JP2741607B2 - Toner for developing electrostatic images - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic image in electrophotography, electrostatic recording, electrostatic printing, and the like, and particularly to a hot roller fixing obtained by a pulverizing manufacturing method. It relates to a suitable electrostatic image developing toner.

[Prior Art] Conventionally, many electrophotographic methods are known as described in U.S. Pat. No. 2,297,601, Japanese Patent Publication No. 42-23910 and Japanese Patent Publication No. 43-24748. However, generally, using a photoconductive substance, an electric latent image is formed on the photoreceptor by various means, and then the latent image is developed using toner, and if necessary, transferred to a transfer material such as paper. After transferring the toner image, the toner image is fixed by heating, pressure, heating and pressurizing or solvent vapor to obtain a copy, and the toner remaining on the photoreceptor without being transferred is cleaned by various methods. The process is repeated.

In recent years, such copying apparatuses have begun to be used not only as office work copying machines for simply copying original documents, but also as printers as computer outputs or personal copiers for individuals.

As a result, smaller, lighter, faster, and more reliable devices are being sought after, and machines are becoming increasingly simpler in various respects. As a result, the performance required of the toner has become higher, and if the performance of the toner cannot be improved, a better machine cannot be realized.

For example, various methods and apparatuses have been developed for a process of fixing a toner image on a sheet such as paper, but the most common method at present is a pressure heating method using a heat roller.

The pressure heating method using a heating 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 at the time of fusing the toner image onto the sheet to be fixed is extremely good, and the fixing can be performed quickly. And is very effective in high speed electrophotographic copiers. However, in the above-mentioned method, since the surface of the heat roller and the toner image come into contact with each other under pressure in a molten state, a part of the toner image adheres and transfers to the surface of the fixing roller, and re-transfers to the next sheet to be fixed. An offset phenomenon may occur, and the sheet to be fixed may be stained. Preventing toner from adhering to the surface of the heat fixing roller is one of the essential conditions of the heat roller fixing method.

Conventionally, for the purpose of preventing toner from adhering to the surface of the fixing roller, for example, the roller surface is formed of a material having excellent releasability with respect to the toner, such as silicon rubber or a fluorine-based resin. In order to prevent fatigue, the roller surface is coated with a thin film of a liquid having good releasability such as silicone oil. However, this method is extremely effective in preventing toner offset, but has a problem that a fixing device is complicated because a device for supplying an anti-offset liquid is required. .

This is in the opposite direction to miniaturization and weight reduction, and moreover, silicon oil and the like may evaporate due to heat and contaminate the inside of the machine. Therefore, instead of using a silicon oil supply unit, instead of supplying the anti-offset liquid from the toner during heating, a method of adding a release agent such as low molecular weight polyethylene or low molecular weight polypropylene to the toner has been proposed. Have been. If a large amount of such an additive is added in order to obtain a sufficient effect, filming on a photoreceptor or contamination of the surface of a toner carrier such as a carrier or a sleeve will cause deterioration of an image and pose a practical problem. Therefore, a small amount of release agent is added to the toner so as not to deteriorate the image,
It has been practiced to use a device for supplying a small amount of releasing oil or cleaning the offset toner with a winding type device using a member such as a web.

However, in view of recent requirements for miniaturization, weight reduction, and high reliability, it is necessary and necessary to remove even these auxiliary devices, which is preferable. Therefore, it cannot be coped with without further improvement of the performance such as fixing and offset of the toner, and it is difficult to realize it without further improvement of the binder resin of the toner. As a technique for improving a binder resin of a toner, for example, Japanese Patent Publication No. 51-23354 discloses a toner using a crosslinked polymer as a binder resin. According to this method, the offset resistance and the anti-sticking property are effective, but the degree of cross-linking increases the fixing point, so that the fixing temperature is sufficiently low and the anti-offset property and anti-sticking property are good. No satisfactory fixing characteristics were obtained. In general, in order to improve the fixability, the binder resin must be reduced in molecular weight to lower the softening point, which is inconsistent with the offset resistance improvement treatment, and in order to reduce the softening point. Inevitably, the undesired phenomenon that the glass transition point of the resin is lowered and the toner during storage is blocked.

On the other hand, JP-A-58-187946 proposes a toner comprising a styrene-acryl copolymer and a polyester resin as resin components. The effect is to provide a developer that is excellent in productivity and excellent in offset with good image quality and transfer efficiency.However, in the case of heat kneading of polyester and styrene-acryl copolymer having different polarities, the resin It is difficult to obtain sufficient compatibility and uniformity, and as a result, it is difficult to satisfy both the fixing property and the offset property.

Similarly, Japanese Patent Application Laid-Open No. 63-127254 proposes a toner characterized by using a polyester resin and a styrene-methyl acrylate copolymer as resin components. Here, a resin is used in which the polyester has a weight average molecular weight Mw of 6,000 to 18,000, and the styrene-acrylic acid methyl ester copolymer has a Mw of 350,000. However, it is difficult to attain compatibility and uniformity in heat kneading of resins having different polarities as described above, and further, to achieve compatibility and uniformity in heat kneading of resins having extremely different molecular weights. Therefore, it is difficult to satisfy the fixing property and the offset property. In particular, the publication states that the weight average molecular weight (Mw) is preferably in the range of 200,000 to 500,000. However, when Mw is increased to further improve the anti-offset property, the fixing property and the pulverizability at the time of toner production are reduced. This is a practical problem, and it is therefore difficult to satisfy the offset resistance and the crushability with high performance. As described above, the toner having poor pulverizability at the time of toner production reduces production efficiency at the time of toner production,
Since coarse toner is apt to be mixed as a toner characteristic, a skipped image may be formed, which is not preferable.

As described above, it is extremely difficult to realize both the performance relating to fixing and the pulverizability with high performance. In particular, the pulverizability at the time of toner production is an important factor in today's direction to reduce the particle size of the toner due to the demand for high quality, high resolution and high fine line reproducibility of a copied image. Since the process requires a very large amount of energy, improvement of the pulverizability is important from the viewpoint of energy saving.

Also, the phenomenon of fusion of the toner to the inner wall of the pulverizing device is likely to occur in the toner having good fixing performance, and therefore, the pulverizing efficiency deteriorates. As another aspect, there is a step of cleaning the toner remaining on the photoconductor after the transfer in another copying step. Today, cleaning with a blade (blade cleaning) has become common in terms of miniaturization, weight reduction, and reliability of the apparatus. As the life of the photoconductor has been prolonged, the size of the photoconductor drum has been reduced, and the speed of the system has been increased, the anti-fusing and filming resistance to the photoconductor required for the toner have become severe. In particular, amorphous silicon photoconductors that have recently been put to practical use have extremely high durability, and the life of OPCs (organic photoconductors) has been prolonged. Therefore, various properties required for toners have become higher.

[Problems to be Solved by the Invention] An object of the present invention is to provide a toner which has solved the above-mentioned problems.

 The objects of the present invention are listed below.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner suitable for a hot roll fixing method without applying oil.

An object of the present invention is to provide a toner suitable for a cleaning method using a blade.

An object of the present invention is to provide a toner which can be fixed at a low temperature and has excellent offset resistance.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a toner which is fixed at a low temperature and does not cause fusing and filming to a photoreceptor even in a high-speed system or for a long time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner which can be fixed at a low temperature and has excellent blocking resistance, and which can be used sufficiently even in a high-temperature atmosphere in a small machine.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner that can be efficiently and continuously produced because the pulverized material is fixed at a low temperature and the pulverized material does not fuse to the inner wall of the apparatus in a pulverizing step in the production of the toner.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner which has excellent offset resistance and excellent pulverizability and thus has high production efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a toner capable of forming a stable and good developed image with less occurrence of coarse powder and the like due to good pulverizability, and hence less streaking around an image.

[Means and Actions for Solving the Problems] That is, the present invention relates to a toner for developing an electrostatic charge image having at least a binder resin and a colorant, wherein the THF-soluble portion of the binder resin has a molecular weight distribution based on GPC,
(A) at least one peak in the region of molecular weight 2000-7000
And a vinyl resin obtained by polymerizing one or more monomers selected from the group consisting of styrenes, acrylic acids, acrylic acid derivatives, methacrylic acids and methacrylic acid derivatives, and (b) a molecular weight of 7000 ~ 50,000
Having at least one peak or shoulder in the region, and comprising a polyester resin, wherein the binder resin is produced by polymerizing the polyester resin in the presence of the vinyl resin. The present invention relates to an electrostatic image developing toner.

 The present invention will be described in detail below.

In order to simultaneously achieve the above-mentioned objects, various binder resins were used, and the structure and performance of the resin were studied from various angles. As a result, in the molecular weight distribution of the THF-soluble component by GPC, styrenes and acrylic acids having at least one peak in a region of a molecular weight of 2,000 to 7000,
A binder that is uniformly compatible by polymerizing a polyester resin in the presence of a vinyl resin obtained by polymerizing one or more monomers selected from the group consisting of acrylic acid derivatives, methacrylic acids and methacrylic acid derivatives Are obtained, and as a result, the above-mentioned objects are simultaneously achieved.

The molecular weight distribution of the THF-soluble component and the property of whether the fixing temperature is high or low (hereinafter simply referred to as fixing property), the offset resistance, the pulverizability, and the blocking resistance were examined. And the function of components having a molecular weight of about 7000 or more differed. That is, the molecular weight 7000 to the entire binder resin
The content ratio of the component having the following molecular weight does not strongly influence the fixing property or the anti-offset property, as is usually said, but has little relation to the specific range in a specific range. Turned out to be related.

In addition, the polyester component having a molecular weight of 7000 or more mainly affects the offset resistance, the sticking property, and the fixing property.
It has been found that the following components mainly affect the pulverizability, the blocking property, the fusing property to the photoreceptor, the filming property, and the fusing to the inner wall of the pulverizing apparatus.

The proportion of the component having a molecular weight of 7000 or less is preferably from 10 to 50% by weight, and more preferably from 20 to 39% by weight. In order to obtain sufficient performance, the molecular weight is further 7000 or less, has a peak in the region of 2000 or more (preferably 2000 to 6000), and has a molecular weight of 7000 to 7000.
A peak or shoulder is required in the 50,000 (preferably 8000-40,000) region. No molecular weight between 2000 and 7000
There is a peak at 2000 or less, but if the proportion of the component having a molecular weight of 7000 or less is 50 wt% or more, there are some problems such as blocking resistance, fusion to a photoreceptor, filming, and fusion to the inner wall of a pulverizer. . There is no peak at a molecular weight of 7000 or less and a peak at 7000 or less.
% Or less, the pulverizability becomes a problem, and the generation of coarse particles also becomes a problem.

When there is no peak or shoulder in the region having a molecular weight of 7000 or more, and there is a peak only in the region having a molecular weight of 7000 or less, the offset resistance becomes a problem. If there is no peak or shoulder in the molecular weight region of 7000 to 50,000 and there is a main peak at 50,000 or more, pulverizability becomes a problem.

Furthermore, the THF-soluble component needs to satisfy Mw / Mn ≧ 5, and when Mw / Mn is 5 or less, the offset resistance tends to decrease, which is a problem. Preferably, Mw / Mn is 80 or less, and more preferably, 5 ≦ Mw / Mn ≦ 60. Especially Mw /
When Mn is 5 ≦ Mw / Mn ≦ 60, particularly excellent performance is exhibited in various characteristics such as pulverizability, fixing property, anti-offset property and image property.

Here, Mw is a weight average molecular weight measured by GPC described later, and Mn is a number average molecular weight obtained by the same measurement.

Further, the glass transition point Tg ₁ of the resin corresponding to the molecular weight distribution of the molecular weight distribution of THF-soluble component of 7000 or less and the glass transition point Tg _{t of the} whole toner.
When comparing Tg ₁ ≧ Tg _t -5, the fixing property is
The pulverizability, fusing to the photoreceptor, filming, fusing to the inner wall of the pulverizer, and blocking resistance are improved.

Here, Tg ₁ is measured by the following method. At a temperature of 25 ° C., THF is flowed at a flow rate of 7 ml per minute, and a THF sample solution having a concentration of about 3 mg / ml of a THF-soluble component of the toner is injected into a molecular weight distribution measuring device of about 3 ml, and components having a molecular weight of 10,000 or less are introduced. To separate. After fractionation, the solvent was distilled off under reduced pressure and further 90 ° C.
Dry for 24 hours under reduced pressure in an atmosphere. The above operation is repeated until about 20 mg of a component having a molecular weight of 10,000 or less is obtained.
In perform annealing for 48 hours, the Tg was measured by differential scanning calorimetry after this, this value and Tg _1.

TSKgel G2000H, TSKgel G2500H,
TSKgel G3000H, TSKgel G4000H (Toyo Soda Kogyo Co., Ltd. and the like are used, but TSKgel G2000H and TSKgel G2000H are used in the present invention.
SKgel G3000H was used in combination.

The values of Tg _t is a Tg of the toner 50 ° C. The toner was annealed for 48 hours, determined by the subsequent differential scanning calorimetry.

In the present invention, the molecular weight of a peak or / and a shoulder of a chromatogram by GPC (gel permeation chromatography) is measured under the following conditions.

That is, the column was stabilized in a heat chamber at 40 ° C., and THF (tetrahydrofuran) was passed through the column at this temperature as a solvent at a flow rate of 1 ml per minute, and a THF sample of a resin adjusted to a sample concentration of 0.05 to 0.6% by weight was used. The solution
Measure by injecting 50-200μ. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count number. As a standard polystyrene sample for preparing a calibration curve, for example, Pressure Chemical C
o. or Toyo Soda Kogyo Co., Ltd. with a molecular weight of 6 × 10 ² , 2.1
× 10 ³ , 4 × 10 ³ , 1.75 × 10 ⁴ , 5.1 × 10 ⁴ , 1.1 × 10 ⁵ , 3.9 × 10 ⁵ ,
Use 8.6 × 10 ⁵ , 2 × 10 ⁶ , 4.48 × 10 ⁶ and at least 1
It is appropriate to use about 0 standard polystyrene samples. An RI (refractive index) detector is used as the detector.

In order to accurately measure the molecular weight region of 10 ³ to 2 × 10 ^6, a plurality of commercially available polystyrene gel columns are preferably used. For example, μ-styr manufactured by Waters, Inc.
agel 500,10 ³ , 10 ⁴ , 10 ⁵ combination or Showa Denko
shodex KF-80M or a combination of KF-802,803,804,805 or TSKgel G1000H, G2000H, G2500H, G300 manufactured by Toyo Soda
A combination of 0H, G4000H, G5000H, G6000H, G7000H, and GMH is preferred.

The weight% based on the binder resin having a molecular weight of 7000 or less according to the present invention is obtained by cutting out the molecular weight of 7000 or less in the chromatogram by GPC, calculating the weight ratio with the cutout having the molecular weight of 7000 or more, and calculating the weight% based on the entire binder resin.

The resin composition having a molecular weight of 7000 or less in the toner of the present invention is obtained by polymerizing one or more monomers selected from styrenes, acrylic acids, methacrylic acids and derivatives thereof from a vinyl-based resin in view of development characteristics and charging characteristics. preferable. Examples of monomers that can be used include styrenes such as styrene, α-methylstyrene, vinyltoluene,
Chlorstyrene and the like. Examples of acrylic acids, methacrylic acids and derivatives thereof include acrylic acid, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, n-tetradecyl acrylate,
Acrylates such as n-hexadecyl acrylate, lauryl acrylate, cyclohexyl acrylate, dimethylaminoethyl acrylate, dimethylaminoethyl acrylate, and the like can also be mentioned. Similarly, methacrylic acid, methyl methacrylate, ethyl methacrylate, methacrylic acid Propyl, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate,
Octyl methacrylate, decyl methacrylate, dodecyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, methacrylic acid 2
Methacrylates such as -hydroxyethyl, 2-hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, glycidyl methacrylate, and stearyl methacrylate. In addition to the aforementioned monomers,
A small amount of other monomers as long as the object of the present invention can be achieved,
For example, acrylonitrile, 2-vinylpyridine, 4-vinylpyridine, vinylcarbazole, vinylmethylether, butadiene, isoprene, maleic anhydride, maleic acid, maleic monoesters, maleic diesters, and vinyl acetate may be used. good.

As a polyester resin having a molecular weight of 7000 or more, in addition to etherified diphenols, a well-known softening point is 60 to 130 ° C.
Those in the range are preferably used. For example, a polyester comprising an aromatic dicarboxylic acid and an aliphatic glycol,
Or aliphatic dicarboxylic acids and etherified diphenols,
Alternatively, in bis-based polyesters based on etherified diphenols, when an aromatic acid is used as the acid component as a main component, the offset is remarkably improved during non-linearization, and A heat-fixable dry toner that effectively prevents the increase in the fixing point due to non-linearity and the deterioration in moisture resistance by introducing specific alkyl-substituted dicarboxylic acids and / or alkyl-substituted diols into the basic skeleton as soft segments. Is provided.

The reason for this is that the present inventors speculated that the soft segment introduced into the polymer skeleton has the effect of loosening the network skeleton, effectively lowering the fixing point, further increasing the degree of freedom of the functional group to some extent, and reducing the COOH of the residue. It is thought that the moisture resistance is improved by reducing the number of OH groups. In addition, the C ₅ -C ₁₈ alkyl group as a soft segment is not incorporated into the main chain, but is introduced into the main chain in a planch manner, so that the toughness of the resin itself is not impaired. In other words, when incorporated into the main chain, it becomes similar to a linear polyester, and although the fixing point is lowered, the resin becomes brittle, and even when melted, the viscous properties become stronger and the offset resistance can be deteriorated There is.

Examples of the soft segment component used in the polyester of the present invention include maleic acid, fumaric acid, glutaric acid, succinic acid, malonic acid, adipic acid, sebacic acid, azelaic acid and the like having an alkyl substituent (preferably C _{5 to} C ₁₈ ). Saturated or unsaturated aliphatic dicarboxylic acids such as anhydrides and esterified products thereof, and ethylene glycol, 1,3-propylene diol, tetramethyl glycol, 1 having an alkyl substituent (preferably C _{5 to} C ₁₈ ) Saturation of 1,4-butylene diol, 1,5-pentyldiol, 1,5-pentylene glycol, pentamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol or the like Unsaturated aliphatic glycols include Can be

These soft segment components need to be contained in the polyester in an amount of 10 to 25% by weight, and more preferably 15 to 20% by weight. If it is less than 10% by weight, it is difficult to lower the fixing temperature effectively.
If it is 25% by weight or more, the tendency to block during storage increases.

As the non-linear component, aromatic or other trivalent or higher polycarboxylic acids such as trimellitic acid, pyromellitic acid, cyclohexanetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4 -Naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5
-Hexanetricarboxylic acid, 1,3-dicarboxyl-2-
Methylenecarboxylpropane, 1,3-dicarboxyl-
2-Methyl-2-methylenecarboxylpropane, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid and their anhydrides can be used. Further, a trivalent or higher polyol may be added. For example, sorbitol, 1,2,3,6-hexanetetol, 1,4-sorbitan, pentaerythritol, dipentaerythritol,
Tripentaerythritol, sucrose, 1,2,4-mesitatriol, glycerin, 2-methylpropanetriol, 2-
Methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene and the like can be used. These non-linear components are preferably contained in the polyester in an amount of 10 to 30% by weight as a polycarboxylic acid, and the polyols are preferably contained in an amount of 5% by weight or less. 30% by weight of polycarboxylic acid
When the content is more than 5% by weight or more, the moisture resistance deteriorates and the charging characteristics become unstable. Conversely, if the total amount of the polycarboxylic acid polyol is less than 10% by weight, the non-linearity is insufficient and the offset resistance tends to deteriorate.

Further, as the main acid component of the polyester of the present invention, there are aromatic dicarboxylic acids or similar anhydrides, and other dicarboxylic acids. However, in order to impart sufficient chargeability in terms of electrophotographic properties, 50 mol% of the total acid components is used. It is necessary that at least 60 mol% of aromatic dicarboxylic acids be aromatic dicarboxylic acids. As aromatic dicarboxylic acids, terephthalic acid, isophthalic acid, phthalic acid, diphenyl-
P, P'-dicarboxylic acid, naphthalene-2,7-dicarboxylic acid, naphthalene-2,6-dicarboxylic acid, diphenylmethane-P, P'-dicarboxylic acid, benzophenone-4,4'-dicarboxylic acid, 1,2- Diphenocietan-P, P'-dicarboxylic acid and the like can be used, and as other acids, maleic acid, fumaric acid, glutaric acid, cyclohexanecarboxylic acid, succinic acid, malonic acid, adipic acid and the like can be used.

Further, the etherified diphenols as main components are preferably ethoxylated or propoxylated etherified diphenols.

The polyester used in the present invention has an acid value of 10 to 60, preferably 20 to 50. If the acid value is less than 10, the non-linearity proceeds too much to increase the fixing point, and if it exceeds 60, the moisture resistance deteriorates.

The method for synthesizing the binder resin according to the present invention is basically preferably a method for synthesizing two or more polymers. That is, this is a method for obtaining a polyester resin in the presence of a vinyl resin soluble in THF. In this case, a composition is formed in which the former and the latter polymers are uniformly mixed.

The vinyl resin which is soluble in THF is preferably solution polymerization or ionic polymerization. Particularly, solution polymerization in the presence of a solvent forms a homogeneous mixture with the next monomer for polyester to be polymerized by the action of the solvent. This is preferable since a composition obtained by uniformly mixing is formed.

As the solvent used in the solution polymerization, xylene, toluene, cumene, cellosolve acetate, isopropyl alcohol, benzene and the like are used. In the case of a styrene monomer, xylene, toluene or cumene is preferred. It is appropriately selected depending on the polymer to be polymerized. The initiator is di-tert-butyl peroxide, tert-butyl peroxybenzoate, benzoyl peroxide, 2,2
0.1 parts by weight or more (preferably 0.4 to 15 parts by weight) of 2'-azobisisobutyronitrile, 2,2'-azobis (2,4-ditylvaleronitrile), etc., based on 100 parts by weight of the monomer
Used at a concentration of The reaction temperature varies depending on the solvent used, the initiator, and the polymer to be polymerized.
It is good to carry out at ~ 180 ℃. Solvent 1 in solvent polymerization
It is preferable to use 30 parts by weight to 400 parts by weight of the monomer with respect to 100 parts by weight.

In the toner using the resin of the present invention, in addition to the above-mentioned binder resin component, the following compound is contained in a proportion smaller than the content of the binder resin component, as long as the effect of the present invention is not adversely affected. You may.

For example, silicone resin, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral, rosin, modified rosin, terpene resin, phenolic resin, aliphatic or alicyclic hydrocarbon resin such as low molecular weight polyethylene or low molecular weight polypropylene, aromatic type Petroleum resin, chlorinated paraffin, paraffin wax and the like.

As the charge control unit used in the toner of the present invention, a conventionally known positive or negative charge control agent is used. today,
The charge control agents known in the art include the following.

(1) The following substances control the toner to be positively charged.

Nigrosine, an azine dye containing an alkyl group having 2 to 16 carbon atoms (Japanese Patent Publication No. 42-1627), a basic dye (for example, CI
Basic Yellow 2 (CI41000), CIBasic Yellow 3,
CIBasic Red 1 (CI45160), CIBasic Red 9 (C.
I.42500), CIBasic Violet 1 (CI42535), CIBa
sic Vioet 3 (CI42555), CIBasic Violet 10 (C.
I.45170), CIBasic Violet 14 (CI42510), CIB
asic Blue 1 (CI42025), CIBasic Blue 3 (CI51
005), CIBasic Blue 5 (CI42140), CIBasic Bl
ue 7 (CI42595), CIBasic Blue 9 (CI52015),
CIBasic Blue 24 (CI52030), CIBasic Blue 25
(CI52025), CIBasic Blue 26 (CI44025), C.I.
I.Basic Green 1 (CI42040), CIBasic Green 4
(CI42000) and other lake pigments of these basic dyes. ), CISolvent Black 3 (CI2615
0), Hansa Yellow G (CI11680), CIMordlant B
lack 11, CIPigment Black 1 etc.

Or, for example, benzolmethyl-hexadecylammonium chloride, decyl-trimethylammonium chloride, dialkyltin compounds such as dibutyl and dioctyl, metal salts of higher fatty acids, inorganic fine powders such as glass, mica, zinc oxide, and metal complexes of EDTA and acetylacetone. And polyamine resins such as amino group-containing vinyl polymers and amino group-containing condensation polymers. From the viewpoint of dispersibility in particular, Nigrosine, metal salts of higher fatty acids,
Vinyl polymers having an amino group are preferred.

(2) The following substances control toner load. JP-B-41-20153, JP-B-42-27596, JP-B-44-63
And metal complex salts of monoazo dyes described in JP-A Nos. 97 and 45-26478.

Nitrohumic acid and its salts or dyes and pigments such as CI14645 described in JP-A-50-133338,
No. 2752, JP-B-58-41508, JP-B-58-7384, and JP-B-59-7384, etc., metals such as salicylic acid, naphthoic acid and dicarboxylic acid such as Zn, Al, Co, Cr and Fe Complex,
Sulfonated copper phthalocyanine pigment, styrene oligomer into which nitrile group and halogen are introduced, chlorinated paraffin and the like. In particular, from the viewpoint of dispersibility, a metal complex salt of a monoazo dye, and a metal complex of salicylic acid, alkyl salicylic acid, naphthoic acid, and dicarboxylic acid are preferable.

The toner of the present invention can provide good results even when additives are mixed as necessary. As the additive, for example, a lubricant such as Teflon, zinc stearate, and polyvinylidene fluoride is preferable, and polyvinylidene fluoride is particularly 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. An anti-caking agent, a conductivity-imparting agent such as carbon black, zinc oxide, antimony oxide, and tin oxide; a fixing aid such as low-molecular-weight polyethylene, low-molecular-weight polypropylene, and various waxes; Further, a small amount of white fine particles and black fine particles of opposite polarity can be used as a developing property improver.

Further, 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 of the toner and the carrier powder is 0.1 to 50% by weight, preferably 0.5 to 10% by weight, and more preferably 3 to 5% by weight as the toner concentration.

As the carrier that can be used 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 silicon resin And the like surface-treated.

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;
Metals such as iron, cobalt, nickel or the metals aluminum, cobalt, copper, lead, magnesium,
Examples include alloys of metals such as tin, zinc, antimony, beryllium, bismuth, cadmium, calcium, manganese, selenium, titanium, tungsten, and vanadium, and mixtures thereof.

These ferromagnetic materials preferably have an average particle size of about 0.1 to 2 μm, preferably about 0.1 to 0.5 μm, and particularly preferably have a spherical shape. The amount contained in the toner is preferably about 20 to 200 parts by weight, particularly preferably 40 to 180 parts by weight, per 100 parts by weight of the resin component.

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

As the colorant used in the toner of the invention, any suitable pigment or dye is used. Toner colorants are well known and include pigments such as carbon black, aniline black, acetylene black, naphthol yellow, hansa yellow, rhodamine lake, alizarin lake, bengalara, phthalocyanine blue, and indanthrene blue. These are used in an amount necessary and sufficient to maintain the optical density of the fixed image, and 0.1 to 20 parts by weight, preferably 2 to 10 parts by weight, per 100 parts by weight of the resin is good. A dye is further used for the same purpose. For example, there are azo dyes, anthraquinone dyes, xanthene dyes, methine dyes, etc.
An addition amount of 20 parts by weight, preferably 0.3 to 3 parts by weight is good.

To prepare the electrostatic image developing toner according to the present invention, the resin composition according to the present invention, a charge control agent, a magnetic material and a pigment or dye as a colorant, if necessary, an additive, etc. are added to a ball mill or the like. After thoroughly mixing with a mixer, the mixture is melted, kneaded and kneaded using a hot kneader such as a heating roll, kneader, extruder or the like to disperse or disperse the pigment or dye while the resins are mutually compatible. After cooling and solidification, the resulting mixture is pulverized and classified to obtain a toner having an average particle size of 3 to 20 μm.

[Examples] Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto. The parts in the following formulations are parts by weight.

Synthesis Example 1 200 parts of cumene was placed in a reactor and heated to a reflux temperature. A mixture of 100 parts of styrene monomer and 8 parts of di-tert-butyl peroxide was added dropwise thereto over 4 hours under reflux of cumene. Further under cumene reflux (146 ° C to 156 ° C)
Completed the solution polymerization. The obtained polystyrene was soluble in THF, Mw = 3,700, Mw / Mn = 2.64, the molecular weight at which the main peak of GPC was located was 3,500, and Tg = 57 ° C.

Next, a cumene solution corresponding to 30 parts of the polystyrene resin was added to 32.5 parts of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane and 2.50 parts of sorbitol.
0 parts and 3.1 parts of ethylene glycol having an alkyl substituent having 8 carbon atoms were mixed to prepare a mixed solution, which was then mixed with a thermometer, a stirrer, a glass inlet tube, and a four-necked circle equipped with a flow-down coagulator. Placed in bottom flask. Nitrogen gas was introduced through a glass introduction tube to stir the polymer blend, and the inside of the reaction vessel was made an inert atmosphere.

Then, the mixture was heated to 50 ° C. while continuing stirring, and 15 parts of terephthalic acid, 7.6 parts of trimellitic acid, and 7.8 parts of malonic acid having an alkyl substituent having 8 carbon atoms were added to the reaction vessel.
After the reaction at 5 ° C. for 5 hours, the pressure was gradually reduced and the reaction was carried out at about 100 mmHg. When the softening point of the resin reached 100 ° C., the reaction was completed. The acid value was 25.0. When the molecular weight distribution of the THF-soluble component was measured, it was found to have peaks at about 0.40 and about 88,000 in the GPC chart, and the Tg of the resin was 60 ° C.

The properties relating to the molecular weight of each resin and the resin composition were measured by the following methods.

Using Shodex KF-80M as a column for GPC measurement, it was incorporated into a 40 ° C heat chamber of a GPC measurement device (Waters 150CALC / GPC) at a THF flow rate of 1 ml / min. Concentration of about 0.1% by weight)
GPC was measured by injection. As a calibration curve for molecular weight measurement, the molecular weight is 0.5 × 10 ³ , 2.35 × 10 ³ , 10.2 × 10 ³ , 35 × 1
0 ³ , 110 × 10 ³ , 200 × 10 ³ , 470 × 10 ³ , 1200 × 10 ³ , 2700 × 10 ³ ,
A THF solution of 10 points of 8420 × 10 ³ monodisperse polystyrene reference substances (manufactured by Waters) was used.

Synthesis Example 2 150 parts of cumene was placed in a reactor and heated to a reflux temperature. The following mixture was added dropwise over 4 hours under cumene reflux.

Further, the polymerization was completed under quenching reflux (146 to 156 ° C). The obtained styrene-n-butyl acrylate copolymer had a main peak at the position of Mw = 6,900, Mw / Mn = 2.3, molecular weight 6,000, and had Tg = 60 ° C.

40 parts of the above styrene-n-butyl acrylate copolymer was mixed with 33.8 parts of polyoxyethylene (2,2) -2,2-bis (4-hydroxyphenyl) propane and 0.8 parts of glycerin.
And 3.3 parts of 1,3 propylene glycol having an alkyl substituent having 10 carbon atoms, and placed in a reaction vessel in the same manner as in Synthesis Example 1 to obtain an inert atmosphere.

Then heating while continuing stirring, terephthalic acid 13.3
Parts, 10.2 parts of pyromellitic acid, and 9.2 parts of succinic acid having an alkyl substituent having 10 carbon atoms were added to the reaction vessel, and the mixture was added at 210 ° C for 5 minutes.
After the reaction, the pressure was gradually reduced and the reaction was carried out at about 100 mmHg. The reaction was terminated when the softening point of the resin reached 95 ° C. Acid value 35.5
Met. When the molecular weight distribution of the THF-soluble component was measured, G
In the chart of PC, there were peaks at positions of about 60000 and about 88,000, and the Tg of the resin was 59 ° C.

Synthesis Example 3 200 parts of cumene was charged into a reactor and heated to a reflux temperature. The following mixture was added dropwise over 4 hours under cumene reflux.

Further, the polymerization was completed under quenching reflux (146 to 156 ° C). The obtained polystyrene had Mw = 3,700 and Mw / Mn = 2.6.
4. It had a main peak at a molecular weight of 3,500 and had a Tg of 57 ° C. 30 parts of the above polystyrene was dissolved in the following monomer mixture to give a mixture.

The acid value of the resin was 20 in the same manner as in Synthesis Example 1 except that the amount of malonic acid having an alkyl substituent having 8 carbon atoms was changed to 648 g and the amount of ethylene glycol having an alkyl substituent having 8 carbon atoms was changed to 532 g. When the reaction has finished.

When the molecular weight distribution of the THF-soluble component was measured, it had peaks at about 0.35 million and about 88,000 in the GPC chart, and the Tg of the resin was 50 ° C.

Comparative Synthesis Example 1 200 parts of cumene was placed in a reactor and heated to a reflux temperature. A mixture of 100 parts of styrene monomer and 8 parts of di-tert-butyl peroxide was added dropwise thereto over 4 hours under reflux of cumene. The solution polymerization was completed under cumene reflux (146 to 156 ° C). The obtained polystyrene was soluble in THF, Mw = 3,700, Mw / Mn = 2.64, the molecular weight at which the main peak of GPC was located was 3,500, and Tg = 57 ° C.

 30 parts of the above resin were prepared.

32.5 parts of polyoxypropylene (2,2) -2,2-bis (4-hydroxyphenyl) propane and sorbitol 2.0
Parts, 3.1 parts of ethylene glycol having an alkyl substituent having 8 carbon atoms was placed in a four-necked round-bottomed flask equipped with a thermometer, a stirrer, a glass inlet tube, and a falling aggregator. Nitrogen gas was introduced through a glass introduction tube to stir the polymer blend, and the inside of the reaction vessel was made an inert atmosphere.

Then, the mixture was heated to 50 ° C. while continuing stirring, and 15 parts of terephthalic acid, 7.6 parts of trimellitic acid, and 7.8 parts of malonic acid having an alkyl substituent having 8 carbon atoms were added to the reaction vessel.
After the reaction at 5 ° C. for 5 hours, the pressure was gradually reduced and the reaction was carried out at about 100 mmHg. When the softening point of the resin reached 100 ° C., the reaction was completed. The acid value was 25.0. When the molecular weight distribution of the THF-soluble component was measured, it had a peak at a position of about 88,000 in the GPC chart, and the Tg of the resin was 62 ° C.

 70 parts of the above resin were prepared.

Example 1 After pre-mixing the above ingredients with a Henschel mixer,
The mixture was kneaded with a two-roll mill heated to 20 ° C for 20 minutes. After allowing the kneaded material to cool, coarsely pulverized with a cutter mill, pulverized using a fine pulverizer using a jet stream, and further classified using an air classifier, a black fine powder having a volume average particle size of 11.5 μm was obtained. Obtained.

Colloidal silica fine powder for 100 parts of the black fine powder
0.4 parts were dry-fitted to obtain a developer (toner).

The pulverizability at the time of the production of the toner can be represented by the throughput of the pulverizable toner per unit time. In the case of this toner, the pneumatic pressure was 5.5 kg / cm ^{2 and} was 15 kg / hr, which was very good. No fusion occurred in the crusher.

Further, the blocking property was examined by a change in agglomeration when about 10 g of the toner was put in a 100 cc polycup and left at 50 ° C. for one day. The degree of aggregation was measured with a powder tester manufactured by Hosokawa Micron. At room temperature and at 50 ℃ for 1 day
The values were almost the same at 10% by weight and 12% by weight, and since the difference (ΔG) was 2%, it was confirmed that there was substantially no blocking.

For fixing and offset properties, wrapping property and image quality, and durability, Canon high-speed copier, NP-8570 (7 minutes per minute)
0V, 100V).

In particular, for the offset property, the cleaning mechanism of the fixing roller was removed, and the number of copies of the image or the stain of the roller was evaluated based on the number of copies to be resisted.

The test was conducted by lowering the set temperature of the fixing device by 5 ° C. The fixability is
The image was rubbed with Silbon C paper 10 times in a reciprocating manner at a load of about 100 g, and the peeling of the image was represented by a reduction rate (%) of the reflection density. The evaluation image was viewed at the 200th sheet when 200 sheets were continuously taken.

The wrapping property was determined by taking out three images of the entire surface of a black image, and at that time, the state of the nails for peeling off the fixing roller on the image, and how much the nails depended.

As a result, the fixing property was very good with a reduction rate of 3%, the offset property was a good port with no dirt on the rollers even on 50,000 sheets, and the wrapping property showed a slight trace depending on the claws on the image. It was good.

A durability test was performed on about 50,000 sheets using an image having an image area ratio of about 5%. The image was good, and there was no fusion or filming to a photosensitive member or the like.

Comparative Example 1 In place of the resin composition of Example 1, the resin composition prepared in Comparative Synthesis Example 1 (30 parts of polystyrene and polyester 70)
And a toner (Comparative Example 1) was prepared in the same manner as in Example 1.

Evaluation of the toner of the comparative example was performed in the same manner as in Example 1, and the results are shown in Table 1.

Example 2 A toner was prepared from the above mixture in the same manner as in Example 1. The volume average particle size was 11.7 μm.

As the colloidal silica fine powder, one treated with amino-modified silicone oil was used.

The pulverizability of the toner was very good at a throughput of 16 kg / hr. There was no fusion in the crusher. The blocking property was not a problem at all at ΔG = 3%.

The image quality and fixing relationship were also evaluated using a Canon personal copying machine FC-5.

As a result, the image was good and a good image was continuously produced until the toner was exhausted, and there was no filming or fusion to the photosensitive member.

Further, the set temperature of the fixing unit was lowered by 10 ° C., and the cleaning mechanism of the fixing unit was removed, and the above-described image was produced. The fixing property was very good with a decrease rate of about 0%.
There was no problem with the winding property.

Example 3 A toner was prepared in the same manner except that the resin composition of Example 2 was changed to the resin composition of Synthesis Example 3.

 The volume average particle size of the toner was 11.3 μm.

The pulverizability of the toner was very good at a processing amount of 15.5 kg / hr. There was no fusion in the crusher.

The blocking property was no problem at all when ΔG = 2%.

The image quality and the fixing relationship were evaluated using a Canon NP-5540 copier (OPC photoreceptor, every 40 minutes).

As a result, the image was good and a stable image was obtained although 50,000 sheets were durable. Also, filming on photoreceptor,
There was no fusion.

In addition, the set temperature of the fixing unit was lowered by 10 ° C., and the cleaning mechanism of the fixing unit was removed to perform the above-mentioned durability. Was.

[Effects of the Invention] The present invention provides offset resistance, winding property, fixing property, pulverizability, blocking property, and photoreceptor by using a mixed composition of polymers having peaks in specific different molecular weight ranges as a binder resin. It has excellent adhesion to film and filming property.

Claims (3)

(57) [Claims] 1. A toner for developing an electrostatic charge image having at least a binder resin and a colorant, wherein in a molecular weight distribution of a THF-soluble portion of the binder resin by GPC, (a) a peak is present in a region of a molecular weight of 2,000 to 7000. Have at least one,
And a vinyl resin obtained by polymerizing one or more monomers selected from the group consisting of styrenes, acrylic acids, acrylic acid derivatives, methacrylic acids and methacrylic acid derivatives, and (b) a region having a molecular weight of 7000 to 50,000. Having at least one peak or shoulder, and comprising a polyester resin, wherein the binder resin is produced by polymerizing the polyester resin in the presence of the vinyl resin. Image developing toner. 2. The electrostatic image developing toner according to claim 1, wherein the binder resin has at least a peak in a molecular weight region of 2,000 to 7,000 and a peak in a molecular weight region of 7,000 to 50,000. 3. The toner according to claim 1, wherein the vinyl resin is produced by a solution polymerization method, and the polyester resin is produced in the presence of a solvent of the solution polymerization method. .