JP2002145429A - Seamless belt with guide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seamless belt with a guide having suppressed slight meandering due to push-up or ride-on and a sufficiently long life. SOLUTION: The seamless belt with the guide to be mounted between plural rolls comprise guide ribs provided on the inner peripheral face of a belt body and adapted to be fitted into guide grooved portions on the outer peripheral faces of the rolls. The guide rib is formed of a laminate which has a thickness of 0.1-5 mm and an apparent hardness of 85-100 Hs. The laminate consists of a film layer having a tensile elastic modulus of 1000-8000 MPa and an elastic material layer. The laminate is bonded at its film layer side to the inner peripheral face of the belt body with an adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seamless belt with a guide used for a photoreceptor, a charging device, a transfer device, a fixing device, or a transport device in an image forming apparatus and the like. The present invention relates to a seamless belt with a guide in which a guide rib fitted to a guide groove on an outer peripheral surface of the roll is provided on an inner peripheral surface of the belt.

[0002]

2. Description of the Related Art Generally, an electrophotographic image forming apparatus includes a developing device, a charging device, a transfer device, a fixing device, a transporting device, and the like. In recent years, a seamless belt has been frequently used in these devices. This type of seamless belt is stretched between two or three rolls, and is used for moving an electrostatic latent image, transferring a toner image, or transporting a recording sheet or the like. By the way, if the seamless belt does not meander accurately and does not meander, it may interfere with the transfer or the like. The roundness, straightness, etc. of the rolls are sufficiently required for the high-precision orbiting of the seamless belt, but the pursuit of such accuracy is generally limited. For this reason, it has been considered to attach a guide to the belt body. In a conventional seamless belt with a guide, meandering is prevented by fitting a guide rib provided on the inner peripheral surface of the belt into a guide groove provided on the peripheral surface of the roll (see Japanese Patent Application Laid-Open No. HEI 4-4-2).
333457, JP-A-7-187435,
JP-A-8-99706, JP-A-11-33817
4, JP-A-2000-1237, JP-A-200
No. 0-39806).

[0003]

The guide ribs of the seamless belt with a guide are provided on the inner peripheral surface of the belt, and a certain degree of compression and elongation is required at the bent portion near the roll because of the circumference. . For this reason, an elastomer or the like having rubber elasticity at normal temperature is conventionally used for the guide rib. However, if the guide ribs are easily and easily deformed, the guide ribs may not be accurately guided due to the inside of the groove, and may cause the belt to slightly oscillate. If the conventional guide rib and the guide groove are simply fitted together, such fluctuations occur frequently, causing a serious problem that the guide rib rises, runs up, and chatters. Also, in the manufacturing process, if the guide ribs are bonded to the inner peripheral surface of the belt with an adhesive while being pressed, the deformed guide ribs return to their original state after bonding, causing permanent deformation or shearing with the belt. Stress is generated, and stress is always generated between the guide and the belt. Such a stress on the belt, in combination with the above-described inconvenience, may cause belt peeling, crack the end of the belt, or cause breakage, which is a factor that deteriorates the durability of the belt. I have.

Accordingly, the present invention has been made in view of the above-mentioned problems, and delicate meandering due to a belt lifting phenomenon, a riding phenomenon, and the like can be suppressed, and the life of the belt can be sufficiently extended. It is an object to provide a seamless belt with a guide.

[0005]

According to the first aspect of the present invention, there is provided a seamless belt provided between a plurality of rolls for solving the above-mentioned problems, the guide groove being formed on an outer peripheral surface of the roll. In a seamless belt with a guide, in which a guide rib fitted to the strip is provided on the inner peripheral surface of the belt main body, the guide rib has a thickness of 0.1 to 0.1 mm.
It is in the range of 5 mm and has an apparent hardness of 85 to 100H.
s, the laminate comprises a film layer having a tensile modulus in the range of 1000 to 8000 MPa, and an elastic material layer, and the laminate is formed of the belt body on the film layer side. The object has been achieved by providing a seamless belt with a guide, which is joined to the peripheral surface with an adhesive. The number of the guide ribs is one or more, and the number can be appropriately selected. The guide ribs may be mounted on the inner peripheral surface of the belt at any position such as the central portion of the belt and both end portions of the belt, and are generally near both end portions of the belt. The pressure-sensitive adhesive is one that chemically and physically cures the pressure-sensitive adhesive layer. In particular, a resin that can be positively cured by heat or ultraviolet irradiation is desirable.

In the above seamless belt with guide,
Since the guide ribs are formed of a deformable laminate having an apparent hardness of 100 Hs or less, the guide ribs are smoothly bent at the rolls according to the rotation of the belt, and are sufficiently fitted to the guide grooves of the rolls. On the other hand, the apparent hardness of the laminate is 85Hs.
As described above, since the guide ribs are given a predetermined hardness, the rolls are less swayed in the guide groove portions, and the belt is given a stable circling state. For this reason, it is possible to suppress a belt rising phenomenon, a riding phenomenon, and a chatter phenomenon. Further, the pressure-sensitive adhesive cures with time, and the inner peripheral surface of the belt body and the film layer surface of the laminate are sufficiently bonded. For this reason, the laminated body can be accurately attached to the inner peripheral surface of the belt main body without being pressed, and no permanent distortion or shear stress occurs between the belt main body and the laminated body. For this reason, sufficient durability can be expected from the seamless belt with a guide.

[0007]

Embodiments of the present invention will be described below in detail. FIG. 1 is a schematic perspective view showing an embodiment of a seamless belt with a guide according to the present invention. FIG. 2 is a sectional view of a guide rib portion of the seamless belt with guide according to the present invention. FIGS. 3A and 3B are enlarged cross-sectional views of a guide rib showing another embodiment of the seamless belt with guide according to the present invention. FIG. 4 is a schematic diagram of an image forming apparatus provided with a seamless belt with a guide.

As shown in FIGS. 1 and 2, a seamless belt with a guide according to the present embodiment includes a plurality of rolls 3 and 3.
An endless seamless belt 1 laid between the guide belts, and a guide rib 11 fitted to a guide groove 2 formed on the peripheral surface of the roll 3 is attached to the inner peripheral surface of the belt body 10. The guide rib 11 is attached with a predetermined width in a direction perpendicular to the transverse direction of the belt main body 10, and in the present embodiment, the guide rib 11 has a rectangular cross section. Therefore, the guide groove 2 is accurately formed in a groove perpendicular to the roll axis, and the cross-sectional shape of the guide groove 2 is rectangular. Although only one guide rib 11 is formed in FIG. 1, two or more guide ribs 11 may be formed. Although the guide rib 11 is provided near the side end of the belt main body 10,
It may be provided at the center of the belt body 10.

The belt body 10 is endlessly formed by centrifugal molding, extrusion molding, or injection molding using a predetermined resin material. The material of the belt body 10 is PET, PB
T, polyester resin such as PEN, α-polyolefin resin, cyclic polyolefin resin, polyimide resin, polyamide resin, polyamideimide resin, fluorine resin, polysulfone, polyethersulfone,
Polycarbonate, aramid resin, polyetheretherketone (PEEK), epoxy resin, cross-linked polyester resin, melamine resin and the like are exemplified. The guide-equipped seamless belt is applied as an intermediate transfer belt, but can be suitably applied to a developing device, a charging device, a transfer device, a fixing device, a transport device, and the like in an image forming apparatus. For this reason, the width of the belt main body 10 is appropriately selected according to the function of the use device. Further, various characteristics are given to the belt main body 10 in accordance with the functions of the device.

For example, the belt body 10 may be required to have a certain degree of conductivity. In this case, a conductivity-imparting agent is appropriately added. Examples of such a conductivity-imparting agent include powders of metals, alloys, such as needle-like, spherical, plate-like, amorphous, etc., carbon powders such as acetylene black, Ketjen black, furnace black, natural graphite, artificial graphite, and expansion. Examples include graphite powder such as graphite, ceramic powder, and various types of particles whose surfaces are metal-plated. The shape and size of the particles are spherical or irregular, and are 0.01 to 10 μm.
m is desirable. The amount of the conductivity-imparting agent may be appropriately adjusted depending on the desired conductivity, but is desirably selected from the range of 1 to 25% by volume. If the content is less than 1% by volume, the distance between the conductive substances becomes large, and there is a possibility that conductivity does not appear. If it exceeds 25% by volume, there is a risk that the mechanical strength of the belt body 10 will be adversely affected.

As a method for dispersing the conductivity-imparting agent in the resin material, a known dispersion method is appropriately used. Specifically, a method suitable for the properties of the resin material, such as a mixing roll, a pressure kneader, an extruder, a three roll, a homogenizer, a ball mill, a bead mill, or the like is employed. Various additives such as a plasticizer, a colorant, an antistatic agent, an antioxidant, a reinforcing filler, a reaction aid, and a reaction inhibitor are added as necessary.

As shown in FIG. 2, the guide rib 11 of the seamless belt with guide according to the present invention comprises a film layer 21 and an elastic layer 23, and has a width of the guide rib 11, that is, a laminate 25. Is appropriately selected according to the function of the apparatus to which the seamless belt with guide is applied. The thickness of the laminate 25 is in the range of 0.1 to 5 mm, preferably in the range of 0.2 to 3 mm, and more preferably in the range of 0.5 to 2 mm. If the thickness of the laminate 25 is less than 0.1 mm, the guide rib 11
Cannot maintain a sufficient thickness.
From the guide groove 2. The laminated body 2
If the thickness of 5 exceeds 5 mm, the flexibility of the entire laminate 25 deteriorates, shear stress is easily generated in the guide ribs 11 and the belt main body 10, and the circulating property and durability deteriorate.

The apparent hardness of the laminate 25 including the film layer 21 and the elastic layer 23 is in the range of 85 to 100 Hs, preferably in the range of 85 to 95 Hs, and more preferably in the range of 85 to 90 Hs. It is. If the apparent hardness of the laminated body 25 is less than 85 Hs, the laminated body 25 is easily deformed, and there is a possibility that the guide ribs 11 may not be accurately fitted due to the inside of the guide groove 2 of the roll 3. is there. The apparent hardness of the laminate 25 is 100 Hs.
If it exceeds, the deformation of the guide ribs 11 is insufficient, so that the bending around the circumference of the roll is poor, and a shear stress is generated to deteriorate the durability. Here, the apparent hardness of the laminate 25 refers to the thickness of the laminate 25 used and the film layer 21.
This is the JISA hardness Hs measured by pressing from the surface.

The film layer 2 in the laminate 25
The tensile modulus of 1 is in the range of 1000 to 8000 MPa, preferably in the range of 1200 to 6000 MPa, and more preferably in the range of 1500 to 4500 MPa. The tensile elastic modulus of the film layer 21 is 1000M
If less than Pa, the elasticity of the laminate 25 is too large,
The belt body 10 and the guide rib 11 may be displaced from each other during driving. When the tensile modulus of the film layer 21 exceeds 8000 MPa, the laminate 25
The overall rigidity is increased, and distortion and shear stress are easily generated between the belt main body 10 and the guide ribs 11 during orbit, and the life of the belt main body 10 may be shortened.

The thickness of the film layer 21 in the laminate 25 is preferably in the range of 2 to 500 μm,
In particular, the thickness is preferably 50 to 300 μm. If the thickness is less than 2 μm, it is difficult to give the laminate 25 a desired rigidity. If the thickness exceeds 500 μm, the rigidity of the film becomes too high, and the belt main body 10 is hindered from bending near the joining of the guide ribs 11,
Unexpected shearing force is likely to be generated, resulting in poor orbit and breakage. Examples of the material of the film layer 21 include α-polyolefin resins such as polypropylene, PET, PB
Examples include polyester resins such as T and PEN, polyamide resins, vinyl chloride resins, polycarbonates, aramid resins, polyetheretherketone (PEEK), and the like.

The laminated body 25 is required to have an appropriate rubber elasticity because it is repeatedly bent while being fitted to the guide groove 2 of each roll 3 when the belt body 10 rotates. Therefore, the elastic layer 23 fixed to the surface of the film layer 21 is an elastically deformable elastomer. Specific examples include, but are not limited to, urethane-based elastomers, silicone-based elastomers, fluororesin-based elastomers, styrene-based elastomers, and α-olefin-based elastomers. Among the above elastomers, urethane-based elastomers are particularly excellent in mechanical properties.

The laminate 25 is bonded to the inner peripheral surface of the belt body 10 with an adhesive 27 on the film layer 21 side.
The adhesive 27 is usually used for the film layer 2 of the laminate 25.
The coating is applied to one surface, and the laminate 25 and the belt body 10 are accurately positioned with respect to each other. Then, the laminate 25
Is bonded to the inner peripheral surface of the belt body 10 via an adhesive 27. The pressure-sensitive adhesive is a pressure-sensitive adhesive 27 that is physically or chemically cured, and the final pressure-sensitive adhesive strength between the laminate 25 and the belt body is desirably 14 kg · f / cm ² or more. The thickness of the pressure-sensitive adhesive 27 is in the range of 5 to 100 μm, preferably in the range of 5 to 50 μm, more preferably 10 to 50 μm.
３０30 μm. The thickness of the adhesive 27 is 5 μm.
If it is less than m, sufficient bonding strength between the laminate 25 and the belt body 10 cannot be provided. If the thickness of the pressure-sensitive adhesive exceeds 100 μm, the long-term deviation in the shearing direction, that is, the resistance to so-called creep is inferior, and the meandering prevention effect may be deteriorated in long-term use.

In the seamless belt with guide according to the present invention, the film layer 21 and the elastic layer 2 of the laminate 25 are provided.
3 and the inner peripheral surface of the belt body and the film layer 21.
It is desirable that the bonding strength be larger than that of the surface. That is, the film layer 21 and the elastic layer 2 forming the laminate 25
3 and the guide ribs 11 are fixed to the belt body 1.
When peeling from 0, the laminate 25 is not broken, and the belt body 10 and the film layer 21 peel off first. Since the laminated body 25 does not break before the guide ribs 11 are peeled off, the rigidity of the laminated body 25 is maintained even in the event of misalignment or the like, and the deterioration of the meandering prevention effect can be minimized. Since the breakage of the peripheral member can be prevented by the broken pieces.

In the seamless belt with guide according to the present invention, the adhesive 27 is desirably an ultraviolet curable resin which is cured by irradiation of ultraviolet rays. If the pressure-sensitive adhesive 27 is an ultraviolet-curable resin, the laminate 25 can be stuck to the belt body 10 at an accurate position when the pressure-sensitive adhesive 27 is uncured. At this time, the laminate 2
It is not necessary to join while pressing 5. The laminated body 25
By irradiating the laminated body 25 on the inner peripheral surface of the belt body 10 by irradiating the laminated body 25 with the ultraviolet rays after accurately positioning and mounting the belt body 10 on the belt body 10, the laminated body 25 is accurately and reliably joined. Therefore, no permanent distortion or shear stress is generated between the belt main body 10 and the guide rib 11 during joining. In the seamless belt with guide 1, at least one of the belt main body 10 and the laminate 25 is made of an ultraviolet-permeable material. That is, if the belt main body 10 is an ultraviolet transmitting material, the adhesive 27 can be reliably cured by efficiently irradiating ultraviolet rays from the belt main body 10 side. Further, the laminate 25, that is, the film layer 21
If the elastic layer 23 and the elastic layer 23 are made of an ultraviolet-permeable material, the adhesive 27 is irradiated with ultraviolet light efficiently from the laminate 25 side.
Can be surely cured.

When the guide-equipped seamless belt according to the present invention is attached to an image forming apparatus, a predetermined hardness is given to the laminated body 25 of the guide ribs 11, so that the guide ribs 11 are suitable during the rotation of the roll. It shows bending and is fitted and guided exactly in the guide groove. The guide rib 11 is less swayed in the guide groove, and the guide rib 11 gives the belt body 10 a stable circling state. In addition, the guide ribs 11 are bonded to the inner peripheral surface of the belt main body 10 through an adhesive without causing permanent distortion, shear stress or the like at the time of bonding. That is, the laminated body 25 can be accurately attached to the inner peripheral surface of the belt main body 10 without being pressed, and no distortion or shear stress is generated between the belt main body 10 and the laminated body 25. Therefore, sufficient durability can be expected from the seamless belt with guide 1.

In another seamless belt with a guide according to the present invention, the laminated body has a substantially V-shaped cross section,
The film layer is formed in a trapezoidal shape or a convex shape, and the width of the film layer is equal to or wider than the width of the elastic material layer.
As shown in FIGS. 3A to 3C, the cross-sectional shape of each of the guide ribs 11 in each of the laminates 31, 32, and 33 is substantially V-shaped, trapezoidal, or convex. The width W1 is equal to or slightly wider than the elastic material layer width w2. In the guide rib 11, the cross sections of the guide groove portions 34, 35, 36 of the roll are also formed in shapes corresponding to the respective cross sections, and the thickness portions of the film layer 21 and the elastic material layer 23 of the laminate are formed. Completely and accurately fit into the respective guide grooves 34, 35, 36.
In this case, the guide rib 11 is such that the elastic material layer 23 of each of the laminates 31, 32, 33, which is the insertion distal end, is completely fitted into the respective guide groove portions 34, 35, 36, and accordingly, at the proximal end. A certain film layer 21 has guide groove portions 34, 3
Fits securely around the insertion holes 5 and 36. The above film layer 2
Unlike the elastic material layer 23, the elastic member 1 does not easily cause elastic deformation because it is relatively hard. For this reason, the guide rib 11, particularly the film layer 21, is guided accurately without depending on the inside of the groove, and the belt main body 10 does not delicately swing. Since the guide ribs 11 and the guide groove portions 2 are securely fitted to each other, there is no occurrence of a rising phenomenon, a riding phenomenon, and a chattering phenomenon of the seamless belt with a guide.

[0022]

Next, the present invention will be described in more detail with reference to Examples and Comparative Examples. Note that the seamless belt with guide according to the present invention is not limited to the following embodiments. Each constituent member of the seamless belt with guide in each example and comparative example,
And its physical properties are shown in Table 1. The physical properties were measured according to the following methods. In Table 1, PI is polyimide, PAI is polyamideimide, PC is polycarbonate, and PET is polyethylene terephthalate. In Reference Example 1, the same acrylic pressure-sensitive adhesive layer was provided on both sides of the film layer. Reference Example 1 is an embodiment that satisfies claim 1, but cannot be the embodiment of claim 2. 1. Measurement of apparent hardness: The laminate 25 was placed on a flat glass plate having a thickness of 5 mm with the film layer side facing up,
Using an A-type spring-type hardness tester specified in JIS K6301, five-point measurement is performed, and an average value is obtained.
The apparent hardness was used. In the case of a type A spring hardness tester exceeding 100, it was measured using a type C tester and converted to an A type value. 2. Measurement of tensile modulus: JIS only for film layer
A tensile test was performed by the method described in K 7127 to determine the tensile modulus. In addition, the test piece shape is a No. 2 type test piece,
The test speed was 1 mm per minute.

[0023]

[Table 1]

The seamless belts with guides of the above Examples and Comparative Examples were used as intermediate transfer belts of an image forming apparatus 40 as shown in FIG. Photoconductor 41 of image forming apparatus
Is formed on the photosensitive member 41, the toner image on the photosensitive member 41 is transferred to the seamless belt with guide 10, driven by the rolls 3 and 42, and further transferred to the recording material 43. For each of the above Examples and Comparative Examples, 1 A4 size
A print test was performed on 100,000 sheets, and evaluation was performed on belt damage, image displacement, and guide peeling. In the example, the printing test was further continued up to 200,000 sheets. The evaluation results are shown in Table 2 below.

[0025]

[Table 2]

From the above, it can be understood that the comparative examples 1 and 2 have the apparent hardness of the laminated body outside the range of the present invention and are liable to damage the belt as compared with the examples. In addition, from Example 1 and Reference Example 1, it can be seen that when both surfaces of the film layer are joined with the same adhesive, the guide rib is likely to shift. Further, the damage of the belt at 120,000 sheets in Reference Example 1 was caused by the guide rib being peeled and broken, and this was caught between the belt body and the roller.

[0027]

As described above, according to the seamless belt with guide according to the present invention, the guide rib has a thickness in a predetermined range and an apparent hardness of 85 to 100H.
s, the tensile elastic modulus of the laminate is in the range of 1000 to 8000 MPa, and the film layer is made of an elastic material layer. In addition to being suppressed, the service life of the belt can be sufficiently extended.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a guide seamless belt according to the present invention.

FIG. 2 is a sectional view of a guide rib portion of the seamless belt with guide according to the present invention.

FIGS. 3 (a) and 3 (b) are enlarged cross-sectional views of guide ribs showing another embodiment of the seamless belt with guide according to the present invention.

FIG. 4 is a schematic view of an image forming apparatus provided with a seamless belt with a guide.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Seamless belt with a guide 2 Guide groove | channel part 3 Roll 10 Belt main body 11 Guide rib 21 Film layer 23 Elastic material layer 25 Laminated body 27 Adhesive

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/16 G03G 15/16 3F024 15/20 15/20 3F049 21/00 350 21/00 350 F term ( Reference) 2H003 BB11 CC04 2H032 BA09 BA18 2H033 BA11 BA12 2H035 CB06 CD09 CD11 CF02 3F023 AA05 BA02 BB01 BC01 GA01 GA03 3F024 AA11 CA04 CA08 DA07 3F049 AA01 BA03 BB11 CA14 LA01 LB03

Claims (3)

[Claims] A seamless belt provided between a plurality of rolls, wherein a guide rib fitted on a guide groove on an outer peripheral surface of the roll is provided on an inner peripheral surface of the belt body. In the belt, the guide rib is formed of a laminate having a thickness in a range of 0.1 to 5 mm and an apparent hardness in a range of 85 to 100 Hs, and the laminate has a tensile modulus of 1000 to 8;
A seamless belt with a guide, comprising a film layer in the range of 000 MPa and an elastic material layer, wherein the laminate is bonded to the inner peripheral surface of the belt body with an adhesive on the film layer side. 2. The seamless belt with a guide according to claim 1, wherein the bonding strength between the film layer and the elastic material layer of the laminate is larger than the bonding strength between the inner peripheral surface of the belt and the film surface. Guided seamless belt. 3. The seamless belt with a guide according to claim 1, wherein the laminated body has a substantially V-shaped, trapezoidal, or convex cross-sectional shape. A seamless belt with a guide, wherein the width is formed to be equal to or wider than the width of the elastic material layer.