JPS59172655A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To obtain a positive toner good in developability characteristics and long in life by mixing a specified substance with a toner. CONSTITUTION:An intended positively chargeable toner can be obtained by mixing with an electrostatic charge image developing toner a benzotriazole compd. represented by formula I in which R1, R2, R3 are each H, alkyl, aryl, aralkyl, alkoxy, aryloxy, aralkyloxy, cyclohexyl or halogen, and said alkyl group and aryl ring may be substd. Said compd. of formula I can be obtained, e.g., by diazotizing one of o-nitroanilines, coupling it with one of phenols, and reducing the obtained monoazocompd. of formula II and cyclizing it with zinc in the presence of caustic alkali.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for converting electrostatic latent images such as electrophotography or electrostatic recording into
jlRegarding toner used during development.

Methods for developing electrostatic latent images using toner include the magnetic brush method, which uses developer powder containing carrier particles, mainly iron powder, and the cascade method, which uses developer powder containing glass particles as carrier particles. It has been known.

The developing powders used in these developing methods include fine powders in which dyes or pigments are dispersed in thermoplastic resins, as well as powders such as those described in Japanese Patent Publication No. 44-68'98, etc.
Developing powders with added substances are also known. However, since the above developer powder alone does not have desirable charging properties, dyes or pigments that impart charging properties are added, and currently in practical use, when imparting a negative charge to toner, When a metal-containing dye imparts a positive charge, there is a nigrosine dye. These dyes are charge control agents with excellent properties, but because they are colored substances, they cannot be used in color electrophotography in which Ml is particularly strong in recent years. In addition, toners containing nigrone dyes used for positive donors exhibit good development characteristics initially, but have the disadvantage of short lifespans. There is a strong demand for colorless or light-colored charge control agents. However, no charge control agent satisfying the above characteristics has yet been found.

An object of the present invention is to provide a long-life positive donor with good development properties.

In other words, the present invention provides a toner for use in developing electrostatically charged images having the general formula (I) [wherein R1, R2, and R9 are hydrogen atoms, alkyl groups, aryl groups, aralkyl groups, alkoxy groups, and aryl groups] Represents an oxy group, an aralkyloxy group, a cyclohexyl group, or a haloken atom.

In the substituents R4, R2, and Ra, the alkyl chain and aryl ring may be substituted. This is a toner for developing electrostatic images characterized by containing a benzotriazole represented by the following.

In the general formula (I'), the substituents Rt, R2, R8 include a hydrogen atom, a methyl group, an ethyl group, a propyl group,
Alkyl groups which may be branched such as butyl group, hexyl group, dodecyl group, substituted alkyl groups such as methoxyethyl group, ethoxyethyl group, butoxyethyl group, chloroethyl group, dimethylaminoethyl group, phenyl group, tolyl group, Aryl groups such as butylphenyl, butoxyphenyl, and chlorphenyl groups; aralkyl groups such as benzyl, phenethyl, and methylbenzyl; alkoxy groups such as methoxy, ethoxy, propoxy, butoxy, and octoxy groups; , phenoxy group, methylphenoxy group, quinphenoxy group, aryloxy group such as chlorophenoxy group, aralkyloxy group such as penciloxy group, methylbenzyloxy group, chlorobenzyloxy group, cyclohexyl group, fluorine atom, Typical substituents include halogen atoms such as chlorine atom, bromine atom, and iodine atom at 1°.

The compound represented by the general formula (I) can be obtained by a known method, for example, by diazotizing 0-nitroaniline and then coupling it to a phenol to obtain a monoazo compound of the following general formula (It).

This monoazo compound is subjected to ring formation and cyclization with zinc under caustic alkaline conditions to obtain pendotriazoles represented by general formula (I).

The toner contains a thermoplastic resin and a coloring substance in addition to the charge control agent. Examples of thermoplastic resins include monopolymers or copolymers such as styrene, +p-chlorostyrene, and vinyltoluene, styrene-propylene copolymers, and styrene-vinylnaphthalene. copolymer, styrene-methyl acrylate, ethyl, butyl or octyl copolymer,
Styrene-methyl methacrylate, ethyl or butyl copolymer, styrene-acrylonitrile copolymer, styrene-isobutylene copolymer, styrene-butadiene copolymer, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, Used alone or in combination with polyester, etc.

In addition, colorants include azo dyes, anthraquinone dyes,
Dyes that do not have water-soluble groups such as sulfone groups, such as nitro dyes and quinophthalone dyes, and pigments such as quinacridone and phthalocyanine are used.

By mixing the benzotriazole represented by the general formula (1) of the present invention into a toner, the toner can be positively charged and a long-life toner with good development characteristics can be produced.

The amount of the charge control agent of the present invention mixed in the toner is usually 10% by weight or less, preferably 0.5 to 5% by weight.

The toner of the present invention is mixed with a carrier to form a developer, and is used after being positively charged.

As the carrier, for example, iron powder, glass beads, and those whose surfaces are treated with resin are used.

The present invention will be explained in detail below with reference to Examples.

In the text, parts represent parts by weight.

Example 1 100 parts of styrene-methyl acrylate copolymer, 8 parts of copper phthalocyanine and 2-(2H-benzotriazole-
One part of 2-yl)-4,6-di(-butylphenol) was uniformly premixed in a ball mill for 20 hours, then kneaded in a heated roll mill for 7 minutes, and pulverized to 1 to 40 μm to obtain a powder toner. A developer was prepared by mixing 5 parts of the obtained toner and 95 parts of iron powder, and copying was performed using a dry type electronic copying machine. As a result, good images were obtained and the lifespan was also good.

Example 2 In Example 1, a styrene-butadiene copolymer, an epoxy resin, a polyester resin, a styrene oligomer, or a styrene-acrylic acid resin was used instead of the styrene-methyl acrylate copolymer, and the other conditions were as in Example 1. A good image was obtained by copying in the same manner.

Examples 3 to 14 In Example 1, 27(2H-benzotriazole-
Copying was carried out in the same manner as in Example 1 except that a compound having the following structural formula was used in place of 2-yl)-4,6-di[-butylphenol. As a result, a good image was obtained.

Claims (1)

[Claims] In a toner used for developing an electrostatic charge image, the general formula (
A toner for developing electrostatic images characterized by containing a benzotriazole represented by I) [wherein R1, R2, and R3 are hydrogen atoms, alkyl groups, aryl groups, aralkyl groups, alkoxy groups, and aryloxy] group, aralkyloxy group, cyclohexyl group or halogen atom. In the substituents R+, R2, and Ra, the alkyl chain and aryl ring may be substituted.]