JP2013025262A - Fixing member, fixing device, and image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fixing member that has excellent toner releasability, and is less likely to have an offset.SOLUTION: A fixing member is used for fixing a toner image, and has an elastic layer on the outermost layer. The elastic layer contains rubber and a heterocyclic compound having a triazine structure.

Description

  The present invention relates to a fixing member, a fixing device, and an image forming apparatus.

  2. Description of the Related Art An electrophotographic image forming apparatus such as a copying machine or a printer includes a fixing device that fixes a toner image transferred to a recording medium. The fixing device includes a heating unit that heats the toner image on the recording medium, a fixing member that fixes the toner image on the recording medium, and a pressure member that forms a fixing nip with the fixing member. Heat and press to fix on the recording medium.

  As the fixing member, a belt shape or a roller shape is known, and an elastic layer and / or a release layer made of silicone rubber or the like on a metal roller serving as a base or a seamless belt made of resin or metal. What provided is used.

  However, since the fixing member comes into contact with the heated and melted toner image, a part of the toner image may be transferred to the surface of the fixing member. Another problem is that the recording medium is wound around the fixing member by the toner under melting during fixing. Therefore, techniques for improving the releasability between the fixing member and the toner and the separability of the fixed image have been developed.

  For example, Patent Document 1 discloses a heat roller type fixing member having a release resin layer having a benzoguanamine / formaldehyde condensate dispersed therein on the surface.

  However, the release layer of Patent Document 1 has a higher hardness than the release layer made of silicone rubber or the like, and hardly follows the irregularities on the surface of the recording medium when fixing the toner to the recording medium. Therefore, there is a problem that the toner is easily offset at a place where the fixing is insufficient.

  Accordingly, an object of the present invention is to provide a fixing member that is excellent in toner releasability and hardly offsets.

According to the present invention,
A fixing member used for fixing a toner image,
The fixing member has an elastic layer as an outermost layer,
A fixing member is provided in which the elastic layer includes a rubber and a heterocyclic compound having a triazine structure.

  According to the present invention, it is possible to provide a fixing member that is excellent in toner releasability and hardly offsets.

FIG. 1 is a view for explaining a fixing member of the present invention, and is a schematic view of an example of a fixing roller. FIG. 2 is a view for explaining the elastic member of the present invention, and is a schematic view of another example of the fixing roller. FIG. 3 is a schematic view showing an example of a roller fixing device having the fixing member of the present invention. FIG. 4 is a schematic view showing an example of an image forming apparatus having the fixing member of the present invention.

  The present invention will be specifically described with reference to the drawings. In addition, this invention is not limited to the following embodiment, It can change and / or improve within the range of the objective of this invention.

[Fixing member]
≪Configuration of fixing member≫
FIG. 1 is a diagram for explaining a fixing member of the present invention, and shows a schematic diagram of an example of a fixing roller.

  In FIG. 1, the fixing roller 10 has an elastic layer 12 including a rubber and a heterocyclic compound having a triazine structure in a molecule described in detail below on a core metal (base material) 11.

  Although it does not restrict | limit especially as a material which can be used for the metal core 11, It is preferable to use metals, such as aluminum, stainless steel, brass, copper, nickel, glass material, ceramics.

  The rubber contained in the elastic layer 12 is not particularly limited, but preferably contains a rubber selected from the group consisting of silicone rubber, fluorocarbon siloxane rubber and fluorosilicone rubber. These rubbers may be used alone or in combination of two or more.

  The silicone rubber is not particularly limited as long as it is a silicone rubber having an organosiloxane structure. For example, the general formula (1)

（式中、Ｒ_１、Ｒ_２は脂肪族不飽和結合を有さず、置換基により置換されていても良い、一価炭化水素基である。また、Ｒ_１及びＲ_２は、互いに同一の基であっても良いし、異なる基であっても良い。さらに、Ｒ_１及びＲ_２は、炭素数が１〜８であることが好ましい。具体的には、アルキル基、シクロアルキル基、アリール基などが挙げられるが、メチル基、エチル基、フェニル基が好ましい。）
で表される構成単位を有するシリコーンゴムを好ましく使用することができる。

(In the formula, R ₁ and R ₂ are monovalent hydrocarbon groups which do not have an aliphatic unsaturated bond and may be substituted with a substituent. Further, R ₁ and R ₂ are the same as each other. R ₁ and R ₂ preferably have 1 to 8 carbon atoms, specifically, an alkyl group, a cycloalkyl group, or an aryl group. A methyl group, an ethyl group, and a phenyl group are preferable.
The silicone rubber which has a structural unit represented by can be used preferably.

  Examples of commercially available silicone rubber compounds include KE1950-30 (manufactured by Shin-Etsu Chemical Co., Ltd.) and DY35-2083 (manufactured by Dow Corning Toray).

  The fluorocarbon siloxane rubber is not particularly limited as long as it has a fluorocarbon siloxane structural unit. For example, the general formula (2)

（式中、Ｒ_３は、置換基により置換されていても良い、炭素数が１〜８のアルキル基、シクロアルキル基又はアリール基であり、ａ及びｅは、それぞれ独立に、０又は１であり、ｂ及びｄは、それぞれ独立に、１〜４の整数であり、ｃは０〜８の整数であることが好ましい。）
で表される構成単位を有するフルオロカーボンシロキサンゴムを好ましく使用することができる。

(In the formula, R ₃ is an alkyl group having 1 to 8 carbon atoms, a cycloalkyl group, or an aryl group, which may be substituted with a substituent, and a and e are each independently 0 or 1; Yes, b and d are each independently an integer of 1 to 4, and c is preferably an integer of 0 to 8.)
The fluorocarbon siloxane rubber which has a structural unit represented by these can be used preferably.

  Examples of commercially available compounds of fluorocarbon siloxane rubber include SIFELR3400 (manufactured by Shin-Etsu Chemical Co., Ltd.).

  The fluorosilicone rubber is not particularly limited as long as it is a fluorosilicone rubber having a fluoroorganosiloxane structural unit. For example, the general formula (3)

（式中、ｎは０〜２０の整数であることが好ましい。）
で表される構成単位を有するフロロシリコーンゴムを好ましく使用することができる。

(In the formula, n is preferably an integer of 0 to 20.)
Fluorosilicone rubber having a structural unit represented by can be preferably used.

  Examples of commercially available fluorosilicone rubber compounds include X36-420 (manufactured by Shin-Etsu Chemical Co., Ltd.), FSE7540, FSL7641 (manufactured by Momentive Performance Materials), SE-1541-U (manufactured by Toray Dow Corning), and the like. .

  Next, the heterocyclic compound having a triazine structure in the molecule will be described in detail.

  A heterocyclic compound (sometimes referred to as a heterocyclic compound) refers to a compound in which atoms other than carbon are contained in the cyclic structure among organic compounds having a cyclic structure. Further, it is usually classified into an aromatic heterocyclic ring having an unsaturated bond in the cyclic structure and having aromaticity, and the other. Nitrogen, oxygen, sulfur, etc. are mentioned as atoms other than carbon contained in a cyclic structure.

  The heterocyclic compound that can be used in the present invention is not particularly limited as long as it has a triazine structure in the molecule. For example, 1,3,5-triazine, benzoguanamine, melamine or derivatives or reactants or oligomers thereof. A polymer or the like can be preferably used. Among these, a melamine resin which is a condensate of melamine and formaldehyde can be particularly preferably used.

  The heterocyclic compound having a triazine structure may be contained in the fixing member as powder and / or fine particles, or may be contained as composite fine particles with an inorganic substance such as silica.

  The shape and particle size of the heterocyclic compound fine particles or composite fine particles having a triazine structure are not particularly limited as long as the processability (viscosity, etc.) and surface properties (roughness, etc.) of the fixing member are not impaired. Usually, it is preferable that the shape is a spherical shape rather than an indefinite shape because it is uniformly dispersed in the rubber and the surface roughness becomes uniform. Moreover, as a particle size, it is preferable that it is 100 nm-10 micrometers. When the particle size is smaller than 100 nm, the viscosity of the rubber increases and the processability may deteriorate. On the other hand, when the particle size is larger than 10 μm, the surface roughness may increase.

  Further, the content of the fine particles or the composite fine particles of the heterocyclic compound having a triazine structure is preferably 1 to 50 parts by mass, more preferably 5 to 20 parts by mass with respect to 100 parts by mass of the rubber. preferable. When the content of the fine particles of the heterocyclic compound having a triazine structure or the composite fine particles is less than 1 part by mass with respect to 100 parts by mass of the rubber, the effect of adding the heterocyclic compound may not be obtained. On the other hand, when the content of the heterocyclic compound exceeds 50 parts by mass, the increase in viscosity due to the addition of the heterocyclic compound increases, and the surface properties of the fixing member may be impaired.

≪How to create a fixing member≫
The method for forming the elastic layer 12 on the core metal 11 is not particularly limited, but an example is given below. A cored bar on which a primer layer is formed is placed inside the mold using a silane coupling agent, a silicone adhesive, or the like. One or more rubber precursors selected from the group consisting of silicone rubber, fluorocarbon siloxane rubber and fluorosilicone rubber, to which a heterocyclic compound having a triazine structure is added, are heated.

  Moreover, the rubber contained in the elastic layer 12 may contain other components. For example, additives such as fillers, reinforcing agents, conductivity control agents, anti-aging agents, colorants, plasticizers, waxes and oils may be included.

  FIG. 2 is a view for explaining the elastic member of the present invention, and shows a schematic view of another example of the fixing roller. The fixing roller 10 has the same configuration as that of FIG. 1 except that an intermediate layer 13 is formed between the core metal 11 and the elastic layer 12. By forming the intermediate layer 13, the thickness of the elastic layer 12 can be reduced.

  The material that can be used for the intermediate layer 13 is not particularly limited as long as it is a heat-resistant rubber.

  In FIGS. 1 and 2, a roller-type member is exemplified as an example of the fixing member. However, in the present invention, an elastic layer containing a rubber and a heterocyclic compound having a triazine structure in the molecule is formed. However, the present invention is not limited to this. For example, a fixing member having another shape such as a seamless belt type, a sheet type, or a film type may be used.

  The material constituting the base material of the seamless belt-shaped fixing member is not particularly limited, and examples thereof include resins such as polyimide, polyamide, and polyamideimide, and metals such as nickel and stainless steel.

  The method of forming the elastic layer 12 on the base material (core metal) of the seamless belt-shaped fixing member is not particularly limited. Here is an example. Using a silane coupling agent, a silicone-based adhesive, or the like, the base material on which the primer layer is formed is placed in a mold while being fixed to a mandrel. A precursor of one or more rubbers selected from the group consisting of silicone rubber, fluorocarbon siloxane rubber and fluorosilicone rubber to which a heterocyclic compound having a triazine structure is added is injected and heated.

  Further, in the present specification, the fixing member is described as an example of the elastic member. However, the present invention is not limited to this, and can be applied to, for example, a charging member, a developing member, and a transfer member. When the present invention is applied to the charging member and the developing member, nitrile rubber, epichlorohydrin rubber, or the like is preferably used as the rubber contained in the elastic layer. When applied to a transfer member, epichlorohydrin rubber, silicone rubber, urethane rubber or the like is preferably used.

[Fixing device]
FIG. 3 is a schematic view showing an example of a roller fixing device having the fixing member of the present invention.

  The fixing device 100 includes a fixing roller 10 and a pressure roller 20. The fixing roller 10 is an example of the fixing member of the present invention, and an elastic layer is laminated on the core metal 11. The fixing roller 10 includes a halogen heater 15 as a heating unit. A temperature sensor 16 is provided on the surface of the elastic layer 12.

  In the pressure roller 20, an elastic layer 22 including a heat-resistant rubber and a release layer 23 are sequentially laminated on a cored bar 21. The pressure roller 20 is pressed against the fixing roller 10 to form a nip portion. At this time, when the recording medium P to which the toner T adheres passes through the nip portion, the toner T adhering to the recording medium P is heated and softened by the fixing roller 10 and is pressurized, It is fixed on the recording medium P.

[Image forming apparatus]
FIG. 4 is a schematic view showing an example of an image forming apparatus having the fixing member of the present invention.

  The image forming apparatus 1000 includes a fixing device 100 as an example of the present invention, a photosensitive drum 200, a charging roller 300, a developing roller 400, a transfer roller 500, and a cleaning device 600. The charging roller 300 contacts and charges the photosensitive drum 200, and the developing roller 400 develops the electrostatic latent image formed on the photosensitive drum 200 with toner to form toner. The transfer roller 500 transfers the toner image formed on the photosensitive drum 200 to the recording medium P. The cleaning device 600 cleans the photosensitive drum 200 to which the toner image is transferred.

  The image forming apparatus 1000 also includes an exposure apparatus (not shown) that forms an electrostatic latent image by irradiating the charged photosensitive drum 200 with laser light L. Further, the image forming apparatus 1000 includes a power source 310 that applies a DC voltage to the charging roller 300 and a surface potential meter 210 that measures the surface potential of the photosensitive drum 200.

  Next, a method for forming an image using the image forming apparatus 1000 will be described. First, the photosensitive layer (not shown) formed on the photosensitive drum 200 is uniformly charged using the charging roller 300 while rotating the photosensitive drum 200. Next, an electrostatic latent image is formed by irradiating the charged photosensitive layer with laser light L using an exposure apparatus. Further, using the developing roller 400, toner is attached to the electrostatic latent image formed on the photosensitive layer and developed to form a toner image. Next, the toner image formed on the photosensitive layer is transferred to the recording medium P using the transfer roller 500. Then, the toner image transferred to the recording medium P is fixed using the fixing device 100.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by an Example. In addition, a part means a mass part.

[Example 1]
On the surface of a polyimide seamless belt having an inner diameter of 60 mm, a width of 400 mm, and a thickness of 0.1 mm, a silicone rubber pliers (DY39-067; manufactured by Dow Corning Toray) is 0.5 μm in thickness. It was applied as follows. Then, it was dried at room temperature for 30 minutes and subsequently at 150 ° C. for 30 minutes.

  The obtained seamless belt was fixed to a mandrel, and a silicone rubber compound (DY35-2083; manufactured by Toray Dow Corning Co., Ltd.) added with spherical fine particles of melamine / formaldehyde condensate (Eposter RS12; manufactured by Nippon Shokubai Co., Ltd.) was injected. . At this time, 5 parts of spherical fine particles of the melamine / formaldehyde condensate were added to 100 parts of the silicone rubber compound. Next, after heating at 150 ° C. for 10 minutes, the seamless belt was removed from the mold and heated at 200 ° C. for 4 hours to form a male layer to obtain a fixing belt.

[Example 2]
Instead of the melamine / formaldehyde condensate used in Example 1, the same as Example 1 except that 5 parts of composite fine particles of melamine / formaldehyde condensate and silica (Optobeads R500S; manufactured by Nissan Chemical Industries, Ltd.) were used. Through this process, a fixing belt was obtained.

[Example 3]
Instead of the silicone rubber primer and the silicone rubber compound used in Example 2, a fluorine-containing resin primer (Primer Z; manufactured by Shin-Etsu Chemical Co., Ltd.) and a fluorocarbon siloxane rubber compound (SIFELR 3400; manufactured by Shin-Etsu Chemical Co., Ltd.), respectively. A fixing belt was obtained by the same process as in Example 2 except that it was used.

[Example 4]
A fixing belt was obtained in the same manner as in Example 2, except that fluorosilicone rubber (FSL7641; manufactured by Momentive Performance Materials) was used instead of the fluorocarbonsiloxane rubber compound used in Example 2.

[Comparative Example 1]
A fixing belt was obtained by the same process as in Example 1 except that acrylic fine particles (Lyosphere RSP-3015D; manufactured by Toyo Ink Co., Ltd.) were used instead of the melamine / formaldehyde condensate used in Example 1.

[Comparative Example 2]
A fixing belt was obtained in the same manner as in Example 1 except that spherical amorphous silica (Seahoster RKE-S250; manufactured by Nippon Shokubai Co., Ltd.) was used instead of the melamine / formaldehyde condensate used in Example 1.

[Evaluation]
≪Fixing member surface tack≫
The surface tack of the fixing belts obtained in the examples and comparative examples was measured using a tacking tester (TAC2; manufactured by Reska).

The measurement conditions are
Temperature: 25 ° C (room temperature)
Probe: Stainless steel, diameter 8mm
Load: 200gf
Pressing speed: 120 mm / min
Lifting speed: 600mm / min
It was.

  Table 1 shows the measurement results of the tacking test.

表１より、実施例で得られた定着ベルトは、比較例で得られた定着ベルトに比べ、タックが小さいことがわかる。

From Table 1, it can be seen that the fixing belt obtained in the example has a smaller tack than the fixing belt obtained in the comparative example.

≪Toner releasability≫
Next, the toner releasability of the fixing belts obtained in the examples and comparative examples was evaluated.

Evaluation conditions are
Copy machine: RICOH imagio MP C2500 (manufactured by Ricoh Co., Ltd.)
Copy original: solid image (cyan, 600 dpi, image area ratio 100%)
Copy mode: Full color, single side Recording medium: Recycled paper, My recycled paper 100, A4 size (manufactured by Ricoh Co., Ltd.)
Evaluation interval: Every 500 sheets up to 5000 copies Toner: imagio spot toner C3000 (Cyan, manufactured by Ricoh Co., Ltd.)
It was.

  Under the above evaluation conditions, the fixing belts obtained in Examples and Comparative Examples were replaced with a fixing belt of RICOH imagio MP C2500 to perform copying.

  When the number of copies reached the evaluation condition, the presence or absence of toner (offset) transferred from the surface of the fixing member to the paper through the white paper was visually confirmed. Further, the surface of the fixing member was visually observed to confirm the presence or absence of toner adhesion.

  In the determination of the releasability of the toner, the case where no toner offset or sticking occurred was evaluated as ◯, and the case where either one occurred occurred as x.

  Table 2 shows the evaluation results of the releasability of the toner.

表２より、実施例で得られた定着ベルトを用いることにより、トナーのオフセットが発生しないことがわかる。一方、比較例１の定着ベルトでは、ベタ画像の複写を開始して間もなくオフセットが発生した。また、比較例２の定着ベルトでは、複写枚数が１０００枚目のベタ画像に若干のオフセットが発生し、１５００枚目でオフセットに起因する画像の乱れが発生した。

It can be seen from Table 2 that toner offset does not occur by using the fixing belt obtained in the example. On the other hand, in the fixing belt of Comparative Example 1, an offset occurred soon after the solid image was copied. Further, in the fixing belt of Comparative Example 2, a slight offset occurred in the solid image having the number of copies of 1000, and the image disturbance due to the offset occurred in the 1500th sheet.

DESCRIPTION OF SYMBOLS 10 Fixing roller 11 Core metal 12 Elastic layer 13 Intermediate layer 15 Halogen heater 20 Pressure roller 21 Core metal 22 Elastic layer 23 Release layer 100 Fixing device 200 Photoreceptor drum 210 Surface potential meter 300 Charging roller 310 Power supply 400 Developer roller 500 Transfer Roller 600 Cleaning device 1000 Image forming device L Laser light T Toner P Recording medium

JP-A-63-137262

Claims (6)

A fixing member used for fixing a toner image,
The fixing member has an elastic layer as an outermost layer,
The elastic member includes a fixing member including rubber and a heterocyclic compound having a triazine structure.   The fixing member according to claim 1, wherein the heterocyclic compound having a triazine structure is a melamine resin.   The fixing member according to claim 1, wherein the elastic layer further includes silica.   The fixing member according to claim 1, wherein the rubber includes a rubber selected from the group consisting of silicone rubber, fluorocarbon siloxane rubber, and fluorosilicone rubber.   A fixing device including the fixing member according to claim 1. A photoreceptor,
A charging device for charging the photoreceptor;
An exposure device that exposes the charged photoreceptor to form an electrostatic latent image;
A developing device for developing the electrostatic latent image formed on the photoreceptor with toner to form a toner image;
A transfer device for transferring the toner image formed on the photoreceptor to a recording medium;
A fixing device according to claim 5;
An image forming apparatus.

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