JPH04199155A - Non-magnetic one-component toner and image forming method - Google Patents

Abstract

PURPOSE:To prevent the lowering of image density by a reduction of the amt. of a toner transferred to a toner carrier due to the deterioration of the flowability of the toner by specifying the volume average diameter of the toner and the content of particles of a prescribed diameter or below. CONSTITUTION:The volume average diameter of a toner is regulated to 10.0-13.0mum and the content of particles of <=5mum diameter to 1.0-4.0vol.%. The toner may be produced by blending a colorant such as carbon black with a resin binder such as a styrene-n-butyl acrylate copolymer, a releasing agent such as low molecular polypropylene wax and an electric charge controlling agent such as quat. ammonium salt.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to electrophotography, non-magnetic monocomponent toner for developing electrostatic latent images in electrostatic printing, and an image forming method. Photography method Electrostatic printing method An electrostatic latent image formed in electrostatic recording method (generally developed with toner, then transferred to paper and visualized through a fixing process) A method of developing an electrostatic latent image. This is a process in which toner particles are charged and then adhered to a photoreceptor with an electrostatic latent image by electrostatic attraction to make it visible.The two-component development method in which toner particles are mixed with something called a carrier is generally used. There is a one-component development method that is used alone.The former development method is a method in which the toner and carrier are mixed and stirred and the toner is charged by mutual frictional electrification.A cascade development method that uses a glass beads carrier and an iron powder carrier are used. Although the magnetic brush development method is well known, in any of these methods, the toner in the developer is consumed sequentially in the development process, so toner is replenished during development and the ratio of toner to carrier in the developer is constantly maintained. It is necessary to maintain it within a certain range. Also, depending on the carrier used (for example, if an iron powder carrier is used), the oxidation of the surface may cause deterioration and change the triboelectric charging behavior between the toner and the toner. The triboelectrification series of the oxidized carrier and the triboelectrification series of the carrier that does not undergo oxidation ζ
Due to misalignment, the charged polarity of the carrier may show the opposite polarity to the desired polarity. Similarly, when using a ferrite-based coated carrier, the conditions for coating the ferrite are extremely difficult and uniform. This may cause undesirable carrier adhesion to the image, toner adhesion to non-image areas, so-called fog, or a decrease in density due to toner charge-up. 4. Two-component development as described above. In order to avoid the drawbacks associated with this method, various developing methods using toner alone have been proposed, but many of these methods have been devised using magnetic components, which use magnetic force to transport toner. However, it is difficult to disperse the magnetic material in the toner, causing clutter, toner flying, and a decrease in density.In addition, the toner carrier that transports the toner is equipped with a magnet, which reduces the weight of the small plate, which is an advantage of single-component developing devices. becomes difficult. Therefore, a fur brush development method in which a non-magnetic monocomponent toner is made into a thin layer using an elastic member using a fur brush as a developer carrying roller member is considered to be suitable for reducing the size and weight.

An example of the conventional developing method described above will be described below with reference to the drawings.

Figure 1 is a cross-sectional view of a conventional general developing device.
In the figure, 1 is an elastic member made of resin with rubber elasticity. 2 is a fur brush containing carbon black in resin fibers; 3 is a toner carrier having a cylindrical metal compound or metal oxide surface treated; 4 is a stirring device; 5 is a toner carrier It is a storage section. 6 is a non-magnetic one-component toner that is not colored in the resin. Charge control template. The operation of the non-magnetic one-component toner and image forming method constructed as above, even if it contains a fluidizing agent etc., will be explained below. First, the toner 6 in the toner storage section 5 is supplied to the fur brush 2 by the stirring device.Then, the fur brush 2 charges, transports, and supplies the toner, and the toner moves to the toner carrier 3.Next, the elastic member l The electrostatic latent image carrier is visualized by applying a DC bias.

Problems to be Solved by the Invention However, with the above configuration, strong stress is applied to the toner when the toner is made into a thin layer by the toner elastic member, and the fluidizing agent on the surface of the toner is buried inside the toner, resulting in poor fluidity. In view of the above problems, the present invention provides a non-magnetic single-component toner and an image forming method that do not cause density reduction. Means for Solving the Problems In order to solve the above problems, the non-magnetic one-component toner and image forming method of the present invention include means for forming a thin layer of toner on a toner carrier using an elastic member, and charging of the toner. A non-magnetic one-component toner used in a developing device comprising a means for transporting and supplying the toner with a developer carrying roller member, and a means for developing the toner onto an electrostatic latent image holding member holding an electrostatic latent image using a DC bias. and a volume average diameter of 10.0 μm to 13.0 μm
The present invention provides a non-magnetic one-component toner and an image forming method characterized in that the volume content of particles having a diameter of 5 μm or less is 1°0 to 4.0 wt%. Due to the presence of toner with a diameter of 5 μm or less, the elastic member acts as a buffer when forming a thin layer of toner, and the stress applied to the toner reduces the embedding of silica into the toner, reducing the fluidity of the toner. Example: Examples of the present invention will be described below. It should be noted that the present invention is not limited to these examples.The non-magnetic one-component toner of the present invention uses carbon black as a coloring agent. Known toner resins include styrene-acrylic acid resins, styrene-dendritic styrene-butadiene resins, epoxy resins, polyester resins, low-molecular polyethylene wax as a release agent, low-molecular polypropylene wax, etc. as a charge control agent, and positively charged toners as charge control agents. as quaternary ammonium salt
Nigrosine-based electron-donating color point Chlorinated paraffin, monoazo-based dye metal complex salts, etc. are used as negatively charged toners.

Example 1 The toner was prepared as follows: carbon black (MA-100 manufactured by Mitsubishi Kasei), 5 wt% styrene-n-butyl acrylate resin (80/20), 90 wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical), 3 wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 11.0μm
A classified product containing 1.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example, a copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric Co., Ltd.) to evaluate the image density. D.
=1. Even after printing 1oooo sheets with 44, 1. D.
=1. Example 2 A high image density of 41 or higher can be maintained and t can be maintained.The toner was carbon black (MA, -100 manufactured by Mitsubishi Kasei) prepared as follows.5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550P made by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 11.0μm
A classified product containing 2.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example which was obtained by externally adding the toner, a copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric) to evaluate the image density.9 The initial density was 1. 46 to 1
I even after printing 0000 sheets.

D, Example 3 in which a high concentration of -1,43 or higher was maintained.The toner was prepared as follows:μ Carbon black (MA-100 manufactured by Mitsubishi Kasei) 5wt% styrene-
n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550F manufactured by Sanyo Chemical Co., Ltd.) 3wt% quaternary ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture consisting of the above composition was melt-kneaded at 130°C with a roll mill. death
After cooling, it is coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and air classified to give a volume average particle size of 11.0 μm and 5 μm.
Obtaining a classified product containing 4.0 wt% of toner of m or less,
Furthermore, using the non-magnetic single-component toner described in the following example, which was obtained by externally adding 0.5 wt% of hydrophobic silica using a Henschel mixer, a copying test was conducted using a digital copying machine FP-C (manufactured by Kenko Denki). The initial density when evaluating the image density was 1.
D, =1. 1. Even after printing 10,000 sheets with 45.
D, =1. Example 4 in which a high concentration of 42 or higher was maintained The toner was prepared as follows: Carbon black (MA-100 manufactured by Mitsubishi Kasei) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (viscol) 550P made by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 10.0μm
A classified product containing 1.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example, a copying test was carried out using a digital copying machine FP-C1 (manufactured by Kenko Denki) to evaluate the image density, and the initial density was 1. ．． D.
=1. 46] 0000 sheets El] Even after printing 1. D.
=1. Example 5 The toner was carbon black (MA, -100 manufactured by Mitsubishi Kasei) prepared as follows: 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (80/20) Viscole 550P (manufactured by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 in 10.09m
A classified product containing 2.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
A copying test was conducted using a digital copying machine FP-CI (manufactured by Kenko Denki Co., Ltd.) using a non-magnetic mono-component toner described in the following examples, which was obtained by externally adding the toner, and the initial density was 1. 46
Even after printing 1oooo sheets.

A high concentration of D,=1.45 or higher can be maintained fQ.

Example 6 The toner was prepared as follows: Carbon black (MA-100 manufactured by Mitsubishi Kasei) 5 wt% styrene-n-butyl acrylate resin (80/20) 90 wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical) 3 wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 10, 5 at 0 μm
A classified product containing 4.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example, a copying test was conducted using a digital copying machine FP-C1 (manufactured by Kenko Denki Co., Ltd.) to evaluate the image density. 1. D.
=1. 1. Even after printing 10,000 sheets with 45. D.
=1. A high concentration of 45 or more continued.
n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical Co., Ltd.) 3wt% quaternary ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture consisting of the above composition was melt-kneaded at 130°C with a roll mill. After cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and air classified to give a volume average particle size of 13.0 μm.
A classified product containing 1.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example which was obtained by externally adding the toner, a copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric) to evaluate the image density. l)
, -1.47 even after printing 10,000 sheets. D.
=1. , Example 8 where a high image density of 44 or higher continued.The toner was carbon black (MA-100 manufactured by Mitsubishi Kasei) prepared as follows.5wt% styrene-n-butyl acrylate resin (80/20)90wt% polypropylene wax (viscol). 550P made by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P'-51 manufactured by Orient Chemical Co., Ltd.) A mixture consisting of 2wt% self-composition was melted and mixed at 130℃ with a roll mill. After cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume was determined by air classification. Average particle size 13.0μ
A classified product containing 2.0 wt% of toner with a particle diameter of 5 μm or less was obtained using a Henschel mixer.
Using the non-magnetic one-component toner described in the following examples, a copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric) to evaluate the image density. 1.46
Even after printing 10,000 sheets, I still get it.

Example 9 in which a high concentration of D, = 1.44 or more can be maintained The toner was carbon black prepared as follows (MA-100 manufactured by Mitsubishi Kasei) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt % polypropylene wax (Viscol 550P manufactured by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. A classified product containing 4.0 wt% of toner of 13.0 μm and 5 μm or less was obtained, and further 0.5 wt% of hydrophobic silica was obtained using a Henschel mixer.
A copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric Co., Ltd.) using the non-magnetic mono-component toner described in the following example, in which the toner was obtained by adding % externally.The initial density was 1. D.
=1. 1. Even after printing 10,000 sheets with 45. D.
A high concentration of −1,46 or more can be maintained and t can also be maintained in Comparative Example 1. The toner was prepared as follows: 8 carbon black (MA-100 manufactured by Mitsubishi Kasei) 5 wt% Styrene-n-butyl acrylate resin (80/20) 90 wt% Polypropylene wax (Viscol 550P manufactured by Sanyo Chemical Co., Ltd.) 3 wt% Quaternary ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2 wt% A mixture consisting of the above composition was melted and kneaded at 130°C in a roll mill, and after cooling, it was roughly pulverized with a cutter mill and then jetted. Finely pulverized with a mill and air classified with a volume average particle size of 11.0 μm.
A classified product containing 0.5 wt% of toner of μm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
A copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric Co., Ltd.) using a non-magnetic mono-component toner described in the following examples which was obtained by externally adding toner, and the initial density was 1. D.
=1. The force was 42<1 after printing 4000 sheets.
D, Comparative Example 2 in which the image density decreased to -1,19 The toner was prepared as follows: 9 carbon black (Ml-100 manufactured by Mitsubishi Kasei) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene Wax (Viscol 550P manufactured by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. A classified product containing 5.0 wt% of toner of 11.0 μm and 5 μm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following examples, a copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric), and the image density was evaluated. ．．
D, =1. 29 and Low Kasai Comparative Example 3 The toner was prepared as follows: 9 carbon black (MA-100 manufactured by Mitsubishi Chemical) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. A classified product containing 5 wt% of toner with a diameter of 10.0 μm and 5 μm or less was obtained, and further mixed with 0.5 wt% of hydrophobic silica using a Henschel mixer.
A copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric Co., Ltd.) using a non-magnetic monocomponent toner described in the following example in which a toner was obtained by externally adding wt%, and the initial density was 1. ．． D.
=1. The force was 41 (1. after printing 4000 sheets)
D, =1. Comparative Example 4 in which the image density decreased to 18. The toner was carbon black prepared as follows (MA-100 manufactured by Mitsubishi Chemical Co., Ltd.), 5 wt% styrene-n-butyl acrylate resin (80/20), 90 wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical Co., Ltd.). ) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 10.0μm
A classified product containing 5.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic single-component toner described in the following examples, a copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric), and the image density was evaluated.
D, =1. Comparative example 5, which was low at 26.Is the toner made as follows? , :,.

Carbon black (MA, -100 made by Mitsubishi Kasei) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550P made by Sanyo Kasei) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 13.0μm
0, . A classified product containing 5wt% of hydrophobic silica was obtained, and further 0.5wt of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following example, a copying test was conducted using a digital copying machine FP'-CI (manufactured by Matsushita Electric Co., Ltd.) to evaluate the image density. 1. D
, =1. The force was 44 (1 after printing 4000 sheets)
．． D, =1. Comparative Example 6 in which the image density decreased to 22. The toner was prepared as follows. 550P made by Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-5) manufactured by Orient Chemical Co., Ltd. 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, cooled, coarsely pulverized in a cutter mill, then finely pulverized in a jet mill, and then air-classified into volume-average particles. A classified product containing 5.0 wt% of toner with a diameter of 13.0 μm and 5 μm or less was obtained, and 0.5 wt% of hydrophobic silica was further added using a Henschel mixer.
Using the non-magnetic one-component toner described in the following examples, a copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric Co., Ltd.) to evaluate the image density. 1. D.
-1,28 and low and 9 Comparative Example 7 The toner was prepared as follows: 9 carbon black (MA-100 manufactured by Mitsubishi Kasei) 5 wt% styrene-n-butyl acrylate resin (80/20) 90 wt% polypropylene wax (Viscol 550P Sanyo Chemical) 3wt% 4th
Grade ammonium salt (P-51 manufactured by Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C in a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume average particle size was determined by air classification. 5 at 9.0μm
A classified product containing 2°0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was obtained using a Henschel mixer.
Using the non-magnetic mono-component toner described in the following example, which was obtained by externally adding toner, a copying test was conducted using a digital copying machine FP-C1 (manufactured by Matsushita Electric), and the image density was evaluated. ,D,
=1. Comparative Example 8 The toner was made as follows: Carbon black (MA-100 manufactured by Mitsubishi Chemical) 5wt% styrene-n-butyl acrylate resin (80/20) 90wt% polypropylene wax (Viscol 550P manufactured by Sanyo Chemical) 3wt % Quaternary ammonium salt (P-51 Orient Chemical Co., Ltd.) 2wt% A mixture having the above composition was melt-kneaded at 130°C with a roll mill, and after cooling, it was coarsely pulverized with a cutter mill, then finely pulverized with a jet mill, and the volume was determined by air classification. 5 with an average particle size of 14.0 μm
A classified product containing 2.0 wt% of toner of µm or less was obtained, and then 0.5 wt% of hydrophobic silica was added using a Henschel mixer.
Using the non-magnetic single-component toner described in the following example, which was obtained by externally adding toner, a copying test was conducted using a digital copying machine FP-CI (manufactured by Matsushita Electric), and the image density was evaluated. ．．
D. -1,26 Effects of the Invention As described above, the present invention has a means for forming a thin layer of toner on a toner carrier using an elastic member, and a developer carrying roller member for charging, transporting and supplying the toner. A non-magnetic one-component toner for use in a developing device comprising means for developing the toner onto an electrostatic latent image holding member holding an electrostatic latent image with a direct current bias, the toner having a volume average diameter of 10 .0 μm to 13.0 μm, and 5 μm
The non-magnetic one-component toner and the image forming method are characterized in that the volume content of particles of 5 μm or less is contained by an elastic member. It acts as a buffer when forming a thin layer, and the stress applied to the toner reduces the embedding of silica into the toner, resulting in stable images with an image density of 1.4 or higher without reducing the fluidity of the toner. I can do it.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a conventional general developing device, which includes: elastic member, 2: fur brush, 3:
Toner carrying capacity 4... Stirring device 5... Number of toner storage 6 Non-magnetic one-component toner. ¥1 (7

Claims (2)

[Claims] (1) A means for forming a thin layer of toner on a toner carrier using an elastic member, a means for charging, transporting and supplying the toner with a developer carrying roller member, and a means for holding an electrostatic latent image on the toner. A non-magnetic one-component toner used in a developing device comprising means for developing an electrostatic latent image holder with a DC bias, the toner having a volume average diameter of 10.0 μm to 13 μm.
．． A non-magnetic one-component toner characterized in that the particle size is 0 μm and the volume content of particles of 5 μm or less is 1.0 to 4.0 wt%. (2) means for forming a thin layer of toner on a toner carrier using an elastic member; means for charging, transporting, and supplying the toner with a developer carrying roller member; and means for holding the toner in an electrostatic latent image. In a developing device comprising a means for developing an electrostatic latent image holder with a direct current bias, the volume average diameter 1
0.0μm~13. An image forming method characterized by using a non-magnetic one-component toner having a particle size of 0 μm and a volume content of 1.0 to 4.0 wt % of particles having a size of 5 μm or less.