JP5818573B2 - toner - Google Patents

Description

  The present invention relates to an electrophotographic image forming method and a toner used in a toner jet method.

  In recent years, image forming apparatuses such as electrophotographic apparatuses have been required to be reduced in size and weight, and on the other hand, high speed and high durability have been strictly pursued. Further, the image forming apparatus is used for applications such as copying of high-definition images such as graphic design, and light printing that requires higher reliability and higher productivity.

  When an image forming apparatus is used for light printing applications, it is important that the image quality does not change regardless of the number of printed sheets. In this case, the characteristics required of the toner include that the chargeability does not change depending on the usage environment, time, and usage status of the user.

  Conventionally, various materials have been studied in order to control the charging characteristics of the toner. Patent Document 1 proposes to stabilize the chargeability by externally adding magnetic powder. However, the method of controlling the charging by the external additive tends to liberate the external additive and easily causes image defects. In particular, in a developing device for light printing, when a stirring member or the like in a developing device rotates at high speed, free magnetic powder is easily generated and image defects are easily generated.

  On the other hand, improvement of the charging characteristics of the toner particles themselves has also been studied. Patent Document 2 describes that by controlling the molecular weight and softening point of a charge control resin, which is a styrene monomer, and using it in a toner, excellent development characteristics can be obtained regardless of the environment. However, in such toner, in the toner particles, there are a part where the charge control agent exists as a domain and a part where the charge control agent and the binder resin are compatible at the molecular level. The charging characteristics are different between the two. As a result, particularly when printing a large number of sheets, the small charge difference may lead to a decrease in image density in the second half of the durability, and there is still room for improvement.

  Further, conventionally known organic salts and complexes containing a divalent or higher metal are generally low molecular weight compounds, so that the dispersion diameter is too small, and there are problems such as a decrease in chargeability due to aggregation.

  An example of a material that does not become compatible with the binder resin and is finely dispersed in the toner is wax. Patent Documents 3 to 5 describe controlling the melting point and molecular weight of the wax and performing acid modification in order to finely disperse the wax in the toner. However, although such a wax has an effect as a fixing aid or a release agent, it does not function as a material for improving the charging characteristics of the toner.

JP-A-7-230182 JP 2002-189317 A Japanese Patent Application Laid-Open No. 08-82954 Japanese Patent Laid-Open No. 06-93026 JP 2000-352838 A

  An object of the present invention is to provide a toner that solves the above problems. That is, an object of the present invention is to provide a toner that has good chargeability regardless of the usage environment, time, and user usage status, and can suppress fluctuations in image density even when used for a long time. is there.

The present invention is a toner having toner particles containing a binder resin and a colorant, wherein the binder resin has an acid value (Avr) of 1 mgKOH / g or more and 40 mgKOH / g or less. Containing an acid-modified polyolefin resin, the acid-modified polyolefin resin,
(1) Acid value (Avp) is 10 mgKOH / g or more and 50 mgKOH / g or less,
(2) The peak temperature of the maximum endothermic peak at the time of temperature rise in the DSC curve measured by a differential scanning calorimeter is 60 ° C. or higher and 95 ° C. or lower,
(3) The toner is characterized in that the peak molecular weight (Mpp) of the ortho-dichlorobenzene-soluble component of the acid-modified polyolefin resin, measured by gel permeation chromatography, is 10,000 or more and 100,000 or less.

  According to the present invention, it is possible to obtain a toner that has good chargeability regardless of the use environment, time, and user's use condition and can suppress image density fluctuation even when used for a long period of time.

  The present inventors have found that by using an acid-modified polyolefin resin having the following properties in the toner, a toner having good chargeability can be obtained regardless of the usage environment, time, and user usage. . The acid-modified polyolefin resin refers to a resin in which a polyolefin moiety and a monomer moiety having an acid value are chemically bonded.

  The acid value (Avp) of the acid-modified polyolefin resin used in the present invention is 10 mgKOH / g or more and 50 mgKOH / g or less. In the acid-modified polyolefin resin, the monomer part having an acid value bonded to the polyolefin part contributes to the charging property. When the Avp is within the above range, the amount of the monomer part having an acid value bonded to the polyolefin part is suitable, so that the acid-modified polyolefin resin has suitable chargeability. In addition, since the acid-modified polyolefin resins repel each other electrostatically, aggregation is suppressed and the acid-modified polyolefin resins are easily dispersed in the toner particles. The acid value of the acid-modified polyolefin resin is more preferably 20 mgKOH / g or more and 40 mgKOH / g or less.

  When Avp is less than 10 mgKOH / g, the dispersibility of the acid-modified polyolefin resin is deteriorated and sufficient chargeability cannot be obtained, and the rising of the charge of the toner after being left is deteriorated. In particular, this tendency is remarkable in a high-temperature and high-humidity environment where the fluidity of the toner tends to decrease. Moreover, when larger than Avp50mgKOH / g, the charge property of acid-modified polyolefin resin becomes too high. As a result, the variation in image density between print jobs increases. Note that fluctuations in image density between print jobs are considered to occur by the following mechanism. When the chargeability of the toner is too high, the toner is charged up as the image is continuously output, so that it is difficult for the toner to fly from the developer carrying member to the photosensitive member, and the image density is lowered. However, when the print job ends and a certain time elapses, toner charging is eased. Therefore, when printing is resumed, the image density temporarily increases. This increases the variation in image density between print jobs. In particular, in light printing applications, since image quality stability is required, such fluctuations in image density between print jobs are undesirable.

  The acid value (Avr) of the binder resin used in the present invention is 1 mgKOH / g or more and 40 mgKOH / g or less. As described above, the acid-modified polyolefin resin used in the present invention has a certain acid value or more. Therefore, when there is almost no acid value of binder resin, acid-modified polyolefin resin is hard to disperse | distribute in binder resin, and will segregate. On the other hand, if Avr is within the above range, the polarity of the acid-modified polyolefin resin and the polarity of the binder resin are close to some extent, so that the acid-modified polyolefin resin is prevented from segregating in the binder resin. Accordingly, the dispersibility of the acid-modified polyolefin resin between the toner particles can be further improved, the charging stability of the toner can be improved, and more stable development performance can be obtained.

  When Avr is less than 1 mgKOH / g, a portion where the acid-modified polyolefin resin is partially segregated in the toner appears. Such a toner often has a wide charge distribution, and thus the image density tends to fluctuate. On the other hand, when Avr is larger than 40 mgKOH / g, the negative chargeability of the binder resin becomes strong, and the density fluctuation between print jobs accompanying the toner charge-up becomes large. Avr is preferably 10 mgKOH / g or more and 37 mgKOH / g or less, and more preferably 20 mgKOH / g or more and 35 mgKOH / g or less.

  The acid-modified polyolefin resin used in the present invention has a peak molecular weight (Mpp) of the ortho-dichlorobenzene-soluble component of the acid-modified polyolefin resin as measured by gel permeation chromatography (GPC) of 10,000 to 100,000. If the range of Mpp is within the above range, the charging stability of the toner can be improved, and initial and late density fluctuations (long-term density fluctuations) in durable printing can be suppressed. The reason is considered as follows. Conventional charge control agents such as metal complexes are very small molecules due to their low molecular weight. As a result, the charge control agent itself exists as an aggregate. Even if this is to be dispersed in the toner, it is difficult to uniformly disperse it in the toner by dividing it into a finely dispersed portion and a portion existing as an aggregate as it is. On the other hand, since the acid-modified polyolefin resin used in the present invention has a certain molecular size, electrostatic aggregation does not easily occur and can be dispersed in a toner in a nearly uniform state. As a result, the variation in the content among the toner particles is reduced, and the chargeability of the toner becomes nearly uniform. For this reason, fluctuations in charging before and after durability can be suppressed.

  When Mpp is less than 10,000, the acid-modified polyolefin resin tends to aggregate and tends to be present in the toner particles in a biased manner. As a result, long-term concentration fluctuations tend to be large. On the other hand, when Mpp is larger than 100,000, the domain diameter becomes too large and the content of the acid-modified polyolefin resin in one toner particle tends to vary. As a result, the toner charge amount distribution varies. The Mpp of the acid-modified polyolefin resin is more preferably 12000 or more and 50000 or less.

  The reason why orthodichlorobenzene is used as the solvent in the measurement of Mpp is as follows. The acid-modified polyolefin resin used in the present invention has a high molecular weight and a partial crystal structure. Therefore, it is difficult to dissolve in a solvent such as THF, which is usually used in GPC measurement. On the other hand, orthodichlorobenzene has a high boiling point and can raise the temperature above the melting point of the acid-modified polyolefin resin, so that the acid-modified polyolefin resin can be dissolved. Therefore, in the present invention, orthodichlorobenzene is used as a solvent for determining the peak molecular weight of the acid-modified polyolefin resin.

  The acid-modified polyolefin resin used in the present invention has a maximum endothermic peak peak temperature (hereinafter also referred to as a melting point) at the time of temperature rise in a DSC curve measured by a differential scanning calorimeter of 60 ° C. or higher and 95 ° C. or lower. The peak temperature is more preferably 65 ° C. or higher and 85 ° C. or lower. When the peak temperature is within the above range, the acid-modified polyolefin resin does not inhibit the fixing of the toner, and the toner can have a good fixing property.

  When the peak temperature is lower than 60 ° C., when it is left in a harsh situation such as a high temperature and high humidity environment, the resin is partially compatible with the resin and the storage stability is deteriorated. On the other hand, when the peak temperature is higher than 95 ° C., toner fixability is lowered.

  In general, there is a correlation between the molecular weight and the melting point of polyolefin, and the higher the molecular weight, the higher the melting point. Since the acid-modified polyolefin used in the present invention has an Mpp within the above range, the peak molecular weight of a general olefin wax is several hundred to several thousand, so that it has a considerably large molecular weight. However, the acid-modified polyolefin resin of the present invention has a relatively low melting point as described above, regardless of the high molecular weight.

  A polyolefin resin having a large molecular weight and a low melting point has lower crystallinity than a normal one. The polyolefin resin having such properties is different in three-dimensional structure from a normal polyolefin resin used for wax or the like.

  A normal polyolefin resin used for wax or the like has a highly crystalline structure. For example, in polypropylene, ordinary polypropylene used for wax and the like is isotactic polypropylene having very good stereoregularity. Isotactic polypropylene has high crystallinity and excellent balance between rigidity and impact resistance, but tends to have a high melting point.

  On the other hand, polypropylene with low stereoregularity is called atactic polypropylene. Although atactic polypropylene has low heat resistance, it has excellent flexibility and tends to have a low melting point. Therefore, from the viewpoint of satisfying both the Mpp and the melting point range described above, the acid-modified polyolefin resin is preferably an acid-modified atactic polypropylene.

  As an index representing the stereoregularity of polypropylene, there is an isotactic Pendad fraction (AP fraction). It can be said that the smaller the AP fraction, the lower the stereoregularity. The acid-modified polyolefin resin used in the present invention preferably has an AP fraction of 35% to 60%. If the AP fraction is within the above range, the polyolefin portion of the acid-modified polyolefin resin is atactic polypropylene, so that it is easy to satisfy both the above-mentioned Mpp and melting point ranges.

  In addition, AP fraction is A. It means the isotactic fraction in the pentad unit in the polypropylene molecular chain measured by the signal of the methyl group of the 13C nuclear magnetic resonance spectrum proposed by Zambelli et al. In “Macromolecules, 6925 (1973)”.

  The AP fraction was measured by A. According to the assignment of the peak proposed by Zambelli et al. In “Macromolecules, 8687 (1975)”, the following apparatus and conditions are used.

Specifically, in the signal detected from the 13C nuclear magnetic resonance spectrum, the ratio of the 21.5 ppm peak to the total peak in the methyl carbon region (19 to 22 ppm) is calculated to determine the AP fraction.
Apparatus: JNM-EX400 type 13C-NMR apparatus manufactured by JEOL Ltd. Method: Proton complete decoupling method Concentration: 220 mg / ml Solvent: 90:10 (volume ratio) mixing of 1,2,4-trichlorobenzene and heavy benzene Solvent temperature: 130 ° C
Pulse width: 45 °
Pulse repetition time: 4 seconds Integration: 10,000 times

  In order to obtain atactic polypropylene, the stereoregularity of the polypropylene is lowered by adjusting the material constituting the resin, the catalyst used for the polymerization, and the like. Specifically, it is as follows.

  In order to obtain atactic polypropylene, it is preferable to polymerize in the presence of a metallocene compound (hereinafter also referred to as component [A]) and an aluminoxane compound (hereinafter also referred to as component [B]) as catalysts. Moreover, in that case, ethylene and / or a C4-C20 alpha olefin other than propylene can be used as a monomer. As a monomer used in addition to propylene, ethylene is preferable. It is preferable that 80% by mass or more of the propylene component is contained in the monomer. More preferably, it is 90 mass% or more.

  As the component [A], known metallocene compounds can be used without any limitation, but in order to control stereoregularity, a double-bridged biscyclopentadienyl derivative represented by the following general formula (A) is used. A transition metal compound as a ligand is preferred.

(In the above general formula (A), M represents a metal element of Groups 3 to 10 or a lanthanoid series of the periodic table, X ¹ represents a σ-bonded ligand, and Y ¹ represents a Lewis base. Q Is an integer of 1 to 5, and r is an integer of 0 to ^3. A ¹ and A ² are divalent bridging groups that bind two ligands, and are hydrocarbon groups having 1 to 20 carbon atoms. , A halogen-containing hydrocarbon group having 1 to 20 carbon atoms and a silicon-containing group, wherein R ^{3 to} R ⁸ are each a hydrogen atom, a halogen atom, a hydrocarbon group having 1 to 20 carbon atoms, or a halogen containing 1 to 20 carbon atoms. A hydrocarbon group, a silicon-containing group or a heteroatom-containing group, at least one of which is not a hydrogen atom, and R ^{3 to} R ⁸ may be the same or different from each other, and are adjacent groups; They may be bonded to each other to form a ring.)

  Specific examples of the transition metal compound represented by the general formula (A) include (1,2′-ethylene) (2,1′-ethylene) -bis (indenyl) zirconium dichloride, (1,2′-methylene). (2,1′-methylene) -bis (indenyl) zirconium dichloride, (1,2′-isopropylidene) (2,1′-isopropylidene) -bis (indenyl) zirconium dichloride, (1,2′-dimethylsilylene) ) (2,1′-dimethylsilylene) (3-methylcyclopentadienyl) (3′-methylcyclopentadienyl) zirconium dichloride.

  As the component [B], those shown below can be preferably used. As the aluminoxane compound, an aluminum compound represented by the general formula (B-1) or (B-2) is preferable.

  In General Formula (B-1) or (B-2), R is an alkyl group having 1 to 6, preferably 1 to 4 carbon atoms. Examples of R include a methyl group, an ethyl group, a propyl group, a butyl group, and an isobutyl group. Of these, a methyl group is particularly preferred. m is an integer of 4 to 100, preferably 6 to 80, particularly preferably 10 to 60.

  The manufacturing method of said aluminoxane compound should just employ | adopt well-known various methods. For example, water adsorbed in a hydrocarbon solvent using a method of directly reacting trialkylaluminum with water in a hydrocarbon solvent, copper sulfate hydrate having crystal water, aluminum sulfate hydrate, water-containing silica gel, etc. And a method in which trialkylaluminum is reacted.

  The ratio of component [A] to component [B] used is preferably 1: 1 to 1: 10000, more preferably 1: 5 to 1: 2000 in terms of molar ratio.

  When producing an acid-modified polyolefin resin, it is preferable to use an acid as a monomer and copolymerize with another monomer that forms a polyolefin moiety. The following are mentioned as an acid used for manufacture of acid-modified polyolefin resin. Unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, α-ethylacrylic acid and crotonic acid; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid, and monoester derivatives thereof; maleic anhydride. It is preferable to copolymerize the above monomers alone or in combination with other monomers.

  The addition amount of the acid-modified polyolefin resin is preferably 0.5 parts by mass or more and 5.0 parts by mass or less with respect to 100 parts by mass of the binder resin.

  Further, from the viewpoint of the total acid value of the acid-modified polyolefin resin present in the toner, Avp × (addition amount (part by mass) of the acid-modified polyolefin resin to 100 parts by mass of the binder resin) is 30 to 80. Is preferred.

  By designing the acid value in this way, the acid value derived from the charge control agent present in the toner can be appropriately controlled, and desired charging performance can be obtained.

  The acid-modified polyolefin resin used in the present invention preferably has a molecular weight distribution defined by a ratio (Mw / Mn) of the weight average molecular weight Mw to the number average molecular weight Mn of 3.0 or more and 10.0 or less. The conventional wax has (Mw / Mn) of around 1.0, whereas the acid-modified polyolefin resin used in the present invention has a broader molecular weight distribution. By controlling the molecular weight distribution in this way, the dispersibility of the acid-modified polyolefin resin is further improved, and a toner having a small charge distribution can be designed.

  The peak molecular weight (Mpr) of the binder resin is preferably smaller than the peak molecular weight (Mpp) of the acid-modified polyolefin resin. By making Mpr smaller than Mpp, the dispersibility of the acid-modified polyolefin resin in the binder resin is further improved, and the acid-modified polyolefin resin can easily maintain a desired domain diameter, leading to stable charging properties.

  Examples of the binder resin used in the toner of the present invention include the following. Vinyl resin, styrene resin, styrene copolymer resin, polyester resin, polyol resin, polyvinyl chloride resin, phenol resin, natural modified phenol resin, natural resin modified maleic acid resin, acrylic resin, methacrylic resin, polyvinyl acetate, Silicone resin, polyurethane resin, polyamide resin, furan resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone indene resin, petroleum resin. Among these, vinyl resins and polyester resins are preferably used.

  Among the components of the polyester resin, examples of the divalent acid component include the following dicarboxylic acids or derivatives thereof. Benzene dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride or their anhydrides or lower alkyl esters thereof; alkyl dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, azelaic acid or their anhydrides or lower thereof Alkyl esters; alkenyl succinic acids or alkyl succinic acids such as n-dodecenyl succinic acid, n-dodecyl succinic acid, or anhydrides thereof or lower alkyl esters thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid, citraconic acid, itaconic acid Or its anhydride or its lower alkyl ester.

  Among the components of the polyester resin, examples of the divalent alcohol component include the following. Ethylene glycol, polyethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, 1,5 -Pentanediol, 1,6-hexanediol, neopentyl glycol, 2-methyl-1,3-propanediol, 2-ethyl-1,3-hexanediol, 1,4-cyclohexanedimethanol (CHDM), hydrogenation Bisphenol A, bisphenol represented by formula (1) and derivatives thereof:

(In the formula, R is an ethylene or propylene group, x and y are each an integer of 0 or more, and the average value of x + y is 0 to 10.)
And diols represented by formula (2).

  The polyester resin is composed of a monovalent carboxylic acid compound, a monovalent alcohol compound, a trivalent or higher carboxylic acid compound, and a trivalent or higher alcohol compound in addition to the above divalent carboxylic acid compound and divalent alcohol compound. It may be contained as a component. Among them, in the present invention, it is preferable to use, as the binder resin, a polyester resin produced using a divalent or trivalent carboxylic acid compound as the acid component and using a divalent alcohol as the alcohol component.

  Examples of the monovalent carboxylic acid compound include aromatic carboxylic acids having 30 or less carbon atoms such as benzoic acid and p-methylbenzoic acid, and aliphatic carboxylic acids having 30 or less carbon atoms such as stearic acid and behenic acid. Examples of the monovalent alcohol compound include aromatic alcohols having 30 or less carbon atoms such as benzyl alcohol, and aliphatic alcohols having 30 or less carbon atoms such as lauryl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol. .

  Although it does not restrict | limit especially as a trivalent or more carboxylic acid compound, A trimellitic acid, trimellitic anhydride, pyromellitic acid, etc. are mentioned. Examples of the trivalent or higher alcohol compound include trimethylolpropane, pentaerythritol, and glycerin.

  A known method can be used for the production method of the polyester resin. For example, the aforementioned carboxylic acid compound and alcohol compound are charged together and polymerized through an esterification reaction or a transesterification reaction and a condensation reaction to produce a polyester resin. In the polymerization of the polyester resin, a polymerization catalyst such as titanium tetrabutoxide, dibutyltin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide, germanium dioxide or the like can be used. The polymerization temperature is preferably in the range of 180 ° C. or higher and 290 ° C. or lower.

  Examples of the monomer used for the vinyl resin include the following. Styrene; styrene derivatives such as o-methylstyrene, m-methylstyrene, p-methylstyrene, p-methoxystyrene, p-phenylstyrene; unsaturated monoolefins such as ethylene and propylene; methyl methacrylate, ethyl methacrylate Α-methylene aliphatic monocarboxylic acid esters such as; acrylic acid esters such as methyl acrylate, ethyl acrylate, and n-butyl acrylate. Furthermore, unsaturated dibasic acids such as maleic acid and fumaric acid; and unsaturated dibasic acid anhydrides such as maleic anhydride and alkenyl succinic anhydride.

  When using a vinyl resin as the binder resin, a monomer having an acid value such as the above acrylic esters or unsaturated dibasic acid is added, and the acid value is appropriately adjusted to 1 mgKOH / g or more and 40 mgKOH / g or less. There is a need.

  Examples of the polymerization initiator used for the polymerization of the vinyl polymer unit of the vinyl resin include 2,2′-azobisisobutyronitrile and 2,2′-azobis (4-methoxy-2,4-dimethylvalero). Nitrile), 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylbutyronitrile).

  The glass transition temperature (Tg) of the binder resin is preferably 45 ° C. or higher and 70 ° C. or lower. When the Tg of the binder resin is within the above range, the acid-modified polyolefin resin has a melting point near or slightly higher than the glass transition temperature of the binder resin. Therefore, when the toner is produced by the pulverization method, the acid-modified polyolefin resin can be mixed with the binder resin being semi-molten at the time of melt kneading. Accordingly, an appropriate share is applied to the melt-kneaded product, and the acid-modified polyolefin resin can be dispersed in a nearly uniform state.

  Furthermore, the glass transition temperature of the binder resin corresponds to the temperature at which the binder resin transitions from a glass state to a thermally deformable state, and at that temperature, the micro-Brownian motion of the molecular chains that make up the binder resin Has become active. For this reason, the acid-modified polyolefin resin undergoes a rapid viscosity change and is more easily dispersed in conjunction with the molecular motion of the binder resin.

  It is preferable that the binder resin has the following molecular weight distribution in the molecular weight distribution measured by gel permeation chromatography (GPC) soluble in tetrahydrofuran (THF). The peak molecular weight (Mp) of the binder resin is preferably 5,000 or more and 20,000 or less, and the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) is preferably 5 or more and 50 or less. .

  Further, from the viewpoint of imparting elasticity to the toner and further improving the material dispersibility, the binder resin preferably contains 3% by mass to 40% by mass of a THF-insoluble component, and more preferably 10% by mass to 30%. It is below mass%.

  In the present invention, a wax can be used as necessary to give the toner releasability.

  As the wax, hydrocarbon waxes such as low molecular weight polyethylene, low molecular weight polypropylene, microcrystalline wax, and paraffin wax are preferable because of easy dispersion in the toner and high releasability. If necessary, a small amount of one or two or more kinds of waxes may be used in combination.

  These waxes preferably have a peak molecular weight (Mpw) of an orthodichlorobenzene soluble component measured by gel permeation chromatography (GPC) method of 500 or more and 5000 or less.

Specific examples of the wax include the following. Biscol (registered trademark) 330-P, 550-P, 660-P, TS-200 (Sanyo Chemical Industries), High Wax 400P, 200P, 100P, 410P, 420P, 320P, 220P, 210P, 110P (Mitsui Chemicals) ), Sazole H1, H2, C80, C105, C77 (Schumann Sazol), HNP-1, HNP-3, HNP-9, HNP-10, HNP-11, HNP-12 (Nippon Seiki Co., Ltd.), Unilin (registered trademark) 350, 425, 550, 700, Unicid (registered trademark), Unicid (registered trademark) 350, 425, 550, 700 (Toyo Petrolite), wood wax, beeswax, rice wax, candelilla wax Carnauba wax (available from Celerica NODA).
The wax is preferably added in an amount of 1 to 20 parts by mass with respect to 100 parts by mass of the binder resin.

  The toner of the present invention may be a magnetic toner or a non-magnetic toner. When used as a magnetic toner, it is preferable to use magnetic iron oxide. As the magnetic iron oxide, iron oxides such as magnetite, maghemite, and ferrite are used.

  The amount of magnetic iron oxide contained in the toner is preferably 30% by mass or more and 120% by mass or less in the toner, and more preferably 45% by mass or more and 95% by mass.

These magnetic iron oxides have a magnetic property of 795.8 kA / m applied with a coercive force of 1.6 Am ² / kg or more and 12.0 kA / m or less, and a saturation magnetization of 50.0 Am ² / kg or more and 200.0 Am ² / kg or less. (Preferably 50.0 Am ² / kg or more and 100.0 Am ² / kg or less). Further, the residual magnetization is preferably 2.0 Am ² / kg or more and 20.0 Am ² / kg or less. The magnetic properties of magnetic iron oxide can be measured using a vibration type magnetometer, for example, VSM P-1-10 (manufactured by Toei Kogyo Co., Ltd.).

  When the toner of the present invention is used as a non-magnetic toner, carbon black or other conventionally known pigments or dyes or two or more of them can be used as a colorant. The addition amount of the colorant is preferably 0.1 parts by mass or more and 60.0 parts by mass or less, and more preferably 0.5 parts by mass or more and 50.0 parts by mass or less with respect to 100.0 parts by mass of the resin component.

  In the toner of the present invention, an inorganic fine powder is preferably used. Examples of the inorganic fine powder include the following. Fluorine-based resin powder such as vinylidene fluoride fine powder and polytetrafluoroethylene fine powder; fine powder silica such as wet process silica and dry process silica. Among these, dry-process silica produced by vapor phase oxidation of a silicon halogen compound is preferable.

The average primary particle size of the inorganic fine powder is preferably in the range of 0.001 μm to 2 μm, particularly preferably 0.002 μm to 0.2 μm. From the viewpoint of fluidity imparting ability, the inorganic fine powder preferably has a BET specific surface area of 50 m ² / g or more and 300 m ² / g or less.

  The inorganic fine powder is preferably subjected to a hydrophobic treatment with an organosilicon compound. Examples of organosilicon compounds include the following. Hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α- Chlorethyltrichlorosilane, β-chloroethyltrichlorosilane, chloromethyldimethylchlorosilane, triorganosilyl mercaptan, trimethylsilyl mercaptan, triorganosilyl acrylate, vinyldimethylacetoxysilane, dimethylethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, 1 -Hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyl Ludisiloxane and dimethylpolysiloxane containing 2 to 12 siloxane units per molecule and containing hydroxyl groups bonded to one Si at each terminal unit. These are used alone or in a mixture of two or more.

The inorganic fine powder may be treated with silicone oil, or may be treated in combination with the hydrophobic treatment. As the silicone oil, it is preferable to use one having a viscosity at 25 ° C. of 30 mm ² / s or more and 1000 mm ² / s or less. Examples of the silicone oil include dimethyl silicone oil, methylphenyl silicone oil, α-methylstyrene modified silicone oil, chlorophenyl silicone oil, and fluorine modified silicone oil.

  The inorganic fine powder is used in an amount of 0.01 to 8.0 parts by weight, preferably 0.1 to 4.0 parts by weight, based on 100.0 parts by weight of the toner particles.

  Other external additives may be added to the toner of the present invention as necessary. For example, there are resin fine particles and inorganic fine particles that function as a charge auxiliary agent, conductivity imparting agent, fluidity imparting agent, anti-caking agent, release agent at the time of fixing with a heat roller, lubricant, and abrasive.

  Examples of the lubricant include polyethylene fluoride powder, zinc stearate powder, and polyvinylidene fluoride powder. Of these, polyvinylidene fluoride powder is preferred. Examples of the abrasive include cerium oxide powder, silicon carbide powder, and strontium titanate powder.

  As a method for producing the toner particles used in the present invention, known methods such as a pulverization method, a suspension polymerization method, a dissolution suspension method, and an emulsion aggregation method can be used. Among them, the toner particles used in the present invention are preferably produced by a pulverization method. By producing toner particles by a pulverization method, the dispersion of the acid-modified polyolefin resin becomes better, and the acid-modified polyolefin resin can be easily present in the toner particles with an appropriate domain size. A specific manufacturing method is as follows. A binder resin, a colorant, an acid-modified polyolefin resin, and the like are sufficiently mixed by a mixer such as a Henschel mixer or a ball mill, and then melt-kneaded using a heat kneader such as a heating roll, a kneader, or an extruder. Thereafter, after cooling and solidification, the melt-kneaded product is pulverized, and the pulverized product is classified. Further, if necessary, desired additives are sufficiently mixed by a mixer such as a Henschel mixer to obtain a toner.

  A method for measuring physical properties of the toner of the present invention is as follows. In addition, the physical-property value in an Example is also measured by the following method.

<Measurement of acid value>
The acid value is expressed in mg of potassium hydroxide necessary to neutralize the acid contained in 1 g of the sample. The acid value of the binder resin and the acid-modified polyolefin resin is measured according to JIS K 0070-1992. Specifically, it is measured according to the following procedure.

(1) Preparation of Reagent 1.0 g of phenolphthalein is dissolved in 90 ml of ethyl alcohol (95 vol%), and ion exchanged water is added to make 100 ml to obtain a phenolphthalein solution.

  7 g of special grade potassium hydroxide is dissolved in 5 ml of water, and ethyl alcohol (95 vol%) is added to make 1 L. In order not to touch carbon dioxide, etc., put in an alkali-resistant container and let stand for 3 days, then filter to obtain a potassium hydroxide solution. The obtained potassium hydroxide solution is stored in an alkali-resistant container. Factor of the potassium hydroxide solution is 25 ml of 0.1 mol / L hydrochloric acid in an Erlenmeyer flask, added several drops of the phenolphthalein solution, titrated with the potassium hydroxide solution, and required for neutralization. Determine from the amount of solution. As the 0.1 mol / L hydrochloric acid, one prepared according to JIS K 8001-1998 is used.

(2) Operation (A) Main test 2.0 g of the pulverized binder resin or acid-modified polyolefin resin was precisely weighed into a 200 ml Erlenmeyer flask, and 100 ml of a mixed solution of toluene / ethanol (2: 1) was added. Dissolves over time. Subsequently, several drops of the phenolphthalein solution is added as an indicator, and titration is performed using the potassium hydroxide solution. The end point of titration is when the light red color of the indicator lasts for about 30 seconds.

(B) Blank test Titration is performed in the same manner as above except that no sample is used (that is, only a mixed solution of toluene / ethanol (2: 1) is used).

  (3) The acid value is calculated by substituting the obtained result into the following formula.

A = [(C−B) × f × 5.61] / S
Here, A: acid value (mgKOH / g), B: addition amount (ml) of a potassium hydroxide solution in a blank test, C: addition amount (ml) of a potassium hydroxide solution in this test, f: potassium hydroxide Solution factor, S: sample (g).

<Peak temperature of maximum endothermic peak during temperature rise>
The peak temperature of the maximum endothermic peak of the acid-modified polyolefin resin and wax is measured according to ASTM D3418-82 using a differential scanning calorimeter “Q1000” (manufactured by TA Instruments).

  The temperature correction of the device detection unit uses the melting points of indium and zinc, and the correction of heat uses the heat of fusion of indium.

  Specifically, about 2 mg of acid-modified polyolefin resin (or wax) is precisely weighed, placed in an aluminum pan, and an empty aluminum pan is used as a reference, with a measurement temperature range of 30 to 200 ° C. The measurement is performed at a heating rate of 10 ° C./min. In the measurement, the temperature is once raised to 200 ° C., subsequently lowered to 30 ° C., and then the temperature is raised again. The maximum endothermic peak of the DSC curve in the temperature range of 30 to 200 ° C. in the second temperature raising process is defined as the peak temperature of the maximum endothermic peak of the endothermic curve in the DSC measurement of the acid-modified polyolefin resin (or wax).

<Molecular weight measurement of acid-modified polyolefin resin and wax>
The molecular weight distribution of the acid-modified polyolefin resin and wax is measured by gel permeation chromatography (GPC) as follows.

To o-dichlorobenzene for gel chromatography, special grade 2,6-di-t-butyl-4-methylphenol (BHT) is added so that the concentration becomes 0.10 wt / vol%, and dissolved at room temperature. The sample and the above-mentioned BHT-added o-dichlorobenzene are put into a sample bottle and heated on a hot plate set at 150 ° C. to dissolve the sample. Once the sample has melted, place it in a preheated filter unit and place it on the body. The sample that has passed through the filter unit is used as a GPC sample. The sample solution is adjusted so that the concentration is about 0.15% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC-8121GPC / HT (manufactured by Tosoh Corporation)
Detector: RI for high temperature
Column: TSKgel GMHHR-H HT 2 series (manufactured by Tosoh Corporation)
Temperature: 135 ° C
Solvent: o-dichlorobenzene for gel chromatography (BHT added at 0.10 wt / vol%)
Flow rate: 1.0 ml / min
Injection volume: 0.4ml

  In calculating the molecular weight of the sample, standard polystyrene resin (for example, trade name “TSK Standard Polystyrene F-850, F-450, F-288, F-128, F-80, F-40, F-20, F— 10, F-4, F-2, F-1, A-5000, A-2500, A-1000, A-500 ", manufactured by Tosoh Corporation) are used.

<Measurement of insoluble THF in binder resin>
About 1.0 g of resin is weighed, and its weight is defined as W1 (g). The weighed resin is placed in a cylindrical filter paper (for example, No. 86R size 28 × 100 mm, manufactured by Advantech Toyo Co., Ltd.), placed in a Soxhlet extractor, and extracted for 16 hours using 200 ml of THF as a solvent. At this time, extraction is performed at a reflux rate such that the solvent extraction cycle is about once every 4 minutes.

  After the extraction is completed, the cylindrical filter paper is taken out and vacuum-dried at 40 ° C. for 8 hours, and the extraction residue is weighed. The weight of this extraction residue is assumed to be W2 (g). The measurement of the THF-insoluble content of the binder resin is obtained from the following formula.

THF insoluble matter = (W2 / W1) × 100 (%)
<Molecular weight measurement of binder resin>
The column is stabilized in a heat chamber at 40 ° C., THF is flowed through the column at this temperature as a solvent at a flow rate of 1 ml / min, and about 100 μl of the THF sample solution is injected and measured. In measuring the molecular weight of a sample, the molecular weight distribution of the sample is calculated from the relationship between the logarithmic value of a calibration curve prepared from several types of monodisperse polystyrene standard samples and the count value. As a standard polystyrene sample for preparing a calibration curve, for example, one having a molecular weight of about 10 ² to 10 ⁷ manufactured by Tosoh Corporation or Showa Denko KK is suitably used, and at least about 10 standard polystyrene samples are used. The detector uses an RI (refractive index) detector. In addition, it is preferable to combine a plurality of commercially available polystyrene gel columns as the column. of _{TSKgel G1000H (H XL), G2000H} (H XL), G3000H (H XL), G4000H (H XL), G5000H (H XL), G6000H (H XL), G7000H (H XL), include a combination of TSKguard column be able to.

Moreover, a sample is produced as follows.
Place the sample in THF and leave it at 25 ° C. for several hours, then shake it well, mix well with THF (until the sample is no longer integrated), and let stand for more than 12 hours. At that time, the standing time in THF is set to 24 hours. Then, a sample processing filter (pore size of 0.2 μm or more and 0.5 μm or less, for example, Myssho Disc H-25-2 (manufactured by Tosoh Corporation)) can be used as a GPC sample. The sample concentration is adjusted so that the resin component is 0.5 mg / ml or more and 5.0 mg / ml or less.

<Measurement method of weight average particle diameter (D4)>
The weight average particle diameter (D4) of the toner is determined based on the precise particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) having a 100 μm aperture tube. Using the attached dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for setting and analyzing the measurement data, the measurement data is measured with 25,000 effective channels. Analyze and calculate.

  As the electrolytic aqueous solution used for the measurement, special grade sodium chloride is dissolved in ion-exchanged water so as to have a concentration of about 1% by mass, for example, “ISOTON II” (manufactured by Beckman Coulter, Inc.) can be used.

Prior to measurement and analysis, the dedicated software is set as follows.
In the “Standard Measurement Method (SOM) Change Screen” of the dedicated software, set the total count in the control mode to 50000 particles, set the number of measurements once, and set the Kd value to “standard particles 10.0 μm” (Beckman Coulter, Inc.) Set the value obtained using The threshold and noise level are automatically set by pressing the threshold / noise level measurement button. Also, the current is set to 1600 μA, the gain is set to 2, the electrolyte is set to ISOTON II, and the aperture tube flash after measurement is checked.

  In the “pulse to particle size conversion setting screen” of the dedicated software, the bin interval is set to logarithmic particle size, the particle size bin is set to 256 particle size bin, and the particle size range is set to 2 μm to 60 μm.

The specific measurement method is as follows.
[1] About 200 ml of the electrolytic aqueous solution is placed in a glass 250 ml round bottom beaker exclusively for Multisizer 3, set on a sample stand, and the stirrer rod is stirred counterclockwise at 24 rpm. Then, dirt and bubbles in the aperture tube are removed by the “aperture flush” function of the analysis software.

  [2] About 30 ml of the electrolytic aqueous solution is put in a glass 100 ml flat bottom beaker, and “Contaminone N” (nonionic surfactant, anionic surfactant, organic builder consisting of organic builder) is used as a dispersant. About 0.3 ml of a diluted solution obtained by diluting a 10% by weight aqueous solution of a neutral detergent for washing a vessel (made by Wako Pure Chemical Industries, Ltd.) 3 times with ion exchange water is added.

  [3] Two oscillators with an oscillation frequency of 50 kHz are incorporated in a state where the phase is shifted by 180 degrees, and placed in a water tank of an ultrasonic disperser “Ultrasonic Dispersion System Tetora150” (manufactured by Nikki Bios) with an electrical output of 120 W A fixed amount of ion-exchanged water is added, and about 2 ml of the above-mentioned Contaminone N is added to this water tank.

  [4] The beaker of [2] is set in the beaker fixing hole of the ultrasonic disperser, and the ultrasonic disperser is operated. And the height position of a beaker is adjusted so that the resonance state of the liquid level of the electrolyte solution in a beaker may become the maximum.

  [5] In a state where the electrolytic aqueous solution in the beaker of [4] is irradiated with ultrasonic waves, about 10 mg of toner is added to the electrolytic aqueous solution little by little and dispersed. Then, the ultrasonic dispersion process is continued for another 60 seconds. In the ultrasonic dispersion, the temperature of the water tank is appropriately adjusted so as to be 10 ° C. or higher and 40 ° C. or lower.

  [6] The [5] aqueous electrolyte solution in which the toner is dispersed is dropped using a pipette into the [1] round bottom beaker installed in the sample stand, and the measured concentration is adjusted to about 5%. Measurement is performed until the number of measured particles reaches 50,000.

  [7] The fixed data is analyzed with the dedicated software attached to the apparatus, and the weight average particle diameter (D4) is calculated. The “average diameter” on the analysis / volume statistics (arithmetic average) screen when the graph / volume% is set with the dedicated software is the weight average particle diameter (D4).

<Measurement of magnetic properties of magnetic iron oxide particles>
Using a vibrating sample magnetometer VSM-P7 manufactured by Toei Industry Co., Ltd., measurement is performed at a sample temperature of 25 ° C. and an external magnetic field of 795.8 kA / m.

<Measurement of average primary particle diameter of magnetic iron oxide particles>
The average primary particle diameter is obtained by observing magnetic iron oxide particles with a scanning electron microscope (magnification 40000 times), measuring the ferret diameter of 200 particles, and determining the number average particle diameter. In this example, S-4700 (manufactured by Hitachi, Ltd.) was used as the scanning electron microscope.

  Hereinafter, the present invention will be specifically described based on examples. The number of parts in this example is based on mass.

<Manufacture of charge control resin 1>
In a polymerization vessel having an internal capacity of 2000 L subjected to nitrogen substitution, 500 kg of a mixture of propylene and ethylene with a mixing ratio of 98: 2 (propylene 98 parts by mass, ethylene 2 parts by mass) and maleic acid 15 kg (3.0 parts by mass) Was loaded. As a catalyst, methylaluminoxane was charged with 10 mmol in terms of aluminum, (1,2′-dimethylsilylene) (2,1′-dimethylsilylene) -bis (indenyl) zirconium dichloride, 10 μmol, and further hydrogen 90 NL, The internal temperature was raised to 50 ° C. and copolymerization was carried out for 2.0 hours.

  After completion of the polymerization, the obtained polymer was dried under reduced pressure to obtain a charge control resin 1 which is an acid-modified polyolefin resin.

<Production example of charge control resins 2 to 17>
As shown in Table 1, the charge of the acid-modified polyolefin resin is the same as that of the charge control resin 1 except that the mixing ratio of propylene and ethylene, the amount of maleic acid added, the polymerization temperature and time, and the hydrogen flow rate are changed. Control resins 2 to 17 were obtained.

<Production Example of Charge Control Resin 18>
In 1500 parts of xylene, 985 parts by weight of low molecular weight polypropylene (weight average molecular weight 9500, number average molecular weight 3300, melt viscosity of 0.7 poise at 160 ° C.) and 15 parts by weight of maleic anhydride were dispersed by heating. Thereafter, 10 parts by mass of dicumyl peroxide was added and reacted at 100 ° C. for 4 hours, and then xylene was distilled off to obtain a charge control resin 18.

<Production Example of Charge Control Resin 19>
1,4-butanediol 800 parts by mass, 1,6-hexanediol 130 parts by mass, fumaric acid 980 parts by mass, adipic acid 396 parts by mass, hydroquinone 2 parts by mass and dibutyltin oxide 4 parts by mass in a nitrogen atmosphere at 160 ° C. For 5 hours, and then heated to 200 ° C. for 1 hour. Furthermore, it was made to react until the resin of a desired molecular weight was obtained at 8.3 kPa, and the crystalline resin 1 was obtained. This crystalline resin 1 was used as a charge control resin 19.

<Production Example of Charge Control Resin 20>
Polyaryl stearate (DSC endothermic peak temperature: 58 ° C., Mpp: 110000, acid value 42 mg KOH / g, melt viscosity (140 ° C.) 4800 cP) was used as the charge control resin 20.

<Production example of charge control resin 21>
Maleic acid-modified polypropylene wax (DSC endothermic peak temperature: 98 ° C., Mpp: 9800, acid value 8 mgKOH / g) was used as the charge control resin 21.

<Production Example of Charge Control Resin 22>
In a nitrogen atmosphere, 911 parts by mass of 1,4-butanediol, 130 parts by mass of 1,6-hexanediol, 638 parts by mass of fumaric acid, 792 parts by mass of adipic acid, 2 parts by mass of hydroquinone, and 4 parts by mass of dibutyltin oxide were added at 160 ° C. For 5 hours, and then heated to 200 ° C. for 1 hour. Furthermore, it was made to react until a resin with a desired molecular weight was obtained at 8.3 kPa, thereby obtaining a crystalline resin 2. This crystalline resin 2 was used as a charge control resin 22.
Table 2 shows various physical properties of the charge control resins 1 to 22.

<Example of production of binder resin 1>
・ Terephthalic acid 26.0 mol%
Adipic acid 15.0 mol%
・ Trimellitic acid 5.0mol%
-33.0 mol% of bisphenol derivatives represented by the formula (1)
(Propylene oxide 2.5 mol adduct)
-Bisphenol derivative represented by the formula (1) 21.0 mol%
(Ethylene oxide 2.5 mol adduct)

  A 4-necked flask is charged with 0.02 parts by mass of tin 2-ethylhexanoate as an esterification catalyst and an acid component and an alcohol component as shown above, and a pressure reducing device, a water separator, a nitrogen gas introducing device, a temperature measuring device, and a stirring device. The reaction was carried out by raising the temperature to 230 ° C. in a nitrogen atmosphere. After completion of the reaction, the product was taken out from the container, cooled and pulverized to obtain a binder resin 1.

<Production example of binder resins 2 to 7, 9>
Binder resins 2 to 7 and 9 were produced in the same manner as in the production example of the binder resin 1 except that the monomer composition ratio and the reaction temperature were changed as shown in Table 3.

<Example of production of binder resin 8>
・ Styrene 71 parts by mass ・ Acrylic acid-n-butyl 24 parts by mass ・ Monobutyl maleate 5 parts by mass ・ Divinylbenzene 0.005 parts by mass ・ 2,2-bis (4,4-di-tert-butylperoxycyclohexyl) Propane (half-life 10 hours, temperature: 92 ° C.) 0.1 parts by mass

  Into a four-necked flask, 300 parts by mass of xylene is added, and the inside of the container is sufficiently replaced with nitrogen while stirring, and then heated to 160 ° C. and refluxed. Under this reflux, the above mixed solution was added dropwise over 4 hours and then held for 2 hours to complete the polymerization, whereby a binder resin 8 was obtained.

<Example of production of binder resin 10>
-Styrene 76 parts by mass-Acrylic acid-n-butyl 24 parts by mass-Divinylbenzene 0.1 part by mass-2,2-bis (4,4-di-tert-butylperoxycyclohexyl) propane (half-life 10 hours, (Temperature: 92 ° C.) 0.01 parts by mass

Into a four-necked flask, 300 parts by mass of xylene is added, and the inside of the container is sufficiently replaced with nitrogen while stirring, and then heated to 160 ° C. and refluxed. Under this reflux, the above mixed solution was dropped over 4 hours, and then kept for 4 hours to complete the polymerization, and a binder resin 10 was obtained.
Table 3 shows various physical properties of the binder resins 1 to 10.

<Example 1>
Binder resin 1 100.0 parts by mass Magnetic iron oxide particles 90.0 parts by mass (average particle size: 0.14 μm, Hc (coercive force) = 11.5 kA / m, σs (saturation magnetization) = 84.0 Am ² / kg, σr (residual magnetization) = 16.0 Am ² / kg)
Fischer-Tropsch wax 2.0 parts by mass (peak temperature of DSC endothermic peak: 105 ° C.)
-Charge control resin 1 2.0 parts by mass

  After the above materials were premixed with a Henschel mixer, they were melt-kneaded with a twin-screw kneading extruder at 150 ° C. and a paddle rotation speed of 200 rpm. The obtained kneaded product was cooled, coarsely pulverized with a hammer mill, and then pulverized with a fine pulverizer using a jet stream. The finely pulverized powder thus obtained was classified using a multi-division classifier utilizing the Coanda effect to obtain negative triboelectrically chargeable toner particles having a weight average particle diameter of 6.8 μm.

To 100 parts by mass of toner particles, 1.0 part by mass of hydrophobic silica fine powder (BET 180 m ² / g, silane coupling treatment and silicone oil treatment, hydrophobization degree 90%) is externally added and mixed, and the mesh has a mesh size of 150 μm. And a negative triboelectric charge toner 1 was obtained. Various physical properties of the toner are as shown in Table 4.

  A commercially available digital copying machine image Press 1135 (manufactured by Canon Inc.) was used as an evaluation machine in this example. In this evaluation machine, the following evaluation was performed using the toner 1. In addition, regarding the evaluation using the toner 1, good results were obtained in all items.

<Short-term concentration fluctuation>
Using the above evaluation machine, in a normal temperature and humidity environment (23 ° C., 60% RH), using A4 plain paper (64 g / m ² paper), the left half is solid black and the right half is white. 10000 images of% were output. The image densities of 9100th, 9500th, 9700th, and 10000th sheets were measured. In the measurement of the image density, an SPI filter was used with a Macbeth reflection densitometer (manufactured by Macbeth Co., Ltd.), and the upper end, the center, and the lower end of each solid black portion of each image were measured, and the average value was used as the image density. Of the four image densities, the difference (Dmax−Dmin) between the maximum image density value (Dmax) and the minimum image density value (Dmin) was used as an indicator of short-term density fluctuation. The evaluation results are shown in Table 5.
A: Dmax−Dmin is 0.
B: Dmax−Dmin is 0.01 or more and 0.02 or less.
C: Dmax−Dmin is 0.03 or more and 0.04 or less.
D: Dmax−Dmin is 0.05 or more.

<Long-term concentration fluctuation>
Using the above evaluation machine, 100,000 sheets of horizontal line images with a printing ratio of 5% were output using A4 plain paper (64 g / m ² paper) in a normal temperature and humidity environment (23 ° C., 60% RH). At that time, black images were output on the 10th, 10,000th, 50,000th, 70th, 100,000th images. The reflection density at the four corners and the central five points of the solid black image was measured with a Macbeth reflection densitometer (manufactured by Macbeth) using an SPI filter, and the average value was taken as the image density. Of the five solid black images, the difference (Dmax−Dmin) between the maximum value (Dmax) of the image density and the minimum value (Dmin) of the image density was used as an index of long-term density fluctuation. The evaluation results are shown in Table 5.
A: Dmax−Dmin is 0.
B: Dmax−Dmin is 0.01 or more and 0.02 or less.
C: Dmax−Dmin is 0.03 or more and 0.04 or less.
D: Dmax−Dmin is 0.05 or more.

<1 job concentration fluctuation>
Using the above evaluation machine, 4999 horizontal line images with a printing ratio of 5% were output using A4 plain paper (64 g / m ² paper) in a normal temperature and low humidity environment (23 ° C., 5% RH). A solid black image was output. Thereafter, the evaluation machine was stopped for 30 minutes, and one black image was output again after 30 minutes. The transmission density at the four corners and the central five points of the solid black image was measured using a Macbeth transmission densitometer RD914 model, and the average value was used as the image density. The difference in image density before and after leaving (5001st sheet average density−5000th sheet average density) was evaluated as the 1 job density fluctuation evaluation. Note that the transmission density is measured because it is possible to evaluate a minute density change that does not show a significant difference in the reflection density. The evaluation results are shown in Table 5.
A: The difference in image density before and after being left is zero.
B: The difference in image density before and after being left is 0.01 to 0.02.
C: The difference in image density before and after being left is 0.03 or more and 0.04 or less.
D: The difference in image density before and after being left is 0.05 or more.

<Rising concentration in the morning>
Using the above-mentioned evaluation machine, 4999 horizontal line images with a printing ratio of 5% were output using A4 plain paper (64 g / m ² paper) in a high temperature and high humidity environment (32 ° C., 80% RH) and 5000 sheets. A stunning black image was output. Thereafter, the evaluation machine was stopped for 3 days, and a solid black image was output again after 3 days. The reflection density at the four corners and the central five points of the solid black image was measured with a Macbeth reflection densitometer (manufactured by Macbeth) using an SPI filter, and the average value was taken as the image density. The difference in image density before and after being left (average density on the 5000th sheet−average density on the 5001st sheet) was used as an evaluation of the rising density in the morning. The evaluation results are shown in Table 5.
A: The difference in image density before and after being left is zero.
B: The difference in image density before and after being left is 0.01 to 0.03.
C: The difference in image density before and after being left is 0.04 or more and 0.06 or less.
D: The difference in image density before and after being left is 0.07 or more.

<Initial concentration>
One solid black image was output using A4 plain paper (64 g / m ² paper) in a normal temperature and humidity environment (23 ° C., 60% RH) using the above evaluation machine. The reflection density at the four corners and the central five points of this solid black image was measured with a Macbeth reflection densitometer (manufactured by Macbeth) using an SPI filter, and the average value was taken as the image density.
The absolute value of this image density was used as an index for initial density evaluation. The evaluation results are shown in Table 5.
A: The initial reflection density is 1.45 or more.
B: The initial reflection density is 1.42 or more and 1.44 or less.
C: The initial reflection density is 1.38 or more and 1.41 or less.
D: The initial reflection density is 1.37 or less.

<Cover evaluation>
Using the above evaluation machine, 4999 horizontal line images with a printing ratio of 5% were output using A4 plain paper (64 g / m ² paper) in a normal temperature and low humidity environment (23 ° C., 5% RH). A solid white image was output. The solid white image was measured using a REFECTMETER MODEL TC-6DS manufactured by Tokyo Denshoku. The filter was a green filter, and the fog was calculated from the following formula.
Fog (%) = reflectance of plain paper before passing (%)-reflectance on solid white paper (%)
The evaluation criteria for fogging are as follows. The evaluation results are shown in Table 5.
A: The fog is less than 0.5%.
B: Fog is 0.5% or more and less than 1.0%.
C: The fog is 1.0% or more and less than 1.5%.
D: Fog is 1.5% or more.

<Preservation evaluation>
About 10 g of toner is put in a 100 cc plastic cup, left in an environment of 40 ° C. and 95% for 7 days, and left in an environment of 23 ° C. and 60% for 1 day. Was used as an evaluation index.

As a measuring apparatus, a powder tester (manufactured by Hosokawa Micron Co., Ltd.) having a digital vibrometer (manufactured by DEGIBILATION METER MODEL 1332, manufactured by SHOWA SOKKI CORP.) Was used. The sieves were stacked in the order of 60 mesh, 100 mesh, and 200 mesh so that the 60 mesh sieve was on the top of the shaking table. Then, 5 g of the toner was placed on a 60-mesh sieve, the displacement value of the digital vibrometer was adjusted to 0.60 mm (peak-to-peak), and vibration was applied for 15 seconds. Thereafter, the mass of the sample remaining on each sieve was measured, and the degree of aggregation was calculated based on the following formula.
Aggregation degree (%) = (residual sample mass on a 60 mesh sieve (g) / 5 g) × 100 + (residual sample mass on a 100 mesh sieve (g) / 5 g) × 60 + (residual sample mass on a 200 mesh sieve ( g) / 5g) × 20
A: The degree of aggregation is less than 15%.
B: The degree of aggregation is 15% or more and less than 20%.
C: Aggregate is 20% or more and less than 25%.
D: The aggregate is 25% or more.

<Examples 2 to 17>
Toners 2 to 17 were obtained in the same manner as in Example 1 except that the binder resin and charge control resin used were changed as shown in Table 4. Table 4 shows properties of the toners 2 to 17. In addition, toners 2 to 17 were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 5.
Examples 7, 9, 11, 13, 14, 16, and 17 are described as reference examples.

<Comparative Examples 1 to 9>
Toners 18 to 26 were obtained in the same manner as in Example 1 except that the materials used were changed as shown in Table 4. Table 4 shows various physical properties of Toners 18 to 26. Further, the toners 18 to 26 were evaluated in the same manner as in Example 1. The evaluation results are shown in Table 5.

Claims (4)

A toner having toner particles containing a binder resin and a colorant,
The binder resin has an acid value (Avr) of 1 mgKOH / g or more and 40 mgKOH / g or less,
The toner particles contain an acid-modified polyolefin resin,
The acid-modified polyolefin resin is
(1) The acid value (Avp) is 21 mgKOH / g or more and 40 mgKOH / g or less,
(2) The peak temperature of the maximum endothermic peak at the time of temperature rise in the DSC curve measured by a differential scanning calorimeter is 60 ° C. or higher and 95 ° C. or lower,
(3) The peak molecular weight (Mpp) of the ortho-dichlorobenzene-soluble component of the acid-modified polyolefin resin as measured by gel permeation chromatography is 10,000 or more and 100,000 or less.
Toner characterized by the above.   2. The ratio (Mw / Mn) of the weight average molecular weight Mw and the number average molecular weight of the orthodichlorobenzene-soluble component of the acid-modified polyolefin resin is 3.0 or more and 10.0 or less. toner.   The toner according to claim 1, wherein a peak molecular weight (Mpr) of the orthodichlorobenzene-soluble component of the binder resin is smaller than a peak molecular weight (Mpp) of the acid-modified polyolefin resin. 4. The toner according to claim 1, wherein the acid-modified polyolefin resin is an acid-modified atactic polypropylene and has an AP fraction of 35% to 60%.