JP4564709B2 - Manufacturing method of non-right cylinder with resin layer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fixing belt of an image heating fixing device.
[0002]
[Prior art]
In the electrophotographic process, a heat roller type apparatus has been widely used as a fixing device that heats and fixes an unfixed image (toner image) formed on a recording sheet as a permanently fixed image. In general, a heat source such as a halogen heater is used in the roller.
[0003]
On the other hand, as a heating method, a method of heating a resin belt or a metal belt having a small heat capacity using a ceramic heater as a heat source has been widely proposed and implemented. That is, generally, a nip portion is formed by sandwiching a heat-resistant belt (fixing belt) between a ceramic heater as a heating element and a pressure roller as a pressure member, and the belt in the nip portion and the pressure roller In between, the recording sheet on which the unfixed toner image to be image-fixed is formed and supported is introduced and conveyed together with the belt, so that the heat of the ceramic heater is applied to the recording sheet through the belt at the nip portion, Further, the unfixed toner image is fixed to the recording sheet by heat and pressure by the pressure applied at the nip portion.
[0004]
This belt heating type fixing device can be configured as an on-demand type device using a low heat capacity member as a belt. That is, it is only necessary to energize a ceramic heater as a heat source to generate heat to a predetermined fixing temperature only when image forming of the image forming apparatus is executed, and wait time from power-on of the image forming apparatus to an image forming executable state Are short (quick start), and power consumption during standby is significantly small (power saving).
[0005]
A heat-resistant resin or the like is used as a belt in such a belt heating method, and a polyimide resin excellent in heat resistance and strength is used as the heat-resistant resin.
However, when the machine is further increased in speed and durability, the resin film has insufficient strength, so a belt having a base layer made of a metal having excellent strength, for example, SUS, nickel, aluminum, copper or the like is used. It has been proposed.
[0006]
In addition, an induction heating method is also disclosed in which a metal belt is used and self-heats by an eddy current due to electromagnetic induction (see, for example, Patent Document 1). There has been proposed a heating device that generates eddy current in a belt itself or a conductive member close to the belt and generates heat by Joule heat. In this electromagnetic induction heating method, the heat generation area can be made closer to the object to be heated, so that the efficiency of energy consumption can be increased.
[0007]
As a method for driving the fixing belt of the belt heating type fixing device, a film pressure-contacted by a film guide for guiding the inner surface of the belt and a pressure roller is driven by a pressure roller rotational drive (pressure roller driving method). On the contrary, there is a type in which a pressure roller is driven to rotate by driving an endless belt stretched between a drive roller and a tension roller.
[0008]
Copiers and laser printers using fixing devices such as those mentioned above have problems with stable paper passing due to demands for higher speed, higher image quality, automatic duplexing, colorization, and power saving. There was a case. As a fixing belt that meets these demands, a metal layer for imparting strength, an elastic layer using silicone rubber or the like for applying sufficient heat to the recording sheet, and a fluororesin having good releasability from toner Multilayer fixing belts having layers have been used. Such fixing belt shapes include a straight type, a reverse crown type, and a normal crown type used for the purpose of countermeasures against paper wrinkles because of the relationship with the facing roller. The crown amount of the crown type varies depending on the type of equipment such as a copying machine or a laser beam printer used.
[0009]
In order to manufacture such a fixing belt having a multi-layer structure having different shapes, an elastic layer such as rubber is vulcanized and bonded to a metal layer, and then polished into a reverse crown shape, for example. Thereafter, a primer was applied, and a fluororesin tube in which a fluororesin serving as the outermost layer was previously formed into a tube was coated on a polished reverse crown belt to obtain a product.
[0010]
However, according to such a conventional manufacturing method, since the elastic layer polishing step is performed after the elastic layer forming step, it takes time to manufacture the fixing belt, which may increase the product cost. . Further, since the thickness of the elastic layer in the axial direction is changed by polishing the elastic layer, the image quality may be uneven.
[0011]
[Patent Document 1]
JP-A-7-114276 [0012]
[Problems to be solved by the invention]
In view of the circumstances as described above, the object of the present invention is to provide a film thickness accuracy that is good, a low resin loss, and a crown-shaped, reverse crown-shaped, or tapered cylinder, and the film thickness is substantially uniform. Is to provide a simple cylinder.
[0013]
[Means for Solving the Problems]
To achieve the above object, the present invention is a thin cylinder that is molded into a non-straight cylindrical shape, and inserting the core of right circular cylindrical shape having a maximum inner diameter or an outer diameter in the axial direction of said thin cylinder, the the thin cylindrical with annular coating device onto the thin cylinder while correcting the straight cylindrical shape to form an uncured resin layer having a uniform thickness, removing the core after the formation of the uncured resin layer, after the non-linear cylindrical shape again the thin cylinder, a method of manufacturing a resin layer with a non-straight cylinder, characterized in that have a step of curing the uncured resin layer.
In the present invention, the term “resin” is used to include rubber.
In the present invention, it is possible to obtain a non-rectilinear cylinder with a resin layer having good film thickness accuracy, little resin loss, and substantially uniform film thickness.
In the above step, it is preferable to perform temporary curing of the uncured resin layer before removing the core.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
In the present invention, a straight cylindrical core is inserted into a thin cylinder formed into a non-cylinder shape, and an uncured resin layer is formed on the thin cylinder with the thin cylinder corrected to a straight cylinder. The present invention relates to a non-cylinder with a resin layer, characterized in that the core is removed after the cured resin is formed, and the thin-walled cylinder is made into a non-cylinder shape again.
[0015]
According to the present invention, the thickness of the resin layer formed on the thin cylindrical surface is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more. Moreover, 5000 micrometers or less are preferable, 2000 micrometers or less are more preferable, and 1000 micrometers or less are still more preferable. The 10μm or more thicknesses forming, uninterrupted ejection unloading of uncured resin of a high viscosity used in the present invention, since the problem of adhering to thin cylindrical surface does not occur, thereby enabling stable film formation. In addition, in the formation of a film thickness of 5000 μm or less, the resin moves to the lower side of the thin cylinder at the time of curing, so that the film thickness does not increase and a uniform film thickness can be formed.
[0016]
In the present invention, the “right cylindrical shape” means that the difference between the maximum value and the minimum value of the cross-sectional diameter in the longitudinal direction is 0.03 mm or less. Further, the “non-right cylindrical shape” refers to a crown shape, an inverted crown shape, a tapered shape, or the like in which the difference between the maximum value and the minimum value of the inner diameter of the cross-sectional diameter in the longitudinal direction exceeds 0.03 mm. Here, the crown shape is a shape in which the central portion in the axial direction is thick and both end portions are narrowed, and the reverse crown shape is a shape in which the central portion in the axial direction is thin and both end portions are thick. “Formation” means applying a resin layer on a thin cylinder.
[0017]
As a method for forming the resin layer applied on the thin cylinder according to the present invention, any coating method such as a dip coating method, a spin coating method, a spray coating method, a ring coating method, and a blade coating method can be adopted.
In the present invention, the non-cylinder-shaped thin cylinder is corrected to a straight-cylindrical shape when the uncured resin layer is formed, so that the film thickness accuracy is good, the resin loss is small, and the film thickness is finally substantially A uniform non-right cylinder can be obtained.
[0018]
The thin cylinder formed into a non-cylindrical shape in the present invention has a cylindrical shape with a film thickness of about 500 μm or less, and is a seamless tube manufactured by electroforming, drawing, deep drawing, cutting, etc. It includes a loop shape, an annular shape, a tubular shape, a ring shape, a tubular shape, an annular shape, a hollow shape, etc. formed by connecting the end portions of the sheet-like film, and the material thereof is either metal or resin These materials may be laminated or compounded. The thin cylinder is formed into a non-cylinder shape by bulging, drawing, ironing, polishing, or the like, or is formed into a non-cylinder shape when the thin cylinder is formed. Moreover, when forming a resin layer in the thin cylinder in this invention, the core inserted in a thin cylinder is a right cylinder shape.
[0019]
In the present invention, the uncured resin is a resin that is liquid at the time of application and assumes a resinous state upon curing. Examples of the uncured resin include thermosetting resins and silicone rubbers, but are not limited to these resins.
In this invention, it is a non-cylinder with a resin layer which forms an uncured resin layer on the surface of a thin cylinder by a ring coat method, and its manufacturing method. By using the ring coating method in this way, the resin layer can be formed in a constant film thickness with little solvent loss along the outer peripheral surface on the thin cylinder without solvent.
[0020]
The present invention provides a non-rectilinear cylinder with a resin layer that cures an uncured resin layer in a state where the core is removed from the thin cylinder and the thin cylinder is corrected to a non-cylindrical cylinder again, and a method for manufacturing the non-cylinder with a resin layer. In this way, the uncured resin layer is cured in a state where the thin-walled cylinder is corrected to the non-rectilinear shape again, whereby deformation of the cured resin layer can be prevented. At this time, the viscosity of the uncured resin is preferably 1 Pa · s or more, more preferably 5 Pa · s or more, and further preferably 10 Pa · s or more. Moreover, 2000 Pa * s or less is preferable, 1500 Pa * s or less is more preferable, and 500 Pa * s or less is still more preferable. Here, the viscosity was measured at 25 ° C. by a BH rotational viscometer method.
[0021]
In this invention, it is a non-right cylinder with a resin layer whose thin cylinder is a metal, and its manufacturing method. Thus, the intensity | strength of the non-cylinder with a resin layer can be improved by using a thin cylinder as a metal.
Furthermore, in this invention, it is a non-right cylinder with a resin layer whose thin-walled cylinder is a nickel electroformed cylinder, and its manufacturing method. Thus, by making the thin cylinder into a nickel electroformed cylinder, the cylindrical surface can be smoothed and the film thickness of the resin layer raw material can be made uniform.
[0022]
In this invention, it is a non-right cylinder with a resin layer which uses the resin layer after hardening | curing uncured resin as an elastic layer, and its manufacturing method. Thus, by using the resin layer after curing of the uncured resin as an elastic layer, low compressibility and low compression set can be imparted to the non-cylinder with resin layer.
In this invention, it is a non-right cylinder with a resin layer which used the silicone rubber layer as an elastic layer, and its manufacturing method. Thus, by using a silicone rubber layer as an elastic layer, high heat resistance, low compressibility, and low compression set can be imparted to a non-right cylinder with a resin layer. As the resin layer, addition type silicone rubber is more preferable.
[0023]
Further, by using the non-cylinder with elastic layer obtained in the present invention as a fixing belt for an image heating fixing device, it is possible to obtain a fixing belt having low compressibility and low compression set, and effectively toner. The toner can be fixed to the carrier and the toner carrier can be conveyed.
[0024]
FIG. 4 is a schematic cross-sectional view showing the image heating and fixing apparatus in the present embodiment. In FIG. 4, 33 is a fixing belt according to the present invention. Reference numeral 34 denotes a resin-made laterally long stay, which also serves as an inner surface guide member of the fixing belt 33 and a support for a heater 35 as a heating means. The fixing belt 33 is fitted on a stay 34 including a heater 35. The inner peripheral length of the fixing belt 33 and the outer peripheral length of the stay 34 including the heater 35 are, for example, about 3 mm larger than the fixing belt 33, and therefore the fixing belt 33 has a peripheral length with respect to the stay 34 including the heater 35. It fits loosely in the room. Reference numeral 31 denotes a pressure roller as pressure means for forming a fixing nip portion by sandwiching the fixing belt 33 with the heater 35.
[0025]
In the image heating and fixing apparatus according to the present invention, the electrostatic toner image T on the recording material S is fixed by applying heat and pressure at the nip portion. A recording material S as a heated material carrying an unfixed toner image conveyed to the image heating and fixing device on the upper surface is composed of a fixing belt 33 and a pressure roller 31 at a fixing nip portion of the heater 35 and the pressure roller 31. During the passage, the heat of the heater 35 is received through the fixing belt 33 and the toner image T is heated and fixed.
[0026]
(First embodiment)
Hereinafter, the present invention will be described in more detail with reference to embodiments, but these do not limit the present invention.
The shape of the expanded core 20 inserted into the thin-walled cylinder in the present invention is shown in FIG. The outer diameter of the expanding core 20 is larger than the minimum inner diameter in the axial direction of the thin cylinder 3 formed into a non-straight cylindrical shape (crown 3a, reverse crown 3b, or taper 3c) to be inserted, and preferably is a thin cylinder. 3 is equal to or larger than the maximum inner diameter in the axial direction. The expansion core 20 is provided with an air exhaust port 21. When the thin cylinder 3 is inserted, air is supplied to the expansion core 20 from an air supply device (not shown), and the air is ejected from the air exhaust port 21. The thin cylinder 3 is expanded, and the expanded core 20 can be inserted into the thin cylinder 3 formed in a non-straight cylindrical shape. The thin-walled cylinder 3 into which the tube expansion core 20 is inserted is corrected to the tube expansion core shape and temporarily becomes a straight cylinder shape.
[0027]
FIG. 2 is a schematic view showing a coating state by an extrusion type annular coating apparatus according to the present invention, and the uncured resin 2 flows through the annular head 1 and is applied to a thin cylinder 3 into which a tube expansion core 20 is inserted. FIG. 3 shows the situation and the configuration of the annular head 1. The uncured resin 2 stored in the cylinder part 4 is pressurized by depressing the piston 5 at a constant speed to become a constant flow rate, and flows from the liquid feed pipe 8 into the injection port 7 of the annular head 1. The annular head 1 is composed of a cylindrical portion 1a, a storage portion 1b, and a coating portion 1c, and the resin flowing in from the injection port 7 is filled in an annular liquid reservoir 11 surrounded by the cylindrical portion 1a and the storage portion 1b. It is. From there, the uncured resin 2 is extruded from the annular nozzle 13 through a narrow annular slit 12 surrounded by the cylindrical portion 1a, the storage portion 1b, and the coating portion 1c. At this time, the uncured resin 2 extruded on the surface of the thin cylinder 3 is continuously moved by relatively moving the thin cylinder 3 and the annular head 1 (in the figure, the movement of the thin cylinder in the direction of the arrow is shown). The coating method is preferably applicable to the coating of an uncured resin having a high viscosity. The relative movement between the thin cylinder 3 and the annular nozzle 1 at this time is shown as a horizontal movement in FIG. 2, but can be applied to an annular coating apparatus in the vertical direction or in the oblique direction. The thin cylinder 3 coated with the uncured resin 2 is removed from the tube expansion core 20 by the same air pressure as that during insertion, and the shape of the thin cylinder 3 is returned to the original non-cylinder. Thereafter, the uncured resin 2 is cured to obtain a non-cylinder with a resin layer.
[0028]
The thin cylinder 3 in the present invention is a non-cylindrical cylindrical shape, and the difference between the maximum inner diameter and the minimum inner diameter in the axial direction is 300 μm or less, but in consideration of the insertability into the tube expansion core 20, it is more preferably 200 μm or less. is there.
As the uncured resin 2 used in the present invention, it may be liquid as long as it is applied, but it may be solidified by curing, may be thermosetting, and silicone rubber is particularly preferable.
[0029]
(Second Embodiment)
In the first embodiment, when a tube expansion core is inserted into a non-cylinder-shaped thin cylinder to correct it into a straight cylinder, an uncured resin is applied to the surface of the thin cylinder, and the uncured resin is cured. The non-straight cylinder with a resin layer was obtained by removing the cylindrical expansion core.
However, as described in the first embodiment, when the resin layer is applied, the thin cylinder is corrected to a straight cylinder, and when the resin layer is cured, the non-cylinder shape is restored. A film thickness variation of about 2% occurs in the axial direction with respect to the difference between the maximum inner diameter and the minimum inner diameter. The film thickness fluctuation does not affect the function of the fixing belt at all, but the second embodiment provides a method for suppressing the film thickness fluctuation.
[0030]
Hereinafter, although a 2nd embodiment is described in detail, these do not limit the present invention at all.
The uncured resin used in the second embodiment may be a resin that is liquid at the time of coating and is cured by applying heat, or may be a silicone rubber. Among these, silicone rubber is preferable because of its high heat resistance, and addition type silicone rubber is more preferable as the resin layer of the fixing member.
[0031]
In the present invention, the curing of the uncured resin layer is performed in two stages of pre-curing and main curing, and pre-curing is performed in a state where the thin cylinder is corrected to a straight cylindrical shape, the core is removed from the thin cylinder, and the thin cylinder The main curing is performed in a state where the non-right cylindrical shape is again formed. Thereby, it is possible to obtain better film thickness uniformity of the resin layer than in the first embodiment.
Here, at the time of pre-curing the resin is increased in viscosity than when uncured, has become still state of liquid, during the curing of the resin has become fully cured to the solid state.
[0032]
The heating temperature during temporary curing of the uncured resin in the present embodiment is preferably 10 ° C. or higher and 90 ° C. or lower. More preferably, it is 20 degreeC or more and 80 degrees C or less, More preferably, it is 30 degreeC or more and 70 degrees C or less. By setting such a temperature range, it is possible to prevent fluctuations in the film thickness due to insufficient temporary curing, and because the curing of the uncured resin proceeds excessively or the thin cylinder undergoes plastic deformation due to heat, the thin cylinder The phenomenon that the difference between the maximum inner diameter and the minimum inner diameter becomes small can be prevented. Further, the heating temperature during the main curing is preferably 100 ° C. or higher and 300 ° C. or lower. More preferably, it is 120 degreeC or more and 250 degrees C or less. More preferably, the temperature is 150 ° C. or higher and 230 ° C. or lower.
[0033]
【Example】
Example 1 Production of Fixing Belt with Resin Layer (Belt 1) Thin Crown Cylinder (Minimum Inner Diameter 30.00mm, Maximum Inner Diameter 30.20mm) 3b and Expanded Core (Outer Diameter 30.21mm) as shown in FIG. ) 20 was used. The thin cylinder 3 was expanded while air was ejected from the air exhaust port 21, and the expanded core 20 was inserted into the thin cylinder. With the expanded core inserted into the thin cylinder, the addition type silicone resin (DY39-561 (trade name): manufactured by Toray Dow Corning Silicone Co., Ltd.) is used as an uncured resin using the annular coating device shown in FIG. Was applied to a film thickness of 300 μm. Thereafter, the expansion core 20 was removed from the thin-walled cylinder 3b, and the thin-walled cylinder was again heated to 200 ° C. in a non-straight cylindrical shape to be cured.
[0034]
(Comparative Example 1) Manufacture of fixing belt (belt 2) with resin layer The inverse crown-shaped thin cylinder (minimum inner diameter 30.00 mm, maximum inner diameter 30.20 mm) 3b shown in FIG. In addition, using the annular coating apparatus shown in FIG. 2, an addition-type silicone uncured resin (DY35-561 (trade name): manufactured by Toray Dow Corning Silicone Co., Ltd.) as an uncured resin has a thickness of 300 μm. Coated.
[0035]
The outer diameter and the resin layer thickness of the thin-walled cylinder with the resin layer of Example 1 and Comparative Example 1 manufactured as described above were measured. FIG. 5 shows the measurement of the outer diameter of the fixing belt of Example 1 (thick line) and Comparative Example 1 (thin line). FIG. 5 shows the fixing belt of Example 1 (thick line) and Comparative Example 1 (thin line). The resin layer thickness of (Belts 1 and 2) is measured. As a measuring method, an average of 25 points with a pitch of 25 mm in the axial direction (horizontal axis) and an average of 8 points with a 45 ° pitch in the circumferential direction (vertical axis) were measured with a laser length measuring device at room temperature. Regarding the film thickness of the resin layer in FIG. 5, the measurement is performed only with a thin cylinder in advance, and the value obtained by subtracting the measurement value of only the thin cylinder from the measurement value after molding the resin layer on the surface of the thin cylinder is obtained. It was. The outer diameter measurement result in FIG. 5 is almost the same in Example 1 (thick line) and Comparative Example 1 (thin line), but the measurement result of the resin layer thickness in FIG. ) In the axial direction of the film thickness of Example 1 (thick line) is uniform, and it can be seen that a non-rectilinear cylinder with a resin layer having a uniform resin film thickness is obtained. Here, the film thickness of the fixing belt of the present embodiment of FIG. 5 is slightly thicker near the center. This is because the thin cylinder is corrected to a straight cylinder when the resin layer is applied, and the resin layer This is because when the is cured, it is returned to the inverted crown shape. This occurs in any shape of crown, reverse crown, and taper. The film thickness fluctuates by about 2% in the axial direction with respect to the difference between the maximum inner diameter and the minimum inner diameter of the thin cylinder. There is no influence on the function of the belt.
[0036]
In the image heating and fixing apparatus, the fixing belts (belts 1 and 2) manufactured in Example 1 and Comparative Example 1 are used, and a plurality of sheets of paper on which unfixed toner is carried are conveyed and inserted. evaluated. As a result, with the fixing belt of Example 1, a high-quality fixed image with good paper transportability was obtained. However, although the fixing belt of Comparative Example 1 has good transportability of paper, image unevenness, which is considered to be a variation in heat conduction due to a difference in film thickness in the axial direction of the resin layer, has occurred.
[0037]
(Example 2) Manufacture of fixing belt (belt 3) with a resin layer The thin cylinder, the expanded core and the uncured resin are the same as those in Example 1, and the resin layer is formed on the thin cylinder by the same method as in Example 1. Formed. Thereafter, with the expanded core 20 inserted into the thin cylinder 3b, an addition-type silicone resin is used as the uncured resin, and the uncured resin is temporarily cured at 50 ° C., and the expanded core is removed from the thin cylinder. In a state where the cylinder was again made into a non-cylindrical shape, main curing of the uncured resin was performed at 200 ° C. FIG. 6 shows the measurement of the resin layer thickness of the fixing belts (belts 1 and 3) of Example 1 (thin line) and Example 2 (thick line). From the measurement result of FIG. 6, it can be seen that the film thickness of the fixing belt of Example 1 that is slightly thicker near the center is eliminated in the fixing belt of Example 2.
[0038]
【The invention's effect】
As described above, according to the present invention, a straight cylindrical core is inserted into a thin cylinder formed into a non-cylinder shape, and the thin cylinder is corrected to a straight cylinder shape. By forming the cured resin layer, a non-right cylinder with a resin layer having a uniform thickness can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a tube expansion core in Example 1. FIG.
FIG. 2 is a schematic view showing a coating state by an annular coating apparatus in Example 1. FIG.
FIG. 3 is a schematic cross-sectional view illustrating a coating state and a configuration of an annular head in Example 1.
FIG. 4 is a schematic cross-sectional view showing an image heating and fixing apparatus in Embodiment 1.
FIG. 5 is a diagram illustrating a measurement result of a film thickness of a resin layer of a fixing belt in Example 1 and Comparative Example 1.
6 is a diagram showing the measurement results of the resin layer thickness of the fixing belt in Example 2 and Comparative Example 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1a Cylindrical part 1b of an annular head Storage part 1c of an annular head Application part 35 of an annular head Heater 2 Uncured resin S Recording material 3 Thin cylinder 3a Crown 3b Reverse crown 3c Taper T Toner image 4 Cylinder part 5 Piston 7 Inlet 8 Liquid feed tube 11 Liquid reservoir 12 Annular slit 13 Annular nozzle 20 Expanded core 21 Air exhaust port 31 Pressure roller 33 Fixing belt 34 Stay 35 Heater S Recording material T Toner image

Claims (2)

A state in which a straight cylindrical core having an outer diameter equal to or larger than the maximum inner diameter in the axial direction of the thin cylinder is inserted into a thin cylinder formed into a non-cylindrical shape, and the thin cylinder is corrected to a straight cylindrical shape in using the annular coating apparatus on said thin cylindrical to form an uncured resin layer having a uniform thickness, removing the core after the formation of the uncured resin layer, the non-linear cylindrical shape again said thin cylindrical after, the method of manufacturing a resin layer with a non-straight cylinder, characterized in that have a step of curing the uncured resin layer. The manufacturing method of the non-right cylinder with a resin layer of Claim 1 which performs temporary hardening of an uncured resin layer before removing a core in the said process .

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