JPH0619204A - Full-color toner and picture forming method - Google Patents

Abstract

PURPOSE:To provide a full-color toner having stabilized color reproducibility, high density and durability and to form a picture by using the yellow toner, magenta toner, cyan toner and black toner having a specified binder resin. CONSTITUTION:The binder resin for the yellow, magenta and cyan toners consists of a polyester resin obtained by polycondensing 45-55mol% diol and 55-45mol% carboxylic acid, and the hydroxyl value of the resin is controlled to <=50, the weight average mol.wt. (Mw) to 6,000-10,000, the number average mol.wt. (Mn) to 1,500-50,000 and Mw/Mn to 4-6. The binder resin for the black toner contains a polyester resin consisting of 25-35mol% aromatic dicarboxylic acid, 2-4mol% aromatic tricarboxylic acid, 12-18mol% dicarboxylic acid and 45-60mol% etherized diphenol, and the hydroxyl value is controlled to 10-20, the Mw to 13,000-20,000, Mn to 5,000-8,000 and Mw/Mn to 2-3.5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry developer for electrophotography, which is a full color toner for a full color copying machine using a non-magnetic toner and a magnetic toner at the same time, an image forming method using the toner, and a black and white. The present invention relates to a full-color toner for a full-color developer, which is suitable for an image having different surface glossiness between a black image and a full-color image in a full-color copying machine, and a method for forming an image using the toner. It is a thing.

[0002]

2. Description of the Related Art In recent years, a black-and-white copying machine has been rapidly developed into a full-color copying machine, and the sales of two-color copying machines and digitized full-color copying machines also tend to increase in the market.

Generally, full-color image formation by electrophotography is performed in three primary colors of yellow, magenta and cyan.
Color reproduction is performed by using color toners of four colors or four colors in which black is added. As a method, first, an electrostatic latent image is formed on the photoconductive layer by passing light from the original through a color separation light transmitting filter having a complementary color relationship with the color of the toner. Next, the above-mentioned steps are sequentially performed a plurality of times, the toners are superposed on the same support while matching the registration, and the final full-color image is obtained by fixing only once.

Generally, a large number of developing methods are known in such an electrophotographic method, but in full-color developing, a magnetic brush method, a cascade method, etc. using a two-component developer mainly containing toner and carrier are used. Is widely used. All of these methods are excellent methods in which a good image can be obtained relatively stably, but on the other hand, they have common drawbacks associated with two-component developers, such as toner spent on the carrier surface and fluctuations in the mixing ratio of toner and carrier. .

In order to avoid such drawbacks, various developing methods using a one-component developer consisting of only toner have been proposed, but among them, the method using a developer consisting of magnetic toner particles has excellent performance. There are many things.

However, among the materials used for the magnetic toner, the magnetic material is usually 20% by weight with respect to the entire toner.
It is contained in an amount of up to 70% by weight and is considered to be a factor that greatly affects the performance of the toner. For example, as shown in JP-A-58-189646, a magnetic toner containing a magnetic powder having an FeO content of 16 to 25% by weight can surely obtain a high developing efficiency of an electrostatic image and a good transferring efficiency. However, due to the limitation of magnetic powder in full-color toner, it is used less frequently except when it is used only as black toner as a one-component toner, and it is a general-purpose product with a large number of continuous copies. Often used in black and white copiers, but ordinary color toners pass through the fixing process in a form close to complete melting using a very sharp melt binder resin and coloring agents such as dyes and pigments, resulting in an image Has a high surface smoothness and a highly glossy copy image can be obtained, whereas the magnetic toner used in the majority of black and white copiers contains magnetic powder in a proportion of about 20 to 70% by weight. Even after fixing apparently uniform image surface is rough state, if a low image gloss is obtained is almost.

On the other hand, in recent years, as a new user needs in the market due to the widespread use of such full-color copying machines, full-color copying machines, printers and the like are required to have the function of a black-and-white machine. In other words, in the office environment, there is a demand for a copying machine that can obtain a clear, high-quality full-color image while maintaining the color tone of black toner that has the same speed and quality as an ordinary general-purpose monochrome machine. It's coming.

In other words, it is desired that the black toner in the full-color copying machine also has a low gloss like the black-and-white copying machine so that a black image having the same texture can be obtained by all the different copying machines. Like a general-purpose monochrome machine,
Since the number of times the black toner is used alone is increased and the toner consumption is inevitably increased, the black toner in the full-color copying machine, which is required in the future, is required to be improved in terms of particularly excellent image quality and durability stability. There is.

The effect of such black toner means that the viscous term is more important as the fixing characteristic of the toner than the elastic term in the viscoelastic characteristic of the binder resin.

That is, when heated, the toner behaves more as a viscous material, the heat melting property is increased, and the glossiness is also obtained.

However, such a binder resin design emphasizing the viscosity term inevitably reduces intermolecular agglomeration at the time of heat melting, and also increases toner adhesion to the heat roller when passing through the fixing device. become. These cause a high temperature offset phenomenon.

In particular, when a silicone rubber roller is used as a fixing roller, high temperature offset is likely to occur due to the deterioration of the releasability of the surface of the silicone rubber roller, which is essentially used repeatedly regardless of whether or not the release oil is applied.
At the beginning of use of the silicone rubber roller, a certain degree of releasability can be maintained due to the smoothness and cleanliness of the roller surface. However, the image area is large like a color image, and the amount of toner held on a support such as plain paper is white.
When color copying, which is significantly larger than that of a black copied image, is continuously copied, the releasability of the roller gradually deteriorates. The speed of deterioration of the releasability reaches several times that of black and white copying.

Further, since the toner itself has almost no elasticity as described above, it is useless for the offset resistance effect. As a result, a toner coating or granular deposits are formed on the surface of the fixing roller after a few thousand to tens of thousands of sheets, and the toner upper layer portion of the image surface is peeled off when passing through the heat roller. So-called high temperature offset occurs.

Various measures have been attempted with toners in order to solve or alleviate the above problems, but further improvements are desired. For example, JP-A-55-60960,
JP-A-57-208559 and JP-A-58-119
53, JP 58-14144, JP 6
As described in JP-A-0-123852, a method of adding a low-molecular-weight polyethylene, polypropylene, wax, higher fatty acid, etc., which is a releasable component, to the toner is also used to increase the releasability. These methods are effective in preventing offset, but if they are contained in a large amount that is sufficiently effective in offset resistance, the compatibility with the main binder resin deteriorates and the transparency of the OHP image of the color toner is impaired. However, adverse effects such as instability of charging characteristics and deterioration of durability are also recognized, and it is difficult to say that the charging characteristics are sufficient.

Further, JP-A-47-12334, JP-A-57-37353, and JP-A-57-20855.
No. 9 discloses a monomer containing an etherified bisphenol monomer, a dicarboxylic acid monomer, a trivalent or higher polyhydric alcohol monomer and / or a trivalent or higher polyvalent carboxylic acid monomer. Although a toner containing a polyester composed of a non-linear copolymer obtained from the components as a binder has been proposed, such a technique is a polyester composed of an etherified bisphenol monomer and a dicarboxylic acid monomer,
Offsetting to the toner by incorporating a polyester obtained as a binder by crosslinking with a large amount of a monomer component containing a trivalent or higher polyhydric alcohol monomer and / or a trivalent or higher polyvalent carboxylic acid monomer It has preventive performance. However, in such a toner, its softening point is slightly high, so that it is difficult to perform good low-temperature fixing, and when a black toner using the polyester as a binder is used for full-color copying, the high-temperature offset resistance is Although it is at a level at which it can be put to practical use, since it is difficult to fix and sharp melt as described above, color mixing and color reproducibility cannot be expected. Further, JP-A-57-109825 and JP-A-62-78568.
In JP-A-62-78569 and JP-A-59-7960 and JP-A-59-29256, an etherified bisphenol monomer is used.
Including a dicarboxylic acid monomer into which a long-chain aliphatic hydrocarbon is introduced or another dicarboxylic acid monomer, and a trivalent or higher polyhydric alcohol monomer and / or a trivalent or higher polyvalent carboxylic acid monomer Disclosed is a toner which is a non-linear copolymer obtained from a monomer component and contains as a binder a polyester having a saturated or unsaturated aliphatic hydrocarbon group having 3 to 22 carbon atoms in its side chain. However, these polyester resins are mainly intended for high-speed copying toners, and the viscoelastic properties of the resin are, contrary to the above-mentioned viscoelastic polyester, to strengthen the elasticity and to be applied to the roller. The high temperature offset is remarkably reduced. Then, at the time of fixing, the pressure and heating of the heat roller are increased as much as possible, the toner is pressed in a semi-molten state between the fibers of the transfer paper, and pressure and heat fixing are performed to achieve the object. is there.

Therefore, it is almost impossible to obtain a smooth surface by melting the toner layer necessary for full-color copying, and the fixed toner exists in a particle state on the transfer paper to obtain the full-color image. The image is dull and has poor saturation. In an OHP image, the light is scattered and diffused on the surface of the toner particles, hardly transmitting the light, and practically unusable.

Further, Japanese Patent Laid-Open Nos. 2-73366 and 1-224776 disclose new polyester resins which are excellent in high temperature offset resistance and can be applied to color copying. Although it is superior to the conventional resin for color toner, the offset prevention effect to the fixing roller is exhibited at most about 20,000 copies repeatedly and the offset prevention effect of the black and white toner is 100,000 copies. The above is sufficient, and in view of having the printing durability and offset resistance of several hundred thousand sheets under the present circumstances, it is preferable to further improve the performance. Further, the polyester was studied with fixing property in color copying as a primary issue, and in terms of electrification, there is a large difference in electrification amount between a low temperature and low humidity environment and a high temperature and high humidity environment. In the color image, the density tends to be slightly low on the low humidity side, and toner scattering or fog may occur on the high humidity side.

Further, Japanese Patent Laid-Open No. 62-195676,
JP-A-62-195678 and JP-A-62-195.
Japanese Patent No. 680 discloses a polyester resin in which a ratio between a hydroxyl value and an acid value is specified. These polyester resins are also intended for high-speed fixing, but have been studied by the present inventors. The full-color toner using the resin did not reach a sufficient color mixing property.

As described above, in using the magnetic toner and the non-magnetic toner together in the developing process in the full-color copying machine,
The problems caused by the differences as indicated above must be resolved.

That is, in the magnetic toner, the dispersion state of the magnetic powder in the binder resin and the cleaning ability are regarded as problems, while in the non-magnetic toner, the dispersion of the colored dye / pigment in the binder resin and the improvement of the translucency. Is a problem. In addition, it is also an essential factor in such a case that both toners finally have excellent fixability after solving such a problem.

Furthermore, in a system in which magnetic toner and non-magnetic toner are mixedly mixed on the same image, there arises a problem that the surface smoothness of the fixed images of the magnetic toner and the non-magnetic toner is different. Magnetic powder contains 20 to 70 magnetic powder.
The mixture is mixed in a proportion of wt%, and the apparently uniform image surface is also in a rough state after fixing, whereas the non-magnetic toner containing the pigment is completely melted,
The surface smoothness is superior to that of magnetic toner. Because of this, the angle of reflection of the light that shows the luster that is visually appealing to the human eye is different, and while non-magnetic toner has high luster, magnetic toner has poor luster, and therefore, multi-color development produces images When obtaining an image, a problem occurs that the texture of the obtained image changes.

Further, as described above, the fixing characteristics of full-color toners, especially black toners, which will be used in future full-color copying machines, must be mainly improved.

That is, in order to satisfy the required characteristics required in the above, by using a binder resin of all color transition sharp-melt type, a very high level of image quality and fixing characteristics can be obtained in a pictorial image. However, during black-and-white copying, because of its sharp melt property, the glossiness is higher than that of images obtained by other black-and-white copying machines. There is a problem that offset or the like to the roller occurs.

[0024]

SUMMARY OF THE INVENTION An object of the present invention is to provide a full color toner and an image forming method which solve the above problems.

That is, an object of the present invention is to provide a full-color toner using four color toners, which has stable color reproduction, high image density and high durability, and an image forming method using the toner. In full-color copying, (1) shows good fixing property and color mixing property, (2) has sufficient triboelectrification property, and (3)
It has a high glossiness that significantly enhances image quality, (4) it is resistant to carrier spent even after repeated copying, and has excellent durability. (5) High temperature offset is sufficiently prevented, and the fixing temperature range is wide, (6) It is intended to provide a color toner whose offset resistance is maintained even after repeated fixing paper passes.

[0026]

The present invention achieves the above objects and provides the following first to fourth inventions. That is, the first is a full-color toner that forms a color image using at least one selected from yellow toner, magenta toner, and cyan toner as appropriate together with black toner. The above-mentioned yellow toner, magenta toner, and cyan toner Is a non-magnetic toner obtained by externally adding an external additive to colored resin particles formed by mixing and dispersing a colorant in a binder resin, and the binder resin is a diol component 45 selected from a bisphenol derivative or a substitution product. -55 mol% and 55-45 mol% of carboxylic acid component selected from dicarboxylic acid, its acid anhydride or its lower alkyl ester
And a polyester resin formed by polycondensation of 50, a hydroxyl value of 50 or less, a weight average molecular weight (Mw) of 6,000 to 100,000, and a number average molecular weight (Mn) of 1,500 to 50, 000, Mw / Mn is 4
The magnetic toner is obtained by externally adding magnetic additives to magnetic resin particles obtained by mixing and dispersing magnetic iron oxide powder containing 25 to 30% by weight of FeO and a release agent in a binder resin. A toner, wherein the binder resin is an aromatic dicarboxylic acid component 25 to 35 mol% selected from isophthalic acid, terephthalic acid, and derivatives thereof, trimellitic acid, and an aromatic tricarboxylic acid component selected from derivatives thereof. 2-4mo
1%, dodecenyl succinic acid, octyl succinic acid, and a dicarboxylic acid component 12 to 18 mo selected from its anhydride.
1% and a propoxylated and / or ethoxylated etherified diphenol component 45 to 60 mol% containing a polyester resin produced from a monomer composition, the hydroxyl value of the polyester resin is 10 to 20, Weight average molecular weight (Mw) is 13,000 to 20,000, number average molecular weight (Mn) is 5,000 to 8,000, Mw /
Mn is 2 to 3.5, which is a full-color toner.

The second is a full-color toner for forming a color image by selectively using at least one of yellow toner, magenta toner, cyan toner, and black toner, and the above-mentioned yellow toner, magenta toner, and The binder resin used for the cyan toner is a diol component 4 selected from a bisphenol derivative or a substitution product.
5 to 55 mol% and a carboxylic acid component 55 to 45 mol% selected from a dicarboxylic acid, an acid anhydride thereof or a lower alkyl ester thereof are polycondensed, and the hydroxyl value of the polyester resin is 50.
Hereinafter, the weight average molecular weight (Mw) is 6,000 to 100,
000, number average molecular weight (Mn) is 1,500 to 50,0
00, Mw / Mn is 4 to 6, and the binder resin used for the black toner is an aromatic dicarboxylic acid component 25 selected from isophthalic acid, terephthalic acid, and derivatives thereof.
-35 mol%, trimellitic acid and aromatic tricarboxylic acid component 2 to 4 mol% selected from its derivatives, dodecenyl succinic acid, octyl succinic acid, and dicarboxylic acid component 12 to 18 mol% selected from its anhydride, and A polyester resin produced from a monomer composition comprising 45 to 60 mol% of a propoxylated and / or ethoxylated etherified diphenol component is contained, and the hydroxyl value of the polyester resin is 10 to 20 and the weight average molecular weight (Mw). ) Is 13,000 to 20,000, the number average molecular weight (Mn) is 5,000 to 8,000, and Mw / Mn is 2 to
The full-color toner is 3.5.

Thirdly, by using the first full-color toner, at least one of yellow toner, magenta toner, and cyan toner is appropriately and selectively used together with the black toner, and the electrostatic charge on the electrostatic charge image carrier is selected. The image forming method is characterized in that the image is developed to form a toner image, and the toner image is sequentially transferred onto a transfer material to form an image.

Fourth, using the second full color toner, yellow toner, magenta toner, cyan toner,
And at least one of black toner is appropriately selected to develop an electrostatic charge image on the electrostatic charge image carrier to form a toner image, and the toner image is sequentially transferred onto a transfer material to form an image. And an image forming method.

The composition of the polyester resin used for the yellow toner, the magenta toner and the cyan toner constituting the first and third full color toners of the present invention is as follows.

The polyester resin is 4 out of all components.
5 to 55 mol% is a diol component, 55 to 45 m
ol% is a carboxylic acid component.

In this case, a bisphenol derivative represented by the following formula (I) or a substitution product thereof is used as the diol component.

[0033]

[Chemical 1] (In the formula, R is an ethylene or propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2
Further, as the carboxylic acid component, a dicarboxylic acid such as fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid or an acid anhydride thereof, or a lower alkyl ester. Is used.

The polyester resin obtained from the above-mentioned carboxylic acid and alcohol shows sharp melting characteristics,
As a full-color toner and heat roller fixing toner, it has good color mixing properties and excellent offset resistance.

Further, the glass transition temperature of the polyester resin obtained here is 50 to 75 ° C., preferably 55 to 65.
℃ is desirable.

Further, the number average molecular weight Mn is 1,500 to
50,000, preferably 2,000 to 20,000,
The weight average molecular weight Mw is 6,000 to 100,000, preferably 10,000 to 90,000, and Mw / M
n is 4-6.

The hydroxyl value is 50 or less, preferably 30 or less. This is because as the number of terminal groups in the molecular chain increases, the charging characteristics of the toner become more environmentally dependent.

It can be said that the polyester resin used in the black toner of the present invention has, so to speak, a transitional character in which the characteristics of both the linear polyester resin and the non-linear crosslinked polyester resin are combined. It is considered that, as a result, good color mixing and color reproducibility were obtained when used as a full-color toner, and offset resistance to the fixing roller was obtained.

That is, the reason why preferable characteristics are obtained by using a specific polyester resin for the black toner in the present invention is speculated as follows. (A) 20-30 units of one molecule of a divalent acid component and one molecule of a divalent alcohol component of trimellitic acid, which is a cross-linking monomer component, are regularly arranged in a repeating linear condensate chain at most. One molecule is introduced to form a weak crosslink. And, although it is the weak cross-linking, the entire condensate in the polyester is constituted as one three-dimensional polymer. This is much more offset resistant than just a mixture of linear polyesters. However, the cross-linking level of the present invention is also within the range that does not impede the easy heat-induced mobility of the polyester resin. (B) By extremely limiting the composition and amount of the divalent acid component having a soft segment, good results of color mixing and color reproducibility are obtained when a full-color image is obtained, and the offset resistance is adversely affected. I try to prevent it from happening. In the weak cross-linking condensate of the feature (a), the amount of the cross-linking acid component and the amount of the acid component are naturally determined so as to keep a balance. A decrease in gloss and saturation is seen in a color image.

In the present invention, a trivalent carboxylic acid is used as an essential component, but the molecular weight distribution is narrower than that of a usual cross-linking binder resin (Mw / Mn = 2 to 3.5, preferably 2.0 to 3). .0) can achieve the above effect. (C) Isophthalic acid or terephthalic acid is used as the other divalent acid component, and a composition having elasticity without decreasing the viscosity of the polymer is selected as much as possible. On the other hand, when changing to an aliphatic acid component, the molecular chain becomes linear and long, so it becomes easier for the molecular chain to move due to heat, and the polymer exhibits more viscous behavior. It becomes easier to offset to. (D) The production conditions of the polyester resin of the present invention are changed from the conventional ones, and the molecular weight distribution of the resin is particularly adjusted to be as sharp and narrow as possible. It is important to make the molecular chain distribution of the condensate in the polyester uniform within a narrow range in order to achieve both color mixing properties and offset resistance in the color toner. That is, a condensate having a short molecular chain with a small molecular weight is easily heated and the main chain of the molecule moves, while a condensate with a long molecular chain having a high molecular weight hardly moves by its thermal energy. When the imbalance exists in the polyester resin, when the color toner using the resin passes through the fixing roller at a low temperature,
A phenomenon occurs in which the low-molecular condensate quickly melts and behaves like fixing and color mixing, and the high-molecular condensate hardly dissolves.

On the other hand, when a temperature high enough to melt the polymer is applied to the fixing roller, the low molecule behaves as a viscous body having no elasticity at all, and causes a high temperature offset.

Therefore, particularly in full-color toners, the ratio of the weight average molecular weight to the number average molecular weight is increased in order to increase the intermolecular aggregation of the polyester resin constituting the toner while having a relatively sharp melt property. Should be as small as possible. This is a more important attribute than discussed with black and white toner. (E) In the characteristic (d), it has been stated that changing the production conditions of the polyester resin is indispensable for controlling the molecular weight distribution. However, in order to keep the hydroxyl value within a certain range, the production conditions are also changed. Is necessary. The hydroxyl value is a measure of the hydration property of the resin and is an important factor that influences the chargeability of the color toner. If the value is too large or too small, preferable charging characteristics cannot be obtained.

The value of the hydroxyl value is determined only by the production conditions of the composition of the polyester resin according to the present invention. However, the conditions (a) to (d) must be satisfied in order to combine both the fixing property and the charging property which satisfy the color mixing property, color reproducibility and offset resistance of the color toner.

The monomer composition and the like according to the present invention can be regarded as similar to the prior art at first glance, but the true aim of the present invention and the achievement point of the achieved technology are the conventional polyester resin and the color toner. It was something that could not be reached.

Therefore, in the black toner of the present invention, it is extremely difficult to achieve the object of the present invention unless the monomer components, composition ratios and various physical properties are within the ranges disclosed in the present invention.

The etherified diphenols preferred in the present invention are etherified bisphenols. Preferred etherified bisphenols are ethoxylated or propoxylated, having 2-3 moles of oxyethylene or oxypropylene per mole of bisphenol.

Colorants suitable for the purposes of the present invention include the following pigments or dyes. In the present invention, C.I. I. Disperse Y164; C.I. I. Solvent Y77 and C.I. I. Colorants such as Solvent Y93 are not recommended.

Examples of the dye include C.I. I. Direct Red 1; C.I. I. Direct Red 4; C.I. I. Acid Red 1; C.I. I. Basic Red 1; C.I. I.
Mordant Red 30; C.I. I. Direct Blue 1;
C. I. Direct Blue 2; C.I. I. Acid Blue 9; C.I. I. Acid Blue 15; C.I. I. Basic Blue 3; C.I. I. Basic Blue 5; C.I. I. Modant Blue 7 etc.

Examples of the pigment include Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NCG, Permanent Orange GTR, Pyrazolone Orange, Benzidine Orange G, Permanent Red 4R, Watching Red Calcium Salt, Brilliant Carmine 3B, Fast Violet B, Methyl Violet. Rake, phthalocyanine blue, fast sky blue, indanthrene blue BC, etc.

Disazo yellow, an insoluble azo pigment, and copper phthalocyanine are suitable as pigments, and basic dyes and oil-soluble dyes are suitable as dyes and pigments.

Particularly preferably, C.I. I. Pigment Yellow 17; C.I. I. Pigment Yellow 15; C.I. I. Pigment Yellow 13; C.I. I. Pigment Yellow 1
4; C.I. I. Pigment Yellow 12; C.I. I. Pigment Red 5; C.I. I. Pigment Red 3; C.I. I.
Pigment Red 2; C.I. I. Pigment Red 6;
C. I. Pigment Red 7; C.I. I. Pigment Blue 15; C.I. I. Pigment Blue 16 or a copper phthalocyanine-based pigment having the structural formula (II) shown below, in which the phthalocyanine skeleton is substituted with 2 to 3 substituents.

[0052]

[Chemical 2] Examples of the dye include C.I. I. Solvent Red 49; C.I.
I. Solvent Red 52; C.I. I. Solvent Red 109; C.I. I. Basic Red 12; C.I. I. Basic Red 1; C.I. I. For example, Basic Red 3b.

As for the content of yellow toner, which is sensitive to the transparency of the OHP film,
12 parts by weight or less based on 100 parts by weight of the binder resin,
It is preferably 0.5 to 7 parts by weight.

When the amount is 12 parts by weight or more, the reproducibility of green and red, which are mixed colors of yellow, and human skin color as an image is poor.

For other magenta and cyan color toners, the amount is 15 parts by weight or less, more preferably 0.1 to 9 parts by weight, based on 100 parts by weight of the binder resin.

The magnetic iron oxide powder having a FeO content of 25 to 30% by weight, which is used in the black toner of the first full-color toner of the present invention, has a high blackness as a black pigment,
The toner has a function of stabilizing the toner charge amount in order to maintain an appropriate electric resistance, can improve the image density, and has a function of improving the rank of fogging on the image in terms of developability.

When magnetic iron oxide having a FeO content of less than 25% by weight is used for the toner, it becomes difficult to control the toner charge amount properly in a low temperature and low humidity environment, especially when considering application to high speed machines. However, it is not possible to sufficiently cope with the image density reduction and the background stain due to the excessive increase of the toner charge amount, and it is difficult to control the color tone for obtaining a clear color tone as the black toner.

On the other hand, when the magnetic iron oxide having a FeO content of more than 30% by weight is used for the toner, the charge amount of the toner is reduced and the image density is reduced, especially in a high humidity environment.

This magnetic material has an average particle of 0.1 to 2 μm,
It is preferably about 0.1 to 0.5 μm,
The amount contained in the toner is about 20 to 200 parts by weight, preferably 10 parts by weight with respect to 100 parts by weight of the resin component.
40 to 150 parts by weight is preferable to 0 parts by weight.

The magnetic iron oxide used in the present invention is iron sulfate (F
eSO ₄ ) is neutralized with caustic soda (NaOH) and Fe (O
H) ₂ is obtained, and the pH is adjusted to 12 to 13 by adjusting the alkali, and then oxidized by steam and air to obtain a magnetite slurry. In the next drying process, the hot air dryer is used to control the drying temperature and the drying time, so that the FeO in the magnetic iron oxide is
Can be controlled. After the completion of drying, it is crushed to obtain magnetite powder.

Here, the measurement of FeO in magnetic iron oxide is carried out by the following procedure.

Into a 500 ml beaker, 1.000 g of magnetic iron oxide was added, 50 ml of deionized water was added, and 20 ml of special grade sulfuric acid was further added to completely dissolve the magnetic iron oxide.

Next, 100 ml of deionized water was added, and Mn was further added.
SO ₄ , H ₂ SO ₄ and H ₃ PO ₄ (molar ratio 0.3:
2.0: 2.0) was added to 10 ml of a mixed solution of MnSO ₄ to make a total of 180 ml, and then 10 ml was sampled.
Titrate with 1N KMnO ₄ solution.

Then, according to the following formula, 1.000 g of magnetic iron oxide
FeO (%) contained therein is determined.

[0065]

[Equation 1] Further, as the colorant for the black toner in the second full color toner of the present invention, carbon black having an average primary particle diameter of 50 to 70 mμ is used, and the carbon black has a surface area of 10
-40 m ² / g, oil absorption 50-100 cc / 100 g-
It is preferable that the DBP has a pH value of 6.0 to 9.0.

Particularly preferred ranges are 60 to 70 m, respectively.
μ, 30-40 m ² / g, 60-70 cc / 100 g-
It is DBP.

When the average particle diameter is less than 50 mμ, the frictional charge amount between the toner particles and the carrier particles decreases, which causes toner scattering and fog, and the surface area exceeds 40 m ² / g. The toner scattering phenomenon occurs at the edge portion of the obtained visible image, the oil absorption amount exceeds 100 cc / 100 g-DBP, and carbon black particles aggregate during image fixing, resulting in 50 cc / 1.
If it is less than 00g-DBP, a sufficient image density cannot be obtained. Further, if the pH value is less than 6.0, the dispersion of carbon black in the binder resin becomes non-uniform, resulting in unstable charging ability.

In measuring the physical properties of the above carbon black, the particle size was measured by directly and selectively counting the particle sizes in a scanning electron micrograph. Next, surface area, oil absorption,
The method for measuring the pH value will be described. The measurement of surface area is
It is performed in accordance with the BET formula in ASTM method D3037-78.

A mixed gas of N ₂ and He is caused to flow through the carbon black to adsorb N ₂ and the amount thereof is detected by a thermal conductivity cell, and the specific surface area of the sample is calculated from the N ₂ adsorption amount. 1) The sample is dried at 105 ° C. for 1 hour, then precisely weighed 0.1 to 1 g, put in a U-shaped tube 14 and attached to the flow path. 2) The N ₂ / He mixture ratio is changed by the flow rate controllers 10 and 11 and set to a predetermined P / P ₀ . 3) Open the cock to introduce the adsorption gas into the sample layer, and then dip the U-shaped tube in the liquid N ₂ 13 to adsorb N ₂ . 4) After reaching the adsorption equilibrium, remove the liquid N ₂ and expose it to the air for about 30 seconds, then soak the U-tube in water at room temperature for N
Detach ₂ 5) Draw the desorption curve on the recorder and measure the area. 6) Prior to these operations, a calibration curve prepared by introducing a known amount of N ₂ was used to determine the N ₂ adsorption amount at a predetermined P / P ₀ from the area obtained for the above sample.

Below, the surface area is obtained by applying the following equation.

[0071]

[Equation 2] P ₀ : Saturated vapor pressure of the adsorbate at the measurement temperature P: Pressure at adsorption equilibrium ν: Adsorption amount at adsorption equilibrium C: Constant The relation between P / P ₀ and P / ν (P ₀ −P) is a straight line,
Calculate ν _m from the slope and intercept. If ν _m is obtained, the specific surface area S is calculated by the following equation.

S = A × ν _m × N / W where S: specific surface area A: cross-sectional area of adsorbed molecule N: Avogadro's number W: sample amount oil absorption (DBP method) Oil absorption is measured by ASTM method D2414-79. According to. Operate the cock of the absorber meter to completely fill the automatic buret system with DBP (dibutyl phthalate) so that no air bubbles remain, and make the specifications of the device as follows.

(1) Spring tension
2.68 kg / cm (2) Rotor speed 125 rpm (3) Scale of limit switch for torque 5 (4) Damper valve 0.150 (5) Dripping speed of DBP 4 ml / m
After the dropping rate of in DBP is adjusted by actual measurement, a fixed amount of a dry sample is put into the absorption meter mixing chamber, the burette counter is set to 0 point, and the switch is automatically started to start dropping. When the torque reaches the set point (5 in this case), the limit switch operates and the drip stops automatically.
The scale (V) of the burette counter at that time is read, and the oil absorption is calculated by the following formula.

OA = (V / W) × 100 OA: oil absorption (ml / 100 g) V: DB used up to the end point (limit switch operating point)
Amount of P (ml) W: Weight of dried sample (g) pH value Weigh 1-10 g of carbon black into a beaker, add water at a rate of 10 ml per 1 g of sample, cover with a watch glass, and boil for 15 minutes. . A few drops of ethyl alcohol may be added to make the sample wettable. After boiling, cool to room temperature and remove the supernatant by decantation or centrifugation.
Leave mud. An electrode of a glass electrode pH meter is put in this mud and the pH is measured according to JIS Z8802 (pH measuring method). In this case, the measured value may change depending on the insertion position of the electrode.Move the beaker to change the position of the electrode and carefully measure it so that the electrode surface and the mud-like surface are in sufficient contact. Read the value when is constant.

In the present invention, carbon black is 2.0 to 10% by weight, preferably 3.
It is preferable to use 0 to 7% by weight. If the amount of carbon black added is less than 2.0% by weight, in the obtained visible image, the image becomes rough and the image density decreases, and conversely 1
If the content is more than 0% by weight, it may cause scattering and fogging on the image.

The carrier used in the present invention includes, for example, surface-oxidized or non-oxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, chromium and rare earths, their alloys or oxides and magnetic ferrites. Can be used. Moreover, there is no particular limitation in the manufacturing method.

A system in which the surface of the carrier is immersed in a resin or the like is particularly preferable. As the method, any conventionally known method such as a method of dissolving or suspending a coating material such as a resin in a dissolving agent and applying the coating material and attaching it to a carrier, or a method of simply mixing with a powder can be applied.

The substance adhered to the surface of the carrier varies depending on the toner material. For example, polytetrafluoroethylene, monochlorotrifluoroethylene polymer, polyvinylidene fluoride, silicone resin, polyester resin, styrene resin, acrylic resin, polyamide, Polyvinyl butyral, nigrosine, amino acrylate resin,
It is suitable to use a basic dye and its lake, a fine silica powder, a fine alumina powder, a metal complex or a metal salt of dialkylsalicylic acid alone or in combination.

The amount of the above-mentioned compound to be treated may be appropriately determined so that the carrier satisfies the above-mentioned conditions, but generally, the total amount is 0.1 to 30% by weight (preferably 0.5 to 10%) based on the carrier of the present invention. 20% by weight) is preferred.

The average particle size of these carriers is 20 to 100.
μm, preferably 25 to 70 μm, more preferably 25
It is preferable to have ˜65 μm.

In a particularly preferred embodiment, Cu-Zn-
It is a ternary ferrite of Fe, and the surface thereof is a combination of resins such as fluorine resin and styrene resin, for example, polyvinylidene fluoride and styrene-methyl methacrylate resin; polytetrafluoroethylene and styrene-methyl methacrylate resin; Fluorine-based copolymer; etc. 90:10 to 20:80, preferably 70:30 to 3
A mixture in a ratio of 0:70 is coated in an amount of 0.01 to 5% by weight, preferably 0.1 to 1% by weight.
An example is a coated magnetic ferrite carrier having the above-mentioned average particle size in which carrier particles of 50 mesh pass and 350 mesh on are 70% by weight or more. Examples of the fluorine-based copolymer include vinylidene fluoride-tetrafluoroethylene copolymer (10:90 to 90:10), and examples of the styrene-based copolymer include styrene-2-ethylhexyl acrylate copolymer (20 : 80-80: 2
0), a styrene-acrylic acid-ethylhexyne-methyl methacrylate copolymer (20-60: 5-30: 10).
50) is exemplified.

The above-mentioned coated ferrite carrier has a sharp particle size distribution, and it is possible to obtain a preferable triboelectrification property for the toner of the present invention and to improve electrophotographic characteristics.

When a two-component developer is prepared by mixing with the full-color toner of the present invention, the mixing ratio is 1% by weight to 15% by weight, preferably 2% by weight as the toner concentration in the developer.
Good results are usually obtained with a weight percentage of 13 to 13%. If the toner concentration is less than 1% by weight, the image density will be low, and if it exceeds 15% by weight, fog and in-machine scattering will increase, and the useful life of the developer tends to be shortened.

In the first full-color toner of the present invention, yellow toner, magenta toner, and cyan toner are
Further, in the second full-color toner, it is desirable to further add titanium oxide fine particles having a weight average particle diameter of 0.01 to 0.2 μm to the black toner. Although hydrophobic silica, which is generally known as a flow improver, improves initial cleaning characteristics or toner fluidity, but cannot maintain initial cleaning characteristics or environmental characteristics without stabilization of toner charge. was difficult. However, by using the titanium oxide fine particles, it is possible to stabilize the charging, improve the fluidity, and improve the cleaning property or the environmental property.

Further, in order to surely exhibit the above-mentioned performance and to have stable charging characteristics, it is preferable that the titanium oxide fine particles are contained in an amount of 0.5 to 1.0% by weight based on the toner.

As titanium oxide fine particles particularly suitable for the present invention, it is preferable to use titanium oxide fine particles which have been surface-treated while hydrolyzing the coupling agent in an aqueous system.

Further, if necessary, a fatty acid metal salt as a lubricant, such as zinc stearate or aluminum stearate, or a fine powder of a fluorine-containing polymer, such as polytetrafluoroethylene, polyvinylidene fluoride or the like and tetrafluoroethylene- Fine powder of vinylidene fluoride copolymer or a conductivity-imparting agent such as tin oxide or zinc oxide may be added.

The first full-color toner of the present invention preferably contains a flow improver as an external additive.

As such a fluidity improver, any fluidity improver can be used as long as it can be added to the colorant-containing resin particles and the fluidity can be increased before and after the addition.
For example, hydrophobic colloidal silica fine powder, colloidal silica fine powder, hydrophobic titanium oxide fine powder, titanium oxide fine powder, hydrophobic alumina fine powder, alumina fine powder, mixed powder thereof, etc. In view of this, a BET specific surface area of 50 m ² / g or more is preferable.

Particularly, as the fluidity improver which can be contained in the black toner, silica fine powder having a weight average diameter of 0.001 to 2 μm is preferable.

As the silica fine powder, wet process silica,
There are dry-process silicas, silane coupling agents, titanium coupling agents, treated silicas that have been surface-treated with silicone oil, and the like, but preferred silica fine powders are those produced by vapor phase oxidation of silicon halogen compounds. It is a fine powder, so-called dry process silica or fumed silica, which is produced by a conventionally known technique. For example, the thermal decomposition oxidation reaction of silicon tetrachloride gas in oxyhydrogen flame is utilized, and the basic reaction formula is as follows.

SiCl ₄ + 2H ₂ + O ₂ → SiO ₂ + 4HCl Further, in this manufacturing process, by using another metal halogen compound such as aluminum chloride or titanium chloride together with a silicon halogen compound, a fine composite powder of silica and another metal oxide is obtained. It is also possible to obtain the body, including them.

The particle size is 0.0 as the average primary particle size.
It is desirable to be in the range of 01 to 2 μm, and it is particularly preferable to use fine silica powder in the range of 0.002 to 0.2 μm.

Examples of commercially available silica fine powders produced by vapor phase oxidation of a silicon halogen compound used in the present invention include those commercially available under the following trade names.

Aerosil Japan Aerosil Japan 130 200 300 380 TT600 MOX170 MOX80 COK84 Ca-O-SiL Cabot Co. (CABOT Co.) M-5 MS-7 MS-75 HS-5 EH-5 Wacker HDK N20V15 Wacker-Chemie company N20E (WACKER-CHEMIE GMBH) T30 T40 DC Fine silica (Fine Silica) Dow Corning Co. Fransol Fransil Further, it is more preferable to use a treated silica fine powder obtained by subjecting the silica fine powder produced by the vapor phase oxidation of the silicon halogen compound to a hydrophobic treatment. Among the treated silica fine powders, those obtained by treating the silica fine powder so that the degree of hydrophobicity measured by the methanol titration test is in the range of 30 to 80 are particularly preferable.

As a method of hydrophobizing, reaction with fine silica powder is carried out,
Alternatively, it is provided by chemically treating with an organic silicon compound that physically adsorbs.

As a preferred method, silica fine powder produced by vapor phase oxidation of a silicon halogen compound is treated with an organosilicon compound.

Examples of such organosilicon compounds are hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyl. Dimethylchlorosilane, brommethyldimethylchlorosilane, α-chloroethyltrichlorosilane, ρ-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilylmercaptan, trimethylsilylmercaptan, triorganosilylacrylate, vinyldimethylacetoxysilane, dimethylethoxy Silane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldi Siloxane, 1,3-diphenyltetramethyldisiloxane, and dimethylpolysiloxane having 2 to 12 siloxane units per molecule and having a terminally located unit each containing a hydroxyl group bonded to Si. . These are used alone or in a mixture of two or more.

The particle size of the treated silica fine powder is
It is preferable to use one having a range of 0.003 to 0.1 μm. Commercially available products include Talanox-500 (Tarco) and Aerosil R-972 (Japan Aerosil).

The amount added to the magnetic resin particles is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the resin particles. If it is 0.01 part by weight or less, the fluidity is not improved, and if it is 10 parts by weight or more, fog or character bleeding and scattering in the machine are promoted.

Further, the magnetic black toner according to the first full-color toner of the present invention contains a release agent. The intention is that by defining the molecular weight distribution of the binder resin in an appropriate range, the offset resistance is also good, and the magnetic powder is well dispersed in the binder resin, and a high-concentration visible image can be obtained. However, if magnetic and non-magnetic toners are present on the same latent image carrier as in the constitution according to the present invention, the fixing properties of both toners are different, and after fixing, the layer surface is relatively Compared to non-magnetic toner that can maintain a smooth state, the surface of the magnetic toner layer is in a rough state, so when the transfer material such as paper and sheet is peeled off from the fixing heating roller, releasability is improved. Is better, and the addition of an auxiliary release agent leads to a further improvement in fixing property.

Thus, the releasing agent used in the present invention has a melting start temperature of 40 ° C. or higher, preferably 50.
It has a melting point of at least 2 or more between 50 ° C. or higher and 50 to 250 ° C., preferably 70 to 200 ° C. as measured by DSC, or two or more kinds having different melting points are mixed and used. it can. This is because when the melting start temperature of the release agent is 40 ° C. or lower, blocking resistance is poor, and those having a plurality of melting points in the range of 50 to 250 ° C. release from a low temperature to a high temperature over a wide range. This is because the mold effect can be exhibited. Furthermore, as a more preferable method of using the releasing agent for the binder resin used in the present invention, two types of releasing agents having different melting points and having no polar group and a releasing agent having a polar group are used. It is desirable to use a combination of the above. This is because when the binder resin of the present invention is used, most of the non-polar release agent is present in the matrix resin, and conversely, most of the release agent having a polar group is present in the domain resin. By doing so, it has a releasing effect on both the matrix resin and the domain resin. Therefore, as long as it can exist in the matrix resin and the domain resin and has a plurality of melting points in the range of 50 to 250 ° C., there is no problem even if only one type of release agent is used.

Examples of the releasing agent having no polar group used in the present invention include the following. Aliphatic hydrocarbon wax such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, paraffin wax, oxide of aliphatic hydrocarbon wax such as oxidized polyethylene wax, or block copolymer thereof, carnauba Examples thereof include waxes containing a fatty acid ester as a main component such as wax, sazol wax, and montanic acid ester wax, and those obtained by partially or entirely deoxidizing fatty acid ester such as deoxidized carnauba wax. The release agent having a polar group used in the present invention includes the following. Palmitic acid, stearic acid, montanic acid, and the like, saturated straight-chain fatty acids, brandic acid, eleostearic acid, unsaturated fatty acids such as valinaric acid, stearyl alcohol, alkyl alcohol, behenyl alcohol, carnaubayl alcohol, ceryl alcohol, Saturated alcohols such as melicyl alcohol, polyhydric alcohols such as sorbitol, fatty acid amides such as linoleic acid amide, oleic acid amide, and lauric acid amide, methylenebisstearic acid amide,
Saturated fatty acid bisamides such as ethylenebiscapric acid amide, ethylenebislauric acid amide, hexamethylenebisstearic acid amide, ethylenebisoleic acid amide, hexamethylenebisoleic acid amide, N, N '
-Unsaturated fatty acid amides such as dioleoyl adipamide, N, N'-dioleyl sebacic amide, m-
Aromatic bisamides such as xylenebisstearic acid amide and N, N′-distearylisophthalic acid amide,
Fatty acid metal salts such as calcium stearate, calcium laurate, zinc stearate, magnesium stearate (generally called metal soap), and aliphatic hydrocarbon waxes using vinyl monomers such as styrene and acrylic acid. Examples thereof include grafted waxes, partial esterified products of fatty acids such as behenic acid monoglyceride and polyhydric alcohols, and methyl ester compounds having a hydroxyl group obtained by hydrogenation of vegetable oils and the like.

The amount of the release agent used in the present invention is 0.1 to 20 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the binder resin. If the amount of the release agent is 20 parts by weight or more, the blocking resistance and the high temperature offset are poor, and If it is less than 1 part by weight, there is no release effect.

Further, these releasing agents are usually contained in the binder resin by a method of dissolving the resin in a solvent, raising the temperature of the resin solution, and adding and mixing while stirring, or a method of mixing at the time of kneading.

In the multicolor developing method in which images are sequentially formed on the latent image carrier using these full color toners, in the present invention, the black toner is developed on the latent image carrier in the first order and then in the second order. After the eyes, it is desirable to sequentially develop a cyan toner, a yellow toner, and a magenta toner to control multiple image formation. In the case of the black-and-white dual-purpose copying machine according to the present invention, there are many opportunities to obtain a continuous copy image in a black single color, and if so-called coalescence between particles is performed, the fixing characteristic has two peaks. It is desirable to use a harder binder resin as a medium. However, when copying a pictorial image such as a full-color image, a clear tint is required, and inevitably a binder resin that is relatively easy to melt is desired in order to facilitate color mixing.

In the above cases, in order to satisfy both, the influence of the surface glossiness due to the difference in the binder resin as shown in FIGS. 1 and 3 is a factor greatly influenced.

Therefore, when the magenta toner was developed in the first order, and the cyan toner, the yellow toner, and the black toner were successively developed, the conventional multicolor development was performed, and the full color toner of the present invention was used. In this case, the black toner in the uppermost layer hinders the glossiness of the three colors in the lower layer, and in a full-color image in which four colors are superposed, different glossinesses are generated in various parts of the image area. Will result. From the above, in the present invention, by obtaining a multicolor image in a proper development order, a black toner having low gloss is formed on the lowermost layer on the transfer paper to prevent irregular reflection of light and to obtain a uniform gloss. It is possible to obtain a full-color image having

A charge control agent may be added to the full-color toner of the present invention in order to stabilize the charging characteristics. At that time, a colorless or pale color charge control agent that does not affect the color tone of the toner is preferable. In the present invention, when a negatively chargeable developer is used, the present invention becomes more effective. Examples of the negatively charge control agent in that case include metal complexes of alkyl-substituted salicylic acid (for example, chromium of di-tert-butylsalicylic acid). Complexes or zinc complexes).
When compounding the negative charge control agent with the toner, the binder resin 10
0.1 to 10 parts by weight, preferably 0.
It is preferable to add 5 to 8 parts by weight.

The method of measuring each physical property value according to the present invention will be described below.

(1) Measurement of glass transition temperature Tg In the present invention, measurement is carried out using a differential thermal analysis measuring device (DSC measuring device), DSC-7 (manufactured by Perkin Elmer).

The measurement sample is 5 to 20 mg, preferably 10
Precisely weigh mg.

This is put in an aluminum pan, an empty aluminum pan is used as a reference, and the following operation is performed for the purpose of first erasing the previous history. Room temperature to 200 in N ₂ atmosphere
The temperature is raised to 10 ° C./min and kept at 200 ° C. for 10 minutes. Then, it is rapidly cooled, the temperature is lowered to 10 ° C., and the temperature is kept at 10 ° C. for 10 minutes. Then, at a heating rate of 10 ° C./min, 2
Raise the temperature to 00 ° C. During this temperature raising process, the temperature of 40 to 10
The endothermic peak of the main peak in the range of 0 ° C is obtained.

The crossing point between the line at the midpoint of the baseline before and after the appearance of the endothermic peak at this time and the differential heat curve is taken as the glass transition temperature Tg in the present invention (see FIG. 2).

(2) Method for measuring GPC In the present invention, the molecular weight distribution of the chromatogram by GPC (gel permeation chromatography) using THF as a solvent is measured under the following conditions.

That is, the column is stabilized in a heat chamber at 40 ° C., and THF (tetrahydrofuran) as a solvent is flowed through the column at this temperature at a flow rate of 1 ml / min, and about 100 μl of a THF sample solution is injected for measurement. .
In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of the calibration curve prepared using several kinds of monodisperse polystyrene standard samples and the count number.
As a standard polystyrene sample for preparing a calibration curve, for example, a molecular weight of 10 ² manufactured by Tosoh Corporation or Showa Denko KK
Used of about 10 ^7, it is appropriate to use at least about 10 standard polystyrene samples. An RI (refractive index) detector is used as the detector. As the column, it is preferable to combine a plurality of commercially available polystyrene gel columns, for example, Shodex GPC KF-801, 802, 80 manufactured by Showa Denko KK
Combination of 3,804,805,806,807,800P and TSKgel G1000H manufactured by Tosoh Corporation
(H _XL ), G2000H (H _XL ), G3000H
(H _XL ), G4000H (H _XL ), G5000H
(H _XL ), G6000H (H _XL ), G7000H
(H _XL ), TSK guard column (guard column)
The combination of n) can be mentioned.

The sample is prepared as follows.

The sample is placed in THF, left to stand for several hours, shaken thoroughly and mixed well with THF (until the coalescence of the sample disappears), and then allowed to stand for 12 hours or more. TH at this time
The time for leaving in F should be 24 hours or more. Then sample processing filter (pore size 0.45-0.45)
0.5 μm, for example, Mysholydisc H-25-6
A product of Tosoh Corp., Excicrodisc 25CR Gelman Science Japan Corp., etc.) can be used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 to 5 mg / ml. (3) Measurement of hydroxyl value: The hydroxyl value is measured by the following method according to the method described in JIS K007.

A 6 ml sample was placed in a 200 ml Erlenmeyer flask for 1 m.
Weigh accurately in g units, add a mixed solution of acetic anhydride / pyridine = 1/4 with a 5 ml hole pipette, and add 25 m of pyridine.
Add 1 with a graduated cylinder. A condenser is attached to the Erlenmeyer flask mouth, and the reaction is performed in an oil bath at 100 ° C. for 90 minutes.

3 ml of distilled water was added from the upper part of the cooler, shaken well and left for 10 minutes. With the condenser attached, the Erlenmeyer flask is pulled up from the oil bath and allowed to cool. When the temperature reaches about 30 ° C., the condenser and the flask outlet are washed with a small amount of acetone (about 10 ml) from the condenser upper opening. THF50
ml is added with a graduated cylinder, and neutralization titration is carried out using a 50 ml (scale 0.1 ml) burette with an N / 2KOH-THF solution using an alcohol solution of phenolphthalein as an indicator. 25 ml of neutral alcohol just before the end point of neutralization
(Methanol / acetone = 1/1 volume ratio) is added and titration is carried out until the solution becomes slightly red. At the same time, perform a blank test.

Then, the hydroxyl value is calculated according to the following formula.

[0122]

[Equation 3] Where A: ml of N / 2KOH-THF solution required for this test B: ml of N / 2KOH-THF solution required for blank test f: titer of N / 2KOH-THF solution S: sampled amount (G) C: acid value or alkali value. However, the acid value is positive and the alkali value is negative.

The average value of the two measured values is adopted.

(4) Gloss (glossiness) measuring method: VG-1
Using a 0 type gloss meter (manufactured by Nippon Denshoku Co., Ltd.), each solid image used for chromaticity measurement is used as a sample for measurement.

For the measurement, first, 6 V was measured by a constant voltage device.
Set to.

Then, the light projecting angle and the light receiving angle are respectively set to 60.
Set to °.

Using the 0-point adjustment and standard plate, after the standard setting, the sample image is placed on the sample table, and the white paper is 3
Perform overlay measurement on a sheet and read the value shown in the marking section in%.

At this time, the S / S / 10 switch SW is set to S, and the angle / sensitivity switch SW is set to 45-60.

A sample having an image density of 1.5 ± 0.1 is used.

[0130]

[Examples] Examples of the present invention will be given below, but all "parts" and "%" are "parts by weight" and "% by weight".

Example 1 Polyester resin obtained by condensing 100 parts of propoxylated bisphenol and fumaric acid (Mn = 4000, Mw = 16000, Tg = 57 ° C., acid value = 6.7, OH value = 15) .6) C.I. I. Pigment Yellow 17 3.5 parts Di-tert-butylsalicylic acid chromium complex salt 4 parts After thoroughly premixing with a Henschel mixer,
The mixture was melt-kneaded with a twin-screw extruder, cooled, and then coarsely pulverized with a hammer mill to a particle size of about 1 to 2 mm. Then, it was pulverized by an air jet pulverizer. Further, the obtained finely pulverized product was classified by a multi-division classifier to obtain yellow resin particles having a weight average particle diameter of 8.0 μm.

With respect to 100 parts of the yellow resin particles, 0.7 part of hydrophilic titanium oxide (BET 70 m ^{2 /} g) synthesized from titanium chloride and an average particle size of 0.4 μm were used.
0.5 parts of spherical methyl methacrylate resin particles of No. 1 were combined to obtain a yellow toner.

Next, C. I. Pigment Yellow 17 was replaced with 4 parts of rhodamine-based pigment in the same manner as yellow toner to obtain magenta toner.

Next, C. I. Pigment Yellow 17 was replaced with 5 parts of a phthalocyanine pigment represented by the following structural formula to prepare a cyan toner in the same manner as the yellow toner.

[0135]

[Chemical 3] The yellow, magenta, and cyan toners were mixed with Cu-Zn-Fe ferrite particles whose surface was coated with a methyl methacrylate-butyl acrylate (75:25) copolymer so as to have a toner concentration of 5%, and developed. I used it as an agent.

Next, C. I. Pigment Yellow 17, FeO content 26.1%, specific surface area 8.1 m ² /
g, 60 parts of magnetite having a bulk density of 0.44 g / cm ³ was used, the following resin (A) was used as a binder resin, and a low molecular weight polyethylene wax (melting point 123 ° C, melting start temperature 75 ° C) was used as a release agent. Parts and calcium laurate (1
Melting point peaks at 06,125,142,160 ° C,
Melting start temperature 80 ° C) 2.0 parts, and 0.5 parts of silicic acid fine powder (BET 230 m ^{2 /} g) hydrophobized with hexamethyldisilazane as additives and 0.5 parts of strontium titanate are used. To obtain a black magnetic toner.

(Polyester resin A) terephthalic acid 2 m
ol, dodecenyl succinic anhydride 1.09 mol, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 3.4 mol, and 0.01 g of dibutyltin oxide were added to a glass 21 four-necked flask. Then, a thermometer, a stirring rod, a condenser, and a nitrogen introducing tube were attached and placed in the mantle heater. Next, after replacing the inside of the flask with nitrogen gas, gradually raising the temperature while stirring,
The reaction was carried out at 170 ° C. for 5 hours, then the temperature was raised to 190 ° C., and the reaction was carried out for 4 hours. The hydroxyl value of the resin produced at this point was 59.8.

Then, trimellitic anhydride 0.2mo
1 and 0.08 g of dibutyltin oxide were added, and 190
The reaction was carried out at 0 ° C for a further 3 hours, the temperature was further raised to 200 ° C, the reaction was carried out for 5 hours, and the reaction was completed to obtain polyester resin (A).

At that time, the hydroxyl value was 16.8, the glass transition temperature was 64 ° C., the weight average molecular weight was 16000, the number average molecular weight was 5900, and the ratio was 2.7.

Commercially available color copying machine (CLC-500 made by Canon) using the above three kinds of developers and black magnetic toner.
Is modified so that images can be output in the order of black, cyan, yellow, and magenta, and the development contrast is set to 3
Image evaluation was carried out at a constant 50 V, but even after a durability test of 50,000 full-color images, there was a clear tint, the image quality did not change significantly, and no background fog was observed. The density was as high as 1.4 to 1.5 for each color, and no cleaning failure was observed after endurance.

Further, a durability test of 30,000 sheets was conducted using only the black toner, but no toner fusion to the photosensitive member was observed,
No offset to the surface of the fixing roller was also confirmed.

Example 2 In Example 1, the magnetite in the black toner had an FeO content of 28.1%, a specific surface area of 7.4 m ² / g and a bulk density of 0.46 g / cm ³ , The same evaluation was performed except that the binder resin used was the resin shown in (B) below, and a stable high image density was obtained, and the durability evaluation of 80,000 full-color images and 50,000 black images was obtained. However, no offset or cleaning failure was observed.

(Polyester Resin B) Isophthalic Acid 1.
8 mol, dodecenyl succinic anhydride 1.06 mol, polyoxypropylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 3.5 mol Binder resin A
The reaction was conducted in a nitrogen atmosphere in the same manner as in. Then, 0.16 mol of trimellitic anhydride and 0.09 g of dibutyltin oxide were added and the reaction was carried out at 180 ° C. for 5 hours to obtain the polyester resin (B) of the present invention. At that time, the hydroxyl value was 18.5, the glass transition temperature was 63 ° C., the weight average molecular weight was 17,000, the number average molecular weight was 5800, and the ratio was about 2.9.

(Example 3) In Example 1, yellow,
As the hydrophilic titanium oxide contained in each of magenta and cyan toners, 0.5 part of hydrophilic titanium oxide (BET 120 m ² / g) synthesized from titanium isopropoxide is used, and a binder resin used for black toner. When the same evaluation was performed except that the resin was a resin shown in (C) below, neither offset nor cleaning failure was observed, and stable image quality was obtained.

(Polyester resin C) terephthalic acid 2 m
ol, octyl succinic acid 1.15 mol, and polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 3.6 mol were reacted in the same manner as polyester resin A in a nitrogen atmosphere. Then, 0.18 mol of trimellitic anhydride and 0.08 g of dibutyltin oxide were added and the reaction was carried out at 180 ° C. for 5 hours to obtain the polyester resin (C) of the present invention.

The hydroxyl value of this resin was 16.5, the glass transition temperature was 64 ° C., the weight average molecular weight (Mw) was 17,000, and the number average molecular weight (Mn) was 6300. Mw / Mn was about 2.
It was 7.

(Polyester resin D) 2.0 mol of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2.
0) -2,2-bis (4-hydroxyphenyl) propane 2.1 mol, terephthalic acid 2 mol, dodecenyl succinic acid 1.6 mol, trimellitic acid 0.46 mol were used at 250 ° C. using the same device as the polyester resin (A).
The polyester resin (D) of the present invention was obtained by reacting for 8 hours.

The hydroxyl value of this resin was 20.4, the weight average molecular weight (Mw) was 110000, and the number average molecular weight (Mw) was 5.
540 and Mw / Mn was about 19.9. The glass transition temperature was 61.5 ° C.

(Example 4) The same procedure as in Example 1 was repeated except that 0.5 part of titanium oxide obtained by hydrophobizing hydrophilic titanium oxide with dimethyl silicone oil was used as the external additive used for the black toner. As a result, toner adhesion to the photosensitive member did not occur, and no significant change was observed in the image quality even when the black image was subjected to the durability test of 50,000 sheets.

(Comparative Example 1) The same evaluation as in Example 1 was carried out except that images were developed in the order of magenta, cyan, yellow, and black, and the durability of full-color images and black images was evaluated. No defective cleaning, offset, etc. were observed even after the test, but in the case of a full-color image, the gloss of the gray image was insufficient and the tint was impaired, resulting in deterioration of the overall image quality.

(Comparative Example 2) In Example 1, yellow,
The same evaluation was performed except that the binder resin used for each of the magenta and cyan toners was the polyester resin D, but the color mixture was not sufficient in the full-color image due to insufficient melt fixing at the time of fixing, and the tint was disturbed. Then, offset occurred in the durability test of about 5,000 sheets.

(Comparative Example 3) Example 1 is the same as Example 2 except that the hydrophilic titanium oxide as the fluidity improver used in the color toner and the black toner is excluded from the toner.
The same evaluation as above was performed, but in a high humidity environment (30 ° C / 8
Fog occurred on the white background at 0% RH).

Example 5 Polyester resin obtained by condensing 100 parts of propoxylated bisphenol and fumaric acid (Mn = 4000, Mw = 16000, Tg = 57 ° C., acid value = 6.7, OH value = 15) .6) C.I. I. Pigment Yellow 17 3.5 parts Di-tert-butylsalicylic acid chromium complex salt 4 parts After thoroughly premixing with a Henschel mixer,
The mixture was melt-kneaded with a twin-screw extruder, cooled, and then coarsely pulverized with a hammer mill to a particle size of about 1 to 2 mm. Then, it was pulverized by an air jet pulverizer. Further, the obtained finely pulverized product was classified by a multi-division classifier to obtain yellow resin particles having a weight average particle diameter of 8.0 μm.

Titanium oxide (BET 90 m ² / g) obtained by hydrophobizing hydrophilic titanium oxide synthesized from titanium chloride to 100 parts of the yellow resin particles was 1.
The yellow toner was combined with 0 part.

Next, C. I. Pigment Yellow 17 was replaced with 4 parts of rhodamine-based pigment in the same manner as yellow toner to obtain magenta toner.

Next, C. I. Pigment Yellow 17 was replaced with 5 parts of a phthalocyanine pigment represented by the following structural formula to prepare a cyan toner in the same manner as the yellow toner.

[0157]

[Chemical 4] The yellow, magenta, and cyan toners were mixed with Cu-Zn-Fe ferrite particles whose surface was coated with a methyl methacrylate-butyl acrylate (75:25) copolymer so as to have a toner concentration of 5%, and developed. I used it as an agent.

Next, C. I. Pigment Yellow 17 has an average particle size of 60 μm and a surface area of 30 m ² / g oil absorption 6
A black toner was obtained by using 3.5 parts of carbon black having a physical property value of 5 cc / 100 g and a pH value of 8.0 and using the polyester resin A as a binder resin.

Commercially available color copying machines (CLC-500) using the above yellow, magenta, cyan and black developers.
Canon) in the order of development black, cyan, yellow,
It was modified so that images could be output in the order of magenta, and the image development was evaluated with the development contrast kept constant at 350V. Even if a durability test was performed on 20,000 full-color images, a clear tint was obtained. The image quality did not change significantly, background fog and the like were not observed, and the image density was as high as 1.4 to 1.5 for each color, and cleaning failure after endurance was not confirmed at all.

Further, a durability test of 30,000 sheets was conducted using only the black toner, but no toner fusion to the photosensitive member was observed,
No offset to the surface of the fixing roller was also confirmed, and a texture equivalent to that of an image of a black and white copier was obtained.

Example 6 Carbon black used as a colorant for black toner in Example 5 had an average particle size of 6
8 mμ, surface area 20 m ² / g, oil absorption 76 cc / 100
g and a pH value of 6.0, the same evaluation was conducted except that the binder resin used for the black toner was polyester resin B. As a result, a stable high image density was obtained and a full color image of 20,000 was obtained. The durability evaluation of 30,000 sheets was performed on one sheet and a black image, but neither offset nor cleaning failure was observed.

Example 7 The same evaluation was conducted except that the binder resin used for the black toner was polyester resin C. No offset or cleaning defects were observed, and a full-color image with high gloss and a black and white image were obtained. A black image having a gloss equivalent to that of a copying machine was obtained.

(Comparative Example 4) The same evaluation as in Example 5 was carried out except that images were developed in the order of magenta, cyan, yellow, and black. No defective cleaning or offset was observed even after the test, but in the case of a full-color image, the color mixture is inadequate and the tint is impaired.
The translucency in P and the like was also poor, and the overall image quality was degraded.

(Comparative Example 5) In Example 5, yellow,
The same evaluation was performed except that the binder resin used for each of the magenta and cyan toners was the polyester resin D, but the color mixture was not sufficient in the full-color image due to insufficient melt fixing at the time of fixing, and the tint was disturbed. Then, offset occurred in the durability test of about 5,000 sheets.

(Comparative Example 6) In Example 6, the same evaluation as in Example 5 was carried out except that the toner was formed except for titanium oxide as the fluidity improver used in the color toner and the black toner. Humid environment (30 ° C / 80% R
In H), fog occurred on the white background.

[0166]

The present invention has a stable fixing property in both black-and-white copying and color copying, and particularly in color copying.
It is possible to obtain an image with higher texture and gloss without impairing the surface smoothness. In particular, in the first invention, it is possible to improve the image characteristics in the combined system of non-magnetic and magnetic toner.

[Brief description of drawings]

FIG. 1 is a diagram showing gloss of a monochrome image and a full-color image.

FIG. 2 is a diagram showing a method for measuring a glass transition point.

FIG. 3 is a diagram showing gloss of a monochrome image and a full-color image.

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Claims (9)

[Claims] 1. A full-color toner for forming a color image using at least one selected from yellow toner, magenta toner, and cyan toner together with black toner as appropriate, wherein the yellow toner, magenta toner, and cyan toner Is a non-magnetic toner obtained by externally adding an external additive to colored resin particles formed by mixing and dispersing a colorant in a binder resin, and the binder resin is a diol component 45 selected from a bisphenol derivative or a substitution product. ˜55 mol% and a carboxylic acid component 55 to 45 mol% selected from dicarboxylic acid, an acid anhydride thereof or a lower alkyl ester thereof are polycondensed, and the hydroxyl value of the polyester resin is 50 or less, Weight average molecular weight (Mw) is 6,000
100,000, number average molecular weight (Mn) of 1,500
˜50,000, Mw / Mn is 4 to 6, and the black toner is a magnetic resin obtained by mixing and dispersing magnetic iron oxide powder containing 25 to 30% by weight of FeO and a release agent in a binder resin. A magnetic toner in which an external additive is externally added to particles, wherein the binder resin is an aromatic dicarboxylic acid component 25 to 25 selected from isophthalic acid, terephthalic acid, and derivatives thereof.
35 mol%, an aromatic tricarboxylic acid component selected from trimellitic acid and its derivative 2 to 4 mol%, a dicarboxylic acid component selected from dodecenylsuccinic acid, octylsuccinic acid and its anhydride, 12 to 18 mol%, and propoxy. Containing a polyester resin produced from a monomer composition comprising 45 to 60 mol% of an etherified and / or ethoxylated etherified diphenol component, wherein the polyester resin has a hydroxyl value of 10 to 20 and a weight average molecular weight (Mw). Is 13,000 to 20,000, number average molecular weight (Mn) is 5,000 to 8,000, and Mw / Mn is 2
A full-color toner having a value of 3.5. 2. The mold release agent has a melting start temperature of 40 ° C. or higher and a temperature of at least 2 at 50 to 250 ° C. as measured by DSC.
A releasing agent obtained by mixing one kind having two or more melting points or two kinds or more having different melting points in the range,
The full-color toner according to claim 1, wherein the content is 0.1 to 20 parts by weight per 100 parts by weight of the binder resin. 3. A yellow toner, a magenta toner, and a cyan toner as an external additive, having a weight average diameter of 0.01 to 0.01.
The full-color toner according to claim 1 or 2, wherein 0.2 µm of titanium oxide fine particles are externally added to a black toner as a fluidity improving agent, and silica fine powder having a weight average diameter of 0.001 to 2 µm is externally added. 4. A full-color toner that forms a color image by selectively using at least one selected from yellow toner, magenta toner, cyan toner, and black toner, wherein the yellow toner, magenta toner, and cyan toner The binder resin used for is a diol component 45 to 55 mol% selected from a bisphenol derivative or a substitution product,
55-45 mol of a carboxylic acid component selected from dicarboxylic acid, its acid anhydride or its lower alkyl ester
% Of the polyester resin having a hydroxyl value of 50 or less, a weight average molecular weight (Mw) of 6,000 to 100,000, and a number average molecular weight (Mn) of 1,500 to 50. 1,000, Mw / Mn is 4
The binder resin used for the black toner is selected from 25 to 35 mol% of aromatic dicarboxylic acid component selected from isophthalic acid, terephthalic acid and its derivative, trimellitic acid and its derivative. Aromatic tricarboxylic acid component 2 to 4 mol%, dodecenyl succinic acid, octyl succinic acid, and dicarboxylic acid component 12 to 18 mol% selected from its anhydride, and propoxylated and / or ethoxylated etherified diphenol component 45 to 60m
containing a polyester resin produced from a monomer composition consisting of ol%, and having a hydroxyl value of 10
-20, weight average molecular weight (Mw) is 13,000-2
50,000, the number average molecular weight (Mn) is 5,000 to 8,
000, Mw / Mn is 2 to 3.5, a full-color toner. 5. A yellow toner, magenta toner, and cyan toner as an external additive, having a weight average diameter of 0.01 to 0.01.
The full-color toner according to claim 4, wherein 0.2 μm of titanium oxide fine particles are externally added. 6. A yellow toner, a magenta toner, and a full-color toner according to claim 1.
And at least one of the cyan toners is appropriately and selectively used together with the black toner to develop the electrostatic charge image on the electrostatic charge image carrier to form a toner image, and the toner image is sequentially transferred onto a transfer material. An image forming method comprising: 7. The image forming method according to claim 6, wherein a black toner is developed on the first layer on the transfer material to control the image formation. 8. An electrostatic charge image bearing member comprising the full-color toner according to claim 4 and at least one of yellow toner, magenta toner, cyan toner, and black toner, which is appropriately selected. An image forming method comprising developing a charge image to form a toner image, and sequentially transferring the toner image onto a transfer material to form an image. 9. The image forming method according to claim 8, wherein a black toner is developed on the first layer on the transfer material to control the image formation.