JP2002136914A - Method for manufacturing oa roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture a developing roller and a transfer roller, which are coated with a coating material in uniform thickness, not generating the dripping of the coating material in a drying processe after the substrate of a roller is dipped in the coating material in order to form a coating film on the surface of the substrate of the roller. SOLUTION: In a method for manufacturing the developing roller and the transfer roller, including a process for forming a coating film on the surface of the substrate of the roller 1 by dipping the substrate of the roller 1 in the coating material, a plurality of the rollers 1 having the coating films formed to the surfaces of the substrates thereof are suspended in an almost vertical direction and air is sent to the rollers from below to above to dry the coating films.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an OA roller used in an electrophotographic apparatus such as a copying machine, a facsimile, a printer, etc., that is, a developing roller and a transfer roller.

[0002]

2. Description of the Related Art In recent years, with the progress of electrophotographic technology, an image forming apparatus such as a dry electrophotographic apparatus uses a polymer elastic member as a base material of an OA roller used for development and transfer. Attention has been paid. In these OA rollers, it is important to perform coating with uniform performance in order to obtain uniform high image quality.

[0003] In the dipping step of applying a paint to the surface of the substrate of the OA roller, it is necessary to dry the applied coating film. However, conventionally, the drying is generally left to natural drying, or a wind is applied from the lateral direction with the applied roller suspended from a hanger. However, the direction of the wind was not uniform for all hangers or rollers, and there was a difference in the drying time of the rollers between the windward side and the leeward side. In addition, when the wind is applied from the lateral direction, the drying time is different between the windward side and the leeward side even with respect to one roller, which causes a non-uniform coating film.

[0004] The base of the roller is dipped into the paint,
The method of forming a coating film is a very excellent method as a method for manufacturing a developing roller, but if the thickness of the coating film is uniform on the entire surface of the substrate, and the coating material is not dried uniformly,
Image problems occur. If the paint dries slowly, the paint will drool, and a thick liquid pool will form at the lower end edge of the leeward side of the vertical roller, making it impossible to use it as a product.

In an actual manufacturing site, usually, ten or more rollers are hung on one hanger, and the paint is dipped at one time. When the wind is blown to all these rollers from the lateral direction, it is extremely important that the wind speed is constant in terms of quality and productivity.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made in a drying step after a roller base is dipped into a paint in order to form a coating film on the surface of the roller base. An object of the present invention is to manufacture a developing roller and a transfer roller coated with a uniform thickness without dripping of the paint.

[0007]

Means for Solving the Problems In order to achieve the above object, the present inventors have repeatedly conducted experiments. As a result, the roller base was dipped into a coating material, whereby the surface of the roller base was coated. In a method of manufacturing a developing roller and a transfer roller including a step of forming a coating film, a plurality of rollers having a coating film formed on a substrate surface are suspended in a substantially vertical direction, and upward from below. It has been found that a uniform dipping process can be performed by blowing air to dry the coating film, and a high-quality developing roller and transfer roller can be obtained.

[0008] At this time, it has been found that a particularly preferable result can be obtained if the variation of the velocity of the air flow at various points on the surface of all the rollers is within ± 0.1 m / S. The present invention is based on such findings.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION There are the following methods for applying a constant velocity airflow from a substantially downward direction to at least ten or more rollers suspended vertically from a hanger.

One of them is to dispose a blower chamber for sending a uniform velocity air flow below a roller suspended from a hanger. This blower chamber can send uniform wind from a blower port by providing a straightening plate or a filter above a simple fan-type upward blower, or by providing a large number of small blowers, for example. It is desirable to measure and adjust the wind speed using a sensor or the like.

[0011] Further, since it is necessary to uniformly apply an air flow to all the rollers hung on the hanger, it is preferable to provide a large or small number of blower chambers as much as possible. When a large number of small blow chambers are provided, it is preferable to use one or more blow chambers for at least five rollers.
In this case, the air flow is blown substantially uniformly to each part of the roller, and the time required for drying and the degree of drying of each part of the roller can be made almost constant.

As the resin constituting the coating film applied to the surface of the base of the developing roller or the transfer roller, a crosslinkable resin is preferable. Here, the crosslinkable resin is a resin that self-crosslinks by heat, a catalyst, air, moisture, an electron beam, or the like,
Alternatively, it refers to a resin that is crosslinked by a reaction with a crosslinking material or another crosslinking resin.

More specifically, fluorine resin, polyamide resin, acrylic resin, alkyd resin, phenol resin,
Melamine resins, silicone resins, epoxy resins, polyether resins, amino resins, urea resins, and mixtures thereof. In particular, alkyd resins, phenolic resins, melamine resins, and mixtures thereof are excellent in maintaining the non-staining property of the roller and the abrasion resistance.

A catalyst and a crosslinking material are added to the above-mentioned crosslinkable resin as required. Examples of the catalyst include a radical catalyst such as a peroxide, a base catalyst, and an acid catalyst. Examples of the cross-linking agent include a polyol compound, a polyisocyanate compound, a polyaldehyde compound, a polyamine compound, and a polyepoxy compound.

In the present invention, the resin coating layer is formed by applying a coating liquid obtained by melting or dispersing a crosslinkable resin, a crosslinker and additives for each conductivity to a roller by a dipping method, and preferably at room temperature. It is formed by drying at an elevated temperature.

Solvents used for preparing the paint include alcohol solvents such as methanol, ethanol, isopropanol and butanol, ketone solvents such as acetone and methyl ethyl ketone, aromatic hydrocarbon solvents such as toluene and xylene, and hexane. Examples thereof include aliphatic hydrocarbon solvents, ester solvents such as ethyl acetate, ether solvents such as isopropyl ether, water, and mixtures thereof.

The paint applied to the surface of the substrate is an aqueous paint. This is because, in the case of a water-based paint, when the OA roller is dipped, dripping of the paint due to slow drying becomes a problem, and the use of the method of the present invention is significant.
In the case of a paint having good drying properties such as an oil-based paint, such a problem does not occur much.

Further, if any one of urethane, acrylic, and emulsion is used as the water-based paint, the effect of the method of the present invention is large.

Further, in the method of manufacturing an OA roller according to the present invention, the velocity of the air flow impinging on each part of the roller is not only applied uniformly from the lower side of the roller hung on the hanger, but also over the entire surface thereof. Is kept in a range of ± 0.1 m / S (or a range of ± 10%), preferably in a range of 0.9 to 1.1 m / S. If the speed of the air flow is too high, the drying will proceed too quickly, resulting in a dry state with a film only on the surface of the paint, and if the speed of the air flow is low, the drying will be too slow and the vertical The paint dries and accumulates on the lower part of the roller in the state, resulting in a so-called dripping state.

If the material of the substrate of the roller to be applied is solid rubber or urethane rubber, it is good in image formation.

Further, when the temperature of the air stream is higher than room temperature, the drying efficiency can be enhanced, which is advantageous.

The OA rollers, ie, the developing roller and the transfer roller, manufactured according to the method of the present invention are used in image forming apparatuses such as a plain paper copying machine, a plain paper facsimile machine, a laser beam printer, a color laser beam printer, and a toner jet printer. Attached and used suitably.

EXAMPLES Next, the present invention will be described in more detail with reference to examples. However, it goes without saying that the present invention is not limited by these examples.

Example 1 An acrylic paint as a water-based paint was dipped on a developing roller made of solid rubber. As shown in FIG. 1 and FIG. 2, forty rollers (1) are arranged on four hangers (2) arranged in the front, rear, left and right, respectively, and five (5) are arranged in two rows in front and rear to form one unit, It was suspended in a vertical state and lined up at equal intervals in front, rear, left and right.

Below the roller (1), a blower chamber (3) having a large number of blowers (not shown) is provided on the upper surface, and the air flow exiting the blower chamber (3) is controlled by all rollers.
Spray as uniformly as possible from below (1)
The paint on the surface of (1) was dried.

Nine measurement points (4) were provided at substantially equal intervals between the rows of rollers (1) arranged in front and back. At each measurement point (4), the velocity of the airflow hitting the lower part of the roller (1) in a vertical state was measured. Also, at that time, whether or not the coating of the paint has occurred on a part of the roller (1),
Further, it was measured whether or not there was a difference in the thickness of the coating film on the surface of the roller (1).

At nine measurement points (A) to (I), the measured wind speed, dripping, presence / absence of a circumferential film thickness difference, and evaluation are shown in the table.

[0028]

[Table 1]

From the measurement results, the following has been found. When the velocity of the air flow is 0.8 m / s or less,
Drying was slow and dripping occurred due to insufficient air flow over the top of each roller (1). The speed of the air flow is
At 1.5 m / s or more, the surface of the coating film dried rapidly, but did not sufficiently dry to the inside of the coating film, and only the surface became a dry state, or the roller (1) The wind in the top creates turbulence and, as in the case of crosswinds, individual rollers
In some cases, a roller (1) having uneven drying and a change in film thickness accompanying the drying unevenness was obtained on the upper part of (1).

When a similar experiment was conducted for the transfer roller, it was confirmed that substantially the same results as described above were obtained.

[0031]

According to the production method of the present invention, a high-quality developing and transferring roller can be obtained without producing defects such as dripping of the paint and unevenness of the film thickness.

[Brief description of the drawings]

FIG. 1 is a front view of a drying device showing a state when a roller is dried.

FIG. 2 is a plan view schematically showing a cross section taken along line II-II of FIG.

[Explanation of symbols]

 (1) Roller (2) Hanger (3) Ventilation chamber (4) Measurement point

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03G 15/16 103 G03G 15/16 103 4F042 // B05C 3/10 B05C 3/10 9/12 9/12 13/02 13/02 F term (reference) 2H032 AA05 2H077 AC04 AD06 AD22 DB14 FA13 3J103 AA02 EA20 FA18 GA02 GA57 GA58 GA60 HA04 HA54 4D075 AB01 AB34 AB56 BB24Z BB95Z CA47 DA15 DB02 DC16 EA05 4F040 AA04 BA47 CC16 CC19 CC19 BA04 BA13 DF02

Claims (10)

[Claims] 1. A method for manufacturing a developing roller, comprising a step of forming a coating film on the surface of a roller by dipping the substrate of the roller into a coating material. A method of manufacturing a developing roller, wherein the developing roller is suspended in a substantially vertical direction and blown upward from below to dry the coating film. 2. The method for manufacturing a developing roller according to claim 1, wherein the air is blown so that the wind speed of the wind hitting each roller is substantially uniform. 3. The blower according to claim 1, wherein the wind speed along the outer peripheral surface of the roller at an arbitrary height of one roller is substantially uniform at any position on the circumference of the roller. Item 3. The method for producing a developing roller according to Item 1 or 2. 4. The method for manufacturing a developing roller according to claim 2, wherein the fluctuation value of the wind speed is within ± 0.1 m / s. 5. The method for manufacturing a developing roller according to claim 1, wherein the wind speed is 1.5 m / s or less. 6. A method for producing a transfer roller, comprising a step of forming a coating film on the surface of a substrate of a roller by dipping a substrate of the roller into a coating material. A method of manufacturing a transfer roller, wherein the transfer roller is suspended in a substantially vertical direction and blown upward from below to dry the coating film. 7. The method for manufacturing a transfer roller according to claim 6, wherein the air is blown so that the wind speed of the wind hitting each roller is substantially uniform. 8. The air blower according to claim 1, wherein the velocity of the wind along the outer peripheral surface of the roller at an arbitrary height of one roller is substantially uniform at any position on the circumference of the roller. Item 8. The method for producing a transfer roller according to item 6 or 7. 9. The method for manufacturing a transfer roller according to claim 7, wherein the fluctuation value of the wind speed is within ± 0.1 m / s. 10. The method for producing a transfer roller according to claim 6, wherein the wind speed is 1.5 m / s or less.