JP5870596B2 - Toner, developer and image forming method - Google Patents

Description

  The present invention relates to a toner, a developer, and an image forming method.

  In an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus, a toner image formed by developing an electrostatic latent image formed on a photoreceptor using toner is applied to a recording medium such as paper. After the transfer, the image is formed by fixing by heating. In forming a full-color image, development is generally performed using toners of four colors, black, yellow, magenta, and cyan. The toner images of the respective colors are transferred onto a recording medium and superimposed, and then heated. Fix at the same time.

  At this time, if the low-temperature fixability of the toner is improved, there is a problem that the heat-resistant storage stability of the toner is lowered.

  Therefore, Patent Document 1 discloses a core-shell type toner containing a release agent, a colorant, a binder resin and a filler as an electrostatic charge image developing toner. At this time, the flow tester 1/2 outflow temperature of the toner is 60 ° C. or higher and 100 ° C. or lower, and the shell contains the thermoplastic resin.

  However, there is a problem that low-temperature fixability, spent resistance, and hot offset resistance cannot be achieved in a high-temperature and high-humidity environment.

  The present invention has been made in view of the above-described problems of the prior art, a toner excellent in low-temperature fixability, spent resistance and hot offset resistance in a high-temperature and high-humidity environment, a developer having the toner and carrier, and an image using the developer. An object is to provide a forming method.

  The toner of the present invention has base particles having a core-shell structure composed of a core containing crystalline polyester, amorphous polyester, a colorant and a release agent, and a shell containing resin, and has a thermal hardness of 0.5. The softening index is 80 ° C. or higher and 95 ° C. or lower, and the thermal retention is 30 ° C. or higher and 50 ° C. or lower.

  The developer of the present invention has the toner and carrier of the present invention.

The image forming method of the present invention is a method of forming a full-color image using a tandem image forming apparatus, the step of forming electrostatic latent images on a plurality of electrostatic latent image carriers, and the plurality of static images. The step of developing the electrostatic latent image formed on the electrostatic latent image carrier using the developer of the present invention to form a toner image, and the toner images formed on the plurality of electrostatic latent image carriers. A step of sequentially transferring to the intermediate transfer member to form a full color toner image, a step of transferring the full color toner image transferred to the intermediate transfer member to a recording medium, and a full color toner image transferred to the recording medium to 1 It has a step of fixing by heating with a surface pressure of × 10 ⁵ Pa or more and 3 × 10 ⁷ Pa or less for 0.03 seconds or more and 0.4 seconds or less, and the system speed is 0.2 m / s or more and 3 m / second. s or less.

  According to the present invention, it is possible to provide a toner excellent in low-temperature fixability, spent resistance and hot offset resistance in a high-temperature and high-humidity environment, a developer having the toner and a carrier, and an image forming method using the developer. it can.

It is a figure explaining the thermal hardness of a toner. It is a figure explaining the softening index | exponent of a toner. FIG. 6 is a diagram for explaining thermal retention of toner. It is a figure explaining the measuring method of the thermal hardness of a toner, a softening index | exponent, and thermal retention. It is a figure which shows an example of the image forming apparatus used by this invention. It is a figure which shows the image forming unit of FIG.

  Next, the form for implementing this invention is demonstrated with drawing.

  The toner of the present invention has base particles having a core-shell structure including a core containing crystalline polyester, amorphous polyester, colorant and release agent, and a shell containing resin.

  Conventionally, low-temperature fixability, spent resistance and hot offset resistance in a high-temperature and high-humidity environment are in a trade-off relationship, and it has been difficult to achieve both.

  Therefore, in the present invention, the core and the shell are function-separated types each having a unique function, and the functions of the core and the shell are highly balanced, so that the low-temperature fixability, the spent resistance in a high-temperature and high-humidity environment, It has become possible to achieve both hot offset resistance.

  Specifically, the thermal hardness St is defined as a parameter for controlling the function of the shell so as to withstand development stress and prevent the components contained in the core from being exposed on the surface of the toner. The thermal hardness St reflects the thickness of the shell, the characteristics of the resin contained in the shell, and the like.

  Further, a softening index Ct is defined as a parameter for controlling the function of the core so that components contained in the core are not exposed on the surface of the toner. The softening index Ct reflects the characteristics of the crystalline polyester contained in the core.

  Furthermore, the thermal retention Ht is defined as a parameter for controlling the temperature difference from when the core starts to melt until it completely melts. The thermal retention Ht reflects the characteristics of the amorphous polyester contained in the core.

  The thermal hardness St of the toner of the present invention is 0.5 to 1.8, preferably 1.0 to 1.7. When the thermal hardness St is less than 0.5, the spent resistance of the toner in a high temperature and high humidity environment decreases, and when it exceeds 1.8, the low temperature fixability of the toner in a high temperature and high humidity environment decreases. .

  The thermal hardness St is measured by using a flow tester CFT-500D (manufactured by Shimadzu Corporation) to measure the toner outflow start temperature when the load is 2 to 25 kgf. It is the product of the slope when the outflow start temperature is plotted and −1 (see FIG. 1). That is, the thermal hardness St indicates the load dependency of the ease of melting of the toner. At this time, if the load is 25 kgf, it is considered that the structure of the shell is destroyed. Therefore, when the thermal hardness St is small, the outflow start temperature does not increase even if the load is reduced. That is, even if the load is small, the structure of the shell is destroyed, so that the toner is easily melted. On the other hand, when the thermal hardness St is large, when the load is reduced, the toner outflow start temperature increases. That is, when the load is small, the structure of the shell is difficult to be destroyed, so that the toner is difficult to melt.

  The toner of the present invention has a softening index Ct of 80 to 95 ° C, preferably 86 to 90 ° C. When the softening index Ct is less than 80 ° C., the spent resistance of the toner in a high temperature and high humidity environment decreases, and when it exceeds 95 ° C., the low temperature fixability of the toner in a high temperature and high humidity environment decreases.

  The softening index Ct is a toner outflow start temperature when the load is 25 kgf, measured using a flow tester CFT-500D (manufactured by Shimadzu Corporation) (see FIG. 2). At this time, if the load is 25 kgf, it is considered that the shell structure is broken. Therefore, the softening index Ct indicates the ease of melting of the toner whose core structure is broken, that is, the core.

  The thermal retention Ht of the toner of the present invention is 30 to 50 ° C., preferably 35 to 45 ° C. When the thermal retention Ht is less than 30 ° C., the hot offset resistance of the toner in a high-temperature and high-humidity environment decreases, and when it exceeds 50 ° C., the low-temperature fixability of the toner in a high-temperature and high-humidity environment decreases.

  The thermal retention Ht is the difference between the toner outflow end temperature and the outflow start temperature when the load is 25 kgf, measured using a flow tester CFT-500D (manufactured by Shimadzu Corporation) (FIG. 3). reference). At this time, if the load is 25 kgf, it is considered that the structure of the shell is destroyed. Therefore, the thermal retention Ht indicates a margin for the toner whose structure of the shell is broken, that is, the hot offset of the core. .

The flow tester CFT-500D (manufactured by Shimadzu Corporation) put toner T, which was compressed into a cylindrical shape and tableted, into a cylinder C and preheated to T _s [° C.] as shown in FIG. Thereafter, by heating the heating element H while applying a constant load by the plunger P, the molten toner T ′ flows out from the die D, and as shown in FIG. Measure the amount of plunger P descending with respect to the temperature. The flow tester CFT-500D (manufactured by Shimadzu Corporation) is generally used when measuring the outflow start temperature T _fb or T _1/2 temperature with a constant load, but in the present invention, the load is changed. By measuring the outflow start temperature T _fb and the outflow end temperature T _end , the thermal hardness St, the softening index Ct, and the thermal retention Ht can be evaluated.

  The thickness of the shell is preferably 0.01 to 2 μm, and more preferably 0.4 to 1.5 μm. If the shell thickness is less than 0.01 μm, the spent resistance of the toner in a high-temperature and high-humidity environment may be reduced. If the thickness exceeds 2 μm, the low-temperature fixability of the toner in a high-temperature and high-humidity environment will be reduced. Sometimes.

  The thickness of the shell can be measured using a transmission electron microscope, and is an average value of the thicknesses of the shells of ten toners measured at random.

The crystalline polyester heats polyvalent carboxylic acid and polyhydric alcohol to 180-230 ° C. in the presence of a catalyst, and distills off water and alcohol produced while reducing pressure, if necessary.
It can be synthesized by condensation.

  The catalyst is not particularly limited, but sodium acetate, sodium carbonate, lithium acetate, lithium carbonate, calcium acetate, calcium stearate, magnesium acetate, zinc acetate, zinc stearate, zinc naphthenate, zinc chloride, manganese acetate, manganese naphthenate , Titanium tetraethoxide, titanium tetrapropoxide, titanium tetraisopropoxide, titanium tetrabutoxide, antimony trioxide, triphenylantimony, tributylantimony, tin formate, tin oxalate, tetraphenyltin, dibutyltin dichloride, dibutyltin oxide, diphenyltin Oxide, zirconium tetrabutoxide, zirconium naphthenate, zirconyl carbonate, zirconyl acetate, zirconyl stearate, zirconyl octylate, acid Germanium, triphenyl phosphite, tris (2,4-di -t- butyl-phenyl) phosphite, ethyltriphenylphosphonium bromide, triethylamine, triphenylamine, and the like.

  The polyvalent carboxylic acid is not particularly limited, but oxalic acid, succinic acid, glutaric acid, adipic acid, peric acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1 , 12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid and other aliphatic dicarboxylic acids; phthalic acid, isophthalic acid, terephthalic acid, naphthalene-2,6-dicarboxylic acid, malonic acid, Aromatic dicarboxylic acids such as mesaconic acid, aromatic tricarboxylic acids such as 1,2,4-benzenetricarboxylic acid, 1,2,5-benzenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, etc. Two or more species may be used in combination.

  In place of the polyvalent carboxylic acid, an anhydride of the polyvalent carboxylic acid or a lower alkyl ester of the polyvalent carboxylic acid may be used.

  Moreover, the polyvalent carboxylic acid may contain a dicarboxylic acid having a sulfonic acid group, or may contain a dicarboxylic acid having a double bond.

  The polyhydric alcohol is usually an aliphatic alcohol, preferably a linear aliphatic diol having 7 to 20 carbon atoms in the main chain, and a linear alcohol having 7 to 14 carbon atoms in the main chain. Aliphatic diols are more preferred. If the aliphatic diol is branched, the crystallinity of the crystalline polyester may be lowered, and the melting point may be lowered. If the main chain has less than 7 carbon atoms, condensation with an aromatic dicarboxylic acid may increase the melting point and lower the low-temperature fixability of the toner. On the other hand, when the number of carbons in the main chain exceeds 20, it becomes difficult to obtain.

  Examples of the aliphatic diol include, but are not limited to, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1 , 8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, , 18-octadecanediol, 1,14-eicosandecanediol, etc., may be used in combination. Among these, 1,8-octanediol, 1,9-nonanediol or 1,10-decanediol is preferable because it is easily available.

  Although it does not specifically limit as aliphatic alcohol more than trivalence, Glycerin, a trimethylol ethane, a trimethylol propane, a pentaerythritol etc. are mentioned, You may use 2 or more types together.

  The content of the aliphatic diol in the polyhydric alcohol is usually 80 to 100 mol%, preferably 90 to 100 mol%. When the content of the aliphatic diol in the polyhydric alcohol is less than 80 mol%, the crystallinity of the crystalline polyester is lowered and the melting point is lowered, so that the heat resistant storage stability, image storage stability and low temperature fixability of the toner are improved. May decrease.

  In addition, when synthesizing the crystalline polyester, a polyvalent carboxylic acid or a polyhydric alcohol may be added at the final stage of the synthesis in order to adjust the acid value or the hydroxyl value, if necessary.

  Although it does not specifically limit as polyhydric carboxylic acid, Aromatic carboxylic acids, such as terephthalic acid, isophthalic acid, phthalic anhydride, trimellitic anhydride, pyromellitic acid, naphthalenedicarboxylic acid; maleic anhydride, fumaric acid, succinic acid And aliphatic carboxylic acids such as alkenyl succinic anhydride and adipic acid; and alicyclic carboxylic acids such as cyclohexanedicarboxylic acid.

  Although it does not specifically limit as polyhydric alcohol, Aliphatic diols, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentylglycol, glycerin; cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol And alicyclic diols such as A; aromatic diols such as bisphenol A ethylene oxide adduct and bisphenol A propylene oxide adduct.

  In addition, when the polycarboxylic acid and the polyhydric alcohol are not dissolved or compatible, they may be dissolved by adding a solvent, or the polycarboxylic acid (or polyhydric alcohol) and the polyhydric alcohol (which have low compatibility in advance) Or a polyvalent carboxylic acid) may be condensed and then condensed with a highly compatible polyvalent carboxylic acid (or polyhydric alcohol).

  The melting point of the crystalline polyester is usually 50 to 100 ° C, preferably 55 to 90 ° C, and more preferably 60 to 85 ° C. If the melting point of the crystalline polyester is less than 50 ° C., the heat-resistant storage stability of the toner may be lowered, and if it exceeds 100 ° C., the low-temperature fixability of the toner may be lowered.

  In the present invention, the melting point can be measured using DSC.

  The acid value of the crystalline polyester is usually 3 to 30 mgKOH / g, preferably 6 to 25 mgKOH / g, and more preferably 8 to 20 mgKOH / g. If the acid value of the crystalline polyester is less than 3 mgKOH / g, the stability of the base particles may be reduced, making it difficult to produce the toner efficiently. If the acid value exceeds 30 mgKOH / g, Increases hygroscopicity and may be susceptible to environmental influences.

  In the present invention, the acid value can be measured according to the measurement method described in JIS K0070-1992.

The weight average molecular weight of the crystalline polyester is usually 6 × 10 ^{3 to} 3.5 × 10 ⁴ . When the weight average molecular weight of the crystalline polyester is less than 6 × 10 ³ , when fixing the toner image transferred to the recording medium, the toner penetrates into the surface of the recording medium, and fixing unevenness occurs. The strength against bending may decrease, and if it exceeds 3.5 × 10 ⁴ , the low-temperature fixability of the toner may decrease.

  In the present invention, the weight average molecular weight can be measured using GPC, and is a molecular weight in terms of polystyrene.

  The content of the crystalline polyester in the toner is usually 3 to 40% by mass, preferably 4 to 35% by mass, and more preferably 5 to 30% by mass. If the content of the crystalline polyester in the toner is less than 3% by mass, the low-temperature fixability of the toner may be reduced. If it exceeds 40% by mass, the strength of the toner and the strength of the fixed image may be reduced. The chargeability of the toner may be reduced.

  Amorphous polyester is prepared by heating polyol and polycarboxylic acid to 150-280 ° C in the presence of a catalyst such as tetrabutoxy titanate or dibutyltin oxide, and distilling off the water and alcohol produced while reducing the pressure as necessary. And can be synthesized by condensation.

  Examples of the polyol include a diol and a trihydric or higher polyol, and a combination of a diol or a diol and a trihydric or higher polyol is preferable.

  The diol is not particularly limited, but alkylene glycol such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,6-hexanediol; diethylene glycol, triethylene glycol, Alkylene ether glycols such as dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol; alicyclic diols such as 1,4-cyclohexanedimethanol and hydrogenated bisphenol A; bisphenol A, bisphenol F, bisphenol S, etc. Bisphenols; Aliphatic diols or alkylene oxide adducts of bisphenols such as ethylene oxide, propylene oxide, butylene oxide, etc. Gerare, it may be used in combination of two or more. Among them, alkylene glycols having 2 to 12 carbon atoms and alkylene oxide adducts of bisphenols are preferable, and the combination of alkylene oxide adducts of bisphenols and alkylene oxide adducts of bisphenols with alkylene glycols having 2 to 12 carbon atoms is preferable. Particularly preferred.

  Examples of the trihydric or higher polyol include 3 to 8 or more polyhydric aliphatic alcohols such as glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and sorbitol; 3 such as trisphenol PA, phenol novolak, and cresol novolak. More than trivalent phenols; for example, alkylene oxide adducts such as ethylene oxide, propylene oxide, butylene oxide of trivalent or more phenols, etc. may be used in combination.

  Examples of the polycarboxylic acid include dicarboxylic acids and trivalent or higher polycarboxylic acids, and dicarboxylic acids or combinations of dicarboxylic acids and trivalent or higher polycarboxylic acids are preferable.

  The dicarboxylic acid is not particularly limited, but alkylene dicarboxylic acids such as succinic acid, adipic acid and sebacic acid; alkenylene dicarboxylic acids such as maleic acid and fumaric acid; aromatics such as phthalic acid, isophthalic acid, terephthalic acid and naphthalenedicarboxylic acid Group dicarboxylic acid and the like, and two or more of them may be used in combination. Among these, alkenylene dicarboxylic acids having 4 to 20 carbon atoms and aromatic dicarboxylic acids having 8 to 20 carbon atoms are preferable.

  Examples of the trivalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms such as trimellitic acid and pyromellitic acid, and two or more kinds may be used in combination.

  In place of polycarboxylic acid, polycarboxylic acid anhydride or lower alkyl ester such as methyl ester, ethyl ester, isopropyl ester may be used.

The peak molecular weight of the amorphous polyester is usually 1 × 10 ^{3 to} 3 × 10 ⁴ , preferably 1.5 × 10 ³ to 1 × 10 ^{4, and} more preferably 2 × 10 ³ to 8 × 10 ³ . When the peak molecular weight of the amorphous polyester is less than 1 × 10 ³ , the heat-resistant storage stability of the toner may be lowered, and when it exceeds 3 × 10 ⁴ , the low-temperature fixability of the toner may be lowered.

  In the present invention, the peak molecular weight can be measured using GPC, and is a molecular weight in terms of polystyrene.

  The hydroxyl value of the amorphous polyester is usually 5 mgKOH / g or more, preferably 10 to 120 mgKOH / g, more preferably 20 to 80 mgKOH / g. If the hydroxyl value of the amorphous polyester is less than 5 mgKOH / g, the hot offset resistance of the toner may be lowered, and it may be difficult to achieve both heat resistant storage stability and low temperature fixability.

  In this invention, a hydroxyl value can be measured based on the measuring method as described in JISK1557-1.

  The acid value of the amorphous polyester is usually 0.5 to 40 mgKOH / g, preferably 5 to 35 mgKOH / g. When the acid value is less than 0.5 mgKOH / g, it may be difficult to make the toner negatively charged. When the acid value exceeds 40 mgKOH / g, the influence of the environment under high temperature and high humidity and low temperature and low humidity. The image is likely to be deteriorated.

  The core preferably further contains urea-modified polyester. Thereby, the low temperature fixability and the glossiness and gloss uniformity of a full color image can be improved.

  The urea-modified polyester can be synthesized by adding a polyester prepolymer having an isocyanate group and a compound having an amino group in the presence of a catalyst such as dibutyltin laurate or dioctyltin laurate. At this time, reaction time is 10 minutes-40 hours normally, and 2-24 hours are preferable. Moreover, reaction temperature is 0-150 degreeC normally, and 40-98 degreeC is preferable.

  The polyester prepolymer having an isocyanate group can be synthesized by adding a polyester having an active hydrogen group and a polyisocyanate at 40 to 140 ° C. Examples of the active hydrogen group include a hydroxyl group (alcoholic hydroxyl group and phenolic hydroxyl group), an amino group, a carboxyl group, a mercapto group, etc. Among them, an alcoholic hydroxyl group is preferable.

  A polyester having an alcoholic hydroxyl group as an active hydrogen group can be synthesized by condensing the aforementioned polyol and polycarboxylic acid. At this time, the molar ratio of the alcoholic hydroxyl group to the carboxyl group is usually 1 to 2, preferably 1 to 1.5, and more preferably 1.02 to 1.3.

  Although it does not specifically limit as polyisocyanate, Aliphatic polyisocyanate, such as tetramethylene diisocyanate, hexamethylene diisocyanate, 2, 6- diisocyanato methyl caproate; Cycloaliphatic polyisocyanate, such as isophorone diisocyanate, cyclohexyl methane diisocyanate; Examples thereof include aromatic diisocyanates such as diisocyanate and diphenylmethane diisocyanate; araliphatic diisocyanates such as α, α, α ′, α′-tetramethylxylylene diisocyanate; isocyanurates and the like.

  In place of polyisocyanate, polyisocyanate blocked with a phenol derivative, oxime, caprolactam or the like may be used.

  The molar ratio of the isocyanate group to the alcoholic hydroxyl group when adding the polyester having an active hydrogen group and the polyisocyanate is usually 1 to 5, preferably 1.2 to 4, and more preferably 1.5 to 2.5. preferable. If this molar ratio is less than 1, the content of urea bonds in the urea-modified polyester is reduced, and the hot offset resistance of the toner may be reduced. If it exceeds 5, the low-temperature fixability of the toner is reduced. There are things to do.

  The content of the component derived from polyisocyanate in the polyester prepolymer having an isocyanate group is usually 0.5 to 40% by mass, preferably 1 to 30% by mass, and more preferably 2 to 20% by mass. When this content is less than 0.5% by mass, the hot offset resistance of the toner may be lowered, and when it exceeds 40% by mass, the low-temperature fixability of the toner may be lowered.

  The average value of the isocyanate group content per molecule of the polyester prepolymer having an isocyanate group is usually 1 or more, preferably 1.5 to 3, more preferably 1.8 to 2.5. . If the average value of the contents is less than 1, the molecular weight of the urea-modified polyester becomes small, and the hot offset resistance of the toner may be lowered.

  Although it does not specifically limit as a compound which has an amino group, Although a diamine, a trivalent or more polyamine, an amino alcohol, an amino mercaptan, an amino acid, etc. are mentioned, Combination use of a diamine or a diamine and a trivalent or more polyamine is preferable.

  Examples of the diamine include aromatic diamines such as phenylenediamine, diethyltoluenediamine, and 4,4′diaminodiphenylmethane; alicyclic diamines such as 4,4′-diamino-3,3′-dimethyldicyclohexylmethane, diaminecyclohexane, and isophoronediamine. ; Aliphatic diamines such as ethylenediamine, tetramethylenediamine, hexamethylenediamine and the like may be mentioned, and two or more kinds may be used in combination.

  Examples of the triamine or higher polyamine include diethylenetriamine and triethylenetetramine, and two or more kinds may be used in combination.

  Examples of amino alcohols include ethanolamine and hydroxyethylaniline, and two or more kinds may be used in combination.

  Examples of amino mercaptans include aminoethyl mercaptan and aminopropyl mercaptan, and two or more of them may be used in combination.

  Examples of amino acids include aminopropionic acid and aminocaproic acid, and two or more amino acids may be used in combination.

  Instead of the compound having an amino group, a compound having an amino group blocked with a ketone such as acetone, methyl ethyl ketone, or methyl isobutyl ketone may be used.

  The molar ratio of the isocyanate group to the amino group when adding the polyester prepolymer having an isocyanate group and the compound having an amino group is usually 0.5 to 2, preferably 2/3 to 1.5, preferably 5 / 6 to 1.2 is more preferable. When this molar ratio is less than 0.5 or more than 2, the molecular weight of the urea-modified polyester becomes small, and the hot offset resistance of the toner may be lowered.

  When adding a polyester prepolymer having an isocyanate group and a compound having an amino group, the molecular weight of the urea-modified polyester may be adjusted using a monoamine.

  Examples of monoamines include diethylamine, dibutylamine, butylamine, and laurylamine.

  Instead of monoamine, a monoamine having an amino group blocked with a ketone such as acetone, methyl ethyl ketone, or methyl isobutyl ketone may be used.

  It is preferable that at least a part of the urea-modified polyester and the amorphous polyester are compatible. That is, the composition of the polyester component in the urea-modified polyester and the amorphous polyester are preferably similar. Thereby, the low-temperature fixability and hot offset resistance of the toner can be improved.

  The mass ratio of the urea-modified polyester to the amorphous polyester is usually 5/95 to 75/25, preferably 10/90 to 25/75, more preferably 12/88 to 25/75, and 12/88 to 22/78 is particularly preferred. If this mass ratio is less than 5/95, the hot offset resistance of the toner may be reduced, and it may be difficult to achieve both heat-resistant storage stability and low-temperature fixability. The low-temperature fixability of the ink may deteriorate.

  The core may further contain a modified polyester other than urea-modified polyester such as urethane-modified polyester.

  The colorant is not particularly limited as long as it is a dye or a pigment, but carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow Lead, Titanium Yellow, Polyazo Yellow, Oil Yellow, Hansa Yellow (GR, A, RN, R), Pigment Yellow L, Benzidine Yellow (G, GR), Permanent Yellow (NCG), Vulcan Fast Yellow (5G, R) , Tartrazine rake, quinoline yellow rake, anthrazan yellow BGL, isoindolinone yellow, bengara, red lead, lead vermilion, cadmium red, cadmium mercurial red, antimon vermilion, permanent red 4R, para red, phise red, parachloro ortho Nitroani Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Tolujing Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thio Indigo Red B, Thioindigo Maroon, Oil Red, Quinacridone Red, Pyrazolone Red, Poly Zored, Chrome Vermilion, Benzidine Orange, Perinone Orange, Oil Orange, Cobalt Blue, Cerulean Blue, Alkaline Blue Lake, Peacock Blue Lake, Victoria Blue Lake, Metal-Free Phthalocyanine Blue, Phthalocyanine Blue, Fast Sky Blue, Indanthrene Blue (RS, BC), indigo, ultramarine blue, bitumen, anthraquinone blue, fast violet B, methyl violet lake, cobalt purple, manganese purple, dioxane violet, anthraquinone violet, chrome green, zinc green, chromium oxide, pyridian, emerald green, pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Lake, Phthalocyani N, Green, Anthraquinone Green, Titanium Oxide, Zinc Hana, Litobon, etc., may be used in combination.

  The content of the colorant in the toner is usually 1 to 15% by mass, and preferably 3 to 10% by mass.

  The pigment may be combined with a resin and used as a master batch.

  Although it does not specifically limit as resin, The above-mentioned amorphous polyester and urea modified polyester; Styrene, such as polystyrene, poly p-chlorostyrene, polyvinyltoluene, and its substituted polymer; Styrene-p-chlorostyrene copolymer Styrene-propylene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer Styrene-octyl acrylate copolymer, styrene-methyl methacrylate copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene -Acrylonitrile copolymer, styrene -Styrene such as vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester copolymer Copolymer: polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid, rosin, modified rosin, Examples include terpene resins, aliphatic or alicyclic hydrocarbon resins, aromatic petroleum resins, chlorinated paraffins, paraffin waxes, and the like.

  The master batch is obtained by mixing and kneading the pigment and the resin. At this time, an organic solvent can be used in order to improve the interaction between the pigment and the resin.

  The master batch is prepared by mixing and kneading an aqueous pigment paste together with a resin and an organic solvent using a flushing method, transferring the pigment to the resin side, and then removing moisture and the organic solvent. Can do. At this time, since the wet pigment cake can be used as it is, it is not necessary to prepare the pigment by drying the wet pigment cake.

  In addition, when mixing and kneading the pigment and the resin, a high shearing dispersion device such as a three-roll mill can be used.

  The release agent is not particularly limited, but includes polyolefin waxes such as polyethylene wax and polypropylene wax; long-chain hydrocarbons such as paraffin wax and sazol wax; waxes having a carbonyl group; Also good. Among these, a wax having a carbonyl group is preferable.

  Examples of the wax having a carbonyl group include carnauba wax, montan wax, trimethylolpropane tribehenate, pentaerythritol tetrabehenate, pentaerythritol diacetate dibehenate, glycerin tribehenate, and 1,18-octadecanediol diester. Polyalkanoic acid esters such as stearate; Polyalkanol esters such as tristearyl trimellitic acid and distearyl maleate; Polyalkanoic acid amides such as ethylenediamine dibehenyl amide; Polyalkylamides such as trimellitic acid tristearyl amide; Distearyl Examples thereof include dialkyl ketones such as ketones, among which polyalkanoic acid esters are preferable.

  The melting point of the release agent is usually 40 to 160 ° C, preferably 50 to 120 ° C, and more preferably 60 to 90 ° C. When the melting point of the release agent is less than 40 ° C., the heat resistant storage stability of the toner may be lowered, and when it exceeds 160 ° C., cold offset may occur when fixing at a low temperature.

  In general, the melt viscosity at a temperature 20 ° C. higher than the melting point of the release agent is preferably 5 to 1000 cps, and more preferably 10 to 100 cps. If the melt viscosity at a temperature 20 ° C. higher than the melting point of the release agent is less than 5 cps, the dispersibility of the release agent in the core may be lowered. If it exceeds 1000 cps, the hot offset resistance and low-temperature fixability of the toner May decrease.

  The content of the release agent in the toner is usually 0 to 40% by mass, and preferably 3 to 30% by mass.

  The resin contained in the shell is not particularly limited as long as it can be dispersed in an aqueous medium described later, but a vinyl resin or polyester is preferable.

  Examples of vinyl resins include acrylic acid, methacrylic acid, α-cyanoacrylic acid, α-cyanomethacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, maleic anhydride, and other acids; β-hydroxyethyl acrylate, methacrylic acid Β-hydroxyethyl acid, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate, γ-hydroxypropyl acrylate, γ-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl acrylate, methacrylic acid 3 -Chloro-2-hydroxypropyl, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, glycerol monoacrylate, glycerol monomethacrylate, N-methylol acrylamide, N-methylol methacrylate (Meth) acrylic monomers containing hydroxyl groups such as rilamide; vinyl alcohol; ethers with vinyl alcohol such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether; vinyl acetate, vinyl propionate, vinyl butyrate, etc. Esters of vinyl alcohol and carboxylic acid; acrylamide, methacrylamide, diacetone acrylamide, methylolated products thereof; acid chlorides such as acrylic acid chloride and methacrylic acid chloride; nitrogen such as vinyl pyridine, vinyl pyrrolidone, vinyl imidazole and ethylene imine Homopolymers or copolymers such as those having an atom or a heterocyclic ring thereof may be mentioned.

  Examples of the polyester include the above-described crystalline polyester and amorphous polyester.

  In order to disperse the resin contained in the shell in the aqueous medium, acid treatment or alkali treatment may be performed.

  The glass transition point of the resin contained in the shell is usually 40 to 100 ° C. When the glass transition point of the resin contained in the shell is less than 40 ° C., the heat-resistant storage stability of the toner may be lowered, and when it exceeds 100 ° C., the low-temperature fixability of the toner may be lowered.

The weight average molecular weight of the resin contained in the shell is usually 3 × 10 ^{3 to} 3 × 10 ⁵ . When the weight average molecular weight of the resin contained in the shell is less than 3 × 10 ³ , the heat-resistant storage stability of the toner may be lowered, and when it exceeds 3 × 10 ⁵ , the low-temperature fixability of the toner may be lowered. .

  The content of the resin contained in the shell in the toner is usually 0.5 to 5.0% by mass. When the content of the resin contained in the shell in the toner is less than 0.5% by mass, the heat resistant storage stability of the toner may be reduced. When the content exceeds 5.0% by mass, the hot offset resistance of the toner is decreased. May decrease.

  The content of the resin contained in the shell in the toner is caused by the resin contained in the shell using a pyrolysis gas chromatograph mass spectrometer, and is not caused by the material constituting the toner other than the resin contained in the shell. The substance can be analyzed and calculated from its peak area.

  The core may further include a charge control agent and the like.

  The charge control agent is not particularly limited, but nigrosine dye, triphenylmethane dye, chromium-containing metal complex dye, molybdate chelate pigment, rhodamine dye, alkoxy amine, quaternary ammonium salt (fluorine-modified quaternary ammonium salt) Salt), alkylamide, phosphorus simple substance or compound, tungsten simple substance or compound, fluorine-based surfactant, salicylic acid metal salt, salicylic acid derivative metal salt, copper phthalocyanine, perylene, quinacridone, azo pigment, etc. Two or more kinds may be used in combination. Examples of the charge control agent other than these include polymer compounds having a functional group such as a sulfonic acid group, a carboxyl group, and a quaternary ammonium base.

  Commercially available charge control agents include Nigrosine dye Bontron 03, quaternary ammonium salt Bontron P-51, metal-containing azo dye Bontron S-34, oxynaphthoic acid metal complex E-82, salicylic acid metal Complex E-84, phenolic condensate E-89 (above, Orient Chemical Industries); quaternary ammonium salt molybdenum complex TP-302, TP-415 (above, Hodogaya Chemical Co., Ltd.), 4 Quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, copy charge NX VP434 (from Hoechst), LRA-901, boron complex LR- 147 (made by Nippon Carlit Co., Ltd.).

  The content of the charge control agent in the toner is usually 0 to 10%, preferably 0.2 to 5%, based on the total mass of the crystalline polyester and the amorphous polyester. When the content of the charge control agent in the toner exceeds 10% with respect to the total mass of the crystalline polyester and the amorphous polyester, the chargeability of the toner is too large and the electrostatic attraction with the developing roller increases. In addition, the fluidity of the toner may be reduced and the image density may be reduced.

  In consideration of controlling the viscoelastic properties of the toner, the shell preferably further contains polylactic acid.

  The base particles are prepared by dissolving or dispersing a toner material including crystalline polyester, amorphous polyester, polyester prepolymer having an isocyanate group, a compound having an amino group, a colorant, and a release agent in an organic solvent. After emulsification or dispersion in an aqueous medium containing particles containing a resin, it can be formed by removing the organic solvent. At this time, the toner material may further contain a charge control agent and the like.

  The aqueous medium is not particularly limited, and examples thereof include water, a solvent that can be mixed with water, and a mixed solvent of water.

  Solvents miscible with water are not particularly limited, but alcohols such as methanol, isopropanol and ethylene glycol, cellsolves such as dimethylformamide, tetrahydrofuran and methylcellosolve, lower ketones such as acetone and methylethylketone, etc. 2 or more may be used in combination.

  When emulsifying or dispersing a liquid obtained by dissolving or dispersing a toner material in an organic solvent in an aqueous medium, a low-speed shear disperser, a high-speed shear disperser, a friction disperser, a high-pressure jet disperser, A disperser such as a sonic disperser can be used, but a high-speed shearing disperser is preferable in order to make the particle size of the dispersion 2 to 20 μm.

When using a high-speed shearing disperser, the number of rotations is usually 1 × 10 ^{3 to} 3 × 10 ⁴ rpm, preferably 5 × 10 ³ to 2 × 10 ⁴ rpm. The dispersion time is usually 0.1 to 5 minutes in the case of a batch method. Moreover, the temperature at the time of dispersion | distribution is 0-150 degreeC (under pressure) normally, and 40-98 degreeC is preferable. At this time, when the temperature at the time of dispersion is higher, the viscosity of the liquid obtained by emulsifying or dispersing the liquid obtained by dissolving or dispersing the toner material in the organic solvent in the aqueous medium decreases, and the dispersion becomes easier. .

  The toner material other than the polyester prepolymer having an isocyanate group may be added and mixed when a solution obtained by dissolving or dispersing the toner material in an organic solvent is emulsified or dispersed in an aqueous medium.

  Further, after forming the base particles not containing the colorant, the colorant may be added by a known dyeing method.

  The mass ratio of the aqueous medium to the toner material is usually from 0.5 to 20, and preferably from 1 to 10. If the mass ratio of the aqueous medium to the toner material is less than 0.5, the dispersion state of the toner material may be deteriorated, and base particles having a predetermined particle diameter may not be obtained. .

  The aqueous medium may further contain a surfactant and a dispersant such as an inorganic compound hardly soluble in water. Accordingly, the dispersion stability of a liquid obtained by emulsifying or dispersing a liquid obtained by dissolving or dispersing a toner material in an organic solvent in an aqueous medium can be improved, and the particle size distribution of the toner can be narrowed.

  The surfactant is not particularly limited, but anionic surfactants such as alkylbenzene sulfonates, α-olefin sulfonates and phosphate esters; alkylamine salts, aminoalcohol fatty acid derivatives, polyamine fatty acid derivatives, imidazolines and the like. Cationic surfactants such as amine salt type, alkyltrimethylammonium salt, dialkyldimethylammonium salt, alkyldimethylbenzylammonium salt, pyridinium salt, alkylisoquinolinium salt, quaternary ammonium salt type such as benzethonium chloride; fatty acid amide Nonionic surfactants such as derivatives and polyhydric alcohol derivatives; amphoteric boundaries such as alanine, dodecylbis (aminoethyl) glycine, bis (octylaminoethyl) glycine, N-alkyl-N, N-dimethylammonium betaine Active agents. Among these, a surfactant having a fluoroalkyl group is preferable because the addition amount can be very small.

  Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms and a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl (C6 to C11) oxy. ] Sodium 1-alkyl (C3-C4) sulfonate, sodium 3- [ω-fluoroalkanoyl (C6-C8) -N-ethylamino] -1-propanesulfonate, fluoroalkyl (C11-C20) carboxylic acid and Metal salts, perfluoroalkyl carboxylic acids (C7 to C13) and their metal salts, perfluoroalkyl (C4 to C12) sulfonic acids and their metal salts, perfluorooctane sulfonic acid diethanolamide, N-propyl-N- (2- Hydroxyethyl) perfluorooctane Examples include honamide, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (C6-C10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (C6-C16) ethyl phosphate, and the like.

  Commercially available anionic surfactants having a fluoroalkyl group include Surflon S-111, S-112, S-113 (Asahi Glass Co., Ltd.), Florard FC-93, FC-95, FC-98, FC-129. (Manufactured by Sumitomo 3M), Unidyne DS-101, DS-102 (manufactured by Daikin Industries, Ltd.), MegaFuck F-110, F-120, F-113, F-191, F-812, F-833 (Dainippon) Ink Co., Ltd.), Ectop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products), Footent F-100, F-150 (Neos) Etc.).

  The anionic surfactant having a fluoroalkyl group is not particularly limited, but an aliphatic primary, secondary or tertiary amino acid having a fluoroalkyl group, perfluoroalkyl (C6-C10) sulfonamidopropyltrimethylammonium salt. Aliphatic quaternary ammonium salts such as benzalkonium salt, benzethonium chloride, pyridinium salt, imidazolinium salt and the like.

  Commercially available anionic surfactants having a fluoroalkyl group include Surflon S-121 (Asahi Glass Co., Ltd.), Florard FC-135 (Sumitomo 3M Co., Ltd.), Unidyne DS-202 (Daikin Kogyo Co., Ltd.), Mega Fuck F-150, F-824 (Dainippon Ink Co., Ltd.), Xtop EF-132 (Tochem Products Co., Ltd.), Footent F-300 (Neos Co., Ltd.) and the like can be mentioned.

  The inorganic compound hardly soluble in water is not particularly limited, and examples thereof include tricalcium phosphate, calcium carbonate, titanium oxide, colloidal silica, and hydroxyapatite.

  In the case of using a dispersant, host particles with the dispersant remaining on the surface can be used, but considering the chargeability of the toner, it is preferable to use host particles from which the dispersant has been removed by washing. For example, when an acid such as calcium phosphate or an alkali-soluble compound is used as the dispersant, the calcium phosphate can be removed from the base particles by dissolving the calcium phosphate with an acid such as hydrochloric acid and then washing with water. . In addition, calcium phosphate can be removed from the base particles by decomposing with an enzyme.

  Although it does not specifically limit as a method of removing an organic solvent, The method of volatilizing an organic solvent using a rotary evaporator etc. is mentioned.

  After removing the organic solvent, the fine particles are removed by centrifugation, washed in a washing tank, and dried using a hot air dryer to obtain base particles.

  At this time, it is preferable to age after removing the organic solvent. The aging temperature is usually 30 to 55 ° C, preferably 40 to 50 ° C. The aging time is usually 5 to 36 hours, preferably 10 to 24 hours.

  Other methods for removing the organic solvent include using a spray dryer, belt dryer, rotary kiln, etc., and a solution obtained by emulsifying or dispersing a solution obtained by dissolving or dispersing a toner material in an organic solvent in an aqueous medium. A method in which the organic solvent and the aqueous medium are volatilized by spraying inside is mentioned. Although it does not specifically limit as dry atmosphere, The air heated to the temperature beyond the boiling point of an organic solvent and an aqueous medium, nitrogen, a carbon dioxide gas, combustion gas, etc. are mentioned.

  When the particle size distribution of the base particles is wide, the fine particles can be removed by a cyclone, a decanter, centrifugation, or the like.

  Next, the base particles and the fluidity improver are mixed using a Henschel mixer or the like, and the fluidity improver is fixed to the surface of the base particles. At this time, after fixing the fluidity improver on the surface of the base particles, the coarse particles can be removed by ultrasonic sieving or the like.

  Although it does not specifically limit as a fluid improvement agent, An inorganic particle, the inorganic particle hydrophobized, etc. are mentioned, You may use 2 or more types together.

  The average particle diameter of the primary particles of the fluidity improver is usually 1 to 100 nm, preferably 3 to 70 nm. If the average particle size of the primary particles of the fluidity improver is less than 1 nm, the fluidity improver may be embedded in the base particles, and if it exceeds 100 nm, the surface of the photoreceptor may be damaged unevenly during development. There is.

  The fluidity improver preferably includes those having an average primary particle size of 20 nm or less and those having an average primary particle size of 30 nm or more.

The BET specific surface area of the fluidity improver is usually 20 to 500 m ² / g.

  The inorganic particles are not particularly limited, but silica, alumina, titania, barium titanate, magnesium titanate, calcium titanate, strontium titanate, iron oxide, copper oxide, zinc oxide, tin oxide, silica sand, clay, mica , Wollastonite, diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, silicon carbide, silicon nitride, etc. May be. Of these, silica and titania are preferable.

  Examples of commercially available silica particles include HDK H 2000, HDK H 2000/4, HDK H 2050EP, HVK21, HDK H 1303 (manufactured by Hoechst), R972, R974, RX200, RY200, R202, R805, R812 (and above). , Manufactured by Nippon Aerosil Co., Ltd.).

  Commercially available titania particles include P-25 (manufactured by Nippon Aerosil Co., Ltd.), STT-30, STT-65C-S (above, manufactured by Titanium Industry Co., Ltd.), TAF-140 (manufactured by Fuji Titanium Industry Co., Ltd.), MT-150W. , MT-500B, MT-600B, MT-150A (manufactured by TEIKA CORPORATION) and the like.

  By subjecting the inorganic particles to a hydrophobic treatment, it is possible to suppress a decrease in toner flow characteristics and charging characteristics even under high humidity.

  The treatment agent for hydrophobizing inorganic particles is not particularly limited, but includes silane coupling agents such as methyltrimethoxysilane, methyltriethoxysilane, and octyltrimethoxysilane, silylating agents, and silane cups having a fluorinated alkyl group. Examples thereof include a ring agent, an organic titanate coupling agent, an aluminum coupling agent, and silicone oil.

  The silicone oil is not particularly limited, but dimethyl silicone oil, methylphenyl silicone oil, chlorophenyl silicone oil, methyl hydrogen silicone oil, alkyl-modified silicone oil, fluorine-modified silicone oil, polyether-modified silicone oil, alcohol-modified silicone oil, Amino-modified silicone oil, epoxy-modified silicone oil, epoxy-polyether-modified silicone oil, phenol-modified silicone oil, carboxyl-modified silicone oil, mercapto-modified silicone oil, (meth) acryl-modified silicone oil, α-methylstyrene-modified silicone oil, etc. Can be mentioned.

  Examples of the titania particles subjected to hydrophobic treatment include T-805 (manufactured by Nippon Aerosil Co., Ltd.), STT-30A, STT-65S-S (manufactured by Titanium Kogyo Co., Ltd.), TAF-500T, TAF-1500T (manufactured by Fuji Titanium). Kogyo Co., Ltd.), MT-100S, MT-100T (above, manufactured by Teika), IT-S (Ishihara Sangyo Co., Ltd.) and the like.

  The content of the fluidity improver in the toner is usually 0.1 to 5% by mass, preferably 0.3 to 3% by mass.

  In the present invention, a cleaning property improver may be added when the base particles and the fluidity improver are mixed.

  The cleaning property improver is not particularly limited, but fatty acid metal salts such as zinc stearate and calcium stearate; polycondensation systems such as polystyrene, (meth) acrylic acid ester copolymers, silicone resins, benzoguanamine and nylon, and thermosetting. Resin particles such as a conductive resin.

  The resin particles can be produced by soap-free emulsion polymerization, suspension polymerization, dispersion polymerization or the like, and preferably have a relatively narrow particle size distribution and a volume average particle size of 0.01 to 1 μm.

  The toner of the present invention preferably has an average circularity of 0.93 to 0.99. If the average circularity of the toner of the present invention is less than 0.93, the transferability of the toner may be deteriorated and a high-quality image may not be obtained. If the average circularity exceeds 0.99, cleaning is performed with a photoreceptor or a transfer belt. Defects may occur.

  The average circularity of the toner is measured by using a flow particle image analyzer FPIA-2100 (manufactured by Sysmex Corporation), and is calculated by analysis using analysis software FPIA-2100 Data Processing Program for FPIA version 00-10. can do.

  The toner of the present invention preferably has a shape factor SF-1 of 100 to 150. When the shape factor SF-1 of the toner of the present invention exceeds 150, the shape of the toner is deformed, and the movement of the toner when transferring the toner image is not smooth, and the behavior of the toner varies. High transfer efficiency cannot be obtained. Further, in addition to unstable charging of the toner, the toner may become brittle. As a result, the toner becomes fine powder in the developer, which causes a decrease in the durability of the developer.

  The toner of the present invention preferably has a shape factor SF-2 of 100 to 140. When the shape factor SF-2 of the toner of the present invention exceeds 140, toner transferability may be insufficient.

  SF-1 and SF-2 sampled 300 toners randomly from a photograph taken using a field emission type operation electron microscope S-4200 (manufactured by Hitachi, Ltd.), It can be calculated by introducing into an image analyzing apparatus Luzex AP (manufactured by Nireco) via an interface and analyzing.

  The toner of the present invention preferably has a weight average particle diameter of 2 to 7 μm, more preferably 2 to 5 μm. When the weight average particle size of the toner of the present invention is less than 2 μm, the toner may be fused to the surface of the carrier due to long-term agitation in the developing device, and the charging ability of the carrier may be reduced. It becomes difficult to form a high-resolution and high-quality image, and when the balance of the toner in the developer is performed, the variation in the particle size of the toner may become large.

  In the toner of the present invention, the ratio of the weight average particle diameter to the number average particle diameter is preferably 1.00 to 1.25, and more preferably 1.00 to 1.15. When the ratio of the weight average particle diameter to the number average particle diameter of the toner of the present invention exceeds 1.25, the behavior of the toner varies during development, and the reproducibility of minute dots decreases, resulting in a high quality image. It may not be possible.

  The weight average particle diameter and number average particle diameter of the toner can be measured using Coulter Multisizer II (manufactured by Coulter Inc.).

  The glass transition point of the toner of the present invention is usually 40 to 70 ° C., preferably 45 to 55 ° C. When the glass transition point is less than 40 ° C., the heat-resistant storage stability of the toner may be lowered, and when it exceeds 70 ° C., the low-temperature fixability of the toner may be lowered.

The temperature TG ′ at which the storage elastic modulus is 1 × 10 ⁴ dyne / cm ² when the frequency of the toner of the present invention is 20 Hz is usually 100 ° C. or higher, and preferably 110 to 200 ° C. If TG ′ is less than 100 ° C., the hot offset resistance of the toner may be lowered.

The temperature Tη at which the viscosity is 1 × 10 ³ poise when the frequency of the toner of the present invention is 20 Hz is usually 180 ° C. or less, and preferably 90 to 160 ° C. When Tη exceeds 180 ° C., the low-temperature fixability of the toner may deteriorate.

  TG′-Tη is usually 0 to 100 ° C., preferably 10 to 90 ° C., more preferably 20 to 80 ° C. If TG′−Tη is less than 0 ° C., it may be difficult to achieve both low-temperature fixability and hot offset resistance of the toner, and if it exceeds 100 ° C., the heat-resistant storage stability of the toner may be reduced. is there.

  The developer of the present invention has the toner and carrier of the present invention, and the mass ratio of the toner to the carrier is preferably 1 to 10%.

  The carrier is not particularly limited, and examples thereof include iron powder, ferrite powder, and magnetite powder having a particle size of 20 to 200 μm.

  The surface of the carrier may be coated with a resin. Examples of such resins include, but are not limited to, urea-formaldehyde resins, melamine resins, benzoguanamine resins, urea resins, polyamide resins, epoxy resins and other amino resins; polymethyl methacrylate, polyacrylonitrile and other acrylic resins; Polyvinyl alcohol resins such as vinyl acetate, polyvinyl alcohol and polyvinyl butyral; Polystyrene resins such as polystyrene and styrene-acrylic copolymers; Halogenated olefins such as polyvinyl chloride; Polyesters such as polyethylene terephthalate and polybutylene terephthalate; Polycarbonates; Polyethylene: Polyvinyl fluoride, polyvinylidene fluoride, polytrifluoroethylene, polyhexafluoropropylene, copolymer of vinylidene fluoride and acrylic monomer A copolymer of vinylidene fluoride and vinyl fluoride, fluorine resin terpolymers, etc. of tetrafluoroethylene and vinylidene fluoride and non-fluorinated monomer; and silicone resins.

  Such a resin may contain conductive powder or the like. The conductive powder is not particularly limited, and examples thereof include metal powder, carbon black, titanium oxide, tin oxide, and zinc oxide.

  The conductive powder preferably has an average particle size of 1 μm or less. When the average particle size exceeds 1 μm, it may be difficult to control the electric resistance.

  FIG. 5 shows an example of an image forming apparatus used in the present invention. The image forming apparatus 100 is a tandem color image forming apparatus, and includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

  The intermediate transfer belt 50 provided at the center of the copying apparatus main body 150 is an endless belt stretched around three rollers 14, 15 and 16, and can move in the direction of the arrow in the figure. In the vicinity of the roller 15, a cleaning device 90 having a cleaning blade for removing the toner remaining on the intermediate transfer belt 50 on which the toner image is transferred onto the recording paper is disposed. The image forming units 120Y, 120C, 120M, and 120K for yellow, cyan, magenta, and black are juxtaposed along the conveyance direction while facing the intermediate transfer belt 50 stretched by the rollers 14 and 15. An exposure device 30 is disposed in the vicinity of the image forming unit 120. Further, the transfer belt 24 is disposed on the side of the intermediate transfer belt 50 opposite to the side on which the image forming unit 120 is disposed. The transfer belt 24 is an endless belt stretched around a pair of rollers 22 and 23, and the recording paper conveyed on the transfer belt 24 and the intermediate transfer belt 50 are in contact between the rollers 16 and 22. be able to. Also, a fixing device 25 including a fixing belt 26 that is an endless belt stretched around a pair of rollers and a pressure roller 27 that is pressed against the fixing belt 26 is disposed in the vicinity of the transfer belt 24. Has been. A sheet reversing device 28 for reversing the recording paper when an image is formed on both sides of the recording paper is disposed in the vicinity of the transfer belt 24 and the fixing device 25.

The fixing device 25 fixes the toner image by pressing and heating the recording paper on which the toner image is transferred with a surface pressure of 1 × 10 ^{5 to} 3 × 10 ⁷ Pa for 0.03 to 0.4 seconds. When the surface pressure for pressing the recording paper is less than 1 × 10 ⁵ Pa, the toner image is not sufficiently fixed when the toner image is fixed at a low temperature, and when it exceeds 3 × 10 ⁷ Pa, the recording paper is curled. Or the image quality deteriorates. If the time for pressurizing the recording paper is less than 0.03 seconds, the toner image is not sufficiently fixed, and if it exceeds 0.4 seconds, hot offset is likely to occur.

  The system speed is preferably 0.2 to 3 m / s. If the system speed is less than 0.2 m / s, an image cannot be formed at a high speed, and hot offset tends to occur. On the other hand, when the system speed exceeds 3 m / s, the toner image is not sufficiently fixed.

  The surface pressure for pressing the recording paper can be measured using a pressure distribution measuring device PINCH (manufactured by Nitta).

  The time for pressing the recording medium is a ratio of the fixing nip width to the system speed.

Further, the system speed v [m / s] is measured by measuring the time t [s] required to form 100 images continuously by passing A4 paper in the vertical direction, and the equation v = 100 × 0. 297 / t
It is requested from. The A4 paper has a length of 0.297 m in the vertical direction.

  Next, a method for forming a full-color image using the image forming apparatus 100 will be described. First, a color document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and a color document is set on the contact glass 32 of the scanner 300 to automatically convey the document. The device 400 is closed. When a start switch (not shown) is pressed, when an original is set on the automatic document feeder 400, the original is conveyed and moved onto the contact glass 32, and then the original is set on the contact glass 32. In this case, the scanner 300 is immediately driven, and the first traveling body 33 including the light source and the second traveling body 34 including the mirror travel. At this time, the reflected light from the original surface of the light irradiated from the first traveling body 33 is reflected by the second traveling body 34 and then received by the reading sensor 36 via the imaging lens 35, whereby the original is received. It is read and image information of black, yellow, magenta and cyan is obtained.

  The image information for each color is transmitted to the image forming unit 120 for each color, and a toner image for each color is formed. As shown in FIG. 6, each color image forming unit 120 develops the photosensitive drum 10, the charging roller 20 for uniformly charging the photosensitive drum 10, and the electrostatic latent image with each color developer. A developing device 40 for forming toner images of respective colors, a transfer roller 80 for transferring the toner image onto the intermediate transfer belt 50, a cleaning device 60 having a cleaning blade, and a charge eliminating lamp 70.

  The toner images of the respective colors formed by the image forming units 120 of the respective colors are sequentially transferred (primary transfer) onto the intermediate transfer body 50 that is stretched and moved by the rollers 14, 15, and 16, and superimposed to form a composite toner image. It is formed.

  On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed recording paper from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop. Alternatively, the paper feed roller 51 is rotated to feed out the recording paper on the manual feed tray 54, separated one by one by the separation roller 52, guided to the manual paper feed path 53, and abutted against the registration roller 49 and stopped. The registration roller 49 is generally used while being grounded, but a bias may be applied to remove paper dust from the recording paper. Next, by rotating the registration roller 49 in synchronization with the composite toner image formed on the intermediate transfer belt 50, the recording paper is sent between the intermediate transfer belt 50 and the transfer belt 24, and the composite toner image is sent. Is transferred onto the recording paper (secondary transfer). The toner remaining on the intermediate transfer belt 50 to which the composite toner image has been transferred is removed by the cleaning device 90.

  The recording paper onto which the composite toner image has been transferred is conveyed by the transfer belt 24 and then the composite toner image is fixed by the fixing device 25. Next, the conveyance path of the recording paper is switched by the switching claw 55, and the recording paper is discharged onto the paper discharge tray 57 by the discharge roller 56. Alternatively, the recording path of the recording paper is switched by the switching claw 55, reversed by the sheet reversing device 28, an image is similarly formed on the back side, and then discharged onto the discharge tray 57 by the discharge roller 56. .

  The image forming apparatus 100 sequentially transfers (primary transfer) the toner images of the respective colors formed by the image forming units 120 of the respective colors onto the intermediate transfer body 50 and superimposes them, and then transfers them onto the recording paper (secondary transfer). However, it is also possible to use a direct transfer system in which the toner images of the respective colors formed by the image forming units 120 of the respective colors are sequentially transferred onto the recording paper and superimposed.

  Further, a transfer roller may be used instead of the transfer belt 24.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to this. Hereinafter, a part shows a mass part.

[Preparation of dispersion 1 of vinyl resin]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid , 60 parts of styrene, 100 parts of methacrylic acid, 70 parts of butyl acrylate, and 1 part of ammonium persulfate were stirred at 3.8 × 10 ³ rpm for 30 minutes, and then heated to 75 ° C. and reacted for 4 hours. Thereafter, 30 parts of a 1% by mass ammonium persulfate aqueous solution was added and aged at 75 ° C. for 6 hours to obtain a dispersion 1 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the dispersion 1 of vinyl resin was measured and found to be 280 nm. Moreover, when the vinyl resin contained in the dispersion liquid 1 of vinyl resin was isolated, the vinyl resin had a glass transition point of 59 ° C. and a weight average molecular weight of 6 × 10 ⁴ .

[Preparation of vinyl resin dispersion 2]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid Then, 60 parts of styrene, 100 parts of methacrylic acid, 70 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 3.8 × 10 ³ rpm for 20 minutes. Next, after raising the temperature to 75 ° C. and reacting for 3 hours, 30 parts of a 1% by mass aqueous ammonium persulfate solution was added and aged at 65 ° C. for 12 hours to obtain a dispersion 2 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the dispersion 2 of vinyl resin was measured and found to be 390 nm. Further, when the vinyl resin contained in the vinyl resin dispersion 2 was isolated, the vinyl resin had a glass transition point of 60 ° C. and a weight average molecular weight of 7 × 10 ⁴ .

[Preparation of dispersion 3 of vinyl resin]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid , 60 parts of styrene, 100 parts of methacrylic acid, 70 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 2.0 × 10 ³ rpm for 20 minutes. Next, after raising the temperature to 75 ° C. and reacting for 3 hours, 30 parts of a 1% by mass aqueous ammonium persulfate solution was added and aged at 65 ° C. for 12 hours to obtain a dispersion 3 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the vinyl resin dispersion 3 was measured and found to be 640 nm. Further, when the vinyl resin contained in the vinyl resin dispersion 3 was isolated, the vinyl resin had a glass transition point of 59 ° C. and a weight average molecular weight of 1.2 × 10 ⁵ .

[Preparation of dispersion 4 of vinyl resin]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid Then, 70 parts of styrene, 90 parts of methacrylic acid, 60 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 3.8 × 10 ³ rpm for 30 minutes. Next, after raising the temperature to 75 ° C. and reacting for 3 hours, 30 parts of a 1% by mass aqueous ammonium persulfate solution was added and aged at 75 ° C. for 6 hours to obtain a dispersion 4 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the dispersion 4 of vinyl resin was measured and found to be 153 nm. Further, when the vinyl resin contained in the dispersion 4 of vinyl resin was isolated, the vinyl resin had a glass transition point of 59 ° C. and a weight average molecular weight of 1.5 × 10 ⁵ .

[Preparation of dispersion 5 of vinyl resin]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid Then, 70 parts of styrene, 90 parts of methacrylic acid, 60 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 4.3 × 10 ³ rpm for 30 minutes. Next, after raising the temperature to 75 ° C. and reacting for 4 hours, 30 parts of a 1% by mass ammonium persulfate aqueous solution was added and aged at 75 ° C. for 6 hours to obtain a dispersion 5 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the vinyl resin dispersion 5 was measured to be 105 nm. Further, when the vinyl resin contained in the vinyl resin dispersion 5 was isolated, the vinyl resin had a glass transition point of 58 ° C. and a weight average molecular weight of 1.4 × 10 ⁵ .

[Preparation of dispersion 6 of vinyl resin]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid , 60 parts of styrene, 100 parts of methacrylic acid, 70 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 1.5 × 10 ³ rpm for 20 minutes. Next, after raising the temperature to 75 ° C. and reacting for 3 hours, 30 parts of a 1% by mass aqueous ammonium persulfate solution was added and aged for 12 hours at 65 ° C. to obtain a dispersion 6 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the dispersion 6 of vinyl resin was measured and found to be 720 nm. Further, when the vinyl resin contained in the vinyl resin dispersion 6 was isolated, the vinyl resin had a glass transition point of 57 ° C. and a weight average molecular weight of 1.2 × 10 ⁵ .

[Preparation of vinyl resin dispersion 7]
In a reaction vessel equipped with a stirring bar and a thermometer, a mixture of 200 parts of styrene, 120 parts of methyl methacrylate, 40 parts of n-butyl acrylate, 4 parts of acrylic acid, 24 parts of dodecanethiol and 4 parts of carbon tetrabromide, Non-ionic surfactant Nonipol 400 (manufactured by Sanyo Kasei Co., Ltd.) 6 parts and anionic surfactant Neogen SC (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 10 parts are emulsified using an aqueous solution in which ion-exchanged water 560 parts is dissolved. After that, an aqueous solution in which 4 parts of ammonium persulfate was dissolved in 50 parts of ion-exchanged water was added, the air in the reaction vessel was replaced with nitrogen by a decompression operation, and then the temperature was raised to 70 ° C. and reacted for 5 hours. A dispersion 7 of vinyl resin was obtained. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba Ltd.), the volume average particle size of the vinyl resin dispersion 7 was measured and found to be 180 nm. Further, when the vinyl resin contained in the vinyl resin dispersion 7 was isolated, the vinyl resin had a glass transition point of 73 ° C. and a weight average molecular weight of 1.5 × 10 ⁴ . Furthermore, the dispersion 7 of vinyl resin had a solid content of 40% by mass.

[Preparation of vinyl resin dispersion 8]
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts of ion-exchanged water, 11 parts of sodium salt Eleminol RS-30 (manufactured by Sanyo Chemical Industries) of sulfuric acid ester of methacrylic acid ethylene oxide, 10 parts of polylactic acid Then, 65 parts of styrene, 95 parts of methacrylic acid, 65 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 3.8 × 10 ³ rpm for 30 minutes. Next, after raising the temperature to 75 ° C. and reacting for 3 hours, 30 parts of a 1% by mass ammonium persulfate aqueous solution was added and aged at 75 ° C. for 6 hours to obtain a dispersion 8 of vinyl resin. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the vinyl resin dispersion 8 was measured to be 124 nm. When the vinyl resin contained in the vinyl resin dispersion 8 was isolated, the vinyl resin had a glass transition point of 60 ° C. and a weight average molecular weight of 1.6 × 10 ⁵ .

[Synthesis of Amorphous Polyester 1]
In a reaction vessel equipped with a condenser, a stirrer, and a nitrogen introduction tube, 229 parts of bisphenol A ethylene oxide 2 mol adduct, 339 parts of bisphenol A propylene oxide 3 mol adduct, 208 parts terephthalic acid, 80 parts adipic acid Then, 10 parts of succinic acid and 2 parts of dibutyltin oxide were added, reacted at 230 ° C. for 5 hours under normal pressure, and then reacted for 5 hours under reduced pressure of 10 to 15 mmHg. Next, 35 parts of trimellitic anhydride was added and reacted at 180 ° C. for 1 hour under normal pressure to obtain amorphous polyester 1. Amorphous polyester 1 had a number average molecular weight of 1.8 × 10 ³ , a weight average molecular weight of 3.5 × 10 ³ , a glass transition point of 38 ° C., and an acid value of 25 mgKOH / g.

[Synthesis of Amorphous Polyester 2]
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 430 parts of propylene oxide 2-mole adduct of bisphenol A, 300 parts of propylene oxide 3-mole adduct of bisphenol A, 257 parts of terephthalic acid, 65 parts of isophthalic acid Then, 10 parts of maleic anhydride and 2 parts of titanium dihydroxybis (triethanolamate) were added and reacted at 220 ° C. for 8 hours under a nitrogen stream. Next, it was made to react under the reduced pressure of 5-20 mmHg, it took out when the acid value became 7 mgKOH / g, and after cooling to room temperature, it grind | pulverized and the amorphous polyester 2 was obtained. Amorphous polyester 2 had a number average molecular weight of 6.2 × 10 ³ , a weight average molecular weight of 2.56 × 10 ⁴ , a glass transition point of 59 ° C., and an acid value of 8 mgKOH / g.

[Synthesis of Amorphous Polyester 3]
In a reaction vessel equipped with a condenser, a stirrer, and a nitrogen introduction tube, 350 parts of an acetylene oxide 2-mole adduct of bisphenol A, 326 parts of a propylene oxide 3-mole adduct of bisphenol A, 278 parts of terephthalic acid, phthalic anhydride 40 parts and 2 parts of titanium dihydroxybis (triethanolaminate) were added and reacted at 220 ° C. for 8 hours under a nitrogen stream. Next, the reaction is carried out under reduced pressure of 5 to 20 mmHg, and after cooling to 180 ° C. when the acid value becomes 2 mgKOH / g or less, 62 parts of trimellitic anhydride is added and the reaction is carried out for 2 hours under normal pressure sealing. I let you. Furthermore, after taking out, cooling to room temperature, it grind | pulverized and the amorphous polyester 3 was obtained. Amorphous polyester 3 had a number average molecular weight of 4.2 × 10 ³ , a weight average molecular weight of 9.38 × 10 ⁴ , a glass transition point of 68 ° C., and an acid value of 35 mgKOH / g.

[Synthesis of Amorphous Polyester 4]
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 229 parts of an ethylene oxide 2-mole adduct of bisphenol A, 329 parts of a propylene oxide 3-mole adduct of bisphenol A, 208 parts of terephthalic acid, 80 parts of adipic acid And 2 parts of dibutyltin oxide were added and reacted at 230 ° C. under normal pressure for 7 hours, and then allowed to react for 5 hours under reduced pressure of 10 to 15 mmHg. Next, 35 parts of trimellitic anhydride was added and reacted at 180 ° C. for 2 hours under normal pressure to obtain amorphous polyester 4. Amorphous polyester 4 had a number average molecular weight of 2.0 × 10 ³ , a weight average molecular weight of 3.8 × 10 ³ , a glass transition point of 40 ° C., and an acid value of 25 mgKOH / g.

[Synthesis of Amorphous Polyester 5]
In a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, 60 mol of an ethylene oxide 2 mol adduct of bisphenol A, 40 mol of ethylene glycol, 50 mol of terephthalic acid, and 50 mol of isophthalic acid are added. After replacing the air with nitrogen, 0.04 mol of dibutyltin oxide was added, and the mixture was reacted at 195 ° C. for 6 hours under a nitrogen gas stream. Next, after heating up to 240 degreeC and making it react for 6 hours, it was made to react under reduced pressure of 10 mmHg for 30 minutes, and the amorphous polyester 5 was obtained. Amorphous polyester 5 had a number average molecular weight of 5.0 × 10 ³ , a weight average molecular weight of 1.9 × 10 ⁴ , a glass transition point of 64 ° C., and an acid value of 16 mgKOH / g.

[Synthesis of Prepolymer 1]
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen introduction pipe, 682 parts of bisphenol A ethylene oxide 2-mole adduct, 81 parts of bisphenol A propylene oxide 2-mole adduct, 283 parts of terephthalic acid, trimellitic anhydride 22 parts of acid and 2 parts of dibutyltin oxide were added, reacted at 230 ° C. under normal pressure for 7 hours, and then reacted under reduced pressure of 10 to 15 mmHg for 5 hours to obtain a polyester 1 having a hydroxyl group. Polyester 1 having a hydroxyl group has a number average molecular weight of 2.2 × 10 ³ , a weight average molecular weight of 9.7 × 10 ³ , a glass transition point of 54 ° C., an acid value of 0.5 mgKOH / g, and a hydroxyl value of 52 mgKOH / g.

  Next, 410 parts of polyester 1 having a hydroxyl group, 89 parts of isophorone diisocyanate and 500 parts of ethyl acetate are placed in a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introduction pipe, and reacted at 100 ° C. for 5 hours. A prepolymer 1 was obtained. Prepolymer 1 had a free isocyanate content of 1.53% by mass.

[Synthesis of Ketimine 1]
In a reaction vessel equipped with a stir bar and a thermometer, 170 parts of isophoronediamine and 75 parts of methyl ethyl ketone were placed and reacted at 50 ° C. for 4 hours and half to obtain ketimine 1. Ketimine 1 had an amine value of 417 mg KOH / g.

[Synthesis of Crystalline Polyester 1]
After putting 1200 parts of 1,6-hexanediol, 1200 parts of 1,12-dodecanedicarboxylic acid and 0.4 parts of dibutyltin oxide in a reaction vessel in which a cooling tube, a stirrer and a nitrogen introduction tube were set, the operation was performed under reduced pressure. The air in the reaction vessel was replaced with nitrogen, and the mixture was stirred at 180 rpm for 5 hours by mechanical stirring. Next, the temperature was raised to 220 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When it became viscous, it was air-cooled to stop the reaction, thereby obtaining crystalline polyester 1. Crystalline polyester 1 had a number average molecular weight of 3.7 × 10 ³ , a weight average molecular weight of 1.6 × 10 ⁴ , and a melting point of 69 ° C.

[Synthesis of Crystalline Polyester 2]
After putting 124 parts of ethylene glycol, 22.2 parts of sodium dimethyl 5-sulfoisophthalate, 213 parts of dimethyl sebacate, and 0.3 part of dibutyltin oxide in a reaction vessel in which a condenser, a stirrer, and a nitrogen introduction tube are set. The air in the reaction vessel was replaced with nitrogen by a depressurization operation, and the mixture was stirred at 180 ° C. for 5 hours by mechanical stirring. Next, the temperature was raised to 220 ° C. under reduced pressure, and the mixture was stirred for 2 hours. When the mixture became viscous, it was air-cooled to stop the reaction, whereby crystalline polyester 2 was obtained. Crystalline polyester 2 had a number average molecular weight of 5.4 × 10 ³ , a weight average molecular weight of 9.7 × 10 ³ , and a melting point of 60 ° C.

[Amorphous polyester dispersion 1]
After mixing 80 parts of ion-exchanged water and 20 parts of amorphous polyester 5, the pH was adjusted to 8.5 using ammonia. Next, using a disperser in which Cavitron CD1010 (manufactured by Eurotech) is modified to a high temperature and high pressure type, the rotor rotation speed is 60 Hz, the pressure is 5 kgf / cm ² , and the heating by the heat exchanger is 140 ° C. Thus, a dispersion 1 of amorphous polyester was obtained. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the dispersion 1 of amorphous polyester was measured and found to be 150 nm. Further, the dispersion 1 of amorphous polyester had a solid content concentration of 30% by mass.

[Amorphous polyester dispersion 2]
After mixing 80 parts of ion-exchanged water and 20 parts of amorphous polyester 2, the pH was adjusted to 8.5 using ammonia. Next, using a disperser in which Cavitron CD1010 (manufactured by Eurotech) is modified to a high temperature and high pressure type, the rotor rotation speed is 60 Hz, the pressure is 5 kgf / cm ² , and the heating by the heat exchanger is 140 ° C. Thus, a dispersion 2 of amorphous polyester was obtained. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle diameter of the dispersion 2 of amorphous polyester was measured and found to be 201 nm. In addition, the amorphous polyester dispersion 2 had a solid content of 30% by mass.

[Amorphous polyester dispersion 3]
After mixing 80 parts of ion-exchanged water and 20 parts of amorphous polyester 2, the pH was adjusted to 8.5 using ammonia. Next, using a disperser obtained by modifying Cavitron CD1010 (manufactured by Eurotech) into a high-temperature and high-pressure type, the rotational speed of the rotor is 60 Hz, the pressure is 4 kgf / cm ² , and the heating by the heat exchanger is 140 ° C. Thus, a dispersion 3 of amorphous polyester was obtained. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the dispersion 3 of amorphous polyester was measured and found to be 293 nm. Further, the dispersion 3 of the amorphous polyester had a solid content concentration of 30% by mass.

[Amorphous polyester dispersion 4]
After mixing 80 parts of ion-exchanged water and 20 parts of amorphous polyester 5, the pH was adjusted to 8.5 using ammonia. Next, using a disperser obtained by modifying Cavitron CD1010 (manufactured by Eurotech) into a high-temperature and high-pressure type, the rotational speed of the rotor is 60 Hz, the pressure is 6 kgf / cm ² , and the heating by the heat exchanger is 140 ° C. Thus, a dispersion 4 of amorphous polyester was obtained. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the dispersion 4 of amorphous polyester was measured and found to be 103 nm. Further, the dispersion 4 of amorphous polyester had a solid content concentration of 30% by mass.

[Amorphous polyester dispersion 5]
After mixing 80 parts of ion-exchanged water and 20 parts of amorphous polyester 5, the pH was adjusted to 8.5 using ammonia. Next, using a disperser obtained by modifying Cavitron CD1010 (manufactured by Eurotech) into a high-temperature and high-pressure type, the rotation speed of the rotor is 60 Hz, the pressure is 5.5 kgf / cm ² , and the heating by the heat exchanger is 140 ° C. A dispersion 5 of amorphous polyester was obtained by dispersing. The volume average particle diameter of the dispersion 5 of amorphous polyester was measured using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba Ltd.), and it was 122 nm. The dispersion 5 of amorphous polyester had a solid content concentration of 30% by mass.

[Example 1]
990 parts of ion-exchanged water, 83 parts of vinyl resin dispersion 1, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 1 was obtained.

  Ion-exchanged water 1200 parts, DBP oil absorption 42 ml / 100 mg, pH 9.5 carbon black Printex 35 (made by Dexa) 540 parts and 1200 parts of amorphous polyester 1, Henschel mixer (made by Mitsui Mining) The mixture was mixed and kneaded at 110 ° C. for 1 hour using two rolls, then rolled and cooled, and pulverized using a pulverizer to obtain a master batch 1.

  378 parts of amorphous polyester 1, 120 parts of paraffin wax having a melting point of 90 ° C., 200 parts of crystalline polyester 1 and 947 parts of ethyl acetate are placed in a container equipped with a stirring bar and a thermometer while stirring. The temperature was raised to 80 ° C. and held for 5 hours, and then cooled to 30 ° C. in 1 hour. Next, 500 parts of Masterbatch 1 and 500 parts of ethyl acetate were added and mixed for 1 hour. 1324 parts of the obtained mixed liquid was transferred to a container, and using a bead mill Ultra Visco Mill (manufactured by Imex Co., Ltd.), the liquid feeding speed was 1 kg / h, the peripheral speed of the disk was 6 m / s, and the particle size was 0.00. 80% by volume of 5 mm zirconia beads were filled and dispersed under conditions of 3 passes. Next, 1324 parts of a 65 mass% ethyl acetate solution of amorphous polyester 1 was added, and the mixture was dispersed under the conditions of two passes in the same manner as described above using a bead mill Ultraviscomil (manufactured by Imex). Dispersion 1 was obtained. When dispersion 1 was dried at 130 ° C. for 30 minutes, the solid content concentration was 50% by mass.

749 parts of dispersion 1, 120 parts of prepolymer 1 and 3.5 parts of ketimine 1 are placed in a container, and 5 times at 5 × 10 ³ rpm using a TK homomixer (manufactured by Tokushu Kika). After mixing for 1 minute, 1200 parts of the aqueous medium 1 was added and mixed for 1.5 hours at 1 × 10 ⁴ rpm using a TK homomixer to obtain an emulsified slurry 1.

  The emulsified slurry 1 was put in a container in which a stirrer and a thermometer were set, and after removing the solvent at 30 ° C. for 8 hours, it was aged at 40 ° C. for 72 hours to obtain a dispersed slurry 1.

After 100 parts of the dispersion slurry 1 were filtered under reduced pressure, 100 parts of ion-exchanged water was added to the filter cake, and the mixture was mixed for 10 minutes at 1.2 × 10 ⁴ rpm using a TK homomixer, followed by filtration. To the obtained filter cake, 100 parts of a 10% by mass aqueous sodium hydroxide solution was added, mixed at 1.2 × 10 ⁴ rpm for 30 minutes using a TK homomixer, and then filtered under reduced pressure. 100 parts of 10% by mass hydrochloric acid was added to the obtained filter cake, mixed for 10 minutes at 1.2 × 10 ⁴ rpm using a TK homomixer, and then filtered. After adding 300 parts of ion-exchanged water to the obtained filter cake and mixing for 10 minutes at 1.2 × 10 ⁴ rpm using a TK homomixer, the filtration operation was performed twice to obtain a filter cake. .

  The obtained filter cake was dried at 45 ° C. for 48 hours using a circulating dryer, and then classified using a mesh having an opening of 75 μm to obtain base particles.

  100 parts of the obtained base particles and 1 part of silica subjected to hydrophobic treatment with an average primary particle size of 13 nm were mixed using a Henschel mixer to obtain a toner.

[Example 2]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 2 was used instead of the vinyl resin dispersion 1.

[Example 3]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 3 and the amorphous polyester 2 were used instead of the vinyl resin dispersion 1 and the amorphous polyester 1, respectively.

[Example 4]
1013 parts of ion-exchanged water, 60 parts of vinyl resin dispersion 1, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyldiphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 2 was obtained.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 2 and the amorphous polyester 2 were used in place of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Example 5]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 4 was used instead of the vinyl resin dispersion 1.

[Example 6]
A toner was obtained in the same manner as in Example 1 except that Prepolymer 1 and Ketimine 1 were not used.

[Comparative Example 1]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 5 was used instead of the vinyl resin dispersion 1. At this time, the base particles did not have a core-shell structure.

[Comparative Example 2]
1013 parts of ion-exchanged water, 60 parts of vinyl resin dispersion 1, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyldiphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 2 was obtained.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 2 was used instead of the aqueous medium 1.

[Comparative Example 3]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 6 was used instead of the vinyl resin dispersion 1.

[Comparative Example 4]
A toner was obtained in the same manner as in Example 1 except that amorphous polyester 3 was used instead of amorphous polyester 1.

[Comparative Example 5]
1013 parts of ion exchange water, 110 parts of vinyl resin dispersion 1, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 3 was obtained.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 3 and the amorphous polyester 4 were used in place of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Comparative Example 6]
1013 parts of ion-exchanged water, 60 parts of vinyl resin dispersion 1, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyldiphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 2 was obtained.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 2 and the amorphous polyester 4 were used in place of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Comparative Example 7]
After mixing 850 parts of ion-exchanged water and 150 parts of crystalline polyester 2 and raising the temperature to 85 ° C., it is dispersed using a homogenizer, Ultra Tarax (manufactured by IKA Japan), and a dispersion of crystalline polyester 1 was obtained.

Disperser in which 80 parts of ion-exchanged water and 20 parts of amorphous polyester 5 are mixed, pH is adjusted to 8.5 using ammonia, and Cavitron CD1010 (manufactured by Eurotech) is remodeled into a high-temperature and high-pressure type. Was used to disperse the rotor at a rotational speed of 60 Hz, a pressure of 5 kgf / cm ² , and heating by a heat exchanger at 140 ° C. to obtain a dispersion 1 of amorphous polyester. Using a laser diffraction / scattering particle size distribution analyzer LA-920 (manufactured by Horiba, Ltd.), the volume average particle size of the dispersion 1 of amorphous polyester was measured and found to be 150 nm. Further, the dispersion 1 of amorphous polyester had a solid content concentration of 30% by mass.

  After mixing 250 parts of cyan pigment ECB-301 (manufactured by Dainichi Seika Co., Ltd.), 20 parts of anionic surfactant Neogen RK (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 730 parts of ion-exchanged water, Ultratarax (IKA) of a homogenizer From Japan) to obtain a dispersion 1 of a colorant.

  350 parts of paraffin wax having a melting point of 90 ° C., 15 parts of anionic surfactant Neogen RK (Daiichi Kogyo Seiyaku Co., Ltd.) and 635 parts of ion-exchanged water were mixed and heated to 90 ° C. Dispersion was performed using Lux (manufactured by IKA Japan) to obtain a release agent dispersion 1.

In a round stainless steel flask, 680 parts of crystalline polyester dispersion 1, 340 parts of amorphous polyester dispersion 1, glass transition point 61.7 ° C., weight average molecular weight 1.8 × 10 ³ A dispersion of a non-crystalline polyester having a number average molecular weight of 1.4 × 10 ³ Superester NS100H (manufactured by Arakawa Chemical Co., Ltd.) 120 parts, 52 parts of a colorant dispersion 1 and 66 parts of a release agent dispersion After the liquid 1 was added, 5 parts of calcium chloride (manufactured by Wako Pure Chemical Industries, Ltd.), 650 parts of ion-exchanged water, and 340 parts of an amorphous polyester dispersion 1 were added. Next, after heating up to 60 degreeC and hold | maintaining for 3 hours, when observing using an optical microscope, it was confirmed that the aggregated particle | grains whose volume average particle diameter is 5 micrometers are formed. Furthermore, after maintaining at 60 ° C. for 1 hour, observation using an optical microscope confirmed that aggregated particles having a volume average particle size of 5.5 μm were formed.

  Since the pH of the obtained dispersion of aggregated particles was 3.8, the pH was adjusted to 5.0 using a 0.5% by mass aqueous solution of sodium carbonate (manufactured by Wako Pure Chemical Industries, Ltd.). When the obtained aggregated particle dispersion was heated to 80 ° C. and held for 30 minutes and then observed using an optical microscope, it was confirmed that coalesced spherical particles were formed. Further, the temperature was lowered to 30 ° C. at a rate of 1 ° C./min while adding ion-exchanged water, followed by filtration. Next, after washing with 2000 parts of ion-exchanged water, filtration was performed to obtain a core dispersion 1. The core dispersion 1 had a solid content of 50% by mass.

  After putting 560 parts of core dispersion 1 in the flask, 100 parts of vinyl resin dispersion 7 was added, and then ion-exchanged water was added so that the solid concentration was 35% by mass. Next, after adjusting the pH to 3.0 using a 0.3 mol / L nitric acid aqueous solution, 0.28 parts of polyaluminum chloride is added, and the temperature is raised to 48 ° C. at a rate of 0.5 ° C./min. And held for 2 hours. Further, the temperature was raised to 57 ° C. at a rate of 0.1 ° C./min. Since pH was 7.3 at this time, after adjusting pH to 7.5 using 0.5 mol / L sodium hydroxide aqueous solution, it hold | maintained at 57 degreeC for 10 hours. Since it was confirmed that a shell was formed on the surface of the core using a scanning electron microscope, the temperature was lowered to 20 ° C. in 30 minutes. Next, it was filtered, washed with ion exchange water, and then dried using a vacuum dryer to obtain base particles.

  100 parts of the obtained base particles and 1 part of silica subjected to hydrophobic treatment with an average primary particle size of 13 nm were mixed using a Henschel mixer to obtain a toner.

[Example 7]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 8 was used instead of the vinyl resin dispersion 1.

[Example 8]
A toner was obtained in the same manner as in Example 1 except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 9]
A toner was obtained in the same manner as in Example 2 except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 10]
A toner was obtained in the same manner as in Example 3, except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 11]
A toner was obtained in the same manner as in Example 4 except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 12]
A toner was obtained in the same manner as in Example 5, except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 13]
A toner was obtained in the same manner as in Example 6 except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 14]
A toner was obtained in the same manner as in Example 7 except that 120 parts of amorphous polyester 3 was used instead of 120 parts of prepolymer 1 and 3.5 parts of ketimine 1.

[Example 15]
A toner was obtained in the same manner as in Example 1, except that the dispersion 1 of amorphous polyester was used instead of the dispersion 1 of vinyl resin.

[Example 16]
A toner was obtained in the same manner as in Example 1, except that the dispersion 2 of amorphous polyester was used instead of the dispersion 1 of vinyl resin.

[Example 17]
A toner was obtained in the same manner as in Example 1 except that the dispersion 3 of amorphous polyester was used instead of the dispersion 1 of vinyl resin.

[Example 18]
Mixing 1013 parts of ion-exchanged water, 60 parts of dispersion 1 of amorphous polyester, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyldiphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate The aqueous medium 4 was obtained by stirring.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 4 and the amorphous polyester 2 were used in place of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Example 19]
A toner was obtained in the same manner as in Example 1, except that the amorphous polyester dispersion 4 was used instead of the vinyl resin dispersion 1.

[Example 20]
A toner was obtained in the same manner as in Example 1 except that the prepolymer 1 and the ketimine 1 were not used, and the amorphous polyester dispersion 1 was used instead of the vinyl resin dispersion 1.

[Example 21]
A toner was obtained in the same manner as in Example 1 except that the amorphous polyester dispersion 5 was used instead of the vinyl resin dispersion 1.

[Example 22]
Mixing 1013 parts of ion exchange water, dispersion 2 of 70 parts of amorphous polyester, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate The aqueous medium 5 was obtained by stirring.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 5 and the amorphous polyester 2 were used in place of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Example 23]
Mixing 1013 parts of ion-exchanged water, 60 parts of amorphous polyester dispersion 4, 37 parts of a 48.3% by weight aqueous solution of dodecyl diphenyl ether disulfonate sodium Eleonol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate The aqueous medium 6 was obtained by stirring.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 6 and the amorphous polyester 2 were used instead of the aqueous medium 1 and the amorphous polyester 1, respectively.

[Comparative Example 8]
A toner was obtained in the same manner as in Example 1 except that the vinyl resin dispersion 8 and the amorphous polyester 3 were used in place of the vinyl resin dispersion 1 and the amorphous polyester 1, respectively.

[Comparative Example 9]
1013 parts of ion-exchanged water, 110 parts of vinyl resin dispersion 8, 37 parts of a 48.3% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate, Eleminol MON-7 (manufactured by Sanyo Chemical Industries) and 90 parts of ethyl acetate are mixed and stirred. Thus, an aqueous medium 7 was obtained.

  A toner was obtained in the same manner as in Example 1 except that the aqueous medium 7 was used instead of the aqueous medium 1.

[Comparative Example 10]
A toner was obtained in the same manner as in Comparative Example 9, except that the emulsified slurry 1 was placed in a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C. for 8 hours, followed by aging at 44 ° C. for 96 hours. It was.

[Comparative Example 11]
Instead of the vinyl resin dispersion 1, the vinyl resin dispersion 8 was used. The emulsified slurry 1 was placed in a container equipped with a stirrer and a thermometer, and the solvent was removed at 30 ° C for 8 hours. A toner was obtained in the same manner as in Example 1 except that aging was conducted for 96 hours.

  Tables 1 and 2 show the physical properties of the obtained toner.

トナーの物性の評価方法を以下に示す。

A method for evaluating the physical properties of the toner is shown below.

(Thermal hardness St, softening index Ct and thermal retention Ht)
Evaluation was performed using a flow tester CFT-500D (manufactured by Shimadzu Corporation). Specifically, first, 1 g of toner was pressure-molded into a cylindrical shape having a diameter of 1 cm to obtain a tableted toner T. Next, as shown in FIG. 4A, the tableted toner T placed in the cylinder C was preheated for 200 seconds and heated to T _s (50 ° C.). Further, while applying a constant load (2~25kgf) by the plunger P, by raising the temperature to the outlet end temperature _{T end} at 3 ° C. / min heating body H, outflow of toner T 'which is melted from a die D Then, as shown in FIG. 4 (b), the descending amount of the plunger P with respect to the temperature of the heating element H was measured. A die having a diameter of 0.5 mm and a length of 1.0 mm was used.

(Shell thickness)
After the toner was embedded in an epoxy resin and cured, the shell and the core were subjected to differential dyeing by gas exposure with ruthenium tetroxide for 5 minutes. Next, a section was cut out with a knife, and an ultrathin section of toner having a thickness of 200 nm was prepared using an ultramicrotome ULTRACUT UCT (manufactured by Leica). Furthermore, using a transmission electron microscope H7000 (manufactured by Hitachi High-Tech), an ultrathin section of the toner was observed at an acceleration voltage of 100 kV, and the thickness of the shell was measured.

(Average circularity)
The average circularity was measured using a flow particle image analyzer FPIA-2100 and analysis software FPIA-2100 Data Processing Program for FPIA version 00-10 (manufactured by Sysmex Corporation). Specifically, first, 0.1% to 0.5 ml of 10% by weight surfactant Neogen SC-A (Daiichi Kogyo Seiyaku Co., Ltd.) and 0.1 to 0.5 g of toner are added to a glass 100 ml beaker. After stirring with microspatel, 80 ml of ion exchange water was added. The average circularity was measured when the obtained dispersion was dispersed for 3 minutes using an ultrasonic disperser (manufactured by Honda Electronics Co., Ltd.) and the concentration was 5000 to 15000 / μl.

(Shape factors SF-1 and SF-2)
300 toner images photographed using a field emission scanning electron microscope S-4200 (manufactured by Hitachi, Ltd.) were randomly sampled, and the image information was sent to an image analyzer Luzex AP (Nireco) via an interface. And the shape factors SF-1 and SF-2 were calculated.

(Number average particle diameter Dn and weight average particle diameter D ₄ )
Using a Coulter Multisizer II (manufactured by Beckman Coulter, Inc.) to measure the number average particle diameter Dn and the weight average particle diameter D _4. Specifically, first, 0.1 to 5 ml of a surfactant polyoxyethylene alkyl ether was added to 100 to 150 ml of an electrolytic solution ISOTON-II (manufactured by Coulter). Next, 2 to 20 mg of toner was added and dispersed using an ultrasonic disperser for about 1 to 3 minutes. The number average particle diameter and the weight average particle diameter of the obtained sample dispersion were measured using a 100 μm aperture. In addition, as a channel, it is 2.00-2.52 micrometers; 2.52-3.17 micrometers; 3.17-4.00 micrometers; 4.00-5.04 micrometers; 5.04-6.35 micrometers; 6.35- 8.00 to 10.08 μm; 10.08 to 12.70 μm; 12.70 to 16.00 μm; 16.00 to 20.20 μm; 20.20 to 25.40 μm; 25.40 to 32. 00 μm; 13 channels of 32.00 to 40.30 μm were used, and particles having a particle size of 2.00 to 40.30 μm were measured.

[Creation of carrier]
450 parts of toluene, 450 parts of silicone resin SR2400 (made by Toray Dow Corning Silicone Co., Ltd.) with a solid content of 50% by mass, 10 parts of aminosilane SH6020 (made by Toray Dow Corning Silicone Co., Ltd.) and 10 parts of carbon black Was used for 10 minutes to prepare a coating solution for coating layer. The obtained coating solution for coating layer and 5000 parts of Mn ferrite having a weight average particle diameter of 35 μm are placed in a coating apparatus for applying a rotating bottom plate disk and a stirring blade in a fluidized bed to form a swirling flow, The coating layer coating solution was applied to Mn ferrite. Next, using an electric furnace, it was baked at 250 ° C. for 2 hours to obtain a carrier on which a coating layer having an average thickness of 0.5 μm was formed.

[Production of developer]
100 parts of the carrier and 7 parts of the toner were uniformly mixed and charged using a type of tumbler mixer in which the container was rolled and stirred to obtain a developer.

[Developer Evaluation 1]
The developer was evaluated using a remodeling machine in which the fixing unit of imgio MP C6000 (manufactured by Ricoh) was remodeled. Specifically, the system speed was adjusted to 0.35 m / s. The fixing unit of the fixing unit was adjusted so as to press the recording paper on which the toner image was transferred at a surface pressure of 4 × 10 ⁵ Pa for 0.04 seconds. In addition, as a fixing roll, after apply | coating the tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA) to the surface, it shape | molded and used what adjusted the surface. The heating temperature of the fixing roll was set to 140 ° C.

  Tables 3 and 4 show the evaluation results of the developer.

現像剤の評価方法を以下に示す。

The developer evaluation method is shown below.

(Low temperature fixability in high temperature and high humidity environment)
Low temperature fixability can be achieved by forming images by changing the temperature of the fixing roll by 5 ° C. after outputting 10,000 sheets of a chart with an image area ratio of 3% continuously in an environment of 45 ° C. and 80% RH. evaluated. Specifically, after forming an image on full-color PPC paper type 6200 (manufactured by Ricoh) so that the image density measured using X-Rite 938 (manufactured by X-Rite) is 1.2, The temperature at which the image density after rubbing 50 times using a clock meter equipped with a sand eraser becomes 70% or more of the image density before rubbing was defined as the minimum fixing temperature. Compared with imagio MP C6000 (manufactured by Ricoh Co., Ltd.), the case where the fixing lower limit temperature is 15 ° C. or more is low, ◯ is 5 ° C. or more and less than 15 ° C., ○ is 0 ° C. or more and less than 5 ° C., and Δ is high. The case was determined as x.

(Spent resistance in high temperature and high humidity environment)
After outputting 100,000 sheets of an image area ratio of 20% in an environment of 45 ° C. and 80% RH, the developer is taken out and placed in a cylindrical cage with metal meshes at both ends, and the developer is developed with high-pressure air. The toner was removed from the toner and only the carrier was collected. After embedding the carrier in a resin, a cross section of the carrier is prepared using a cross section polisher IB-09010CP (manufactured by JEOL Ltd.) and observed using a field emission scanning electron microscope ULTRA55 (manufactured by Zeiss Corp.). Thus, spent resistance was evaluated. Specifically, ten carriers were selected at random, and the spent thickness was analyzed using image processing software. The case where no spent was observed was evaluated as ◎, the case where the average value of spent was less than 100 nm was evaluated as ◯, the case where it was 100 nm or more and less than 200 nm was evaluated as Δ, and the case where it was 200 nm or more was determined as ×.

(Hot offset resistance in high temperature and high humidity environment)
After outputting 10,000 sheets of a chart with an image area ratio of 3% under an environment of 45 ° C. and 80% RH, the temperature of the fixing roll is changed by 5 ° C. to form an image, thereby preventing hot offset resistance. evaluated. Specifically, after forming an image on full-color PPC paper type 6200 (manufactured by Ricoh) so that the image density measured using X-Rite 938 (manufactured by X-Rite) is 1.2, The image was visually evaluated to evaluate the hot offset, that is, the temperature at which image smearing due to toner adhering to the fixing unit occurs. In addition, as compared with imagio MP C6000 (manufactured by Ricoh Co., Ltd.), the case where the temperature at which hot offset occurs was 5 ° C. or higher was evaluated as “◯”, the case where 0 ° C. or more and less than 5 ° C. was high as “Δ”, and the case where it was low as “X”.

[Developer Evaluation 2]
The developer was evaluated using a remodeling machine in which the fixing unit of imgio MP C6000 (manufactured by Ricoh) was remodeled. Specifically, the system speed was adjusted to 2.2 m / s. The fixing unit of the fixing unit was adjusted so that the recording paper on which the toner image was transferred was pressed at a surface pressure of 1.1 × 10 ⁶ Pa for 0.13 seconds. In addition, as a fixing roll, after apply | coating the tetrafluoroethylene perfluoroalkyl vinyl ether copolymer (PFA) to the surface, it shape | molded and used what adjusted the surface. The heating temperature of the fixing roll was set to 150 ° C.

  Table 5 shows the evaluation results of the developer.

DESCRIPTION OF SYMBOLS 10 Photosensitive drum 20 Charging roller 24 Transfer belt 25 Fixing apparatus 30 Exposure apparatus 40 Developing apparatus 50 Intermediate transfer belt 60 Cleaning apparatus 70 Static elimination lamp 80 Transfer roller 100 Image forming apparatus

JP 2006-267231 A

Claims (9)

Having base particles having a core-shell structure comprising a core containing crystalline polyester, amorphous polyester, colorant and release agent, and a shell containing resin;
The thermal hardness is 0.5 or more and 1.8 or less,
The softening index is 80 ° C. or higher and 95 ° C. or lower,
A toner having a thermal retention of 30 ° C. or more and 50 ° C. or less.   The toner according to claim 1, wherein the resin is a vinyl resin or polyester.   The toner according to claim 1, wherein the shell has a thickness of 0.01 μm to 2 μm.   The toner according to claim 1, wherein the core further contains a urea-modified polyester. The toner according to any one of claims 1 to 4, wherein the average circularity is 0.93 to 0.99. The shape factor SF-1 is 100 or more and 150 or less,
The toner according to any one of claims 1 to 5 , wherein the shape factor SF-2 is 100 or more and 140 or less. The weight average particle size is 2 μm or more and 7 μm or less,
The toner according to any one of claims 1 to 6 ratio of the weight average particle diameter to number average particle diameter, characterized in that 1.00 to 1.25. Developer, comprising a toner and a carrier according to any one of claims 1 to 7. A method of forming a full-color image using a tandem image forming apparatus,
Forming electrostatic latent images on a plurality of electrostatic latent image carriers;
Developing the electrostatic latent images formed on the plurality of electrostatic latent image carriers using the developer according to claim 8 to form a toner image;
A step of sequentially transferring the toner images formed on the plurality of electrostatic latent image carriers to an intermediate transfer member to form a full color toner image;
Transferring the full color toner image transferred to the intermediate transfer member to a recording medium;
There is a step of fixing the full-color toner image transferred to the recording medium by applying pressure to the surface pressure of 1 × 10 ⁵ Pa to 3 × 10 ⁷ Pa for 0.03 seconds to 0.4 seconds and heating. And
An image forming method, wherein the system speed is 0.2 m / s or more and 3 m / s or less.

Images