JPH11311930A - Blade for electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To consecutively produce a blade consisting of thermosetting polyurethane, to enhance production efficiency, to facilitate and simplify the automatization of a production processes, and to reduce cost. SOLUTION: This blade 2 is obtained by mixing and stirring the liquid of polyurethane prepolymer being the raw material component of thermosetting polyurethane and the liquid of cross-linking agent, discharging the mixture U of them into a metallic mold whose cross section is recessed of a molding drum 20, and then heating it through an endless belt 24 moving by following the drum 20 in a state where it abuts on the outer peripheral surface of the drum 20, consecutively molding a belt-like blade molding S having fixed width, cooling the molding S and then cutting it to fixed length.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic copying machine, a printer, a facsimile, and the like, and a cleaning blade for removing residual toner on a photosensitive member (drum, belt, etc.) and a toner in a developing device. The present invention relates to a blade for an electrophotographic apparatus (hereinafter, also referred to as a blade) such as a developing blade which forms a thin film while being triboelectrically charged, and more particularly to a blade made of thermosetting polyurethane.

[0002]

2. Description of the Related Art As shown in FIG.
Usually, it is used in a state of being attached to a metal holder 3, but conventionally, it is manufactured by any one of the following manufacturing methods.

One is a manufacturing method called a centrifugal molding method. As shown in a partial sectional view of FIG. 4 (a), a urethane prepolymer containing a terminal isocyanate group is contained in a cylindrical drum 51. And a cross-linking agent (also referred to as a chain extender or a curing agent), and agitated liquid material A is injected thereinto, the drum 51 is rotated at a high speed via a rotating shaft 52, and the inner circumference of the drum 51 is centrifuged. A layer of liquid material A having a constant thickness is formed on the surface, and a reaction is performed for a predetermined time while heating at the same time to produce a cylindrical polyurethane sheet molded product.
Stop turning and carefully remove by hand. Then, the cylindrical polyurethane sheet molded product is cut linearly at one location in the length direction to form a flat polyurethane molded product B.
After that, the molded polyurethane sheet B is held at a predetermined temperature for a predetermined time, subjected to secondary crosslinking, and then aged at room temperature. Next, as shown in FIG. 4B, a large number of rectangular flat blades 2 are manufactured by cutting the blades 2 into predetermined dimensions. Then, one side edge of each blade 2 is adhered to the tip edge of the metal holder 3 with an adhesive as shown in FIG. 3 to complete the blade tool 1 as a final product.

Another manufacturing method is a manufacturing method called a molding method. As shown in FIG. 4C, a metal holder 3 to which an adhesive is applied in advance is set in divided molds 55 and 56, A liquid material A obtained by mixing and stirring a urethane prepolymer containing an isocyanate group and a cross-linking agent is added to a split mold 5.
5 and 56, and the mixture is heated for a predetermined time to cure the blade 2 and is integrally formed with the holder 3. Next, the split mold 55
-After releasing the molded product by opening 56, and after a secondary crosslinking and aging process, the tip of each blade 2 is cut with a cutter to cut out an edge (ridge), so that the blade tool 1 as a product is Complete.

Further, the liquid material A is discharged into a molding groove having a concave cross section formed on the outer peripheral surface of the rotating molding drum,
After increasing the viscosity for a predetermined time, a method is also conceivable in which the endless belt is pressed against the outer peripheral surface thereof, pressurized and heated to continuously form a belt-shaped blade.

[0006]

However, each of the blades manufactured by the above-mentioned conventional manufacturing methods has room for improvement in the following points.

[0007] Centrifugal molding method: there is an advantage that a large number of blades can be obtained by a single molding, but it takes a long time from injection to removal because of batch processing. Also, in the blade forming process, a large number of blades are formed at once, but after the forming process, it is necessary to bond each blade to the holder one by one. Difficult to automate. In addition, the molded product is likely to have a thickness variation due to a run-out and a variation in the injection amount generated when the molding drum is rotated at a high speed.

[0008] Molding method: It is necessary to change the mold for each product type such as different dimensions of the blade and the shape of the holder, and for mass production, prepare a considerable number of molds of each type. In addition, the size of the heating furnace for accommodating and transporting the molds becomes large, so that a large space is required for the installation place of the entire equipment, and the equipment cost is increased. In addition, since the changeover of the setup takes time, the production efficiency is low. Further, it is necessary to intermittently inject dies into the dies which are conveyed one by one, and it is necessary to perform a loss shot (continuous discharge of the liquid material A) between the dies or the intermittent operation of the casting machine. In the former, a material loss occurs, and in the latter, a weighing error easily occurs.

Liquid A (uncured polyurethane)
Is discharged into a continuous mold, pressurized, and heated to form a belt-shaped blade. Since a device to be removed is required, a problem that the entire device becomes large is expected.

[0010] The present invention has been made in view of the above points, and can continuously produce high-quality blades using thermosetting polyurethane, has high production efficiency, and has a simple structure to automate the production process. It is an object of the present invention to provide a blade for an electrophotographic apparatus which is an apparatus which is easy to use and can reduce the equipment cost.

[0011]

In order to achieve the above object, a blade for an electrophotographic apparatus according to the present invention comprises a liquid material of a polyurethane prepolymer which is a raw material component of a thermosetting polyurethane and a liquid material of a crosslinking agent. A mixture is prepared by mixing and stirring, and the mixture is heated to a predetermined temperature and discharged into a groove engraved with a predetermined size on the outer peripheral surface of a rotating forming drum, and the groove and the groove are covered with the groove. A predetermined time is heated while filling the mixture with a space formed by an endless belt that rotates following the forming drum, and a band-shaped blade formed product having a predetermined width and thickness is continuously formed. After molding, the blade molding is cooled and then cut into predetermined lengths. Here, the mixture of the polyurethane prepolymer means a reaction product of a high-molecular-weight polyol and a polyisocyanate, and includes a polyurethane pseudo-prepolymer having a low blending ratio of the high-molecular-weight polyol. The cross-linking agent may include only a cross-linking agent (chain extender) or a high-molecular-weight polyol.

According to the blade for an electrophotographic apparatus of the present invention having the above-mentioned components, the endless belt forms a space (also referred to as a cavity) by covering the groove on the outer peripheral surface of the forming drum, and forms the space in the space. The mixture (fluid uncured polyurethane) is filled and heated and cured while rotating to form a belt-shaped blade molded product. The rotation speed and the discharge amount of the forming drum are finely adjusted and balanced by means described later, but the balance is further improved by further allowing the liquid level of the mixture in the space to be changed, and the filling is further improved. Without causing dents due to shortage,
Further, since no pressure is applied, so-called burrs do not occur and material loss is small. In addition, since the blade molded product can be continuously taken out in series, it can be formed into a necessary length according to the number of products, and the blade molded product can be cut into fixed lengths according to the product length. .
Therefore, the resulting product is obtained by bonding the blade molding to the holder supporting the blade with an adhesive. As described above, according to the production method of the present invention, a required number of blade moldings of a fixed length can be continuously produced in a required number, so that there is no waste and the blade moldings can be sent out one by one, Automation is easily achieved, including the adhesion of the blade molding to the holder.

According to a second aspect of the present invention, the component of the high molecular weight polyol mixed with at least one of the liquid material of the polyurethane prepolymer and the liquid material with the crosslinking agent has a number average molecular weight of 500 to 5,000 and an average number of functional groups ( f) is 2 ≦
It is more preferable that f ≦ 4. In addition, the number average molecular weight of the high molecular weight polyol component is preferably 1000 to 300.
A range of 0 is more desirable. By casting this composition, the reaction proceeds smoothly, and the physical properties of the obtained blade are also preferable. That is, when the molecular weight of the high-molecular-weight polyol component is less than 500, the viscosity is too low, the operability is poor, and the final physical properties of the obtained polyurethane are not good. Conversely, if the molecular weight exceeds 5,000, the viscosity becomes too high and mixing becomes difficult. Further, when the average number of functional groups (f) is f = 1, the polymer is not polymerized because it is a monool, and when f ≧ 5, it is too polyfunctional, so that the viscosity of the polymer increases and the physical properties decrease.

It is preferable that one surface of the blade (a surface forming a scraping ridge line on one side edge) is mirror-finished. Since this blade is mirror-finished on one side, a scraping ridge line can be sharply formed by a cutter (blade), so that the blade can be suitably used as a blade for an electrophotographic apparatus, particularly as a cleaning blade. Further, by automating all the manufacturing steps, the production cost can be reduced.

According to a fourth aspect of the present invention, the blade may be a blade used in a cartridge integrally formed with a photosensitive drum, a toner, a blade, and the like used as an engine part of an electrophotographic apparatus. For example, JP-A-6
It is suitably incorporated in an exchange unit described in JP-A-118857, a process cartridge described in JP-A-6-318022, and the like.

By the way, as the component of the polyurethane elastomer for producing the blade according to the present invention, conventionally known components can be used. Examples of the high molecular weight polyol include polyoxyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polyoxytetramethylene glycol, and polyether polyols such as bisphenol A and alkylene oxide adducts such as ethylene oxide and propylene oxide of glycerin, and adipine. Polymerization reaction of dibasic acids such as acid, phthalic anhydride, isophthalic acid, maleic acid and fumaric acid with glycols such as ethylene glycol, propylene glycol, 1,4 butanediol, 1,6 hexanediol and trimethylolpropane The resulting polyester type polyol, polycaprolactone diol, polycarbonate diol and the like can be mentioned.

The number average molecular weight of these high molecular weight polyols is 500 to 5000, particularly preferably 1000 to 30.
00 range. Examples of the diisocyanate compound include tolylene diisocyanate, 4,4 diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and 1,4 cyclohexane diisocyanate. As a chain extender,
Examples include low molecular weight diols such as ethylene glycol, 1,4 butanediol, diethylene glycol, 1,6 hexanediol, and neopentyl glycol, and diamines such as ethylenediamine, hexamethylenediamine, and isophoronediamine. Desirably, a low molecular weight diol is used. Further, if necessary, trimethylolpropane, triethanolamine, glycerin, and ethylene oxide and propylene oxide adducts thereof may be added as polyfunctional components. These polyols and diisocyanate compounds may be reacted by any one of a one-shot method, a pseudo-prepolymer method, and a prepolymer method employed in a conventional polyurethane production method. Use of the polymer method results in stable and good physical properties of the obtained product.

In the production of the above polyurethane, O
The equivalent ratio of H group / NCO group is preferably 0.8 to 1.05, and more preferably 0.85 to 1.0 in view of the physical properties of the polyurethane to be formed.
It is in the range of 0. A reaction accelerator may be used if necessary. The reaction accelerator is an imidazole derivative represented by the following general chemical formula, and specific examples thereof include:
From the viewpoint of chemical structure, 2-methylimidazole, 1,2-dimethylimidazole, and the like, which have high reaction temperature dependency, can be given.

[0019]

Embedded image In the formula, R represents hydrogen, a methyl group, or an ethyl group.

The reaction accelerator is used as an effective amount in an amount of 0.01 to 0.5 part by weight, based on 100 parts by weight of the prepolymer.
It is preferably used in the range of 0.05 to 0.3 parts by weight.
Desirably, those having further temperature sensitivity or delayed action are preferably used because the pot life can be extended and the demolding time can be shortened. Specific examples thereof include 1,8-diazabicyclo (5,4,0) undecene-7-organic acid salt referred to as block amine and 1,5-diazabicyclo (4,3,0) nonene-5-ene.
Organic acid salts or mixtures thereof are mentioned. In the present invention, a commercially available two-component mixing casting machine used for mixing and stirring the liquid material of the polyurethane prepolymer, which is a raw material component of the thermosetting polyurethane, and the liquid material of the crosslinking agent can be used. It is preferable to use three or more plunger types for the metering pump in consideration of the quantitative accuracy, but a gear pump type can also be used. In particular, in the manufacturing apparatus of the present invention (claim 5), it is necessary to use a reaction accelerator to make a fast curing formulation in order to obtain a predetermined hardness at the time of demolding. A small-capacity type, as disclosed in Japanese Patent No. 11389, in which stagnation in a mixing chamber is prevented and heat generation due to reaction heat is suppressed is preferable.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a blade according to an embodiment of the present invention; FIG. 1 is an overall front view schematically showing an example of a blade manufacturing apparatus used in an electrophotographic apparatus, FIG. 2A is a perspective view showing another example of a cleaning blade manufacturing apparatus, and FIG. FIG. 3 is a cross-sectional view showing a part of the forming drum 20 of FIG.

As shown in FIG. 1, a blade manufacturing apparatus 1
0 has two tanks 11 and 12, each tank 11
Piping 1 with metering pumps 13 and 14 interposed from outlet 12
5 and 16 are mixing heads (two-liquid fixed-quantity mixing casting machine)
17. The mixing head 17 and the tanks 11 and 12 are respectively connected to the circulation pipes 15a and 15a.
16a. Further, the mixing head 17 is provided with two liquid substance inlets at the upper end, and rotatably supports the stirring rotor 17b at the upper central part thereof in a chamber provided with a liquid discharge port at the lower central part. , A known structure that is driven to rotate by the upper motor 17c. The flow rate of the metering pumps 13 and 14 and the mixing head 17 can be controlled with high precision by selecting a drive motor, preventing stagnation in the chamber, and the like.

The forming drum 20 has a forming groove 21 having a concave cross section over the entire outer circumferential surface of a cylindrical metal drum (see FIG. 2A), and the outer circumference of the groove 21 is formed by an endless belt 24. A space is formed by covering the space, and the space is filled with the infusion solution U (see FIG. 2B). The forming drum 20 is made of, for example, hard aluminum, stainless steel, or the like. In this example, a heating steam or oil jacket (not shown) is provided inside the forming drum 20, and the outer peripheral surface of the forming drum 20 has a predetermined temperature ( (Around 145 ° C.). The central portion of the forming drum 20 is rotatably supported by a horizontal rotating shaft 23, and rotates counterclockwise at a predetermined speed by a driving device (not shown). The AC servo motor is used as the drive unit, and feedback of the load fluctuation is performed.
A large reduction ratio between the drive motor and the forming drum 20 is taken, and the rotation speed of the motor is increased (for example, 1500 rpm level) to adjust the fluctuation of the rotation speed to within ± 0.3% (conventionally, about ± 1.5 %).

An endless belt 24 for forming a molding space (a mold) made of a metal strip such as stainless steel is in contact with the outer peripheral surface of a substantially lower half of the forming drum 20, and the endless belt 24 is The pre-heating roller 26 pre-heats the belt 24, the guide roller 28 adjusts the running of the belt, the tension roller 27 applies tension to the endless belt, and the cooling roller 25 cools the endless belt 24. It follows and rotates in the same direction. The endless belt 24 is provided with a plurality of heaters 41 adjacent to each other, for example, as shown in FIG. 2A, and is heated to a predetermined temperature (around 145 ° C.). The curing speed of the polyurethane can be adjusted also by this temperature. Further, the preheating roll 26 shown in FIG.
The contact start point between the outer peripheral surface of the endless belt 24 and the endless belt 24, that is, the heating start position of the injection liquid U can be adjusted. With this configuration, the injection liquid U, which is a polyurethane raw material,
The heating time between the point a and the point b can be finely adjusted without changing the peripheral speed of the drum 20 in accordance with the variation in the reactivity of the drum 20.

Between point c and point a of the drum 20, FIG.
Although not shown, a mold release agent processing device 29 for cleaning the inside of the molding groove 21 and spraying the mold release agent (see FIG. 2A).
Is included. Further, a similar device (not shown) can be attached to the return side of the endless belt 24 (for example, between the tension roll 27 and the guide roll 28). As the cleaning device in the groove 21, for example, a device in which a cleaning cloth wound up in a roll shape is drawn out and the inside of the groove 21 is wiped is used.

A cooling conveyor 31 is provided horizontally adjacent to the right cooling roll 25. The cooling conveyor 31 has an endless conveyor belt 31a made of metal such as stainless steel stretched between two rolls 32 and 33. A cooling device 34 is provided below the cooling conveyor 31 to supply cooling water (arrows) to the endless belt 3.
The endless conveyor belt 31 is sprayed on the lower surface of the endless conveyor belt 1a and circulated cooling water to the rolls 32 and 33.
The blade molding S is cooled through a. Note that FIG.
As in the other embodiment shown in FIG.
In the vicinity of the transfer start position of the first horizontal transfer section, a ceramic linear blade 35 having a low friction coefficient can be fixed by being inclined in the upstream direction on a surface perpendicular to the upper surface of the endless conveyor belt 31a. . Thereby, one side edge of the blade formed body S can be continuously cut while forming a sharp ridge line. In this case, although not shown, the blade 3
It is preferable to equip 5 with a cutting fluid supply device.

Adjacent to the roll 33 of the cooling conveyor 31 downstream of the roll 33, a slack detector 52, a feed roll 50, a cutting device 37 and a conveyor 51 are arranged in this order.
The slack detector 52 attaches a pair of upper and lower sensors 54 and 55 to a pair of vertical columns 53 and guides the blade molding S between them to detect the slack state.
The feed roller 50 receives the signal of the slack detector 52 and sends the blade formed product S to the cutting device 37 at a predetermined speed (speed higher than the cooling endless conveyor belt 31a).
The cutting device 37 has a lower blade 37b and an upper blade 37a and cuts the blade molded product S into a predetermined length. Conveyor 5
1 conveys the cut blade molding S to the next step (a metal fitting step, a width cutting step (ridge line forming step), etc.). The operation of the next step can be performed on the conveyor 51.

Next, as described above, the manufacturing apparatus 1 of this embodiment
The method of manufacturing a blade for an electrophotographic apparatus by the manufacturing apparatus 10 will be described with reference to FIG. The prepolymer and the cross-linking agent were respectively charged into tanks 11 and 12 of a two-part fixed-quantity mixing casting machine, and heated, depressurized, stirred, and defoamed. The prepolymer thus obtained and the cross-linking agent are mixed by the measuring pumps 13 and 14 into the mixing head 1.
7 and discharged into the forming groove 21 (see FIG. 2 (a)) of the forming drum 20 whose temperature has been adjusted to 145 ° C. from the discharge port 17a while uniformly stirring and mixing. At this time, the forming drum 20 is rotating counterclockwise at a predetermined speed (one rotation / 80 seconds), and the necessary amount corresponding to the peripheral speed of the drum 20 and the engraving depth and width of the groove 21 are continuously changed. Injected.

The injection liquid U is supplied to the discharge port 17a of the forming drum 20.
145 ° C. after the reaction was started between point a just below the point a and point b (the position immediately before the endless belt 24 starts contacting).
Is heated and held between the point b and the point c of the forming drum 20 by the endless belt 24 for forming heated. Thereby, the urethane polymerization reaction of the injection liquid U is almost completed, and the blade molding S having the required width and thickness and a smooth mirror surface is continuously formed. In this example,
The time required for the infusate U to rotate and move from point a to point b is 1
Although 0 second and the moving time from the point b to the point c are set to 50 seconds, as described above, the forming drum 2
By changing the position of point b by approach / separation operation with respect to 0, and changing the rotation angle between point a and point b and the rotation angle between point b and point c, fine adjustment of the reaction and molding time of the infusate U it can.

The strip-shaped blade formed product S thus continuously formed is separated from the groove 21 of the forming drum 20 at the point c, and is guided onto the endless conveyor belt 31a of the cooling conveyor 31. Endless conveyor belt 31a
Is cooled by the cooling device 34, the blade formed product S is kept on the endless conveyor belt 31a at normal temperature (20 ° C.).
It is transported while being cooled down to near.

Then, the cooled blade molding S is
Looseness detector 52 and feed roll 5 from cooling conveyor 31
0, guided to the cutting device 37 and the conveyor 51. The slack detector 52 includes a sensor 54 mounted on a support 53.
55, the blade molding S is passed through the feed roll 5
Lead to zero. The feed roll 50 sandwiches the blade formed product S and runs faster than the cooling conveyor 31. Therefore, when the blade formed product S comes into contact with the upper sensor 54, it stops, and when it comes into contact with the lower sensor 55, feed starts. Then, the production speed of the blade molding S and the processing speed of the cutting device 37 are adjusted (do not apply excessive tension to the blade molding S). The cutting device 37 includes an upper blade 37a and a lower blade 3
The blade molding S is guided between 7b and cut into a predetermined length (length as a product). Thus, the manufacturing process of the flat blade 2 (FIG. 3) cut into a predetermined length is completed.

The blade 2 manufactured in this manner is
As shown in FIG. 3, one side edge of the blade holder 1 is bonded to the metal holder 3 with an adhesive to complete the blade tool 1 as a final product. When the blade tool 1 is a blade that needs to form a sharp ridge (a cleaning blade or the like), another side edge of the blade 2 on the side where the metal holder 3 is adhered is cut with a ceramic cutter or the like. To form a ridge. Further, in the case of the present invention, unlike the conventional centrifugal molding method, the blades 2 are manufactured one by one as many as required, so that the step of bonding the holder 3
Alternatively, the blades 2 may be processed one by one in the ridge line forming step, so that these steps can be easily automated.

Next, another example of the blade manufacturing apparatus 10 of the present invention will be described with reference to FIG. Manufacturing apparatus 10 'of this example
Are different from the above embodiment in the following points. That is, as shown in FIG. 2A, a large number of semi-cylindrical heaters 41 are provided between point a and point b on the outer peripheral surface of the forming drum 20, and the heater 41 between point b and point c of the forming drum 20. Between them, heaters 41 are provided on the inner peripheral surface side of the endless belt 24 and on the inner peripheral surface of another portion for heating the endless belt 24, respectively. In addition, the number of rollers 25 to 27 around which the endless belt 24 is wound is reduced from four to three. Between point c and point a of the forming drum 20,
A release agent processing device 29 is provided.

In the cooling conveyor 31, as a cooling means for the endless belt 31a, a part of the lower traveling portion is extended downward in a concave shape through rollers 44 to 47 and is inserted into a cooling device (not shown). I try to insert it. At the stage when the blade molding S has been transferred onto the endless belt 31a, the temperature of the blade molding S is 145 ° C.
It is in a relatively high temperature state nearby and is not sufficiently cooled, so that the cutting force is small. Therefore, in the present embodiment, the cutting margin S 'of one side edge of the blade molding S is continuously cut by the ceramic cutting tool 35 having a low friction coefficient by using the conveying force of the endless belt 31a. ing. As a result, a sharp ridge having a width and a linearity required for the cleaning blade is formed. Further, the blade molded product S is held on the horizontal and flat endless belt 31a until it is transferred onto the support plate 36, and is hardened by being cooled, and at the same time, is shaped into a blade as a product. .

Further, the lower blade is not used in the apparatus for cutting the blade formed body S into a predetermined length, and the thick blade is placed on the support plate 36 below the upper blade 37a as shown in FIG. The liner 42 made of roll paper, soft synthetic resin tape, etc.
Each time 7a moves up and down, it is fed out from one roll and wound on the other roll by the width of the upper blade 37a. Then, a table 43 that can reciprocate in a direction perpendicular to the support plate 36 is provided continuously, and the blades 2 cut by the upper blade 37a are arranged in order on the table 43. Other configurations are the same as those of the above-described embodiment, and thus the same reference numerals are given to the same components as those in FIG. In the above two embodiments, the structure of the cooling conveyor, the method of cutting the side edge portion, and the method of cutting the length can be combined according to the specifications.

[0036]

EXAMPLES Table 1 below shows the formulation and the molding conditions of the thermosetting polyurethane used in the present invention, and Table 2 shows the physical properties and dimensions of the obtained blade molded product.

Example 1 As shown in Table 1, a predetermined amount of polycaprolactone ester diol (average molecular weight: 2000) was heated and stirred at 70 ° C. for 3 hours under reduced pressure (5 mmHg) to dehydrate it.
This was charged into a reaction vessel, and subsequently, 4,4 diphenylmethane diisocyanate was added to the reaction vessel and stirred at 70 ° C. for 1 to 4 hours under a nitrogen gas atmosphere to obtain a liquid urethane preform having a residual isocyanate group content of 7.0%. A polymer was obtained.
On the other hand, as shown in Table 1, as a crosslinking agent component, predetermined amounts of 1,4-butanediol, trimethylolpropane and 1,
2 Dimethylimidazole was heated at 70 ° C. for 3 hours under reduced pressure (5
mmHg), and the mixture was dehydrated by heating and stirring to obtain a crosslinking agent having a hydroxyl equivalent of 45.

The prepolymer and the cross-linking agent obtained as described above were respectively charged into tanks 11 and 12 of a two-part fixed-quantity mixing casting machine, and heated and heated to the liquid temperature shown in Table 1.
Stirred. This is supplied to the mixing head 17 by the measuring pumps 13 and 14 so that the equivalent ratio shown in Table 1 is obtained, and the molding groove of the molding drum 20 whose temperature is adjusted to 145 ° C. from the discharge port while uniformly stirring and mixing. 21 was discharged. The subsequent manufacturing process is performed in the same manner as described in the manufacturing process using the manufacturing apparatus 10.

Example 2 The high molecular weight polyol in the prepolymer component was changed from polycaprolactone ester diol (average molecular weight 2000) to polyethylene adipate diol (average molecular weight 200
A blade was manufactured by the same manufacturing method as in Example 1 except that the blade was replaced with 0).

Example 3 The same procedure as in Example 1 was carried out except that the difference in viscosity between the prepolymer and the crosslinking agent was reduced and the mixing ratio of the prepolymer and the crosslinking agent was changed to 1: 1 by the pseudo-prepolymer method. The blade was manufactured by the manufacturing method.

Example 4 Same as Example 1 except that the high molecular weight polyol in the pseudo-prepolymer component and the crosslinking agent component was changed from polycaprolactone ester diol (average molecular weight 2000) to polyethylene adipate diol (average molecular weight 2000). The blade was manufactured by the manufacturing method.

The blades of any of the embodiments have the same physical properties and high dimensional accuracy as those of the conventional centrifugal molding method and mold molding method, and are sufficiently practical for use as blades. Met.

[0043]

[Table 1] (Note) 1) Polycaprolactone ester diol (Molecular weight 2000) 2) Polyethylene adipate diol (Molecular weight 2000) 3) 4,4 Diphenylmethane diisocyanate 4) Same as that used for preparation of prepolymer 5) 1, 2 Dimethylimidazole

[0044]

[Table 2] (Note) 1) According to JIS, K-6301 vulcanized rubber physical test method. 2) The image was mounted on a commercially available copying machine, and the image obtained after 10,000 copies was visually observed. All were good. 3) After the test, the blade was removed and its frictional state was examined with a microscope. In each case, it was equivalent to the conventional molding method with very little wear. 4) The surface of the photoreceptor after the test was visually observed. All were good.

Incidentally, the present invention is not limited to the manufacture of a blade for an electrophotographic apparatus, but is also suitable for a use suitable for a thermosetting polyurethane strip, for example, a screen printing polyurethane squeegee blade or the like. It is.

[0046]

As is apparent from the above description,
The electrophotographic device blade of the present invention has the following excellent effects.

(1) The blade of claim 1 cannot be obtained by a conventional thermoplastic polyurethane melt extrusion method because it is possible to mold a thermosetting polyurethane elastomer which is continuous in a belt shape. The blade which maintains the excellent properties (abrasion resistance, heat resistance, etc.) of the thermosetting polyurethane can be automated and manufactured by a simplified manufacturing process with high productivity. In addition, equipment costs can be reduced. Furthermore, since the endless belt is not particularly pressurized, there is no material loss due to overflow, and a pressurizing device and a device for removing burrs are not required, so that the device is simple and inexpensive.

(2) In the blade according to the second aspect, the reaction is smoothly performed, and a blade maintaining the properties of the thermosetting polyurethane can be obtained.

(3) The blade according to the third aspect is mirror-finished on one side, so that the scraping ridge line can be sharply formed by a cutter or the like, so that the quality is high and the cost is low.

(4) The blade for an electrophotographic apparatus cartridge according to the fourth aspect is inexpensive and has excellent cleaning properties, abrasion resistance and the like.

[Brief description of the drawings]

FIG. 1 is an overall front view schematically showing a blade manufacturing apparatus according to the present invention.

2 (a) is a perspective view showing another example of the blade manufacturing apparatus according to the present invention, and FIG. 2 (b) is a forming drum 20 of FIG.
It is sectional drawing which shows a part of.

FIG. 3 is a partially omitted perspective view showing a blade tool provided with the blade of the present invention.

4 (a) and 4 (b) show an example of a conventional blade manufacturing method. FIG. 4 (a) is a cross-sectional view (part) of a drum-shaped mold in a centrifugal molding method. FIG. 4B is a partial plan view showing a state in which the polyurethane sheet is expanded, and FIG. 4C is a cross-sectional view of a split mold in a molding method.

[Explanation of symbols]

 1: Blade tool 2: Blade 3: Holder 10:10 ': Manufacturing device 17: Mixing head 20: Forming drum 21: Forming groove 24: Endless belt 31: Cooling conveyor 34: Cooling device

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 31:00 (72) Inventor Toshiharu Taniguchi 3-2-1-15 Meiwadori, Hyogo-ku, Kobe-shi, Hyogo BANDO CHEMICAL CO., LTD. 72) Inventor Shinta Tani 3-2-1-15 Meiwadori, Hyogo-ku, Kobe City, Hyogo Prefecture Inside Bando Chemical Co., Ltd.

Claims (4)

[Claims] A mixture is prepared by mixing and stirring a liquid material of a polyurethane prepolymer, which is a raw material component of a thermosetting polyurethane, and a liquid material of a cross-linking agent. The mixture is heated to a predetermined temperature and rotated. The mixture is discharged into a groove portion engraved with a predetermined size on the outer peripheral surface of the forming drum, and the mixture is filled in a space portion formed by the groove portion and an endless belt that runs around the forming drum and rotates following the forming drum. Heating for a predetermined period of time while filling, continuously forming a band-shaped blade molded product having a predetermined width and thickness, cooling the blade molded product, and cutting the blade at predetermined lengths to form the blade molded product. An electrophotographic blade for an electrophotographic apparatus. 2. A high molecular weight polyol component to be mixed with at least one of a polyurethane prepolymer liquid and a liquid with a crosslinking agent has a number average molecular weight of 500 to 50.
2. The blade for an electrophotographic apparatus according to claim 1, wherein the average number of functional groups (f) is 2 ≦ f ≦ 4. 3. The electrophotographic blade according to claim 1, wherein one surface of the blade is mirror-finished. 4. The blade for an electrophotographic apparatus according to claim 1, which is a blade used for a cartridge for an electrophotographic apparatus.