JP2001194828A - Electrostatic charge image developing color toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide electrostatic charge image developing color toner by which a stable image of low luster can be obtained while giving sufficient fixation and a stable image of high luster can be obtained without substantially changing fixing conditions in a fixing system which changes luster degree of the image by changing heat quantity and pressure given to the toner. SOLUTION: The electrostatic charge image developing color toner is distinguished by containing a resin A which contains at least a binder resin and a colorant, in which endothermic peak temperature of the binder resin in a differential scanning calorimeter(DSC) is in a range between 55 deg.C and 75 deg.C, a maximum peak in molecular weight distribution by gel permeation chromatography(GPC) is in a molecular weight range between 5000 to 20000 and components having molecular weight of >=1×105 is 3 to 20 wt.%, and a resin B which has endothermic peak temperature in DSC higher than the endothermic peak temperature of the resin A by the DSC by at least 10 deg.C, a maximum peak in molecular weight distribution by the GPC is in a molecular weight range between 500 to 5000 and which has no component having molecular weight of >=1×105.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, etc., and more particularly, to an electrostatic image development suitable for an apparatus having a heat fixing mechanism. And color toners.

[0002]

2. Description of the Related Art In recent years, the technology of copying and printing using an electrophotographic system has been rapidly expanding from monochrome to full color, and the market for full color has been expanding. Color image formation by full-color electrophotography generally reproduces all colors by laminating three color toners of three primary colors, yellow, magenta, and cyan, or four color toners with black added thereto. .
Therefore, in order to obtain a high-quality full-color image, the fixing characteristics to be possessed by the color toner are extremely important factors. For example, in order for a fixed color toner to produce vivid color, it is necessary that the fixed toner surface has a smooth and appropriate gloss in order to suppress light scattering on the surface of the fixed toner image as much as possible. Further, in order not to hinder the color development of the toner having a different color tone under the toner layer, it is necessary to prevent light scattering inside the toner layer, and transparency is required. In order to obtain such a clear and wide color reproduction image, the fixing toner layer needs to have gloss and transparency.

[0003] On the other hand, in conventional monochrome images, image gloss is not preferred due to the fact that the eyes are easily tired, and it is generally desirable that color characters inserted in text or simply color-coded tables and graphs have no image gloss. Preferred.

For this reason, Japanese Patent Application Laid-Open No. Hei 6-202520 proposes an image forming apparatus capable of changing the gloss of an image in accordance with a user's specification and automatically reproducing gloss close to the gloss of a document. The means for changing the image gloss is a fixing temperature, a fixing nip width or a fixing speed. In short, the amount of heat applied to the toner is changed. However, a general full-color using a low molecular weight binder resin which originally provides a high gloss can be obtained. When the gloss of the toner is reduced, the toner does not sufficiently adhere to the transfer paper, resulting in poor fixing. Conversely, a low-gloss toner in which a high molecular weight component or a cross-linking component is introduced into a binder resin cannot achieve high gloss or requires a large change in fixing temperature, nip width, and speed, resulting in too large a practical problem. A toner that introduces a moderately high molecular weight component into a low molecular weight binder resin or uses a medium molecular weight resin to obtain a fine gloss to a medium gloss is suitable for such an image gloss switching method, but a stable low gloss image is obtained. It is difficult for the obtained toner to obtain a sufficiently high gloss, and for a toner capable of stably obtaining a high gloss image, a sufficiently low gloss image cannot be obtained in consideration of fixability. In addition, JP-A-8-278658, JP-A-11-52611,
11-52615, JP-A-11-52616 mainly aimed at low-temperature fixability,
It has been proposed to use a hydrogenated petroleum resin as a binder resin for a toner, but none of them can obtain a low gloss image and a high gloss image in a stable and responsive manner unlike the embodiment of the present invention.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, that is, it provides a stable fixing while giving sufficient fixing property to a fixing method for changing the glossiness of an image by changing the amount of heat or pressure applied to the toner. SUMMARY OF THE INVENTION It is an object of the present invention to provide a color toner for developing an electrostatic image capable of obtaining a stable low gloss image and obtaining a stable high gloss image without largely changing fixing conditions.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, have found that a specific DSC
The inventors have found that the object can be achieved by combining two kinds of binder resins having an endothermic peak and a specific molecular weight distribution, and have reached the present invention.

That is, according to the present invention, (1) at least a binder resin and a colorant are contained, the binder resin has an endothermic peak temperature in a DSC range of 55 to 75 ° C., and a maximum peak in a molecular weight distribution by GPC. But,
It has a molecular weight of 5,000 to 20,000 and a molecular weight of 1
× 10 ⁵ or more ingredients is high at least 10 ° C. or higher than the endothermic peak temperature in DSC endothermic peak temperature of the resin A in the resin A and DSC present 3 to 20 wt%, GP
The maximum peak in the molecular weight distribution due to C is 50 molecular weight.
A color toner for developing an electrostatic image, wherein the resin B is a hydrogenated petroleum resin which contains a resin B having a molecular weight of 1 × 10 ⁵ or more and having a molecular weight of 1 × 10 ⁵ or more. (3) a color toner for developing an electrostatic image, wherein the ratio of the resin B to the total binder resin in the toner is 3 to 35% by weight; Is provided.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. As the binder resin used in the toner of the present invention, conventionally known binder resins can be widely used. For example, styrene, parachlorostyrene, vinyl toluene,
Vinyl chloride, vinyl acetate, vinyl propionate, methyl (meth) acrylate, ethyl (meth) acrylate,
Propyl (meth) acrylate, n- (meth) acrylate
Butyl, isobutyl (meth) acrylate, dodecyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, 2-chloroethyl (meth) acrylate, (meth) acrylonitrile, (meth) acrylamide,
(Meth) acrylic acid, vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl methyl ketone, N-vinyl pyrrolidone, N-vinyl pyridine, a weight body of a monomer such as butadiene, or a monomer thereof. Copolymers of two or more types, or mixtures thereof, may be mentioned. In addition, a polyester resin, a polyol resin, a polyurethane resin, a polyamide resin, an epoxy resin, a rosin, a modified rosin, a terbene resin, a phenol resin, a hydrogenated petroleum resin, and the like can be used alone or in combination. As the binder resin A, a polyester resin, an epoxy resin, a polyol resin, and a copolymer of styrene and an alkyl (meth) acrylate are preferably used. As the binder resin B, a resin incompatible with the resin A is selected, and a hydrogenated petroleum resin is particularly preferably used. The hydrogenated petroleum resin referred to in the present invention is a resin obtained by reducing the unsaturated bonds remaining in the petroleum resin by adding hydrogen thereto. A petroleum resin is obtained by naphtha cracking from a petroleum unsaturated hydrocarbon obtained by refining a cracked oil fraction by-produced when producing ethylene, acetylene, propylene and the like. For example, aliphatic petroleum resins using C4-C6 aliphatic hydrocarbons as raw materials, aromatic petroleum resins using C8-C10 aromatic hydrocarbons as raw materials, cyclopentadiene-based petroleum resins, alicyclic aliphatic-based petroleum resins, etc. There is.

In the present invention, the DSC endothermic peak temperature is in the range of 55 to 75 ° C., and the maximum peak in the molecular weight distribution by GPC is 5,000 to 200.
3 and a component having a molecular weight of 1 × 10 ⁵ or more
When a toner is prepared using only the resin A which is present in an amount of from 20 to 20% by weight, an image with low gloss to low gloss can be obtained.
The endothermic peak temperature is at least 10 ° C. higher than the endothermic peak temperature in DSC of resin A, and the maximum peak in the molecular weight distribution by GPC is 500 to 5,000.
It has been found that by blending the resin B which does not have a component having a molecular weight of 1 × 10 ⁵ or more, gloss can be rapidly generated when the toner temperature becomes high. If the endothermic peak temperature of the resin A in the DSC is 55 ° C. or lower, there is a problem in the storability of the toner at a high temperature, and if the endothermic peak temperature in the DSC is 75 ° C. or more, there is a problem in the fixability of the toner. In addition, GP of resin A
The maximum peak in the molecular weight distribution due to C is 50
00 or less and 3 or more components having a molecular weight of 1 × 10 ⁵ or more.
When the content is less than 10% by weight, a low gloss image cannot be obtained, and the maximum peak in the molecular weight distribution by GPC is 2000 molecular weight.
0 or more and 20 or more components having a molecular weight of 1 × 10 ⁵ or more.
If the content is more than 10% by weight, a high gloss image cannot be obtained, or a large change in fixing temperature, nip width and speed is required, and practical problems are too large. The endothermic peak temperature of the resin B in DSC is at least one more than the endothermic peak temperature of the resin A.
By increasing the temperature by 0 ° C. or more, the gloss of the image can be sharply increased when the amount of fixing heat is increased, and the gloss is adjusted according to the conditions for generating the gloss. When the resin A and the resin B are compatible with each other, the effect of rapidly increasing the gloss when the amount of fixing heat is increased is not remarkable, and it is important that the resin A and the resin B are incompatible. The incompatibility between the resins can be confirmed by thinning the toner and observing it with a transmission electron microscope. The hydrogenated petroleum resin is easy to obtain a resin having a high Tg and a low molecular weight, and is excellent in terms of incompatibility with other resins, and the gloss switching effect of the present invention is remarkably exhibited. The amount of the resin B is adjusted in consideration of the molecular weight distribution of the resin A. When the maximum peak in the molecular weight distribution of the resin A by GPC is high and when there are many components having a molecular weight of 1 × 10 ⁵ or more, it is difficult to obtain an image gloss. Therefore, it is necessary to increase the blending amount of the resin B.

However, a low molecular weight resin such as resin B has low viscoelasticity at the time of melting, and if it is incorporated in a large amount into toner, the offset resistance when the fixing temperature is increased is lowered. Although it depends on the fixing device and the molecular weight distribution of the resin A and the resin B, the amount of the resin B is preferably set to 35% by weight or less in order to increase the gloss and provide the offset resistance at a high temperature. However, if the blending amount of the resin B is 3% or less, high gloss at a high temperature is not remarkable.

In the DSC curve of the present invention, the endothermic peak temperature and the amount of the component having a molecular weight of 1 × 10 ⁵ or more are determined by Rigaku Denki Co., Ltd.
With igaku THRMOFLEX TG8110,
The measurement was performed under the condition of a temperature rising rate of 10 ° C./min.

In the measurement of molecular weight by GPC, a column is stabilized in a heat chamber at 40 ° C., THF is passed through the column at this temperature at a flow rate of 1 ml per minute, and a sample concentration is 0.05 to 0.6. The measurement is performed by injecting 50 to 200 μl of a THF sample solution of the resin adjusted to the weight%. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve created from several types of monodisperse polystyrene standard samples and the count number. As standard polystyrene samples for creating calibration curves,
For example, Pressure Chemical Co. Or, the molecular weight manufactured by Toyo Soda Kogyo KK is 6 × 10 ² , 2.1 ×
10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ ,
1.1 × 10 ⁵ , 3.9 × 10 ⁵ , 8.6 × 10 ⁵ , 2 ×
10 ⁶ , 4.48 × 10 ⁶ , and at least 10 ⁶
It is appropriate to use about a few standard polystyrene samples. An RI (refractive index) detector is used as the detector.

The binder resin can be appropriately melt-mixed with a colorant and, if necessary, a charge control agent and other additives to form a toner for developing an electrostatic image.

As the colorant, known pigments and dyes capable of obtaining toners of yellow, magenta, cyan, and black can be used. For example, as a yellow pigment,
Cadmium yellow, mineral fast yellow, nickel titanium yellow, navels yellow, naphthol yellow S, Hanza yellow G, Hanza yellow 10
G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, tartrazine lake.

[0015] Examples of orange pigments include molybdenum orange, permanent orange GTR, pyrazolone orange, vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK.

Red pigments include red, red, cadmium red, permanent red 4R, lithol red, pyrazolone red, watching red calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin lake, and brilliant carmine 3B. No.

Examples of purple pigments include Fast Violet B and Methyl Violet Lake.

Examples of blue pigments include cobalt blue, alkali blue, Victoria Blue Lake, phthalocyanine blue, metal-free phthalocyanine blue, partially chlorinated phthalocyanine blue, fast sky blue, and indanthrene blue BC.

Examples of the green pigment include chrome green, chromium oxide, pigment green B, malachite green lake, and the like.

Examples of the black pigment include azine dyes such as carbon black, oil furnace black, channel black, lamp black, acetylene black, and aniline black, metal salt azo dyes, metal oxides, and composite metal oxides. These can be used alone or in combination of two or more.

Conventionally known charge control agents can be used in the toner of the present invention. For example, nigrosine, carbon number 2
Azine dyes containing up to 16 alkyl groups (Japanese Patent Publication No.
No. 1627), basic dyes (for example, CI Bas)
ic Yellow 2 (CI.41000), C.I.
I. Basic Yellow 3, C.I. I. Basic
Red 1 (CI. 45160), C.I. I. Basi
c Red 9 (CI. 42500), C.I. I. Ba
sic Violet 1 (CI. 42535),
C. I. Basic Violet 3 (CI.42
555), C.I. I. Basic Violet 10
(CI. 45170), C.I. I. Basic Vio
let 14 (CI. 42510), C.I. I. Bas
ic Blue 1 (CI. 42025), C.I. I.
Basic Blue 3 (CI. 50005),
C. I. Basic Blue 5 (CI. 4214)
0), C.I. I. Basic Blue 7 (CI.4
2595), C.I. I. BasicBlue 9 (C.I.
I. 52015), C.I. I. Basic Blue 2
4 (CI. 52030), C.I. I. Basic Bl
ue 25 (CI52025), C.I. I. Basi
c Blue 26 (CI.44045), C.I. I.
Basic Green 1 (CI. 42040),
C. I. Basic Green 4 (CI. 4200)
Lake pigments of these basic dyes, such as C.I. I.
Solvent Black 8 (CI. 2615)
0), quaternary ammonium salts such as benzoylmethylhexadecyl ammonium chloride and decyl trimethyl chloride; dialkyltin compounds such as dibutyl or dioctyl; dialkyltin borate compounds; guanidine derivatives; vinyl polymers containing amino groups; amino groups A polyamine resin such as a condensation polymer containing
JP-B-41-20153, JP-B-43-2759
No. 6, JP-B-44-6397, JP-B-45-6397.
Metal complex salts of monoazo dyes described in JP-A-26478, JP-B-55-42752, JP-B-59-7-7.
No. 385, salicylic acid, dialkylsalicylic acid, naphthoic acid, dicarboxylic acids Zn, Al,
Examples include metal complexes such as Co, Cr, and Fe, sulfonated copper phthalocyanine pigments, organic boron salts, fluorinated quaternary ammonium salts, and calixarene-based compounds.
For color toners other than black, the use of a charge control agent that impairs the intended color should of course be avoided, and a white salicylic acid derivative metal salt or the like is preferably used.

The toner of the present invention may contain a release agent typified by waxes in order to prevent winding and offset during fixing. Examples of the release agent include low-molecular-weight polyethylene, low-molecular-weight polypropylene, low-molecular-weight polyolefins such as oxidized polyethylene, beeswax, carnauba wax, montan wax, and other natural waxes,
Examples include higher fatty acids such as stearic acid, palmitic acid, and myristic acid, metal salts of higher fatty acids, and higher fatty acid amides.

These can be used alone or in combination of two or more, but those having a melting point in the range of 60 ° C. to 150 ° C. are preferably used. If the melting point is less than 60 degrees, the storage stability and blocking properties of the toner tend to be inferior. The use amount of these release agents is preferably about 0.5 to 20% by weight based on the toner.

In the present invention, it is preferable to externally add hydrophobic fine particles such as silica or titanium oxide to the toner matrix. A lubricant such as fine particles of a metal salt of a metal or polyvinylidene fluoride may be used in combination. The following are typical examples of the hydrophobizing agent used here.

Dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, allyldimethyldichlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, p-chloroethyl Trichlorosilane, chloromethyldimethylchlorosilane, chloromethyltrichlorosilane, p-chlorophenyltrichlorosilane, 3-chloropropyltrichlorosilane, 3-chloropropyltrimethoxysilane,
Vinyltriethoxysilane, vinylmethoxysilane, vinyl-tris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, divinyldichlorosilane, dimethylvinylchlorosilane, octyl-trichlorosilane,
Decyl-trichlorosilane, nonyl-trichlorosilane, (4-t-propylphenyl) -trichlorosilane, (4-t-butylphenyl) -trichlorosilane,
Dibentyl-dichlorosilane, dihexyl-dichlorosilane, dioctyl-dichlorosilane, dinonyl-dichlorosilane, didecyl-dichlorosilane, didodecyl-dichlorosilane, dihexadecyl-dichlorosilane, (4
-T-butylphenyl) -octyl-dichlorosilane,
Dioctyl-dichlorosilane, didecenyl-dichlorosilane, dinonenyl-dichlorosilane, di-2-ethylhexyl-dichlorosilane, di-3,3-dimethylbenzyl-dichlorosilane, trihexyl-chlorosilane, trioctyl-chlorosilane, tridecyl-chlorosilane, dioctyl-methyl-chlorosilane, Octyl-dimethyl-chlorosilane, (4-t-propylphenyl)
-Diethyl-chlorosilane, octyltrimethoxysilane, hexamethyldisilazane, hexaethyldisilazane, diethyltetramethyldisilazane, hexaphenyldisilazane, hexatolyldisilazane and the like. In addition, titanate-based coupling agents and aluminum-based coupling agents can also be used.

The toner of the present invention can be used for both one-component development and two-component development. When the toner of the present invention is used for a two-component developer, it is used by mixing with a carrier powder. As the carrier in this case, all known carriers can be used, and examples thereof include iron powder, ferrite powder, magnetite powder, nickel powder, glass beads, and the like, and those whose surfaces are coated with a resin or the like.

As a method for producing the toner of the present invention, a conventionally known method can be applied. As a device for kneading the toner, a batch type two-roll, a Banbury mixer or a continuous type twin-screw extruder, for example, Kobe Steel, Ltd. KTK twin screw extruder manufactured by Toshiba Machine Co., Ltd., TEM twin screw extruder manufactured by Toshiba Machine Co., Ltd., KCK 2
A screw extruder, a PCM type twin screw extruder manufactured by Ikegai Iron Works Co., Ltd., a KEX type twin screw extruder manufactured by Kurimoto Iron Works Co., Ltd., and a continuous single screw kneader, for example, a co-kneader manufactured by Buss Corporation are preferably used.

The melt-kneaded product obtained as described above is cooled and then pulverized. The pulverization is performed, for example, by coarsely pulverizing using a hammer mill or a rotoplex, and further using a fine pulverizer using a jet stream or a mechanical pulverizer. Can be used. It is desirable that the pulverization is performed so that the average particle size becomes 3 to 15 μm. Further, the pulverized product is adjusted to a particle size of 5 to 20 μm by an air classifier or the like. As needed,
The external additive is externally added to the base toner. The external additive is crushed by mixing and stirring the base toner and the external additive using a mixer, so that the external additive is coated on the toner surface.

As a fixing method used for the toner of the present invention, a conventionally known fixing method can be used, and a contact heating fixing method such as a hot roll fixing or a belt fixing is particularly preferable. This is because not only has the advantage of high heat efficiency and high-speed fixing can be performed, but also gloss and transparency can be easily selected by bringing a heat fixing member having a smooth surface into pressure contact. Materials with low surface energy, such as silicone rubber, Teflon, and PFA, are generally used on the surface of the heat-fixing member to enhance the releasability from the toner, and a release oil such as silicone oil is applied to further enhance the releasability. Often done. The toner of the present invention can exert its effect on any surface material of the heat-fixing member regardless of whether the release oil is applied.

[0030]

Next, the present invention will be described more specifically with reference to examples. Example 1 As resin A, the DSC peak temperature of terephthalic acid, fumaric acid, trimellitic anhydride, PO adduct of bisphenol A, EO adduct of bisphenol A was 66 ° C.,
A polyester resin was obtained in which the maximum peak in the GPC molecular weight distribution was 11,000 and the amount of the component having a molecular weight of 1 × 10 ⁵ or more was 14% by weight.

To 90 parts by weight of this resin, 10 parts by weight of resin B was a polystyrene resin having a DSC peak temperature of 85 ° C., a maximum peak in the GPC molecular weight distribution of 4,000, and a molecular weight of 1 × 10 ⁵ or more and 0% by weight. Parts, 3 parts by weight of a polyethylene wax having a melting point of 106 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge control agent), and 3 parts by weight of a copper phthalocyanine blue pigment (C.Ipigment Blue 15), followed by twin-screw extrusion. After cooling, the mixture was cooled, pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm.
For 100 parts by weight of the base toner, as an external additive,
0.5 parts by weight of hydrophobic silica (surface-treated with hexamethyldisilazane, primary particle size: 0.02 μm) was mixed with a Henschel mixer to obtain a cyan toner.

5 parts by weight of the toner and 95 parts by weight of the silicone resin-coated carrier were mixed and stirred to prepare a two-component developer. Using this developer, adjustment was performed so that a toner of 1.0 ± 0.1 mg / cm ² was developed in a Ricoh color copying machine Pretail 550, and a low gloss image having a fixing roller surface temperature of 160 ° C. When the image at the time was output, it was an image having almost no gloss, and the glossiness was 1.8. Next, as a high gloss image, the fixing roller surface temperature was 16
When 10 images were continuously output in the OHP mode at 0 ° C. and the fixing speed (linear speed) was １ ／, a glossy and clear image was obtained, and the glossiness of the first image was 25.4. Met. When ten images were continuously output, the surface temperature of the fixing roller decreased, but the glossiness of the tenth image was almost stable at 21.8. Next, the temperature was returned to the standard linear velocity, the temperature of the fixing roller was lowered from 160 ° C. to 5 ° C., and an image was sampled.
The fixability was satisfactory. The transfer paper used was Ricoh type 6000-70W paper, and the gloss was measured using a gloss meter manufactured by Nippon Denshoku Industries Co., Ltd.
It was measured at an incident angle of 60 °. In the fixing test, the image was rubbed with a cotton cloth and it was determined that the image was fixed if the cotton cloth was not stained.

Example 2 As resin A, the DSC peak temperature of terephthalic acid, fumaric acid, trimellitic anhydride, PO adduct of bisphenol A, and EO adduct of bisphenol A was 55 ° C.
A polyester resin having a maximum peak in the GPC molecular weight distribution of 5000 and a component having a molecular weight of 1 × 10 ⁵ or more of 12% by weight was obtained.

To 90 parts by weight of this resin, 10 parts by weight of a polystyrene resin having a DSC peak temperature of 85 ° C., a maximum peak in the GPC molecular weight distribution of 4,000, and a molecular weight of 1 × 10 ⁵ or more and 0% by weight as resin B were used. Parts, 3 parts by weight of a polyethylene wax having a melting point of 106 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge control agent), and 3 parts by weight of a copper phthalocyanine blue pigment (C.Ipigment Blue 15), followed by twin-screw extrusion. After cooling, the mixture was cooled, pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm.
0.5 part by weight of hydrophobic silica (surface-treated with hexamethyldisilazane, primary particle size: 0.02 μm) was mixed with 100 parts by weight of the base toner using a Henschel mixer as an external additive. Was carried out to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under the low gloss image condition is 3.4, which is low, but the gloss starts to appear slightly because the maximum peak in the GPC molecular weight distribution of the resin A is as low as 5,000. The glossiness of the first sheet under high gloss image conditions with a linear speed of 速 is 3
The gloss of the tenth sheet was 3.3, and a clear high-gloss image was stably obtained at 29.1. Although the minimum fixing temperature was as good as 130 ° C., the toner was slightly loosened in a heat preservation test, but weak fusion of the toners was started. In the heat storage test, the toner was stored at 45 ° C. for 8 hours.

Example 3 As resin A, the DSC peak temperature of terephthalic acid, fumaric acid, trimellitic anhydride, PO adduct of bisphenol A and EO adduct of bisphenol A was 75 ° C.
A polyester resin having a maximum peak in the GPC molecular weight distribution of 20,000 and a component having a molecular weight of 1 × 10 ⁵ or more of 11% by weight was obtained.

With respect to 85 parts by weight of this resin, 15 parts by weight of resin B was a polystyrene resin having a DSC peak temperature of 85 ° C., a maximum peak in the GPC molecular weight distribution of 4000, and a component having a molecular weight of 1 × 10 ⁵ or more and 0% by weight. Parts, 3 parts by weight of a polyethylene wax having a melting point of 106 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge control agent), and 3 parts by weight of a copper phthalocyanine blue pigment (C.Ipigment Blue 15), followed by twin-screw extrusion. After cooling, the mixture was cooled, pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm.
To 100 parts by weight of the base toner, 0.5 part by weight of hydrophobic silica (surface-treated with hexamethyldisilazane, primary particle diameter: 0.02 μm) as an external additive was mixed with a Henschel mixer. Was carried out to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under low gloss image conditions is 1.6 and there is almost no gloss.
The glossiness of the first sheet under the high gloss image condition with the linear velocity reduced to 1/2 was 21.1, and the glossiness of the tenth sheet was 19.3, and a clear high gloss image was stably obtained. Fixing minimum temperature is 145
The temperature was slightly high.

Example 4 As the resin A, 90% of the polyester resin used in Example 1 was used.
Parts by weight and a hydrogenated petroleum resin having a DSC peak temperature of 87 ° C., a molecular weight peak temperature of 1100, and a component amount of 1 × 10 ⁵ or more being 0 parts by weight as the resin B (hydrogenation ratio about 75%)
10 parts by weight, 3 parts by weight of a polyethylene wax having a melting point of 106 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge controlling agent), and copper phthalocyanine blue pigment (C. Ipigme).
After mixing 3 parts by weight of nt Blue 15), the mixture was kneaded with a twin screw extruder, cooled, pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm. Hydrophobic silica (surface-treated with hexamethyldisilazane, primary particle diameter: 0.02 μm) was used as an external additive with respect to 100 parts by weight of the base toner.
0.5 parts by weight was mixed with a Henschel mixer to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under low gloss image conditions is almost 1.9, and there is almost no gloss.
The glossiness of the first sheet under the high gloss image condition where the linear velocity was halved was 34.5, and the glossiness of the tenth sheet was 30.8, which is slightly higher than that of Example 1 and a clear image. Was obtained stably. The minimum fixing temperature was 135 ° C., which was the same as that of Example 1 and showed satisfactory fixing performance.

Example 5 As resin A, the DSC peak temperature of terephthalic acid, succinic acid derivative, trimellitic anhydride, bisphenol A EO adduct, bisphenol A EO adduct was 6
At 8 ° C., the maximum peak in the GPC molecular weight distribution is 1200.
A polyester resin having 0 and a component having a molecular weight of 1 × 10 ⁵ or more was 3% by weight.

The resin B had a DSC peak temperature of 87 ° C. and a molecular weight peak temperature of 110 parts by weight with respect to 97 parts by weight of the resin.
0, ³ parts by weight of a hydrogenated petroleum resin having a molecular weight of 1 × 10 ⁵ or more and 0 parts by weight (hydrogenation ratio: about 75%), and a melting point of 10 parts.
3 parts by weight of polyethylene wax at 6 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge controlling agent), and 3 parts by weight of copper phthalocyanine blue pigment (C.Igmentment Blue 15) are mixed, and then kneaded with a twin screw extruder. After cooling, the mixture was pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm.

Hydrophobic silica (surface-treated with hexamethyldisilazane, primary particle diameter: 0.02 μm) was used as an external additive with respect to 100 parts by weight of the base toner.
0.5 parts by weight was mixed with a Henschel mixer to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under low gloss image conditions is 3.8, which is low gloss, but the gloss starts to appear slightly because the molecular weight of resin A is 1 × 10 ⁵
This is because the amounts of the above components are as low as 3% by weight. Linear speed 1
The glossiness of the first sheet under high gloss image conditions of / 2 is 24.
3, a clear high-gloss image was obtained, but the gloss was slightly lower than that in Example 2 in which gloss began to appear slightly under low-gloss image conditions. This is because the resin B component is as small as 3 parts by weight. The glossiness of the tenth sheet was stable at 21.6, and the minimum fixing temperature was 135 ° C., indicating satisfactory fixing performance.

Example 6 The resin A had a DSC peak temperature of 6 consisting of terephthalic acid, a succinic acid derivative, trimellitic anhydride, an EO adduct of bisphenol A, and an EO adduct of bisphenol A.
2 ° C., the maximum peak in the GPC molecular weight distribution is 1000
A polyester resin having 0 and the amount of components having a molecular weight of 1 × 10 ⁵ or more was 20% by weight was obtained.

The resin B had a DSC peak temperature of 87 ° C. and a molecular weight peak temperature of 110 parts by weight based on 65 parts by weight of the resin.
0, 35 parts by weight of a hydrogenated petroleum resin having a molecular weight of 1 × 10 ⁵ or more and 0 parts by weight (hydrogenation ratio: about 75%), and a melting point of 1 part.
After mixing 3 parts by weight of polyethylene wax at 06 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge control agent), and 3 parts by weight of copper phthalocyanine blue pigment (C.Ipigment Blue 15), the mixture is kneaded with a twin screw extruder. Crushed after cooling,
After classification, a base toner having a volume average particle size of about 8 μm was obtained. For 100 parts by weight of the base toner, as an external additive,
0.5 parts by weight of hydrophobic silica (surface treated with hexamethyldisilazane, primary particle diameter: 0.02 μm) was mixed with a Henschel mixer to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under low gloss image conditions is 2.1 and low gloss, and the glossiness of the first sheet under high gloss image conditions with a linear speed of １ ／ is 4
The gloss of the tenth sheet was 1.7, and a clear, high-gloss image was stably obtained. The minimum fixing temperature was 135 ° C., indicating a satisfactory fixing property.

Example 7 As resin A, the DSC peak temperature of terephthalic acid, a succinic acid derivative, trimellitic anhydride, an EO adduct of bisphenol A, and an EO adduct of bisphenol A was 6
At 6 ° C., the maximum peak in the GPC molecular weight distribution was 1800.
0, 65 parts by weight of a polyester resin containing 17% by weight of a component having a molecular weight of 1 × 10 ⁵ or more and a DSC peak temperature of 7%.
0 ° C., the maximum peak in the GPC molecular weight distribution is 1000
0, a mixture of 25 parts by weight of a polyol resin in which the amount of a component having a molecular weight of 1 × 10 ⁵ or more was 2% by weight was prepared.

The resin B had a DSC peak temperature of 87 ° C. and a molecular weight peak temperature of 100 parts by weight based on 90 parts by weight of the resin.
0, 10 parts by weight of a hydrogenated petroleum resin having a molecular weight of 1 × 10 ⁵ or more and 0 parts by weight (hydrogenation ratio: about 95%), and a melting point of 8
After mixing 5 parts by weight of carnauba wax at 3 ° C., 2 parts by weight of a zinc salt of a salicylic acid derivative (charge control agent), and 3 parts by weight of copper phthalocyanine blue pigment (C. Ipigment Blue 15), the mixture was mixed with a twin screw extruder. The mixture was kneaded, cooled, pulverized and classified to obtain a base toner having a volume average particle size of about 8 μm. To 100 parts by weight of these base toners, hydrophobic silica (surface-treated with hexamethyldisilazane, 1
0.5 parts by weight (secondary particle diameter: 0.02 μm) was mixed with a Henschel mixer to obtain a cyan toner.

Using this toner, a two-component developer was prepared in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The glossiness under low gloss image conditions is 2.0, which is low gloss, and the glossiness of the first sheet under high gloss image conditions with a linear speed of は is 3
The gloss of the tenth sheet was 5.2, and a clear high gloss image was stably obtained. The minimum fixing temperature was 135 ° C., indicating a satisfactory fixing property.

Comparative Example 1 In Example 1, no resin B was used, and a resin A component was used.
DSC peak temperature of terephthalic acid, fumaric acid, trimellitic anhydride, PO adduct of bisphenol A, EO adduct of bisphenol A is 66 ° C., the maximum peak in GPC molecular weight distribution is 11000, and the molecular weight is 1 × 10 ^5.
Polyester resin 1 containing 14% by weight of the above components
A toner and a developer were prepared in the same manner as in Example 1 except that only 00 parts by weight was used, and the evaluation was performed in the same manner as in Example 1.

The glossiness under low gloss image conditions is 1.5, which is almost no gloss, and the glossiness of the first sheet under high gloss image conditions with a linear speed of あ り is 8.3, which is the tenth sheet. Has a gloss value of 6.8, and a high gloss image was not obtained. The minimum fixing temperature was 135 ° C., indicating a satisfactory fixing property.

Comparative Example 2 Resin A was used without resin B, and terephthalic acid, fumaric acid, PO adduct of bisphenol A, bisphenol A
DSC peak temperature of EO adduct of 67 ° C, GP
A toner and a developer were prepared in the same manner as in Example 1, except that only 100 parts by weight of a polyester resin having a maximum peak of 10,000 in the C molecular weight distribution and 0% by weight of a component having a molecular weight of 1 × 10 ⁵ or more was used. Evaluation was performed in the same manner as in 1.

The glossiness under low gloss image conditions was 13.6, and no low gloss image was obtained. The glossiness of the first sheet under the high gloss image condition where the linear velocity was halved was 45.9, which was 1
The gloss of the zeroth sheet was 32.4, which was a large decrease in gloss during continuous fixing. The minimum fixing temperature was 135 ° C., indicating a satisfactory fixing property.

Comparative Example 3 A toner and a developer were prepared in the same manner as in Example 6 except that only 60 parts by weight of the resin A used in Example 6 and 40 parts by weight of the resin B used in Example 6 were used. Evaluation was performed in the same manner as described above.

The gloss under the low gloss image condition is 2.2, which is a relatively low gloss, and the gloss under the high gloss image condition in which the linear velocity is halved.
The glossiness of the first sheet is 11.9, and the glossiness of the tenth sheet is 3
8.5. The reason why the glossiness under the high gloss condition was low was that offset was caused. In the tenth continuous sheet, the fixing roller temperature was lowered, and the offset was reduced, so that the glossiness was high. The minimum fixing temperature was 135 ° C., indicating a satisfactory fixing property.

[0057]

According to the first aspect of the present invention, the color toner has an endothermic peak temperature in DSC of 55 to 7 as a binder resin.
In the range of 5 ° C., the maximum peak in the molecular weight distribution by GPC is the endothermic peak temperature in resin A and DSC in which the molecular weight is 5,000 to 20,000 and the component having a molecular weight of 1 × 10 ⁵ or more is 3 to 20% by weight. Is at least 10 ° C. higher than the endothermic peak temperature in DSC of resin A, the maximum peak in the molecular weight distribution by GPC is present at a molecular weight of 500 to 5000, and the molecular weight is 1
By containing resin B having no more than × 10 ⁵ component, stable low gloss while giving sufficient fixability to the fixing method that changes the glossiness of the image by changing the amount of heat and pressure applied to the toner. An image was obtained, and a stable high gloss image could be obtained without largely changing fixing conditions.

In the color toner of the second aspect, since the resin B of the first aspect is a hydrogenated petroleum resin, a low gloss image and a high gloss image can be obtained stably and responsively.

In the color toner according to the third aspect, the ratio of the resin B to all binder resins in the toner is 3 to 35.
By setting the percentage by weight, the effect of the present invention can be ensured, and the margin for the offset phenomenon can be improved.

 ──────────────────────────────────────────────────続 き Continued from the front page (72) Inventor Hiroyuki Fushimi 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Company (72) Inventor Keiko Shiraishi 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh F term (reference) 2H005 AA01 AA06 AA21 CA15 CA21 DA04 EA03 EA06 EA07 FB01

Claims (3)

[Claims] 1. A binder resin comprising at least a binder and a colorant, wherein the binder resin has an endothermic peak temperature in the range of 55 to 75 ° C. in DSC and a maximum peak in a molecular weight distribution by GPC of 5,000 to 20,000.
And 3 to 2 components having a molecular weight of 1 × 10 ⁵ or more.
Resin A present at 0% by weight, the endothermic peak temperature in DSC is at least 10 ° C. higher than the endothermic peak temperature in DSC of resin A, the maximum peak in the molecular weight distribution by GPC is in the range of 500 to 5000, and the molecular weight is A color toner for developing electrostatic images, comprising a resin B having no more than 1 × 10 ⁵ components. 2. The color toner for developing an electrostatic image according to claim 1, wherein the resin B is a hydrogenated petroleum resin. 3. The color toner for developing electrostatic images according to claim 1, wherein the ratio of the resin B to the total binder resin in the toner is 3 to 35% by weight.