JP2015175930A - Toner for electrostatic image development, developer, image forming apparatus, and process cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide toner for electrostatic image development including resin containing polylactic acid as binder resin, configured to solve the problem of colorant which is unlikely to be dispersed in a toner particle, which is specific to the polylactic acid, and to provide developer using the toner, an image forming apparatus, and a process cartridge.SOLUTION: Toner contains resin having a polylactic acid skeleton. Colorant exists in an area inside an area located within 50nm closer to the center from an outer most surface of a base particle of the toner. An area ratio of the colorant in the inside area is 5% or more.

Description

  The present invention relates to an electrostatic image developing toner, a developer, an image forming apparatus, and a process cartridge.

Due to the rise of recent environmentally friendly products, etc., a technology that uses plant-derived raw materials and fixes toner with low energy is desired.
As a means for utilizing a resin using a plant-derived raw material as a toner material, there is an example of using amorphous polylactic acid as a binder resin (for example, Patent Document 1).

Patent Document 2 proposes an electrostatic image developing toner using a modified binder resin made of amorphous polylactic acid. That is, Patent Document 2 discloses a toner using a binder resin obtained by block copolymerizing a segment of a polylactic acid skeleton and a segment of a polyester skeleton other than polylactic acid. As an explanation for the optical isomer ratio X (%) = | X (L isomer) -X (D isomer) | of the L lactic acid and the D lactic acid forming the segment of the polylactic acid skeleton is 80% or less ”, the L isomer Necessary for the production of polymerized toner and improved polymerized toner by preventing the crystallinity of the polylactic acid skeleton from significantly increasing by avoiding that one of the D and D isomers is much larger than the other. It has been disclosed to provide a toner that guarantees solubility in an organic solvent and is excellent in both low-temperature fixability and long-term storage stability (paragraph [0018] et al.).
However, it cannot be said that the technique described in Patent Document 2 is intended to solve the problem that the colorant is unevenly distributed in the case of a toner using polylactic acid.

  When polylactic acid is used, there is a problem that the colorant is unevenly distributed when used as a toner, which affects the low-temperature fixability and color characteristics of the toner.

  The present invention solves the problem that a colorant is difficult to disperse inside toner particles, which is a problem specific to polylactic acid, in a toner for electrostatic image development using a resin containing a polylactic acid component as a binder resin, and It is an object to provide a developer, an image forming apparatus, and a process cartridge using the toner.

As a result of intensive investigations on a polylactic acid-containing binder resin using a colorant, the present inventors have reached the present invention. In other words, in the present invention, although the distinction between the sea and the island is not as clear as the sea-island structure in the conventional toner, it contains a polylactic acid part, but the toner is composed of toner particles containing a binder resin close to the sea-island structure. By creating islands that are different from polylactic acid (exactly the island equivalent part) so that the colorant can easily be present inside the toner particles, the dispersibility of the colorant is improved, and the toner has excellent color characteristics and low-temperature fixability. Can be provided.
This invention is based on the said knowledge by the present inventors, and the means for solving the said subject is as the following (1).
(1) “A toner containing a resin having a polylactic acid skeleton, wherein a colorant is present in a region further inside than a region within 50 nm from the outermost surface of the base particle of the toner toward the center thereof, A toner characterized in that the area ratio of the colorant in the inner region is 5% or more. "

  According to the present invention, it is possible to provide a toner for forming an electrostatic image in which the colorant is well dispersed and has high color characteristics and low-temperature fixability.

It is a figure which shows an example of the dispersion state of a pigment. It is a figure which shows an example of the dispersion state of a pigment. 1 is a schematic configuration diagram illustrating an example of an image forming apparatus of the present invention. It is a schematic block diagram which shows another example of the image forming apparatus of this invention. It is a schematic block diagram which shows another example of the image forming apparatus of this invention. It is the elements on larger scale of FIG. It is a schematic block diagram which shows an example of the process cartridge of this invention.

The present invention relates to the “toner” described in the above (1). The “toner” is described in the following (2) to (9), as will be understood from the following detailed description. The thing of an aspect like this is included. The present invention also relates to “developer”, “process cartridge”, and “image forming apparatus” described in the following (10) to (12).
(2) “The toner according to (1) above, wherein the area ratio of the colorant in the internal region is 10% or more and 30% or less.”
(3) “The toner according to (1) or (2) above, wherein the resin having a polylactic acid skeleton includes a copolymer of a polylactic acid segment and a polyester segment other than polylactic acid.”
(4) “The toner according to any one of (1) to (3) above, wherein the copolymer is a copolymer (A) hardly soluble in ethyl acetate.”
(5) “The toner according to any one of (1) to (4) above, wherein the ratio of the polylactic acid segment in the copolymer (A) is 50 wt% or less.”
(6) The toner according to any one of (1) to (5), wherein the copolymer (A) is a copolymer of an amorphous polyester segment and an amorphous polylactic acid segment. . "
(7) “The resin having the polylactic acid skeleton further contains a copolymer (B) of a crystalline polyester segment and an amorphous polylactic acid segment,” (1) to (6), The toner according to any one. "
(8) “The toner according to any one of (1) to (7) above, wherein the copolymer (B) is a graft copolymer.”
(9) “The toner according to (7) or (8), wherein the content ratio (copolymer (A) / copolymer (B)) is 50/50 to 20/80”.
(10) “A developer comprising the toner according to any one of (1) to (9) above and a carrier.”
(11) “At least a latent electrostatic image bearing member and developing means for developing a latent electrostatic image formed on the latent electrostatic image bearing member with toner to form a visible image, A process cartridge that can be attached to and detached from a forming apparatus main body, wherein the toner is the toner according to any one of (1) to (9).
(12) “An electrostatic latent image carrier, charging means for charging the surface of the electrostatic latent image carrier, and exposure for exposing the surface of the charged electrostatic latent image carrier to form an electrostatic latent image” Developing means for developing the electrostatic latent image with toner to form a visible image, transfer means for transferring the visible image to a recording medium, and a transfer image transferred to the recording medium. An image forming apparatus having at least a fixing unit for fixing, wherein the toner is the toner according to any one of (1) to (9).

Hereinafter, the present invention will be described in detail.
The toner of the present invention includes at least a binder resin and a colorant, and further includes other components as necessary.

<Binder resin>
(Polylactic acid resin and polylactic acid part)
The binder resin used in the toner of the present invention contains a polylactic acid component.
The polylactic acid component used as the binder resin may be polylactic acid alone, a copolymer of polylactic acid and other materials, or a blend of polylactic acid and other resin components. The “other material” in the copolymer or the “other resin content” in the blend is preferably polyester-based (including modified polyester).

A generally known method is used in the production of polylactic acid. For example, polylactic acid aqueous solution can be directly dehydrated and condensed while heating under reduced pressure in the presence of an appropriate catalyst, or by heating, or once polylactic acid of low molecular weight is prepared, this is depolymerized and used as a bicyclic cyclic ester. It can be obtained by a method of ring-opening polymerization of a certain lactide.
Polylactic acid includes optical isomers L-lactic acid and D-lactic acid, but in the present invention, amorphous polylactic acid obtained by combining these into a polymer is preferred. This is because the crystalline polylactic acid, which is originally crystalline, is partially made amorphous in order to heat and melt at a suitable temperature in the heat characteristics required for the toner, that is, in the heat fixing method.
In the present invention, in order to make both the block copolymer A and the block copolymer B, which will be described in detail later, amorphous, it is preferable that the ratio of the L-form to the D-form is about the same. When the ratio of the L-form and the D-form is about the same, a resin having a low glass transition point can be obtained. In order to use the toner as a toner, if the toner does not have a high Tg to some extent, the heat resistant storage stability is affected. Therefore, from the viewpoint of maintaining the heat-resistant storage stability of the toner, it is preferable that either one is excessive, and from the viewpoint of economy, it is more preferable that the amount of D-type lactic acid is small.
However, the partial amorphization of the block copolymer as the binder resin may depend on the type and properties of the resin component of the polylactic acid copolymerization partner.

An appropriate blending ratio is that the glass transition temperature of the resulting resin is 40 ° C. to 62 ° C., more preferably 45 ° C. to 62 ° C., so that the ratio of L-type lactic acid to D-type lactic acid is 48: It is arbitrarily selected within the range of 52 to 95: 5.
Moreover, even if D-type lactic acid is excess, it is the same, and is selected from the range of 48: 52-5: 95. Among these, the range of 80:20 to 95: 5 is more preferable. Polylactic acid is not good in compatibility with other resins because the ester bond site is dominant in the structure.
This tendency remains essentially even when partly amorphous. Therefore, in the present invention, it can be used as a blend with another resin, but it is more preferably used as a chemical conjugate reacted with another resin component.

(Resin material copolymerized with polylactic acid)
[Block copolymer A]
The resin material or precursor to be copolymerized with polylactic acid is not particularly specified, but examples thereof include polyester, polycarbonate, polyether, vinyl resin having a hydroxyl group, silicone resin having a hydroxyl group at the terminal, and precursors thereof. Can be mentioned.
Among these, polyester is preferable, and amorphous polyester and its precursor are more preferable.

In order to disperse the colorant, a constitution in which hydroxycarboxylic acid, particularly an asymmetric carbon atom C ^* -containing hydroxycarboxylic acid in which a hydroxy group and a carboxy group are bonded to one carbon atom, is dehydrated and condensed as a binder resin. It is desirable to use a block copolymer (A) of amorphous polyester and polylactic acid that does not contain a repeating unit. The block copolymer (A) can be obtained by a conventionally known method, but a lactide ring-opening method is preferable from the viewpoint of productivity, and a batch type or a continuous type is not limited. Preferably, lactide is subjected to ring-opening polymerization using amorphous polyester as a starting material to form a binder resin. The weight ratio of the block copolymer (A) in the binder resin can be 10 wt% or more and 100, but is preferably 15 wt% or more and 97 wt% or less. It is preferably 15 wt% or more from the viewpoint of pigment dispersion and 80 wt% or less from the viewpoint of fixing width or storage stability.
The content of the amorphous polyester in the block copolymer (A) is preferably 30 wt% or more, and more preferably 50 wt% or more and 80 wt% or less from the dispersibility of the colorant and the affinity with polylactic acid.
There is no restriction | limiting in particular as said amorphous polyester content, According to the objective, it can select suitably, For example, the polycondensation polyester synthesize | combined from a polyol and polycarboxylic acid, its intermediate body (precursor), etc. Is mentioned.

There is no restriction | limiting in particular as said amorphous polyester, According to the objective, it can select suitably. Amorphous polyesters can be broadly classified into non-linear (branched or star-type non-aromatic main chain) polyesters, and linear polyesters containing aromatic moieties. Can be mentioned. The polyester having a star-type non-aromatic main chain can be synthesized by adding a tri- or higher functional polyol or polycarboxylic acid as a raw material.
Non-aromatic bulk segment structure of non-linear polyester content not only contributes to amorphization for low temperature fixability but also affinity between various polymers and copolymers containing polylactic acid content It seems to contribute to the transformation. That is, the amorphous polyester component is a block copolymer (B) containing a toner physical property adjusting function, the amorphous polyester containing the aromatic moiety, and a crystalline polyester component to be described in detail later. It is also expected to have a favorable effect such as improving compatibility with.
In addition, the linear polyester resin component containing an aromatic moiety increases the bulk structure of the main chain and contributes to improving the heat-resistant storage stability of the toner, as well as remarkably reducing the polarity in the binder resin, It seems to be effective for improving the dispersibility of
However, this is merely an example, and it is a matter of course that others may have a non-aromatic branched chain and a star structure. Of course, those having an aromatic moiety derived from a polyol such as polyalkylene oxide-added bisphenol A are of course preferable.

  The amorphous polyester resin component can be an unmodified polyester and a modified polyester such as urethane (and / or urea) modified polyester, and such a modified polyester will be understood from the following description. Thus, it has a number of preferable points such as improved heat-resistant storage stability.

Among these, an amorphous polyester resin having a divalent aliphatic alcohol component and a polyvalent aromatic carboxylic acid component as constituent components is particularly preferable.
Examples of the polyol include divalent diols, trivalent to octavalent or higher polyols.

There is no restriction | limiting in particular as said divalent diol, According to the objective, it can select suitably. Examples thereof include aliphatic alcohols (divalent aliphatic alcohols) such as linear aliphatic alcohols and branched aliphatic alcohols. Among these, an aliphatic alcohol having 2 to 36 chain carbon atoms is preferable, and a linear aliphatic alcohol having 2 to 36 chain carbon atoms is more preferable.
These may be used individually by 1 type and may use 2 or more types together.

  The linear aliphatic alcohol is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentane Diol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol and the like. Among these, considering availability, ethylene glycol, 1,3-propanediol (propylene glycol), 1,4-butanediol, 1,6-hexanediol, 1,9-nonanediol, 1,10-decane Diols are preferred. Among these, a linear aliphatic alcohol having 2 to 36 chain carbon atoms is preferable.

Examples of the polycarboxylic acid include dicarboxylic acids, trivalent to hexavalent or higher polycarboxylic acids. Of these, polyvalent aromatic carboxylic acids are preferred.
There is no restriction | limiting in particular as said dicarboxylic acid, According to the objective, it can select suitably, For example, aliphatic dicarboxylic acid, aromatic dicarboxylic acid, etc. are mentioned. Examples of the aliphatic dicarboxylic acid include linear aliphatic dicarboxylic acid and branched aliphatic dicarboxylic acid. Among these, linear aliphatic dicarboxylic acid is preferable.
There is no restriction | limiting in particular as said aliphatic dicarboxylic acid, According to the objective, it can select suitably, For example, alkane dicarboxylic acid, alkenyl succinic acid, alkene dicarboxylic acid, alicyclic dicarboxylic acid etc. are mentioned.

  Examples of the alkanedicarboxylic acid include alkanedicarboxylic acid having 4 to 36 carbon atoms. Examples of the alkanedicarboxylic acid having 4 to 36 carbon atoms include succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, and decylsuccinic acid.

Examples of the alkenyl succinic acid include dodecenyl succinic acid, pentadecenyl succinic acid, and octadecenyl succinic acid.
Examples of the alkene dicarboxylic acid include alkene dicarboxylic acids having 4 to 36 carbon atoms. Examples of the alkene dicarboxylic acid having 4 to 36 carbon atoms include maleic acid, fumaric acid, and citraconic acid.

  As said alicyclic dicarboxylic acid, a C6-C40 alicyclic dicarboxylic acid etc. are mentioned, for example. Examples of the alicyclic dicarboxylic acid having 6 to 40 carbon atoms include dimer acid (dimerized linoleic acid).

  There is no restriction | limiting in particular as said aromatic dicarboxylic acid, According to the objective, it can select suitably, For example, C8-36 aromatic dicarboxylic acid etc. are mentioned. Examples of the aromatic dicarboxylic acid having 8 to 36 carbon atoms include phthalic acid, isophthalic acid, terephthalic acid, t-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-biphenyldicarboxylic acid. It is done.

Examples of the trivalent to hexavalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms. Examples of the aromatic polycarboxylic acid having 9 to 20 carbon atoms include trimellitic acid and pyromellitic acid.
In addition, as the dicarboxylic acid or the trivalent to hexavalent or higher polycarboxylic acid, the above acid anhydrides or alkyl esters having 1 to 4 carbon atoms may be used. Examples of the alkyl ester having 1 to 4 carbon atoms include methyl ester, ethyl ester, and isopropyl ester.

  In order to disperse the colorant, the amorphous polyester is preferably hardly soluble in ethyl acetate. Note that the transmittance of light having a wavelength of 500 nm at an optical path length of 1 cm after leaving a mixture of 100 parts by mass of ethyl acetate and 40 parts by mass of a colorant-dispersing resin at 50 ° C. for 12 hours is less than 20%. In contrast, it is defined as being sparingly soluble.

  The solubility in ethyl acetate can be controlled by adjusting the molecular weight, symmetry of the monomer skeleton, steric hindrance, and the like. If the symmetry of the monomer skeleton is lowered or the steric hindrance is increased, the solubility of the colorant-dispersed resin in ethyl acetate can be improved.

  When the colorant is difficult to disperse in the toner, it is more preferable that the block copolymer (A) is hardly soluble in ethyl acetate.

[Block copolymer B]
From the viewpoint of low-temperature fixability, the main component is preferably a block copolymer (B) of crystalline polyester and polylactic acid. The block copolymer (B) is a ring-opening polymerization of lactide using the crystalline polyester as an initiator. Thus, a binder resin is preferable.
Here, whether or not the polyester is crystalline can be confirmed by evaluation of the melting point by differential scanning calorimetry (DSC measurement), relative crystallinity by wide-angle X-ray diffraction, and the like. However, in order to measure the Bragg angle (2θ ± 2 °) in the X-ray diffraction spectrum (XD), X-rays having a plurality of parallel optical paths (usually, X-rays using Cu and Kα rays as the radiation source) ) Is required to be a crystal having a size that is large enough to be irradiated while maintaining a parallel state, and in the present invention, by differential scanning calorimetry (DSC measurement). evaluated.

There is no restriction | limiting in particular as said crystalline polyester resin, According to the objective, it can select suitably. Examples thereof include polycondensation polyester resins synthesized from polyols and polycarboxylic acids, lactone ring-opening polymers, and ω, ω′-type polyhydroxycarboxylic acids.
There is no restriction | limiting in particular as said crystalline polyester resin, Although it can select suitably according to the objective, The crystalline polyester which has a bivalent aliphatic alcohol component and a bivalent aliphatic carboxylic acid component as a structural component Resins are preferred.

Examples of the polyol include divalent diols, trivalent to octavalent or higher polyols.
The divalent diol is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include aliphatic alcohols such as linear aliphatic alcohols and branched aliphatic alcohols (divalent aliphatic alcohols). ), An alkylene ether glycol having 4 to 36 carbon atoms, an alicyclic diol having 4 to 36 carbon atoms, an alkylene oxide of the alicyclic diol (hereinafter, “alkylene oxide” may be abbreviated as “AO”), Examples thereof include AO adducts of bisphenols, polylactone diols, polybutadiene diols, diols having carboxyl groups, diols having sulfonic acid groups or sulfamic acid groups, and diols having other functional groups such as salts thereof. Among these, an aliphatic alcohol having 2 to 36 chain carbon atoms is preferable, and a linear aliphatic alcohol having 2 to 36 chain carbon atoms is more 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 content with respect to the whole diol of the said linear aliphatic alcohol, Although it can select suitably according to the objective, 80 mol% or more is preferable and 90 mol% or more is more preferable. When the content is 80 mol% or more, the crystallinity of the resin is improved, the compatibility between the low temperature fixability and the heat resistant storage stability is good, and the resin hardness tends to be improved.

  The linear aliphatic alcohol is not particularly limited and may be appropriately selected depending on the intended purpose. For example, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentane Diol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, 1,20-eicosanediol and the like. Among these, ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, 1,10 are preferred because the crystalline polyester resin has high crystallinity and excellent sharp melt properties. Particularly preferred are -decanediol and 1,12-dodecanediol.

  The branched aliphatic alcohol is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably a branched aliphatic alcohol having 2 to 36 chain carbon atoms. Examples of the branched aliphatic alcohol include 1,2-propylene glycol, neopentyl glycol, 2,2-diethyl-1,3-propanediol, and the like.

The alkylene ether glycol having 4 to 36 carbon atoms is not particularly limited and may be appropriately selected depending on the intended purpose. For example, diethylene glycol, triethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene Ether glycol etc. are mentioned.
The alicyclic diol having 4 to 36 carbon atoms is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include 1,4-cyclohexanedimethanol and hydrogenated bisphenol A.

  The trivalent to octavalent or higher polyol is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the trivalent to octavalent or higher polyvalent fat having 3 to 36 carbon atoms. Alcohol; AO adduct of trisphenol (addition mole number 2-30); AO adduct of novolak resin (addition mole number 2-30); Copolymerization of hydroxyethyl (meth) acrylate with other vinyl monomers Examples include acrylic polyols such as products.

Examples of the trivalent to octavalent or higher polyhydric aliphatic alcohol having 3 to 36 carbon atoms include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, sorbitol, sorbitan, and polyglycerin.
Among these, trivalent to octavalent or higher polyhydric aliphatic alcohols and novolak resin AO adducts are preferred, and novolak resin AO adducts are more preferred.

Examples of the polycarboxylic acid include dicarboxylic acids, trivalent to hexavalent or higher polycarboxylic acids.
There is no restriction | limiting in particular as said dicarboxylic acid, According to the objective, it can select suitably, For example, aliphatic dicarboxylic acid (divalent aliphatic carboxylic acid), aromatic dicarboxylic acid, etc. are mentioned. Examples of the aliphatic dicarboxylic acid include linear aliphatic dicarboxylic acid and branched aliphatic dicarboxylic acid. Among these, linear aliphatic dicarboxylic acid is preferable.

There is no restriction | limiting in particular as said aliphatic dicarboxylic acid, According to the objective, it can select suitably, For example, alkane dicarboxylic acid, alkenyl succinic acid, alkene dicarboxylic acid, alicyclic dicarboxylic acid etc. are mentioned.
Examples of the alkanedicarboxylic acid include alkanedicarboxylic acid having 4 to 36 carbon atoms. Examples of the alkanedicarboxylic acid having 4 to 36 carbon atoms include succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanedicarboxylic acid, octadecanedicarboxylic acid, and decylsuccinic acid.

Examples of the alkenyl succinic acid include dodecenyl succinic acid, pentadecenyl succinic acid, and octadecenyl succinic acid.
Examples of the alkene dicarboxylic acid include alkene dicarboxylic acids having 4 to 36 carbon atoms. Examples of the alkene dicarboxylic acid having 4 to 36 carbon atoms include maleic acid, fumaric acid, and citraconic acid.

  As said alicyclic dicarboxylic acid, a C6-C40 alicyclic dicarboxylic acid etc. are mentioned, for example. Examples of the alicyclic dicarboxylic acid having 6 to 40 carbon atoms include dimer acid (dimerized linoleic acid).

  There is no restriction | limiting in particular as said aromatic dicarboxylic acid, According to the objective, it can select suitably, For example, C8-36 aromatic dicarboxylic acid etc. are mentioned. Examples of the aromatic dicarboxylic acid having 8 to 36 carbon atoms include phthalic acid, isophthalic acid, terephthalic acid, t-butylisophthalic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-biphenyldicarboxylic acid. It is done.

Examples of the trivalent to hexavalent or higher polycarboxylic acid include aromatic polycarboxylic acids having 9 to 20 carbon atoms. Examples of the aromatic polycarboxylic acid having 9 to 20 carbon atoms include trimellitic acid and pyromellitic acid.
In addition, as the dicarboxylic acid or the trivalent to hexavalent or higher polycarboxylic acid, the above acid anhydrides or alkyl esters having 1 to 4 carbon atoms may be used. Examples of the alkyl ester having 1 to 4 carbon atoms include methyl ester, ethyl ester, and isopropyl ester.

  Among the dicarboxylic acids, the aliphatic dicarboxylic acid is preferably used alone, and adipic acid, sebacic acid, dodecanedicarboxylic acid, terephthalic acid, or isophthalic acid is more preferably used alone. Also preferred are those obtained by copolymerizing the aromatic dicarboxylic acid together with the aliphatic dicarboxylic acid. As the aromatic dicarboxylic acid to be copolymerized, terephthalic acid, isophthalic acid, t-butylisophthalic acid, and alkyl esters of these aromatic dicarboxylic acids are preferable. Examples of the alkyl ester include methyl ester, ethyl ester, isopropyl ester, and the like. The copolymerization amount of the aromatic dicarboxylic acid is preferably 20 mol% or less.

[Crystalline Polyester C]
Since crystalline polyester has crystallinity, it exhibits a rapid heat melting property near the fixing start temperature. It is more preferable to use the crystalline polyester (C) having such characteristics together with the block copolymer (B). Until the melting start temperature, the blocking resistance due to crystallinity is maintained, and at the melting start temperature, the viscosity of the crystalline polyester (C) is drastically lowered, which becomes a trigger for the melt deformation of the toner and is heated-compressed. Thus, a toner that fills the gaps between the binder resins and has both good blocking resistance and low-temperature fixability can be obtained.

The crystalline polyester (C) is preferably not simply blended with the block copolymer (B), but the finely divided dispersion of (C) is dispersed in (B). When blended simply, (C) tends to be unevenly distributed in the toner, and the quality is not stable.
The L-form and D-form ratio of the polylactic acid part in the block copolymer preferably satisfies L-form / D-form = 70/30 to 90/10. That is, the polylactic acid part is preferably amorphous.
When the L-form ratio is 90/10 or less, the crystallinity of the polylactic acid part is not increased and the low-temperature fixability is not impaired, and a necessary fixing temperature range can be obtained. In addition, workability is not deteriorated, productivity is not deteriorated, and cost is not increased. On the other hand, if the L-form ratio is 70/30 or more, it will not be difficult to handle due to thermal expansion, and the cost will not be increased by using many D-forms with a small abundance ratio. The racemic degree of the polylactic acid part is basically guaranteed, but the ratio can be confirmed by a known method such as pyrolysis GC / MS with a chiral column connected if necessary.

As crystalline polyester C, it was excellent to have a structural unit derived from a saturated aliphatic dicarboxylic acid having 4 to 12 carbon atoms and a structural unit derived from a saturated aliphatic diol having 2 to 12 carbon atoms. This is preferable in that it can exhibit low-temperature fixability.
There is no restriction | limiting in particular in melting | fusing point of this crystalline polyester, Although it can select suitably according to the objective, 50-80 degreeC is preferable. When the melting point is less than 50 ° C., the crystalline polyester is easily melted at a low temperature, and the blocking resistance of the toner may be lowered. On the other hand, when the melting point exceeds 80 ° C., the crystalline polyester (B) is not sufficiently melted by heating at the time of fixing, and the low-temperature fixability may be lowered.
The melting point can be measured by an endothermic peak value of a DSC chart in a differential scanning calorimeter (DSC) measurement.

  Furthermore, the block copolymer B preferably contains a portion composed of a carbodiimide compound in the range of 0.3 to 3% by weight. This is very important in suppressing the hydrolyzability of the polylactic acid part. If it is less than 0.3% by weight, the effect of blocking the carboxyl group and hydroxyl group produced by the initial acid value reduction and decomposition is not exhibited.

<Colorant>
As the colorant used in the toner of the present invention, known dyes, pigments and the like for the toner can be appropriately used. Specifically, carbon black, iron black, Sudan black SM, first yellow G, benzidine yellow, solvent yellow (21, 77, 114, etc.), pigment yellow (12, 14, 17, 83, etc.), Indian first orange, Irgasin Red, Paranitaniline Red, Toluidine Red, Solvent Red (17, 49, 128, 5, 13, 22, 48, 2 etc.), Disperse Red, Carmine FB, Pigment Orange R, Lake Red 2G, Rhodamine FB, Rhodamine B lake, methyl violet B lake, phthalocyanine blue, solvent blue (25, 94, 60, 15.3, etc.), pigment blue, brilliant green, phthalocyanine green, oil yellow GG, Kayaset YG, o Tetrazole brown B and oil pink OP, and the like. These may be used alone or in admixture of two or more.

Further, if necessary, magnetic powder (a powder of a ferromagnetic metal such as iron, cobalt, nickel, or a compound such as magnetite, hematite, ferrite) can also be included as a colorant.
The content of the colorant is preferably 0.1 to 40 parts, more preferably 0.5 to 10 parts, based on weight, with respect to 100 parts of the toner binder of the present invention. In addition, when using magnetic powder, Preferably it is 20-150 parts, More preferably, it is 40-120 parts.

<Release agent>
As the release agent used in the toner of the present invention, those having a softening point of 50 to 170 ° C. are preferable, polyolefin wax, natural wax (for example, carnauba wax, montan wax, paraffin wax and rice wax), carbon number 30 -50 aliphatic alcohols (for example, triacontanol), fatty acids having 30 to 50 carbon atoms (for example, triacontane carboxylic acid), and mixtures thereof.

  Examples of the polyolefin wax include (co) polymers [obtained by (co) polymerization of olefins such as ethylene, propylene, 1-butene, isobutylene, 1-hexene, 1-dodecene, 1-octadecene, and mixtures thereof. And olefin (co) polymer oxides with oxygen and / or ozone, maleic acid modifications of olefin (co) polymers [eg maleic acid and its derivatives (anhydrous Modified products with maleic acid, monomethyl maleate, monobutyl maleate, dimethyl maleate, etc.)], olefins and unsaturated carboxylic acids [(meth) acrylic acid, itaconic acid, maleic anhydride, etc.] and / or unsaturated carboxylic acid alkyls Ester [alkyl (meth) acrylate (alkyl having 1 to 1 carbon atoms) ) Ester, alkyl maleate (alkyl 1 to 18 carbon ester), etc.], polymethylene (eg, Fischer-Tropsch wax such as sazol wax), fatty acid metal salt (eg calcium stearate), fatty acid And esters (such as behenyl behenate).

  As the thermal characteristics of the toner of the present invention, the amount of TMA (thermomechanical analysis) compression deformation (TMA%) at 50 ° C. under a relative humidity of 90% is preferably 10% or less, more preferably 7%. It is as follows. If the TMA% exceeds 10%, it can be easily deformed when summer transportation or sea transportation is assumed. Even if it is excellent, storage stability may be poor under dynamic conditions including error factors. In other words, blocking resistance deteriorates, and in consideration of summer transportation, warehouse storage, temperature in the copying machine, etc., toner may easily stick together, resulting in deterioration of transportability and transferability, resulting in poor image quality. .

  The toner of the present invention may contain various additives such as a charge control agent and a fluidizing agent, if necessary, in addition to the above-described components.

  As charge control agents, nigrosine dyes, triphenylmethane dyes containing tertiary amines as side chains, quaternary ammonium salts, polyamine resins, imidazole derivatives, quaternary ammonium base-containing polymers, metal-containing azo dyes, copper phthalocyanine dyes , Salicylic acid metal salts, boron complexes of benzylic acid, sulfonic acid group-containing polymers, fluorine-containing polymers, halogen-substituted aromatic ring-containing polymers, metal complexes of salicylic acid alkyl derivatives, cetyltrimethylammonium bromide, and the like.

  As a fluidizing agent, colloidal silica, alumina powder, titanium oxide powder, calcium carbonate powder, barium titanate, magnesium titanate, calcium titanate, strontium titanate, zinc oxide, silica sand, clay, mica, wollastonite, Examples thereof include diatomaceous earth, chromium oxide, cerium oxide, bengara, antimony trioxide, magnesium oxide, zirconium oxide, barium sulfate, and barium carbonate.

The composition ratio (% by weight) of each component in the toner is preferably 30 to 97%, more preferably 40 to 95%, and particularly preferably 45 to 92% of the binder resin with the total toner as 100% by weight. Colorant is preferably 0.05 to 60%, more preferably 0.1 to 55%, particularly preferably 0.5 to 50%; mold release agent is preferably 0.1 to 30%, and more preferably 0.5 to 20%, particularly preferably 1 to 10%; the charge control agent is preferably 0 to 20%, more preferably 0.1 to 10%, particularly preferably 0.5 to 7.5%; The fluidizing agent is preferably 0 to 10%, more preferably 0 to 5%, particularly preferably 0.1 to 4%.
The total content of additives is preferably 3 to 70%, more preferably 4 to 58%, and particularly preferably 5 to 50%.
When the composition ratio is within the above range, a toner having good chargeability can be easily obtained.
The volume average particle size of the toner is preferably 3 to 15 μm.

<Toner production method>
The toner of the present invention can be obtained by a conventionally known method such as a kneading and pulverizing method, an emulsion phase inversion method, or a polymerization method. For example, when the kneading pulverization method is adopted, the components of the toner excluding the fluidizing agent are dry-blended, and then melt-kneaded, coarsely pulverized, atomized using a jet mill pulverizer, etc., and further classified to obtain a volume. What is necessary is just to mix a fluidizing agent after making it into microparticles | fine-particles whose average particle diameter (D50) is about 5-20 micrometers. The volume average particle diameter (D50) can be measured using a Coulter counter [for example, trade name: Multisizer III (manufactured by Coulter)].

In the case of employing the emulsion phase inversion method, the constituent components of the toner excluding the fluidizing agent may be dissolved or dispersed in an organic solvent, and then emulsified by adding water, and then separated and classified.
Moreover, you may employ | adopt the method using the organic fine particle as described in Unexamined-Japanese-Patent No. 2002-284881.

  Of the toner manufacturing methods, a method for forming toner base particles will be described in detail.

-Preparation of aqueous medium (aqueous phase)-
The aqueous medium can be prepared, for example, by dispersing resin particles in an aqueous medium. There is no restriction | limiting in particular in the addition amount in the aqueous medium of a resin particle, Although it can select suitably according to the objective, 0.5 to 10 weight% is preferable.
There is no restriction | limiting in particular as an aqueous medium, Although it can select suitably according to the objective, For example, water, a solvent miscible with water, these mixtures, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, water is preferable.

  There is no restriction | limiting in particular as a solvent miscible with water, According to the objective, it can select suitably, For example, alcohol, dimethylformamide, tetrahydrofuran, cellosolves, lower ketones etc. are mentioned. There is no restriction | limiting in particular as said alcohol, According to the objective, it can select suitably, For example, methanol, isopropanol, ethylene glycol, etc. are mentioned. There is no restriction | limiting in particular as said lower ketone, According to the objective, it can select suitably, For example, acetone, methyl ethyl ketone, etc. are mentioned.

-Preparation of oil phase-
The oil phase may be prepared by dissolving or dispersing a toner material containing a block copolymer (A), a crystalline polyester (B), a release agent, a colorant and the like in an organic solvent.
There is no restriction | limiting in particular as an organic solvent, Although it can select suitably according to the objective, The organic solvent whose boiling point is less than 150 degreeC is preferable at the point which is easy to remove.
The organic solvent having a boiling point of less than 150 ° C. is not particularly limited and may be appropriately selected depending on the intended purpose. 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. These may be used individually by 1 type and may use 2 or more types together.
Among these, ethyl acetate, toluene, xylene, benzene, methylene chloride, 1,2-dichloroethane, chloroform, carbon tetrachloride and the like are preferable, and ethyl acetate is more preferable.

-Emulsification or dispersion-
Emulsification or dispersion can be performed by dispersing an oil phase containing the toner material in the aqueous medium. The method for stably forming the dispersion is not particularly limited and may be appropriately selected depending on the purpose. For example, an oil phase prepared by dissolving or dispersing a toner material in a solvent in an aqueous medium phase is added. And a method of dispersing by shearing force.
The disperser for the dispersion is not particularly limited and can be appropriately selected according to the purpose. For example, a low-speed shear disperser, a high-speed shear disperser, a friction disperser, a high-pressure jet disperser, And an ultrasonic disperser. Among these, a high-speed shearing type disperser is preferable in that the particle size of the dispersion (oil droplets) can be controlled to 2 to 20 μm.
When the high-speed shearing disperser is used, conditions such as the number of rotations, the dispersion time, and the dispersion temperature can be appropriately selected according to the purpose.
There is no restriction | limiting in particular in the said rotation speed, Although it can select suitably according to the objective, 1,000-30,000 rpm is preferable and 5,000-20,000 rpm is more preferable.
There is no restriction | limiting in particular in the said dispersion | distribution time, Although it can select suitably according to the objective, In the case of a batch system, 0.1 to 5 minutes are preferable.
There is no restriction | limiting in particular in the said dispersion temperature, Although it can select suitably according to the objective, 0 to 150 degreeC is preferable under pressure.

The amount of the aqueous medium used for emulsifying or dispersing the toner material is not particularly limited and may be appropriately selected depending on the intended purpose, but is 50 to 2,000 parts by weight with respect to 100 parts by weight of the toner material. Preferably, 100 to 1,000 parts by weight are more preferable.
When the amount of the aqueous medium used is less than 50 parts by weight, the dispersion state of the toner material may be deteriorated and toner mother particles having a predetermined particle diameter may not be obtained. When the amount exceeds 2,000 parts by weight, the production cost is increased. May be high.

When emulsifying or dispersing the oil phase containing the toner material, it is preferable to use a dispersant from the viewpoint of stabilizing the dispersion such as oil droplets to obtain a desired shape and sharpening the particle size distribution. .
There is no restriction | limiting in particular as said dispersing agent, According to the objective, it can select suitably, For example, surfactant, a sparingly water-soluble inorganic compound dispersing agent, a polymeric protective colloid, etc. are mentioned.
These may be used individually by 1 type and may use 2 or more types together.
Among these, surfactants are preferable.

The surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, or the like may be used. it can.
There is no restriction | limiting in particular as said anionic surfactant, According to the objective, it can select suitably, For example, alkylbenzene sulfonate, (alpha) -olefin sulfonate, phosphate ester, etc. are mentioned.

-Removal of organic solvent-
The method for removing the organic solvent from the dispersion such as the emulsified slurry is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the temperature of the entire reaction system is gradually raised, Examples thereof include a method of evaporating the organic solvent, a method of spraying the dispersion liquid in a dry atmosphere, and removing the organic solvent in the oil droplets.

  When the organic solvent is removed, toner base particles are formed. The toner base particles can be washed, dried, etc., and further classified. The classification may be performed by removing fine particle portions in a liquid by a cyclone, a decanter, centrifugation, or the like, or may be performed after drying.

The obtained toner base particles may be mixed with particles such as an external additive and a charge control agent. At this time, by applying a mechanical impact force, particles such as external additives can be prevented from being detached from the surface of the toner base particles.
The method for applying the mechanical impact force is not particularly limited and may be appropriately selected depending on the purpose.For example, a method for applying an impact force to a mixture using a blade rotating at high speed, Examples include a method in which a mixture is charged and accelerated to cause particles or particles to collide with an appropriate collision plate.
The apparatus used in the above method is not particularly limited and can be appropriately selected according to the purpose. For example, an ong mill (manufactured by Hosokawa Micron) or an I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) And a hybridization system (manufactured by Nara Machinery Co., Ltd.), a kryptron system (manufactured by Kawasaki Heavy Industries, Ltd.), and an automatic mortar.

<Developer>
The developer of the present invention contains at least the toner and, if necessary, other components such as a carrier as appropriate.
As a result, it is possible to stably form a high-quality image having excellent transferability and chargeability.
The developer may be a one-component developer or a two-component developer. However, when used in a high-speed printer or the like corresponding to the recent improvement in information processing speed, the lifetime is improved. Therefore, a two-component developer is preferable.

  When the developer is used as a one-component developer, there is little fluctuation in the toner particle diameter even if the balance of the toner is performed, and the filming of the toner on the developing roller, or a member such as a blade for thinning the toner Therefore, good and stable developability and images can be obtained even with long-term stirring in the developing device.

When the developer is used as a two-component developer, there is little fluctuation in the toner particle diameter even if the toner balance is maintained over a long period of time, and good and stable developability and image even with long-term stirring in the developing device. Is obtained.
When used as a two-component developer, the toner of the present invention and a carrier are mixed and used.
There is no restriction | limiting in particular in content of a carrier, Although it can select suitably according to the objective, 90 to 98 weight% is preferable and 93 to 97 weight% is more preferable.

-Career-
There is no restriction | limiting in particular as a carrier, Although it can select suitably according to the objective, What has a core material and the resin layer which coat | covers a core material is preferable.

−Core material−
There is no restriction | limiting in particular as a material of a core material, According to the objective, it can select suitably, For example, 50-90 emu / g manganese-strontium type material, manganese-magnesium type material, etc. are mentioned. In order to ensure the image density, it is preferable to use a highly magnetized material such as iron powder of 100 emu / g or more and magnetite of 75 to 120 emu / g. In addition, it is preferable to use a low-magnetization material such as 30-80 emu / g of copper-zinc system because it can reduce the impact of the developer in a spiked state on the photoconductor and is advantageous for high image quality. .
These may be used individually by 1 type and may use 2 or more types together.
There is no restriction | limiting in particular in the volume average particle diameter of a core material, Although it can select suitably according to the objective, 10-150 micrometers is preferable and 40-100 micrometers is more preferable. If the volume average particle diameter is less than 10 μm, fine particles are increased in the carrier, and the magnetization per particle may be reduced to cause carrier scattering. On the other hand, if the thickness exceeds 150 μm, the specific surface area may decrease and toner scattering may occur, and in the case of a full color with many solid portions, reproduction of the solid portions may be particularly poor.

<Image forming apparatus and image forming method>
The image forming apparatus using the toner of the present invention has at least an electrostatic latent image carrier, a charging unit, an exposure unit, a developing unit, a transfer unit, and a fixing unit, and further, as necessary. Have other means.
The developing unit is a unit that develops an electrostatic latent image using toner to form a visible image.

A color image forming apparatus 100 shown in FIG. 3 includes a photosensitive drum 10 (hereinafter also referred to as “photosensitive body 10”) as the electrostatic latent image carrier.
Further, the charging roller 20 as the charging means, the exposure device 30 as the exposure means, the developing device 40 as the developing means, the intermediate transfer member 50, and the cleaning device 60 as the cleaning means having a cleaning blade. And a static elimination lamp 70 as the static elimination means.

The intermediate transfer member 50 is an endless belt, and is designed to be movable in the direction of an arrow by three rollers 51 that are arranged inside and stretched. Part of the three rollers 51 also functions as a transfer bias roller that can apply a predetermined transfer bias (primary transfer bias) to the intermediate transfer member 50. A cleaning device 90 having a cleaning blade is disposed in the vicinity of the intermediate transfer member 50. Also, in the vicinity of the intermediate transfer member 50, there is a transfer roller 80 as the transfer means capable of applying a transfer bias for transferring (secondary transfer) a developed image (toner image) onto a transfer sheet 95 as a recording medium. The intermediate transfer member 50 is disposed opposite to the intermediate transfer member 50.
Around the intermediate transfer member 50, a corona charger 58 for applying a charge to the toner image on the intermediate transfer member 50 is arranged between the photosensitive member 10 and the intermediate transfer member 50 in the rotation direction of the intermediate transfer member 50. It is disposed between the contact portion and the contact portion between the intermediate transfer member 50 and the transfer paper 95.

  The developing device 40 includes a developing belt 41 as the developer carrying member, and a black developing unit 45K, a yellow developing unit 45Y, a magenta developing unit 45M, and a cyan developing unit 45C provided around the developing belt 41. . The black developing unit 45K includes a developer accommodating portion 42K, a developer supply roller 43K, and a developing roller 44K. The yellow developing unit 45Y includes a developer container 42Y, a developer supply roller 43Y, and a developing roller 44Y. The magenta developing unit 45M includes a developer container 42M, a developer supply roller 43M, and a developing roller 44M. The cyan developing unit 45C includes a developer container 42C, a developer supply roller 43C, and a developing roller 44C. Further, the developing belt 41 is an endless belt, is rotatably stretched around a plurality of belt rollers, and a part thereof is in contact with the electrostatic latent image carrier 10.

  In the color image forming apparatus 100 shown in FIG. 3, for example, the charging roller 20 charges the photosensitive drum 10 uniformly. The exposure device 30 performs imagewise exposure on the photosensitive drum 10 to form an electrostatic latent image. The electrostatic latent image formed on the photosensitive drum 10 is developed by supplying toner from the developing device 40 to form a toner image. The toner image is transferred (primary transfer) onto the intermediate transfer member 50 by the voltage applied from the roller 51 and further transferred (secondary transfer) onto the transfer paper 95. As a result, a transfer image is formed on the transfer paper 95. The residual toner on the photoconductor 10 is removed by the cleaning device 60, and the charge on the photoconductor 10 is temporarily removed by the charge eliminating lamp 70.

  FIG. 4 shows another example of the image forming apparatus of the present invention. In the image forming apparatus 100B, the black developing unit 45K, the yellow developing unit 45Y, the magenta developing unit 45M, and the cyan developing unit 45C are arranged directly facing each other around the photosensitive drum 10 without providing the developing belt 41. Other than that, the configuration is the same as that of the image forming apparatus 100 shown in FIG.

FIG. 5 is a schematic diagram showing an example of a two-component developing device using a two-component developer composed of toner and a magnetic carrier.
The image forming apparatus includes a copying apparatus main body 150, a paper feed table 200, a scanner 300, and an automatic document feeder (ADF) 400.

The copying apparatus main body 150 is provided with an endless belt-like intermediate transfer member 50 at the center.
The intermediate transfer member 50 is stretched around the support rollers 14, 15 and 16, and can be rotated clockwise in FIG. 5. In the vicinity of the support roller 15, an intermediate transfer member cleaning unit 17 for removing residual toner on the intermediate transfer member 50 is disposed. A tandem in which four image forming units 18 of yellow, cyan, magenta, and black are arranged to face each other on the intermediate transfer member 50 stretched between the support roller 14 and the support roller 15 along the conveyance direction. A mold developing device 120 is disposed. An exposure unit 21 is disposed in the vicinity of the tandem developing device 120. On the opposite side of the intermediate transfer member 50 from the side where the tandem developing device 120 is arranged, the secondary transfer unit 22 is arranged.
In the secondary transfer unit 22, a secondary transfer belt 24, which is an endless belt, is stretched around a pair of rollers 23, and the recording medium conveyed on the secondary transfer belt 24 and the intermediate transfer member 50 are in contact with each other. Is possible. A fixing unit 25 is disposed in the vicinity of the secondary transfer unit 22.
The fixing unit 25 includes a fixing belt 26 that is an endless belt, and a pressure roller 27 that is pressed against the fixing belt 26.
In the image forming apparatus, a reversing device 28 for reversing the recording medium in order to form an image on both sides of the recording medium is disposed in the vicinity of the secondary transfer unit 22 and the fixing unit 25.

Next, a full color image forming method using the tandem type developing device 120 will be described.
That is, first, a document is set on the document table 130 of the automatic document feeder (ADF) 400, or the automatic document feeder 400 is opened and the document is set on the contact glass 32 of the scanner 300. 400 is closed.
When a start switch (not shown) is pressed, when the document is set on the automatic document feeder 400, the document is transported and moved onto the contact glass 32, and then the document is set on the contact glass 32. When this happens, the scanner 300 is immediately driven, and the first traveling body 33 and the second traveling body 34 travel.
At this time, the light from the light source is irradiated by the first traveling body 33, and the reflected light from the document surface is reflected by the mirror in the second traveling body 34, and is received by the reading sensor 36 through the imaging lens 35 and is received by the color document. A (color image) is read and used as black, yellow, magenta, and cyan image information.
The black, yellow, magenta, and cyan image information is transmitted to each image forming unit 18 in the tandem developing device 120, and black, yellow, magenta, and cyan toner images are formed in each image forming unit. Is done.

  That is, each image forming unit 18 in the tandem developing device 120 uniformly charges the electrostatic latent image carrier 10 (photosensitive member) and the electrostatic latent image carrier as shown in FIG. The electrostatic latent image carrier is exposed (L in FIG. 6) to each color image corresponding to the charger 160 and each color image information, and each color image is formed on the electrostatic latent image carrier. An exposure device for forming a corresponding electrostatic latent image, and developing the electrostatic latent image with each color toner (black toner, yellow toner, magenta toner, and cyan toner) to form a toner image with each color toner A developing device 61, a primary transfer device 62 for transferring the toner image onto the intermediate transfer member 50, a cleaning means 63, and a charge eliminating device 64. Monochromatic image Click image, a yellow image can be formed magenta image, and cyan image).

The black image, the yellow image, the magenta image, and the cyan image formed in this way are formed on the photoreceptor 10 of each color on the intermediate transfer member 50 that is rotated by the support rollers 14, 15, and 16. The transferred images are sequentially transferred (primary transfer).
Then, the black image, the yellow image, the magenta image, and the cyan image are superimposed on the intermediate transfer member 50 to form a composite color image (color transfer image).

On the other hand, in the paper feed table 200, one of the paper feed rollers 142 is selectively rotated to feed the recording medium from one of the paper feed cassettes 144 provided in multiple stages in the paper bank 143, and one sheet at a time by the separation roller 145. The paper is separated and sent to the paper feed path 146, transported by the transport roller 147, guided to the paper feed path 148 in the copying machine main body 150, and abutted against the registration roller 49 to stop.
Alternatively, the sheet feed roller 142 is rotated to feed out sheets (recording paper) on the manual feed tray 54, separated one by one by the separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped. . The registration roller 49 is generally used while being grounded, but may be used in a state where a bias is applied to remove paper dust from the recording medium.
Then, the registration roller 49 is rotated in time with the synthesized color image (color transfer image) synthesized on the intermediate transfer member 50, and the recording medium is sent between the intermediate transfer member 50 and the secondary transfer device 22. Then, by transferring (secondary transfer) the composite color image (color transfer image) onto the recording medium by the secondary transfer device 22, a color image is transferred and formed on the recording medium. The residual toner on the intermediate transfer member 50 after image transfer is cleaned by the intermediate transfer member cleaning device 17.

  The recording medium on which the color image has been transferred is conveyed by the secondary transfer means 22 and sent to the fixing means 25, where the combined color image (color transfer image) is generated by heat and pressure. Is fixed on the recording medium. After that, the recording medium is switched by the switching claw 55 and discharged by the discharge roller 56 and stacked on the paper discharge tray 57. Alternatively, the recording medium is switched by the switching claw 55 and reversed by the reversing device 28 and led again to the transfer position. After the image is also recorded on the back surface, the image is discharged by the discharge roller 56 and stacked on the discharge tray 57.

FIG. 7 shows an example of a process cartridge according to the present invention.
The process cartridge 110 includes a photosensitive drum 10, a corona charger 58, a developing device 40, a transfer roller 80, and a cleaning device 90.
In the present invention, the above-described components can be integrally combined as a process cartridge, and the process cartridge can be configured to be detachable from a main body of an image forming apparatus such as a copying machine or a printer.

  Hereinafter, the present invention will be described in more detail based on examples, but these examples are for the purpose of facilitating understanding of the present invention and are not intended to limit the present invention. In the description of the examples, “part” and “%” represent “part by mass” and “% by mass” unless otherwise specified.

[Production Example 1; Synthesis of amorphous polyester a1]
Propylene glycol and 1,3-propanediol as propylene glycol / 1,3-propanediol = 80/20 (into a 5 L four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple) The molar ratio (OH / COOH) of OH group (OH group of diol) and COOH group (COOH group of terephthalic acid) is 1.2. In this way, 300 ppm of titanium tetraisopropoxide is charged with respect to the mass of the charged raw material, the methanol is allowed to react while flowing out, the temperature is finally raised to 230 ° C., and the resin acid value becomes 5 mgKOH / g or less. The reaction was continued until Then, it was made to react under reduced pressure of 20 mmHg-30mmHg for 4 hours, and amorphous polyester a1 which is a linear polyester resin was obtained.

[Production Example 2: Synthesis of amorphous polyester a2]
In a reaction vessel equipped with a condenser, a stirrer and a nitrogen inlet tube, 187.5 parts of neopentyl alcohol, 79.3 parts of ethylene oxide, 438.6 parts of terephthalic acid, and 0.21 part of tetrabutoxytitanate as a condensation catalyst The mixture was reacted at 180 ° C. for 8 hours while distilling off the methanol produced under a nitrogen stream. Next, the temperature was gradually raised to 230 ° C. and reacted for 4 hours while distilling off generated methanol under a nitrogen stream, and then reacted under reduced pressure of 5 to 20 mmHg until the weight average molecular weight reached 7460. Amorphous polyester a2 having a transition temperature of 68 ° C. was obtained.

[Production Example 3; Synthesis of amorphous polyester a3]
In a reaction vessel equipped with a cooling pipe, a stirrer and a nitrogen introducing pipe, 187.5 parts of neopentyl alcohol, 79.3 parts of ethylene oxide, 199.4 parts of terephthalic acid, 239.2 parts of isophthalic acid and a condensation catalyst 0.21 part of tetrabutoxy titanate was added, and the reaction was carried out at 180 ° C. for 8 hours while distilling off the methanol produced under a nitrogen stream. Next, the temperature was gradually raised to 230 ° C. and reacted for 4 hours while distilling off the methanol produced under a nitrogen stream, and then reacted under reduced pressure of 5 to 20 mmHg until the weight average molecular weight reached 5800. An amorphous polyester a3 having a transition temperature of 52 ° C. was obtained.
The characteristics of these amorphous polyesters are summarized in the following table.

[Production Example 4; Synthesis of crystalline polyester b1]
1,5-hexanediol and adipic acid were charged at a ratio of OH / COOH = 1.15 into a 5 L four-necked flask equipped with a heat-dried nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, A crystalline polyester b1 was obtained by reacting with 300 ppm of titanium tetraisopropoxide under normal pressure at 200 to 230 ° C. for 10 hours and further reacting under reduced pressure of 10 mmHg or less for 5 hours. The melting point of this resin was 55 ° C.

[Production Example 5: Synthesis of polylactic acid P]
In a 500 mL four-necked separable flask, L-lactide 255 g, D-lactide 45 g (weight ratio: L-form / D-form = 85/15) and 1.8 g of ethylene glycol were added, and 40 ° C. for 5 hours. After drying, the internal temperature was gradually raised to 150 ° C., and after confirming that the system had been homogenized by visual observation, 50 mg of tin 2-ethylhexanoate was added to cause a polymerization reaction. 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, the system was cooled to 175 ° C., switched to the outflow line again, delactideed under conditions of 10 mmHg for 60 minutes, and the polymerization reaction was completed to obtain polylactic acid P. The weight average molecular weight (Mw) of this resin was 25000.

[Production Example 6; Synthesis of block copolymer A1]
In a 500 mL four-necked separable flask, 212 g of L-lactide, 38 g of D-lactide (L-form / D-form = 85/15 by weight), and 250 g of amorphous polyester a1 were added, and the mixture was stirred at 40 ° C. for 5 g. After drying for a period of time, the internal temperature was gradually raised to 150 ° C., and after confirming that the system had been homogenized by visual observation, 50 mg of tin 2-ethylhexanoate was added to cause a polymerization reaction. 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 passed, the system was cooled to 175 ° C., switched to the outflow line again, delactideed under conditions of 10 mmHg for 60 minutes, and the polymerization reaction was completed to obtain a block copolymer A1.

[Production Example 7; Synthesis of block copolymer A2]
In a 500-mL four-necked separable flask, 212 g of L-lactide, 38 g of D-lactide (L-form / D-form = 85/15 by weight) and 250 g of amorphous polyester a2 were added, and 5 g at 40 ° C. After drying for a period of time, the internal temperature was gradually raised to 150 ° C., and after confirming that the system had been homogenized by visual observation, 50 mg of tin 2-ethylhexanoate was added to cause a polymerization reaction. 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, the system was cooled to 175 ° C., switched to the outflow line again, delactideed under conditions of 10 mmHg for 60 minutes, and the polymerization reaction was completed to obtain a block copolymer A2.

[Production Example 8: Synthesis of block copolymer A3]
In a 500 mL four-necked separable flask, 375 g of L-lactide 106 g, D-lactide 19 g (L-form / D-form = 85/15 by mass ratio) and amorphous polyester a2 were added, and the mixture was stirred at 40 ° C. for 5 g. After drying for a period of time, the internal temperature was gradually raised to 150 ° C., and after confirming that the system had been homogenized by visual observation, 50 mg of tin 2-ethylhexanoate was added to cause a polymerization reaction. 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, the system was cooled to 175 ° C., switched to the outflow line again, delactideed under conditions of 10 mmHg for 60 minutes, and the polymerization reaction was completed to obtain a block copolymer A3.

[Production Example 9: Synthesis of block copolymer A4]
Block copolymer A4 was obtained by using a3 instead of a2 in Production Example.
The characteristics of these block copolymers A are summarized in the following table.

[Production Example 10; Production of block copolymer B1]
In a 500 mL four-neck separable flask, 212 g of L-lactide, 38 g of D-lactide (L-form / D-form by weight ratio = 85/15), and 107 g of crystalline polyester b1 were charged, and at 40 ° C. for 5 hours. After drying, the internal temperature was gradually raised to 150 ° C., and after confirming that the system had been homogenized by visual observation, 50 mg of tin 2-ethylhexanoate was added to cause a polymerization reaction. 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, the system was cooled to 175 ° C., switched to the outflow line again, delactideed for 60 minutes under the condition of 10 mmHg, and the polymerization reaction was completed to obtain a block copolymer B1.
This resin had a weight average molecular weight (Mw) of 31,000 and a melting point of 51 ° C.

<Preparation of colorant master batch E>
[Production Example 11; Production of colorant master batch E1]
After 18 parts of cyan pigment (CI Pigment blue 15: 3), 82 parts of block copolymer A1 and 15 parts of ion-exchanged water were mixed, an open roll kneader Kneadex (Mitsui Mining Co., Ltd.) was used. And kneaded to obtain a master batch of pigment.
Specifically, kneading started from 100 ° C., and the mixture was gradually cooled to 50 ° C.

[Production Example 12; Production of colorant master batch E2]
A colorant master batch E2 was obtained in the same manner except that A1 in Production Example 9 was replaced with A2.

[Production Example 13; Production of colorant master batch E3]
A colorant master batch E3 was obtained in the same manner except that A1 in Production Example 9 was replaced with A3.

[Production Example 14; Production of colorant master batch E4]
A colorant master batch E4 was obtained in the same manner as in Production Example 9 except that A1 was replaced with A4.

[Production Example 15; Production of colorant master batch E5]
100 parts of block copolymer B1, 100 parts of cyan pigment (CI Pigment blue 15: 3), and 30 parts of ion-exchanged water are mixed well, and an open roll kneader (NIDEX, Nippon Coke Kogyo Co., Ltd.) Kneading was performed using The kneading temperature started kneading from 90 ° C., and then gradually cooled to 50 ° C. to prepare a colorant master batch E5 having a resin to pigment ratio (mass ratio) of 1: 1.

[Production Example 16; Production of colorant master batch E6]
100 parts of polylactic acid P, 100 parts of cyan pigment (CI Pigment blue 15: 3) and 30 parts of ion-exchanged water are mixed well, and an open roll type kneader (NIDEX, manufactured by Nihon Coke Industries Co., Ltd.) ) Was used for kneading. The kneading temperature started kneading from 90 ° C., and then gradually cooled to 50 ° C. to prepare a colorant master batch E6 having a resin to pigment ratio (mass ratio) of 1: 1.
These master batches E are summarized in the following table.

[Production Example 17; Production of wax dispersion]
In a reaction vessel equipped with a condenser, a thermometer and a stirrer, 20 parts of paraffin wax (HNP-9 (melting point: 75 ° C.), manufactured by Nippon Seiwa Co., Ltd.) and 80 parts of ethyl acetate are placed and heated to 78 ° C. The solution was sufficiently dissolved and cooled to 30 ° C. with stirring for 1 hour, and further with an Ultra Visco Mill (manufactured by Imex), the liquid feeding speed was 1.0 kg / hour, the disk peripheral speed was 10 m / second, the diameter Wet pulverization was performed under the conditions of 80% by volume of 0.5 mm zirconia beads and 6 passes, and ethyl acetate was added to adjust the solid content concentration to produce a [wax dispersion] having a solid content concentration of 20%.

Example 1 Production of Toner 1 and Production of Developer 1
(Manufacture of toner 1)
In a container equipped with a thermometer and a stirrer, 70 parts of block copolymer B1 and 57 parts of ethyl acetate were placed, and then heated to a temperature equal to or higher than the melting point of block copolymer B1 and dissolved. Next, after adding 25 parts of the wax dispersion, 36 parts of the colorant master batch E1 and 36 parts of ethyl acetate, the mixture is stirred using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Obtained.
In a vessel equipped with a stirrer and a thermometer, 90 parts of ion-exchanged water, 3 parts of a 5% by weight aqueous solution of polyoxyethylene lauryl ether type nonionic surfactant NL450 (Daiichi Kogyo Seiyaku Co., Ltd.) and 10 parts of ethyl acetate After stirring, an aqueous medium was obtained.
After adding 50 parts of the first liquid to the aqueous medium, the mixture was stirred for 1 minute at 13000 rpm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.) to obtain a second liquid.
The second liquid was put in a container equipped with a stirrer and a thermometer, and then the solvent was removed for 1 hour to obtain a slurry.
100 parts of the slurry was filtered under reduced pressure. Next, 100 parts of ion-exchanged water was added to the filter cake, and the mixture was stirred for 5 minutes at 6000 rpm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.), followed by filtration. Furthermore, 100 parts of a 10% by mass aqueous sodium hydroxide solution was added to the filter cake, and the mixture was stirred for 10 minutes at 6000 rpm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.), followed by filtration under reduced pressure. Next, 100 parts of 10% by mass hydrochloric acid was added to the filter cake, and the mixture was stirred for 5 minutes at 6000 rpm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.), followed by filtration. Furthermore, 300 parts of ion-exchanged water was added to the filter cake, and after stirring for 5 minutes at 6000 rpm using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.), the operation of filtering was repeated twice.
The filter cake was dried at 45 ° C. for 48 hours using a circulating dryer, and then sieved with a mesh having an opening of 75 μm to obtain base particles.
Using a Henschel mixer, 100 parts of base particles and 1 part of hydrophobic silica HDK-2000 (manufactured by Wacker Chemie) were mixed to obtain toner 1.

(Manufacture of carrier 1)
As a core material, 5,000 parts of Mn ferrite particles (weight average diameter: 35 μm) were used.
As a coating material, 300 parts of toluene, 300 parts of butyl cellosolve, acrylic resin solution (composition ratio (molar ratio)) methacrylic acid: methyl methacrylate: 2-hydroxyethyl acrylate = 5: 9: 3, solid content 50% toluene solution, Tg 38 ° C. ) 60 parts, 15 parts of N-tetramethoxymethylbenzoguanamine resin solution (polymerization degree 1.5, solid content 77% toluene solution) and 15 parts of alumina particles (average primary particle size 0.30 μm) were dispersed with a stirrer for 10 minutes. The coating solution prepared in the above was used.
The core material and the coating liquid are charged into a coating apparatus that performs coating while forming a swirling flow provided with a rotating bottom plate disk and a stirring blade in a fluidized bed, and the coating liquid is placed on the core material. Applied. The obtained coated material was baked in an electric furnace at 220 ° C. for 2 hours to obtain [Carrier 1].

(Manufacture of developer 1)
[Carrier 1] 7 parts of [Toner 1] per 100 parts using a type of tumbler mixer (made by Willy et Bacofen (WAB)) in which the container rolls and stirs for 5 minutes at 48 rpm. Uniform mixing was performed to obtain [Developer 1] which is a two-component developer.
The tandem image forming apparatus image shown in FIG. 5 of the indirect transfer method adopting the contact charging method, the two-component developing method, the secondary transfer method, the blade cleaning method, and the external heating roller fixing method for the produced two-component developer. The development unit was loaded to form an image, and the following performance evaluation was performed. The results are shown in Table 4.

Example 2 Production of Toner 2 and Production of Developer 2
In the same manner as in Example 1, the colorant master batch E1 was changed to E2, and a toner 2 was obtained. Further, toner 2 was used in place of toner 1, and developer 2 was obtained in the same manner as in Example 1.
Using the produced developer 2, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

Example 3 Production of Toner 3 and Production of Developer 3
In the same manner as in Example 1, the colorant master batch E1 was changed to E3 to obtain a toner 3. Further, a toner 3 was used in place of the toner 1, and a developer 3 was obtained in the same manner as in Example 1.
Using the prepared developer 3, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

Example 4 Production of Toner 4 and Production of Developer 4
In the same manner as in Example 1, toner 4 was obtained by changing the block copolymer B1 to P. Further, a toner 4 was used in place of the toner 1, and a developer 4 was obtained in the same manner as in Example 1.
Using the produced developer 4, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Example 5: Production of toner 5 and production of developer 5]
In a container equipped with a thermometer and a stirrer, 50 parts of block copolymer B1, 20 parts of block copolymer A2 and 90 parts of ethyl acetate are added, and then the temperature is raised to a temperature equal to or higher than the melting point of block copolymer B1. Warm to dissolve. Next, after adding 25 parts of the wax dispersion, 36 parts of the colorant master batch E1 and 36 parts of ethyl acetate, the mixture is stirred using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Obtained.
Thereafter, toner 5 and developer 5 were obtained in the same manner as in Example 1. Using the produced developer 5, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Example 6: Production of toner 6 and production of developer 6]
In a container equipped with a thermometer and a stirrer, 40 parts of block copolymer B1 and 72 parts of ethyl acetate were placed, and then heated to a temperature equal to or higher than the melting point of block copolymer B1 and dissolved. Next, 25 parts of the wax dispersion, 60 parts of the colorant master batch E1 and 30 parts of ethyl acetate were added, followed by stirring using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Obtained.
Thereafter, toner 6 and developer 6 were obtained in the same manner as in Example 1. Using the produced developer 6, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Example 7: Production of toner 7 and production of developer 7]
In a vessel equipped with a thermometer and a stirrer, 65 parts of block copolymer B1, 5 parts of crystalline polyester and 70 parts of ethyl acetate are added, and the temperature is raised to a temperature equal to or higher than the melting point of block copolymer B1. Warm to dissolve. Next, after adding 25 parts of a wax dispersion, 30 parts of a colorant master batch E1 and 36 parts of ethyl acetate, the mixture is stirred using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Obtained.
Thereafter, toner 7 and developer 7 were obtained in the same manner as in Example 1. Using the produced developer 7, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Comparative Example 1; Production of Toner 8 and Production of Developer 8]
In the same manner as in Example 1, the colorant master batch E1 was changed to E4 to obtain a toner 8.
Further, a toner 8 was used in place of the toner 1, and a developer 8 was obtained in the same manner as in Example 1.
Using the produced developer 8, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Comparative Example 2: Production of toner 9 and production of developer 9]
In a container equipped with a thermometer and a stirrer, 94 parts of the block copolymer B1 and ethyl acetate part were placed, and then heated to a temperature equal to or higher than the melting point of the block copolymer B1 and dissolved. Next, 25 parts of a wax dispersion, 12 parts of a colorant master batch E5 and 30 parts of ethyl acetate were added, followed by stirring using a TK homomixer (manufactured by Tokushu Kika Co., Ltd.). Obtained.
Thereafter, toner 9 and developer 9 were obtained in the same manner as in Example 1.
Using the produced developer 9, an image was formed in the same manner as in Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

[Comparative Example 3; Production of Toner 10 and Production of Developer 10]
In the same manner as in Comparative Example 1, the colorant master batch E4 was changed to E6 to obtain a toner 10.
Further, a toner 10 was used in place of the toner 8, and a developer 10 was obtained in the same manner as in Comparative Example 1.
Using the produced developer 10, an image was formed in the same manner as in Comparative Example 1, and the following performance evaluation was performed. The results are shown in Table 4.

(Measurement of molecular weight)
-Device: GPC (manufactured by Tosoh Corporation), detector: RI, measurement temperature: 40 ° C
-Mobile phase: tetrahydrofuran, flow rate: 0.45 mL / min.
The number average molecular weight Mn, the weight average molecular weight Mw, and the molecular weight distribution Mw / Mn were measured by GPC (gel permeation chromatography) using a calibration curve created from a polystyrene sample with a known molecular weight as a standard.

(Measurement of melting point)
About 5.0 mg of the target sample was placed in an aluminum sample container, and the sample container was placed on a holder unit and set in an electric furnace. Then, it heated from 40 degreeC to 150 degreeC with the temperature increase rate of 10 degree-C / min in nitrogen atmosphere. Thereafter, the sample is cooled from 150 ° C. to −60 ° C. at a temperature decrease rate of 10 ° C./min, and further heated to 150 ° C. at a temperature increase rate of 10 ° C./min, and a differential scanning calorimeter ([Q-2000], TA Instruments Inc. DSC curve was measured using
From the obtained DSC curve, using the analysis program in the system, the DSC curve at the second temperature rise was selected, and the maximum peak temperature (melting point) of the target sample was obtained from the peak top.

<Evaluation>
<< Fixability (Fixing Lower Limit Temperature) >>
Using the image forming apparatus shown in FIG. 5, the toner adhesion amount after transfer is 0.85 ± 0.10 mg / cm ^{2 on} the transfer paper (manufactured by Ricoh Business Expert Co., Ltd., copy printing paper <70>). A solid image of the entire paper (image size 3 cm × 8 cm) is formed, fixing is performed by changing the temperature of the fixing belt, and the surface of the obtained fixed image is drawn using a drawing tester AD-401 (manufactured by Ueshima Seisakusho) A fixing belt that draws with a ruby needle (tip radius 260 μmR to 320 μmR, tip angle 60 degrees), a load of 50 g, and rubs the drawing surface with fibers (Hanicot # 440, manufactured by Hanilon Corporation) 5 times strongly, so that the image is hardly scraped. The temperature was defined as the minimum fixing temperature. Further, the solid image was created on the transfer paper at a position of 3.0 cm from the front end in the paper passing direction. The speed of passing through the nip portion of the fixing device is 280 mm / second. The lower the fixing minimum temperature, the better the low-temperature fixability. Evaluation was made according to the following evaluation criteria.

〔Evaluation criteria〕
A: 110 ° C. or less ○: 110 ° C. or more and 120 ° C. or less Δ: 120 ° C. or more 130 ° C. or less

<Evaluation of pigment dispersibility>
After embedding the toner in an epoxy resin and solidifying it overnight, a section having an average thickness of 80 nm was prepared using an ultra microtome (manufactured by Diatome). Next, the dispersion state of the pigment was observed using a transmission electron microscope H7000 (manufactured by Hitachi, Ltd.). Evaluation was made according to the following evaluation criteria.

〔Evaluation criteria〕
◯: As shown in FIG. 2, the pigment is dispersed inside the toner (whether it is uniform or non-uniform, it is not inside the toner surface but inside).
Δ: The pigment is slightly unevenly distributed on the surface of the toner, but is also dispersed inside the toner.
X: As shown in FIG. 1, most of the pigment is unevenly distributed on the toner surface.

<Pigment area ratio>
The area ratio of the pigment was determined from an image observed with a transmission electron microscope. First, after cutting out only a portion 50 nm inside from the boundary surface between the embedding resin and the toner and binarizing, the area ratio of the pigment portion in the cut out image was obtained. This was measured for 20 toners and the average value was taken. As software for image processing, LM eye of OPTELICS C130 manufactured by Lasertec Corporation was used.
The results are shown in Table 4.

<Color evaluation>
Using a developer, a monochrome image having an area ratio of 20% is output on an A4 size paper (T6000 70W T, manufactured by Ricoh) so that the toner amount is 0.40 mg / cm ^2, and the fixed image is X- Rituation 938 (manufactured by X-Rite Co., Ltd.) Status A mode, chromaticity a * b * was measured with d50 light, and saturation c * was calculated from the square root of the sum of the squares of a * and b *. .

(Toner image pass / fail judgment)
From the evaluation result of the saturation c *, the toner pass / fail judgment was performed as follows.
A: Saturation c * is 60 or more. O: Saturation c * is 55 or more and less than 60. X: Saturation c * is less than 55.

(About Fig. 3 and Fig. 4)
DESCRIPTION OF SYMBOLS 100 Image forming apparatus 100B Image forming apparatus 10 Photoconductor 20 Charging roller 30 Exposure apparatus 40 Developer 41 Developing belt 42C Developer accommodating part 42M Developer accommodating part 42Y Developer accommodating part 42K Developer accommodating part 43C Developer supply roller 43M Developing Agent supply roller 43Y Developer supply roller 43K Developer supply roller 44C Development roller 44M Development roller 44Y Development roller 44K Development roller 45C Cyan development unit 45M Magenta development unit 45Y Yellow development unit 45K Black development unit 50 Intermediate transfer body 51 Roller 58 Corona charging Device 60 Cleaning device 70 Static elimination lamp 80 Transfer roller 90 Cleaning device 95 Transfer paper L Exposure device (about FIG. 5)
10 (K, Y, M, C) Photosensitive drum 14 Support roller 15 Support roller 16 Support roller 17 Intermediate transfer member cleaning unit 18 Image forming unit 21 Exposure unit 22 Secondary transfer unit 23 Roller 24 Secondary transfer belt 25 Fixing unit 26 fixing belt 27 pressure roller 28 reversing device 32 contact glass 33 first traveling body 34 second traveling body 35 imaging lens 36 reading sensor 49 registration roller 50 intermediate transfer body 52 separation roller 53 manual feed path 54 manual feed tray 55 switching Claw 56 Ejection roller 57 Ejection tray 62 Transfer roller 120 Tandem developer 130 Document table 142 Paper feed roller 143 Paper bank 144 Paper feed cassette 145 Separation roller 146 Paper feed path 147 Conveyance roller 148 Paper feed path 150 Copier main body 200 Feed Paper Bull 300 Scanner 400 automatic document feeder (ADF)
(About Figure 6)
DESCRIPTION OF SYMBOLS 10 Electrostatic latent image carrier 18 Image formation means 50 Intermediate transfer body 61 Developing device 62 Primary transfer device 63 Cleaning means 64 Static elimination device 160 Charger L Exposure (about FIG. 7)
DESCRIPTION OF SYMBOLS 110 Process cartridge 10 Photosensitive drum 40 Developing device 58 Corona charger 80 Transfer roller 90 Cleaning device 95 Recording paper L Exposure light

JP 2009-162956 A JP 2008-262179 A

Claims (12)

  A toner comprising a resin having a polylactic acid skeleton, wherein a colorant is present in an inner region further than a region within 50 nm from the outermost surface of the base particle of the toner toward the center thereof, and coloring in the inner region A toner, wherein the area ratio of the agent is 5% or more.   The toner according to claim 1, wherein an area ratio of the colorant in the inner region is 10% or more and 30% or less.   The toner according to claim 1, wherein the resin having a polylactic acid skeleton includes a copolymer of a polylactic acid segment and a polyester segment other than polylactic acid.   The toner according to claim 1, wherein the copolymer is a copolymer (A) that is hardly soluble in ethyl acetate.   5. The toner according to claim 1, wherein a ratio of the polylactic acid segment in the copolymer (A) is 50 wt% or less.   The toner according to any one of claims 1 to 5, wherein the copolymer (A) is a copolymer of an amorphous polyester segment and an amorphous polylactic acid segment.   The toner according to claim 1, further comprising a copolymer (B) of a crystalline polyester segment and an amorphous polylactic acid segment as the resin having a polylactic acid skeleton.   The toner according to claim 1, wherein the copolymer (B) is a graft copolymer.   The toner according to claim 7 or 8, wherein the content ratio (copolymer (A) / copolymer (B)) is 50/50 to 20/80.   A developer comprising the toner according to claim 1 and a carrier.   The image forming apparatus main body includes at least an electrostatic latent image carrier and developing means for developing the electrostatic latent image formed on the electrostatic latent image carrier using toner to form a visible image. A process cartridge that is detachable, wherein the toner is the toner according to claim 1.   An electrostatic latent image carrier, charging means for charging the surface of the electrostatic latent image carrier, exposure means for exposing the charged surface of the electrostatic latent image carrier to form an electrostatic latent image, and Developing means for developing an electrostatic latent image with toner to form a visible image, transferring means for transferring the visible image to a recording medium, and fixing means for fixing the transferred image transferred to the recording medium An image forming apparatus comprising: the toner according to claim 1, wherein the toner is the toner according to claim 1.

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