JP2000292987A - Positive polarity toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a positive polarity toner which does not cause contamination in the base of a nonpicture part or splashing of the toner even when a large number of sheets are copied and which gives a high image density by incorporating a binder resin and a specified quaternary ammonium salt group-contg. copolymer as a charge controlling agent. SOLUTION: This toner contains a binder resin and a quaternary ammonium salt group-contg. copolymer as a charge controlling agent. This copolymer consists of 97.0 to 99.5 wt.% of recurring units expressed by formula I and 3.0 to 0.5 wt.% of recurring units expressed by formula II and has 5000 to 25000 weight average mol.wt. and 1.0×104 to 5.0×104 melt viscosity at 100 deg.C. In formula I, R1 is hydrogen atom or methyl group. In formula II, R2 is hydrogen atom or methyl group, R3 is an alkylene group, and each of R4 to R6 is an alkyl group. As for the binder resin, it is effective to use a polyester resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry toner for developing an electrostatic latent image in electrophotography and the like, and more particularly to a positive dry toner.

[0002]

2. Description of the Related Art A method of developing an electrostatic latent image formed by electrophotography is roughly classified into a liquid developing method using a developer in which various pigments and dyes are finely dispersed in an insulating organic liquid. And a dry development method using a toner in which a coloring agent such as carbon black is dispersed in a natural or synthetic resin, such as a cascade method, a magnetic brush method, or a powder cloud method.

In the dry developing method, when toner particles charged by friction with a charging member such as a carrier, a blade, or a sleeve come close to an electrostatic latent image, the toner particles are attracted by an electric field formed by the electrostatic latent image. The electrostatic latent image is visualized by being attracted and attached to the electrostatic latent image by a force. Therefore, it is indispensable that the toner used for these components is quickly and uniformly charged by friction with the charging member. Other properties required for the toner include fixability, fluidity, environmental stability,
Examples include mechanical strength and pulverizability. As known, the dry toner used in these methods contains a binder resin, a colorant, and a charge control agent as main components, and optionally contains additives such as a release agent and an inorganic fine powder. It is.

Conventional charge control agents for imparting positive polarity include nigrosine dyes described in JP-B-41-2427 and US Pat. No. 3,565,654.
The quaternary ammonium salts described in JP-A-60-169857 and the like, and resin-type charge control agents include JP-A-5-297641 and JP-A-7-209908.
And Japanese Patent Application Laid-Open No. 7-225496. Japanese Patent Application Laid-Open No. 63-60458 discloses a novel quaternary ammonium salt group-containing copolymer.

[0005]

However, these conventional positive charge control agents have a drawback that the charge amount of the toner greatly varies depending on the use environment. Also,
In recent years, it has been difficult to uniformly disperse the toner in a toner having a small particle size for high image quality, and the conventional charge control agent has caused problems such as background contamination of a non-image portion and toner scattering caused by uneven dispersion. Was.

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and a positive polarity toner having a high image density without causing the above-described background stain or toner scattering in a non-image area even when a large number of copies are made. The purpose is to gain.

[0007]

According to the present invention, first, as a binder resin and a charge controlling agent, 97.0 to 99.5% by weight of a repeating unit represented by the following general formula (1): It consists of 3.0 to 0.5% by weight of the repeating unit represented by the formula (2), and has a weight average molecular weight of 5,000 to 25.
A quaternary ammonium salt group-containing copolymer having a melt viscosity at 100 ° C. of 1.0 × 10 ^{4 to} 5.0 × 10 ^4. Is provided.

[0008]

Embedded image In the formula, R ₁ represents a hydrogen atom or a methyl group.

[0009]

Embedded image In the formula, R ₂ represents a hydrogen atom or a methyl group, R ₃ represents an alkylene group, and R ₄ , R ₅ and R ₆ represent an alkyl group.

Second, in the positive toner described in the first aspect, the melt viscosity at 100 ° C. of the binder resin is defined as ηR, and the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is defined as ηCCA. Wherein the relationship between the melt viscosities is represented by the following formula.

[0011]

3 <ηR / ηCCA <10 Thirdly, in the positive toner described in the first or second aspect, the Tg (shoulder value) of the binder resin is defined as TgR.
And the Tg of the quaternary ammonium salt group-containing copolymer
When (peak value) is defined as TgCCA, a positive polarity toner is provided in which the relationship between the Tg is represented by the following formula.

[0012]

0.8 <TgR / TgCCA <1.0 Fourth, in the first, second or third positive toner, the binder resin is a polyester resin. Is provided.

Fifth, in the positive toner according to the first, second or third aspect, the binder resin is a combination of a polyester resin and a styrene-acrylic copolymer. A toner is provided.

Sixth, in the positive toner described in the fifth aspect, the melt viscosity of the polyester resin at 100 ° C. is ηPE, the melt viscosity of the styrene-acrylic copolymer at 100 ° C. is ηSt, When the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is ηCCA, a positive polarity toner characterized in that the relationship between the melt viscosities is represented by the following formula is provided.

[0015]

(7) ηCCA <ηSt <ηPE

Seventh, in the positive polarity toner described in the fifth aspect, the Tg (shoulder value) of the polyester resin is TgPE, and the Tg of the styrene-acrylic copolymer is TgPE.
Is defined as TgSt and Tg of the quaternary ammonium salt group-containing copolymer is defined as TgCCA.

[0017]

## EQU8 ## TgPE <TgSt ≦ TgCCA

Eighth, in the positive toner according to the fifth, sixth or seventh aspect, the styrene-acrylic copolymer is a styrene-butyl acrylate copolymer. Is provided.

Ninth, in the first, second, third, sixth or seventh positive toner, the quaternary ammonium salt group-containing copolymer has a particle size of 2.0 mm or less. A positive polarity toner is provided.

Tenth, in the positive toner described in the first, second, third, sixth or seventh, the binder resin and the quaternary ammonium base-containing copolymer each have a particle size of 2 0.0 mm or less is provided.

Hereinafter, the present invention will be described in detail. As described above, the present invention provides, as a binder resin and a charge controlling agent, 97.0 to 99.5% by weight of the repeating unit represented by the above general formula (1) and 3.0 repeating units represented by the general formula (2). ~
0.5% by weight and having a weight average molecular weight of 500
The present invention relates to a positive polarity toner containing a quaternary ammonium salt group-containing copolymer having a melt viscosity at 100 ° C. of 1.0 × 10 ^{4 to} 5.0 × 10 ⁴ . According to such a configuration, the above-described background stain and toner scattering are suppressed, and a positive polarity toner having a high image density can be obtained.

More specifically, the quaternary ammonium salt group-containing copolymer used as a charge control agent has a chargeability of the toner when the repeating unit represented by the above general formula (2) is less than 0.5% by weight. Is less effective in imparting
The charge amount of the toner is low, the rise of the charge is also deteriorated, and the background stain and toner scattering are likely to occur. On the other hand, when the repeating unit is more than 3.0% by weight, the charge amount of the toner is increased, and the image density is reduced. By reducing the amount of the quaternary ammonium salt group-containing copolymer, the charge amount can be adjusted to an appropriate value. However, since the amount is small, it is difficult to uniformly disperse the toner in the toner. As a result, the charge rising property deteriorates, and the background stain and toner scattering easily occur. The addition amount of the quaternary ammonium base-containing copolymer is 0.1 to 5.0 parts by weight, preferably 0.5 to 3.0 parts by weight.

The weight average molecular weight of the quaternary ammonium salt group-containing copolymer is preferably in the range of 5,000 to 25,000. If it is smaller than 5000, the toner is excessively pulverized in the developing device, or the storage stability of the toner is deteriorated. on the other hand,
If it is larger than 25,000, it is difficult to uniformly disperse the toner in the toner, the charge rising property is deteriorated, and the background stain and toner scattering are likely to occur.

The quaternary ammonium salt group-containing copolymer has a melt viscosity at 100 ° C. of 1.0 × 10 ⁴ to 1.0 × 10 ⁴ .
It is important that the range be 5.0 × 10 ⁴ . When the melt viscosity is smaller than 1.0 × 10 ⁴ , the fourth
The viscosity of the quaternary ammonium base-containing copolymer becomes too low, so that the copolymer cannot be uniformly dispersed in the binder resin, the charge rising property is deteriorated, and the background stain and toner scattering are likely to occur. On the other hand, if the melt viscosity is larger than 5.0 × 10 ⁴ , the melt viscosity of the quaternary ammonium salt group-containing copolymer becomes too high at the time of kneading the toner, so that the copolymer cannot be uniformly dispersed in the binder resin. The charge rising property is deteriorated, and background stain and toner scattering are likely to occur. The melt viscosity is a value measured with a flow tester CFT-500C (manufactured by Shimadzu Corporation), and the measurement conditions were as follows: extrusion pressure: 1.9612 M
Pa, heating rate: 6 ° C./min, die diameter: 1.0 mm,
Die length: measured under a condition of 1.0 mm.
The melt viscosity η is determined by the following equation.

[0025]

[Equation 9] Melt viscosity η = τ / γ = πD ⁴ P / 128LQ where P: extrusion pressure (Pa) D: die diameter (mm) L: die length (mm) Q = X / 10 × A / t t: Measurement time (s) X: Movement amount of the piston with respect to the measurement time t (mm) A: Cross-sectional area of the piston (cm ² )

When the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is ηCCA and the melt viscosity of the binder resin at 100 ° C. is ηR, the relationship between the melt viscosities is represented by the following formula. It is important to be in range.

[0027]

2 <ηR / ηCCA <10 When ηR / ηCCA is smaller than 2, the compatibility at the time of kneading the binder resin and the quaternary ammonium base-containing copolymer is deteriorated. On the other hand, if it is larger than 10, the compatibility deteriorates, uniform dispersion cannot be performed, and the charging startability deteriorates, and the background stain and toner scattering easily occur.

In the present invention, when the Tg (shoulder value) of the binder resin is TgR and the Tg (peak value) of the quaternary ammonium salt group-containing copolymer is TgCCA, the relationship between these Tg is shown by the following formula. It is important to be in the range

[0029]

8 <TgR / TgCCA <1.0 In the above formula, if TgR / TgCCA is smaller than 0.8 or larger than 1.0, the compatibility becomes poor and uniform dispersion cannot be achieved. The charge rising property is deteriorated, and background stain and toner scattering are likely to occur.

In the present invention, it is useful to use a polyester resin as the binder resin. The polyester resin is not only extremely useful as a low-temperature fixing resin, but also has extremely good compatibility with the quaternary ammonium base-containing copolymer used in the present invention, and enables uniform dispersion.
The polyester resin used in the present invention is obtained by condensation polymerization of an alcohol and a carboxylic acid. Examples of the alcohol used include glycols such as ethylene glycol, dithylene glycol, triethylene glycol, and propylene glycol; etherified bisphenols such as 1,4-bis (hydroxymeth) cyclohexane and bisphenol A; and other divalent alcohols. And polyhydric alcohol monomers having three or more alcohols. Further, as the carboxylic acid, for example, maleic acid,
Fumaric acid, phthalic acid, isophthalic acid, terephthalic acid,
Divalent organic acid monomers such as succinic acid and malonic acid;
4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-cyclohexanetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,
2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methylenecarboxypropane, 1,2,7,
Examples thereof include trivalent or higher polyvalent carboxylic acid monomers such as 8-octanetetracarboxylic acid. Polyester resins are inherently easily charged to a negative polarity (especially when maleic acid, fumaric acid, etc. are used), and when used for positive polarity toners, it is particularly important to uniformly disperse the charge control agent. The quaternary ammonium salt group-containing copolymer used in the invention is particularly useful. Further, in the present invention, it is important to use a polyester resin and a styrene-acrylic copolymer together as a binder resin.

Further, the Tg (shoulder value) of the polyester resin is TgPE, the Tg (shoulder value) of the styrene-acrylic copolymer is TgSt, and the Tg (peak value) of the quaternary ammonium group-containing copolymer is TgCCA. It is important that the relationship between the Tg's is within the range shown by the following formula.

[0032]

TgPE <TgSt ≦ TgCCA When the Tg of the styrene-acrylic copolymer is lower than the Tg of the polyester resin, the storage stability of the toner against heat (heat-resistant storage stability) is deteriorated, and the styrene-acrylic copolymer is deteriorated. Is the Tg of the quaternary ammonium salt group-containing copolymer
If it is higher, the low-temperature fixability of the toner may be impaired.

Further, in the present invention, the melt viscosity of the polyester resin at 100 ° C. is ηPE, and the melt viscosity of the styrene-acrylic copolymer at 100 ° C. is ηS
t, when the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is defined as ηCCA, it is important that the relation between the melt viscosities is within the range shown by the following formula.

[0034]

１３CCA <ηSt <ηPE Polyester resin is generally known to have extremely poor pulverizability in producing toner by pulverization. Styrene-acrylic copolymers are more excellent in pulverizability than polyester resins, and therefore, by using them in combination, it is possible to increase toner productivity. However, if the melt viscosity and Tg of the styrene-acrylic copolymer are not controlled within the range of the above formula, a problem may occur. When the melt viscosity of the styrene-acrylic copolymer is lower than the melt viscosity of the quaternary ammonium salt group-containing copolymer, the compatibility of the quaternary ammonium salt group-containing copolymer with the polyester resin becomes poor, and the polyester resin If the melt viscosity is higher than the above, the compatibility between the styrene-acrylic copolymer and the quaternary ammonium salt group-containing copolymer becomes poor, uniform dispersion cannot be performed, the charging startability deteriorates, background stains and toner scattering occur. Is more likely to occur. If the Tg of the styrene-acrylic copolymer is higher than the Tg of the quaternary ammonium salt group-containing copolymer, the compatibility of the quaternary ammonium salt group-containing copolymer with the polyester resin becomes poor, and the melting of the polyester resin becomes poor. If the viscosity is lower than the above, the compatibility between the styrene-acrylic copolymer and the quaternary ammonium salt group-containing copolymer becomes poor, uniform dispersion cannot be performed, and the charge start-up property deteriorates, and background stain and toner scattering occur. Easier to do.

As the styrene-acrylic copolymer used in the present invention, any conventionally known resin can be used, and a styrene monomer and an acrylate or methacrylate are copolymerized or partially crosslinked. It is obtained. Examples of the styrene monomer include styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, 2,4-dimethylstyrene, and 3,4-dimethylstyrene. In addition, as the acrylate, ethyl acrylate, methyl acrylate,
Propyl acrylate, n-butyl acrylate, isobutyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, methacrylic acid, ethyl methacrylate, methyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, methacryl Dodecyl acid, 2-ethylhexyl methacrylate and the like. The amount of the styrene-acrylic copolymer used is 0 to
70 parts by weight, preferably 0 to 50 parts by weight. The measurement of Tg uses DSC-200 manufactured by Seiko Denshi Kogyo Co., Ltd.
For a polyester resin and a styrene-acrylic copolymer, the peak rising temperature (shoulder value) of the DSC curve is read, and for the quaternary ammonium base-containing copolymer, the peak temperature (peak value) is read. The styrene-acrylic copolymer used in the present invention is particularly preferably a styrene-butyl acrylate copolymer. The quaternary ammonium salt group-containing copolymer used in the present invention has excellent compatibility with styrene-acrylic copolymers, particularly, styrene-butyl acrylate copolymer, and therefore has a uniform dispersibility. Excellent.

It is important that the quaternary ammonium salt group-containing copolymer used in the present invention has a particle size of 2.0 mm or less. If it is larger than 2.0 mm, the dispersion in the binder resin will be poor. This is particularly uniaxial,
It becomes remarkable when the kneading time is short, such as a continuous kneader such as a twin-screw extruder, and the charge rising property is deteriorated.
Background stains and toner scattering tend to occur. In the present invention, it is important that the polyester resin and the styrene-acrylic acid-based copolymer other than the quaternary ammonium base-containing copolymer also have a particle size of 2.0 mm or less. By setting the particle size of the quaternary ammonium base-containing copolymer, polyester resin, and styrene-acrylic acid-based copolymer to 2.0 mm or less, the dispersion of the quaternary ammonium base-containing copolymer in the toner is improved. Thus, uniform dispersion is possible in each of the polyester resin and the styrene-acrylic acid-based copolymer, and the rising property of charging, the background stain, and the scattering property of the toner are improved.

Specific examples of the quaternary ammonium salt group-containing copolymer usable in the present invention include those having the following structural formulas.

[0038]

(Compound Example 1)

[0039]

(Compound Example 2)

In the present invention, resins other than polyester resins and styrene-acrylic copolymers can be used. As other resins used in the present invention, conventionally known resins can be used. For example, vinyl chloride resin, rosin-modified maleic resin, phenol resin, polyethylene resin, polypropylene resin, petroleum resin, polyurethane resin, epoxy resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin, polyvinyl butyrate resin, etc. No. Two or more of these resins may be used in combination. Also, the method for producing these resins is not particularly limited, and any of bulk polymerization, solution polymerization, emulsion polymerization, and suspension polymerization can be used.

As the colorant used in the present invention, all pigments and dyes conventionally used as colorants for toner are applied. Specifically, carbon black,
Lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, calco oil blue, Dupont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, phthalocyanine green, hansa yellow, rhodamine 6C lake, chrome yellow, quinacridone, benzidine yellow, malachite green,
Malachite green hexaite, oil black, azo oil black, rose bengal, monoazo dye,
Disazo dyes and pigments, trisazo dyes and the like can be mentioned. The amount of the colorant used is 1 to 10 parts by weight, preferably 3 parts by weight.
７7 parts by weight.

Further, the toner of the present invention may contain a releasing agent such as wax if necessary. Examples of the wax component include polyolefin wax such as polyethylene wax and polypropylene wax, and natural wax such as carnauba wax, candelilla wax and rice wax. The amount of the wax used is 0.5 to 10 parts by weight, preferably 2 to 7 parts by weight.

The method for producing the toner of the present invention may be a conventionally known method, including a binder resin (polyester resin, styrene-acrylic copolymer, etc.), a quaternary ammonium base-containing copolymer, a colorant, Depending on the material such as a release agent is mixed using a mixer or the like, and kneaded using a kneader such as a hot roll or an extruder, then cooled and solidified, and then pulverized by a pulverizer such as a jet mill. Obtained by classification.

Other additives can be added to the toner as required. Examples of the additive include silica, aluminum oxides, and titanium oxides. When the main purpose is to impart high fluidity, the average primary particle diameter can be appropriately selected from those having a hydrophobized silica or rutile type fine particle titanium oxide in the range of 0.001 to 1 μm. Silica or titania is preferred, and is usually used at a ratio of 0.1 to 5% by weight, preferably 0.2 to 2% by weight.

For example, when the toner of the present invention is used as a two-component dry toner, the carrier used as a mixture may be a glass, iron, ferrite, nickel, zircon, silica or the like having a particle diameter of 30 as a main component. ~ 1000 μm
It is possible to use a powder of a suitable degree or a powder coated with a styrene-acrylic copolymer, a silicone resin, a polyamide resin, a polyvinylidene fluoride resin, or the like as a core agent.

[0046]

[Example 1]

 (Toner formulation) Styrene resin (particle size: 3 to 7 mm, ηR: 3.0 × 10^Four, Tg: 67 ° C) 85 parts Carbon black (manufactured by Mitsubishi Kasei Co., # 44) 10 parts Polypropylene (manufactured by Sanyo Kasei Co., Ltd., Viscol 550P) 3 parts Quaternary ammonium base-containing copolymer (Compound Example 1) (Particle size) : 3 to 7 mm, ηCCA: 4.5 × 10^Four, Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After crushing and classifying to a weight average particle size of 9.0 μm,
Mix 0.5 parts of titanium oxide fine powder using a well mixer
Thus, a positive polarity toner was obtained. This toner and an average particle diameter of 80 μm
m silicone ferrite particles coated with silicone resin
Carrier, prepare a developer with a toner concentration of 3.0 parts.
10 with an analog copier (Spirio 7000)
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
10,000, 100,000 sheets, using the following measurement method,
-The scattering and the image density were measured. Evaluation results of each characteristic
Is shown in Tables 1 to 3. "Measuring method"Background dirt  Non-image area (background area) on photoreceptor before transfer to transfer paper
Transfers the toner adhering to the tape to the Macbeth density
Measure the concentration with a meter. The larger the value, the more the background
That is bad.Toner scattering  Paste the tape on the upper part of the developing unit and
And transfer the toner attached to the unit to the tape
Then, the concentration is measured with a Macbeth densitometer. This value
It can be said that the larger the value, the worse the toner scattering.Image density  Copy a copy of the original density 1.6 φ30 image
The density is measured with a densitometer, and the average value at five points is defined as the image density.

Comparative Example 1 (Toner formulation) Styrene resin (particle size: 3 to 7 mm, ηR: 3.0 × 10 ⁴ , Tg: 67 ° C.) 85 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (manufactured by Sanyo Kasei Co., Ltd., Viscol 550P) 3 part: quaternary ammonium base-containing copolymer (composition is the same as in compound example 1) (particle size: 3 to 7 mm, ηCCA: 9.0 × 10 ³ , Tg: 62 ° C) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Comparative Example 2 (Toner Formulation) Styrene resin (particle size: 3 to 7 mm, ηR: 3.0 × 10 ⁴ , Tg: 67 ° C.) 85 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (manufactured by Sanyo Chemical Co., Ltd., Viscol 550P) 3 part: quaternary ammonium base-containing copolymer (the composition is the same as in compound example 1) (particle size: 3 to 7 mm, ηCCA: 8.5 × 10 ⁴ , Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 2 (Toner formulation) Epoxy resin (particle size: 3 to 7 mm, ηR: 1.4 × 10 ⁵ , Tg: 65 ° C.) 84 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (Viscol 550P, manufactured by Sanyo Kasei Co., Ltd.) 3 part: quaternary ammonium base-containing copolymer (Compound Example 1) (particle size: 3 to 7 mm, ηCCA: 4.5 × 10 ⁴ , Tg: 64 ° C.) Part kneading using a twin-screw extruder according to the above prescription,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 3 (Toner formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 7.0 × 10 ⁴ , Tg: 62 ° C.) 85 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd.) 3 part: quaternary ammonium base-containing copolymer (Compound Example 2) (particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 Part kneading using a twin-screw extruder according to the above prescription,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 4 (Toner formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 9.5 × 10 ⁴ , Tg: 65 ° C.) 85 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd.) 3 part: quaternary ammonium base-containing copolymer (Compound Example 2) (particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 Part kneading using a twin-screw extruder according to the above prescription,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 5 (Toner Formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 9.5 × 10 ⁴ , Tg: 65 ° C.) 50 parts Styrene-methyl acrylate copolymer (particle size: 3) ７7 mm, ηSt: 5.0 × 10 ⁴ , Tg: 62 ° C.) 35 parts Carbon black (manufactured by Mitsubishi Kasei Co., # 44) 10 parts Polypropylene (manufactured by Sanyo Chemical Co., Viscol 550P) 3 parts Quaternary ammonium base-containing Copolymer (Compound Example 2) (Particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 6 (Toner formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 7.0 × 10 ⁴ , Tg: 62 ° C.) 45 parts Styrene-methyl acrylate copolymer (particle size: 3 ７St: 4.0 × 10 ⁴ , Tg: 61 ° C.) 40 parts Carbon black (manufactured by Mitsubishi Kasei Co., # 44) 10 parts Polypropylene (manufactured by Sanyo Chemical Co., Viscol 550P) 3 parts Quaternary ammonium base-containing Copolymer (Compound Example 2) (Particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m, and the mixture was prepared using a Ricoh analog copying machine (Spirion 7000).
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 7 (Toner formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 3.5 × 10 ⁴ , Tg: 60 ° C.) 45 parts Styrene-methyl acrylate copolymer (particle size: 3 ７St: 4.0 × 10 ⁴ , Tg: 63 ° C.) 40 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 parts Polypropylene (manufactured by Sanyo Chemical Co., Viscol 550P) 3 parts Quaternary ammonium base-containing Copolymer (Compound Example 2) (Particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 8 (Toner formulation) Polyester resin (particle size: 3 to 7 mm, ηPE: 7.0 × 10 ⁴ , Tg: 62 ° C.) 45 parts Styrene-butyl acrylate copolymer (particle size: 3) ７St: 4.0 × 10 ⁴ , Tg: 63 ° C.) 40 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 parts Polypropylene (manufactured by Sanyo Chemical Co., Viscol 550P) 3 parts Quaternary ammonium base-containing Copolymer (Compound Example 2) (Particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 parts Kneading using a twin-screw extruder according to the above formulation,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m, and the mixture was prepared using a Ricoh analog copying machine (Spirion 7000).
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 9 Toner Formulation Polyester resin (particle size: 3 to 7 mm, ηPE: 7.0 × 10 ⁴ , Tg: 62 ° C.) 85 parts Carbon black (manufactured by Mitsubishi Kasei Corporation, # 44) 10 Part: polypropylene (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd.) 3 part: quaternary ammonium base-containing copolymer (Compound Example 2) (particle size: 3 to 7 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 Part kneading using a twin-screw extruder according to the above prescription,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

Example 10 (Toner formulation) Polyester resin (particle size: 0.1 to 2.0 mm, ηPE: 7.0 × 10 ⁴ , Tg: 62 ° C.) 45 parts Styrene-methyl acrylate copolymer ( Particle size: 0.1 to 2.0 mm, ηSt: 4.0 × 10 ⁴ , Tg: 63 ° C.) 40 parts Carbon black (Mitsubishi Kasei Co., # 44) 10 parts Polypropylene (Sanyo Chemical Co., Viscol 550P) 3 parts Copolymer containing quaternary ammonium base (Compound Example 2) (Particle size: 0.1 to 2.0 mm, ηCCA: 2.0 × 10 ⁴ , Tg: 64 ° C.) 2 parts Biaxial extruded according to the above formulation Knead using a ruder,
After pulverizing and classifying to a weight average particle size of 9.0 μm, 0.5 parts of titanium oxide fine powder was mixed using a Henschel mixer to obtain a positive polarity toner. This toner and an average particle diameter of 80 μm
A toner having a toner concentration of 3.0 parts was prepared using a carrier obtained by coating a silicone resin on spherical ferrite particles having a particle size of m.
10,000 copies were made. On the way, 10,000, 30,000, 50,000, 7
On 100,000 and 100,000 sheets, background stain, toner scattering and image density were measured by the above-described measuring methods. The evaluation results of each characteristic are shown in Tables 1 to 3.

[0058]

[Table 1] (Note) 0.07, 0.50 or more causes problems when there is no background dirt

[0059]

[Table 2] (Note) 0.07, 1.0 or more causes a problem when there is no toner scattering.

[0060]

[Table 3]

[0061]

As described above, according to the first aspect of the present invention, as a binder resin and a charge controlling agent, 97.0 to 99.5% by weight of the repeating unit represented by the above formula (1) and the above formula (1) It is composed of 3.0 to 0.5% by weight of the repeating unit represented by 2), and has a weight average molecular weight of 5,000 to 25,000.
And the melt viscosity at 100 ° C. is 1.
A positive toner containing a quaternary ammonium salt group-containing copolymer in a range of 0 × 10 ^{4 to} 5.0 × 10 ⁴ ,
According to this, even if copying is repeated many times, background stain and toner scattering are suppressed, and a positive polarity toner having a high image density can be obtained.

According to a second aspect of the present invention, in the constitution of the first aspect, the melt viscosity ηR of the binder resin at 100 ° C. and the melt viscosity ηCCA of the quaternary ammonium base-containing copolymer at 100 ° C.
Where 2 <ηR / ηCCA <10
According to this, the compatibility between the two becomes better, and uniform dispersion can be performed, so that background contamination and toner scattering can be further suppressed.

According to a third aspect of the present invention, in the configuration of the first or second aspect, Tg (shoulder value) of the binder resin is set to Tg.
R, when Tg (peak value) of the quaternary ammonium salt group-containing copolymer is TgCCA, the Tg of both is 0.8 <
TgR / TgCCA <1.0. According to this, the compatibility between the two becomes better,
Since uniform dispersion can be performed, background contamination and toner scattering can be further suppressed.

The invention of claim 4 is the invention of claim 1, 2 or 3
In the configuration of, the binder resin is a polyester resin,
The polyester resin is not only excellent in low-temperature fixability, but also extremely excellent in compatibility with the quaternary ammonium salt group-containing copolymer, and can perform uniform dispersion.

The invention of claim 5 is the invention of claim 1, 2, or 3.
In the above structure, the binder resin is a combination of a polyester resin and a styrene-acrylic copolymer, and the styrene-acrylic copolymer is used in combination to cover the pulverizability of the polyester resin, and the toner Productivity can be increased.

In a sixth aspect of the present invention, in the constitution of the fifth aspect, the melt viscosity ηPE of the polyester resin at 100 ° C. and the melt viscosity ηS of the styrene-acrylic copolymer at 100 ° C.
t, the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer ηCCA is set to satisfy the relationship of ηCCA <ηSt <ηPE, whereby the compatibility of the three is favorably improved. And uniform dispersion can be achieved.

According to a seventh aspect of the present invention, in the constitution of the fifth aspect, the Tg (shoulder value) of the polyester resin is set to TgP.
E, the Tg of the styrene-acrylic copolymer is TgSt,
The Tg of the quaternary ammonium salt group-containing copolymer is defined as Tg
When CCA is used, Tg of the three is expressed as TgPE <TgSt ≦
TgCCA is to be established, and by doing so, the three-part toner keeps good storability against heat and does not hinder the low-temperature fixability of the toner.

The invention of claim 8 is the invention of claim 5, 6, or 7.
In the configuration of the above, a styrene-butyl acrylate copolymer is used as the styrene-acrylic copolymer, and the styrene-butyl acrylate copolymer is the same as the quaternary ammonium base-containing copolymer. Are particularly excellent in compatibility, and uniform dispersion can be performed.

The ninth aspect of the present invention is the first aspect of the present invention.
Or in the constitution of 7, wherein the particle size of the quaternary ammonium salt group-containing copolymer is 2.0 mm or less,
Thereby, even when the kneading time is short, the dispersion of the quaternary ammonium salt group-containing copolymer in the binder resin is not deteriorated.

The tenth aspect of the present invention is the first aspect of the present invention.
In the constitution 6 or 7, not only the particle size of the quaternary ammonium salt group-containing copolymer but also the particle size of the binder resin is set to 2.0 mm or less. The dispersion of the ammonium group-containing copolymer is improved, and uniform dispersion can be achieved for each of the binder resins.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideyuki Ueda 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd. (72) Inventor Akira Oyamaguchi 1-3-6 Nakamagome, Ota-ku, Tokyo Ricoh Co., Ltd. (72) Inventor Kazuto Watanabe 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. (72) Inventor Osamu Uchinokura 1-3-6 Nakamagome, Ota-ku, Tokyo Co., Ltd. Ricoh F term (reference) 2H005 AA01 AA06 CA03 CA04 CA08 CA28 DA03 EA03 EA05 EA06 EA07

Claims (10)

[Claims] 1. As a binder resin and a charge controlling agent, 97.0 to 99.5% by weight of a repeating unit represented by the following general formula (1) and a repeating unit 3.0 represented by the following general formula (2).
0.5% by weight and a weight average molecular weight of 50
A positive electrode comprising a quaternary ammonium salt group-containing copolymer having a melt viscosity at 100 ° C. of 1.0 × 10 ^{4 to} 5.0 × 10 ^4. Toner. Embedded image In the formula, R ₁ represents a hydrogen atom or a methyl group. Embedded image In the formula, R ₂ represents a hydrogen atom or a methyl group, R ₃ represents an alkylene group, and R ₄ , R ₅ and R ₆ represent an alkyl group. 2. The positive polarity toner according to claim 1, wherein
The melt viscosity at 100 ° C. of the binder resin is ηR,
When the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is defined as ηCCA, the relationship between the melt viscosities is represented by the following formula. ## EQU1 ## 2 <ηR / ηCCA <10 3. The positive polarity toner according to claim 1, wherein Tg (shoulder value) of the binder resin is TgR.
And the Tg of the quaternary ammonium salt group-containing copolymer
When the (peak value) is defined as TgCCA, the relationship of the Tg is represented by the following formula. 0.8 <TgR / TgCCA <1.0 4. The positive polarity toner according to claim 1, wherein said binder resin is a polyester resin. 5. The positive polarity toner according to claim 1, wherein the binder resin is a combination of a polyester resin and a styrene-acrylic copolymer. 6. The positive polarity toner according to claim 5, wherein
The melt viscosity of the polyester resin at 100 ° C. is η
PE, the melt viscosity at 100 ° C. of the styrene-acrylic copolymer is ηSt, and the melt viscosity at 100 ° C. of the quaternary ammonium salt group-containing copolymer is ηCCA. A positive polarity toner characterized by the following: ## EQU3 ## ηCCA <ηSt <ηPE 7. The positive polarity toner according to claim 5, wherein
The Tg (shoulder value) of the polyester resin is defined as TgP
E, the Tg of the styrene-acrylic copolymer is TgS
t, wherein Tg of the quaternary ammonium group-containing copolymer is TgCCA, and the relationship of the Tg is represented by the following formula. ## EQU4 ## TgPE <TgSt ≦ TgCCA 8. The positive toner according to claim 5, wherein the styrene-acrylic copolymer is a styrene-butyl acrylate copolymer. 9. The positive polarity toner according to claim 1, wherein the quaternary ammonium group-containing copolymer has a particle size of 2.0 mm or less. toner. 10. The positive polarity toner according to claim 1, wherein the binder resin and the quaternary ammonium salt group-containing copolymer each have a particle size of 2.0 mm or less. A positive polarity toner characterized by the following.