JPH11351240A - Electrical conductive urethane foam roller and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a surface electric resistance and to reduce cost by soaking a urethane foam material cut into a fixed form in electrical conductive paint of specific electric resistance, and after dehydrating and drying, pressing a mandrel therein and joining together and polishing the outer surface. SOLUTION: Under the condition of a urethane foam material 23 of fixed size contracted in the lengthwise direction, it is bored into a hole 25 to be fitted with the outer diameter of a mandrel 27, and soaked in electrical conductive paint G with electric resistance <=10<3> Ω. For soaking, solvent and dilution liquid are mixed in the ratio of 1:1 in a vessel, and the urethane foam materials 23 are put in a rotary cage with a dehydrator as one unit of about 50 pieces therein. The rotary cage is rotated at high speed to be dehydrated, and the materials are taken out to be dried naturally or forcedly. Hot melt adhesive is spread on both sides of the outer circumference of the mandrel 27 at several positions and dried, the mandrel 27 is pressed in the hole 25, heated at about 100 deg.C to integrate hence both. This is finished into fixed outer diameter and polished into a roller 20. Thus the roller of surface electric resistance <=10<5> Ωcan be obtained at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductive urethane foam roller used as a toner supply roller for supplying a non-magnetic toner to a photoreceptor in a developing unit of a laser printer, a copying machine, a facsimile machine, and the like, and its production. The present invention relates to a method, particularly to a method capable of reducing the surface electric resistance value of a urethane foam material and significantly reducing the production cost.

[0002]

2. Description of the Related Art As shown in FIG.
In the case of (1), as the toner supply roller 5 in the developing unit 3, a metal magnet roller is used for the toner having a magnetic material, but a conductive urethane foam roller is used for the non-magnetic toner instead. ing. .
In the laser printer 1, the toner supply roller 5 charges a photoconductor (photosensitive drum) 7 as optical information by a laser scanner L in a laser printer 1, and causes the photoconductor 7 to contain toner. 5 is brought into contact, the surface is rolled, and the toner is transferred to the information portion. At this time, in particular, in the case of color printing, it is important that the image is transferred to the photosensitive member (photosensitive drum) 7 without variation. Therefore, the surface electric resistance value of the conductive urethane foam roller must be 10 ⁵ Ω or less. This is a condition under which the toner can be transferred with little variation.
The toner on the photoreceptor (photosensitive drum) 7 is transferred to the recording paper 11 by the corotron 9 and is printed and fixed by the fixing roller 13 of the fixing unit F.

Meanwhile, the conductive urethane foam roller 3 used as a toner supply roller in the above-mentioned laser printer or the like has been conventionally commercially available, and has a surface electric resistance of about 10 ⁶ Ω.

The conductive urethane foam roller 3 is made as shown in a flowchart of FIG. That is, a conductive urethane foam 15 having a surface electric resistance value of about 10 ⁶ Ω is purchased, this outer shape is cut into a rectangular shape in a unit of one roller, and a hole having the same inner diameter as the diameter of the cored bar is cut. . Then, an adhesive such as a hot melt adhesive is applied to the surface of the core metal 13 and dried. After the core metal 13 is pressed into the hole of the conductive urethane foam, it is heated to solidify the adhesive, and then the surface of the roller 3 is polished into a predetermined shape to finish.

[0005]

According to the above-mentioned conductive urethane foam roller, the surface electric resistance value shows a high resistivity of about 10 ⁶ Ω. Therefore, in recent laser color printers and color copying machines, There is a problem that color density varies. According to tests, it has been confirmed that if the surface electric resistance is as low as 10 ⁵ Ω or less, the color density does not vary. However, conductive urethane foam having such a low surface electric resistance value is not generally commercially available, and even if it can be manufactured, the commercially available price is high, and there is a problem that a low-priced conductive urethane foam roller cannot be manufactured. is there.

[0006] The present invention has been made in view of the problems in the conductive urethane foam and the method for producing the same,
It is an object of the present invention to provide a conductive urethane foam roller having a low surface electric resistance value, and to provide a manufacturing method for significantly reducing the manufacturing cost.

[0007]

A process according to claim 1 of a conductive urethane foam roller of the present invention According to an aspect of the urethane foam material which is cut into polishable sized into a predetermined shape of the roller, the electrical resistance value of 10 ³ After being immersed in a conductive paint of Ω or less, dehydrated and dried, the outer surface of the core is polished into a predetermined shape in a state where a core metal is pressed and adhered thereto.

According to a second aspect of the present invention, the conductive urethane foam roller is formed of a urethane foam material and has a surface electric resistance of 10 ⁵ Ω or less.

[0009]

According to the first aspect, the urethane foam material cut into a size capable of being polished into a predetermined shape of a roller is immersed in a conductive paint having an electric resistance value of 10 ³ Ω or less, and after being dehydrated and dried, The outer surface is polished to a predetermined shape in a state where the core metal is press-fitted and adhered to the core metal.
A conductive urethane foam roller of ⁵ Ω or less can be easily manufactured. And according to this manufacturing method,
Since the conductive urethane foam roller can be efficiently manufactured with simple equipment, it can be provided at low cost.

According to the second aspect of the present invention, the conductive urethane foam roller has a surface electric resistance of the roller of 10 ⁵ Ω or less. Therefore, it is possible to exhibit excellent toner supply performance as a roller for supplying non-magnetic toner, and when this conductive urethane foam roller is used in laser color printers, color copiers, etc., the variation in color density is reduced. In addition, clear laser color printing and color copying can be performed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a conductive urethane foam roller according to the present invention and a method for producing the same will be described with reference to the drawings. FIG. 1 is a perspective view of the conductive urethane foam roller of the present invention, and FIGS. 2 to 9 show steps of a manufacturing method.

The above-mentioned conductive urethane foam roller 20
As shown in FIG. 1, a conductive paint G is immersed (dipped) in a urethane foam material 23 polished into a predetermined shape.
By doing so, the surface electric resistance value shows a resistivity of 10 ⁵ Ω or less. The above-mentioned conductive urethane foam 2
A core metal 27 is press-fitted and adhered to the 0 hole 25.

The conductive urethane foam roller 20 of the present invention is configured as described above and functions as follows. First, the conductive urethane foam roller 20
Has a surface electric resistance value of 10 ⁵ Ω or less for the roller formed of the urethane foam material 23, so that when this is used in a laser color printer, a color copying machine, etc., the variation in color density is reduced. In addition, clear laser color printing and color copying can be performed.
Of course, clear printing and copying can be performed even in a monochrome printer or a copying machine. In addition, the conductive urethane foam roller 20 contacts the photosensitive member (photosensitive drum) to transfer the toner evenly, and of course, can exhibit excellent toner transfer performance.

Next, a method for manufacturing the conductive urethane foam roller 20 of the present invention will be described with reference to the process charts of the manufacturing method shown in FIGS. 2 to 9 and the manufacturing flowchart shown in FIG. First, as shown in FIG.
When the urethane foam body U provided as a 00 mm square and a length of 1000 mm is purchased, a predetermined size (16 mm
Roller piece 23A cut into squares (221.4 mm)
To buy as. At this time, the core metal 27 serving as a shaft is also purchased as a product processed to a standard size. Of course, the core metal 27 may be a self-manufactured product.

As shown in FIG. 3, the roller piece 23A is cut in the longitudinal direction, and the hole 25 adapted to the outer diameter of the cored bar 27 is cut into the inner diameter by a pipe-shaped cutter D or the like. .

The roller piece 23A is immersed in the conductive paint G. 4, the solvent G1 and the diluent G2 are mixed in the container 30 at a ratio of 1: 1, and the roller piece 23A is mixed with the dehydrator 40 as shown in FIG. Around 50 baskets are put into a rotating basket 43 with a unit, and the basket is lowered and immersed.

The conductive coating material G1 and the diluent G2 to be the conductive paint G are composed of components and contents as shown in FIG. The conductive coating material G1 includes carbon black (content: 5%) and toluene (content: 30).
%), Isopropyl alcohol (content: 40%), n
-Butyl alcohol (content: 20%), ethylene glycol monomethyl ether acetate (content: 5%)
Consists of The diluent G2 is toluene (content: 3).
0%), isopropyl alcohol (content: 35%),
It consists of diacetone alcohol (content: 35%). The conductive coating material G1 and the diluent G2 are mixed at a ratio of 1: 1 to form a conductive paint G. The electric resistance value of the conductive paint G indicates a measured value of 10 ³ Ω or less.

As described above, the roller piece 23A immersed in the conductive paint G, as shown in FIG.
3. Spin at high speed to dehydrate. Then, roller piece 2
3A is taken out of the centrifugal dehydrator 40 and air-dried or, as shown in FIG. 6, forcedly dried at 60 ° C. or lower for about 30 minutes by an electric heater 50 or the like.

Then, the core metal 27 is press-fitted and adhered to the dried roller piece 23A. That is, as shown in FIG. 7, first, the core metal 27 is prepared. On both sides of the outer periphery of the core metal 27, the hot melt adhesive S is applied at several places at intervals (or in a spiral shape), and is dried. In this state, the core metal 27 is
Press into the hole 25 of A. Thereafter, the roller piece 23A and the core metal 27 are heated at a temperature of about 100 ° C., and the hot melt adhesive S is melted to bond them. Thereafter, the mixture is solidified at room temperature, and the roller piece 23A is attached to the metal core 27.
Are integrated.

Roller piece 23A with core 27
As shown in FIG. 8, the outer periphery 23B is attached to a grinder or the like, and the outer periphery 23B is cylindrically ground by a grindstone B, and finish-polished to an outer diameter of a predetermined size. Through the above manufacturing steps, the conductive urethane foam roller 20 as shown in FIG. 9 is manufactured.

The conductive urethane foam roller 20
Is visually inspected for its appearance, and the surface electric resistance is measured. That is, as shown in FIG. 10, when the electric resistance value of the surface of the outer periphery 23B is measured by the electric resistance meter T, the surface electric resistance value of the outer periphery 23B of the roller is 10%.
It has been confirmed that it is less than ⁵ Ω.

As described above, according to the method for manufacturing the conductive urethane foam roller 20, the following effects can be obtained. First, a urethane foam material cut to a size that can be polished into a predetermined shape of a roller is immersed in a conductive paint having an electric resistance value of 10 ³ Ω or less, dehydrated and dried, and then pressed into a cored bar. Since the outer surface of the roller is manufactured by polishing the outer surface in a predetermined shape in a bonded state, the surface electric resistance value of the roller is 10 ⁵
A conductive urethane foam roller having a resistance of Ω or less can be obtained. According to this manufacturing method, a conductive urethane foam roller having a surface electric resistance value of 10 ⁵ Ω or less can be efficiently manufactured with simple equipment, and can be provided at low cost.

When the conductive urethane foam roller is used in a laser color printer, a color copying machine, or the like, the variation in color density is reduced, and clear laser color printing and color copying can be performed. .

[0024]

According to the manufacturing method of the first aspect, the urethane foam material cut into a size capable of being polished into a predetermined shape of a roller is immersed in a conductive paint having an electric resistance value of 10 ³ Ω or less, and is dehydrated. After drying, the core is press-fitted and bonded, and the outer surface is polished to a predetermined shape to produce a conductive urethane foam roller having a surface electric resistance of 10 ⁵ Ω or less. The equipment produces an effect that it can be manufactured efficiently and can be provided at low cost.

That is, since this is a manufacturing method in which only a urethane foam material is purchased at a low price, and this is cut into roller pieces, the conductive paint is immersed in the roller piece, so that the immersion efficiency of the conductive paint in the urethane foam material is reduced. Because it can be manufactured with small equipment.

According to the conductive urethane foam roller of the present invention, since the roller is formed of urethane foam material and has a surface electric resistance of 10 ⁵ Ω or less, it is used for a laser color printer, a color copying machine or the like. At this time, the variation in color density is reduced, and an effect that a clear laser color print or color copying can be performed is exhibited.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is a perspective view of a conductive urethane foam roller.

FIG. 2 shows an embodiment of the production method of the present invention, and is a cutting process diagram of urethane foam.

FIG. 3 shows an embodiment of the production method of the present invention, and is a view showing a step of punching a cut urethane foam.

FIG. 4 shows an embodiment of the production method of the present invention and is a process diagram of immersing a conductor in urethane foam.

FIG. 5 shows an embodiment of the production method of the present invention and is a dehydration step diagram of a conductive urethane foam.

FIG. 6 shows an embodiment of the production method of the present invention, and is a drawing showing a drying process of a conductive urethane foam.

FIG. 7 shows an embodiment of the production method of the present invention, and is a process diagram of press-fitting a core metal into a conductive urethane foam.

FIG. 8 shows an embodiment of the production method of the present invention, and is a polishing process diagram for shaving a conductive urethane foam roller.

FIG. 9 shows the embodiment of the manufacturing method of the present invention, and is a completed completed drawing of a conductive urethane foam roller.

FIG. 10 shows the embodiment of the present invention and is a cross-sectional view of a main part of a conductive urethane foam roller.

FIG. 11 shows the embodiment of the present invention and is a flowchart of a method for manufacturing a conductive urethane foam roller.

FIG. 12 shows an embodiment of the present invention and is an explanatory diagram of a conductive coating material component.

FIG. 13 is a principle diagram of a copying machine showing an example of using a conductive urethane foam roller.

FIG. 14 is a flowchart illustrating a method for manufacturing a conventional conductive urethane foam roller.

[Explanation of symbols]

 Reference Signs List 20 conductive urethane foam roller 23 urethane foam material 23A urethane foam piece 23B outer periphery 25 hole 27 core metal 30 container 40 dehydrator 50 electric heater G conductive paint G1 conductive coating material G2 diluent S hot melt adhesive U urethane foam body

Claims (2)

[Claims] 1. An urethane foam material cut to a size capable of being polished into a predetermined shape of a roller is provided with an electric resistance value of 10 ^3.
A conductive urethane foam roller manufactured by immersing in a conductive paint of Ω or less, dehydrating and drying, polishing the outer surface thereof to a predetermined shape in a state where a core metal is pressed and adhered to the core metal. Method. 2. A conductive urethane foam roller formed of a urethane foam material and having a surface electric resistance of 10 ⁵ Ω or less.