JPS635353A - Electric charge imparting material for developing electrostatic image - Google Patents

Abstract

PURPOSE:To obtain the titled material having an improved electrostatic charge characteristics of a toner by incorporating a bis (diorganotincarboxylic acid salt) dicarboxylic acid salt to at least the surface of the titled material. CONSTITUTION:The carrier type electric charge imparting material is obtd. by dissolving the bis (diorganotincarboxylic acid salt) dicarboxylic acid salt in a solvent, followed by dispersing it, and by dispersing the carrier of iron powders to the obtd. dispersion, followed by agitating it in a ball mill, and subsequently, drying the mixture until the solvent is completely removed, and by disassembling the obtd. weak cohesive material. Thus, the titled material which does not decrease the electrostatic charge and does not disorder a latent image by repeating a development, is obtd. The titled material facilitates the electrostatic charge, without injuring a color tone of the color toner.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field J] The present invention improves the function of imparting charge to toner used for developing electrostatic images in electrophotography, electrostatic recording, electrostatic printing, etc. The present invention relates to a material or member having a shape, that is, a charge-imparting material (here, :h of "material" is used to include a particulate material in addition to a member having a footprint).

[Prior Art] Conventionally, electrophotography methods include U.S. Pat. No. 2,297,891 and Japanese Patent Publication No. 42-23910.
(k, Fk. v Japanese Patent Publication No. 43-24748 +;- Various methods are described in the gazette, etc., but in short, these methods give electrostatic charges like - to the photoconductive insulator layer 1-. , an electrostatic latent image is formed by irradiating the insulating layer with a light image, and then this latent image is developed and visualized using a fine powder called toner using this technology, and if necessary, the powder image is transferred to paper etc. After the image is transferred, it is fixed by heating, pressure, solvent vapor, or the like.

The development methods used in Kadokawa's electrophotography methods are as follows:
Broadly speaking, there are dry development methods and wet development methods. NFF users are further divided into methods using a two-component developer and methods using a -component developer.

For those that succumb to the two-component developing power method, depending on the type of carrier that conveys the toner, there is a magnet that uses an iron powder carrier.
/ }There are brush methods, cascade methods using heat carriers, fur brush methods using fur, etc.

In addition, those belonging to the one-component development method include the powder kraut method, which uses toner particles in a spray state, and the toner particle f
A contact development method (also called contact development or toner development) in which toner particles T are developed by bringing them into direct contact with the electrostatic latent image surface. There are a jumping development method in which an electrostatic latent image is caused to fly toward the latent image surface using an electric field, and a magneto-dry method in which magnetic conductive toner is brought into contact with the electrostatic latent image surface for development.

Toners used in these development methods have traditionally been fine powders in which dyes and pigments are dispersed in natural or synthetic resins. For example, particles obtained by dispersing a colorant in a binder resin such as polystyrene and pulverizing the particles to about 1 to 30 μm are used as toner. Furthermore, magnetic toners containing magnetic particles such as magnetite instead of or in addition to the dyes or pigments described above are used. In the case of a system using a so-called -component developer, the above-mentioned toner is usually mixed with carrier particles such as glass beads and iron powder.

Also, the toner has a polarity depending on the polarity of the electrostatic latent image to be developed.
A positive or negative charge can be changed.

In order to charge the toner, it is possible to use only the tribostatic charging properties of the resin, which is a component of the toner.
In this method, since the toner has low chargeability, the image obtained by development is likely to be foggy and unclear. Therefore, in order to impart desired triboelectric charging properties to the toner, charge control agents such as dyes and pigments that enhance the charging properties are added.

However, in order to impart chargeability to the toner by adding these additives, these additives must be present on the surface of the toner to some extent. Therefore, due to friction between the toners, collision with the carrier, friction with the electrostatic latent image carrier, etc., these additives fall off from the toner surface, contaminating the carrier, etc., and causing damage to the electrostatic latent image carrier, such as photosensitive Contamination of the body belt or drum may occur. As a result, the charging property deteriorates, and as development operations are repeated, the deterioration progresses, resulting in low image density, reduced fine line reproducibility, increased fog, and other practical problems.

The above-mentioned problems can be solved by improving the affinity and dispersibility of the toner's inder and additives such as dyes and pigments that impart chargeability or charge control agents. Surface treatment to increase the toner often results in a decrease in chargeability, and if strong mechanical shear is applied to finely disperse the toner, the proportion of the additive that appears on the toner surface decreases, and the chargeability tends to be insufficient. becomes. For these reasons, there are very few additives that can impart chargeability to toner to a practically satisfactory level.
There are only a few that have been put into practical use. In particular, in order to obtain not only black and white images but also color images, it is preferable that the charge control agent added to the toner be colorless, and in this case, there are almost no practically satisfactory charge control agents.

In view of these circumstances, we aim to achieve the desired t1 characteristic of toner charging not only with toner additives, but also with agents, sleeves, doctor blades, etc. that come into contact with toner during the development process. It has also been proposed to improve the charging characteristics of a toner conveyance, regulation, or rubbing member (unspecified, 1; hereinafter, these are collectively referred to as "charged T material"). In other words, in this specification, the term "charged goo material" refers to a material that comes into contact with the toner during or prior to development, and imparts or assists the charge necessary to the toner for development. A material or member that can be attached to other materials.

In this method of actively charging the toner with the charged γ material, there is almost no need for the toner to contain additives for improving the band characteristics. Substantial revisions to problems can be made. For example, the causes of contamination of carrier particles, photoreceptors, etc. are reduced in a wood-like manner, so that repeated development operations do not reduce the banding properties or disturb the latent image. Furthermore, 912 tones can be easily applied without impairing the color tone of the color toner.

[Problems to be solved by the invention] Charged materials such as carriers, sleeves, and doctor blades must not only have a strong charge imparting ability, but also be durable and able to withstand friction with toner. Must be. For example, it is desired that the carrier be used for a long period of time without being replaced, and the sleeve is required to have the same durability as the main body of the developing machine.

An object of the present invention is to provide a charged material that solves the above-mentioned problems. A further object of the present invention is to provide a charged material that imparts appropriate negative charges to toner.

A further object of the present invention is to provide a charge imparting material whose performance does not deteriorate even after long-term use.

A further object of the present invention is to provide a charge-imparting material that provides images with excellent fine line reproducibility and gradation.

A further object of the present invention is to provide a charge imparting material suitable for charging color toner.

[Means and effects for solving the problems] The present inventors conducted research to achieve the above-mentioned object, and as a result, they arrived at the following invention.

That is, the present invention provides bis(diorganotin carboxylate)
What is the cause of the charge-imparting properties of bis(dionoreganotincarponate) dicarponate, which is a charge-imparting material for electrostatic image development characterized by having dicarpon m salt at least on the surface? Although unknown, S
It is thought that the n-0 bond plays an important role. Therefore, the organo group to which the tin atom is bonded is not particularly limited. However, it is more effective to use an electron-donating group that increases the charge density of the tin atom. Examples include alkyl groups such as methyl group, ethyl group, tert-butyl group, octyl group, and stearyl group, cyclic alkyl groups such as cyclopentyl group, cyclohexyl group, and cyclooctyl group, and derivatives having these as basic skeletons. In addition, although the young F charge density is low T, 7ralkyl groups such as benzyl group and phenethyl group, or phenyl group, naphthyl group, anthryl group, tolyl group, 4-tert-butylphenyl group, p-methoxyphenyl group, Aryl groups such as p-dimethylaminophenyl, (, etc.) or derivatives having these as the basic skeleton can also be used favorably.

Furthermore, any carboxylic acid or dicanoleponic acid can be used as long as it is thermally stable and has low hygroscopicity.

A typical example of the bis(diorganotincarboxylate) dicarponate of the present invention is shown below.

The above compound is applied to the charged lj material as particles having an average particle size of IO = 0.01 gffi, especially 2 to 0.1 ILm, depending on the shape of the charged lj material to be applied. It is preferable to use it for formation.

These compounds can be prepared by dipping, spraying, or dipping a coating solution obtained by dissolving or dispersing it in a solvent or dispersion agent together with a binder resin as necessary onto the base material of the charged material.
% 16 by brushing, etc., or if the base material is in the form of carrier particles, it is mixed with the above-mentioned coating solution by immersion and then dried, or by a fluidized bed of a direct mixture of this and the above-mentioned compound. By methods such as coating,
The charged material of the present invention can be obtained by forming a coating layer of the above compound on the motherboard. Alternatively, the material may be directly melt-kneaded with a binder resin and then extruded and laminated onto an IJ material to obtain a charge-imparting material having a coating layer containing the material. Furthermore, these compounds may be contained in a moldable resin, and this may be molded into the shape of carrier grains f, sleeves, or doctor blades to provide a charged material.

As the binder resin or molding resin, it is best to use a commonly used binder resin or molding resin. For example, polystyrene, polyacrylic acid ester, polymethacrylic acid ester, polyacrylonitrile, rubber resins such as imprene and butadiene, polyester, polyurethane, polyamide, ebon resin, rosin, polycarbonate, phenolic resin, chlorinated paraffin, These conductors such as polyethylene, polypropylene, silicone resin, Teflon, and their combinations or mixtures thereof can be used. After coating or molding, these resins can be made to have a crosslinked structure as required to improve the durability of the surface layer of the charged material.

When using a binder resin or molding resin, the amount of the compound is 0.5 to 200 tons F per 100 beads.
It is preferable to use it in the kidney area, especially in a proportion of 2 to 100 nail parts.

When coating the surface of a charged material, it is necessary to appropriately control the amount of coating or IHT of the above compound.
A range of 0 mg/cm2 is good, preferably 0.1 mg/cm2.
cm2 to 2 mg/cm2 is good.

In addition to the above-mentioned compound 1, ceramic powder such as silica powder, aluminum chloride, cerium distillate, or silicon carbide may be used as a filler throughout the series of cases listed in L. Further, a conductive adhesive such as carbon black or tin oxide may be used to adjust the conductivity. Furthermore, in order to prevent the spent toner from accumulating on the sleeve or carrier surface, a release agent such as fatty acid gold salt, vinylidene fluoride, etc. may be used.

Known carriers can be used as the Lq material of the charged material in the carrier type, and metals such as iron, nickel, aluminum, copper, alloys, or metal compounds containing metal oxides can be used. Powder or particles P, and ceramic powder or particles such as glass, SiC, BaTi02, SrTi07, etc. are used. In addition, these surfaces may be treated with resin, etc., or resin powder,
Alternatively, resin powder containing a magnetic substance can be used. The average particle diameter is preferably about 20 to 2,504 mm.

Furthermore, the base material of the charge imparting material for the sleeve or doctor blade type yE is generally made of metals or alloys such as iron, aluminum, stainless steel, or nickel, or non-metallic compounds such as ceramics or plastics, which are generally used for the sleeve or doctor plate. +1T capacity can be used.

On the other hand, as toners to be used in combination with the above-mentioned charged material of the present invention, substantially all of those used in conventional static image development systems can be effectively used. That is, both non-magnetic and magnetic toners can be used. Than. iT L <, the toner is,
Colored fine particles containing colored n1 in a binder resin,
If necessary, magnetic powder may be included. Furthermore, these toners require less
With a charge of +7, it may contain substances such as dyes, pigments, or so-called charge control agents, as well as fluidizing agents such as colloidal silica, cerium oxide, titanium/strontium oxide, silicon carbide, etc. It may also contain lubricants such as stearinoic acid metal salts and vinylidene fluoride. Further, a conductive agent such as a carbon blank or tin oxide may be included.

As the developing method using the commercially available material and toner of the present invention described in L, substantially all of the developing methods using a two-component developer or a one-component developer can be used.

For example, magnetic brush development method, cascade development method, fur brush development method, so-called microtoning development method using magnetic substance-containing resin powder as a carrier, development method using resin powder as a carrier, so-called jumping development method, or non-magnetic development method. This is a jumping development method that develops toner.

[Example] Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 100 g of compound (1) was dissolved and dispersed in MEK 1, and an iron powder carrier (particle size: 250 to 400 me) was added to this.
sh ) IKg was dispersed and stirred in a Pall mill for about 30 minutes. After drying this iron powder carrier mixture and completely removing the solvent, light agglomerations were loosened to obtain a carrier-like charge imparting material according to the present invention.

Separately. A toner was prepared using the PX formulation without adding any charge control agent.

Styrene 100 Tunshubu (trade name: Rapen 3500, manufactured by Capo, Co., Ltd.) The materials listed in 12 were kneaded, crushed, and classified to have a particle size of 1 to 30 ILm.

This toner and the carrier were mixed at a weight ratio of IO+100 to form a developer. When the frictional electrification of this developer was measured by the blow-off method, it was -8.74 c/g. Using this developer, images were printed on a Canon 5ANP-5000 copying machine, and 50,000 sheets were printed. Even in the durability test, there was no change in image density, the m-line reproducibility was good, and the gradation was also good. There was also no force.

Example 2 100% polymethyl methacrylate resin in 1 sentence
g was dissolved, and 50 g of compound (2) was further mixed therein. This was mixed with the same iron powder carrier as in Example 1 and dried to obtain a carrier having a charge imparting effect.

When this was used in combination with a toner in the same manner as in Example 1, the BPI charge amount of the toner was -8.5 islands c/g, and when an image was produced using this, the obtained image was 50, Even in a durability test of 1,000 sheets, it showed the same good image density, fine line reproducibility, and gradation as the initial product, and there was no force fluctuation. Example 3 100% polymethyl methacrylate resin in 1 sentence
A solution was prepared in which 50 g of compound (3) was mixed with 50 g of compound (3). A developing sleeve (made of stainless steel) for Canon NP-400RE was dipped in this solution, and O. A coating of Img/cm2 to 0.8mg/c++2 was applied.

This sleeve was placed in the original developing machine.

The toner was prepared according to the following recipe using a general kneading and pulverizing method.

Styrene-butyl methacrylate 10o! lr+′
Yatsubu Yaton combination %w = 300,000 # A agent 4 Tunshubu (trade name PE-130: manufactured by Hoechst) magnetic
The particle size of the prepared toner was adjusted to ILLra to 301.

Using this toner, an image reproduction durability test was conducted using Canon's Nρ-400RE.

Durable for 50,000 sheets, there is no change in the image from the beginning, and the image is fine.
j++} The color quality and gradation were good, and there was no fog.

In addition, when the surface potential on the sleeve was determined by alII -
21V, and it was confirmed that the toner was completely negatively charged.

Example 4 A solution was prepared by dissolving 80 g of polycarbonate resin in one bottle of water and mixing with 20 g of Compound Example (4). This solution is used for Canon PC-20. ”; Developing sleeve (made of aluminum) of the developing machine for the cartridge
Di, binogu and O. on sleeve F. lmg/am'
A coating of ~0.5 mg/cm2 was applied.

This sleeve was placed in Tomo's developing machine.

On the other hand, a toner was prepared using the following recipe. Poly(styrene-butyl methacrylate 10QiQ part rate) M=15
0,000 Shape agent
4 parts by weight (trade name PE-130: manufactured by Hoechst) Blue colorant 6 parts by weight (phthalocyanine face t: 1) The prepared toner has a particle size of 1 II1 to 30ILII1.
Aligned to . Using this toner, a PC-20 was modified to enable reversal development using a developing machine equipped with the above-mentioned sleeve, and durable images were produced. As a result, there was no change in the image until the toner ran out, and a clear blue image with good m-line reproducibility and gradation was obtained. Furthermore, we measured the surface potential of the toner on the sleeve. -22V and was negatively charged.

[Effects of the Invention] 1. As described above, according to the present invention, a charge-adding agent for imparting a charge to an electrostatic charge image developing toner having a compound having a specific structure as a charge control agent on the surface thereof is provided. KE, Materials will be provided. In particular, the compound of the present invention not only has excellent load/IL controllability and stability against heating or moisture absorption, but also exists on the surface of the charged T-material by kneading and dispersing it. By doing so, a good electrically charged material with excellent durability in J9! Kushigawa with the toner can be obtained. Therefore, if this electrically charged material is used, it is possible to mix the electrically charged gamma agent only into the toner. , essential improvements can be made to various problems when improving the charging characteristics.

Claims (4)

[Claims] (1) A charge-imparting material for developing an electrostatic image, characterized in that it has a bis(diorganotincarboxylate) dicarboxylate on at least its surface. (2) The charge imparting material for developing an electrostatic image according to claim 1, which is in the form of carrier particles. (3) The charge imparting material for developing an electrostatic image according to claim 1, which is in the form of a cylindrical sleeve. (4) Claim 1 in the form of a doctor blade
A charge imparting material for developing an electrostatic image as described in 2.