JPH02153362A - Developing method using one-component toner - Google Patents

Abstract

PURPOSE:To stabilize tribo-electrostatic charge against long time uses and environmental changes by adding a specified organic metal complex salt as a negative charge controller to the toner. CONSTITUTION:An electrostatic latent image is developed by using the one- component toner containing as the negative charge control agent the organic complex salt of formula 1 in which each of X1 and X2 is H, lower alkyl, or the like; each of m and m' is 1, 2, or 3; each of R1 and R3 is H, 1 - 18C alkyl, or the like; each of n and n' is 1, 2, or 3; each of R2 and R4 is H or nitro; and A<+> is an H or Na ion or the like. In this toner, the compound of formula II and the like can be used for the complex salt of formula 1, and pigments, such as carbon black, and dyes can be used for the colorant, and styrene type copolymers, such as styrene-n-bytyl methacrylate, and the like can be used as the binder resin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a one-component developing method for developing an electrostatic latent image using a one-component toner containing a specific negative charge control agent.

[Prior art]

There are two methods for developing an electrostatic latent image formed on an electrostatic latent image carrier such as an electrophotographic photoreceptor and an electrostatic recording medium: a method using a liquid developer (wet development method), and a method using a liquid developer (wet development method); A method (dry development method) using a toner in which a colorant is dispersed or a one-component type or two-component type dry developer in which this toner is mixed with a solid carrier is generally adopted. Although each of these methods has its advantages and disadvantages, the dry development method is currently widely used.

By the way, in the above-mentioned toner, dye and dye are simply added to the binder resin.
Since desirable charging properties cannot be obtained by simply dispersing a coloring agent such as a pigment, an appropriate amount of a charge control agent is usually added thereto. Typical examples of conventional charge control agents include (i) agents that impart a positive charge to the toner, such as nigrosine oil-soluble dyes, quaternary ammonium salts, azine dyes having alkyl groups, basic dyes, and Dye lakes and the like can also be used as substances that give a negative charge to (ii))-ner, such as chromium-containing monoazo complexes, chromium-containing salicylic acid compound complexes, and chromium-containing organic dyes (copper phthalocyanine green, chromium-containing monoazo complexes).
Examples include metal-containing dyes such as. However, although toners containing such conventional charge control agents initially exhibit good development characteristics, when used for a long time, the performance of the charge control agent deteriorates, and as a result, the triboelectric charging properties of the toner deteriorate, resulting in filming on the photoreceptor. Inconvenient phenomena are often observed. This is because conventional charge control agents tend to deteriorate or decompose easily due to mechanical thermal shock and friction during the thermal kneading process used in toner production, or environmental changes such as temperature and humidity conditions, resulting in lack of stability. This is due to this.

In particular, a developing device equipped with a toner transport member, a toner layer thickness regulating member, and a toner replenishment auxiliary member (however, the toner replenishment auxiliary member and the toner transport member, and the toner layer thickness regulation member and the toner transport member are in contact with each other). In the one-component development method, in which development (copying) is carried out using a one-component toner made into a thin layer using a single-component toner, fluctuations in the triboelectric charging properties of the toner greatly affect the ability to form a thin toner layer, causing image deterioration. Something happened. In any case, most of the charge control agents that have been proposed so far do not have the desired performance over a long period of time.

[Problem to be solved by the invention]

The purpose of the present invention is to use a one-component toner containing a negative charge control agent that can maintain the desired performance without degrading the toner's triboelectricity due to long-term use or environmental changes. It is an object of the present invention to provide a one-component developing method capable of forming an image as good as the image.

[Structure and operation of the invention]

The one-component developing method of the present invention uses a toner conveying member.

Equipped with a toner layer thickness regulating member and a toner replenishment assisting member,
In addition, the colorant, the binder resin, and the positive or negative charge control are thinned using a developing device in which the toner replenishment auxiliary member, the toner transport member, and the toner layer thickness regulating member and the toner transport member are in contact with each other. In a one-component developing method, in which a one-component toner containing an agent as a main component is supplied to the surface of an electrostatic latent image carrier to develop the latent image, the load controlling agent in the toner is a general formula [wherein, and x2 may be the same or different and represent a hydrogen atom, a lower alkyl group, a lower alkoxy group, a nitro group or a halogen atom, 1m and m' represent an integer of 1 to 3, and R and R3 may be the same or different. Hydrogen atom, C~1. represents an alkyl, alkenyl, sulfonamide, mesyl, sulfonic acid, carboxy ester, hydroxy, C□~, 6 alkoxy, acetylamino, benzoylamino group, or halogen atom, and n and n' are integers of 1 to 3. In the formula, R2 and R4 represent a hydrogen atom or a nitro group, and 80 represents a hydrogen ion, sodium ion, potassium ion, or ammonium ion. ] It is characterized by using an organometallic complex salt shown in the following.

The negative charge control agent of the above general formula contained in the toner used in the developing method of the present invention can be synthesized by known means. These negative charge control agents may be used alone, in combination of two or more types, or may be used together with other negative charge control agents.

Typical specific examples of the organometallic complex salt of the above-mentioned general formula used as a negative charge control agent include the following.

(Hereinafter, blank spaces) The toner used in the developing method of the present invention includes a colorant and a binder resin as essential components along with these negative charge control agents. In order to produce such a toner, the above-mentioned components are heat-kneaded together with other additives if necessary, and after cooling, the resulting mass is crushed and classified, as in the conventional method. Here, the amount of negative charge control agent used is determined by the toner manufacturing method that takes into consideration the type of binder resin, the presence or absence of additives, and the dispersion method, and cannot be uniquely limited; 0.1 to 20 parts by weight, preferably 0.1 parts by weight
~10 parts by weight.

If it is less than 0.1 part by weight, the negative chargeability of the toner will be insufficient and it is not practical, and if it exceeds 20 parts by weight, the negative chargeability of the toner will become too large and the fluidity will deteriorate.

This is undesirable because it causes a decrease in transferability, a decrease in image density, etc. The amount of colorant used is usually 10 parts of the binder resin.
1 to 20 parts by weight based on 0 parts by weight, preferably 5 to 1 parts by weight
The amount is about 5 parts by weight.

All the pigments and dyes conventionally used as toner colorants can be used as the colorant used in the present invention.

Specifically, carbon black, lamp black, iron black, ultramarine blue, nigrosine dye, aniline blue, calco oil blue chrome yellow, ultramarine blue, DuPont oil red, quinoline yellow, methylene blue chloride, phthalocyanine blue, phthalocyanine green, and Hansa yellow. G, rhodamine 6C lake, quinacridone, benzidine yellow, malachite green hexalate, oil black, azo oil black, rose bengal, monoazo pigments, disazo pigments, trisazo pigments, and mixtures thereof.

As for the binder resin used in the present invention, all binder resins that have been used hitherto as binder resins for toners can be used. Specifically, polystyrene, polyP-chlorostin,
Monopolymers of styrene and its substituted products such as polyvinyltoluene; styrene-P-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic Acid methyl copolymer 1, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer Copolymer, styrene-butyl methacrylate copolymer, styrene-α-methyl chloromethacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinylethyl ether copolymer, styrene- Vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-
Styrenic copolymers such as isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, and styrene-maleic acid ester copolymer; polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, polyester, polyurethane,
Polyamide, epoxy resin, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, phenolic resin, aliphatic or alicyclic hydrocarbon resin,
Examples include aromatic petroleum resin, chlorinated paraffin, paraffin wax, etc., and these may be used alone or in combination of two or more.

Further, as additives, magnetic powder, hydrophobic silica, titanium oxide, aluminum oxide, etc. can be used.

Next, the method of the present invention will be explained using the developing device shown in FIG.

In the figure, the one-component toner 6 contained in the toner tank 7 is transported by the stirring blade 5 as a toner replenishment auxiliary member.
Sponge roller 4 also serves as a toner replenishment auxiliary member
It is forcibly conveyed and supplied to the top. The toner thus taken onto the sponge roller is conveyed onto the rubber roller 2 as a toner conveying member by the rotation of this roller 4 in the direction of the arrow, and due to friction with this roller 2, electrostatic and physical is adsorbed to. On the other hand, it adhered to the rubber roller 2! - The toner is uniformly formed into a gI layer by the rotation of the roller 2 in the direction of the arrow and the toner layer thickness regulating member, and is triboelectrically charged by the steel elastic blade 3. Next, the thin toner layer on the rubber roller 2 comes into contact with or comes close to the surface of the electrophotographic photosensitive drum 1 serving as an electrostatic latent image carrier, so that a latent image is developed.

It goes without saying that the developing device used in the method of the present invention is not limited to that shown in FIG.

The present invention will be explained in more detail below with reference to Examples. Note that all parts are parts by weight.

Example 1 A mixture consisting of 100 parts of styrene-〇-butyl methacrylate, 10 parts of carbon black, and 3 parts of negative charge control agent (1) was thoroughly stirred and mixed in a Henschel mixer, and then mixed with a roll mill at a temperature of 130 to 140°C for about 30 parts.
After hot kneading for 0 minutes, the mixture was cooled to room temperature.

This mixed material was pulverized and classified to obtain a toner having a particle size of 5 to 10 μm. When this toner was put into a developing device as shown in FIG. 1 and developed (copied), a good image was obtained, and this image quality did not change even after 10,000 continuous copies.

When the charge amount of the toner was investigated using the blow-off method, the initial charge amount was -16.5 μc/g, and after continuous copying, it was -15.1
It was almost the same as μc/g.

In addition, under high humidity environment of 35℃-90%RH and 10℃
Even in a low humidity environment of -15% RH, images equivalent to those obtained in a normal humidity environment were obtained, and no toner filming on the photoreceptor was observed.

Example 2 A toner was prepared in the same manner as in Example 1 except that negative charge control agent (2) was used instead of negative charge control agent (1), and a copy test was conducted. , and even under high temperature and humidity environments and low temperature and humidity environments, good images equivalent to those obtained under normal temperature and humidity environments were obtained.

Example 3 Styrene-2-ethylhexyl acrylate copolymer 1 instead of 8100 parts of styrene-n-butyl methacrylate
A toner was prepared in the same manner as in Example 1, except that 0 parts and 5 parts of polypropylene were used, and negative charge control agent (3) was used instead of negative charge control agent (1). When we conducted a copy test using this toner, we found that there was almost no change in the amount of toner charge, and that even in high-temperature and low-temperature humid environments, images were as good as those copied under normal temperature and humid environments. Obtained.

Example 4 A toner was made in the same manner as in Example 1 except that the negative charge control agent (15) was used instead of the negative charge control agent (1), and a copy test was conducted. As a result, there was almost no change in the toner charge amount. Even under high-temperature and low-temperature and low-humidity environments, images as good as those copied under normal temperature and normal humidity conditions were obtained.

[Function and effect of the invention]

Since the one-component toner used in the present invention contains the above-mentioned specific organic boron compound as a negative charge control agent, it exhibits stable triboelectrification with negative polarity even after long-term use or environmental changes. If continuous copying is performed according to the method of the present invention, an image as good as the initial image can be formed.

[Brief explanation of the drawing]

FIG. 1 is a diagram of an example of an apparatus for carrying out the method of the present invention. 1... Photosensitive drum as an electrostatic latent image carrier 2...
Rubber roller 4 as a toner conveying member... Sponge roller 5 as a toner replenishment auxiliary member... Stirring blade as a toner replenishment auxiliary member Applicant: Ricoh Co., Ltd. Figure 1

Claims (1)

[Scope of Claims] 1. A toner transporting member, a toner layer thickness regulating member, and a toner replenishment auxiliary member are provided, and the toner replenishment auxiliary member and the toner transporting member are in contact with each other, and the toner layer thickness regulating member and the toner transporting member are in contact with each other. The film was made into a thin layer using a developing device that
In a one-component development method in which a one-component toner containing a colorant, a binder resin, and a positive or negative charge control agent as main components is supplied to the surface of an electrostatic latent image carrier to develop the latent image, the load in the toner is As an electric control agent, there are general formulas ▲ mathematical formulas, chemical formulas, tables, etc. m and m' are 1 to
represents an integer of 3, R_1 and R_3 may be the same or different, hydrogen atom, alkyl of C_1 to_1_8,
represents alkenyl, sulfonamide, mesyl, sulfonic acid, carboxy ester, hydroxy, alkoxy of C_1 to C_1_8, acetylamino, benzoylamino group, or halogen atom, n and n' represent integers of 1 to 3, and R_2 and R_4 It represents a hydrogen atom or a nitro group, and A■ represents a hydrogen ion, sodium ion, potassium ion, or ammonium ion. ] A one-component developing method characterized by using an organometallic acid salt represented by the following.