JPH05289408A - Electrostatic image developing color toner - Google Patents

Abstract

PURPOSE:To improve the fixability and blocking resistance of the toner without impairing the transparency of a transparency image by using a polysiloxane compd. for the polymerizable color toner. CONSTITUTION:This toner contains a binder resin, coloring agents and the hydrophobic polysiloxane compd. of 30 to 150 deg.Cm.p. having the structure expressed by formula I or formula II. In the formulas I, II, (m), (n) denote natural numbers; X denotes the polyether group expressed by -R1.(R2O)0.(R3O)p.R4, ester group expressed by -O-COR5 or alkoxy group expressed by -OR6, where (o), (p) are natural numbers; each of R1 to R6 is an alkyl group. The blocking resistance and shape holdability of the toner are not sufficient when the m.p. is lower than 30 deg.C. The effect of the release agent is not sufficient when the m.p. is higher than 150 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic charge image developing color toner used in electrophotography, electrostatic recording and the like,
In particular, the present invention relates to a color toner suitable for image formation using a transparency film as a transfer material.

[0002]

2. Description of the Related Art Conventionally, a method for forming a full-color image will be generally described. The photoconductor of the photoconductor drum is uniformly charged by the primary charger, and the image is exposed by the laser light modulated by the magenta image signal of the original, an electrostatic latent image is formed on the photoconductor drum, and magenta toner is retained. The electrostatic latent image is developed by a magenta developing device to form a magenta toner image. Next, the magenta toner image developed on the photosensitive drum is transferred to the transferred transfer material by a transfer charger.

On the other hand, the photosensitive drum after the development of the electrostatic latent image is discharged by the discharging charger, cleaned by the cleaning means, and charged again by the primary charger. Formation of a cyan toner image and transfer of the cyan toner image to the transfer material onto which the magenta toner image has been transferred are performed.
The toner images of four colors are transferred to the transfer material by performing the same procedure as the black color. The transfer material having the four color toner images is fixed by the action of heat and pressure by a fixing roller to form a full color image.

The toner used in the color image forming method needs to have good melting property and color mixing property when heat is applied to it, has a low softening point, and has a low melt viscosity and a sharp melt property. It is preferable to use a high toner.

That is, by using such a sharp melt toner, it is possible to widen the color reproduction range of the copy and obtain a color copy faithful to the original image.

However, such a color toner having a high sharp melting property has a high affinity with the fixing roller,
It tends to be offset to the fixing roller during fixing.

Particularly in the case of a fixing device in a color image forming apparatus, since a plurality of toner layers of magenta, cyan, yellow and black are formed on a transfer material, offset tends to occur particularly easily.

Here, conventionally, in order to improve the releasability of the toner from the fixing roller, the approach from the fixing device side is to apply a releasing agent such as silicone oil to the fixing roller. There is. However, in such an image forming method, the following problems have occurred.

That is, in the existing fixing system in which a releasing agent such as oil is applied to the roller, the structure of the main body is not only complicated, but the oil application has a harmful effect of promoting shortening of the life of the fixing roller. Let's take it.

[0010] Further, in accordance with various copying needs in recent years,
It is widely used to pass film-shaped resin, etc., but the film for overhead projectors, also known as transparency film, is generally well known, but in such a fixing method, a sticky feeling due to oil application is avoided. However, a big problem remains in the quality of the obtained image.

To solve the above problems, various toners containing a releasing agent such as wax have been proposed in order to eliminate the need for oil coating or to reduce the amount of oil coating.

As a general method for producing the above-mentioned toner, conventionally, a wax is added to a fixing resin medium together with a colorant, a charge control agent and other toner components, the mixture is melt-kneaded, and the obtained lumps are finely pulverized. Although produced, in such a method, since the compatibility between the fixing resin and the wax is poor, the proportion of the wax contained is limited, and if the wax is contained in a sufficient proportion, the wax is uniformly dispersed in the toner particles. If the amount of wax added to the toner is different, the particle size of the wax becomes large, and the wax comes to exist on the surface of the toner particles in a free state, which adversely affects the fixing property and blocking resistance of the toner. Thus, it is extremely difficult to obtain a toner in which wax is uniformly dispersed.

Therefore, in order to solve the above-mentioned problems,
JP-A-60-8309, JP-A-60-83040
The publication discloses a method of producing a toner by a so-called polymerization method, in which a wax is contained in a polymerizable monomer and the toner is obtained by polymerizing the polymerizable monomer.

However, the toner produced by this polymerization method can contain a large amount of a release agent such as wax and exhibits advantageous performance during fixing, but when a transparency film is used as the transfer material, fixing is performed. A new problem has arisen that the transparency of the subsequent image is deteriorated.

This is because the wax dispersed in the toner layer on the transfer material seeps out from inside the toner when passing through the fixing roller.
It is considered that the exuded wax covered the image surface or a part of the image surface, and the crystallinity increased with the decrease in temperature after passing through the roller, and the light transmittance was extremely deteriorated. As a result, the full-color image of the transparency film obtained was greyish and had poor color reproducibility.

Further, in the above toner, there is a problem in the dispersibility and compatibility of the wax in the polymerizable monomer. Therefore, if the amount of the releasing agent required for fixing is contained, the amount of the components varies, and the individual toners have different contents. It has not been possible to obtain a toner having satisfactory fixability and blocking resistance.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a color toner for developing an electrostatic charge image, which makes it possible to obtain a full-color transparency sheet having excellent light transmittance of a fixed image. It is in.

Another object of the present invention is to provide a color toner for developing an electrostatic image which is excellent in fixing property and blocking resistance.

[0019]

The greatest feature of the present invention is that it contains at least a binder resin, a colorant and a hydrophobic polysiloxane compound having a structure shown below and a melting point of 30 to 150 ° C. A color toner for developing an electrostatic image.

Further, in the present invention, in the color toner, the compound can be more effective by containing 1 to 50 parts by weight based on 100 parts by weight of the binder resin component in the toner.

Further, the present invention can exert its effect by using a compound having a refractive index at the melting point of 1.30 to 1.90.

The present invention will be described in detail below.

As a result of intensive studies, the present inventors have found that the use of the above polysiloxane compound in a color toner by a polymerization method
It has been found that the fixing property and blocking resistance of the toner can be improved without impairing the transparency of the transparency image. The reason why the transparency is not impaired is not clear, but the compound is in a finely dispersed state in the fixed image, and it is presumed that this prevents crystal growth, which causes deterioration of transparency.

The above compound is preferably hydrophobic in order to maintain the production stability in suspension polymerization.

The melting point of the above compound used in the present invention is
It is preferably from 30 to 150 ° C, more preferably 6
It is 0 to 140 ° C. When the melting point is lower than 30 ° C, the blocking resistance and shape retention of the toner are insufficient, and when the melting point is higher than 150 ° C, the effect of the release agent is insufficient.
The melting point was the temperature of the maximum endothermic peak by DSC.

The heat of fusion ΔH of the above compound used in the present invention is preferably 30 cal / g or less. When the heat of fusion ΔH exceeds 30 cal / g, the low temperature fixability is adversely affected.

The compound in the present invention may be contained in an amount of 1 to 50 parts by weight, preferably 5 to 40 parts by weight, based on 100 parts by weight of the binder resin component in the toner. If it is contained in an amount of more than 50 parts by weight, the production of the polymerized toner becomes unstable and the content of each toner particle is different, so that the blocking resistance is lowered. If the content is not more than 1 part by weight, more preferably not less than 5 parts by weight, the effect of the compound will not be exhibited and the fixability will be lowered.

The finely dispersed compound has a refractive index at the melting point of 1.40 to 1.70, preferably 1.45 to 1.6.
It is 0. If the refractive index is out of the above range, the refractive index is significantly different from that of the binder resin, which impedes the straightness of the transmitted light in the fixed image and scatters the light, resulting in a gray image in the transmitted light of the fixed image. turn into.

The alkyl chain R in the above compound used in the present invention may be any linear or branched alkyl compound having 1 to 100 carbon atoms, and has solubility in monomers and hydrophobicity of the above compound. From the viewpoint of imparting, a prime number of 1 to 50 is preferable.

In the present invention, a low softening point wax is used in combination with the polysiloxane compound of the present invention,
Further, the fixing property (offset resistance) is excellent, and the transparency of the transparency film image is not deteriorated.

As the low softening point wax used in the present invention, any wax having a releasing effect may be used. Paraffin / polyolefin wax and modified products thereof, for example, oxides and graft treated products. In addition to these, higher fatty products, their metal salts, amide wax, and the like are included. These waxes are ring and ball method (JIS K253
The softening point according to 1) is 40 to 130 ° C., preferably 50 to 130 ° C.
Those having a temperature of 120 ° C. are desirable, and when the softening point is lower than 40 ° C., the blocking resistance and shape retention of the toner are insufficient, and when the softening point is higher than 130 ° C., the effect of releasability becomes insufficient. The amount of these release agents added is generally preferably 10 to 80 parts by weight per 100 parts by weight of the polymerizable monomer.

As the polymerizable monomer constituting the polymerizable monomer system used in the present invention, and the toner property imparting agent such as colorant, the followings can be mentioned.

Examples of the polymerizable monomer include styrene-based monomers such as styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene and p-ethylstyrene, methyl acrylate and acryl. Ethyl acetate, n-butyl acrylate, isobutyl acrylate, n-propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, etc. Acrylic esters, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, methacrylic acid Phenyl, dimethylaminoethyl methacrylate, methacrylic acid esters other acrylonitrile such as ethyl methacrylate aminoethyl, methacrylonitrile, and the like monomers acrylamide.

These monomers may be used alone or in combination. Among the above-mentioned monomers, it is preferable to use styrene or a styrene derivative alone or in a mixture with other monomers, from the viewpoint of developing characteristics and durability of the toner.

In the present invention, a polar resin may be added to the monomer system for polymerization. The polar resins that can be used in the present invention are exemplified below. (1) Examples of the cationic polymer include polymers of nitrogen-containing monomers such as dimethylaminoethyl methacrylate and diethylaminoethyl methacrylate, and copolymers with styrene and unsaturated carboxylic acid esters. (2) Examples of the anionic polymer include nitrile monomers such as acrylonitrile, halogen-containing monomers such as vinyl chloride, unsaturated carboxylic acids such as acrylic acid and methacrylic acid,
Other unsaturated dibasic acids / unsaturated dibasic anhydrides, polymers such as nitro-based monomers or copolymers with styrene-based monomers and the like can be mentioned. These polar resins localize near the surface of the toner to improve the blocking resistance of the toner.

As the coloring agent used in the present invention, known coloring agents can be used. For example, carbon black, iron black, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Mordant Red 30, C.I.
I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Mordant Blue 7, C.I. I.
Direct Green 6, C.I. I. Basic Green 4, C.I. I. Dyes such as Basic Green 6, Yellow Lead, Cadmium Yellow, Mineral Fast Yellow, Navel Yellow, Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NCG, Tartrazine Lake, Molybdenum Orange, Permanent Orange GT
R, benzidine orange G, cadmium red, permanent red 4R, watching red calcium salt,
Brilliant Carmine 3B, Fast Violet B,
There are pigments such as methyl violet lake, dark blue, cobalt blue, alkali blue lake, Victoria blue lake, quinacridone, rhodamine lake, phthalocyanine blue, fast sky blue, pigment green B, malachite green lake, and final yellow green G. In the present invention, since a toner is obtained by using a polymerization method, it is necessary to pay attention to the polymerization inhibitory property and the water phase transfer property of the colorant, and preferably surface modification, for example,
It is better to apply a hydrophobic treatment with a substance that does not inhibit polymerization. In particular, since many dyes and carbon black have a polymerization inhibitory property, caution is required when using them. A preferred method of surface-treating the dye system is a method of polymerizing a polymerizable monomer in the presence of these dyes in advance, and the obtained colored polymer is added to the monomer system. Further, the carbon black may be subjected to a treatment similar to the above dye, or a graft treatment with a substance that reacts with the surface functional group of the carbon black, such as polyorganosiloxane.

In the present invention, a magnetic substance may be added,
This is also preferably used after being surface-treated.

In the present invention, it is desirable to add a charge control agent to the toner material in order to control the chargeability of the toner. As these charge control agents, among known ones, those having almost no polymerization inhibitory property / water phase transfer property are used. For example, as a positive charge control agent, a nigrosine dye, a triphenylmethane dye, a quaternary ammonium salt, an amine is used. Examples of the negative charge control agent include metal-containing salicylic acid compounds, metal-containing monoazo dye compounds, styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, and the like.

As the polymerization initiator, any suitable polymerization initiator, for example, 2,2'-azobis- (2,4-dimethylvaleronitrile), 2,2'-azobisisobutyronitrile, 1, 1'-azobis (cyclohexane-1-
Carbonitrile), 2,2′-azobis-4-methoxy-2,4-dimethylvaleronitrile, azobis or diazo polymerization initiators such as azobisisobutylnitrile, benzoyl peroxide, methyl ethyl ketone peroxide,
Examples thereof include peroxide-based polymerization initiators such as diisopropyl peroxycarbonate, cumene hydroperoxide, 2,4-dichlorobenzoyl peroxide and lauroyl peroxide. These polymerization initiators are preferably added in an amount of 0.5 to 20% by weight of the polymerizable monomer.

In the present invention, a crosslinking agent may be added, and the preferable addition amount is 0.001 to 15% by weight.

The additives used in the present invention for imparting various characteristics are, from the viewpoint of durability when added to the toner,
The particle diameter is preferably 1/10 or less of the weight average diameter of the toner particles. The particle size of the additive means the average particle size thereof obtained by observing the surface of the toner particles with an electron microscope. As the additives for the purpose of imparting these characteristics, for example, the following ones are used.

1) Flowability-imparting agents: metal oxides (silicon oxide, aluminum oxide, titanium oxide, etc.), carbon black, carbon fluoride, etc. It is more preferable that each is subjected to a hydrophobic treatment.

2) Abrasives: metal oxides (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitrides (silicon nitride, etc.), carbides (silicon carbide, etc.), metal salts (calcium sulfate, etc.) , Barium sulfate, calcium carbonate, etc.) etc.

3) Lubricants: Fluorine-based resin powders (vinylidene fluoride, polytetrafluoroethylene, etc.), fatty acid metal salts (zinc stearate, calcium stearate, etc.), etc.

4) Charge controllable particles: metal oxides (tin oxide, titanium oxide, zinc oxide, silicon oxide, aluminum oxide, etc.), carbon black, etc.

These additives are used in an amount of 0.1 to 10 parts by weight, preferably 100 parts by weight of toner particles.
0.1-5 parts by weight are used. These additives may be used alone or in combination.

The aqueous medium used in the present invention includes:
In each case, a suitable stabilizer is added. For example, as the inorganic compound, calcium phosphate, magnesium phosphate, aluminum phosphate, zinc phosphate, calcium carbonate, magnesium carbonate, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, bentonite, Examples thereof include silica and alumina. As the organic compound, polyvinyl alcohol, gelatin, methyl cellulose, methyl hydroxypropyl cellulose, ethyl cellulose, sodium salt of carboxymethyl cellulose, polyacrylic acid and its salt, starch and the like can be dispersed in an aqueous phase and used. This stabilizer is based on 100 parts of the polymerizable monomer,
It is preferred to use 0.2 to 20 parts by weight.

Further, 0.001 to 0.1 part by weight of a surfactant may be used for finely dispersing these stabilizers. This is for promoting the intended action of the above dispersion stabilizer, and specific examples thereof include sodium dodecylbenzene sulfate, sodium tetradecyl sulfate, sodium pentadecyl sulfate, sodium octyl sulfate,
Examples thereof include sodium oleate, sodium laurate, potassium stearate, calcium oleate and the like.

When an inorganic compound is used among these dispersion stabilizers, a commercially available one may be used as it is, but in order to obtain finer particles, the inorganic compound may be produced in an aqueous medium.

For example, in the case of calcium phosphate, it is advisable to mix the sodium phosphate aqueous solution and the calcium chloride aqueous solution under high stirring.

The polymerized toner used in the present invention is obtained by the following method. That is, a polysiloxane compound used in the present invention, a colorant, a charge control agent, a polymerization initiator, a low softening point wax, and other additives are added to a polymerizable monomer, and a homogenizer / ultrasonic dispersion is added. The monomer system uniformly dissolved or dispersed by a machine or the like is dispersed in an aqueous medium containing a dispersion stabilizer by a stirrer, a homomixer homogenizer or the like. Preferably the monomer droplets are of the desired toner particle size, typically 30.
Granulate by adjusting the stirring speed and time so as to have a particle size of μm or less. After that, stirring may be performed to the extent that the particle state is maintained and the particles are prevented from settling / floating by the action of the dispersion stabilizer. After completion of the reaction, while adding the aqueous medium to the suspension, the aqueous medium is distilled off to remove the dispersion stabilizer,
The produced toner particles are collected by washing and filtration and dried. In the suspension polymerization method, it is usually preferable to use 300 to 3000 parts by weight of water as a dispersion medium with respect to 100 parts by weight of the monomer system.

In the above step, the polymerization temperature is set to 40 ° C. or higher, generally 50 to 90 ° C. to carry out the polymerization. Further, the temperature may be raised in the latter half of the polymerization reaction.

When the toner of the present invention is used in combination with a carrier as a two-component developer, an electrically insulating resin is used as a coating resin for the surface of the carrier, which is appropriately selected depending on the toner material and carrier core material. .. In the present invention, at least one monomer selected from at least acrylic acid (or its ester) monomer and methacrylic acid (or its ester) monomer in order to improve the adhesion to the surface of the carrier core material. It is desirable to contain In particular, when polyester resin particles having a high negative chargeability are used as the toner material, it is preferable to use a copolymer with a styrene-based monomer for the purpose of stabilizing the charge. Is preferably 5 to 70% by weight.

As the monomer for the resin for coating the carrier core material which can be used in the present invention, as the styrene-based monomer,
For example, styrene monomer, chlorostyrene monomer, α
-Methylstyrene monomer, styrene-chlorostyrene monomer and the like, and examples of acrylic monomers include acrylic acid ester monomers (methyl acrylate monomer, ethyl acrylate monomer, butyl acrylate monomer, octyl acrylate monomer, phenyl acrylate monomer). , Acrylic acid 2 ethylhexyl monomer) and the like, and methacrylic acid ester monomers (methyl methacrylate monomer, ethyl methacrylate monomer, butyl methacrylate monomer, phenyl methacrylate monomer) and the like.

The carrier core material (magnetic particles) used in the present invention includes, for example, surface-oxidized or unoxidized metals such as iron, nickel, copper, zinc, cobalt, manganese, chromium, rare earths, and alloys or oxides thereof. Things can be used.
Moreover, there is no particular limitation in the manufacturing method. Preferably, it contains 98 wt% or more of a ferrite carrier having a metal composition ratio of 5 to 20: 5 to 20:30 to 80 (weight ratio).

Next, the color image forming method according to the present invention will be described.

FIG. 1 is a schematic sectional view of an electrophotographic apparatus capable of forming a full-color image according to the present invention. In the drawing, a transfer material conveying system I is provided from the right side of the apparatus main body 100 (right side in FIG. 1) to a substantially central portion of the apparatus main body 100, and the transfer material conveying system I is provided at a substantially central portion of the apparatus main body 100. The latent image forming section II provided near the transfer drum 8 and the developing means (that is, the rotary developing device III) provided near the latent image forming section II. Broadly divided. The transfer material transport system I described above is used in the apparatus main body 100.
Transfer material supply trays 101 and 102, which are detachable from the opening formed on the right side of FIG. 1 (right side of FIG. 1), and supply rollers 103 and 104 disposed substantially directly above the trays 101 and 102. And paper feed guides 4A and 4B provided near the paper feed rollers 103 and 104 and provided with the paper feed roller 106, and provided near the paper feed guide 4b. The contact roller 7, the gripper 6, the transfer material separating charger 12, and the separating claw 14 are arranged from the upstream side to the downstream side, and the transfer charger 9 and the transfer material separating charge are provided on the inner peripheral side. A container 13 is provided. The transfer drum 8 rotatable in the direction of the arrow in FIG. 1 and the conveyor belt means 1 provided near the separating claw 14.
5 and the apparatus main body 1 which is disposed close to the end of the conveyor belt means 15 in the conveying direction and extends outside the apparatus main body 100.
00, a discharge tray 17 that is removable and a fixing device 16 that is adjacent to the discharge tray 17.

The latent image forming section II has an image bearing member (that is, the photoconductor drum 2) whose outer peripheral surface abuts on the outer peripheral surface of the transfer drum 8 and is rotatable in the direction of the arrow in FIG. A static elimination charger 10, a cleaning unit 11, a primary charger 3, and the photosensitive member, which are disposed near the outer peripheral surface of the photosensitive drum 2 from the upstream side to the downstream side in the rotation direction of the photosensitive drum 2. The drum 2 is provided with an image exposure means such as a laser beam scanner for forming an electrostatic latent image on the outer peripheral surface and an image exposure reflection means such as a polygon mirror. The rotary developing device III includes a rotatable housing (hereinafter referred to as "rotating body") 4a, and the photosensitive drum at a position which is mounted in each of the rotating bodies 4a and faces the outer peripheral surface of the photosensitive drum 2. 2, a yellow developing device 4Y, a magenta developing device 4M, and a cyan developing device 4 which are configured to visualize (that is, develop) the electrostatic latent image formed on the outer peripheral surface of 2.
C and a black developing device 4BK.

The sequence of the entire image forming apparatus having the above configuration will be described by taking the case of the full color mode as an example. When the photoconductor drum 2 described above rotates in the direction of the arrow in FIG. 8, the photoconductor on the photoconductor drum 2 is uniformly charged by the primary charger 3. When the photoconductor is uniformly charged by the primary charger 3, a document (not shown)
Image exposure is performed by the laser light E modulated by the yellow image signal of No. 3, an electrostatic latent image is formed on the photoconductor drum 2, and the yellow developing device 4Y previously placed at the developing position by the rotation of the rotating body 4a. The electrostatic latent image is developed by.

On the other hand, the paper feed guide 4A and the paper feed roller 10
6. The transfer material conveyed through the paper feed guide 4b is held by the gripper 6 at a predetermined timing,
It is electrostatically wound around the transfer drum 8 by the contact roller 7 and the opposing electrode. The transfer drum 8 rotates in the direction of the arrow in FIG. 1 in synchronism with the photoconductor drum 2, and the visible image developed by the yellow developing device 4Y is the outer peripheral surface of the photoconductor drum 2 and the outer periphery of the transfer drum 8. The image is transferred by the transfer charger 9 at the portion in contact with the surface. The transfer drum 8 continues to rotate and is ready for transfer of the next color (magenta in FIG. 1).

On the other hand, the photoconductor drum 2 is decharged by the decharging charger 10 and cleaned by the cleaning means 11 and then recharged by the primary charger 3 so that the next magenta image signal causes the image as described above. Receive exposure. The rotary developing device rotates while the electrostatic latent image based on the magenta image signal is formed on the photoconductor drum 2 by the image exposure to set the magenta developing device 4M at the predetermined developing position. Perform predetermined magenta development. Subsequently, the above-described process is performed for cyan and black, respectively, and when the transfer of four colors is completed, the multicolor image formed on the transfer material is transferred to the chargers 12, 13 respectively. The gripping of the transfer material by the gripper 6 is released, and the transfer material is separated from the transfer drum 8 by the separating claw 14 and sent to the fixing device 16 by the conveyor belt 15 and fixed by heat and pressure. Then, a series of full-color print sequences is completed, and a required full-color print image is formed.

The fixing device 16 includes a heat fixing roller 161 and a pressure roller 162. Heating roller 161
Preferably has a surface layer having excellent release characteristics. The surface layer of the pressure roller 162 is preferably formed of the same resin as that of the heating roller.

The present invention will be specifically described based on the following examples.

[0064]

EXAMPLE 1 451 g of 0.1 M Na ₃ PO ₄ aqueous solution was added to 709 g of ion-exchanged water and heated to 60 ° C., and then 12,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo). It was stirred at. A 1.0 M-CaCl ₂ aqueous solution 67.
7 g was gradually added to obtain an aqueous medium containing Ca ₃ (PO ₄ ) ₂ .

The above formulation was heated to 60 ° C. and 12,000 rpm using a TK type homomixer (made by Tokushu Kika Kogyo).
Were uniformly dissolved and dispersed. In addition to this, a polymerization initiator, 2,
2'-azobis (2,4-dimethylvaleronitrile) 1
0 g and 1 g of dimethyl 2,2′-azobisisobutyrate were dissolved to prepare a polymerizable monomer system. The polymerizable monomer system was added to the aqueous medium, and the mixture was subjected to 10,000 r with a TK homomixer at 60 ° C. under N ₂ atmosphere.
The polymerizable monomer system was granulated by stirring at pm for 20 minutes. Then, while stirring with a paddle stirring blade, the reaction was carried out at 60 ° C. for 3 hours, then the liquid temperature was adjusted to 80 ° C. and the reaction was carried out for 10 hours.

Then, the mixture is cooled, hydrochloric acid is added, and Ca ₃ (P
O ₄ ) ₂ was dissolved, filtered, washed with water and dried to obtain a polymerized toner. The particle diameter of the obtained toner is 8.5μ.
m had a sharp particle size distribution.

With respect to 100 parts by weight of the obtained toner, B
0.7 part of hydrophobic silica having a specific surface area of 200 m ² / g by the ET method was externally added. To 7 parts of this toner, 93 parts of an acrylic-coated ferrite carrier was mixed,
Used as a developer.

A polyethylene terephthalate (hereinafter PET) film was used as the transfer material.

Using this developer and the externally added toner, images were printed by a full-color copying machine CLC-500 modified by Canon.

The developing condition was a developing contrast of 320 V under the environment of 23 ° C./65%. The unfixed image just developed and transferred by a modified CLC-500 machine was fixed by an external fixing machine having no oil coating function. Fixing speed is 2
It was set to 0 mm / sec.

The obtained fixed image was a transparency image having excellent fixability without offset. Furthermore, when actually projected with an overhead projector, it was a cyan image with excellent transparency (results are shown in Table 1).

Example 2 The same operation as in Example 1 was repeated except that the colorant component and the polysiloxane compound were changed as follows, to obtain a polymerized toner having a weight average diameter of 7.9 μm. ..

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was not offset and was a transparency image excellent in fixability. Furthermore, when actually projected with an overhead projector, it was a yellow image with excellent transparency (the results are shown in Table 1).

Example 3 The same operation as in Example 1 was repeated except that the polysiloxane compound formulation was changed as follows to obtain a polymerized toner having a weight average diameter of 8.3 μm.

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was a transparency image having excellent fixability without offsetting. Furthermore, when projected with an overhead projector, the image was excellent in transparency (the results are shown in Table 1).

Comparative Example 1 The same operation as in Example 1 was carried out except that the polysiloxane compound in the formulation of Example 1 was changed as follows.
A polymerized toner having a weight average diameter of 8.8 μm was obtained.

When the obtained toner was fixed in the same manner as in Example 1, a transparency image excellent in light transmission was obtained, but toner having blocking resistance lower than that in Example 1 was obtained. (Results are shown in Table 1).

COMPARATIVE EXAMPLE 2 The same procedure as in Example 1 was repeated except that 30 g of paraffin wax having a melting point of 65 ° C. was used instead of the polysiloxane compound, and the weight average diameter was 7.7 μm.
m polymerization method toner was obtained.

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was a transparent image having excellent fixability without offset.

However, when actually projected with an overhead projector, the transparency was poor.

Example 4 The same operation was performed except that the content of the polysiloxane compound in the formulation of Example 1 was 10 g and the polyolefin wax was 30 g, and the weight average diameter was 8.2 μm.
A polymerized toner of m was obtained.

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was not offset and was a transparency image excellent in fixability. Furthermore, when actually projected with an overhead projector, it was a cyan image with excellent transparency (results are shown in Table 1).

Example 5 The same procedure as in Example 1 was carried out except that the colorant component and the polysiloxane compound were modified as follows and 35 g of paraffin wax was added, and the weight average diameter was 7.9 μm. A polymerized toner of

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was not offset and was a transparency image excellent in fixability. Furthermore, when actually projected with an overhead projector, it was a yellow image with excellent transparency (the results are shown in Table 1).

Example 6 The same procedure as in Example 1 was repeated except that the polysiloxane compound was modified as follows and 30 g of the polyolefin wax was added, and the weight average diameter was 8.
A polymerized toner of 3 μm was obtained.

When the obtained toner was fixed in the same manner as in Example 1, the obtained fixed image was a transparency image having excellent fixability without offset. Furthermore, when projected with an overhead projector, the image was excellent in transparency (the results are shown in Table 1).

[0087]

[Table 1] Light transmittance: ○ Practically excellent △ Practical use × Practically impossible Fixing area: Unfixed image developed and transferred by a modified CLC-500 machine, but not applied to an external fixing machine And a fixing test was conducted. The above is the fixing possible temperature.

(Temperature is 5 ° C., process speed is 9
0 mm / sec) Blocking resistance: After leaving in a constant temperature bath at 50 ° C. for 3 days,
A blocking test was performed.

○ Practically usable × Not practically usable

[0090]

According to the present invention, by using the above polysiloxane compound in the color toner by the polymerization method, the fixing property and blocking resistance of the toner can be improved without impairing the transparency of the transparency image.

Further, if a low softening point wax is used, the fixing property can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an electrophotographic apparatus capable of forming a full-color image.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G03G 9/087 15/01 J // C08L 83/06 LRR 8319-4J 83/12 G03G 9/08 384 (72 ) Inventor Kasuya Precious 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuyuki Miyano 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (6)

[Claims] 1. A color toner for developing an electrostatic charge image, which comprises at least a binder resin, a colorant, and a hydrophobic polysiloxane compound having a structure shown below and having a melting point of 30 to 150 ° C. 2. The color toner for developing an electrostatic charge image according to claim 1, which contains a low softening point wax. 3. The color toner for developing an electrostatic charge image according to claim 1, which is obtained by a suspension polymerization method. 4. The content of the polysiloxane compound is
The color toner for developing an electrostatic charge image according to any one of claims 1 to 3, wherein the amount is 1 to 50 parts by weight with respect to 100 parts by weight of the binder resin. 5. The electrostatic charge image according to claim 2, wherein the content of the low softening point wax is 10 to 80 parts by weight with respect to 100 parts by weight of the binder resin. Color toner for development. 6. The refractive index of the polysiloxane compound is
6. The color toner for developing an electrostatic charge image according to claim 1, wherein the color toner is 1.30 to 1.90.