JP2022103641A - Belt for image forming apparatus and method for manufacturing the same - Google Patents

Abstract

To provide a belt for an image forming apparatus that can accurately measure a surface state with an optical sensor, specifically, to provide a belt for an image forming apparatus that (1) reflects light largely and (2) reduces a variation in light reflection.SOLUTION: There is provided a belt for an image forming apparatus 1 that has a surface layer 3 composed of a resin cured material on an endless belt 2, the belt for an image forming apparatus having the surface layer with a thickness of 90-210 nm.SELECTED DRAWING: Figure 1

Description

The present invention relates to a belt used in an image forming apparatus. Specifically, in an electrophotographic method, an intermediate transfer belt that carries a toner image that has been primarily transferred to a photoconductor on the surface and conveys it to a region that is secondarily transferred to a recording medium such as paper, or a toner image is transferred. The present invention relates to a transfer transfer belt that carries a recording medium on its surface and conveys it, a paper transfer belt that conveys a recording medium such as paper in an inkjet method, and the like. The belt for an image forming apparatus of the present invention is particularly preferably used in an image forming apparatus using an optical sensor.

A general electrophotographic color image forming apparatus (color printer, color copier, etc.) includes four process cartridges of yellow, magenta, cyan, and black. In each process cartridge, an electrostatic latent image is formed on the photoconductor based on the image data decomposed into four colors, and toner is supplied onto the electrostatic latent image to form a toner image. In the intermediate transfer method, four toner images are sequentially transferred onto an intermediate transfer belt, become a color image on the belt, and then transferred to a recording medium such as paper and fixed. On the other hand, in the tandem method, the recording medium is conveyed to each process cartridge by the transfer transfer belt, and the four toner images are sequentially transferred onto the recording medium and fixed.
On the other hand, the inkjet method does not use a photoconductor and forms an image by dropping ink directly on a recording medium. At this time, the recording medium is sequentially conveyed to four (yellow, magenta, cyan, black) ink cartridges by the paper conveying belt.

The intermediate transfer belt, transfer transfer belt, and paper transfer belt used here are cleaned by the cleaning unit when the surface is contaminated with toner, ink, paper dust, etc., and the timing of this cleaning is measured by an optical sensor. There is. Further, the toner image on the intermediate transfer belt, the position of the recording medium on the transfer transfer belt and the paper transfer belt, and the like are also measured by the optical sensor so that the positional relationship of the four images does not shift (color shift does not occur).
The optical sensor reflects the light emitted from the light emitting element on the surface of the belt, receives the reflected light by the light receiving element, and measures the surface of the belt. In order to improve the accuracy of the optical sensor, the belt for an image forming apparatus is required to have (1) large light reflection and (2) small variation in light reflection. If the light reflection on the belt surface is small, the amount of change in the light reflection when toner or the like adheres is also small, so that it is difficult for the optical sensor to detect the adhesion of toner or the like. Further, if the variation in light reflection is large, the amount of light reflection changes even if toner or the like is not attached, and the cleaning unit or the like may malfunction.

Further, the belt for an image forming apparatus is also required to have good releasability of toner or the like. Further, stain resistance, wear resistance, scratch resistance and the like are also required. A coating agent having various functions is often applied to the belt for an image forming apparatus for the purpose of adding these functions.
However, if the hardness of the coating layer is increased in order to improve scratch resistance, cracks are likely to occur. If the thickness of the coating layer is made thin (1.5 μm or less) in order to prevent cracking, interference fringes may occur due to slight unevenness in the thickness of the coating layer, and the amount of light reflection may change due to the interference fringes. there were. When the amount of light reflection changes, it becomes difficult to control by the optical sensor.

Patent Document 1 is an invention relating to a belt for an image forming apparatus (“endless belt” in Patent Document 1) having high color shift detection performance. The image forming apparatus belt has an average specular reflectance of 5.0% or more in the surface layer (“outermost layer” in Patent Document 1), and the variation thereof is within ± 10% of the average specular reflectance. It is characterized by. Patent Document 1 is characterized in that the surface layer contains an infrared absorber in order to exhibit the performance.
Patent Document 2 is an invention relating to a transfer belt for an image forming apparatus, which has a small variation in intensity with respect to light reflection from an optical sensor. The transfer belt for an image forming apparatus contains an oil-soluble dye such as an azo dye or an anthraquinone dye in the surface layer.

Japanese Unexamined Patent Publication No. 2007-179013 Japanese Unexamined Patent Publication No. 2018-106036

The inventions described in Patent Document 1 and Patent Document 2 are emitted from a light emitting element of an optical sensor by using an infrared absorber or an oil-soluble dye (hereinafter, these are collectively abbreviated as "light absorber"). It suppresses the interference between the light reflected on the outermost surface of the surface layer and the light that has passed through the surface layer and is reflected at the interface between the surface layer and the endless belt. However, in order to reliably suppress the interference, it is necessary to increase the amount of the light absorber added to the surface layer, which leads to a decrease in the scratch resistance of the belt.

An object to be solved by the present invention is to provide a belt for an image forming apparatus capable of accurately measuring a surface state by an optical sensor. More specifically, it is intended to provide a belt for an image forming apparatus having (1) large light reflection and (2) small variation in light reflection.

As a result of diligent studies to solve the above problems, the present inventors have found that by making the surface layer thick in a specific range, the amount of light reflected can be increased, and variations in the amount of light reflected can be suppressed. The finding led to the present invention.

That is, according to the present invention, the belt for the image forming apparatus according to the following [1] to [4] is provided.
[1] An image forming apparatus belt having a surface layer made of a cured resin on an endless belt, wherein the surface layer has a thickness of 90 to 210 nm.
[2] The belt for an image forming apparatus according to [1], wherein the cured resin is a cured product of an ionizing radiation curable compound or a cured product of a thermosetting compound.
[3] The belt for an image forming apparatus according to [2], wherein the cured resin is a cured product of a (meth) acrylic compound due to ionizing radiation.
[4] The belt for an image forming apparatus according to [3], wherein the (meth) acrylic compound is a urethane (meth) acrylate oligomer.

Further, the belt for the image forming apparatus according to [5] to [7] is provided.
[5] The belt for an image forming apparatus according to [2], wherein the cured resin product is a cured product obtained by heating a urethane-based emulsion.
[6] The belt for an image forming apparatus according to any one of [1] to [5], wherein the endless belt is made of a resin composition containing a fluororesin as a main component.
[7] The belt for an image forming apparatus according to any one of [1] to [6], wherein the glossiness (incident angle of 60 °) of the surface layer of the belt for the image forming apparatus is 90 or more.

Further, a method for manufacturing the transfer transfer belt according to [8], the image forming apparatus according to [9], and the belt for an image forming apparatus according to [10] is provided.
[8] A transfer transfer belt using the image forming apparatus belt according to any one of [1] to [7].
[9] An image forming apparatus having the image forming apparatus belt according to any one of [1] to [7].
[10] A belt forming process for forming a cylindrical endless belt having a ten-point average roughness (Rz) of 0.3 to 1.4 μm measured in accordance with JIS B0601-1982, and an ionized radiation curable compound. A coating agent obtained by diluting the coating agent with a solvent or a coating agent obtained by diluting a heat-curable compound with water, if necessary, in a coating step of applying the coating agent to the surface of the endless belt, and after drying the coating agent, ionizing radiation. The method for manufacturing a belt for an image forming apparatus according to any one of [1] to [7], further comprising a curing step of curing by heat in order.

The belt for an image forming apparatus of the present invention has a large amount of light reflection and a small variation in the amount of light reflection, so that uneven glossiness is small, and even if the amount of light reflection changes slightly due to the influence of interference fringes, the optical sensor Therefore, the surface condition can be accurately measured. Further, since the thickness of the surface layer is within a specific range, the surface layer is not easily cracked and the manufacturing cost is reduced. Moreover, since no light absorber is used, the scratch resistance of the belt for the image forming apparatus is good, and the manufacturing cost is low.

Further, when the surface layer is a cured product of an acrylic compound by ionizing radiation, and further, a cured product of a urethane (meth) acrylate oligomer by ionizing radiation, the belt for an image forming apparatus has slipperiness, water repellency, toner releasability, etc. The function of can be easily added. Therefore, it can be suitably used for color printer applications that require colorization of images, high image quality, high speed, and paper compatibility.
Further, when the surface layer is a cured product of a urethane-based emulsion due to heat, the belt for an image forming apparatus can be imparted with folding resistance.

Further, when the endless belt contains a fluororesin as a main component, it is possible to impart performances such as flame retardancy, chemical resistance, and bending resistance to the belt for an image forming apparatus.
Further, since the glossiness of the belt for an image forming apparatus according to the present invention exceeds 90, surface measurement by an optical sensor is easy.
Furthermore, the belt for an image forming apparatus of the present invention is particularly effective when an endless belt having a ten-point average roughness (Rz) of 0.3 to 1.4 μm measured in accordance with JIS B0601-1982 is used. Can be demonstrated.

It is a schematic perspective view which shows one Embodiment of the belt for the image forming apparatus of this invention.

Hereinafter, an embodiment of the present invention will be described. The following description is intended to better understand the gist of the invention, and does not limit the present invention unless otherwise specified. In addition, the shapes and dimensions (length, width, etc.) of the configurations described in the drawings in this application do not necessarily reflect the actual shapes and dimensions, and are appropriately changed for the sake of clarity and simplification of the drawings. ing.

FIG. 1 is a schematic perspective view showing an embodiment of the belt for an image forming apparatus of the present invention. The belt 1 for an image forming apparatus (hereinafter, abbreviated as "belt" if necessary) of the present invention comprises a cylindrical endless belt 2 and a surface layer 3 covering the surface thereof.

<Endless belt>
The material constituting the endless belt is not particularly limited, but is preferably made of a thermoplastic resin in consideration of moldability, for example, a fluororesin, a polyamide resin, a polyester resin, a polycarbonate resin, and a polyamideimide. The based resin, the polyimide based resin and the like can be used alone, in a blend of two or more kinds, or in a multi-layered manner. Among these, the fluororesin, unlike other resins, has flame retardancy by itself, is easy to extrude, and has antifouling property and mold release property, so that it is an image forming apparatus. Ideal for endless belts for plastic belts. Examples of such fluororesins include polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, ethylene-tetrafluoroethylene copolymer, polyhexafluoropropylene, ethylene-vinylidene fluoride copolymer, and vinylidene fluoride. -Tetrafluoroethylene copolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene copolymer and the like can be adopted.

Further, in recent years, as the speed of printers and the like has increased, high elastic modulus has been required for endless belts. If the elastic modulus is low, the belt may stretch during driving and the transfer position may shift. The tensile elastic modulus of the endless belt is preferably 700 MPa or more, more preferably 1,000 MPa or more. In order to increase the tensile elastic modulus of the endless belt, it is advisable to add a reinforcing material such as a flat plate filler or whiskers to the above-mentioned thermoplastic resin. The thickness of the endless belt is preferably 50 to 300 μm, particularly preferably 75 to 200 μm. If the thickness is 50 μm or less, it is difficult to obtain sufficient tensile strength, and if the thickness exceeds 300 μm, the flexibility is deteriorated.

When the belt for an image forming apparatus of the present invention is used for a transfer belt such as an intermediate transfer belt or a transfer transfer belt, the volume resistivity is preferably 105 to ^{10 13} Ω · cm, particularly 10 ⁷ to 10. It is preferably ¹² Ω · cm. In order to control the volume resistivity of the transfer belt within the above range, a conductive material can be blended in the endless belt within a range that does not interfere with the object of the present invention. Conductive materials include electron conductive materials and ion conductive materials.

Examples of the electron conductive material include carbon-based materials such as carbon black, graphite, and carbon nanotubes, conductive polymers such as polyaniline, polythiophene, and polyacetylene, aluminum / zinc oxide, antimony / tin oxide, and indium / tin oxidation. Examples thereof include conductive inorganic particles such as inorganic particles whose surface has been treated with an object, carbon black or the like.
Examples of the ionic conductive material include a polyether ester amide, a polyether ester, a polyether amide, a polyethylene oxide, a polyethylene oxide copolymer, a partially crosslinked polyethylene oxide copolymer, an ionic electrolyte and the like, and these are used alone. , Or two or more types can be used together. As the ion electrolyte, an alkali metal thiocyanate, a phosphate, a sulfate, a halogen-containing oxygen salt, or a tetraalkylammonium salt can be used alone or in combination of two or more. Among these, lithium perchlorate, sodium perchlorate, potassium perchlorate, lithium thiocyanate, sodium thiocyanate, and potassium thiocyanate are preferable.

<Surface layer>
The surface layer 3 of the belt 1 of the present invention is made of a cured resin and has a thickness of 90 to 210 nm, preferably 110 to 190 mm. If the thickness of the surface layer is less than 90 nm or more than 210 nm, the amount of light reflection of the surface layer decreases or the variation of light reflection becomes large, and it becomes difficult to measure the belt surface by the optical sensor.

The cured resin product constituting the surface layer of the present invention is preferably a cured product of an ionizing radiation curable compound or a cured product of a thermosetting compound in consideration of the moldability of the surface layer.
The ionizing radiation curable compound is not particularly limited as long as it is a compound that can be cured by ionizing radiation, and an epoxy compound, a mixture of an epoxy compound and an oxetane compound, an acrylic compound, or the like can be used. In the present invention, an ionizing radiation curable acrylic compound is mentioned as a particularly suitable compound. Among them, urethane (meth) acrylate oligomers are mentioned as a suitable compound. In addition, (meth) acrylic means acrylic or methacrylic.
Urethane (meth) acrylate is a molecule obtained by reacting polyisocyanate with short-chain and long-chain polyols and hydroxyl group-containing (meth) acrylates such as hydroxy (meth) acrylate to form an acrylic group and urethane bond. It is a compound that has.

Examples of the polyisocyanate include toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate and the like. Examples of short-chain polyols include glycerin, pentaerythritol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanezyl, neopentyl glycol, ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol. And so on. Examples of the long-chain polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polycaprolactone diol, polycarbonate diol, or polyester polyol obtained by reacting a short-chain diol with a dicarboxylic acid such as succinic acid and adipic acid. Can be exemplified. Examples of the hydroxyl group-containing (meth) acrylate include hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate.
Further, in the present invention, a polymerizable acrylic compound other than the urethane (meth) acrylate described above can be used in combination.

The thermosetting compound is not particularly limited as long as it is a heat-curable compound, but a urethane-based emulsion in which a urethane-based resin is dispersed in water can be preferably used. Since the urethane-based resin exhibits flexibility, if the surface layer is a urethane-based resin, the belt for an image forming apparatus has excellent folding resistance. The urethane resin is a reaction product of the above-mentioned polyisocyanate and a polyol.
As the thermosetting compound of the present invention, an emulsion of a reaction product (carbonate-based urethane resin) of a polyisocyanate and a carbonate-based polyol is particularly preferable. The carbonate-based urethane resin has higher toughness and better scratch resistance than urethane resins made of other polyols.

Further, the surface layer is a water repellent, a filler, a leveling agent, a conductivity-imparting agent, a photosensitizer, a stabilizer, a polymerization inhibitor, an antifoaming agent, a sagging inhibitor, an adhesion improver, a modifier, and a plasticizer. It may contain various additives such as.

The water repellent can be appropriately selected as needed, but a silicone-based water repellent or a fluorine-based water repellent can be preferably used. As the silicone-based water repellent, a compound having a siloxane bond having a molecular weight of 500 or more is preferably used. Specific examples thereof include dimethylpolysiloxane having hydroxyl groups at both ends, alkylpolysiloxane having an alkyl group at the ends, alkoxy-modified dimethylpolysiloxane, and fluoroalkyl-modified dimethylsilicone. Furthermore, dimethylpolysiloxane having a (meth) acrylic group at the end is incorporated into the crosslinked structure via a chemical bond when the polymerizable acrylic compound is cured, so that the effect can be maintained for a long period of time. It is preferable because it can be done. When an ionizing radiation curable acrylic coating agent containing these water repellents is applied and cured to form a surface layer, the surface free energy of the belt surface decreases, making it difficult for toner to adhere and reducing friction. It has the effect of becoming. Therefore, the releasability between the image forming apparatus belt and the toner is improved, and the transfer efficiency is improved.

The surface layer of the present invention may contain a filler in order to impart scratch resistance to the belt for an image forming apparatus. Although the particle size of the filler is not limited, it is preferably 0.02 μm or more and less than the thickness of the surface layer in consideration of the dispersibility and the surface roughness of the obtained belt, and particularly 0.05 to 0.1 μm. preferable. These fillers may be surface-treated for the purpose of improving dispersibility within a range that does not impair slipperiness. Further, a dispersant can be used as long as the characteristics of the belt are not impaired. The amount of the filler to be blended is preferably 0.5 to 40 parts by weight, particularly preferably 1.0 to 30 parts by weight, based on 100 parts by weight of the ionizing radiation curable compound or the thermosetting compound.

Examples of the filler include fluororubber, fluorocarbon and fluorocarbon in which fluorine is bonded to graphite and graphite, polytetrafluoroethylene, polyvinylidene fluoride, ethylene-tetrafluoroethylene copolymer, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. Fluorine-containing resin powder such as silicone resin, silicone rubber, silicone-based powder such as silicone elastomer, resin powder such as polyethylene, polypropylene, polystyrene, acrylic resin, nylon resin, phenol resin, epoxy resin, silica, alumina, oxidation Examples thereof include inorganic powders such as titanium and magnesium oxide. These fillers may be surface-treated to improve their dispersibility in the coating agent, or may be used alone or in combination.

<Belt for image forming device>
The image forming apparatus belt of the present invention preferably has a glossiness (incident angle of 60 °) of the surface layer of 90 or more, and more preferably 95 or more. When the glossiness is less than 90, the amount of light reflected on the surface layer is small, and the amount of change in light reflection when toner or the like adheres is also small, so that it is difficult for the optical sensor to detect the adhesion of toner or the like. For the glossiness of the surface layer in the belt of the present invention, the average value of the values measured at three points (12 points in total) different in the length direction in the region where the belt is divided into four at equal intervals in the circumferential direction is used. ..
Further, in the belt of the present invention, the difference between the maximum value and the minimum value of the values measured at the above 12 points is preferably 12 or less, particularly preferably 10 or less, and further preferably 8 or less. If the difference in glossiness exceeds 12, the variation in light reflection becomes large, the amount of light reflection changes even if toner or the like is not attached, and the cleaning unit or the like may malfunction.

<Manufacturing method of belt for image forming apparatus>
The method for producing a belt of the present invention requires (1) a belt forming step for forming a cylindrical endless belt, and (2) a coating agent obtained by diluting an ionizing radiation curable compound with a solvent, or a heat-curable compound. A coating step of applying a coating agent diluted with water according to the above to the surface of the endless belt, and (3) a curing step of drying the coating agent and then curing it by ionizing radiation or heat are provided in this order.

(1) Belt molding Step The resin for molding the above-mentioned endless belt is molded into the shape of the endless belt as shown in FIG. 1 by an extrusion molding method, a centrifugal molding method, a dipping method or the like. As a molding method capable of continuous production relatively easily, the present invention proposes an extrusion molding method using an extruder equipped with an annular die. An endless belt can be obtained by extruding a resin from an annular die into a tube shape by the method and cutting the obtained tube to a predetermined length.

When the endless belt using the annular die has a relatively small ten-point average roughness (Rz) measured in accordance with JIS B0601-1982, the glossiness is obtained when the surface layer is provided on the surface of the endless belt. There is an inherent problem that unevenness is likely to occur. The present invention can exert its effect when used for an endless belt having a ten-point average roughness (Rz) of 0.3 to 1.4 μm, particularly 0.4 to 0.8 μm. Further, an endless belt having an arithmetic mean roughness (Ra) of 0.05 to 0.2 μm, particularly 0.05 to 0.15 μm, and further 0.06 to 0.12 μm, measured in accordance with JIS B0601-1982. The effect can be exerted in.
The ten-point average roughness (Rz), arithmetic average roughness (Ra), and maximum height (Rmax) of the present invention are all arbitrary on the belt surface using Surfcom 570A (manufactured by Tokyo Precision Co., Ltd.). It is an average value of the values measured at the five points of. The stylus has a tip radius of curvature of 2 μm, and is measured at a cutoff value of 0.8 mm, a measurement length of 2.5 mm, and a velocity of 0.3 mm / sec.

(2) Coating process Prior to the coating process, a coating liquid is prepared.
Specifically, when the above-mentioned cured resin is (i) a cured product of an ionizing radiation curable compound, the ionizing radiation curable compound, various additives and fillers to be blended as necessary, and ionizing radiation curing are used. The photopolymerization initiator for curing the type compound by ionizing radiation is diluted with a solvent to obtain a coating liquid.

Examples of the photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1-. Hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone, 2,4,6 -Trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, benzophenone, o-benzoylmethyl benzoate, hydroxybenzophenone, 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4- Diethylthioxanthone, 2,4-dichlorothioxanthone, 2,4,6-tris (trichloromethyl) -S-triazine, 2-methyl-4,6-bis (trichloro) -S-triazine, 2- (4-methoxyphenyl) ) -4, 6-Bis (trichloromethyl) -S-triazine, iron-allene complex, titanosen compound and the like, and it is preferable to use one or a combination of two or more of these.

The blending amount of the solvent can be appropriately adjusted according to the desired viscosity of the coating agent, the coating thickness, and the like. For example, the amount of the solvent is 70 to 2000 parts by weight, preferably 300 to 1500 parts by weight, based on 100 parts by weight of the polymerizable compound in the ionizing radiation curable compound. If the amount of the solvent is less than 70 parts by weight, the coatability, handleability and the like are deteriorated, and it becomes difficult to thin the surface layer. If it exceeds 2000 parts by weight, it takes time to dry. The viscosity of the coating agent is preferably 50 mPa · s or less in order to obtain a surface layer having a thin thickness and little change in film thickness.

When the cured resin product described above is (ii) a cured product obtained by heating the urethane emulsion, the urethane resin, water, and an emulsifier are mixed to prepare a urethane emulsion, and then water is further added as necessary. Can be diluted to obtain a coating solution. The viscosity of the coating agent is preferably 200 mPa · s or less in order to obtain a surface layer having a thin thickness and little change in film thickness.
Emulsions include a forced emulsification type that uses a surfactant as an emulsifier and a self-emulsification type that introduces a hydrophilic group into the resin. The urethane-based emulsion of the present invention is preferably a self-emulsifying emulsion in which there is no concern that the surfactant bleeds out after drying. As the self-emulsifying hydrophilic group, an anion-based, cationic-based, or nonionic-based group may be used.

Examples of the method of applying the coating agent to the surface of the endless belt include a roll coat, a bar coat, a dip coat, and a spray coat. Among them, the spray coating method is particularly suitable as the coating method of the present invention because it is excellent in film thickness uniformity and the roll coating method has less loss of the coating agent.

(3) Curing Step After applying the coating agent on the endless belt, the coating agent is dried and the surface layer is cured by ionizing radiation or heat to complete the belt of the present invention. The ionizing radiation in the present invention is not particularly limited, and examples thereof include ultraviolet rays, electron beams, alpha rays, beta rays, gamma rays, X-rays, and neutron rays. In the case of ultraviolet rays, the irradiation amount is usually 100 to 15,000 mJ / cm2, preferably 300 to 8,000 mJ / cm2.
Further, when it is cured by irradiating it with ionizing radiation, it is not necessary to heat it at a high temperature unlike curing by heat, and it has an advantage that the transfer belt for an image forming apparatus is not damaged by heat.

Hereinafter, the effects of the present invention will be described in more detail with reference to Examples. The image forming apparatus belts produced in Examples and Comparative Examples were evaluated for the following items, and the results are shown in Table 1.
<Glossiness>
The glossiness is a measured value when a glossiness meter gloss checker IG-320 manufactured by HORIBA, Ltd. is used and the incident angle is set to 60 ° and the light receiving angle is set to 60 °. The belt was divided into four parts at equal intervals in the circumferential direction, and measurements were taken at three points (12 points in total) different in the length direction.

(Example 1)
Mix 5 parts by weight of the polyethylene oxide copolymer and 0.5 part by weight of lithium perchlorate with 100 parts by weight of polyvinylidene fluoride (with a tensile modulus of 1,400 MPa) and knead with a twin-screw kneader. The pellet was formed to obtain a resin composition for an endless belt.
Using a device with an annular die attached to the tip of an extruder with a cylinder diameter of 50 mm, the resin composition for endless belts is extruded into a tube shape, then cut into a length of 400 mm, with a thickness of 100 μm, a circumference of 850 mm, and a width of 400 mm. Created an endless belt.
The surface roughness of the endless belt was adjusted to JIS B0601-1982 using Surfcom 570A (Tokyo Precision Co., Ltd.), with a stylus tip radius of 2 μm, a cutoff value of 0.8 mm, a measurement length of 2.5 mm, and a speed. It was measured at 0.3 mm / sec. When the measurement was performed on five places on the surface of the endless belt and the average value was obtained, it was Ra = 0.08 μm, Rmax = 0.90 μm, and Rz = 0.57 μm.

Next, as an ionized radiation curable acrylic compound, 97 urethane acrylate oligomers (manufactured by Negami Kogyo) having a molecular weight of 70,000 and a molecular weight per (meth) acrylic group of 1,380 (hereinafter referred to as (meth) acrylic equivalent). Methyl isobutyl ketone as a solvent is added to parts by weight, 2-hydroxy-2-methyl-1-phenyl-propane-1-one 2.85 parts by weight as a photopolymerization initiator, and 0.15 parts by weight of a silicone-based water repellent. 1000 parts by weight was added and uniformly dissolved to prepare a coating agent containing an ionized radiation curable acrylic compound for the surface layer.
The obtained coating agent was applied to the surface of the endless belt by a roll coating method, dried, and then irradiated with ultraviolet rays at 3,000 mJ / cm ² to form a surface layer having a thickness of 110 nm. Then, the belt was cut to a width of 350 mm to obtain a belt for an image forming apparatus of Example 1. The evaluation results of the belt are shown in Table 1.

(Examples 2 to 4, Comparative Examples 1 to 6)
A belt was obtained in the same manner as in Example 1 except that the thickness of the surface layer was changed as shown in Table 1. The evaluation results of each belt are shown in Table 1.

The belts of Examples 1 to 3 had an average glossiness of more than 90 and a large amount of light reflection. Further, the difference between the maximum value and the minimum value of the glossiness was less than 10, and the variation in the amount of light reflection was small. Therefore, the surface condition can be accurately measured by the optical sensor. Since the average glossiness of the belts of Comparative Examples 1 to 3 and Comparative Example 5 is less than 90, the amount of light reflection is small. Although the belts of Comparative Examples 4 and 6 had an average glossiness of more than 90, the difference in glossiness was large and the amount of light reflection was large.

1 Belt for image forming equipment 2 Endless belt 3 Surface layer

Claims (10)

An image forming apparatus belt having a surface layer made of a cured resin on an endless belt, wherein the surface layer has a thickness of 90 to 210 nm. The belt for an image forming apparatus according to claim 1, wherein the cured resin is a cured product of an ionizing radiation curable compound or a cured product of a thermosetting compound. The belt for an image forming apparatus according to claim 2, wherein the cured resin is a cured product of a (meth) acrylic compound by ionizing radiation. The belt for an image forming apparatus according to claim 3, wherein the (meth) acrylic compound is a urethane (meth) acrylate oligomer. The belt for an image forming apparatus according to claim 2, wherein the cured resin product is a cured product obtained by heating a urethane-based emulsion. The belt for an image forming apparatus according to any one of claims 1 to 5, wherein the endless belt is made of a resin composition containing a fluororesin as a main component. The belt for an image forming apparatus according to any one of claims 1 to 6, wherein the glossiness (incident angle of 60 °) of the surface layer of the belt for an image forming apparatus is 90 or more. A transfer transfer belt according to any one of claims 1 to 7, wherein the belt for an image forming apparatus is used. An image forming apparatus having the image forming apparatus belt according to any one of claims 1 to 7. A belt forming process for forming a cylindrical endless belt having a ten-point average roughness (Rz) of 0.3 to 1.4 μm measured in accordance with JIS B0601-1982, and a belt forming process.
A coating step of applying a coating agent obtained by diluting an ionizing radiation curable compound with a solvent or a coating agent obtained by diluting a thermosetting compound with water, if necessary, to the surface of the endless belt.
A curing step in which the coating agent is dried and then cured by ionizing radiation or heat.
The method for manufacturing a belt for an image forming apparatus according to any one of claims 1 to 7, wherein the belts for an image forming apparatus are provided in order.

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