JPS62966A - Toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To enable high-speed continuous copying and to obtain a clear image without causing defective electrostatic charging even in an atmosphere at high humidity by using a toner contg. oleic acid or resin acid together with a quat. ammonium salt as a color toner. CONSTITUTION:The quat. ammonium salt is added to a resin binder by 1-5pts. wt. per 100pts.wt. resin binder, and oleic acid or resin acid is further added by 25-150pts.wt. per 100pts.wt. quat. ammonium salt. In case of <1pts.wt. quat. ammonium salt per 100pts.wt. resin binder, prescribed charges are not obtd., and in case of >5pts.wt. effect is not further enhanced and the cost is increased. In case of <25pts.wt. stearic acid per 100pts.wt. quat. ammonium salt, satisfactory stability and moisture resistance are not maintained during long-run copying, and in case of >150pts.wt., coloring with a dye or pigment is made unclear.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a toner for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, and the like.

<Prior art> Conventionally, as an electrophotographic method, U.S. Patent No. 2,297.69
Many methods are known, including the one described in Specification No. 1, but the toner used for the development is, for example, a positive polarity toner to develop a negative electrostatic latent image formed on a zinc oxide photoreceptor, etc. is used.

This toner is generally made by melt-kneading a thermoplastic resin, a charge control agent, and a coloring agent and then finely pulverizing the mixture, and the charge control agent used here is usually a basic nigrosine dye.

<Problems to be Solved by the Invention> Incidentally, when producing a positive polarity color electrophotographic toner, the selection of a charge control agent is a major issue, and the conventionally used basic nigrosine dye itself is black. Therefore, it is not applicable to color toners that require clear color tones such as cyan, magenta, and yellow, and other conventionally known coloring materials such as asphalt materials are also not applicable. .

Therefore, there is a need for a light-colored home appliance control agent that can be considered colorless or substantially colorless.

By the way, quaternary ammonium salts have long been known as positive charge control agents, and although they are virtually colorless, they are not put to practical use because they cause charging failures not only in high-speed continuous copying but also in high-humidity environments. The current situation is that this is not the case.

Means for Solving the Problems> In view of the above-mentioned circumstances, the present invention has made extensive research into a toner that can solve the above-mentioned technical problems while using a quaternary ammonium salt, which has not been considered in the past. As a result, it was discovered that a toner containing oleic acid or resin acid together with a quaternary ammonium salt can be used as a color toner, and the present invention was achieved.

<Example> The preferred optimal composition for carrying out the present invention is binder resin 1.
00 parts by weight of a quaternary ammonium salt and 100 parts by weight of a quaternary ammonium salt containing 25 to 150 parts by weight of oleic acid or resin acid. It's toner.

Examples of the binder resin include polystyrene, poly p-chlorostyrene, polyvinyl ketone, styrene-p-chlorostyrene copolymer, styrene-propylene copolymer,
Styrene vinyl ketone copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene, ethyl acrylate copolymer, styrene-
Methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-alpha chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ketone copolymer, styrene-vinyl methyl Styrenic copolymers such as ether copolymers, styrene-isoprene copolymers, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, silicone resins, polyurethane, polyamides, epoxy resins, polyvinyl butyral resins, phenolic resins, xylene Examples include resins, aliphatic or alicyclic hydrocarbon resins, chlorinated paraffins, and these can be used alone or in combination.

Examples of the quaternary ammonium salt include (3-laurylamide propyl)-trimethylammonium methyl sulfate, tetrapentylammonium, myristyldimethylammonium ethyl sulfate, cetyldimethylethylammonium ethyl sulfate, and the like.

Coloring agents that can be used in color electrophotographic toners include benzine yellow, monoazo dyes, and nitrophenylamine sulfonamide, and magenta includes quinacridone, anthraquinone dyes, and diazo dyes. For cyanide, steel phthalocyanine, indanthremble, etc. can be used. Note that other known dyes and pigments can be used in the case of black and white images (not in color).

In addition, in the present invention, deviating from the preferred composition range, 1 quaternary ammonium salt is added to 100 parts by weight of the binder resin.
If the amount is less than 5 parts by weight, the specified charge cannot be obtained;
If the amount exceeds parts by weight, the effect will be saturated and the cost will increase. Furthermore, if the amount of stearic acid is less than 25 parts by weight per 100 parts by weight of the quaternary ammonium salt, the stability in long-run copying and high-humidity properties will be insufficient, and if it exceeds 150 parts by weight, the desired effect will not be obtained. This is not preferable because it becomes excessive and makes the coloring of the dye and pigment unclear.

Examples of the present invention will be shown below.

Example 1 Styrene-acrylic copolymer resin (
Briolide AC, manufactured by Gutdeyer) 100 parts by weight, quaternary ammonium salt (Bontron P-51, manufactured by Orient Chemical Co., Ltd.) 3 parts by weight, oleic acid 3 parts by weight, colorant red organic pigment (Seiryoku Fast Red LR-1215)
, manufactured by Dainichiseika Chemical Co., Ltd.) were heat-kneaded, cooled, and then used in a jet pulverizer to obtain a red toner having a particle size of 10 to 15 μm.

Example 2 Styrene-acrylic copolymer resin (
Briolide AC, Gutdeyer Co., Ltd.) 100 parts by weight, quaternary ammonium salt (Bontron P-51, Orient Chemical Co., Ltd.) 4 parts by weight, oleic acid 4 parts by weight, blue phthalocyanine pigment (Linol Blue SM, Toyo Ink Co., Ltd.) ) were heat-kneaded, cooled, and then milled using a jet pulverizer to obtain a blue toner having a particle size of 10 to 15 μI.

Example 3 Ebokire resin (Ebototo YDO14) was used as a binder resin.
, manufactured by Toto Kasei Co., Ltd.) 100 parts by weight, quaternary ammonium salt (Bontron?-5L manufactured by Orient Chemical Co., Ltd.) 3 parts by weight,
3 parts by weight of oleic acid and 5 parts by weight of carbon black (Mitsubishi Carbon #401 manufactured by Mitsubishi Kasei Corporation) were hot kneaded, cooled, and then used in a jet pulverizer to obtain a black toner having a particle size of 10 to 15 μm.

Comparative Example 1 A red toner was obtained using the same formulation and treatment as in Example 1 except that oleic acid was not added.

Comparative Example 2 Polyamine shown in Japanese Patent Publication No. 59-41184 (Bontron AFP-B, manufactured by Orient Chemical Co., Ltd.) as a charge control agent
A red toner was obtained in the same manner as in Comparative Example 1 except that .

For each of the above toners, 5 parts by weight were mixed and stirred with 100 parts by weight of fluororesin-coated iron powder carrier (TSV-C52, manufactured by Nippon Tetsuko Co., Ltd.) to prepare a developer. The stability and charge stability in a high humidity atmosphere were investigated. The charge was measured using a blow-off powder charge measuring device (manufactured by Toshiba Chemical Corporation). The data are shown in the following table, and it can be seen that the toners of Examples are excellent. Note that although a PPC copying machine having a zinc oxide photoreceptor was used, there is no significant difference in the results even if one having an OPC photoreceptor is used.

2) High humidity characteristics <Effects of the invention> As is clear from the above comparative tests, the present invention has stable image characteristics not only for normal black toner but also for all color toners including red and blue. It has the ability to obtain particularly clear images, and even continuous copying can be performed at 5.
Even after copying 1,000 copies, the image is almost clear, and it is also possible to obtain clear images even when placed in extremely high temperature environments such as during the rainy season. It is possible to provide an effective toner.

Claims (2)

[Claims] (1) A toner for developing electrostatic images containing a quaternary ammonium salt and oleic acid or resin acid. (2) A patent claim containing 1 to 5 parts by weight of a quaternary ammonium salt to 100 parts by weight of the binder resin, and 25 to 150 parts by weight of oleic acid or resin acid to 100 parts by weight of the quaternary ammonium salt. The toner for developing an electrostatic image according to item 1.