JP2006259529A - Image forming method and image forming apparatus using method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To use a fixing member having excellent flexing resistance and surface smoothness, and to provide a toner having excellent cleanability, low-temperature fixability, offset resistance and electrostatic charge quantity distribution. <P>SOLUTION: The fixing member whose outermost layer is composed of different fluorine-based resins, and the toner obtained by at least dissolving or dispersing a compound (A) having active hydrogen group, a compound (B) having an area reactable with the compound (A), a colorant, and a release agent, into an organic solvent, by dispersing the solution or dispersion in an aqueous medium. and by reacting a polymer having an area reactable with a compound having the active hydrogen group therewith or while continuing the reaction, then by removing the organic solvent, thereafter by cleaning and drying the mixture, are used. The compound (A) is a general formula: H2N-R-NH-R'. where R is represented by saturated alkyl and C2 to C6, and R' by saturated or unsaturated alkyl and C8 to C24. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image forming method, and more specifically, bending resistance and surface smoothness for revealing an electrostatic image formed on the surface of a photoreceptor in electrophotography, electrostatic recording, electrostatic printing, and the like. The present invention relates to an image forming method using an excellent fixing member and an electrophotographic toner excellent in cleaning property, low temperature fixing property, offset resistance, and charge amount distribution, and an image forming apparatus employing the method.

  Conventionally, in electrophotographic image formation, a latent image by an electrostatic charge is formed on an image carrier such as a photoconductive substance, and charged toner particles are attached to the electrostatic latent image to form a visible image. Forming. The visible image formed by the toner is finally transferred to a transfer medium such as paper, and then fixed to the transfer medium by heat, pressure, solvent gas, or the like, and becomes an output image.

  These image forming methods include a so-called two-component development method in which toner particles for charging a toner image are charged, friction charging by stirring and mixing of toner particles and carrier particles, and without using carrier particles. This is roughly divided into a so-called one-component development system in which charge is imparted to toner particles. In addition, the one-component development method is classified into a magnetic one-component development method and a non-magnetic one-component development method depending on whether or not a magnetic force is used for holding toner particles on the developing roller.

  On the other hand, in general, in terms of heat efficiency, simplicity of a fixing mechanism, and manufacturing cost of a fixing member, a fixing member such as a fixing roller or a fixing belt is directly pressed against an unfixed image to heat the toner to melt the paper. A method of fixing to an image carrier such as a hot pressure fixing method is preferably employed.

  In particular, in recent years, a fixing mechanism using a belt-shaped heat transfer medium (hereinafter referred to as belt fixing) has been widely used for the purpose of energy saving and apparatus miniaturization.

  In such belt fixing, the contact time with the surface of the toner can be lengthened especially during fixing, and fixing at a lower temperature is possible. On the other hand, melting of the toner is further promoted so that the toner adheres to the surface of the belt. A so-called offset phenomenon is likely to occur. In particular, in color toners, an appropriate gloss is required to provide sufficient transparency and a high quality feeling, and the molecular weight of the binder resin is sharpened and sharp melt characteristics are required. Thereby, melting of the toner is promoted at the time of fixing, and an offset phenomenon is likely to occur.

  As the fixing belt, an endless or endless belt made of heat-resistant resin is often used, and a problem associated with this is improvement of mechanical durability.

  In addition, the toner external additive and other components may adhere to the belt-like heat transfer medium, resulting in belt wear and scratches, hot offset, and even the belt itself tearing. .

  In order to solve the above problems, various proposals have been made so far in terms of a fixing mechanism and an electrophotographic toner.

For example, the fixing device includes a fixing roller having a small belt curvature and a fixing belt which is stretched between a heating roller and endlessly moving while being heated by the heating roller. The toner image on the material is heat-fixed. (For example, refer to Patent Document 1.) This fixing belt is generally composed of a heat-resistant resin such as polyimide, a metal base, a heat-resistant rubber, an elastic layer made of an elastomer, a release layer made of a fluororesin (the outermost layer). ). The release layer made of the fluororesin is formed by coating a fluororesin tube formed by extrusion molding on the elastic layer, and then heating and melting (hereinafter, fired) the fluororesin. Moreover, after applying fluororesin particles to the elastic layer by spraying or the like, the fluororesin is fired to form a release layer. Thus, by forming the release layer with a fluororesin, a fixing belt having excellent release properties and heat resistance can be obtained. However, since the fluororesin is poor in flexibility, if it is stretched between a fixing roller having a small belt curvature and a heating roller and used for a long time, the release layer will crack, and sufficient belt durability can be obtained. I could not. Various proposals have been made to solve such problems. For example, Patent Document 2 discloses a fixing belt in which the release layer is made of a fluororesin having a melt viscosity (melt mass flow rate (hereinafter abbreviated as MFR)) of 3 or less and cracks are not generated even when used for a long time. Is described. (For example, see Patent Document 2.)
However, the low melting type fluororesin having a low MFR has poor fluidity at the time of melting, so that the fluororesin particles melted at the time of firing do not flow, resulting in a fixing belt having unevenness on the surface and poor smoothness. There was a bug. When image fixing is performed using such a fixing belt having poor surface smoothness, there is a problem that uneven gloss occurs in the fixed image on the transfer paper and causes deterioration of the image. This problem causes not only the fixing belt but also the fixing roller.

  It is also known to add a fixing release material such as wax to the toner to prevent offset during fixing. However, if the characteristics of the wax and the state of dispersion in the toner are inappropriate, development is possible. With long-term use in the unit, phenomena such as wax detachment from the toner surface or exudation occur, and in the case of two-component developers, the carrier surface is contaminated. In the case of a one-component developer, the toner is often fused to a developing roller or a blade for thinning the toner, thereby hindering uniform development of the toner. Therefore, from the viewpoint of development, it is preferable that the addition of wax is as small as possible.

  Conventionally, the toner obtained by the usual kneading and pulverization method is generally indeterminate, its particle size distribution is broad, its fluidity is low, its transferability is low, its fixing energy is high, and it is charged between toner particles. There was a problem that the amount was not uniform and the charging stability was low. Particularly in fixing, a kneading and pulverizing type toner produced by a pulverization method is effective because the pulverization breaks at the interface of the release agent (wax) and is present on the surface. Adhesion to the blade easily occurred and the performance was unsatisfactory.

  In recent years, in order to overcome these problems in the pulverization method, a toner production method by a suspension polymerization method has been proposed and implemented. A technique for producing a toner for developing an electrostatic latent image by a polymerization method is known. For example, toner particles are obtained by a suspension polymerization method. However, since the toner obtained by the suspension polymerization method encapsulates the wax, when the toner is used in an actual machine, the adhesion of the toner to the photoconductor is reduced. Compared with the pulverization method existing in the particle interface state, the amount of the wax is encapsulated, so that the wax hardly permeates the toner surface, resulting in a toner having poor fixing efficiency. Therefore, the toner is disadvantageous for power consumption. Furthermore, when the amount of wax is increased in order to improve the fixing property or when the dispersed particle size of the wax is increased, when used as a color toner, the transparency of the color image is deteriorated. Therefore, it is used as a presentation image forming toner by OHP. It is unsuitable for.

  Further, the toner particles are spherical and have a drawback of poor cleaning properties. Development and transfer with a low image area ratio results in a small amount of residual toner, and poor cleaning is not a problem. However, untransferred images were formed due to high image area ratios such as photographic images, and poor paper feed. Toner may occur on the photoreceptor as untransferred toner, and accumulation will cause image smudges. In addition, the charging roller that contacts and charges the photosensitive member is contaminated, and the original charging ability cannot be exhibited. For this reason, a method has been disclosed in which resin fine particles obtained by an emulsion polymerization method are associated to obtain amorphous toner particles (see, for example, Patent Document 3). However, in the toner particles obtained by the emulsion polymerization method, a large amount of the surfactant remains not only on the surface but also inside the particles even after the water washing step, and the environmental stability of the toner charging is impaired. The amount distribution is widened, and the background stain of the obtained image becomes poor. Further, the remaining surfactant contaminates the photoreceptor, the charging roller, the developing roller, etc., and the original charging ability cannot be exhibited.

  A solution suspension method is known as a toner production method. In this method, there is a merit that a polyester resin that can be fixed at low temperature can be used. However, in this method, since the high molecular weight component is added in the step of dissolving or dispersing the low temperature fixing resin and the colorant in the solvent, the liquid viscosity As a result, productivity problems will occur. Further, in this dissolution suspension method, toner cleaning is improved by making the surface of the toner spherical and making the surface uneven (see, for example, Patent Document 4). When a wax is added to the composition as a release agent, the uniform dispersion and dispersion state (surface presence) of the wax and the uniform dispersion of the pigment are lower than those of the kneaded and pulverized toner, and the polymer design of the bander Since the degree of freedom becomes particles in a solvent, there is a restriction on viscosity, which makes it difficult to ensure releasability.

  For the purpose of improving toner fluidity, low-temperature fixability, and hot offset property, a dry toner having a practical sphericity of 0.90 to 1.00 composed of an extension reaction product of urethane-modified polyester is proposed as a toner binder. ing. (For example, refer to Patent Document 5) In addition, a dry toner having excellent powder fluidity and transferability when it is a small particle size toner, and excellent in all of heat resistant storage stability, low temperature fixability, and hot offset resistance. It is disclosed. (For example, refer to Patent Documents 6 and 7.) The disclosed toner production methods include a high molecular weight process in which an isocyanate group-containing polyester prepolymer is polyadded with an amine in an aqueous medium.

However, the reaction is so strong that the degree of gelation in the toner is increased and the low-temperature fixability is not manifested, and the releasability from the fixing roller is poor and the effect of the offset preventing agent is not manifested. In this case, positive chargeability is likely to occur, and image fogging, smearing, insufficient resolution, etc. occurred.
JP 2002-268436 A JP 2003-167462 A Japanese Patent No. 2537503 JP 9-15903 A Japanese Patent Laid-Open No. 11-133665 JP-A-11-149180 JP 2000-292981 A

  Therefore, the present invention has been made in view of the above-mentioned problems, and the object of the present invention is to use a fixing member having excellent bending resistance and surface smoothness, and to have cleaning properties. Provided is an image forming method and an image forming apparatus using the image forming method in which a very stable and good image quality can be obtained over a long period of time by using a toner having excellent low-temperature fixability, offset resistance, and charge amount distribution. It is to be.

  As a result of investigations by the present inventors, in the fixing method using a belt-shaped heat transfer medium, the above-described toner offset to the fixing belt is prevented, the mechanical durability of the fixing belt is improved, and excellent low-temperature fixing properties and resistance are obtained. In order to obtain a stable, high-definition and good image over a long period of time by using the offset performance and the toner that becomes a good high-definition image, intensive studies were conducted. The present invention has been made based on this.

That is, the object is to make the electrostatic latent image formed on the image carrier visible as a toner image by developing means, and transfer the toner image onto a transfer material. In an image forming method for fixing,
A fixing member in which the outermost layer of the fixing member is made of fluororesins having different melt mass flow rates (according to JIS K6935-1 melt mass flow rate conditions) at 372 ° C. and 5 kgf load;
At least the compound (A) having an active hydrogen group, the compound (B) having a site capable of reacting with the compound (A), a colorant, and a release agent are dissolved or dispersed in an organic solvent, and the solution or dispersion is dissolved. It is obtained by dispersing the liquid in an aqueous medium and reacting the polymer having a site capable of reacting with the compound having an active hydrogen group, or after reacting, removing the organic solvent, washing and drying. Use toner and
The compound (A) is represented by the following general formula H2N—R—NH—R ′
R is saturated alkyl, C2 to C6
R ′ is saturated or unsaturated alkyl, C8 to C24
This is achieved by an image forming method characterized by the following.

  According to the first aspect of the present invention, by using a fixing member excellent in bending resistance and surface smoothness, and using a toner excellent in cleaning property, low temperature fixing property, offset resistance, and charge amount distribution. Therefore, it is possible to provide an image forming method in which a very stable and good image quality can be obtained over a long period of time.

  According to a second aspect of the present invention, in the first aspect of the invention, the fluororesin of the fixing member has a melt mass flow rate (based on JIS K6935-1 melt mass flow rate conditions) of 7 g / 10 min] or more and a fluororesin having a melt mass flow rate (based on JIS K6935-1 melt mass flow rate) of 3 [g / 10 min] or less at 372 ° C. and 5 kgf load. .

  According to the second aspect of the present invention, the melt mass flow rate (according to the conditions of JIS K6935-1 melt mass flow rate) is 7 [g / 10 min] or more and 3 [g under specific conditions at 372 ° C. and 5 kgf load. / 10 min] By using fluororesins having different MFR values within a specific numerical range below, it is possible to obtain a fixing belt having a balance between durability and smoothness, and further, cleaning properties and low temperature fixing properties. By using a toner excellent in offset resistance and charge amount distribution, it is possible to provide an image forming method capable of obtaining extremely stable and good image quality over a long period of time.

  A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the fluororesin of the fixing member comprises a plurality of types of fluororesins having different particle sizes.

  According to the third aspect of the present invention, the fluororesin having a small particle size among the fluororesins in the release layer smoothes the fixing belt surface, and the fluororesin having a large particle size among the fluororesins in the release layer is By making the bending resistance good, this makes it possible to obtain a fixing belt having a balance between durability and smoothness, and furthermore, a toner having excellent cleaning property, low temperature fixing property, offset resistance and charge amount distribution. By using this, it is possible to provide an image forming method in which a very stable and good image quality can be obtained over a long period of time.

  The invention according to claim 4 is the invention according to claim 3, wherein the particle size of the fluorine resin having the larger melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate) among the fluorine resins is Among the fluororesins, a fixing member having a smaller particle diameter than that of the fluororesin having a smaller melt mass flow rate (based on JIS K6935-1 melt mass flow rate conditions) is used.

  According to the invention described in claim 4, the fluorine resin particles having a small melt mass flow rate (conforming to the conditions of JIS K6935-1 melt mass flow rate) and a large particle size, and the melt mass flow rate (of JIS K6935-1 melt mass flow rate) By applying and firing a solution containing a mixture of fluororesin particles having a large particle size and a small particle size, the fluororesin particles can be dispersed in the solvent and coating unevenness can be eliminated. In this drying process, the generation of cracks can be suppressed by the fluororesin particles having a high cohesive force and a large particle diameter, and this makes it possible to provide a release layer with excellent durability in which the generation of cracks is suppressed. Furthermore, it is extremely stable by using a toner with excellent cleaning properties, low-temperature fixability, offset resistance, and charge amount distribution. Thus, it is possible to provide an image forming method capable of obtaining good image quality over a long period of time.

  The invention according to claim 5 is the invention according to any one of claims 1 to 4, wherein among the fluororesins, the fluorine having the larger melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate). A fixing member having a resin content of 35 to 60% by weight is used.

  According to the invention described in claim 5, by blending 35 to 60% by weight of the fluororesin having a larger melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate), durability and smoothness can be obtained. A well-balanced fixing belt can be obtained, and by using a toner with excellent cleaning properties, low-temperature fixing properties, offset resistance, and charge amount distribution, extremely stable and good image quality can be obtained over a long period of time. The resulting image forming method can be provided.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the fluororesin having a larger melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate) of the fluororesin A fixing member having a mixing ratio of 1: 1 with a fluororesin having a smaller melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate) among the fluororesins is used.

  According to the sixth aspect of the present invention, the fluorine resin and the melt mass flow rate (JIS K6935-1 melt) having the larger melt mass flow rate (based on JIS K6935-1 melt mass flow rate) of the fluororesin of the release layer. By making the ratio of the smaller fluororesin (based on the mass flow rate conditions) approximately the same, it is possible to obtain a fixing belt with a balance between durability and smoothness. By using a toner having excellent properties, offset resistance, and charge amount distribution, it is possible to provide an image forming method capable of obtaining extremely stable and good image quality over a long period of time.

  According to a seventh aspect of the present invention, there is provided the fixing member according to any one of the first to sixth aspects, wherein the fluororesin is a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin (PFA). It is characterized by.

  According to the seventh aspect of the present invention, a fixing member having a stable fixing performance by uniformly applying heat and pressure to the toner and the transfer material, and having elasticity and heat insulation. Furthermore, by using a toner having excellent cleaning properties, low-temperature fixability, offset resistance, and charge amount distribution, an image forming method capable of obtaining a very stable and good image quality over a long period of time can be obtained. Can be provided.

  The invention according to claim 8 is the invention according to claim 7, wherein the tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin (PFA) has a ratio of the number of oxygen atoms / number of carbon atoms in the molecular chain of 1 / A fixing member having 60 or more is used.

  According to the invention described in claim 8, by setting the ratio of the number of oxygen atoms / number of carbon atoms in the molecular chain to 1/60 or more, crystallization is suppressed and bending resistance (bending life) is improved. In addition, it is possible to obtain a fixing belt having excellent durability, and furthermore, by using a toner having excellent cleaning properties, low-temperature fixing properties, offset resistance, and charge amount distribution, an extremely stable and good image quality can be obtained for a long time. An image forming method obtained over a wide range can be provided.

  According to a ninth aspect of the present invention, in the invention according to any one of the first to eighth aspects, a fixing member having a thickness of the outermost layer of 20 μm or more is used.

  According to the invention described in claim 9, by making the layer thickness 20 μm or more, the layer of the fluororesin particles applied and adhered to the elastic layer is in accordance with the conditions of melt mass flow rate (JIS K6935-1 melt mass flow rate). ) With large fluororesin particles and small fluororesin particles with a melt mass flow rate (based on the conditions of JIS K6935-1 melt mass flow rate) are dispersed to form a fixing belt having excellent bending resistance and surface smoothness. Furthermore, by using a toner having excellent cleaning properties, low-temperature fixability, offset resistance, and charge amount distribution, it is possible to provide an image forming method capable of obtaining a very stable and good image quality over a long period of time. .

  The invention according to claim 10 is the toner according to any one of claims 1 to 9, wherein the site capable of reacting with the compound (A) having an active hydrogen group of the compound (B) is an isocyanate group. It is characterized by using.

  According to the tenth aspect of the present invention, the compound constituting the toner has a three-dimensional cross-linking structure to become a polymer binder component, thereby improving the low-temperature fixability and high-temperature offset resistance of the toner, and further fixing. A toner for developing an electrostatic image with improved releasability from a roller can be obtained.Furthermore, by using a fixing member having excellent bending resistance and surface smoothness, extremely stable and good image quality can be obtained over a long period of time. An image forming method obtained in this way can be provided.

  According to an eleventh aspect of the present invention, there is provided the toner according to any one of the first to ninth aspects, wherein the site capable of reacting with the compound (A) having an active hydrogen group of the compound (B) is an epoxy group. It is characterized by using.

  According to the eleventh aspect of the present invention, the compound constituting the toner has a three-dimensional cross-linking structure to become a polymer binder component, thereby improving the low-temperature fixability and high-temperature offset resistance of the toner, and further fixing. A toner for developing an electrostatic image with improved releasability from a roller can be obtained.Furthermore, by using a fixing member having excellent bending resistance and surface smoothness, extremely stable and good image quality can be obtained over a long period of time. An image forming method obtained in this way can be provided.

  According to a twelfth aspect of the invention, in the invention according to any one of the first to ninth, tenth, and / or eleventh aspects, the toner has a weight average particle diameter of 3 to 8 μm.

  According to the invention of claim 12, by using a toner having a weight average particle diameter of 3 to 8 μm and further using a fixing member having excellent bending resistance and surface smoothness, high resolution and extremely stable Thus, it is possible to provide an image forming method capable of obtaining good image quality over a long period of time.

  According to a thirteenth aspect of the present invention, in the invention according to any one of the first to ninth, tenth and tenth and / or eleventh and twelfth aspects, the toner has a weight average particle diameter / number average particle diameter of 1.25 or less. It is characterized by that.

  According to the invention of claim 13, by using a toner having a weight average particle diameter / number average particle diameter of 1.25 or less, and further using a fixing member having excellent bending resistance and surface smoothness, It is possible to provide an image forming method capable of obtaining excellent image quality with high resolution and extremely stable over a long period of time.

  The invention according to claim 14 is the invention according to any one of claims 1 to 9, 10 and / or 11, 12 to 13, wherein the glass transition point of the toner is 40 ° C to 70 ° C. And

  According to the fourteenth aspect of the present invention, the toner having a glass transition point of 40 ° C. to 70 ° C. is excellent in heat-resistant storage stability even when the glass transition point is low, and further has flexibility and surface smoothness. By using an excellent fixing member, it is possible to provide an image forming method in which a very stable and good image quality can be obtained over a long period of time.

According to a fifteenth aspect of the invention, in the invention according to any one of the first to ninth, ten and ten and / or 11, 12 to 14, the BET specific surface area of the toner is 1.0 to 6.0 m ² / g. It is characterized by being.

According to the invention of claim 15, by using a toner having a BET specific surface area of 1.0 to 6.0 m ² / g, and further using a fixing member having excellent bending resistance and surface smoothness, It is possible to provide an image forming method in which excellent image quality with excellent resolution and extremely stable can be obtained over a long period of time.

  The invention according to claim 16 includes at least an image carrier, a toner image forming unit that forms a toner image on the image carrier, a transfer unit that transfers the toner image on the image carrier to a transfer material, An image forming apparatus comprising a fixing unit that fixes a toner image on the transfer material, wherein the image forming method according to any one of claims 1 to 9, 10 and / or 11, 12 to 15 is used. Achieved by the image forming apparatus.

  According to the invention described in claim 16, by using a fixing member excellent in bending resistance and surface smoothness, and using a toner excellent in cleaning property, low temperature fixing property, offset resistance and charge amount distribution. Thus, it is possible to provide an image forming apparatus using an image forming method that can obtain a very stable and good image quality over a long period of time.

  According to the present invention, the fluororesin in the outermost layer of the fixing member is made of a plurality of types of fluororesins having different MFRs, and a mixture of fluororesins having a large MFR and fluororesins having a low MFR. Of the outermost fluororesins, the fluororesin having a larger MFR flows during firing and improves the smoothness of the surface of the fixing member. Of the outermost fluororesins, the fluororesin having the smaller MFR improves the bending resistance of the fixing member. As described above, since the outermost fluororesin of the fixing member is made of a plurality of types of fluororesins having different MFRs, a fixing member having excellent bending resistance and surface smoothness can be used. In particular, the fluororesin of the fixing member is composed of a fluororesin having an MFR of 7 [g / 10 min] or more at 372 ° C. and 5 kgf load, and a fluororesin having an MFR of 3 [g / 10 min] or less at 372 ° C. and 5 kgf load. Thus, it is possible to effectively use a fixing member having excellent bending resistance and surface smoothness.

  Further, at least the compound (A) having an active hydrogen group, the compound (B) having a site capable of reacting with the compound (A), a colorant, and a release agent are dissolved or dispersed in an organic solvent, and the solution is obtained. Or after dispersing the dispersion in an aqueous medium and reacting the polymer having a site capable of reacting with the compound having an active hydrogen group, or while reacting, the organic solvent is removed, washed and dried. In the obtained toner, the compound (A) is H2N—R—NH—R ′, R is saturated alkyl and C2 to C6, and R ′ is saturated or unsaturated alkyl and C8 to C24. Therefore, it is possible to use a toner for developing an electrostatic charge image that has improved properties, improved high-temperature offset resistance, and improved releasability from the fixing roller.

  Therefore, by using a fixing member with excellent bending resistance and surface smoothness and a toner with excellent cleaning properties, low-temperature fixing properties, offset resistance, and charge amount distribution, extremely stable, high-definition and good image quality However, it is possible to provide an image forming method that can be obtained over a long period of time, and to provide an image forming apparatus that employs the image forming method.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Note that it is easy for a person skilled in the art to make other embodiments by changing or correcting the present invention within the scope of the claims, and these changes and modifications are included in the scope of the claims. The following description is an example of the best mode of the present invention, and does not limit the scope of the claims.

  FIG. 1 shows an example of an image forming apparatus according to the present invention. In this image forming apparatus, a plurality of image forming units 10Y, 10M, 10C, and 10Bk are arranged in order from the upstream side in the moving direction along a conveying belt 20 that conveys a transfer sheet P as a recording medium. This is a tandem type image forming apparatus. The moving body driving device according to the present invention can be used as a driving device for the conveyance belt 20 which is a moving body of the tandem type image forming apparatus.

  Each image forming unit in this image forming apparatus is configured to sequentially form images of 10Y in yellow, 10M in magenta, 10C in cyan, and 10Bk in black by a known electrophotographic process. Each of these image forming units has a common internal configuration except that the color of the image to be formed is different. Therefore, as shown in FIG. 1, the image forming units are distinguished from each other by adding the letters Y, M, C, and Bk to the end of the reference numerals indicating the common components. I will do it. In the following description, the configuration of the image forming unit 10Y is mainly shown, and the configuration of the image forming unit 10Y is shown to show the configuration of other image forming units.

  In FIG. 1, the conveyance belt 20 is configured by an endless endless belt. The conveyor belt 20 is rotatably stretched by a driving roller 7 that is driven and rotated and a driven roller 8 that is driven and rotated, and rotates in the direction of the arrow as the driving roller 7 rotates. A paper feed tray 50 that stores a bundle of transfer paper is disposed below the transport belt 20. Among the transfer paper bundles stored in the paper feed tray 50, the uppermost transfer paper P is sent out at the time of image formation and is attracted to the outer peripheral surface of the transport belt 20 by electrostatic attraction. The transfer paper P adsorbed on the outer peripheral surface of the transport belt 20 is first transported to the image forming unit 10Y arranged on the most upstream side in the rotation direction of the transport belt 20.

  The image forming unit 10Y includes a photosensitive drum 1Y as an image carrier, a charger 2Y disposed around the photosensitive drum 1Y, an exposure device 3Y, a developing device 4Y, a photosensitive cleaner 6Y, and the like. The exposure device 3Y is composed of a laser scanner, and is configured to reflect the laser light from the laser light source with a polygon mirror and to emit the laser light through an optical system using an fθ lens, a deflection mirror, and the like. The peripheral surface of the photosensitive drum 1Y is uniformly charged by the charger 2Y in the dark during image formation. Thereafter, a laser beam composed of image light corresponding to the yellow image from the exposure device 3Y is exposed on the peripheral surface of the charged photosensitive drum 1Y. By this exposure, an electrostatic latent image corresponding to the yellow image is formed on the peripheral surface of the photosensitive drum 1Y. The electrostatic latent image is visualized with yellow toner supplied from the developing device 4Y. Thereby, a yellow toner image is formed on the photoreceptor drum 1Y. This yellow toner image is transferred onto the transfer paper P by a transfer device 5Y disposed opposite the photoconductor drum 1Y with the transport belt 20 in between at a transfer position where the photoconductor drum 1Y and the transfer paper P on the transport belt 20 are in contact with each other. Transcribed. By this transfer, a yellow toner image is formed on the transfer paper P. After the transfer, the photoreceptor drum 1Y is prepared for the next image formation by removing unnecessary toner remaining on the peripheral surface thereof by the photoreceptor cleaner 6Y.

  In this way, the transfer paper P on which the yellow toner image is transferred by the image forming unit 1Y is transported to the next image forming unit 10M by the transport belt 20. In the image forming unit 10M, a magenta toner image is formed on the photosensitive drum 1M by the same process as that in the image forming unit 10Y. The magenta toner image is transferred to the yellow toner image on the transfer paper P by the transfer device 5M at the transfer position where the photosensitive drum 1M and the transfer paper P on the transport belt 20 are in contact with each other.

  The transfer paper P onto which the yellow toner image and the magenta toner image have been transferred is transported to the next image forming unit 10C by the transport belt 20. In this image forming unit 10C, a cyan toner image is formed on the photosensitive drum 1C by the same process as in the case of the image forming units 10Y and 10M. This cyan toner image is transferred onto the yellow toner image and the magenta toner image on the transfer paper P by the transfer device 5C at the transfer position where the photosensitive drum 1C and the transfer paper P on the transport belt 20 are in contact with each other.

  The transfer paper P on which the toner images of each color of yellow, magenta, and cyan are transferred is transported to the next image forming unit 10Bk by the transport belt 20. In this image forming unit 10Bk, a black toner image is formed on the photosensitive drum 1Bk in the same manner as in the image forming units 10Y, 10M, and 10C. This black toner image is transferred onto the toner images of the respective colors on the transfer paper P by the transfer device 5Bk at the transfer position where the photosensitive drum 1Bk and the transfer paper P on the transport belt 20 are in contact with each other.

  As a result, a full-color color image is formed on the transfer paper P by combining toner images of yellow, magenta, cyan, and black. Then, the transfer paper P on which the full-color composite image is formed passes through the image forming unit 10Bk, is peeled off from the conveying belt 20 and fixed by the fixing device 40, and then discharged.

  FIG. 2 is an explanatory diagram of the belt-type fixing device 40. As shown in FIG. 2, the fixing device 40 includes a fixing belt 45 that is rotatably provided by a heating roller 44 and a fixing roller 41. The fixing roller 41 has a heat-resistant sponge rubber layer on the outer periphery of a metal core. The heating roller 44 incorporates heating means such as a halogen lamp 46 in a metal core, and the fixing belt 45 is heated from the inside by this radiant heat. Further, a thermistor 49 that is a temperature sensor element is disposed at a position facing the heating roller 44, and the surface temperature of the fixing belt 45 is detected by contacting the center portion of the fixing belt 45. The heating roller 44 is set at a control set temperature, and based on the temperature detection of the thermistor 49, the lighting of the halogen lamp 46 is controlled by a temperature control device (not shown) so as to reach the set temperature. Further, a pressure roller 42 is provided so as to be in contact with the fixing roller 41 via the fixing belt 45. The pressure roller 42 presses the fixing roller 45 with a spring 43. Further, the pressure roller 42 is rotated by a driving means (not shown), whereby the fixing roller 41 is driven to rotate. A tension roller 47 that is in contact with the vicinity of the central portion of the fixing belt 45 is provided upstream of the fixing nip where the pressure roller 42 is in contact with the moving direction of the fixing belt. The tension roller 47 is pressed to the left side in the drawing by a spring 48, whereby a tension is applied to the fixing belt 45. In this embodiment, the driving means is provided on the pressure roller 42. However, the driving means may be provided on the fixing roller 41 and the pressure roller 42 may be driven to rotate. Further, the pressure roller 42 and the fixing roller 41 are engaged with each other by a gear so that the driving force of the driving means is transmitted to both the pressure roller 42 and the fixing roller 41 via the gear. May be driven to rotate.

  Such a belt type fixing device 40 fixes the toner adhering to the transfer paper P by passing the transfer paper between the fixing belt 45 heated by the heating roller 44 and the pressure roller 42. The belt 45 is pressed by the pressure roller 42 while being softened by the heat of the belt 45 and fixed on the transfer paper.

  FIG. 3 is a cross-sectional view of the fixing belt 45. As shown in FIG. 3, an elastic layer 452 made of silicone rubber is provided on the outer periphery of a cylindrical film base 451 made of a heat resistant resin such as polyimide via a primer. Furthermore, a release layer 453 made of a fluororesin and having a layer thickness of 20 μm or more is provided on the outer periphery of the elastic layer 452 through a primer. The base 451 may be a material having heat resistance and mechanical strength, and may be, for example, a metal such as Ni or SUS in addition to a heat resistant resin such as polyimide. The elastic layer 452 may be a material that uniformly applies heat and pressure to the toner and the transfer paper in order to obtain stable fixing performance, and may be a material that has elasticity and heat insulation properties. The release layer 453 may be a known fluororesin such as polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), or the like. A blended material can be used. The release layer made of the material as described above can be obtained by applying and baking the elastic layer 452 via a primer.

  The fluororesin of the release layer is made of a fluororesin having a different MFR. In addition, MFR described here is based on the conditions of JISK6935-1 melt mass flow rate. A fluororesin having a large MFR is excellent in fluidity when melted. For this reason, the fluororesin having a large MFR attached to the elastic layer can form a uniform film on the surface of the fixing belt by baking, and can be a fixing belt having high surface smoothness. However, since a fluororesin having a large MFR has poor bending resistance, cracks are likely to occur during use due to stretching of the fixing roller 41 and the heating roller 44, pressurization of the tension roller 47, and the like. On the other hand, since a fluororesin having a small MFR is excellent in bending resistance, cracks hardly occur even when used for a long time. However, since the fluororesin having a low MFR has poor fluidity when melted, the fluororesin that has been applied and adhered to the elastic layer does not flow during firing, and thus cannot form a uniform film on the surface of the fixing belt. . For this reason, the fixing belt has unevenness on the surface and poor smoothness. As described above, the fluororesin of the release layer is made of a fluororesin having a different MFR, so that the fluororesin having the larger MFR among the fluororesins of the release layer smoothes the surface of the fixing belt and releases the release layer. Of these fluororesins, a fluororesin having a smaller MFR has good bending resistance. Thereby, it is possible to obtain a fixing belt in which durability and smoothness are balanced. In particular, the fluororesin of the fixing member is composed of a fluororesin having an MFR of 7 [g / 10 min] or more at 372 ° C. and 5 kgf load, and a fluororesin having an MFR of 3 [g / 10 min] or less at 372 ° C. and 5 kgf load. Thus, a fixing member having excellent bending resistance and surface smoothness can be obtained.

  Of the above fluororesins, it is preferable to blend 35 to 60% by weight of the fluororesin having the larger MFR, and the mixing ratio of the fluororesin having the larger MFR and the fluororesin having the smaller MFR is selected. It is more preferable to use 1: 1. As described above, the ratio of the fluororesin having a larger MFR and the fluororesin having a smaller MFR in the release layer is substantially the same, so that the fixing belt has a balance between durability and smoothness. It can be. Moreover, it is preferable that the thickness of a mold release layer shall be 20 micrometers or more. When the thickness of the release layer is 20 μm or less, it is difficult to form a layer in which fluororesin particles having a small MFR and fluororesin particles having a large MFR are dispersed in the fluororesin particles applied and adhered to the elastic layer. Therefore, as shown in FIG. 4A, there are a layer formed only with fluororesin particles having a large MFR and a layer formed only with fluororesin particles having a small MFR. The fixing belt made by firing the fluororesin particles formed with such a layer has poor bending resistance at the portion of the layer formed only with a fluororesin having a large MFR, and cracks easily occur. The portion of the layer formed of only a small fluororesin protrudes and the surface smoothness is impaired. However, by setting the layer thickness to 20 μm or more as described above, the layer of the fluororesin particles applied and adhered to the elastic layer as shown in FIG. 4B is composed of fluororesin particles having a large MFR and a small MFR. It becomes a layer in which the fluororesin particles are dispersed. Thereby, it is possible to obtain a fixing belt having good bending resistance and surface smoothness.

  Further, when the release layer is formed by applying and baking the fluororesin particles, it is preferable to use at least two types of fluororesins in which a fluororesin having a large particle size and a fluororesin having a small particle size are mixed. Since the fluororesin particles having a small particle size have low cohesiveness, they can be uniformly dispersed in a solvent such as water. However, when a solution consisting only of a solvent and a fluororesin particle having a small particle size is applied to the elastic layer, cracks are likely to occur in the drying process for removing the solvent. On the other hand, since the fluororesin particles having a large particle size have a strong cohesive force, cracks are unlikely to occur in the drying step after coating. However, since fluororesin particles having a large particle size cannot be sufficiently dispersed in a solvent such as water, when a solution of only a solvent such as water and a fluororesin particle having a large particle size is applied, the fluororesin particles are elastic. It may not adhere uniformly to the layer and may cause so-called coating unevenness. For this reason, as described above, by applying and baking a solution in which fluororesin particles having a large particle diameter and small fluororesin particles are mixed, the fluororesin particles can be dispersed in the solvent, and coating unevenness can be eliminated. Can do. Furthermore, in the drying process after coating, the generation of cracks can be suppressed by the fluororesin particles having a large particle size and high cohesive force. Thereby, it can be set as the release layer excellent in durability in which generation | occurrence | production of the crack was suppressed.

  For the release layer 453, a PFA that is a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether having excellent bending resistance, non-adhesiveness, and abrasion resistance is used, so that a fixing belt having high durability can be obtained. be able to. Furthermore, it is preferable to increase the number of perfluoroalkyl vinyl ether components and use PFA having a ratio of the number of oxygen atoms / number of carbon atoms in the molecular chain of 1/60 or more. FIG. 5 shows the bending resistance of PFA having a ratio of oxygen atoms / carbon atoms in the molecular chain of 1/60 or more and PFA having a ratio of oxygen atoms / carbon atoms in the molecular chain of 1/100 or less. It is the graph which investigated about. The solid line in the figure is a PFA having a ratio of the number of oxygen atoms / carbon atoms in the molecular chain of 1/60 or more, and the dotted line in the figure has a ratio of oxygen atoms / carbon atoms in the molecular chain of 1 / 100 or less PFA. As can be seen from FIG. 5, regardless of the MFR value, PFA having a ratio of the number of oxygen atoms / carbon atoms in the molecular chain of 1/60 or more has a ratio of the number of oxygen atoms / carbon atoms in the molecular chain. It can be seen that the bending resistance is improved as compared with PFA of 1/100 or less. This is probably because PFA having a ratio of the number of oxygen atoms / number of carbon atoms in the molecular chain of 1/60 or more is suppressed from crystallization and has improved bending resistance (bending life).

  In the above description, the release layer is obtained by applying and baking the elastic layer 452 via a primer. However, the present invention is not limited to this. For example, a fluororesin tube is formed by extruding a fluororesin. A release layer can also be prepared by coating an elastic layer with a primer and baking. However, when the durability and smoothness of the fixing belt 45 are taken into consideration, the thickness of the release layer is preferably 20 μm or more. When a release layer having a thickness of 20 μm or more is created, the release layer is applied via the above-described primer. -The method of firing is most suitable. The fixing belt 45 described above has a three-layer structure including a film base 451, an elastic layer 452, and a release layer 453, but may have a two-layer structure including a film base 451 and a release layer 453.

  Hereinafter, the toner according to the present invention will be described in detail.

  In the method of obtaining the toner in the aqueous medium, the compound constituting the toner has a three-dimensional cross-linked structure to become a polymer binder component, which improves the low-temperature fixability of the toner, improves the high-temperature offset resistance, An electrostatic image developing toner having improved releasability from the fixing roller can be obtained.

  That is, generally in the reaction of a compound having a site capable of reacting with a compound having an active hydrogen group, when the site capable of reacting is an isocyanate group and / or an epoxy group, the compound having an active hydrogen group is low alkyl. Grade diamines are often used. In such a case, the toner reacts rapidly during the production of the toner used in the present invention, takes a strong cross-linked structure, and cannot obtain a predetermined fixing property. For example, when a negatively charged toner is produced. Exhibited a positive chargeability due to the urea bond or residual amine group, which was an adverse effect on good image formation. In addition, ketimine compounds and the like have been proposed to mitigate rapid reaction, but the reaction rate can be mitigated, but the effect of improving the fixing property is not seen. The toner of the present invention relaxes the reaction rate and realizes low-temperature fixability, and also improves the releasability of the toner due to the presence of a higher alkyl group.

  In the organic solvent and / or during its removal, the primary amine moiety in the diamine of the present invention immediately reacts to form a part of the crosslinked structure, but it is not strong and has a high degree of freedom. Furthermore, a secondary amine moiety reacts with time, and finally a toner having a cross-linked structure and satisfying high temperature offset and low temperature fixability is developed. It is thought that a typical three-dimensional structure is formed. In addition, the reactive bond usually has a relatively positive charging property and improves the adhesion to the fixing roller, but its effect is suppressed by the presence of a higher alkyl group, and proper charging characteristics and separation are achieved. Type characteristics develop.

The compound (A) having an active hydrogen group used in the present invention has the general formula H2N—R—NH—R ′.
R = C2 to C6
R ′ = C8 to C24
Wherein R represents a short-chain saturated alkyl having 2 to 6 carbon atoms, R ′ represents a long-chain saturated or unsaturated alkyl having 8 to 24 carbon atoms, for example, It is obtained as a derivative such as 1,3-propyldiamine, 1,6-hexyldiamine. These compounds may be used alone or in combination of two or more as the compound (A). Examples include N-octyl-1,3 propyl diamine, N-lauryl-1,3 propyl diamine, N-palmityl-1,3 propyl diamine, N-stearyl-1,3 propyl diamine, N-behenyl-1 , 3propyldiamine, N-oleyl-1,3propyldiamine, N-linolenyl-1,3propyldiamine, N-octyl-1,6hexyldiamine, N-lauryl-1,6hexyldiamine, N-palmityl-1 , 6 hexyl diamine, N-stearyl-1,6 hexyl diamine, N-behenyl-1,6 hexyl diamine, N-oleyl-1,6 hexyl diamine, N-linolenyl-1,6 hexyl diamine, etc., and mixtures As such, palm oil-modified alkyl diamine, beef tallow-modified alkyl diamine and the like are also used in the present invention. Here, when the compound (A) is a primary diamine or a ketimine compound that is a derivative thereof, the organic solvent solution or dispersion is dissolved in the aqueous medium and dissolved in the aqueous medium to form the compound (B). The reaction cannot be performed, and even if it reacts to some extent, the crosslinked structure is very strong and the low-temperature fixability of the toner is not exhibited. The same applies to the case where R ′ has 8 or more carbon atoms, and even if it reacts with the compound (B), the releasability from the fixing roller is poor and an appropriate low-temperature fixing width cannot be obtained. . When R ′ has 25 or more carbon atoms, the reaction with the compound (B) does not proceed rapidly due to the steric hindrance of the molecule, and a high temperature offset phenomenon occurs in which toner is taken on the roller during fixing. Similarly, the fixing width cannot be obtained.

  The compound (B) used in the present invention is not particularly limited as long as it reacts with the active hydrogen group of the compound (A), but is preferably selected from the group of compounds having an isocyanate group or an epoxy group. It is. Preferably, the compound (B) is selected from polyisocyanates or polyepoxy compounds having one or more of these isocyanate groups or epoxy groups per molecule, and the skeleton is not limited but is preferably polyester, Examples include polyether and polystyrene acrylic oligomer.

  Examples of the polyester compound (B1) having an isocyanate group include a polycondensate of a polyol (1) and a polycarboxylic acid (2) and a polyester having an active hydrogen group, which is further reacted with a polyisocyanate compound (3). Can be mentioned. Examples of the active hydrogen group possessed by the polyester include hydroxyl groups (alcoholic hydroxyl groups and phenolic hydroxyl groups), amino groups, carboxyl groups, mercapto groups, and the like. Among these, alcoholic hydroxyl groups are preferred.

  The polyester compound (B1) is not particularly limited, and a known polyester resin is used as long as it is soluble in an organic solvent. Examples thereof include a polycondensate of polyol (1) and polycarboxylic acid (2).

  Examples of the polyol (1) include a diol and a trivalent or higher polyol, and the diol alone or a mixture of a diol and a small amount of a trivalent or higher polycarboxylic acid is preferable. Examples of the diol include alkylene glycols having 2 to 18 carbon atoms (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, dodecanediol. An alkylene ether glycol having 4 to 1000 carbon atoms (diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc.); an alicyclic diol having 1 to 5 carbon atoms (1, 4-cyclohexanedimethanol, hydrogenated bisphenol A, etc.); bisphenols having 12 to 23 carbon atoms (bisphenol A, bisphenol F, bisphenol S, etc.); Or alkylene oxides having 2 to 18 carbon atoms (ethylene oxide, propylene oxide, butylene oxide, α-olefin oxide, etc.) adducts (addition mole number is 2 to 20) of bisphenols. Among these, preferred are alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts having 2 to 18 carbon atoms of bisphenols, and particularly preferred are alkylene oxide adducts (particularly bisphenol A) of bisphenols (especially bisphenol A). 2 to 3 mol adduct of ethylene oxide or propylene oxide) and an alkylene glycol having 2 to 12 carbon atoms (especially ethylene glycol, 1,2-propylene glycol, 1,4-butanediol, neopentyl glycol) It is a combination. In the case of the combined use, the alkylene oxide adduct of bisphenols is usually at least 30 mol%, preferably at least 50 mol%, particularly preferably at least 70 mol%. Examples of the trihydric or higher polyol include trihydric to octahydric or higher polyhydric aliphatic alcohols (glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, etc.); trihydric to octahydric or higher phenols (Trisphenol PA, phenol 3m borak, cresol novolak, etc.); C2-C18 alkylene oxide adducts (added mole number: 2 to 20) of the above trivalent or more polyphenols.

  Examples of the polycarboxylic acid (2) include a dicarboxylic acid and a tricarboxylic or higher polycarboxylic acid, and a dicarboxylic acid alone or a mixture of a dicarboxylic acid and a small amount of a trivalent or higher polycarboxylic acid is preferable. Examples of the dicarboxylic acid include alkylene dicarboxylic acids having 2 to 20 carbon atoms (succinic acid, adipic acid, sebacic acid, dodecane dicarboxylic acid, dodecenyl succinic acid, dodecyl succinic acid, etc.); alkenylene dicarboxylic acids (maleic acid, fumaric acid, etc.); Group dicarboxylic acids (phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, etc.). Of these, preferred are alkenylene dicarboxylic acids having 4 to 20 carbon atoms (particularly adipic acid and dodecenyl succinic acid) and aromatic dicarboxylic acids having 8 to 20 carbon atoms (particularly isophthalic acid and terephthalic acid). Examples of the trivalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms (such as trimellitic acid and pyromellitic acid). In addition, as polycarboxylic acid (2), you may make it react with polyol (1) using the acid anhydride or lower alkyl ester (methyl ester, ethyl ester, isopropyl ester, etc.) of the above-mentioned thing.

  The ratio of the polyol (1) to the polycarboxylic acid (2) is usually 2/1 to 1/2, preferably 1., as the molar ratio [OH] / [COOH] of the hydroxyl group [OH] to the carboxyl group [COOH]. 5/1 to 1 / 1.5, more preferably 1.3 / 1 to 1 / 1.3.

  Examples of the polyisocyanate compound (3) include aliphatic polyisocyanates (tetramethylene diisocyanate, hexamethylene diisocyanate, 2,6-diisocyanatomethylcaproate, etc.); alicyclic polyisocyanates (isophorone diisocyanate, cyclohexylmethane diisocyanate, etc.); Aromatic diisocyanates (tolylene diisocyanate, diphenylmethane diisocyanate, etc.); araliphatic diisocyanates (α, α, α ′, α′-tetramethylxylylene diisocyanate, etc.); isocyanurates; the polyisocyanates are phenol derivatives, oximes, caprolactams And a combination of two or more of these. The ratio of the polyisocyanate compound (3) is usually 5/1 to 1/1, preferably 4 as the equivalent ratio [NCO] / [OH] of the isocyanate group [NCO] and the hydroxyl group [OH] of the polyester having a hydroxyl group. / 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. When [NCO] / [OH] exceeds 5, low-temperature fixability deteriorates. If the molar ratio of [NCO] is less than 1, the urea content in the modified polyester will be low, and the hot offset resistance will deteriorate. The content of the polyisocyanate (3) component in the compound (B) having an isocyanate group is usually 0.5 to 40% by weight, preferably 1 to 30% by weight, and more preferably 2 to 20% by weight. If it is less than 0.5% by weight, the hot offset resistance deteriorates, and it is disadvantageous in terms of both heat-resistant storage stability and low-temperature fixability. On the other hand, if it exceeds 40% by weight, the low-temperature fixability deteriorates. The number of isocyanate groups contained per molecule in the compound (B) having an isocyanate group is usually 1 or more, preferably 1.5 to 3 on average, more preferably 1.8 to 2.5 on average. is there. When the number is less than 1 per molecule, the molecular weight of the polymer component due to the reaction with the compound (A) becomes low, and the hot offset resistance and the like deteriorate.

  Examples of the polyester compound (B2) having an epoxy group include those obtained by reacting a polyester having an active hydrogen group with a polyepoxide, which is a polycondensate of a polyol and a polycarboxylic acid. The polyester of polyol and polycarboxylic acid is not limited at all, but is preferably selected from the above polyols and polycarboxylic acids. Polyepoxides include polyglycidyl ethers (ethylene glycol diglycidyl ether, tetramethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, glycerin triglycidyl ether, pentaerythritol tetraglycidyl ether, phenol novolac glycidyl ether compounds, etc. ); Diene oxide (pentadiene dioxide, hexadiene dioxide, etc.) and the like. Of these, polyglycidyl ether is preferred. The ratio of the polyepoxide is usually 5/1 to 1/1, preferably 4 as the equivalent ratio [BY] / [OH] of the total hydroxyl group [OH] of the epoxy group [BY] and the hydroxyl group polyester and polyol. / 1 to 1.2 / 1, more preferably 2.5 / 1 to 1.5 / 1. The content of the polyepoxide component in the polyester compound (B2) having an epoxy group is usually 0.5 to 40% by weight, preferably 1 to 30% by weight from the viewpoint of hot offset resistance, heat resistant storage stability and low temperature fixability. %, More preferably 2 to 20% by weight.

  The colorant used in the present invention may be an inorganic pigment, an organic pigment or an organic dye, or a combination thereof. Specific examples of these include carbon black, aniline blue, phthalocyanine blue, phthalocyanine green, hansa yellow, rhodamine dyes, chrome yellow, quinacridone, benzidine yellow, rose bengal, triallylmethane dye, monoazo, disazo. Any known dye / pigment such as a dye or a condensed azo dye / pigment can be used alone or in combination. In the case of a full color toner, it is preferable to use benzidine yellow as a yellow, monoazo type or condensed azo dye / pigment, quinacridone as a magenta, monoazo dye / pigment, and phthalocyanine blue as cyan. Of these, as the cyan colorant, Pigment Blue 15: 3, as the yellow colorant, Pigment Yellow 74 and Pigment Yellow 93, and as the magenta colorant, quinacridone compounds are preferably used. The addition amount of the colorant is preferably in the range of 2 to 25 parts by weight with respect to 100 parts by weight of the total toner components. The colorant used in the present invention can also be used as a master batch combined with a resin. As the binder resin to be kneaded with the production of the masterbatch or the masterbatch, styrene and substituted polymers thereof such as polyester resins, polystyrene, poly p-chlorostyrene, and polyvinyltoluene; styrene-p-chlorostyrene copolymer Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer , Styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene -Acrylonitrile copolymer Styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Styrene copolymers such as: polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin , Modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like, which can be used alone or in combination. This master batch can be obtained by mixing and kneading a resin for a master batch and a colorant under a high shear force to obtain a master batch. In this case, water or an organic solvent can be used in order to enhance the interaction between the colorant and the resin. In addition, a so-called flushing method, which is a wet cake of a colorant, is a method of mixing and kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, transferring the colorant to the resin side, and removing moisture and organic solvent components. Since it can be used as it is, it does not need to be dried and is preferably used. For mixing and kneading, a high shear dispersion device such as a three-roll mill is preferably used.

  As the release agent used in the present invention, known ones can be used, and the method of introduction into the toner may be a known method such as dissolution / dispersion in an organic solvent within the scope of the present invention. Used. The types include polyolefin wax (polyethylene wax, polypropylene wax, etc.); long chain hydrocarbon (paraffin wax, sazol wax, etc.); carbonyl group-containing wax. Of these, carbonyl group-containing waxes are preferred. Carbonyl group-containing waxes include polyalkanoic acid esters (carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, 1,18. -Octadecandiol-bis-stearate, etc.); polyalkanol esters (tristearyl trimellitic acid, distearyl maleate, etc.); polyalkanoic acid amides (ethylenediamine dibehenylamide, etc.); polyalkylamides (trimellitic acid tristearylamide) And dialkyl ketone (such as distearyl ketone). Other examples include crystalline polyester resins that exhibit melting point behavior. Among these carbonyl group-containing waxes, preferred are polyalkanoic acid esters and crystalline polyester resins, and it is more effective to use two or more types having different melting behaviors. The content of the release agent in the toner is usually 0.5 to 40 parts by weight, preferably 2 to 30% by weight, particularly preferably 3 to 25% by weight.

  As the charge control agent used as necessary in the toner of the present invention, any known one can be used alone or in combination, metal chelates, metal salts of organic acids, metal-containing dyes, nigrosine dyes, Examples include amide group-containing compounds, phenol compounds, naphthol compounds and their metal salts, urethane bond-containing compounds, and acidic or electron-withdrawing organic substances. In consideration of color toner adaptability (the charge control agent itself is colorless or light in color and does not impair the color tone of the toner), as the negative chargeability, metal salts of salicylic acid or alkylsalicylic acid with chromium, zinc, aluminum, etc., Metal complexes, metal salts of benzylic acid, metal complexes, amide compounds, phenol compounds, naphthol compounds, phenolamide compounds, 4,4′-methylenebis [2- [N- (4-chlorophenyl) amide] -3-hydroxynaphthalene ] And the like are preferable. The amount used may be determined according to the desired charge amount for the toner, but is usually 0.01 to 10 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the toner.

  In the present invention, other binder resins can be used as necessary. The binder resin is not particularly limited, and known ones are used. For example, polyester resins, polystyrene, poly-p-chlorostyrene, polyvinyltoluene and other styrene and substituted polymers thereof; styrene-p -Chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene- Butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethacrylic acid Methyl copolymer, styrene-acrylonitrile copolymer , Styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer, etc. Styrene copolymer of polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, Modified rosin, terpene resin, aliphatic or alicyclic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax and the like can be mentioned, and these can be used alone or in combination. Among these, the polyester resin which consists of the above-mentioned polyalcohol and polycarboxylic acid is preferable. The amount used is not particularly limited, but is usually 20 to 95 parts by weight, preferably 30 to 90 parts by weight per 100 parts by weight of the toner.

  A method for producing the toner used in the present invention will be described.

  The toner production method used in the present invention includes at least a compound (A) having an active hydrogen group, a compound (B) having a site capable of reacting with the compound (A), a colorant, and a release agent in an organic solvent. Dissolve or disperse, disperse the solution or dispersion in an aqueous medium, and remove the organic solvent after reacting or reacting the polymer having a site capable of reacting with the compound having an active hydrogen group. As long as the toner is washed and dried, the production method is not limited. For example, a compound (A) having an active hydrogen group in an organic solvent, a compound (B) having a site capable of reacting with the compound (A), a colorant, a release agent, and a binder resin are dissolved. Then, it is dispersed and / or dissolved to a predetermined particle size with a low-speed shearing method and / or a high-speed shearing type disperser, and then dispersed in a predetermined aqueous medium with a predetermined particle size. The dispersion method is not particularly limited, and known equipment such as a low-speed shear method, a high-speed shear method, a friction method, a high-pressure jet method, and an ultrasonic wave can be applied. A high-speed shearing method is preferable in order to make the particle size of the dispersion 2 to 20 μm. When a high-speed shearing disperser is used, the number of rotations is not particularly limited, but is usually 1000 to 3000 rpm, preferably 5000 to 20000 rpm. The dispersion time is not particularly limited, but is usually 0.1 to 20 minutes in the case of a batch method. The temperature during dispersion is usually 0 to 150 ° C. (under pressure), preferably 10 to 98 ° C.

  The amount of the aqueous medium used relative to 100 parts of the dispersion is usually 50 to 2000 parts by weight, preferably 100 to 1000 parts by weight. If the amount is less than 50 parts by weight, the dispersion state of the dispersion is poor, and toner particles having a predetermined particle size cannot be obtained. If it exceeds 20000 parts by weight, it is not economical. Moreover, a dispersing agent can also be used as needed. The use of a dispersant is preferable in that the particle size distribution becomes sharp and the dispersion is stable. Dispersants include water-soluble polymers (polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinylpyrrolidone, etc.), inorganic powders (calcium carbonate powder, calcium phosphate powder, hydroxyapatite powder, silica fine powder, etc.) and surfactants ( Nonionic surfactants, anionic surfactants, etc.) can be used. Specific examples of the anionic surfactant include fatty acid soaps such as sodium stearate and sodium dodecanoate, sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, sodium lauryl sulfate and the like. Further, specific examples of nonionic surfactants include polyoxyethylene dodecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene lauryl ether, polyoxyethylene sorbitan monooleate ether, monodecanoyl And sucrose. Further, an emulsion polymerization emulsion obtained by copolymerizing (meth) acrylic acid or the like is also effectively dispersed and stabilized. Examples of the organic solvent in the present invention include compounds having active hydrogen groups (A), compounds having a site capable of reacting with the compound (A) (B), and solvents that can dissolve the binder resin. It can be used, but is preferably volatile with a boiling point of less than 100 ° C. from the viewpoint of easy removal. Examples of the solvent include ethyl acetate, acetone, methyl ethyl ketone, and THF. The amount of the organic solvent used relative to 100 parts of the dispersion is usually 10 to 500 parts, preferably 20 to 400 parts, more preferably 50 to 300 parts. As a method for removing the organic solvent from the toner base particles dispersed in the aqueous medium, a removal technique by heating under a known normal pressure or reduced pressure is used. At this time, the compound (A) having an active hydrogen group of the present invention and the compound (B) having a site capable of reacting with the compound (A) undergo a crosslinking reaction. The toner particle mother liquor is solid-liquid separated by a centrifuge, a spatula filter, a filter press or the like, and the obtained powder is dried to obtain the toner used in the present invention. As a method of drying the obtained powder, it can be carried out using a combination of known equipment such as an airflow dryer, a vibration fluidized dryer, a fluidized bed dryer, a vacuum dryer, and a circulating dryer depending on the case. . Moreover, it can classify | classify using a wind classifier etc. as needed, and can also be set as predetermined particle size distribution.

  The toner used in the present invention can be used together with additives such as a fluidizing agent, if necessary. Specific examples of such fluidizing agents include fine powders such as hydrophobic silica, titanium oxide, and aluminum oxide. Usually, 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight are used with respect to 100 parts by weight of the binder resin.

  Further, the toner used in the present invention includes an inorganic additive such as magnetite, ferrite, cerium oxide, strontium titanate, and conductive titania, a resistance adjuster such as a styrene resin and an acrylic resin, a lubricant, and the like. Used as. The amount of these additives to be used may be appropriately selected depending on the desired performance, and is usually about 0.05 to 10 parts by weight with respect to 100 parts by weight of the binder resin.

  The image forming toner of the present invention may be used in any form of a two-component developer or a non-magnetic one-component developer. When used as a two-component developer, the carrier may be a magnetic substance such as iron powder, magnetite powder, ferrite powder, or a known material such as a mono or magnetic carrier having a resin coating on the surface thereof. As the coating resin of the resin coating carrier, generally known styrene resin, acrylic resin, styrene acrylic copolymer resin, silicone resin, modified silicone resin, fluororesin, or a mixture thereof can be used.

  In order to form a high-resolution image, the volume average particle diameter of the toner is preferably 3 to 8 μm, and more preferably 4 to 7 μm. The particle size distribution is preferably a volume average particle size / number average particle size value of 1.25 or less. From the viewpoint of easily producing such a toner, it is preferable to produce the toner used in the present invention by the above method.

  In the toner used in the present invention, the glass transition point of the toner is usually 40 to 70 ° C., preferably 45 to 55 ° C. If it is less than 40 ° C., the heat-resistant storage stability of the toner deteriorates, and if it exceeds 70 ° C., the low-temperature fixability becomes insufficient. Due to the coexistence of the crosslinked and / or elongated polyester resin, the toner of the present invention tends to have good heat-resistant storage stability even when the glass transition point is low, as compared with known polyester-based toners.

  The method for measuring the glass transition point (Tg) will be outlined. As an apparatus for measuring Tg, a TG-DSC system TAS-100 manufactured by Rigaku Corporation was used. First, about 10 mg of a sample is placed in an aluminum sample container, which is placed on a holder unit and set in an electric furnace. Next, after heating from room temperature to 150 ° C. at a temperature rising rate of 10 ° C./min, the sample was allowed to stand at 150 ° C. for 10 minutes, and then the sample was cooled to room temperature and left for 10 minutes. DSC measurement was performed by heating to 150 ° C. at a heating rate of 10 ° C./min in a nitrogen atmosphere. Tg was calculated from the tangent of the endothermic curve near Tg and the base line using the TAS-100 system.

(D4 / Dn: weight average particle diameter / number average particle diameter)
The toner used in the present invention preferably has a weight average particle diameter (D4) of 3 to 8 μm and a ratio (D4 / Dn) to the number average particle diameter (Dn) of 1.25 or less, preferably 1.05. It is more preferable to be 1.20.

The toner of the present invention preferably has a BET specific surface area of 1.0 to 6.0 (m ² / g), and if the BET specific surface area is less than 1.0 (m ² / g), the presence or addition of coarse particles If the amount exceeds 6.0 (m ² / g), the image quality is likely to be affected by the presence of fine particles, the presence of additives, and surface irregularities.

  The BET specific surface area of the toner used in the present invention can be obtained by measuring using a device capable of complying with JIS standards (Z8830 and R1626) such as NOVA series manufactured by Yuasa Ionics.

  By using such a dry toner, it is excellent in all of heat-resistant storage stability, low-temperature fixability, and hot-offset resistance, particularly excellent in image gloss when used in a full-color copying machine, and further, a two-component developer. In the toner, even if the toner balance for a long period of time is performed, the fluctuation of the toner particle diameter in the developer is reduced, and good and stable developability can be obtained even with long-term stirring in the developing device. Examples of the measuring device for the particle size distribution of toner particles by the Coulter counter method include Coulter Counter TA-II and Coulter Multisizer II (both manufactured by Coulter). The measurement method is described below. First, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added as a dispersant to 100 to 150 ml of the electrolytic aqueous solution. Here, the electrolytic solution is a solution prepared by preparing a 1% NaCl aqueous solution using primary sodium chloride. For example, ISOTON-II (manufactured by Coulter) can be used. Here, 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes, and the measurement device is used to measure the volume and number of toner particles or toner using a 100 μm aperture as an aperture. Volume distribution and number distribution are calculated. From the obtained distribution, the weight average particle diameter (D4) and the number average particle diameter of the toner can be obtained. The channels include: 2.00 to less than 2.52 μm; 2.52 to less than 3.17 μm; 3.17 to less than 4.00 μm; 4.00 to less than 5.04 μm; 5.04 to less than 6.35 μm; .35 to less than 8.00 μm; 8.00 to less than 10.08 μm; 10.08 to less than 12.70 μm; 12.70 to less than 16.00 μm; 16.00 to less than 20.20 μm; Uses 13 channels of less than 40 μm; 25.40 to less than 32.00 μm; 32.00 to less than 40.30 μm, and targets particles having a particle size of 2.00 μm to less than 40.30 μm.

  Hereinafter, the present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto. All parts are parts by weight.

[Production example of polyester resin]
The raw materials shown in Table 1 are placed in a reaction vessel equipped with a cooling tube / stirrer and a nitrogen introduction tube, and further 1 part of dibutyltin oxide and 0.05 part of hydroquinone are added and reacted at 180 ° C. at normal pressure for 8 hours. After that, the temperature was raised to 200 ° C. and the reaction was performed under a reduced pressure of +10 to 15 mmHg until the desired softening point F1 / 2 was reached, thereby synthesizing the desired resin. Table 1 shows the physical properties of the obtained resin.

[Production Example of Isocyanate-Containing Composition]
After pulverizing 11,000 parts of the resin A obtained in the above production example, it was placed in a reaction vessel equipped with a cooling tube / stirrer and a nitrogen introducing tube, and 1200 parts of ethyl acetate was added and dissolved. The mixture was heated to 50 ° C. at normal pressure, 205 parts of isophorone diisocyanate was added and reacted for 2 hours to obtain an ethyl acetate solution B1 of an isocyanate-containing composition.

[Toner Production Example 1]
380 parts of polyester resin A1, 23 parts of carnauba wax, 36 parts of carbon black (Regal 400R manufactured by Cabot), CCA (salicylic acid metal complex E-84: Orient Chemical Industry) in a container equipped with a stir bar and thermometer 5 parts and 517 parts of ethyl acetate were added, the temperature was raised to 80 ° C. with stirring, the temperature was maintained as it was for 5 hours, and then cooled to 30 ° C. in 1 hour. Next, using a bead mill (Ultra Visco Mill, manufactured by Imex Co., Ltd.), this solution is filled with 80% by volume of 0.5 mm zirconia beads at a liquid feed rate of 1 kg / hr disk peripheral speed of 6 m / second, and sufficient for 3 passes. Carbon black and wax were dispersed to obtain a colored organic solvent dispersion. 140 parts of the above isocyanate-modified polyester resin solution B1 was added to this organic solvent dispersion, and the mixture was stirred for 10 minutes with a stirring motor. Further, 7 parts of N-behenyl-1,3-propyldiamine was added and stirred for 5 minutes.

  Next, 1050 parts deionized, 7.6 parts sodium dodecylbenzene sulfonate, 2.6 parts sodium dodecyl diphenyl ether disulfonate, 2.5 parts carboxymethyl cellulose (Serogen BSH manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) in a separate container. Were mixed and stirred to obtain an aqueous solution.

  Next, the colored organic solvent dispersion was added to the aqueous solution, and mixed with a TK homomixer (manufactured by Tokushu Kika) at a rotational speed of 13,000 rpm for 30 minutes to obtain a toner base particle dispersion. The toner mother particle dispersion was charged into a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. for 8 hours, followed by aging at 50 ° C. for 15 hours to obtain a toner slurry. Toner 1 was obtained by filtering and drying the toner from the slurry. The volume average particle diameter of the toner was 4.7 μm (measured with a multisizer). To 100 parts of this toner, 1.5 parts of hydrophobized silica (R-972 manufactured by Nippon Aerosil Co., Ltd.) was added using a Henschel mixer to make an evaluation sample.

[Production Examples 2 to 7]
As shown in Table 2, toner was prepared in the same manner as in Toner Production Example 1 by changing the polyester resin, wax, and the like.

[Production Example 8]
Toner 8 was obtained in the same manner as in Example 1, except that N-behenyl-1,3-propyldiamine was changed to isophoronediamine.

[Production Example 9]
Toner 9 was obtained in exactly the same manner as in Example 1, except that N-behenyl-1,3-propyldiamine was changed to a methyl ethyl ketone-isophoronediamine ketimine compound.

[Evaluation item]
A method for evaluating the characteristics of the toner prepared in each production example will be described.

(Particle size)
The particle diameter of the toner was measured using a particle size measuring device “Coulter Counter TAII” manufactured by Coulter Electronics Co., Ltd., with an aperture diameter of 100 μm. The volume average particle size and the number average particle size were determined by the particle size measuring instrument.

(Charge amount measurement method)
Adjust the developer with Powder Tech FL-100 as a carrier and toner to a toner concentration of 5%, stir in a ball mill for 1 hour, weigh 6g of developer, charge it into a metal cylinder that can be sealed and blow to charge. Find the amount.

(Evaluation of storage stability)
A glass container is filled with toner and left in a thermostatic bath at 50 ° C. for 24 hours. The toner is cooled to 24 ° C., and the penetration is measured by a penetration test (JIS K2235-1991). A toner having a larger value has better storage stability against heat. When this value is 5 mm or less, there is a high possibility of problems in use.

  Judgment criteria for thermal storage stability based on the penetration is as follows.

◎: penetration, ○: 25 mm or more, □: 20 to 25 mm, Δ: 15 to 20 mm, x: less than 15 mm
(Tg measurement method)
Using a TG-DSC system TAS-100 manufactured by Rigaku Corporation, the sample was heated to about 10 mg from room temperature to 150 ° C. at a heating rate of 10 ° C./min, then left at 150 ° C. for 10 minutes, and the sample was cooled to room temperature to 10 The DSC measurement was carried out by standing for a minute and heating to 150 ° C. again at a heating rate of 10 ° C./min in a nitrogen atmosphere. Tg was calculated from the point of contact with the tangent baseline of the endothermic curve near Tg using the analysis system in the TAS-100 system.

（定着ベルトの作製）
ポリイミドからなる厚さ９０μｍの円筒状のエンドレスフィルム基体の外周に，プライマー（東レ・ダウコーニングシリコーン社製ＤＹ３９−０６７）をスプレーコートにて厚さ４μｍで成膜し，室温乾燥した。その後，２液付加型液状シリコーンゴム（東レ・ダウコーニングシリコーン社製ＤＹ３５−２０８３）を２液混合後に、トルエンにて適量希釈し、スプレーコートにて厚さ２００μｍで塗布，１２０℃１０分硬化後、さらに２００℃４時間２次硬化して弾性層を形成した。

(Fixing belt production)
A primer (DY39-067 manufactured by Dow Corning Toray Co., Ltd.) was formed on the outer periphery of a cylindrical endless film substrate made of polyimide with a thickness of 90 μm by spray coating and dried at room temperature. Thereafter, two-component addition type liquid silicone rubber (DY35-2083 manufactured by Toray Dow Corning Silicone Co., Ltd.) is mixed with two components, diluted with toluene in an appropriate amount, applied by spray coating to a thickness of 200 μm, and cured at 120 ° C. for 10 minutes. Further, secondary curing was performed at 200 ° C. for 4 hours to form an elastic layer.

  Subsequently, a primer (PR-990CL manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) was spray-coated at a thickness of 4 μm and then dried at 150 ° C. for 30 minutes.

  Thereafter, a PFA (Mitsui-Ki), with an MFR (measurement standard JIS K 7210) at 372 ° C. and a load of 5 kgf of 3 [g / 10 min], an average particle diameter of 10 μm and an oxygen atom number / carbon atom ratio in the molecular chain of 1/60. PFA-950HP • Plus manufactured by DuPont Fluorochemical Co.), MFR (measurement standard JIS K 7210) at 372 ° C. and 5 kgf load is 7 [g / 10 min], the average particle size is 0.1 μm, and the number of oxygen atoms in the molecular chain / A mixed dispersion in which PFA having a carbon atom ratio of 1/60 (PFA-945HP • Plus manufactured by Mitsui DuPont Fluoro Chemical Co., Ltd.) was mixed at 1/1 was spray-coated at a thickness of 30 μm. Thereafter, firing was performed at 340 ° C. for 30 minutes (melting PFA particles) to form a release layer, and [Fixing belt 1] was obtained.

(Fixing belt production)
A primer (DY39-067 manufactured by Toray Dow Corning Silicone Co., Ltd.) was formed on the outer periphery of a cylindrical endless film substrate made of polyimide with a thickness of 90 μm by spray coating and dried at room temperature. Thereafter, two-component addition type liquid silicone rubber (DY35-2083 manufactured by Toray Dow Corning Silicone Co., Ltd.) is mixed with two components, diluted with toluene in an appropriate amount, applied by spray coating to a thickness of 200 μm, and cured at 120 ° C. for 10 minutes. Further, secondary curing was performed at 200 ° C. for 4 hours to form an elastic layer.

  Subsequently, a primer (PR-990CL manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) was spray-coated at a thickness of 4 μm and then dried at 150 ° C. for 30 minutes.

  Thereafter, a PFA with an MFR (measurement standard JIS K 7210) of 7 [g / 10 min] at 372 ° C. and a load of 5 kgf and an average particle size of 0.1 μm and a PFA with an average particle size of 10 μm (PFA manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) 945HP · Plus) mixed at 1/1, was spray coated with a thickness of 30 μm. Thereafter, firing was performed at 340 ° C. for 30 minutes (melting PFA particles) to form a release layer, and [Fixing belt 2] was obtained.

(Examples and Comparative Examples)
Evaluation was performed using the toner and the fixing belt according to the above-described production example.

  The toner / fixing belt combinations in the examples and comparative examples are as follows.

（定着性）
普通紙及び厚紙の転写紙（リコー製タイプ６２００及びＮＢＳリコー製複写印刷用紙＜１３５＞）にベタ画像で、１．０±０．１ｍｇ／ｃｍ^２のトナーが現像される様に調整を行ない、定着ベルトの温度が可変となる様に調整を行なって、普通紙でオフセットの発生しない温度を、厚紙で定着下限温度を測定した。定着下限温度は、得られた定着画像をパットで擦った後の画像濃度の残存率が７０％以上となる定着ロール温度をもって定着下限温度とした。

(Fixability)
Make adjustments so that 1.0 ± 0.1 mg / cm ² of toner is developed with a solid image on plain paper and cardboard transfer paper (Ricoh Type 6200 and NBS Ricoh Copy Printing Paper <135>), Adjustment was made so that the temperature of the fixing belt was variable, and the temperature at which no offset occurred on plain paper and the minimum fixing temperature on thick paper were measured. The lower limit fixing temperature was determined as the fixing lower limit temperature at the fixing roll temperature at which the residual ratio of the image density after rubbing the obtained fixed image with a pad was 70% or more.

The evaluation conditions for low-temperature fixing are a paper feed linear velocity of 120 to 150 mm / sec, a surface pressure of 1.2 kgf / cm ² , a nip width of 3 mm, and the high temperature offset evaluation conditions are a paper feed linear velocity of 50 mm / sec, The surface pressure was set to 2.0 kgf / cm ² and the nip width was 4.5 mm.

(1) Low temperature fixability (five-level evaluation)
A: Less than 120 ° C., O: 120 to 130 ° C., □: 130 to 140 ° C., Δ: 140 to 150 ° C., X: 150 ° C. or higher (2) Hot offset property (five-step evaluation)
A: 201 ° C. or higher, ○: 200 to 191 ° C., □: 190 to 181 ° C., Δ: 180 to 171 ° C., x: 170 ° C. or lower
(Flexibility)
The fixing belt described above was incorporated in the fixing device, and the cracks in the release layer were visually confirmed after outputting 300,000 sheets.

The fixing conditions at the time of output are plain paper (Ricoh type 6200) with a solid image, adjusted so that 1.0 ± 0.1 mg / cm ² of toner is developed, and the linear speed of paper feed is 120 to 150 mm. / Sec, 1.2 kgf / cm ² , nip width 3 mm, fixing roll temperature: each toner fixing lower limit temperature + 20 ° C.

Flexibility (three-step evaluation)
○: No crack, △: Cracked but slight, ×: Crack leading to abnormal image

実施例の結果から、特に、定着部材のフッ素樹脂は、３７２℃，５ｋｇｆ荷重におけるＭＦＲが７［ｇ／１０ｍｉｎ］以上のフッ素樹脂と、３７２℃，５ｋｇｆ荷重におけるＭＦＲが３［ｇ／１０ｍｉｎ］以下のフッ素樹脂とからなる定着ベルト１と、トナー１乃至７とを使用して行った実施例１乃至７が、良好な画像形成となった。

From the results of the examples, in particular, the fluororesin of the fixing member is a fluororesin having an MFR of 7 [g / 10 min] or more at 372 ° C. and 5 kgf load, and an MFR of 3 [g / 10 min] or less at 372 ° C. and 5 kgf load. Examples 1 to 7 using the fixing belt 1 made of the above fluororesin and the toners 1 to 7 produced good image formation.

  Therefore, according to the present invention, it is possible to obtain an image forming method capable of low-temperature fixing, good initial print quality, and excellent image quality stability in continuous printing.

  Further, the present invention employs the above image forming method, at least an image carrier, toner image forming means for forming a toner image on the image carrier, and the toner image on the image carrier as a transfer material. It is possible to provide an image forming apparatus including a transfer unit that transfers and a fixing unit that fixes a toner image on the transfer material.

  Although the embodiments of the present invention have been specifically described above, the present invention is not limited to these embodiments, and these embodiments of the present invention depart from the spirit and scope of the present invention. And can be changed or modified.

1 is a schematic diagram illustrating an image forming apparatus using a fixing member (fixing belt) according to an exemplary embodiment. 1 is a schematic diagram illustrating a fixing device using a fixing member (fixing belt) of the present embodiment. FIG. 4 is a cross-sectional view of a fixing member (fixing belt). (A) is schematic explanatory drawing of the fluororesin particle adhering to an elastic layer when forming a release layer with a thickness of 20 μm or less, and (b) is when forming a release layer with a thickness of 20 μm or more It is a schematic explanatory drawing of the fluororesin particle adhering to this elastic layer. It is the graph which investigated the bending resistance of PFA whose oxygen atom number / carbon atom number ratio in a molecular chain is 1/60 or more, and PFA whose oxygen atom number / carbon atom number ratio in a molecular chain is 1/100 or less. .

Explanation of symbols

1Y, 1M, 1C, 1Bk photoconductor drum 2Y, 2M, 2C, 2Bk charger 3Y, 3M, 3C, 3Bk exposure unit 4Y, 4M, 4C, 4Bk development unit 5Y, 5M, 5C, 5Bk transfer unit 6Y, 6M, 6C, 6Bk Photoconductor cleaner 7 Driving roller 10Y, 10M, 10C, 10Bk Image forming unit 20 Conveying belt 40 Fixing device 41 Fixing roller 42 Pressure roller 43 Spring 44 Heating roller 45 Fixing belt 46 Halogen lamp 47 Tension roller 48 Spring 49 Thermistor 50 Paper Tray 451 Film Base 452 Elastic Layer 453 Release Layer P Transfer Paper

Claims (16)

In an image forming method in which an electrostatic latent image formed on an image carrier is visualized as a toner image by a developing unit, and the toner image is transferred and fixed on a transfer material.
A fixing member in which the outermost layer of the fixing member is made of fluororesins having different melt mass flow rates (according to JIS K6935-1 melt mass flow rate conditions) at 372 ° C. and 5 kgf load;
At least the compound (A) having an active hydrogen group, the compound (B) having a site capable of reacting with the compound (A), a colorant, and a release agent are dissolved or dispersed in an organic solvent, and the solution or dispersion is dissolved. It is obtained by dispersing the liquid in an aqueous medium and reacting the polymer having a site capable of reacting with the compound having an active hydrogen group, or after reacting, removing the organic solvent, washing and drying. Use toner and
The compound (A) is represented by the following general formula H2N—R—NH—R ′
R is saturated alkyl, C2 to C6
R ′ is saturated or unsaturated alkyl, C8 to C24
An image forming method characterized by the following.   The fixing member includes a fluororesin having a melt mass flow rate at 372 ° C. and a load of 5 kgf (based on JIS K6935-1 melt mass flow rate) of 7 [g / 10 min] or more and a melt resin at a load of 372 ° C. and a load of 5 kgf. 2. The image forming method according to claim 1, comprising a fluororesin having a mass flow rate (based on JIS K6935-1 melt mass flow rate conditions) of 3 [g / 10 min] or less.   The image forming method according to claim 1, wherein the fluororesin of the fixing member is made of a plurality of types of fluororesins having different particle sizes.   Among the fluororesins, the particle size of the fluororesin having the larger melt mass flow rate (conforming to the conditions of JIS K6935-1 melt mass flow rate) is the same as the melt mass flow rate of the fluororesin (JIS K6935-1 melt mass flow rate). 4. The image forming method according to claim 3, wherein a fixing member smaller than the particle diameter of the smaller fluororesin is used.   5. A fixing member comprising 35 to 60% by weight of a fluororesin having a larger melt mass flow rate (based on JIS K6935-1 melt mass flow rate conditions) among the fluororesins is used. The image forming method according to claim 1.   Of the fluororesins, the one having the larger melt mass flow rate (according to the conditions of JIS K6935-1 melt mass flow rate) and the larger one of the fluororesins, the melt mass flow rate (according to the conditions of JIS K6935-1 melt mass flow rate) The image forming method according to claim 1, wherein a fixing member having a mixing ratio with a smaller fluororesin of 1: 1 is used.   7. The image forming method according to claim 1, wherein a fixing member in which the fluororesin is a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin (PFA) is used.   The tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer resin (PFA) uses a fixing member having a ratio of the number of oxygen atoms / the number of carbon atoms in a molecular chain of 1/60 or more. 8. The image forming method according to 7.   9. The image forming method according to claim 1, wherein a fixing member having a thickness of the outermost layer of 20 [mu] m or more is used.   The image forming method according to any one of claims 1 to 9, wherein a toner in which a site capable of reacting with the compound (A) having an active hydrogen group of the compound (B) is an isocyanate group is used.   10. The image forming method according to claim 1, wherein a toner capable of reacting with the compound (A) having an active hydrogen group of the compound (B) is an epoxy group. 11.   The image forming method according to claim 1, wherein the toner has a weight average particle diameter of 3 to 8 μm.   13. The image forming method according to claim 1, wherein the toner has a weight average particle diameter / number average particle diameter of 1.25 or less.   The image forming method according to claim 1, wherein the toner has a glass transition point of 40 ° C. to 70 ° C. The image forming method according to any one of claims 1 to 9, 10 and / or 11, 12 to 14, wherein the toner has a BET specific surface area of 1.0 to 6.0 m ² / g.   At least an image carrier, a toner image forming unit that forms a toner image on the image carrier, a transfer unit that transfers a toner image on the image carrier to a transfer material, and a toner image on the transfer material An image forming apparatus comprising a fixing unit for fixing, wherein the image forming apparatus uses the image forming method according to any one of claims 1 to 9, 10 and / or 11, 12 to 15.

Images