JPH0248677A - Toner for electrophotography - Google Patents

Abstract

PURPOSE:To obtain the toner which has excellent mechanical friction and impact stability, temp. and temp. stability, etc., forms colorless and sharp images and is continuously usable by incorporating the compd. expressed by the general formula I as the charge control agent of the toner for electrophotography into the toner. CONSTITUTION:The toner for electrophotography contains compd. expressed by the general formula I as the charge control agent of the toner. In the formula I, R denotes a hydrogen atom, alkyl group, alkoxy group, halogen atom; k, l, m, and n denote 1-4. Further, X denotes O=C-O, O=C-NR', SO3SO2NR', O, S, and NR'; Y denotes O, S or NR' (R' denotes a hydrogen atom or alkyl group); Z<+2> denotes cation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a toner for developing electrostatic latent images in electrophotography.

(Prior art) In electrophotography, a latent image is formed on a photoconductor made of a photoconductive substance, and this is developed with a powder developer to make it visible. A common method is to fix it on paper using a method. Developers for such electrophotography include natural resins or synthetic resins, colorants,
A two-component developer consisting of a mixture of a toner in which a charge control agent, a fluidizing agent, etc. are dispersed and a carrier of iron powder or ferrite powder, and a natural resin or synthetic resin, a coloring agent, a charge controlling agent, a fluidizing agent, It can be roughly divided into one-component developers made of magnetic materials.

A two-component developer achieves development by attaching charged toner to an electrostatic latent image through friction with a carrier. Conventionally, a one-component developer uses this instead of a carrier. It is known that toner is charged by friction with a brush-like or plate-like friction member that has a similar function to that of a toner. Toners that are charged by mutual friction have become known. The photoconductor layer can be positively or negatively charged so that exposure under the original produces a positive or negative electrostatic latent image. Depending on the polarity of this electrostatic latent image, the developing toner remains positive or negative.

In order to keep the toner charged, it has been proposed to utilize the triboelectricity of the resin, which is the main component of the toner, but this method has a small charge t on the toner and a large solid surface resistance value. , the resulting image is likely to be foggy and unclear. Therefore, in order to impart desired triboelectric charging properties to the toner, it has been attempted to add charge-imparting dyes, pigments, and even charge control agents, and these techniques are now in practical use in this technical field.

(Problems to be Solved by the Invention) However, these dyes and pigments used as charge control agents have complex structures and lack stability, such as mechanical friction and impact, changes in temperature and humidity conditions, and electrical resistance. It is easily decomposed or altered by impact, light irradiation, etc., and the charge adjustment ability is easily lost. One essential flaw is that, being a colored material, it violates the requirement that toners with a specific hue require a charge control agent that can be considered colorless or substantially colorless. .

(Means for Solving the Problems) The present inventors have discovered a colorless substance that has good dispersibility with the resin component, is thermally stable up to a temperature that allows sufficient melting, and is colorless. They discovered a compound capable of imparting a negative charge to toner and invented an excellent toner.

That is, the present invention is a general formula) (In the formula, R5 atom, A7゜ki7゜ group, A2゜yoxy group, halogen atom, k1ρ, and Vn are 1.2
．． 3 or 4, and X is the anion number.

The structural formula, NR', and Y represent OSS or NR'(R' represents a water atom or an alkyl group), and Z(f) represents a cation. ) is a toner for electrophotography characterized by containing a compound represented by the following as a charge control agent.

Specific examples of the 7-ion of the compound represented by general formula (I) are shown below.

Aion No., Structural Anion No.

Anion No.

7ion no.

Further, examples of the cation of the compound represented by the general formula (I) include hydrogen ions and alkali metal ions. Examples of alkali metal ions include Li+, Na'', K+, etc. Examples of organic cations include ammonium ions, iminium ions, and phosphonium ions.

Among the above cations, preferred ones are represented by the following general formula (n)
, (I[I), (IV) or (V).

In the formula, R2, R3, R1, R5, R7, R8, R4, R8° and Rl+ each represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted 7-aryl group. , Zl and Z2 represent a group of nonmetallic atoms that combine with the nitrogen atom in each formula to form a five-shell or six-shell ring. Examples of the alkyl group include methyl group, ethyl group, n-butyl group, 1so-amyl group, n-dodecyl group, n-octadecyl group, and cyclohexyl group. Examples of the aryl group include a phenyl group and an a-7tyl group. These alkyl groups may be substituted with various substituents such as an alkyl group, an aralkyl group, an alkoxy group, a hydroxyl group, a cyano group, an aryl group, etc.). Further, Z and Z2 can include, for example, nonmetallic atomic groups necessary to form various heterocycles such as a pyridine ring, an isoquiline ring, a pyrrole ring, an imidazole ring, a piperidine ring, and a pyrrolidine ring.

Compound (I) used as a charge control agent of the present invention can be prepared, for example, by adding the following general formula (It) to an aqueous solution of boric acid and an amine (where R, to, n, X, and Y are the same as the compound date). It can be easily obtained by adding and reacting the compound.

Incidentally, the amount of the compound represented by general formula (I) added to the toner component is generally 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight, based on 100 parts by weight of the resin. Make it contain.

The toner of the present invention comprises a compound of the above general formula (I) containing:
Styrene resin, styrene-acrylic resin, styrene. One type or a mixture of several types of known toner resins such as butadiene resin, epoxy resin, polyester resin, and paraffin wax are used. As the coloring agent, many known dyes and pigments can be used, but those that are particularly excellent as toners for color toners include benzidine yellow, quinacridin, copper 7 talocyanin blue, copper 7
Examples include talocyanine green.

The toner of the present invention is usually mixed with a carrier to provide a two-component developer, but can of course also be used as a one-component developer.

(Example) Hereinafter, the present invention will be explained in detail with reference to Examples.

Note that parts in the examples represent parts by weight.

Example 1 A mixture of 100 parts of styrene resin, 6 parts of carbon black, and 2 parts of Bologie 2.2'-Bi7/-dimethylammonium is uniformly premixed in a ball mill to prepare a premix. Next, the mixture was heated and melted and kneaded, cooled, and then coarsely pulverized using a vibration mill and further finely pulverized using a jet mill to obtain a black toner.

The particle size of this black toner was 8 to 15 μI.

A developer was prepared by mixing 95 parts of iron powder carrier with 5 parts of the obtained toner. The initial blow-off charge amount of this developer was -27.1 μC/g.

When a toner image was formed using this developer on a commercially available selenium drum using a magnetic brush development method, a clear image without fogging was obtained. With this toner, no deterioration in copy quality was observed after 10,000 continuous copies were made.

Example 2 100 parts of styrene-acrylic copolymer 81 fat, yellow dye (
C. 1. Disbirds Yellow 33) 6 parts, Borobis (
5,5'-terL-butyl-2-hydroxy-
A formulation of 2 parts of dimethylammonium (2-biphenylcarboxylate) was treated in the same manner as in Example 1 to obtain a yellow toner. The initial blow-off charge amount of the developer prepared from the obtained yellow toner in the same manner as in Example 1 was -26.8 μC/g.
Met.

When copies were made using this developer in the same manner as in Example 1, clear yellow images without fog were obtained. With this toner, no deterioration in copy quality was observed even after 10,000 continuous copies were made.

Example 3 Styrene-lobyl methacrylate copolymer resin 10
0 parts, red dye (C, I, Pigment Red 12) 8
1 part, 2 parts of borobis(2-amino-2'-hydroxybiphenyl)tri(n-butyl)ammonium was treated in the same manner as in Example 1 to obtain a red toner. The developer prepared from the obtained red toner in the same manner as in Example 1 had an initial blow-off charge amount of -29.4 μC/g.

When copies were made using this developer in the same manner as in Example 1, clear red images without fog were obtained. With this toner, no decrease in the quality of copies was observed even after continuous copying of 1001) sheets.

Example 4 100 parts of polyester resin, blue dye (C, I.

Pigment Blue 15) and 2 parts of diethylammonium borobis(2'-amino-5'-methyl-2-biphenylcarboxylic acid) were treated in the same manner as in Example 1 to obtain a blue toner. The initial blow-off charge amount of the developer prepared from the obtained blue toner in the same manner as in Example 1 was -
It was 26.3 μC/g.

When copies were made using this developer in the same manner as in Example 1, clear blue images without fog were obtained. With this toner, no deterioration in copy quality was observed even after 10,000 continuous copies were made.

Example 5 Borobis(5′-chloro-2′-hydroxy-2- and 722lsulfonic acid)benzyltrimethylammonium was used instead of HO:/-2,2″-bi72/-lunomethylammonium. A black toner was obtained in the same manner as in Example 1 except that the developer was prepared in the same manner as in Example 1.The initial blow-off charge amount of the developer prepared from the obtained black toner was -2.
It was 3.4 μC/g.

Example 6 Borobis(5,5'-di-tert-butyl-2'-human axy-2-biphenylcarboxylic acid) dimethylammonium was replaced by
A yellow toner was obtained in the same manner as #N2, except that -butyl-2,2'-dithiobi7/-l)phenyltrimethylammonium was used. The developer prepared from the obtained yellow toner in the same manner as in Example 1 had an initial blow-off charge amount of -25.2 μC/g.

Example 7 Borobis(2-7mi/-2′-hydroxybiphenyl)
A red toner was obtained in the same manner as in Example 3, except that borobis(2'-hydroxy-4'-methoxy-2-biphenylcarboxamide) N-butylpyridinium was used instead of tri(n-butyl)ammonium. The developer prepared from the obtained red toner in the same manner as in Example 1 had an initial blow-off charge amount of -27.8 μC/g.

Example 8 The same procedure was carried out except that borobis(2′-hydroxy-2-biphenylsulfonamido)benzyltriphenylphosphonium was used instead of borobis(2′-7minor-5′-methyl-2-biphenylcarboxylic acid)diethylammonium. A blue toner was obtained in the same manner as in Example 4. Initial blow-off of the developer prepared from the obtained blue toner in the same manner as in Example 1? #The amount of electricity was -20.3 μC/g.

(Effects of the Invention) The charge control agent used in the present invention has excellent mechanical friction and impact stability, temperature and humidity stability, and is colorless, so it is an electrophotographic toner that provides clear images and can be used continuously. was gotten.

Patent applicant Nippon Carlit Co., Ltd.

Claims (1)

[Claims] The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (In the formula, R represents a hydrogen atom, an alkyl group, an alkoxy group, or a halogen atom, and k, l, m and n is 1, 2, 3 or 4, and X is ▲a mathematical formula, a chemical formula, a table, etc.▼, ▲a mathematical formula, a chemical formula,
There are tables, etc. ▼, SO_3, SO_2NR', O, S
and NR', Y represents O, S or NR'(R' represents a hydrogen atom or an alkyl group), and Z^■ represents a cation. ) A toner for electrophotography, characterized in that it contains a compound represented by the following as a charge control agent.