JP3507312B2 - Magnetic toner and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic toner used in a recording method using an electrophotographic method, an electrostatic recording method, a magnetic recording method and the like, and a method for producing the same. Specifically, according to the present invention, after a toner image is previously formed on an electrostatic latent image carrier, it is transferred onto a transfer material to form an image, and the toner image is fixed on the transfer material by heat / pressure to form a final image. obtain,
The present invention relates to a magnetic toner used in copiers, printers and fax machines, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, a number of electrophotographic methods are known, but generally, a photoconductive material is used to form an electric latent image on a photoconductor by various means, and then the electrophotographic image is formed. The latent image is developed with toner to make it a visible image. If necessary, the toner image is transferred to a transfer material such as paper, and then the toner image is fixed on the transfer material by heat or pressure to obtain a copy. It is a thing.

In recent years, there is an increasing demand for colorization of copying machines, printers and fax machines using electrophotography. Generally, as a color toner, a non-magnetic toner is used because it is difficult to use a magnetic toner containing a magnetic material due to its tint. When a magnetic toner is used as the black toner and a non-magnetic toner is used as the color toner, the charge amount of the magnetic toner is lower than that of the non-magnetic toner, and when the toner image is transferred to the transfer material, the transferability of the magnetic toner is non-magnetic. It tended to be inferior to toner.

As a means for increasing the charge amount of toner to improve transferability, Japanese Patent Application Laid-Open No. 61-279864 proposes a toner in which shape factors SF-1 and SF-2 are specified. However, there is no description regarding transfer in this publication, and as a result of carrying out Examples, transfer efficiency is low and further improvement is required.

Further, JP-A-63-235953 and JP-A-2-167566 propose a magnetic toner spherically shaped by a mechanical impact force. However, the transfer efficiency is still insufficient and further improvement is needed.

Further, in recent years, there has been a demand for low-temperature fixing of toner, and further diversification of paper materials has made it possible for copying machines, printers, and fax machines using electrophotography to be more conventional than before. Even when a thick paper or an OHT film is used at a low fixing temperature, offset does not occur in a low temperature region, and it is now required to maintain a sufficient fixing property.

Addition of wax can be mentioned as a means for providing good fixing strength without causing the toner offset phenomenon. However, it is difficult to disperse the wax because the compatibility with the binder resin is not so good originally and the viscosity of the wax is very low during kneading, so that the kneading device is hardly sheared. In addition, Japanese Patent Publication No. 57-52574 proposes to use low molecular weight polyethylene having a weight average molecular weight Mw of about 1,000 to 10,000 as a toner component. However, the above-mentioned recent low-temperature fixing and diversification of paper materials have not been sufficiently dealt with.

In recent years, from the viewpoint of environmental protection, primary charging using a corona discharge which has been conventionally used and primary charging using an image carrier contact member from the transfer process,
The transfer process is becoming mainstream.

For example, JP-A-63-149669 and JP-A-2-123385 have been proposed. These are related to the contact charging method and the contact transfer method, but a conductive elastic roller is brought into contact with the electrostatic latent image carrier,
The electrostatic latent image bearing member is uniformly charged while applying a voltage to the conductive roller, and then a toner image is obtained by exposure and development steps, and then a voltage is applied to the electrostatic latent image bearing member. While the conductive material is being pressed, the transfer material is allowed to pass therethrough to transfer the toner image on the electrostatic latent image carrier to the transfer material, and then a fixing step is performed to obtain a copied image.

However, in such a roller transfer system which does not use corona discharge, the transfer member is brought into contact with the photoconductor through the transfer member during transfer, so that the toner image formed on the photoconductor is transferred to the transfer material. When the toner image is transferred to the toner image, the toner image is brought into pressure contact with the toner image, which causes a problem of partial transfer failure, which is so-called transfer void.

Further, as the diameter of the toner becomes smaller, the adhesion force of the toner particles (image force, van der Waals force, etc.) to the photoconductor becomes larger than the Coulomb force applied to the toner particles by the transfer. As a result, the transfer residual toner tends to increase.

Further, in the roller charging system, the physical and chemical action on the surface of the electrostatic latent image bearing member due to the discharge generated between the charging roller and the electrostatic latent image bearing member is larger than that in the corona charging system. In particular, in the combination with the organic photoconductor / blade cleaning, the surface of the image bearing member was easily worn and there was a problem in life (direct charging / organic photoconductor / one-component magnetic developing method / contact transfer / blade cleaning , Which is the mainstream method for copiers, printers, facsimiles, etc., in fields where low cost, small size and light weight are required, as it is easy to reduce the cost and size and weight of the image forming apparatus.)

Therefore, it has been required that the toner and the image bearing member used in such an image forming method have excellent releasability.

[0014]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a magnetic toner and a toner manufacturing method which solves the above problems of the prior art.

That is, an object of the present invention is to provide a magnetic toner having high charging performance and high transfer performance, and a method for producing the toner.

A further object of the present invention is to provide a magnetic toner which does not cause offset in a low temperature region and has a sufficient fixing strength, and a method for producing the toner.

A further object of the present invention is to provide a magnetic toner having a high release performance by uniformly dispersing a wax in a binder resin and a method for producing the toner.

[0018]

Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned objects, the present inventors have found that, in the step of melt-kneading, the temperature set in the barrel section of the kneading section and the outlet of the melt-kneader are set. It has been found that the above objects can be achieved by defining the temperature, the viscosity of the wax at that temperature, and the various properties of the toner and the wax.

That is, according to the present invention, toner mother particles produced by melt-kneading at least a binder resin, a magnetic material and a wax using a screw extrusion kneader having a feed screw part and at least one kneading part. and the magnetic toner having an inorganic fine powder, when the temperature of the kneaded material in the melting kneader outlet was T1 (° C.),
The viscosity of the wax at T1 (° C) is 12 to 30 mP
a · s (preferably 15 to 25 mPa · s) ,
If the THF insoluble content of the binder resin of the magnetic toner is 5% by weight or less
Yes, the binder resin is a THF-soluble component GPC molecular weight distribution
, The content (M1) of the component having a molecular weight of less than 50,000 is 4
0 to 70%, containing components with a molecular weight of 50,000 to 500,000
The amount (M2) is 20-45%, and the molecular weight exceeds 500,000.
Content of the component (M3) is 2 to 25%, and M1
A magnetic toner and a method of manufacturing the same are characterized in that ≧ M2 ≧ M3 .

The present inventors have earnestly studied a method for uniformly dispersing a magnetic substance and a wax in a binder resin. As a result, the temperature of the kneaded material at the melt kneader discharge port was set to T1.
(° C), the viscosity of the wax is 12 to 30 mP
It has been found that when T1 (° C.) is set so as to be a · s and melt-kneading is performed, the wax is appropriately dispersed on the surface of the toner particles. This dispersed state affects the surface property of the toner of the present invention, and the charging performance of the toner,
It is presumed that it has an effect on the transfer performance, the fixing performance in the low temperature fixing area and the releasing performance.

Further, │T0-T2 where T0 (° C) is the barrel temperature set at the kneading part on the rearmost side of the screw of the screw extrusion kneader and T2 (° C) is the endothermic main peak of the DSC of the wax. | ≦ 30
(C) and having one or more T2 (C) within the range of 60 to 120 ° C., it is more effective in the proper wax dispersion state of the present invention in the melt-kneading step. I understand.

A value obtained by subtracting the temperature T2 (° C) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C) of the kneaded material at the outlet of the melt-kneader, T1 (° C) -T2
It has been found that when the (° C) is set within the range of 10 to 60 ° C, more preferably 20 to 50 ° C, the appropriate wax dispersion state of the present invention is further improved.

Further, the shape factor S measured by the image analyzer is
The value of F-1 is 110 <SF-1 ≦ 180, the value of the shape factor SF-2 is 110 <SF-2 ≦ 140, and S
When the toner is manufactured such that the ratio B / A of the value B obtained by subtracting 100 from the value of F-2 and the value A obtained by subtracting 100 from the value of SF-1 is 1.0 or less, the unevenness is small. It has been found that the influence of the wax exposed on the surface of the toner particles is increased due to the shape, which has an effect on the charging performance and transfer performance of the toner.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention includes at least a binder resin,
In a magnetic toner having toner mother particles and inorganic fine powder produced by melt-kneading a magnetic substance and wax using a screw extrusion kneader having a feed screw part and at least one kneading part, the melt-kneader discharge When the temperature of the kneaded material at the outlet is T1 (° C), T1
The viscosity of the wax at (° C.) is 12 to 30 mPa ·
s, more preferably 15 to 25 mPa · s. If the viscosity is less than 12 mPa · s, the storability of the toner is significantly reduced, which is not preferable. When the viscosity exceeds 30 mPa · s, it is difficult to obtain a proper wax dispersion state.

According to the present invention, from the viewpoint that when the toner is formed into a toner, the wax is appropriately dispersed on the toner surface, the barrel portion set temperature in the kneading portion on the tail end side of the screw of the screw extrusion kneader is set to T0.
(° C), where T2 (° C) is the temperature of the DSC endothermic main peak of the wax, | T0-T2 | ≦ 30 (° C)
Within the range of. Within this range, it is considered that the wax within the binder resin can efficiently penetrate and disperse easily.

In the present invention, from the viewpoint of improving the releasability from the fixing member and the fixing property in the low temperature fixing region,
Temperature T2 (° C) at the DSC endothermic main peak of wax
It is preferable to have at least one at 120 ° C. or lower (more preferably 110 ° C. or lower). If the endothermic main peak temperature T2 is less than 120 ° C., it is difficult to obtain a proper wax dispersion state.

Main DSC endothermic temperature T of wax
It is preferable that 2 (° C.) does not exist at 60 ° C. or lower (more preferably 70 ° C. or lower). When the wax has a DSC endothermic main peak temperature T2 of 60 ° C. or lower, the developing sleeve is significantly contaminated and the image density is lowered. In addition, the storability also deteriorates.

A value obtained by subtracting the temperature T2 (° C.) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C.) of the kneaded material at the outlet of the melt kneader, Tl (° C.)-T2
(C) is preferably in the range of 10 to 60 ° C, more preferably 20 to 50 ° C. When T1-T2 is lower than 10 ° C, the dispersibility of the binder resin and other materials is not improved.
If T1-T2 exceeds 60 ° C., reaggregation of the wax will occur.

The wax is preferably any one of a polyolefin wax and its derivative, a hydrocarbon wax and its derivative synthesized by the Fischer-Tropsch method, a petroleum wax and its derivative, a higher aliphatic alcohol and its derivative. . When these waxes are used, it is easy to obtain an appropriate wax dispersion state in the melt-kneading step.

The ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of these waxes is 1.0 ≦ Mw / M.
It is preferable that n ≦ 2.0. By including the wax having a considerably sharp molecular weight distribution in the toner, it is easy to obtain an appropriate wax dispersion state in the melt-kneading step in the production of the toner.

As the resin used in the present invention, the binder resin has a THF insoluble content of 5% by weight or less, and the binder resin is T
In the GPC molecular weight distribution of the HF soluble component, the molecular weight was 5
The content (M1) of less than 10,000 components is 40 to 70%,
The content (M2) of components having a molecular weight of 50,000 to 500,000 is 20 to
45%, the content of components with a molecular weight of more than 500,000 (M
It is desirable that 3) is 2 to 25% and that M1 ≧ M2 ≧ M3.

Further, the toner of the present invention has a viscoelasticity tan δ value C at 100 ° C. and a viscoelasticity t at 150 ° C.
The value of the ratio D / C to the value D of an δ is D / C ≧ 1, and 1
It is desirable that the viscoelasticity tan δ value E in the range of 50 ° C. to 190 ° C. is 3.0 ≧ E ≧ 0.5. D / C
When the value and E value satisfy the above ranges, high charging performance, high transfer performance and a wide fixing temperature range can be obtained, and at the same time, durability stability can be satisfied.

When the D / C value is less than 1, or when the E value is more than 3.0 or less than 0.5, it is difficult to achieve both high transferability and durability stability.

The type of the binder resin used in the present invention is, for example, a homopolymer of styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene or the like, or a substitution product thereof; styrene-p-chlorostyrene copolymerization. Coal, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene- Acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile- Styrene-based copolymers such as indene copolymers Combined; polyvinyl chloride, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, silicone resin, polyester resin, polyurethane, polyamide resin, furan resin, epoxy resin, xylene resin , Polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin and the like can be used. A crosslinked styrene resin is also a preferable binder resin.

Examples of the comonomer for the styrene monomer of the styrene type copolymer include acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate,
Didecyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, octyl methacrylate, octyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, etc. A monocarboxylic acid having a heavy bond or a substituted product thereof;
For example, a dicarboxylic acid having a double bond such as maleic acid, butyl maleate, methyl maleate, dimethyl maleate, and the like; and substituted compounds thereof; for example, vinyl chloride,
Vinyl esters such as vinyl acetate, vinyl benzoate, etc., ethylene-based olefins such as ethylene, propylene, butylene, etc .; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, etc .;
For example, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether and the like; and vinyl monomers such as are used alone or in combination.

As the cross-linking agent, a compound having two or more polymerizable double bonds is mainly used. For example, an aromatic divinyl compound such as divinylbenzene, divinylnaphthalene, etc .; for example, ethylene glycol diacrylate. , Ethylene glycol dimethacrylate,
Carboxylic acid esters having two double bonds such as 1,3-butanediol dimethacrylate; divinyl compounds such as divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfone; and compounds having three or more vinyl groups Can be used alone or as a mixture.

As the binder resin for toner used for pressure fixing, low molecular weight polyethylene, low molecular weight polypropylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid ester copolymer, higher fatty acid, polyamide Resin and polyester resin can be used. These are preferably used alone or in combination.

In the toner of the present invention, a charge control agent can be used by being mixed with toner particles (internal addition) or mixed with toner particles (external addition), which is preferable. The charge control agent makes it possible to control the optimum charge amount according to the developing system, and particularly in the present invention, the balance between the particle size distribution and the charge amount can be further stabilized.

To control the toner to be negatively charged,
For example, there are the following substances.

Organic metal complexes and chelate compounds are effective, for example, monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid metal complexes. Other examples include aromatic hydroxycarboxylic acids, aromatic mono- and polycarboxylic acids and their metal salts, anhydrides, esters, and phenol derivatives such as bisphenol.

Further, the following substances are exemplified as those which are controlled to be positively charged.

Modified products of nigrosine and fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate, tetrabutylammonium tetrafluoroborate and phosphonium salts which are analogs thereof. Onium salts and lake pigments thereof, triphenylmethane dyes and lake pigments thereof (as a laker, phosphotungstic acid, phosphomolybdic acid, phosphotungstic molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide) Compounds, ferrocyanides, etc.), metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide, dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate, dicyclohexyl Diorgano tin borate such as Suzuboreto; can be used in combination singly or two or more kinds.

The charge control agents described above are preferably used in the form of fine particles, and in this case, the number average particle diameter of these charge control agents is preferably 4 μm or less, more preferably 3 μm or less. When these charge control agents are internally added to the developer, it is preferably used in an amount of 0.1 to 20 parts by weight, particularly 0.2 to 10 parts by weight, based on 100 parts by weight of the binder resin.

As the coloring material that can be further added to the developer of the present invention, conventionally known carbon black, copper-phthalocyanine and the like can be used.

As the colorant used in the present invention, carbon black, a magnetic substance, or a yellow / magenta / cyan colorant shown below, which is toned black, is used.

As the yellow colorant, condensed azo compounds, isoindolinone compounds, anthraquinone compounds,
Compounds represented by azo metal complexes, methine compounds and allylamide compounds are used. Specifically, C.I. I. Pigment Yellow 12, 13, 14, 15, 17, 6
2, 74, 83, 93, 94, 95, 109, 110,
111, 128, 129, 147, 168, etc. are used suitably.

As the magenta colorant, a condensed azo compound, a diketopyrrolopyrrole compound, an anthraquinone, a quinacridone compound, a basic dye lake compound, a naphthol compound, a benzimidazolone compound, a thioindigo compound and a perylene compound are used. Specifically, C.I.
I. Pigment Red 2, 3, 5, 6, 7, 23, 4
8: 2, 48: 3, 48: 4, 57: 1, 81: 1, 1
44, 146, 166, 169, 177, 184, 18
5,202,206,220,221,254 are particularly preferred.

As the cyan colorant used in the present invention, copper phthalocyanine compounds and their derivatives, anthraquinone compounds, basic dye lake compounds and the like can be used.
Specifically, C.I. I. Pigment Blue 1, 7, 15,
15: 1, 15: 2, 15: 3, 15: 4, 60, 6
2, 66 and the like can be used particularly preferably.

These colorants can be used alone or in a mixture, and can be used in the form of a solid solution. The colorant of the present invention is selected in terms of hue angle, saturation, lightness, weather resistance, OHP transparency, and dispersibility in the toner. The colorant is added in an amount of 1 to 20 parts by weight based on 100 parts by weight of the resin.

The toner of the present invention is preferably used by adding 30 to 200 parts by weight of the magnetic material to 100 parts by weight of the resin.

Examples of magnetic materials include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum and silicon. Of these, those containing iron oxide as a main component, such as ferrosoferric oxide and γ-iron oxide, are preferable. Further, from the viewpoint of controlling the toner chargeability, other metal elements such as silicon element or aluminum element may be contained. The BET specific surface area of these magnetic particles by the nitrogen adsorption method is preferably ² to 30 m ² / g, particularly 3
A magnetic powder having a hardness of ˜28 m ² / g and a Mohs hardness of 5 to 7 is preferable.

The shape of the magnetic material is octahedron, hexahedron,
There are spheres, needles, scales, and the like, but those having less anisotropy such as octahedron, hexahedron, sphere, and amorphous are preferable for increasing the image density. The average particle size of the magnetic substance is 0.05 to
1.0 μm is preferable, and 0.1 to 0.
6 μm, and more preferably 0.1 to 0.4 μm.

The amount of magnetic material is 3 with respect to 100 parts by weight of the binder resin.
0 to 200 parts by weight, preferably 40 to 200 parts by weight, and more preferably 50 to 150 parts by weight. If the amount is less than 30 parts by weight, in a developing device that uses magnetic force to convey toner,
The transportability was insufficient and the developer layer on the developer carrying member was uneven, which tended to cause image unevenness, and the image density tended to be lowered due to an increase in developer tribo.
On the other hand, if the amount exceeds 200 parts by weight, the fixing property tends to be problematic.

As the inorganic fine powder contained in the toner of the present invention, known ones are used, but silica, alumina, titania, or a mixture thereof is used for the purpose of improving charge stability, developability, fluidity and storage stability. It is preferably selected from oxides. Furthermore, silica is more preferable. For example, as the silica, both a so-called dry method produced by vapor phase oxidation of a silicon halide or an alkoxide or a dry silica called fumed silica, and a so-called wet silica produced from alkoxide water glass or the like can be used. However, there are few silanol groups on the surface and inside the silica fine powder, and Na ₂ O, SO ₃ ^2-
Preference is given to dry silica having less production residue such as. Further, in the case of dry silica, it is possible to obtain a composite fine powder of silica and another metal oxide by using another metal halogen compound such as aluminum chloride and titanium chloride together with the silicon halogen compound in the manufacturing process. , Including those.

The inorganic fine powder used in the present invention is BET.
The specific surface area by measuring nitrogen adsorption in law 30 m ² / g or more, especially given the 50 to 400 m ² / g good results in the range of fine silica powder of 0.1 to 8 weight relative to 100 parts by weight of the toner Parts, preferably 0.5 to 5 parts by weight, more preferably more than 1.0 and up to 3.0 parts by weight.

The inorganic fine powder used in the present invention is
Silicone varnishes, various modified silicone varnishes, silicone oils, various modified silicone oils, silane coupling agents, silane coupling agents having functional groups, other organic silicon compounds, organics for the purpose of hydrophobicization, control of charging properties, etc. It is also possible and preferable to treat with a treating agent such as a titanium compound or in combination with various treating agents.

In order to maintain a high charge amount, achieve a low consumption amount and a high transfer rate, it is more preferable that the inorganic fine powder is treated with at least silicone oil.

The toner of the present invention has a shape factor SF-1 of 110 <SF-, which is measured by an image analyzer of toner particles.
1 ≦ 180 (more preferably 120 <SF-1 ≦ 16
0) and the value of the shape factor SF-2 is 110 <SF-2.
≤140 (more preferably 115 <SF-1≤140)
And SF− is obtained by subtracting 100 from SF−2 and SF−
The ratio B / A with the value A obtained by subtracting 100 from the value of 1 is preferably 1.0 or less (more preferably 0.2 to 0.95).

When SF-1 is 110 or less, and S
When F-2 is 110 or less, the ratio B / A is 1.0.
If it exceeds, it becomes difficult to clean the transfer residual toner remaining on the latent image carrier, and cleaning failure tends to occur.

When SF-1 exceeds 180, and SF
When -2 exceeds 140, high transfer efficiency cannot be obtained.

The toner of the present invention may further contain other additives such as Teflon powder within a range that does not have a substantial adverse effect.
Lubricant powder such as zinc stearate powder and polyvinylidene fluoride powder, abrasive such as cerium oxide powder, silicon carbide powder, strontium titanate powder, or fluidity imparting agent such as titanium oxide powder and aluminum oxide powder, anti-caking A small amount of an agent or a conductivity imparting agent such as carbon black powder, zinc oxide powder, tin oxide powder, or organic fine particles and inorganic fine particles having opposite polarities can be used as a developing property improver.

A known method is used for producing the toner according to the present invention. For example, a binder resin, a wax,
A metal salt or a metal complex, a pigment or dye as a colorant, a magnetic material, a charge control agent if necessary, and other additives are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill, and then the feed screw portion After melting and kneading with a screw extrusion kneader having at least one kneading part to make the resins compatible with each other, disperse or dissolve the metal compound, pigment, dye, and magnetic substance, cool and solidify, and after crushing A method is preferably used, in which classification and surface treatment are performed as necessary to obtain toner particles, and if necessary, inorganic fine powder and the like are added and mixed for production.

The toner of the present invention may be pulverized (classified if necessary) by a method using a known mechanical crushing device such as a mechanical impact type or a jet type, but a process of additionally applying a mechanical impact may be performed. Is preferable, and it is preferably used because the latitude of the transfer condition is widened.

Further, a finely pulverized (classified as required) toner particles may be dispersed in hot water such as a hot water bath method or a method of passing through a hot air stream, but the toner charge amount is low. The method of applying the treatment by the mechanical impact force is the most preferable from the viewpoints of the blunt transfer characteristic and other image characteristics and the productivity.

As the treatment for applying mechanical impact force, for example, a method using a mechanical impact type crusher such as a Kryptron system manufactured by Kawasaki Heavy Industries Ltd. or a turbo mill manufactured by Turbo Kogyo Co., Ltd.,
Also, like the devices such as Hosokawa Micron's Mechanofusion System and Nara Machinery's Hybridization System, the toner is pressed against the inside of the casing by the centrifugal force by the blades rotating at high speed,
A method in which a mechanical impact force is applied to the toner by a force such as a friction force can be used.

When the process of applying a mechanical impact force is carried out after the finely pulverizing step of the toner or after the further classifying step, the effects of the charging property and the transfer property of the toner are further enhanced, which is particularly preferable.

Either the classification or the surface treatment may be performed first. In the classification step, it is preferable to use a multi-division classifier in terms of production efficiency.

In the mechanical impact method, a thermomechanical impact in which the treatment temperature is a temperature (Tg ± 10 ° C.) around the glass transition point Tg of the toner particles is preferable from the viewpoint of preventing aggregation and productivity. More preferably, the glass transition point Tg ± of the toner is
Performing at a temperature in the range of 5 ° C. is particularly effective for improving transfer efficiency.

The weight average particle diameter of the toner is 8.0 μm.
The following is preferable. When the weight average particle diameter of the toner is 8.0 μm or less, the effect of transfer performance is further enhanced. The reason is that the weight average particle diameter of the toner is 8.
It is considered that when it is 0 μm or less, the charge amount of the toner on the electrostatic latent image bearing member or the intermediate transfer member before transfer is further increased.

The viscosity is measured using an E-type rotational viscometer. As a viscometer, for example, VT-500 (HAAK
(Manufactured by Company E) can be used. In the examples, VT-50
0 was used and the measured temperature was adjusted by an oil bath with a temperature regulator. PKI, 0.5 ° was used for the sensor, and the share rate was measured at 6000 s ⁻¹ .

Glass transition point Tg of the toner according to the present invention
For example, DSC- manufactured by Perkin Elmer Co., Ltd.
The measurement is performed with a highly accurate internal heat input compensation type differential scanning calorimeter such as 7. The measuring method is ASTM D3418-8.
Perform according to 2. In the present invention, the sample is heated once to take a previous history, then rapidly cooled, and then again at a temperature rate of 10 ° C./m.
In, a DSC curve measured when the temperature is raised in the range of 0 to 200 ° C. is used.

The molecular weight is measured by GPC (gel permeation chromatography). Concrete GP
As a method of measuring C, a sample obtained by previously extracting the toner with a Soxhlet extractor for 20 hours using a THF (tetrahydrofuran) solvent was used, and the column configuration was A-801, 802, 803, 804, 805, 80 manufactured by Showa Denko.
6,807 can be connected and the molecular weight distribution can be measured using the calibration curve of standard polystyrene resin.

The viscoelasticity tan δ value is measured by the viscoelasticity measuring device RD.
A-II type (manufactured by Rheometrics) is used, a parallel plate having a diameter of 25 mm is used as a measuring jig, a measuring frequency is 6.28 rad / sec, and a measuring temperature is increased from 100 ° C. to 200 ° C. at 1 ° C./min. It was warmed and measured.

In the present invention, SF-indicating the shape factor
1 and SF-2 are, for example, Hitachi FE-SEM
(S-800) is used to randomly sample 100 toner images of 2 μm or more magnified 1000 times, and the image information is introduced into an image analysis device (Luzex III) manufactured by Nicolet Co., Ltd. through an interface. The value obtained by performing the analysis and calculating from the following equation is used as the shape factor SF-1, S
It is defined as F-2.

[0075]

[Equation 1] (In the formula, MXLNG is the absolute maximum length of the particle, PERIME
Is the perimeter of the particle, AREA is the projected area of the particle)

As the weight average particle diameter of the toner of the present invention, Coulter Counter TA-II type or Coulter Multisizer (manufactured by Coulter Co.) is used. As the electrolytic solution, a 1% NaCl aqueous solution is prepared using first grade sodium chloride. For example, ISOTON R-II (manufactured by Coulter Scientific Japan) can be used. As a measuring method, 0.1 to 5 ml of a surfactant (preferably alkylbenzene sulfonate) as a dispersant is added to 100 to 150 ml of the electrolytic aqueous solution, and 2 to 2 of measurement samples are further added.
Add 0 mg. The electrolytic solution in which the sample is suspended is dispersed by an ultrasonic disperser for about 1 to 3 minutes, and the volume distribution and the number distribution of the toner of 2 μm or more are measured by measuring the volume and the number of the toner of 2 μm or more using the 100 μm aperture as the aperture by the above apparatus. Was calculated. Then, the volume-based weight average particle diameter (D4) determined from the volume distribution according to the present invention was determined.

[0077]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto.

[0078]   <Example 1> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.18 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 107 ° C) 4 parts by weight

First, the above materials were mixed with a Henschel mixer (F
After thoroughly mixing with M-75 type, manufactured by Mitsui Miike Kakoki Co., Ltd., the barrel part set temperature in the kneading part at the rear end of the screw of the screw extrusion kneader was set to T0 (° C).
= 90 ° C., melt-kneader discharge port temperature T1 = 145 ° C., twin-screw kneader (PCM-30 type, Ikegai Iron Works Co., Ltd.)
Manufactured). The obtained kneaded product was cooled and coarsely pulverized with a hammer mill to 1 mm or less to obtain a toner pulverized product. Next, the coarsely pulverized product was finely pulverized by a collision type air flow pulverizer to obtain a pulverized raw material. Next, the obtained pulverized raw material was introduced into a multi-division classifier elbow jet classifier (manufactured by Nittetsu Mining Co., Ltd.) to obtain toner particles.

Using a surface reforming device of the type which applies a mechanical impact force to the toner particles by rotating a rotor, 1600r
The surface treatment was performed by a batch method for 3 minutes at pm (peripheral speed 80 m / sec). The internal fluid temperature during treatment reached a maximum of 55 ° C due to the heat generated by the impact of the rotor and particles.

To 100 parts by weight of the toner particles, 2.0% by weight of dry silica having a primary particle diameter of 12 nm was added and well mixed with a Henschel mixer to obtain a toner A. The weight average diameter of the obtained toner is 5.69 μm, and the charge amount is −45.
(MC / kg).

The method for measuring the charge amount (two-component tribo value) of the toner according to the present invention by the two-component method will be described below.

In an environment of 23 ° C. and relative humidity of 60%, EFV200 / 300 (manufactured by Powder Tech Co., Ltd.) was used as a carrier, and a mixture of 9.5 g of carrier and 0.5 g of toner was added to a polyethylene bottle having a capacity of 50 to 100 ml. Shake by hand 50 times. Then, as a suction port at the bottom, 500
1.0 to 1.2 g of the mixture is put in a metal measuring container having a mesh screen, and a metal lid is put on the container. At this time, the total weight of the measurement container is weighed and set to W1g. next,
In the suction device (at least the part in contact with the measurement container is an insulator), suction is made from the lower part of the suction port and the air volume control valve is adjusted to adjust the pressure of the vacuum gauge to 2450 Pa (250 mmAq). In this state, the toner is sucked and removed through the 500 mesh screen for 1 minute. The potential of the electrometer at this time is V (volt). Here, a capacitor is connected to the ammeter and the capacity is C (μF). Further, the weight of the entire measuring machine after suction is weighed and is W2 (g). The triboelectric charge amount (mC / kg) of this toner is calculated by the following formula.

[0084] Triboelectric charge amount (mC / kg) = CV / (W1-W2)

The image forming apparatus shown in FIGS. 1 and 2 was used. An organic photoconductor (OPC) drum is used as the electrostatic latent image carrier 100, and the dark portion potential Vd = −7.
00V and bright part potential VL = -210V. The gap between the photosensitive drum 100 and the developing sleeve 102 is set to 300 μm, and the toner carrier has the following layer thickness of about 7 μm and J
Using a developing sleeve in which a resin layer having an IS center line average roughness (Ra) of 0.8 μm is formed on an aluminum cylinder having a mirror surface and a diameter of 16φ, a developing magnetic pole of 95 mT (950
Gauss), the thickness of the toner regulating member 103 is 1.0 m
Urethane rubber blade with a free length of 10 mm
They were brought into contact with each other with a linear pressure of 7 N / m (15 g / cm).

Next, as a developing bias, a DC bias component Vdc = -500V and an AC bias component V to be superimposed.
pp = 1200V and f = 2000Hz were used. Further, the peripheral speed of the developing sleeve 102 is the peripheral speed of the photosensitive member (48 mm
/ Sec) forward direction (reverse direction as rotation direction)
And a speed of 150% (72 mm / sec).

The transfer roller 114 (made of ethylene-propylene rubber in which conductive carbon is dispersed, volume resistance value of conductive elastic layer 10 ⁸ Ωcm, surface rubber hardness 24 °, diameter 20 mm, contact pressure 49 N / m (50 g / Cm)) at a constant velocity with respect to the peripheral velocity of the photoconductor (48 mm / sec), +2000 V is applied as a transfer bias, magnetic toner A is used as toner, and an image is formed at 23 ° C. and 65% RH environment. Was done. As the transfer paper, 75 g / m ² paper was used.

The transferability was evaluated by a numerical value obtained by tapping the transfer toner on the solid black photoconductor with a Mylar tape and stripping it off, and subtracting the Macbeth density of the one with the tape alone from the Macbeth density of the one with the tape. .

The fixability was evaluated using a fixing unit of LBP-930 manufactured by Canon Inc. The transfer paper was 90 g / m ² , paper feed rate was 106 mm / sec, load was 17 kg, nip width was 4 mm, and fixing temperature was 150 ° C. The occurrence of offset after fixing was visually evaluated (3 grades of ○, △, and ×), and the fixing rate was rubbed 5 times reciprocally with sillbon paper loaded with 50 g / cm ² before and after rubbing. From the image density reduction rate, the fixability was judged (3 levels of ◯, Δ, and x).

At this time, the transfer efficiency from the photosensitive member to the transfer material was as high as 95%, showing high transfer efficiency, no offset occurred at low temperature fixing, and the fixing strength was sufficient.

The durability test is conducted by Canon LBP-930.
Was used to carry out an endurance test of 15,000 sheets.
As a result, there were no voids in the transfer of characters or lines, no sleeve ghosts, and no stains on the fixing roller from the initial stage to the endurance, which was a good result.

Barrel portion set temperature T0 at the time of manufacturing toner A
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

<Example 2> Kneader discharge port temperature T1 (° C)
= Toner B was obtained in the same manner as in Example 1 except that the temperature was changed to 130 ° C. The weight average diameter of the obtained toner is 6.39.
μm, the charge amount was −44 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material is as high as 95%, and no offset occurs during low temperature fixing,
The fixing strength was also sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner B
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

<Example 3> Barrel portion set temperature T0 (° C)
= 110 ° C, and the kneader discharge port temperature T1 (° C) = 160 ° C, except that the toner C was obtained in the same manner as in Example 1. The weight average particle diameter of the obtained toner was 7.56 μm, and the charging tatami was −43 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material is as high as 93%,
No offset occurred during low-temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner C
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0097]   <Example 4> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.22 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 111 ° C) 4 parts by weight

Toner D was obtained in the same manner as in Example 1 except that the above materials were used and the barrel temperature T0 (° C) was changed to 110 ° C. The weight average diameter of the obtained toner was 5.89 μm, and the charge amount was −46 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 95%, showing high transfer efficiency, no offset occurred at the time of low temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner D
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

<Embodiment 5> Barrel portion set temperature T0 (° C)
Toner E was obtained in the same manner as in Example 1 except that the kneader discharge port temperature T1 (° C.) = 160 ° C. was changed. The weight average diameter of the obtained toner was 6.88 μm, and the charge amount was −44 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material is as high as 92%,
No offset occurred during low-temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner E
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0102]   <Example 6> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.20 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 122 ° C) 4 parts by weight

Use of the above materials, barrel set temperature T0 (° C) = 150 ° C, kneader outlet temperature T1 (° C) =
Toner F was obtained in the same manner as in Example 1 except that the temperature was changed to 175 ° C. The weight average diameter of the obtained toner is 6.89.
μm, the charge amount was −43 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 90%, which showed high transfer efficiency, and no offset occurred during low temperature fixing. Although a slight decrease in fixing strength was observed, it was judged to be at a level where there was no practical problem. The endurance results were good, with no missing characters or lines during transfer or sleeve ghosts, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner F
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0105]   <Example 7> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 41,000, glass transition point Tg: 65 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.22 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 101 ° C) 4 parts by weight

Use of the above materials, barrel temperature T0 (° C) = 110 ° C, kneader outlet temperature T1 (° C) =
Rotate the rotor at 150 ° C, use a surface modification device of the type that gives a mechanical impact force, 1200 rpm (peripheral speed 60m
/ Sec), and toner G was obtained in the same manner as in Example 1 except that the surface treatment was performed by a batch method for 2 minutes. The obtained toner has a weight average diameter of 6.59 μm and a charge amount of −40 (mC
/ Kg). At this time, the transfer efficiency from the photosensitive member to the transfer material was as high as 90%, showing a high transfer efficiency, no offset occurred at the time of low temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner G
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0108]   <Example 8> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 42000, glass transition point Tg: 62 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.22 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 111 ° C) 4 parts by weight

Using the above materials, barrel temperature T0 (° C) = 130 ° C, kneader outlet temperature T1 (° C) =
Toner H was obtained in the same manner as in Example 1 except that the temperature was changed to 135 ° C. The weight average diameter of the obtained toner is 6.39μ.
m, the charge amount was -42 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 93%, showing high transfer efficiency, no offset occurred at the time of low temperature fixing, and the fixing strength was sufficient. Also, the endurance result is that there are no missing characters or sleeve ghosts in the transfer of letters or lines,
The fixing roller did not stain, which was a good result.

Barrel portion set temperature T0 at the time of manufacturing toner H
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0111]   <Example 9> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 41,000, glass transition point Tg: 65 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.22 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 76 ° C) 4 parts by weight

Using the above materials, barrel temperature T0 (° C) = 120 ° C, kneader outlet temperature T1 (° C) =
Use a surface modification device that rotates the rotor at 135 ° C to give a mechanical impact force, and 1200 rpm (peripheral speed 60 m
/ Sec), and toner I was obtained in the same manner as in Example 1 except that the surface treatment was carried out by a batch method for 3 minutes. The obtained toner has a weight average diameter of 7.05 μm and a charge amount of −40 (mC
/ Kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 91%, showing high transfer efficiency, no offset occurred during low temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner I
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0114]   <Example 10> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 42000, glass transition point Tg: 62 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.21 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 122 ° C) 4 parts by weight

Use of the above materials, barrel temperature T0 (° C) = 130 ° C, kneader outlet temperature T1 (° C) =
Toner J was obtained in the same manner as in Example 1 except that the temperature was changed to 150 ° C. The weight average diameter of the obtained toner is 6.89μ.
m, the charge amount was -44 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 92%, and the offset did not occur during the low temperature fixing. Although a slight decrease in fixing strength was observed, it was judged to be at a level where there was no practical problem. The endurance results were also good, with no missing prints or missing sleeve ghosts on the lines and lines, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner J
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

<Embodiment 11> Barrel portion set temperature T0
(° C) = 130 ° C, Kneader outlet temperature T1 (° C) = 13
Toner K was obtained in the same manner as in Example 10 except that the temperature was changed to 7 ° C. The weight average diameter of the obtained toner is 6.88μ.
m, the charge amount was -40 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as high as 92%, and the offset did not occur during the low temperature fixing. Although a slight decrease in fixing strength was observed, it was judged to be at a level where there was no practical problem. The endurance results were good, with no missing characters or lines during transfer or sleeve ghosts, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner K
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0119]   <Example 12> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 42000, glass transition point Tg: 62 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.21 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 107 ° C) 4 parts by weight

Toner L was obtained in the same manner as in Example 1 except that the above materials were used. The weight average diameter of the obtained toner was 7.59 μm, and the charge amount was −41 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material is 93%.
Shows high transfer efficiency, no offset occurs at low temperature fixing, and the fixing strength is sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller. After observing the developing sleeve,
A fused substance which is considered to be a toner was observed on the surface of the sleeve, but since it did not affect the image, it was judged to be a level without a problem.

Barrel portion set temperature T0 at the time of manufacturing toner L
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

<Embodiment 13> Kneader discharge port temperature T1
Example 1 except that (° C.) was changed to 137 ° C., and the surface modification of the method of giving a mechanical impact force was not performed.
A toner M was obtained in the same manner as in. The weight average diameter of the obtained toner is 6.59 μm, and the charge amount is −38 (mC / kg).
It was slightly lower. At this time, the transfer efficiency from the photosensitive member to the transfer material was 88%, which was a relatively high transfer efficiency, no offset occurred during low temperature fixing, and the fixing strength was sufficient. Also, the durability results were good, with no voids in the transfer of characters or lines, no sleeve ghost, and no fouling of the fixing roller.

Barrel portion set temperature T0 at the time of manufacturing toner M
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0124]   <Comparative Example 1> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 42000, glass transition point Tg: 62 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.20 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Higher alcohol (DSC endothermic peak: 110 ° C) 4 parts by weight

Use of the above materials, barrel set temperature T0 (° C) = 90 ° C, kneader outlet temperature T1 (° C) = 1
Toner N was obtained in the same manner as in Example 1 except that the surface modification of applying a mechanical impact force at 40 ° C. was not carried out. The obtained toner had a weight average diameter of 6.03 μm and a low charge amount of −30 (mC / kg). At this time, the transfer efficiency from the photoreceptor to the transfer material was as low as 80%. No offset occurred during low-temperature fixing, and the fixing strength was sufficient. As a result of the durability test, a slight dropout in the transfer of characters and lines was observed. The fixing roller was good with no stain.

Barrel portion set temperature T0 at the time of manufacturing toner N
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0127]   <Comparative example 2> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.21 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 68 ° C) 4 parts by weight

Using the above materials, barrel temperature T0 (° C) = 90 ° C, kneader outlet temperature T1 (° C) = 1
Toner O was obtained in the same manner as in Example 1 except that the temperature was changed to 35 ° C. The weight average diameter of the obtained toner is 5.99μ.
m, the charge amount was -31 (mC / kg), which was relatively low. At this time, the transfer efficiency from the photosensitive member to the transfer material was as high as 90%, showing a high transfer efficiency, no offset occurred at the time of low temperature fixing, and the fixing strength was sufficient. However, when a standing test was performed in a constant temperature bath at 50 ° C., blocking of the toner was observed. As for the endurance result, voids in the transfer of characters and lines and sleeve ghost were not seen, but the fixing roller was stained.

Barrel portion set temperature T0 at the time of manufacturing toner O
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0130]   <Comparative example 3> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.20 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Polypropylene (DSC endothermic peak: 135 ° C) 4 parts by weight

Using the above materials, barrel temperature T0 (° C) = 90 ° C, kneader outlet temperature T1 (° C) = 1
Toner P was obtained in the same manner as in Example 1 except that the temperature was changed to 50 ° C. The weight average diameter of the obtained toner is 6.93μ.
m, the charge amount was -35 (mC / kg), which was low. At this time, the transfer efficiency from the photoreceptor to the transfer material was as low as 85%. No offset occurred during low-temperature fixing, and the fixing strength was sufficient. As a result of the durability test, a sleeve ghost was observed, and when the surface of the sleeve was observed, a fused substance considered to be a toner was observed on the surface of the sleeve. A slight dropout in the transfer of toner characters and lines was also observed. The fixing roller was good with no stain.

Barrel portion set temperature T0 at the time of manufacturing toner P
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0133]   <Comparative example 4> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 41,000, glass transition point Tg: 65 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.20 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Acid-modified polypropylene (DSC endothermic peak: 138 ° C) 4 parts by weight

Use of the above materials, barrel temperature set T0 (° C) = 130 ° C, kneader outlet temperature T1 (° C) =
Toner Q was obtained in the same manner as in Example 1 except that the temperature was changed to 150 ° C. The weight average diameter of the obtained toner is 7.20μ.
m, the charge amount was -41 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as low as 82%. Offset occurred during low temperature fixing, and sufficient fixing strength could not be obtained.

Barrel portion set temperature T0 at the time of manufacturing toner Q
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0136]   <Comparative Example 5> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 42000, glass transition point Tg: 62 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.22 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Acid-modified polypropylene (DSC endothermic peak: 145 ° C) 4 parts by weight

Use of the above materials, barrel temperature T0 (° C) = 130 ° C, kneader outlet temperature T1 (° C) =
Toner R was obtained in the same manner as in Example 1 except that the temperature was changed to 150 ° C. The weight average diameter of the obtained toner is 7.20μ.
m, the charge amount was -40 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as low as 81%. Offset occurred during low temperature fixing, and sufficient fixing strength could not be obtained.

Barrel portion set temperature T0 at the time of manufacturing the toner R
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0139]   <Comparative example 6> ・ Styrene-butyl acrylate-butyl maleate half ester copolymer (Peak molecular weight: about 45,000, glass transition point Tg: 63 ° C)                                                           100 parts by weight ・ Magnetic iron oxide (average particle size 0.21 μm) 100 parts by weight ・ Monoazo dye chromium complex 2 parts by weight ・ Low molecular weight polyethylene (DSC endothermic peak: 122 ° C) 4 parts by weight

Use of the above materials, barrel temperature T0 (° C) = 170 ° C, kneader outlet temperature T1 (° C) =
Toner S was obtained in the same manner as in Example 1 except that the temperature was changed to 175 ° C. The weight average diameter of the obtained toner is 6.56μ.
m, the charge amount was -41 (mC / kg). At this time, the transfer efficiency from the photoconductor to the transfer material was as low as 82%. Offset occurred during low temperature fixing, and sufficient fixing strength could not be obtained.

Barrel portion set temperature T0 at the time of manufacturing the toner S
(° C.), temperature T1 (° C.) at the outlet of the melt-kneading machine, toner physical properties, and image evaluation results are shown in Tables 1 and 2.

[0142]

[Table 1]

[0143]

[Table 2]

[0144]

According to the magnetic toner and the method for producing the same of the present invention, the following effects can be obtained.

(1) Conditions for melt-kneading, one is to define the temperature of the kneaded product at the outlet of the melt-kneading machine and the viscosity of the wax at that temperature, and the other is to specify the barrel in the kneading section on the tail end side of the screw. By defining the difference between the set temperature and the temperature of the DSC endothermic main peak of the wax, the wax is appropriately dispersed on the surface of the toner particles.

(2) This dispersion state affects the surface property of the toner, improves the charging performance of the toner, and improves the transfer performance.

(3) Further, by defining the shape factor and making the shape less uneven, the degree of influence of the wax exposed on the toner surface can be increased, which can greatly contribute to the charging performance and the fixing performance.

[Brief description of drawings]

FIG. 1 is a diagram showing an image formed by using the toner of the present invention.
It is a schematic diagram of an example of a suitable image forming apparatus.

FIG. 2 is a diagram showing an image formed by using the toner of the present invention.
1 is a schematic diagram of an example of a suitable image forming apparatus of a one-component developing device.

[Explanation of symbols]

100 photoconductor (electrostatic latent image carrier) 102 developing sleeve (toner carrier) 103 Contact blade 104 magnet roller 114 Transfer charging roller 116 cleaner 117 Primary charging roller 121 Laser generator 123 laser light 124 register roller 125 conveyor belt 126 Fixer 140 developer 141 stirring rod

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI G03G 9/083 G03G 9/08 321 101 (72) Inventor Yuki Karaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-6-118713 (JP, A) JP-A-6-95433 (JP, A) JP-A-5-197192 (JP, A) JP-A-9-34163 (JP, A) JP-A-8-328312 (JP, A) JP-A-8-320591 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G03G 9/087 G03G 9/08 365 G03G 9 / 08 371 G03G 9/08 374 G03G 9/08 375 G03G 9/083

Claims (36)

(57) [Claims] 1. A toner mother particle and an inorganic material produced through a step of melt-kneading at least a binder resin, a magnetic substance and a wax using a screw extrusion kneader having a feed screw part and at least one kneading part. In a magnetic toner containing at least fine powder, the viscosity of the wax at T1 (° C) is 12 when the temperature of the kneaded product at the discharge port of the melt kneader is T1 (° C).
˜30 mPa · s , and the binder resin of the magnetic toner contains 5% by weight or less of THF insoluble matter.
And the binder resin is the molecular weight component of GPC of the THF soluble component.
In the cloth, the content (M1) of the component having a molecular weight of less than 50,000 is
40-70%, containing a component having a molecular weight of 50,000 to 500,000.
The content (M2) is 20 to 45% and the molecular weight exceeds 500,000.
The content (M3) of the extractable component is 2 to 25%, and M
A magnetic toner characterized in that 1 ≧ M2 ≧ M3 . 2. The viscosity of the wax at T1 (° C.) is 15 to 25 mPa · s.
The magnetic toner described in 1. 3. When the barrel set temperature in the kneading section on the rearmost side of the screw of the screw extrusion kneader is T0 (° C.) and the temperature of the endothermic main peak of DSC of the wax is T2 (° C.), | T0-T2 | ≦ 30
3. The magnetic toner according to claim 1, wherein the magnetic toner has a temperature of (° C.) and one or more T2 (° C.) in a region of 60 to 120 ° C. 4. 4. A value obtained by subtracting the temperature T2 (° C.) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C.) of the kneaded material at the outlet of the melt kneader, T1 (° C.) − T2 (° C.)
Is from 10 to 60 ° C. 4.
The magnetic toner according to any one of 1. 5. A value obtained by subtracting the temperature T2 (° C.) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C.) of the kneaded material at the outlet of the melt kneader, T1 (° C.)-T2 (° C.)
Is 20 to 50 ° C.
The magnetic toner according to any one of 1. 6. The magnetic toner according to claim 1, wherein the wax has one or more DSC endothermic main peak temperatures T2 (° C.) in a region of 70 ° C. or higher. 7. The magnetic toner according to claim 1, wherein the wax has at least one DSC endothermic main peak temperature T2 (° C.) in a region of 110 ° C. or lower. 8. The wax is any one of a polyolefin wax and a derivative thereof, a hydrocarbon wax and a derivative thereof synthesized by a Fischer-Tropsch method, a petroleum wax and a derivative thereof, and a higher aliphatic alcohol and a derivative thereof. The magnetic toner according to claim 1, wherein the magnetic toner is a magnetic toner. 9. The ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of the wax is 1.0 ≦ Mw / Mn.
9. The magnetic toner according to claim 1, wherein ≦ 2.0. 10. A value C of viscoelasticity tan δ at 100 ° C. of the magnetic toner and a viscoelasticity tan δ at 150 ° C.
The value of the ratio D / C to the value D of is D / C ≧ 1, and the temperature is 150 ° C.
The magnetic toner according to any one of claims 1 to 9 , wherein a value E of viscoelasticity tan δ in a range from 1 to 190 ° C is 3.0 ≧ E ≧ 0.5. 11. magnetic toner, magnetic toner according to any one of claims 1 to 10, characterized in that 100 parts by weight of the binder resin, and a magnetic material containing 30 to 200 parts by weight. 12. The inorganic fine powder contained in the magnetic toner is at least one kind of inorganic fine powder selected from titania, alumina, silica, or a double oxide thereof. 12. The magnetic toner according to any one of 1 to 11 . 13. The magnetic toner according to any one of claims 1 to 12 inorganic fine powder contained in the magnetic toner is characterized in that having been hydrophobic-treated. A magnetic toner according to any one of claims 14] claims 1 to 13 inorganic fine powder contained in the magnetic toner is characterized in that which has been treated with at least silicone oil. 15. The value of the shape factor SF-1 of the magnetic toner particles measured by an image analyzer is 110 <SF-1 ≦ 18.
0, and the value of the shape factor SF-2 is 110 <SF-2 ≦.
140, and the ratio B / A of the value B obtained by subtracting 100 from the value of SF-2 and the value A obtained by subtracting 100 from the value of SF-1 is 1.0 or less. 15. The magnetic toner according to any one of 1 to 14 . 16. The shape factor SF-1 of the magnetic toner particles measured by an image analyzer is 120 <SF-1 ≦ 16.
0 and the value of the shape factor SF-2 is 115 <SF-2 ≦.
140, and the ratio B / A of the value B obtained by subtracting 100 from the value of SF-2 and the value A obtained by subtracting 100 from the value of SF-1 is 1.0 or less. 15. The magnetic toner according to any one of 1 to 14 . 17. magnetic toner toner manufacturing process, according to any one of claims 1 to 16, characterized in that at least mechanical impact spheronization process adding is made to the toner particles Magnetic toner. 18. The magnetic toner has a weight average diameter of 8.0.
The magnetic toner according to any one of claims 1 to 17 , wherein the magnetic toner has a thickness of not more than μm. 19. Toner base particles are produced through a step of melt-kneading at least a binder resin, a magnetic material and a wax using a screw extrusion kneader having a feed screw section and at least one kneading section, and obtaining the toner mother particles. In the method for producing a magnetic toner produced by mixing the obtained toner mother particles and at least an inorganic fine powder, when the temperature of the kneaded product at the discharge port of the melt kneader is T1 (° C), The viscosity of wax is 12
˜30 mPa · s , and THF insoluble content of the binder resin of the magnetic toner is 5% by weight or less.
And the binder resin is the molecular weight component of GPC of the THF soluble component.
In the cloth, the content (M1) of the component having a molecular weight of less than 50,000 is
40-70%, containing a component having a molecular weight of 50,000 to 500,000.
The content (M2) is 20 to 45% and the molecular weight exceeds 500,000.
The content (M3) of the extractable component is 2 to 25%, and M
A method of manufacturing a magnetic toner, wherein 1 ≧ M2 ≧ M3 . 20. The viscosity of the wax at T1 (° C.) is 15 to 25 mPa · s.
20. The method for producing a magnetic toner according to Item 19 . 21. When the barrel temperature in the kneading portion on the rearmost side of the screw of the screw extrusion kneader is T0 (° C.) and the temperature of the endothermic main peak of DSC of the wax is T2 (° C.), | T0-T2 | ≦ 3
0 (° C.) and is, and T2 (° C.) according to claim 19 or, characterized in that has more than one in the region of 60 to 120 ° C.
21. The method for producing a magnetic toner according to 20 . 22. A value obtained by subtracting the temperature T2 (° C.) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C.) of the kneaded product at the outlet of the melt kneader, T1 (° C.) − T2.
Claim (℃) is characterized in that it is a 10 to 60 ° C. 1
22. A method for producing a magnetic toner according to any one of 9 to 21 . 23. A value obtained by subtracting the temperature T2 (° C.) of the endothermic main peak of the DSC of the wax from the temperature T1 (° C.) of the kneaded product at the outlet of the melt kneader, T1 (° C.) − T2.
Claim (℃) is characterized in that it is a 20 to 50 ° C. 1
22. A method for producing a magnetic toner according to any one of 9 to 21 . 24. Temperature of the endothermic main peak of DSC of the wax T2 (° C.) The production of the magnetic toner according to any one of claims 19 to 23, characterized in that it has one or more 70 ° C. or more regions Method. 25. The temperature of the endothermic main peak of DSC of the wax T2 (° C.) The production of the magnetic toner according to any one of claims 19 to 24, characterized in that it has one or more 110 ° C. the following areas Method. 26. The wax, low molecular weight polyethylene, low molecular weight hydrocarbon waxes, method for producing a magnetic toner according to any one of claims 19 to 25, characterized in that either a higher alcohol. 27. The ratio Mw / Mn of the weight average molecular weight Mw and the number average molecular weight Mn of the wax is 1.0 ≦ Mw / M.
claim, characterized in that a n ≦ 2.0 19 to 26
5. The method for producing a magnetic toner according to any one of 1. 28. The value C of viscoelasticity tan δ at 100 ° C. of the magnetic toner and the viscoelasticity tan δ at 150 ° C.
The value of the ratio D / C to the value D of is D / C ≧ 1, and the temperature is 150 ° C.
The value of viscoelasticity tanδ in the range from 190 ° C. E is characterized by a 3.0 ≧ E ≧ 0.5 Claim 19
28. A method for manufacturing a magnetic toner according to any one of items 27 to 27 . 29. magnetic toner, 100 parts by weight of the binder resin, the magnetic toner according to any one of claims 19 to 28, characterized in that it the magnetic containing 30 to 200 parts by weight Production method. 30. The method of claim 19, wherein the inorganic fine powder contained in the magnetic toner is titania, alumina, silica, or one or more inorganic fine powder selected from among those mixed oxide, 30. The method for producing a magnetic toner according to any one of items 29 to 29 . 31. The inorganic fine powder contained in the magnetic toner is hydrophobized.
31. The method for producing a magnetic toner according to any one of 19 to 30 . 32. A method for producing a magnetic toner according to any one of claims 19 to 31, wherein the inorganic fine powder contained in the magnetic toner is one that was treated with at least silicone oil. 33. The value of the shape factor SF-1 of the magnetic toner particles measured by an image analyzer is 110 <SF-1 ≦ 18.
0, and the value of the shape factor SF-2 is 110 <SF-2 ≦.
Was 140, claim, wherein the ratio B / A between the value obtained by subtracting 100 from the values of B and SF-1 minus 100 from the value of SF-2 A is 1.0 or less 19 Through 32
5. The method for producing a magnetic toner according to any one of 1. 34. The value of the shape factor SF-1 of the magnetic toner particles measured by an image analyzer is 120 <SF-1 ≦ 16.
0 and the value of the shape factor SF-2 is 115 <SF-2 ≦.
Was 140, claim, wherein the ratio B / A between the value obtained by subtracting 100 from the values of B and SF-1 minus 100 from the value of SF-2 A is 1.0 or less 19 Through 32
5. The method for producing a magnetic toner according to any one of 1. 35. A magnetic toner, in the manufacturing process of the toner, claims 19 to 34, characterized in that at least mechanical impact spheronization process to add to the toner particles
5. The method for producing a magnetic toner according to any one of 1. 36. The magnetic toner has a weight average diameter of 8.0.
method for producing a magnetic toner according to any one of claims 19 to 35, characterized in that μm or less.