JPH0424646A - Electrostatic latent image developing toner - Google Patents

Abstract

PURPOSE:To contrive the stabilization of triboelectrification being a problem on a 2-component developing system by incorporating a coloring agent and an antimony-dopped tin oxide in a resin. CONSTITUTION:The coloring agent and the antimony-dopped tin oxide are added to the resin, and mixed, and then a developer is prepared. In such a manner by adding the antimony-dopped tin oxide (SnO2), the triboelectrification in the 2-component developing system can be stabilized and the quantity of an obtained image is always improved and the excellent quality in particular as a color toner can be offered and without scratching the surface of a photosensitive body of OPC, etc., the supply of the excellent color toner or the developer without being stained with the carrier is available.

Description

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

(Prior art) Development methods in the fields of electrophotography, electrostatic recording, etc. have conventionally used toner containing a charge control agent, finely pulverized to 5 to 20 μm, and a carrier such as ferrite powder or iron powder. A dry development method using a so-called two-component developer prepared by mixing is generally known.

(Problem to be Solved by the Invention) However, in the two-component method, the amount of triboelectric charge of the toner and carrier varies depending on the increase in the number of sheets to be developed and the environmental conditions. In other words, as the number of sheets to be developed increases, the amount of triboelectricity of the toner and carrier increases, and the amount of triboelectricity is larger in a low temperature and low humidity environment than in a high temperature and high humidity environment. As the number of sheets developed in a low-temperature, low-humidity environment increases, the amount of triboelectric charge increases, resulting in a significant decrease in image density, increased fogging, and carrier fly-off where carrier adheres to the electrostatic image support. However, undesirable situations such as damage to the surface of the photoreceptor and the fixing roller may occur.

The purpose of the present invention is to provide a charge control agent that improves the instability of triboelectric charging, which is a problem in the above-mentioned two-component development system, and that enables stable images to be obtained even under various environmental changes. There is.

(Means for Solving the Problem) To achieve this objective, antimony-doped tin oxide (Sn02) was added.

(Function) With this configuration, triboelectric charging properties in a two-component development system can be stabilized.

(Examples) Hereinafter, the present invention will be explained in more detail with reference to Examples. Note that the present invention is not limited to these examples. Hereinafter, all parts of the formulation are by weight.

・Example 1゜・Styrene-acrylic acid ester resin 100B (product name Hymer TBL-5fl)e, manufactured by Sanyo Chemical Co., Ltd.)・
4 parts of low molecular weight polypropylene (trade name: Heathyl 55θ-P, manufactured by Sanyo Chemical Co., Ltd.)
2 parts of charge control agent (product name: Citron E-84, manufactured by I-Rient Chemical Industry Co., Ltd.), 1 part of antimony-doped tin oxide (product name: Tyberi 5N-1081, manufactured by Ishihara Sangyo Co., Ltd.).
Rhodamine dye (C, 1,5olvent ed 49) 4 parts (trade name Aizen SOT Pink-1, manufactured by Sakudogaya Chemical Industry Co., Ltd.) The above materials were uniformly dispersed with a Henschel mixer, and the dispersion was mixed with a twin-screw presser, etc. After cooling, the mixture was pulverized using a jet mill or the like, and a classified product having an average particle size of 11 μm was obtained using a classifier. To this classified product, 0.3% by weight of hydrophobic silica (trade name R972, manufactured by Nippon Aerosil Co., Ltd.) was externally added using a Henschel mixer to obtain a magenta toner of the present invention. Transfer this toner to a ferrite carrier (product name FL-150,
(manufactured by Powder Chick Co., Ltd.) to prepare a developer. When the amount of triboelectric charge of this developer was measured by the blow-off method, it was found that:
-20, OμC/g. Using this developer, 20 consecutive prints were performed in various environments using a laser printer (trade name: KX-P4450, manufactured by Matsushita Electric Industrial Co., Ltd.), and the amount of triboelectric charge and print density were measured. The following three environments were selected. They are low temperature and low humidity (temperature 10°C, humidity 20% RH), normal temperature and normal humidity (temperature 20°C, humidity 60% RH), and high temperature and high humidity (temperature 32.5°C, humidity 80% RH). For comparison with the conventional method, toner production, developer production, and testing were conducted under the same conditions as above, except that antimony-doped tin oxide was not used. The test results of the conventional method and this example are summarized in FIGS. 1 and 2. FIG. 1 is a diagram showing the relationship between the number of developed sheets and the amount of triboelectric charge, and FIG. 2 is a diagram showing the relationship between the number of developed sheets and print density. In FIG. 1, the horizontal axis shows the number of developed sheets, and the vertical axis shows the amount of triboelectric charge. In FIG. 1, lines 1.2.3 indicate the characteristics when unexamined toners are used, line 1 is for high temperature and high humidity, line 2 is for normal temperature and humidity, and bond 3 is low temperature and low humidity. Also 4,5.6
are lines showing characteristics when conventional toners are used; line 4 is for high temperature and high humidity, line 5 is for normal temperature and normal humidity, and line 6 is for low temperature and low humidity. As can be seen from FIG. 1, in this example, the amount of triboelectric charge hardly changes even when the number of sheets to be developed increases, and it can be seen that the amount of triboelectricity is almost constant. However, in the conventional case, it can be seen that as the number of developed sheets increases, the amount of triboelectric charge gradually increases. Further, as the number of developed sheets increases, the variation in each environment becomes larger. In FIG. 2, lines 7, 8, and 9 indicate the characteristics when the toner of this example is used. Line 7 is for high temperature and high humidity, line 8 is for normal temperature and humidity, and line 9 is for when the toner is used. is low temperature and low humidity. Lines 10, 11, and 12 indicate the characteristics when conventional toners are used. Line 10 is for high temperature and high humidity, line 11 is for normal temperature and humidity, and line 12 is for low temperature and low humidity. It is. As can be seen from FIG. 2, in this example, the print density remains almost constant even if the number of sheets to be developed increases. However, with the conventional method, the print density becomes thinner in all environments as the number of developed sheets increases.It can also be seen that the dispersion increases as the number of developed sheets increases in each environment. The amount of triboelectric charge during running was measured by the blow-off method, and the density was measured using a Maches reflection densitometer.

・Example 2゜・100 parts of saturated polyester resin (trade name) Polyester, manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd.・4 parts of low molecular weight polypropylene (trade name: Viscole 660-P, manufactured by Sanyo Chemical Co., Ltd.)
・Charge control agent 4 parts (trade name: Phontron E-84 manufactured by Rient Kagaku Kogyo Co., Ltd.) -7 Talocyanine pigment (C.1.Pig
ment Blue Is3) 4 parts (trade name: KET BLUE 1 (l16, manufactured by Dainippon Ink Kaji Kogyo Co., Ltd.) The above material was treated in the same manner as in Example 1 to obtain an average particle size of 1.
A 1 μm classified product was obtained. This classified product contains 0.3% by weight of hydrophobic silica (trade name R972, manufactured by Nippon Aerosil Co., Ltd.)
and 1.0% by weight of antimony-doped tin oxide (
A cyan toner of the present invention was obtained by externally adding the product (trade name: Tybake SN-100, manufactured by Ishiya Sangyo Co., Ltd.) using a Henschel mixer. Example 1. When a developer was made with the same carrier and the amount of triboelectric charge was measured, it was -23.0μC/
It was g. This toner was used under the same conditions as in Example 1.
0K was printed, but under various environments,
The amount of triboelectric charge of the toner of the present invention showed little variation among various environments (and the transition of the amount of triboelectricity during running was also stable, showing good print density.For comparison, antimony-doped oxidation When producing toner, producing developer, and conducting tests under the same conditions as above except that tin was not used, the resulting images changed significantly as the number of running sheets increased, and there were large variations between each environment. However, the developer was not suitable for practical use.

・Example 3.

- Saturated polyester resin 100 parts (trade name: Polyester-HI"32θ, manufactured by Nippon Gosei Kagaku Kogyo Co., Ltd.) - Low molecular weight polypropylene 3 parts (trade name: Hiskol 5e, manufactured by Sanyo Chemical Co., Ltd.) - Charge control agent 4 parts (trade name) TP-302, manufactured by Odugaya Chemical Industry Co., Ltd.)・
C. 1. Solvent Yellow 2
Part 13 (Product name: Helifast Yellow 3120
, manufactured by Orient Kaji Kogyo Co., Ltd.) The above materials were used in Example 1. It was treated in the same manner as above to obtain a classified product with an average particle size of 11 μm. Q. Q weight%
Antimony-doped tin oxide (trade name: Tybake SN-1 00, manufactured by Ishiya Sangyo Co., Ltd.) was externally added using a Henschel mixer to obtain the yellow toner of the present invention. A developer was prepared from this toner using the same carrier as in Example 1, and the amount of triboelectric charge was measured, and it was found to be +21.0 μC'g. This toner is a positively charged toner, and this toner was used in Example 1. 20 was printed under the same conditions by modifying the Caesar printer used in 2010. Similarly, in various environments, the amount of frictional charge of the toner of the present invention showed little variation between various environments and during running. Stable results were obtained with respect to the change in triboelectric charge amount, and good print density was obtained. For comparison purposes, toner production, developer production, and testing were conducted under the same conditions as above, except that antimony-doped tin oxide was not used, and the resulting images changed significantly as the number of running sheets increased. In addition, there were large variations between environments, and the developer was not suitable for practical use.

The above-mentioned wood examples can be used for both positively charging and negatively charging properties.Although the above-mentioned material is pale gray, it is transparent, so it shows a suitable charge control effect and color tone for color toners. It is possible to provide clear color toner without damage.

Note that antimony-doped tin oxide may be contained in the toner by either internally adding it to the toner or externally adding it to the surface of the toner particles. The blending amount is preferably in the range of 0.3 to 10.0 parts by weight per 100 parts by weight of the resin in the toner (if added internally, it is preferably in the range of 0.3 to 10.0 parts by weight per 100 parts by weight of the resin, and if added externally to the toner particle surface, per 100 parts by weight of the toner composition). The amount is preferably in the range of 0.01 to 2.00 parts by weight.If it is less than the above range, the triboelectric charging stability of the toner will be impaired, and if it is more than that, it will not be possible to secure a sufficient amount of charge. As the binder resin of the present invention, all known binder resins can be used.For example, polystyrene, poly-α
- Methylstyrene, chloropolystyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer polymer, styrene-acrylic ester copolymer, styrene-methacrylic ester copolymer,
Styrenic resins (styrene or styrene-substituted monopolymers or copolymers containing styrene or styrene substitutes) such as styrene-α-methyl chloroacrylate copolymer, styrene-acrylonitrile-acrylic acid ester copolymer, epoxy resin, urethane-modified epoxy Resin, silicone-modified epoxy resin, polyester resin, vinyl chloride resin, styrene-vinyl acetate copolymer, rosin-modified maleic acid resin, phenyl resin,
Polyethylene, polypropylene, iomer resin, polyurethane resin, silicone resin, ketone resin, ethylene-ethyl acrylate copolymer, xylene resin, polyhinyl butyral resin, terpene resin, phenol resin,
Aliphatic or alicyclic hydrocarbon resins can be used alone or in combination. Particularly preferable for this example are:
There are styrene-acrylic ester resins, styrene-methacrylic ester resins, and polyester resins. Furthermore, when the present developer is used as a two-component toner, known carriers can be used. For example, surface oxidized or unoxidized iron or iron and nickel, copper, zinc,
Metals such as cobalt, manganese, chromium, rare earths, alloys thereof, or oxides and ferrites can be used. Moreover, those whose surfaces are coated with various resins can also be used. Depending on the case, a fluidity modifier such as colloidal silica may be added to the developer in an amount of 0.01 to 6.00% by weight (particularly preferably 0.1 to 1% by weight) based on the toner.
．． 0% by weight) may be added.

(Effects of the Invention) The present invention provides antimony-doped tin oxide (S).
By adding n02), it is possible to stabilize the triboelectricity in the two-component development system, so the quality of the images obtained is always good, and especially as a color toner, it can provide very excellent quality. It is something. A predetermined density can be maintained, the surface of a photoreceptor such as an OPC will not be damaged, and a good color toner or developer without carrier contamination can be supplied.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the relationship between the number of developed sheets and the amount of triboelectric charge, and FIG. 2 is a diagram showing the relationship between the number of developed sheets and print density. 1.2.3... line 4.5.6... line 7.8.9... line 10.11.12... line

Claims (1)

[Claims] A toner for developing electrostatic latent images characterized by containing a resin, a pigment, and tin oxide doped with antimony.