Sliding member, fixing device, and image forming apparatus

Abstract

A sliding member, a fixing device, and an image forming apparatus, in which a plurality of first grooves are provided at a center portion of a sliding surface in a width direction of the first grooves at intervals in the width direction of the first grooves, an angle formed between the first grooves and the sliding direction being 45-90 DEG, and an angle formed between the first grooves and the sliding direction being 45-90 DEG, are provided at a center portion of the sliding surface in the width direction of the first grooves. When a cut surface obtained by cutting the sliding member in a direction perpendicular to the first groove and in a thickness direction is observed, an angle (A) formed by a wall surface of the first groove on the downstream side in the sliding direction of the first groove and the sliding direction is 21-45 DEG.

Description

Technical Field

[0001] The present invention relates to a sliding member, a fixing device, and an image forming apparatus. Background Art

[0002] For example, Patent Document 1 discloses "a sliding member for a fixing device, which includes: a rotating member; a belt member that rotates together with the rotating member; and a clamping forming member that forms a clamping portion between the rotating member via the belt member. In a fixing device that passes paper through the clamping portion, between the belt member and the clamping forming member, characterized in that the sliding member has a sliding contact surface that slidably contacts the inner peripheral surface of the belt member on a surface on the side that slides on the inner peripheral surface of the belt member, i.e., a sliding surface, and a groove that is recessed from the sliding contact surface, i.e., a recessed groove. The recessed groove has an inclined surface that becomes shallower in the sliding downstream direction of the belt member with respect to the sliding contact surface at the bottom of the groove."

[0003] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2022-156529 Summary of the Invention

[0004] An object of the present invention is to provide a sliding member that has low sliding resistance and excellent maintainability of low sliding resistance compared to a sliding member in which a plurality of first grooves are provided at intervals in the width direction of the first grooves at the center in the width direction of the sliding surface, the angle formed by the first grooves and the sliding direction is 45° or more and 90° or less, and when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first grooves and in the thickness direction, the angle A formed by the wall surface of the first groove on the sliding downstream side among the plurality of first grooves and the sliding direction is less than 21° or more than 45°.

[0005] Means for solving the above problems include the following methods.

[0006] <1>

[0007] A sliding member, wherein

[0008] a plurality of first grooves are provided at intervals in the width direction of the first grooves at the center in the width direction of the sliding surface,

[0009] the angle formed by the first grooves and the sliding direction is 45° or more and 90° or less,

[0010] when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first grooves and in the thickness direction, the angle A formed by the wall surface of the first groove on the sliding downstream side among the first grooves and the sliding direction is 21° or more and 45° or less.

[0011] <2>

[0012] The sliding member according to <1>, wherein,

[0013] When observing the cut surface obtained by cutting the sliding member along the direction perpendicular to the first groove and in the thickness direction, the angle B formed by the wall surface of the first groove on the upstream side in the sliding direction in the first groove and the sliding direction is 10° or more and 35° or less.

[0014] <3>

[0015] The sliding member according to <1> or <2>, wherein,

[0016] As the first groove, a plurality of grooves in the width direction of the sliding surface are provided at intervals in the sliding direction.

[0017] <4>

[0018] The sliding member according to any one of <1> to <3>, wherein,

[0019] A plurality of second grooves are provided at intervals in the width direction of the second groove at the center in the width direction of the sliding surface,

[0020] The angle formed by the first groove and the second groove is 45° or more and 90° or less.

[0021] <5>

[0022] The sliding member according to <4>, wherein,

[0023] The first groove is continuously provided along a direction orthogonal to the sliding direction, and the second groove is intermittently provided along the sliding direction.

[0024] <6>

[0025] The sliding member according to any one of <1> to <5>, wherein,

[0026] The cross-sectional area of the first groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction.

[0027] <7>

[0028] The sliding member according to <4>, wherein,

[0029] The cross-sectional area of the second groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction.

[0030] <8>

[0031] The sliding member according to any one of <1> to <7>, wherein,

[0032] The angle A is 23° or more and 40° or less.

[0033] <9>

[0034] The sliding member according to <2>, wherein,

[0035] The angle B is 15° or more and 30° or less.

[0036] <10>

[0037] The sliding member according to <2>, wherein,

[0038] The absolute value of the difference between the angle A and the angle B is 5° or more and 30° or less.

[0039] <11>

[0040] The sliding member according to <10>, wherein,

[0041] The absolute value of the difference between the angle A and the angle B is 7° or more and 25° or less.

[0042] <12>

[0043] A fixing device, comprising:

[0044] A first rotating body;

[0045] A second rotating body disposed in contact with the first rotating body;

[0046] A pressing member disposed on the inner peripheral surface of the second rotating body and pressing the second rotating body from the inner peripheral surface of the second rotating body against the first rotating body;

[0047] The sliding member according to any one of <1> to <11>, interposed between the inner peripheral surface of the second rotating body and the pressing member; and

[0048] A lubricant interposed between the inner peripheral surface of the second rotating body and the sliding member.

[0049] <13>

[0050] An image forming apparatus, comprising:

[0051] An image holding body;

[0052] A latent image forming device that forms a latent image on the surface of the image holding body;

[0053] A developing device that develops the latent image into a toner image using a developer;

[0054] A transfer device that transfers the developed toner image onto a recording medium; and

[0055] <12>The fixing device described above fixes the toner image on the recording medium.

[0056] Advantages of the Invention

[0057] According to the invention according to <1> or <3>, there is provided a sliding member as follows: It is provided at the center in the width direction of the sliding surface at intervals in the width direction of a plurality of first grooves, the angle formed by the first grooves and the sliding direction is 45° or more and 90° or less, and when observing the cut surface obtained by cutting the sliding member along the direction perpendicular to the first grooves and in the thickness direction, the sliding member has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the angle A between the wall surface of the first groove on the downstream side in the sliding direction in the first groove and the sliding direction is less than 21° or exceeds 45°.

[0058] According to the invention according to <2>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the angle B between the wall surface of the first groove on the upstream side in the sliding direction in the first groove and the sliding direction is less than 10° or exceeds 35° when observing the cut surface obtained by cutting the sliding member along the direction perpendicular to the first grooves and in the thickness direction.

[0059] According to the invention according to <4>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where a plurality of second grooves having an angle of 45° or more and 90° or less with the first grooves are not provided at intervals in the width direction of the sliding surface at the center in the width direction of the second grooves.

[0060] According to the invention according to <5>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the first grooves are not continuously provided along the direction perpendicular to the sliding direction or the second grooves are not intermittently provided along the sliding direction.

[0061] According to the invention according to <6>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the cross-sectional area of the first groove does not change from the upstream side to the downstream side in the sliding direction.

[0062] According to the invention according to <7>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the cross-sectional area of the second groove does not change from the upstream side to the downstream side in the sliding direction.

[0063] According to the invention according to <8>, there can be provided a sliding member as follows: It has a lower sliding resistance and better maintainability of the lower sliding resistance compared to the case where the angle A is less than 23° or exceeds 40°.

[0064] According to the invention related to <9>, it is possible to provide a sliding member having low sliding resistance and excellent maintainability of low sliding resistance as compared with the case where the angle B is less than 15° or more than 30°.

[0065] According to the invention related to <10>, it is possible to provide a sliding member having low sliding resistance and excellent maintainability of low sliding resistance as compared with the case where the absolute value of the difference between the angle A and the angle B is less than 5° or more than 30°.

[0066] According to the invention related to <11>, it is possible to provide a sliding member having low sliding resistance and excellent maintainability of low sliding resistance as compared with the case where the absolute value of the difference between the angle A and the angle B is less than 7° or more than 25°.

[0067] According to the invention related to <12> or <13>, there is provided a fixing device including a sliding member having low sliding resistance and excellent maintainability of low sliding resistance as compared with a sliding member in which a plurality of first grooves are provided at intervals in the width direction of the first groove at the center in the width direction of the sliding surface, the angle formed by the first groove and the sliding direction is 45° or more and 90° or less, and when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first groove and in the thickness direction, the angle A formed by the wall surface of the first groove on the downstream side in the sliding direction among the plurality of first grooves and the sliding direction is less than 21° or more than 45°. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] The embodiments of the present invention will be described in detail with reference to the following drawings.

[0069] Figure 1 is a schematic diagram showing an example of an image forming apparatus according to the present embodiment;

[0070] Figure 2 is a schematic diagram showing an example of a fixing device according to the present embodiment;

[0071] Figure 3 is a schematic plan view showing an example of a sliding member according to the present embodiment;

[0072] Figure 4 is a schematic plan view showing another example of a sliding member according to the present embodiment;

[0073] Figure 5 is a schematic cross-sectional view showing an example of a sliding member according to the present embodiment;

[0074] Figure 6 is a schematic plan view showing another example of a sliding member according to the present embodiment;

[0075] Figure 7 It is a schematic plan view showing another example of the sliding member according to the present embodiment;

[0076] Figure 8 It is a schematic plan view showing another example of the sliding member according to the present embodiment.

[0077] Symbol Explanation

[0078] 1Y, 1M, 1C, 1K - photoreceptor, 2Y, 2M, 2C, 2K - charging roller, 3Y, 3M, 3C, 3K - laser beam, 3 - exposure device, 4Y, 4M, 4C, 4K - developing device, 5Y, 5M, 5C, 5K - primary transfer roller, 6Y, 6M, 6C, 6K - photoreceptor cleaning device, 10Y, 10M, 10C, 10K - process cartridge, 20 - intermediate transfer belt, 20a - intermediate transfer body cleaning device, 22 - driving roller, 24 - supporting roller, 26 - secondary transfer roller, 28 - fixing device, 30 - heating roller, 40 - pressure belt, 50 - pressing pad, 52 - belt travel guide, 60 - sliding sheet, 62 - lubricant, 64 - lubricant supply member, 100 - image forming apparatus, P - recording medium. Detailed Embodiment

[0079] Hereinafter, an embodiment as an example of the present invention will be described. These descriptions and examples are illustrative of the embodiment and do not limit the scope of the invention.

[0080] Within the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value described as one numerical range may also be replaced with the upper limit value or the lower limit value of other stepwise described numerical ranges. Moreover, within the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may also be replaced with the value shown in the examples.

[0081] Each component may contain a plurality of corresponding substances.

[0082] When referring to the amount of each component, in the case where there are a plurality of corresponding substances in each component, unless otherwise specified, it means the total amount of these multiple substances.

[0083] When explaining the embodiment while referring to the attached Figure 1 drawings, components having substantially the same function may sometimes be given the same reference numerals in all the drawings, and repeated explanations may be omitted.

[0084] <Sliding Member>

[0085] In the sliding member according to the present embodiment, a plurality of first grooves are provided at intervals in the width direction of the first groove at the center in the width direction of the sliding surface.

[0086] The angle formed by the first groove and the sliding direction is 45° or more and 90° or less.

[0087] Moreover, when observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, the angle A formed by the wall surface of the first groove on the downstream side of the sliding direction in the first groove and the sliding direction is 21° or more and 45° or less.

[0088] In addition, the "direction perpendicular to the first groove" means the direction perpendicular to the length direction of the first groove.

[0089] The sliding member according to the present embodiment becomes a sliding member with low sliding resistance and excellent maintainability of low sliding resistance due to the above structure. The reason is presumed as follows.

[0090] Conventionally, in sliding members, there has been a technique of arranging a plurality of grooves along the width direction or obliquely at intervals in the width direction of the groove on the sliding surface. When grooves are provided, lubricant stays in the grooves, and thus the lubricant is stably supplied to the contact portion between the sliding surface of the sliding member and the surface to be slid, thereby reducing the sliding resistance.

[0091] However, in recent years, in addition to requiring further reduction of the sliding resistance, maintaining a low sliding resistance has also been required.

[0092] In contrast, in the sliding member according to the present embodiment, when observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, the angle A formed by the wall surface of the first groove on the downstream side of the sliding direction in the plurality of first grooves is set to be 21° or more and 45° or less.

[0093] By setting the angle A within the above range, an increase in the friction coefficient with the surface to be slid caused by the provision of the grooves is suppressed, and the lubricant staying in the grooves is further stably supplied to the contact portion between the sliding surface of the sliding member and the surface to be slid.

[0094] Based on the above, it is presumed that the sliding member according to the present embodiment becomes a sliding member with low sliding resistance and excellent maintainability of low sliding resistance.

[0095] Hereinafter, the details of the sliding member according to the present embodiment will be described.

[0096] (Groove)

[0097] In the sliding member according to the present embodiment, for example, at the center portion in the width direction of the sliding surface, as the first groove, a plurality of grooves along the width direction of the sliding member are provided at intervals in the sliding direction (refer to Figure 3 ).

[0098] The central portion in the width direction of the sliding surface means a region sandwiched by both end portions in the width direction of the sliding surface, where regions with a length of 18% of the width of the sliding surface from both edges in the width direction of the sliding member toward the center are defined as both end portions in the width direction of the sliding surface.

[0099] As long as a plurality of first grooves in the width direction of the sliding surface are provided in the central portion in the width direction of the sliding surface.

[0100] Specifically, a plurality of first grooves in the width direction of the sliding surface may be provided in the central portion and both end portions in the width direction of the sliding surface (refer to Figure 3 ), or may be provided only in the central portion in the width direction of the sliding surface (refer to Figure 4 ).

[0101] In addition, when a plurality of first grooves in the width direction of the sliding surface are provided only in the central portion in the width direction of the sliding surface, it is preferable to provide inclined grooves connected to the first grooves in the central portion in the width direction, for example, at both end portions in the width direction of the sliding surface (refer to Figure 4 ). The inclined grooves are preferably inclined in the width direction such that the connecting portion is on the upstream side in the sliding direction (refer to Figure 4 ). By providing the inclined grooves, lubricant is less likely to escape from the central portion in the width direction of the sliding surface to both end portions, improving the maintainability of low sliding resistance.

[0102] Here, Figure 3 and Figure 4 in, SS represents the sliding surface, TA represents the first groove, TC represents the inclined groove, C represents the central portion in the width direction of the sliding surface, E represents both end portions in the width direction of the sliding surface, and the arrow SD represents the sliding direction.

[0103] When observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first groove (the sliding direction in the manner of Figure 3 ) and in the thickness direction, the angle A formed by the wall surface of the first groove on the downstream side in the sliding direction among the plurality of first grooves and the sliding direction is 21° or more and 45° or less. The angle A is preferably, for example, 23° or more and 40° or less, and more preferably 25° or more and 30° or less.

[0104] If the angle A is less than 21°, the lubricant retained in the first groove is difficult to supply to the contact portion between the sliding surface and the surface to be slid, resulting in an increase in sliding resistance.

[0105] If the angle A exceeds 45°, the friction coefficient with the surface to be slid increases, resulting in an increase in sliding resistance.

[0106] When observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, the angle B formed by the wall surface of the first groove on the upstream side in the sliding direction among the plurality of first grooves and the sliding direction is preferably, for example, 10° or more and 35° or less, more preferably 15° or more and 30° or less, and still more preferably 12° or more and 25° or less.

[0107] If the angle B is 35° or less, the lubricant remaining in the first groove is easily supplied to the contact portion between the sliding surface and the surface to be slid, the sliding resistance is reduced, and the maintainability of the low sliding resistance is also improved.

[0108] If the angle B is 10° or more, the friction coefficient with the surface to be slid is difficult to increase, the sliding resistance is reduced, and the maintainability of the low sliding resistance is also improved.

[0109] From the viewpoint of improving the low sliding resistance and the maintainability of the low sliding resistance, the absolute value of the difference between the angle A and the angle B is preferably, for example, 5° or more and 30° or less, more preferably 7° or more and 25° or less, and still more preferably 10° or more and 20° or less.

[0110] When observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, from the viewpoint of improving the low sliding resistance and the maintainability of the low sliding resistance, the depth of the first groove is preferably, for example, 15 μm or more and 45 μm or less, more preferably 20 μm or more and 40 μm or less, and still more preferably 25 μm or more and 38 μm or less.

[0111] When observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, from the viewpoint of improving the low sliding resistance and the maintainability of the low sliding resistance, the width of the first groove is preferably, for example, 70 μm or more and 190 μm or less, more preferably 85 μm or more and 180 μm or less, and still more preferably 100 μm or more and 170 μm or less.

[0112] When observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction, from the viewpoint of improving the low sliding resistance and the maintainability of the low sliding resistance, the pitch of the first grooves (that is, the interval between the first grooves) is preferably, for example, 200 μm or more and 900 μm or less, more preferably 300 μm or more and 700 μm or less, and still more preferably 400 μm or more and 500 μm or less.

[0113] Here, the angle A, the angle B, the depth of the first groove, the width of the first groove, and the pitch of the first grooves when observing the cut surface obtained by cutting the sliding member in the direction perpendicular to the first groove and in the thickness direction are defined as follows (refer to Figure 5 ).

[0114] The angle A refers to the angle (specifically, an acute angle) formed by the tangent line that contacts the wall surface of the first groove on the downstream side of the sliding direction at the position of 1 / 3 of the depth of the first groove and the sliding direction.

[0115] The angle B refers to the angle (specifically, an acute angle) formed by the tangent line that contacts the wall surface of the first groove on the upstream side of the sliding direction at the position of 1 / 3 of the depth of the first groove and the sliding direction.

[0116] The depth of the first groove refers to the length from the reference line corresponding to the sliding surface between adjacent first grooves to the bottom point of the deepest first groove. Additionally, the reference line is set as the line that becomes the arithmetic mean obtained by measuring 10 points of the thickness of the sliding member at the center of the sliding surface between adjacent first grooves.

[0117] The width of the first groove refers to the length between the edges of the groove that intersect with the reference line corresponding to the sliding surface between adjacent first grooves.

[0118] The pitch of the first groove refers to the length between the bottom points of the deepest first grooves among adjacent first grooves.

[0119] Moreover, the angle A, the angle B, the depth of the first groove, the width of the first groove, and the pitch of the first groove are respectively set as the arithmetic means obtained by measuring 10 points.

[0120] Here, Figure 5 the symbols in

[0121] SS: Sliding surface

[0122] TA: First groove

[0123] A: Angle A

[0124] B: Angle B

[0125] D: Depth of the first groove

[0126] W: Width of the first groove

[0127] P: Pitch of the first groove

[0128] SD: Sliding direction

[0129] T1: Wall surface of the first groove on the downstream side of the sliding direction at the position of 1 / 3 of the depth of the first groove

[0130] R1: Tangent line that contacts the wall surface of the first groove on the downstream side of the sliding direction at the position of 1 / 3 of the depth of the first groove

[0131] T2: Wall surface of the first groove on the upstream side of the sliding direction at the position of 1 / 3 of the depth of the first groove

[0132] R2: The tangent line that contacts the wall surface of the first groove on the upstream side in the sliding direction at a position one-third of the depth of the first groove

[0133] R3: The center of the sliding surface between adjacent first grooves

[0134] R: The reference line corresponding to the sliding surface between adjacent first grooves

[0135] Here, in the sliding member according to the present embodiment, the form of the first groove is not limited to the above form.

[0136] The first groove may be inclined in the sliding direction (refer to Figure 6 ). Specifically, the angle formed by the first groove and the sliding direction may be 45° or more and 90° or less.

[0137] In addition, the "angle formed by the first groove and the sliding direction" refers to the acute angle formed by the length direction of the first groove and the sliding direction.

[0138] Figure 6 The symbols in Figure 3 represent the following matters. Among them, the symbols other than these are the same as the symbols shown in

[0139] D1: The length direction of the first groove

[0140] θ1: The angle formed by the first groove and the sliding direction

[0141] In the sliding member according to the present embodiment, in addition to the first groove, a plurality of second grooves intersecting with the first groove may also be provided at intervals in the width direction of the sliding surface at the center in the width direction of the sliding surface (refer to Figures 7 - 8 ).

[0142] Wear powder is generated by the sliding of the sliding member against each other and is likely to deposit in the first groove. In contrast, by providing the second groove, the wear powder is easily discharged from the first groove. Therefore, the maintainability of low sliding resistance is improved.

[0143] The second groove is preferably, for example, within the same preferred range as the first groove in terms of the depth of the first groove, the width of the first groove, and the pitch of the first groove.

[0144] The angle formed by the first groove and the second groove ( Figure 7 and Figure 8 , refer to θ2) is preferably 45° or more and 90° or less, for example.

[0145] The so-called "angle formed by the first groove and the second groove" means the acute angle formed by the length direction of the first groove and the length direction of the second groove.

[0146] Here, Figure 7The groove pattern shown indicates a pattern in which a first groove is continuously provided along a direction perpendicular to the sliding direction and a second groove is continuously provided along the sliding direction.

[0147] In Figure 7 the groove pattern shown, it is easy to discharge the wear powder generated by the sliding of solids against each other. Therefore, the maintainability of low sliding resistance is improved.

[0148] In Figure 7 the groove pattern shown, the angle formed by the first groove and the sliding direction is 90°, and the angle formed by the first groove and the second groove is 90°.

[0149] Figure 8 The groove pattern shown indicates a pattern in which a first groove is continuously provided along a direction perpendicular to the sliding direction and a second groove is intermittently provided along the sliding direction.

[0150] In Figure 8 the groove pattern shown, the lubricant is easily supplied from the first groove to the contact portion between the sliding surface and the surface to be slid, and a discharge path for the wear powder is also ensured. Therefore, it is easy to improve the low sliding resistance and the maintainability of the low sliding resistance.

[0151] In Figure 8 the groove pattern shown, the second groove adjacent to the first groove as a boundary is provided in a stepped manner in the groove width direction. Specifically, the second groove provided between adjacent first grooves is arranged in a ladder shape. That is, the first groove and the second groove are provided in such a way that the sliding surface areas surrounded by the first groove and the second groove are arranged in a staggered manner.

[0152] In Figure 8 the groove pattern shown, the angle formed by the first groove and the sliding direction is 90°, and the angle formed by the first groove and the second groove is 90°.

[0153] And, the pitch of the second groove on one side with the first groove as a boundary ( Figure 8 in, refer to P1) and the pitch of the second groove on the other side with the first groove as a boundary ( Figure 8 in, refer to P2) are preferably in the same range as the pitch of the above-mentioned first groove, for example.

[0154] The stepped difference length of the second groove adjacent to the first groove as a boundary ( Figure 7 and Figure 8 in, refer to P3) is preferably 0.1 mm or more and 0.4 mm or less, more preferably 0.2 mm or more and 0.25 mm or less, for example.

[0155] Figures 7 - 8 The symbols in Figure 3 represent the following matters. Among them, the symbols other than these are the same as the symbols

[0156] D1: The longitudinal direction of the first groove

[0157] D2: The longitudinal direction of the second groove

[0158] θ1: The angle formed by the first groove and the sliding direction

[0159] θ2: The angle formed by the first groove and the second groove

[0160] P1: The pitch of the second groove on one side bounded by the first groove

[0161] P2: The pitch of the second groove on the other side bounded by the first groove

[0162] P3: The step difference length of the second groove adjacent to the first groove

[0163] TB: The second groove

[0164] The cross-sectional area of the first groove preferably gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction, for example.

[0165] The cross-sectional area of the second groove preferably gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction, for example.

[0166] The cross-sectional area of at least one of the first groove and the second groove decreases, whereby lubricant easily enters the sliding surface. Therefore, it is easy to improve low sliding resistance and the maintainability of low sliding resistance.

[0167] Here, the "cross-sectional area of the groove" is the cross-sectional area when the sliding member is cut in a direction perpendicular to the longitudinal direction of the groove and in the thickness direction.

[0168] "The cross-sectional area of the groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction" means any one of the following (1) and (2).

[0169] (1) In one groove, the cross-sectional area of the groove on the downstream side in the sliding direction is smaller than the cross-sectional area of the groove on the upstream side in the sliding direction.

[0170] (2) In multiple grooves, the cross-sectional area of the grooves located on the downstream side in the sliding direction is smaller than the cross-sectional area of the grooves located on the upstream side in the sliding direction.

[0171] Specifically, for example, it is preferable that the cross-sectional area B of the groove at the downstream side end portion on the sliding surface in contact with the sliding surface is smaller than the cross-sectional area A of the groove at the upstream side end portion.

[0172] The ratio (A / B) of the cross-sectional area A of the groove to the cross-sectional area B of the groove is preferably 1 or more and 9 or less, and more preferably 2 or more and 4 or less, for example.

[0173] When adjusting the cross-sectional area of each groove, for example, it is preferable to adjust the depth of the groove.

[0174] Specifically, the cross-sectional area of each groove in the upstream end portion in the sliding direction is preferably, for example, 700 μm 2 or more and 4300 μm 2 or less. The depth of each groove in the upstream end portion in the sliding direction is preferably, for example, 20 μm or more and 45 μm or less.

[0175] The cross-sectional area of each groove in the downstream end portion in the sliding direction is preferably, for example, 175 μm 2 or more and 1430 μm 2 or less. The depth of each groove in the downstream end portion in the sliding direction is preferably, for example, 5 μm or more and 45 μm or less.

[0176] In addition, when the groove is not located at the upstream end portion or the downstream end portion in the sliding direction, the cross-sectional area and the depth of each groove are set to the cross-sectional area and the depth of the groove closest to the upstream end portion or the downstream end portion in the sliding direction.

[0177] As a method of providing the groove on the sliding surface, a known method such as stamping is adopted.

[0178] Next, the structure of the sliding member according to the present embodiment will be described in detail.

[0179] The sliding sheet according to the present embodiment preferably includes, for example, a heat-resistant thermoplastic resin on the sliding surface.

[0180] Specifically, the sliding sheet according to the present embodiment is composed of a single layer of a resin base material layer containing a heat-resistant thermoplastic resin.

[0181] However, the sliding sheet may also be a laminate of a resin base material layer and another layer provided on the side opposite to the sliding surface of the resin base material layer.

[0182] Examples of the heat-resistant thermoplastic resin include polyimide resin, polyether ether ketone resin, polyphenylene sulfide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polysulfone resin, polyamide resin, fluororesin, etc.

[0183] Among these, as the heat-resistant thermoplastic resin, for example, at least one resin selected from the group consisting of polyether ether ketone resin, polyphenylene sulfide resin, polyetherimide resin, and polysulfone resin is preferably selected, and at least one resin selected from the group consisting of polyether ether ketone resin and polyphenylene sulfide resin is more preferably selected.

[0184] These resins (in particular, polyether ether ketone resin and polyphenylene sulfide resin) are preferably used because they have, for example, high wear resistance, high toughness, and high elastic modulus.

[0185] For the purpose of reducing the sliding resistance of the sliding surface, known additives such as carbon fiber, carbon nanotube, resin particles having a siloxanyl group (particles such as thermosetting silicone resin particles, silicone oil gum, silicone elastomer, siloxane-modified polyetherimide, etc.) can be included in the resin base material layer constituting the sliding surface.

[0186] In the resin base material layer constituting the sliding surface, in addition to this, components such as a conductive agent, a filler for improving mechanical strength, an antioxidant for preventing thermal deterioration, a surfactant, a heat-resistant anti-aging agent, etc. can also be included.

[0187] <Fixing device / Image forming device>

[0188] The fixing device according to the present embodiment includes: a first rotating body; a second rotating body disposed in contact with the first rotating body; a pressing member disposed on the inner peripheral surface of the second rotating body and pressing the second rotating body against the first rotating body from the inner peripheral surface of the second rotating body; a sliding member interposed between the inner peripheral surface of the second rotating body and the pressing member; and a lubricant interposed between the inner peripheral surface of the second rotating body and the sliding member.

[0189] Moreover, in the fixing device according to the present embodiment, as the sliding member, the sliding member according to the present embodiment described above is applied.

[0190] The image forming device according to the present embodiment includes:

[0191] An image holding body;

[0192] A latent image forming device that forms a latent image on the surface of the image holding body;

[0193] A developing device that develops the latent image into a toner image using a developer;

[0194] A transfer device that transfers the developed toner image onto a recording medium; and

[0195] A fixing device that fixes the toner image on the recording medium.

[0196] Moreover, in the image forming device according to the present embodiment, as the fixing device, the fixing device according to the present embodiment described above is applied.

[0197] Hereinafter, an example of the fixing device and the image forming device according to the present embodiment will be described while referring to the attached Figure 1 An example of the fixing device and the image forming device according to the present embodiment will be described.

[0198] Figure 1 It is a schematic diagram showing an example of the image forming device according to the present embodiment. Figure 2 It is a schematic diagram showing an example of the fixing device according to the present embodiment.

[0199] (Structure of the image forming apparatus)

[0200] As shown Figure 1 in the figure, the image forming apparatus 100 according to the present embodiment includes electrophotographic first to fourth process cartridges 10Y, 10M, 10C, and 10K (an example of an image forming unit) that output images of respective colors of yellow (Y), magenta (M), cyan (C), and black (K) based on color-separated image data. These process cartridges 10Y, 10M, 10C, and 10K are arranged side by side separately from each other along the outer peripheral surface of the intermediate transfer belt 20. In addition, these process cartridges 10Y, 10M, 10C, and 10K can be attached to and detached from the image forming apparatus main body.

[0201] The intermediate transfer belt 20 as an intermediate transfer body is disposed above the respective process cartridges 10Y, 10M, 10C, and 10K so that its outer peripheral surface faces the respective process cartridges ( Figure 1 in the middle). The intermediate transfer belt 20 is wound around the driving roller 22 and the support roller 24 that are separately arranged and in contact with the inner peripheral surface of the intermediate transfer belt 20, and is disposed while being given tension so as to travel annularly in the direction from the first process cartridge 10Y toward the fourth process cartridge 10K.

[0202] In addition, the support roller 24 is pressed by an elastic member such as a spring (not shown) in a direction away from the driving roller 22, thereby applying tension to the intermediate transfer belt 20 wound between the two. And, on the outer peripheral surface of the intermediate transfer belt 20, an intermediate transfer body cleaning device 20a is provided so as to face the driving roller 22.

[0203] The first to fourth process cartridges 10Y, 10M, 10C, and 10K have substantially the same structure. Therefore, the first process cartridge 10Y that forms a yellow image and is disposed on the upstream side in the traveling direction of the intermediate transfer belt will be described as a representative. In addition, the description of the second to fourth process cartridges 10M, 10C, and 10K is omitted by attaching the same reference numerals with magenta (M), cyan (C), and black (K) instead of yellow (Y) to the same parts as those of the first process cartridge 10Y.

[0204] The first process cartridge 10Y has a photoreceptor 1Y that functions as an image holding body. Around the photoreceptor 1Y, a charging roller (an example of a charging device) 2Y that charges the surface of the photoreceptor 1Y to a predetermined potential, a developing device 4Y that supplies the charged toner contained in the developer to the electrostatic latent image and develops the electrostatic latent image, and a photoreceptor cleaning device 6Y that removes the toner remaining on the surface of the photoreceptor 1Y after primary transfer are sequentially arranged. These are integrally formed in a housing 11Y (frame). Similarly, for the second to fourth process cartridges 10M, 10C, and 10K, each component is integrally formed in housings 11M, 11C, and 11K (frames).

[0205] Further, together with the first processing cartridge 10Y, there are provided a primary transfer roller 5Y (an example of a primary transfer device) that transfers the developed toner image onto the intermediate transfer belt 20, and an exposure device 3 that forms an electrostatic latent image by exposing the charged surface with a laser beam 3Y based on the color-separated image signal, thereby constituting an image forming unit.

[0206] In addition, the charging roller 2Y and the exposure device 3 are examples of a latent image forming device.

[0207] In addition, the primary transfer roller 5Y is disposed inside the intermediate transfer belt 20 and is provided at a position facing the photoreceptor 1Y. Further, a bias power source (not shown) for applying a primary transfer bias is connected to each of the primary transfer rollers 5Y, 5M, 5C, and 5K. Each bias power source can change the transfer bias applied to each primary transfer roller through control by a control unit (not shown).

[0208] (Structure of Fixing Device)

[0209] As Figure 2 shown, the fixing device 28 includes a heating roller 30 (an example of a first rotating body) and a pressure belt 40 (an example of a second rotating body), and the heating roller 30 and the pressure belt 40 are disposed opposite to each other. The pressure belt 40 is pressed against the heating roller 30 by a pressing pad 50 (an example of a pressing member) disposed inside its circumference, and is crimped to form a contact portion, and is guided along a belt travel guide 52 and is driven to follow by receiving a driving force from the heating roller 30.

[0210] A sliding sheet 60 (an example of a sliding member) is interposed between the pressure belt 40 and the pressing pad 50. And a lubricant 62 (an example of a lubricant) is interposed between the sliding sheet 60 and the inner circumferential surface of the pressure belt 40. In addition, the lubricant 62 is supplied to the inner circumferential surface of the pressure belt 40, for example, by a lubricant supply member 64 provided on a part of the belt travel guide 52, and is interposed between the sliding sheet 60 and the inner circumferential surface of the pressure belt 40.

[0211] Here, Figure 2 in, T represents the toner image.

[0212] - Heating Roller 30 (An Example of a First Rotating Body)-

[0213] The heating roller 30 is constituted by sequentially forming an elastic layer 30b and an anti-sticking layer 30c on a metal hollow core 30a having a heating source 31 such as a halogen lamp inside, for example.

[0214] The metal core 30a is formed of a cylindrical body made of a metal such as aluminum or stainless steel, for example. The elastomer layer 30b is formed of, for example, HTV silicone rubber or fluororubber (with a rubber hardness of around 45 degrees on the JIS-A scale, and the rubber hardness is measured using a spring-type A durometer manufactured by Teclock Corporation and complying with JIS K6301 with an additional load of 1,000 gf) with a thickness of 2 mm or more and around 5 mm or less. The anti-stick layer 30c is formed of, for example, fluororubber, silicone rubber, fluororesin, etc. with a thickness of 20 μm or more and 50 μm or less. Of course, it is not limited to these, and it can also be formed of conventionally known materials.

[0215] Regarding the heating roller 30, the fixing roller is adjusted in speed by a drive source (not shown), and is rotationally driven, for example, at a circumferential speed of 260 mm / sec. The outer diameter of the heating roller 30 is generally, for example, 25 mm or more and around 80 mm or less.

[0216] The surface temperature of the heating roller 30 is detected by a temperature sensor (not shown) in contact with the surface, and is controlled by a control circuit (not shown) so that the surface temperature becomes, for example, 175°C.

[0217] - Pressure belt 40 (an example of the second rotating body)-

[0218] The inner circumferential surface of the pressure belt 40 is formed, for example, by including polyimide resin, polyamideimide resin, polyetheretherketone resin, polyphenylene sulfide resin, polyethersulfone resin, polysulfone resin, polyphenylsulfone resin, etc.

[0219] In the resin base material layer, other components may be included in addition to the resin. As other components, for example, a conductive agent, a filler for improving mechanical strength, an antioxidant for preventing thermal deterioration, a surfactant, a heat-resistant anti-aging agent, etc. can be cited.

[0220] Here, an example where the first rotating body is a heating roller and the second rotating body is a pressure belt is given, but it also includes a mode where the first rotating body is a pressure roller and the second rotating body is a heating belt.

[0221] When the first rotating body is a pressure roller, the structure of the pressure roller is preferably the same as the structure of the above-mentioned heating roller 30, for example.

[0222] When the second rotating body is a heating belt, the structure of the heating belt is preferably the same as the structure of the above-mentioned pressure belt 40, for example.

[0223] In particular, when the second rotating body is a heating belt, it can be a single-layer body of a resin base material layer constituting the inner peripheral surface of the heating belt, or a laminate having a resin base material layer constituting the inner peripheral surface of the heating belt, an elastic layer provided on the resin base material layer, and an anti-sticking layer provided on the elastic layer, or a laminate having a resin base material layer constituting the inner peripheral surface of the heating belt and an anti-sticking layer provided on the resin base material layer, or a laminate formed by providing a metal layer on the resin base material layer constituting the inner peripheral surface of the heating belt, providing an elastic layer on the metal layer, and providing an anti-sticking layer on the elastic layer.

[0224] The elastic layer will be described.

[0225] The elastic layer is composed of a heat-resistant elastic material.

[0226] Examples of the heat-resistant elastic material include silicone rubber and fluororubber.

[0227] Examples of the silicone rubber include RTV (Room Temperature Vulcanizing) silicone rubber, HTV (High Temperature Vulcanizing) silicone rubber, liquid silicone rubber, etc. Specifically, polydimethylsilicone rubber, methyl vinyl silicone rubber, methyl phenyl silicone rubber, fluorosilicone rubber, etc. can be cited.

[0228] Examples of the fluororubber include vinylidene fluoride-based rubber, tetrafluoroethylene / propylene-based rubber, tetrafluoroethylene / perfluoromethyl vinyl ether rubber, phosphazene-based rubber, fluoropolyether, etc.

[0229] The elastic layer may also contain other components. Examples of the other components include filler materials, conductive agents, softening agents (such as paraffins), processing aids (such as stearic acid), anti-aging agents (such as amines), vulcanizing agents (such as sulfur, metal oxides, peroxides), functional filler materials (such as alumina), etc.

[0230] The anti-sticking layer will be described.

[0231] The anti-sticking layer contains, for example, a heat-resistant anti-sticking material.

[0232] Examples of the heat-resistant anti-sticking material include fluororubber, fluororesin, silicone resin, polyimide resin, etc.

[0233] Among these, as the heat-resistant anti-sticking material, for example, fluororesin is preferably used. As the fluororesin, specifically, for example, polytetrafluoroethylene (PTFE) can be cited; tetrafluoroethylene-perfluoromethyl vinyl ether copolymer (MFA), tetrafluoroethylene-perfluoroethyl vinyl ether copolymer (EFA), tetrafluoroethylene-perfluoropropyl vinyl ether copolymer and other tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers (PFA), etc. Moreover, tetrafluoroethylene-hexafluoropropylene copolymer (FEP), ethylene-tetrafluoroethylene copolymer (ETFE), polyvinylidene fluoride (PVDF), polychlorotrifluoroethylene (PCTFE), polyvinyl fluoride (PVF), etc. can be cited.

[0234] Among these, especially from the aspects of heat resistance, mechanical properties, etc., polytetrafluoroethylene (PTFE) and tetrafluoroethylene-perfluoromethyl vinyl ether copolymer (MFA), tetrafluoroethylene-perfluoroethyl vinyl ether copolymer (EFA) and other tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers (PFA) are used.

[0235] The thickness of the anti-sticking layer is preferably set to 5 μm to 100 μm, more preferably set to 10 μm to 30 μm, for example.

[0236] -Pressing pad 50 (an example of a pressing member)-

[0237] The pressing pad 50 has two pressing portions 51a and 51b with different hardnesses along the running direction of the recording medium P. The pressing portion 51a on the side where the recording medium P protrudes in the pressing pad 50 is composed of a rubber-like elastic member, and the pressing portion 51b on the side where the recording medium P is discharged is composed of a hard pressure-applying member such as metal, so that the pressure in the contact area is higher on the side where the recording medium P is discharged than on the side where the recording medium P protrudes. The pressing portions 51a and 51b are supported by a bracket 51c and press the heating roller 30 from the inner peripheral surface of the pressing belt 40 via a sliding sheet 60 (an example of a sliding member).

[0238] -Sliding sheet 60 (an example of a sliding member)-

[0239] The sliding member according to the present embodiment is applicable to the sliding sheet 60.

[0240] -Lubricant 62 (an example of a lubricant)-

[0241] As the lubricant 62, for example, fluorine oil, silicone oil, synthetic lubricating grease formed by mixing a solid substance and a liquid, etc. can be cited.

[0242] As the fluorine oil, for example, perfluoropolyether oil, modified perfluoropolyether oil, etc. can be cited.

[0243] As the silicone oil, for example, dimethyl silicone oil, dimethyl silicone oil added with an organometallic salt, dimethyl silicone oil added with a hindered amine, dimethyl silicone oil added with an organometallic salt and a hindered amine, methylphenyl silicone oil, amino-modified silicone oil, amino-modified silicone oil added with an organometallic salt, amino-modified silicone oil added with a hindered amine, carboxyl-modified silicone oil, silanol-modified silicone oil, sulfonic acid-modified silicone oil, etc. can be cited.

[0244] As the synthetic lubricating grease, for example, silicone grease (i.e., grease containing the above silicone oil), fluorine grease (i.e., grease containing the above fluorine oil), etc. can be cited.

[0245] In addition to the oil, the lubricant 62 may contain other components. As the other components, grease (such as silicone grease), heat conductor, antioxidant, surfactant, silicone particles, organometallic salt, hindered amine, etc. can be cited.

[0246] (Image forming operation of the image forming apparatus)

[0247] Hereinafter, the image forming operation of the image forming apparatus according to the present embodiment will be described. In addition, the image forming operation will be described by taking the operation of forming a yellow image in the first processing cartridge 10Y as a representative.

[0248] First, before the image forming operation, the surface of the photoreceptor 1Y is charged to a potential of, for example, -600 V or more and -800 V or less by the charging roller 2Y.

[0249] The photoreceptor 1Y is formed by laminating a photosensitive layer on a conductive substrate, for example. This photosensitive layer is usually a high resistance, but has the property that the resistivity of the portion irradiated with the laser beam changes when irradiated with the laser beam 3Y. Therefore, according to the yellow image data sent from a control unit (not shown), the laser beam 3Y is output to the surface of the charged photoreceptor 1Y via the exposure device 3. The laser beam 3Y irradiates the photosensitive layer on the surface of the photoreceptor 1Y, whereby an electrostatic latent image of the yellow print pattern is formed on the surface of the photoreceptor 1Y.

[0250] The electrostatic latent image thus formed on the photoreceptor 1Y rotates to the development position as the photoreceptor 1Y advances. Then, at this development position, the electrostatic latent image on the photoreceptor 1Y is visualized (toner image) by the developing device 4Y.

[0251] In the developing device 4Y, for example, a developer containing yellow toner and carrier is accommodated. The yellow toner is triboelectrically charged by agitation inside the developing device 4Y and has a charge with the same polarity (negative polarity) as the charge carried on the photoreceptor 1Y. By passing the surface of the photoreceptor 1Y through the developing device 4Y, the yellow toner electrostatically adheres only to the discharged latent image portions on the surface of the photoreceptor 1Y, and thus the latent image is developed with the yellow toner. The photoreceptor 1Y on which a yellow toner image is formed continues to travel, and thus the toner image developed on the photoreceptor 1Y is transferred to the primary transfer position.

[0252] If the yellow toner image on the photoreceptor 1Y is transferred to the primary transfer position, a primary transfer bias is applied to the primary transfer roller 5Y, and an electrostatic force from the photoreceptor 1Y toward the primary transfer roller 5Y acts on the toner image, transferring the toner image on the photoreceptor 1Y to the intermediate transfer belt 20. The transfer bias applied at this time is of the opposite polarity (+) to the polarity (-) of the toner, and for example, in the first process cartridge 10Y, it is controlled by a control unit (not shown) with a constant current of about +10 μA.

[0253] Also, the primary transfer bias applied to the primary transfer rollers 5M, 5C, 5K after the second process cartridge 10M is controlled in the same manner.

[0254] In this way, the intermediate transfer belt 20 on which the yellow toner image is transferred by the first process cartridge 10Y is sequentially conveyed through the second to fourth process cartridges 10M, 10C, 10K, and the toner images of each color are superposed in the same manner to perform multiple transfers.

[0255] The intermediate transfer belt 20 on which the toner images of all colors are transferred multiple times through the first to fourth process cartridges reaches the secondary transfer portion constituted by the intermediate transfer belt 20, a support roller 24 in contact with the inner peripheral surface of the intermediate transfer belt 20, and a secondary transfer roller (an example of a secondary transfer device) 26 disposed on the image holding surface side of the intermediate transfer belt 20. On the other hand, the recording medium P is supplied to between the secondary transfer roller 26 and the intermediate transfer belt 20 via a supply mechanism, and a secondary transfer bias is applied to the support roller 24. The transfer bias applied at this time is of the same polarity (-) as the polarity (-) of the toner, and an electrostatic force from the intermediate transfer belt 20 toward the recording medium P acts on the toner image, transferring the toner image on the intermediate transfer belt 20 to the recording medium P. In addition, the secondary transfer bias at this time is determined based on the resistance detected by a resistance detection member (not shown) that detects the resistance of the secondary transfer portion and is controlled with a constant voltage.

[0256] In addition, the intermediate transfer belt 20, the primary transfer roller 5Y, and the secondary transfer roller 26 are examples of a transfer device.

[0257] Thereafter, the recording medium P is fed into the fixing device 28 and inserted through the contact area formed by the pressure contact between the heating roller 30 that is rotationally driven in the arrow direction and the pressure belt 40. At this time, the recording medium P is inserted through such that the surface of the recording medium P on which the unfixed toner image is formed faces the surface of the heating roller 30. When the recording medium P passes through this contact area, heat and pressure are applied to the recording medium P, whereby the unfixed toner image is fixed on the recording medium P. After the fixed recording medium P passes through the contact area, it is peeled off from the heating roller 30 and discharged from the fixing device 28.

[0258] The fixing process is thus performed to be permanently fixed on the recording medium P. The recording medium P on which the fixing of the color image is completed is conveyed to the discharging unit, thereby ending a series of color image forming operations.

[0259] Examples

[0260] Hereinafter, examples will be described, but the present invention is not limited by any of these examples. In addition, in the following description, "parts" and "%" are based on mass unless otherwise specified.

[0261] <Examples 1 to 22, Comparative Examples 1 to 3>

[0262] The polyetheretherketone (PEEK) resin (Victrex 450G (manufactured by Victrex)) was melted by heating with a twin-screw extrusion melt kneader (twin-screw melt kneading extruder L / D60 (manufactured by PARKER CORPORATION)) at 380°C. In 100 parts by mass of the melted PEEK resin, 10 parts by mass of unfixed heat-curing silicone resin particles ("KMP590" manufactured by Shin-Etsu Chemical Co., Ltd., average particle diameter = 2 μm) were supplied from the side of the kneader using a side feeder and melt kneaded. The kneaded melt was put into a water bath for cooling and solidification, and cut into a target size to obtain mixed resin particles containing silicone resin particles.

[0263] The obtained mixed resin particles were put into a single-screw extrusion device, and the melted mixed resin was extruded in a sheet shape from a T-die heated to 380°C (melt extrusion gap 200 μm), and wound around a cooling roller at 190°C for cooling. The shape of the surface of the mold roller was imparted to the cooled sheet between the mold roller heated to 250°C and the heat-resistant silicone rubber roller at a pressure of 40 Mpa, and a sheet having a plurality of grooves in the width direction formed at intervals in the sheet length direction at the center and both ends of the sheet width direction was obtained. And the embossed sheet was cut into a specified size.

[0264] Thus, a sliding sheet was obtained in which a plurality of grooves in the width direction were provided at intervals in the sliding direction in the central portion and both end portions in the width direction of the sliding surface, and the surface was set as the sliding surface.

[0265] In addition, regarding the shape of the groove, when observing the cut surface obtained by cutting the sliding sheet along the sliding direction and the thickness direction, it was V-shaped and had the dimensions shown in Table 1.

[0266] Moreover, the shape of the groove was changed according to the surface shape of the mold roll, and sliding sheets of each example were obtained.

[0267] <Comparative Example 3: Sliding Sheet Impregnated with Fluororesin in Glass Cloth>

[0268] A glass cloth sheet impregnated with a fluororesin (product name: FGF400) manufactured by Chukoh Chemical Industries, Ltd., which was obtained by infiltrating a PTFE resin dispersion into a glass cloth, drying it at 150 °C, heating and firing it at 380 °C, and then cooling it, was used as the sliding sheet.

[0269] In addition, the notations in Table 1 represent the following matters.

[0270] Angle A: The angle formed by the wall surface of the groove on the downstream side in the sliding direction in the first groove and the sliding direction when observing the cut surface obtained by cutting the sliding sheet along the sliding direction and the thickness direction

[0271] Angle B: The angle formed by the wall surface of the groove on the upstream side in the sliding direction in the first groove and the sliding direction when observing the cut surface obtained by cutting the sliding sheet along the sliding direction and the thickness direction

[0272] Here, in Examples 20 to 22, the first groove and the second groove were provided as follows.

[0273] · The first groove was provided such that the width and cross-sectional area of the first groove at the downstream end and the upstream end in the sliding direction became the values shown in Table 1, and gradually decreased from the upstream side in the sliding direction toward the downstream side in the sliding direction.

[0274] · The second groove was provided such that the width and cross-sectional area of one second groove at the downstream end and the upstream end in the sliding direction became the values shown in Table 1, and gradually decreased from the upstream side in the sliding direction toward the downstream side in the sliding direction.

[0275] In Examples 20 to 21, the pitch of the second groove shown in Table 1 corresponded to the pitch of the second groove on one side with the first groove as the boundary ( Figure 8 refer to "P1" in Figure 8In reference to “P2”), the step difference length of the adjacent second slot with the first slot as the boundary is set to a size that is 1 / 2 of the pitch of the first slot shown in Table 1.

[0276] <Evaluation>

[0277] The sliding sheet of each example was installed in the fixing device of the image forming apparatus “Revoria Press EC1100” manufactured by FUJIFILM Business Innovation Corp.

[0278] The following evaluation was carried out using this image forming apparatus.

[0279] (Initial sliding resistance)

[0280] The coefficient of friction between the sliding sheet and the sliding part of the fixing member in the image forming apparatus was measured as follows. This measurement was carried out before passing the paper through the fixing device (i.e., before image formation).

[0281] The current value of the motor that drives the heating roller, which is the driving roller of the fixing device, was measured. A calibration curve showing the relationship between the motor current value and the coefficient of friction was previously drawn, and based on the calibration curve, the coefficient of friction was calculated from the current value.

[0282] Moreover, the target coefficient of friction was set to 0.08, and the evaluation was carried out according to the following evaluation criteria.

[0283] A++: The coefficient of friction is less than 60% of the target coefficient of friction

[0284] A+: The coefficient of friction is less than 70% of the target coefficient of friction

[0285] A: The coefficient of friction is less than 80% of the target coefficient of friction

[0286] B+: The coefficient of friction is 80% or more and 90% or less of the target coefficient of friction

[0287] B: The coefficient of friction is 90% or more and 100% or less of the target coefficient of friction

[0288] C: The coefficient of friction exceeds 100% and is 120% or less of the target coefficient of friction

[0289] D: The coefficient of friction exceeds 120% and is 140% or less of the target coefficient of friction

[0290] E: The coefficient of friction exceeds 140% of the target coefficient of friction

[0291] (Sliding resistance maintainability)

[0292] Image formation was performed by an image forming apparatus, and 1,200,000 sheets of paper passed through the fixing device. Thereafter, the coefficient of friction between the sliding sheet and the sliding portion of the fixing member in the image forming apparatus was measured in the same manner as the evaluation of the "initial sliding resistance". And the evaluation was performed according to the following evaluation criteria.

[0293] A++: The coefficient of friction is 40% or less of the above target coefficient of friction (=0.08)

[0294] A+: The coefficient of friction is 50% or less of the above target coefficient of friction (=0.08)

[0295] A: The coefficient of friction is 60% or less of the above target coefficient of friction (=0.08)

[0296] B+: The coefficient of friction exceeds 60% and is less than 70% of the above target coefficient of friction (=0.08)

[0297] B: The coefficient of friction exceeds 70% and is less than 80% of the above target coefficient of friction (=0.08)

[0298] C: The coefficient of friction is 80% or more and less than 100% of the above target coefficient of friction (=0.08)

[0299] D: The coefficient of friction is 100% or more and 120% or less of the above target coefficient of friction (=0.08)

[0300] E: The coefficient of friction exceeds 120% of the above target coefficient of friction (=0.08)

[0301]

[0302] From the above results, it can be seen that the sliding sheet of this embodiment has lower sliding resistance and excellent maintainability of low sliding resistance compared with the sliding sheet of the comparative example.

[0303] This embodiment includes the following modes. (1)

[0305] A sliding member, wherein

[0306] A plurality of first grooves are provided at intervals in the width direction of the sliding surface at the center of the width direction of the first groove,

[0307] The angle formed by the first groove and the sliding direction is 45° or more and 90° or less,

[0308] When observing the cut surface obtained by cutting the sliding member along the direction perpendicular to the first groove and in the thickness direction, the angle A formed by the wall surface of the first groove on the downstream side of the sliding direction in the first groove and the sliding direction is 21° or more and 45° or less. (2)

[0310] The sliding member according to (1), wherein

[0311] When observing a cut surface obtained by cutting the sliding member along a direction perpendicular to the first groove and in the thickness direction, the angle B formed by the wall surface of the first groove on the upstream side in the sliding direction in the first groove and the sliding direction is 10° or more and 35° or less. (3)

[0313] The sliding member according to (1) or (2), wherein

[0314] As the first groove, a plurality of grooves in the width direction of the sliding surface are provided at intervals in the sliding direction. (4)

[0316] The sliding member according to any one of (1) to (3), wherein

[0317] A plurality of second grooves are provided at intervals in the width direction of the second groove at the central portion in the width direction of the sliding surface, and the angle formed by the first groove and the second groove is 45° or more and 90° or less. (5)

[0319] The sliding member according to (4), wherein

[0320] The first groove is continuously provided along a direction orthogonal to the sliding direction, and the second groove is intermittently provided along the sliding direction. (6)

[0322] The sliding member according to any one of (1) to (5), wherein

[0323] The cross-sectional area of the first groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction. (7)

[0325] The sliding member according to (4), wherein

[0326] The cross-sectional area of the second groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction. (8)

[0328] The sliding member according to any one of (1) to (7), wherein

[0329] The angle A is 23° or more and 40° or less. (9)

[0331] The sliding member according to (2), wherein

[0332] The angle B is 15° or more and 30° or less. (10)

[0334] The sliding member according to (2), wherein

[0335] The absolute value of the difference between the angle A and the angle B is 5° or more and 30° or less. (11)

[0337] The sliding member according to (10), wherein

[0338] The absolute value of the difference between the angle A and the angle B is 7° or more and 25° or less. (12)

[0340] A fixing device, comprising:

[0341] A first rotating body;

[0342] A second rotating body disposed in contact with the first rotating body;

[0343] A pressing member disposed on the inner peripheral surface of the second rotating body and pressing the second rotating body from the inner peripheral surface of the second rotating body against the first rotating body;

[0344] The sliding member according to any one of (1) to (11), interposed between the inner peripheral surface of the second rotating body and the pressing member; and

[0345] A lubricant interposed between the inner peripheral surface of the second rotating body and the sliding member. (13)

[0347] An image forming apparatus, comprising:

[0348] An image holding body;

[0349] A latent image forming device that forms a latent image on the surface of the image holding body;

[0350] A developing device that develops the latent image into a toner image using a developer;

[0351] A transfer device that transfers the developed toner image onto a recording medium; and

[0352] The fixing device according to (12), which fixes the toner image on the recording medium.

[0353] The effects of the above method are as follows.

[0354] According to the invention according to (1) or (3), there is provided a sliding member as follows: It is provided at intervals in the width direction of the sliding surface in the width direction center part of the sliding surface with respect to a plurality of first grooves, the angle formed by the first grooves and the sliding direction is 45° or more and 90° or less, and when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first grooves and in the thickness direction, compared with a sliding member in which the angle A between the wall surface of the first groove on the downstream side in the sliding direction in the first groove and the sliding direction is less than 21° or exceeds 45°, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0355] According to the invention according to (2), there can be provided a sliding member as follows: Compared with the case where the angle B between the wall surface of the first groove on the upstream side in the sliding direction in the first groove and the sliding direction is less than 10° or exceeds 35° when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first grooves and in the thickness direction, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0356] According to the invention according to (4), there can be provided a sliding member as follows: Compared with the case where a plurality of second grooves having an angle of 45° or more and 90° or less with the first grooves are not provided at intervals in the width direction of the sliding surface in the width direction center part of the sliding surface, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0357] According to the invention according to (5), there can be provided a sliding member as follows: Compared with the case where the first grooves are not continuously provided in a direction perpendicular to the sliding direction or the second grooves are not intermittently provided in the sliding direction, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0358] According to the invention according to (6), there can be provided a sliding member as follows: Compared with the case where the cross-sectional area of the first grooves does not change from the upstream side in the sliding direction to the downstream side in the sliding direction, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0359] According to the invention according to (7), there can be provided a sliding member as follows: Compared with the case where the cross-sectional area of the second grooves does not change from the upstream side in the sliding direction to the downstream side in the sliding direction, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0360] According to the invention according to (8), there can be provided a sliding member as follows: Compared with the case where the angle A is less than 23° or exceeds 40°, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0361] According to the invention according to (9), there can be provided a sliding member as follows: Compared with the case where the angle B is less than 15° or exceeds 30°, it has low sliding resistance and excellent maintainability of low sliding resistance.

[0362] According to the invention related to (10), it is possible to provide a sliding member that has lower sliding resistance and excellent maintainability of the lower sliding resistance as compared with the case where the absolute value of the difference between angle A and angle B is less than 5° or more than 30°.

[0363] According to the invention related to (11), it is possible to provide a sliding member that has lower sliding resistance and excellent maintainability of the lower sliding resistance as compared with the case where the absolute value of the difference between angle A and angle B is less than 7° or more than 25°.

[0364] According to the invention related to (12) or (13), there is provided a fixing device including a sliding member having the following characteristics: a plurality of first grooves are provided at intervals in the width direction of a sliding surface at the center in the width direction, the angle formed by the first grooves and the sliding direction is 45° or more and 90° or less, and when observing a cut surface obtained by cutting the sliding member in a direction perpendicular to the first grooves and in the thickness direction, the sliding member has lower sliding resistance and excellent maintainability of the lower sliding resistance as compared with the case where the angle A formed by the wall surface of the first groove on the downstream side in the sliding direction among the plurality of first grooves and the sliding direction is less than 21° or more than 45°.

[0365] The above-described embodiments of the present invention are provided for the purpose of illustration and explanation. In addition, the embodiments of the present invention do not comprehensively and exhaustively cover the present invention and do not limit the present invention to the disclosed forms. Obviously, various modifications and variations are apparent to those skilled in the art to which the present invention pertains. This embodiment is selected and described in order to most easily explain the principle of the present invention and its applications. Thus, other technicians in the technical field can understand the present invention through various modified examples optimized for specific uses assumed for various embodiments. The scope of the present invention is defined by the above claims and their equivalents.

Claims

1. A sliding component, wherein: A plurality of first grooves are provided at intervals in the width direction of the first groove at a central portion of the sliding surface in the width direction. The angle between the first groove and the sliding direction is greater than 45° and less than 90°, When observing a cut surface obtained by cutting the sliding component along a direction perpendicular to the first groove and in a thickness direction, an angle A formed by a wall surface of the first groove on the downstream side of the sliding direction in the first groove and the sliding direction is greater than 21° and less than 45°.

2. The sliding component according to claim 1, wherein: When observing a cut surface obtained by cutting the sliding component along a direction perpendicular to the first groove and in a thickness direction, an angle B formed by a wall surface of the first groove on the upstream side of the sliding direction in the first groove and the sliding direction is greater than 10° and less than 35°.

3. The sliding component according to claim 1 or 2, wherein: As the first grooves, a plurality of grooves along the width direction of the sliding surface are provided at intervals in the sliding direction.

4. The sliding component according to any one of claims 1 to 3, wherein: A plurality of second grooves are provided at intervals in a width direction of the second groove at a width center portion of the sliding surface, and an angle formed by the first groove and the second groove is greater than or equal to 45° and less than or equal to 90°.

5. The sliding component according to claim 4, wherein: The first groove is continuously provided along a direction perpendicular to the sliding direction, and the second groove is intermittently provided along the sliding direction.

6. The sliding component according to any one of claims 1 to 5, wherein: The cross-sectional area of ​​the first groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction.

7. The sliding component according to claim 4, wherein: The cross-sectional area of ​​the second groove gradually decreases from the upstream side in the sliding direction toward the downstream side in the sliding direction.

8. The sliding component according to any one of claims 1 to 7, wherein: The angle A is greater than or equal to 23° and less than or equal to 40°.

9. The sliding component according to claim 2, wherein: The angle B is greater than or equal to 15° and less than or equal to 30°.

10. The sliding component according to claim 2, wherein: The difference between the angle A and the angle B is greater than or equal to 5° and less than or equal to 30° in absolute value.

11. The sliding component according to claim 10, wherein: The difference between the angle A and the angle B is greater than or equal to 7° and less than or equal to 25° in absolute value.

12. A fixing device comprising: The first rotating body; a second rotating body arranged in contact with the first rotating body; a pressing member disposed on the inner circumferential surface of the second rotating body and pressing the second rotating body toward the first rotating body from the inner circumferential surface of the second rotating body; The sliding member according to any one of claims 1 to 11, interposed between the inner peripheral surface of the second rotating body and the pressing member; and A lubricant is interposed between the inner peripheral surface of the second rotating body and the sliding member.

13. An image forming apparatus comprising: Image holding body; A latent image forming device for forming a latent image on the surface of the image holding body; a developing device for developing the latent image on the toner image using a developer; a transfer device for transferring the developed toner image to a recording medium; and The fixing device according to claim 12 fixes the toner image on the recording medium.

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