JPH07104518A - Toner for electrostatic charge image developer and dry developer - Google Patents

Abstract

PURPOSE:To obtain a toner excellent in aging stability by using a specified metallic complex salt compd. having satisfactory compatibility with a resin and to provide a dry developer. CONSTITUTION:A nickel dithiolato complex represented by the general formula is incorporated into a toner for an electrostatic charge image developer based on a resin and a colorant to obtain the objective toner. In the formula, each of R1 and R2 is H, 1-20C alkyl, optionally substd. phenyl, an optionally substd. aliphatic group, nitro, nitrile, ester, alkoxy, amino, chalcogenide or a halogen atom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for an electrostatic charge developer and a dry developer useful for developing an electrostatic charge image formed in an electrophotographic method.

[0002]

2. Description of the Related Art In electrophotography, after a photoconductor is uniformly charged, a photoimage based on the original image is exposed on the photoconductor to eliminate or reduce the electric charge in the light-irradiated portion to form the original image on the photoconductor. It is well known in the art to form an electrostatic latent image corresponding to No. 1 and then visualize it with a so-called two-component dry developer composed of carrier particles and toner particles to obtain a copy. In this two-component dry developer, minute toner particles are held on the surface of a relatively large carrier particle by the electric force generated by the friction of both particles, and when the electrostatic latent image is approached, the electrostatic latent image is formed. The attraction force in the latent image direction on the toner particles due to the electric field formed overcomes the binding force between the toner particles and the carrier particles, and the toner particles are attracted and attached onto the electrostatic latent image to visualize the electrostatic latent image. It is what is done.
The characteristics required for this toner are chargeability,
Hygroscopicity, stability over time, fluidity, and the like are mentioned, and among these characteristics, chargeability, hygroscopicity, and stability over time are greatly affected by the charge control agent contained in the toner. As a conventional charge control agent for toner, as a negative charge control agent, a Cr-containing Co complex (JP-A-61-217061, JP-A-63-216061), nitrohumic acids (JP-A-50-133838) is used. ), A phthalocyanine pigment (JP-A-60-258560), and the like,
As a positive charge control agent, a nigrosine-based dye salt (JP-A-56)
No. 22441), various quaternary ammonium salts (JP-A-59-136747), and imidazole derivatives (JP-A-3-72373) are known, but toners using these control agents have chargeability. However, the hygroscopicity and the temporal stability are not sufficient, and it is difficult to say that the compatibility of the control agent itself with the binder is also sufficient. For example, a toner using a nigrosine dye, which is publicly known as a positive charge control agent, has relatively high electric power in itself, but has poor adhesion to a substrate, and since it is black in itself, it has a limited application range. There is a drawback that it can only be used for the toner. Further, the toner using the quaternary ammonium salt has a very high hygroscopic property,
As a result, there is a drawback in that it lacks temporal stability and is inferior in repetitive image forming ability.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is a toner for an electrostatic image developer, which exhibits negative charge controllability and has good compatibility with a resin. By using a metal complex salt compound, a toner for an electrostatic image developer and a dry developer for solving the above problems are provided.

[0004]

SUMMARY OF THE INVENTION The present invention comprises a toner for electrostatic charge development, which comprises a nickel dithiolate complex represented by the following general formula (I) in a toner for electrostatic charge development, and a toner using the same. It relates to a charge image developer.

[0005]

[Chemical 1] (In the formula, R ₁ and R ₂ may be the same or different from each other, and are a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted aliphatic group,
It represents a nitro group, a nitrile group, an ester group, an alkoxy group, an amino group, chalcogenite or a halogen atom. )

The nickel dithiolate complex used in the toner of the present invention is a column chromatograph or recrystallized crystal obtained by heating dithiolate sodium salt represented by the following general formula (II) and nickel nitrate under reflux in an organic solvent. It can be obtained by crystals.

[0007]

[Chemical 2] (In the formula, R ₁ and R ₂ are the same as in the general formula (I).)

Substituents R ₁ and R ₂ in the general formula (I)
Examples of are methyl group, ethyl group, hexyl group, n
-Alkyl group such as propyl group, i-propyl group, n-butyl group, t-butyl group, n-hexyl group, cyclohexyl group, n-octyl group, n-dodecyl group, substituted or unsubstituted phenyl group, benzyl Examples thereof include a group, an alkoxy group and a nitro group, a nitrile group, an ester group, a methylthio group, a phenylthio group, a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. In addition, as a substituent substituting a phenyl group and a benzyl group, a methyl group, an ethyl group, n-
Alkyl group such as propyl group, n-butyl group, t-butyl group, methoxy group, ethoxy group, n-propoxy group, t
Examples thereof include an alkoxy group such as butoxy group, a nitro group, a cyano group, a halogen atom, and an alkyl group, an alkoxy group, a nitro group, a cyano group, and a mono-substituted, di-substituted or tri-substituted product of a halogen atom. Specific examples of the nickel dithiolate complex as the negative charge control agent of the present invention are shown below, but the invention is not limited thereto. Less than
margin

[0009]

[Table 1-1]

[0010]

[Table 1-2]

Examples of resins that can be used in the present invention include polystyrene resins, acrylic resins, styrene-methacrylic copolymers, and epoxy resins. As the colorant, for example, Kayset Yellow E
-2 R (CI Pigment Y manufactured by Nippon Kayaku Co., Ltd.
Ellow 142), KayaseRed AG
(C.I. Solvent Red 179), K
Ayaset Blue FR (CI Solven
t Blue 105), carbon black, and the like, but are not limited thereto. The content of the general formula (I) of the present invention is 05. -30 parts, preferably 1-10 parts. If it is 0.5 parts or less, problems tend to occur in terms of sufficient offset prevention effect, and if it is 30 parts or more, gelation may occur, which is not preferable. Also, polypropylene, polyethylene,
Add various additives such as fixability improver such as carnauba wax, fluidity improver such as hydrophobic silica, alumina, molybdenum sulfide and titanium oxide, cleaning improver such as zinc stearate, magnesium stearate and zinc laurate. You can As the carrier, magnetic materials such as iron, nickel, cobalt and ferrite are preferably used.

The toner of the present invention is obtained by melting and kneading the above-mentioned resin, colorant, charge control agent and the like by a device capable of heating and mixing such as a heating kneader and two rolls, and then cooling and solidifying the jet mill, ball mill and the like. 1 to 50 depending on the crusher
It can be obtained by pulverizing to a particle size of μm. As another method, a resin is dissolved in a solvent, a charge control agent is added thereto, and the mixture is stirred, poured into water for reprecipitation, filtered, dried, and then pulverized with a crusher such as a ball mill.
It can also be obtained by pulverizing to a particle size of ˜50 μm.

The present invention will be specifically described below based on examples, but the invention is not limited thereto. In addition,
Parts in the examples indicate parts by weight.

Example 1 Toner Production Styrene-methyl methacrylate copolymer 100 parts Exemplified Compound No. 4 5 parts Carbon black 10 parts [Example 2] Production of toner Polyester resin 100 parts Exemplified Compound No. 6 5 parts Carbon black 10 parts [Example 3] Production of toner Epoxy resin 100 parts Exemplified Compound No. 1 10 parts Carbon black 10 parts [Comparative Example 1] Production of toner Styrene-methyl methacrylate copolymer 100 parts Metal-containing monoazo dye 5 parts (Hodogaya Chemical Co., Ltd. Spyron Black TOH) Carbon black 10 parts Toner components were blended, kneaded with a hot roll, pulverized and classified to prepare toners of the present invention and comparative particles having an average particle diameter of 8.0 μm. These toners are EFV20
A dry developer having a toner concentration of 7% was prepared by mixing with 0 to 300 mesh iron powder (manufactured by Nippon Iron Powder Co., Ltd.) and stirring, and the following evaluations were performed.

1. Durability As for durability, electrophotographic copying machine (FT4 manufactured by Ricoh Co., Ltd.
No. 060), continuous copying of 20,000 sheets is performed, and the toner charge amount (μC / gr) of the developer at the initial stage and after the copying is measured,
Image evaluation was performed. 2. Environmental test Regarding the environmental test, the toner and carrier should be treated under high humidity conditions (3
After adjusting the humidity in an atmosphere of 0 ° C. and a humidity of 90% for 2 hours) and low humidity conditions (10 ° C., a humidity of 30%), the toner and the carrier are mixed and stirred in the same manner as above to prepare a developer for each. The toner charge amount (μC / gr) of the developer was measured and evaluated by the variation rate at high humidity and low humidity. The evaluation results are shown in Table 2.

[0016]

[Table 2] * At the time of copying 10000 sheets * * Significant soiling occurs.

[0017]

[Effect] The toner for an electrostatic image developer containing the nickel dithiolate complex of the present invention has little change in the charging characteristics due to the environment, and the image quality does not deteriorate even after repeated continuous copying.

Claims (3)

[Claims] 1. A toner for an electrostatic charge developer, which comprises a resin and a colorant as main components, and contains a nickel dithiolate complex represented by the following general formula (I). [Chemical 1] (In the formula, R ₁ and R ₂ may be the same or different from each other, and are a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted phenyl group, a substituted or unsubstituted aliphatic group,
It represents a nitro group, a nitrile group, an ester group, an alkoxy group, an amino group, chalcogenite or a halogen atom. ) 2. A resin 10 containing the nickel dithiolate complex.
The toner for an electrostatic charge developer according to claim 1, wherein the toner is contained in an amount of 1 to 10 parts with respect to 0 parts. 3. A dry developer containing the toner according to claim 1 and a carrier.