JPH02168273A - Negatively chargeable developer to be used for development of electrostatic charge image - Google Patents

Abstract

PURPOSE:To improve the quality of developed picture images by constituting a negatively chargeable developer of a carrier coated with a blended resin of a vinylidene fluoride/tetrafluoro-ethylene copolymer with a polymer contg. (meth)acrylic ester having a specified group as monomer component, and a negatively chargeable toner. CONSTITUTION:The developer consists of a carrier coated with a blended resin consisting of a vinylidene fluoride/tetrafluoro-ethylene copolymer and a polymer contg. (meth)acrylic ester expressed by the formula I or II, having a side chain substituted with F atoms, and a polyester type color toner contg. a colorant. Preferred molar copolymn,. ratio of the vinylidene fluoride/tetrafluoro ethylene copolymer to be contained in the cover layer of the carrier is 70:30-95:5, more pref. 75:25-95:5. In the formulas, each R<1> and R<2> is an H atom or a methyl group; each n and p is an integer 1-8; each m and q is an integer 1-19. Thus, picture images having high picture quality are obtd. for over a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a developer used for developing electrostatic latent images in electrophotography and electrostatic recording.

More specifically, a negatively chargeable small-sized developing carrier consisting of a core material and a coating resin layer, which is excellent in chargeability, surface stain resistance, mechanical strength, adhesion between the core and the coating layer, etc., and a toner. This invention relates to a particle size color developer.

[Prior art] Conventionally, as an electrophotographic method, US Patent No. 2,297°69
Specification No. 1, Japanese Patent Publication No. 42-23910 (U.S. Pat. No. 3,688,383), Japanese Patent Publication No. 43-247
4s Publication (U.S. Pat. No. 4,071,361)
Many methods are known, such as, but in general, an electrical latent image is formed on a photoreceptor by various means using a photoconductive substance, and then the latent image is transferred to developer powder (hereinafter referred to as toner). ), and after transferring the toner image to a transfer material such as paper as necessary, it is fixed by heat, pressure, a pressurized heat constant roller, solvent vapor, etc. to obtain a copy. In addition, if there is a step of transferring a toner image, usually
A step is provided to remove residual toner on the photoreceptor.

In recent years, there has been a rapid shift from monochrome copying to full-color copying in copying machines and the like.

Consideration and practical application of two-color and full-color copying machines have also been made extensively.
ol 22. No. 1 (1i383) and “Journal of Electrophotography Society J Vol 25. No. I P52 (19
There are also reports on color reproducibility and gradation reproducibility as shown in 8B).

However, unlike television, photographs, and color printed matter, there is no immediate comparison with the real thing, and for people who are used to seeing color images that are more beautiful than the real thing, full-color electronic photographs, which are currently in practical use, are The images are not necessarily satisfactory.

Color image formation by full-color electrophotography generally requires 3
All colors are reproduced using toner of three primary colors: yellow, magenta, and cyan.

The method involves first passing light from the original through a color-separating light transmitting filter that has a complementary color to the toner color to form an electrostatic latent image on the photoconductive layer.Then, through a development and transfer process, the toner is transferred to the support. The toners are held and then the above-mentioned steps are sequentially repeated several times, and the toners are superimposed on the same support while registering, and a final full-color image is obtained by one fixation.

The developing method used at this time is US Pat.
Cascade development method described in No. 8,552, U.S. Pat.
There are the magnetic brush method described in No. 874.0113, and other touchdown methods.

Among these, the most commonly used method is the magnetic brush method.

In this method, a developer consisting of toner, a magnetic carrier, and a rear is held by a magnet, and the magnetic field of the magnet causes the developer to be arranged in a brush-like manner. When this magnetic brush contacts the electrostatic latent image surface on the photoconductive layer, only toner is attracted from the brush to the electrostatic latent image to effect development.

In general, in the case of a so-called two-component development system in which the developer consists of toner and carrier, the developer charges the toner to the required charge amount and charge polarity by friction with the carrier, and uses electrostatic attraction. It is used to develop electrostatic images. Therefore, in order to obtain a good visible image, it is necessary that the toner has good triboelectric chargeability, which is determined mainly by the relationship with the carrier.

Carriers are broadly classified into coated carriers and non-coated carriers, but the former is less popular when considering developer life, etc., and various types of coated carriers have been developed and put into practical use today. .

A typical coated carrier is a carrier in which a carrier core material made of a ferromagnetic material such as iron, nickel, or ferrite is uniformly coated with an insulating resin. The toner particles are less likely to fuse to the surface of the carrier than in the case of a conductive carrier, and at the same time, the frictional electrification between the toner and the carrier can be controlled, resulting in relatively excellent durability. Another advantage is that it can be used in high-speed electronic copying machines. However, in this insulating carrier, it is necessary that the coating layer covering the surface of the carrier core material has sufficient abrasion resistance (durability) and that the coating layer is good enough to prevent toner from forming a film on the carrier surface. It is required to have anti-sticking properties and to be able to obtain a charged state of a desired magnitude and polarity by friction with a specific toner used together with a carrier (charging property).

That is, the insulating carrier is rubbed against other carrier particles, toner particles, and the wall of the device in the developing device, but when the coating layer is worn away by this friction, the stability of the charging characteristics caused by the friction with the toner is lost. In the end, it is necessary to impart the desired charge state yE to the toner particles.Furthermore, the layer of the insulating carrier has sufficient resistance to JJI!
Even if it has abrasive properties, if its adhesion to the core material is poor, the coating layer will separate or crumble due to the above-mentioned friction, resulting in a similar loss of charging properties. Furthermore, if toner adheres to the surface of the coating layer and a coating is formed, the charging characteristics will become unstable. In either case, it becomes necessary to quickly replace the entire developer with a new one.

Conventionally, as a method to improve such drawbacks, a technique of coating the surface of the carrier core material with a blended polymer (Japanese Patent Application Laid-Open No.
4-110839) and carriers in which the surface of the core material is coated with a vinylidene fluoride/tetrafluoroethylene copolymer or a blend of these copolymers and a second polymer are known. (Unexamined Japanese Patent Publication No. 58-208754, 8O
-17Ei048, 80-176049, 60
~No. 176050, No. 60-176051, No. 60-
No. 176052, No. H-178053, No. 80-17
8054 and 80-178055).

Also known is a carrier that uses acrylate having a fluorine atom in its side chain as a coating resin;
No. 0181, No. 82-80669, No. 62-2735
No. 75, No. 82-273578, No. 82-27357
This type of carrier has also been reported in publications such as No. 7 and No. 62273578.

However, in the case of carriers coated with vinylidene fluoride/tetrafluoroethylene copolymer, the resin is soft and the coating layer wears out, resulting in lack of durability and poor adhesion to the core. However, in the case of carriers coated with a polymer blend of vinylidene fluoride/tetrafluoroethylene copolymer and a second polymer, the blend of the second polymer does indeed reduce adhesion to the core. Although the resin itself has become harder and the durability has improved, the carrier has poor compatibility with the vinylidene fluoride/tetrafluoroethylene copolymer and is not satisfactory in terms of stable charging performance. This has not yet been achieved.

Furthermore, in the case of a carrier coated with a resin containing an acrylic polymer containing fluorine atoms, although adhesion to the core and durability are satisfactory, the charging strength is generally excessive and stable image density cannot be obtained. The drawback was that it disappeared.

Furthermore, in recent years, there has been an increasing demand in the market for high definition and high image quality in copying machines, and attempts have been made in this technical field to achieve high quality color images by reducing the particle size of toner. As the diameter becomes smaller, the surface thickness per unit weight increases, and the n? The amount of electricity tends to increase1
There are concerns about low image density and deterioration of durability.

In addition, since the amount of charge on the toner is large, the adhesion between the toners is strong and the fluidity is reduced, causing problems in the stability of toner replenishment and in the application of tripo to the replenishment toner.

Furthermore, in the case of color toner, since it does not contain a magnetic material or a conductive substance such as carbon black, there is no part that leaks charge, and the amount of charge generally tends to be large.

In addition, especially for color toners, the following properties are strongly desired. It is necessary that the melting state is so close to complete that it is impossible to tell.

(CI) It must be a colored toner with transparency that does not interfere with toner layers of different tones below the toner layer.

(c) Each of the constituent toners must have well-balanced hue and spectral reflection characteristics, and sufficient saturation.

Although many studies have been made regarding binder resins, no toner has yet been developed that satisfies all of the above characteristics.

Today, polyester-based resins are often used as color binder resins in this technical field, but toners made of polyester resins are generally easily affected by temperature and humidity, and the band's 1. Problems such as excessive amount of toner and insufficient amount of charge under high humidity occur, and there is an urgent need to develop color toners that have a stable amount of charge in a wide range of environments.

For the reasons mentioned above, there are high expectations for carriers that mainly control the triboelectrification properties of toner.
There is a strong desire to develop a color developer comprising a carrier that simultaneously satisfies impact resistance, abrasion resistance, good adhesion to the core, etc.

[Problems to be Solved by the Invention] An object of the present invention is to provide a negatively chargeable color developer for electrostatic charge development that solves the above-mentioned problems.

In other words, the purpose of this research is to
<An object of the present invention is to provide a negatively chargeable color developer for electrostatic charge development which always has stable triboelectric chargeability.

A further purpose of this research is to provide a negatively chargeable color developer for electrostatic charge development that has clear image characteristics without fog and has excellent durability and stability.

The further objectives of this research are to achieve high image density, excellent color mixing,
It is an object of the present invention to provide a negatively chargeable color developer for electrostatic charge development which has excellent transparency especially in OHP.

[Means and effects for solving the problems] The electrostatic developer according to the present invention that can achieve the object and purpose is a polyvinylisofluoride/
/Contains a tetrafluoroethylene copolymer and an acrylic acid or methacrylic acid ester having a group formed by substituting a fluorine atom in the side chain as shown in the general formula (1) or (2) below as a monomer component. A carrier coated with a blend resin with a polymer of general formula (1) and general formula (2) [where R1
, R2 each represent a hydrogen atom or a methyl group, and n
, p each represents an integer of 1 to 8, and 1m + q each represents an integer of 1 to 19.] A colorant-containing polyester color toner.

At least one monomer selected from acrylic acid (or ester thereof) monomer and methacrylic acid (or ester thereof) monomer and at least one monomer selected from styrene monomer are polymerized. A carrier coated with a resin containing a copolymer obtained by the above method has excellent adhesion between the core and the resin, and can provide a stable coated carrier. There is a tendency to give an amount of charge of . Therefore, it is possible to suppress the amount of charge on the toner by coating the toner with a polymer blend of a fluorine-containing resin that is charged with the opposite polarity to the above copolymer, but the compatibility between the fluorine-containing resin and the above copolymer is Unfortunately, good film properties have not been obtained, and issues still need to be resolved in terms of adhesion between the surface layer of the carrier core material and the coating resin, as well as dispersibility and compatibility when blending with the second polymer. There are many players, and even today, a satisfactory court career is still not available.

The carrier of the present invention is characterized by containing vinylidene fluoride/tetrafluoroethylene copolymer and an acrylic ester or methacrylic ester having a group substituted with a fluorine atom in the side chain as monomer components. The acrylic part of the fluorine-containing acrylic ester improves adhesion to the core, and the fluorine-substituted part at the end improves dispersibility and compatibility with negative resins. It is designed with separate functions.

In addition, in the present invention, the combination b1 of the fluorine-containing acrylic ester component of the fluorine-containing acrylic ester combination
Furthermore, the charging characteristics of the carrier can be changed by controlling the one-female prime number of the linear alkyl chain of the fluorine-containing acrylic ester and by changing the degree of fluorine atom substitution.

For example, negative SE1? By increasing the fluorine-containing acrylic ester component having electrical properties, the carrier becomes more likely to be negatively charged, and the amount of charge of the toner is controlled relative to the negatively charged toner during frictional charging.

In addition, as the number of carbon atoms in the alkyl straight chain increases, the fluorine-substituted moiety of the fluorine-containing acrylic ester is more likely to appear on the carrier surface layer, and as a result, the resistant fluororesin is more likely to be uniformly dispersed on the carrier surface. , suppresses excessive charging of negatively charged toner. Also, if the degree of fluorine atom substitution in the fluorine-containing acrylic ester increases, will it affect the carrier? i? The electric properties shift to negative chargeability, which is effective in suppressing excessive toner charging.

” - The carrier of the present invention has been designed and developed with separate functions in terms of polymer coating properties on the carrier core material, uniform dispersion of negative resin, and charging characteristics, and has excellent durability. This makes it possible to provide a carrier with excellent and stable charging characteristics.

The copolymerization molar ratio of the polyvinylidene chloride/tetrafluoroethylene copolymer contained in the coating layer of the carrier of the present invention is 70
:30-95:5 range is preferable, more preferably 7
The range is from 5:25 to 90:10. When the molar composition ratio of the copolymer is within the above range, the solvent solubility will be improved, and the film formability and the tensile strength will be improved, thereby ultimately improving the durability.

The acrylic ester having a group substituted with a fluorine atom in the side chain contained in the carrier coating layer of the present invention is preferably composed of a monomer represented by the following general formula (1) or (2). .

General formula (1) General formula (2) LILI(
1;R2JnL;a? 2m, l L; LJ
U(L;H2]p(I+2)qtll In the two formulas, R1,
R2 each represents a hydrogen atom or a methyl group, and nr
P each represents an integer from 1 to 8, and m and q each represent an integer from 1 to 19.

Specific examples of acrylic esters having fluorine atoms substituted in the side chains used in the present invention include acrylic acid (methacrylic acid)-1,1 dihydroperfluoroethyl, acrylic acid (methacrylic acid)-1,1 dihydroperfluoroethyl, acrylic acid (methacrylic acid) )-1,1
-dihydroperfluoro-n-propyl, acrylic acid (
Methacrylic q)-1,1,3-trihydroperfluoro-n-propyl, acrylic acid (methacrylic acid)-1,1
, 5-) dihydroperfluoro-n-butyl, acrylic acid (methacrylic acid)-1,1,5-trihydroperfluoro-n-amyl, and the like.

In the present invention, the ff1INL component used in the polymer contained in the coating layer together with the vinylidene fluoride/tetrafluoroethylene copolymer (hereinafter referred to as the polymer used in the present invention) has fluorine atoms substituted in the side chains. The acrylic ester having the group formed by the above may be used alone, but it may also contain other components, such as acrylic (methacrylic) acid, methyl acrylic (methacrylate) acid, Acrylic (methacrylic) m-ethyl, butyl acrylic (methacrylic) acid, benzyl acrylic (methacrylic) acid, acrylic (methacrylic) acid amide, cyclohexyl acrylic (methacrylic) acid, glycidyl acrylic (methacrylic) acid, hydroxyethyl acrylic (methacrylic) acid, Styrene, vinyl acetate, ethylene, propylene, isoprene, etc. can be mentioned.

Specific examples of the polymer used in the present invention include, but are not limited to, the following.

[Exemplary Compounds] Polymer (1) Polymer (2) UUUH?
T;? 2 UULJUH2Ul' 2 Sil' Tripolymer (5) COOCR2(CF3)2B COOCH2(CF2)40F3 CQOCH2(CF2)+oCF3 Polymer (12) Polymer (24) The polymer blend ratio in the present invention is vinylidene fluoride/ A polyethylene tetrafluoride copolymer containing 20 to 80% by weight, preferably 30 to 70% by weight, and containing as a monomer component an acrylic ester having a group formed by substituting a fluorine atom in a side chain. The amount of coalescence is 80-20% by weight, preferably 70-30% by weight.

If the polymer blend ratio of negative resin is more than 80%, the compatibility of the resin is poor, and if it is less than 20%, it has excellent film properties and abrasion resistance, but is not effective in suppressing excessive charge amount. Does not perform well.

The coating layer of the carrier of the present invention contains a polymer made of the above-mentioned polymer blend, but it is also possible to contain a third component system if necessary.

As the carrier core material used in the present invention, for example, surface oxidized or unoxidized metals such as iron, nickel, copper, lead, cobalt, manganese, chromium, rare earths, alloys or oxides thereof, and ferrite are used. can. A particularly preferable form is Cu-Zn-Fe ternary ferrite, and the manufacturing method thereof is not particularly restricted.

The average particle size of these carriers is preferably 20 to 70 g, more preferably 25 to 70 g, more preferably 30 to 85 g.

The carrier particles of the present invention are produced by surface-treating the core material as described above with the polymer (including copolymer) of the present invention as described above, and then chemically bonding or adsorbing the core material to the surface of the core material. It can be obtained by forming a coating layer of a copolymer.

For surface treatment of the core material 1, the carrier core material is immersed in a solution obtained, for example, by dissolving the above-mentioned polymers, copolymers or mixtures of other resin materials in a suitable solvent, and then A method of removing solvent, drying, and high-temperature baking, or a method of suspending the core material in a fluidized bed, spraying the polymer solution, drying, and high-temperature baking can be used, but the manufacturing method is There are no particular restrictions.

The treatment of the above compound may be appropriately determined so that the carrier satisfies the above conditions, but generally the total amount is 0.1 to 5% by weight (preferably 0.3 to 3% by weight) based on the carrier of the present invention.
Intussusception%) is desirable.

When preparing a two-component developer by mixing with the color toner according to the present invention, the mixing ratio is 2.0% to 12% by weight, preferably 3% to 12% by weight, in terms of toner concentration in the developer.
Good results are usually obtained at 9% by weight. Toner density is 5. (If it is less than 1%, the image density will be too low to be practical; if it is more than 15%, it will increase fogging and in-machine scattering, and shorten the useful life of the developer.

As the toner term MsI resin used in the present invention, various resin materials conventionally known as toner binder resins for electrophotography are used.

For example, polystyrene, styrene-butadiene coelectrolyte, styrene-based copolymers such as styrene-acrylic copolymer, polyethylene, ethylene-vinyl acetate Jt' ffi
These include ethylene copolymers such as ethylene and vinyl alcohol copolymers, phenol resins, epoxy resins, acryl phthalate resins, polyamide resins, polyester resins, maleic acid resins, etc. Furthermore, there are no particular restrictions on the manufacturing method of any of the resins.

Among these resins, polyester resin is suitable for undeveloped moons. Although polyester resin has excellent fixing properties and is suitable for color toners, it has a strong negative (17) charge and tends to be overly charged.Therefore, when polyester resin is used in the present invention, the disadvantages can be improved and an excellent toner can be produced. can get.

In particular, the following formula (where R is an ethylene or propylene group, !,!
are each an integer greater than or equal to l, and! The Mo-yen Ibi 1 of Ten Te is 2-10. ) or bisphenol 1 derivative represented by 'j! i conversion as the diol component, 2
A carboxylic acid component (for example, fumaric acid, maleic acid, maleic anhydride, phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, etc.) consisting of a carboxylic acid, its anhydride, or its lower alkyl ester having a higher molecular weight than the Polyester resins subjected to cocondensation polymerization are preferred.

In particular, in terms of permeability in trapene, the apparent viscosity at 90°C is 5 x 104 to 5 x 106 poise, preferably 7.5 x 104 to 2 x 106 poise, more preferably 105 to 106 poise, and at 100°C. The apparent viscosity at is 104-5 x 105 voids, preferably 104-3. OX105 boiz, more preferably 10
By having a void of 4 to 2 x 105, a color 〇) IP with good transparency can be obtained, and even as a full color toner, good results can be obtained in fixing properties, color mixing properties, and high temperature offset resistance.

In particular, the absolute value of the difference between the apparent viscosity PI at 90°C and the apparent viscosity P2 at 100°C is 2 x 105 < IP
It is preferable that I-P21<4×106.

When the above resins are used to make fine particles, most of them exhibit negative 4if charge even without the use of a charge control agent.
Although it can be used as is for ungenerated IJ, it is preferable to use a charge control agent that imparts negative chargeability.

As the charge control agent used in "Unreleased 1", a conventionally known negative charge control agent may be used.

For example, organic salts or complexes containing a metal with a valence of 2 or more are exemplified. Effective metal species include AI, Ba,
Ca, Cd, Go, Cr, Cu, Fe,
Hg, Mg, Mn.

Examples include polyvalent materials such as Ni, Pb, Sn, Sr, and Zn. As the organometallic compound, carboxylates, alkoxylates, organometallic complexes, and chelate compounds of the above metals are effective, and examples include zinc acetate.

Magnesium acetate, calcium acetate, aluminum acetate, magnesium stearate, calcium stearate, aluminum stearate, aluminum isopropoxide, aluminum acetylacetonate, iron(II)
) acetylacetonate, chromium 3,5-di-tert-butylsalicylate, etc., and acetylacetone metal complexes and salicyl ugly metal salts are particularly preferred.

In the present invention, particularly light-colored salicylic acid-based chromium salts,
When a charge control agent, preferably a zinc salt or an aluminum salt, is added to the toner, it is added in an amount of 0.1 to 18 parts by weight, preferably 0.5 to 8 parts by weight, per 100 parts by weight of the binder resin. good.

All known colorants can be used in the toner of the present invention, such as carbon black, iron black, nigrosine, benzidine yellow, quinacridone, rhodamine B, and phthalocyanine blue.

If necessary, additives may be mixed into the toner of the present invention within a range that does not impair the properties of the toner. Examples of such additives include lubricants such as Teflon, zinc stearate, and polyvinylidene fluoride; Alternatively, there is a fixing aid (for example, low molecular weight h1 polyethylene, low molecular weight abrasive polypropylene, etc.)':J.

In producing the toner of the present invention, the constituent materials are thoroughly kneaded using a heat kneader such as a hot roll, a niegu, or an extruder, and then mechanically crushed and classified.
Alternatively, a method of dispersing a material such as a coloring agent in a binder resin solution and then spray-drying it;
Various methods can be applied, such as a polymerized toner production method in which a toner is obtained by mixing a specified material into a riiM body to form an MIi resin and then polymerizing the emulsified suspension.

The particle size of the coloring agent-containing fine particles used for the undeveloped material 11 is preferably 4 to 100% in volumetric average diameter, 16.0 or more in layer thickness, and 1.0% or less of coarse particles in pot distribution.

In addition, in the case of spherical toner such as polymerized toner, the body M=F
It is preferable that the average diameter is 3 to I (lμ).

Since the toner used in the present invention has a fine particle size, the toner adheres faithfully to a minute electrostatic latent image, and there is little disturbance in the toner adhesion at the end of the electrostatic latent image.

As a result, an image with high resolution and good color reproducibility can be obtained. In particular, in photographic images, there are many halftone areas that are collections of minute latent images, and the effect of one grain size is even more apparent, resulting in a good image.

The fluidity improver used in the present invention is one that can increase fluidity when added to the colorant-containing resin particles when comparing before and after addition.

Anything can be used.

For example, fluororesin powder, such as vinylidene fluoride fine powder, polytetrafluoroethylene powder, etc.; or fatty acid metal salts, such as zinc stearate, calcium stearate, lead stearate, etc.; or metal oxides,
That is, zinc oxide powder, etc.; or finely powdered silica, that is, wet-processed silica, dry-processed silica, and treated silica in which these silicas are surface-treated with a silane coupling agent, a titanium coupling agent, silicone oil, etc.

The amount added to the colorant-containing resin particles is 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, per 100 parts by weight of the mononuclear resin particles. If it is less than 0.01 part by weight, it will not be effective in improving fluidity, and if it is more than 10 parts by weight, it will promote fogging, smearing of letters, and scattering inside the machine.

Further, the toner of the present invention may be one in which the fluidity imparting agent as described above is fixed and embedded on the surface of the toner by mechanical impact.

Here, a method for measuring the chargeability and amount of charge in the unexploded 151 will be described in detail using the drawings.

FIG. 1 is an explanatory diagram of a friction zone one-blade measuring device.

First, a mixture of particles whose Δ1 is to be determined and magnetic particles used as a developer is prepared. In the case of toner and colorant-containing fine particles, the mixing ratio is 1 part by weight to 2 parts by weight of 9 parts of magnetic particles, and in the case of a fluidity imparting agent, 2 parts by weight to 98 parts by weight of magnetic particles. Parts by weight.

Particles to be measured and magnetic particles 2F are placed in a measurement environment and left for 12 hours or more, then placed in a polyethylene bottle, mixed and stirred for a few minutes.

Next, a mixture of the particles whose triboelectric charge is to be measured and the magnetic particles is placed on a metal measuring 8 base 2 with a conductive screen 3 of 500 mesh (ITrfi appropriately changed to a size that does not allow Gi magnetic particles to pass through) at the bottom. Pour in and cover with metal lid 4. At this time, the weight j, l of the entire measurement container 2 is calculated as -1 (g
) Next, in the suction device 1 (at least the part in contact with the measurement volume 2 is an insulator), suction is carried out from the suction lower, and the air volume control valve 6 is adjusted to set the pressure of the vacuum gauge 5 to 250 mmAq. In this state, suction is performed sufficiently (for about 2 minutes) to remove the toner. The potential of the electrometer 9 at this time is V (volts), where 8 is a capacitor whose capacity is C(
μF), and weigh the weight of the entire measuring container after suction and let it be lh (g). This triboelectric charge amount T (ripple c/g) is calculated as shown in the following formula.

Next, a method for measuring the particle size distribution of unexploded 1311 will be explained.

The measuring device is a Coulter counter TA-II type (
(manufactured by Coulter) and an interface (manufactured by Nikkaki) that outputs the number average distribution 9 volume average distribution and CX~1
A personal computer (Cannon Acid) is connected, and a 1% NaCR aqueous solution is prepared using primary sodium chloride as the electrolyte.

As a measuring method, a surfactant as a dispersant, preferably alkylbenzenesulfonic acid n1, is added at 0.1 to 5 mA+ to 100 to 150 mj' of the electrolytic aqueous solution, and 0.5 to 505 g of a measurement sample is added.

The electrolytic solution in which the sample was suspended was dispersed using an ultrasonic disperser for about 1 to 3 minutes, and then the Coulter Counter TA-II was used to obtain particles with a particle size of 2 to 40 μm using a 100-layer aperture as an aperture. The distribution is measured to determine the volume average portion h and the number average distribution.

From the volume average distribution and number average distribution obtained, 20.2 of the average grain size of the potted plant and the average grain size of the 8 bodies are calculated as 11.

[Example] Examples of unexploded 1g1 will be described in detail below. still"%"
"1 part" indicates the amount of 1 part by weight.

Toner Production Example 1 was sufficiently premixed using a Hennel mixer, melt-kneaded at least twice using a three-roll mill, and after cooling, coarsely ground to about 1-21 using a hammer mill, and then by an air jet method. It was pulverized using a pulverizer. Further, the obtained finely ground product was classified and a particle size distribution of 2 to 10 pm was selected so as to have the particle size distribution of the present invention to obtain colorant-containing resin particles with a volume average particle size of 78.

This apparent viscosity is 6t at 90°C, 0XI05 voids.

1 at 100°C. It was IX104 Boyz.

0.6 parts of colloidal silica is added to 100 parts of the above colorant-containing resin particles (primary particle size 0.1 to 0 as determined by microscopy observation).
．． 2) was added externally to prepare a cyan toner.

Toner Production Example 2 173.5 parts of CI Pigment Yellow was used in place of Phthalocyanine 4 to make a 7.6 liter yellow toner.

Toner Production Example 3 Instead of the phthalocyanine pigment, 0.9 parts of Cl Solvent Red 49 and 1 part of Cl Solvent Red 52 were used.
, (1?B was used to make a 7.5p magenta toner.

Toner Production Example 4 Instead of the phthalocyanine pigment, use CI Pigment Yellow 17 at 1.2 f! II, 2.8 parts of CI Pigment Red 5 and 1.5 parts of CI Pigment Blue 15 were used to prepare a 7.5μ black toner.

Carrier production example 1 Vinylidene fluoride and tetrafluoroethylene in a molar ratio of 80:
A polymer blend of the vinylidene fluoride/tetrafluoroethylene copolymer obtained by the reaction in step 20 and exemplified polymer (1) at a weight ratio of 50:50 was used for weight average diameter 52, 3SpQ, and 3. A Cu-ZnFe-based ferrite carrier having a particle size distribution of 5%, 35-40μ8%, and 74 or more and 0.5% was coated with 1% by weight to obtain carrier 1.

Carrier Production Example 2 Carrier 2 was produced in the same manner as in Production Example 1 except that Exemplified Polymer (2) was used as the fluorine-containing methacrylic acid ester polymer instead of Exemplified Polymer (1) in Carrier Production Example 1. And so.

Carrier Production Example 3 Carrier 3 was prepared in the same manner as in Carrier Production Example 1 except that vinylidene fluoride and tetrafluoroethylene were reacted in a molar ratio of 90:10.

Carrier Production Example 4 Carrier Production Example 1 except that exemplified polymer (18) was used instead of exemplified polymer (1) and the ratio of negative resin and exemplified polymer (18) was 70:30. A carrier 4 was prepared in the same manner as in Production Example 1.

Carrier Production Example 5 Carrier Production 41 #1 except that Exemplified Polymer (3), which is a copolymer of a fluorine-containing methacrylic ester and a methacrylic ester, was used instead of Exemplified Polymer (1). Carrier 5 was prepared in the same manner as in Example 1.

Carrier production example 6 Vinylidene fluoride and tetrafluoroethylene in a molar ratio of 80
: Produced in the same manner as in Production Example 1, except that only the vinylidene fluoride/tetrafluoroethylene copolymer obtained by the reaction in step 20 was used and the fluorine-containing acrylic acid ester polymer was not blended. I got Comparison Carrier 1.

Carrier Production Example 7 Comparative Carrier 2 was obtained by using only Exemplified Polymer (1) and using Carrier 1 except that it was not blended with negative resin.

Carrier Production Example 8 Comparative Carrier 3 #11 was prepared in the same manner as Carrier I except that methyl methacrylate copolymer was used instead of Exemplary Polymer (1) in Carrier Production Example 1.

Carrier Production Example 9 Comparative carrier 4 was obtained in the same manner as Production Example 1, except that Ml to be coated with resin was 6% by weight.

Production Example 10 of Carrier Production Example 1 except that in Production Example 1, the negative resin and the exemplary polymer (1) were used at a blend ratio of 10+90.
I got a comparison carrier 5 after doing this.

Production Example 11 of Carrier Production Example 1 except that the molar ratio of vinylidene fluoride and tetrafluoroethylene was changed to 50:50 in Production Example 1.
Comparison carrier 6 was obtained in the same manner as above.

Table 1 shows the results of imaging with CLC-1 (cannon acid) using each carrier shown in Carrier Production Examples 1-11.The toners were the four-color toners shown in Toner Production Examples 1-4. A full-color image was obtained using

(Hereinafter in the margin) [Effects of the Invention] As described above, when the developer of the present invention is used, high-quality images can be obtained over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a triboelectric charge measuring device used in the present invention.

Claims (5)

[Claims] (1) Coating with a blend resin of vinylidene fluoride/ethylene tetrafluoride copolymer and a polymer containing as a monomer component acrylic acid or methacrylic acid ester having a group formed by substituting a fluorine atom on the side chain A negatively chargeable developer for electrostatic charge development comprising a carrier and a negatively chargeable toner. (2) The electrostatic charge developing device according to claim 1, wherein the acrylic acid or methacrylic ester having a group formed by substituting a fluorine atom in a side chain is represented by the following general formula (1) or (2). Negatively charging developer. General formula (1) General formula (2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R^1 and R^2 each represent a hydrogen atom or a methyl group. , n and p each represent an integer of 1 to 8, and m and q each represent an integer of 1 to 19. ] (3) A polymer containing 20 to 80% by weight of vinylidene fluoride/tetrafluoroethylene copolymer and an acrylic ester having a group substituted with a fluorine atom in the side chain as a monomer component. The negatively chargeable developer for electrostatic charge development according to claim 1, wherein the amount is 80 to 20% by weight. (4) The negatively chargeable developer for electrostatic charge development according to claim 1, wherein the toner is a color toner made of a negatively chargeable insulating polyester resin and having a colorant and a charge control agent dispersed in the resin. (5) The volume average diameter of the toner is 4 to 10 μm and 16.
2. The negatively chargeable developer for electrostatic charge development according to claim 1, wherein the proportion of coarse particles of 0 μm or more is 1.0% or less in volume distribution.