JPH06289651A - Developer for heat fixing and image forming method - Google Patents

Abstract

PURPOSE:To provide the developer for heat fixing which stabilizes offset resistance and developing property and prevents fixing of the developer onto the surface of an electrostatic charging member or sleeve. CONSTITUTION:This developer is used in the image forming method having a stage for executing electrostatic charge by bringing an electrostatic charging roller 32 into contact with a photosensitive drum 31 from the outside and impressing a voltage E from the outside, a cleaning stage for removing the developer from a photosensitive drum 31 and a fixing stage for heat fixing the sensible image of the developer onto a recording material. The developer mentioned above contains at least a binder resin, coloring agents and metal-contg. compd. The chromatogram measured by GPC of the binder resin has at least one max. value in the respective regions of 2,000 to 30,000 and 800,000 to 3,000,000 mol.wt. and only the polymer constituting the high-polymer side max. value has a polar group capable of forming crosslinked bonds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic printing,
The present invention relates to a heat fixing developer and an image forming method in magnetic recording and the like.

[0002]

2. Description of the Related Art Conventionally, as a method for fixing a visible image of a developer (toner) on a recording material, a heating roller which is maintained at a predetermined temperature and a pressure roller which has an elastic layer and is brought into pressure contact with the heating roller. Therefore, a heat roll fixing method is widely used in which a recording material holding an unfixed toner visible image is heated while being nipped and conveyed. Further, a belt fixing method described in USP 3,578,797 is known. However,
In the above-described heat roller fixing which has been frequently used, there is a so-called wait time (1) the time during which the image forming operation is prohibited until the heat roller reaches a predetermined temperature.

(2) Optimum temperature of the heating roller in order to prevent fixing failure and transfer of toner to the heating roller due to fluctuations in the temperature of the heating roller due to passage of a recording material or other external factors, so-called offset phenomenon. Therefore, it is necessary to increase the heat capacity of the heating roller or the heating body for this purpose, which requires a large amount of electric power and causes a temperature rise inside the image forming apparatus.

(3) Since the pressure roller has a lower temperature than the fixing roller, the recording material and the toner on the recording material are cooled slowly when the recording material is discharged through the heating roller. The toner may have a high adhesiveness, and the offset or the jam of the recording material may occur due to the curvature of the roller.

(4) Since the high-temperature heating roller comes into direct contact with the hand, there is a problem in safety or a protective member is required.

Further, in the belt fixing method described in USP 3,578,797, the problems (1) and (2) of the heat roll fixing described above have not been fundamentally solved.

Japanese Patent Application Laid-Open No. 63-313182
In the publication, a toner image is heated through a heat-resistant sheet that is moved by a low-heat-capacity heating element that is energized and heated in a pulse shape, and a fixing device that fixes the toner image on a recording material has a short wait time and low power consumption. Forming devices have been proposed. In addition, similarly, Japanese Patent Application Laid-Open No. 1-18
Japanese Patent No. 7582 discloses a fixing device that heats and fixes a visible image of toner on a recording material via a heat resistant sheet.
A fixing device has been proposed in which the heat-resistant sheet has a heat-resistant layer and a release layer or a low resistance layer to effectively prevent the offset phenomenon.

However, in order to realize a fixing method that has a short wait time and low power consumption while achieving excellent fixability of a toner image on a recording material, prevention of offset, etc., the above-mentioned fixing device is used. In addition to this, the characteristics of the toner largely depend.

Conventionally, in order to prevent the toner from adhering to the surface of the fixing roller, a method of adding a wax such as low-molecular-weight polyethylene or polypropylene, which is sufficiently melted when heated, has been used in order to increase the releasability of the toner. ,
While it is effective in preventing offset, it tends to cause deterioration in durability due to increased toner cohesiveness, unstable charging characteristics. Therefore, as other methods, various attempts have been made to improve the binder resin.

For example, a method of increasing the glass transition temperature (Tg) and the molecular weight of the binder resin in the toner and improving the melt viscoelasticity of the toner is also known. However, in such a method, when the offset phenomenon is improved, the fixability becomes insufficient, and there arises a problem that the fixability at a low temperature required for high-speed development and energy saving, that is, the low-temperature fixability is deteriorated. .

Generally, in order to improve the low temperature fixability of the toner, it is necessary to lower the viscosity of the toner at the time of melting to increase the adhesion area with the fixing substrate. For this reason, the Tg and molecular weight of the binder resin used Is required to be low.

That is, since the low-temperature fixing property and the offset preventing property are contradictory to each other, it is very difficult to develop a toner satisfying these functions at the same time.

In order to solve this problem, for example, Japanese Patent Publication No. 51-23354 discloses a toner made of a vinyl polymer which is appropriately crosslinked by adding a crosslinking agent and a molecular weight adjusting agent. 6805 discloses a toner having a wide molecular weight distribution such that the ratio of the weight average molecular weight to the number average molecular weight of an α, β unsaturated ethylenic monomer as a constituent unit is 3.5 to 40, and Has proposed a blend type toner in which Tg, molecular weight, gel content and the like are combined in a vinyl polymer.

Certainly, the toners according to these proposals have a lower fixing temperature (the lowest fixing temperature) and an offset temperature (the temperature at which offset begins to occur), as compared with a toner made of a single resin having a narrow molecular weight distribution. However, if sufficient offset prevention performance is given, the fixing temperature cannot be lowered sufficiently, and if low temperature fixability is emphasized, the offset prevention performance will be insufficient. There was the problem of becoming.

Further, in place of these vinyl resins, a toner obtained by crosslinking a polyester resin which is essentially superior to vinyl resins in terms of low-temperature fixability and further adding an offset preventive agent is also special. Kaisho 57-20855
No. 9 publication. This product is excellent in both low-temperature fixing property and anti-offset property, but it has a problem in productivity as a toner (grindability).

Further, in JP-A-56-116043, a vinyl monomer is polymerized in the presence of a reactive polyester resin and polymerized through a crosslinking reaction, an addition reaction and a grafting reaction in the course of the polymerization. Although a toner using such a resin has been proposed and improved in terms of pulverizability, mutual resin functions cannot be fully utilized in terms of low-temperature fixability and offset prevention.

Further, two kinds of gel contents which are simply different from polyester resin (gelation degree of 80% or more and gelation degree of 1
A toner using a resin blended with a vinyl-based resin (less than 0%) is proposed in Japanese Examined Patent Publication No. 1-15063. Although this toner has good low-temperature fixability, it has offset resistance and pulverizability. Not enough yet. If the proportion of the vinyl resin having a gelation degree of 80% or more is increased for the purpose of improving the offset resistance, the offset prevention property is improved, but the low temperature fixing property is remarkably lowered. Also, gelation degree 1
Sufficient grindability cannot be satisfied only by containing less than 0% of vinyl resin.

On the other hand, with respect to the physical properties required for the toner as described above, crosslinking is carried out by reacting a polymer having a carboxylic acid with a metal compound in the binder resin (JP-A-57-57). 178249, 57-17
No. 8250), or a binder containing a vinyl-based resin monomer and a more specific monoester compound as an essential constituent unit and a polyvalent metal compound, and crosslinks via a metal (Japanese Patent Laid-Open No. 61- 110155, 61-110
No. 156) is introduced.

Further, JP-A-63-214760, 63-217362, 63-217363, and 6
In Japanese Patent Laid-Open No. 3-217364, 2 of low molecular weight and high molecular weight is used.
It has a molecular weight distribution divided into groups and crosslinks by reacting carboxylic acid groups contained on the low molecular weight side with polyvalent metal ions (adding a dispersion of a metal compound to a solution obtained by solution polymerization and heating it. However, the reaction between the binder and the metal compound or the dispersion of the metal compound in the binder is not sufficient in any of the methods, and the physical properties required for the toner, particularly the fixing Properties and offset resistance have not yet been satisfied. Moreover, since it is necessary to mix a large amount of the metal compound with the binder resin, the mixed metal compound exhibits a catalytic action on the binder resin depending on the conditions, and the binder resin easily gels. As a result, the metal compound is mixed. Therefore, it is difficult to determine the manufacturing conditions for obtaining the desired toner, and even if the manufacturing conditions can be determined, it is difficult to obtain reproducibility.

Further, JP-A-2-168246 and JP-A-2-168246
No. 235069, further polarization of a low molecular weight component and a high molecular weight component in a binder resin, and a carboxyl group contained in the high molecular weight component improve the offset resistance and prevent the toner from being produced during toner production. It is disclosed that the deterioration of developability due to the pulverization phenomenon is prevented, but as a result of our investigation, it was described in the specification that the performance is improved with respect to fixing property and offset resistance. With such an amount of acid, the dispersed state of each constituent component inside the developer including the binder resin becomes insufficient, uneven distribution of each component inside the developer and release to the outside of the developer, It becomes difficult to obtain stable developability.

In recent years, small-sized and inexpensive personal-use copying machines and laser printers have appeared, and it is more important for such a small machine to save space and reduce power consumption, and the fixing device is further downsized. It is necessary to simplify the structure and reduce power consumption. The fixing device of the present invention has a small size and a low heat capacity, and is suitable for such a purpose. However, in order to fully exhibit this feature of the fixing device, the developer is required to exhibit sufficient fixing property at low pressure and low heat quantity. Along with this, the binder resin of the developer is mainly composed of a soft component having a low softening point and melt viscosity. When such a binder resin is used, the cohesiveness of the developer becomes high. Furthermore, when the raw materials are melt-kneaded, sufficient shearing force cannot be obtained, and there is a high possibility that the above-mentioned constituent components will be poorly dispersed.

When a developer having such a high cohesive property and poor dispersion is used in the contact transfer device of the present invention, a very serious problem occurs.

Electrostatic latent image carrier (photoreceptor) during transfer
When pressure is applied between the developer developed above and the transfer material, the developer particles having a very soft portion locally due to poor dispersion agglomerate and are not transferred, and conversely strongly on the photoreceptor. It will stick. As a result, the resulting image has partial defects. In particular, a transfer failure occurs in a line or a central portion of a character where pressure is likely to be concentrated, resulting in a so-called hollow image.

Moreover, the developer remaining on the photoconductor is often not completely removed even in the cleaning step.
While the particles are gradually deposited and accumulated to cause large defects on the image, there is a high possibility that the surface of the photoconductor will be damaged in the portion where the hard component is concentrated, which also causes image defects.

Further, when the developer in such a state is used in the heat fixing method having the fixing film applied to the present invention, problems such as sticking to the fixing film and breakage of the fixing film occur.

As a result of intensive studies conducted by us, this phenomenon becomes more remarkable as the weight average molecular weight (Mw) / number average molecular weight (Mn), which is considered to indicate the degree of polarization of the binder resin, increases. In particular, when Mw / Mn ≧ 20, the fixing property and the offset resistance can be satisfied to some extent, but a serious problem occurs in the matching with the developing property and the fixing method as described above.

The various performances required for the toners listed above are often reciprocal with each other, and it has been increasingly desired in recent years to satisfy both of them with high performance. Although there has been research on comprehensive comprehensive responses, there is still not enough.

On the other hand, conventionally, a corona discharger has been known as a charging means in an electrophotographic apparatus or the like. However, the corona discharger has problems that a high voltage must be applied and that the amount of ozone generated is large.

Therefore, recently, it has been considered to use the contact charging means without using the corona discharger. Specifically, a voltage is applied to a conductive roller, which is a charging member, to bring the roller into contact with a photosensitive member, which is a member to be charged, to charge the surface of the photosensitive member to a predetermined potential. If such a contact charging means is used, the voltage can be lowered and the amount of ozone generated can be reduced as compared with the corona discharger.

However, when the above contact charging means is used, there is a problem that charging failure occurs if sufficient contact with the member to be charged cannot be maintained. Further, if residual developer is present on the surface of the photoconductor at the contact portion, the residual developer adheres to the surface of the charging member and the photoconductor because the charging member has a predetermined contact pressure, and the image is affected. I also have problems.

On the other hand, in the small machine as described above,
From a maintenance-free standpoint, a cartridge system in which a photoreceptor, a developing device, a cleaning device, etc. are integrated is used, and it is desirable to use a magnetic one-component developer as the developer because the structure of the developing device can be simplified. Be done. Further, these developers tend to be made finer in order to achieve high image quality.

In such a magnetic developer, the developer itself has a strong polishing effect, and the surface of the photoconductor is strongly rubbed during image formation, so that the surface of the photoconductor is often scraped or scratched. There is a problem that the residual developer may be fused due to the cause. This problem remarkably appears when an abutting member such as the charging member that is in contact with the surface of the photoconductor with a predetermined abutting pressure is used.

Further, in the contact charging device according to the present invention, the charging member is applied with a DC voltage or a voltage in which an AC voltage is superimposed on the DC voltage, and at this time, in the vicinity of the contact portion between the charging member and the photosensitive drum, Abnormal charging of the residual developer and repeated flight motions are repeated, which makes it easier to electrostatically attract or embed the residual developer to the surface of the charging member or the photosensitive drum. This is very different from the case of using a non-contact charging means.

Furthermore, in the heat fixing device according to the present invention, a binder resin having a lower viscosity is desired in order to realize heat fixing with a low heat capacity. When the developer containing such a binder resin is used in the contact charging device according to the present invention, fusion or embedding of the residual developer is more likely to occur.

It was difficult to achieve all the properties desired for the developer in the image forming method having such a charging step and a fixing device.

On the other hand, for example, a developing device that visualizes a latent image formed on the surface of a photosensitive drum as an electrostatic latent image carrier with a magnetic toner as a one-component developer, causes friction between magnetic toner particles, And friction between the sleeve as the developer carrying member and the magnetic toner particles gives the magnetic toner particles an electric charge having a polarity opposite to that of the electrostatic image charge formed on the photosensitive drum.
The magnetic toner is applied very thinly on the sleeve and is conveyed to a developing area formed by the photosensitive drum and the sleeve, and the magnetic toner is caused to fly by the action of a magnetic field by a magnet fixed in the sleeve in the developing area to cause the magnetic toner to fly. It is known to visualize the electrostatic latent image of.

However, in each of the developing devices as described above, a relatively thin and uniform toner layer must be formed on the sleeve, but depending on the environmental conditions, the physical properties of the toner, the condition of the sleeve surface, etc. It is not possible to obtain a good toner layer, and unevenness often occurs especially in a low humidity environment.

Further, as the copying is repeated, the developer is repeatedly rubbed with the sleeve, and as a result, additives for improving the fluidity of the toner and non-developing substances such as carriers in the two-component developer are deposited on the sleeve. Or, the surface condition of the sleeve changes because the binder resin in the developer forms a film on the sleeve, and the developability of the developer becomes unstable,
Alternatively, there is a problem that the conveyance of the developer to the electrostatic latent image surface becomes unstable.

In order to prevent such a change in the surface condition of the sleeve, for example, a coating layer containing an inorganic polymer carbon fluoride is formed (JP-A-57-66443), and silica is dispersed. At least one selected from the group consisting of a resin that forms a resin having good releasability (Japanese Patent Laid-Open No. 58-178380), an organic silicone polymer, an aliphatic fluorine-containing compound, a styrene resin, and polyphenylene oxide, and 2 To form a film containing a metal complex having a hexadentate ligand (JP-A-57-76558)
Japanese Patent Laid-Open Publication No. 2003-242242, etc., there has been proposed a method for preventing the change of the surface condition by coating the surface of the sleeve with a substance having a particularly high releasability.

However, in the coated sleeve in which the surface of the sleeve is coated with the synthetic resin or the like, compared with the conventionally used sleeve made of aluminum or SUS,
Relatively obviously soft. Therefore, the developer is pressed during repeated development operations, which is remarkable especially in the case of a magnetic developer containing a magnetic material, but the surface of the developer carrier is subjected to uneven polishing or scratches. However, there is a problem in that the performance originally possessed by the coated sleeve is apt to be deteriorated due to the formation of stains or the deposition of a part of the developer.

On the other hand, the developer is fixed on the transfer material by heat fusion fixing by a heat roller or radiant heating, pressure fixing by a pressure roller, etc., but the heat quantity and pressure are economical and safety / design of the apparatus structure. In consideration of easiness, it is preferable that the amount is small, and accordingly, the components of the developer tend to include so-called soft components such as low melt viscosity, low melting point, and low pressure yield point. On the contrary, in terms of durability and fixing offset, it is also important that the developer contains a hard component.

In order to satisfy such contradictory factors, it is often advantageous that the binder resin constituting the developer contains both a soft portion and a hard portion in its molecular weight distribution.

Further, in order to improve the low temperature fixing property of the toner, it is necessary to lower the viscosity of the toner at the time of melting and to increase the adhesion area with the fixing base material. Lower molecular weight is required.

That is, such a tendency of the developer increases the above-mentioned problems of the developer carrier, and the low-temperature fixing property and the durability of the coat sleeve have opposite sides.

Further, recently, in order to obtain a high-quality image, the particle size of the developer tends to be small, and in the image forming apparatus using the developer having such a small particle size, the developer carrying member is used. When a DC voltage or a DC voltage superimposed with an AC voltage is applied between the photosensitive drum and a latent image bearing member such as a photoconductor drum, the number of times of repeated flight and rubbing of the developer increases in the development area. Therefore, the developer is firmly fixed or embedded on the surface of the coat sleeve, and further, the developer and the developer carrier are easily contaminated with each other, and it is highly possible that the above-mentioned problems of the developer carrier become more remarkable. It is difficult to develop a toner that is extremely large and satisfies these functions at the same time.

[0046]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and charge by contact charging means to achieve excellent fixability, offset resistance and developability, while having a low heat capacity. To provide a developer for heat fixing capable of realizing heat fixing by means of heat and high durability without causing problems such as sticking to a contact charging member, and an image forming method using the developer. It is in.

An object of the present invention is to provide a heat fixing developer which can be uniformly carried on the surface of a sleeve, and an image forming method using the developer.

An object of the present invention is that the wait time is substantially short or extremely short, the power consumption is low, the offset phenomenon does not occur, and the fixing of the developer image on the recording material is good. A fixing developer and a heat fixing method using the developer are provided.

The object of the present invention is that in the image forming method having the transfer step according to the present invention, the image does not have a hollow image and the developer is fixed on the surface of the photoconductor or is scratched. It is an object of the present invention to provide a heat fixing developer and an image forming method that prevent the occurrence of image defects.

[0050]

Means and Actions for Solving the Problems The present inventors have
As a result of diligent studies, by specifying the molecular weight of the binder resin made of a polymer and the polar group capable of forming a cross-linking bond, the polymer has a very wide fixing temperature range and the reproducibility of fine lines. Therefore, the present invention has been completed by finding that excellent and stable, developed images can be formed.

That is, the developer according to the present invention is a binder resin,
The binder resin contains a colorant and a metal-containing compound, and the chromatogram of the binder resin measured by GPC has at least one local maximum in the respective regions of molecular weights of 2,000 to 30,000 and 300,000 to 3,000,000. Has a value and
A polymer having at least a maximum value on the high molecular weight side has a polar group capable of forming a crosslink, and is preferably used in the image forming method having the following constitution.

(1) An image forming method comprising a step of bringing a charging member into contact with an object to be charged from the outside and applying a voltage from the outside to perform charging, and a cleaning step of removing a developer from the object to be charged. .

(2) Development by the above-mentioned charging step and cleaning step, and further by a fixedly supported heating element and a pressing member which is in pressure contact with the heating element and is in close contact with the heating element via a film. An image forming method comprising a fixing step of heating and fixing a visible image of an agent on a recording material.

(3) A resin layer containing at least conductive fine particles is provided on the surface thereof, and a developer whose weight loss on heating up to 300 ° C. of the resin layer is 2% by weight or less of the total weight of the resin layer is carried. An image forming method using a developing device having a developer carrier for transporting.

(4) In the process of developing the electrostatic charge image on the photoconductor with a developer and electrostatically transferring it to the transfer material via the transfer device, the photoconductor and the transfer device are operated at a linear pressure of 3 g / cm or more. An image forming method using a transfer device in contact.

(5) By the above-mentioned transfer step, and further, by the fixedly supported heating body and the pressing member which is in pressure contact with the heating body and is brought into close contact with the heating body via the film, An image forming method having a fixing step of heating and fixing a visible image on a recording material.

The present inventors believe that the developer according to the present invention exhibits the effects of the present invention as follows.

That is, by adding a reactive polar group only to the polymer-side component such as the binder resin of the developer according to the present invention, the heat-melt kneading step at the time of producing the developer is carried out, whereby the metal-containing metal A sufficient crosslinking reaction with the compound is carried out. Especially when a binder resin having a low melt viscosity is used, each component constituting the developer can enjoy the shearing force stronger and more uniformly than ever before due to the thickening effect by the crosslinking reaction.
Not only is the dispersibility improved synergistically and the anti-offset property and the developability are more stabilized than ever, but also in the heat fixing method having the fixing film used in the present invention, good I think it shows matching.

The resulting cross-linking component has the effect of preventing sticking to the charging member in the charging step, preventing sticking and embedding of the developer on the surface of the coat sleeve, and further preventing mutual contamination with the developer carrier. We believe that even if a contact transfer device is used, there will be no omission during transfer, sticking to the photoconductor, or scratches.

Further, by minimizing the reactive polar group on the low molecular weight side, the competitiveness of the low molecular weight component in the crosslinking reaction can be suppressed and only the high molecular weight component can be crosslinked efficiently. Deterioration of fixability due to cross-linking and careless addition of metal-containing compounds are prevented, enabling further low-temperature fixability and stabilization of developability. It is believed that the developer of the present invention can be obtained without causing the developer to stick or scratch.

The above-mentioned effects become more remarkable as the molecular weight distribution of the binder resin is polarized into a high molecular weight component and a low molecular weight component. In particular, when the maximum value of the molecular weight of the polymer side component exceeds 300,000, the mobility in the binder resin is remarkably reduced. Therefore, in order to exert a predetermined effect by the crosslinking reaction,
It is preferable to contain a polar group capable of forming a certain amount or more of a crosslink bond and reduce the polar group in the low molecular weight component.

The binder resin used in the present invention has two peaks in a GPC chromatogram and a minimum value between the two peaks in the chromatogram of GPC, as exemplified below in order to achieve the object of the present invention. It is necessary that the polymer component forming the peak on the high molecular weight side has a polar group capable of forming a cross-linkage, with the base point as the base point.

The two peaks in the GPC chromatogram of the polymer according to the present invention refer to large peaks in the GPC chromatogram, and the peaks on the low molecular weight side based on the minimum value between the two peaks. The portion refers to a range of lower molecular weight from the location of the minimum value, and the polymer-side peak portion with the minimum value between the both peaks as a starting point is a range of higher molecular weight from the location of the minimum value. Say

The polymer component constituting the peak on the low molecular side in the GPC chromatogram of the binder resin used in the developer according to the present invention is 2,000 to 30,000, more preferably 3,000 to 25. It has a maximum value in the region of 1,000, the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is 3 or less, and the polymer component constituting the peak on the polymer side is 30 10,000 to 3 million, more preferably 400,000 to 2,500,000, and even more preferably 50.
It is preferable that it has a maximum value in the range of 10,000 to 2,000,000 and Mw / Mn is 4 or less.

Further, Mw / M of the binder resin according to the present invention
It is preferable that n is 20 or more. Mw / Mn <20
Then, it is not possible to obtain sufficient fixability and offset resistance.

Further, the polymer-side component constituting the binder resin contains a reactive polar group in an acid value range of more than 1.0. More preferably, it is 5.0 or more. Acid value ≦ 1.
When it is 0, a sufficient crosslinked structure cannot be constructed,
This causes various problems due to deterioration of offset resistance and deterioration of dispersibility of each component inside the developer. The low molecular weight component preferably has an acid value of 3.0 or less, more preferably 1.0 or less and has substantially no acid value.

The glass transition temperature of the binder resin is 55 to 70 ° C., preferably 60 to 65, from the viewpoint of the storability of the developer.
When the glass transition temperature is lower than 55 ° C., deterioration due to blocking of the developer in a high temperature atmosphere and hot offset in a high temperature range occur. On the other hand, if the temperature exceeds 70 ° C., the fixability is adversely affected.

Further, the blending ratio of the high molecular weight component and the low molecular weight component also has a great influence on the fixing property of the developer, and when the proportion of the high molecular weight component in the whole binder resin is lower than 15%, it is in the high temperature range. If hot offset occurs and exceeds 45%, the fixability in the low temperature range deteriorates. Therefore, in the present invention, the proportion of the high molecular weight component in the entire binder resin is desirably 15 to 45%, and preferably,
It is regulated within the range of 20-40%.

In the present invention, the molecular weight of the peak of the chromatogram by GPC (gel permeation chromatography) is measured under the following conditions.

That is, the column was stabilized in a heat chamber at 40 ° C., and THF (tetrahydrofuran) as a solvent was passed through the column at this temperature at a flow rate of 1 ml / min to obtain a sample concentration of 0.05 to 0.6% by weight. 50-200 μl of a THF sample solution of the resin adjusted to 1 is injected and measured. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value and the count number of a calibration curve prepared using several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical C
o. Made or manufactured by Toyo Soda Kogyo Co., Ltd. has a molecular weight of 6 × 1
0 ² , 2.1 × 10 ³ , 4 × 10 ³ , 1.75 × 1
0 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10
^It is suitable to use ⁵ , 8.6 × 10 ⁵ , 2 × 10 ⁶ , and 4.48 × 10 ⁶ standard polystyrene samples at least about 10 points. An RI (refractive index) detector is used as the detector.

The column is 10 ³ to 4 × 10.
^In order to accurately measure the molecular weight region of ⁶ , it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, μ-styragel 500,1 manufactured by Waters.
A combination of 0 ³ , 10 ⁴ and 10 ⁵ and shodex KF-80M and KF-802, 803 manufactured by Showa Denko KK
Combination of 804 and 805 or T made by Toyo Soda
SKgel G1000H, G2000H, G2500
H, G3000H, G4000H, G5000H, G6
A combination of 000H, G7000H and GMH is preferable.

The weight ratio of the low molecular weight component and the high molecular weight component of the binder resin according to the present invention is the area of the low molecular weight side peak portion and the high molecular weight side peak portion based on the minimum value between the peaks of the GPC chromatogram. Calculate from the ratio.

The polymer component having a polar group capable of forming a crosslinkage of the present invention generally has a carboxyl group, a carbonyl group, an ether group, a thioether group, an amino group, an amide group, a hydroxyl group, etc. Among them, a polymer containing at least one of a carboxyl group, a carboxylate group, and a carboxylic acid anhydride group shows the best reactivity. Examples of the carboxyl group-containing monomer for synthesizing the vinyl polymer include acrylic acid,
Acrylic acid and its α- or β-alkyl derivatives such as methacrylic acid, α-ethylacrylic acid and crotonic acid,
There are unsaturated dicarboxylic acids such as fumaric acid, maleic acid, and citraconic acid, and their monoester derivatives or maleic anhydride. These monomers may be used alone or in a mixture, and a desired monomer may be obtained by copolymerization with another monomer. Polymers can be made. Among these, it is particularly preferable to use a monoester derivative of unsaturated dicarboxylic acid.

Examples of the monomer containing a carboxyl group which can be used in the present invention include monomethyl maleate, monoethyl maleate, monobutyl maleate, monooctyl maleate, monoallyl maleate,
Monoesters of α, β-unsaturated dicarboxylic acids such as monophenyl maleate, monomethyl fumarate, monoethyl fumarate, monobutyl fumarate, monophenyl fumarate, etc .; monobutyl n-butenyl succinate, monomethyl n-octenyl succinate, Monoesters of alkenyl dicarboxylic acids such as monoethyl n-butenylmalonate, monomethyl n-dodecenyl glutarate, monobutyl n-butenyl adipate; phthalic acid monomethyl ester, phthalic acid monoethyl ester, phthalic acid monobutyl ester, etc. Aromatic dicarboxylic acid monoesters;

The above-mentioned carboxyl group-containing monomer may be added in an amount of 1 to 30% by weight, preferably 3 to 20% by weight, based on all monomers constituting the polymer side of the binder resin.

The reason why the monoester monomer of dicarboxylic acid as described above is selected will be described in detail later, but the suspension polymerization method is preferable as the method for producing the resin. This is because the suspension polymerization is not suitable for use in the form of an acid monomer having a high solubility in an aqueous suspension, and is preferably used in the form of an ester having a low solubility.

Examples of the comonomer for obtaining the polymer side component of the binder resin used for the developing side and the monomer for obtaining the low molecular weight side component of the present invention include the following.

For example, styrene, o-methylstyrene, m
-Methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene,
2,4-dimethylstyrene, pn-butylstyrene,
Styrene and its derivatives such as p-tert-butyl styrene, pn-hexyl styrene, pn-octyl styrene, pn-nonyl styrene, pn-decyl styrene, pn-dodecyl styrene and the like; ethylene. Ethylenically unsaturated monoolefins such as propylene, butylene, isobutylene; Unsaturated polyenes such as butadiene; Vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide and vinyl fluoride; Vinyl acetate, vinyl propionate, Vinyl esters such as vinyl benzoate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, methacrylic acid. Stearyl, meta Phenyl acrylic acid, dimethylaminoethyl methacrylate, alpha-methylene aliphatic monocarboxylic acid esters such as diethylaminoethyl methacrylate;
Methyl acrylate, ethyl acrylate, acrylic acid n-
Butyl, isobutyl acrylate, propyl acrylate,
Acrylic esters such as n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate; vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl carbazole, N
-N- such as vinylindole and N-vinylpyrrolidone
Vinyl compounds; vinyl naphthalene compounds; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile and acrylamide; and vinyl monomers used alone or in combination of two or more.

Among these, a combination of monomers that forms a styrene copolymer or a styrene acrylic copolymer is preferable.

If necessary, a crosslinking monomer may be added to the peak component on the polymer side.

As the crosslinkable monomer, a monomer having two or more polymerizable double bonds is mainly used.

The binder resin used in the present invention must be a polymer cross-linked with a cross-linkable monomer as exemplified below in order to achieve the object of the present invention.

Aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and the like; diacrylate compounds linked by an alkyl chain; for example, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol. Diacrylate,
1,5-Pentanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, and compounds obtained by replacing the acrylates of the above compounds with methacrylates; diacrylate compounds linked by an alkyl chain containing an ether bond. , Such as diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol # 400 diacrylate, polyethylene glycol # 600 diacrylate, dipropylene glycol diacrylate, and the acrylates of the above compounds replaced with methacrylate Diacrylate compounds linked by a chain containing an aromatic group and an ether bond, for example, polyoxyethylene (2) -2,2-bis ( - hydroxyphenyl) propane diacrylate, polyoxyethylene (4) -2,
2-bis (4-hydroxyphenyl) propane diacrylate, and those obtained by replacing the acrylate of the above compounds with methacrylates; further, polyester type diacrylate compounds, for example, trade name MANDA (Nippon Kayaku) . As the polyfunctional crosslinking agent, pentaerythritol acrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, and acrylates of the above compounds into methacrylate. And the like; triallyl cyanurate, triallyl trimellitate; and the like.

These cross-linking agents are based on other monomer components 10
It is preferable to use 0.001 to 1% by weight, preferably 0.03 to 0.01% by weight, based on 0% by weight.

Among these crosslinkable monomers, aromatic divinyl compounds (particularly divinylbenzene), aromatic groups and ether bonds are preferably used for the resin for developers from the viewpoints of fixing property and anti-offset property. Examples include chain-containing diacrylate compounds.

As a method for producing the binder resin according to the present invention, a solution blending method in which a high molecular weight polymer and a low molecular weight polymer are separately synthesized by a solution polymerization method, these are mixed in a solution state, and then the solvent is removed Also, a dry blending method of melt-kneading with an extruder or the like, and a low molecular weight polymer obtained by a solution polymerization method or the like are dissolved in a monomer constituting a high molecular weight polymer, suspension polymerization is performed, and washing with water is performed. Examples thereof include a two-step polymerization method of obtaining a binder resin by drying. However, the dry blending method has problems in uniform dispersion and compatibility, and the two-step polymerization method has many advantages such as uniform dispersibility, but the low molecular weight component is increased to the high molecular weight component or more. In the presence of a low molecular weight component, which is not possible, it is very difficult to synthesize a sufficient high molecular weight component desired in the present invention, and there is a drawback that unnecessary low molecular weight component is by-produced. The solution blending method is most suitable for application to the present invention.

As a method for synthesizing the low molecular weight component of the binder resin according to the present invention, a known method can be used. However, in the bulk polymerization method, a low molecular weight polymer can be obtained by polymerizing at a high temperature to accelerate the termination reaction rate, but there is a problem that the reaction is difficult to control. In that respect, in the solution polymerization method, a low molecular weight polymer can be easily obtained under mild conditions by utilizing the difference in chain transfer of radicals depending on the solvent, and by adjusting the amount of the initiator and the reaction temperature. It is preferable to obtain a low molecular weight product in the resin composition used in the present invention. In particular, the solution polymerization method under pressure is effective in that the amount of the initiator used is minimized and the influence of the initiator residue is suppressed as much as possible.

On the other hand, as a polymerization method which can be used in the present invention as a method for synthesizing the high molecular weight component of the binder resin according to the present invention, an emulsion polymerization method and a suspension polymerization method can be mentioned.

Among them, the emulsion polymerization method is a method in which a monomer (monomer) almost insoluble in water is dispersed as small particles in an aqueous phase with an emulsifier, and polymerization is performed using a water-soluble polymerization initiator. . In this method, it is easy to control the heat of reaction, and the phase in which the polymerization takes place (oil phase consisting of polymer and monomer)
And the aqueous phase are different, the termination reaction rate is low, and as a result, the polymerization rate is high and the polymerization degree is high. Further, in the production of toner, due to the relatively simple polymerization process and the fine particles of the polymerization product,
It is advantageous as a method for producing a binder resin for a toner because it can be easily mixed with a colorant, a charge control agent and other additives.

However, the polymer produced is liable to become impure due to the added emulsifier, and an operation such as salting out is required to take out the polymer, and suspension polymerization is convenient in order to avoid this inconvenience.

In suspension polymerization, 100 parts by weight or less of the monomer (preferably 1 part by weight) is added to 100 parts by weight of the aqueous solvent.
0 to 90 parts by weight) is preferable. As the dispersant that can be used, polyvinyl alcohol, partially saponified polyvinyl alcohol, calcium phosphate, etc. are used, and there is an appropriate amount such as the amount of monomers in the aqueous solvent, but generally 0.05 to 1 per 100 parts by weight of the aqueous solvent. Used in parts by weight. The polymerization temperature is suitably 50 to 95 ° C., but it should be appropriately selected depending on the initiator used and the target polymer.

In the present invention, the initiator used in the synthesis of the high molecular weight polymer may be any one which is insoluble or hardly soluble in water. For example, benzoyl peroxide or tert-butyl. Peroxyhexanoate or the like is used alone or in combination in an amount of 0.05 to 0.5 parts by weight with respect to 100 parts by weight of the monomer.

Particularly, a polyfunctional polymerization initiator having a polyfunctional structure is preferably used.

Specific examples of the polyfunctional polymerization initiator include:
1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,3-bis- (t-butylperoxyisopropyl) benzene, 2,5-dimethyl-
2,5- (t-butylperoxy) hexane, 2,5-
Dimethyl-2,5-di- (t-butylperoxy) hexyne-3, tris- (t-butylperoxy) triazine, 1,1-di-t-butylperoxycyclohexane, 2,2-di-t -Butyl peroxybutane, 4,4
-Di-t-butylperoxyvaleric acid-n-
Butyl ester, di-t-butyl peroxyhexahydroterephthalate, di-t-butyl peroxyazelate, di-t-butyl peroxytrimethyl adipate, 2,2-bis- (4,4-di-t-butyl) Peroxycyclohexyl) propane, 2,2-t-butylperoxyoctane, and various polymer oxides, etc. A polyfunctional polymerization initiator having a functional group having a polymerization initiation function such as two or more peroxide groups in one molecule. , And diallyl peroxy dicarbonate, t-butyl peroxy maleic acid, t-butyl peroxy allyl carbonate and t-butyl peroxy isopropyl fumarate.
It is selected from polyfunctional polymerization initiators having both a functional group having a polymerization initiation function such as a peroxide group and a polymerizable unsaturated group in the molecule.

Of these, preferred are 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, 1,1-di-t-butylperoxycyclohexane and di-t-butyl. Peroxyhexahydroterephthalate, di-t-butylperoxyazelate and 2,2-bis- (4,4-di-t-butylperoxycyclohexyl) propane, and t-butylperoxyallyl carbonate.

These polyfunctional polymerization initiators can be used alone or in combination, but in order to satisfy various performances required as a binder for toner, the polyfunctional polymerization initiator can be halved. It is preferable to use in combination with a polymerization initiator having a decomposition temperature lower than that for obtaining 10 hours.

Specifically, benzoyl peroxide,
1,1-di (t-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-di (t
-Butylperoxy) valerate, dicumyl peroxide, α, α'-bis (t-butylperoxydiisopropyl) benzene, t-butylperoxycumene, di-t
Organic peroxides such as butyl peroxide, azo and diazo compounds such as azobisisobutyronitrile and diazoaminoazobenzene can be used.

These monofunctional polymerization initiators may be added to the monomer at the same time as the polyfunctional polymerization initiator, but in order to keep the initiator efficiency of the polyfunctional polymerization initiator proper. It is preferably added after the polymerization time has passed the half-life indicated by the polyfunctional polymerization initiator under arbitrary polymerization conditions.

In the present invention, the carboxylic acid group and the carboxylic acid ester moiety in the copolymer obtained by the above method are saponified by alkali treatment. That is, it is preferable to react with an alkali cation component to change the carboxylic acid group or the carboxylic acid ester moiety into a polar functional group. Even if the polymer side component of the binder resin contains a carboxyl group that reacts with the metal-containing compound, the efficiency of the cross-linking reaction with the metal-containing compound decreases when the carboxyl group is in an anhydrous state, that is, in a closed ring state. Because it does.

This alkali treatment may be carried out after the binder resin has been produced, by adding it as an aqueous solution into the solvent used during the polymerization and stirring it. Examples of alkalis that can be used in the present invention include Na, K, Ca, Li, Mg and Ba.
Hydroxides of alkali metals and alkaline earth metals such as;
There are hydroxides of transition metals such as Zn, Ag, Pb, and Ni; hydroxides of quaternary ammonium salts such as ammonium salts, alkylammonium salts, and pyridinium salts, and particularly preferable examples include NaOH and KOH. .

In the present invention, the saponification reaction does not have to be carried out over all of the carboxylic acid groups and carboxylic acid ester moieties in the copolymer, and the saponification reaction partially proceeds to give polar functional groups. It should be different.

The amount of alkali used in the saponification reaction is difficult to determine depending on the type of polar group in the binder resin, the dispersion method, the type of constituent monomers, etc. It may be from 02 to 5 times equivalent. When the amount is less than 0.02 times the equivalent, the saponification reaction is not sufficient, the number of polar functional groups generated by the reaction is small, and as a result, the subsequent metal crosslinking reaction becomes insufficient.
On the other hand, when the amount exceeds 5 times the equivalent, the functional group such as the carboxylic acid ester moiety is adversely affected by hydrolysis of the ester, formation of a salt by saponification reaction, and the like.

When the alkali treatment is carried out in an amount of 0.02 to 5 times the acid value, the residual cation ion concentration after the treatment is contained in the range of 5 to 1000 ppm, which is preferable for defining the amount of alkali. Can be used.

As the reactive metal compound used in the present invention, those containing the following metal ions can be used. Suitable monovalent metal ions include Na ⁺ , Li ⁺ , Cs ⁺ , A
g ⁺ , Hg ⁺ , Cu ^+, etc., and the divalent metal ions include Be ²⁺ , Mg ²⁺ , Ca ²⁺ , Hg ²⁺ , Sn ²⁺ , P.
b ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Zn ²⁺ and the like. Further, as trivalent ions, Al ³⁺ , Sc ³⁺ , Fe ³⁺ ,
^Examples include Co ³⁺ , Ni ³⁺ , Cr ³⁺ , r ³⁺ . Among the compounds containing metal ions as described above, the more decomposable compounds give better results. It is presumed that this is because the decomposable one is more likely to bond the metal ion in the compound with the carboxyl group in the polymer more easily by thermal decomposition.

Among the reactive metal compounds, the organometallic compound is excellent in compatibility and dispersibility with the polymer, and the crosslinking due to the reaction with the metal compound proceeds more uniformly in the polymer, so that more excellent results are given. .

Among the above reactive organometallic compounds, those containing an organic compound rich in vaporization and sublimation as a ligand or a counter ion are particularly useful. Among the organic compounds that form a ligand or counterion with a metal ion, those having the above-mentioned properties include, for example, salicylic acid, salicylamide, salicylamine, salicylaldehyde, salicylosalicylic acid, and ditert-butylsalicylic acid. , And the like, and β-diketones such as acetylacetone and propionacetone, and low-molecular carboxylic acid salts such as acetate and propionic acid.

It is also possible that the metal complex has charge controllability of toner particles. As such a metal complex, there is an azo metal complex represented by the following general formula [I].

[0108]

[Chemical 1]

In the formula, M represents a coordination center metal, and the coordination number is 6
Cr, Co, Ni, Mn, Fe, etc. Ar
Is an aryl group, and examples thereof include a phenyl group and a naphthyl group, which may have a substituent. Examples of the substituent in this case include a nitro group, a halogen group, a carboxyl group, an anilide group, an alkyl group having 1 to 18 carbon atoms, and an alkoxy group. X, X ', Y, Y'are -O-, -CO-,-.
NH- and -NR- (R is an alkyl group having 1 to 4 carbon atoms). Kd represents hydrogen, sodium, potassium, ammonium or aliphatic ammonium.

Specific examples of the complex are shown below.

[0111]

[Chemical 2]

[0112]

[0113]

[0114]

[0115]

[0116]

Alternatively, the basic organic acid metal complex represented by the following general formula [II] imparts a negative charging property and can be used in the present invention.

[0118]

[0119]

Specific examples of the complex are shown below.

[0121]

[0122]

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129]

[0130]

These metal complexes can be used alone or in combination of two or more.

The amount of the metal complex added to the toner particles varies depending on the kind of the toner binder, whether or not the carrier is used in combination, the pigment for coloring the toner, and the reactivity of the metal complex with the binder. Including those of 100% by weight of the binder, 0.01 to 20% by weight, preferably 0.1 to 10% by weight.

By reacting the above-mentioned metal complex with the binder during melt-kneading, the metal complex is more decomposed / reactive and more compatible with the binder or dispersible in the binder, as compared with the case where it is added during the synthesis of the binder. There is an advantage that it is excellent and stable charging property is obtained as a toner.

In the present invention, it is possible to give the metal compound as the cross-linking component charge controllability as a toner, but if necessary, a charge control agent may be used separately from this. A conventionally known negative or positive charge control agent is used.

Charge control agents known in the art today include the following.

The following substances control the toner to be negatively charged.

For example, organic metal complexes and chelate compounds are effective, and as mentioned above, there are monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid type metal complexes. Other examples are aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

The following substances control the toner to be positively charged.

For example, modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate, and phosphonium which is an analog thereof. Onium salts such as salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid,
Ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids, acetylacetone metal complexes; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide;
Examples thereof include diorgano tin borate such as dibutyl tin borate, dioctyl tin borate and dicyclohexyl tin borate, and these can be used alone or in combination of two or more kinds. Among these, charge control agents such as nigrosine and quaternary ammonium salts are particularly preferably used.

In the toner of the present invention, the charging stability,
In order to improve developability, fluidity and durability, it is preferable to add silica fine powder.

The fine silica powder used in the present invention is BE.
Specific surface area due to nitrogen adsorption measured by T method is 30 m ² / g
Those in the above range (particularly 50 to 400 m ² / g) give good results. The fine silica powder is used in an amount of 0.01 to 8 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the toner.

Further, the silica fine powder used in the present invention contains a silicone varnish, various modified silicone varnishes, and various other silicone varnishes for the purpose of hydrophobizing and controlling the charging property, if necessary.
It is also preferably treated with a treating agent such as silicone oil, various modified silicone oils, a silane coupling agent, a silane coupling agent having a functional group, other organosilicon compound, or a combination of various treating agents.

As other additives, lubricants such as Teflon, zinc stearate, polyvinylidene fluoride, and polyvinylidene fluoride are preferable. Alternatively, an abrasive such as cerium oxide, silicon carbide, or strontium titanate,
Of these, strontium titanate is preferable. Alternatively, for example, a fluidity-imparting agent such as titanium oxide or aluminum oxide, among which a hydrophobic agent is particularly preferable. Anti-caking agent,
Alternatively, for example, a conductivity imparting agent such as carbon black, zinc oxide, antimony oxide, tin oxide, etc., or white particles and black particles having opposite polarities can be used in a small amount as a developing property improver.

For the purpose of improving releasability at the time of heat roll fixing, wax-like substances such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, carnauba wax, sazol wax and paraffin wax are used in 100% by weight of binder resin. For 0.5 to
It is also one of the preferred embodiments of the present invention to add about 10% by weight to the toner.

When the toner of the present invention is used as a two-component developer, it is used as a mixture with carrier powder.
In this case, the mixing ratio of the toner and the carrier powder is 0.1 to 50% by weight, preferably 0.5 to 1 as the toner concentration.
0% by weight, more preferably 3 to 5% by weight is desirable.

As the carrier that can be used in the present invention, all known carriers can be used. For example, magnetic powder such as iron powder, ferrite powder, nickel powder, glass beads and the like, and the surface thereof is fluorine-based. Examples include those treated with a resin, a vinyl resin, a silicone resin, or the like.

Further, the toner of the present invention can be used as a magnetic toner by further containing a magnetic material. In this case, the magnetic material also serves as a coloring agent. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxides such as magnetite, hematite, and ferrite; metals such as iron, cobalt, and nickel; or aluminum, cobalt, copper, lead, magnesium, and tin of these metals. Zinc, antimony,
Examples thereof include alloys of metals such as beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten and vanadium, and mixtures thereof.

These ferromagnetic materials have an average particle size of 0.1 to 2
The amount of the resin component is 100 μm, preferably about 0.1 to 0.5 μm.
It is preferably about 20 to 200 parts by weight, more preferably 40 to 150 parts by weight, based on 100 parts by weight of the resin component.

When applied with 10 K oersted, the magnetic characteristics are: coercive force 20 to 150 oersted, saturation magnetization 50 to 50.
It is preferably 200 emu / g and a residual magnetization of 2 to 20 emu / g.

The colorant that can be used in the toner of the present invention includes any appropriate pigment or dye. Toner colorants are well known, and examples of pigments include carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, red iron oxide, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient for maintaining the optical density of the fixed image.
0.1 to 20 parts by weight, preferably 2-1 to 0 parts by weight
The addition amount of 0 parts by weight is good. Further, a dye is further used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, methine dyes, etc.
0.1 to 20 parts by weight, preferably 0.
The addition amount of 3 to 3 parts by weight is good.

To prepare the toner for developing an electrostatic image according to the present invention, a binder resin, a metal compound, a pigment or dye as a coloring agent, a magnetic material, a charge control agent, and other additives as necessary are added. After thoroughly mixing with a mixer such as a Henschel mixer or a ball mill, the resin is melted, kneaded and kneaded using a heat kneader such as a heating roll, kneader or extruder to make the metal compounds compatible with each other. The toner according to the present invention can be obtained by dispersing or dissolving a pigment, a dye, and a magnetic substance, cooling and solidifying, and then pulverizing and classifying.

Further, if desired, desired additives may be sufficiently mixed with a mixer such as a Henschel mixer to obtain the toner for developing an electrostatic image according to the present invention.

Next, the heat fixing constitution of the present invention applicable to the fixing method of the present invention will be specifically described.

In the present invention, the heating element has a smaller heat capacity than the conventional heating roll and has a linear heating portion.
The maximum temperature of the heating part is preferably 100 to 300 ° C.

The film located between the heating element and the pressing member is preferably a heat-resistant sheet having a thickness of 1 to 100 μm. These heat-resistant sheets are highly heat-resistant polyester, PET (polyethylene). Terephthalate), PFA (tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer), PTFE (polytetrafluoroethylene), polyimide, polyamide and other polymer sheets, as well as metal sheets such as aluminum and metal sheets and polymer sheets A laminated sheet is used.

A more preferable film structure is that these heat resistant sheets have a release layer and / or a low resistance layer.

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a structural diagram of an example of a fixing device for carrying out the method of the present invention.

Reference numeral 11 denotes a low-heat-capacity linear heating element which is fixedly supported by the apparatus, and has a thickness of 1.0 mm and a width of 10 m as an example.
resistance material 1 on the alumina substrate 12 having a length of m and a length of 240 mm.
3 is applied to have a width of 1.0 mm, and electricity is applied from both ends in the longitudinal direction. Energization is a pulsed waveform with a cycle of 20 msec of DC 100 V and is given by varying the pulse width according to a desired temperature and energy release amount controlled by the temperature measuring element 14. Approximate pulse width is 0.5 mse
c to 5 msec.

The fixing film 15 moves in the direction of the arrow in the drawing by coming into contact with the heating body 11 whose energy and temperature are controlled in this way. As an example of this fixing film, a thickness of 20 μm
Of heat-resistant film such as polyimide, polyetherimide, PES, PFA at least on the image contact side
It is an endless film having a release layer of 10 μm coated with a conductive agent on a fluororesin such as FE or PAF. Generally, the total thickness is 100 μm, more preferably less than 40 μm. The film drive is driven roller 16 and driven roller 1
Driven by 7 and tension, it moves in the direction of the arrow without wrinkling.

Reference numeral 18 denotes a pressure roller having a rubber elastic layer having a good releasability such as silicon rubber, which presses a heating body through the film at a total pressure of 4 to 20 kg and rotates in pressure contact with the film.
The unfixed developer 20 on the transfer material 19 is guided to the fixing portion by the entrance guide 21 and obtains a fixed image by the above heating.

Although the endless belt has been described above, as shown in FIG. 2, a sheet feeding shaft 24 and a winding shaft 27 may be used, and the fixing film may be an end film.

The image forming apparatus is applicable to all fixing devices for forming an image using a developer such as a copying machine, a printer and a facsimile.

In the low heat capacity linear heating element 11, when the temperature detected by the temperature detecting element 14 is T ₁ , the surface temperature T ₂ of the film 15 facing the resistance material 13 is almost equal to T ₁ . The film surface temperature T _{3 at} the portion where the film 15 is peeled off from the developer fixing surface is the temperatures T ₁ and T ₂ described above.
Is almost equal to the temperature.

Next, the contact charging device applicable to the charging step of the present invention will be specifically described.

FIG. 3 is a schematic configuration diagram of a preferred contact charging device of the present invention. Reference numeral 31 is a photosensitive drum that is a member to be charged, and is formed by forming an organic photoconductor (OPC) 31b that is a photosensitive layer on the outer peripheral surface of a drum base 31a made of aluminum, and rotates at a predetermined speed in the arrow direction. To do. Reference numeral 32 denotes a charging roller which is a charging member brought into contact with the photosensitive drum 31 with a predetermined pressure. The metal cored bar 32a is provided with a conductive rubber layer 32b, and the surface layer 32c which is a releasable coating film on the peripheral surface thereof. Was set up. However, if the resistance is too large, the photoconductor drum 31 is not charged, and if the resistance is too small, a large voltage is applied to the photoconductor drum 31, and the drum is damaged and pinholes are generated. Resistance, that is, a volume resistivity of 10 ⁹ to 10 ¹⁴ Ωm is preferable, and the thickness of the release film at this time is preferably within 30 μm. Further, the lower limit of the thickness of the coating is considered to be about 5 μm, as long as there is no peeling or smearing of the coating.

E is a power source for applying a voltage to the charging roller 32, and a predetermined voltage is applied to the core metal 32a of the charging roller 32.
Supply to. Although E indicates a DC voltage in FIG. 3, it may be a DC voltage superimposed with an AC voltage.

FIG. 4 is a schematic structural view of another example of the contact charging member of the present invention. The same members as those of the apparatus shown in FIG.

The contact charging member 32 'is a blade-shaped member which is brought into contact with the photosensitive drum 31 in the forward direction with a predetermined pressure. The blade 32' is made of a conductive rubber on the metal supporting member 32'a to which a voltage is supplied. 32'b is supported, and a surface layer 3 serving as a releasable coating is provided on the contact portion with the photosensitive drum 31.
2'c is provided. There is no problem such as contact between the blade and the photoconductor drum, and the same effect as the contact charger can be obtained.

Further, the mechanical or electrical pressure applied between the charging member and the photosensitive member is an element related to the gist of the present invention, and the contact pressure of the charging member on the photosensitive member is 5 to 500 g / c.
m, the absolute value of the DC voltage applied to the charging member is 200 to
When AC voltage is applied to 900V, peak-peak voltage is 500 to 5000V, frequency is 50 to 3,000Hz.
It is desirable that each is adjusted.

Although the above-mentioned examples of the charging member are roller-shaped and blade-shaped, the present invention is not limited to this, and the present invention can be applied to other shapes.

Further, in the above-mentioned example of the charging member, the charging member is composed of the conductive rubber layer and the releasable coating, but the present invention is not limited to this. In order to prevent leakage, it is advisable to form a high resistance layer, for example, a hydrin rubber layer with small environmental fluctuation.

Nylon-based resin as a releasable coating,
PVDF (polyvinylidene fluoride), PVDC (polyvinylidene chloride), or the like is used. Amorphous silicon, selenium, ZnO or the like can also be used as the photoconductor. In particular, when amorphous silicon is used for the photoconductor, the image softening may be worse if the softening agent of the conductive rubber layer adheres to the photoconductor as compared with the case where other materials are used. The effect due to the film-like coating becomes great.

Further, in the cleaning step according to the present invention, generally, the photosensitive drum after the toner image transfer is cleaned by wiping off the residual toner after transfer and other contaminants by a cleaning member such as a blade or roller of a cleaner. It is surfaced and repeatedly used for image formation.

It is also possible to perform the cleaning step at the same time as the charging step, the developing step, or the transfer step related to the electrophotography.

The present invention is particularly effective for an image forming apparatus in which the surface of the latent image carrier is an organic compound. When the organic compound forms the surface layer, it has good adhesiveness with the binder resin contained in the toner. Especially when the same material is used, chemical bonding occurs at the contact point and the transferability deteriorates. To do so.

Examples of the surface material of the latent image carrier used in the present invention include, but are not limited to, silicone resin, vinylidene chloride, ethylene-vinyl chloride, styrene-acrylonitrile, styrene-methyl methacrylate, styrene, polyethylene terephthalate and polycarbonate. However, other monomers or copolymers or blends between the exemplified resins can also be used.

The present invention is particularly effective for an image forming apparatus in which the latent image carrier has a diameter of 50 mm or less. This is because in the case of a small-diameter drum, even if the linear pressure is the same, the curvature is large, so that the pressure tends to concentrate at the abutting portion.

It is considered that the same phenomenon occurs in the belt photosensitive member, and it is effective for an image forming apparatus having a radius of curvature of 25 mm or less at the transfer portion.

On the other hand, in order to prevent the developer from sticking to the surface of the coat sleeve, it is necessary to precisely control the weight% of the weight loss of the resin coating layer of the coat sleeve upon heating.

The heating weight loss is the weight loss when the sample is gradually heated in a certain atmosphere, and can be measured by, for example, a thermobalance.

In the present invention, the weight loss upon heating is indicated by the weight loss when a sample is heated at a heating rate of 10 ° C./min in a nitrogen stream using PE7700 and TGA7 manufactured by Perkin Elmer.

The developing device used in the present invention will be described below with reference to the accompanying drawings.

FIG. 5 is a sectional view of an example of the developing device of the present invention.

Reference numeral 51 in the drawing denotes a photosensitive drum as an electrostatic latent image bearing member that carries an electrostatic latent image and rotates in the direction of arrow A, both with and without an insulating layer on the surface. Can be used, of course not only drum shape but sheet shape,
A belt shape is also possible. Reference numeral 52 denotes a sleeve as a developer carrying member that carries the toner 55 on its surface and rotates in the direction of arrow B, and the multipolar permanent magnet 53 is fixed inside the sleeve 52 so as not to rotate. A resin coating layer 54 containing conductive fine particles, which will be described later, is formed on the surface of the sleeve 52 in a thickness of about 0.5 μm to 30 μm. Reference numeral 56 denotes a doctor blade as a member that regulates the layer of the toner 55 on the surface of the carried sleeve 52 to a predetermined thickness, so that the gap between the surface of the sleeve 52 and the doctor blade 6 is about 50 μm to 500 μm. It is arranged.

When the developing device constructed as described above is activated and the sleeve 52 rotates in the direction of arrow B, the photosensitive drum 51 is caused by the friction between the toners 55 or the contact between the surface of the sleeve 52 and the toner 55 in the developer accommodating chamber. A charge having a polarity opposite to that of the upper electrostatic latent image is applied to the toner 55 and applied to the surface of the sleeve 52. The toner layer applied to the surface of the sleeve further has a doctor blade 5 disposed so as to face one magnetic pole (S pole in the figure) position of the multi-pole permanent magnet 53.
6 is a uniform and thin layer (layer thickness is about 30 μm to 300 μm
m) and is conveyed to the developing area formed by the photosensitive drum 51 and the sleeve 52.

Further, in the developing area, by applying an AC bias between the sleeve 52 and the surface of the photosensitive drum 51, the toner 55 on the sleeve 52 may fly toward the photosensitive drum.

Here, the resin coating layer 54 formed on the surface of the sleeve will be described.

As the resin layer, a film-forming polymer material containing conductive fine particles is used, and the weight loss upon heating up to 300 ° C. is 2% by weight or less of the entire resin layer, and further sufficient performance is obtained. In order to take it out, it is preferable to make it 1% by weight or less. The weight loss of the resin layer due to heating is due to residual monomers, low-molecular weight oligomers, reaction catalyst residues, and as required, which are generated during the coating treatment of the film-forming polymer material described below or during the coating treatment during the production of the coat sleeve. This is because volatile components such as an organic solvent escape from the resin layer by heating. As a result of studies by the present inventors, when the content of these volatile components in the resin layer exceeds 2% by weight, not only the adhesion of the developer to the developer carrying member is promoted but also the charging property is improved. It became clear that it also inhibits.

The conductive fine particles added to the resin layer are preferably carbon fine particles, or carbon fine particles and crystalline graphite, or crystalline graphite.

The crystalline graphite used in the present invention is roughly classified into natural graphite and artificial graphite. Artificial graphite is made by solidifying pitch coke with tar pitch or the like, firing it once at about 1200 ° C, and then putting it in a graphitization furnace.
By treating at a high temperature of about 300 ° C., carbon crystals grow and change into graphite. Natural graphite is completely graphitized from the ground by natural geothermal heat and underground high pressure for a long time. These graphites have a wide range of industrial uses because they have various excellent properties. Graphite is a very soft and slippery crystalline mineral with dark gray or black luster. It is used for pencils and has heat resistance and chemical stability, so it is used as a lubricant, fire resistance, powder for electrical materials, etc. It is used in the form of solids and paints. The crystal structure is hexagonal and others belong to the rhombohedral system,
It has a completely layered structure. Regarding electrical characteristics,
Free electrons exist between the carbon-carbon bonds and are good conductors of electricity. The graphite used in the present invention may be natural or artificial.

Further, the graphite used in the present invention preferably has a particle size of 0.5 μm to 10 μm.

The film-forming polymer material is, for example, styrene resin, vinyl resin, polyether sulfone resin, polycarbonate resin, polyphenylene oxide resin,
Thermosetting of thermoplastic resins such as polyamide resin, fluororesin, fibrous resin, acrylic resin, epoxy resin, polyester resin, alkyd resin, phenol resin, melamine resin, polyurethane resin, urea resin, silicone resin, polyimide resin, etc. Resin or photocurable resin can be used. Among them, those having releasability such as silicone resin and fluororesin, or those having excellent mechanical properties such as polyether sulfone, polycarbonate, polyphenylene oxide, polyamide, phenol, polyester, polyurethane and styrene resin are more preferable. .

The electrically conductive amorphous carbon is generally defined as "an aggregate of crystallites formed by burning or pyrolyzing a hydrocarbon or a compound containing carbon in a state where the air supply is insufficient". . In particular, it is widely used because it has excellent electric conductivity, and it can be filled with a polymer material to give conductivity, or it can obtain an arbitrary conductivity to some extent by controlling the amount added. The particle size of the conductive amorphous carbon used in the present invention is preferably 10 μm to 80 μm, more preferably 15 μm to 40 μm.

In the sleeve of the present invention, for example, a surface of a raw tube (surface roughness 2S) after drawing of aluminum is sprayed with a prepared solution as in the following formulation example to a thickness of about 0.1.
The coating treatment can be performed in a step of coating about 5 to 30 μm and then heat curing in a drying furnace. The method of reducing the volatile components in the resin layer is achieved by adjusting the heating temperature and the heating time during the heat treatment such as the above-mentioned thermosetting step.

Formulation Example 1 Resin: 40 parts by weight of phenolic resin Carbon: 5 parts by weight of amorphous carbon (CONDUCTEX975UB manufactured by Colombian Carbon Co.) Conductive lubricant: 25 parts by weight of graphite (particle diameter: 2 μm) Diluent: Methyl alcohol / methyl Cellosolve 200 parts by weight

Formulation Example 2 Resin: Phenol resin 20 parts by weight Conductive lubricant: Graphite (particle size: 3 μm) 20 parts by weight Diluent: Methyl alcohol / methyl cellosolve 225 parts by weight

Formulation Example 3 Resin: Phenol resin 30 parts by weight Conductive lubricant: Graphite (particle size: 1 μm) 15 parts by weight Diluent: Methyl alcohol / methyl cellosolve 225 parts by weight

Through the steps of the above prescription examples 1 to 3,
Table 1 below shows the ratio of the weight loss of the resin layer of the prepared resin-coated sleeve up to 300 ° C. to the total weight and the thermosetting conditions.

[0200]

[Table 1]

Next, the transfer device of the present invention will be described in detail.

The contact pressure of the transfer device of the present invention is 3 g /
Set to cm or higher.

The linear pressure is calculated by the following formula.

(Linear pressure) [g / cm] = (total pressure applied to transfer member) [g] / (contact length) [cm] Transfer when contact pressure is less than 3 g / cm Transport of parts,
Transfer failure due to insufficient transfer current occurs, which is not preferable.

The transfer device used in the present invention may be a transfer roller as shown in FIG. 6 or a transfer belt as shown in FIG.

FIG. 6 is a schematic side view of the essential part of a typical image forming apparatus of this type. The apparatus shown in the drawing is a cylindrical image carrier that extends in the direction perpendicular to the plane of the drawing and rotates in the direction of arrow A. A body (hereinafter referred to as a photoconductor) 61 and a conductive transfer roller 62 that abuts on the body 61 are provided.

Around the photosensitive member 61, a primary charging device for uniformly charging the surface of the photosensitive member 61, and an optical image such as image-modulated laser light on the charging surface and reflected light from the original are projected. , An exposure unit that attenuates the potential of the relevant portion to form an electrostatic latent image, a developing unit, a cleaner that removes residual toner remaining on the surface of the photoconductor after transfer, and other members necessary for image formation. Needless to say, they are all omitted.

The transfer roller 62 is composed of a cored bar 62a and a conductive elastic layer 62b, and the conductive elastic layer 62b has a volume resistance of 10 ⁶ to 10 ¹⁰ Ω · cm such as urethane and EPDM in which a conductive material such as carbon is dispersed. It is made of elastic material. A bias is applied to the cored bar 62a by a constant voltage power source 68.

FIG. 7 shows a transfer belt to which the present invention is applied. The transfer belt 69 is supported and driven by the conductive roller 70. Pressurization of the transfer device is usually performed by pressurizing the end bearing of the cored bar 62a or 70.

The present invention is particularly effective for an image forming apparatus in which the surface of the latent image carrier is an organic compound. When the organic compound forms the surface layer, it has good adhesiveness with the binder resin contained in the toner. Especially when the same material is used, chemical bonding occurs at the contact point and the transferability deteriorates. To do so.

Examples of the surface material of the latent image carrier used in the present invention include, but are not limited to, silicone resin, vinylidene chloride, ethylene-vinyl chloride, styrene-acrylonitrile, styrene-methyl methacrylate, styrene, polyethylene terephthalate and polycarbonate. However, other monomers or copolymers or blends between the exemplified resins can also be used.

In the present invention, the latent image carrier 61 has a diameter of 50 mm.
It is particularly effective for the following image forming apparatuses. This is because in the case of a small-diameter drum, even if the linear pressure is the same, the curvature is large, so that the pressure tends to concentrate at the contact portion.

It is considered that the same phenomenon occurs in the belt photosensitive member, and it is effective for an image forming apparatus having a curvature of 25 mm or less at the transfer portion.

[0214]

EXAMPLES The present invention will be described below with reference to specific examples, but the present invention is not limited thereto.
Parts mean parts by weight.

(Synthesis Example 1 of resin) 200 parts of xylene was placed in a reaction vessel and heated to a reflux temperature, and styrene 94 was added thereto.
Parts, butyl acrylate 6 parts, and di-tert-butyl peroxide 8.5 parts were mixed, and solution polymerization was completed under reflux of xylene for 6 hours to obtain a low molecular weight resin solution.

On the other hand, 70 parts of styrene, 25 parts of butyl acrylate, 5 parts of monobutyl maleate, 0.003 parts of divinylbenzene, 0.2 parts of polyvinyl alcohol, 200 parts of degassed water, 2,2-bis (4,4) 0.22 parts of -di-tert-butylperoxycyclohexyl) propane was mixed, suspended and dispersed. The suspension-dispersed solution was heated and kept at 85 ° C. for 24 hours in a nitrogen atmosphere to complete the polymerization, thus obtaining a high molecular weight resin. Next, the resin was washed for 2 hours with an aqueous solution of NaOH having twice the acid value of the resin.

30 parts of this high-molecular-weight resin is put into the solution of 70 parts of the above-mentioned low-molecular-weight resin at the end of the solution polymerization, and the mixture is dissolved and mixed in a solvent, and then the solvent is distilled off to give a styrene-based copolymer. A polymer composition was obtained.

(Resin Synthesis Example 2) A styrene-based copolymer composition was prepared in the same manner as in Synthesis Example 1 except that the mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 1 was changed to 80 parts and 20 parts, respectively. Got

(Resin Synthesis Example 3) A styrene-based copolymer composition was prepared in the same manner as in Synthesis Example 1 except that the mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 1 was changed to 60 parts and 40 parts, respectively. Got

(Resin Synthesis Examples 4 to 7) The monomer species, the mixing ratio, the initiator, the reaction conditions, etc. were changed in accordance with the above Synthesis Example 1,
The styrene-based copolymer compositions of Synthesis Examples 4 to 7 were obtained.

Table 2 shows the monomer composition, resin physical properties and the like of Synthesis Examples 1 to 7 collectively.

[0222]

[Table 2]

(Comparative Synthesis Examples 1 to 4) In the same manner, resins of Comparative Synthesis Examples 1 to 4 were synthesized with the monomer compositions shown in Table 3.

[0224]

[Table 3]

[0225] Example 1 Resin Synthesis Example 1 of the copolymer 100 parts Magnetic material fine powder 100 parts negatively chargeable monoazo pigment 0.6 parts low molecular weight polypropylene 4 parts

The above mixture was melt-kneaded with a twin-screw extruder heated to 110 ° C., the cooled kneaded product was coarsely pulverized with a hammer mill, and further finely pulverized with a jet mill to obtain a fine powder, which was classified by wind. The magnetic powder-containing resin particles having a weight average particle diameter of 6.8 μm.

1.2 parts of silica fine powder was mixed with 100 parts of the resin particles to obtain a magnetic developer.

Next, the apparatus used in this example will be described. In this embodiment, a commercially available laser beam printer L is used.
The charging and fixing device of BP-8II (manufactured by Canon Inc.) was modified into the following configuration and the operation was performed under the following conditions.

The charging device used in the contact charging device shown in FIG. 3 has a contact pressure of 50 g / cm on the photosensitive member, a voltage of -600 V, AC of 1200 Vpp and a frequency of 1 applied to the charging member.
It was set to 800 Hz.

The fixing sheet used in the heat fixing device of the present invention shown in FIG. 1 has a surface temperature of the temperature measuring element 14 of the heating element 11 of 150 ° C., a total pressure between the heating element 11 and the pressure roller 18 of 6 kg, and a pressure of The nip between the roller and the film is 3 mm, and the rotation speed of the pressure roller 18 is 24 mm / sec (LBP
-LX equivalent).

As the heat-resistant sheet, a polyimide film having a thickness of 50 μm having a low-resistance release layer in which a conductive material was dispersed in PTFE was used on the contact surface with the transfer material.

Under the above setting conditions, 4 sheets (A4) / min
The print test for forming a developer image by the reversal development method at a printing speed of 3,000 consecutive sheets was carried out at room temperature and normal humidity (2
The image obtained was evaluated at 5 ° C. and 60% RH), and the following items were evaluated. At the same time, the appearance of the surface of the fixing film was observed to evaluate its durability.

[0233] Examples 2-7 below, but using the resin of Synthesis Example 2-7 were prepared and print test of the developer in the same manner as in Example 1.

The results are shown in Table 4.

Comparative Examples 1 to 4 Preparation of a developer and a print test were conducted in the same manner as in Example 1 except that the resins of Comparative Synthesis Examples 1 to 4 were used, and the same items were evaluated.

The results are shown in Table 4.

The image density is "Macbeth reflection densitometer".
(Manufactured by Macbeth Co., Ltd.), the relative image density of the printed image was measured with the white background portion of the document set to 0.0.

[0238]

[Table 4]

[A] Evaluation of print-out image (1) Fixability The fixability is determined by applying a load of 50 g / cm ² and rubbing the fixed image with a soft thin paper to reduce the image density before and after rubbing. It was evaluated by (%).

◎ (excellent): 0 to 5%, ◯ (good): 5 to 10% △ (possible): 10 to 20%, × (impossible): 20% or more

(2) Anti-Offset Property The anti-offset property was evaluated by printing out a sample image having an image area ratio of about 5% and measuring the degree of stain on the image after 3000 sheets.

◎: Very good (not generated), ○: Good (almost no occurrence) △: Practical, ×: Practical

(3) Image Density 3000 ordinary plain papers (75 g / m ² ) for copying machines were evaluated by maintaining the image density at the end of printing out.

◎ (excellent): 1.40 or more, ○
(Good): 1.40 to 1.35 Δ (Fair): 1.35 to 1.00, × (Failure): 1.0
0 or less

(4) Image quality The scattering of the developer, rubbing and the like were visually evaluated.

◎: Very good, ○: Good △: Practical, ×: Practical

[B] Evaluation of Durability of Fixing Film (1) Surface Property The appearance of scratches and scrapes on the surface of the fixing film after the printout test was visually evaluated.

◎: Very good (not generated), ○: Good (almost no occurrence) △: Practical, ×: Practical

(2) Fixing State of Residual Developer The fixing state of residual developer on the surface of the fixing film after the printout test was visually evaluated.

⊚: Very good (not generated), ◯: Good (almost no occurrence) Δ: Practical, X: Practical

[C] Evaluation of Durability of Charging Roller (1) Fixing Status of Residual Developer The sticking status of residual developer on the surface of the charging roller after the printout test was visually evaluated.

⊚: Very good (not generated), ◯: Good (almost no occurrence) Δ: Practical, ×: Practical (resin synthesis example 8)

200 parts of xylene was placed in the reaction vessel and the temperature was raised to the reflux temperature. 85 parts of styrene and 15 parts of butyl acrylate were mixed with 8 parts of di-tert-butyl peroxide, and solution polymerization was completed under reflux of xylene for 6 hours to obtain a low molecular weight resin solution.

On the other hand, 70 parts of styrene, 25 parts of butyl acrylate, 5 parts of monobutyl maleate, 0.003 parts of divinylbenzene, 0.2 parts of polyvinyl alcohol, 200 parts of degassed water, 1,1-di-t-butyl. Peroxy-3,
0.1 part of 3,5-trimethylcyclohexane was mixed, suspended and dispersed. The suspension-dispersed solution was heated and kept at 85 ° C. for 24 hours in a nitrogen atmosphere to complete the polymerization, thus obtaining a high molecular weight resin. Next, N equivalent to twice the acid value of this resin
It was washed with an aqueous aOH solution for 2 hours.

30 parts of this high-molecular-weight resin was added to the solution of 70 parts of the above-mentioned low-molecular-weight resin at the end of the solution polymerization, and the mixture was completely dissolved in the solvent and mixed, and then the solvent was distilled off to give styrene. A system copolymer composition was obtained.

(Synthesis Example 9) A styrene-based copolymer composition was prepared in the same manner as in Synthesis Example 8 except that the mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 8 was changed to 80 parts and 20 parts, respectively. Got

(Resin Synthesis Example 10) The mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 8 was 60 parts and 40 parts, respectively.
A styrene-based copolymer composition was obtained in the same manner as in Synthesis Example 8 except that parts were added.

(Resin Synthesis Example 11 and Comparative Synthesis Examples 5 to 7)
The monomer species, the mixing ratio, the initiator, the reaction conditions, etc. were changed in accordance with Synthesis Example 8 above, and Synthesis Example 11 and Comparative Synthesis Examples 5 to 7 were performed.
A styrene-based copolymer composition of was obtained.

These are summarized in Table 5.

[0260]

[Table 5]

[0261] Example 8 Copolymer 1 part to 100 parts magnetic fine powder 100 parts negatively chargeable monoazo pigment of Resin Synthesis Example 8 Low molecular weight polypropylene 4 parts

The above mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C., the cooled kneaded product was coarsely crushed with a hammer mill, and further finely crushed with a jet mill to obtain a fine powder, which was classified by wind. The magnetic powder-containing resin particles having a weight average particle diameter of 6.7 μm.

A magnetic developer was obtained by mixing 1.2 parts of silica fine powder with 100 parts of the resin particles.

Next, using this developer, a fixing device of a commercially available laser beam printer LBP-8II (manufactured by Canon Inc.) was used, and the heating fixing device shown in FIG. 1 (the surface temperature of the temperature detecting element 14 of the heating element 11 was 150 ° C., The total pressure between the heating body 11 and the pressure roller 18 is set to 6 kg, and the nip between the pressure roller and the film is set to 3 mm), and the developer carrying body is prescribed in Formulation Example 1.
A printout test in which an image was formed by the reversal development method was continuously performed 4000 times at a printing speed of 4 sheets (A4) / min. At the same time, the state of the surface of the developer carrying member was observed to evaluate its durability.

The results are summarized in Table 6.

[0266] In the same manner as in Example 8 except using the resin of Example 9 Synthesis Example 9 A developer was prepared and subjected to the same printout test.

The results are summarized in Table 6.

[0268] In the same manner as in Example 8 except using the resin of Example 10 Synthesis Example 10 A developer was prepared and subjected to the same printout test.

The results are summarized in Table 6.

[0270] Example 11 2 parts of the copolymer 100 parts Magnetic material fine powder 100 parts negatively chargeable dialkyl salicylic acid chromium complex of Resin Synthesis Example 11 Low molecular weight polypropylene 4 parts

A developer was prepared from the above mixture in the same manner as in Example 8.

Then, using this developer, a printout test was conducted in the same manner as in Example 8 except that the developer carrying member was prepared as in Formulation Example 2.

The results are summarized in Table 6.

Comparative Example 5 The same printout test as in Example 10 was carried out except that the developer carrier was changed to that of Formulation Example 3.

The results are summarized in Table 6.

Comparative Example 6 A developer was prepared in the same manner as in Example 8 except that the resin of Comparative Synthesis Example 5 was used, and the same printout test as in Comparative Example 5 was conducted.

The results are summarized in Table 6.

Comparative Example 7 A developer was prepared in the same manner as in Example 8 except that the resin of Comparative Synthesis Example 6 was used, and the same printout test as in Comparative Example 5 was conducted.

The results are summarized in Table 6.

Comparative Example 8 A developer was prepared in the same manner as in Example 8 except that the resin of Comparative Synthesis Example 7 was used, and the same printout test as in Comparative Example 5 was conducted.

The results are summarized in Table 6.

[0282]

[Table 6]

[A] Evaluation of Printout Image Evaluation was made in the same manner as in Table 4.

[B] Evaluation of Durability of Surface of Developer-Supporting Member After the printout test, the state of sticking of the residual developer on the surface of the developer-supporting member was visually evaluated.

⊚: Very good (not generated), ◯: Good (almost no occurrence) Δ: Practical, X: Practical (resin synthesis example 12)

200 parts of xylene was placed in the reaction vessel and the temperature was raised to the reflux temperature. Add 100 parts of styrene to this.
Eight parts of t-butyl peroxide were mixed, and solution polymerization was completed under reflux of xylene for 6 hours to obtain a low molecular weight resin solution.

On the other hand, 67 parts of styrene, 28 parts of butyl acrylate, 5 parts of monobutyl maleate, 0.005 parts of divinylbenzene, 0.2 parts of polyvinyl alcohol, 200 parts of degassed water, 1,1-di-t-butyl. 0.1 part of peroxycyclohexane was mixed, suspended and dispersed. The suspension-dispersed solution was heated and kept at 85 ° C. for 24 hours in a nitrogen atmosphere to complete the polymerization, thus obtaining a high molecular weight resin. Next, the resin was washed for 2 hours with an aqueous solution of NaOH having twice the acid value of the resin.

30 parts of this high molecular weight resin was added to the solution at the end of the solution polymerization of 70 parts of the above-mentioned low molecular weight resin, completely dissolved in the solvent and mixed, and then the solvent was distilled off to give styrene. A system copolymer composition was obtained.

(Synthesis Example 13 of Resin) The mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 12 was 80 parts and 2 respectively.
A styrene-based copolymer composition was obtained in the same manner as in Synthesis Example 12 except that 0 part was used.

(Resin Synthesis Example 14) The mixing ratio of the high molecular weight resin and the low molecular weight resin of Synthesis Example 12 was 60 parts and 4 parts, respectively.
A styrene-based copolymer composition was obtained in the same manner as in Synthesis Example 12 except that 0 part was used.

(Resin Synthesis Examples 15 to 18 and Comparative Synthesis Example 8)
-11) Hereinafter, the monomer species, the mixing ratio, the initiator, the reaction conditions and the like are changed according to Synthesis Example 12, and Synthesis Examples 15 to 18,
Further, styrene-based copolymer compositions of Comparative Synthesis Examples 8 to 11 were obtained.

These are summarized in Table 7.

[0293]

[Table 7]

[0294] Example 12 0.6 parts of the copolymer 100 parts Magnetic material fine powder 100 parts negatively chargeable monoazo pigment of Resin Synthesis Example 12 Low molecular weight polypropylene 4 parts

The above mixture was melt-kneaded with a twin-screw extruder heated to 130 ° C., the cooled kneaded product was coarsely pulverized with a hammer mill, and further finely pulverized with a jet mill. The magnetic powder-containing resin particles having a weight average particle diameter of 6.5 μm.

1.2 parts of silica fine powder was mixed with 100 parts of the resin particles to obtain a magnetic developer.

Next, the apparatus used in this example will be described. In this example, the transfer device and the fixing device of a commercially available laser beam printer LBP-8II (manufactured by Canon Inc.) were modified into the following configurations.

A transfer device as shown in FIG. 6 is incorporated, and the condition of the transfer roller is that the surface rubber hardness of the transfer roller is 27.
The transfer current was 1 μA and the contact pressure was 30 g / cm.

An electrostatic latent image is formed by setting the primary charging to -570 V, and a gap (300 μm) is set in a non-contact manner between the photosensitive drum and the developer layer on the developer carrying member (including the magnet), and an AC bias (f = 1800 Hz Vpp = 1200 V) and DC bias (VDC = -380 V) were applied to the developing drum.

Next, in the heat fixing device of the present invention shown in FIG. 1, the surface temperature of the temperature detecting element 14 of the heating body 11 is 150.
C., the total pressure between the heating element 11 and the pressure roller 18 is 6 kg,
The nip between the pressure roller and the film is 3 mm, and the rotation speed of the pressure roller 18 is 24 mm / sec (LBP-A40
4 equivalent).

As the heat-resistant sheet, a 60 μm-thick polyimide film having a low-resistance release layer in which a conductive substance was dispersed in PTFE was used on the contact surface with the transfer material.

Under the above setting conditions, 4 sheets (A4) / min
At a normal temperature and normal humidity (2
The image obtained was evaluated at 5 ° C. and 60% RH), and the following items were evaluated. At the same time, the states of the surface of the fixing film and the photoconductor were observed to evaluate their durability.

[0303] Examples 13 to 18 below, except that a resin of Synthesis Example 13 to 18 was conducted to prepare and print test of the developer in the same manner as in Example 12. The results are shown in Table 8.

Comparative Examples 9-12 Example 12 except that the resins of Comparative Synthesis Examples 8-11 are used.
Preparation of developer and print test were carried out in the same manner as above, and the same items were evaluated. The results are shown in Table 8.

[0305]

[Table 8]

[A] Evaluation of Printout Image Evaluation was made in the same manner as in Table 4. The image quality was evaluated by visually observing not only the scattering of the developer and the roughness but also the hollow portion of the image.

[B] Evaluation of Surface State of Photoreceptor (1) Surface Property Occurrence of scratches and scrapes on the surface of the photoreceptor after the printout test was visually evaluated.

⊚: Very good (no occurrence), ◯: Good (almost no occurrence) Δ: Practical, X: Practical

(2) Toner Fixing State The residual developer fixing state after the printout test was visually evaluated.

⊚: Very good (no occurrence), ◯: Good (almost no occurrence) Δ: Practical, X: Practical

[C] Surface condition of fixing film Evaluation was made in the same manner as in Table 4.

[0312]

As described above, according to the present invention, the reactive polar group is contained only in the polymer side component constituting the binder resin in the developer, and the reactive polar group is cross-linked with the metal-containing compound so that the inside of the developer is protected. By improving the dispersibility of each component, it is possible to improve the fixing of the developer to the surface of the developer carrier or the contact charging member while realizing the heat fixing by the low heat capacity, and to prevent the charging failure of the developer. In addition, it is possible to prevent a void in transfer and always form a good image.

[Brief description of drawings]

FIG. 1 is a structural diagram showing an example of a fixing device for carrying out the method of the present invention.

FIG. 2 is a structural diagram showing another example of a fixing device for carrying out the method of the present invention.

FIG. 3 is an explanatory view schematically showing a charging roller for carrying out the method of the present invention.

FIG. 4 is an explanatory view showing the outline of a charging blade for carrying out the method of the present invention.

FIG. 5 is a schematic view of a developing device for carrying out the image forming method of the present invention.

FIG. 6 is an explanatory view showing an example of a transfer device for carrying out the method of the present invention.

FIG. 7 is an explanatory view showing another example of the transfer device for carrying out the method of the present invention.

[Explanation of symbols]

 11 Low Heat Capacity Linear Heater 12 Alumina Substrate 13 Resistance Material 14 Thermometric Element 15 Fixing Film 16 Drive Roller 17 Driven Roller 18 Pressure Roller 19 Transfer Material 20 Unfixed Developer 21 Inlet Guide 24 Sheet Delivery Axis 27 Winding Axis 31 Static Electrostatic image bearing member (photosensitive drum) 32, 32 'Charging member 51 Electrostatic latent image bearing member (photosensitive drum) 52 Developer bearing member (sleeve) 53 Multi-pole permanent magnet 54 Resin coating layer 56 Doctor blade 61 Electrostatic latent Image carrier (photosensitive drum) 62 Contact transfer rollers 64, 67 Transfer material conveying guide 68 Transfer bias power supply 69 Contact transfer belt 70 Conductive roller E Power supply

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location G03G 15/20 101 G03G 9/08 365 (72) Inventor Masayoshi Kato 3-chome Shimomaruko, Ota-ku, Tokyo 30 No. 2 Canon Inc.

Claims (8)

[Claims] 1. A process of bringing a charging member into contact with a member to be charged from the outside and applying a voltage from the outside to perform charging, a cleaning process of removing the developer from the member to be charged, and a visible image of the developer. A developer used in an image forming method having a fixing step of heating and fixing to a recording material, which contains at least a binder resin, a colorant and a metal-containing compound, and is measured by GPC of the binder resin. The chromatogram has at least one local maximum in the respective regions of molecular weights of 2,000 to 30,000 and 300,000 to 3,000,000, and at least the polymer constituting the local maximum has a cross-linking bond. A heat fixing developer having a polar group capable of forming. 2. A developer comprising: the charging step, the cleaning step; and a heating member fixed and supported, and a pressure member that is in pressure contact with the heating member and is in close contact with the heating member via a film. The heat-fixing developer according to claim 1, which is used in an image forming method having a fixing step of heat-fixing the visible image of 1. to a recording material. 3. A step of bringing a charging member into contact with an object to be charged from the outside and applying a voltage from the outside to perform charging, a cleaning step of removing a developer from the object to be charged, and a fixedly supported heating. A body and a pressure member that is in pressure contact with the heating body and is brought into close contact with the heating body through a film,
An image forming method comprising a fixing step of heating and fixing a visible image of a developer on a recording material, wherein the developer contains at least a binder resin, a colorant and a metal-containing compound. The chromatogram measured by GPC has a molecular weight of 2,000 to 3
The polymer having at least one local maximum in each of the ranges of 10,000 and 300,000 to 300,000, and at least the polymer constituting the local maximum has a polar group capable of forming a cross-linkage. Image forming method. 4. A resin layer containing at least conductive fine particles on its surface, and carrying a developer having a weight loss on heating of the resin layer up to 300 ° C. of not more than 2% by weight of the total weight of the resin layer. A developer applied to an image forming method using a developing device having a developer carrying member for carrying out the development, wherein the developer contains at least a binder resin, a colorant and a metal-containing compound. The chromatogram of the coating resin measured by GPC has a molecular weight of 2,000 to 30,
000 and 300,000 to 3,000,000 each has at least one maximum value, and at least the polymer constituting the maximum value on the polymer side has a polar group capable of forming a cross-linkage. Developer for heat fixing. 5. A developer having a resin layer containing at least conductive fine particles on its surface, and carrying a developer whose weight loss on heating up to 300 ° C. is 2% by weight or less of the total weight of the resin layer. An image forming method using a developing device having a developer carrying member for carrying out the development, wherein the developer contains at least a binder resin, a colorant and a metal-containing compound, and is measured by GPC of the binder resin. The obtained chromatogram has molecular weights of 2,000 to 30,000 and 30.
Image formation characterized by having at least one local maximum in each region of 3 million to 3 million, and at least only a polymer constituting the local maximum has a polar group capable of forming a crosslinkage. Method. 6. In the step of developing the electrostatic charge image on the electrostatic charge image carrier with a developer and electrostatically transferring the electrostatic charge image to a transfer material via a transfer device, the electrostatic charge image carrier and the transfer device have a linear pressure. 3 g
A developer used in an image forming method, which comprises a transfer device in contact with the recording material at a rate of at least 1 cm / cm, and further has a fixing step of heating and fixing a visible image of the developer on a recording material, the developer comprising at least a binder resin, The binder resin contains a colorant and a metal-containing compound, and the chromatogram of the binder resin measured by GPC has at least one local maximum in the respective regions of molecular weights of 2,000 to 30,000 and 300,000 to 3,000,000. A heat-fixing developer having a polar group capable of forming a cross-linkage by a polymer having a value and at least having a maximum value on the high molecular side. 7. The developer development is performed by the transferring step, further by a fixedly supported heating body and a pressing member which is brought into pressure contact with the heating body and is brought into close contact with the heating body through a film. The heat fixing developer according to claim 6, which is used in an image forming method having a fixing step of fixing an image on a recording material by heating. 8. In the step of developing the electrostatic charge image on the electrostatic charge image carrier with a developer and electrostatically transferring the electrostatic charge image to a transfer material via a transfer device, the electrostatic charge image carrier and the transfer device have a linear pressure. 3 g
Transfer step using a transfer device in contact with the heating member at a rate of not less than 1 cm / cm, and further, a heating member that is fixed and supported, and a pressurizing member that is in pressure contact with the heating member and is in close contact with the heating member through a film. An image forming method having a fixing step of heat-fixing a developed image of a developer on a recording material by means of a member, wherein the developer contains at least a binder resin, a colorant and a metal-containing compound. The chromatogram of the resin to be measured by GPC has a molecular weight of 2,000 to 3
It has at least one local maximum in each of the ranges of 30,000 and 300,000 to 3,000,000, and at least the polymer constituting the local maximum has a polar group capable of forming a cross-linkage. Image forming method.