JPS63118756A - Electrostatic charge image developing toner - Google Patents

Abstract

PURPOSE:To prevent fogging and to uniformize image quality by treating a colorant with a metal salt of carboxylic acid having a melting point of 70-250 deg.C to incorporate the metal salt in the surfaces of the colorant particles. CONSTITUTION:The colorant of the toner composed of a resin and the colorant to be used for developing an electrostatic charge image is treated with a metal salt of carboxylic acid having a melting point of 70-250 deg.C, preferably, 100-200 deg.C to incorporate the metal salt in the surfaces of the colorant particles in an amount of 0.5-20wt%, preferably, 1-15wt%. The colorant, preferably, such as carbon black, is used in an amount of 1-25wt%, preferably, 2-15wt% of the resin, thus permitting the obtained toner to be prevented from fogging or the like, uniform in image quality, improved in retentivity of copying density and the like, and high in durability even at the time of repeated uses.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an electrostatic image developing toner used for developing electrostatic latent images formed in electrophotography, electrostatic recording, etc. It is.

<Prior Art> In the development process, the developer used in electronic copying machines and the like is once attached to an image carrier such as a photoconductor on which an electrostatic image is formed, and then in the transfer process, the developer is applied to the photoconductor. After being transferred from the image to a transfer paper, it is fixed to the copy paper surface in a fixing step. At that time, the developer for developing the electrostatic charge image formed on the latent image holding surface is a two-component developer consisting of a carrier and toner, and a one-component developer (magnetic toner) that does not require a carrier. It has been known.

However, when using conventional developers, there are problems such as copy stains called fog on the fixed copy paper surface, non-uniformity in image quality, and a decrease in copy density due to continuous copying. However, there are problems with copy quality such as toner scattering, and attempts are being made to solve these problems by examining various toner raw materials and the amount of toner used.

It's still not enough.

Means to Solve the Problems> The inventors of the present invention have discovered that the problems of the conventional art can be solved and have arrived at the present invention.

That is, the gist of the present invention is to provide at least a toner for developing an electrostatic image consisting of a resin and a colorant, in which the colorant is
0-. The present invention relates to a toner for developing an electrostatic image, characterized in that the surface of colorant particles is treated with a metal salt of a carboxylic acid having a melting point of 2jO<0>C to contain the metal salt on the surface of the colorant particles.

The present invention will be explained in detail below.

Various known resin components can be used as the resin component of the toner of the present invention.

That is, examples include addition polymerization type resins such as styrene resin, styrene-acrylic resin, styrene-butadiene resin, and acrylic resin, condensation polymerization type resins such as polyester resin and polyamide resin, and epoxy resin.

Among these resins, monomers for forming addition polymerization type resins include styrene, O-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, co-, lI- dimethylstyrene,
p-n-7'tylstyrene, p-tθrt-butylstyrene, p-n-hexylstyrene, p-n-o/tylstyrene 7, p-n-nonylstyrene, p-n-decylstyrene, p-n- Dodecylstyrene, p-methoxystyrene, p-7 dinylstyrene, p-chlorostyrene, 3
．． Styrenes such as terdichlorostyrene; ethylene,
Ethylenically unsaturated monoolefins such as propylene, butylene, and imbutylene; vinyl halides such as vinyl chloride, vinylidene chloride, vinyl bromide, and vinyl fluoride;
Vinyl acetate, vinyl propionate, vinyl benzoate,
Vinyl esters such as vinyl butyrate; methyl acrylate, ethyl acrylate.

n-butyl acrylate, inbutyl acrylate.

Propyl acrylate, n-octyl acrylate.

Dodecyl acrylate, lauryl acrylate, monoethylhexyl acrylate, stearyl acrylate, λ-chloroethyl acrylate, phenyl acrylate, α-chloroacrylic tit), methyl methacrylate, ethyl methacrylate, methacrylic acid Propyl, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate.

Lauryl methacrylate, monoethylhexyl methacrylate, stearyl methacrylate.

α-methylene aliphatic monocarboxylic acid esters such as phenyl methacrylate, dimethylaminoethyl methacrylate, and diethylaminoethyl methacrylate; acrylic acid or methacrylic acid derivatives such as acrylonitrile, methacrylonitrile, and acrylamide; vinyl methyl ether, Vinyl ethers such as vinyl ethyl ether and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, and methyl isopropenyl ketone; N-vinylpyrrole, N-
N-vinyl compounds such as vinylcarbazole, N-vinylindole, and N-vinylpyrrolidone; monoolefin monomers such as vinylnaphthalene; propadiene, butadiene, isoprene, chloroprene, pentadiene,
Examples include diolefin monomers such as hexadiene. These monomers can be used alone or in combination.

In addition, monomers for forming the condensation polymerization type resin include ethylene glycol, triethylene glycol,
, coprobylene glycol, /, 3-propylene glycol, /, +1-butanediol, neopentyl glycol, /, lI-butynediol, /, lI-bis(
hydroxymethyl)cyclohexane, bisphenol A
, polyhydric alcohols such as hydrogenated bisphenol A, polyoxyethylenated bisphenol A, and polyoxypropylenated bisphenol A, polyhydric amines such as ethylenediamine, tetramethylenediamine, pentamethylenediamine, piperazine, hexamethylenediamine, and maleic acid, fumaric acid, mesaconic acid, citraconic acid,
itaconic acid, glutaconic acid, heptalacid, inphthalic acid,
Polyhydric carboxylic acids such as terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sepatic acid, malonic acid, or their acid anhydrides or esters with lower alcohols, and dimers of liluic acid can be exemplified. .

Further, as the charge control agent used as necessary in the toner of the present invention, known ones can be used. Examples include nigrosine dyes, secondary ammonium salts, polyamine resins, styrene resins containing 7 amino groups, and chromium-containing metal dyes can also be used.

The metal salt of carboxylic acid used in the present invention is a fatty acid metal salt having a linear structure, such as formic acid.

Acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, dinandoic acid, caprylic acid, pelargonic acid, lauric acid, tridecylic acid, myristic acid, bentatesylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, A of fatty acids such as behenic acid, lignoceric acid, cerotic acid, heptacanoic acid, montanic acid, melisic acid, and lafcelic acid! , Mli, Zn%Oa, Ea, P
Metal salts such as b; metal salts of unsaturated fatty acids 1 such as acrylic acid, crotonic acid, isocrotonic acid, undecylenic acid, oleic acid, elaidic acid, centreic acid, erucic acid,
A1. M, F, Zn, Oa.

Metal salts such as Ba and Pb; resin acids which are a general term for organic acids that exist in natural resins as free or esters, such as abietic acid, and A1.
Metal salts such as ME, Zn, ○a, Ba, and Pb can be used.

Various methods can be considered for treating the surface of a colorant with a metal salt of a carboxylic acid. For example, an aqueous alkaline solution of the base acid is added to an aqueous suspension of the colorant, mixed, and then the necessary treatment is performed. By adding a metal salt solution containing a metal, a desired metal salt of a carboxylic acid can be precipitated on the surface of the colorant particles. Then purified and dried.

The particle size can be adjusted by crushing.

In the present invention, the metal salt of carboxylic acid is applied to the surface of the coloring agent at about 0.0%. ! -20% by weight, preferably 13% by weight.

Further, the melting point of the metal salt of carboxylic acid is 70-230°C, preferably 100-200°C.

If the melting point is 70° C. or less, the toner tends to aggregate and fuse during continuous use, and the phenomenon of filming on the surface of the photoreceptor 1c tends to occur, which is not preferable.

In the toner of the present invention, the surface-treated colorant is preferably used in an amount of 7 to 25 parts by weight, preferably 1 to 73 parts by weight, based on 100 parts by weight of the resin.

Further, carbon black is preferred as the colorant.

In addition, additives such as a low molecular weight olefin polymer and finely powdered silica may be included as constituent components of the toner of the present invention in order to improve fixing properties and fluidity.

The toner may be produced by kneading the above-mentioned components using a kneader or the like, cooling, pulverizing and classifying. Further, the toner of the present invention can be applied not only as a two-component developer but also as a so-called one-component developer (magnetic toner) such as an encapsulated toner, a polymerized toner, and a magnetite-containing toner.

The average particle size of toner is! --〇μm is suitable.

The carrier to be mixed with the toner of the present invention to form a developer is not particularly limited, but iron powder having an average particle size of 10 to -00 μm is preferable.

Note that there is no particular restriction on the particle size of the iron powder. In this case, a so-called coated carrier coated with a fluororesin or the like can also be used for the purpose of improving durability during continuous use. Further, ferrite-based and magnetite-based iron powders can also be used.

<Examples> Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples in any way unless the gist of the invention is exceeded.

In addition, "parts" in the examples indicate "parts by weight."

Note that the melting point of the metal salt of carboxylic acid was measured by an electrothermal micromelting point measurement method.

〔Example/〕

Styrenic resin (BBM-400, Sanyo Chemical Co., Ltd.)
100 copies.

Oil black yes (manufactured by Orient Chemical Co., Ltd.)
Three parts were blended, kneaded, pulverized, and classified to obtain a black toner having an average particle size of about 1 μm. 3 parts of this toner and a fluorine thread resin coated carrier with an average particle size of 70 μm
A developer was prepared by mixing and stirring the following parts.

Next, when this developer was used in a copying machine using an organic photoconductor as a photoreceptor, copies were made at 65 degrees Celsius and 65 degrees Celsius, resulting in copies with very little capri and extremely uniform pattern areas. It was done. In addition, when we conducted a continuous copying test of 10,000 copies to examine its durability, we found that there was no image quality deterioration such as capri or flaking streaks, or toner scattering. As with copy 7, which was copied at 23° C. and a humidity of 6 degrees, a very uniform solid black copy with few capri and no transfer defects (white spots) was obtained. In addition, we conducted a continuous copying test of 10,000 copies under humid environmental conditions to examine the durability, and found that there was almost no image quality deterioration such as fogging or peeling streaks, or contamination inside the device due to toner scattering. There wasn't.

In addition, a highly uniform black area without the above-mentioned transfer defects (white spots) was obtained through a continuous copying test of io and ooo sheets.

[Example]

Styrene resin (BBM-600, Sanyo Chemical Exhibition)
lDO part oil black E5 (manufactured by Orient Chemical Co., Ltd.)
Using this recipe, a toner was prepared in the same manner as in Example, and a developer was prepared using the same carrier.
When a copying test was carried out under 90% humidity, as in Example 1, there were few transfer defects with few capri (continuous copying of extremely uniform solid areas with no white gaps/0,0
Obtained through 00 sheets. In addition, there was almost no image quality deterioration such as capri, brush lines, or contamination within the apparatus due to toner scattering.

[Example J]

A black toner and developer were prepared in exactly the same manner as in Example 1, except that carbon black was treated with 70% by weight of zinc stearate.

Next, using this developer, the temperature was set at ar°C and A as in Example.
! 1fi [and 7 parts ℃, continuous under 90% humidity / 0
．． When a copying test of 000 copies was carried out, copies with extremely uniform peta portions with few capri and no transfer defects (white spots) were obtained. In addition, there was almost no image quality deterioration such as capri or brush lines, or contamination within the apparatus due to toner scattering.

[Example Tei]

A toner was prepared in the same manner as in Example/, except that 3 parts of Bondron P-j/(manufactured by Orient Chemical Co., Ltd.) was added instead of Oil Black BS (manufactured by Orient Chemical Co., Ltd.) in Example/.
A developer was prepared.

Next, using this developer, the same procedure as in Example 1 was carried out. r℃, A! The humidity and... When a continuous copying test of 10,000 copies was carried out at J-°C and 0% humidity, very uniform solid copies with few capri and no transfer defects (white spots) were obtained. Furthermore, there was almost no deterioration in image quality or contamination within the apparatus due to toner scattering.

Oil black BS (manufactured by Orient Chemical Co., Ltd.)
3-part carbon black (MA-100, manufactured by Mitsubishi Chemical Corporation)
10 parts were converted into toner in the same manner as in Example to prepare a developer. This developer was prepared in exactly the same manner as in the example at 3°C and 6°C. Continuous copying tests were carried out under 5℃, A, t% humidity and 33℃ and 20℃ humidity. [Nuke] is noticeable about -,00
No light was emitted when using up to 0 sheets. Also, 33℃, 909&
In a continuous copying test under humidity, transfer omissions (white spots) in the peta area were significantly worsened, and contamination inside the apparatus occurred due to toner scattering, making it unusable.

[Comparative example]

A toner and a developer were prepared in the same manner as in Example D, except that carbon black not treated with zinc stearate was used. Next, when this developer was poured and a copying test was carried out in the same manner as in Example, the results were similar to those in Comparative Example, and it was not usable.

<Effects of the Invention> The electrostatic image developing toner of the present invention does not generate capri or the like even after repeated copying, provides uniform image quality, and is highly durable with improved copy density reduction. It is possible to reduce contamination of the inside of the copying machine due to toner damage and toner scattering.

Sender: Mitsubishi Chemical Industries, Ltd. Representative Patent Attorney Hase - Others/names

Claims (3)

[Claims] (1) In an electrostatic image developing toner comprising at least a resin and a colorant, the colorant is treated with a metal salt of a carboxylic acid having a melting point of 70 to 250°C, and the metal salt is coated on the surface of the colorant particles. A toner for developing an electrostatic image, characterized by containing the following. (2) The colorant contains a metal salt of carboxylic acid at 0.00% per colorant.
The toner for developing an electrostatic image according to claim 1, characterized in that the toner contains 5 to 20% by weight. (3) The toner for developing an electrostatic image according to claim 1 or 2, wherein the colorant is carbon black.