JP6617543B2 - Intermediate transfer belt manufacturing apparatus and manufacturing method - Google Patents

Description

  The present invention relates to an intermediate transfer belt manufacturing apparatus and manufacturing method.

  The image forming apparatus transfers the toner image formed on the photosensitive member to an intermediate transfer member, and then transfers the toner image to a recording medium such as plain paper. The intermediate transfer member is, for example, an endless intermediate transfer belt having a base layer made of crystalline resin and a surface layer made of photocurable resin disposed on the base layer. Until now, the manufacturing method of the film which has a base material layer and the layer made from the photocurable resin formed on the said base material layer is known (for example, refer patent document 1).

  In the method for producing a film described in Patent Document 1, first, a support body (base material layer) wound in a coil shape is sent out. Subsequently, the coating material of the said coating material is formed by apply | coating the coating material containing a photopolymerizable monomer on one surface of the said base material layer, and making it dry. Next, the coating film is irradiated with ultraviolet light (active light) to photopolymerize the photopolymerizable monomer. Since the base material layer immediately after the ultraviolet light irradiation is at a high temperature, the base material layer is cooled by a cooling roller in contact with the base material layer after photopolymerization. Thereby, the layer made from a photocurable resin can be formed on a base material layer.

JP 2013-208855 A

  However, in the film manufacturing method described in Patent Document 1, the base material layer is cooled after the coating film is irradiated with ultraviolet light. For this reason, when a crystalline resin is used as the material of the base material layer, the crystallinity of the base material layer changes immediately after the irradiation of ultraviolet light and before the base material layer is cooled. There is. As a result, the flexibility of the film may be reduced or creep may occur.

  The subject of this invention is providing the manufacturing apparatus and manufacturing method of an intermediate transfer belt which can suppress that the crystallinity of a base material layer changes with the heat | fever supplied by irradiation of actinic light. .

  An intermediate transfer belt manufacturing apparatus according to the present invention is an endless intermediate transfer belt manufacturing apparatus having a base layer made of a crystalline resin and a surface layer made of a photocurable resin, the base layer and Two or more first rollers for supporting an endless belt having a coating film of a photocurable coating material for a surface layer disposed on the outer peripheral surface of the base material layer, and at least one of the first rollers A rotational drive device for rotationally driving one; an actinic ray irradiation device disposed at a position for irradiating the actinic ray to the coating film of the endless belt supported by the first roller; and the activity A second roller disposed at a position facing the light beam irradiating device and abutting on the endless belt supported by the first roller from a side opposite to the active light beam irradiating device; 1 roller and 2nd roller Each incorporates, having a cooling device for cooling the substrate layer.

  The method for producing an intermediate transfer belt according to the present invention is a method for producing an endless intermediate transfer belt having a base layer made of a crystalline resin and a surface layer made of a photocurable resin, Two or more first rollers that pivotally support an endless belt having a coating film of a photocurable surface layer coating disposed on the outer peripheral surface of the base material layer are rotationally driven, and the endless belt is The step of moving on the endless track, the step of irradiating the coating film of the endless belt moving on the endless track, the first roller, and the active light of the endless belt are irradiated Cooling the second roller contacting the inner part of the part, cooling the base material layer of the endless belt moving on an endless track and being irradiated with actinic rays on its outer surface; including.

  According to the present invention, it is possible to manufacture an intermediate transfer belt while suppressing the crystallinity of the base material layer from being changed by the heat supplied by irradiation with actinic rays. Further, by using this intermediate transfer belt, a good transfer rate can be realized in an electrophotographic image forming apparatus.

1A and 1B are schematic views showing an example of a manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a flowchart showing an example of an operation procedure of the manufacturing apparatus according to the embodiment of the present invention.

(Configuration of manufacturing equipment)
1A and 1B are schematic diagrams illustrating an example of an intermediate transfer belt manufacturing apparatus 100 according to an embodiment of the present invention. FIG. 1A is a schematic side view of the manufacturing apparatus 100, and FIG. 1B is a schematic plan view of the manufacturing apparatus 100 excluding the actinic ray irradiation apparatus 130 and the purge apparatus 160. The manufacturing apparatus 100 according to the present embodiment is an endless intermediate transfer belt manufacturing apparatus having a base layer made of crystalline resin and a surface layer made of photocurable resin. The manufacturing apparatus 100 includes two or more first rollers 110, a rotation driving device 120, an actinic ray irradiation device 130, a second roller 140, and a cooling device 150. Moreover, the manufacturing apparatus 100 may include other apparatuses such as a purge apparatus 160 and a coating apparatus as necessary. The manufacturing apparatus 100 according to the present embodiment further includes a nitrogen purge apparatus 160.

  The two or more first rollers 110 pivotally support an endless belt 10 having a base material layer and a coating film of a photocurable surface layer coating material disposed on the outer peripheral surface of the base material layer. At least one of the two or more first rollers 110 is connected to the rotation driving device 120 and is driven to rotate. The number of the first rollers 110 is two or more. In the present embodiment, the number of the first rollers 110 is two, and the two first rollers 110 are connected to the rotation driving device 120, respectively.

  If the outer diameter of the first roller 110 is too small, the bending rate of the portion of the endless belt 10 on the first roller 110 becomes high during the production of the intermediate transfer belt, which tends to cause creep. On the other hand, when the outer diameter of the first roller 110 is too large, it becomes difficult to control the temperature of the second roller 140, and the flexibility of the endless belt 10 tends to increase. From such a viewpoint, the outer diameter of the first roller 110 is preferably 60 to 120 mm, for example. Also, the outer diameter of the first roller 110 is 1 on the outer peripheral surface of the first roller 110 that is rotationally driven when forming the surface layer from the viewpoint of suppressing the decrease in flexibility and the occurrence of creep in the intermediate transfer belt. It is preferred that the point be equal to or longer than the distance traveled per second. The outer diameter of each first roller 110 may be the same or different. In the present embodiment, the outer diameters of the two first rollers 110 are the same.

  The rotation driving device 120 transmits power to at least one of the first rollers 110 to rotate and drive at least one of the first rollers 110. Thereby, the manufacturing apparatus 100 which concerns on this Embodiment can move the endless belt 10 pivotally supported by the 1st roller 110 on an endless track. The rotary drive device 120 is composed of components such as a motor, a gear, and a power transmission belt. In the present embodiment, components such as a motor and a gear (not shown) are connected to the two first rollers 110 via the power transmission belt 121, respectively.

  The actinic ray irradiation device 130 emits actinic rays for photopolymerizing the photopolymerizable monomer contained in the coating film of the photocurable surface layer coating material. The actinic ray irradiation device 130 is disposed at a position (outside of the endless belt 10) where the actinic ray is applied to the coating film of the endless belt that is pivotally supported by the first roller 110. The actinic ray irradiation device 130 irradiates actinic rays over the entire width direction of the endless belt 10. Actinic rays are electromagnetic waves that photocure the coating film, and are, for example, ultraviolet rays, electron beams, or γ rays. The actinic ray is preferably ultraviolet rays or electron beams, and more preferably ultraviolet rays from the viewpoint of easy handling and high energy easily obtained.

  Examples of types of actinic light sources include low-pressure mercury lamps, medium-pressure mercury lamps, ultrahigh-pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps, flash (pulse) xenon, and UV-LEDs. From the viewpoint of suppressing the heat supplied to the base material layer and suppressing the lowering of the flexibility in the intermediate transfer belt and the occurrence of creep, the actinic ray irradiation device 130 performs UV-LED irradiation including a UV-LED as a light source. An apparatus is preferred.

  The 2nd roller 140 is cooled by the below-mentioned cooling device 150, and cools the base material layer of endless belt 10 which contacts so that the heat supplied by irradiation of actinic light may be removed. The second roller 140 is a position facing the actinic light irradiation device 130 and a position (endless belt) that abuts the endless belt 10 supported by the first roller 110 from the side opposite to the actinic light irradiation device 130. 10 inside). The arrangement of the second roller 140 can be appropriately set according to the irradiation position of the active light on the endless belt 10, the cooling temperature of the cooling device 150, and the like. For example, the second roller 140 is disposed so as to extend over the entire width direction of the endless belt 10. Further, the second roller 140 is disposed at a position corresponding to a portion of the endless belt 10 to which the actinic ray is irradiated in the rotation direction of the endless belt 10. If the 2nd roller 140 can exhibit said function, for example, a part of a plurality of 2nd rollers 140 will be endless belt 10 from the position corresponding to the portion to which actinic rays of an endless belt are irradiated. It may be arranged on the downstream side in the rotation direction.

  The number and outer diameter of the second rollers 140 can be appropriately changed according to the outer diameter of the first roller 110, the size of the active light irradiation region, and the like. For example, when the outer diameter of the first roller 110 is 60 to 120 mm, the outer diameter of the second roller 140 is preferably 15 to 30 mm. From the viewpoint of suppressing lowering of flexibility and occurrence of creep in the intermediate transfer belt, the outer diameter of the second roller 140 / the outer diameter of the first roller 110 is preferably 1/4. Similarly to the first roller 110, the second roller 140 is connected to a rotation driving device (not shown) and is driven to rotate.

  Cooling the base material layer via the second roller 140 can suppress deterioration due to damage to the base material layer, for example, as compared to cooling the base material layer by bringing a cooling plate into contact therewith. From the viewpoint, it is preferable.

  The cooling device 150 cools the first roller 110 to cool the base material layer in contact with the first roller 110, and cools the second roller 140 to cool the base material layer in contact with the second roller 140. Cooling. The cooling device 150 is built in at least one of the first rollers 110 and at least one of the second rollers 140, respectively. From the viewpoint of effectively cooling the base material layer, the cooling device 150 is preferably incorporated in all of the first rollers 110 and all of the second rollers 140, respectively. The cooling device 150 cools the base material layer through the first roller 110 and the second roller 140 so as to remove the heat supplied to the base material layer by irradiating the endless belt 10 with actinic rays.

  The cooling mechanism of the cooling device 150 can be appropriately designed according to the desired cooling capacity. For example, the cooling device 150 may circulate a temperature-controlled refrigerant inside the first roller 110 and the second roller 140. The cooling device 150 includes a refrigerant, a pump for circulating the refrigerant, a control device for adjusting the flow rate and temperature of the refrigerant, and the like. Examples of the refrigerant include air, water, ethylene glycol, and the like.

  The cooling conditions such as the cooling temperature of the first roller 110 and the cooling temperature of the second roller 140 by the cooling device 150 can be appropriately set within a range in which the object of the present embodiment can be achieved. For example, the cooling condition of the cooling device 150 can be appropriately set according to the irradiation condition of the active light, the thickness of the base material layer, the type of the crystalline resin constituting the base material layer, and the like.

  The crystallinity of the crystalline resin starts to change even at a temperature lower than the glass transition temperature Tg. In addition, the crystallinity of the crystalline resin changes depending on the temperature change of the base material layer. For this reason, it is preferable to cool the 1st roller 110 and the 2nd roller 140 so that the temperature of a base material layer may be lower than the glass transition temperature of crystalline resin, and may be kept constant.

  The purge device 160 adjusts the oxygen concentration by supplying an inert gas such as nitrogen gas or a rare gas to the atmosphere on the endless belt 10. In the present embodiment, the purge device 160 supplies nitrogen gas. In the present embodiment, the purge device 160 is disposed adjacent to the actinic ray irradiation device 130.

  The coating device applies a paint (for example, a surface layer paint) onto the endless belt 10. The coating device can be appropriately selected from known coating devices according to coating conditions such as the thickness of the coating film and the coating method. Examples of the coating device include a spray device.

(Operation procedure of manufacturing equipment)
Next, an operation procedure of the manufacturing apparatus 100 according to this embodiment (an intermediate transfer belt manufacturing method according to this embodiment) will be described. FIG. 2 is a flowchart illustrating an example of an operation procedure of the manufacturing apparatus 100.

1) Step S10
First, the endless belt 10 including the base material layer is installed on the first roller 110 (step S10).

  Specifically, an endless belt 10 including a base material layer is prepared, and the prepared endless belt 10 is pivotally supported on the first roller 110.

  For example, the endless belt 10 including the base material layer may be formed by dissolving a resin composition containing a crystalline resin in a known solvent and drying, or heating the resin composition containing a crystalline resin, They may be kneaded and formed by a molding method such as an extrusion molding method or an inflation molding method.

  Examples of the crystalline resin contained in the base material layer include polycarbonate, polyphenylene sulfide, polyvinylidene fluoride, polyalkylene terephthalate such as polyethylene terephthalate and polybutylene terephthalate, polyether, polyether ketone, polyarylate, polysulfone, and polyether. Sulphone, polyetherimide, polyimide, polyamideimide and polyetheretherketone are included. The kind of these crystalline resins constituting the base material layer may be one kind or more. Among these, polyphenylene sulfide is preferable from the viewpoint of cost reduction.

  The glass transition temperature Tg of the base material layer is preferably 90 ° C. or higher, and more preferably 180 ° C. or higher, from the viewpoint of suppressing lowering of flexibility and occurrence of creep in the intermediate transfer belt.

  The resin composition may further contain a component other than the crystalline resin as necessary. Examples of components other than the crystalline resin include conductive fillers, lubricants, and stabilizers.

  Examples of the conductive filler include carbon black. Carbon black is, for example, neutral carbon black. The addition amount of the conductive filler is preferably 10 to 20 parts by mass, and more preferably 10 to 16 parts by mass with respect to 100 parts by mass of the crystalline resin.

  Examples of lubricants include aliphatic hydrocarbons such as paraffin wax and polyolefin wax; higher fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid; sodium salts, lithium salts, calcium salts of the higher fatty acids, etc. Of higher fatty acid metal salts. These lubricants may be of one type or more. The content of the lubricant is preferably 0.1 to 0.5 parts by mass, more preferably 0.1 to 0.3 parts by mass with respect to 100% by mass of the crystalline resin.

  Examples of stabilizers include phenolic antioxidants, amine antioxidants, hydroquinone antioxidants, sulfur antioxidants and phosphoric acid antioxidants. These stabilizers may be of one type or more. The content of the stabilizer is preferably 2 to 10 parts by mass and more preferably 2 to 5 parts by mass with respect to 100% by mass of the crystalline resin.

2) Step S20
Next, two or more first rollers 110 supporting the endless belt 10 having the base material layer and the coating film of the photocurable coating material for the surface layer disposed on the outer peripheral surface of the base material layer are provided. The endless belt 10 is moved on the endless track by being rotationally driven (step S20).

  Specifically, first, a coating material for a surface layer containing a photopolymerizable monomer is prepared. Next, the prepared coating material for the surface layer is applied on the outer peripheral surface of the endless belt 10 that is pivotally supported by the first roller 110 to form a coating film for the coating material for the surface layer. Finally, the first roller 110 is rotationally driven by the rotation driving device 120 to move the endless belt 10 on the endless track.

  The coating material for the surface layer can be prepared, for example, by adding a photopolymerizable monomer that is a precursor of a photocurable resin constituting the surface layer and a photopolymerization initiator to a known solvent. Surface layer coatings are light stabilizers, UV absorbers, catalysts, colorants, antistatic agents, lubricants, leveling agents, antifoaming agents, polymerization accelerators, antioxidants, flame retardants, and infrared absorbers as necessary. It may further contain other components such as an agent, a surfactant and a surface modifier.

  Examples of the photopolymerizable monomer include styrene monomers, acrylic monomers, methacrylic monomers, vinyl toluene monomers, vinyl acetate monomers, and N-vinyl pyrrolidone monomers. These polymerizable monomers may be of one kind or more.

Since the photopolymerizable monomer can be polymerized in a small amount of light or in a short time, a reactive group of an acryloyl group (CH ₂ ═CHCO—) or a methacryloyl group (CH ₂ ═C (CH ₃ ) CO—) is added. It is preferable that it is a compound which has. The photopolymerizable monomer is preferably an acrylic monomer having two or more of these reactive groups. Furthermore, it is preferably an oligomer of a photopolymerizable monomer.

  Examples of the photopolymerizable monomer having an acryloyl group or a methacryloyl group include the following formula No. The compound shown by 1-21 is included.

  Examples of the photopolymerization initiator include benzophenone, Michler ketone, 1-hydroxycyclohexyl-phenyl ketone, thioxanthone, benzobutyl ether, acyloxime ester, dibenzothroben and bisacylphosphine oxide.

  The addition amount of the photopolymerization initiator is preferably 0.1 to 30 parts by mass, and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the photopolymerizable monomer.

  Examples of the solvent used for the coating material for the surface layer include n-butyl alcohol, isopropyl alcohol, ethyl alcohol, methyl alcohol, methyl isobutyl ketone and methyl ethyl ketone.

  The method for applying the surface layer coating material can be appropriately selected from known methods according to the thickness of the coating film, the composition of the surface layer coating material, and the like. For example, the coating material for the surface layer may be spray applied onto the endless belt 10 using a known spray coating device.

  The coating film is preferably formed such that the thickness after photocuring (the thickness of the surface layer) is 2.0 to 5.0 μm. If the thickness of the surface layer is too thin, the mechanical strength may be insufficient, and the filler contained in the surface layer may be insufficient, resulting in a decrease in transfer rate. If the surface layer is too thick, the flexibility of the intermediate transfer belt may be reduced. The thickness of the surface layer can be measured by a known method, and can be adjusted by the coating method and the number of coatings for the surface layer described later. The thickness of the surface layer can be obtained, for example, as a measured value obtained from a cross section when the intermediate transfer belt is cut in the stacking direction or an average value thereof.

  The rotation speed and the number of rotations of the first roller 110 can be appropriately adjusted according to the outer diameter of the first roller 110, the irradiation condition of actinic rays, the cooling condition of the base material layer, and the like. From the viewpoint of suppressing the decrease in the flexibility of the intermediate transfer belt and the occurrence of creep and realizing the desired transferability in the image forming apparatus, the distance that one point on the outer peripheral surface of the first roller 110 travels per second is It is preferable to rotate the first roller 110 so as to be the same as or shorter than the outer diameter of the first roller 110.

  In addition, the number of turns for moving the endless belt 10 on the endless track is at least two. By moving the endless belt 10 at least two times on the endless track, the amount of heat supplied to the endless belt 10 by irradiation with actinic rays can be adjusted in step S30 described later.

3) Step S30
Next, actinic rays are applied to the coating film of the endless belt 10 moving on the endless track (step S30).

  The coating film is irradiated with actinic rays in order to photopolymerize the photopolymerizable monomer and form a surface layer. At this time, by irradiating the coating film with actinic rays while rotating the endless belt 10, the temperature rise of the base material layer is suppressed, and the change in crystallinity of the base material layer is suppressed, while the photopolymerizable monomer. Can be photopolymerized. The irradiation energy, the number of irradiations, the irradiation time, etc. of the actinic ray can be appropriately set according to the output of the light source, the type of the photopolymerizable monomer, and the like.

Irradiation light amount of the active ray curing unevenness of the coating film hardness, curing time, from the viewpoint of curing speed, it is preferably 100 mJ / cm ² or more, more preferably 120~200mJ / cm ² 150 to 180 mJ / cm ² is more preferable. The amount of irradiation light can be measured by, for example, UIT250 (made by USHIO INC.). As described above, from the viewpoint of reducing the heat supplied to the base material layer, the coating film is preferably irradiated with ultraviolet rays from a UV-LED light source device.

  The irradiation time of the actinic ray is preferably 0.5 seconds to 5 minutes, and more preferably 3 seconds to 2 minutes from the viewpoint of the curing efficiency and work efficiency of the coating film.

  The oxygen concentration in the atmosphere when irradiating the coating film with actinic rays is preferably 5% or less, and preferably 1% or less, from the viewpoint of curing unevenness and curing time (curing efficiency) of the coating film. It is more preferable. The oxygen concentration can be adjusted, for example, by introducing nitrogen gas into the atmosphere by the purge device 160. The oxygen concentration can be measured by, for example, an atmospheric gas management oxygen concentration meter “OX100” (manufactured by Yokogawa Electric Corporation).

4) Step S40
Next, by cooling the first roller 110 and the second roller 140 that abuts the inner portion of the endless belt 10 where the actinic ray is irradiated, the first roller 110 moves on the endless track, and on the outer surface. The base material layer of the endless belt 10 irradiated with the active light is cooled (step S40).

  While irradiating the outer surface of the endless belt 10 with actinic rays and cooling the first roller 110 and the second roller 140, the base material layer in contact with the first roller 110 and the second roller 140 is cooled. By removing the heat supplied to the base material layer by irradiation with actinic rays, it is possible to suppress a change in crystallinity of the crystalline resin constituting the base material layer. As a result, it is possible to form the surface layer while suppressing the decrease in flexibility and the occurrence of creep in the intermediate transfer belt.

  At this time, from the viewpoint of realizing good bendability, creep properties, and transferability, the first roller 110 and the second roller have an outer diameter of the second roller 140 / an outer diameter of the first roller 110 of 1/4. It is preferable to cool 140 and cool the base material layer of the endless belt 10.

  The cooling conditions such as the cooling temperature of the first roller 110 and the cooling temperature of the second roller 140 can be appropriately set within a range in which the object of the present embodiment can be achieved. For example, the cooling temperature of the first roller 110 and the second roller 140 can be appropriately set according to the irradiation conditions of the actinic rays, the thickness of the base material layer, the type of crystalline resin constituting the base material layer, and the like.

  As described above, the crystallinity of the crystalline resin starts to change even at a temperature lower than the glass transition temperature Tg. In addition, the crystallinity of the crystalline resin changes depending on the temperature change of the base material layer. For this reason, it is preferable to cool the 1st roller 110 and the 2nd roller 140 so that the temperature of a base material layer may be lower than the glass transition temperature of crystalline resin, and may be kept constant. For example, when polyphenylene sulfide (Tg: 90 ° C.) is used as the crystalline resin, the substrate layer may be cooled to about 40 ° C.

  In addition, the second roller 140 is preferably cooled at a lower temperature than the first roller 110. Compared with the part on the 1st roller 110 of a base material layer, since the heat by irradiation of actinic light is supplied more to the part on the 2nd roller 140 of a base material layer, the 2nd roller 140 is more By cooling at a low temperature, the heat supplied to the base material layer by actinic rays can be efficiently removed, and the temperature of the base material layer can be kept constant.

  As is clear from the above description, the intermediate transfer belt manufacturing apparatus according to the present embodiment is an endless intermediate transfer belt having a base layer made of crystalline resin and a surface layer made of photocurable resin. Two or more manufacturing apparatuses for supporting an endless belt having the base material layer and a coating film of a photocurable coating material for the surface layer disposed on the outer peripheral surface of the base material layer. A first roller, a rotational drive device for rotationally driving at least one of the first rollers, and a position for irradiating the coating film of the endless belt supported by the first roller with actinic rays The actinic ray irradiating device and the position facing the actinic ray irradiating device, the position abutting on the endless belt pivotally supported by the first roller from the side opposite to the actinic ray irradiating device A second roller disposed on the 1 are built respectively and the second roller with the roller, having a cooling device for cooling the substrate layer. Accordingly, the intermediate transfer belt can be manufactured while suppressing the crystallinity of the base material layer from being changed by the heat supplied by the irradiation of the actinic ray. Further, by using this intermediate transfer belt, a good transfer rate can be realized in an electrophotographic image forming apparatus.

  The actinic ray irradiation device is a UV-LED irradiation device for irradiating ultraviolet light as actinic rays, suppressing heat supplied to the base material layer, lowering the flexibility of the intermediate transfer belt and generating creep. From the viewpoint of suppressing the above, it is more effective.

  The fact that the outer diameter of the second roller / the outer diameter of the first roller is 1/4 is even more effective from the viewpoint of realizing better bendability, creep properties, and transferability.

  When the outer diameter of the first roller is rotationally driven, one point on the outer peripheral surface of the first roller is equal to or longer than the distance traveled per second, which means that better flexibility, creep properties and This is even more effective from the viewpoint of realizing transferability.

  The outer diameter of the first roller is 60 to 120 mm and the outer diameter of the second roller is 15 to 30 mm, which is more effective from the viewpoint of suppressing the occurrence of creep in the intermediate transfer belt. .

  Further, the method for producing an intermediate transfer belt according to the present embodiment is a method for producing an endless intermediate transfer belt having a base layer made of crystalline resin and a surface layer made of photocurable resin, Two or more first rollers that pivotally support an endless belt having a base material layer and a coating film of a photocurable surface layer paint disposed on the outer peripheral surface of the base material layer are rotationally driven, The step of moving the endless belt on an endless track, the step of irradiating the coating film of the endless belt moving on the endless track, the first roller, and the active light of the endless belt The second roller that contacts the inner part of the irradiated part is cooled to cool the base material layer of the endless belt that moves on the endless track and is irradiated with actinic rays on the outer surface. And a step of performing. Accordingly, the intermediate transfer belt can be manufactured while suppressing the crystallinity of the base material layer from being changed by the heat supplied by the irradiation of the actinic ray. Further, by using this intermediate transfer belt, a good transfer rate can be realized in an electrophotographic image forming apparatus.

  In the step of irradiating the coating film with actinic rays, irradiating with ultraviolet light from a UV-LED irradiator suppresses heat supplied to the base material layer, thereby lowering flexibility and creeping in the intermediate transfer belt. From the viewpoint of suppressing the occurrence of the above, it is more effective.

  In the step of cooling the base material layer, the outer diameter of the second roller / the outer diameter of the first roller is 1/4, and it is better to cool the first roller and the second roller. From the viewpoint of realizing flexibility, creep property, and transfer property, it is more effective.

  In the step of moving the endless belt on the endless track, the distance traveled by one point on the outer peripheral surface of the first roller that is rotationally driven per second is equal to the outer diameter of the first roller, or Driving the first roller so as to be shorter is more effective from the viewpoint of realizing better bending properties, creep properties, and transfer properties.

  From the viewpoint of realizing better mechanical strength and transfer rate, further including the step of forming the coating film so that the thickness after photocuring of the coating film is 2.0 to 5.0 μm, Even more effective.

  In addition, the method for producing an intermediate transfer belt according to the present invention may include a step of drying the coating film as necessary. In step S20, the coating film may be dried after forming the coating film for the surface layer coating, or in step S40, the coating film may be dried after the photopolymerization reaction. The method for drying the coating film can be appropriately selected according to the type of solvent and the desired thickness of the surface layer. Examples of the method for drying the coating film include natural drying and heat drying.

  The present invention will be described more specifically with reference to the following examples and comparative examples. In addition, this invention is not limited to a following example.

1. Preparation of intermediate transfer belt [Intermediate transfer belt 1]
(1) Formation of base material layer First, using a kneading twin screw extruder (PMT32-III: manufactured by IKG Corporation), the following amounts of each component were kneaded to prepare pellets of a crystalline resin composition. . At this time, the crystalline resin was dried at 130 ° C. for 8 hours and cooled to about 60 ° C. and used for kneading.
Polyphenylene sulfide 100 parts by mass Phenolic antioxidant 5 parts by mass Acetylene black 16 parts by mass Calcium montanate 0.2 parts by mass

  As the crystalline resin, polyphenylene sulfide (E2180: manufactured by Toray Industries, Inc.) having a melting point of 280 ° C. and Tg of 90 ° C. is used. ”Is a registered trademark of the company, acetylene black (DENKA BLACK HS-100: manufactured by DENKA CORPORATION,“ DENKA BLACK ”is a registered trademark of the company) is used as the conductive filler, and Montan is used as the lubricant. Calcium acid (Seridust 5551: manufactured by Clariant Japan, “Seridust” is a registered trademark) was used.

  Next, the produced pellets were dried at 130 ° C. for 8 hours. Using a 40 mm diameter extruder equipped with a mandrel with an outer diameter of 140 mm on a shaft of a six-spiral spiral annular die having a diameter of 150 mm and a lip width of 1 mm, the dried pellets in a molten tube state Extruded. The extruded melt tube was brought into contact with the outer surface of the mandrel cooled to 60 ° C. and cooled and solidified to produce an endless belt. Next, the endless belt was held in a cylindrical shape by a core installed in the endless belt and a roll installed on the outside, and was cut into a ring with a length exceeding 290 mm. From the above, an endless belt including the base material layer was manufactured.

(2) Formation of surface layer Next, the following components were dissolved and dispersed in propylene glycol monomethyl ether acetate (PMA) in the following amounts so that the solid content concentration would be 10% by mass. A paint was prepared.
Dipentaerythritol hexaacrylate (DPHA) 85 parts by weight Polymerizable polymer compound 10 parts by weight Tin oxide 5 parts by weight

  DPHA (manufactured by Nippon Kayaku Co., Ltd.), which is a polyfunctional (meth) acrylate, is used as the photopolymerizable monomer, and a polymerizable polymer compound having a low surface energy group (Megafac) is used as the polymerizable polymer compound. : DIC Corporation, “Megafuck” is a registered trademark of the company, and tin oxide (CIK Nanotech Co., Ltd.) was used as the metal oxide particles.

Next, two first rollers having an outer diameter of 120 mm, a rotation driving device for rotating and driving the two first rollers, a UV-LED irradiation device, and three second rollers having an outer diameter of 30 mm, An endless belt including a base material layer was pivotally supported on a first roller of an intermediate transfer belt manufacturing apparatus having cooling devices built in two first rollers and three second rollers. Next, using a spray device (manufactured by WIDY Mechatronic Solutions Co., Ltd.), the surface layer paint is spray-applied from the nozzle onto the outer surface of the endless belt under the following application conditions to form a coating film of the surface layer paint. Formed.
Nozzle scan speed: 1 to 10 mm / sec. Distance between endless belt and nozzle: 100 to 150 mm
Number of nozzles: 1
Supply amount of paint: 1 to 5 mL / min Flow rate of O ₂ : ₂ to 6 L / min

Next, the first roller was driven to rotate at a rotational speed of 60 mm / second, and the endless belt was moved on the endless track. Subsequently, the UV-LED irradiation device irradiated ultraviolet light onto the coating film of the surface layer coating material under the following irradiation conditions. At this time, the base material layer was cooled so that the temperature of the base material layer did not exceed 40 ° C. by cooling the first roller and the second roller.
Type of light source: UV-LED lamp (UV-SPX series: manufactured by Rebox Co., Ltd.)
Distance between endless belt and UV-LED irradiation device: 40 mm
Ultraviolet light wavelength: 365 nm
Irradiation time of ultraviolet light: 150 seconds Irradiation light amount of ultraviolet light on the endless belt surface: 100 mW / cm ²
Endless belt laps: 3 laps

  The intermediate transfer belt 1 was produced by the above procedure. The thickness of the surface layer of the intermediate transfer belt 1 after photocuring was 3 μm.

[Intermediate transfer belt 2]
Same as the intermediate transfer belt 1 except that the outer diameter of the first roller is 80 mm, the outer diameter of the second roller is 20 mm, the number of laps of the endless belt is 2, and the thickness of the surface layer is 2 μm. Thus, an intermediate transfer belt 2 was produced.

[Intermediate transfer belt 3]
An intermediate transfer belt 3 was produced in the same manner as the intermediate transfer belt 2 except that the number of times of the endless belt was 4 and the thickness of the surface layer was 4 μm.

[Intermediate transfer belt 4]
An intermediate transfer belt 4 was produced in the same manner as the intermediate transfer belt 2 except that polyether ether ketone (PEEK, manufactured by Victrex) having a melting point of 343 ° C. and a Tg of 145 ° C. was used as the crystalline resin.

[Intermediate transfer belt 5]
An intermediate transfer belt 5 was produced in the same manner as the intermediate transfer belt 1 except that the outer diameter of the first roller was 60 mm and the outer diameter of the second roller was 15 mm.

[Intermediate transfer belt 6]
An intermediate transfer belt 6 was produced in the same manner as the intermediate transfer belt 5 except that the number of times of the endless belt was 4 and the thickness of the surface layer was 4 μm.

[Intermediate transfer belt 7]
An intermediate transfer belt 7 was produced in the same manner as the intermediate transfer belt 6 except that the outer diameter of the second roller was 10 mm.

[Intermediate transfer belt 8]
An intermediate transfer belt 8 was produced in the same manner as the intermediate transfer belt 1 except that the outer diameter of the first roller was 40 mm and the outer diameter of the second roller was 15 mm.

[Intermediate transfer belt 9]
An intermediate transfer belt 9 was produced in the same manner as the intermediate transfer belt 5 except that a manufacturing apparatus having no second roller was used and the number of times of the endless belt was changed to two.

[Intermediate transfer belt 10]
The intermediate transfer belt 1 except that a manufacturing apparatus having a belt feeding machine and a winder instead of the first roller, that is, a one-pass manufacturing apparatus is used and the outer diameter of the second roller is 20 mm. Similarly, an intermediate transfer belt 10 was produced.

2. Evaluation (1) Flexibility The intermediate transfer belt bendability was evaluated based on the following evaluation criteria by measuring the number of folding times by a measuring method based on JIS P-8115 (folding resistance test). For the intermediate transfer belts 1 to 10, the number of folding times was measured three times, and the average value was calculated. From the standpoint of enduring actual use, it was judged as acceptable if the folding resistance was 15,000 times or more.
(Evaluation criteria)
A: Folding number of times is 20,000 times or more. ○: Folding number of times is 15,000 times or more and less than 20,000 times. Δ: Folding number of times is 10,000 times or more and less than 15,000 times. Less than 10,000 times

(2) Creepability For the intermediate transfer belts 1 to 10, test pieces cut into a size of 50 mm in width and 130 mm in length were prepared. Subsequently, the dimension a of the length direction of each test piece in the initial state was measured. Next, the test piece was put in an aluminum pipe having an inner diameter of 28 mm, and the pipe was left in an environment of 40 ° C. and 95% rh for 100 hours. The pipe was then left for 12 hours in an environment of 23 ° C. and 50% rh. Finally, the test piece was taken out from the pipe, the dimension b in the length direction of the test piece was immediately measured, and the creep rate was calculated by the following equation (1).
Creep rate (%) = (ab) / (ax) × 100 (1)
[In the above formula (1), X represents the size of the overlapping portion of the test pieces in the pipe. In this evaluation, since a pipe having an inner diameter of 28 mm is used, X is 42.0 mm (130-28π). ]

For example, when the dimension b in the length direction of the test piece returns to the original dimension a in the length direction immediately after the test piece is taken out from the pipe, the creep rate becomes 0 because b = a. On the other hand, when the test piece keeps the shape in the pipe immediately after taking out the test piece from the pipe, b = −X, and the creep rate becomes 100%. For the intermediate transfer belts 1 to 10, the creep rate was calculated and evaluated according to the following evaluation criteria. From the viewpoint of suppressing unevenness in image density, it was determined that the creep rate was less than 75%.
(Evaluation criteria)
◎: Creep rate is less than 40% ○: Creep rate is 40% or more and less than 75% △: Creep rate is 75% or more and less than 80% ×: Creep rate is 80% or more

(3) Transferability A color printer (MAGICCOLOR 2400, exposure recording density 600 × 1200 dpi) manufactured by Konica Minolta Co., Ltd. is mounted with intermediate transfer belts 1 to 10, respectively, and wet polymerization toner having a volume median diameter (D ₅₀ ) of 6.5 μm is used. Then, a printing test of 50,000 sheets was conducted. When a solid image in which two colors of yellow (Y) and cyan (C) are overlaid is printed after the printing test, the image is transferred onto the recording paper after the secondary transfer with respect to the toner mass on the intermediate transfer belt before the secondary transfer. The mass ratio (transfer rate) of the toner thus obtained was calculated.

Specifically, using a suction device, a toner having a predetermined area (3 points of 10 mm × 50 mm) on the intermediate transfer belt after the primary transfer and before the secondary transfer is collected and subjected to the secondary transfer. The previous toner mass A was measured. Next, the transfer residual toner on the intermediate transfer belt after the secondary transfer was collected with a booker tape and attached to a white paper. Next, using a spectrocolorimeter (CM-2002: manufactured by Konica Minolta Sensing Co., Ltd.), the color of the white paper to which the transfer residual toner was attached was measured. Based on the color measurement result and a calibration curve prepared in advance, the mass B of the transfer residual toner was measured. Finally, the transfer rate was calculated by the following equation (2).
Transfer rate (%) = (1−B / A) × 100 (2)

For the intermediate transfer belts 1 to 10, the transfer rate was calculated and evaluated according to the following evaluation criteria. From the standpoint of enduring actual use, if the transfer rate was 95% or more, it was judged as acceptable.
(Evaluation criteria)
○: Transfer rate is 95% or more Δ: Transfer rate is 85% or more and less than 95% ×: Transfer rate is less than 85%

  Classification, intermediate transfer belt No. The outer diameter (A) of the first roller, the outer diameter (B) of the second roller, the value of B / A, the rotational speed, the number of revolutions of the endless belt, the type of light source, the crystalline resin, the thickness of the surface layer, and The evaluation results are shown in Table 1. In Table 1, “PPS” of the crystalline resin means polyphenylene sulfide, and “PEEK” means polyetheretherketone.

  As is clear from Table 1, all of the intermediate transfer belt belts 1 to 8 showed sufficient performance in all of flexibility, creep property and transfer property. This is because when the surface layer is formed, the first roller and the second roller are cooled to move on the endless track, and the base layer of the endless belt whose outer surface is irradiated with actinic rays is cooled. It is thought that it is because.

  Moreover, in the intermediate transfer belts 1 to 6, all of the intermediate transfer belts 1 to 6 showed better performance with respect to flexibility, creep property, or both. This is because the outer diameter of the first roller is equal to or longer than the distance traveled by one point on the outer peripheral surface of the first roller being driven to rotate per second, and the outer diameter / first of the second roller. This is considered because the outer diameter (B / A) of the roller is 1/4.

  On the other hand, in the intermediate transfer belt belts 9 and 10, all of the flexibility, the creep property, and the transfer property were insufficient. This is because the intermediate transfer belt 9 moves on an endless track when the surface layer is formed, and the inner surface of the endless belt where the actinic ray is irradiated on the outer surface of the intermediate transfer belt 9. This is probably because the part was not cooled. Regarding the intermediate transfer belt 10, it is considered that when the surface layer is formed, the portion of the base material layer on the roller that supports the endless belt is not cooled.

  According to the present invention, further improvement in performance of an electrophotographic image forming apparatus is expected, and further spread of the image forming apparatus is expected.

DESCRIPTION OF SYMBOLS 10 Endless belt 100 Manufacturing apparatus 110 1st roller 120 Rotation drive apparatus 121 Power transmission belt 130 Actinic ray irradiation apparatus 140 2nd roller 150 Cooling apparatus 160 Purge apparatus

Claims (10)

An apparatus for producing an endless intermediate transfer belt having a base layer made of crystalline resin and a surface layer made of photocurable resin,
Two or more first rollers for pivotally supporting an endless belt having the base material layer and a coating film of a photocurable surface layer paint disposed on the outer peripheral surface of the base material layer;
A rotational drive device for rotationally driving at least one of the first rollers;
An actinic ray irradiation device disposed at a position where the actinic ray is applied to the coating film of the endless belt that is pivotally supported by the first roller;
A second roller disposed at a position facing the actinic ray irradiation device and in contact with the endless belt pivotally supported by the first roller from a side opposite to the actinic ray irradiation device;
Built in each of the first roller and the second roller, a cooling device for cooling the base material layer,
An intermediate transfer belt manufacturing apparatus.   The intermediate transfer belt manufacturing apparatus according to claim 1, wherein the actinic light irradiation device is a UV-LED irradiation device for irradiating ultraviolet light as active light.   The intermediate transfer belt manufacturing apparatus according to claim 1, wherein an outer diameter of the second roller / an outer diameter of the first roller is ¼.   The outer diameter of the first roller is the same as or longer than the distance traveled by one point on the outer peripheral surface of the first roller being driven to rotate per second. An intermediate transfer belt manufacturing apparatus according to claim 1. The outer diameter of the first roller is 60 to 120 mm,
The outer diameter of the second roller is 15 to 30 mm.
The intermediate transfer belt manufacturing apparatus according to any one of claims 1 to 4. A method for producing an endless intermediate transfer belt having a base layer made of crystalline resin and a surface layer made of photocurable resin,
Two or more first rollers that pivotally support an endless belt having the base material layer and a coating film of a photocurable surface layer paint disposed on the outer peripheral surface of the base material layer are driven to rotate. Moving the endless belt on an endless track;
Irradiating the coating film of the endless belt moving on an endless track with actinic rays;
The first roller and the second roller in contact with the inner portion of the endless belt irradiated with the actinic ray move to cool the first roller and move on an endless track, and the outer surface is irradiated with the actinic ray Cooling the base material layer of the endless belt,
A process for producing an intermediate transfer belt, comprising:   The method for producing an intermediate transfer belt according to claim 6, wherein in the step of irradiating the coating film with actinic rays, ultraviolet light from a UV-LED irradiation device is irradiated.   The step of cooling the base material layer cools the first roller and the second roller, wherein the outer diameter of the second roller / the outer diameter of the first roller is 1/4. A process for producing an intermediate transfer belt as described in 1).   In the step of moving the endless belt on the endless track, the distance traveled by one point on the outer peripheral surface of the first roller per second is equal to or shorter than the outer diameter of the first roller. The method for manufacturing an intermediate transfer belt according to any one of claims 6 to 8, wherein the first roller is rotationally driven. The intermediate transfer belt according to any one of claims 6 to 9, further comprising a step of forming the coating film so that a thickness after photocuring of the coating film is 2.0 to 5.0 µm. Production method.

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