JPH08292604A - Yellow toner - Google Patents

Abstract

PURPOSE: To obtain a yellow image having excellent triboelectric property, high image density and high durability, and showing sharp hue, by incorporating a binder resin and a blend pigment prepared by blending specified two kinds of compds. CONSTITUTION: This yellow toner contains yellow toner particles containing at least a binder resin, a compd. No.1 expressed by formula I and a compd. No.2 expressed by formula II. Thereby, the triboelectric property of the yellow toner is stabilized. By blending the compd. No.1 having two chlorine atoms and the compd. No.2 having one chlorine atom, stable negative triboelectrification property can be obtd., and by using the combination of the compd. No.1 and the compd. No.2, deviation of hue toward blue or red which is caused when only the compd. No.1 or compd. No.2 is used can be suppressed but a sharp yellow color can be obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography, electrostatic recording,
The present invention relates to a yellow toner applied to a developer for developing an electrostatic charge image in electrostatic printing or the like.

[0002]

2. Description of the Related Art With the recent decrease in price of computer equipment for personal users, full-color image communication is becoming widespread in the visual information transmission mechanism from the visual world. Based on these needs, even in printers and copiers, which are one of the output means, full-colorization is rapidly advancing mainly in the low-end machine market, and color images become more familiar to general users. It's starting.

Generally, there are many methods such as a thermal transfer method, an ink ribbon method, and an ink jet method as such a full-color output device, but the majority are electrophotographic methods as a whole. Generally, the method uses a photoconductive substance to form an electrical latent image on a photoconductor by various means, then develops the latent image with a toner and, if necessary, a toner on a transfer material such as paper. After the image is transferred, it is fixed by heating, pressure, heating and pressing, solvent vapor or the like to obtain a color image. In the case of full color, the three primary colors of the color material are yellow, magenta,
Color reproduction is performed by using three color toners of cyan or four colors of black color added thereto. For example, 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 color toner is held on the support through the developing and transfer steps. Next, the above-mentioned steps are sequentially carried out a plurality of times, and while matching the registration, the color toners are superposed on the same support, and the final full-color image is obtained by fixing.

As the yellow toner, C.I. I. Pig
ment74, C.I. I. Pigment Yellow
A yellow toner containing 93 or the like as a yellow colorant is known, but a yellow toner excellent in triboelectrification characteristics, electrophotographic characteristics such as durability of a large number of sheets, good color tone, and excellent weather resistance is desired. Has been done.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a yellow toner which solves the above problems.

An object of the present invention is to provide a yellow toner having an excellent triboelectric charging property. A further object of the present invention is to provide a yellow toner capable of forming a toner image having a high image density, achieving high durability, and having a clear tint.

[0007]

The present invention includes at least a binder resin and a compound No. 1 represented by the following formula (1).
(1) and the compound No. represented by the following formula (2).
The present invention relates to a yellow toner having yellow toner particles containing (2).

[0008]

[Outside 4]

As a result of intensive investigations by the present inventors, as a yellow colorant used in a yellow toner, the above formula (1) is used.
Compound No. (1) and the compound No. represented by the above formula (2). By using (2), the triboelectric charging ability of the yellow toner can be stabilized.

Compound No. 2 having two chloro groups. (1)
And compound No. 1 having one chloro group. By blending and using (2), stable negative triboelectric charging ability can be obtained, and compound No. (1) and compound No. By using in combination with (2), compound No. (1) only or compound No. The effect of suppressing the hue deviation toward the blue direction or the red direction, which is seen when only (2) is used alone, can be obtained, and a clear yellow color can be obtained.

Compound No. (1) is a compound No. represented by the following formula (3). (3) is preferred, and / or compound No. (2) is compound No. represented by the following formula (4). It is preferably (4).

[0012]

[Outside 5]

Compound No. (1) and compound No. (2)
The mixing ratio by weight is preferably 1:99 to 99: 1, more preferably 5:95 to 95: 5, and further preferably 10:90 to 90:10. When mixed and used within the above range, the value of the triboelectric charge amount becomes more stable than when either one is used alone, and due to fog of yellow toner on the image background portion caused by poor charging, and further due to hue shift, etc. It is less likely that the color reproducibility of an intermediate color such as a skin color will be deteriorated and the image quality will not be deteriorated.

Further, in the present invention, compound No. (1) and compound No. It was found that the stability of the triboelectric chargeability of the yellow toner is further improved by using the polyester resin as the binder resin for (2).

It is particularly preferable to use a polyester resin having the composition shown below. That is, the polyester resin contains 45 to 55 mol% of a diol component and 55 to 45 mol%.
Those prepared from mol% of carboxylic acid component are preferable.

In this case, it is preferable to use a bisphenol derivative represented by the following formula (3) or a substitution product thereof as the diol component.

[0017]

[Outside 6] (In the formula, R is an ethylene group or a propylene group, x and y are each an integer of 1 or more, and the average value of x + y is 2 to 10.)

As the carboxylic acid, dicarboxylic acids such as fumaric acid, maleic acid, maleic anhydride, phthalic acid and terephthalic acid, polycarboxylic acids such as trimetic acid and pyromellitic acid, or acid anhydrides thereof or lower Preference is given to using alkyl esters.

The polyester resin obtained from the above-mentioned carboxylic acid component and alcohol component exhibits sharp melting characteristics, so that it has good color mixing property as a yellow toner for full color and heat roller fixing, and also has excellent offset resistance. However, the compound No. (1) and compound No. The dispersibility of (2) is remarkably improved, whereby not only the negative triboelectric charge amount with respect to the yellow toner particles is stabilized, but also the effect of improving coloring and increasing saturation is obtained.

Further, in consideration of the storability of the yellow toner, the glass transition temperature of the polyester resin obtained here is preferably 50 to 75 ° C, more preferably 52 to 65 ° C.

Further, the polyester resin has a number average molecular weight (Mn) of 1,500 to 50,000, preferably 2,
000-20,000, weight average molecular weight (Mw) is 6,
000-100,000, preferably 10,000-9
It is preferable that it is 50,000 and Mw / Mn is 2-8. A polyester resin satisfying the above conditions has a good heat fixing property, improves the dispersibility of the coloring component, reduces the fluctuation of the charge amount of the yellow toner, and improves the reliability of the image quality. Thus, compound No. (1), and compound N
o. When the yellow colorant (2) and the polyester resin as the binder resin component are mixed and the toner particles are obtained through a manufacturing process such as kneading, pulverizing and classifying, the compound No. (1) and compound No.
The total amount of (2) is 1 to 15 per 100 parts by weight of the binder resin.
Parts by weight, preferably 3 to 10 parts by weight, more preferably 4
It is recommended to use up to 8 parts by weight. If it is more than 15 parts by weight, the transparency is lowered, especially the transparency and the color reproducibility are lowered, and the reproducibility of the intermediate color typified by human skin color is apt to be lowered. Furthermore, the chargeability of the toner becomes unstable, and it becomes difficult to obtain the target charge amount.

On the other hand, if the content is less than 1 part by weight, it is difficult to obtain the desired coloring power and it is difficult to obtain a high-quality image with high image density.

In the yellow toner of the present invention, a fluidity improver or the like may be added, and any material can be used as long as the fluidity can be increased by comparing before and after the addition. For example,
Fine powders of metal oxides such as silica fine powder, alumina fine powder, titanium oxide fine powder, zirconium oxide fine powder, magnesium oxide fine powder; boron nitride fine powder, aluminum nitride fine powder, carbon nitride fine powder, etc. Or a resin fine particle such as a silicone resin fine particle.

In the present invention, calcium titanate, strontium titanate, barium titanate, magnesium titanate, cerium oxide, zirconium oxide, aluminum oxide, titanium oxide, zinc oxide, calcium carbonate and the like are preferably used. Particularly preferably, a hydrophobized titanium oxide fine powder having an average primary particle diameter of 0.01 to 0.2 μm is used.

It is important that the above additives not only enhance the fluidity of the yellow toner, but also do not impair the chargeability of the yellow toner. That is, in the yellow toner of the present invention, the hydrophobized titanium oxide fine powder has an excellent flowability while maintaining the stable charging property of the yellow toner.

The average primary particle diameter of titanium oxide is 0.01 to
When it is 0.2 μm, the fluidity is good and the yellow toner is uniformly charged, and as a result, toner scattering and fogging are less likely to occur. Further, the toner is less likely to be embedded on the surface of the yellow toner particles and the toner deterioration is less likely to occur, and the durability of many sheets is improved. This tendency is more remarkable in the sharp melt yellow color toner used in the present invention. The particle size of titanium oxide was measured by a transmission electron microscope.

Further, since titanium oxide is hydrophobized, the influence of water, which is a factor that influences the charge amount, is eliminated, and the difference in the charge amount under high humidity and low humidity is reduced, thereby achieving environmental characteristics. In addition, it is possible to prevent the agglomeration of primary particles by adding a hydrophobizing treatment in the production process of titanium oxide, and it is possible to give a uniform charge to the yellow toner. The points are as follows.

In this case, as a method for hydrophobizing titanium oxide, there is a method in which hydrophilic titanium oxide is mechanically dispersed in an aqueous system so as to have a primary particle size while hydrolyzing the coupling agent. It is effective and preferable in that no organic solvent is used.

When the yellow toner of the present invention is combined with the above titanium oxide, the amount of titanium oxide added is 0.5 to 5.0% by weight, preferably 0.7 to 3.0% by weight, more preferably 1% by weight. 0 to 2.5% by weight is preferable. When the above range is satisfied, the flowability of the yellow toner is good, a stable charge amount can be maintained, and toner scattering hardly occurs.

The yellow toner of the present invention has a weight average particle size of 6 to 10 μm, 15 to 45% by number of yellow toner particles having a particle size of 5 μm or less, and a particle size of 12.7 to 1.
It is preferable that the content of the yellow toner particles of 6.0 μm is 0.1 to 5.0% by volume, and the content of the yellow toner particles of 16 μm or more in particle diameter is 1.0% by volume or less.

The yellow toner having the above particle size distribution is
It is possible to further enhance the effect of obtaining stable charging ability in the characteristics of the material itself. That is, the yellow toner of the present invention has a very sharp charge distribution of the yellow toner itself by having the above-mentioned particle size distribution in addition to the stabilization of the charge, thereby not only improving the developing efficiency but also copying. The effect of drastically reducing the so-called "fog" in the background portion of the image can also be obtained.

As a further effect, it is possible to faithfully reproduce the latent image formed on the photoconductor, and also excellent in the reproducibility of minute dot latent images such as halftone dots and digital images. The yellow toner of the present invention can provide a toner image having excellent gradation and resolution in the light area. Further, even if the image is continuously output, high image quality is maintained, and even in the case of a high-density image, good development can be performed with a small toner consumption amount. It can also contribute to miniaturization.

It has been considered that it is difficult to control the charge amount of yellow toner particles having a particle size of 5 μm or less, the fluidity of the yellow toner is reduced, and a fog component on the image background portion is generated. Toner particles are important for forming high quality images.

Actually, the developed yellow toner was collected in the latent image potential portion on the photosensitive member and the particle size distribution was measured. As a result, many yellow toner particles having a particle size of 8 μm or less, particularly a particle size of 5 were obtained.
Many yellow toner particles of about μm are present in the fine dot portion.
This is true to the latent image when yellow toner particles having a particle diameter of about 5 μm are smoothly supplied to the development of the latent image on the photoconductor, and an image with truly excellent reproducibility is obtained without protruding from the latent image. Be done.

When the yellow toner of the present invention has a negative chargeability, it is preferable to add a charge control agent for the purpose of further stabilizing the negative charge characteristic. Examples of the negative charge control agent include colorless or pale-colored organometallic complexes such as metal complexes of alkyl-substituted salicylic acid (for example, chromium complex of diethyl butylsalicylic acid, zinc complex, or aluminum complex).

When the toner has a positive charging property, it is preferable to contain a charge control agent showing a positive charging property. For example,
Examples thereof include triphenylmethane-based compounds, rhodamine-based dyes, and polyvinylpyridine, and it is particularly preferable to use a colorless or light-colored positive chargeability control agent that does not affect the color tone of the toner.

When these charge control agents are contained in the toner, the content thereof is preferably in the range of 3% by weight to 10% by weight, preferably 4% by weight to 8% by weight. It is not necessarily limited as long as it does not affect the color tone.

When the charge control agent is used in the above content, the initial fluctuation of the charge amount is small, and the absolute charge amount required at the time of development is easily obtained, and as a result, the image quality such as "fog" and image density reduction may be impaired. Absent.

Further, if necessary, a fatty acid metal salt as a lubricant, such as zinc stearate, aluminum stearate or the like, 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.

Further, it does not matter if a release agent is further contained as a fixing aid. For example, an aliphatic hydrocarbon wax,
Oxides of aliphatic hydrocarbon waxes, waxes containing fatty acid ester as a main component, saturated linear fatty acids, unsaturated fatty acids, saturated alcohols, polyhydric alcohols, fatty acid amides, saturated fatty acid bisamides, Examples thereof include saturated fatty acid amides and aromatic bisamides. In this case, the amount of the release agent 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. This is because when the amount of the release agent exceeds 20 parts by weight, the blocking resistance and the high temperature offset resistance are likely to decrease, while when it is less than 0.1 parts by weight, the releasing effect is small.

Further, these release 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. Is preferred.

The yellow toner of the present invention is preferably mixed with a carrier and used as a two-component developer. As the carrier, for example, surface-oxidized or non-oxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, chromium, calcium, magnesium, rare earths, alloys or oxides thereof, and magnetic ferrite can be used. The material of the magnetic particles used as a carrier is Cu-Zn-Fe (metal composition ratio (5 to 20) :( 5
~ 20): (30 to 80)) ferrite particles are preferable because the surface can be easily made uniform and the charging ability is stable. However, it is not particularly limited, in addition to other flat, spongy, coin-like, spherical, spherical iron powder of various shapes such as spherical, copper, manganese, nickel, zinc, tin, magnesium, lead, strontium, It is possible to use ferrite containing one or more of barium, lithium, calcium and the like, particles made of a mixture of various resins and magnetic powder, and the like.

A system in which the surface of the carrier is dipped 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 solvent and applying the coating material and attaching it to a carrier, or a method of simply mixing with a powder can be applied.

An electrically insulating resin is used as a substance adhered to the surface of the carrier, and is appropriately selected according to the toner material and the carrier core material. In this case, at least acrylic acid (or its ester) is used in order to improve the adhesiveness with the carrier surface.
It is necessary to contain at least one monomer selected from monomers and methacrylic acid (or ester thereof) monomers. 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.
It is preferable that the copolymer of styrene-based monomers is 5 to 70% by weight.

Examples of usable carrier coating resin monomers include, for example, styrene monomer, chlorostyrene monomer, α-methylstyrene monomer, styrene-
There are chlorostyrene monomers 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,
Examples thereof include phenyl acrylate monomers and 2-ethylhexyl acrylate monomers), and methacrylic acid ester monomers (methyl methacrylate monomers, ethyl methacrylate monomers, butyl methacrylate monomers, phenyl methacrylate monomers) and the like.

The coating material for these carriers is relatively suitable for the yellow toner of the present invention, but is not necessarily limited thereto, and is useful for preventing spent on the carrier such as toner fusion. Any conceivable resin having a small surface energy may be used. For example, fluororesin, silicone resin, etc. may be mentioned. In order to enhance the adhesiveness to the carrier core material, it is preferable to use various additives in combination to enhance the toughness of the coating. In particular, when coating the silicone resin, by adding water to the coating resin diluting solvent used, the durability and charging characteristics of the obtained coated carrier are further improved.

This is because the crosslinking point of the curable silicone resin and the hydrolysis of the silane coupling agent are promoted, the curing reaction proceeds further, and the surface energy of the silicone resin increases for a short period of time, and the carrier energy This is due to the improved adhesiveness of.

The coating amount of the above-mentioned coating resin with respect to the carrier is such that the resin solid content is 0.05% by weight to 10% by weight, preferably 0.1% by weight to 5% by weight.

The average particle size of the carrier is 27 to 100.
μm, preferably 25 to 70 μm, more preferably 25
It is preferable to have a thickness of ˜65 μm. The measurement is performed using an SRA type of Microtrac particle size analyzer (Nikkiso Co., Ltd.) in a range setting of 0.7 to 125 μm.

When a two-component type developer is prepared by mixing the yellow toner of the present invention with the above-mentioned carrier, the mixing ratio is 1% by weight to 12% as the toner concentration in the developer.
Good results are usually obtained at weight percentages, preferably between 2 wt% and 9 wt%. If the toner concentration is less than 1% by mass, the image density tends to be low, and if it exceeds 12% by weight, fog or scattering in the machine tends to occur, and the useful life of the developer is apt to be shortened.

Method for measuring molecular weight The column was stabilized in a heat chamber at 40 ° C., and tetrahydrofuran as a solvent was flown through the column at this temperature at a flow rate of 1 ml / min to prepare a THF sample solution. Inject 100 μl and measure. When measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value and the count number of a calibration curve prepared from several kinds of monodisperse polystyrene standard samples. As a standard polystyrene sample for preparing a calibration curve, for example, a standard polystyrene sample having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh or Showa Denko is used, and it is suitable to use a standard polystyrene sample of at least about 10 points. is there. An RI (refractive index) detector is used as the detector. As a column, it is better to combine multiple commercially available polystyrene gel columns.
For example, shodex GPC KF-8 manufactured by Showa Denko KK
01, 802, 830, 804, 805, 806, 80
Combination of 7,800P and TSKge manufactured by Tosoh Corporation
lG1000H (H _XL ), G2000H (H _XL ), G3
000H (H _XL ), G4000H (H _XL ), G5000
H (H _XL ), G6000H (H _XL ), G7000H (H
XL) and TSKguardcolumn can be mentioned.

The sample is prepared as follows.

The sample is placed in THF, left to stand for several hours, shaken well, thoroughly mixed with THF (until the coalescence of the sample disappears), and left still for 12 hours or more. At this time T
The time of leaving in HF should be 24 hours or more.
Then sample processing filter (pore size 0.45
~ 0.5 μm, for example, Mysholydisk H-25-
5 Tosoh Corp., Excicro Disc 25CR Gelman Science Japan Ltd., etc. can be used. ) Is used as a sample of GPC. The sample concentration is
The resin component is adjusted to 0.5 to 5 mg / ml.

Measuring method of glass transition point It is carried out according to ASTM D3418-82. As the DSC curve, a DSC curve measured when the temperature is raised at a temperature rate of 10 ° C./min after the temperature is raised and lowered once to take a previous history is used.

The glass transition point (Tg) is DSC at the time of heating.
The temperature at the intersection of the DSC curve and the line connecting the midpoints of the baseline before and after the specific heat change appears on the curve is adopted.

Measuring Method of Triboelectric Charge A measuring method will be described in detail with reference to the drawings.

FIG. 1 is an explanatory view of an apparatus for measuring the triboelectric charge amount. First, in a metal measuring container 2 having a 500 mesh screen 3 on the bottom, a mixture of a toner and a carrier, whose weight ratio is 1:19, whose triboelectric charge amount is to be measured, and in the case of an external additive, is 1: The mixture of 99 is put in a polyethylene bottle of 50 to 100 ml and shaken by hand for about 10 to 40 seconds, and about 0.5 to 1.5 g of the mixture (developer) is put into the lid 4 made of metal. . The weight of the entire measuring container 2 at this time is represented by a scale w ₁ (g). Next, in the suction device 1 (at least the portion in contact with the measurement container 2 is an insulator), suction is performed from the suction port 7 and the air volume control valve 6 is adjusted to adjust the pressure of the vacuum gauge 5 to 25
It is set to 0 mmAq. In this state, the toner is suctioned sufficiently, preferably for 2 minutes to remove the toner by suction. The potential of the electrometer 9 at this time is V (volt). Here, 8 is a capacitor, and the capacity is C (mF). The mass of the entire measuring container after suction is weighed and is W ₂ (g). The triboelectric charge amount (mC / kg) of this toner is calculated by the following equation.

Toner triboelectric charge amount (mC / kg) = C ×
V / (W ₁ -W ₂ ) (However, the measurement conditions are 23 ° C. and 60% RH.) The carrier used for the measurement is 250 mesh bath, 35
A coated ferrite carrier with 70-90% by weight of 0 mesh on carrier particles is used.

Coulter Counter TA- or Coulter Multisizer (manufactured by Coulter) is used as a measuring device for measuring the toner particle size distribution . The electrolyte is approximately 1% N using first-grade sodium chloride.
Prepare an aCl aqueous solution. For example, ISOTON, R-
(Coulter Scientific Japan) can be used. As a measuring method, the electrolytic aqueous solution 100 to
As a dispersant, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) is added to 150 ml, and 2 to 20 mg of a measurement sample is further added. The electrolytic solution in which the sample is suspended is subjected to a dispersion treatment with an ultrasonic disperser for about 1 to 3 minutes.
Using a μm aperture, the volume and number of toner particles are measured for each channel, and the volume distribution and number distribution of toner are calculated. Then, the weight average particle diameter (D4) of the toner based on the weight determined from the volume distribution of the toner particles.
(The median value of each channel is used as a representative value for each channel).

The channels are 2.00 to 2.52.
μm; 2.52 to 3.17 μm; 3.17 to 4.00 μm
m; 4.00 to 5.04 μm; 5.04 to 6.35 μ
m; 6.35 to 8.00; 8.00 to 10.08 μm;
10.08-12.70 μm; 12.70-16.00
μm; 16.00 to 20.20 μm; 20.20 to 2
5.40 μm; 25.40-32.00 μm; 32-4
13 channels of 0.30 μm are used.

Method for Measuring Average Particle Size of Titanium Oxide Fine Particles The primary particle size is determined by observing the titanium oxide fine particles with a transmission electron microscope and measuring 100 particle sizes in the visual field to obtain the average particle size. The above-mentioned dispersed particle diameter is observed by a scanning electron microscope, 100 titanium oxide fine particles in the visual field are qualitatively determined by XMA, and the particle diameter is measured to obtain the average particle diameter.

Method for measuring hydroxyl value : The hydroxyl value is measured according to the method described in JIS K007 by the following method.

6 g of the 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 was attached to the mouth of the Erlenmeyer flask, and 10
React for 90 minutes in an oil bath at 0 ° C.

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 was pulled up from the oil bath and allowed to cool, and when cooled to about 30 ° C, a small amount of acetone (10
The condenser and the mouth of the flask are washed with (about ml). THF
Add 50 ml with a graduated cylinder and use N / 2KOH-THF as an alcohol solution of phenolphthalein.
Neutralize titration with the solution using a 50 ml (0.1 ml scale) burette. 25m of neutral alcohol just before the end point of neutralization
1 (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.

Hydroxyl value (mgKOH / g) = [(B-
A) × f × 28.05 / S] + C where A: ml number of N / 2KOH-THF solution required for this test B: ml number of N / 2KH-THF solution required for blank test f: N / Titer of 2KOH-THF solution S: sampling amount (g) C: acid value or alkali value. However, the acid value is positive and the alkali value is negative.

Take the average of the two measurements.

[0069]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. In the text, "part" and "%" are all "part by weight" and "% by weight".

Example 1 Polyester resin A produced by condensation reaction of propoxylated bisphenol A and fumaric acid (described in Table 1)
100 parts by weight Compound No. (3) and compound No. 9: 1 for (4)
7 parts by weight of a blended product in a weight ratio of 4 parts by weight of a negative charge controlling agent (chromium complex compound). The above materials are sufficiently premixed by a Henschel mixer, melt-kneaded by a twin-screw extruder, and cooled and hammered. A mill was used to roughly pulverize about 1-2 nm, and then finely pulverized by an air jet type fine pulverizer. Further, the finely pulverized product thus obtained was subjected to strict removal of fine powder and coarse powder simultaneously with a multi-division classifier to obtain a yellow toner having a particle size distribution shown in Table 1.

On the other hand, as a fluidity improver, n-C ₄ H _{9 was} added to 100 parts by weight of hydrophilic titanium oxide fine powder (average primary particle diameter 0.02 μm, BET specific surface area 140 m ² / g).
-Si- (OCH _{3) 3} was surface treated using 20 parts by weight, an average primary particle diameter of 0.02 [mu] m, 70% hydrophobicity and transmittance of 60 percent at the wavelength 400nm hydrophobic titanium oxide fine body Obtained.

100 parts by weight of the yellow toner and 1.5 parts by weight of the hydrophobic titanium oxide fine powder were mixed to prepare a negatively chargeable yellow toner having the hydrophobic titanium oxide fine powder on the surface of the yellow toner particles.

The above yellow toner and Cu-Zn-Fe based magnetic ferrite carrier particles surface-coated with a silicone resin were mixed so as to have a toner concentration of 5% by weight to obtain a yellow two-component developer.

A commercially available plain paper full-color copying machine (color laser copying machine CLC80) was used as the yellow two-component developer.
No. 0, manufactured by Canon Inc.), a negative triboelectric charge was applied to the yellow toner, and a copy test was conducted. Even in the durability test of 50,000 sheets, the image density was as high as 1.7 to 1.8. Concentration is shown and there is little initial fluctuation in charging characteristics, about -20 mC
/ Kg to -25 mC / kg remained stable.
In addition, since the hue of the yellow toner itself is small, even when a full-color image including cyan toner, magenta toner, and black toner is output, the reproduction of intermediate colors is excellent, and a copy image with a clear tint is obtained. Was obtained.

Example-2 Compound No. (3) and compound No. A yellow toner having a particle size distribution shown in Table 2 was obtained in the same manner as in Example 1 except that the blend ratio of (4) was changed to 7: 3.

When the yellow toner was evaluated in the same manner as in Example 1, the color tone of the copied image was slightly shifted to reddish, but the image density was stable at 1.6 to 1.7. The image quality was high and excellent in saturation, and even in the durability test of 50,000 sheets, a copy image faithful to the original image with less fog was obtained, and the image quality was satisfied. At this time, the triboelectric charge amount was -23 mC / kg to -26 mC / kg.

Example-3 An example except that the hydrophobic titanium oxide fine powder was reduced to 1.0 part by weight and the toner particle size distribution was as shown in Table-1. A yellow toner was prepared in the same manner as in 1.

When the yellow toner was evaluated in the same manner as in Example 1, the reproducibility in the halftone part was slightly lowered, but there was almost no problem at the visible level on the copied image, and the total charge amount was also. A stable value was exhibited in the durability test of 50,000 sheets. In addition, the hue of yellow did not extremely shift in the red and green directions, and the image density was as high as 1.6 to 1.8, and a clear image was obtained.

Example 4 Yellow toners shown in Table 1 were obtained and evaluated in the same manner as in Example 1 except that hydrophobic titanium oxide having a primary average particle diameter of 0.05 μm was used. As a result, although the "roughness" in the highlight part is conspicuous because the fluidity of the toner is slightly lowered, the triboelectric charge amount is stable at -26 mc / kg to -28 mC / kg.
Since the image density was as high as 1.7 to 1.8, the image texture was improved and a clear tint was exhibited.

Example 5 Hydroxyl value was 20.4, weight average molecular weight (Mw) was 110000, and number average molecular weight (Mn) was 5540.
And the yellow toners shown in Table 1 were obtained in the same manner as in Example 1 except that the polyester resin having a ratio Mw / Mn of about 19.9 was used, and evaluated in the same manner as in Example 1. . Since the polyester resin is hard, the glossiness after fixing was slightly reduced, and the texture of the full-color image was slightly different, but there was no hue shift and the color tone was clear, and the highlight reproducibility for the halftone, which is the most affected yellow toner. Has improved.

Example 6 Styrene-n-butyl acrylate copolymer resin (T
g = 60 ° C.) 100 parts by weight Compound No. (3) and compound No. (4) to 9.
2: 0.8 parts by weight of blended product 7 parts by weight-Negatively charged property control agent (chromium complex compound) 4 parts by weight The above materials were subjected to the same steps as in Example-1 to give the particle sizes shown in Table-1. A yellow toner having a distribution was obtained, a two-component developer for yellow color was prepared, and a copying test was carried out with a commercially available full-color copying machine (color laser copying machine CLC800) in the same manner as in Example 1. Although the amount decreased, it was within the practical level even after 10,000 sheets of running, but some fog occurred.

Example-7 Compound No. (3) and compound No. A yellow toner having a particle size distribution shown in Table 1 was obtained in the same manner as in Example 1 except that the mixing weight ratio with (4) was changed to 3: 7.

When evaluated in the same manner as in Example 1, it showed a high image density even in a test under a low temperature and low humidity environment.
Even in the continuous durability test of 50,000 sheets, the tendency did not change and stable images were obtained. Table 2 shows the results.

Example-8 Compound No. (3) and compound No. A yellow toner having a particle size distribution shown in Table 1 was obtained in the same manner as in Example 1 except that the mixing weight ratio with (4) was changed to 1: 9.

When evaluated in the same manner as in Example 1, although the initial charge amount was slightly low, it showed good durability stability, and the 50,000 images after durability had no fog and high saturation. Met.

In a durability test under a high temperature and high humidity environment, after about 10,000 sheets, some toner scattering was seen, but it was within a practical level and the image density was as high as 1.7 to 1.8. It was stable.

Comparative Example-1 The following formula

[0088]

[Outside 7] C. I. Pigment Yellow 74
Was used in the same manner as in Example 1 except that 100 parts by weight of polyester resin A was used in the same manner as in Example 1 to obtain a yellow toner having a particle size distribution shown in Table-1 and evaluated in the same manner as in Example 1. Although a stable charge amount was obtained in the durability test of 50,000 sheets, the absolute value was -30 mC / kg.
It was as high as ˜-33 mC / kg, which resulted in poor saturation and low image density of 1.0-1.2, resulting in poor image quality.

Comparative Example-2 The following formula

[0090]

[Outside 8] C. I. Pigment Yellow 93
A yellow toner having a particle size distribution shown in Table 1 was obtained in the same manner as in Example 1 except that 5 parts by weight of polyester resin A was used in an amount of 5 parts by weight, and evaluated in the same manner as in Example 1. The initial image had a high density and was within a practical level, but the image density gradually decreased during the durability of many sheets. Further, the obtained yellow image was discolored in the weather resistance test by ultraviolet irradiation.

Comparative Example-3 100 parts by weight of polyester resin A produced by condensation reaction of propoxylated bisphenol A and fumaric acid Compound No. (2) 7 parts by weight-Negatively charged property control agent (chromium complex compound) 4 parts by weight The above materials were subjected to the same steps as in Example-1 to obtain a yellow toner having a particle size distribution shown in Table-1 for yellow color. A two-component developer was prepared and a copying test was conducted in the same manner as in Example 1. As a result, the yellow toner charge amount decreased from the time of about 1,000 sheets of the durability test, and the yellow toner fogging on the image background portion was thereby caused. increased.

Comparative Example 4 100 parts by weight of polyester resin A produced by condensation reaction of propoxylated bisphenol A and fumaric acid Compound No. (1) 7 parts by weight ・ Negatively charged property control agent (chromium complex compound) 4 parts by weight The above materials were subjected to the same steps as in Example-1 to obtain a yellow toner having a particle size distribution shown in Table-1 for yellow color. When a two-component developer was prepared and a copying test was conducted in the same manner as in Example 1, a durability test proceeded without problems under the environment of a temperature of 23 ° C. and a humidity of 60% RH, but a temperature of 15 ° C. and a humidity of 10
In a low temperature and low humidity environment of% RH, the charge amount of the yellow toner increased to -40 mC / kg or more during the endurance test, and the low image density and roughness were noticeable.

The results of each Example and Comparative Example are shown in Table 2.

[0094]

[Table 1]

[0095]

[Table 2]

[0096]

EFFECT OF THE INVENTION Binder resin and two compound Nos. (1)
And (2) [preferably compound No. The yellow toner of the present invention containing a blended pigment obtained by blending (3) and (4)] is excellent in triboelectric charging property and can achieve high image density and high durability.
It is possible to provide a yellow image and a full-color image having a clear tint.

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of an apparatus for measuring a triboelectric charge amount of a toner or an external additive.

Claims (12)

[Claims] 1. At least a binder resin and a compound No. 1 represented by the following formula (1). (1) and the compound No. represented by the following formula (2). A yellow toner comprising yellow toner particles containing (2). [Outside 1] 2. Compound No. Compound (1) is represented by the following formula (3). The yellow toner according to claim 1, which is (3). [Outside 2] 3. Compound No. (2) is represented by the following formula (4) and compound No. The yellow toner according to claim 1, which is (4). [Outside 3] 4. Compound No. (1) and compound No.
4. The yellow toner according to claim 1, wherein (2) is mixed in a weight ratio of 1:99 to 99: 1. 5. Compound No. (1) and compound No.
The yellow toner according to claim 4, wherein (2) and (2) are mixed in a weight ratio of 5:95 to 95: 5. 6. Compound No. (1) and compound No.
The yellow toner according to claim 1, wherein (2) is mixed in a weight ratio of 10:90 to 90:10. 7. A compound N based on 100 parts by weight of a binder resin.
o. (1) and compound No. Mixture with (2) is 1-15
The yellow toner according to any one of claims 1 to 6, which is contained in an amount by weight. 8. The yellow toner according to claim 1, wherein the binder resin is a polyester resin. 9. The polyester resin comprises a diol component (45) selected from (i) a bisphenol derivative or a substitution product.
A polyester resin produced by polycondensing 55 mol% of (ii) a carboxylic acid component selected from (ii) a dicarboxylic acid anhydride, or a lower alkyl ester of dicarboxylic acid of 55 to 45 mol%. Has 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.
And the value of Mw / Mn is 2-8.
The yellow toner according to any one of 1. 10. The yellow toner according to claim 1, wherein the yellow toner particles are mixed with hydrophobic titanium oxide fine particles having a primary particle diameter of 0.01 to 0.2 μm. 11. The weight average particle diameter of the yellow toner is 6 to.
15 to 45% by number of yellow toner particles having a particle diameter of 5 μm or less are contained, and the particle diameter is 12.7 to 16.0.
0.1 to 5.0% by volume of yellow toner particles having a diameter of 16 μm and 1.0
The yellow toner according to claim 1, wherein the yellow toner is contained in an amount of not more than volume%. 12. The yellow toner according to claim 1, which has a negative charging property.