JPH10207217A - Fur brush developing roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress the occurrence of deflective image by using brush fiber having a contact angle of a specific value or more, when a liquid incorporating the components of a developer used drops. SOLUTION: A developing roller 2 is constituted of a freely rotatable core body 6, an adhesive layer 7 with which the surface of the core body 6 is coated and a developing brush 9 consisting of a large number of brush fibers 8 electrostatically flocked on the adhesive layer 7,.... The surface of the developing roller 2 produced like this is coated with a coating processing agent 10. As this agent 10, a processing agent having a contact angle of 40 deg. or more, when the liquid incorporating at least one kind of component of the developer used, that is, toner 3 drops, such as a fluorinated compound and a hydrocarbon compound is mentioned. The developing roller 2 constituted like this is used to peel an excess developer from the brush fibers 8 by a toner regulating member and attain control for an optimum developer quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fur brush developing roller used in an electrophotographic apparatus utilizing an electrostatic image developing system such as an electrophotographic copying machine, a printer, and a facsimile.

[0002]

2. Description of the Related Art Various types of developing devices for use in the above electrophotographic apparatus have been proposed. For example, there is a magnetic toner as a developer, and the magnetic toner is attracted by a magnetic roller, and the attracted magnetic toner is exposed to light. Transcription to the body has been done.

However, in the method of supplying magnetic toner using such a magnetic roller, not only is the magnetic roller expensive, but also the adjustment of the gap between the magnetic roller and the transfer member is delicate, often in units of 0.1 mm. Needs the accuracy of
There is also a disadvantage that a mechanism for satisfying the accuracy becomes complicated. In particular, when a two-component toner is used, the carrier itself has a limited life, and it is necessary to periodically replace the carrier, for example, every 10,000 copies or 20,000 copies. is there. Further, since a magnetic material having a different color is internally added to the magnetic toner itself, it has been technically difficult to convert the magnetic toner into a color toner.

In order to solve the above-mentioned disadvantages, there have been proposed some developing methods using a non-magnetic toner made of a resin such as polyester or styrene-acrylic resin instead of the magnetic toner used as the developer. I have. For example, a fur brush developing method is known in which soft bristles such as beaver bristles are formed into a cylindrical brush, and nonmagnetic toner is adhered to the brush. This fur brush development method
Since a magnetic two-component developer is not used, there is no need for a complicated apparatus which must always maintain a constant ratio of magnetic toner and carrier particles.

When developing using the above-mentioned fur brush developing method, it is important to increase the developing density and develop a clearer image. For this purpose, it is proposed, for example, to increase the length of the bristles of the brush to soften the bristles.
With such long hair, the amount of triboelectric charge is increased,
Not only can the amount of charge on the non-magnetic toner be increased, but also the contact area with the photoconductor increases, so that the amount of toner transported to the photoconductor increases, and the speed of the developing roller can be increased.

In order to manufacture the fur brush developing roller, first, an adhesive is applied to a core body to form an adhesive layer, and thereafter, a brush fiber constituting a developing brush by using a high voltage. Is charged and caused to fly by Coulomb force, so that brush fibers are implanted in the adhesive layer. FIG. 4 shows a simple principle diagram. A core body 6 having an adhesive layer 7 on its surface is disposed above, and an electrode plate 11 is provided below the core body 6.
And the electrode plate 11 and the rotating shaft 12 of the core 6 are connected to a high-voltage generator 13. And
A large number of brush fibers 8 are placed on the electrode plate 11,
By turning on the high voltage generator 13 and rotating the core 6, the brush fibers 8,... Located on the upper part of the electrode plate 11 fly in order and are implanted in the adhesive layer 7.

The fur-brush developing roller manufactured in this way takes in non-magnetic toner as a developer contained in a box into the brush fibers of the fur-brush developing roller, charges the non-magnetic toner appropriately, and exposes the photosensitive material. It is supplied to the latent image section of the body.

However, when a large amount of the non-magnetic toner contained in the box is taken into the brush fibers of the fur brush developing roller, the non-magnetic toner that does not touch the brush fibers is not charged and becomes an uncharged toner. When the toner is conveyed, the toner scatters on a portion other than the latent image portion on the photoreceptor, resulting in an image defect called “fog”.

In order to prevent the "fogging", as shown in FIG. 1, a non-magnetic toner is appropriately supplied to the brush fibers of the fur brush developing roller by the toner regulating member 5. Since the non-magnetic toner 3 taken in by the toner 8 strongly adheres to the brush fibers 8, it is difficult for the toner regulating member 5 to control the amount of the developer as shown in FIG. As shown in (b), extra non-magnetic toner 3A is supplied. In particular, in a low humidity environment, the moisture in the air decreases, the resistance value of the brush fiber increases, the brush fiber and the developer rub against each other, and the charge amount increases.
Will adhere to.

[0010]

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention aims to solve the above problem by using a fur brush developing method using a non-magnetic one-component toner and suppressing a defective image by using a fur brush. The point is to provide a developing roller.

[0011]

According to the present invention, there is provided a brush for forming a developing brush on the adhesive layer after forming an adhesive layer by applying an adhesive to the surface of the core body. In a fur brush developing roller configured by planting fibers, a brush fiber having a contact angle of at least 40 degrees when a liquid containing at least one component of a developer to be used is dropped is used. And

[0012] Further, after an adhesive is applied to the surface of the core to form an adhesive layer, the adhesive layer is used in a fur brush developing roller formed by implanting brush fibers constituting a developing brush on the adhesive layer. At least one of the components of the developer
A brush fiber surface-treated with a treating agent having a contact angle of at least 40 degrees when a liquid containing seeds is dropped is used. When the brush fibers according to the first and second aspects are used, the non-magnetic toner constituting the developer adhered to the brush fibers is easily peeled off, so that the fur brush developing roller is housed in the developing box. When the obtained non-magnetic toner is taken into the brush fibers of the fur brush developing roller, it can be easily controlled to an appropriate supply amount by the toner regulating member so as not to take in extra non-magnetic toner.

[0013]

FIG. 1 shows a fur brush developing device. The fur brush developing device includes a photoreceptor 1 rotatable clockwise, a developing roller 2 rotatable counterclockwise for contacting the surface of the photoreceptor 1 for development, and a developing roller 2 for developing. A toner supply box 4 for supplying a non-magnetic one-component toner (hereinafter, referred to as a developer) 3 which is a granular material constituting a developer, and a developing brush 9 of a developing roller 2 in the box 4 are shown in FIG. B) and a toner regulating member 5 arranged so as not to take in the excess developer 3A. The rotation directions of the photoconductor 1 and the developing roller 2 are not limited to the above directions.

As shown in FIGS. 2 and 3, the developing roller 2 includes a rotatable core 6, an adhesive layer 7 applied to the surface of the core 6, and an adhesive layer 7. And a developing brush 9 composed of a number of brush fibers 8 to be electrostatically planted. The surface of the developing roller 2 thus manufactured is coated with a coating agent 10. As a coating method, a case where the developing roller 2 is dipped (with a nap) on the coating treatment agent 10 or a case where the developing roller 2 is spray-coated on the surface of the developing roller 2 can be considered, but it is not limited to these methods.

The coating treatment agent 10 is a treatment agent having a contact angle of at least 40 degrees when a developer used, that is, a liquid containing at least one of the components of the toner 3 is dropped. Compounds, hydrocarbon compounds, silicone compounds and the like. The contact angle here means, for example, placing a water drop on a solid with a horizontal surface,
When a tangent is drawn from the point where this water droplet contacts the solid,
The angle between a tangent and a solid surface. By using the developing roller 2 configured as described above, the toner control member 5 separates the excess developer 3A from the brush fibers 8 as shown in FIG. The developer amount can be controlled.
The concentration of the coating agent 10 is adjusted so as to be uniform on the surface of the brush fibers 8 and to prevent several brush fibers 8 from being bundled and fixed when the coating agent 10 is dried. There is a need. The coating agent 10 may be previously applied to the brush fibers 8 before electrostatic flocking, or the brush fibers 8 themselves may be made of a material having a contact angle of 40 degrees or more. The liquid used as the dropping liquid for performing the contact angle measurement in the present invention, when the developer is a polyester-based liquid,
Polysizer W2380 (manufactured by DIC), AD-250
(Nippon Shokubai) and the like. On the other hand, when the developer is styrene acrylic, styrene,
Examples thereof include butyl acrylate and methyl methacrylate.

The core 6 is made of iron, aluminum, stainless steel,
In addition to being made of a metal such as brass, when the adhesive layer 7 is made of a conductive adhesive, a plastic or a plastic that has been subjected to a conductive treatment such as plating to obtain a structure that can be grounded at the time of electrostatic flocking. Paper or the like may be used. Further, by performing a blast treatment to roughen the surface of the core body 6 by colliding the surface of the core body 6 with glass beads, aluminum powder, or the like at a high speed, the adhesiveness with the adhesive can be improved. Further, by making the core body 6 into a hollow cylindrical shape and having a structure in which flanges are attached to both ends, the weight can be reduced, and the manufacturing cost and the running cost for rotation can be reduced.

As the kind of the adhesive constituting the adhesive layer 7, an adhesive of vinyl acetate type, acrylic type, urethane type, epoxy type or the like can be used. The adhesive itself is made of an elastic material, so that the adhesive layer 7 is made to have an elastic function so that the hair becomes easy to move and becomes a soft developing brush 9, and the contact with the photoreceptor 1 is made. There are also advantages such as a wider width. As the resin composition constituting the adhesive layer 7 having the elastic function, a resin composition having conductivity or semi-conductivity and containing a reactive organic material can be used. Examples of the resin composition include those whose main components are oxyalkylene-based, saturated hydrocarbon-based, urethane-based, or siloxane-based, and that contain a reactive organic material that becomes a solid from a liquid by a curing reaction. It is preferable to set the viscosity of the adhesive in the range of 3000 CPS to 10000 CPS.

The present invention is applicable not only to a fur brush developing roller, but also to a roller around an electrophotograph, for example, a charging roller for charging a photoreceptor, a transfer roller for removing and transferring toner charge when transferring from a photoreceptor to paper, and the like. The present invention can be applied not only to a copying machine but also to various electrophotographic apparatuses using an electrostatic image developing system such as a printer and a facsimile.

[0019]

According to the fur brush developing method using a non-magnetic one-component toner, the toner particles adhered to the brush fibers are reduced by using the brush fibers according to the first and second aspects. When the fur brush developing roller takes in the developer housed in the box into the brush fibers of the fur brush developing roller, the toner regulating member appropriately controls the toner so as not to take in excess developer. The supply amount can be easily controlled, and the occurrence of image defects can be reliably suppressed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view showing a configuration of a developing device.

FIG. 2 is a longitudinal sectional front view showing a main part of a brush developing roller.

FIG. 3 is a longitudinal sectional side view showing a main part of a brush developing roller.

FIG. 4 is a principle diagram showing an electrostatic flocking method.

FIG. 5A is a longitudinal sectional side view of a main part of a brush developing roller showing a state in which a developer is appropriately supplied to brush fibers;
(B) is a longitudinal sectional side view of a main part of the brush developing roller showing a state in which the developer is excessively supplied to the brush fiber.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photoreceptor 2 Developing roller 3, 3A developer 4 Toner supply box 5 Toner regulating member 6 Core body 7 Adhesive layer 8 Brush fiber 9 Developing brush 10 Coating agent 11 Electrode plate 12 Rotating shaft 13 High voltage generator

Claims (2)

[Claims] 1. A fur brush developing roller formed by applying an adhesive to the surface of a core to form an adhesive layer and then implanting brush fibers constituting a developing brush on the adhesive layer. A fur brush developing roller using brush fibers having a contact angle of at least 40 degrees when a liquid containing at least one component of a developer is dropped. 2. A fur brush developing roller formed by applying an adhesive to the surface of a core to form an adhesive layer and then implanting brush fibers constituting a developing brush on the adhesive layer. A fur brush developing roller, characterized by using brush fibers surface-treated with a processing agent having a contact angle of at least 40 degrees when a liquid containing at least one component of a developer is dropped.