JP2015121576A - Toner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toner that is provided with hot offset resistance remarkably superior to the prior art in addition to low-temperature fixability.SOLUTION: There is provided a toner that contains an amorphous polyester resin and crystalline polyester, where in an endothermic curve at the temperature rise of the toner measured by a differential scanning calorimetry device (DSC), the endothermic amount ΔH derived from the crystalline polyester is 1.0 J/g or more and 5.0 J/g or less; on the cross section of the toner observed by transmission electron microscope (TEM), crystals of the crystalline polyester observed in a needle-like shape are dispersed; in a number distribution of the length of the major axis of the crystals, there are 30 number% or more of the cross sections of the crystal having a length of the major axis of 100 nm or more and 250 nm or less.

Description

  The present invention relates to a toner used in an electrophotographic system, an electrostatic recording system, an electrostatic printing system, and a toner jet system.

  In recent years, with the widespread use of electrophotographic full-color copiers, demands for high-speed printing and energy saving are increasing. In order to cope with high-speed printing, a technique for melting the toner more quickly in the fixing process has been studied. Further, as an energy saving measure, in order to reduce power consumption in the fixing process, a technique for fixing toner at a lower fixing temperature has been studied.

  In order to cope with high-speed printing and improve the low-temperature fixability of the toner, there are methods such as lowering the glass transition point and softening point of the toner binder resin and using a binder resin having sharp melt properties. In recent years, in order to further improve the sharp melt property, toners in which a crystalline polyester resin is contained in a binder resin have been developed. By containing crystalline polyester in the toner, it is possible to improve the storage stability and durability since the hardness can be maintained up to the fixing temperature while rapidly melting at the fixing temperature.

  For toners containing crystalline polyester, various technical proposals have been made regarding the presence of crystalline polyester in the toner.

  Japanese Patent Application Laid-Open No. 2005-228867 proposes a method for improving the fixing separation property by defining the relationship between the crystal domain cross-sectional area of the crystalline polyester in the toner and the release agent domain cross-sectional area. According to this, the balance between the speed at which the wax exudes to the toner surface and the melting speed of the toner binder resin is optimized, and in addition to the low-temperature fixability, the fixing separation property is improved.

  In Patent Document 2, in addition to the main binder resin and the crystalline polyester, a crystalline polyester dispersant is used to define each solubility parameter. This prevents the crystalline polyester from being exposed to the toner surface layer, and finely disperses the crystalline polyester inside the toner particles, thereby suppressing toner filming to other members and improving hot offset resistance. I am trying.

  Patent Document 3 proposes a toner in which a toner particle surface layer is covered with an amorphous resin in a toner in which crystalline polyester is finely dispersed. As a result, a toner containing crystalline polyester and excellent in low-temperature fixability satisfies heat storage stability and durability stability.

  In Patent Document 4, the hot offset resistance is improved by setting the long axis diameter of the crystalline polyester crystal in the toner to 0.5 μm or more and 1/2 or less of the toner diameter.

  On the other hand, in the recent market, there is an increasing demand for a medium to be fixed and a higher image output speed, and the toner adheres to the fixing member even if the fixing portion becomes hot while satisfying the low temperature fixing property. There is a need for toners that are more resistant to hot offset and have a higher level of hot offset resistance. In particular, in markets around the world, stable image output is required under various conditions such as continuous output under a high room temperature environment and heavy use of thin paper, and it is necessary to prevent hot offset even under more severe conditions.

  However, in all of the technologies so far, with toners with improved low-temperature fixability, the hot offset resistance remains at a level that satisfies the same performance as the conventional technology. The offset property has not been improved so much, and there is room for further performance improvement.

Japanese Unexamined Patent Publication No. 2011-145587 JP 2012-63559 A JP 2012-182391 A JP 2004-279476 A

  An object of the present invention is to provide a toner that solves the above problems. Specifically, an object of the present invention is to provide a toner that can exhibit sufficient hot offset resistance even under severe hot offset conditions while satisfying low-temperature fixability.

The present invention is a toner containing an amorphous polyester resin and a crystalline polyester,
In the endothermic curve at the time of temperature rise measured by the differential scanning calorimeter (DSC) of the toner, the endothermic amount ΔH derived from the crystalline polyester is 1.0 J / g or more and 5.0 J / g or less,
In the cross section of the toner observed by a transmission electron microscope (TEM), crystals of the crystalline polyester observed in a needle shape are dispersed, and in the number distribution of the major axis length of the crystals, the major axis length Is a toner characterized in that there are 30% by number or more of the crystal cross section of 100 nm to 250 nm.

  According to the present invention, low temperature fixability can suppress power consumption in the fixing device, achieve energy saving, and exhibit excellent hot offset resistance, thereby making various conditions that make hot offset severe. In this case, it is possible to provide a toner capable of obtaining a high-quality fixed image product.

FIG. 3 is a cross-sectional view of the toner of the present invention using an electron beam transmission microscope. FIG. 3 is a diagram showing a major axis length and a minor axis length of a crystalline polyester in a toner cross section of the toner of the present invention by an electron beam transmission microscope. 3 is a crystal length distribution diagram of a crystalline polyester in a cross section of a toner of the present invention. FIG.

  In the toner of the present invention, it is important that the crystalline polyester is present as crystals of 100 nm or more and 250 nm or less that are observed in a needle shape in the cross section of the toner. It has been confirmed that a toner sufficiently containing crystalline polyester of this size and this crystalline state has significantly improved anti-offset performance compared to a toner having the same low-temperature fixability that does not contain crystalline polyester. It was.

  When the present inventors examined the mechanism, it was confirmed by experiments that the same release effect as that of the hydrocarbon wax used as the release agent for the crystalline polyester was exhibited. It is considered that the crystalline polyester itself exhibits a tearing-off effect when the polyester crystals that are seen as needles of an appropriate size are melted in the fixing nip.

  It was also found that when the release agent was contained in the toner, the amount of release agent exposed on the toner melt surface increased, and it was confirmed that the effect of the release agent was improved.

  On the other hand, when the crystalline domain of the crystalline polyester becomes too large, the release agent may be ununiformly exposed and the hot offset resistance may not be improved. Conversely, even if the crystal domain length is too short, the effect of improving the offset performance was not observed. This is probably because the amount of the above-mentioned crystalline polyester itself for crying was insufficient and the release effect could not be exhibited.

  In addition, the present invention is a toner having a low content of a commonly used release agent such as hydrocarbon wax, or a wax release agent that is stored in a high temperature and high humidity environment for a long time to deteriorate the dispersion state. The anti-offset effect was remarkable when the effect of the wax release agent could not be expected, such as toner.

  From the above experimental results, it has been found that there is a toner in which the crystalline polyester is in an optimum crystalline state for exhibiting the releasing effect, and the present invention has been achieved.

  The toner of the present invention is characterized by containing a binder resin, a colorant, and a release agent (hereinafter referred to as wax), and further containing a crystalline resin as a fixing aid.

<Amorphous resin A / B configuration>
The toner of the present invention contains, as a binder resin, a polyester resin A having an aromatic diol as a main component and a small weight average molecular weight and a polyester resin B having an aromatic diol as a main component and a large weight average molecular weight. Is preferred.

  By using two polyesters with different weight average molecular weights as the binder resin, the low temperature fixability of the toner is improved by the polyester having a low weight average molecular weight, and the hot offset resistance of the toner is improved by the polyester having a high weight average molecular weight. Can do.

  The sum of the content of the polyester resin A and the polyester resin B with respect to 100 parts by mass of the binder resin is preferably 90 parts by mass or more.

  Further, in order to increase the proportion of crystalline polyester crystals that are present individually in the toner and to obtain higher offset resistance, it is preferable that the polyester resin is contained in an amount of 70% by mass or more based on the entire toner. .

  In the present invention, the ratio of the polyester resin B to the total amount of the polyester resin A and the polyester resin B is preferably 20% by mass to 40% by mass. When (B / A + B) is within this range, the balance between low-temperature fixability and hot offset resistance is good.

  Both polyester resin A and polyester resin B have a polyhydric alcohol unit and a polycarboxylic acid unit. In the present invention, the polyhydric alcohol unit is a component derived from the polyhydric alcohol component used in the condensation polymerization of polyester. In the present invention, the polyvalent carboxylic acid unit is a component derived from the polyvalent carboxylic acid used in the polyester polycondensation or its anhydride or lower alkyl ester.

  Both the polyester resin A and the polyester resin B of the present invention have a polyhydric alcohol unit and a polycarboxylic acid unit, and 90 mol of the polyhydric alcohol unit derived from the aromatic diol with respect to the total number of moles of the polyhydric alcohol unit. % Or more. If the polyhydric alcohol unit derived from the aromatic diol is less than 90 mol% with respect to the total number of moles of the polyhydric alcohol unit, the fog is deteriorated.

  Since the polyhydric alcohol unit of the polyester resin A has a structure derived from an aromatic diol common to the polyester resin B, it is easily compatible and the dispersibility of the polyester A and the polyester B is improved.

  Examples of the component derived from the aromatic diol include bisphenol represented by the formula (1) and derivatives thereof.

（式中、Ｒはエチレンまたはプロピレン基であり、ｘ、ｙはそれぞれ０以上の整数であり、かつ、ｘ＋ｙの平均値は０乃至１０である。）

(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.)

  Among them, it is preferable that R in the formula (1) of the polyester resin A and the polyester resin B is the same because they are easily compatible during melt kneading. Further, a propylene oxide adduct of bisphenol A in which both R are propylene groups and the average value of x + y is 2 or more and 4 or less is preferable from the viewpoint of charging stability.

<Amorphous resin B>
The polyester resin B of the present invention preferably contains 0.1 mol% or more and 10.0 mol% or less of a polyhydric alcohol unit derived from an oxyalkylene ether of a novolak type phenol resin with respect to the total number of moles of the polyhydric alcohol unit. .

  The oxyalkylene ether of the novolak type phenol resin has a trihydric or higher alcoholic hydroxyl value and reacts with the acid component to form a flexible cross-linked structure with a wide network. Therefore, when the polyester resin B is mixed with the polyester A in the melt kneading step of the toner, the steric hindrance in the vicinity of the crosslinking point of the crosslinked structure of the polyester A is reduced, and the polyester B is easily entangled. As a result, the polyester resin B is well dispersed in the polyester resin A, the dispersibility of the crystalline polyester is also improved, and the crystalline polyester crystal tends to be neatly dispersed.

  The oxyalkylene ether of the novolac type phenol resin is a reaction product of the novolac type phenol resin and a compound having one epoxy ring in the molecule.

  Examples of the novolac type phenolic resin include hydrochloric acid, phosphoric acid, phosphoric acid, as described in the paragraph of Encyclopedia of Polymer Science and Technology (Interscience Publishers), Volume 10, page 1 Examples thereof include those produced by polycondensation from phenols and aldehydes using an inorganic acid such as sulfuric acid or an organic acid such as paratoluenesulfonic acid or oxalic acid or a metal salt such as zinc acetate as a catalyst. Examples of the phenols include phenols and substituted phenols having one or more hydrocarbon groups having 1 to 35 carbon atoms and / or halogen groups as substituents. Specific examples of the substituted phenol include cresol (ortho, meta or para), ethylphenol, nonylphenol, octylphenol, phenylphenol, styrenated phenol, isopropenylphenol, 3-chlorophenol, 3-bromophenol, 3, 5-xylenol, 2,4-xylenol, 2,6-xylenol, 3,5-dichlorophenol, 2,4-dichlorophenol, 3-chloro-5-methylphenol, dichloroxylenol, dibromoxylenol, Examples include 2,4,5-trichlorophenol and 6-phenyl-2-chlorophenol. Two or more phenols may be used in combination. In these, the substituted phenol substituted by the phenol and the hydrocarbon group is preferable, and especially phenol, cresol, t-butylphenol, and nonylphenol are preferable. Phenol and cresol are preferred in terms of imparting cost and offset resistance of the toner, and substituted phenols substituted with hydrocarbon groups typified by t-butylphenol and nonylphenol are preferred in terms of reducing the temperature dependence of the toner charge amount. preferable. Examples of aldehydes include formalin (formaldehyde solutions with various concentrations), paraformaldehyde, trioxane, hexamethylenetetramine and the like. The number average molecular weight of the novolak type phenol resin is usually 300 to 8000, preferably 450 to 3000, and more preferably 400 to 2000.

  The number-average number of phenolic nuclei in the novolak type phenolic resin is usually 3 to 60, preferably 3 to 20, and more preferably 4 to 15. The softening point (JIS K2531; ring and ball method) is usually 40 to 180 ° C., preferably 40 to 150 ° C., more preferably 50 to 130 ° C. If the softening point is less than 40 ° C., it will be blocked at room temperature and difficult to handle. On the other hand, when the softening point exceeds 180 ° C., gelation is caused in the production process of the polyester resin, which is not preferable.

  Specific examples of the compound having one epoxy ring in the molecule include ethylene oxide (EO), 1,2-propylene oxide (PO), 1,2-butylene oxide, 2,3-butylene oxide, styrene oxide, epichlorohydrin. Etc. Further, aliphatic monohydric alcohol having 1 to 20 carbon atoms or glycidyl ether of monohydric phenol can also be used. Of these, EO and / or PO are preferred. The number of moles of the compound having one epoxy ring in the molecule relative to 1 mole of the novolak type phenol resin is usually 1 to 30 moles, preferably 2 to 15 moles, more preferably 2.5 to 10 moles. Further, the average addition mole number of the compound having one epoxy ring in the molecule to one phenolic hydroxyl group in the novolak type phenol resin is usually 0.1 to 10 mol, preferably 0.1 to 4 mol, more preferably. 0.2 to 2 moles.

  The structure of the oxyalkylene ether of the novolak type phenol resin particularly preferably used in the present invention is illustrated.

（式中Ｒはエチレンまたはプロピレン基であり、ｘは０以上の数で、ｙ１乃至ｙ３は０以上の同一又は異なった数である。）

(In the formula, R is an ethylene or propylene group, x is a number of 0 or more, and y1 to y3 are the same or different numbers of 0 or more.)

  The number average molecular weight of the oxyalkylene ether of the novolak type phenol resin is usually 300 to 10,000, preferably 350 to 5,000, more preferably 450 to 3,000. If the number average molecular weight is less than 300, sufficient hot offset resistance of the toner cannot be secured, and if it exceeds 10,000, gelation is caused in the production process of the polyester resin A, which is not preferable.

  The hydroxyl value (total of alcoholic and phenolic hydroxyl groups) of the oxyalkylene ether of the novolak type phenol resin is usually 10 to 550, preferably 50 to 500, and more preferably 100 to 450 mgKOH / g. Of the hydroxyl values, the phenolic hydroxyl value is usually 0 to 500 mgKOH / g, preferably 0 to 350 mgKOH / g, more preferably 5 to 250 mgKOH / g.

  An example of a method for producing an oxyalkylene ether of a novolak-type phenol resin is as follows: by adding a compound having one epoxy ring in a molecule to a novolak-type phenol resin in the presence of a catalyst (basic catalyst or acidic catalyst) as necessary. can get. The reaction temperature is usually 20 to 250 ° C., preferably 70 to 200 ° C., and the reaction can be carried out under normal pressure, under pressure, or under reduced pressure. The reaction can also be carried out in the presence of a solvent (for example, xylene, dimethylformamide, etc.) or other dihydric alcohols and / or other trihydric or higher alcohols.

  When the polyhydric alcohol unit derived from the oxyalkylene ether of the novolak-type phenol resin of the polyester resin B is less than 0.1 mol%, the above-described flexible cross-linked structure portion having a wide network is reduced. Therefore, the dispersibility between the polyester resin A and the crystalline polyester is hardly improved. On the other hand, if it exceeds 10 mol%, the gel content of the polyester resin B is excessively increased, so that the polyester A and the crystalline polyester are hardly mixed at the time of melt-kneading, and the dispersibility of the crystalline polyester is hardly improved.

  As the component constituting the polyhydric alcohol unit of the polyester resin B, in addition to the aromatic diol and the oxyalkylene ether of the novolac type phenol resin, the following polyhydric alcohol components can be used as necessary. . Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1, 6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbit, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol , Dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butant Ol, trimethylol ethane, trimethylol propane, 1,3,5-trihydroxy methyl benzene.

  The polyester resin B of the present invention is derived from an aliphatic dicarboxylic acid having a straight chain hydrocarbon having 4 to 16 carbon atoms as a main chain and having carboxyl groups at both ends with respect to the total number of moles of polyvalent carboxylic acid units. It is preferable because the dispersibility between resins containing 15 mol% or more and 50 mol% or less of polyvalent carboxylic acid units is improved.

  An aliphatic dicarboxylic acid having a straight chain hydrocarbon having 4 to 16 carbon atoms as a main chain and having carboxyl groups at both ends has a straight chain hydrocarbon structure in the main chain of the polyester when reacted with an alcohol component. Therefore, the main chain has a partially flexible structure. Therefore, in the toner melt-kneading step, the polyester resin A having a low softening point is mixed with the polyester resin B having a high softening point starting from this flexible structure, and entangled with the main chain of the cross-linking point polyester resin A to achieve dispersibility. And the dispersibility of the crystalline polyester is also improved.

  Aliphatic dicarboxylic acids having a straight chain hydrocarbon having 4 to 16 carbon atoms and having carboxyl groups at both ends are, for example, alkyl such as adipic acid, azelaic acid, sebacic acid, tetradecanedioic acid and octadecanedioic acid. Examples thereof include dicarboxylic acids, anhydrides thereof, and lower alkyl esters. In addition, a compound having a structure in which a part of the main chain is branched by an alkyl group such as a methyl group, an ethyl group, or an octyl group, or an alkylene group. Carbon number of this linear hydrocarbon becomes like this. Preferably it is 4-12, More preferably, it is 4-10.

  Examples of other polyvalent carboxylic acid units contained in the polyester resin B include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, or anhydrides thereof; alkyl groups or alkenyl groups having 6 to 18 carbon atoms. Substituted succinic acids or anhydrides thereof; unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid or anhydrides thereof. Among these, carboxylic acid having an aromatic ring such as terephthalic acid, isophthalic acid, trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid and their anhydrides or their derivatives are likely to improve hot offset resistance. Therefore, it is preferably used.

<Amorphous resin A>
The polyester resin A of the present invention has a polyhydric alcohol unit and a polycarboxylic acid unit, and contains 90 mol% or more of a polyhydric alcohol unit derived from an aromatic diol with respect to the total number of moles of the polyhydric alcohol unit. It is characterized by. If the polyhydric alcohol unit derived from the aromatic diol is less than 90 mol% with respect to the total number of moles of the polyhydric alcohol unit, the fog is deteriorated. In order to ensure compatibility with the polyester B in the present invention, it is preferably 95 mol% or more, and more preferably 100 mol%.

  As components other than the aromatic diol that forms the polyhydric alcohol unit of the polyester resin B, the following polyhydric alcohol components can be used. Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1, 6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbit, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol , Dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butant Ol, trimethylol ethane, trimethylol propane, 1,3,5-trihydroxy methyl benzene.

  The polyester resin A of the present invention is characterized by containing 90 mol% or more of a polyvalent carboxylic acid unit derived from an aromatic dicarboxylic acid or a derivative thereof based on the total number of moles of the polyvalent carboxylic acid unit.

  When the polyvalent carboxylic acid unit derived from the aromatic dicarboxylic acid or its derivative is in the above range, the compatibility with the polyester A is improved, and density fluctuations and fogging after long-time printing can be suppressed.

  Aromatic dicarboxylic acids or derivatives thereof include aromatic dicarboxylic acids such as phthalic acid, isophthalic acid and terephthalic acid, or anhydrides thereof.

  Further, when the polyvalent carboxylic acid unit derived from the aliphatic dicarboxylic acid or its derivative is contained in an amount of 0.1 mol% or more and 10.0 mol% or less with respect to the total number of moles of the polyvalent carboxylic acid unit, the low temperature fixability of the toner is further improved. It is preferable because it improves.

  Examples of the aliphatic dicarboxylic acid or derivatives thereof include alkyldicarboxylic acids such as succinic acid, adipic acid, sebacic acid and azelaic acid or anhydrides thereof; succinic acid substituted with an alkyl group or alkenyl group having 6 to 18 carbon atoms, or Examples thereof include unsaturated dicarboxylic acids such as fumaric acid, maleic acid and citraconic acid, or anhydrides thereof. Of these, succinic acid, adipic acid, fumaric acid, acid anhydrides thereof, and lower alkyl esters are preferably used.

  Examples of other polyvalent carboxylic acid units include trivalent or tetravalent carboxylic acids such as trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, and anhydrides thereof.

<Other binder resins>
As the binder resin used in the toner of the present invention, in addition to the above polyester resin A and polyester resin B, the following resins may be used for the purpose of improving pigment dispersibility and improving toner charging stability and blocking resistance. It is also possible to add the polymer in an amount that does not impair the effects of the present invention.

  Examples of other resins used for the binder resin of the toner of the present invention include the following resins. Styrene such as polystyrene, poly-p-chlorostyrene, polyvinyltoluene, and homopolymers thereof; styrene-p-chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene -Acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether Styrene copolymers such as copolymers, styrene-vinyl methyl ketone copolymers, styrene-acrylonitrile-indene copolymers; polyvinyl chloride, phenol resins, natural modified phenol resins, natural resin modified maleic resins, acrylic resins , Methacrylic tree , Polyvinyl acetate, silicone resins, polyester resins, polyurethane, polyamide resins, furan resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone - indene resins, petroleum resins, and the like.

<Release agent (wax)>
Examples of the wax used in the toner of the present invention include the following. Low molecular weight polyethylene, low molecular weight polypropylene, alkylene copolymer, hydrocarbon wax such as microcrystalline wax, paraffin wax, Fischer-Tropsch wax; oxide of hydrocarbon wax such as oxidized polyethylene wax or block copolymer thereof; Waxes mainly composed of fatty acid esters such as carnauba wax; those obtained by partially or fully deoxidizing fatty acid esters such as deoxidized carnauba wax. Furthermore, the following are mentioned. Saturated linear fatty acids such as palmitic acid, stearic acid and montanic acid; unsaturated fatty acids such as brassic acid, eleostearic acid and valinalic acid; stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, Saturated alcohols such as sil alcohols; polyhydric alcohols such as sorbitol; fatty acids such as palmitic acid, stearic acid, behenic acid, montanic acid, and stearyl alcohol, aralkyl alcohol, behenyl alcohol, carnauvyl alcohol, seryl alcohol, Esters with alcohols such as sil alcohols; Fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide; Methylene bis stearic acid amide, ethylene biscapric acid Saturated fatty acid bisamides such as amide, ethylene bis lauric acid amide, hexamethylene bis stearic acid amide; ethylene bis oleic acid amide, hexamethylene bis oleic acid amide, N, N 'dioleyl adipic acid amide, N, N' dioleyl Unsaturated fatty acid amides such as sebacic acid amides; aromatic bisamides such as m-xylene bis-stearic acid amide, N, N ′ distearyl isophthalic acid amide; calcium stearate, calcium laurate, zinc stearate, magnesium stearate Aliphatic metal salts such as those commonly referred to as metal soaps; waxes grafted to aliphatic hydrocarbon waxes using vinylic monomers such as styrene and acrylic acid; fatty acids such as behenic acid monoglycerides Alcohol Partial ester; methyl ester compounds having hydroxyl groups obtained by hydrogenation of vegetable fats and oils.

  Among these waxes, hydrocarbon waxes such as paraffin wax and Fischer-Tropsch wax or fatty acid ester waxes such as carnauba wax are preferable from the viewpoint of improving low-temperature fixability and hot offset resistance. In the present invention, a hydrocarbon wax is more preferable in that the hot offset resistance is further improved.

  In the present invention, the wax is preferably used in an amount of 1 to 20 parts by mass per 100 parts by mass of the binder resin.

  Moreover, in the endothermic curve at the time of temperature rise measured with a differential scanning calorimetry (DSC) apparatus, the peak temperature of the maximum endothermic peak of the wax is preferably 45 ° C. or higher and 140 ° C. or lower. It is preferable that the peak temperature of the maximum endothermic peak of the wax is within the above range because both the storage stability of the toner and the hot offset resistance can be achieved.

<Colorant>
Examples of the colorant that can be contained in the toner include the following.

  Examples of the black colorant include carbon black; those prepared by using a yellow colorant, a magenta colorant, and a cyan colorant and adjusting the color to black. As the colorant, a pigment may be used alone, but it is more preferable from the viewpoint of the image quality of a full-color image to improve the sharpness by using a dye and a pigment together.

  Examples of the magenta toner pigment include the following. C. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48: 2, 48: 3, 48: 4, 49, 50, 51, 52, 53, 54, 55, 57: 1, 58, 60, 63, 64, 68, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 146, 147, 150, 163, 184, 202, 206, 207, 209, 238, 269, 282; I. Pigment violet 19; C.I. I. Bat red 1, 2, 10, 13, 15, 23, 29, 35.

  Examples of the magenta toner dye include the following. C. I. Solvent Red 1, 3, 8, 23, 24, 25, 27, 30, 49, 81, 82, 83, 84, 100, 109, 121; I. Disper thread 9; I. Solvent violet 8, 13, 14, 21, 27; C.I. I. Oil-soluble dyes such as Disper Violet 1, C.I. I. B. Basic Red 1, 2, 9, 12, 13, 14, 15, 17, 18, 22, 23, 24, 27, 29, 32, 34, 35, 36, 37, 38, 39, 40; I. Basic dyes such as Basic Violet 1, 3, 7, 10, 14, 15, 21, 25, 26, 27, 28.

  Examples of the cyan toner pigment include the following. C. I. Pigment blue 2, 3, 15: 2, 15: 3, 15: 4, 16, 17; I. Bat Blue 6; C.I. I. Acid Blue 45, a copper phthalocyanine pigment in which 1 to 5 phthalimidomethyl groups are substituted on the phthalocyanine skeleton.

  Examples of cyan toner dyes include C.I. I. There is Solvent Blue 70.

  Examples of the yellow toner pigment include the following. C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 83, 93, 94, 95, 97, 109, 110, 111, 120, 127, 128, 129, 147, 151, 154, 155, 168, 174, 175, 176, 180, 181, 185; I. Bat yellow 1, 3, 20

  Examples of the dye for yellow toner include C.I. I. There is Solvent Yellow 162.

  The amount of the colorant used is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the binder resin.

<Charge control agent>
The toner may contain a charge control agent as necessary. As the charge control agent contained in the toner, known ones can be used. In particular, a metal compound of an aromatic carboxylic acid that is colorless, has a high toner charging speed, and can stably maintain a constant charge amount is preferable.

  Negative charge control agents include salicylic acid metal compounds, naphthoic acid metal compounds, dicarboxylic acid metal compounds, polymeric compounds having sulfonic acid or carboxylic acid in the side chain, sulfonates or sulfonated compounds in the side chain. Examples thereof include a polymer compound, a polymer compound having a carboxylate or a carboxylic acid ester in the side chain, a boron compound, a urea compound, a silicon compound, and calixarene. Examples of the positive charge control agent include quaternary ammonium salts, polymer compounds having the quaternary ammonium salt in the side chain, guanidine compounds, and imidazole compounds. The charge control agent may be added internally or externally to the toner particles. The addition amount of the charge control agent is preferably 0.2 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the binder resin.

<Crystalline resin>
The toner of the present invention contains a crystalline polyester as a fixing aid.

  In the toner of the present invention, the crystalline polyester contained in the toner particles is a monomer composition containing an aliphatic diol having 2 to 22 carbon atoms and an aliphatic dicarboxylic acid having 2 to 22 carbon atoms as main components. Can be obtained by polycondensation reaction.

  The aliphatic diol having 2 to 22 carbon atoms (more preferably 8 to 12 carbon atoms) is not particularly limited, but is preferably a chain (more preferably linear) aliphatic diol, for example, , Ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, dipropylene glycol, 1,4-butanediol, 1,4-butadiene glycol, trimethylene glycol, tetramethylene glycol, Examples include pentamethylene glycol, hexamethylene glycol, octamethylene glycol, nonamethylene glycol, decamethylene glycol, and neopentyl glycol. Of these, linear aliphatic groups such as ethylene glycol, diethylene glycol, 1,4-butanediol, and 1,6-hexanediol, and α, ω-diol are particularly preferred.

  Among the alcohol components, preferably 50% by mass or more, more preferably 70% by mass or more is an alcohol selected from aliphatic diols having 2 to 22 carbon atoms.

  In the present invention, a polyhydric alcohol monomer other than the aliphatic diol can also be used. Among the polyhydric alcohol monomers, examples of the dihydric alcohol monomer include aromatic alcohols such as polyoxyethylenated bisphenol A and polyoxypropylenated bisphenol A; 1,4-cyclohexanedimethanol and the like. Among the polyhydric alcohol monomers, trihydric or higher polyhydric alcohol monomers include aromatic alcohols such as 1,3,5-trihydroxymethylbenzene; pentaerythritol, dipentaerythritol, tripentaerythritol. 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerin, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane and the like Group alcohol and the like.

  Furthermore, in this invention, you may use monohydric alcohol to such an extent that the characteristic of crystalline polyester is not impaired. Examples of the monovalent alcohol include monofunctional groups such as n-butanol, isobutanol, sec-butanol, n-hexanol, n-octanol, lauryl alcohol, 2-ethylhexanol, decanol, cyclohexanol, benzyl alcohol, and dodecyl alcohol. And alcohol.

  On the other hand, the aliphatic dicarboxylic acid having 2 to 22 carbon atoms (more preferably 6 to 14 carbon atoms) is not particularly limited, but is a chain (more preferably linear) aliphatic dicarboxylic acid. Is preferred. Specific examples include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, speric acid, glutaconic acid, azelaic acid, sebacic acid, nonanedicarboxylic acid, decanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid, Examples include maleic acid, fumaric acid, mesaconic acid, citraconic acid, and itaconic acid, and those obtained by hydrolyzing these acid anhydrides or lower alkyl esters.

  In the present invention, among the carboxylic acid components, preferably 50% by mass or more, more preferably 70% by mass or more is a carboxylic acid selected from aliphatic dicarboxylic acids having 2 to 22 carbon atoms.

  In the present invention, a polyvalent carboxylic acid other than the aliphatic dicarboxylic acid having 2 to 22 carbon atoms may be used. Among the other polyvalent carboxylic acid monomers, divalent carboxylic acids include aromatic carboxylic acids such as isophthalic acid and terephthalic acid; n-dodecyl succinic acid, n-dodecenyl succinic aliphatic carboxylic acid; cyclohexane dicarboxylic acid Examples thereof include alicyclic carboxylic acids such as acids, and these acid anhydrides or lower alkyl esters are also included. Among the other carboxylic acid monomers, trivalent or higher polyvalent carboxylic acids include 1,2,4-benzenetricarboxylic acid (trimellitic acid), 2,5,7-naphthalenetricarboxylic acid, Aromatic carboxylic acids such as 2,4-naphthalenetricarboxylic acid and pyromellitic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2 -Aliphatic carboxylic acids such as methylenecarboxypropane, and derivatives of these acid anhydrides or lower alkyl esters are also included.

  Furthermore, in this invention, you may contain monovalent carboxylic acid to such an extent that the characteristic of crystalline polyester is not impaired. Examples of the monovalent carboxylic acid include benzoic acid, naphthalenecarboxylic acid, salicylic acid, 4-methylbenzoic acid, 3-methylbenzoic acid, phenoxyacetic acid, biphenylcarboxylic acid, acetic acid, propionic acid, butyric acid, octanoic acid, decanoic acid, Examples thereof include monocarboxylic acids such as dodecanoic acid and stearic acid.

  The crystalline polyester in the present invention can be produced according to an ordinary polyester synthesis method. For example, the above-mentioned carboxylic acid monomer and alcohol monomer are esterified or transesterified, and then subjected to a polycondensation reaction in accordance with a conventional method under reduced pressure or by introducing nitrogen gas. Crystalline polyester can be obtained.

  The esterification or transesterification reaction can be performed using a normal esterification catalyst or transesterification catalyst such as sulfuric acid, titanium butoxide, dibutyltin oxide, manganese acetate, and magnesium acetate, if necessary.

  The polycondensation reaction can be carried out using a conventional polymerization catalyst, for example, a known catalyst such as titanium butoxide, dibutyltin oxide, tin acetate, zinc acetate, tin disulfide, antimony trioxide, germanium dioxide. . The polymerization temperature and the catalyst amount are not particularly limited, and may be determined appropriately.

  In the esterification or transesterification reaction or polycondensation reaction, all monomers are charged together to increase the strength of the resulting crystalline polyester, or divalent monomers are first reacted to reduce low molecular weight components. Then, a method of adding a trivalent or higher monomer and reacting the monomer may be used.

<Inorganic particles (mainly external additives)>
The toner of the present invention may contain inorganic fine particles as necessary. The inorganic fine particles may be added internally to the toner particles or may be mixed with the toner particles as an external additive. As the external additive, inorganic fine powders such as silica, titanium oxide and aluminum oxide are preferable. The inorganic fine powder is preferably hydrophobized with a hydrophobizing agent such as a silane compound, silicone oil or a mixture thereof.

As an external additive for improving fluidity, an inorganic fine powder having a specific surface area of 50 m ² / g or more and 400 m ² / g or less is preferable. For stabilization of durability, the specific surface area is 10 m ² / g or more and 50 m or less. An inorganic fine powder of ² / g or less is preferable. In order to achieve both improvement in fluidity and stabilization of durability, an inorganic fine powder having a specific surface area in the above range may be used in combination.

  The external additive is preferably used in an amount of 0.1 to 10.0 parts by mass with respect to 100 parts by mass of the toner particles. For mixing the toner particles and the external additive, a known mixer such as a Henschel mixer can be used.

<Developer>
The toner of the present invention can also be used as a one-component developer, but in order to further improve dot reproducibility, it can be mixed with a magnetic carrier and used as a two-component developer. Is preferable in that it is obtained.

  Examples of the magnetic carrier include iron powder whose surface is oxidized, non-oxidized iron powder, metal particles such as iron, lithium, calcium, magnesium, nickel, copper, zinc, cobalt, manganese, chromium, rare earth, and the like Magnetic material dispersed resin carriers (so-called resin carriers) containing magnetic materials such as alloy particles, oxide particles, ferrite, and the like, and magnetic materials and binder resins that hold the magnetic materials in a dispersed state are generally known. Things can be used.

  When the toner of the present invention is mixed with a magnetic carrier and used as a two-component developer, the carrier mixing ratio at that time is 2% by mass or more and 15% by mass or less, preferably as a toner concentration in the two-component developer. In general, good results are obtained when the content is from 4% by mass to 13% by mass.

<Manufacturing method>
As a method for producing toner particles, since it is necessary to melt and knead the binder resin, the colorant, and the wax, the binder resin, the colorant, and the wax are melt-kneaded, and the kneaded product is cooled, A pulverization method of pulverization and classification is preferred.

  Hereinafter, a toner manufacturing procedure using the pulverization method will be described.

  In the raw material mixing step, as a material constituting the toner particles, for example, a predetermined amount of other components such as a binder resin, a wax, a colorant, and a charge control agent as necessary are mixed and mixed. Examples of the mixing apparatus include a double-con mixer, a V-type mixer, a drum-type mixer, a super mixer, a Henschel mixer, a Nauta mixer, and a mechano-hybrid (manufactured by Nippon Coke Industries, Ltd.).

  Next, the mixed material is melt-kneaded to disperse wax or the like in the binder resin. In the melt-kneading process, a batch kneader such as a pressure kneader or a Banbury mixer or a continuous kneader can be used, and a single-screw or twin-screw extruder has become the mainstream because of the advantage of continuous production. ing. For example, KTK type twin screw extruder (manufactured by Kobe Steel Co., Ltd.), TEM type twin screw extruder (manufactured by Toshiba Machine Co., Ltd.), PCM kneader (manufactured by Ikekai Tekko), twin screw extruder (manufactured by K.C.K. ), Co-kneader (manufactured by Buss), kneedex (manufactured by Nippon Coke Industries Co., Ltd.), and the like. Furthermore, the resin composition obtained by melt-kneading may be rolled with two rolls or the like and cooled with water or the like in the cooling step.

  Next, the cooled product of the resin composition is pulverized to a desired particle size in the pulverization step. In the pulverization step, for example, after coarse pulverization with a pulverizer such as a crusher, a hammer mill, or a feather mill, for example, a kryptron system (manufactured by Kawasaki Heavy Industries), a super rotor (manufactured by Nisshin Engineering), a turbo mill Finely pulverize with a turbomill (made by Turbo Industries) or air jet type fine pulverizer.

  Then, if necessary, classification such as inertial class elbow jet (manufactured by Nippon Steel & Mining Co., Ltd.), centrifugal classification turboplex (manufactured by Hosokawa Micron), TSP separator (manufactured by Hosokawa Micron), Faculty (manufactured by Hosokawa Micron) Classification using a machine or sieving machine to obtain a classified product (toner particles). Among these, Faculty (manufactured by Hosokawa Micron Corporation) is preferable from the viewpoint of improving the transfer efficiency because it can perform the spheroidizing treatment of toner particles simultaneously with the classification.

  Further, an external additive is applied to the surface of the toner particles as necessary. As a method of externally adding external additives, a predetermined amount of classified toner and various known external additives are blended, and a double-con mixer, V-type mixer, drum-type mixer, super mixer, Henschel mixer, Nauta mixer, mechano Examples thereof include a method of stirring and mixing using a mixing device such as a hybrid (manufactured by Nippon Coke Industries Co., Ltd.), Nobilta (manufactured by Hosokawa Micron Co., Ltd.) or the like as an external adder.

  A method for measuring various physical properties of toner and raw materials will be described below.

<Evaluation of crystalline state of crystalline polyester by TEM observation>
Cross-sectional observation of the toner with a transmission electron microscope (TEM) and evaluation of the crystalline polyester domain can be carried out as follows.

  By ruthenium dyeing the toner cross section, a crystalline polyester resin can be obtained as a clear contrast. The crystalline polyester resin is dyed weaker than the organic component constituting the inside of the toner. This is presumably because the infiltration of the dye material into the crystalline polyester resin is weaker than the organic component inside the toner due to a difference in density.

  Because the amount of ruthenium atoms varies depending on the intensity of staining, the strongly stained part has many of these atoms, the electron beam does not pass through, it becomes black on the observation image, and the part that is weakly stained is The electron beam is easily transmitted and becomes white on the observation image.

  Using an osmium plasma coater (filgen, OPC80T), the toner is coated with an Os film (5 nm) and a naphthalene film (20 nm) as a protective film, and embedded with a photo-curing resin D800 (JEOL). Using a sonic ultramicrotome (Leica, UC7), a toner cross section having a film thickness of 60 nm (or 70 nm) was prepared at a cutting speed of 1 mm / s.

  The obtained cross section was dyed for 15 minutes in a RuO4 gas 500 Pa atmosphere using a vacuum electron dyeing apparatus (filgen, VSC4R1H), and STEM observation was performed using TEM (JEOL, JEM2800).

  The STEM probe size was 1 nm, and the image size was 1024 × 1024 pixels.

  The obtained image is binarized (threshold 120/255 stage) by image processing software “Image-Pro Plus (Media Cybernetics)”.

  The obtained cross-sectional image before binarization is shown in FIG. As can be seen in FIG. 1, the crystalline domains of the crystalline polyester can be confirmed as black bars, and the obtained images are binarized to extract the crystalline domains and measure their sizes. When cross-sectional observation is performed on 20 randomly selected toners, the lengths of the major axes and minor axes of the crystalline domains of the crystalline polyester whose length can be measured are all measured, and the length distribution is obtained. In the obtained long axis length distribution, the ratio of the number of crystal domains of 100 nm to 250 nm to the total number is obtained. Similarly, for the short axis length distribution, the ratio of the number of crystal domains of 5 nm to 15 nm with respect to the total number is obtained.

  Here, as shown in FIG. 2, the major axis length of the crystalline domain of the crystalline polyester is the longest distance (a in FIG. 2) in the crystal domain of the cross-sectional image, and the minor axis length is the center of the crystal major axis. This is the shortest distance (b in FIG. 2) at the point position.

  In the present invention, the shape of the crystal domain that is seen in a needle shape in the toner cross section is effective for hot offset, and the major axis has a certain size of a certain level of 100 nm to 250 nm or more so that it can be released from the fixing member. In particular, it can exhibit its properties.

  The mechanism of the release effect at this time is not completely clarified, but it can be explained by the “crying” effect of the material. “Cleaving” is an effect in which a release material exists at a predetermined interface, and the release material itself is cracked in two directions to protect the material (toner) desired to be released and not adhere to the mold (fixing member). . The requirement for the release material here is that it has a lower viscosity than the main binder resin of the toner body to be separated at the temperature at which the release effect is to be exerted, and the component of the material to be released from the release material, particularly in the toner It is mentioned that a coloring material is not included in the release material.

  Crystals of crystalline polyester in the toner have characteristics satisfying these requirements, and it is considered that a release effect can be exhibited. In order to further exhibit the mold release effect due to this crying separation, it is considered that an aggregate amount of a certain amount or more is necessary and there is an optimum crystal size.

  However, recent toners contain a wax release material with a higher release effect. If the crystal domain is too large, the effect of the wax release material is inhibited, and the toner release effect is reduced in total. There seems to be.

  It is presumed that the crystalline polyester crystal domain is likely to be exposed in the fixing device because the crystal which looks like a long and narrow needle in the cross section of the toner is easily melted by heat and is not easily caught by the toner binder resin.

  The needle shape in the present invention is an elongated shape having a high straightness, a minor axis length of 25 nm or less, an aspect ratio of 4 or more, and a minor axis direction in both major axis directions of the crystal. When the center points are connected by a straight line, the crystal outline deviation from the straight line is defined as a shape within 100% of the crystal minor axis length.

  FIG. 3 shows the number distribution of the lengths of the major axes of the crystalline polyester crystals observed in a needle shape in the toner cross section. In contrast to the long-axis length distribution of the crystalline polyester contained in the toner of the comparative example indicated by the broken line, the toner of the embodiment of the present invention indicated by the solid line has many crystals having a length of 100 nm to 250 nm. Long axis length distribution. The crystal having a length of 100 nm to 250 nm has such a size that the releasing effect upon fixing by the crystalline polyester itself can be maximized. In the toner of the present invention, among the total number of crystalline polyester crystals observed in a needle shape in the cross section of the toner, 30% or more of the crystal cross section having a size of 100 nm to 250 nm is present, thereby preventing hot offset. An excellent toner can be obtained.

  Furthermore, it is preferable that the number distribution has a major axis length number peak in the range of 60 nm to 250 nm in the number distribution because the effect of hot offset resistance is further improved. By increasing the proportion of crystals having a length equal to or greater than 60 nm or less than 250 nm, the adhesive force between the toner melting surface and the fixing member surface during fixing tends to be uniform, and there is no uneven hot offset resistance. This is considered to be obtained.

  Further, the crystalline polyester has a lower volume resistance than the amorphous resin, and the chargeability of the toner can be changed by changing the presence state in the toner. In the distribution of the length of the short axis of the crystalline polyester crystal of the present invention, when the number ratio of needle-like crystals of 5 nm or more and 15 nm or less is 90% by number or more, the rising speed of toner charging is improved in a low humidity environment, and the image It is preferable because the time required for preparation for charging the toner is shortened by idling of the developing device at the time of formation.

<Measurement method of weight average molecular weight of resin>
The molecular weight distribution of the THF soluble part of the resin is measured by gel permeation chromatography (GPC) as follows.

First, the toner is dissolved in tetrahydrofuran (THF) at room temperature over 24 hours. The obtained solution is filtered through a solvent-resistant membrane filter “Maescho Disc” (manufactured by Tosoh Corporation) having a pore diameter of 0.2 μm to obtain a sample solution. The sample solution is adjusted so that the concentration of the component soluble in THF is about 0.8% by mass. Using this sample solution, measurement is performed under the following conditions.
Apparatus: HLC8120 GPC (detector: RI) (manufactured by Tosoh Corporation)
Column: Seven series of Shodex KF-801, 802, 803, 804, 805, 806, 807 (manufactured by Showa Denko KK)
Eluent: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Oven temperature: 40.0 ° C
Sample injection volume: 0.10 ml

  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 glass transition temperature (Tg) of resin>
The glass transition temperature Tg of the resin is measured in accordance with 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 5 mg of resin is precisely weighed and placed in an aluminum pan, and an empty aluminum pan is used as a reference, and the temperature rising rate is 10 ° C./min between a measurement range of 30 to 200 ° C. Measure with. The temperature is raised to 180 ° C. and held for 10 minutes, then the temperature is lowered to 30 ° C., and then the temperature is raised again. In the second temperature raising process, a specific heat change is obtained in the temperature range of 30 to 100 ° C. At this time, the intersection of the intermediate point line of the baseline before and after the change in specific heat and the differential heat curve is defined as the glass transition temperature (Tg) of the resin.

<Measurement of DSC endotherm (ΔH) of wax and CPES>
The content of the crystalline polyester crystals and the wax release agent in the toner can be measured by an endothermic amount ΔH measured by a suggested calorimetric analysis (DSC).

The peak temperature (Tp) of the maximum endothermic peak of the toner or the like (toner, crystalline polyester) in the present invention is measured using DSC Q1000 (manufactured by TA Instruments) under the following conditions.
Temperature increase rate: 10 ° C / min
Measurement start temperature: 20 ° C
Measurement end temperature: 180 ° C

  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 5 mg of a sample is precisely weighed, placed in a silver pan, and measured once. A silver empty pan is used as a reference.

  When using toner as a sample, if the maximum endothermic peak (maximum endothermic peak derived from the binder resin) does not overlap with the endothermic peaks of resins other than wax and crystalline resin, the endothermic amount of the maximum endothermic peak obtained Is treated as the endothermic amount of the maximum endothermic peak derived from the wax and the crystalline resin. On the other hand, when the toner is used as a sample, if the endothermic peak of the resin other than the wax and the binder resin overlaps with the maximum endothermic peak of the binder resin, the endothermic amount derived from the resin other than the wax and the binder resin is calculated. It is necessary to subtract from the endothermic amount of the maximum endothermic peak obtained.

  The maximum endothermic peak means a peak where the endothermic amount is maximum when there are a plurality of peaks. Further, the endothermic amount (ΔH) of the maximum endothermic peak is obtained from the peak area by calculation using analysis software attached to the apparatus.

  In the present invention, when the endothermic amount (ΔH) of the crystal derived from the crystalline polyester is 1.0 J / g or more and 5.0 J / g or less, a remarkable hot offset resistance effect is obtained. If it is less than 1.0 J / g, the effect of hot offset resistance cannot be exhibited because the amount of crystalline polyester is insufficient. If it is greater than 5.0 J / g, the crystalline polyester crystals will aggregate, and conversely, there will be more portions where no crystalline polyester is present in the toner, and the effect of the crystalline polyester on resistance to hot offset will be difficult to manifest. Become.

  Further, regarding the total content of the crystalline polyester crystals and the wax release agent in the toner, the sum of the endothermic amounts ΔH (total DSC) measured by the suggested calorimetric analysis (DSC) of the crystalline polyester crystals and the wax release agent. The endothermic amount ΔH) is preferably 4.0 J / g or more and 7.0 J / g or less. When the sum of the heat absorption amounts ΔH is 4.0 J / g or more, the toner hardly adheres to the fixing member at the time of low-temperature fixing, and the low-temperature fixability is further improved. In addition, when the sum of the endothermic amounts ΔH is 7.0 J / g or less, it is possible to suppress a phenomenon in which the crystalline polyester crystal and the release agent are present at the same position on the toner surface and the release of each other is promoted. Therefore, adhesion to a toner charging member such as a carrier or a developing roller can be reduced, and the developability is hardly changed even during continuous use of image formation.

<Measurement of BET specific surface area of inorganic fine particles>
The BET specific surface area of the inorganic fine particles is measured according to JIS Z8830 (2001). A specific measurement method is as follows.

  As a measuring device, an “automatic specific surface area / pore distribution measuring device TriStar 3000 (manufactured by Shimadzu Corporation)” which employs a gas adsorption method by a constant volume method as a measuring method is used. Setting of measurement conditions and analysis of measurement data are performed using dedicated software “TriStar3000 Version 4.00” attached to the apparatus, and a vacuum pump, a nitrogen gas pipe, and a helium gas pipe are connected to the apparatus. The value calculated by the BET multipoint method using nitrogen gas as the adsorption gas is taken as the BET specific surface area of the inorganic fine particles in the present invention.

  The BET specific surface area is calculated as follows.

First, nitrogen gas is adsorbed onto the inorganic fine particles, and then the equilibrium pressure P (Pa) in the sample cell and the nitrogen adsorption amount Va (mol · g ⁻¹ ) of the external additive are measured. The relative pressure Pr, which is a value obtained by dividing the equilibrium pressure P (Pa) in the sample cell by the saturated vapor pressure Po (Pa) of nitrogen, is plotted on the horizontal axis, and the nitrogen adsorption amount Va (mol · g ⁻¹ ) is plotted on the vertical axis. The adsorption isotherm is obtained. Next, a monomolecular layer adsorption amount Vm (mol · g ⁻¹ ), which is an adsorption amount necessary for forming a monomolecular layer on the surface of the external additive, is determined by applying the following BET equation.
Pr / Va (1-Pr) = 1 / (Vm * C) + (C-1) * Pr / (Vm * C)
(Here, C is a BET parameter, which is a variable that varies depending on the measurement sample type, adsorbed gas type, and adsorption temperature.)

The BET equation is interpreted as a straight line with an inclination of (C-1) / (Vm × C) and an intercept of 1 / (Vm × C), where Pr is X axis and Pr / Va (1-Pr) is Y axis. Yes (this line is called a BET plot).
Straight line slope = (C-1) / (Vm × C)
Straight line intercept = 1 / (Vm × C)

  When the measured value of Pr and the measured value of Pr / Va (1-Pr) are plotted on a graph and a straight line is drawn by the least square method, the slope and intercept value of the straight line can be calculated. Vm and C can be calculated by solving the simultaneous equations of the slope and intercept using these values.

Furthermore, the BET specific surface area S (m ² / g) of the inorganic fine particles is calculated from the calculated Vm and the molecular occupation cross-sectional area (0.162 nm ² ) of the nitrogen molecule based on the following formula.
S = Vm × N × 0.162 × 10 ⁻¹⁸
(N is Avogadro's number (mole- ¹ ).)

  The measurement using this apparatus follows the “TriStar 3000 Instruction Manual V4.0” attached to the apparatus, and specifically, the measurement is performed according to the following procedure.

  Thoroughly weigh the tare of a dedicated glass sample cell (stem diameter 3/8 inch, volume about 5 ml) that has been thoroughly cleaned and dried. Then, about 0.1 g of an external additive is put into the sample cell using a funnel.

  The sample cell containing the inorganic fine particles is set in a “pretreatment device Bacrepprep 061 (manufactured by Shimadzu Corporation)” connected with a vacuum pump and a nitrogen gas pipe, and vacuum degassing is continued at 23 ° C. for about 10 hours. During vacuum deaeration, the inorganic fine particles are gradually deaerated while adjusting the valve so that the inorganic fine particles are not sucked into the vacuum pump. The pressure in the cell gradually decreases with deaeration and finally becomes about 0.4 Pa (about 3 mTorr). After completion of vacuum degassing, nitrogen gas is gradually injected to return the inside of the sample cell to atmospheric pressure, and the sample cell is removed from the pretreatment device. Then, the mass of the sample cell is precisely weighed, and the accurate mass of the external additive is calculated from the difference from the tare. At this time, the sample cell is covered with a rubber plug during weighing so that the external additive in the sample cell is not contaminated by moisture in the atmosphere.

  Next, a dedicated “isothermal jacket” is attached to the stem portion of the sample cell containing the inorganic fine particles. Then, a dedicated filler rod is inserted into the sample cell, and the sample cell is set in the analysis port of the apparatus. The isothermal jacket is a cylindrical member having an inner surface made of a porous material and an outer surface made of an impermeable material capable of sucking liquid nitrogen to a certain level by capillary action.

  Subsequently, the free space of the sample cell including the connection tool is measured. The free space is measured by measuring the volume of the sample cell using helium gas at 23 ° C., and then measuring the volume of the sample cell after cooling the sample cell with liquid nitrogen using helium gas. It is calculated by converting from the difference in volume. Further, the saturated vapor pressure Po (Pa) of nitrogen is automatically measured separately using a Po tube built in the apparatus.

  Next, after performing vacuum deaeration in the sample cell, the sample cell is cooled with liquid nitrogen while continuing the vacuum deaeration. Thereafter, nitrogen gas is gradually introduced into the sample cell to adsorb nitrogen molecules to the toner. At this time, since the adsorption isotherm is obtained by measuring the equilibrium pressure P (Pa) as needed, the adsorption isotherm is converted into a BET plot. Note that the points of the relative pressure Pr for collecting data are set to a total of 6 points of 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30. A straight line is drawn from the obtained measurement data by the least square method, and Vm is calculated from the slope and intercept of the straight line. Furthermore, using the value of Vm, the BET specific surface area of the inorganic fine particles is calculated as described above.

<Method for Measuring Weight Average Particle Size (D4) of Toner Particles>
The weight average particle diameter (D4) of the toner particles is measured with a precision particle size distribution measuring apparatus “Coulter Counter Multisizer 3” (registered trademark, manufactured by Beckman Coulter, Inc.) equipped with a 100 μm aperture tube. Measured data with 25,000 effective measurement channels using the dedicated software “Beckman Coulter Multisizer 3 Version 3.51” (manufactured by Beckman Coulter, Inc.) for condition setting and measurement data analysis 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, the number of measurements is 1 and the Kd value is “standard particles 10.0 μm” (Beckman Coulter 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 or more and 60 μm or less.

The specific measurement method is as follows.
(1) About 200 ml of the electrolytic 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 pH 7 precision measurement is used as a dispersant therein. 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-exchanged 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 Dissipation System Tetora 150” (manufactured by Nikkiki Bios Co., Ltd.) having an electrical output of 120 W. A predetermined amount of ion-exchanged water is put, 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) To the round bottom beaker of (1) installed in the sample stand, the electrolyte solution of (5) in which the toner is dispersed is dropped using a pipette, and the measurement concentration is adjusted to about 5%. . Measurement is performed until the number of measured particles reaches 50,000.
(7) The measurement 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).

<Production Example 1 of Amorphous Polyester Resin A>
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 71.9 parts by mass (0.20 mol; 100.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 26.8 parts by mass (0.16 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 1 hour while maintaining the temperature at 180 ° C. (second reaction step), and the polyester resin A1 having a weight average molecular weight (Mw) of 5000 Got.

<Production Example 2 of Amorphous Polyester Resin A>
Polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 71.9 parts by mass (0.20 mol; 100.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 26.8 parts by mass (0.16 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above-mentioned materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 1 hour while maintaining the temperature at 180 ° C. (second reaction step). Polyester resin A2 having a weight average molecular weight (Mw) of 4800 Got.

<Production Example 3 of Amorphous Polyester Resin A>
Polyoxybutylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 71.9 parts by mass (0.20 mol; 100.0 mol% with respect to the total number of polyhydric alcohols)
-Terephthalic acid: 26.8 parts by mass (0.16 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 1 hour while maintaining the temperature at 180 ° C. (second reaction step), and polyester resin A3 having a weight average molecular weight (Mw) of 5300 Got.

<Production Example 4 of Amorphous Polyester Resin A>
-2,2-bis (4-hydroxyphenyl) propane: 71.9 parts by mass (0.20 mol; 100.0 mol% with respect to the total number of polyhydric alcohols)
-Terephthalic acid: 26.8 parts by mass (0.16 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 4 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 1.3 parts by mass (0.01 mol; 4.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 1 hour while maintaining the temperature at 180 ° C. (second reaction step). Polyester resin A4 having a weight average molecular weight (Mw) of 4900 Got.

<Production Example 5 of Amorphous Polyester Resin A>
・ 2,2-bis (4-hydroxyphenyl) propane: 64.7 parts by mass (0.18 mol; 100.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 24.1 parts by mass (0.15 mol; 96.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide (esterification catalyst): 0.5 part by mass The above materials were weighed in a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introduction tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Further, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, then cooled to 180 ° C. and returned to atmospheric pressure (first reaction step).

-Acrylic acid: 0.2 parts by mass-Styrene: 8.2 parts by mass-2-Ethylhexyl acrylate: 1.6 parts by mass-Dibutyl peroxide (polymerization initiator): 1.5 parts by mass Was added dropwise over 1 hour and held for 1 hour (StAc conversion reaction step).
Trimellitic anhydride: 1.2 parts by mass (0.01 mol; 4.0 mol% based on the total number of polyvalent carboxylic acids)
Tert-butylcatechol (polymerization inhibitor): 0.1 part by mass Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is continued for 1 hour while maintaining the temperature at 160 ° C. (second Reaction step), an amorphous resin A5 having a weight average molecular weight (Mw) of 5000 was obtained.

<Amorphous Polyester Resin A Production Example 6>
Into a 5 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, 429 parts by mass of bisphenol A ethylene oxide 2 mol adduct, 329 parts by mass of bisphenol A propylene oxide 3 mol adduct, isophthalate 100 parts by weight of acid, 158 parts by weight of terephthalic acid and 2 parts by weight of dibutyltin oxide were reacted at 230 ° C. for 10 hours, further reacted at 10 to 15 mmHg for 5 hours, and then added with 30 parts by weight of trimellitic anhydride, 180 By reacting at 3 ° C. for 3 hours, amorphous polyester A6 was obtained. Amorphous polyester A6 had a glass transition point of 50 ° C. and a weight average molecular weight of 5,500.

<Amorphous polyester resin B production example 1>
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% based on the total number of polyhydric alcohols)
・ Novolac type phenol resin (ethylene oxide 5 mol adduct having about 5 cores): 4.4 parts by mass (0.01 mol; 3.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 15 hours while maintaining the temperature at 160 ° C. (second reaction step), and the polyester resin B1 having a weight average molecular weight (Mw) of 10,000. Got.

<Production Example 2 of Amorphous Polyester Resin B>
Polyoxyethylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% based on the total number of polyhydric alcohols)
・ Novolac type phenol resin (ethylene oxide 5 mol adduct having about 5 cores): 4.4 parts by mass (0.01 mol; 3.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 15 hours while maintaining the temperature at 160 ° C. (second reaction step), and the polyester resin B2 having a weight average molecular weight (Mw) of 110000 Got.

<Production Example 3 of Amorphous Polyester Resin B>
Polyoxybutylene (2.2) -2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% with respect to the total number of polyhydric alcohols)
・ Novolac type phenol resin (ethylene oxide 5 mol adduct having about 5 cores): 4.4 parts by mass (0.01 mol; 3.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is carried out for 15 hours while maintaining the temperature at 160 ° C. (second reaction step), and the polyester resin B3 having a weight average molecular weight (Mw) of 120,000. Got.

<Production Example 4 of Amorphous Polyester Resin B>
・ 2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% based on the total number of moles of polyhydric alcohol)
・ Novolac type phenol resin (ethylene oxide 5 mol adduct having about 5 cores): 4.4 parts by mass (0.01 mol; 3.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 15 hours while maintaining the temperature at 160 ° C. (second reaction step), and polyester resin B4 having a weight average molecular weight (Mw) of 110000. Got.

<Production Example 5 of Amorphous Polyester Resin B>
・ 2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% based on the total number of moles of polyhydric alcohol)
・ Novolac type phenol resin (ethylene oxide 5 mol adduct having about 5 cores): 4.4 parts by mass (0.01 mol; 3.0 mol% based on the total number of polyhydric alcohols)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is carried out for 15 hours while maintaining the temperature at 160 ° C. (second reaction step). Polyester resin B5 having a weight average molecular weight (Mw) of 90000 Got.

<Production Example 6 of Amorphous Polyester Resin B (without Hybrid H Form Adduct)>
・ 2,2-bis (4-hydroxyphenyl) propane: 68.2 parts by mass (0.19 mol; 97.0 mol% based on the total number of moles of polyhydric alcohol)
-Terephthalic acid: 15.0 parts by mass (0.09 mol; 55.0 mol% based on the total number of polycarboxylic acids)
Adipic acid: 6.0 parts by mass (0.04 mol; 25.0 mol% based on the total number of polyvalent carboxylic acids)
Titanium tetrabutoxide: 0.5 part by mass The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introducing tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 2 hours while stirring at a temperature of 200 ° C.

  Furthermore, the pressure in the reaction vessel was lowered to 8.3 kPa, maintained for 1 hour, and then returned to atmospheric pressure (first reaction step).

Trimellitic anhydride: 6.4 parts by mass (0.03 mol; 20.0 mol% based on the total number of polycarboxylic acids)
Thereafter, the above materials are added, the pressure in the reaction vessel is lowered to 8.3 kPa, and the reaction is performed for 15 hours while maintaining the temperature at 160 ° C. (second reaction step), and polyester resin B6 having a weight average molecular weight (Mw) of 100,000. Got.

<Amorphous polyester resin B production example 7>
In a reaction vessel equipped with a condenser, a stirrer, and a nitrogen introduction pipe, 130 parts by mass of propylene glycol, 283 parts by mass of terephthalic acid, 22 parts by mass of trimellitic anhydride and 2 parts by mass of dibutyltin oxide were placed at 230 ° C. for 8 hours. The mixture was further reacted and reacted at 10 to 15 mmHg for 5 hours to obtain a second amorphous polyester B7. Amorphous polyester B7 had a glass transition point of 62 ° C. and a weight average molecular weight of 23,000.

<Crystalline polyester resin C production example 1>
-1,10-decanediol: 46.9 parts by mass (0.27 mol; 100.0 mol% based on the total number of moles of polyhydric alcohol)
-Sebacic acid: 53.1 parts by mass (0.26 mol; 100.0 mol% based on the total number of polyvalent carboxylic acids)
The above materials were weighed into a reaction vessel equipped with a cooling tube, a stirrer, a nitrogen introduction tube, and a thermocouple. Next, after the inside of the flask was replaced with nitrogen gas, the temperature was gradually raised while stirring, and the reaction was carried out for 3 hours while stirring at a temperature of 140 ° C.

-Tin 2-ethylhexanoate: 0.5 part by mass Thereafter, the above materials were added, the pressure in the reaction vessel was lowered to 8.3 kPa, and the reaction was continued for 4 hours while maintaining the temperature at 200 ° C. Got.

<Production Example 2 of Crystalline Polyester Resin C>
A crystalline polyester resin C2 was obtained in the same manner as in Production Example 1 of the crystalline polyester resin C except that 1,10-decanediol was changed to 1,6-hexanediol and sebacic acid was changed to fumaric acid.

<Crystalline polyester resin C production example 3>
In a 5 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, 2,120 parts by mass of 1,10-decanedicarboxylic acid, 1,520 parts by mass of 1,6-hexanediol, and 3.9 parts by mass of hydroquinone The mixture was reacted at 180 ° C. for 10 hours, heated to 200 ° C. and reacted for 3 hours, and further reacted at 8.3 kPa for 2 hours to obtain crystalline polyester C3. Crystalline polyester C3 had a melting point of 67 ° C. and a weight average molecular weight of 1.5 × 10 ⁴ .

<Toner Production Example 1>
Polyester resin A1 70 parts by mass Polyester resin B1 30 parts by mass Polyester resin C1 10 parts by mass Hydrocarbon wax (peak temperature of maximum endothermic peak 78 ° C.) 2 parts by mass I. Pigment Blue 15: 3 5 parts by mass, 3,5-di-t-butylsalicylic acid aluminum compound 0.5 part by mass Using the above materials with a Henschel mixer (FM-75 type, manufactured by Mitsui Mining Co., Ltd.), the number of revolutions After mixing for 20 s ⁻¹ and a rotation time of 5 minutes, the mixture was kneaded at a discharge temperature of 150 ° C. with a twin-screw kneader (PCM-30 type, manufactured by Ikegai Co., Ltd.) set at a temperature of 130 ° C. The obtained kneaded product was cooled at a cooling rate of 15 ° C./min, and coarsely pulverized to 1 mm or less with a hammer mill to obtain a coarsely pulverized product. The obtained coarsely crushed material was finely pulverized with a mechanical pulverizer (T-250, manufactured by Turbo Kogyo Co., Ltd.). Further, classification was performed using Faculty F-300 (manufactured by Hosokawa Micron Corporation) to obtain toner particles. The operating conditions were a classification rotor rotational speed of 130 s ⁻¹ and a distributed rotor rotational speed of 120 s ⁻¹ .

To 100 parts by mass of the obtained toner particles, 1.0 part by mass of hydrophobic silica fine particles having a BET specific surface area of 25 m ² / g surface-treated with 4% by mass of hexamethyldisilazane and BET surface-treated with 10% by mass of polydimethylsiloxane. 0.8 parts by mass of hydrophobic silica fine particles having a specific surface area of 100 m ² / g were added and mixed with a Henschel mixer (FM-75 type, manufactured by Mitsui Miike Chemical Co., Ltd.) at a rotation speed of 30 s ⁻¹ and a rotation time of 10 minutes. Toner 1 was obtained. The weight average particle diameter (D4) of Toner 1 was 6.1 μm.

<Toner Production Examples 2 to 19, 21 to 23>
Toners 2 to 19, and 21 to 23 were produced in the same manner as in Toner Production Example 1 except that the amounts and types of Resin A, Resin B, and Resin C, kneading temperature, and cooling rate after kneading were varied. Table 1 shows the material formulation and manufacturing conditions.

<Toner Production Example 20>
In an autoclave reaction vessel equipped with a thermometer and a stirrer, 70 parts by mass of low molecular weight polyethylene sun wax 151P (manufactured by Sanyo Chemical Industries) having a melting point of 108 ° C. and 480 parts by mass of xylene were added, and the temperature was raised to 170 ° C. Replaced with nitrogen. Next, a solution prepared by dissolving 805 parts by mass of styrene, 50 parts by mass of acrylonitrile, 45 parts by mass of butyl acrylate, and 36 parts by mass of di-t-butyl peroxide in 100 parts of xylene was dropped in 3 hours, and the temperature was 30 ° C. at 170 ° C. After holding for a minute, the solvent was removed to obtain Dispersant 1. Dispersant 1 had a weight average molecular weight of 1.8 × 10 ⁴ .

  6 parts of crystalline polyester C2, 73 parts by weight of amorphous polyester A6, 16 parts by weight of amorphous polyester B7, 1.6 parts by weight of dispersant 1 for crystalline polyester, average particle size of 24 nm, C.I. I. 5 parts by weight of Pigment Blue 15: 3, 1 part by weight of Bontron E-84 (manufactured by Orient Chemical Co., Ltd.) and 2 parts by weight of paraffin wax HNP-9 (manufactured by Nippon Seiki Co., Ltd.) having a melting point of 75 ° C. -200 (manufactured by Kawata) was mixed to obtain a mixture. The obtained mixture was supplied to a raw material supply hopper of Busco Kneader TCS-100 (manufactured by Buss), and kneaded at a discharge temperature of 120 ° C. with a supply amount of 120 kg / h to obtain a kneaded product. The obtained kneaded material was rolled and cooled using a double belt cooler at a cooling rate of 30 ° C./min, then coarsely pulverized using a hammer mill, and a jet airflow pulverizer I-20 jet mill (Nippon Pneumatic) And finely pulverized. Next, classification is performed using a wind classifier DS-20 / DS-10 classifier (manufactured by Nippon Pneumatic Co., Ltd.), fine particles are removed, and then left at 50 ° C. for 24 hours, followed by annealing to obtain base particles. It was.

  Using a Henschel mixer, 100 parts by mass of base particles, 0.7 parts by mass of hydrophobic silica, and 0.3 parts by mass of hydrophobic titanium oxide were mixed to obtain toner 20.

  Table 2 shows various analysis results of the obtained toner.

<Example of production of magnetic core particles>
Process 1 (weighing / mixing process):
Fe ₂ O ₃ 60.2 mass%
MnCO ₃ 33.9% by mass
Mg (OH) ₂ 4.8% by mass
SrCO ₃ 1.1% by mass
The ferrite raw material was weighed so that Thereafter, the mixture was pulverized and mixed for 2 hours in a dry ball mill using zirconia (φ10 mm) balls.

Step 2 (temporary firing step):
After pulverization and mixing, firing was performed at 1000 ° C. for 3 hours in the air using a burner-type firing furnace to prepare calcined ferrite. The composition of ferrite is as follows.
(MnO) a (MgO) b (SrO) c (Fe 2 O 3) d
In the above formula, a = 0.39, b = 0.11, c = 0.01, d = 0.50

Step 3 (grinding step):
After crushing to about 0.5 mm with a crusher, 30 parts by mass of water was added to 100 parts by mass of calcined ferrite using zirconia (φ10 mm) balls, and the mixture was pulverized with a wet ball mill for 2 hours.

  The slurry was pulverized for 4 hours by a wet bead mill using zirconia beads (φ1.0 mm) to obtain a ferrite slurry.

Process 4 (granulation process):
To the ferrite slurry, 2.0 parts by mass of polyvinyl alcohol was added as a binder with respect to 100 parts by mass of calcined ferrite, and granulated into spherical particles of about 36 μm with a spray dryer (manufacturer: Okawahara Chemical).

Process 5 (main baking process):
In order to control the firing atmosphere, firing was performed at 1150 ° C. for 4 hours in an electric furnace under a nitrogen atmosphere (oxygen concentration of 1.00% by volume or less).

Process 6 (screening process):
After the aggregated particles were crushed, coarse particles were removed by sieving with a sieve having an opening of 250 μm to obtain magnetic core particles 1.

<Example of coating resin production>
Cyclohexyl methacrylate monomer 26.8 parts by mass Methyl methacrylate monomer 0.2 part by mass Methyl methacrylate macromonomer 8.4 parts by mass (macromonomer having a methacryloyl group at one end and a weight average molecular weight of 5000)
Toluene 31.3 parts by mass Methyl ethyl ketone 31.3 parts by mass The above materials were added to a four-necked separable flask equipped with a reflux condenser, thermometer, nitrogen introduction tube and stirring device, and nitrogen gas was introduced to sufficiently In a nitrogen atmosphere. Thereafter, the mixture was heated to 80 ° C., 2.0 parts by mass of azobisisobutyronitrile was added, and the mixture was refluxed for 5 hours for polymerization. Hexane was injected into the obtained reaction product to precipitate a copolymer, and the precipitate was filtered off and dried under vacuum to obtain a coat resin.

<Example of magnetic carrier production>
Coat resin 20.0% by mass
Toluene 80.0% by mass
The above materials were dispersed and mixed with a bead mill to obtain a resin liquid.

  100 parts by mass of the magnetic core particles were put into a Nauta mixer, and further, the resin liquid was put into a Nauta mixer so as to be 2.0 parts by mass as a resin component. The mixture was heated to 70 ° C. under reduced pressure, mixed at 100 rpm, and solvent removal and coating operations were performed over 4 hours. Thereafter, the obtained sample was transferred to a Julia mixer, heat-treated at 100 ° C. for 2 hours in a nitrogen atmosphere, and then classified with a sieve having an opening of 70 μm to obtain a magnetic carrier. The volume distribution standard 50% particle size (D50) of the obtained magnetic carrier was 38.2 μm.

[Examples 1 to 17, Comparative Examples 1 to 6]
In more toner 1 to 23 and magnetic carrier, a toner concentration of 8.0% by mass so as to V-type mixer: with (V-10 type, Ltd. Tokuju Seisakusho) 0.5 s ^-1, at rotation time 5min By mixing, two-component developers 1 to 23 were obtained.

<Developability evaluation>
Canon full-color copier imageRUNNER ADVANCE C9075PRO as an image forming apparatus was remodeled so that the process speed could be freely set, and two-component developers 1 to 23 were used for evaluation.

  Image evaluation (A4 landscape, 80% printing rate, continuous 5,000 sheets) was performed under the conditions of changing the process speed to 450 mm / sec in a normal temperature and humidity environment (23 ° C., 50% RH).

During the 5,000 continuous sheet passing time, the sheet is passed under the same development conditions and transfer conditions (no calibration) as the first sheet. The evaluation paper used was copy paper GF-C081 (A4, basis weight 81.4 g / m ² ) sold by Canon Marketing Japan Inc. In the evaluation environment, the amount of the FFH image (solid portion) applied on the paper was adjusted to 0.50 mg / cm ² . The FFH image is a value in which 256 gradations are displayed in hexadecimal, and 00H is the first gradation (white background), and FFH is the 256th gradation (solid part).

  The items and evaluation criteria for image output evaluation at the initial stage (first sheet) and when 5,000 sheets are continuously fed are shown below.

(Initial (first image) and 5,000 consecutive image density measurements)
An X-Rite color reflection densitometer (500 series: manufactured by X-Rite) was used to measure the image density (FFH image portion; solid portion).

  The difference in image density between the initial (first sheet) and the 5,000th FFH image area; the solid area was evaluated according to the following criteria.

(Evaluation criteria)
A: Less than 0.05 (very good)
B: 0.05 or more and less than 0.10 (Excellent)
C: 0.10 or more (prior art level)

<Evaluation of charging rise>
1.0 g of toner and 9.0 g of carrier were put in a 50 cc plastic bottle and shaken with a Yayoi shaker at 200 rpm to evaluate the rise of charging property. The toner charge amount at a shaking time of 30, 60, 120, 180, 300, 600, and 1200 seconds was measured by an average charge amount (μC / g) using an E-Spart Analyzer manufactured by Hosokawa Micron. The time constant τ was calculated by fitting the following equation to the obtained measurement result.

(Evaluation criteria)
A: Less than 100 sec (very good)
B: 100 sec or more and less than 150 sec (excellent)
C: 150 sec or more (prior art level)

<Evaluation of fixability (hot offset resistance, low temperature fixability)>
A two-component developer that was allowed to stand in a temperature and humidity environment of 35 ° C. and 90% Rh for 1 week was used.

A Canon full-color copier imageRUNNER ADVANCE C9075PRO was modified so that the fixing temperature and process speed could be freely set, and the fixing temperature region test was conducted. The image was adjusted so that the amount of toner applied on the paper was 0.8 mg / cm ² in a single color mode in a normal temperature and normal humidity environment (23 ° C./50% Rh), and an unfixed image was created. The evaluation paper used was copy paper GF-C081 (A4, basis weight 81.4 g / m ² , sold by Canon Marketing Japan Inc.), and an image was formed at an image printing ratio of 25%. Thereafter, in a high-temperature and low-humidity environment (30 ° C./15% Rh), the process speed is set to 100 mm / sec, and the fixing temperature is increased by 5 ° C. in order from 100 ° C. The offset generation temperature was defined as the fixable region, the lower limit temperature was the low temperature fixing temperature, and the upper limit temperature was the hot offset temperature.

(Evaluation criteria: Hot offset resistance)
A: 240 ° C. or higher (excellently excellent)
B: 230 ° C. or higher and lower than 240 ° C. (very good)
C: 220 ° C. or higher and lower than 230 ° C. (excellent)
D: 205 ° C. or higher and lower than 220 ° C. (A little better)
E: 170 ° C or higher and lower than 205 ° C (prior art level)
F: less than 170 ° C.

(Evaluation criteria: low temperature fixability)
A: Less than 125 ° C (excellently excellent)
B: 125 ° C. or higher and lower than 135 ° C. (very good)
C: 135 ° C or higher and lower than 145 ° C (excellent)
D: 145 ° C or higher and lower than 155 ° C (slightly better)
E: 155 ° C or higher and lower than 175 ° C (prior art level)
F: 175 ° C or higher (inferior to conventional)

<Evaluation of storage stability (high temperature)>
10 g of toner was placed in a 100 cc polycup and left in a temperature and humidity variable temperature thermostat for 48 hours, and the temperature at which the toner aggregated after being left was evaluated. When the powder tester PT-X manufactured by Hosokawa Micron Co., Ltd. was shaken with a mesh having a mesh size of 250 μm for 60 seconds with an amplitude of 1.0 mm, it was defined as aggregated NG.

  The high temperature storage stability was increased from 40 ° C. to 2.5 ° C. in increments of 10% Rh or less.

(Evaluation criteria: high temperature)
A: 60 ° C or higher (excellent)
B: 55 ° C. or higher and lower than 60 ° C. (A little better)
C: 45 ° C or higher and lower than 55 ° C (prior art level)
D: Less than 45 ° C (inferior to conventional)

  Table 3 shows the results of evaluating the toner by the above evaluation methods and standards.

  As shown by the above results, the presence of crystalline polyester crystals in the toner cross section contains a large number of crystal domains that are observed as needles having a major axis length of 100 nm to 250 nm, and the hot offset resistance is remarkable. An improved toner can be obtained.

Claims (8)

A toner containing an amorphous polyester resin and a crystalline polyester,
In the endothermic curve at the time of temperature rise measured by the differential scanning calorimeter (DSC) of the toner, the endothermic amount ΔH derived from the crystalline polyester is 1.0 J / g or more and 5.0 J / g or less,
In the cross section of the toner observed by a transmission electron microscope (TEM), crystals of the crystalline polyester observed in a needle shape are dispersed, and in the number distribution of the major axis length of the crystals, the major axis length The toner has a crystal cross-section of at least 100 nm and at most 250 nm in an amount of 30% by number or more.   The toner according to claim 1, wherein in the number distribution of the major axis length of the crystal, the major axis has a number peak between 60 nm and 250 nm.   3. The toner according to claim 1, wherein 90% by number or more of acicular crystals having a minor axis length of 5 nm to 15 nm are present in a number distribution of minor axis lengths of the crystals.   The toner according to claim 1, wherein the content of the polyester resin in the toner is 70% by mass or more.   The toner according to any one of claims 1 to 4, wherein the alcohol component of the amorphous resin is an alkylene oxide adduct having 2 to 4 carbon atoms of bisphenols.   The amorphous polyester resin contains a resin A and a resin B having different weight average molecular weights, and the resin B has a weight average molecular weight higher than that of the resin A, and the resin A and the resin B are The toner according to any one of claims 1 to 5, wherein a ratio of the resin B is 20% by mass to 40% by mass.   The amorphous resin has a polyhydric alcohol unit and a polycarboxylic acid unit, and the polyhydric alcohol unit contains a polyhydric alcohol unit derived from an oxyalkylene ether of a novolak-type phenol resin. The toner according to claim 1.   8. A release agent is included, and the total DSC endothermic amount [Delta] H of the release agent and the crystalline polyester is 4.0 J / g or more and 7.0 J / g or less. The toner described in 1.

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