JPH04333875A - Method for manufacturing developer carrier - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a developer carrier used in an electrophotographic developing device.

0002

2. Description of the Related Art A developing device that uses a developer carrier having at least an elastic layer and a magnetic field generating layer and develops a latent image by bringing a magnetic developer into contact with the latent image carrier has been proposed in Japanese Patent Application No. 2-58321 and others. ing.

[0003] In the above-mentioned developing device, by using a developer carrier having at least an elastic layer and a magnetic field generating layer, strict control of the developing gap is not necessary and the developing nip can be widened. Because the electrodes of the latent image carrier and developer carrier are close to each other across a wide developing nip, development is performed under an ideal developing electric field, making it possible to stably develop high-quality images. Furthermore, by arranging a magnetic field generation layer magnetized with a minute magnetic pole pitch, it is possible to easily form a thin layer of magnetic developer and uniformly transport the developer to the development area. , the quality of development can be improved. In particular, if the elastic body is a foamed material, the developer carrier will have extremely low hardness and soft contact will be possible in a wide development area, making it possible to develop even higher-definition images.

0004

[Problems to be Solved by the Invention] However, the elastic layer of the developer carrier must have extremely low hardness because the developer carrier contacts the latent image carrier, and is preferably made of a foam material. The carrier repeatedly undergoes local compressive deformation and recovery from the deformation, so the compression set is extremely small, and the surface of the elastic layer must be shaped to form an extremely uniform thin film on the elastic layer, which includes at least a magnetic field generation layer. , ease of processing, desirably smoothing of the surface of the elastic layer, good wettability between the coating material and the elastic layer, and local compression of the developer carrier. The adhesive strength with the coating must be sufficiently large so that the coating does not peel off during continuous deformation and recovery from deformation, and it is also desirable to have low cost, but an elastic layer that satisfies all of the above conditions is required. It has hitherto been impossible to form.

[0005] The elastic layer of a conventional developer carrier has been satisfactory to some extent in terms of hardness, compression set, and moldability of the surface of the elastic layer. The adhesive strength with the film was completely insufficient.

[0006] In conventional developer carriers, the problem is that the wettability of the elastic layer with respect to the paint is insufficient, and pinholes occur in the film, causing deterioration in image quality such as image stains and omissions. It had a point.

[0007] In addition, in conventional developer carriers, the adhesion strength with the coating film is insufficient, and due to repeated local compression and recovery from compression of the developer carrier,
Since the film easily peels off from the elastic layer, there was a problem in that the life of the developer carrier was extremely short.

[0008] In conventional methods for manufacturing developer carriers, no effective method has been found so far for improving the wettability of the elastic layer to the paint and the adhesive strength with the film.

[0009]

[Means for Solving the Problems] A method for manufacturing a developer carrier of the present invention is to provide at least an elastic layer and a magnetic field generating layer, which are used in a developing device that brings a magnetic developer into contact with a latent image carrier to develop the image. The method for manufacturing a developer carrier having the present invention is characterized by comprising a step of fixing an aluminum compound to an elastic layer.

0010

[Function] According to the method for producing a developer carrier of the present invention, by fixing an aluminum compound to the elastic layer, it is possible to improve the wettability of the elastic layer to the paint and the adhesive strength with the film.

As a result, even when the elastic layer is made of silicone rubber, which has low wettability and high mold releasability and is extremely difficult to form, an extremely uniform thin layer film with no pinholes can be obtained. can be formed on the elastic layer, and it is also possible to manufacture a developer carrier with a coating that is difficult to peel off from the elastic layer and has an extremely long life at low cost and in a simple process.

[0012] The details of the present invention will be explained below with reference to Examples.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the method for producing a developer carrier of the present invention, a step of fixing an aluminum compound to the elastic layer is carried out as a pre-step of forming a film having at least a magnetic field generating layer on the elastic layer.

[0014] As the elastic layer, it is possible to use known rubbers, elastomers, and plastic materials that can be formed into foams. For example, natural rubber, styrene-butadiene rubber, isoprene rubber, butadiene rubber, nitrile rubber, chloroprene rubber, silicone rubber, ethylene-propylene rubber, fluororubber, acrylic rubber, epichlorohydrin rubber, styrene resin, vinyl chloride, polyurethane, phenolic resin, It is possible to apply urea resin, epoxy resin, polyethylene, methacrylic resin, etc.

In the step of fixing an aluminum compound to the elastic layer, which is a feature of the method for producing a developer carrier of the present invention, a solution of an aluminum compound (hereinafter referred to as "aluminum treatment solution") is applied to the elastic layer. They are brought into contact with each other, and then, as necessary, treatments such as removing excess aluminum treatment liquid adhering to the elastic layer and drying the elastic layer are performed to fix the aluminum compound on the elastic layer.

[0016] As the aluminum compound, an organic aluminum compound is preferable. However, the present invention is not limited to the above.

Furthermore, as a solvent for the aluminum treatment solution, methyl ethyl ketone, n-propanol, n-hexane, etc. can be used. However, the present invention is not limited to the above-mentioned solvents.

As a method for bringing the aluminum treatment solution into contact with the elastic layer, known coating means such as brush coating, spray coating, dipping coating, roller coating, etc. can be applied. If the aluminum treatment solution contains a solvent that causes the elastic layer to swell, it is also possible to impregnate the elastic layer with the aluminum treatment solution. However, the present invention is not limited to the above method.

After fixing the aluminum compound on the elastic layer, a step of forming a coating having at least a magnetic field generating layer on the elastic layer is performed, and the method for forming the coating on the elastic layer is as follows:
It can be carried out in exactly the same manner as the conventional method for manufacturing a developer carrier.

[0020] In addition to the magnetic field generation layer, a conductive layer, an insulating layer, a float electrode layer, etc. can be appropriately formed as a coating on the elastic layer, and each layer can be coated by a known coating method such as spray coating, Concentric circles are formed sequentially from the inside of the coating by dipping coating, roller coating, plating coating, etc. For example, the magnetic field generation layer may be formed by plating or vapor deposition of a magnetic material, or by applying a magnetic paint composed of a magnetic material, resin, and solvent using a known coating method, to which a dispersant or the like is added as necessary. , can be formed by drying a coating film, etc.

[0021] The magnetic materials used in the magnetic paint include materials known as magnetic recording materials and magnet materials;
For example, a magnetic material containing at least one element among Fe, Ni, Co, Mn, and Cr, specifically, γ-
Fe2O3, Ba-Fe, Ni-Co, Co-Cr, M
Examples include n-Al. As the resin used to bind the magnetic material, resins known as magnetic recording materials such as polycarbonate, polyester, polyethylene, polyurethane, vinyl chloride/vinyl acetate copolymer, etc. can be used. As the solvent, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, ethanol, butanol, toluene, xylene, water, etc. can be used.

The conductive layer may be formed by plating or vapor deposition of Cu, Ni, Au, etc., carbon black, Ag, Cu, Fe,
It can be formed by applying a conductive paint in which conductive fine particles such as SUS are dispersed by a known coating method and then drying the coated film.

FIG. 1 is a schematic cross-sectional view of a developer carrier manufactured by the method for manufacturing a developer carrier of the present invention.

An aluminum compound is fixed on the elastic layer 4.

The developer carrier 2 has an elastic layer 4 and a coating 5 arranged concentrically around the outer periphery of a base 3 such as a shaft.

(Example 1) An aluminum treatment solution, which is a 1% by weight n-hexane solution of acetalkoxyaluminum diisopropylate as an aluminum compound, was applied to the elastic layer 4 made of silicone rubber formed on the substrate 3 by dip coating. Then, the aluminum compound was fixed to the elastic layer by air drying at room temperature.

After fixing the aluminum compound to the elastic layer, urethane resin is dissolved in an organic solvent, and γ-
Coating 5 with a magnetic field generating layer approximately 10 μm thick using magnetic paint in which Fe2O3 and conductive carbon black are dispersed.
was formed, and a developer carrier 2 was manufactured.

The wettability of the magnetic paint to the elastic layer on which the aluminum compound is fixed is very good, and the coating 5
No defects such as pinholes or cracks were observed.

[0029] Also, the coating 5 made of Sumitomo 3M Scotch Mending Tape (model number 810-1-18)
A tape peeling test was conducted, but no peeling occurred, indicating good adhesion.

FIG. 2 is a cross-sectional schematic view of a developing device that uses a developer carrier having at least an elastic layer and a magnetic field generating layer and brings a magnetic developer into contact with the latent image carrier to develop the image.

In this example, the developer carrier 2 manufactured by the manufacturing method of the present invention was used in the developing device shown in FIG. 2 to form an image.

The developer carrier 2 that transports the toner 1, which is a magnetic developer, holds and transports the toner 1 on the surface of the developer carrier 2 by the magnetic force of the magnetic field generating layer constituting the coating 5.

The magnetic field generating layer constituting the coating 5 is magnetized with multiple poles in the circumferential direction of the developer carrier 2, and the pitch of the magnetic poles is approximately 40 μm. Since the magnetic pole pitch is fine, the leakage magnetic flux of the magnetic field generation layer rapidly decreases with increasing distance from the surface of the magnetic field generation layer in the radial direction of the developer carrier 2, and only about one or two layers of toner 1 are attracted. ,
A uniform thin layer will form. The toner 1 held on the developer carrier 2 is further leveled evenly by a thin elastic blade 7 made of magnetic or non-magnetic metal or resin, and as the developer carrier 2 rotates, the toner 1 is spread onto the support electrode 8. Electrostatic image holding layer 9 on top
The latent image carrier 10 and the developer carrier 2 on which the latent image carrier 10 is formed are conveyed to a development area where they are in contact with each other via the toner 1. Further, the toner 1 is applied to the latent image carrier 1 by the potential contrast of the latent image carrier 10 and the developing bias applying means 11.
The electrostatic latent image adheres to the latent image carrier 10 and is visualized in response to a developing electric field formed by a bias applied to the supporting electrode 8 and the conductive layer 5 of the developer carrier 2.

600DP formed on the latent image carrier 10
I repeatedly developed the line latent image and solid latent image to form an image equivalent to 30,000 sheets of A4 size paper, but a 600DPI line image was formed on the latent image carrier 10 without being crushed, and a non-image was formed. It was possible to stably form a high-density solid image with an OD value of 1.4 or higher, with almost no background fog.

Furthermore, no cracking or peeling of the coating 5 of the developer carrier 2 was observed.

(Example 2) Aluminum The treatment liquid was applied to the elastic layer 4 and air-dried at room temperature to fix the aluminum compound on the elastic layer.

After fixing the aluminum compound to the elastic layer, a developer carrier 2 was produced in the same manner as in Example 1.

The wettability of the magnetic paint to the elastic layer on which the aluminum compound is fixed is very good, and the coating 5
No defects such as pinholes or cracks were observed.

[0039] Furthermore, a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, but no peeling occurred at all, indicating good adhesion.

Furthermore, as in Example 1, the developer carrier 2 of this example was used in the developing device shown in FIG. 2 to repeatedly form images, and images equivalent to 30,000 sheets of A4 size paper were formed. However, 600DP was placed on the latent image carrier 10.
The I line image was formed without collapse, there was almost no background fog in the non-image area, and a high density solid image with an OD value of 1.4 or more could be stably formed.

Further, no cracking or peeling of the coating 5 of the developer carrier 2 was observed.

(Example 3) Aluminum The treatment liquid was applied to the elastic layer 4 and air-dried at room temperature to fix the aluminum compound on the elastic layer.

After fixing the aluminum compound to the elastic layer, a developer carrier 2 was produced in the same manner as in Example 1.

The wettability of the magnetic paint to the elastic layer on which the aluminum compound is fixed is very good, and the coating 5
No defects such as pinholes or cracks were observed.

[0045] Also, a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, but no peeling occurred at all, indicating good adhesion.

Furthermore, as in Example 1, the developer carrier 2 of this example was used in the developing device shown in FIG. 2 to repeatedly form images, and images equivalent to 30,000 sheets of A4 size paper were formed. However, 600DP was placed on the latent image carrier 10.
The I line image was formed without collapse, there was almost no background fog in the non-image area, and a high density solid image with an OD value of 1.4 or more could be stably formed.

Furthermore, no cracking or peeling of the coating 5 of the developer carrier 2 was observed.

(Example 4) An aluminum treatment solution, which is a 1% by weight n-propanol solution of the aluminum compound of Example 1, was applied to the elastic layer 4 made of silicone rubber formed on the substrate 3 by a spray coating method, and then left at room temperature. The aluminum compound was fixed to the elastic layer by air drying.

After fixing the aluminum compound to the elastic layer, a developer carrier 2 was produced in the same manner as in Example 1.

The wettability of the magnetic paint to the elastic layer on which the aluminum compound is fixed is very good, and the coating film 5
No defects such as pinholes or cracks were observed.

[0051] Also, a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, but no peeling occurred at all, indicating good adhesion.

Furthermore, as in Example 1, the developer carrier 2 of this example was used in the developing device shown in FIG. 2 to repeatedly form images, and images equivalent to 30,000 sheets of A4 size paper were formed. However, 600DP was placed on the latent image carrier 10.
The I line image was formed without collapse, there was almost no background fog in the non-image area, and a high density solid image with an OD value of 1.4 or more could be stably formed.

Further, no cracking or peeling of the coating 5 of the developer carrier 2 was observed.

(Example 5) An aluminum treatment solution, which is a 1% by weight n-propanol solution of the aluminum compound of Example 1, was applied to the elastic layer 4 made of epichlorohydrin rubber formed on the substrate 3 by dip coating, and then left at room temperature. The aluminum compound was fixed to the elastic layer by air drying.

After fixing the aluminum compound to the elastic layer, a developer carrier 2 was produced in the same manner as in Example 1.

The wettability of the magnetic paint to the elastic layer on which the aluminum compound is fixed is very good, and the coating 5
No defects such as pinholes or cracks were observed.

[0057] Also, a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, but no peeling occurred at all, indicating good adhesion.

Furthermore, as in Example 1, the developer carrier 2 of this example was used in the developing device shown in FIG. 2 to repeatedly form images, and images equivalent to 30,000 sheets of A4 size paper were formed. However, 600DP was placed on the latent image carrier 10.
The I line image was formed without collapse, there was almost no background fog in the non-image area, and a high density solid image with an OD value of 1.4 or more could be stably formed.

Further, no cracking or peeling of the coating 5 of the developer carrier 2 was observed.

(Comparative Example 1) A coating 5 made of magnetic paint was formed on the elastic layer 4 made of silicone rubber formed on the substrate 3, leaving the elastic layer 4 completely untreated, in the same manner as in Example 1, and a developer carrier was prepared. 2 was manufactured.

The wettability of the magnetic paint to the elastic layer was poor, and defects such as pinholes and cracks were observed in the coating 5.

[0062] Furthermore, when a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, the coating 5 was easily peeled off almost 100%.

Furthermore, in the same manner as in Example 1, when an image was formed using the developer carrier 2 of this example in the developing device shown in FIG. As a result, omissions and fogging occurred in the image, and after repeated development, it became impossible to stably form an image on the latent image carrier after forming an image equivalent to 200 sheets of A4 size paper. It became impossible.

Furthermore, cracks and peeling were observed in the coating 5 of the developer carrier 2.

(Comparative Example 2) Methyl ethyl ketone as base material 3
The elastic layer 4 made of silicone rubber formed in the above was coated by dip coating, and after air drying at room temperature, a coating 5 made of magnetic paint was formed in the same manner as in Comparative Example 1 to produce a developer carrier 2.

The wettability of the magnetic paint to the elastic layer was poor, and defects such as pinholes and cracks were observed in the coating 5.

[0067] Furthermore, when a tape peeling test was conducted on the coating 5 in the same manner as in Example 1, the coating 5 was easily peeled off almost 100%.

Furthermore, in the same manner as in Example 1, when an image was formed using the developer carrier 2 of this example in the developing device shown in FIG. As a result, omissions and fogging occurred in the image, and after repeated development, it became impossible to stably form an image on the latent image carrier after forming an image equivalent to 200 sheets of A4 size paper. It became impossible.

Furthermore, cracks and peeling were observed in the coating 5 of the developer carrier 2.

Although the embodiments have been described above, the present invention is applicable not only to the above embodiments, but also to a wide range of methods for manufacturing developer carriers in developing devices such as electrophotography, particularly in developing devices such as printers, copying machines, and facsimile machines. Can be applied.

[0071]

Effects of the Invention As described above, in the method of manufacturing a developer carrier in which a film including a magnetic field generating layer is formed on the surface of an elastic layer according to the present invention, the elastic layer can be used as a coating material for forming a film. Even in cases where it is extremely difficult to form a film with low wettability and high mold releasability, it is possible to form an extremely thin, pinhole-free film on the elastic layer. It has very good adhesion to the elastic layer,
The present invention has the effect that a developer carrier having an extremely long life and capable of stably developing high-quality images can be manufactured at low cost and in a simple process.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of a developer carrier manufactured by the method for manufacturing a developer carrier of the present invention.

FIG. 2 is a cross-sectional schematic view of a developing device that uses a developer carrier having at least an elastic layer and a magnetic field generating layer and brings a magnetic developer into contact with the latent image carrier to develop the image.

[Explanation of symbols]

1 Toner 2 Developer carrier 3 Base 4 Elastic layer 5 Coating 7 Elastic blade 8 Support electrode 9 Electrostatic image holding layer 10 Latent image carrier

Claims (1)

[Claims] 1. A method for producing a developer carrier having at least an elastic layer and a magnetic field generating layer, which is used in a developing device for developing a latent image carrier by bringing a magnetic developer into contact with the latent image carrier, wherein an aluminum compound is added to the elastic layer. 1. A method for producing a developer carrier, comprising a step of fixing the developer to a developer.