JPS5882254A - Positively chargeable toner - Google Patents

Abstract

PURPOSE:To prevent fog, and to obtain a sharp image using a positively chargeable toner for color development, by adding a specified alkylaryl tin oxide as a positive charging controller to a toner binder resin by 0.5-10wt%. CONSTITUTION:Dialkyl tin oxide except dibutyl tin oxide, alkylaryl tin oxide, and diaryl tin oxide are used for a colorless positive charging controller for color developing. This is added to a binder resin, such as polystyrene by 0.5- 10wt% to obtain a positive charging binder. On the other hand, a colorant, such as rhodamine 6G lake and polystyrene or the like resin are mixed, melted, and pulverized to give a color toner. This 100pts.wt. toner and said 0.5-50pts.wt. positive charging binder are mixed to obtain a positively chargeable color toner giving sharp color.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a positively chargeable toner used for electrophotography, electrostatic recording, etc. More specifically, the present invention relates to a positively chargeable toner suitable for color development in this field.

The current method in this field is from the past.

A fine particle toner containing a charge control agent and the like.

A dry method using a powder made by mixing a carrier such as glass beads or iron powder is known. It is used in such a positively chargeable toner for dry development. Examples of positive charge control agents include fatty acid-modified nigrosine as described in Japanese Patent Publication No. 48-22) 669. However, since this charge control agent has a blackish brown color, although it can be used for black toner using carbon black as a colorant, it cannot be used for color toners such as blue, yellow, and red. Other positive charge control agents include JP-A-51-9
There are polyamine resins such as those described in Japanese Patent No. 456. Although this charge control agent is colorless and can be used for cut toners, it has the drawback of poor compatibility with resins and difficulty in dispersion.

An object of the present invention is to provide a positively chargeable toner which has all the above-mentioned drawbacks improved.

That is, the present invention relates to a positively charging toner containing a resin colorant and dibutyltin oxide, dialkyltin oxide, alkylaryltin oxide, and/or diaryltin oxide.

The present invention is characterized in that dialkyltin oxide, alkylaryltin oxide, and/or diaryltin oxide other than dibutyltin oxide is used as the positive charge control agent.

Since the control agent is colorless, it is not only particularly suitable for color toners, but also has the advantage that uniformly charged toners can be obtained because it is well dispersed in resins. It is desirable that dialkyltin oxide, pulkylaryltin oxide and/or diaryltin oxide other than dibutyltin oxide be blended in an amount of 0.5 to 10% by weight based on the resin. If it is less than 0.5% by weight, the toner will lack positive chargeability and cannot be put to practical use. Also.

If it exceeds 10% by weight, the positive chargeability of the toner is too large and the electrostatic attraction force with glass beads, iron powder, etc. used as a carrier increases.

This causes a decrease in the fluidity of the developer and a decrease in the density of one image. Specific examples of dialkyltin oxide, alkylaryltin oxide and/or cyanotin oxide other than dibutyltin oxide include:

Examples include dimethyltin oxide, dilauryltin oxide, methylphenyltin oxide, butylphenyltin oxide, and diphenyltin oxide.

As the resin used in the present invention, any conventionally known resin having a glass transition point of 40° C. or higher and 150° C. or lower, such as polystyrene resin, acrylic resin, epoxy resin, or polyester resin, can be used.

For example, polystyrene, polystyrene, poly-α
- Methylstyrene, styrene-chlorostyrene copolymer, styrene-propylene copolymer, styrene-butadiene copolymer, styrene-vinyl chloride copolymer, styrene-vinyl acetate copolymer, styrene-maleic acid copolymer,
Styrene-acrylate copolymer (styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-phenyl acrylate) copolymer), sderene-methacrylic acid ester copolymer (styrene-methyl methacrylate copolymer).

Styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-phenyl methacrylate copolymer, etc.), styrene-α-methyl chloroacrylate copolymer.

The epoxy resin used in the present invention has an epoxy equivalent of 90.
0 to 3500. Specific examples that can be particularly preferably used include 9, for example, Epicoat 1004. Epicote 1007. Epicor) 1009 Both are manufactured by Shell.

Araldai) GY60B4. Araldite GY6097
゜Araldai) GY6099, both manufactured by Ciba Geigy.

The polyester resin used in the present invention is a polycondensate consisting of a polyhydric alcohol and a polybasic acid, and preferred polyhydric alcohol components include, for example, ethylene glycol, glycerin, 1,2-propylene glycol, and 3-propylene glycol. , neopentyl glycol, IW4 butanediol, He-hexanediol, 1f4 cyclohexane dimetatool, trimethylolethane, trimethylolpropane, pentaerythritol, etc., and as polybasic acid components, for example, maleic acid, fumaric acid, acids, isophthalic acid, terephthalic acid, adipic acid, sebatimetic acid.

Trimellitic acid, pyromellitic acid, etc. can be used.

The above resins can be used alone or in combination of two or more.

The coloring agent used in the present invention may be any conventionally known pigment such as carbon black, rhodamine 6G lake, phthalocyanine blue, 7 thalocyanine green, and No1 Zyero-G.

Any conventionally known dyes such as monoazo dyes, disazo dyes, metal complex type monoazo dyes, anthraquinone dyes, phthalocyanine dyes, and triallylmethane dyes can be used.

The colorant is used in an amount of 0.1 to 50 parts by weight based on the resin,
The ratio may be determined as appropriate depending on the case. In some cases, more than 50 parts by weight may be used.

The positively chargeable toner according to the present invention may contain any conventionally known additives, such as colloidal silica, metal salts of fatty acids, fluoropolymers, and silicone oil, as required.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 96 parts by weight of (styrene/n-butyl methacrylate) copolymer, 1 part by weight of rhodamine 6G lake pigment, and 3 parts by weight of dimethyltin oxide were dry mixed and then melt-kneaded. After cooling, it was coarsely pulverized using a hammer mill, and further pulverized using an air jet type pulverizer. The obtained fine powder was classified to select particles having a particle diameter of 5 to 30 μm, which was used as a toner. 100 parts by weight of spherical iron oxide powder was mixed with 3 parts by weight of this toner to prepare a developer. The blow-off charge amount of the present agent is +40.0 (
μC/IP).

On the other hand, as a comparative toner, a toner containing no dimethyltin oxide among the above formulations was prepared, and a developer was prepared in the same manner. The blow-off charge amount of this present agent is +&2 (μC/
IP). After uniformly charging a selenium drum rotating at a circumferential speed of about 10 cm/s with a corona voltage of +5 KV, the selenium drum was irradiated with light through a negative original, and the above-mentioned 2.
Among these types, reversal development is carried out using a magnetic brush method using a developer containing dimethyltin oxide, and then the development is carried out using a magnetic brush.

One image obtained by applying a corona voltage of 15 KV from behind the plain paper was clearly clear with high image density and little capri. Similarly, when a toner not containing dimethyltin oxide was used for development, toner scattering occurred from the printing machine and only a transferred image with a low density of 9 pixels with many capri was obtained.

Example 2 In exactly the same manner as in Example 1 except that the colorant was changed to 7-talocyanine blue, toners containing dimethyltin oxide and toners not containing dimethyltin oxide were prepared, developers were prepared, and the amount of blow-off charge was measured. did. The toner containing dimethyltin oxide was +3L5 (μC/1? toner), and the toner not containing dimethyltin oxide was +0.3 (μc/iP toner). When development was carried out in the same manner as in Example 1 using both toners, 1. When using toner containing dimethyltin oxide.

A clear transferred image with clearly high image density and little capri was obtained. When a toner not containing dimethyltin oxide was used, toner scattering occurred violently from the developing machine, and the resulting transferred image had a poor image density with a large amount of capri.

Example 3 The same procedure as in Example 1 was carried out except that butylphenyltin oxide was used in place of dimethyltin oxide. The obtained developer has a blow-off charge amount of +43.5
(μC/iF), f. Using the obtained developer, reversal development was performed in the same manner as in Example 1. Result 1
The image clearly has high image density and is clear with little capri. Ivy.

Example 4 The same procedure as in Example 1 was carried out except that diphenyltin oxide was used instead of dimethyltin oxide. The obtained developer has a blow-off charge amount of +420 (μC
/lf)ner).

Further, using the obtained developer, reversal development was carried out in the same manner as in Example 1, and as a result, the nine images were clearly clear with high image density and little capri.

The present invention is characterized in that dialkyltin oxide, alkylaryltin oxide and/or diaryltin oxide other than dimethyltin oxide is used as a positive charge control agent. Because it has a positively charged axial force, the colorant does not lose its original hue.

Provides positively charged toner of desired color. Furthermore, since the above-mentioned tin oxide has good dispersibility in resin, it is possible to obtain a uniformly charged toner. Therefore, if the present invention is carried out using the toner according to the present invention, a good field with strong fogging can be obtained. It will be done.

Claims (1)

[Scope of Claims] 1. A positively chargeable toner containing a resin 9 colorant and a dialkyltin oxide, an alkylaryltin oxide, and/or a diaryltin oxide other than dibutyltin oxide. 2. The positively chargeable toner according to claim 1, wherein the content of dialkyltin oxide, alkylaryltin oxide, and/or diaryltin oxide other than dibutyltin oxide is 0.5 to 10% by weight based on the resin. .