JPH04177366A - Developer toner composition - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developer toner composition that can be used in an electrostatic transfer method. The present invention relates to a developer toner composition that can be fixed and can react with dyes or dye precursors to obtain sufficient color development.

[Conventional technology] Conventionally, a color developer is dispersed as ultrafine particles in an aqueous solvent, and after adjusting binders and additives, it is applied to the paper that is made into a special paper called a color developer sheet. existed as. The image forming technology using this color developer sheet is
JP-A-58-88739 and JP-A-59-3053
This method is disclosed in Japanese Patent Application Laid-Open No. 59-137944 and others. This image forming technology involves two or more components isolated from each other being released from isolation by physical external forces such as pressure or temperature changes, and reacting with each other, resulting in optical changes and absorption of light. It refers to all functions that cause changes in area or absorption intensity and are recorded in response to external forces.

For example, by overlapping a photosensitive pressure-sensitive recording medium, in which microcapsules whose mechanical breaking strength changes with light irradiation is supported on an arbitrary medium, and a color developer sheet, and performing pressure development, the mechanical breaking strength can be improved. A substance that selectively clears different microcapsules and reacts with colorless or slightly colored dyes or dye precursors contained in the microcapsules to develop a color, i.e., dye receptor or color developer. This is an image forming system that reacts with a developer to form a developed image on a developer sheet. In accordance with this image forming technology, as a means of forming an image on any recording medium, a color developer is made into powder and electrostatically flung onto any recording medium. There is a technique in which an image is formed by forming a color developer sheet, superimposing a microcapsule sheet on the color developer sheet, and performing pressure development. In addition, this pressure-fixing color developer toner, which is a color developer powder, is electrostatically adhered onto any recording medium, and then directly contacted with the microcapsule sheet and then pressurized with a pressure developing device. Therefore, it also has the ability to be pressure-fixed onto any recording medium, and contains a pressure-fixable component in the pressure-fixable color developer toner.

[Problems to be Solved by the Invention] However, when the developer is used as a powder, there is a problem that the developer toner becomes sticky due to the inherent characteristics of the developer. This is because the color developer itself is sticky, and if the conventional toner manufacturing method by pulverization is used alone, it may stick to the device, and the pressure fixing performance of the color developer toner powder may be affected. The performance was insufficient, the developing performance and fixing performance were unstable with repeated use, the toner adhered to the toner carrier and the toner case, agglomerated and caked during storage, and the storage stability was poor. Furthermore, it could also become a cause of poor charging properties. If an attempt is made to improve the flow performance, the following problems arise.

For example, a color developer with good fluidity may have poor coloring performance, or although it has fluidity, it has a high melting point, so kneading, which is one of the steps in the toner manufacturing process, cannot be performed without mixing a resin with a low melting point or a color developer. In some cases, the yield was poor due to a large amount of fine powder generated during pulverization, which is one of the toner manufacturing processes, and there were problems in weather resistance.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to obtain sufficient fixing properties by pressurization on any recording medium that is a recording medium, and to ensure fluidity as a toner. It is an object of the present invention to provide a color developer toner composition which can be used in combination with dyes and dye precursors and has good color development performance with dyes and dye precursors.

[Means for Solving the Problems] In order to achieve this object, the developer toner of the present invention has the following features:
A color developer, which is a dye receptor that develops color by reacting with a dye or a dye precursor, is composed of a polyvalent metal salt of an aromatic carboxylic acid and a phenol novolac.

[Function] According to the present invention having the above configuration, an aromatic carboxylic acid and a phenol novolac are contained as a color developer which is a dye receptor (for example, a phenol novolac 10
30 to 90 wt% of aromatic carboxylic acid is dispersed in ~60 wt% (weight percent). By mixing two types of substances that have color developing ability, you can obtain color developing ability that complements each other's color developing effect, so black density is deep, yellow,
Each single color of magenta and cyan can also produce colors with high brightness and saturation. Furthermore, it is possible to melt and knead the color developer toner at a low temperature in manufacturing the toner.

In addition, a soft substance such as an adhesive or wax is heated and mixed with these two types of developer components in order to impart pressure fixing properties to the recording medium. By crushing and classifying a mass in which the color developer component and the pressure fixing component are combined, a color developer toner having the characteristics of a toner is produced.

[Example] Hereinafter, components of an example embodying the present invention will be described.

In the image forming system in which the developer toner of this example is used, the photocurable microcapsules containing the dye and dye precursor that react with the developer are
The amount of curing changes depending on the amount of light irradiation, and the mechanical breaking strength changes depending on the amount of curing of the included photocurable resin. The microcapsules contain a dye and a dye precursor, which are color-forming media that develop color by reaction with a developer, which is a dye receptor. Examples include crystal violet lactone, 3-3-bis(p-dimethylaminophenyl)-phthalide, 3-(p-dimethylaminophenyl)
-3-(2-methylindol-3-yl)-6-dimethylaminophthalide, triallylmethane phthalide, methylene blue benzoyl, anizoyl,
Acyl derivatives such as pivaloyl: 3-diethylamino-
7-chlorofluorane, 3-diethylamino-7-dibenzylaminofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 3-methyl-cyclohexylamino-6-methyl-7-anilinofluoran Oran,
Leuco dyes such as xanthine phthalide series such as 3-ethyl-p-tolylamino-6-methyl-7-anilinofluorane are available and have been put to practical use.

On the other hand, when the dye precursor contained in the microcapsules is crushed by pressure and discharged from the microcapsules, it reacts with the developer component of the dye receiver, which is the main component of the developer toner of this example. Develops color. The color developer components include natural clay minerals such as acid clay, bentonite, and attapulgide; organic acids and their esters such as tannic acid, gallic acid, and propyl gallate; phenolic resin, maleic acid resin, and phenol-acetylene. resin,
Acidic polymers such as condensates of formaldehyde and carboxylic acids having at least one hydroxy group; zinc salicylate, silver salicylate, zinc 2-hydroxynaphthoate, zinc 3,5-di-t-butylsalicylate; 3.
Examples include metal salts of aromatic carboxylic acids such as zinc 5-di(α-methylbenzyl)salicylate; metal salt-modified phenolic resin compounds modified with polyvalent metals such as zinc and nickel.

Among these, in the present invention, a mixture of a condensate of phenol and formaldehyde in combination with a metal salt of an aromatic carboxylic acid such as salicylic acid is very effective in using a color developer as a component of a color developer toner. . Examples of condensates of phenol and formaldehyde include p-phenylphenol, p-t-butylphenol, p-octylphenol, bisphenol A, etc. and formaldehyde, and examples of metal salts of salicylic acid include 3.5
-dicyclohexylsalicylic acid, 3-cyclohexyl-
5-phenylsalicylic acid, 3-cyclohexyl-5-benzylsalicylic acid, 3-cyclohexyl-5-(α-methylbenzyl)salicylic acid, 3-(dicyclohexyl)
Salicylic acid, 3-(dicyclohexyl)-5-methylsalicylic acid, 3-(dicyclohexyl)-5-ethylsalicylic acid, 3-(synchlohexyl)-5-t-butylsalicylic acid, 3-phenyl-5-(α-methylbenzyl)
Salicylic acid, 3-phenyl-5-(α,α-dimethylbenzyl)salicylic acid, 3-(α-methylbenzyl)-5
- Cyclohexylsalicylic acid.

3.5-di(α-methylbenzyl)salicylic acid, 3-(
α-methylbenzyl)-5-(α,α-dimethylbenzyl)salicylic acid, 3-(α,α-dimethylbenzyl)-
Magnesium, aluminum, calcium, such as 5-cyclohexylsalicylic acid, 3-(α,α-dimethylbenzyl)-5-(α-methylbenzyl)salicylic acid, 3.5-di(α,α-dimethylbenzyl)salicylic acid, These include salts of manganese, iron, cobalt, nickel, copper, zinc, and tin.

When powdering a mixture of these color developers and electrostatically applying it to a desired medium, the powder characteristics of the color developer will affect the color developer's ability to form an image on the side of the recording medium. The dye adheres to the dye, causing defects in the output image and making it impossible to reliably fix it to the recording medium. Therefore, the color developer, which is a dye precursor, is given a pressure fixing ability that allows it to adhere only to the recording medium side. The pressure fixing performance of the color developer toner to the recording medium is related to the entanglement and adhesiveness of its constituent components. Fixing performance can be improved. For example, ethylene-vinyl acetate copolymer, polyvinyl ether, vinyl chloride-vinyl acetate copolymer, polyvinyl chloride, polyacrylic acid ester, ethylene-ethyl acrylate copolymer, polyvinyl acetate, which are known as adhesives, Examples include polyvinyl butyral. In addition, waxes include carnauba wax, candelilla wax, rice wax, lanolin wax, Japan wax, beeswax wax, paraffin wax, microcrystalline wax, montan acid wax, halogenated paraffin wax, amide wax, osikerite, polyethylene, Examples include polyolefins such as polypropylene.

In addition, if necessary, a white charge control agent such as a quaternary ammonium salt, an alkyl amide, an organic complex, a naphthenic acid metal salt, a fatty acid metal salt, etc. may be mixed, and a mixture of a color developer and a pressure fixing component may be mixed. It is an effective technique for the developer toner of the present invention to maintain the fluidity and charging stability of the developer toner by applying a coating to the surface as a core material or performing a spheroidization treatment.

When the manufactured color developer toner is filled into an electrostatic coating device and electrostatically transferred onto plain paper, which is a recording medium, it has good fluidity in the toner case and can be applied uniformly onto the plain paper. did it. Furthermore, the surface of the image formed on plain paper was not sticky, and an image with a black color that was indistinguishable from the black of the original could be formed.

[Experiment Example 1] Zinc 3.5-di-t-butylsalicylate... 100
Part by weight Condensate of pt-butylphenol and formaldehyde 60 parts by weight Ethylene-acrylic copolymer 30 parts by weight Polyethylene wax 20 parts by weight Lubricant
... 5 parts by weight In the above color developer toner composition, the condensate of pt-butylphenol and formaldehyde is a resin lump at the time of raw material, and zinc 3,5-di-t-butylsalicylate, polyethylene Since the wax, ethylene-acrylic copolymer, and lubricant are powders, they are mixed into powders using a Henschel mixer while dryly crushing the condensate of pt-butylphenol and formaldehyde. Next, the remaining components, mainly consisting of a condensate of pt-butylphenol and formaldehyde, are melted at 100°C by a Niegoo so that the remaining components, mainly consisting of a condensate of pt-butylphenol and formaldehyde, are coated around zinc 3,5-di-t-butylsalicylate, which has a high melting point. Knead, cool and solidify at room temperature. The developer toner composition that has been drawn out and formed into a lump is
It is ground into particles of 1.5 mm or less using a coarse grinder. This is pulverized using an air jet mill. The resulting powder is extremely fine, ranging from a few micrometers in size to hundreds of micrometers in size.
Contains even powder. Very fine powder and very coarse powder are classified and cut using an air classifier. In this way, a developer toner powder having an average particle size of about 10 μm is produced. When a developer toner using this developer composition was fixed on a recording medium by an electrostatic transfer method to develop a black color, a color with a black density of 1.86 was obtained.

[Experimental Example 2] A developer toner of around 10 μm was produced in the same manner by changing the condensate of p-t-butylphenol and formaldehyde to a condensate of p-phenylphenol and formaldehyde, and used in the electrostatic transfer method. Therefore, when the image was transferred and fixed onto a recording medium and the black density was measured, the density was 1.59. p
- A darker color can be obtained by mixing a condensate of pt-butylphenol and formaldehyde with zinc 3,5-di-t-butylsalicylate than by mixing a condensate of phenylphenol and formaldehyde.

[Experimental Example 3] Regarding 60 parts by weight of zinc 3.5-di-t-butylsalicylate for 100 parts by weight of the condensate of pt-butylphenol and formaldehyde when the composition ratio of Experimental Example 1 was reversed, A color developer toner was produced in the same manner, and the density when black was developed through electrostatic transfer and pressure development with a photosensitive and pressure sensitive recording medium was 1.65. The concentration can be reduced simply by reversing the composition ratio from Experimental Example 1. 3.5~The higher the composition ratio of zinc di-t-butylsalicylate, the higher the black density.

[Experimental Example 4] When a similar experiment was carried out by changing the condensate of p-t-butylphenol and formaldehyde in Experimental Example 3 to a condensate of p-phenylphenol and formaldehyde, the concentration when color was developed was 1.42. It became. Even in experiments with different composition ratios, the color density was inferior to that of the condensate of pt-butylphenol and formaldehyde.

The above four experimental examples are summarized in the table shown in the drawing.

[Effects of the Invention] As is clear from the detailed description above, according to the present invention, a developer toner composition that can perform good flight and transfer by an electrostatic transfer method and has sufficient black color development can be obtained. This has the advantageous effect of being industrially superior.

[Brief explanation of drawings]

The drawing is a diagram showing a table summarizing four experimental examples.

Claims (1)

[Scope of Claims] 1. A developer toner composition containing a developer which is a dye receptor that develops color by reacting with a dye or a dye precursor, and a pressure fixing component, wherein the developer is aromatic. 1. A color developer toner composition comprising a polyvalent metal salt of a group carboxylic acid and a phenol-formaldehyde resin.