JP3111868B2 - Roll manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a roll such as a developing roll which comes into contact with toner, and more particularly to a method for producing a roll having an outermost layer excellent in toner releasability. The present invention relates to a method for producing a roll capable of producing a roll.

[0002]

2. Description of the Related Art In an electrophotographic copying machine or the like, for a roll such as a developing roll which comes into contact with toner, it is required as an important characteristic to prevent the toner from adhering to the roll surface. For this reason, the outermost layer of such a roll is formed using a fluororubber composition having excellent release properties, and in order to further improve this release property, the fluororubber composition is used as a release agent. Contains silicone oil.

[0003]

However, since the compatibility between the fluororubber and the silicone oil is poor, the silicone oil may form a large aggregate and exist in the fluororubber matrix. In such a state, for example, in the developing roll of the electrophotographic copying machine, the supply of silicone oil to the roll surface becomes uneven,
As a result, toner adheres to the portion where the silicone oil is insufficient, and this becomes a starting point, which further spreads the toner adherence, and eventually causes toner filming.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for producing a roll capable of producing a roll having an outermost layer having excellent toner releasability.

[0005]

In order to achieve the above object, a method for producing a roll according to the present invention comprises applying a coating solution of a fluororubber composition to an outer peripheral surface of a roll substrate, and then vulcanizing the coating solution to obtain a fluorine-containing composition. This is a method for producing a roll for forming an outermost layer made of rubber, in which the following (A) is used as the fluororubber coating liquid. (A) At least one of a reactive silicone oil and a reactive fluorine oil is blended with a fluororubber dissolved in a solvent, and the viscosity is increased by stirring under heating, and the stirring is stopped when the viscosity becomes constant. A coating solution of the fluororubber composition prepared by the above method.

[0006] The above-mentioned roll base is a roll base having no outer layer formed thereon.
It refers to a layer on which an elastic layer serving as an innermost layer or an intermediate layer is formed.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, the method for producing a roll according to the present invention is characterized by using a special fluororubber composition coating solution for forming the outermost layer. Describing the coating liquid of this special fluororubber composition, it contains a fluororubber and at least one of the above-mentioned reactive silicone oil and reactive fluorine oil. Then, when the above-mentioned fluororubber is dissolved in a solvent, and the above-mentioned reactive silicone oil or the like is added thereto and stirred under heating conditions, the viscosity increases. Then, when the increase in the viscosity becomes slow and reaches a constant value, the stirring is stopped to prepare a coating liquid of the fluororubber composition. In the fluororubber composition coating liquid thus obtained, the particles of the above-mentioned reactive silicone oil and the like become fine particles having a particle size of about 50 μm or less, and react with the fluororubber molecules to react and fix between the fluororubber molecules. Is done. This reaction fixation is based on a chemical bonding reaction between a reactive group such as a reactive silicone oil and a fluororubber molecule. In this state, the fluororubber itself is not vulcanized and is not crosslinked. Then, a vulcanizing agent dissolved in a solvent is added to the coating solution of the fluororubber composition, and the vulcanizing agent is applied to the outer peripheral surface of the roll substrate, dried if necessary, and then heated and vulcanized to form an outermost layer. To form
In the outermost layer of the roll thus obtained, fine particles made of a reactive silicone oil or the like, which is a toner release agent, are uniformly dispersed in the fluororubber matrix and fixed by reaction. This state is shown in the schematic diagram of FIG. 1. In the fluororubber matrix 1, particles 2 formed from a reactive silicone oil or the like react with the fluororubber molecules 1 a and are chemically bonded. This chemical bond varies depending on the type of reactive group such as reactive silicone oil. In this reaction fixing, all the reactive silicone oils and the like do not need to be chemically bonded, and the particles are reactively fixed mainly by the reactive silicone oil and the like located on the surface of the particles. And, as described above, the particle size of the particles 2 is:
It is about 50 μm or less and is uniformly dispersed. In this case, for example, in the developing roll having the outermost layer formed using the rubber composition, the reactive silicone oil or the like as the release agent does not ooze out as a large aggregate. As a result, the developing roll maintains high toner releasability for a long period of time, thereby preventing occurrence of toner filming.

Next, the present invention will be described in detail.

[0009] The rubber composition used in the method for producing the roll of the present invention comprises a fluororubber and a reactive silicone oil (component (a)).
And at least one of reactive fluorine oil (component (b)).

The fluororubber is not particularly limited and conventionally known ones can be used. However, tetrafluoroethylene-polypropylene (TFE-polypropylene) is used because of its low polymer viscosity and good dispersibility of the filler. It is preferable to use a PP) copolymer, and the following general formula (1)
It is particularly preferable to use a random copolymer having a structure represented by

[0011]

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In the above formula (1), the ratio of each of the repeating parts m, n, and p is represented by a weight ratio of m: n: p = (30 to 30).
60): (10 to 40): It is preferable to use one set to (10 to 40), and particularly preferably, m:
n: p = (30-50) :( 30-40) :( 20-3
0).

Next, the reactive silicone oil (component a) and the reactive fluorine oil (component b), which are blended with the fluororubber, are release agents for the toner. They may be blended, or one of the above-mentioned two components may be blended alone.

The reactive silicone oil (component a) and the reactive fluorine oil (component b) are both at least selected from the group consisting of a hydroxyl group, an amino group, a mercapto group, an epoxy group, a carboxyl group and a methacryl group. Preferably, it has one reactive group. As mentioned above, these reactive groups react with the fluororubber, whereby the particles formed from the oil are fixed in the fluororubber matrix. The mode of this reaction fixing is shown below for each of the above reactive groups.

[Hydroxy group]

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[Amino group]

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[Mercapto group]

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[Epoxy group]

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[Carboxyl group]

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[Methacryl group]

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These reactive groups are located at the terminal (including both terminals) and side chains of the molecular chain, and differ depending on the type of oil and the like.

Of the above reactive groups, a hydroxyl group, an amino group, and a mercapto group are preferred because of their excellent reactivity, and an amino group is particularly preferred. For reasons of thermal stability, the average molecular weight of the reactive silicone oil (component a) is in the range of 300 to 150,000, and the average molecular weight of the reactive fluorine oil (component b) is 200 to 20,000.
And the average molecular weight of both is particularly preferably from 1500 to 20,000. Furthermore, the total blending ratio (a + b) of the reactive silicone oil (component a) and the reactive fluorine oil (component b) is determined by the ratio of fluororubber 1
0.5 to 10 parts by weight (hereinafter abbreviated as “parts”)
A range of 0 parts is preferred, and a particularly preferred range is 15 to 50 parts.

Specific examples of such reactive silicone oil (component (a)) and reactive fluorine oil (component (b)) are shown below.

[Reactive silicone oil having a hydroxyl group]

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[Reactive silicone oil having amino group]

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[Reactive Silicone Oil Having Mercapto Group]

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[Reactive silicone oil having epoxy group]

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[Reactive silicone oil having a carboxyl group]

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[Reactive Silicone Oil Having Methacrylic Group]

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[Reactive Fluorine Oil Having Hydroxyl Group]

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[Reactive Fluorine Oil Having Amino Group]

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[Reactive Fluorine Oil Having Mercapto Group]

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[Reactive Fluorine Oil Having Epoxy Group]

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[Reactive Fluorine Oil Having Carboxyl Group]

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[Reactive Fluorine Oil Having Methacrylic Group]

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Among the reactive silicone oils (component a) and the reactive fluorine oils (component b) shown in the above specific examples, preferred are hydroxyl, amino, and mercapto groups because of their good reactivity. It has at least one, and particularly preferably has an amino group.

Next, in the present invention, in addition to the reactive silicone oil (component a) and the reactive fluorine oil (component b), the non-reactive silicone oil (component c) Fluorine oil (d component) can be blended. This non-reactive silicone oil or non-reactive fluorine oil does not have a reactive group for reaction and fixation in the fluoro rubber matrix. Fixed. This is because non-reactive silicone oils and the like are mixed in particles formed from the reactive silicone oils and the like, and both are bonded by a hydrophobic bond,
As a result, it is presumed that non-reactive silicone oil and the like are fixed in the fluororubber matrix. Therefore, even when the non-reactive silicone oil or the non-reactive fluorine oil is used, the adverse effect such as the generation of large aggregates does not occur if the amount is a predetermined amount.

The above non-reactive silicone oil (component (c))
Preferably has at least one organic group selected from the group consisting of an alkyl group, an aralkyl group, a higher alcohol ester group, and a polyether fluoroalkyl group. This is because the releasability is excellent.

Further, among the above non-reactive silicone oils, because of their excellent releasability and thermal stability,
Those having an average molecular weight in the range of 500 to 100,000 are preferable, and particularly preferably those having an average molecular weight of 2,000 to 5,000.
It is in the range of 0.

The total mixing ratio (c + d) of the non-reactive silicone oil (component c) and the non-reactive fluorine oil (component d) is usually set in the range of 10 to 100 parts with respect to 100 parts of the fluororubber. And preferably 2
The range is from 0 to 50 parts, particularly preferably from 30 to 40 parts.

Specific examples of such a non-reactive silicone oil are shown below.

[Non-reactive silicone oil having an alkyl group]

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[Non-reactive silicone oil having an aralkyl group]

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[Non-reactive silicone oil having higher alcohol ester group]

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[Non-reactive silicone oil having polyether fluoroalkyl group]

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Among the non-reactive silicone oils shown as specific examples, those having an alkyl group, a higher alcohol ester group, and a polyether fluoroalkyl group are preferred because of excellent releasability. Preferably, it has a higher alcohol ester group.

As the non-reactive fluorine oil, perfluoropolyether or the like is used.

The above-mentioned reactive silicone oil (component (a)), reactive fluorine oil (component (b)), non-reactive silicone oil (component (c)), non-reactive fluorine oil (d) In addition to the component, an ionic conductive agent can be blended for the purpose of imparting an appropriate volume electric resistance (10 ⁷ to 10 ¹² Ω · cm). The characteristic relating to the volume electric resistance is important, for example, as the characteristic of the outermost layer of the developing roll.

Examples of the ionic conductive agent include trimethyl octadecyl ammonium chloride, benzyl trimethyl ammonium chloride, trioctyl propylene ammonium chloride, trioctyl propyl ammonium bromide, trimethyl octadecyl ammonium perchlorate, tetrabutyl ammonium hydrogen sulfate, and tetrabutyl ammonium Quaternary ammonium compounds such as hydroxides and perchlorates, benzoates of these quaternary ammonium compounds,
Nitrite, sulfate, hydroxide and the like. These may be used alone or in combination of two or more. Above all,
It is preferable to use tetrabutylammonium hydrogen sulfate (TBAHS) or tetrabutylammonium hydroxide.

In addition to the above-mentioned ionic conductive agents, acid acceptors such as calcium hydroxide, magnesium oxide, calcium oxide, lead tan, litharge, and vulcanizing agents such as peroxide, bisphenol A, bisphenol AF, hexamethylenediamine, etc. Can be appropriately compounded as needed. As described later, the vulcanizing agent during the use of quotes I ing solution of the rubber composition of the present invention (coating front), it is preferable to blend in each case.

Next, a coating solution for the rubber composition of the present invention is prepared using the above-mentioned materials, for example, by the following method.

That is, first, the fluororubber is dissolved in the solvent. Examples of the solvent include ethyl acetate, methyl ethyl ketone, methanol, toluene, isopropyl alcohol, methyl cellosolve, and dimethylformamide. These may be used alone or in combination of two or more. Then, in the dissolved fluororubber, at least one of the reactive silicone oil (component a) and the reactive fluorine oil (component b), and if necessary, a non-reactive silicone oil (component c) and a non-reactive fluorine oil (D
Component) and other components. Then, stirring is performed under heating to increase the viscosity, and when the viscosity becomes constant, the stirring is stopped to prepare a coating solution of the rubber composition. The heating conditions are preferably in the range of 40 to 150 ° C , particularly preferably in the range of 50 to 80 ° C. In addition, at the time of this preparation, it is preferable that the vulcanizing agent is not blended but blended before use (before coating). The increase in viscosity during the stirring is presumed to be due to the finer particles (increase in the total surface area) of the reactive silicone oil and the like and the chemical bond between the reactive silicone oil and the like and the fluororubber molecules. The viscosity at which the above-mentioned constant value is obtained varies depending on the material used and the like, but is usually 2000 to 20000 cps, and preferably 3000 to 5000 cps.

[0053] In co <br/> Te I ring solution of the thus obtained rubber composition was formed from the fluororubber matrix (fluorine between the rubber molecules) reactive silicone oil (release agent) The particles are uniformly dispersed with a particle size of about 50 μm or less, and are fixed by reaction in the fluororubber matrix (between fluororubber molecules) (see FIG. 1). As a result,
As described above, the releasability is maintained for a long time without generating large aggregates such as the reactive silicone oil. In addition, the particle diameter of the above particles is preferably 0.1.
1 to 20 μm, particularly preferably 0.1 to 5 μm
It is.

The particle size distribution of the particles formed from the release agent is as follows. That is, when the cross-sectional areas of the above-mentioned particles having a particle size of 0.1 μm or more are measured, and the cross-sectional areas are sequentially accumulated in ascending order, 90% of the total accumulated cross-sectional area is obtained.
The particle size of the particle at the point where the cumulative cross-sectional area is
m or less. The above particle size refers to the maximum particle size. For example, the particle diameter of a particle having a circular cross-sectional shape is the particle diameter of the above-mentioned circular shape, and the particle diameter is the major diameter when the cross-sectional shape is an elliptical shape.

The above-mentioned “case in which the cross-sectional areas of the particles having a particle size of 0.1 μm or more are measured and sequentially accumulated in ascending order” means the following cases. That is, in the fluororubber composition, the cross-sectional area of the particles having a particle size of 0.1 μm or more is measured. This measurement can be performed, for example, by observing the fluororubber composition with a scanning electron microscope. The fluororubber composition may be in the state of a coating liquid or in the state of being the outermost layer of a roll. This observation does not need to be performed for the entire rubber composition, and may be partially performed by determining an observation location (sampling location). This sampling point is
The number is preferably 4 to 30, particularly preferably 20 to 30. The calculation of the cross-sectional area is performed according to the cross-sectional shape of the particles.For example, it is possible to calculate the area of each part by subdividing the particle cross-section and calculate the cross-sectional area of each particle by summing them. it can. Then, the cross-sectional areas are sequentially accumulated in ascending order, and the total accumulated cross-sectional area is calculated.

Then, with respect to the above "this total cumulative sectional area,
The particle size at the point where the cumulative cross-sectional area at a rate of 90% is 30 is
“μm or less” means the following. That is,
Derived the cumulative cross section of 90% of the above total cumulative cross section
I do. Then, the point of the cumulative cross-sectional area of this 90% ratio
Particle size (hereinafter referred to as “90% cumulative sectional area particle size”)
Ask for. An example of this is shown in the graph of FIG. This graph
In the figure, the vertical axis is the cumulative sectional area ratio (%), and the horizontal axis is
Particle size (μm) and particle cross-sectional area (μm ^Two)
You. As shown in the figure, the cross-sectional area of the particles
As the particle size (cross-sectional area) increases,
A curve with a larger cumulative area ratio is obtained. And points
As shown by the line, the particle at the point corresponding to the 90% cumulative cross-sectional area
The particle size is determined. And at this point the particle size of the particles
Is 30 μm or less, a roll according to the present invention.
Can be determined.

Next, an example in which the method for producing a roll of the present invention using this rubber composition coating solution is applied to a developing roll will be described.

The developing roll has a three-layer structure as shown in FIG. As shown in the drawing, the developing roll includes an innermost layer 11 and an intermediate layer 12 formed of an elastic body, and an outermost layer 13 formed of a fluororubber composition on the outer periphery of a shaft 10 such as a cored bar. I have.

The developing roll having the three-layer structure is manufactured as follows by the method of manufacturing the roll of the present invention. That is, first, a material for forming the innermost layer and the intermediate layer is prepared.

The components of the material for forming the innermost layer and the intermediate layer are not particularly limited, and those conventionally known can be used.

For example, as a material for forming the innermost layer, a material obtained by blending carbon black with ethylene propylene rubber (EPDM), styrene butadiene rubber (SBR), silicone rubber, polyurethane elastomer or the like can be used.

As the material for forming the intermediate layer, for example, EPDM, SBR, nitrile rubber, hydrogenated nitrile rubber, polyurethane elastomer, polyester, N
A mixture of methoxymethylated nylon and the like with a conductive agent such as carbon black, metal oxide, or quaternary ammonium salt.

As a method of preparing the material for forming the innermost layer and the intermediate layer, a conventionally known method is applied. To give an example, first, the innermost layer forming material (compound form)
Is prepared by kneading the above components with a kneader such as a kneader. The material for forming the intermediate layer (coating liquid)
Is prepared by kneading with a ball mill or a roll, adding a solvent to the mixture, and mixing and stirring.

Next, an innermost layer and an intermediate layer are formed on the outer periphery of the shaft body by a conventional method, and a roll base is manufactured. For example, as shown in FIG.
Then, a compound-like innermost layer forming material is poured into the cylindrical mold 16, and the upper lid 17 is fitted over the cylindrical mold 16. In this state, the entire roll mold is heated (vulcanization treatment, conditions: 150 to
(200 ° C. × 20 to 40 minutes) to form the innermost layer. Next, the shaft on which the innermost layer is formed is released from the mold, and the residue of the vulcanizing agent is removed by evaporation, if necessary. Then, an intermediate layer forming material (coating liquid) is applied to the outer peripheral surface of the innermost layer, and dried and heated (vulcanization, conditions: 120 to 200 ° C. × 1).
(0 to 30 minutes) to form an intermediate layer. The above coating is
Conventionally known coating methods such as a dipping method, a spray method, and a roll coating method can be applied. In this way, a roll base having the innermost layer and the intermediate layer formed on the outer periphery of the shaft body is manufactured.

On the other hand, a vulcanizing agent is blended with the rubber composition (coating liquid) of the present invention. Then, the rubber composition is applied to the outer peripheral surface of the intermediate layer of the roll base. The coating method is not particularly limited, de I mappings method, a spray method, a conventional method is applied, such as roll coating.
Then, after coating, by performing drying and heat treatment (vulcanization treatment, conditions: 150 to 200 ° C. × 20 to 40 minutes), the solvent in the rubber composition is removed by evaporation and the fluorine rubber component is crosslinked. . In this way, a developing roll having a three-layer structure as shown in FIG. 6 can be manufactured. In this developing roll, the thickness of each layer is appropriately determined, but the thickness of the innermost layer is preferably set in the range of 2 to 10 mm, and particularly preferably 3 to 6 mm. The thickness of the intermediate layer is preferably set in the range of 3 to 90 μm, and particularly preferably 5 to 15 μm. The thickness of the outermost layer is preferably from 20 to 100 μm, particularly preferably from 30 to 70 μm.

As described above, the developing roll can be produced by the method for producing the roll of the present invention, but the present invention is not limited to this. That is, the manufacturing method of the roll of the present invention is:
The present invention can be applied to a roll of a type in which the roll surface is in direct contact with the toner since excellent roll release properties can be imparted to the roll surface for a long period of time. Examples of such a roll include a fixing roll.

[0067]

As is evident from the foregoing description, the roll of the process of the present invention is to use quotes I ing liquid special fluorine rubber. Cote I ring solution of the specific fluorine rubber composition are those obtained by the above-mentioned special manufacturing method. Therefore, in the coating solution of the fluororubber composition, particles formed from the reactive silicone oil or the like are uniformly dispersed, the particle size of the particles is about 50 μm or less, and The reaction is fixed. Then, by applying the coating liquid of the special fluororubber composition to the roll base to form the outermost layer, a desired roll can be obtained. And, for example, if the roll manufacturing method of the present invention is applied to a developing roll,
It is possible to prevent the generation of large aggregates such as silicone oil as a toner release agent and the exudation to the roll surface, which are problems in the conventional developing roll. As a result, with this developing roll, occurrence of toner filming is prevented, and a high-quality copied image can be obtained for a long period of time.

Next, examples will be described together with comparative examples.

First, prior to the examples and comparative examples, a core metal (diameter: 10 mm, made of SUS304) serving as a shaft, a material obtained by adding carbon black to liquid silicone rubber as an innermost layer forming material, and a material obtained by adding an intermediate layer forming material What prepared carbon black added to hydrogenated nitrile rubber was prepared.

Then, the innermost layer and the intermediate layer were formed on the outer periphery of the shaft according to the above-mentioned method, and a roll base was produced.

[0071]

Examples 1 to 7 and Comparative Examples 1 to 4 An outermost layer was formed on the outer peripheral surface of the above-mentioned roll substrate by the above-mentioned method. That is, the materials shown in the following Tables 1 to 3 were blended in the proportions shown in the same table, and a coating solution of a fluororubber composition was prepared according to the method described above. Using this, an outermost layer was formed on the outer peripheral surface of the roll base by the above-described method (coating method: roll coating method), and a target developing roll was produced. The thickness of the innermost layer of this developing roll is 5 mm
The thickness of the intermediate layer is 10 μm, and the thickness of the outermost layer is 50 μm.

With respect to the developing rolls of Examples 1 to 7 and Comparative Examples 1 to 4 obtained as described above, evaluation of copied images and occurrence of toner filming were examined by the following methods. The results are also shown in Tables 1 to 3 below. In the same table, the average particle diameter and the 90% cumulative sectional area particle diameter of the particles are also shown. The measurement of the 90% cumulative sectional area particle size was performed by the method described below.

[Evaluation of Copy Image] The developing roll was incorporated in an electrophotographic copying machine, and copying was actually performed. Then, the image quality of the copied image was visually evaluated at the beginning of copying and after copying 30,000 sheets. That is, characters are printed, and there is no problem with the copied image.
When the fine line was clearly copied, the result was indicated by ○, and when the thin line was fogged or the like, the result was indicated by ×. Note that blurring refers to a thing in which a thin line is interrupted, and fogging refers to a thing in which toner has flown to a place where there is no image. When toner filming occurred, evaluation was made separately for a portion where toner filming occurred and a portion where toner filming did not occur.

[Toner Filming] The portion where the toner is thickly adhered to the surface of the developing roll has poor chargeability and causes a defect in a copied image. Specifically, if a part of the toner component adheres to the surface of the developing roll with a thickness of 1 μm or more, the image is significantly deteriorated. Therefore, when the toner adhesion was 1 μm or more, it was determined that toner filming had occurred.

[90% Cumulative Cross-sectional Area Particle Size] As shown in FIG. 9A, two cuts are made in the elastic portion (the innermost layer, the intermediate layer, and the outermost layer) of the developing roll 20 at right angles to the axial direction. A sample 20a as shown in FIG. 3B was prepared. Then, as shown in the cross-sectional view of the sample 20a in FIG.
Observation was performed with a scanning electron microscope (S-4100, manufactured by Horiba, Ltd.). According to the procedure described above, 90% using an image processor (Spica II, manufactured by Nippon Avionics)
The cumulative cross section particle size was determined automatically.

[0076]

[Table 1]

[0077]

[Table 2]

[0078]

[Table 3]

From the above Tables 1 and 2, in Examples 1 to 7, the particles of the reactive silicone oil and the like had a 90% cumulative sectional area particle size of 30 μm or less. In each of the developing rolls of Examples 1 to 7, there was no problem in the copied image, fine lines were clearly copied, and toner filming did not occur. In contrast, from Table 3 above, Comparative Example 1
In Nos. To 4, the 90% cumulative sectional area particle size of the particles of the reactive silicone oil or the like exceeded 30 μm. In the developing rolls of Comparative Examples 1 to 4, toner filming occurred, and the copied image was poor in this portion.

Next, the state of the particles formed from the reactive silicone oil in the outermost layer of the developing rolls of Example 1 and Comparative Example 1 was examined by using the above-mentioned scanning electron microscope. Shown in the photo.

FIG. 2 is a photograph (magnification: 10,000 times) showing the state of the surface of the outermost layer of the developing roll of Example 1. FIG.
It is a photograph (10,000 times magnification) which shows the state of the inside of the same outermost layer (axial section). FIG. 4 is a photograph (magnification: 10,000 times) showing the state of the surface of the outermost layer of the developing roll of Comparative Example 1.
FIG. 5 is a photograph (magnification: 10,000 times) showing a state inside the same outermost layer (cross section in the axial direction). From the photographs of FIGS. 2 and 3,
In the developing roll of Example 1, the particles formed from the reactive silicone oil had a very small particle size of about 1 μm or less, and were found to be uniformly dispersed in the fluororubber matrix. On the other hand, from the photographs of FIGS. 4 and 5,
In the developing roll of Comparative Example 1, it can be seen that the particle size of the particles formed from the reactive silicone oil is large.

Comprehensively judging from the results of these electron microscopic observations and the results (toner filming) in Tables 1 to 3, the particles formed from the reactive silicone oil dispersed in the fluororubber matrix were Since the 90% cumulative cross-sectional area particle diameter is 30 μm or less and is fixed by reaction in the fluororubber matrix, it can be said that toner filming was prevented from occurring in the developing roll of the example.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a microscopic structure of a fluororubber composition of the present invention.

FIG. 2 is a photograph showing a structure of particles formed from a reactive silicone oil on the surface of the outermost layer of a developing roll according to an embodiment of the present invention.

FIG. 3 is a photograph showing a structure of particles formed from a reactive silicone oil inside an outermost layer of a developing roll according to an embodiment of the present invention.

FIG. 4 is a photograph showing the structure of particles formed from a reactive silicone oil on the surface of the outermost layer of a conventional developing roll.

FIG. 5 is a photograph showing the structure of particles formed from a reactive silicone oil inside the outermost layer of a conventional developing roll.

FIG. 6 is a cross-sectional view illustrating a structure of a developing roll.

FIG. 7 is a cross-sectional view illustrating a method of manufacturing a developing roll.

FIG. 8 is a graph showing the relationship between the particle size of the particles and the cumulative cross-sectional area ratio of the particles.

9A is a perspective view showing a state in which a cut is made in the developing roll, FIG. 9B is a perspective view of a sample cut from the developing roll, and FIG. 9C is a cross-sectional view of the sample. .

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Akihiko Kaji Komaki City, Aichi Prefecture, Ogai Kita-gaiyama, Gezu 3600 Tokai Rubber Industries Co., Ltd. (56) References JP-A-3-284780 (JP, A) JP Hei 3-285934 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 15/08 501 G03G 15/09-15/09 101 G03G 15/16 103 G03G 15/20 103 F16C 13/00

Claims (5)

(57) [Claims] 1. A method for producing a roll in which a coating solution of a fluororubber composition is applied to an outer peripheral surface of a roll substrate and then vulcanized to form a fluororubber outermost layer, wherein the fluororubber composition is A method for producing a roll, comprising using the following (A) as a coating liquid. (A) At least one of a reactive silicone oil and a reactive fluorine oil is blended with a fluororubber dissolved in a solvent, and the viscosity is increased by stirring under heating, and the stirring is stopped when the viscosity becomes constant. A coating solution of the fluororubber composition prepared by the above method. 2. The reactive silicone oil has at least one reactive group selected from the group consisting of a hydroxyl group, an amino group, a mercapto group, an epoxy group, a carboxyl group, and a methacryl group,
2. The roll according to claim 1, wherein the reactive fluorine oil is a reactive fluorine oil having at least one reactive group selected from the group consisting of a hydroxyl group, an amino group, a mercapto group, an epoxy group, a carboxyl group, and a methacryl group. Manufacturing method. 3. The method for producing a roll according to claim 1, wherein the heating condition is in a range of 40 to 150 ° C. 4. The roll according to claim 1, wherein the average molecular weight of the reactive silicone oil is 300 to 150,000, and the average molecular weight of the reactive fluorine oil is 200 to 20,000. Recipe. 5. The fluorine-containing rubber according to claim 1, wherein the total amount of said reactive silicone oil and said reactive fluorine oil is 10%.
The amount is 0.5 to 100 parts by weight with respect to 0 parts by weight.
The method for producing a roll according to any one of claims 4 to 4.