JPS61282850A - Toner for developing electrostatic charge image - Google Patents

Abstract

PURPOSE:To make an image clear and to prevent ground stain by blending a resin binder with a specified amount each of a quat. ammonium salt and stearic acid to produce a toner for developing an electrostatic charge image. CONSTITUTION:A quat. ammonium salt is added to a resin binder by 1-5pts.wt. per 100pts.wt. binder, stearic acid is further added by 25-150pts.wt. per 100pts. wt. quat. ammonium salt, and they are kneaded to obtain a toner for developing an electrostatic charge image. Polystyrene, poly-p-chlorostyrene, polyvinyltoluene or a styrene-propylene copolymer may be used as the resin binder. The quat. ammonium salt may be (3-laurylamidopropyl)-trimethylammonium methylsulfate, tetrapentylammonium or myristyldimethylammonium ethylsulfate.

Description

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

(Prior art) As a conventional electrophotographic method, U.S. Patent No. 2,297,591
A number of methods are known, including those described in the above specification, but the toner used for the development is, for example, for developing a negative electrostatic latent image formed on a zinc oxide photoreceptor, etc.
Positive polarity toner is used.

This toner is generally made by melt-kneading a thermosetting 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.

(Problem that the invention seeks to solve).

By the way, when producing a positive polarity color electrophotographic toner, the selection of a charge control agent is a major issue.A) Since the conventionally used basic Nigezonoshin dye itself is black in color, cyan, Needless to say, it is not applicable to color toners that require clear color tones such as magenta and yellow, and other conventionally known coloring materials such as asphalt materials are also not applicable.

Therefore, there is a need for a charge control material that is colorless or has a light color that can be considered colorless.

By the way, quaternary ammonium salts have long been known as positively charged electric field control agents, and although they are virtually colorless, they are not put into 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 there is no such thing.

(Means for Solving the Problems) In view of the above-mentioned circumstances, the present invention has carried out intensive 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, toner containing stearic acid along with quaternary ammonium salt has a power of 2.
The inventors have discovered that it can be used as a toner for - and have arrived at the present invention.

(Example) The preferred optimum composition for carrying out the present invention is binder resin 10
0 parts by weight, 1 to 5 parts by weight of quaternary ammonium salt, 100 parts by weight of quaternary ammonium salt, and the binder resin is polystyrene, poly p-chlorostyrene, polyvinyltoluene, styrene-p-chloro. Styrene copolymer, styrene copolymer, styrene vinyl toluene 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 Styrenic copolymers such as methyl ether copolymer and styrene-isoprene copolymer, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, silicone resin, polyester resin, polyurethane, polyamide, epoxy resin, polyvinyl butyral resin, Examples of quaternary ammonium salts include phenol resins, xylene resins, aliphatic or alicyclic hydrocarbon resins, and chlorinated paraffins, which can be used alone or in combination. Examples include globil)-trimethylammonium methyl sulfate, tetrapentylammonium, myristyldimethylammonium ethyl sulfate, cetyldimethylethylammonium ethyl sulfate, and the like.

Coloring agents that can be used in Galar electrophotographic toners include benzidine yellow, monoazo dyes, nitrophenylamine sulfonamide, and magenta, such as quinacridone, anthraquinone dyes, and diazo dyes. Also, for cyanide, copper phthalocyanine, indanthremble, etc. can be used. Note that in the case of a black and white image instead of a color image, other known dyes and pigments may be used. □ Note that in the present invention, if the quaternary ammonium salt is less than 1 part by weight for 100 parts by weight of the binder resin outside of the preferred composition range, the desired charge cannot be obtained; If the amount is exceeded, the effect will be saturated and the cost will increase.

Also, 4th. If the stearic acid content is less than 25 parts by weight per 100 parts by weight of the grade ammonium salt, the stability in long-run copying and high humidity properties will be insufficient, and if it exceeds 150 parts by weight, it will be too much to obtain the desired effect. This is not preferable because it makes the coloring of the pigments, dyes, and pigments unclear.

Examples of the present invention will be shown below.

Example 1 Styrene-acrylic copolymer resin (P2Iolai) was used as a binder resin.10. (manufactured by Gutdeyer) 100 parts by weight,
Quaternary ammonium salt (Bontron P-51, manufactured by Orient Chemical Co., Ltd.) 3 parts by weight, stearic acid 5 parts by weight, colorant red organic pigment (Seika First Red LR-1)
2.15 (manufactured by Dainichiseika) were heat-kneaded, cooled, and then crushed using a jet pulverizer to obtain a red toner having a particle size of 10 to 15 μm.

Example 2 As a binder resin, 100 parts by weight of styrene-acrylic copolymer resin (Priolitem 0, manufactured by Gutdeyer),
4 parts by weight of quaternary ammonium salt (Bontron ?-51, manufactured by Orient Kagaku Co., Ltd.), 4 parts by weight of stearic acid, and 5 parts by weight of backing phthalocyanine pigment (Linol Blue 8M manufactured by Toyo Ink Co., Ltd.) were kneaded with heat, and then cooled. After that, a blue toner having a corner particle size of 10 to 15 μm was obtained by using a jet pulverizer.

Example 3 Epoxy resin (Evoto) YDO14 as a binder,
(manufactured by Tobu Kasei Co., Ltd.) 100 parts by weight, quaternary ammonium salt (
3 parts by weight of Bontron P-51 (manufactured by Orient Chemical Co., Ltd.), 3 parts by weight of stearic acid, and 5 parts by weight of carbon black (Mitsubishi Carbon #40, manufactured by Mitsubishi Chemical Co., Ltd.) were heated, cooled, and then shredded by a jet pulverizer. A black toner with a particle size of 10 to 15P was obtained.

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

Comparative Example 2 A red toner was obtained in the same manner as in Comparative Example 1, except that the polyamine shown in Japanese Patent Publication No. 59-41184 (Bontron AFP-8 manufactured by Orient Chemical Co., Ltd.) was used as a charge control agent.

Next, 5 parts by weight of each of the above toners were mixed and stirred with 100 parts by weight of fluororesin-coated iron powder carrier (T8V-052 manufactured by Nippon Tetsuko Co., Ltd.) to prepare a developer. The stability of the charge and the stability of the charge in a high temperature atmosphere were investigated. The charge was measured using a blow-off powder charge measuring device (manufactured by Tobu Chemical Co., Ltd.). The data are shown in the following table, and it can be seen that the toner of Example 9 is superior. Note that although the P]'O copying machine has a zinc oxide photoreceptor, there is no significant difference in the results even if a copying machine with a QPO photoreceptor is used.

1) Long run; Stability in P (Effects of the invention) The present invention is clear from the above comparative tests. It also has stable image characteristics and can obtain particularly clear images. ζ: Even when making continuous copies or copying 5,000 sheets, it is almost clear even when it is placed in a very humid environment such as during the rainy season. It is possible to provide a toner that exhibits excellent effects such as being able to obtain clear images and being less likely to cause background smudges compared to comparative examples.

Claims (2)

[Claims] (1) Toner for developing electrostatic images characterized by containing a quaternary ammonium salt and stearic acid (2) Claims 1 to 5 parts by weight of quaternary ammonium salt to 100 parts by weight of binder resin, and 25 to 150 parts by weight of stearic acid to 100 parts by weight of quaternary ammonium salt. Toner for developing an electrostatic image according to item 1