JP3119395B2 - Method for producing toner composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a toner composition for developing an electrostatic image and a magnetic latent image in electrophotography, electrostatic printing, magnetic recording and the like. In particular, the present invention relates to a method for producing a toner composition to be subjected to a heat fixing method such as heat roller fixing.

[0002]

2. Description of the Related Art U.S. Pat.
A number of methods are known as described in JP-A-69-169, JP-B-42-23910, JP-B-43-24748, and the like. Means for forming an electric latent image on the photoreceptor, developing the latent image with toner, and transferring the toner image to a transfer material such as paper as necessary, and then heating, pressure, and heating / pressing. Alternatively, the toner is fixed by a solvent vapor or the like to obtain a copy, and the remaining toner not transferred onto the photoreceptor is cleaned by various methods, and the above-described steps are repeated.

In recent years, such copying apparatuses have become smaller and smaller.
Lighter weight, higher speed, and higher reliability have been strictly pursued, and as a result, the performance required for toners has also become higher. For example, various methods and apparatuses have been developed for the process of fixing a toner image on a sheet such as paper, but the most common method at present is a heat compression method using a heat roller. The heat compression bonding method using a heat roller performs fixing by allowing the toner image surface of a sheet to be fixed to pass through the surface of a heat roller having a surface formed of a material having releasability with respect to toner while contacting the surface under pressure. . In this method, since the surface of the heat roller and the toner image of the sheet to be fixed come into contact with each other under pressure, the heat efficiency when fixing the toner image on the sheet to be fixed is extremely good, and the fixing can be performed quickly. It is very effective in high-speed electrophotographic copying machines. However, since the surface of the heat roller and the toner image come into contact with each other in a molten state under pressure, a part of the toner image adheres to and transfers to the surface of the heat roller, and this re-transfers to the next sheet to be fixed, causing a so-called offset phenomenon. The sheet to be fixed may be stained. For this reason, it is regarded as one of the essential conditions of the heat roller fixing method that the toner does not adhere to the surface of the heat roller.

Conventionally, for the purpose of preventing toner from adhering to the surface of a heat roller, for example, the surface of the roller is formed of silicone rubber or fluorine resin which is a material having excellent releasability from the toner, and the surface of the roller is prevented from being offset. In order to prevent the roller surface from being fatigued, the roller surface is coated with a thin film of a liquid having good releasability such as silicone oil. However, this method is effective in preventing the offset phenomenon, but has a problem that a fixing device is required because a device for supplying an anti-offset liquid is required. This is opposite to the reduction in size and weight of the copying machine, and moreover, silicon oil and the like may be evaporated by heat and contaminate the inside of the copying machine. Therefore, a method of adding a release agent such as a low-molecular-weight polyolefin to the toner is considered in order to provide the toner itself with offset resistance without using an offset prevention liquid supply device or the like. In order to achieve both the fixing property and the offset resistance, a method of using a binder resin having two peaks in the molecular weight distribution as a binder resin of the toner, a method of adding waxes to the binder resin in advance, and the like have been proposed.

The method described in, for example, JP-A-52-3
No. 304, JP-A-52-3305, JP-A-5-3
JP-A-7-52574, JP-A-58-215659, JP-A-60-217366, and JP-A-60-2
No. 52361, Japanese Patent Application Laid-Open No. 60-252362 and the like are disclosed.
JP-A-6-16144, JP-A-2-23569, JP-A-63-127254, JP-A-3-26
No. 831 is disclosed.

[0006] However, by merely including a certain release agent in the toner or by using a binder resin having two peaks in the molecular weight distribution, a certain degree of improvement in fixing property and offset resistance can be seen. Since the resin and the wax are melt-mixed during melt-kneading in toner production, uneven distribution and release of the wax component due to poor dispersibility of the wax are liable to occur, thereby causing image stains such as fog, photosensitive members, etc. It may cause fusion, filming, and the like. Further, the low molecular weight component and the high molecular weight component do not mix well, and the binder resin composition of the toner becomes non-uniform or other materials cannot be dispersed uniformly, which adversely affects the fixing property, the anti-offset property and the developing property. Therefore, for example, when the kneading conditions at the time of melt-kneading are strengthened in order to improve the compatibility and dispersibility of the toner components, the molecular weight of the toner decreases due to breaking of the molecular chain of the binder resin in the toner due to kneading. However, there arise problems such as deterioration of the offset resistance, particularly the offset resistance on the high temperature side. In addition, when a large amount of wax is added in order to exert a sufficient effect on the offset resistance, the blocking resistance is deteriorated and the dispersion of the wax is further deteriorated, and the surface of the toner carrier such as a carrier or a sleeve is deteriorated. It is contaminated, and the image deteriorates, which is a practical problem.

For example, Japanese Patent Application Laid-Open No.
JP-A-2-195683, JP-A-3-185458, JP-A-56-87051, JP-A-2-257
No. 8, JP-A-2-12160, and the like.

[0008] This method has better wax dispersibility and improved anti-offset property as compared with the above method.
There are problems that the dispersibility of the wax is still insufficient and the offset resistance is still poor. Furthermore, when a wax is added at the time of polymerization, there is an adverse effect such that polymerization inhibition is caused, the molecular weight is reduced, and residual monomers are increased.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a toner composition which solves the above-mentioned problems.

That is, an object of the present invention is to provide a method for producing an excellent toner composition which is free from uneven distribution and release of the constituents of toner particles, and is free from fogging and image deterioration.

Another object of the present invention is to provide a method for producing a toner composition in which a wax is uniformly dispersed in a toner, the compatibility of resin components is good, and the offset resistance is excellent.

It is another object of the present invention to provide a toner composition having excellent hot offset resistance, which can suppress the molecular chain breakage of the toner binder resin because it is not necessary to excessively strengthen the melt-kneading conditions during toner production. It is to provide a manufacturing method.

Still another object of the present invention is that since the wax is uniformly dispersed in the toner, there is no problem in terms of quality even if the fine powder generated in the subsequent step (crushing and classification) of the melt-kneading step is reused. An object of the present invention is to provide a method for producing a toner composition that can be efficiently and continuously produced.

[0014]

According to the present invention, the weight average molecular weight (Mw) is 4000 to 50,000, and the ratio (Mw / Mn) of the weight average molecular weight to the number average molecular weight (Mn) is less than 3.5. Resin (A) 50 to 90 parts by weight and resin (B) 5 having a weight average molecular weight (Mw) of 400,000 or more
0 to 10 parts by weight and one or more waxes are mixed in a solution in the presence of a solvent (however, when the resin (B) is dissolved in the solvent, the wax coexists) and the solvent is removed. The present invention relates to a method for producing a toner composition, which comprises melting and kneading a binder resin and another material.

In melting and kneading, the melting point of the wax is 20
It is preferable that the melt-kneading is performed at a temperature not lower than 0 ° C. and a temperature not higher than 60 ° C. than the melting point of the wax, and it is also preferable to perform the melt-kneading while performing ventilation.

The solution mixing method of the binder resin according to the present invention comprises:
Unless a method of previously dissolving only the resin (B) in a solvent and dissolving only the resin (A) and the resin (B) in a solvent are not used, the resin (A), the resin (B) and It is possible to mix the wax in solution. If the wax is not present in the mixed system when the resin (B) having a high molecular weight is dissolved, the viscosity of the mixed solution is increased, so that the molecular chains of the binder resin are cut and the molecular weight is reduced. This is not preferred because the compatibility between the resin and the resin (B) deteriorates and the dispersibility of the wax decreases.

As a specific method of solution mixing, there are the following methods (1) to (4). Resin (A) is added to a solution in which only wax is dissolved in a solvent.
And adding the resin (B) [in any order or simultaneously] and dissolving. A method in which wax is dissolved in a solution in which only the resin (A) is dissolved in a solvent [or a solution polymerization solution of the resin (A)], and then the resin (B) is dissolved. [Wax and resin (B)
May be simultaneously dissolved.] A method in which a solution in which the wax and the resin (B) are dissolved in a solvent in advance is added to the resin solution (A). A method in which the resin (A), the resin (B) and the wax are simultaneously dissolved in a solvent.

According to these methods, since the wax is present in the mixed system, the increase in the viscosity of the solution due to the dissolution of the resin is suppressed, and the shearing force at the time of stirring does not act on the action of cutting the molecular chains of the binder resin. The resin (A) and the resin (B) act as a more uniform solution. Further, a solvent and the like are easily removed at the time of solvent removal, so that a binder resin having a small amount of residual monomer and residual solvent can be obtained.

When the low molecular weight resin (A) and the high molecular weight resin (B) are mixed in a solution as described above, the wax is uniformly dispersed in the binder resin by the presence of the wax in the system. Not only is achieved, but also a binder resin in which the low molecular weight resin (A) and the high molecular weight resin (B) are uniformly mixed and mixed can be produced. Therefore, by using the binder resin, other materials can be uniformly dispersed in the binder resin at the time of melt-kneading. That is, if the low molecular weight resin component and the high molecular weight resin component are not well compatible with each other in the binder resin, a local difference in melt viscosity occurs in the subsequent melt kneading step, which causes poor dispersion and segregation of other materials.

The resin (A) in the present invention has a weight average molecular weight Mw of 4000 to 50,000, and a ratio Mw / Mn of the weight average molecular weight to the number average molecular weight of less than 3.5. Fusing and sticking to the toner carrying member occur. Even when the molecular weight is within the above range, when Mw / Mn is 3.5 or more, fusion and fixation are apt to occur near the lower limit of the molecular weight, and the fixability deteriorates near the upper limit of the molecular weight. Preferably, the weight average molecular weight Mw is 5,000 to 40000, and the ratio Mw / Mn of the weight average molecular weight to the number average molecular weight is less than 3.0.

The resin (B) used in the present invention has a weight average molecular weight Mw of 400,000 or more. If the molecular weight is less than the molecular weight, the offset resistance of the toner at high temperatures deteriorates. Further, it is preferable that the upper limit of Mw is not more than 1500000 in order to achieve uniform mixing and compatibility with the resin (A). More preferably, the weight average molecular weight Mw is in the above range and the weight average molecular weight and Ratio M to number average molecular weight
w / Mn is less than 10, more preferably Mw / Mn is 5
Less is better.

The mixing weight ratio of the resin (A) and the resin (B) is such that (A: B) is 50:50 to 90:10. When the amount of the resin (B) is more than this range, the fixability of the toner deteriorates. . In addition, the viscosity increases when mixing the solution, the compatibility between the resins,
The dispersibility of the wax deteriorates, or the molecular chains of the binder resin are cut. Further, even if such a binder resin and other materials are melt-kneaded, poor dispersion and segregation of other materials are caused. On the other hand, when the amount of the resin (B) is less than the above range, the high-temperature offset resistance of the toner deteriorates. Preferably, the mixture weight ratio (A: B) is 55:45 to 85:15.

The amount of the wax added is preferably 0.5 to 10 parts by weight based on 100 parts by weight of the whole resin. In addition, 2
Two or more waxes may be used in combination.

In order to obtain the toner composition according to the present invention, the binder resin obtained by the present invention and other materials, such as a charge control agent, a magnetic material, a pigment, a dye, and other additives, may be used as needed. A method in which the mixture is sufficiently premixed by a ball mill or other mixer and then melt-kneaded using a kneader such as a heating roll, a kneader, or an extruder is used. Then, after cooling and solidifying, coarsely pulverized by a hammer mill or the like, and adjusted to a desired particle size by a fine pulverizer or a classifier, a toner is obtained.

From the viewpoint of productivity, the kneader is preferably an extruder type kneader capable of continuous production, but is not particularly limited.

It is preferable to melt-knead at a temperature 20 ° C. lower than the melting point of the wax. This is because the wax component finely dispersed in the binder resin is melted by heat first, and the melt viscosity of the binder resin at the time of melt-kneading is efficiently reduced, and the shearing force is higher than the force required for dispersing the toner components. Is suppressed from being applied to the binder resin, so that the molecular chain of the binder resin, in particular, the polymer chain can be prevented from being cut. If the kneading is performed at a temperature lower than the melting point of the wax by 20 ° C. or less, the shearing force is strongly applied to the binder resin before the wax is melted by heat, so that the polymer chains may be cut.

Further, it is preferable to melt-knead at a temperature not higher than 60 ° C. higher than the melting point of the wax. When melt-kneaded at a temperature higher than the melting point of the wax by 60 ° C. or more, the melt viscosity of the wax component drops extremely, and at the same time, the melt viscosity of the binder resin drops more than necessary, causing re-aggregation of the wax component and other materials (charge control). Agent, coloring agent, magnetic material, etc.).

That is, melting and kneading at a temperature not lower than the melting point of the wax by 20 ° C., preferably not lower than the melting point of the wax and not higher than the melting point of the wax by 60 ° C., preferably not higher than the temperature of the melting point of the wax by 50 ° C. Good for preventing dispersion and molecular chain breakage.

In addition, a toner with less residual monomer and residual solvent can be obtained by air suction of a ventro such as an extruder during melt-kneading. Since the wax is dispersed in the binder resin in advance, the solvent removal of the solution-mixed resin is easy. The volatile content of the binder resin after solvent removal,
It is preferably at most 1.0% by weight, more preferably at most 0.5% by weight, particularly preferably at most 0.3% by weight. Further, the residual monomer of the toner obtained by the above-mentioned melt-kneading method, The amount of residual solvent is 1
00 ppm or less and 1000 ppm or less are achievable and preferred. If these residual amounts are large, odor may be generated at the time of fixing the toner, and the storage stability and the blocking resistance of the toner may be deteriorated.

The resins (A) and (B) used in the present invention include styrene, α
Styrene such as methyl styrene, p-methyl styrene, p-chloro styrene and vinyl toluene and substituted products thereof; acrylates such as methyl acrylate, ethyl acrylate, n-butyl acrylate and t-butyl acrylate; Methyl methacrylate, ethyl methacrylate,
Methacrylic esters such as n-butyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate; acrylonitrile; vinyl ethers such as vinyl methyl ether and vinyl ethyl ether; maleic acid and maleic ester Unsaturated carboxylic acids, unsaturated carboxylic esters;
Examples thereof include olefins such as ethylene, propylene and butadiene, and diolefins. Monomers of these monomers, and copolymers of two or more monomers, and polyesters, non-linear polyesters, polyethers, polyamides, epoxy resins, polyamides, terpene resins, phenolic resins, alone or Can be mixed and used.

In the polymerization of the above-mentioned monomers, the polymerization can be carried out in the presence of an initiator and in the presence or absence of a crosslinking agent.

Of these, styrene-acrylate copolymers, styrene-methacrylate copolymers, and polyester resins are particularly preferred.

The resin (A) and the resin (B) in the present invention are not particularly limited as long as they are within the above-mentioned molecular weight ranges.

As the initiator, t-butylperoxy-
2-ethylhexanoate, cumin perpivalate t-
Butylperoxylaurate, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2,
2'-azobisisobutyronitrile, 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'azobis (4-methoxy −2,4-dimethylvaleronitrile), 1,1-bis (t-butylperoxy) 3,3
5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, 1,4-bis (t-
Butylperoxycarbonyl) cyclohexane, 2,2
-Bis (t-butylperoxy) octane, n-butyl 4,4-bis (t-butylperoxy) valerate,
2,2-bis (t-butylperoxy) butane, 1,3
-Bis (t-butylperoxy-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-
Butylperoxy) hexane, 2,5-dimethyl-2,
5-di (benzoylperoxy) hexane, di-t-butyldiperoxyisophthalate, 2,2-bis (4
4-di-t-butylperoxycyclohexyl) propane, di-t-butylperoxy α-methylsuccinate, di-t-butylperoxydimethylglutarate,
Di-t-butylperoxyhexahydroterephthalate, di-t-butylperoxyazelate, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, diethylene glycol bis (t-butylperoxycarbonate) ), Di-t-butylperoxytrimethyladipate, tris (t-butylperoxy) triazine, vinyltris (t-butylperoxy) silane, and the like, which can be used alone or in combination.

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

The wax of the present invention has a number average molecular weight (Mn) of 8.0 × 10 ³ or less and a weight average molecular weight (M
It is preferable that w) is 2.5 × 10 ⁴ or less. Further, the melting point is preferably from 70 to 165 ° C, particularly preferably from 75 to 150 ° C.

The wax used in the present invention includes paraffin wax, microwax, ethylene, propylene, butene-1, pentene-1, hexene-1, heptene-1, octene-1, nonene-1, and decene-1. Homopolymerization of such linear α-olefins, branched α-olefins having a branched portion at the terminal, and olefins having different positions of unsaturated groups thereof, and copolymers thereof are exemplified.

Note that there is no particular limitation.

As the organic solvent used in the present invention, for example, toluene, xylene, cumene, benzene, dichlorobenzene, hexane, cyclohexene, chloroform,
There are methyl ethyl ketone (MEK), tetrahydrofuran (THF), cellosolve acetate, alcohols, ethers and the like, which may be used alone or in combination.

In the present invention, the molecular weight distribution of the resin and the wax is measured by GPC (gel permeation chromatography) under the following conditions.

<GPC Measurement Conditions for Resin> Apparatus: GPC-150 (manufactured by Waters) Column: KF801 to 7 (manufactured by Shodex) Temperature: 40 ° C. Solvent: THF (tetrahydrofuran) Flow rate: 1.0 ml / min. Sample: 0.1 ml of a sample having a concentration of 0.05 to 0.6 wt%
Injection (However, the concentration of resin (B) should be 0.15% or less)

<GPC Measurement Conditions for Wax> Apparatus: GPC-150C (manufactured by Waters) Column: Duplex of GMH-HT (manufactured by Tosoh Corporation) Temperature: 135 ° C. Solvent: o-dichlorobenzene (addition of 0.1% ionol) ) Flow rate: 1.0 ml / min. Sample: 0.4 ml of 0.15% sample is injected

Measurement is performed under the above conditions, and the molecular weight of the sample is calculated using a molecular weight calibration curve prepared from a monodisperse polystyrene standard sample. Further, the molecular weight of the wax is calculated by conversion using a conversion formula derived from the Mark-Houwink viscosity formula.

The melting point of the wax is determined by a high-precision internal heating type input compensation type differential scanning calorimeter (DSC manufactured by PerkinElmer).
-7) using a heating rate of 10 ° C./min. ASTM
It is measured according to the temperature measurement pattern of D3418, and is set as the peak top value of the maximum melting temperature.

In the present invention, a conventionally known positive or negative charge control agent is used as the charge control agent. today,
The charge control agents known in the technical field include the following.

(1) The following substances control the toner to be positively charged. Modified products such as nigrosine and fatty acid metal salts, quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate, and oniums such as phosphonium salts which are analogs thereof Salts and these lake pigments, triphenylmethane dyes and these lake pigments,
(As a lake-forming agent, phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.) Metal salts of higher fatty acids; dibutyltin oxide, dioctyltin oxide And diorganotin oxides such as dicyclohexyltin oxide; diorganotin borates such as dibutyltin borate, dioctyltin borate and dicyclohexyltin borate; and these can be used alone or in combination of two or more. Of these, charge control agents such as nigrosine, quaternary ammonium salts, and triphenylmethane lake pigments are particularly preferably used.

In addition, the general formula

[0048]

[Outside 1] [R ₁ : H, CH ₃ R ₂ , R ₃ : a substituted or unsubstituted alkyl group (preferably C ₁ -C ₄ )] homopolymer of a monomer: styrene, acrylate, methacrylic acid described above A copolymer with a polymerizable monomer such as an ester can be used as a positive charge control agent. In this case, these charge control agents also act as (all or part of) the binder resin.

The following substances control the toner to be negatively charged.

For example, organic metal complexes and chelate compounds are effective, and examples thereof include monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acids, and aromatic dicarboxylic acid-based 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.

The toner of the present invention can provide good results when additives are mixed as necessary. As the additive, for example, a lubricant such as Teflon, zinc stearate, and polyvinylidene fluoride, among which polyvinylidene fluoride is preferable. Alternatively, abrasives such as cerium oxide, silicon carbide, and strontium titanate, among which strontium titanate is preferable. Alternatively, for example, a fluidity-imparting agent such as colloidal silica and aluminum oxide, particularly hydrophobic colloidal silica is preferable. It is also possible to use an anti-caking agent or a conductivity-imparting agent such as carbon black, zinc oxide, antimony oxide and tin oxide. Further, a small amount of white fine particles and black fine particles of opposite polarity can be used as a developing property improver.

When the toner of the present invention is used as a two-component developer, it is used by mixing with a carrier powder. In this case, the mixing ratio between the toner and the carrier powder is 0.1 to 50% by weight, preferably 0.1% by weight, as the toner concentration.
5 to 15% by weight, more preferably 3 to 5% by weight is desirable.

In the present invention, known carriers can be used, for example, magnetic powders such as iron powder, ferrite powder and nickel powder, glass beads and the like, and the surfaces thereof are made of fluorine resin or acrylic resin. Alternatively, those treated with a silicon resin or the like may be used.

Further, the toner of the present invention can be used as a magnetic toner by further containing a magnetic material. In this case, the magnetic material also serves as a colorant. Examples of the magnetic material contained in the magnetic toner of the present invention include iron oxide such as magnetite, hematite, and ferrite or a compound of a divalent metal and iron oxide; iron, cobalt, a metal such as nickel, or aluminum of these metals; Examples include alloys of metals such as cobalt, copper, lead, magnesium, tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

These ferromagnetic materials have an average particle of 0.1 to 2
μm, preferably about 0.1 to 0.5 μm. The amount to be contained in the toner is 100 resin components.
The amount is preferably about 20 to 200 parts by weight, particularly preferably 40 to 150 parts by weight, based on 100 parts by weight of the resin component.

Further, a coloring agent may be added to the toner of the present invention as needed.

In the present invention, any suitable pigment or dye is used as a coloring agent. Toner colorants are well known and include pigments such as carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengara, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient to maintain the optical density of the fixed image, and are preferably added in an amount of 0.1 to 20 parts by weight, preferably 0.2 to 10 parts by weight based on 100 parts by weight of the resin. A dye is further used for the same purpose. For example, azo dyes, anthraquinone dyes,
There are xanthene dyes, methine dyes and the like, and 0.1 to 20 parts by weight, preferably 0.3 to 1 part by weight, per 100 parts by weight of the resin.
The addition amount of 0 parts by weight is good.

Further, if necessary, desired additives are sufficiently mixed by a mixer such as a Hexchel mixer to obtain the toner for developing an electrostatic image according to the present invention.

The toner of the present invention can be applied to plain paper or an overhead projector (OH
The sheet is heat-fixed to a transfer material such as a transparent sheet for P).

As the contact heating fixing means, a heating and pressurizing roll fixing device or a fixedly supported heating body is brought into pressure contact with the heating body, and the transfer material is brought into close contact with the heating body via a film. A surf fixing unit that heats and fixes the toner with the pressing member can be used.

FIG. 1 shows an example of the fixing means.

[0062]

The present invention will be described below in more detail with reference to Synthesis Examples, Production Examples, Examples, etc., but these do not limit the present invention in any way. The parts in the text indicate parts by weight, the ratio indicates the weight ratio, and% indicates the weight%.

[Synthesis Example of Resin] Synthesis Example of Low-Molecular-Weight Resin Component [Synthesis Example 1, Comparative Synthesis Example 1] Synthesis Example 1 Using xylene as a solvent, 83 parts of styrene monomer,
A mixed solution of 17 parts of butyl acrylate and 5 parts of di-t-butyl peroxide was added dropwise, and solution polymerization was performed at xylene reflux temperature to obtain a polymerization solution of resin A-1. The polymerization average molecular weight (Mw) of this resin was 14,700 and Mw / M
n was about 2.4.

Comparative Synthetic Example 1 Solution polymerization was carried out in the same manner as in Synthetic Example 1 except that 1.5 parts of di-t-butyl peroxide was used to obtain a polymerization solution of resin A-2. The weight average molecular weight (Mw) of this resin is 68,
300, Mw / Mn was about 2.7.

Synthesis Example of High Molecular Weight Resin Component [Synthesis Example 2, Synthesis Example 3, Comparative Synthesis Example 2] Synthesis Example 2 A 0.1% aqueous solution of poval was used as a dispersion medium, and 80 parts of styrene monomer and 20 parts of butyl acrylate were added. Part, and 2,
0.2 parts of 2-bis (4,4-di-t-butylperoxycyclohexyl) propane and 0.0 parts of divinylbenzene
Five parts were added to prepare a suspension dispersion, and suspension polymerization was performed at 80 ° C. to obtain a resin B-1. The weight average molecular weight (M
w) was 960,000, and Mw / Mn was about 4.5.

Synthesis Example 3 A suspension polymerization was carried out in the same manner as in Synthesis Example 2 except that divinylbenzene was not added, to obtain a resin B-2. The weight average molecular weight (Mw) of this resin was 760,000, and Mw / Mn was about 3.8.

Comparative Synthesis Example 2 A suspension polymerization was conducted in the same manner as in Synthesis Example 2 except that 1.0 part of 2,2-bis (4,4-di-t-butylperoxycyclohexyl) propane was used and divinylbenzene was not added. Was carried out to obtain a resin B-3. (Mw) of this resin is 340,
000, Mw / Mn was about 3.3.

[Production Example of Binder Resin ] A solution polymerization solution of binder resin-1 resin A-1 (as a low molecular weight resin component) was mixed with resin B-2 (as a high molecular weight resin component) and polyethylene wax (Mn). = 1,100, Mw = 5,88
0, melting point 131 ° C.) (the solid content ratio at this time should be A-1: B-2: wax = 70: 30: 4), and after stirring for about 3 hours, xylene Was removed to obtain Binder Resin-1. The volatile content of this resin is 0.20
%Met.

Comparative Binder Resin-1 In the production of Binder Resin-1, instead of Resin B-2, resin B
Comparative Binder Resin-1 was obtained in the same manner except that a resin solution in which -2 was dissolved in xylene was used. The weight average molecular weight (Mw) of the resin B-2 previously dissolved is 380,000,
w / Mn was changed to about 5.1.

In the production of Comparative Binder Resin-2 and -3 , Resin A-
A binder resin was produced in the same manner except that the resin A-2 was used in place of 1 to obtain a comparative binder resin-2. A binder resin was produced in the same manner as in the production of binder resin-1, except that resin B-3 was used instead of resin B-2 as a high molecular weight resin component, to obtain comparative binder resin-3.

Comparative Binder Resin-4 Comparative Binder Resin-4 was obtained in the same manner as in the production of Binder Resin-1, except that polyethylene wax was not added.

Binder resin-2 In a solution polymerization solution of resin A-1 (as a low molecular weight resin component), resin B-1 (as a high molecular weight resin component) and polypropylene wax (Mn = 1,200, Mw = 6) , 60
0, melting point = 145 ° C.) at the same time (the solid content ratio at this time should be A-1: B-1: wax = 80: 20: 4) and stirred for about 3 hours. Xylene was removed to obtain Binder Resin-2. The volatile content of this resin is 0.1
8%.

In the production of Comparative Binder Resin-5,6 Binder Resin-2, A-1: B-1: wax = 4
In the same manner except that 0: 60: 4, A-1:
A comparative binder resin-5 and a comparative binder resin-6 were respectively obtained in the same manner except that B-1: wax = 92: 8: 4. The volatile content of Comparative Binder Resin-5 was 0.55%.

Example 1 Binder Resin-1 100 parts Magnetic component 80 parts Nigrosine 2 parts

The mixture was premixed at the above ratio, melt-kneaded at a set temperature of 150 ° C. and a main shaft rotation number of 150 while suctioning a ventro with a twin-screw kneading extruder.
Classification was performed to obtain a toner having a weight average particle size of about 9 μm. To 100 parts of the toner, 0.6 part of hydrophobic colloidal silica was externally added and mixed to obtain Toner-1.

Also, only the fine coarse powder sorted in the pulverizing / classifying step was re-kneaded, and after re-kneading, a reused toner-1 was obtained in the same manner.

When these toners were observed with a microscope,
There was no uneven distribution or release of the wax in the toner, and the dispersion state of other materials was good.

Example 2 In the same manner as in Example 1, except that binder resin-2 was used in place of binder resin-1, toner-2 and reused toner-2 were used.
I got

When these toners were observed with a microscope,
There was no uneven distribution or release of the wax in the toner, and the dispersion state of other materials was good.

Example 3 A toner 3 and a reused toner 3 were obtained in the same manner as in Example 1 except that the kneading conditions were changed to the set temperature of 100 ° C. Example 1
There was no problem except that the high-temperature offset resistance was slightly inferior to the above.

Example 4 A toner 4 and a reused toner 4 were obtained in the same manner as in Example 1 except that the kneading conditions were set to a set temperature of 200 ° C. There was no problem except that some fog was initially observed as the developing characteristics of the reused toner 4. When the toner was observed under a microscope, a small amount of free wax was found to be mixed.

Example 5 A toner 5 was obtained in the same manner as in Example 1 except that kneading was performed without suction from a ventro. As compared with Example 1, there was no problem except that the residual monomer and the residual solvent in the toner slightly increased.

Comparative Example 1 Comparative toner 1 was obtained in the same manner as in Example 1 except that comparative binder resin-1 was used instead of binder resin-1. As compared with Example 1, the high-temperature offset resistance was at a level that was considerably inferior and a problem.

Comparative Example 2 Comparative toner 2 was obtained in the same manner as in Example 1 except that comparative binder resin-2 was used instead of binder resin-1. Compared with the first embodiment, the fixable temperature was raised to a problematic level. Further, the pulverizability of the toner during the production was deteriorated, and the production efficiency was lowered.

Comparative Example 3 Comparative toner 3 was obtained in the same manner as in Example 1, except that comparative binder resin-3 was used instead of binder resin-1. As compared with Example 1, the high-temperature offset resistance was at a level that was considerably inferior and a problem.

Comparative Example 4 Comparative Example 4 was repeated, except that the binder resin-1 was used in place of the binder resin-1, and 4 parts of the same polyethylene wax as that added to the binder resin-1 was added. The comparative toner 4 and the reuse comparative toner 4 were obtained in the same manner as in Example 1 except that the kneading conditions in Example 1 were set to 200 ° C. This is a level at which fogging becomes a problem as a developing characteristic of the reuse comparative toner 4, and filming occurs on the photosensitive drum. Microscopic observation of this toner showed that a considerable amount of free wax was mixed.

[0087] The kneading conditions in Comparative Example 4 _a comparative example 4, was obtained comparative toner 4 _a and reuse Comparative Toner 4 _a similarly except that the set temperature 100 ° C.. Filming not the level but there is a slight fogging initially as a development characteristic of the reuse Comparative Toner 4 _a problematic was also not occur. However, the high-temperature offset resistance was at a level that was considerably inferior and a problem.

Comparative Example 5 Comparative toner 5 was obtained in the same manner as in Example 1, except that comparative binder resin-5 was used instead of binder resin-1. Compared with the first embodiment, the fixable temperature rises to a level that causes a problem, and the developing characteristics are such that not only fog but also image density is low and a problem occurs. Further, the pulverizability of the toner during the production was remarkably deteriorated, and the production efficiency was sharply reduced. The residual monomer residual solvent in the toner considerably increased, and an unpleasant odor was generated during fixing by heating.

Comparative Example 6 Comparative toner 6 was obtained in the same manner as in Example 1 except that comparative binder resin-6 was used instead of binder resin-1. As compared with Example 1, the high-temperature offset resistance was considerably inferior and was at a problematic level.

Next, a method for evaluating the above toner will be described.

<Fixing / Offset Test> Commercial Copier N
A fixing unit of P-1010 (manufactured by Canon Inc.) was taken out, and a heat roller external fixing unit with variable process speed and variable temperature was used. Unfixed image passing speed is 50mm
/ S fixed, and a fixed image is applied with a load of 50 g / cm ² on silk paper (Lenz cleaning).
paper "dasper (R)" Ozu Paper
r Co. Ltd.), and the temperature at which the image density reduction rate before and after the rubbing was less than 10% was set as the fixing temperature. The offset occurrence temperature is a temperature at which an offset appears visually when the temperature is increased.

<Developability / Filming Test> Using a commercially available copying machine NP-1010 (manufactured by Canon Inc.), 10,000 copies were continuously made and the developability (image density, fog) and on the photosensitive drum and developing sleeve were measured. Filming, fusion and the like were visually confirmed.

<Quantitative determination of residual monomer / solvent> C.
The peak area is determined by (gas chromatography) under the following conditions.

[G. C. Measurement conditions] Apparatus: GC-15A / with capillary (manufactured by Shimadzu Corporation) Carrier: N ₂ (2 kg / cm ² , 50 ml / min)
split (10 ml / 13 s) column: ULBON HR-1 50 m × 0.25 mm
(Made by Shinwa Kako)

[0095]

[Outside 2] Sample: 0.2 g of toner in THF (tetrahydrofuran)
Inject 2 μl from a solution obtained by dissolving in 4 ml. Standard substance: toluene Table 1 shows Examples 1 to 5 and Comparative Examples.

Examples 6 to 10 The toners of Examples 1 to 5 (toner 1 to 5
4) Commercially available copying machine FC-2 having surf fixing means
The fixability was good (density reduction rate was 10% or less) even at the first copy immediately after the power was turned on at an environmental temperature of 7.5 ° C. (manufactured by Canon Inc.). Immediately after copying 50 consecutive postcards at normal temperature, no offset due to a rise in the temperature of the non-sheet passing portion of the fixing device was observed even when copying was performed on A4 paper. Further, in the copying test, the developability was good, and no filming occurred without any problem.

[0097]

[Table 1]

[0098]

By using the specific binder resin obtained by the solution mixing method of the present invention and by setting the melt-kneading conditions of the kneader to a specific range, the toner components (wax, binder resin component) can be obtained. , And other materials), and a toner composition free from image deterioration such as fog can be provided. In addition, even if the fine coarse powder generated in the subsequent step (pulverization / classification) of the melt-kneading step is reused, there is no quality problem at all. The kneading conditions during kneading in the present invention do not require excessive shearing force due to dispersion, so that the molecular chain of the binder resin for toner can be suppressed, and the toner composition has excellent offset resistance, especially high-temperature offset resistance. Things can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a specific example of a surf fixing unit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 heating element 2 fixing film 3 drive roller 4 driven roller 5 pressure roller 6 transfer material 7 toner 8 entrance guide 9 resistance material 10 alumina substrate 11 detection element

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroaki Kawakami 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masaji Fujiwara 3-30-2 Shimomaruko, Ota-ku, Tokyo (72) Inventor Shinji Doi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-3-185458 (JP, A) JP-A-4-211271 ( JP, A) JP-A-3-86224 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03G 9/08

Claims (5)

(57) [Claims] 1. A weight average molecular weight (Mw) of 4000 to 5
0000, a resin (A) 50-9 having a ratio (Mw / Mn) of less than 3.5 between the weight average molecular weight and the number average molecular weight (Mn).
And 0 part by weight, the weight average molecular weight (Mw) of 400,000 or more resins (B) 50 to 10 parts by weight, and a further one or more waxes, and the solution mixed in the presence of a solvent (provided that the resin
When dissolving (B) in a solvent, wax coexists
) , A method for producing a composition for a toner, which comprises melting and kneading a binder resin produced by removing a solvent and another material. 2. The method according to claim 1, wherein the mixing of the solution is performed according to any of the following (1) to (4).
Line by any method selected from the group consisting of
The toner composition according to claim 1, wherein
Method of manufacturing a product. (1) A solution prepared by dissolving only wax in a solvent
(A) and resin (B) are added. (2) A solution prepared by dissolving only the resin (A) in a solvent
And the resin (B) are dissolved. (3) Add a solution containing only resin (A)
A solution in which the solution and the resin (B) are dissolved in a solvent is added. (4) Resin (A), resin (B) and wax in solvent
Dissolve at the same time. Wherein the temperature setting at the time of kneading the wax having a melting point of from 20 ° C. lower temperature or higher to 60 ° C. higher temperature or lower than the melting point of the wax, and claim 1, wherein the melt-kneading
3. The method for producing a toner composition according to item 2 . 4. The process for producing a toner composition according to any one of claims 1 to 3 melt-kneading while performing ventilation. 5. A weight average molecular weight (Mw) of 4000 to 5
0000, ratio of weight average molecular weight to number average molecular weight (Mn)
Resin (A) 50-9 having (Mw / Mn) less than 3.5
0 parts by weight and a weight average molecular weight (Mw) of 400,000 or less
50 to 10 parts by weight of the above resin (B) and one or more
And a solution in the presence of a solvent.
When dissolving (B) in a solvent, wax coexists
), Binder resin generated by solvent removal and other materials
Melt kneading, after cooling, pulverization, Characterized by classifying
Manufacturing method of toner.