JPH0784405A - Toner - Google Patents

Abstract

PURPOSE:To provide the toner excellent in the stabilization of electrification under various environment and satisfacrory in fixing property on paper and resistance to offset. CONSTITUTION:The toner containing the binding resin consisting of the polyester resin consisting of 30mol.% terephthalic acid, 4mol.% trimellitic anhydride, 16mol.% octyl succinic acid and 50mol.% etherified diphenol and having a OH value of 17.2, a weight-average mol.wt. of 17,000, a number-average mol.wt. of 6000 and Mw/Mn of 2.8 and the titanium oxide whose surface is subjected to the hydrophobic treatment, and having 8mum weight-average diameter is produced.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to toner, and in particular,
The present invention relates to a color toner that has high color reproducibility and is excellent in offset resistance that is difficult to offset to a fixing roller.

[0002]

2. Description of the Related Art In recent years, the development from white-black copying machines to full-color copying machines has been rapidly progressing, and two-color color copying machines and digitized full-color copying machines have begun to be put on the market.

Color image formation by full-color electrophotography generally reproduces colors by using color toners of three primary colors of yellow, magenta, and cyan, or four colors of black in addition thereto.

In the general method, first, the light from the original is formed on the photoconductive layer through a color separation light transmitting filter having a complementary color relationship with the color of the toner. Then development,
The toner is held on the support through the transfer process. 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.

In the color electrophotographic method which requires development of a plurality of times and superposition of several kinds of toner layers of different colors on the same support as the fixing step, the fixing characteristics that color toners should have. Is an extremely important factor.

That is, the fixed color toner is required to suppress diffused reflection due to toner particles as much as possible and to have an appropriate gloss and gloss.

Further, a color toner having a wide color reproducibility and having transparency that does not hinder the toner layers of different color tones under the toner layer.

As a color toner that can satisfy these requirements,
The applicants of the present invention have disclosed Japanese Patent Application Laid-Open Nos. 50-82442 and 5
Japanese Patent Application Laid-Open No. 1-144625 and Japanese Patent Application Laid-Open No. 59-57256 disclose novel combinations of a binder resin for a color toner and a colorant.

The color toners described above have a considerable sharp melt property, and when combined with a silicone rubber roller capable of applying silicone oil, the toner shape changes to a state of almost complete melting at the time of fixing, which is preferable. Glossiness and color reproducibility are obtained.

These effects mean that the viscous term is more important than the elastic term in the viscoelastic characteristic of the binder resin as the fixing characteristic of the toner.

That is, upon heating, 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 fusion, 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 deterioration in 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,
Due to the smoothness and cleanliness of the roller surface, some releasability can be maintained. However, the image area is large like a color image, and the amount of toner held on a support such as plain paper is
When the number of color copies, which is much larger than that of black and white copy images, 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-58-1195.
No. 3, JP-A-58-14144, JP-A-SHO-60
As described in JP-A-123852, a method of adding low-molecular-weight polyethylene, polypropylene, wax, higher fatty acid or the like, 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-57-208559.
Japanese Patent Laid-Open Publication No. 2003-242242, a monomer component 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. A toner containing a polyester made of a non-linear copolymer obtained from the above as a binder has been proposed. However, such a technique is to use a polyester containing an etherified bisphenol monomer and a dicarboxylic acid monomer as a binder. Offset prevention in the toner by incorporating a polyester obtained as a binder by crosslinking with a large amount of a monomer component containing a polyhydric alcohol monomer having a valence of 3 or more and / or a polycarboxylic acid monomer having a valence of 3 or more It has high performance. However, such a toner has a slightly high softening point, and thus it is difficult to perform good low-temperature fixing, and when used for full-color copying, the high-temperature offset resistance is at a practically practical level. As described above, since the fixing property and the sharp melt property are difficult, the color mixing property and the color reproducibility by superimposing full-color toners using the polyester are not desired. Further, JP-A-57-109825, JP-A-62-78568, JP-A-62-78569, and the like, and JP-A-59-7960 by the present applicant.
JP-A-59-29256 and JP-A-59-29256 disclose that an etherified bisphenol monomer, a dicarboxylic acid monomer into which a long-chain aliphatic hydrocarbon is introduced, and other dicarboxylic acid monomers are trivalent or higher. A non-linear copolymer obtained from a monomer component containing a polyhydric alcohol monomer and / or a polyvalent carboxylic acid monomer having a valence of 3 or more, the side chain of which has 3 to 22 carbon atoms. Although a toner containing a polyester having a saturated or unsaturated aliphatic hydrocarbon group as a binder has been disclosed, the purpose of these polyester resins is mainly for high-speed copying toners. In contrast to the above-mentioned viscous polyester, the elasticity is strengthened and the high temperature offset to the roller is remarkably reduced. Then, at the time of fixing, the pressure and heating of the heat roller are increased as much as possible, and the toner is pressed in a semi-molten state between the fibers of the transfer paper to perform heat fixing under pressure, thereby achieving the object. .

Therefore, the toner layer necessary for color copying cannot be melted to form a continuous film and a smooth surface can hardly be obtained, and the fixed toner exists in a particle state on the transfer paper to obtain a color obtained. The image is dull and the saturation is poor. In the OHP image, the light is scattered and diffused on the surface of the toner particles, almost no light is transmitted, and it becomes practically unusable.

Further, the present applicants have proposed a new polyester resin which is excellent in high temperature offset resistance and is applicable to color copying in JP-A-2-73366 and JP-A-1-224767. The resin is superior to the conventional color toner resin, but the effect of preventing the offset to the fixing roller is at most about 20,000 copies repeatedly, and the effect of preventing the offset of the black and white toner is Considering that the number of sheets is 100,000 or more, and the printing durability and offset resistance are several hundred thousand sheets under the present circumstances, it is preferable to further improve the performance. Further, the polyester was studied with the fixability 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, JP-A-62-195676, JP-A-62-195678 and JP-A-62-1956.
Japanese Patent Publication No. 80 discloses polyester resins in which the ratio of the hydroxyl value to the acid value is specified, but these polyester resins are also intended for high-speed fixing,
According to the study by the present inventors, the color toner using the resin has not reached the point where sufficient color mixing property is obtained.

As a problem peculiar to color copying, at least 3
Color toners of different colors, preferably four colors, must be balanced in color balance, and it is meaningless to discuss fixing characteristics and color reproducibility of only one color.

In principle, if there are three primary colors of yellow, magenta, and cyan, it should be possible to reproduce almost all colors by the primary color mixing method.
Therefore, the full-color copying machines on the market at present have a structure in which color toners of three primary colors are overlapped and used. This should ideally be able to achieve all color tones in all density ranges, but in reality, there are still points to be improved such as spectral reflectance characteristics of toner, mixability at the time of overlapping and fixing toner, and decrease in saturation. have.

When a black color is obtained by superimposing three colors, a toner layer three times as much as that of a monochromatic color is formed on the transfer paper, and further it is difficult for the offset resistance.

On the other hand, in the case of a so-called two-component developing system in which the developer is composed of a toner and a carrier, the developer charges the toner to a required charge amount and charge polarity by friction with the carrier, so that electrostatic attraction is exerted. This is used to develop an electrostatic image. Therefore, in order to obtain a good visible image, it is necessary that the triboelectric chargeability of the toner, which is mainly determined by the relationship with the carrier, is good.

In order to solve the above problems, the search for carrier core agents and carrier coating agents and the optimization of the coating amount, or the examination of charge control agents and fluidity-imparting agents to be added to toners, and the binder serving as the base material, are conducted today. Many studies have been made to achieve excellent triboelectrification properties in all materials constituting a developer, including improvements in the above.

For example, as a technique of adding a charging auxiliary agent such as charging fine particles to a toner, Japanese Patent Publication No. 52-32256
JP-A-56-64352 and JP-A-56-64352 add resin fine powder having a polarity opposite to that of the toner, and JP-A-61-160760 adds a fluorine-containing compound to the developer.
A technique for obtaining a stable triboelectric charging property has been proposed, and many charging aids have been developed even today.

Further, various methods have been devised as a method of adding the charging auxiliary agent as described above. For example, a method of adhering the toner particles to the surface of the toner particles by an electrostatic force between the toner particles and the charging auxiliary agent, a Van der Waals force, or the like is common, and stirring, a mixer, or the like is used. However, in this method, it is not easy to uniformly disperse the additive on the surface of the toner particle, and the additive does not adhere to the toner particle and the additives become aggregates, so that the existence of the additive in a so-called free state is present. It is difficult to avoid. This tendency becomes more remarkable as the specific electric resistance of the charging aid increases and the particle size decreases. In such a case, the performance of the toner is affected. For example, the amount of triboelectricity becomes unstable, the image density is not constant, and the image has a lot of fog.

Alternatively, when continuous copying or the like is carried out, the content of the charging aid changes, and it is not possible to maintain the initial image quality.

As another addition method, there is a method in which a charging auxiliary agent is added in advance together with the binder resin and the colorant when the toner is manufactured. However, it is not easy to make the charge control agent uniform, and it is the toner near the surface of the toner particles that substantially contributes to the chargeability, and the charge auxiliary agent and charge control agent present inside the particles have the chargeability Therefore, it is not easy to control the addition amount of the charging aid and the dispersion amount on the surface. Further, even in the toner obtained by such a method, the triboelectric charge amount of the toner is unstable and it is not possible to easily obtain a toner that satisfies the developer characteristics as described above. The reality is that the quality is not sufficiently satisfactory.

Further, in recent years, demands for high definition and high image quality of copying machines have been increasing in the market, and in this technical field, an attempt has been made to achieve high image quality color by making toner particle size fine. However, when the particle size becomes finer, the surface area per unit weight increases, and the amount of electrification of the toner tends to increase, and there is a concern that the image density is low and the durability is deteriorated. In addition, since the amount of electrification of the toner is large, the adhesion between the toners is strong, the fluidity is lowered, and problems occur in stability of toner replenishment and tribo application to the replenishment toner.

Further, since the color toner does not contain a magnetic substance or a conductive substance such as carbon black, there is no portion for leaking charge, and the amount of charge generally tends to be large. This tendency is more remarkable when a polyester binder having high charging performance is used.

Toners made of polyester resins are generally susceptible to temperature and humidity, and problems such as excessive charge amount under low humidity and insufficient charge amount under high humidity occur, and a stable charge amount is obtained even in a wide range of environments. There is an urgent need to develop color toners that it has.

One of the means for solving these problems is to add various chemical substances to the toner.

In particular, for the purpose of improving various image characteristics such as resolution, density uniformity, and fog, various fine powders are widely added to improve the chargeability and fluidity of the toner. Has been done.

Titanium oxide fine particles are mentioned as one of the fine powders generally used as the fine powders added for the improvement of various properties of the toner, and the one whose surface is hydrophobized is more preferably used.

As an example of toner containing hydrophobized titanium oxide, a toner containing titanium oxide treated with alkyltrialkoxysilane has been proposed in JP-A-59-52255. As a result, although various electrophotographic characteristics have been improved, the surface activity of titanium oxide is originally small and coalesced particles are generated at the treatment stage, and the hydrophobicity is not uniform or insufficient. It was not satisfactory when applied to toner.

[0036]

The object of the present invention is to exhibit good fixing property and color mixing property in electrophotographic technology, and to have stable triboelectric charging property which is hardly influenced by environment such as temperature and humidity. It has a high gloss that significantly enhances the quality, does not cause carrier spent even after repeated copying, has excellent durability, sufficiently prevents high temperature offset, has a wide fixing temperature range, and is resistant to offset even after repeated fixing paper passes. That is, it provides a toner having clear image characteristics without fog and excellent in durability stability.

[0037]

Means and Actions for Solving the Problems
(A) 25 to 35 mol% of divalent aromatic acid component (a) selected from isophthalic acid, terephthalic acid and its derivative, and (b) trimellitic acid and its derivative 3 Valent aromatic acid component (b) in an amount of 2 to 4 mol% of the total amount of monomers, (c) dodecenyl succinic acid,
The divalent acid component (c) at least selected from octyl succinic acid and its anhydride is added to the total monomer amount of 12 to 18 mo.
1%, (d) propoxylated and / or ethoxylated etherified diphenol component (d) is 4% of the total monomer amount.
Containing a polyester resin produced from a monomer composition containing at least 5 to 60 mol%, the hydroxyl value of the polyester resin is 10 to 20, the weight average molecular weight is 13,000 to 20,000, The number average molecular weight is 5,000 to 8,000, and the weight average molecular weight (M
w) / number average molecular weight (Mn) ratio is from 2 to 3.5,
The present invention also relates to a toner containing titanium oxide fine particles that have been subjected to a specific surface treatment.

In the color toner of the present invention, it can be said that the polyester resin of the present invention has, so to speak, a transitional character which combines the properties of both the linear polyester resin and the non-linear crosslinked polyester resin. It is considered that, as a result, good color mixing and color reproducibility were obtained as the color toner, and offset resistance to the fixing roller was obtained.

That is, the reason why the preferred characteristics are obtained in the present invention is presumed as follows.

(I) The trivalent aromatic acid component (b) such as trimellitic acid, which is a cross-linking monomer component, is converted into 20 molecules of one molecule of a divalent acid component and one molecule of a divalent alcohol component.
˜30 units, at most one molecule is regularly introduced into the chain of the linear condensate, and weak crosslinks are formed. 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.

(Ii) By extremely limiting its composition and amount of divalent acid component having a soft segment,
A full-color image with good color mixture and color reproducibility is obtained, and
It is designed so that the offset resistance is not adversely affected. In the weak cross-linking condensate of the feature (i), the amount of the cross-linking acid component and the amount of the acid component are naturally determined so as to keep a balance, and when too large, an abnormal sharp melt property is generated,
On the other hand, if the amount is too small, the glossiness and saturation of the color image are reduced.

In the present invention, while the trivalent carboxylic acid (b) is used as an essential component, the molecular weight distribution is narrower than that of a usual cross-linking binder resin (Mw / Mn = 2 to 3.5,
The above effect can be achieved by preferably 2.0 to 3.0).

(Iii) The other divalent acid component is the aromatic acid component (a) having a valency such as isophthalic acid and terephthalic acid, and a composition having elasticity without decreasing the viscosity of the polymer is selected as much as possible. ing. 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.

(Iv) The production conditions of the polyester resin of the present invention were changed from the conventional conditions so that the molecular weight distribution of the resin was as high as possible.
Especially, it is adjusted so that the distribution is sharp and narrow. 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 its molecular main chain 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, the low molecular weight condensate quickly melts, and exhibits a behavior such as fixing and color mixing, In addition, the phenomenon that the polymer condensate is almost insoluble occurs.

On the other hand, when a high temperature such that the polymer is melted 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, especially in the color toner, in order to have a relatively sharp melt property and to enhance the intermolecular aggregation of the polyester resin constituting the toner, the ratio of the weight average molecular weight to the number average molecular weight is used. Should be as small as possible. This is a more important attribute than discussed with black and white toner.

(V) In the characteristic (iv), 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. This manufacturing condition 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 composition of the polyester resin of the present invention and the production conditions. However, the conditions (i) to (v) must be satisfied in order to combine the fixing property and the charging property that satisfy the color mixing property, color reproducibility and offset resistance of the color toner.

Although the monomer composition and the like of the present invention can be considered to be similar to those of the prior art at first glance, the true aim of the present invention and the achievement point of the achieved technology are achieved by the conventional polyester resin and color toner. I didn't get it.

Therefore, in the present invention, the monomer component,
The composition ratio and various physical properties are extremely difficult to achieve the object of the present invention within a range other than those disclosed by the present invention.

First, the monomers constituting the polyester resin used in the present invention will be described.

(A) The divalent aromatic acid component selected from isophthalic acid, terephthalic acid and its derivatives is not particularly limited, but in addition to isophthalic acid and terephthalic acid, derivatives such as acid anhydrides and esters are available. Can be mentioned. Its content is 25 to 35 mol%, preferably 28 to 35
It is mol%. When the content of the component (a) is less than 25 mol%, the viscous behavior is increased and offset is likely to occur, which is not preferable. Further, if it exceeds 35 mol%, the elastic behavior is increased and the fixing property is deteriorated, which is not preferable.

(B) The trivalent aromatic acid component selected from trimellitic acid and its derivative is not particularly limited, but in addition to trimellitic acid, benzene-tricarboxylic acid ester, trimellitic anhydride, etc. Examples include derivatives. Its content is 2 to 4 mol%, preferably 2.5 to 4.0 mol%. When the content of the component (b) is less than 2 mol%, the crosslinking effect is insufficient and the offset resistance is lowered, which is not preferable. On the other hand, if it exceeds 4 mol%, the mobility of the polymer chain is hindered by cross-linking and the fixing property is lowered, which is not preferable. (C) The content of at least a divalent acid component selected from dodecenyl succinic acid, octyl succinic acid and its anhydride is 12 to 18 mol%, preferably 12 to 17 mo.
1%. When the content of the component (c) is less than 12 mol%, the glossiness and saturation of the image are impaired, which is not preferable. If it exceeds 18 mol%, the sharp-melting property becomes high,
Offset is likely to occur, which is not preferable. Preferred as (d) propoxylated and / or ethoxylated etherified diphenol components are ethoxylated or propoxylated etherified bisphenols,
It has 2 to 3 mol of oxyethylene or oxypropylene per mol of bisphenol.

For example, polyoxypropylene (2.2)
-2,2-bis (4-hydroxyphenyl) propane,
It is polyoxyethylene (2) -2,2-bis (4-hydroxyphenyl) propane. The content of the component (d) is 45 to 60 mol%, preferably 45 to 55 mo.
1%. When the content of the component (d) is less than 45 mol% or more than 60 mol%, the acid value or the hydroxyl value becomes high and the charging characteristics at high temperature deteriorate, which is not preferable.

The hydroxyl value of the polyester resin used in the present invention is 10 to 20, preferably 12 to 20. If the hydroxyl value is less than 10, the charge amount at low temperature tends to increase, which is not preferable. On the other hand, if it exceeds 20, the charging property at high temperature tends to deteriorate, which is not preferable.

The weight average molecular weight (Mw) is 13,0.
00-20,000, preferably 15,000-20,
000, number average molecular weight (Mn) is 5,000 to 8,000
It is 0, preferably 6,000 to 8,000. When the molecular weight is less than the lower limit, sufficient offset resistance cannot be obtained, which is not preferable. Further, if it exceeds the upper limit, the fixing property is deteriorated, which is not preferable.

Further, Mw / Mn is 2 to 3.5, preferably 2 to 3. When Mw / Mn is less than 2, both the low molecular weight component and the high molecular weight component are small and the balance between fixability and offset resistance is poor, which is not preferable. On the other hand, when it exceeds 3.5, the low molecular weight component particularly increases, and the offset resistance and blocking resistance are deteriorated, which is not preferable.

The production method for obtaining the polyester resin of the present invention is, for example, as follows.

First, a linear condensate is formed, and in the process, the molecular weight is adjusted so that the target acid value and hydroxyl value are 1.5 to 3 times, and the molecular weight is made slower than before so that the molecular weight becomes uniform. In order to allow the condensation reaction to proceed gradually, for example, the reaction is carried out at a lower temperature for a longer time than before, or the esterifying agent is decreased, or an esterifying agent having low reactivity is used, or a combination of these methods is used. The reaction is controlled by Then, under the conditions, a crosslinking acid component and, if necessary, an esterifying agent are further added to react with each other to form a three-dimensional condensate. The polyester resin of the present invention is obtained by further raising the temperature, allowing the reaction to proceed slowly and for a long time so that the molecular weight distribution becomes uniform, and promoting the crosslinking reaction, and ending the reaction when the hydroxyl value falls to a target value.

Furthermore, by combining the toner made of this polyester resin with titanium oxide fine particles which have been subjected to a specific surface treatment, the environmental stability of the charge amount is remarkably improved, the image quality is further improved, and the performance as a toner is improved. It became clear that it could be fully withdrawn.

Generally, as a method for producing titanium oxide fine particles, there are a dry method produced by oxidizing titanium tetrachloride or alkoxytitanium in a gas phase and a wet method produced by hydrolyzing titanium tetrachloride in an aqueous solution.

In the dry method using titanium tetrachloride, toxic chlorine gas is generated during the reaction, and a large-scale manufacturing apparatus and a complicated manufacturing process are required to recover the chlorine gas, and temperature control at high temperature is required. It has the difficulty of being difficult. Further, when alkoxytitanium is used, the raw material is very expensive and the temperature control is stricter, which is disadvantageous in cost.

On the other hand, in the wet method, no toxic by-product is generated even if titanium tetrachloride or the like is used. Therefore, the wet method using titanium tetrachloride as a raw material is safe, the manufacturing process is simple, and the material cost is low. In terms of However, when the wet titanium oxide thus obtained is taken out of the aqueous system as it is, coalesced particles are generated due to secondary agglomeration and the like, and it cannot be obtained as a uniform fine powder after drying. I can't pull out enough.

The inventors of the present invention have conducted extensive studies on stabilization of the chargeability of the toner. As a result, the surface of the produced titanium oxide fine particles can be subjected to a hydrophobic treatment as it is in an aqueous system so that a uniform hydrophobic treatment can be performed. It was found that the above-mentioned toner containing titanium oxide has extremely excellent characteristics in terms of stabilization of charging and imparting of fluidity.

It is more preferable to use a silicon compound as the surface treatment agent because a particularly high hydrophobicity can be obtained. When a silicon compound is used as a treatment agent for the titanium oxide fine particles used in the present invention, silicon oil, silicon varnish, high boiling point silane compound, silane coupling agent, or the like can be used alone or in combination. Further, the treatment amount is 0.1 with respect to 100 parts by weight of titanium oxide.
1 to 40 parts by weight, more preferably 1 to 30 parts by weight, the degree of hydrophobicity is 40 to 98%, preferably 60.
It should be -80%.

That is, if the degree of hydrophobicity is less than 40%, the amount of charge is greatly reduced by leaving it in a high humidity for a long period of time, and a mechanism for promoting charge on the hardware side is required, which leads to complication of the apparatus and hydrophobicity. If the degree exceeds 98%, it becomes difficult to control the charge of titanium oxide itself, and as a result, the toner is charged up in low humidity.

The particle size is 0.0 from the viewpoint of imparting fluidity.
1 to 0.3 μ is preferable. When the particle size is larger than 0.3 μm, toner charging becomes non-uniform due to poor fluidity, resulting in toner scattering and fog. On the other hand, if it is smaller than 0.01 μm, the toner is likely to be embedded on the toner surface and the toner is deteriorated quickly, and the durability is deteriorated. This tendency is more remarkable in the sharp melt color toner used in the present invention.

Further, one feature of the present invention is that the treated titanium oxide has a light transmittance of 40% or more at a light length of 400 nm.

That is, when the titanium oxide of the present invention is used as a full-color toner, if the transparency to visible light is poor, the projected image of the OHP will be shaded and a clear toner will not be obtained.

In the present invention, the method for treating titanium oxide is not particularly limited, but it is effective to perform surface treatment with a treating agent while mechanically dispersing titanium oxide in an aqueous system so as to have a primary particle size. is there. Moreover, you may reprocess with an organic solvent after that.

When reprocessing in an organic solvent, a treating agent may be further added, and the treating agent to be added may be different from the treating agent used for the treatment in the aqueous system.

The titanium oxide of the present invention has a weight average particle diameter of 4 to 1
It is suitable for the toner of the present invention having a small particle size of 0 μm. When the particle size of the toner is reduced, the surface area per weight is increased, and excessive charging due to rubbing tends to occur. On the other hand, the effect of titanium oxide fine particles that can control charge and impart fluidity is great.

When the toner of the present invention is used as a one-component toner by incorporating magnetic powder, a substance that is magnetized by being placed in a magnetic field is used as the magnetic powder. Iron, cobalt, nickel There are powders of ferromagnetic metals such as and alloys and compounds such as magnetite, hematite and ferrite. The content of the magnetic powder is 15 to 70% by weight based on the weight of the toner.

Carbon black, titanium white, and any other pigments and / or dyes can be used as the colorant regardless of whether the toner is a one-component toner or a two-component toner.

For example, when the toner of the present invention is used as a magnetic color toner, the dye may be 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. Mordant Red 30, C.I. I. Direct Blue 1, C.I. 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. Mordant Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. There are Basic Green 6 etc. Pigments include yellow lead, cadmium yellow, mineral fast yellow, navel yellow, naphthol yellow S, Hansa yellow G, permanent yellow NCG, tartrazine lake, red lead yellow lead, molybdenum orange, permanent orange GT.
R, Pyrazolone Orange, Benzidine Orange G, Cadmium Red, Permanent Red 4R, Watching Red Calcium Salt, Eosin Lake, Brilliant Carmine 3B, Manganese Purple, Fast Violet B, Methyl Violet Lake, Navy Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue rake, phthalocyanine blue, fast sky blue, indanthrene blue BC, chrome green, chrome oxide, pigment green B, malachite green rake, final yellow green G and the like.

When the toner of the present invention is used as a full-color toner, the following may be mentioned.

Examples of magenta color pigments include C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9,
10, 11, 12, 13, 14, 15, 16, 17, 1
8, 19, 21, 22, 23, 30, 31, 32, 3
7, 38, 39, 40, 41, 48, 49, 50, 5
1, 52, 53, 54, 55, 57, 58, 60, 6
3,64,68,81,83,87,88,89,9
0,112,114,122,123,163,20
2,206,207,209, C.I. I. Pigment violet 19, C.I. I. Bat red 1, 2, 10, 1
3, 15, 23, 29, 35 and the like.

The pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment in combination.

As the magenta dye, C.I. I. Solvent Red 1,3,8,23,24,25,27,3
0,49,81,82,83,84,100,109,
121; C.I. I. Disperse Red 9; C.I. I. Solvent Violet 8, 13, 14, 21, 27, C.I.
I. Oil soluble dyes such as Disperse Violet 1, C.I.
I. Basic Red 1, 2, 9, 12, 13, 14,
15, 17, 18, 22, 23, 24, 27, 29, 3
2,34,35,36,37,38,39,40; C.I.
I. Basic Violet 1,3,7,10,14,
Basic dyes such as 15, 21, 25, 26, 27 and 28 are mentioned.

As the color pigment for cyan, C.I. I. Pigment Blue 2, 3, 15, 16, 17; C.I. I. Bat Blue 6; C.I. I. Acid Blue 45 or a copper phthalocyanine pigment having a phthalocyanine skeleton having a structure represented by the formula (1) substituted with 1 to 5 phthalimidomethyl groups.

[0081]

[Chemical 1]

As the color pigment for yellow, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10,
11, 12, 13, 14, 15, 16, 17, 23, 6
5, 73, 83; C.I. I. Bat yellow 1,3,20
And so on.

The amount of the colorant used is 0.1 to 60 parts by weight, preferably 0.5 to 50 parts by weight, based on 100 parts by weight of the binder resin.
Parts by weight.

Further, the toner according to the present invention has a negative chargeability,
Although the positive chargeability is not limited, a charge control agent may be added for the purpose of stabilizing the negative charge characteristic when producing a negatively chargeable toner. Examples of the negative charge control agent include the aforementioned azo metal complexes, metal complexes of alkyl-substituted salicylic acid, phenolic resins, polymethacrylic acid, styrene and acrylic acid, methacrylic acid copolymers and maleic acid-added styrene-butadiene copolymers. Examples of the resin include a resin containing a carboxyl group as described above, and a resin having a carboxyl group or an OH group at the polymer terminal after condensation polymerization such as polyester.

When a positively chargeable toner is prepared, nigrosine, a triphenylmethane compound, a rhodamine dye, polyvinyl pyridine or the like may be used as a charge control agent having a positive chargeability. Further, in the case of producing a color toner, 0.1 to 40 mol%, preferably 1 to 40 mol%, of an aminocarboxylic acid-containing ester such as dimethylaminomethyl methacrylate, which exhibits a positive charging property, as a monomer.
A binder resin containing 30 mol% may be used, or a colorless or pale color positive charge control agent that does not affect the color tone of the toner may be used. Examples of the positive charge control agent include quaternary ammonium salts represented by structural formulas (A) and (B).

[0086]

[Chemical 2]

[0087]

[Chemical 3]

Among the quaternary ammonium salts represented by the structural formulas (A) and (B), the positive charge control agents represented by the structural formulas (A) -1, -2 and the structural formula (B) -1 are used. Are preferable because they show good chargeability with little environmental dependence.

[0089]

[Chemical 4]

[0090]

[Chemical 5]

[0091]

[Chemical 6]

When an aminocarboxylic acid-containing ester such as dimethylaminomethyl methacrylate, which exhibits positive charging characteristics, is used as the resin component of the binder resin in the positive charging toner, a positive charge control agent or negative charge control is used. Use agents as needed.

In the case of the negatively chargeable toner, the negative charge control agent is used in an amount of 0.1 to 20 relative to 100 parts by weight of the binder resin.
Parts by weight, preferably 0.5 to 15 parts by weight.

In the case where the aminocarboxylic acid-containing ester such as dimethylaminomethyl methacrylate showing a positive charging characteristic is not used as the resin component in the positively chargeable toner, the positive charge control agent is added to 100 parts by weight of the binder resin. 0.1 to 15
It is desirable to use parts by weight, preferably 0.5 to 10 parts by weight. Further, when the aminocarboxylic acid-containing ester is used, a positive charge control agent and / or a negative charge control agent may be added to 100 parts by weight of the binder resin for the purpose of providing good chargeability with little environmental dependence. It is desirable to use 0 to 10 parts by weight, preferably 0 to 8 parts by weight.

Further, in the toner of the present invention, a fluidity improver other than titanium oxide may be used in combination for the purpose of further improving the fluidity of the toner.

As such a flow improver, any flow improver can be used as long as the flowability can be increased by adding it to the colorant-containing resin particles as compared with before and after addition.

For example, fluorine resin powder, that is, fine powder of vinylidene fluoride, fine powder of polytetrafluoroethylene, or the like; or fatty acid metal salt, that is, zinc stearate,
Calcium stearate, lead stearate, etc .; or metal oxides, that is, zinc oxide powder, etc .; or fine powder silica, that is, wet process silica, dry process silica, silane coupling agents, titanium coupling agents, silicone oils to these metal oxides. There are surface-treated metal oxides, etc.

When the toner of the present invention is used as a two-component developer using a carrier, an electrically insulating resin is used as a coating resin for the surface of the carrier, which is appropriately selected depending on the toner material and the carrier core material. . In the present invention, at least one monomer selected from at least acrylic acid (or its ester) monomer and methacrylic acid (or its ester) monomer in order to improve the adhesion to the surface of the carrier core material. It is necessary to contain.
In particular, when polyester resin particles having a high negative chargeability are used as the toner material, it is preferable to use a copolymer with a styrene-based monomer for the purpose of stabilizing the charge. Is preferably 5 to 70% by weight.

As the monomer for the resin for coating the carrier core material which can be used in the present invention, as the styrene-based monomer,
For example, styrene monomer, chlorostyrene monomer, α
-Methylstyrene monomer, styrene-chlorostyrene monomer and the like, and examples of acrylic monomers include acrylic acid ester monomers (methyl acrylate monomer, ethyl acrylate monomer, butyl acrylate monomer, octyl acrylate monomer, phenyl acrylate monomer). , Acrylic acid 2 ethylhexyl monomer) and the like, and methacrylic acid ester monomers (methyl methacrylate monomer, ethyl methacrylate monomer, butyl methacrylate monomer, phenyl methacrylate monomer) and the like.

The carrier core material (magnetic particles) used in the present invention includes, for example, surface-oxidized or unoxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, chromium, rare earths, and alloys or oxides thereof. Things can be used.
Moreover, there is no particular limitation in the manufacturing method.

The measuring method in the present invention will be described below.

(1) Measurement of weight average molecular weight (Mw) and number average molecular weight (Mn): In the present invention, HLC-802.
Mw and Mn are measured using A type (made by Toyo Soda Co., Ltd.). Column is TSKgel GMH manufactured by Toyo Soda Kogyo Co., Ltd.
6x2 is used and THF is used as the solvent. The detector is
Using RI (refractive index), the sample is injected at a concentration of 0.5% with an injection volume of 200 μl.

The molecular weight of the sample is calculated from the relationship between the logarithmic value and the count number of the calibration curve prepared by using several kinds of monodisperse polystyrene standard samples for the molecular weight distribution of the sample.

As a standard polystyrene sample for preparing a calibration curve, for example, a molecular weight of 6 × 10 ² , 2.1 manufactured by Pressure Chemical Company or Toyo Soda Industry Co., Ltd.
× 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 1
0 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10
^It is suitable to use ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ and use at least about 10 standard polystyrene samples.

(2) Measurement of hydroxyl value: JIS K007
The measurement is carried out by the following method according to the method shown in.

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 top 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 with an N / 2KOH-THF solution as an indicator using an alcohol solution of phenolphthalein as a indicator using a 50 ml (scale amount 0.1 ml) burette. 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.

[0109]

[Equation 1]

Here A: N / 2KOH required for this test
-Ml number of THF solution B: ml number of N / 2KOH-THF solution required for blank test f: titer of N / 2KOH-THF solution S: sampled amount (g) C: acid number or alkali number. However, the acid value is positive and the alkali value is negative. The average of the two measurements is used.

(3) Method of measuring transmittance: 1. Sample 0.10g Alkyd resin 13.20 * 1 Melamine resin 3.30 * 2 Thinner 3.50 * 3 Glass media 50.00 * 1 Dainippon Ink Beckosol 1323-60-E
L * 2 Super Nippon Beckamine J-820 manufactured by Dainippon Ink
60 * 3 Amylak thinner made by Kansai Paint

The above mixture was sampled in a glass bottle with a 150 cc lid and dispersed for 1 hour using a paint conditioner manufactured by Red Devil. 2. After the dispersion is completed, the PET film is coated with a 2 mil doctor blade. 3.2. Is heated at 120 ° C. for 10 minutes to perform baking. 4.3. The sheet is measured with a U-BEST 50 manufactured by JASCO Corporation in the range of 320 to 800 nm to compare the transmittance.

(4) 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 Co.).

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

This was placed in an aluminum pan, and an empty aluminum pan was used as a reference, and the measurement temperature range was 30 ° C to 2 ° C.
The measurement is performed at a temperature rising rate of 10 ° C./min between 00 ° C. and normal temperature and normal humidity.

During this temperature raising process, an endothermic peak of the main peak in the temperature range of 40 to 100 ° C. is obtained.

At this time, the intersection of the line at the midpoint of the baseline before and after the appearance of the endothermic peak and the differential heat curve is taken as the glass transition temperature Tg in the present invention.

[0118]

The present invention will be described in detail with reference to the following examples.

Production of Polyester Resin An example of production of polyester resin is shown below.

Table 1 shows the respective compositions and molecular weights.

(Production Example 1 of polyester resin) 2 mol of terephthalic acid, 1.09 mol of octyl succinic acid, polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, hereinafter referred to as P.I. O. Modified bisphenol A, 3.4 mol, dibutyltin oxide 0.01
g was placed in a glass 2-liter four-necked flask, and a thermometer, a stir bar, a condenser, and a nitrogen introducing tube were attached and placed in a mantle heater. Next, after replacing the inside of the flask with nitrogen gas, the temperature is gradually raised with stirring to 170 ° C.
The reaction was carried out 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 is 6
It was 3.

Then, trimellitic anhydride 0.3mo
1 and 0.08 g of dibutyltin oxide were added, and 190
The reaction was allowed to proceed for 3 hours at 0 ° C., the temperature was further raised to 200 ° C., the reaction was allowed to proceed for 5 hours, and the reaction was completed to obtain the polyester resin (A) of the present invention.

At that time, the hydroxyl value was 17.2, the glass transition temperature was 64 ° C., the weight average molecular weight was 17,000, the number average molecular weight was 6000, and the ratio was about 2.8.
Met.

(Production Example 2 of polyester resin) 2.0 mol of isophthalic acid, 1.2 mol of dodecenylsuccinic acid,
P. O. Production Example of Modified Bisphenol A 3.4 mol-
In the same manner as in 1, the reaction was carried out in a nitrogen atmosphere. Then
0.15 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.
A polyester resin (B) of the present invention was obtained.

The hydroxyl value of this resin was 16.1, glass transition temperature 66 ° C., weight average molecular weight (Mw) 16000, number average molecular weight (Mn) 6100, and Mw / Mn was about 2.6.

(Production Example 3 of polyester resin) terephthalic acid 3.5 mol dodecenylsuccinic acid 1.2 mol trimellitic acid 0.3 mol P. O. Hydroxyl value of 16.8, Tg in the same manner as in Production Example 1 using 0.05 g of modified bisphenol A 5 mol cibutyltin oxide.
70 ° C., Mw 19000, Mn 8000, Mw / Mn =
2.1 polyester resin (C) was obtained.

Comparative Production Example 1 Terephthalic acid 2.0 mol Dodecenyl succinic acid 2.6 mol Trimellitic acid 0.4 mol P. O. Using modified bisphenol A 5 mol cibutyltin oxide 0.1 g, the hydroxyl value was 15.6 and Tg in the same manner as in Production Example 2.
59 ° C., Mw 18000, Mn 5200, Mw / Mn =
A polyester resin (D) of 3.5 was obtained.

Comparative Production Example 2 Terephthalic acid 3.8 mol Dodecenyl succinic acid 1.1 mol Trimellitic acid 0.1 mol P. O. Using 0.1 g of modified bisphenol A 5 mol cibutyltin oxide, a hydroxyl value of 15.4, T was obtained in the same manner as in Production Example 2.
g 55 ° C., Mw 13000, Mn 5000, Mw / Mn
= 2.6 of polyester (E) was obtained.

(Comparative Production Example 3) Terephthalic acid 2.5 mol Octyl succinic acid 2.0 mol Trimellitic acid 0.5 mol Ethylene glycol 1 mol P. O. Hydroxyl value of 17.1, T was obtained in the same manner as in Production Example 1 using 0.05 g of modified bisphenol A 4 mol cybutyltin oxide.
g 82 ° C, Mw 19000, Mn 7800, Mw / Mn
= 2.4 polyester resin (F) was obtained.

(Comparative Production Example 4) O. 5.0 mol of modified bisphenol A was placed in a four-necked flask, a stirrer, a condenser, a thermometer, and a gas introduction tube were set, and placed in a mantle heater. After purging the inside of the reaction vessel with nitrogen gas, the content was adjusted to 50 to 60 ° C., and then succinic acid (C ₁₆ H ₃₀ O ₄ ) 1 in which 3.5 mol of terephthalic acid and the alkenyl group of C ₁₂ were substituted was used. 0.1 mol, trimellitic acid 0.4 mol and dibutyltin oxide 0.05 g were added.

The mixture system was heated to 210 ° C. with stirring.
After about 5 hours while removing the water of reaction, the reaction product was cooled to room temperature to obtain polyester (G).

As the reaction conditions, all the monomer components were charged all at once, the reaction temperature was high, and the reaction time was short, so that the molecular weight distribution was broader than that of the present invention, and the average molecular weight was low. In connection with this, the hydroxyl value was as high as 31.

At this time, Mw is 12000 and Mn3100.
And Mw / Mn was 3.9.

[0134]

[Table 1]

Production of Titanium Oxide (Production Example 1 of Titanium Oxide) While mixing and stirring the hydrophilic titanium oxide fine particles produced in an aqueous system, 25 ° C. as a treating agent.
A dimethylpolysiloxane having a viscosity of 500 centistokes was dispersed in a water system to form an emulsion, and the mixture was added and mixed so that the particles would not be united so that they would be 5% of the titanium oxide fine particles in terms of solid content. Crushed, hydrophobicity 40%, average particle size 0.05μ, 400nm
To obtain titanium oxide fine particles I having a transmittance of 50%.

(Production Example 2 of Titanium Oxide) In Production Example 1, n-C ₄ H ₉ S was used instead of dimethylpolysiloxane.
i (OCH ₃ ) ₃ of titanium oxide fine particles in terms of solid content
Titanium oxide fine particles II having a hydrophobicity of 60%, an average particle size of 0.05 μm, and a transmittance of 55% at 400 nm were obtained by the same treatment except that 0% was used.

(Production Example 3 of Titanium Oxide) By the same treatment as in Production Example 1, except that the amount of dimethylpolysiloxane used was 0.1%, the degree of hydrophobicity was 0% and the average particle size was 0.
Titanium oxide fine particles III having a transmittance of 25% at 3μ and 400 nm were obtained.

[0138] The following production examples of producing the toner in the toner and Table 2.

(Toner Production Example 1) 100 parts by weight of polyester A 4.0 parts by weight of copper phthalocyanine pigment 4.0 parts by weight of 3,5-ditertiary butyl salicylate chromium complex 4.0 parts by weight were melt-kneaded by a roll mill, cooled, and then coarsely pulverized. Then, finely pulverized and classified to obtain colored resin particles (a). The colored resin particles (a) were mixed with 1.0% of titanium fine particles I by a Henschel mixer to obtain a toner 1 having a Tg of 62 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 2) The colored resin particles (a) in Toner Production Example 1 were mixed with 1.0% of titanium fine particles II by a Henschel mixer to obtain a toner 2 having Tg of 62 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 3) 100 parts by weight of polyester A 30 parts by weight of magnetic particles having an average particle size of 0.3 μm

[0142]

[Chemical 7] 1% of titanium fine particles II was added to the black magnetic fine powder obtained in the same manner as in Toner Production Example 1 to obtain Toner 3 having a Tg of 64 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 4) Polyester B 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butylsalicylic acid chromium complex 4.0 parts by weight As a raw material, the same method as in Toner Production Example 1 was used. The colored resin particles obtained in 1 were mixed with 1% of titanium fine particles II to obtain a toner 4 having a Tg of 66 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 5) Polyester C 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butylsalicylic acid chromium complex 4.0 parts by weight As a raw material, the same method as in Toner Production Example 1 was used. The colored resin particles obtained in 1 were mixed with 1% of titanium fine particles II to obtain a toner 5 having Tg of 70 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 6) 1% of titanium fine particles III was mixed with the colored resin particles (a) obtained in Production Example 1 to obtain a toner 6 having Tg of 62 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 7) Polyester D 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butylsalicylic acid chromium complex 4.0 parts by weight As a raw material, titanium fine particles II 1% was used, and a toner was prepared. Tg 58 ° C., weight average particle size 8 μm in the same manner as in Production Example 1.
m toner 8 was obtained.

(Toner Production Example 8) 100 parts by weight of polyester D 30 parts by weight of magnetic particles having an average particle size of 0.3 μm

[0148]

[Chemical 8] 1% of titanium fine particles II was added to the black magnetic fine powder obtained in the same manner as in Toner Production Example 3 to obtain Toner 9 having Tg of 58 ° C. and a weight average particle diameter of 8 μm.

(Toner Production Example 9) Polyester E 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butylsalicylic acid chromium complex 4.0 parts by weight As a raw material, titanium fine particles II 1% was used, and a toner was prepared. In the same manner as in Production Example 1, Tg 54 ° C, weight average particle diameter 8μ
m toner 10 was obtained.

(Toner Production Example 10) Polyester F 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butyl chromium salicylate chromium complex 4.0 parts by weight As a raw material, titanium fine particles II 1% was used, and a toner was prepared. A toner 11 having a Tg of 81 ° C. and a weight average particle diameter of 8 μm was obtained in the same manner as in Production Example 1.

(Toner Production Example 11) Polyester G 100 parts by weight Copper phthalocyanine pigment 4.0 parts by weight 3,5-ditertiary butylsalicylic acid chromium complex 4.0 parts by weight As a raw material, titanium fine particles II 1% was used, and a toner was prepared. A toner 12 having a Tg of 51 ° C. and a weight average particle diameter of 8 μm was obtained in the same manner as in Production Example 1.

[0152]

[Table 2]

(Example 1) Toner 2 obtained in Production Example 2 was mixed with 5 parts of a copolymer of 75% methyl methacrylate and 25% butyl acrylate (weight average molecular weight 200,000) to give a weight average particle diameter. 45μ, 35μ or less 4.2
%, 35-40 μ9.5%, 0.5 μ% of a Cu—Zn—Fe ferrite carrier having a particle size distribution of 74 μ or more and 0.2% or more is mixed to a total amount of 100 parts to obtain a developer. did.

Using this developer, a commercially available plain paper color copying machine (color laser copier 500, manufactured by Canon Inc.) was used to set the development contrast to 300 V, and 23 ° C./65%.
Images were drawn below. The image obtained is Macbeth RD9
Reflection density measurement was performed using an 18-inch SPI filter (the same applies to subsequent image density measurement methods). The image density was as high as 1.48 and was clear without any fog. Also, the OHP projection image was clear and had no dust. After that, 10,000 more copies were made, but the density fluctuation during that time was as small as 0.09, and the fog and sharpness were the same as in the initial stage. Under low temperature and low humidity (20 ℃ /
Even at 10% RH), when the development contrast was set to 300 V and image formation was performed, the image density was as high as 1.44, suggesting that the present invention was effective in controlling the charge amount under low humidity. ing.

Further, even under high temperature and high humidity (30 ° C./80%)
Similarly, when the development contrast was set to 300 V and image formation was performed, a good image was obtained although the image density was slightly high at 1.56 to 1.61.

23 ° C./60% RH, 20 ° C./10
%, 30 ° C./80%, the initial image after being left for 1 month in each environment showed no abnormality.

Rubbing Test on Paper In order to confirm the fixing property of the toner on the paper, the image was rubbed with a finger and the degree of peeling of the toner was observed. The results are shown in Table 3 together with the results of electrophotographic characteristics.

(Example 2) The same operation as in Example 1 was carried out except that Toner 1 was used instead of Toner 2 in Example 1, and the image density was 1.55 to 1.50% at 30 ° C / 80%. 6
Although it was slightly higher, it was at a level where there was no practical problem.
The evaluation results are shown in Table 3.

(Example 3) Using Toner 3, images were printed at 23 ° C / 65% under a Canon Electrophotographic Copier FC5. The image density obtained was as high as 1.49 to 1.54 from the initial stage to 1000 sheets and was clear without any fog.

Further, even at 20 ° C./10% below 1.4
1.41 even at 30 ° C / 80% of 3 to 1.47
The high density of ˜1.45 was maintained and the image quality was good. The evaluation results are shown in Table 3.

(Examples 4 and 5) The same experiment as in Example 1 was carried out except that Toners 4 and 5 were used in place of Toner 1 in Example 1, and the results were 30 ° C / 80% and 20 ° C / 1.
The image density was 1.47 to 1.57 and the image quality was good under any environment of 0%. Table 3 shows the evaluation results
Shown in.

(Comparative Example 1) The same operation as in Example 1 was carried out except that Toner 6 was used in place of Toner 1 in Example 1. As a result, the image density increased to 1.70 at 30 ° C / 80%. Fog and toner scattering were slightly recognized as compared with Example 1, but there was no problem on the actual image. Also, O
The sharpness of the HP projected image was slightly lowered. The evaluation results are shown in Table 3.

(Comparative Example 2) An experiment was conducted in the same manner as in Example 1 except that Toner 8 was used instead of Toner 1 in Example 1, and the image density was stable at 1.44 to 1.58 regardless of the environment. However, when the silicone oil-impregnated web was observed after printing 5000 sheets, stains due to the offset toner were found. Also, the sharpness of the OHP projected image was slightly lowered. The evaluation results are shown in Table 3.

Comparative Example 3 An experiment was conducted in the same manner as in Example 3 except that Toner 9 was used instead of Toner 3 in Example 3, and the image density was 1.39 in any environment.
However, when the fixing pad was observed 1000 times after the image was printed, the stain due to the offset toner was found. The evaluation results are shown in Table 3.

(Comparative Example 4) An experiment was conducted in the same manner as in Example 1 except that Toner 10 was used instead of Toner 1 in Example 1, but the image density was stable at 1.43 to 1.58. Staining due to offset toner was observed on the web after 5000 sheets of images were printed. The evaluation results are shown in Table 3.

Comparative Example 5 An experiment was conducted in the same manner as in Example 1 except that Toner 11 was used in place of Toner 1 in Example 1, but the image density was stable at 1.44 to 1.59. Staining due to offset toner was observed on the web after 5000 sheets of images were printed. Also, the sharpness of the OHP projected image was slightly lowered. The evaluation results are shown in Table 3.

Comparative Example 6 An experiment was conducted in the same manner as in Example 1 except that Toner 12 was used in place of Toner 1 in Example 1, and the image density was 1.78 under the conditions of 30 ° C./80%. It became higher, and fog and toner scattering were observed. The evaluation results are shown in Table 3.

[0168]

[Table 3]

[0169]

EFFECTS OF THE INVENTION According to the present invention, the toner made of the polyester resin having the above-mentioned constitution is externally added to the titanium oxide fine particles which have been subjected to the hydrophobizing treatment in the aqueous system, to stabilize the charge in various environments. It is possible to obtain a toner which is excellent in fixing property on paper and offset resistance.

Claims (3)

[Claims] 1. A toner comprising at least a binder resin and a colorant, wherein the binder resin is (a) isophthalic acid,
A divalent aromatic acid component (a) selected from terephthalic acid and its derivatives is used in an amount of 25 to 35 mol% of the total amount of monomers,
(B) Trivalent aromatic acid component (b) selected from trimellitic acid and its derivatives in an amount of 2 to 4 mol based on the total amount of monomers.
%, (C) a divalent acid component (c) selected from at least dodecenylsuccinic acid, octylsuccinic acid and their anhydrides.
From the monomer composition containing at least 12 to 18 mol% of the total amount of the monomer, and (d) at least 45 to 60 mol% of the propoxylated and / or ethoxylated etherified diphenol component (d) to the total amount of the monomer. The produced polyester resin is contained, the hydroxyl value of the polyester resin is 10 to 20, and the weight average molecular weight is 13,000 to 2
And the number average molecular weight is 5,000 to 8.0.
And a weight average molecular weight (Mw) / number average molecular weight (Mn) ratio of 2 to 3.5 and containing titanium oxide whose surface is hydrophobized. Toner of 10 μm. 2. The titanium oxide has an average particle size of 0.01 to
The toner according to claim 1, wherein the toner has a hydrophobicity of 0.3 μm, a hydrophobicity of 40 to 98%, and a light transmittance at 400 nm of 40% or more. 3. The titanium oxide is 0.1-4 in an aqueous system.
The toner according to claim 1, which is surface-treated with 0 part by weight of a silicon compound.