JP6143251B2 - Toner for developing electrostatic image and method for producing the toner - Google Patents

Description

  The present invention relates to an electrostatic image developing toner used in an electrophotographic apparatus, an electrostatic recording apparatus, and the like, and a method for producing the toner.

  Conventionally, in an electrophotographic apparatus, an electrostatic recording apparatus or the like, an electrical or magnetic latent image is visualized with toner. For example, in electrophotography, an electrostatic image (latent image) is formed on a photoconductor, and then the latent image is developed using toner to form a toner image. The toner image is usually transferred onto a transfer material such as paper and then fixed by a method such as heating.

  Toner used for electrostatic image development is generally colored particles in which a binder, a colorant, a charge control agent, and other additives are contained in a binder resin. There is a suspension polymerization method. In the pulverization method, a colorant, a charge control agent, an anti-offset agent, etc. are melt-mixed in a thermoplastic resin and uniformly dispersed, and the resulting toner composition is pulverized and classified to produce a toner. doing. According to the pulverization method, a toner having some excellent characteristics can be produced, but there is a limit to the selection of the toner material. For example, a toner composition obtained by melt mixing must be capable of being pulverized and classified by an economically usable apparatus. From this demand, the melt-mixed toner composition must be sufficiently brittle. For this reason, when the toner composition is actually pulverized into particles, a high-range particle size distribution is likely to be formed, and when attempting to obtain a copy image with good resolution and gradation, for example, the particle size There is a problem that the fine powder of 5 μm or less and the coarse powder of 20 μm or more must be removed by classification, resulting in a very low yield. Furthermore, in the pulverization method, it is difficult to uniformly disperse the colorant, the charge control agent and the like in the thermoplastic resin. Such non-uniform dispersion of the compounding agent adversely affects the fluidity, developability, durability, image quality, and the like of the toner.

  On the other hand, for example, in Patent Document 1 (Japanese Patent No. 3344214) and Patent Document 2 (Japanese Patent No. 3455523), a resin solution prepared by dissolving a resin prepared in advance by a polymerization reaction is used as a surfactant or a water-soluble resin. A method of obtaining toner particles by dispersing in an aqueous medium in the presence of a dispersion stabilizer such as inorganic fine particles or resin fine particles, and removing the solvent by heating, decompression, etc. (dissolved resin suspension method) ) Has been proposed. According to these proposed methods, uniform particles can be obtained without requiring a classification step.

  By the way, as for the binder resin occupying 70% or more of the constituent components of the toner, conventionally, a thermoplastic resin derived from petroleum such as styrene / acrylic resin or polyester resin has been used. However, in recent years, due to environmental considerations, attention has been focused on methods that use biomass-derived biodegradable resins made from renewable resources as binder resins for toners, which have little impact on the environment when discarded. A method has been proposed.

  As a means for this, there is an example of using a biodegradable microbial-produced aliphatic polyester as a binder resin (for example, Patent Document 3 (Japanese Patent Laid-Open No. 4-179967)). The polyester is used as a resin for toner. In this case, since the softening temperature of the toner is high, the fixing temperature must be set high, which is not suitable from the viewpoint of energy saving. As a method for lowering the fixing temperature, a method of reducing the softening temperature by adding a large amount of plant-based wax to the biodegradable resin (for example, Patent Document 4 (Patent No. 2597452)) has been proposed. Even if it is possible to lower the softening temperature of the toner, the toner tends to aggregate due to the wax component, resulting in poor productivity and poor toner transportability in the developing machine due to poor toner fluidity. Problems occur.

  Further, in order to obtain low-temperature fixability and fixing stability, a method using two types of resins having different softening points and a binder resin containing a biodegradable resin (for example, Japanese Patent Application Laid-Open No. 2006-91278). Patent Document 6 (Japanese Patent Laid-Open No. 2006-285150) is also presented. In these methods, a resin having a low softening point serves as a bridge between a resin having a high softening point and a biodegradable resin, and the biodegradable resin is uniformly dispersed in the binder resin. However, if the blending ratio of the biodegradable resin is set high, the biodegradable resin may be poorly dispersed, resulting in a decrease in developability due to variations in charging performance, and the durability deteriorates. The compounding ratio in the resin is as low as about 20% by mass.

Further, in Patent Document 7 (Japanese Patent Application Laid-Open No. 2010-14757), as a polylactic acid toner excellent in thermal characteristics, heat-resistant storage stability, and transparency, a resin comprising a reaction product of polylactic acid and polylactic acid with an extender. A method for forming a film on the particles with other resin fine particles has been proposed. This method is useful in terms of heat-resistant storage stability and transparency of the toner, but there is a problem that the effect of lowering the fixing temperature is insufficient and it is unsuitable from the viewpoint of energy saving.
As described above, there are many problems in using biodegradable resin as the main resin component of toner binder resin, and even when part of binder resin is replaced with biodegradable resin, the amount of the compound is limited. Therefore, more biodegradable resins are expected to be blended while maintaining the properties as a binder resin.

An object of the present invention is to solve various problems in the prior art and achieve the following objects.
That is, an object of the present invention is to provide a toner formed from a plant-derived raw material having a small particle size and a narrow particle size distribution, which has both low-temperature fixability and heat-resistant storage stability, and can obtain high image quality even in long-term use. To do.

  The inventors have completed the present invention to solve the above-described problems. That is, according to the present invention, a toner formed from a plant-derived raw material having a small particle size and a narrow particle size distribution that achieves both the following low-temperature fixability and heat-resistant storage stability and can obtain high image quality even in long-term use. Can be provided.

That is, the toner of the present invention is
An electrostatic charge image developing toner comprising toner particles containing a binder resin and a colorant, wherein the binder resin comprises an amorphous polyester having a glass transition point of -20 ° C or higher and 35 ° C or lower, poly L-lactic acid, And a poly L-lactic acid content of 50% by mass to 80% by mass of the total binder resin, and poly L-lactic acid as a crystallization nucleating agent for poly L-lactic acid in the toner particles. A toner for developing an electrostatic image, comprising a crystalline resin of the optical isomer (D-form) and / or an organic compound containing the structure of the optical isomer (D-form) of poly L-lactic acid.

  According to the present invention, it is possible to provide a toner that is compatible with low-temperature fixability and heat-resistant storage stability, has a small particle size and a narrow particle size distribution, and is formed from plant-derived raw materials.

3 is a cross-sectional observation photograph of toner in a fixed image.

  A mode for carrying out the present invention will be described. Note that it is easy for a person skilled in the art to make other embodiments by appropriately changing or correcting the following aspects of the present invention, and these changes and modifications are included in the present invention. The description is an example of a preferred embodiment of the invention and is not intended to limit the invention.

As described above, the toner of the present invention is an electrostatic charge image developing toner including toner particles containing a binder resin and a colorant, and the binder resin has a glass transition point of −20 ° C. or more and 35 ° C. or less. A copolymer of non-crystalline polyester and poly L-lactic acid, and the content of poly L-lactic acid is 50% by mass or more and 80% by mass or less of the total binder resin. As a crystallization nucleating agent for lactic acid, it contains a crystalline resin of an optical isomer (D-form) of poly L-lactic acid and / or an organic compound containing a structure of an optical isomer (D-form) of poly L-lactic acid.
The toner particles include a binder resin containing at least a copolymer of the non-crystalline polyester and poly-L-lactic acid, a colorant, and a crystallization nucleating agent for the poly-L-lactic acid in an organic solvent. It is obtained by dissolving or dispersing the contained toner material, emulsifying or dispersing an oil phase comprising the dissolved or dispersed toner material in an aqueous medium, and removing the organic solvent from the dispersion obtained by granulation. It is preferable.
The toner material is not particularly limited as long as it can form a toner except that it contains a binder resin containing a copolymer of the non-crystalline polyester and poly-L-lactic acid, a colorant, and a crystallization nucleating agent. However, it can be appropriately selected according to the purpose, and for example, if necessary, it further comprises other components such as a release agent, a charge control agent, and resin fine particles.

(Binder resin)
The binder resin contains a copolymer of amorphous polyester and poly L-lactic acid.
It is important that the content of the poly L-lactic acid is 50% by mass or more and 80% by mass or less of the total binder resin. By setting the content of poly L-lactic acid within the above range, particle deformation can be suppressed by crystallization of poly L-lactic acid, and the effects of the present invention can be obtained.
Monomer used for polymerization reaction of poly-L-lactic acid is optical purity X (%) = | X (L form) -X (D form) | in terms of monomer component | The L-form ratio (mol%) and X (D-form) in the formula represent the D-form ratio (mol%) in terms of an optically active monomer] is 90% or more and 100% or less, and 95% to 100%. Is preferred.
In the toner comprising the plant-derived raw material obtained according to the present invention, it is important to develop heat-resistant storage stability by suppressing particle deformation by crystallization of polylactic acid. That is, the amorphous polyester has a glass transition point in the ultra-low temperature to room temperature range of −20 ° C. or more and 35 ° C. or less. By including this in the binder resin, the softening point as the toner base particles is on the low temperature side. Although it is shifted, blocking resistance (sometimes referred to as “preservability”) and low-temperature fixability are not easily deformed by crystallizing a poly L-lactic acid part having a melting point of 100 ° C. or higher and 200 ° C. or lower. It is possible to achieve both. When the optical purity of the poly L-lactic acid part is 90% or more, the crystallinity increases and the effect of improving the heat-resistant storage stability of the toner is enhanced. As a polymerization method of poly L-lactic acid, it can be obtained by polymerization according to a known method appropriately selected according to the purpose, but it is synthesized by ring-opening polymerization of cyclic lactide in which the molecular weight, the residual monomer amount and the like are easily controlled. It is preferable to do.

  The weight average molecular weight of the poly L-lactic acid part is preferably 10,000 or more and 50,000 or less. When the weight average molecular weight is lower than 10,000, the content of residual monomers and oligomers is large, and the toner has sufficient heat-resistant storage stability due to the decrease in crystallinity of the copolymer and the generation of decomposition products of the residual monomers. It may not be obtained. When the weight average molecular weight is higher than 50000, the melt viscosity of the copolymer is too high, which may inhibit the low-temperature fixability.

  The component to be copolymerized with the poly-L-lactic acid is a non-crystalline polyester that has sufficient flexibility even when the molecular weight is lowered in that it can be melted sharply during fixing and the surface of the image can be smoothed. Is important, and other resins may be used in combination with polyester. In the toner of the present invention, poly L-lactic acid and non-crystalline polyester are copolymerized, so that there is an effect of dissolving poly L-lactic acid which is not normally dissolved in a general organic solvent. That is, it is important that the polyester copolymerized with poly L-lactic acid has no crystallinity.

The presence or absence of crystallinity of the resin is determined by DSC measurement and the presence or absence of an endothermic peak due to heat of fusion. That is, the case where there is no endothermic peak is regarded as non-crystalline.
<DSC measurement of non-crystalline polyester>
The presence or absence of endothermic peaks due to the heat of fusion of the amorphous polyester and each material in the present invention, and the glass transition point are measured using, for example, a DSC system (differential scanning calorimeter) (“DSC-60”, manufactured by Shimadzu Corporation). can do.
Measurement conditions Sample container: Aluminum sample pan (with lid)
Sample amount: 5mg
Reference: Aluminum sample pan (alumina 10mg)
Atmosphere: Nitrogen (flow rate 50 ml / min)
Temperature conditions Starting temperature: 20 ° C
Temperature increase rate: 10 ° C / min
End temperature: 150 ° C
Holding time: None Temperature drop: 10 ° C / min
End temperature: -20 ° C
Holding time: None Temperature increase rate: 10 ° C / min
End temperature: 150 ° C

  The glass transition temperature of the non-crystalline polyester resin is −20 ° C. or higher and 35 ° C. or lower, preferably 15 ° C. or higher and 30 ° C. or lower. If the glass transition temperature is lower than -20 ° C, sufficient heat-resistant storage stability in the storage temperature range of the toner cannot be obtained, and aggregation of toner particles occurs. When the temperature is higher than 35 ° C., heat-resistant storage stability can be exhibited, but the low-temperature fixability of the toner may be inhibited.

The amorphous polyester resin used in the present invention is one or two or more polyols represented by the following general formula (1):
A- (OH) m (1)
[Wherein, A represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. m represents an integer of 2 to 4. ]
What polyesterified with 1 type, or 2 or more types of polycarboxylic acid represented by following General formula (2) is preferable.
B- (COOH) n (2)
[Wherein, B represents an alkyl group having 1 to 20 carbon atoms, an alkylene group, or an aromatic group or heterocyclic aromatic group which may have a substituent. n represents an integer of 2 to 4. ]

  Specific polyols represented by the general formula (1) include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, sorbitol, 1,2, 3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4-butanetriol, 1,2,5-pentanetriol, glycerol, 2-methyl Propanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5-trihydroxymethylbenzene, bisphenol A, bisphenol A ethylene oxide adduct, bisphenol A propylene oxide addition Products, hydrogenated bisphenol A, hydrogenated bisphenol A ethylene oxide adduct, hydrogenated bisphenol A propylene oxide adduct, and the like.

  Specific polycarboxylic acids represented by the general formula (2) include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, succinic acid, adipic acid, sebacic acid Azelaic acid, malonic acid, n-dodecenyl succinic acid, isooctyl succinic acid, isododecenyl succinic acid, n-dodecyl succinic acid, isododecyl succinic acid, n-octenyl succinic acid, n-octyl succinic acid, isooctenyl succinic acid, Isooctyl succinic acid, 1,2,4-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4-naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5 -Hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxyprop 1,2,4-cyclohexanetricarboxylic acid, tetra (methylenecarboxyl) methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, emporic trimer acid, cyclohexanedicarboxylic acid, cyclohexenedicarboxylic acid, Examples include butanetetracarboxylic acid, diphenylsulfonetetracarboxylic acid, and ethylene glycol bis (trimellitic acid).

As a copolymerization method of the copolymer of poly L-lactic acid and non-crystalline polyester, it can obtain by polymerizing in accordance with the well-known method suitably selected according to the objective, For example, the following methods are mentioned suitably.
(1) Melt non-crystalline polyester resin prepared in advance by polymerization reaction with poly L-lactic acid prepared in advance by polymerization reaction (any polymerization reaction mode such as ring-opening polymerization of lactide or dehydration condensation of lactic acid). A method of kneading and adjusting by transesterification under reduced pressure.
(2) Poly L-lactic acid prepared in advance by a polymerization reaction (which may be any polymerization reaction mode such as ring-opening polymerization of lactide or dehydration condensation of lactic acid) and an amorphous polyester resin prepared in advance by a polymerization reaction are suitable. A method of copolymerization by dissolving or dispersing in an appropriate solvent and reacting with an extender having two or more functional groups capable of reacting with hydroxyl groups or carboxylic acids at the ends of polymer chains such as isocyanate groups and epoxy groups.
(3) A method of polymerizing and copolymerizing poly-L-lactic acid from a polymer chain terminal of a polyester resin using a hydroxyl group of an amorphous polyester resin previously prepared by a polymerization reaction as a polymerization initiation component.
Regarding the completion of the copolymerization, the copolymer prepared in a solvent in which poly-L-lactic acid is not normally dissolved (for example, ethyl acetate, toluene, etc.) is dissolved at a mass ratio of 50%, and a precipitate is visually observed. If not, it is judged that the copolymerization is complete.

The binder resin contains a copolymer of an amorphous polyester having a glass transition point of −20 ° C. or more and 35 ° C. or less and poly L-lactic acid, and the content of poly L-lactic acid is the total binder resin. If it is 50 mass% or more and 80 mass% or less, there will be no restriction | limiting in particular, The copolymer of non-crystalline polyester and poly L-lactic acid may be used individually, and 2 or more types may be used together.
When two or more types are used in combination, a known binder resin can be appropriately selected according to the purpose. For example, polyester resin, silicone resin, styrene / acryl resin, styrene resin, acrylic resin, Examples include epoxy resins, diene resins, phenol resins, terpene resins, coumarin resins, amidoimide resins, butyral resins, urethane resins, ethylene / vinyl acetate resins, and polyester resins are preferred. There is no restriction | limiting in particular as said polyester resin, Although it can select suitably according to the objective, A urea modified polyester resin etc. are especially preferable.

The content of the binder resin in the toner is preferably 50% by mass or more and 90% by mass or less, and more preferably 60% by mass or more and 80% by mass or less. When the content of the binder resin in the toner is 50% by mass or less, the fixed image cannot secure sufficient adhesiveness, and the toner may peel from the paper. When the amount is more than 90% by mass, the content of toner materials other than the binder resin such as a colorant and a release agent is relatively reduced, so that basic functions as a toner such as coloring degree and offset resistance are exhibited. There are things that cannot be done.
In the present invention, the crystallization nucleating agent may be a resin, but is not included in the binder resin. Further, the crystalline polyester used as a fixing aid described later is not included in the binder resin.

  The binder resin here refers to a member that forms an image by holding the colorant on the paper surface by adhering to the paper when the toner is fixed on the paper to form an image. The crystalline polyester used as a fixing aid is compatible with the binder resin when the toner is heat-fixed and exhibits the effect of lowering the fixing temperature by reducing the viscoelasticity of the toner during heat-fixing. In itself or in the fixed image, the crystalline polyester resin is crystallized and separated from the binder resin. In particular, on the fixed image, it can be confirmed from the cross-sectional observation of the fixed image that the crystalline polyester resin is crystallized without including the colorant (FIG. 1). From the above, the crystalline polyester does not have a function as a binder resin for bonding paper and a colorant. Therefore, in this case, the crystalline polyester resin is not included in the binder resin.

The urea-modified polyester resin comprises an amine (B) as the active hydrogen group-containing compound and an isocyanate group-containing polyester prepolymer (A) as a polymer that can react with the active hydrogen group-containing compound. It is obtained by reacting in a medium.
The urea-modified polyester resin may contain a urethane bond in addition to the urea bond, and in this case, the molar ratio of the urea bond to the urethane bond (urea bond / urethane bond) is particularly limited. However, 100/0 to 10/90 is preferable, 80/20 to 20/80 is more preferable, and 60/40 to 30/70 is particularly preferable.
When the urea bond is less than 10, the hot offset resistance may be deteriorated.

Preferable specific examples of the urea-modified polyester resin include the following.
(1) Polyester prepolymer obtained by reacting a polycondensate of bisphenol A ethylene oxide 2-mole adduct and isophthalic acid with isophorone diisocyanate and urealated with isophorone diamine (2) Bisphenol A ethylene oxide 2-mole adduct and isophthalic acid A polyester prepolymer obtained by reacting a polycondensate of the above with isophorone diisocyanate and uread with isophorone diamine. (3) Bisphenol A ethylene oxide 2 mol adduct / bisphenol A propylene oxide 2 mol adduct and terephthalic acid polycondensate Polyester prepolymer reacted with isophorone diisocyanate and uread with isophoronediamine (4) Bisphenol A ethylene oxide 2-mol adduct / bisphenol A propylene Polyester prepolymer obtained by reacting polycondensate of 2-oxide adduct with terephthalic acid with isophorone diisocyanate and uread with isophoronediamine (5) Polycondensate of bisphenol A ethylene oxide 2-mol adduct and terephthalic acid Polyester prepolymer reacted with isophorone diisocyanate and uread with hexamethylenediamine (6) Polyester prepolymer obtained by reacting polycondensate of bisphenol A ethylene oxide 2 mol adduct and terephthalic acid with isophorone diisocyanate (7) Polyester prepolymer obtained by reacting polycondensate of bisphenol A ethylene oxide 2 mol adduct and terephthalic acid with isophorone diisocyanate (8) Polyester prepolymer obtained by reacting 2-condensate of bisphenol A ethylene oxide and polycondensate of isophthalic acid with diphenylmethane diisocyanate and ureating with hexamethylenediamine (9) Bisphenol A ethylene oxide Polyester prepolymer obtained by reacting 2 mol adduct / bisphenol A propylene oxide 2 mol adduct and terephthalic acid / dodecenyl succinic anhydride polycondensate with diphenylmethane diisocyanate, and uread with hexamethylenediamine (10) Bisphenol A ethylene Polyester prepolymer obtained by reacting a polycondensate of oxide 2 mol adduct and isophthalic acid with toluene diisocyanate is ureaated with hexamethylenediamine. What

  The urea-modified polyester resin is, for example, a solution or dispersion of a toner material containing a polymer (for example, an isocyanate group-containing polyester prepolymer (A)) that can react with an active hydrogen group-containing compound. It may be produced by emulsifying or dispersing in an aqueous medium together with a compound (for example, amines (B)), forming oil droplets, and subjecting both to an extension reaction or a crosslinking reaction in the aqueous medium. ) A toner material solution or dispersion is emulsified or dispersed in an aqueous medium to which an active hydrogen group-containing compound has been added in advance, oil droplets are formed, and the two are extended or cross-linked in the aqueous medium. You may let them. Alternatively, (3) after dissolving and dispersing the toner material in an aqueous medium, the active hydrogen group-containing compound is added to form oil droplets, and both extend from the particle interface in the aqueous medium. It may be generated by a reaction or a crosslinking reaction. In the case of (3), the modified polyester resin is preferentially produced on the surface of the toner to be produced, and it becomes possible to provide a concentration gradient on the toner particles.

  The reaction conditions for producing the adhesive substrate by emulsification or dispersion are not particularly limited, and are appropriately selected depending on the combination of the polymer capable of reacting with the active hydrogen group-containing compound and the active hydrogen group-containing compound. can do. In addition, as reaction time, 10 minutes-40 hours are preferable, and 2 hours-24 hours are more preferable.

  The weight average molecular weight (Mw) of the adhesive substrate is not particularly limited and may be appropriately selected depending on the intended purpose. Molecular weight distribution by GPC (gel permeation chromatography) soluble in tetrahydrofuran (THF) Is preferably 3,000 or more, more preferably 5,000 to 1,000,000, and particularly preferably 7,000 to 500,000. When the weight average molecular weight is less than 3,000, the hot offset resistance may be deteriorated.

The amines (B) are not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include diamine (B1), trivalent or higher polyamine (B2), amino alcohol (B3), and amino mercaptan. (B4), amino acid (B5), and those obtained by blocking the amino groups of B1 to B5 (B6).
These may be used individually by 1 type and may use 2 or more types together. Among these, diamine (B1) alone or a mixture of diamine (B1) and a small amount of trivalent or higher polyamine (B2) is particularly preferable.

Examples of the diamine (B1) include aromatic diamines, alicyclic diamines, and aliphatic diamines. Examples of the aromatic diamine include phenylenediamine, diethyltoluenediamine, 4,4′diaminodiphenylmethane, and the like. Examples of the alicyclic diamine include 4,4′-diamino-3,3′dimethyldicyclohexylmethane, diaminecyclohexane, and isophoronediamine. Examples of the aliphatic diamine include ethylene diamine, tetramethylene diamine, and hexamethylene diamine.
Examples of the trivalent or higher polyamine (B2) include diethylenetriamine and triethylenetetramine.
Examples of the amino alcohol (B3) include ethanolamine and hydroxyethylaniline.
Examples of the amino mercaptan (B4) include aminoethyl mercaptan and aminopropyl mercaptan.
Examples of the amino acid (B5) include aminopropionic acid and aminocaproic acid.
Examples of the blocked B1-B5 amino group (B6) include, for example, ketimine compounds and oxazolidone compounds obtained from any of the amines of B1-B5 and ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.) Etc.

  It is important that the binder resin is incompatible with the cross-linked resin fine particles that coat the toner surface described later. In particular, the polyester resin has a cross-linked resin fine particle that is a styrene polymer, an acrylate polymer, or a methacrylic acid ester. In the case of fine particles of a crosslinked resin containing a polymer, there is almost no compatibility. In the emulsification step, when the crosslinked resin fine particles are added before or after the emulsification, the organic solvent is present in the droplets of the toner material, so the crosslinked resin fine particles may dissolve after adhering to the droplet surface. When the resin component constituting the toner is a polyester resin and the cross-linked resin fine particles are fine particles of a cross-linked resin containing a styrene polymer, an acrylate polymer, or a methacrylic ester polymer, the compatibility between the resins is poor. The crosslinked resin fine particles are present in a state of adhering without being incompatible with the droplets of the toner material. Accordingly, it is possible to realize a desirable form in which the toner enters to some extent from the surface of the droplet, is attached and fixed to the toner surface after the organic solvent is removed, and coats the toner particles.

  If the binder resin is dissolved at a mass ratio of 50% with respect to the organic solvent and the crosslinked resin fine particles are added to the solution, it is incompatible and separated. If not, it is judged visually that it is compatible.

(Crystal nucleating agent)
As the crystallization nucleating agent used in the present invention, an organic compound containing a poly (L-lactic acid) optical isomer (D-form) crystalline resin and / or a poly-L-lactic acid optical isomer (D-form) structure is used. Organic substances containing poly L-lactic acid optical isomer (D-form) structures that contain poly D-lactic acid with low molecular weight and cannot be called resins, and other types of polymers include The part whose part is poly D-lactic acid is mentioned. Although it will not specifically limit if it is an optical isomer (D form) of poly L-lactic acid, Preferably poly D-lactic acid and / or its copolymer are mentioned. The addition amount of the crystallization nucleating agent is not particularly limited, but is preferably 1 to 15 parts by mass, more preferably 2 to 12 parts by mass, and particularly preferably 3 to 10 parts by mass with respect to 100 parts by mass of poly L-lactic acid. When the amount is less than 1 part by mass, a remarkable crystallization promoting effect tends to be hardly obtained, and when the amount exceeds 15 parts by mass, the resin strength tends to decrease.
The poly-D-lactic acid copolymer is not particularly limited as long as it can be copolymerized with poly-D-lactic acid, but is not limited to the copolymer of non-crystalline polyester as a binder resin and poly-L-lactic acid. Those having solubility are preferable, and a copolymer with a polyester resin is particularly preferable. As the copolymerization method, it can be obtained by polymerization according to a known method appropriately selected according to the purpose, and the same method as the polymerization method of the copolymer of poly L-lactic acid and amorphous polyester can be selected.

  Organic crystallization other than the crystallization nucleating agent containing the crystalline resin of the optical isomer (D form) of poly L-lactic acid and / or the organic compound containing the structure of the optical isomer (D form) of poly L-lactic acid Examples of the nucleating agent include aliphatic esters, aliphatic amides, fatty acid metal salts, and the like. In the step of forming toner materials such as a binder resin dissolved or dispersed in an organic solvent as toner particles in an aqueous medium, organic crystals are used. Since the nucleating agent is eluted in the aqueous medium, it cannot be incorporated into the toner particles as intended, and the heat storage stability is not sufficiently improved due to the promotion of crystallization. Furthermore, examples of the inorganic crystallization nucleating agent include silicates such as talc, smectite, bentonite, dolomite, sericite, feldspar powder, kaolin, mica, and montmorillonite. Although they do not elute into an aqueous medium like the above-mentioned organic crystallization nucleating agent, they may inhibit the low-temperature fixability of the toner because they exist as fillers in the toner particles.

(Crosslinked resin fine particles)
The toner particles of the present invention are coated with fine particles of a crosslinked resin containing a styrene polymer, an acrylate polymer, or a methacrylic ester polymer, and the glass transition temperature of the fine particles of the crosslinked resin is 50 to 100 ° C. Is preferably 10 to 500 nm.
It is preferable that at least a crosslinked resin fine particle having a particle size of 10 to 500 nm is attached and solidified on the surface of the toner, and the toner particle is preferably coated with the crosslinked resin particle. It is preferable that As a result, the non-electrostatic adhesion force of the toner particles can be reduced by the spacer effect, and even when the mechanical stress with the passage of time is large as in a high-speed machine, the static particles are buried by the surface of the toner. It is possible to suppress an increase in the electric adhesion force, and it is possible to maintain a sufficient transfer efficiency over a long period. In particular, the toner of the present invention is very effective when the intermediate transfer system has a primary transfer process, a secondary transfer process, and two transfer processes. The effect can be exerted particularly greatly in a relatively high-speed image forming process (transfer linear speed of 300 to 1000 mm / sec, transfer time at the secondary nip portion of 0.5 to 20 msec). In a process with a lower linear speed or shorter secondary transfer time than this, the difference between the present invention and a toner in which the crosslinked resin fine particles are not arranged on the surface is not large. Further, when the speed is higher than this, the transfer efficiency tends to be prevented from being lowered.

  When the particle diameter of the crosslinked resin fine particles is smaller than 10 nm, the spacer effect cannot be sufficiently obtained, so that the non-electrostatic adhesion force of the toner particles cannot be reduced. When the mechanical stress is large, the crosslinked resin fine particles and the external additive are easily buried in the toner surface, and there is a possibility that sufficient transfer efficiency cannot be maintained for a long time. Further, when the particle diameter of the crosslinked resin fine particles is larger than 500 nm, the fluidity of the toner is deteriorated and the uniform transferability may be hindered.

The “particle size” of the crosslinked resin fine particles is a “volume average particle size” and can be measured as follows.
<Measurement of volume average particle diameter of crosslinked resin fine particles>
The volume average particle diameter of the crosslinked resin fine particles is measured using “LA-920” (manufactured by Horiba, Ltd.). When measuring LA-920, analysis is performed using an application dedicated to LA-920 (Ver3.32) (manufactured by Horiba Ltd.). Specifically, LA-920 was measured by measuring the background with the solvent used for the crosslinked resin fine particles, adjusting the optical axis, and then dropping the crosslinked resin fine particle dispersion to obtain a LA-920 transmittance value of 70 to 70. The volume average particle diameter is measured under the condition of 95%. It is important for this measuring apparatus to measure under the condition that the transmittance value of LA-920 is in the range of 70 to 95% from the viewpoint of measurement reproducibility of the particle diameter. In order to obtain the transmittance value, it is necessary to adjust the dripping amount of the dispersion. The measurement and analysis conditions are set as follows.
Data acquisition count: 15 times Relative refractive index: 1.20
Circulation: 5
Ultrasonic intensity: 7
Ultrasonic irradiation time: 3 minutes

In general, the toner filled in the developing machine is such that the cross-linked resin fine particles on the toner surface are embedded inside the toner or moved to the recesses on the surface of the toner particle main body mainly due to mechanical stress inside the developing machine, The effect of reducing adhesion is lost. Further, when the external additive is exposed to the same stress, it is buried inside the toner, and the adhesion force of the toner is increased.
However, in the toner of the present invention, the crosslinked resin fine particles are relatively large and are not easily embedded in the toner particle body. In particular, it is preferable that the crosslinked resin fine particles are fine particles of a crosslinked resin containing a styrene polymer, an acrylate polymer, or a methacrylic ester polymer, and the glass transition temperature of the fine particles of the crosslinked resin is 50 to 100 ° C. . Since such crosslinked resin fine particles are cross-linked and relatively hard, they do not deform on the surface of the toner particles due to mechanical stress in the developing device, and also maintain the spacer effect, thereby preventing the external additive from being buried. It is more suitable for maintaining the adhesion force of.
The glass transition temperature of the crosslinked resin fine particles is preferably 50 ° C to 100 ° C, more preferably 65 ° C to 85 ° C. When the glass transition temperature is less than 50 ° C., sufficient heat storage stability in the storage temperature range of the toner cannot be obtained, and the toner particles may agglomerate. In some cases, the low-temperature fixability of the toner may be hindered.

  According to the toner production method of the present invention described later, crosslinked resin fine particles are added before or after emulsification. At this timing, since the organic solvent is present in the toner composition droplets, the cross-linked resin particles enter the droplet surface to some extent after adhering to the droplet surface, and after the organic solvent is removed, the particles adhere to the toner surface. It is possible to realize a desirable form. In that case, it is preferable that the zeta potential difference between the anionic resin fine particles and the binder resin fine particles is larger than the zeta potential difference between the crosslinked resin fine particles and the binder resin fine particles.

  Moreover, it is preferable that the said crosslinked resin microparticles | fine-particles have a property which produces | generates an aggregate in the aqueous medium containing the anionic surfactant mentioned later. In the production method of the present invention, when the crosslinked resin fine particles are added to the aqueous medium before emulsification or the emulsified or dispersed liquid after emulsification in the emulsification step, the crosslinked resin fine particles do not adhere to the droplets of the toner material. It is not preferable that they exist independently and stably. Since the crosslinked resin fine particles have the property of forming aggregates in an aqueous medium containing an anionic surfactant, which will be described later, the crosslinked resin fine particles present on the aqueous phase side during or after emulsification are droplets of toner material. It moves to the surface and can easily adhere to the droplet surface of the toner material. That is, in the aqueous medium containing the anionic surfactant, the crosslinked resin fine particles are unstable and usually aggregate, and if there is a toner material droplet, the attractive force with the toner material droplet is reduced. When strong, a complex of foreign particles is formed.

(Fixing aid)
The toner of the present invention preferably contains a crystalline polyester resin as a fixing aid. The crystalline polyester resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a saturated aliphatic diol compound having 2 to 12 carbon atoms as an alcohol component and at least an acidic component as a double bond (C = Examples thereof include crystalline polyesters synthesized using a C2-C12 dicarboxylic acid having a C bond or a C2-C12 saturated dicarboxylic acid.
Examples of the saturated aliphatic diol compound having 2 to 12 carbon atoms include 1,4-butanediol, 1,6-hexanediol, 1, -8 octanediol, 1,10-decanediol, and 1,12 dodecanediol. , And derivatives thereof.
Examples of the dicarboxylic acid having 2 to 12 carbon atoms and the saturated dicarboxylic acid having 2 to 12 carbon atoms include fumaric acid, 1,4-butanedioic acid, 1,6-hexanedioic acid, and 1, -8 octane. Examples thereof include diacid, 1,10-decanedioic acid, 1,12 dodecanedioic acid, and derivatives thereof.

Among the crystalline polyester resins, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, and 1,10-decane are preferable in that the difference between the endothermic peak temperature and the endothermic shoulder temperature is further reduced. Any one alcohol component of diol and 1,12 dodecanediol, fumaric acid, 1,4-butanedioic acid, 1,6-hexanedioic acid, 1,8-octanedioic acid, 1,10-decanedioic acid A crystalline polyester resin synthesized from only one dicarboxylic acid component of either acid or 1,12-dodecanedioic acid is preferred. The melting point of the crystalline polyester resin is preferably 60 ° C to 80 ° C, more preferably 65 ° C to 75 ° C. If the melting point of the crystalline polyester resin is less than 60 ° C., the heat-resistant storage stability may be deteriorated, and if it exceeds 80 ° C., the low-temperature fixability may be deteriorated.
The content of the crystalline polyester in the toner is 1% by mass or more and 20% by mass from the viewpoint that both low-temperature fixability and heat-resistant storage stability can be achieved and toner characteristics such as chargeability and resolution can be maintained at a high level. % Is preferable, and 3% by mass to 10% by mass is more preferable. When the content is less than 1% by mass, the low-temperature fixability may be inferior, and when it is 20% by mass or more, the area of the fixing aid on the toner surface may increase and the fluidity may be inferior. .

[Raw materials used in the production of the toner of the present invention]
(Coloring agent)
There is no restriction | limiting in particular as said coloring agent, According to the objective, it can select suitably from well-known dyes and pigments. For example, 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 Lake, Quinoline Yellow Lake, Anthrazan Yellow BGL , Isoindolinone yellow, bengara, red lead, red lead, cadmium red, cadmium mercury red, antimony red, permanent red 4R, para red, phise red, parachlor ortho nitroaniline red, risor fast scarlet G, Reliant Fast Scarlet, Brilliant Carmine BS, 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, Toluidine 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, Thioindigo Red B, Thioindigo Maroon , Oil red, quinacridone red, pyrazolone red, polyazo red, chrome vermilion, benzidine Range, Perinone Orange, Oil Onji, 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, phthalocyanine green, anthraquinone green, oxidized titanium , Zinc white, litbon, and the like. These may be used individually by 1 type and may use 2 or more types together.

  The content of the colorant in the toner is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1% by mass to 15% by mass, and more preferably 3% by mass to 10% by mass. When the content is less than 1% by mass, a reduction in the coloring power of the toner is observed. When the content exceeds 15% by mass, poor pigment dispersion in the toner occurs, the coloring power decreases, The characteristics may be degraded.

  The colorant may be used as a master batch combined with a resin. The resin is not particularly limited and may be appropriately selected from known ones according to the purpose. For example, polyester, styrene or a substituted polymer thereof, styrene copolymer, polymethyl methacrylate, polymethyl methacrylate, Butyl methacrylate, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, epoxy resin, epoxy polyol resin, polyurethane, polyamide, polyvinyl butyral, polyacrylic acid resin, rosin, modified rosin, terpene resin, aliphatic hydrocarbon resin, alicyclic ring Aromatic hydrocarbon resin, aromatic petroleum resin, chlorinated paraffin, paraffin wax, and the like. These may be used individually by 1 type and may use 2 or more types together.

  Examples of the polymer of styrene or a substituted product thereof include polyester resin, polystyrene, poly p-chlorostyrene, polyvinyl toluene, and the like. Examples of the styrene copolymer include a styrene-p-chlorostyrene copolymer, a styrene-propylene copolymer, a styrene-vinyltoluene copolymer, a styrene-vinylnaphthalene copolymer, and a styrene-methyl acrylate copolymer. Polymer, 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-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene An acrylonitrile-indene copolymer, Styrene - maleic acid copolymer, styrene - maleic acid ester copolymer, and the like.

  The masterbatch can be produced by mixing or kneading the masterbatch resin and the colorant under high shear. At this time, it is preferable to add an organic solvent in order to enhance the interaction between the colorant and the resin. Also, the so-called flushing method is preferable in that the wet cake of the colorant can be used as it is, and there is no need to dry it. This flushing method is a method of mixing or kneading an aqueous paste containing water of a colorant together with a resin and an organic solvent, and transferring the colorant to the resin side to remove moisture and organic solvent components. For the mixing or kneading, for example, a high shear dispersion device such as a three-roll mill is preferably used.

(Other ingredients)
Other components are not particularly limited and may be appropriately selected depending on the intended purpose. For example, release agents, charge control agents, inorganic fine particles, fluidity improvers, cleaning property improvers, magnetic materials, metal soaps , Etc.

-Release agent-
There is no restriction | limiting in particular as said mold release agent, Although it can select suitably according to the objective, Melting | fusing point has a low melting point mold release agent of 50 to 120 degreeC. The low melting point release agent, when dispersed with the resin, effectively acts as a release agent between the fixing roller and the toner interface, thereby preventing oilless (release agent such as oil on the fixing roller). Even if it is not applied), the hot offset property is good.
There is no restriction | limiting in particular as said mold release agent, Although it can select suitably according to the objective, Melting | fusing point has a low melting point mold release agent of 50 to 120 degreeC. The low melting point release agent, when dispersed with the resin, effectively acts as a release agent between the fixing roller and the toner interface, thereby preventing oilless (release agent such as oil on the fixing roller). Even if it is not applied), the hot offset property is good.

  Suitable examples of the mold release agent include waxes and waxes. Examples of the waxes and waxes include plant waxes such as carnauba wax, cotton wax, wood wax and rice wax; animal waxes such as beeswax and lanolin; mineral waxes such as ozokerite and cercin; paraffin and micro wax And natural waxes such as petroleum waxes such as crystallin and petrolatum. In addition to these natural waxes, synthetic hydrocarbon waxes such as Fischer-Tropsch wax and polyethylene wax; synthetic waxes such as esters, ketones and ethers; Furthermore, fatty acid amides such as 12-hydroxystearic acid amide, stearic acid amide, phthalic anhydride imide, chlorinated hydrocarbons; poly-n-stearyl methacrylate and poly-n-lauryl which are low molecular weight crystalline polymer resins A homopolymer or copolymer of a polyacrylate such as methacrylate (for example, a copolymer of n-stearyl acrylate-ethyl methacrylate, etc.); a crystalline polymer having a long alkyl group in the side chain, or the like may be used. These may be used alone or in combination of two or more.

There is no restriction | limiting in particular as melting | fusing point of the said mold release agent, Although it can select suitably according to the objective, 50 to 120 degreeC is preferable and 60 to 90 degreeC is more preferable. When the melting point is less than 50 ° C., the wax may adversely affect the heat resistant storage stability, and when it exceeds 120 ° C., a cold offset may easily occur during fixing at a low temperature.
The melt viscosity of the release agent is preferably 5 cps to 1,000 cps, more preferably 10 cps to 100 cps, as measured at a temperature 20 ° C. higher than the melting point of the wax. If the melt viscosity is less than 5 cps, the releasability may be lowered, and if it exceeds 1,000 cps, the effect of improving hot offset resistance and low-temperature fixability may not be obtained.
There is no restriction | limiting in particular as content in the said toner of the said mold release agent, Although it can select suitably according to the objective, 40 mass% or less is preferable and 3 mass%-30 mass% are more preferable. When the content exceeds 40% by mass, the fluidity of the toner may be deteriorated.

-Charge control agent-
The charge control agent is not particularly limited and may be appropriately selected from known ones according to the purpose. Examples thereof include nigrosine dyes, triphenylmethane dyes, chromium-containing metal complex dyes, and molybdate chelate pigments. , Rhodamine dyes, alkoxy amines, quaternary ammonium salts (including fluorine-modified quaternary ammonium salts), alkylamides, phosphorus alone or compounds thereof, tungsten alone or compounds thereof, fluorine activators, salicylic acid metal salts And metal salts of salicylic acid derivatives. These may be used individually by 1 type and may use 2 or more types together.
Commercially available products may be used as the charge control agent. Examples of the commercially available products include bontron 03 of a nigrosine dye, bontron P-51 of a quaternary ammonium salt, and bontron S-34 of a metal-containing azo dye. , E-82 of oxynaphthoic acid metal complex, E-84 of salicylic acid metal complex, E-89 of phenol condensate (both manufactured by Orient Chemical Co., Ltd.); TP of quaternary ammonium salt molybdenum complex -302, TP-415 (both manufactured by Hodogaya Chemical Co., Ltd.); quaternary ammonium salt copy charge PSY VP2038, triphenylmethane derivative copy blue PR, quaternary ammonium salt copy charge NEG VP2036, Copy charge NX VP434 (both manufactured by Hoechst); LRA-901, boron complex LR-147 (manufactured by Nippon Carlit Co., Ltd.); copper phthalocyanine, perylene, quinacridone, azo pigments, and other polymer compounds having functional groups such as sulfonic acid groups, carboxyl groups, and quaternary ammonium salts. It is done.

  The content of the charge control agent in the toner varies depending on the type of the resin, the presence or absence of an additive, a dispersion method, and the like, and cannot be generally defined. For example, with respect to 100 parts by mass of the binder resin, 0.1 mass part-10 mass parts are preferable, and 0.2 mass part-5 mass parts are more preferable. When the content is less than 0.1 parts by mass, the charge controllability may not be obtained. When the content exceeds 10 parts by mass, the chargeability of the toner becomes too large and the effect of the main charge control agent is reduced. As a result, the electrostatic attractive force with the developing roller increases, which may lead to a decrease in developer fluidity and a decrease in image density.

-Inorganic fine particles-
The inorganic fine particles can be used as an external additive for imparting fluidity, developability, chargeability and the like to toner particles.
The inorganic fine particles are not particularly limited and may be appropriately selected from known ones according to the purpose. For example, silica, alumina, titanium oxide, barium titanate, magnesium titanate, calcium titanate, titanate Strontium, zinc oxide, tin oxide, silica sand, clay, mica, wollastonite, diatomaceous earth, chromium oxide, cerium oxide, pengala, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, barium carbonate, calcium carbonate, carbonized Examples thereof include silicon and silicon nitride. These may be used individually by 1 type and may use 2 or more types together.
The primary particle diameter of the inorganic fine particles is preferably 5 nm to 2 μm, and more preferably 5 nm to 500 nm.
The content of the inorganic fine particles in the toner is preferably 0.01% by mass to 5.0% by mass, and more preferably 0.01% by mass to 2.0% by mass.

-Fluidity improver-
The fluidity improver means a material that can be surface treated to increase hydrophobicity and prevent deterioration of flow characteristics and charging characteristics even under high humidity. For example, a silane coupling agent, a silylating agent, Examples thereof include a silane coupling agent having a fluoroalkyl group, an organic titanate coupling agent, an aluminum coupling agent, silicone oil, and modified silicone oil. It is particularly preferable that the silica and the titanium oxide are surface-treated with such a fluidity improver and used as hydrophobic silica and hydrophobic titanium oxide.

-Cleaning improver-
The cleaning improver is added to the toner in order to remove the developer after transfer remaining on the photoreceptor or the primary transfer medium, and includes, for example, fatty acid metal salts such as zinc stearate, calcium stearate, stearic acid, and the like. Examples thereof include polymer fine particles produced by soap-free emulsion polymerization such as methyl methacrylate fine particles and polystyrene fine particles. The polymer fine particles preferably have a relatively narrow particle size distribution, and those having a volume average particle size of 0.01 μm to 1 μm are suitable.

-Magnetic material-
There is no restriction | limiting in particular as said magnetic material, According to the objective, it can select suitably from well-known things, For example, iron powder, a magnetite, a ferrite, etc. are mentioned. Among these, white is preferable in terms of color tone.

[Method for Producing Toner of the Present Invention]
The toner particles of the present invention comprise a binder resin containing at least a copolymer of the non-crystalline polyester and poly L-lactic acid, a colorant, and a crystallization nucleating agent for the poly L-lactic acid in an organic solvent. It is obtained by dissolving or dispersing the contained toner material, emulsifying or dispersing an oil phase comprising the dissolved or dispersed toner material in an aqueous medium, and removing the organic solvent from the dispersion obtained by granulation. It is preferable.
Therefore, the method for producing a toner of the present invention comprises an oil solution comprising a dissolution / dispersion step in which a toner material containing a binder resin and a colorant is dissolved or dispersed in at least an organic solvent, and a solution or dispersion of the toner material. An emulsion dispersion step of emulsifying or dispersing the phase in an aqueous medium and granulating; and an organic solvent removal step of removing the organic solvent, wherein the binder resin has a glass transition point of −20 ° C. or more and 35 ° C. or less. A copolymer of non-crystalline polyester and poly L-lactic acid, the content of poly L-lactic acid is 50% by mass or more and 80% by mass or less of the total binder resin, and poly L-lactic acid in an organic solvent. As a crystallization nucleating agent for lactic acid, it is preferable to contain a crystalline resin of an optical isomer (D-form) of poly L-lactic acid and / or an organic compound containing a structure of an optical isomer (D-form) of poly L-lactic acid. .
In the method for producing a toner of the present invention, a solution or dispersion formed by dissolving or dispersing a toner material mainly composed of a binder resin and a colorant in an organic solvent is used as an anionic resin fine particle and a crosslinked resin. Emulsifying or dispersing in an aqueous medium containing fine particles to prepare an emulsified or dispersed liquid, granulating, adhering the crosslinked resin fine particles to the toner precursor containing the emulsified or dispersed toner material, and then removing the organic solvent; It is preferable to produce a desired toner by heat-treating water containing the toner particles after the toner particles are formed.

(Dissolution or dispersion of toner material)
The solution or dispersion of the toner material is prepared by dissolving or dispersing the toner material in a solvent. The toner material includes, for example, the above-described binder resin, colorant, crystallization nucleating agent, and fixing aid, and further includes other components such as a release agent and a charge control agent as necessary. May be. The toner material dissolved or dispersed liquid is preferably prepared by dissolving or dispersing the toner material in an organic solvent. The organic solvent is preferably removed during or after the toner granulation.

(Organic solvent)
The organic solvent that dissolves or disperses the toner material is not particularly limited as long as it is a solvent that can dissolve or disperse the toner material, and can be appropriately selected according to the purpose. Preferred are those having a boiling point of less than 150 ° C. from the viewpoint of ease of removal, for example, toluene, xylene, benzene, carbon tetrachloride, methylene chloride, 1,2-dichloroethane, 1,1,2-trichloroethane, trichloroethylene, chloroform Monochlorobenzene, dichloroethylidene, methyl acetate, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, and the like can be used. Further, ester solvents are preferable, and ethyl acetate is particularly preferable. These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular as the usage-amount of an organic solvent, Although it can select suitably according to the objective, 40-300 mass parts is preferable with respect to 100 mass parts of toner materials, 60-140 mass parts is more preferable, 80 -120 mass parts is more preferable.
The dissolution or dispersion of the toner material can be performed by dissolving or dispersing toner materials such as a binder resin, a release agent, a colorant, and a charge control agent in an organic solvent. In addition, the toner material may be added and mixed in the aqueous medium in the preparation of the aqueous medium described later. Alternatively, when the dissolved or dispersed liquid of the toner material is added to the aqueous medium, It may be added to the medium.

(Aqueous medium)
The aqueous medium is not particularly limited and can be appropriately selected from known ones. For example, water, a solvent miscible with water, a mixture thereof, and the like can be used. Is particularly preferred. The solvent miscible with water is not particularly limited as long as it is miscible with water. For example, alcohol, dimethylformamide, tetrahydrofuran, cellosolves, lower ketones, and the like can be used. Examples of the alcohol include methanol, isopropanol, and ethylene glycol. Examples of lower ketones include acetone and methyl ethyl ketone. These may be used individually by 1 type and may use 2 or more types together.

  The aqueous medium is prepared, for example, by dispersing the anionic resin fine particles in the aqueous medium in the presence of an anionic surfactant. There is no restriction | limiting in particular as the addition amount to the aqueous medium of an anionic surfactant and anionic resin fine particle, According to the objective, it can select suitably, For example, 0.5-10 mass% is respectively preferable. The crosslinked resin fine particles are preferably added to the aqueous medium thereafter. When the crosslinked resin fine particles have an aggregating property with the anionic surfactant, the aqueous medium is preferably dispersed with a high-speed shearing disperser before emulsification.

(Anionic surfactant)
Examples of the anionic surfactant used in the production of the toner of the present invention include alkylbenzene sulfonates, α-olefin sulfonates, phosphate esters and the like, and anionic surfactants having a fluoroalkyl group include Preferably mentioned. Examples of the anionic surfactant having a fluoroalkyl group include a fluoroalkylcarboxylic acid having 2 to 10 carbon atoms or a metal salt thereof, disodium perfluorooctanesulfonylglutamate, 3- [ω-fluoroalkyl (having 6 to 6 carbon atoms). 11) Sodium oxy] -1-alkyl (C3-4) sulfonate, sodium 3- [ω-fluoroalkanoyl (C6-8) -N-ethylamino] -1-propanesulfonate, fluoroalkyl ( Carbon number 11-20) carboxylic acid or metal salt thereof, perfluoroalkyl carboxylic acid (carbon number 7-13) or metal salt thereof, perfluoroalkyl (carbon number 4-12) sulfonic acid or metal salt thereof, perfluorooctane Sulfonic acid diethanolamide, N-propyl-N- (2-hydroxyethyl) par -Fluorooctanesulfonamide, perfluoroalkyl (carbon number 6-10) sulfonamidopropyltrimethylammonium salt, perfluoroalkyl (carbon number 6-10) -N-ethylsulfonylglycine salt, monoperfluoroalkyl (carbon number 6-6) 16) Ethyl phosphate and the like.

  Examples of commercially available anionic surfactants having a fluoroalkyl group include Surflon S-111, S-112, and S-113 (Asahi Glass Co., Ltd.); Fluorard FC-93, FC-95, FC-98, FC -129 (manufactured by Sumitomo 3M); Unidyne DS-101, DS-102 (manufactured by Daikin Industries); Megafac F-110, F-120, F-113, F-191, F-812, F-833 ( Dainippon Ink Co.); Xtop EF-102, 103, 104, 105, 112, 123A, 123B, 306A, 501, 201, 204 (manufactured by Tochem Products); Etc.).

(Anionic resin fine particles)
The resin for resin fine particles used in the present invention is not particularly limited as long as it can form an aqueous dispersion in an aqueous medium, and can be appropriately selected from known resins according to the purpose. The resin for resin fine particles may be a thermoplastic resin or a thermosetting resin. For example, vinyl resin, polyurethane resin, epoxy resin, polyester resin, polyamide resin, polyimide resin, silicon resin, phenol resin, melamine resin Urea resin, aniline resin, ionomer resin, polycarbonate resin, and the like can be used. These may be used individually by 1 type and may use 2 or more types together. Among these, at least one selected from vinyl resins, polyurethane resins, epoxy resins, and polyester resins is preferable because an aqueous dispersion of fine spherical resin fine particles can be easily obtained. The vinyl resin is a polymer obtained by homopolymerizing or copolymerizing a vinyl monomer. For example, a styrene- (meth) acrylic ester resin, a styrene-butadiene copolymer, a (meth) acrylic acid-acrylic ester polymer, Examples thereof include a styrene-acrylonitrile copolymer, a styrene-maleic anhydride copolymer, and a styrene- (meth) acrylic acid copolymer.

  The resin fine particles are required to be anionic. This is because they are not aggregated when used together with the anionic surfactant shown above. The resin fine particles can also be prepared by using an anionic activator by a production method described later or by introducing an anionic group such as a carboxylic acid group or a sulfonic acid group into the resin. As the particle size, an average particle size of primary particles of 5 to 50 nm is important for controlling the particle size and particle size distribution of the emulsified particles, and more preferably 10 to 25 nm. The particle diameter can be measured by SEM, TEM, light scattering method or the like. Preferably, the measurement may be performed by diluting to an appropriate concentration so as to be in the measurement range by LA-920 manufactured by HORIBA, Ltd. using a laser scattering measurement method. The particle diameter is determined as a volume average diameter.

The resin fine particles can be obtained by polymerization according to a known method appropriately selected according to the purpose, but is preferably obtained as an aqueous dispersion of resin fine particles. As a method for preparing an aqueous dispersion of resin fine particles, for example, the following method is preferably exemplified.
(1) In the case of vinyl resin, aqueous dispersion of resin fine particles A directly by a polymerization reaction selected from a suspension polymerization method, an emulsion polymerization method, a seed polymerization method and a dispersion polymerization method using a vinyl monomer as a starting material (2) Polyaddition or condensation resins such as polyester resins, polyurethane resins, epoxy resins, etc. In the case of a polyaddition or condensation resin, a precursor (monomer, oligomer, etc.) or a solvent solution thereof in the presence of a suitable dispersant in an aqueous medium A method for producing an aqueous dispersion of resin fine particles by dispersing in, then heating or adding a curing agent to cure.

(3) In the case of polyaddition or condensation resin such as polyester resin, polyurethane resin, epoxy resin, etc., a precursor (monomer, oligomer, etc.) or a solvent solution thereof (preferably liquid. It may be liquefied by heating). A method in which a suitable emulsifier is dissolved therein and then water is added to carry out phase inversion emulsification. (4) A polymerization reaction (addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) The resin prepared by (1) may be pulverized using a mechanical pulverizer or jet pulverizer and then classified to obtain resin fine particles, which are then dispersed in water in the presence of an appropriate dispersant. How to make

(5) A spray of a resin solution prepared by previously dissolving a resin prepared in a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent. A method of dispersing resin fine particles in water in the presence of an appropriate dispersant after obtaining resin fine particles (6) Polymerization reaction (addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in advance Any polymerization reaction mode may be used) to add a poor solvent to a resin solution prepared by dissolving a resin prepared in a solvent, or by cooling a resin solution previously dissolved in a solvent to precipitate resin fine particles, Next, after removing the solvent to obtain resin fine particles, the resin fine particles are dispersed in water in the presence of an appropriate dispersant.

(7) A resin solution prepared by previously dissolving a resin prepared by a polymerization reaction (any polymerization reaction mode such as addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) in a solvent is appropriately dispersed. A method of removing the solvent by heating or decompression after being dispersed in an aqueous medium in the presence of an agent (8) Any polymerization reaction such as prepolymerization reaction (addition polymerization, ring-opening polymerization, polyaddition, addition condensation, condensation polymerization, etc.) A suitable emulsifier is dissolved in a resin solution prepared by dissolving a resin prepared in a solvent in a solvent, and water is added to perform phase inversion emulsification.

(Emulsification or dispersion)
The dissolution or dispersion of the toner material in the aqueous medium is preferably carried out by dispersing the toner material dissolution or dispersion in the aqueous medium while stirring. There is no restriction | limiting in particular as a dispersion method, According to the objective, it can select suitably, For example, it can carry out using a well-known disperser etc. Examples of the disperser include a low speed shear disperser and a high speed shear disperser. In this toner production method, the crosslinked resin fine particles may be added to the aqueous medium during or after emulsification during emulsification or dispersion. It is carried out while dispersing with a high-speed shearing disperser, or by switching to low-speed stirring after emulsification, or appropriately while checking the adhesion of the crosslinked resin fine particles to the toner and the immobilization state.

  The organic solvent is removed from the obtained dispersion (emulsified slurry). The organic solvent is removed by (1) a method of gradually raising the temperature of the entire reaction system to completely evaporate and remove the organic solvent in the oil droplets, and (2) spraying the emulsified dispersion in a dry atmosphere. And a method of completely removing the water-insoluble organic solvent in the oil droplets to form toner fine particles and evaporating and removing the aqueous dispersant together.

  When the organic solvent is removed, toner particles are formed. The toner particles can be washed, dried, etc., and then classified as desired. The classification can be performed, for example, by removing fine particle portions by a cyclone, a decanter, centrifugation, or the like in a liquid, and the classification operation may be performed after obtaining a powder after drying.

The obtained toner particles are mixed with particles of the colorant, the release agent, the charge control agent, and the like, or further applied with a mechanical impact force to thereby release the release agent from the surface of the toner particles. Can be prevented from being detached.
As the method for applying the mechanical impact force, for example, a method in which an impact force is applied to the mixture by a blade rotating at high speed, a mixture is injected into a high-speed air stream, and the particles are combined with each other or composite particles are appropriately used. The method of making it collide with a collision board, etc. are mentioned. As an apparatus used in this method, for example, an ong mill (manufactured by Hosokawa Micron Co., Ltd.), an I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) and a pulverization air pressure is lowered, and a hybridization system (Nara Machinery). Manufactured by Seisakusho), kryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, and the like.

  The volume average particle diameter of the toner is preferably 3 μm to 10 μm, and the ratio (Dv / Dn) of the volume average particle diameter (Dv) to the number average particle diameter (Dn) is 1.00 to 1. .30 is preferred. By defining the volume average particle diameter and the ratio (Dv / Dn) in this way, it is possible to obtain a toner with high resolution and high image quality. In order to obtain a higher quality image, the volume average particle diameter of the toner is preferably 3 μm to 7 μm, and the ratio (Dv / Dn) is preferably 1.17 or less. Is more preferably 4 μm to 7 μm, and the Dv / Dn is more preferably 1.15 or less. Such a toner is free from scattering and fog, especially when a full-color copying machine or the like is used, and can form a high-quality image with good developability over the long term.

[Toner characteristics measurement method]
<Weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn)>
The weight average particle diameter (Dw), volume average particle diameter (Dv), and number average particle diameter (Dn) of the toner were measured using a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) with an aperture diameter of 100 μm. It measured and analyzed with the analysis software (Beckman Coulter Multisizer 3 Version3.51). Specifically, 0.5 ml of 10 wt% surfactant (alkylbenzene sulfonate Neogen SC-A; Daiichi Kogyo Seiyaku) was added to a glass 100 ml beaker, 0.5 g of each toner was added, and the mixture was stirred with a micropartel. Subsequently, 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured using the Multisizer III and Isoton III (manufactured by Beckman Coulter) as the measurement solution. In the measurement, the toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8 ± 2%. In this measurement method, it is important that the concentration is 8 ± 2% from the viewpoint of the reproducibility of the particle size. Within this concentration range, no error occurs in the particle size.

(Measurement of glass transition point)
Device: DSC (TA Instruments, Q2000)
What filled 5-10 mg of samples in the aluminum simple airtight bread | pan was used for the following measurement flows.
1st Heating: 30 ° C. to 220 ° C., 5 ° C./min, 1 minute hold after reaching 220 ° C. Cooling: quench to −50 ° C., hold for 1 minute after reaching −20 ° C. 2nd Heating: −50 ° C. to 180 ° C., 5 ° C. / min.
The glass transition point was read as a glass transition point by adopting a midpoint method in a 2nd Heating thermogram and reading the value.

  The full-color image forming method according to the present invention includes a charging step of charging an electrophotographic photosensitive member with a charging unit, an exposure step of forming an electrostatic latent image on the charged electrophotographic photosensitive member with an exposing unit, and the static A developing step of forming a toner image on the electrophotographic photosensitive member on which the electro-latent image has been formed by a developing unit containing toner, and a toner image formed on the electrophotographic photosensitive member on the intermediate transfer member by a primary transfer unit A primary transfer step of transferring, a secondary transfer step of transferring a toner image transferred onto the intermediate transfer member onto a recording material by a secondary transfer means, and a heat and pressure of the toner image transferred onto the recording material A fixing step of fixing on a recording material by a fixing means including a fixing member; and a transfer residual toner adhering to the surface of the electrophotographic photosensitive member having the toner image transferred onto the intermediate transfer member by the primary transfer means. It is preferable that a cleaning step of cleaning the grayed means. The toner in the developing process is the above-described toner of the present invention. In this full-color image forming method, the linear speed of transfer of the toner image to the recording material in the secondary transfer step, the so-called printing speed is 100 to 1000 mm / sec, and the transfer time at the nip portion of the secondary transfer means is 0. It is preferably 5 to 60 msec.

  Furthermore, the full-color image forming method according to the present invention is preferably a tandem type having a plurality of sets of an electrophotographic photosensitive member, a charging unit, an exposure unit, a developing unit, a primary transfer unit, and a cleaning unit. In a so-called tandem type in which a plurality of electrophotographic photosensitive members are arranged and developed one color at a time of each rotation, a latent image forming process and a developing / transfer process are performed for each color to form a toner image of each color. Therefore, the difference between the single-color image forming speed and the full-color image forming speed is small, and there is an advantage that it can cope with high-speed printing. However, since each color toner image is formed on a separate electrophotographic photosensitive member and each color toner layer is stacked (color overlap) to form a full color image, the chargeability between the toner particles of each color is different. If the characteristics are varied, a difference occurs in the amount of toner developed by toner particles of each color, and the change in the hue of the secondary color due to color superposition is increased, resulting in a decrease in color reproducibility.

  In the toner used in the tandem type image forming method, the amount of developing toner for controlling the balance of each color is stabilized (there is no variation among the toner particles of each color), and the toner between the toner particles of each color is electronic. The adhesion to the photographic photosensitive member and the recording material is required to be uniform. In this regard, the toner of the present invention is suitable.

  The charging means preferably applies at least a DC voltage on which an alternating voltage is superimposed. By applying a DC voltage superimposed with an alternating voltage, the surface voltage of the electrophotographic photosensitive member can be stabilized to a desired value compared to the case where only a DC voltage is applied. It becomes. Further, the charging means preferably performs charging by bringing a charging member into contact with the electrophotographic photosensitive member and applying a voltage to the charging member. By further charging the electrophotographic photosensitive member with a charging member and applying a voltage to the charging member to perform charging, in particular, the effect of uniform charging obtained by applying a DC voltage superimposed with an alternating voltage can be further improved. Is possible.

  The fixing means is composed of a magnetic metal and heated by electromagnetic induction, is stretched between the fixing roller arranged in parallel with the heating roller, the heating roller and the fixing roller, and is heated by the heating roller. An endless belt-shaped toner heating medium (heating belt) rotated by these rollers is pressed against the fixing roller via the heating belt and is rotated in the forward direction with respect to the heating belt to form a fixing nip portion. By having the pressure roller, the temperature of the fixing belt rises in a short time, and stable temperature control becomes possible. Even when a recording material having a rough surface is used, the fixing belt acts in a state corresponding to the surface of the transfer paper to some extent at the time of fixing, so that sufficient fixing property can be obtained.

  The fixing means is preferably oilless or a small amount of oil application type. In order to achieve this, it is preferable to fix the toner particles containing a release agent (WAX) and further finely dispersed in the toner particles. In the case where the release agent is easily leached during fixing due to the toner in which the release agent is dispersed in a small amount in the toner particles, and the oil application effect is reduced in the oil-less fixing device or in the trace amount oil application fixing device. Also, the transfer of toner to the belt side can be suppressed. In order for the release agent to be dispersed in the toner particles, it is preferable that the release agent and the binder resin are not compatible. In order to finely disperse the release agent in the toner particles, for example, there is a method of pulverizing with a bead mill or the like in a step of dissolving or dispersing the toner material in an organic solvent at the time of toner production. The dispersion state of the release agent can be determined by observing a thin film slice of toner particles with a TEM. The dispersion diameter of the release agent is preferably small, but if it is too small, there are cases where the seepage during fixing is insufficient. Therefore, if the release agent can be confirmed at a magnification of 10,000, it is determined that the release agent exists in a dispersed state. If the size is 10,000 times and the release agent cannot be confirmed, even if finely dispersed, there is a case where the bleeding at the time of fixing is insufficient.

<Calculation method and analysis method of various characteristics of toner and toner component>
The Tg, acid value, hydroxyl value, molecular weight, and melting point of the copolymer of the non-crystalline polyester and poly L-lactic acid, the crystalline polyester resin, and the release agent may be measured on their own. However, it is possible to calculate the Tg, molecular weight, melting point, and mass ratio of the constituent components by separating the actual toner by gel permeation chromatography (GPC) or the like and using the analysis method described below for each separated component. Good.

Separation of each component by GPC can be performed, for example, by the following method.
In GPC measurement using THF (tetrahydrofuran) as a mobile phase, the eluate is fractionated by a fraction collector or the like, and fractions corresponding to a desired molecular weight portion of the entire surface of the elution curve are collected.
After concentrating and drying the collected eluate with an evaporator or the like, the solid content is dissolved in a heavy solvent such as deuterated chloroform or deuterated THF, and ¹ H-NMR measurement is performed. The constituent monomer ratio of is calculated.
As another method, after concentrating the eluate, it is hydrolyzed with sodium hydroxide or the like, and the decomposition product is subjected to qualitative quantitative analysis by high performance liquid chromatography (HPLC) to calculate the constituent monomer ratio.

<< Toner component separation means >>
An example of the separation means for each component when analyzing the toner will be described in detail.
First, 1 g of toner is put into 100 mL of THF, and a solution in which the soluble components are dissolved is obtained while stirring for 30 minutes at 25 ° C.
This is filtered through a membrane filter having an opening of 0.2 μm to obtain a THF soluble component in the toner.
Subsequently, this is melt | dissolved in THF, it is set as the sample for GPC measurement, and it inject | pours into GPC used for the molecular weight measurement of each above-mentioned resin.
On the other hand, a fraction collector is placed at the eluate discharge port of GPC, and the eluate is collected every predetermined count, and the eluate is eluted every 5% in area ratio from the elution curve elution start (curve rise). Get.
Next, for each elution, 30 mg of sample is dissolved in 1 mL of deuterated chloroform, and 0.05% by volume of tetramethylsilane (TMS) is added as a reference substance.
The solution is filled in a 5 mm diameter glass tube for NMR measurement, and a spectrum is obtained by performing integration 128 times at a temperature of 23 ° C. to 25 ° C. using a nuclear magnetic resonance apparatus (JNM-AL400 manufactured by JEOL Ltd.). .

The monomer composition and composition ratio of the amorphous polyester resin and the crystalline polyester resin contained in the toner can be obtained from the peak integration ratio of the obtained spectrum.
For example, peak assignment is performed as follows, and the component ratio of the constituent monomer is determined from each integral ratio.
The attribution of the peak is, for example,
Near 8.25 ppm: derived from benzene ring of trimellitic acid (for one hydrogen)
8.07 ppm to around 8.10 ppm: derived from benzene ring of terephthalic acid (for 4 hydrogens)
7.1 ppm to 7.25 ppm vicinity: derived from benzene ring of bisphenol A (for 4 hydrogens)
Around 6.8 ppm: derived from benzene ring of bisphenol A (for 4 hydrogens) and from double bond of fumaric acid (for 2 hydrogens)
5.2 ppm to around 5.4 ppm: derived from methine of PLA methylene group and bisphenol A propylene oxide adduct (one hydrogen)
3.7 ppm to around 4.7 ppm: bisphenol A propylene oxide adduct derived from methylene (for 2 hydrogens) and bisphenol A ethylene oxide adduct derived from methylene (for 4 hydrogens)
Around 1.6 ppm: derived from PLA methyl group and bisphenol A methyl group (for 6 hydrogens)
It can be.

From these results, for example, an extract recovered in a fraction in which the copolymerization of the amorphous polyester and poly L-lactic acid accounts for 90% or more is used as a copolymer of the amorphous polyester and poly L-lactic acid. Can be treated as Similarly, the extract recovered in the fraction in which the crystalline polyester resin accounts for 90% or more can be treated as the crystalline polyester resin.
Further, when the extract recovered in the fraction in which the copolymerization of the non-crystalline polyester and poly-L-lactic acid accounts for 90% or more is analyzed by reaction pyrolysis gas chromatography / mass spectrometry, a chiral column is used. It is possible to quantify not only the PLA component contained in the polymerization but also the optical purity.

<NMR>
The resin component was dissolved in deuterated chloroform at as high a concentration as possible and then placed in an NMR sample tube having a diameter of 5 mm, and an NMR spectrum was measured. As a measuring device, JNM-ECX-300 (manufactured by JEOL Resonance) is used. ^When measuring the ¹ HNMR spectrum, the measurement temperature is 30 ° C., the number of integrations is 256 times, and the repetition time is 5.0 s. ^When measuring a ¹³ C NMR spectrum, the measurement temperature is 30 ° C., the number of integrations is 10,000 times, and the repetition time is 1.5 s. Components can be attributed from the chemical shift obtained, and the blending ratio can be calculated from a numerical value obtained by dividing the integrated value of the corresponding peak by the number of protons or carbon.

<GC / MS>
Measurement is performed under the following conditions using QP2010 (manufactured by Shimadzu Corporation) as a measurement apparatus, GCMSsolution (manufactured by Shimadzu Corporation) as data analysis software, and Py2020D (manufactured by Frontier Laboratories) as a heating apparatus.
Reaction pyrolysis temperature: 300 ° C
Column: IntertCapCHIRAMIX L = 30 m ID = 0.25 mm Film = 0.25 μm
Column heating: 50 ° C. (holding 1 min) to 10 ° C./min to 150 ° C. (holding 11 min)
Carrier gas pressure: 53.6 kPa (constant)
Column flow rate: 1.0 mL / min
Ionization method: EI method (70 eV)
Mass range (m / z): 29-700
Injection mode: Split (1: 100)

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In addition, a part represents a mass part.

(Synthesis Example 1)
-Synthesis of polyester resin A1-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 68.0 parts by mass of an ethylene oxide 2-mole adduct of bisphenol A, 2.4 parts by mass of trimellitic anhydride, 22.9 parts by mass of adipic acid, isophthalic acid 6.5 parts by mass of acid and 0.2 parts by mass of dibutyltin oxide were added, reacted at 230 ° C. for 4 hours under normal pressure, and then reacted for 5 hours under reduced pressure of 10 mmHg to 15 mmHg to obtain polyester resin A1. The resulting polyester resin A1 was amorphous and had a glass transition point of 30.5 ° C.

(Synthesis Examples 2 to 5)
-Synthesis of polyester resins A2-A5-
Polyester resins A2 to A5 were respectively synthesized in the same manner as in Synthesis Example 1 except that the amount of the polyester resin material was adjusted as shown in Table 1 below in Synthesis Example 1. The obtained polyester resins A2 to A5 were non-crystalline, and the glass transition point was measured in the same manner as the polyester resin A1. The results are shown in Table 2.

(Synthesis Example 6)
-Synthesis of poly L-lactic acid resin B1-
100 parts by mass of L-lactide (optical purity 98%) was put into a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, the internal temperature was gradually raised to 50 ° C., and then dehydrated at 10 mmHg for 30 min. Processed. Next, the temperature was raised to 170 ° C. under N ₂ purge, and after confirming that the system was homogenized by visual observation, 0.2 parts by mass of tin 2-ethylhexanoate and 1.0 part by mass of ethylene glycol were added. The polymerization reaction was carried out. At this time, the internal temperature of the system was controlled so as not to exceed 190 ° C. After the reaction time of 2 hours, delactide was carried out under the conditions of 190 ° C. and 10 mmHg to complete the polymerization reaction, whereby Resin B1 was obtained. The weight average molecular weight was 15100, and the endothermic peak was 145 ° C.

(Synthesis Example 7)
-Synthesis of poly L-lactic acid resin B2-
In Synthesis Example 6, poly-L-lactic acid resin B2 was synthesized in the same manner as in Synthesis Example 6 except that the optical purity of L-lactide used was 94%. The weight average molecular weight was 14200, and the endothermic peak was 141 ° C.

(Synthesis Example 8)
-Synthesis of poly L-lactic acid resin B3-
In Synthesis Example 6, a poly L-lactic acid resin B3 was synthesized in the same manner as in Synthesis Example 6 except that the optical purity of L-lactide used was 88%. The weight average molecular weight was 14700, and the endothermic peak was 140 ° C.

(Synthesis Example 9)
-Synthesis of binder resin C1-
In a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introducing tube, 40 parts by mass of polyester lactic acid A1 was charged, dehydrated at 100 ° C. and 10 mmHg for 30 minutes, and then heated to 180 ° C. Next, after adding 60 parts by mass of poly L-lactic acid resin B1 and stirring until it is melted and homogenized, 0.1 part by mass of tin 2-ethylhexanoate is added and reacted at 180 ° C. and 10 mmHg for 2 hours to produce a binder resin. C1 was synthesized.

(Synthesis Examples 10-18)
-Synthesis of binder resins C2 to C10-
As shown in Table 3 below in Synthesis Example 9, binder resins C2 to C10 were respectively synthesized in the same manner as Synthesis Example 9 except that the type and mass part of the binder resin material were adjusted.

(Synthesis Example 19)
-Synthesis of crosslinked resin fine particles D1-
In a reaction vessel equipped with a stir bar and a thermometer, 683 parts by mass of water, 10 parts by mass of distearyldimethylammonium chloride (cation DS, manufactured by Kao), 144 parts by mass of methyl methacrylate, 50 parts by mass of butyl acrylate, ethylene glycol diester When 4 parts by weight of methacrylate and 1 part by weight of ammonium persulfate were charged and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The mixture was heated to raise the temperature in the system to 65 ° C. and reacted for 10 hours. Further, 30 parts by mass of a 1% by mass ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours to be a vinyl resin (copolymer of methyl methacrylate-butyl acrylate-ethylene glycol dimethacrylate) [crosslinked resin fine particles D1 An aqueous dispersion was obtained. [Crosslinked resin fine particle D1] had a volume average particle size (measured with LA-920, manufactured by Horiba, Ltd.) of 60 nm and Tg of 79.1 ° C.

(Synthesis Examples 20 to 21)
-Synthesis of crosslinked resin fine particles D2-D3-
As shown in Table 4 below in Synthesis Example 19, crosslinked resin fine particles D2 to D3 were synthesized in the same manner as in Synthesis Example 19 except that the input amount of the crosslinked resin fine particle D1 material was adjusted. The obtained crosslinked resin fine particles D2 to D3 were measured for volume average particle diameter and glass transition point in the same manner as the crosslinked resin fine particles D1. The results are shown in Table 5.

~ Synthesis of anionic resin fine particles ~
In a reaction vessel in which a stir bar and a thermometer were set, 683 parts of water, 16 parts of sodium salt of ethylene oxide methacrylate adduct sulfate (Eleminol RS-30, manufactured by Sanyo Chemical Industries), 83 parts of styrene, 83 parts of methacrylic acid, When 110 parts of butyl acrylate and 1 part of ammonium persulfate were added and stirred at 400 rpm for 15 minutes, a white emulsion was obtained. The system was heated to raise the system temperature to 75 ° C. and reacted for 5 hours. Further, 30 parts of a 1% ammonium persulfate aqueous solution was added, and the mixture was aged at 75 ° C. for 5 hours, and an aqueous vinyl resin (a copolymer of styrene-methacrylic acid-butyl acrylate-methacrylic acid ethylene oxide adduct sulfate sodium salt). A dispersion [resin fine particle dispersion A1] was obtained. The volume average particle diameter of the [resin fine particle dispersion A1] (measured with LA-920 manufactured by Horiba, Ltd.) was 38 nm, the weight average molecular weight was 420,000, and Tg was 63 ° C.

-Synthesis of crystallization nucleating agent (poly D-lactic acid)-
Into a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introducing tube, 100 parts by mass of D-lactide was added, and the internal temperature was gradually raised to 50 ° C., followed by dehydration treatment at 10 mmHg for 30 min. Next, the temperature was raised to 170 ° C. under N ₂ purge, and after confirming that the system was homogenized by visual observation, 0.2 parts by mass of tin 2-ethylhexanoate and 1.0 part by mass of ethylene glycol were added. The polymerization reaction was carried out. At this time, the internal temperature of the system was controlled so as not to exceed 190 ° C. After the reaction time of 2 hours, delactide was performed under the conditions of 190 ° C. and 10 mmHg to complete the polymerization reaction, thereby obtaining a poly D-lactic acid resin. The weight average molecular weight was 13700.

~ Synthesis of crystalline polyester resin ~
Into a reaction vessel equipped with a cooling tube, a stirrer, and a nitrogen introduction tube, 67.3 parts by mass of sebacic acid, 32.7 parts by mass of 1,6-hexanediol and 0.2 parts by mass of dibutyltin oxide were charged under normal pressure. After making it react at 230 degreeC for 4 hours, it was made to react under reduced pressure of 10 mmHg-15 mmHg for 5 hours, and crystalline polyester resin was obtained.

Example 1
-Preparation of master batch (MB)
1000 parts by weight of water, 540 parts by weight of carbon black (“Printex35”; manufactured by Degussa, DBP oil absorption = 42 ml / 100 g, pH = 9.5), 1200 parts by weight of binder resin C1, Henschel mixer (Mitsui Mine Mixed). The mixture was kneaded with two rolls at 150 ° C. for 30 minutes, rolled and cooled, and pulverized with a pulverizer (manufactured by Hosokawa Micron) to prepare a master batch.

-Preparation of aqueous medium phase-
660 parts by weight of water, 25 parts by weight of the anionic resin fine particle dispersion [resin fine particle dispersion A1], 48.5% by weight aqueous solution of sodium dodecyl diphenyl ether disulfonate (“Eleminol MON-7”; manufactured by Sanyo Chemical Industries) 25 Part by mass and 60 parts by mass of ethyl acetate were mixed and stirred to obtain a milky white liquid (aqueous phase). Furthermore, 50 mass parts of crosslinked resin fine particles D1 were added. When observed with an optical microscope, several hundred μm aggregates were observed. When this aqueous medium phase was stirred at 8000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), it was confirmed by an optical microscope that the aggregates were loosened and could be dispersed into small aggregates of several μm. Therefore, in the subsequent emulsification step of the toner material, it was expected that the crosslinked resin fine particles D1 were dispersed and adhered to the toner material component droplets. As described above, the crosslinked resin fine particles D1 cause aggregation but are loosened by shearing, which is important for uniform adhesion to the toner surface.

-Preparation of toner material phase-
In a beaker, 100 parts by mass of the binder resin C1, 5 parts by mass of poly-D-lactic acid, 10 parts by mass of a crystalline polyester resin, and 130 parts by mass of ethyl acetate were stirred and dissolved. Next, 10 parts by mass of carnauba wax (molecular weight = 1,800, acid value = 2.5, penetration = 1.5 mm (40 ° C.)) and 10 parts by mass of the master batch were charged, and a bead mill (“Ultra Visco” Mill ”(manufactured by Imex Co., Ltd.) was used to prepare a raw material solution by performing 6 passes under the conditions of a liquid feeding speed of 1 kg / hr, a disk peripheral speed of 6 m / s and 80% by volume of 0.5 mm zirconia beads. Material Dissolution or Dispersion] was prepared.

~ Emulsification or preparation of dispersion ~
150 parts by mass of the aqueous medium phase is placed in a container, and stirred at a rotational speed of 12,000 rpm using a TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), and 100 parts by mass of the solution or dispersion of the toner material is added thereto. The mixture was added and mixed for 10 minutes to prepare an emulsified dispersion (emulsified slurry).

~ Removal of organic solvent ~
Into a flask equipped with a deaeration pipe, a stirrer and a thermometer, 100 parts by mass of the emulsified slurry was charged, and the solvent was removed under reduced pressure at 30 ° C. for 12 hours while stirring at a stirring peripheral speed of 20 m / min. did.

~Washing~
After filtering the whole amount of the solvent removal slurry under reduced pressure, 300 parts by mass of ion-exchanged water was added to the filter cake, mixed and redispersed (at 12,000 rpm for 10 minutes) with a TK homomixer, and then filtered. Addition of 300 parts by mass of ion-exchanged water to the obtained filter cake, mixing with a TK homomixer (at 12,000 rpm for 10 minutes) and then filtering three times, the conductivity of the redispersed slurry Was 0.1 μS / cm or more and 10 μS / cm or less to obtain a cleaning slurry.

~ Heat treatment ~
After fixing the fine particles D1 adhering to the toner surface by heating in a flask equipped with a stirrer and a thermometer while stirring the resulting cleaning slurry at 50 ° C. for 60 minutes while stirring at a stirring peripheral speed of 20 m / min. Filtered.

~ Dry ~
The obtained filter cake was dried at 45 ° C. for 48 hours with a forward air dryer and sieved with a mesh having a mesh size of 75 μm to obtain toner base particles a. The toner base particles a were confirmed to be coated with the crosslinked resin fine particles D1 by observing a thin film slice of the toner particles with a TEM.

~ External treatment ~
To 100 parts by mass of toner base particles a, 0.6 parts by mass of hydrophobic silica having an average particle size of 100 nm, 1.0 part by mass of titanium oxide having an average particle size of 20 nm, and hydrophobic silica fine powder having an average particle size of 15 nm 0.8 part of the body was mixed with a Henschel mixer to obtain toner a.

-Fabrication of carrier-
To 100 parts by mass of toluene, 100 parts by mass of a silicone resin (organostraight silicone), 5 parts by mass of γ- (2-aminoethyl) aminopropyltrimethoxysilane, and 10 parts by mass of carbon black are added and dispersed for 20 minutes with a homomixer. To prepare a resin layer coating solution. Using a fluid bed type coating apparatus, the resin layer coating solution was applied to the surface of 1000 parts by mass of spherical magnetite having an average particle size of 50 μm to prepare a carrier.

-Production of developer-
Using a ball mill, 5 parts by mass of each toner and 95 parts by mass of the carrier were mixed to prepare a developer. Next, various properties were evaluated using the produced developers as follows. The results are shown in Table 6.

<Low temperature fixability>
As a fixing roller, type 6200 paper (manufactured by Ricoh Co., Ltd.) is set and fixed using an apparatus in which the fixing unit of a copying machine (MF-200, manufactured by Ricoh Co., Ltd.) using a Teflon (registered trademark) roller is modified. A copy test was performed by changing the roller temperature in increments of 5 ° C. The minimum fixing roller temperature at which the residual ratio of the image density after rubbing the fixed image with a pad becomes 70% or more was defined as the minimum fixing temperature.
The fixing lower limit temperature is preferably low because power consumption can be suppressed, and a problem higher than 140 ° C. is likely to occur.
〔Evaluation criteria〕
A: Low temperature fixability is less than 120 ° C. ○: Low temperature fixability is 120 or more and less than 130 Δ: Low temperature fixability is 130 or more and less than 140 ×: Low temperature fixability is 140 ° C. or more

<Heat resistant storage stability>
A 50 ml glass container is filled with toner, left in a thermostatic bath at 50 ° C. for 24 hours, then cooled to 24 ° C., and the penetration is measured by a penetration test (JIS K2235-1991). The heat resistant storage stability was evaluated. It should be noted that the penetration in the present invention refers to a value indicating the depth of penetration in mm, and the greater the penetration, the better the heat resistant storage stability, and the penetration is 4 mm. If it is less than (×), there is a high possibility of problems in use.
〔Evaluation criteria〕
◎: Needle penetration is 10 mm or more ○: Needle penetration is 7 mm or more and less than 10 mm △: Needle penetration is 4 mm or more and less than 7 mm ×: Needle penetration is less than 4 mm

<Measurement of Volume Average Particle Size (Dv) and Ratio (Dv / Dn) of Toner Particles>
The volume average particle diameter (Dv), number average particle diameter (Dn), and ratio (Dv / Dn) of each toner particle were measured using a particle size measuring device (“Multisizer III”, manufactured by Beckman Coulter, Inc.) with an aperture diameter of 100 μm. It measured and analyzed with the analysis software (Beckman Coulter Multisizer3 Version3.51). Specifically, 0.5 mL of 10% by weight surfactant (alkylbenzene sulfonate, Neogen SC-A, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) is added to a 100 ml glass beaker, and 0.5 g of each toner is added. The mixture was stirred with a microspatel, and then 80 ml of ion-exchanged water was added. The obtained dispersion was subjected to a dispersion treatment for 10 minutes with an ultrasonic disperser (W-113MK-II, manufactured by Honda Electronics Co., Ltd.). The dispersion was measured with “Multisizer III” using Isoton III (manufactured by Beckman Coulter, Inc.) as a solution for measurement. The toner sample dispersion was dropped so that the concentration indicated by the apparatus was 8% ± 2%. In this measurement method, it is important that the concentration is 8% ± 2% from the viewpoint of measurement reproducibility of the particle diameter. Within this concentration range, no error occurs in the particle size.

(Example 2)
<Preparation of Toner b>
A toner of Example 2 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C2 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Example 3)
<Preparation of Toner c>
A toner of Example 3 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C3 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

Example 4
<Preparation of Toner d>
A toner of Example 4 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C4 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Example 5)
<Preparation of Toner e>
A toner of Example 5 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C5 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Example 6)
<Preparation of Toner f>
A toner of Example 6 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C6 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Example 7)
<Preparation of Toner g>
A toner of Example 7 was produced in the same manner as in Example 2 except that the crosslinked resin fine particle D1 was replaced with the crosslinked resin fine particle D2 in the preparation of the aqueous medium phase of Example 2.

(Example 8)
<Preparation of Toner h>
A toner of Example 7 was produced in the same manner as in Example 2 except that the crosslinked resin fine particle D1 was replaced with the crosslinked resin fine particle D3 in the preparation of the aqueous medium phase of Example 2.

(Comparative Example 1)
<Preparation of Toner i>
A toner of Comparative Example 1 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C9 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Comparative Example 2)
<Preparation of Toner j>
A toner of Comparative Example 2 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C10 in the preparation of the master batch (MB) and the toner material phase in Example 1. .

(Comparative Example 3)
<Preparation of Toner k>
A toner of Comparative Example 3 was produced in the same manner as in Example 2 except that in the preparation of the toner material phase of Example 2, poly D-lactic acid was replaced with oleic acid amide (Neontron manufactured by Nippon Seika Co., Ltd.). did.

(Comparative Example 4)
<Preparation of Toner l>
A toner of Comparative Example 4 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C7 in the preparation of the master batch (MB) and the toner material phase in Example 1.

(Comparative Example 5)
<Preparation of toner m>
A toner of Comparative Example 5 was produced in the same manner as in Example 1 except that the binder resin C1 was replaced with the binder resin C8 in the preparation of the master batch (MB) and the toner material phase in Example 1.

For the toners obtained in Examples 2 to 8 and Comparative Examples 1 to 5, developers were prepared and evaluated in the same manner as in Example 1. The results are shown in Table 6.
In addition, Table 6 shows the content (% by mass) in the total binder resin of poly L-lactic acid of the toners obtained in Examples 1 to 8 and Comparative Examples 1 to 5.

  As described above, in Examples 1 to 8, toners having excellent low-temperature fixability and heat-resistant storage stability were obtained. In particular, in Example 2, the Tg of the amorphous part of the binder resin is in a preferable range, and the most excellent effect in achieving both low temperature fixability and heat resistant storage stability was confirmed. In Example 1, since the Tg of the amorphous part of the binder resin was high, the low temperature fixability was inferior to that of Example 2. In Example 3, since the Tg of the amorphous part of the binder resin was low, the heat resistant storage stability was inferior to that of Example 2. In Examples 4 to 6, since the optical purity of the poly-L lactic acid part of the binder resin was lower than the preferred range, the heat-resistant storage stability due to crystallization of the poly-L-lactic acid part became insufficient. In Example 7, since the Tg of the crosslinked resin fine particles was low, the crosslinked resin fine particles on the toner surface were easily softened near room temperature, and sufficient heat-resistant storage stability could not be expressed. In Example 8, since the particle diameter of the crosslinked resin fine particles was too large, the binder resin was prevented from melting at the time of toner heat fixing, resulting in poor low temperature fixability. In Comparative Example 3, the organic crystallization nucleating agent elutes into the aqueous medium in the step of forming the toner material such as the binder resin dissolved or dispersed in the organic solvent as the toner particles in the aqueous medium. Thus, the effect of improving the heat resistant storage stability by promoting crystallization cannot be obtained, resulting in a problem in use as a toner. In Comparative Example 4, since the Tg of the amorphous part of the binder resin is too low, even when the toner surface is coated with the crosslinked resin fine particles, the loose agglomerates due to deformation of the toner particles at room temperature occur. The toner was generated and could not be used as a toner. In Comparative Example 5, the Tg of the amorphous part of the binder resin is too high, so that the heat-resistant storage stability is obtained, but the melt viscosity of the binder resin is too high, so the performance that can be used as a low-temperature fixing toner cannot be obtained. It was.

Japanese Patent No. 3344214 Japanese Patent No. 3455523 JP-A-4-179967 Japanese Patent No. 2597452 JP 2006-91278 A JP 2006-285150 A JP 2010-14757 A

Claims (8)

  An electrostatic charge image developing toner comprising toner particles containing a binder resin and a colorant, wherein the binder resin comprises an amorphous polyester having a glass transition point of -20 ° C or higher and 35 ° C or lower, poly L-lactic acid, And a poly L-lactic acid content of 50% by mass to 80% by mass of the total binder resin, and poly L-lactic acid as a crystallization nucleating agent for poly L-lactic acid in the toner particles. A toner for developing electrostatic images, comprising: a crystalline resin of the optical isomer (D-form) and / or an organic compound containing the structure of the optical isomer (D-form) of poly L-lactic acid.   The toner particles include a binder resin containing at least a copolymer of the non-crystalline polyester and poly L-lactic acid, a colorant, and a crystallization nucleating agent of the poly L-lactic acid in an organic solvent. It is obtained by dissolving or dispersing the material, emulsifying or dispersing the oil phase comprising the dissolved or dispersed toner material in an aqueous medium, and removing the organic solvent from the dispersion obtained by granulation. The toner for developing an electrostatic charge image according to claim 1.   The toner particles are coated with fine particles of a crosslinked resin containing a styrene polymer, an acrylate polymer, or a methacrylic ester polymer. The fine particles of the crosslinked resin have a glass transition temperature of 50 to 100 ° C. and a particle size of 10 The toner for developing an electrostatic charge image according to claim 1 or 2, wherein the toner is -500 nm.   The electrostatic image developing toner according to any one of claims 1 to 3, wherein the crystallization nucleating agent is poly-D-lactic acid and / or a copolymer thereof.   The monomer used for the polymerization reaction of the poly-L-lactic acid part of the copolymer of the non-crystalline polyester and poly-L-lactic acid has an optical purity X (%) = | X (L form) -X (in terms of monomer component) D-form) | [where X (L-form) represents the L-form ratio (mol%) in terms of optically active monomer, and X (D-form) represents the D-form ratio (mol%) in terms of optically active monomer)] The electrostatic image developing toner according to claim 1, wherein the toner is 90% or more and 100% or less.   6. The electrostatic charge image according to claim 1, wherein the toner for developing an electrostatic charge image has a volume average particle diameter Dv / number average particle diameter Dn of 1.00 to 1.30. Development toner.   The toner for developing an electrostatic image according to claim 1, wherein the toner particles contain a crystalline polyester resin as a fixing aid.   The method for producing a toner for developing an electrostatic charge image according to any one of claims 1 to 7, wherein the toner material containing a binder resin and a colorant is dissolved or dispersed in at least an organic solvent. A step of emulsifying and dispersing an oil phase composed of a solution or dispersion of the toner material in an aqueous medium and granulating, and an organic solvent removing step of removing the organic solvent, The binder resin contains a copolymer of an amorphous polyester having a glass transition point of −20 ° C. or more and 35 ° C. or less and poly L-lactic acid, and the content of poly L-lactic acid is 50% by mass of the total binder resin. 80% by mass or less, a crystalline resin of an optical isomer of poly L-lactic acid (D-form) and / or an optical isomer of poly-L-lactic acid as a crystallization nucleating agent for poly L-lactic acid in an organic solvent ( An organic compound containing the structure of D-form) Method for producing a toner for developing electrostatic images which is characterized.