JPH07120962A - Thermal fixation toner and thermal fixation method using the same - Google Patents

Abstract

PURPOSE:To obtain a fixed image having excellent fixation properties without coating with oil and without adversely affecting the transparency by using a toner contg. a specific polysiloxane compound. CONSTITUTION:In this fixation method, a pair of rollers, each of which has the anti-offset layer 23 on the elastic layer 24 that is formed on the roller base material 25, are provided to fix an unfixed toner image on the recording medium. The toner used for this fixation method is a color toner which is produced by the suspension polymerization process and contains the polysiloxane compound that is represented by the formula I or II and has a 30 to 150 deg.C melting point and a refractive index of 1.30 to 1.90. The anti-offset layer 23 is formed out of a silicone resin. In the formula I and II, X is a polyether group represented by the formula -R1(R2O)j(R3O)kR4 (wherein each of R1 to R4 is an alkyl group and (j) and (k) are natural numbers), an ester group represented by the formula -O-COR5 (wherein R5 is an alkyl group) or an alkoxyl group represented by the formula -OR6 (wherein R6 is an alkyl group) and (m) and (n) are natural numbers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to electrophotography / electrostatic printing,
The present invention relates to a method for fixing a visible image formed by a toner in magnetic recording or the like on a recording material, and a toner used in the fixing method.

[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 to form an electrostatic latent image on the photoconductor drum, which holds magenta toner. The electrostatic latent image is developed by a magenta developing device to form a magenta toner image. Then, 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 then 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. A full-color image is formed by fixing the transfer material having the toner images of four colors by the action of heat and pressure by a fixing roller.

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, and has a low softening point and a low melt viscosity. It is preferable to use a high toner.

That is, by using such a sharp melt toner, the color reproduction range of a copy can be widened and a color copy faithful to the original image can be obtained.

However, such a color toner having a high sharp melt property has a high affinity with the fixing roller and 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, as an approach from the fixing device side, a releasing agent such as silicone oil is applied 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, not only the structure of the main body becomes complicated, but also this oil application promotes shortening of the life of the fixing roller. The harmful effects of

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

To solve the above problems, various toners containing a release 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, the compatibility between the fixing resin and the wax is poor, so that the proportion of the wax contained is limited, and if the wax is contained in a sufficient proportion, the wax is uniformly dispersed. 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 for 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 deteriorates.

On the other hand, in the full-color electrophotographic method which generally requires development of a plurality of times and superposition of several kinds of toner layers of different colors on the same support, it is a necessary condition for the binder resin for color toner. Includes the following items. (1) The fixed toner needs to be in a state of almost completely melted so that the shape of the toner particles cannot be discriminated so as not to diffusely reflect light and prevent color reproduction. (2) It must be a binder resin having transparency that does not interfere with the toner layers of different tones underneath the toner layer.

As described above, for a mono-color copying machine, it is desired to develop a binder resin for toner having a wide fixing temperature range and a high offset resistance, and for a full-color copying machine, not only a wide fixing temperature range but also a resin. And the flatness of the fixing surface when fixed.

Further, in recent years, from mono-color to full-color copying machines, there have been many demands for speeding up, shortening of heat-up time of heating rollers, reduction of power consumption, and the like.

In order to satisfy these requirements, a binder for toner which can be fixed at a low temperature and has a wide fixing area, excellent transparency, and a flat fixing surface when fixed as described above. Resin required.

A method of using a pressure fixing toner is also conceivable here, but in this method, when used as a full-color toner which reproduces colors by superimposing three colors or four colors, the binder resin does not melt, and thus the color mixing property is caused. Results in a poorly-colored and dull image. Therefore, in the fixing step, heat must be applied to the extent that the binder resin is melted and the colors can be mixed.

It is possible to reduce the melt viscosity of the binder resin for toner only for the purpose of fixing at low temperature. For example, there is a method of lowering the molecular weight of the resin or the glass transition point, but this method deteriorates the storage stability of the toner,
This causes phenomena such as blocking of toner particles and fusion of toner to a developing drum.

For the purpose of expanding the fixing temperature of conventional vinyl polymers, JP-A-58-14148 and JP-A-5-148148
8-72948, JP-A-59-174855-6
Japanese Patent Publication No. 60-123855, Japanese Patent Publication No. 52
No. 3,304,5, Japanese Patent Publication No. 57-52574, Japanese Patent Publication No. 58-8505 and the like disclose methods of using an offset preventive agent, but these are auxiliary, especially for monocolor toners. When the toner is used as a full-color toner, the color mixing property deteriorates.

Further, Japanese Patent Application Laid-Open No. 56-158340,
JP-A-58-86558, JP-A-58-2034
53, JP-A-59-88748, JP-A-5
9-226358, JP-A-60-45259, JP-A-60-45261, and JP-A-60-46.
In Japanese Patent No. 566, Japanese Patent Publication No. 60-2411, etc.,
A binder resin for a toner having a low molecular weight component and a high molecular weight component is disclosed. By using these resins,
It has become possible to expand the fixing temperature to some extent, but due to the presence of high-molecular weight components such as gel, the pulverizability decreases in the general toner manufacturing method, and the melt viscosity during heat kneading becomes too high, which causes problems. However, even in the polymerization method, there is a manufacturing problem in encapsulating a high molecular weight component so that the fixability is satisfied. Further, particularly when it is used as a full-color toner, the smoothness of the fixing surface when fixed is impaired, and thus the color mixing property deteriorates.

That is, it is extremely difficult to fix the toner at a low temperature, expand the fixing temperature range, and simultaneously satisfy the toner characteristics of storage stability, fluidity, durability, transparency, and smoothness of the fixing surface. .

For this reason, it is important to match the toner used and the fixing device configuration.

[0025]

SUMMARY OF THE INVENTION An object of the present invention is to provide a heat fixing toner and a heat fixing method using the toner, in which these problems are improved.

That is, an object of the present invention is to provide a heat fixing toner which can be fixed at a low temperature, has a wide fixing temperature range and can be fixed without applying oil, and a heat fixing method using the toner. .

Still another object is to provide a color toner capable of obtaining a transparency sheet fixed image without impairing transparency.

[0028]

The object of the present invention can be achieved by the following constitutions.

That is, a heat fixing method for fixing an unfixed toner image on a recording material, which is provided with a fixing roller having an elastic layer on a roller base material and an offset prevention layer on the elastic layer, and a heat fixing method applied to the method. In the heat fixing toner which can be used, the toner is the following general formula (1) or (2):

[0030]

[Chemical 3]

[In the formula, X is -R ₁ (R ₂ O) _j (R ₃
O) _k R ₄ (R _{1 to} R ₄ are alkyl groups, j and k are natural numbers), a polyether group represented by —O—COR ₅ (R ₅
Is an alkyl group) or an ester group represented by -OR ₆
(R ₆ is an alkyl group) is an alkoxy group. M and n are natural numbers. ], The melting point is 3
A suspension polymerization method color toner containing a polysiloxane compound having a refractive index of 1.30 to 1.90 at 0 to 150 ° C., wherein the offset prevention layer is formed of a silicone resin. To be achieved.

R _{1 to} R ₆ in the above formula may be any of linear or branched alkyl compounds having 1 to 100 carbon atoms, which have solubility in monomers and impart hydrophobicity to the compounds. From the point of view, those having 1 to 50 carbon atoms are preferable. Further, j and k are preferably 1 to 20, and m and n are preferably 1 to 30.

The present invention will be described in detail below.

As a result of earnest studies, the inventors of the present invention have found that, with the above-mentioned structure, a fixed image having excellent fixability can be obtained without applying oil and without impairing the transparency of the transparency image. .

Explaining the cause of this, a polysiloxane compound of the general formula (1) or (2) which is a release agent,
The fixing roller that uses silicone resin as the offset layer is
It has a good affinity and is capable of uniformly exerting the releasing effect. Furthermore, unlike other waxes (polyolefin type, paraffin type, etc.), the polysiloxane compound itself has low crystallinity and excellent transparency. In addition, even when the polysiloxane compound and other wax component are used in combination, the crystal growth of the wax component is inhibited and fine crystallization occurs.

Further, since the toner containing the polysiloxane compound is a toner obtained by a suspension polymerization method, it can contain a sufficient amount for fixing property without impairing blocking resistance.

The melting point of the polysiloxane compound of the general formula (1) or (2) used in the present invention is 30 to 150 ° C.
Is preferable, and more preferably 60 to 140 ° C. If the melting point is lower than 30 ° C, the blocking resistance and shape retention of the toner are not sufficient, and if the melting point is higher than 150 ° C, the effect of releasability is not sufficient. The melting point is
The temperature was the maximum endothermic peak by DSC.

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

The polysiloxane compound in the present invention is contained in an amount of 1 to 50 parts by weight, preferably 5 to 40 parts by weight, per 100 parts by weight of the monomer component in the toner.

When the content is 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 5 parts by weight or more, the effect of the compound will not be exhibited and the fixability will decrease.

The finely dispersed polysiloxane compound preferably has a refractive index at the melting point of 1.40 to 1.70, more preferably 1.45 to 1.60. If the refractive index is out of the above range, the straightness of the transmitted light in the fixed image is obstructed because the refractive index is greatly different from that of the binder resin, and the light is scattered.As a result, the transmitted light image of the fixed image becomes gray. turn into.

In the present invention, for the purpose of further improving the releasability at the time of heat roll fixing, waxes generally used as a releasing agent such as a hydrocarbon compound may be added to the toner. Examples of waxes used in the present invention include paraffin / polyolefin waxes and modified products thereof, for example, oxides and graft-treated products, higher fatty acids, metal salts thereof, and amide waxes. 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 if the softening point is less than 40 ° C., the blocking resistance and shape retention of the toner are insufficient, and if it exceeds 130 ° C., the effect of releasability becomes insufficient. The amount of the release agent added is generally preferably 1.0 to 100 parts by weight per 100 parts by weight of the polymerizable monomer. The polysiloxane compound is used as the release agent 1
It is preferable that the amount is 100 parts by weight or less with respect to 00 parts by weight.

Examples of the polymerizable monomer constituting the polymerizable monomer system used in the toner of the present invention and the toner property imparting agent such as a colorant include the following.

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 combination with other monomers, from the viewpoint of developing characteristics and durability of the toner.

In the present invention, a resin having a polar group 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 examples include unsaturated dibasic acids / unsaturated dibasic anhydrides, polymers such as nitro monomers, and copolymers with styrene monomers. These polar resins localize near the surface of the toner to improve the blocking resistance of the toner.

As the colorant used in the present invention, known colorants 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 for surface-treating a 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 the same treatment as the above-mentioned dye, or to a graft treatment with a substance that reacts with the surface functional group of the carbon black, for example, polyorganosiloxane.

In the present invention, a magnetic substance may be added,
It is also preferable that this is also subjected to a surface treatment before use.

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 azobisisobutyronitrile, 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. The amount of these polymerization initiators added is preferably 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, in terms 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 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. Those subjected to a hydrophobic treatment are more preferable.

2) Abrasive: metal oxide (strontium titanate, cerium oxide, aluminum oxide, magnesium oxide, chromium oxide, etc.), nitride (silicon nitride, etc.), carbide (silicon carbide, etc.), metal salt (calcium sulfate, etc.) , Barium sulfate, calcium carbonate, etc.) etc.

3) Lubricants: Fluorine-based resin powder (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 the 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:
Add a suitable stabilizer. 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. The stabilizer is 0.2 per 100 parts by weight of the polymerizable monomer.
It is preferred to use ˜20 parts by weight.

For fine dispersion of these stabilizers, 0.001 to 0.1 part by weight of surfactant may be used. This is for promoting the intended action of the 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 product may be used as it is, but the inorganic compound may be produced in an aqueous medium in order to obtain finer particles. 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, the polysiloxane compound used in the present invention, a low softening point wax, a colorant, a charge control agent, a polymerization initiator and other additives are added to the polymerizable monomer, and the mixture is homogenized by a homogenizer / ultrasonic disperser or the like. The dissolved or dispersed monomer system is dispersed in an aqueous medium containing a dispersion stabilizer by a usual stirrer, homomixer / homogenizer or the like. Granulation is preferably carried out by adjusting the stirring speed and time so that the monomer droplets have a desired toner particle size, generally 30 μm or less. After that, by the action of the dispersion stabilizer, the particle state is maintained,
In addition, stirring may be performed to the extent that settling / floating of particles is prevented. After completion of the reaction, the aqueous medium is distilled off while adding the aqueous medium to the suspension to remove the dispersion stabilizer, and the produced toner particles are collected by washing / filtration and dried. In the suspension polymerization method, 3 parts of water is usually added to 100 parts by weight of the monomer system.
It is preferable to use 0.00 to 3000 parts by weight as a dispersion medium.

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

On the other hand, as an example of the roller structure of the fixing device used in the present invention, as shown in FIG. 1, an elastic layer is formed on a roller base material, and an offset prevention layer is formed on the elastic layer 24. It has a fixing roller formed by forming 23.

Although various materials can be used for the elastic layer 24, methylphenyl HTV silicone rubber, which is excellent in tensile strength, thermal conductivity, elastic modulus and adhesion to the core metal 25, is preferable. Methylphenyl HTV silicone rubber having high thermal conductivity is preferable. This is because the elastic layer 24 has a high thermal conductivity, so that heat is quickly supplied to the surface of the fixing roller to prevent the surface temperature of the fixing roller from lowering due to the passage of the recording material P, and the heat is applied to the recording material P. This is because the carried unfixed toner image T can be stably fixed in temperature.

Particularly in fixing a full-color image, the surface temperature of the fixing roller has a great influence on the color mixture of the toner, and the change in the surface temperature has an influence on the tint of the color image. Therefore, it is particularly preferable to form the elastic layer from methylphenyl HTV silicone rubber having high thermal conductivity.

The thermal conductivity of the elastic layer is 0.4 × 10 ⁻³ or more.
It is preferably 1.5 × 10 ⁻³ cal / cm · sec · ° C., more preferably 1.0 × 10 ⁻³ cal / cm · se.
c ・ ° C is good.

A silicon resin is used for the offset prevention layer in the present invention.

Specifically, LTV silicone rubber can be used in addition to RTV silicone rubber. The RTV silicone rubber may be either one-component or two-component, but it is preferable to use one-component RTV silicone rubber. This is because the one-component RTV silicone rubber has adhesiveness to the mating substance before vulcanization, and finally can firmly adhere to the elastic layer of the offset prevention layer. A filler such as silica or stalk may be appropriately mixed in the offset prevention layer.

The offset preventing layer is preferably formed by applying rubber such as LTV silicone rubber or RTV silicone rubber by knife coating or spray coating. This is because when an application method such as knife coating or spray coating is used, the offset preventing layer is easily formed as a thin layer due to the free liquid surface of the applied rubber such as LTV silicone rubber or RTV silicone rubber. This is because it is easy to set up a manufacturing device for forming a sheet, and is excellent in mass productivity of the fixing roll. Further, the release property of the offset prevention layer is also stable.

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

FIG. 2 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 of FIG. 2) 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 portion II provided near the transfer drum 8 and the developing means (that is, the rotary developing device III) disposed near the latent image forming portion II. Broadly divided. The transfer material transport system I described above is used in the apparatus main body 100.
The transfer material supply trays 101 and 102 that are detachable from the opening formed on the right side of FIG. 2 (the right side of FIG. 2), and the paper feed rollers 103 that are arranged substantially directly above the trays 101 and 102. 104, the sheet feeding guides 4A and 4B provided with the sheet feeding roller 106 arranged near the sheet feeding rollers 103 and 104, and provided near the sheet feeding guide 4b, and rotated near the outer peripheral surface. The contact roller 7, the gripper 6, the transfer material separating charger 12, and the separation claw 14 are arranged from the upstream side to the downstream side in the direction, and the transfer charger 9 and the transfer material separating side are provided on the inner peripheral side. A charger 13 is provided. The transfer drum 8 rotatable in the direction of the arrow in FIG. 2 and the conveyor belt means 1 provided in the vicinity of the separation 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 detachable and a fixing device 16 that is adjacent thereto.

The latent image forming section II has an outer peripheral surface abutting on the outer peripheral surface of the transfer drum 8 and an image carrier (ie, the photosensitive drum 2) rotatable in the direction of the arrow in FIG. , A charge removing charger 10, a cleaning unit 11, a primary charger 3, and the photoconductor, which are arranged near the outer peripheral surface of the photoconductor drum 2 from the upstream side to the downstream side in the rotation direction of the photoconductor 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 member at a position which is mounted in the rotating body 4a and faces the outer peripheral surface of the photosensitive drum 2. A yellow developing device 4Y, a magenta developing device 4M, and a cyan developing device 4 configured to visualize (that is, develop) the electrostatic latent image formed on the outer peripheral surface of the drum 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. 2, 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. 4, 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 electrode facing the contact roller 7. The transfer drum 8 rotates in the direction of the arrow in FIG. 2 in synchronism with the photosensitive drum 2, and the visible image developed by the yellow developing device 4Y is transferred to the outer peripheral surface of the photosensitive drum 2 and the transfer drum 8.
The image is transferred by the transfer charger 9 at a portion in contact with the outer peripheral surface of. The transfer drum 8 continues to rotate,
Prepare for the transfer of the next color (magenta in FIG. 2).

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 carried out for cyan color and black color respectively, and when the transfer of four colors is completed, the multicolor image formed on the transfer material is charged by the chargers 12 and 13. The charge is removed, and the gripping of the transfer material by the gripper 6 is released. The transfer material is separated from the transfer drum 8 by the separation claws 14 and sent to the fixing device 16 by the conveyor belt 15 to be fixed by heat and pressure. The series of full-color print sequences is completed, and the required full-color print image is formed.

The fixing device 16 includes a heat fixing roller 161 and a pressure roller 162.

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

[0078]

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 .

Styrene 170 g 2-Ethylhexyl acrylate 30 g C.I. I. Pigment Blue 15: 3 10g

[0080]

[Chemical 4] X = OR (higher alkoxy group) (melting point 50 ° C., refractive index 1.481) Paraffin wax 30 g Di-tert-butylsalicylic acid metal compound 5 g

The above formulation was heated to 60 ° C. and 12,000 rpm using a TK 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 was cooled, hydrochloric acid was added to dissolve Ca ₃ (PO ₄ ) ₂ , and the mixture was filtered, washed with water and dried to obtain a polymerized toner. The particle size of the obtained toner was 8.5 μm in weight average diameter and had a sharp particle size distribution.

With respect to 100 parts by weight of the obtained toner, B
0.7 part by weight of hydrophobic silica having a specific surface area of 200 m ² / g according to the ET method was externally added. To 7 parts by weight of this toner, 93 parts by weight of an acrylic-coated ferrite carrier was mixed to obtain 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 in which a silicon roller having no oil coating function was used as a heat fixing roller. Fixing speed is 20mm /
It was set to sec.

The obtained fixed image was a transparent image having excellent fixability without offset. When actually projected by 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. .

C. I. Pig Y: 17 10g

[0089]

[Chemical 5] X = OCOR (higher fatty acid ester group) (melting point 70 ° C., refractive index 1.501)

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. 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 procedure of Example 1 was repeated, except that the paraffin wax was removed and the formulation of the polysiloxane compound was changed as follows, to obtain a polymerized toner having a weight average diameter of 8.3 μm. It was

[0092]

[Chemical 6] (Melting point 45 ° C, refractive index 1.448)

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. When actually projected by an overhead projector, the image was excellent in transparency (the results are shown in Table 1).

Comparative Example 1 When the unfixed image obtained in Example 1 was fixed by an external fixing device having a fluorine-based heat fixing roller, a transparency image excellent in light transmittance was obtained, but Since image unevenness occurs, the image quality is slightly inferior to that of the first embodiment.

Comparative Example 2 A toner having a weight average diameter of 7.4 μm was obtained by using the same procedure as in Example 1 except that the polysiloxane compound was omitted. The toner thus obtained was treated in the same manner as in Example 1 to form an unfixed image, and then a transparent image was formed using an external fixing device having a fluorine-based heat fixing roller. Since the obtained image was a crystal of paraffin wax, unevenness occurred and the light transmittance was slightly inferior to that of Example 1.

[0096]

[Table 1]

[0097]

According to the present invention, it is possible to obtain a fixed image which can be fixed at a low temperature, has a wide fixing temperature range, and has excellent fixability without applying oil. Further, since the transparency is not impaired, it is suitable for fixing to a transparency sheet.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a fixing device capable of fixing a full-color image according to the present invention.

FIG. 1 is a schematic sectional view of an electrophotographic apparatus capable of forming a full-color image according to the present invention.

[Explanation of symbols]

 2 Photoconductor drum 8 Transfer drum 16 Fixing device 21 Heater 22 Web 23 Offset prevention layer 24 Elastic layer 25 Core bar

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 31, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a fixing device capable of fixing a full-color image according to the present invention.

FIG. 2 is a schematic sectional view of an electrophotographic apparatus capable of forming a full-color image according to the present invention.

[Explanation of Codes] 2 Photoconductor drum 8 Transfer drum 16 Fixing device 21 Heater 22 Web 23 Offset prevention layer 24 Elastic layer 25 Core bar

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kazuya Kasuya Invaluable 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuyuki Miyano 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (2)

[Claims] 1. A fixing roller having an elastic layer on a roller base material, and further having an offset prevention layer formed of a silicone resin on the elastic layer, and fixing an unfixed toner image on a recording material. In the toner used in the heat fixing method, the toner is represented by the following general formula (1) or (2): [In the formula, X is -R ₁ (R ₂ O) _j (R ₃ O) _k R ₄
(R _{1 to} R ₄ are alkyl groups, j and k are natural numbers), a polyether group represented by —O—COR ₅ (R ₅ is an alkyl group), or —OR ₆ (R ₆ is an alkyl group) Group) is an alkoxy group. m and n are natural numbers. ] A toner for heat fixing, which is a suspension polymerization color toner containing a polysiloxane compound having a melting point of 30 to 150 ° C. and a refractive index of 1.30 to 1.90. 2. A fixing roller having an elastic layer on a roller base material and further having an offset prevention layer on the elastic layer,
In the heat fixing method for fixing an unfixed toner image on a recording material, the toner is represented by the following general formula (1) or (2): [In the formula, X is -R ₁ (R ₂ O) _j (R ₃ O) _k R ₄
(R _{1 to} R ₄ are alkyl groups, j and k are natural numbers), a polyether group represented by —O—COR ₅ (R ₅ is an alkyl group), or —OR ₆ (R ₆ is an alkyl group) Group) is an alkoxy group. m and n are natural numbers. ] A suspension polymerization method color toner containing a polysiloxane compound having a melting point of 30 to 150 ° C and a refractive index of 1.30 to 1.90 is used, and the offset prevention layer is formed of a silicone resin. A heat fixing method, characterized in that