of each yarn constituting the ground structure under standard conditions (20°C, 65% RH) may be significantly smaller than that of the pile fibers (pile yarns), and is usually 0 to 8.0%, preferably 0 to 3.0%.

[0023] From the viewpoint of thickness adjustment, the toner sealant preferably further includes a cushion layer fixed to the back side (ground fabric side) of the cut pile fiber sheet. The cushion layer is preferably an elastic layer, a foam layer, or a nonwoven fabric layer. The toner sealant including the cushion layer is convenient as a sealing material for the outer peripheral surface of the end of the rotating body. The cushion layer is preferably a nonwoven fabric layer combined with the cut pile fiber sheet by needle punching. In this case, the backed cut pile fiber sheet and the cushion layer (nonwoven fabric layer) can be combined without using double-sided tape, adhesive, or the like, thereby preventing the occurrence of wrinkles in the toner sealant due to differences in curvature between the backed cut pile fiber sheet and the cushion layer.

[0024] From the viewpoint of ease of installation within the image forming apparatus, the toner sealant preferably further includes a double-sided adhesive layer, such as double-sided tape, affixed to the surface of the cushion layer opposite the cut pile fiber sheet side. A release liner is preferably provided on the surface of the double-sided adhesive layer opposite the cushion layer side. This allows the toner sealant to be easily installed by peeling off the release liner and attaching it to a predetermined position within the image forming apparatus.

[0025] Next, an example of a method for producing the toner sealing material of the present invention will be described. The example of a method for producing the toner sealing material of the present invention includes the following steps (1) to (4).

[0026] (1) Manufacturing Process of Cut Pile Fiber Sheet In this process, a bonded double fiber sheet is manufactured using diacetate or triacetate multifilament yarns as the binding yarns, and the binding yarns are cut to obtain a cut pile fiber sheet.

[0027] (2) Backing Processing Step: In this step, the cut pile fiber sheet is impregnated with a backing resin or the like and cured to firmly bond the pile fibers to the ground weave of the bonded double fiber sheet. The bonding yarns are fixed to the ground weave using, for example, a backing resin. Acrylic resin is a suitable backing resin. The cut pile fiber sheet is impregnated with the backing resin by, for example, contacting the back surface of the cut pile fiber sheet with a roll to which the required amount of resin has been applied, thereby transferring the resin to the back surface of the cut pile fiber sheet. The cut pile fiber sheet with the transferred resin is then passed through a dryer to cure the resin. Alternatively, a double-sided adhesive layer (not shown), one side of which is covered with release paper, may be fixed to the adhesive layer 6 (see FIG. 1) made of the backing resin in the backed cut pile fiber sheet, and the double-sided adhesive layer may be used to bond the backed cut pile fiber sheet to a cushioning layer.

[0028] (3) Pile-laying Process In this process, for example, a thermal calendering process is performed by passing a cut pile fiber sheet between calender rolls while applying heat and pressure, thereby laying the pile fibers (raised fibers) in a certain direction and simultaneously heat-setting them. This improves the toner-blocking effect of the pile fibers. The temperature of the thermal calender is preferably 80 to 150°C, for example. Pile-laying is usually performed after backing processing is performed on the cut pile fiber sheet to firmly fix the binding yarns to the ground fabric with a backing resin. It is preferable to place a calender roll ahead of the roll to which the required amount of resin has been applied, since this allows the backing processing and pile-laying processing to be performed in this order in a single flow.

[0029] (4) Step of Applying Cushion Layer and Double-Sided Adhesive Layer Simultaneously with or separately from the pile-laying step, a cushioning material is laminated and bonded to the backing-treated cut pile fiber sheet to form the cushioning layer 7. The cushioning material is bonded to the cut pile fiber sheet, for example, by a double-sided adhesive layer 10 (see FIG. 1) bonded to the adhesive layer 6. Examples of the cushioning layer 7 include an elastic layer, a foam layer, and a nonwoven fabric layer. In addition, a double-sided adhesive layer 8, one side of which is covered with a release paper 9, is bonded to the back surface of the cushioning layer 7. The double-sided adhesive layer 8 may be bonded to the cushioning layer 7 before or after the cushioning material is bonded to the cut pile fiber sheet.

[0030] (5) Cutting Step The long laminate obtained through the above step (4) and including the backing-processed cut pile fiber sheet 5, the cushion layer 7, and the double-sided adhesive layer 8, one side of which is covered with release paper 9, is melt-cut into a predetermined size using a laser cutter or the like. This is to make the size suitable for attachment to a rotating body.

[0031] In one example of the manufacturing method for the toner seal material of the present invention, a cushion layer is fixed to a backed cut pile fiber sheet using a double-sided adhesive layer, and then the pile is laid. However, the cushion layer and the backed cut pile fiber sheet may be joined simultaneously with or after the pile laying. Furthermore, the cushion layer may be fixed to the backed cut pile fiber sheet by using a nonwoven fabric as the cushion layer, or by needle-punching the fibers of the ground structure of the backed cut pile fiber sheet and the fibers constituting the nonwoven fabric. When the cushion layer is fixed to the backed cut pile fiber sheet by needle-punching, it is preferable to perform the fixation before laying the pile fibers to prevent the pile fibers from becoming entangled in the entanglement.

[0032] In view of the above, one aspect of the method for producing a toner sealant of the present invention includes the following: producing a bonded double fiber sheet including a binding yarn and a ground structure, and cutting the binding yarn to obtain a cut pile fiber sheet including pile fibers and the ground structure; impregnating the cut pile fiber sheet with a backing resin and curing it to bond the pile fibers to the ground structure, thereby performing a backing process; laying the pile fibers in a predetermined direction and simultaneously heat-setting the pile fibers; bonding a cushion layer to the backed cut pile fiber sheet; bonding a double-sided adhesive layer, one side of which is coated with release paper, to the surface of the cushion layer opposite the surface facing the cut pile fiber sheet; and cutting the laminate (a long toner sealant) including the backed and laid cut pile fiber sheet, the cushion layer, and the double-sided adhesive layer, one side of which is coated with release paper, to a predetermined size. In this manufacturing method, the cushion layer and the backed cut pile fiber sheet may be bonded together after or simultaneously with the laying process. The cushion layer may be bonded to the backed cut pile fiber sheet by adhesion using a double-sided adhesive layer, or by using a nonwoven fabric as the cushion layer and entangling the fibers of the ground structure of the backed cut pile fiber sheet with the fibers of the nonwoven fabric by needle punching. When the cushion layer is bonded to the backed cut pile fiber sheet by needle punching, it is preferable to perform the bonding before laying the pile fibers to prevent the pile fibers from becoming entangled in the entanglement.

[0033] The toner sealing material of the present invention may be provided to the market in a state cut to a size suitable for attachment to a rotating body, or may be provided to the market in the form of a long laminate before cutting. The toner sealing material of the present invention includes not only a toner sealing material cut to a size suitable for attachment to a rotating body, but also the long laminate.

[0034] The following description will be made with reference to the drawings. In the following drawings, the same reference numerals indicate the same parts. FIG. 1 is a schematic cross-sectional view of a toner seal material 1 according to one embodiment of the present invention. In this toner seal material 1, pile fibers 2 are laid flat in a certain direction. The pile fibers 2 are fixed by a ground fabric 5 including warp yarns 3a and 3b and weft yarns 4. The pile fibers 2 and the ground fabric 5 are further firmly fixed by an adhesive layer 6 containing a backing resin impregnated in the ground fabric. A cushion layer 7 is fixed to the back surface of the adhesive layer 6 via a double-sided adhesive layer 10. A double-sided adhesive layer 8 is fixed to the back surface of the cushion layer 7. The back surface of the double-sided adhesive layer 8 is covered with a release paper layer 9.

[0035] It is preferable that the direction of pile formation of the pile fibers 2 (the direction from the base end to the tip end of the pile fibers) is opposite to the direction of rotation of the rotating developing roller 23. In this case, the pile fibers 2 come into contact with the sleeve of the developing roller 23 in a reversed pile state. Therefore, toner on the sleeve (on the outer circumferential surface of the developing roller 23) that is adjacent to the toner seal material 1 is effectively captured by the pile fibers 2. As a result, toner leakage from the outer circumferential surface of the developing roller carrying the toner in the direction of the axis 24a can be effectively prevented.

[0036] 2 is a schematic cross-sectional view of a filament (single fiber) constituting the pile fiber 2 (multifilament yarn) of a toner sealing material according to one embodiment of the present invention. The cross section of the filament (single fiber) constituting the pile fiber 2 is cocoon-shaped. The cocoon-shaped cross section provides a large area that acts as a wall against toner moving outward in the direction of the axis 24a from the outer circumferential surface of the developing roller 23, thereby enabling toner to be captured effectively.

[0037] 3 is a schematic diagram illustrating the manufacturing process of a cut pile fiber sheet 14 according to one embodiment of the present invention. In this manufacturing process, a bonded double woven fabric 13 is produced, which is a plain weave ground fabric including ground warp yarns 3a, 3b and ground weft yarns 4, and is composed of binding yarns 12. The binding yarns 12 are then cut with a knife 15 to obtain the cut pile fiber sheet 14.

[0038] Next, the ground weave is impregnated with a backing resin to firmly bond the pile fibers 2 to the ground weave fabric 5. A double-sided adhesive layer 10 with a single-sided release paper is fixed to the side of the adhesive layer 6 (see Figure 1) containing the backing resin, opposite the cut pile fiber sheet 5 side, to obtain a backed cut pile fiber sheet with a double-sided adhesive layer.

[0039] Figure 4 is a schematic diagram illustrating the pile-laying process for one embodiment of the present invention. A raw roll 17 is a raw roll of a cut pile fiber sheet with a double-sided adhesive layer that has been backed. A lay-laying device 16 supplies the backed cut pile fiber sheet with a double-sided adhesive layer from the raw roll 17 while peeling off the release paper (not shown). A cushioning material for the cushion layer 7 (see Figure 1) is supplied from the raw roll 18. These materials are passed between heat calender rolls 19a and 19b, whereby the pile fibers 2 are laid in the direction opposite to the forward direction and simultaneously heat-set. The resulting laminate is wound onto a winder 20.

[0040] Next, the laminate is pulled out from the roll 20, and a double-sided adhesive layer 8 having a release paper layer 9 on one side is attached to the cushion layer 7 to obtain a long toner seal material (laminate).

[0041] FIG. 5A is a schematic exploded perspective view showing a toner seal material according to one embodiment of the present invention attached to the outer peripheral surface of the end of a developing roller, and FIGS. 5B and 5C are schematic partial enlarged views of FIG. 5A. The toner seal materials 22a and 22b function as side seals for both end portions 23a and 23b of the developing roller 23. These toner seal materials 22a and 22b are in close contact with the outer peripheral surface of the developing roller 23 and are positioned to prevent toner leakage along the axis 24a. The outermost layer of the toner seal materials 22a and 22b facing the outer peripheral surface of the end of the developing roller 23 is composed of a cut pile fiber sheet containing pile fiber 2 (multifilament yarn) with an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less. Arrows 38a and 38b indicate the direction of toner leakage. Arrow 24b indicates the direction of rotation of the developing roller 23. The developing roller 23 is mounted in an opening 27 facing the developing roller 23 in a developing unit 21 of an electrophotographic image forming apparatus. From the perspective of application to the developing roller 23 that carries toner in an image forming apparatus, the toner seal materials 22a and 22b preferably have a length of 10 to 50 mm, a width of 3 to 15 mm, and a thickness of 2.0 to 4.5 mm. The toner seal materials 22a and 22b are rectangular in shape. In FIGS. 5B and 5C, 2a denotes the base end of the pile fibers, and 2b denotes the tip end of the pile fibers. In FIG. 5B, X denotes the longitudinal direction of the toner seal material 22a, and in FIG. 5C, Y denotes the longitudinal direction of the toner seal material 22b. The pile direction of the pile fibers 2 is preferably inclined with respect to the longitudinal directions X and Y of the toner seal materials 22a and 22b. The pile direction of the pile fibers 2 constituting the toner seal material 22a is inclined in the longitudinal direction X in opposite directions to the pile direction of the pile fibers 2 constituting the toner seal material 22b in the longitudinal direction Y. The pile fibers 2 of the toner seal materials 22a and 22b are in a reversed pile state when they come into contact with the surface of the rotating developing roller 23. The inclination angle θ of the filaments (single fibers) constituting the pile fibers 2 with respect to the longitudinal directions X and Y is preferably 30 to 90°, more preferably 45 to 60°, from the viewpoint of effectively preventing toner leakage from the outer peripheral surface of the developing roller 23 outward in the axial direction. The pile direction of the pile fibers may be the same as the longitudinal direction of the toner seal material.

[0042] The toner seal materials 22a and 22b are attached to the housing 25 of the developing unit 21 before the developing roller 23. The developing unit 21 is also provided with a blade 26, which is a toner regulating member. The thickness of the toner layer is adjusted by the blade 26 and maintained at a certain level or less. The rotating shaft 24 of the developing roller 23 is rotatably supported by the housing 25 of the developing unit 21, and toner is supplied to the developing roller 23 from inside the developing unit 21.

[0043] In this specification, the upper and lower limits of each numerical range can be combined in any combination, and all such combinations are considered to be preferred numerical ranges described in this specification.

[0044] The present application further discloses the following inventions.

[0045] [1] A toner sealing material for preventing toner leakage from the outer peripheral surface of the end of a rotating body that carries powdered toner in an image forming apparatus, wherein the surface layer of the toner sealing material is made of a cut pile fiber sheet containing pile fibers with an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less, and the pile fibers are laid flat in one direction. [2] The toner sealing material according to [1], wherein the pile fibers have an official moisture regain of 8.0% or less under standard conditions (20°C, 65% RH). [3] The toner sealing material according to [1] or [2], wherein the pile fibers are at least one fiber selected from the group consisting of diacetate fibers and triacetate fibers. [4] The toner sealing material according to any one of [1] to [3], wherein the pile fibers are multifilament yarns. [5] The toner sealing material according to [4], wherein the multifilament yarns have a single fiber fineness of 2.0 to 4.0 decitex and a number of single fibers constituting the multifilament yarns is 30 to 50. [6] The toner seal material according to any one of [1] to [5], wherein the pile length of the pile fibers is 0.5 to 3.0 mm. [7] The mass per unit area of ​​the cut pile fiber sheet is 100 to 480 g / m ２[8] The toner sealing material according to any one of [1] to [6], wherein the cross section of the filament (single fiber) constituting the pile fiber is an irregular cross section. [9] The toner sealing material according to any one of [1] to [8], wherein the toner sealing material further includes a cushion layer.

[10] The toner sealing material according to [9], wherein the toner sealing material further includes a double-sided adhesive layer with a single-sided release paper attached to the surface of the cushion layer opposite the surface facing the cut pile fiber sheet.

[11] A method for using the toner sealing material according to any one of [1] to

[10] , wherein the toner sealing material is attached to the rotating body so that the tip side of the pile fibers laid flat is located inward in the axial direction of the rotating body relative to the base side, the longitudinal direction of the pile fibers intersects with the axial direction of the rotating body, and the surface layer is in contact with the surface of the rotating body.

[0046] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The physical properties in the examples were measured by methods commonly used in the textile industry. The "parts" and "%" in the examples are based on mass. The following examples and comparative examples were evaluated as follows.

[0047] [Measurement of rotational torque current value] The toner seal materials of Example 1 and Comparative Examples 1 to 3 were attached to both ends of the sleeve of a developing roller with a diameter of 10.8 mm, and then the sleeve was rotated 30,000 times. During this time, printing was performed on A4-sized paper using color toner with a particle size of approximately 8 μm. The torque current value during rotation of the sleeve was measured, and the average current value during measurement is shown in Table 1 as the rotational torque current value (mA).

[0048] [Observation of Sleeve Surface] After the above [Measurement of Rotational Torque Current Value], the sleeve was removed from the image forming apparatus, and the surface of the sleeve was visually observed under a microscope (200x magnification), and the surface condition was evaluated according to the following criteria: (Evaluation criteria for sleeve surface condition) A: No scratches were observed. B: Scratches were observed in 1 to 5 places. C: Scratches were observed in 6 places or more.

[0049] [Toner Leakage Test] After the above [Measurement of Rotational Torque Current Value], the penetration rate (%) of the toner in the width direction of the toner seal material (directions of arrows 38a and 38b in FIG. 5) was measured. The larger the penetration rate (%), the more likely toner leakage occurs, and the smaller the value, the more effectively toner leakage can be suppressed. The penetration rate (%) can be calculated using the following formula: Penetration rate (%) = (width direction length of the part of the toner seal material into which the toner has penetrated ÷ total width direction length of the toner seal material) × 100

[0050] Example 1: A double-layer velvet loom was used to produce a warp pile weave co-knitted double-layer fabric. A rapier-type co-knitted double-layer loom was used to produce the co-knitted double-layer fabric 13 shown in Figure 3. The ground warp and weft yarns were made of polyethylene terephthalate multifilament yarn (manufactured by Toray Industries, Inc., total fineness: 135 decitex, number of filaments: 30, initial modulus of elasticity (Young's modulus): 80 cN / decitex, official moisture regain: 0.4% at standard conditions (20°C, 65% RH)). The pile yarn was made of diacetate multifilament yarn (manufactured by Eastman Chemical Co., total fineness: 135 decitex, number of filaments: 35, initial modulus of elasticity (Young's modulus): 40 cN / decitex, official moisture regain: 6.5% at standard conditions (20°C, 65% RH)). Next, the binding yarns 12 were cut with a knife 15 to obtain a cut pile fiber sheet 14 having a thickness of 2.2 mm. The mass per unit area (basis weight) of the obtained cut pile fiber sheet 14 was 230 g / m ２ The pile fiber length (pile length) was 2.0 mm, and the density of the ground weave was 80 threads / inch in the warp direction and 100 threads / inch in the weft direction. Figure 6 shows a schematic perspective view of the filaments (single fibers) that make up the pile yarn, and the cross-sectional shape of the filaments is approximately cocoon-shaped.

[0051] Next, the cut pile fiber sheet 14 was impregnated with acrylic resin and cured to bond the pile fibers to the ground fabric, yielding a backed cut pile fiber sheet. Next, Nitto HJ-9150 double-sided tape was applied to the side of the acrylic resin-containing adhesive layer 6 opposite the cut pile fiber sheet 5 side, yielding a backed cut pile fiber sheet with a double-sided adhesive layer.

[0052] 4 is a schematic diagram illustrating a pile-laying process for one embodiment of the present invention. A raw roll 17 is a raw roll of cut pile fiber sheet with a backing-treated double-sided adhesive layer. A pile-laying device 16 supplies a cut pile fiber sheet impregnated with a backing resin from the raw roll 17 while peeling the release paper (not shown) from the double-sided adhesive layer 10 (see FIG. 1 ). A urethane foam cushion layer 7 (PORON LE20, 1 mm thick, manufactured by Inoac Corporation) is supplied from the raw roll 18. These layers are stacked and passed between heat calendar rolls 19a and 19b at 80°C. The pile fibers 2 are laid in the direction opposite to the running direction of the cut pile fiber sheet 14, and simultaneously heat-set. Next, double-sided tape (Nitto 500) was attached to the cushion layer 7, and the long toner seal material having the configuration shown in Fig. 1 was melt-cut with a laser cutter to obtain a toner seal material having a length of 20 mm, a width of 5 mm, and a thickness of 3.3 mm. The angle of the pile fiber direction relative to the longitudinal direction of the obtained toner seal material was within a range of 45 to 60 degrees.

[0053] (Example 2) The cut pile fiber sheet prepared in Example 1 and having a backing was used, and a sheet having a basis weight of 135 g / m was applied to the back surface. ２A 1.2 mm thick nonwoven fabric composed of 100% polyethylene terephthalate (manufactured by Toray, total fineness: 2.2 decitex, fiber length: 51 mm) was needle-punched to form a cushion layer, and double-sided tape (Nitto 500) was attached to the nonwoven fabric. The resulting long toner seal material was then melt-cut with a laser cutter to obtain a toner seal material measuring 20 mm in length, 5 mm in width, and 3.3 mm in thickness. The pile fibers were flattened by passing the material through a pair of heat calender rolls at 80°C after needle-punching and before attaching the double-sided tape.

[0054] Comparative Example 1 A pile yarn having a mass per unit area (basis weight) of 235 g / m was produced in the same manner as in Example 1, except that a single yarn of polyethylene terephthalate multifilament yarn (manufactured by Toray Industries, Inc., total fineness: 135 decitex, number of filaments: 30, initial modulus of elasticity (Young's modulus): 80 cN / decitex, official moisture regain: 0.4% under standard conditions (20°C, 65% RH)) was used as the pile yarn. ２ A cut pile fiber sheet having a thickness of 2.2 mm and a base density of 80 threads / inch in the warp direction and 100 threads / inch in the weft direction was prepared, and a toner seal material having a length of 20 mm, a width of 5 mm and a thickness of 3.3 mm was obtained.

[0055] Comparative Example 2 A pile yarn having a mass per unit area (basis weight) of 240 g / m was produced in the same manner as in Example 1, except that a single yarn of rayon multifilament yarn (manufactured by Jilin Chemical Fiber Co., Ltd. and Toray Industries, Inc., total fineness: 135 decitex, number of filaments: 40, initial modulus of elasticity (Young's modulus): 60 cN / decitex, official moisture regain: 11.0% under standard conditions (20°C, 65% RH)) was used as the pile yarn. ２ A cut pile fiber sheet with a thickness of 2.2 mm and a ground density of 80 threads / inch in the warp and 100 threads / inch in the weft was prepared, and a toner seal material with a length of 20 mm, a width of 5 mm, and a thickness of 3.3 mm was obtained. Figure 7 shows a schematic perspective view of the filaments (single fibers) that make up the pile yarn, and the cross-sectional shape of the filament is approximately cocoon-shaped.

[0056] (Comparative Example 3) A pile warp having a mass per unit area (basis weight) of 220 g / m was produced in the same manner as in Example 1, except that a single yarn of nylon multifilament yarn (manufactured by Nirit Co., Ltd., total fineness: 110 decitex, number of filaments: 48, initial modulus of elasticity (Young's modulus): 50 cN / decitex, official moisture regain: 4.5% under standard conditions (20°C, 65% RH)) was used as the pile warp yarn. ２ A cut pile fiber sheet having a thickness of 2.2 mm and a base density of 80 threads / inch in the warp direction and 100 threads / inch in the weft direction was prepared, and a toner seal material having a length of 20 mm, a width of 5 mm and a thickness of 3.3 mm was obtained.

[0057]

[0058] As shown in Table 1, when the toner sealing materials of Examples 1 and 2 were used, the current value of the rotational torque was lower than when the toner sealing materials of Comparative Examples 1 to 3 were used, and therefore it was confirmed that the load on the motor that rotates the developing roll was less. Furthermore, when the toner sealing material of Example 1 was used, the number of scratches on the sleeve surface was significantly fewer than when the toner sealing materials of Comparative Examples 1 to 3 were used. Furthermore, when the toner sealing materials of Examples 1 and 2 were used, the toner penetration rate (%) in the width direction of the toner sealing material was smaller than when the toner sealing materials of Comparative Examples 1 to 3 were used, and it was confirmed that toner leakage from the outer peripheral surface of the rotating body that carries powder toner in the axial direction could be effectively prevented.

[0059] The nonwoven fabric for toner seals of the present invention is useful as a material for sealing materials to prevent leakage of toner in electrophotographic image forming apparatuses that use powder toner.

[0060] REFERENCE SIGNS LIST 1 toner seal material 2 pile fiber 2a base end of pile fiber 2b tip end of pile fiber 3a, 3b warp yarn 4 weft yarn 5 ground weave fabric 6 adhesive layer 7 cushion layer 8, 10 double-sided adhesive layer 9 release paper layer 12 binding yarn 13 binding double fiber fabric 14 cut pile fiber sheet 15 knife 16 pile-setting device 17, 18, 20 raw fabric roll 19a, 19b heat calender roll 22a, 22b toner seal material 23 developing roller 24 rotating shaft 24a axis of developing roller 25 housing 26 blade 27 opening 28a, 28b toner leakage direction A, 24b rotation direction of developing roller

Claims

1. A toner sealant for preventing toner leakage from the outer peripheral surface of the end of a rotating body that carries powder toner in an image forming device, wherein the surface layer of the toner sealant is made of a cut pile fiber sheet containing pile fibers with an initial modulus of elasticity (Young's modulus) of 45 cN / decitex or less, and the pile fibers are laid flat in one direction.

2. The toner sealant according to claim 1, wherein the pile fibers have an official moisture regain of 8.0% or less under standard conditions (20°C, 65% RH).

3. The toner sealing material according to claim 1 or 2, wherein the pile fibers are at least one selected from the group consisting of diacetate fibers and triacetate fibers.

4. A toner sealant according to any one of claims 1 to 3, wherein the pile fibers are multifilament yarns.

5. The toner sealant according to claim 4, wherein the multifilament yarn has a single fiber fineness of 2.0 to 4.0 decitex and a number of constituent fibers of 30 to 50.

6. The toner sealant according to any one of claims 1 to 5, wherein the pile length of the pile fibers is 0.5 to 3.0 mm.

7. The mass per unit area of ​​the cut pile fiber sheet is 100 to 480 g / m ２ 7. The toner sealing material according to claim 1, wherein the toner sealing material is a toner sealant.

8. A toner sealing material according to claim 4 or 5, wherein the cross section of the filament (single fiber) constituting the pile fiber is an irregular cross section.

9. The toner sealant according to any one of claims 1 to 8, further comprising a cushion layer.

10. The toner sealant according to claim 9, further comprising a double-sided adhesive layer with a release paper on one side adhered to the surface of the cushion layer opposite the surface on the cut pile fiber sheet side.

11. A method for producing a toner sealing material, comprising: producing a bonded double fiber sheet including a bonding yarn and a ground fabric, and cutting the bonding yarn to obtain a cut pile fiber sheet including pile fibers and the ground fabric; backing the cut pile fiber sheet by impregnating the cut pile fiber sheet with a backing resin and curing it to bond the pile fibers to the ground fabric; laying the pile fibers in a predetermined direction and simultaneously heat-setting them; bonding a cushion layer to the backed cut pile fiber sheet; bonding a double-sided adhesive layer, one side of which is covered with release paper, to the surface of the cushion layer opposite the surface facing the cut pile fiber sheet; and cutting to a predetermined size a laminate comprising the backed and laid cut pile fiber sheet, the cushion layer, and the double-sided adhesive layer, one side of which is covered with release paper; wherein the pile fibers have an initial elastic modulus (Young's modulus) of 45 cN / decitex or less.

12. The method for producing a toner seal material according to claim 10, wherein the binding yarn is a diacetate multifilament yarn or a triacetate multifilament yarn.

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