WO2013147168A1

WO2013147168A1 - Coloring pigment dispersion liquid for toner particles and toner for electrostatic charge image development

Info

Publication number: WO2013147168A1
Application number: PCT/JP2013/059548
Authority: WO
Inventors: 幸恵河津; 克大河原; ノリ子永松; 俊介篠崎; はるな山口
Original assignee: 株式会社Ｄｎｐファインケミカル
Priority date: 2012-03-30
Filing date: 2013-03-29
Publication date: 2013-10-03
Also published as: TW201343805A

Abstract

The problems addressed by the present invention are: to discover a dispersing agent that favorably disperses a coloring pigment in a polymerizable monomer and that maintains favorable dispersion properties and incorporation properties of the coloring pigment in the polymerizable monomer, even in a liquid droplet formation step resulting from the suspension of the polymerizable monomer in an aqueous solvent and an immediately subsequent polymerization step for the polymerizable monomer; to provide a coloring pigment dispersion liquid that is for toner particles and that can produce toner particles having a favorable particle size, particle size distribution, and the like, having a favorable shape, and having the coloring pigment favorably dispersed within the toner; and to provide a toner for electrostatic charge image development using the coloring pigment dispersion liquid for toner particles. The problems are solved by means of a coloring pigment dispersion liquid that is for toner particles, contains a coloring pigment, a dispersing agent, and a polymerizable vinyl-group-containing monomer, and is characterized by the dispersing agent resulting from bonding an organic group having a repeating unit to an isocyanate group of an isocyanurate-ring-containing compound resulting from a diisocyanate trimerizing to form an isocyanurate ring. The problems are further solved by means of a toner that is for electrostatic charge image development, contains suspension polymerized toner particles resulting from the suspension/dispersion in an inorganic colloid aqueous solution of a toner starting material liquid containing at least a thermal polymerization initiator and a coloring pigment dispersion liquid, which results from the dispersion of a coloring pigment in a vinyl-group-containing monomer having a polymerizable double bond in the presence of a dispersing agent, in a manner so that the volume average particle size (Dv) is 2-10 μm inclusive, and then performing thermal polymerization, and that is characterized by the average pigment prevalence, resulting from averaging the pigment prevalence in a cross-section of one particle of the toner for electrostatic charge image development, being at least 0.6.

Description

Colored pigment dispersion for toner particles and toner for developing electrostatic image

The present invention relates to a color pigment dispersion for toner particles, and more specifically, by using a specific dispersant, the dispersibility of the color pigment in the vinyl group-containing monomer is improved, and the vinyl group-containing monomer is dispersed in an aqueous medium. The present invention relates to a color pigment dispersion for toner particles having improved particle stability.
The present invention also relates to a toner for developing an electrostatic image. More specifically, by using a color pigment dispersion for toner particles, the color pigment is uniformly distributed in the toner particles, thereby providing a static color having a good color density. The present invention relates to a charge image developing toner.

The toner used in the electrophotographic system is colored particles containing a coloring pigment and other additives in a binder resin, and is used for developing and visualizing an electrostatic image in a printer, copying machine, etc. It is done. The production methods are roughly classified into (a) a kneading and pulverizing method; (b) a polymerization method such as a suspension polymerization method and an emulsion aggregation method; and (c) a dissolution granulation method.

(A) The kneading and pulverization method is a method in which a binder resin, a color pigment, and the like are dry-mixed, melt-kneaded with a kneader or the like, and then pulverized and classified to produce toner particles.
(B-1) The suspension polymerization method is a method of producing toner particles by suspending and dispersing a polymerizable vinyl group-containing monomer, a polymerization initiator, a color pigment, and the like in an aqueous medium and then polymerizing.
(B-2) In the emulsion aggregation method, the “polymerizable vinyl group-containing monomer” is emulsified and dispersed in an aqueous medium containing a polymerization initiator, an emulsifier, etc., and then polymerized to obtain primary particles, which are then colored. In this method, after adding a pigment or the like, the primary particles are aggregated to produce toner particles.
(C) Dissolution granulation method involves dissolving and dispersing a binder resin, a color pigment, and the like in an organic solvent, dispersing the obtained liquid in an aqueous medium to form droplets, and removing the organic solvent from the droplets. This is a method for producing toner particles by removing the toner particles.

In any production method, the dispersion of the colored pigment is important, and the dispersibility is constantly improved. (A) In the kneading and pulverization method, the colored pigment is dispersed in the molten resin having a high viscosity. Once the colored pigment is dispersed in the molten resin, the toner is crushed after cooling and the colored pigment is dispersed as it is. Particles can be produced.

However, in (b) the polymerization method and (c) the dissolution granulation method, the dispersion of the color pigment is reduced to a “low-viscosity raw material for the binder resin such as a polymerizable monomer”, “a binder resin solvent”, etc. In addition, once the colored pigment is dispersed, preparation of droplets by suspending the colored pigment dispersion in an aqueous medium, polymerization of polymerizable monomers, etc., primary particles In the process of forming toner particles such as agglomeration and granulation, the dispersibility of the color pigment itself deteriorates, or it is suspended, polymerized and agglomerated in an aqueous medium due to the influence of the color pigment and the dispersant for the color pigment. In some cases, toner particle formation such as granulation may be inhibited.

As a result, not only the toner particles in which the color pigment is well dispersed cannot be produced, but also the toner particles having a good shape, particle size, particle size distribution and the like cannot be produced.
In addition, the pigment is not uniformly dispersed in the toner particles, and as a result, when an image is formed on paper or the like with a printer, a copying machine, etc., a sufficient color density can be obtained when the toner adhesion amount is viewed at a constant level. There was no case.

Therefore, in order to improve the dispersibility, Patent Documents 1 to 3 describe (b-1) a dispersant for coloring pigments in the suspension polymerization method, and Patent Document 4 describes (b-1) A surface treatment agent for improving the dispersibility of the colored pigment in the turbid polymerization method is described.
Patent Documents 5 to 8 describe (c) a dispersing agent for a colored pigment in the dissolution granulation method, and Patent Document 9 improves the dispersibility of the colored pigment in the (c) dissolution granulation method. A surface treatment agent is described.

However, the demand for the quality of images by the electrophotographic method has been increasing, and such a known technique has been insufficient.

Japanese Patent Laid-Open No. 03-200976 JP 2002-226727 A JP 2007-094352 A Japanese Patent Laid-Open No. 2004-341084 JP 2005-181835 A JP 2006-293204 A JP 2009-244871 A JP 2010-061040 A Japanese Patent Laid-Open No. 11-231572

As described above, particularly in the suspension polymerization method, even when the color pigment is dispersed in the “polymerizable vinyl group-containing monomer” (hereinafter sometimes abbreviated as “polymerizable monomer”), the subsequent color pigment Dispersibility of the colored pigment into the polymerizable monomer deteriorates in the preparation of the polymerizable monomer droplets by suspending the dispersion in an aqueous medium, polymerization of the polymerizable monomer, and the like. In addition, the suspension of the polymerizable monomer in the aqueous medium may be deteriorated due to the influence of the dispersant for the coloring pigment or the like, or the toner particle formation may be inhibited.

Further, in the suspension polymerization method, due to the formation mechanism of droplets that become suspension polymerization toner particles (hereinafter, sometimes simply referred to as “toner particles”), in the reaction system of the polymerizable monomer, There is a drawback that insoluble substances such as colored pigments can be easily removed out of the system, and there is a problem that the colored pigments do not stay normally in the polymerization monomer droplets during polymerization.

In the dispersant described in the above-described patent document, the state in which the color pigment is completely taken into the polymerizable monomer cannot be maintained in the toner particle forming process such as droplet formation or polymerization.
In particular, since the incorporation efficiency of the colored pigment into the polymerizable monomer is poor at the initial stage of the polymerization reaction, the resulting colored pigment tends to adhere to the vicinity of the surface of the toner particles. Depending on the case, the influence of the surface of the toner particles may appear, and the environmental characteristics in the toner image formation may be deteriorated, or the charge control may be difficult to control.

In addition, when the color pigment is dispersed in the polymerizable monomer, the toner may not be sufficiently concentrated because it is easily aggregated or difficult to be miniaturized. Even when fine dispersion in the polymerizable monomer is possible, if the affinity of the dispersant or the coloring pigment for the aqueous medium is not appropriate, the toner particles may aggregate or the shape of the toner particles may be In some cases, the color density of the resulting toner may decrease.

The present invention has been made in view of the above, and the problem is that a color pigment is well dispersed in a polymerizable monomer, and a droplet forming step is performed by suspending the polymerizable monomer in an aqueous medium, followed by polymerization. Even during the polymerization process of the polymerizable monomer, good dispersibility and incorporation of the color pigment into the polymerizable monomer are maintained, the droplet formation process in the aqueous medium is stabilized, the shape of the toner particles after polymerization, A toner capable of producing toner particles having a good shape, suitable particle size and particle size distribution, etc. by finding a dispersant that maintains a good particle size, particle size distribution, etc. The object is to provide a colored pigment dispersion for particles.
In addition, the problem is that electrostatic image development that contains toner particles in which pigments are uniformly distributed inside, and can obtain a high color density when an image is formed on a medium such as paper with a constant adhesion amount. It is to provide a toner.

As a result of intensive studies to solve the above problems, the present inventor has found that the above problems can be improved by using a dispersant having a specific chemical structure, and the above problems can be solved. The present invention has been completed.
Further, it has been found that the above-mentioned problems can be improved and the above-mentioned problems can be solved by subjecting a toner raw material liquid containing a specific color pigment dispersion to thermal dispersion after being suspended and dispersed in an inorganic colloidal aqueous solution. Thus, the present invention has been completed.

That is, the present invention relates to a color pigment dispersion for toner particles containing a color pigment, a dispersant, and a polymerizable vinyl group-containing monomer, wherein the dispersant is formed by trimerization of diisocyanate and isocyanurate. An object of the present invention is to provide a colored pigment dispersion for toner particles, which is formed by bonding an organic group having a repeating unit to an isocyanate group of an isocyanurate ring-containing compound that forms a ring.

The present invention also provides a method for producing toner particles, characterized in that the color pigment dispersion for toner particles is suspended in an aqueous medium and polymerized.

The present invention also relates to an electrostatic charge image developing toner obtained by using the above-described color pigment dispersion for toner particles, wherein the color pigment has a polymerizable double bond in the presence of a dispersant. The pigment dispersion and the toner raw material liquid containing at least a thermal polymerization initiator are suspended in an inorganic colloidal aqueous solution so that the volume average particle diameter (Dv) is 2 μm or more and 10 μm or less. An electrostatic image developing toner containing suspension-polymerized toner particles that are dispersed and then thermally polymerized, and an average pigment in which the abundance of pigments in the cross section of one particle of the electrostatic image developing toner is averaged The present invention provides a toner for developing an electrostatic image, wherein the abundance ratio is 0.6 or more.

The present invention also relates to a method for producing the above-described toner for developing an electrostatic image, wherein the color pigment is polymerized using beads having a diameter of 0.01 mm or more and 5 mm or less as a dispersion medium in the presence of a dispersant. A colored pigment dispersion is prepared by dispersing in a vinyl group-containing monomer having a double bond, and a toner raw material liquid is prepared by blending at least a thermal polymerization initiator in the colored pigment dispersion. An average comprising a step of suspending and dispersing in an inorganic colloidal aqueous solution so that the volume average particle size (Dv) is 2 μm or more and 10 μm or less, and then thermally polymerizing to produce suspension-polymerized toner particles. The present invention provides a method for producing a toner for developing an electrostatic image having a pigment abundance ratio of 0.6 or more.

According to the present invention, the above-mentioned problems are solved, the above-mentioned problems are solved, the color pigment is well dispersed in the polymerizable monomer, the polymerizable monomer is suspended in the aqueous medium, and the polymerizable monomer is subsequently dispersed. Even during polymerization, it is possible to provide a color pigment dispersion for toner particles that maintains good dispersibility and incorporation of the color pigment into the polymerizable monomer and suppresses the color pigment from appearing on the surface of the toner particles. .

In addition, according to the present invention, the color pigment is well dispersed inside the toner, and the state is maintained during suspension and polymerization, so that the shape, particle size, particle size distribution, etc. of the toner particles are suitably controlled. However, since the toner particles can be produced and the affinity with the aqueous medium is appropriate, the shape of the toner particles can be made spherical.
As a result, a toner having a small amount of coarse powder and fine powder, a sharp particle size distribution, excellent circularity, and a good charge amount can be obtained. A toner image having a high reflection density of the portion can be obtained.

In particular, according to the present invention, when the above-mentioned problems are solved, the toner contains toner particles in which the color pigment is uniformly distributed, and a solid image is formed on a substrate such as paper, a high color density with a constant adhesion amount is obtained. An electrostatic charge image developing toner that can be obtained can be provided.
Further, it is possible to provide a toner for developing an electrostatic charge image that can obtain a sufficient color density with a constant adhesion amount even if the content of the color pigment in the toner particles is small.
In the case of a color toner, when the color density is fixed, the smaller the content of the color pigment in the toner particles, the higher the transparency, so that a clear image is formed. In addition, the amount of the color pigment used is small and the cost can be reduced.

In particular, in the production process of toner particles such as “droplet forming step of polymerizable monomer (suspension step)” and “polymerization monomer polymerization step” in which the color pigment dispersion is suspended in an aqueous medium, Since the dispersibility in the polymerizable monomer is good and the physical properties and compatibility of the color pigment and the dispersant for the color pigment are good, the suspension state of the polymerizable monomer in the aqueous medium does not deteriorate, and the toner particles The above-described effects are exhibited because the conversion is performed well.
In the polymerization reaction system of the polymerizable monomer, even the insoluble coloring pigment is difficult to be excluded from the system, and the above effect is exhibited because the coloring pigment stays normal in the polymerization monomer droplets during the polymerization process. Is done.

Unlike conventional methods, in the process of forming toner particles such as droplet formation and polymerization, it is possible to maintain a state in which the color pigment is uniformly dispersed in the polymerizable monomer, and as a result, a large amount of color pigment is present near the surface of the toner particle. The toner particles are unlikely to exist, the environmental characteristics are good, and the chargeability with which the surface is particularly involved can be easily controlled. In addition, since the color pigment is uniformly dispersed throughout the toner particles, a toner with good color development can be produced.

Further, since the affinity of the pigment dispersion for the aqueous medium is moderate, the toner particles do not aggregate and the shape of the toner particles does not deteriorate. Further, since the affinity of the colored pigment to the aqueous medium is moderate, the colored pigment is uniformly dispersed inside the toner particles, and the color density of the resulting toner is improved.
In particular, the “electrostatic image developing toner characterized in that the average pigment abundance ratio is 0.6 or more” produced using the colored pigment dispersion for toner particles of the present invention has not existed in the past. It is new.

Color pigment dispersion (TEM photograph) in yellow toner particles produced using the color pigment dispersions Y1 and Y2 for toner particles of the present invention and conventional dispersions y1, y2 and y3, and toner particles (SEM photograph, upper magnification of 10000 times, lower magnification of 1000 times, except for Experimental Example A5, upper magnification of 3000 times, lower magnification of 400 times). Color pigment dispersions (TEM photographs) in cyan toner particles and black toner particles produced using the color pigment dispersions C1 and K1 for toner particles of the present invention and the conventional dispersions c1, k1 and k2. 2 is a photograph showing the shape of toner particles (SEM photograph, upper magnification of 10000 times, lower magnification of 1000 times) (where k1 is a lump and there is no photograph). An example of the toner particles of the toner for developing an electrostatic charge image in the present invention is shown, and is a diagram of one of TEM photographs (magnification of 2100 times) used for calculating the pigment abundance ratio (Experimental Example F04). 2 is a TEM photograph of a cross section of toner particles of an electrostatic charge image developing toner obtained in an experimental example.

Hereinafter, the present invention will be described, but the present invention is not limited to the following specific embodiments, and can be arbitrarily modified within the scope of the technical idea.

<Colored pigment dispersion for toner particles>
The present invention relates to a color pigment dispersion for toner particles containing a color pigment, a dispersant, and a “polymerizable vinyl group-containing monomer”.
Here, the “polymerizable vinyl group-containing monomer” (polymerizable monomer) may be one type or a mixture of two or more types, but in the case of one type itself, in the case of two or more types, it is a mixture. It is preferable that the liquid in the state is a liquid at normal temperature (20 ° C.), and the color pigment dispersion for toner particles of the present invention is obtained by dispersing a color pigment in the liquid with a dispersant.

The dispersant has a chemical structure in which an organic group having a repeating unit is bonded to the isocyanate group of “an isocyanurate ring-containing compound formed by diisocyanating trimerization to form an isocyanurate ring”. .
Hereinafter, the parentheses may be simply abbreviated as “ring-containing compound”. In addition, a structure in which the isocyanate group of the ring-containing compound is modified by the reaction of an “organic group having a repeating unit” described later or a linking group thereof may be abbreviated as “ring-containing compound”.
Further, “electrostatic image developing toner” may be simply abbreviated as “toner”.

Such a ring-containing compound is obtained by trimerizing diisocyanate to form an isocyanurate ring, and the number of isocyanurate rings in the ring-containing compound may be one or two or more. However, it is preferable that the number is 2 or more, the dispersibility of the color pigment in the polymerizable monomer, the ability to maintain the dispersibility during suspension or polymerization of the polymerizable monomer, the polymerizable monomer droplets and the toner particles This is preferable in that the shape, particle size, particle size distribution and the like are suitable. Particularly preferred is 2-4.
The ring-containing compound may be one kind or a mixture of two or more kinds. In the case of a mixture, the number of isocyanurate rings in the ring-containing compound is 1.2 to 2.2. 5 is preferable.

When there are two or more isocyanurate rings in the dispersant, the diisocyanate forming the isocyanurate ring may be one type or two or more types.

Examples of the diisocyanate include p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, naphthalene-1,5-diisocyanate and the like; hexamethylene diisocyanate Aliphatic diisocyanates such as lysine methyl ester diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate; alicyclic diisocyanates such as isophorone diisocyanate, 4,4′-methylenebis (cyclohexyl isocyanate); xylylene diisocyanate, etc. And aliphatic diisocyanates having an aromatic ring.

Preferred are diisocyanates having an aromatic ring, hexamethylene diisocyanate, isophorone diisocyanate and the like, and particularly preferred are diisocyanates having an aromatic ring because the dispersibility is improved by interaction with the pigment structure.

That is, the ring-containing compound has at least one isocyanurate ring formed by trimerization of diisocyanate having an aromatic ring, dispersibility of polymerizable pigment in the polymerizable monomer, polymerizable monomer This is preferable in terms of maintaining the dispersibility during suspension and polymerization, the shape of the polymerizable monomer droplets and toner particles, the particle size, the particle size distribution, and the like.

Furthermore, it is preferable from the above point that the isocyanurate ring-containing compound is represented by the following formula (1).

[In the formula (1), R ² represents hydrogen or a branched or unbranched substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, and m represents an integer of 0 or more. ]

In formula (1), R ² represents hydrogen or a branched or unbranched substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms. The hydrocarbon group may be a saturated hydrocarbon group or an unsaturated hydrocarbon group. Specifically, for example, an alkyl group, an alkenyl group, an alkynyl group, a substituted or unsubstituted aryl group, a substituted Alternatively, an unsubstituted heteroaryl group, a substituted or unsubstituted alkaryl group, a substituted or unsubstituted aralkyl group, and the like can be given.
R ² is preferably hydrogen or an unbranched hydrocarbon group having 1 to 12 carbon atoms, particularly preferably a methyl group.
M represents an integer of 0 or more, more preferably 0 to 3, and particularly preferably 1.
When the isocyanurate ring-containing compound represented by the formula (1) is a mixture, the average number of isocyanurate rings in the ring-containing compound in the formula (1) is more preferably 1 to 4. It is particularly preferably 2 to 2.5.

Among them, in Formula (1), R ² is more preferably a methyl group, and R ² is more preferably bonded to the ortho or para position of the isocyanate group substituted on the benzene ring.
That is, the isocyanurate ring-containing compound possessed by the dispersant in the present invention preferably has an isocyanurate ring formed by trimerization of tolylene diisocyanate. Among these, 2,4-tolylene diisocyanate is preferable. It is particularly preferable to have an isocyanurate ring formed by trimerization.

That is, the ring-containing compound (one obtained by dimerizing diisocyanate to form an isocyanurate ring) is specifically represented by the following formula (2) or represented by formula (2). Most preferably, two or more are bonded. The preferred number (m + 1) of bonded isocyanurate rings is the same as described above for m.

The ring-containing compound has an isocyanate group that has not been used for isocyanurate ring formation, but the dispersant in the present invention has a chemical structure in which an “organic group having a repeating unit” is bonded to the remaining isocyanate group. Is.
Although an isocyanate group exists in the ring-containing compound, in order to eliminate the extremely high reactivity of the isocyanate group, it is preferable that all the isocyanate groups are finally modified by being reacted with an organic group. The organic groups reacting with the isocyanate groups need not all be “organic groups having repeating units”, and at least one of them may be “organic groups having repeating units”. Of the organic groups reacting with isocyanate groups, more than half of the organic groups reacting with the isocyanate groups are preferably “organic groups having a repeating unit” from the viewpoint of the property, the shape stability of the polymerizable monomer droplets and toner particles, etc. A “organic group having a repeating unit” is preferable.

Among organic groups that react with isocyanate groups, compounds that react with isocyanate groups to give organic groups that are not the above “organic groups having repeating units” include primary or secondary amino groups, hydroxyl groups, carboxyl groups, and the like. A compound having an active hydrogen-containing group is particularly preferable, and a compound having one active hydrogen-containing group in the molecule is particularly preferable.
A compound having one active hydrogen-containing group in the molecule and reacting with an isocyanate group of the ring-containing compound to give an amine value to the dispersant is particularly preferable.

Further, among compounds that give an "organic group" by reacting with an isocyanate group of a ring-containing compound, compounds that give an organic group that is not "an organic group having a repeating unit" include an active hydrogen-containing group and a tertiary amino group. Compounds (hereinafter abbreviated as “amine value-imparting compounds”) are particularly preferred.
That is, the above-mentioned colored pigment dispersion for toner particles, which is obtained by further combining “the compound having an active hydrogen-containing group and a tertiary amino group” with the isocyanate group of the ring-containing compound, In order to exhibit the effect, it is particularly preferable to disperse the color pigment suitably in the polymerizable monomer and to reduce the particle size of the toner particles and stabilize the particle size distribution and shape.

The tertiary amino group of the amine value-imparting compound includes a tertiary amino group in a nitrogen-containing ring such as a pyridine ring, a quinoline ring, an imidazole ring or a triazole ring; a trialkylamino group such as a trimethylamino group or a triethylamino group; N -N-aryl-N-dialkylamino groups such as phenyl-N-dimethylamino group; tertiary amino groups in N-alkyl nitrogen-containing rings such as N-alkylpyrrole rings and N-alkylimidazole rings; .

Examples of the active hydrogen-containing group possessed by the “amine value-imparting compound” include those described above, and a primary amino group or a hydroxyl group is particularly preferred.

The “amine value-imparting compound” is not limited to those described below, but specifically, N, N-dimethyl-1,2-ethanediamine, N, N-diethyl-1,2-ethane Diamine, N, N-dimethyl-1,3-propanediamine, N, N-diethyl-1,3-propanediamine, N, N-dipropyl-1,3-propanediamine, N, N-dibutyl-1,3 Chain compounds such as propanediamine, N, N-dimethyl-1,4-butanediamine, N, N-diethyl-1,4-butanediamine; 4- (2-aminoethyl) pyridine, 4- (3- Pyridine compounds such as aminopropyl) pyridine; imidazole compounds such as 1- (3-aminopropyl) imidazole, 2-aminoimidazole, 1- (2-aminoethyl) imidazole; 3-amino 1,2,4-triazole, triazole compounds such as 5-amino-1,4-diphenyl-1,2,3-triazole; and the like.

The amine value of the dispersant in the present invention is preferably 0 to 100 mgKOH / g, more preferably 3 to 40 mgKOH / g, particularly preferably 6 to 30 mgKOH / g, and 10 to 20 mgKOH / g. More preferably.
When the amine value is in the above range, the effect of the present invention can be exhibited. In particular, when the amine value is absent or too small, the adsorptivity to the pigment is insufficient and the colored pigment is dispersed in the polymerizable monomer. If the amine value is too large, it is difficult for the color pigment to be taken into the polymerizable monomer, and the color pigment comes out on the surface of the toner particle. The shape, particle size, and particle size distribution of the toner particle Etc. may not be suitably controlled.

The “organic group having a repeating unit” only needs to have a repeating unit somewhere in the organic group, and the repeating unit may react with the isocyanate group of the ring-containing compound via the linking group Y, Although it may react directly with the isocyanate group of the ring-containing compound, it is preferably reacted directly with the isocyanate group.
Examples of the linking group Y include a simple single bond (no linking group), an alkylene group, an arylene group, and an alkenylene group.

At the terminal of the compound that gives the “organic group having a repeating unit” or at the terminal of the linking group, there is a group that reacts with the isocyanate group of the ring-containing compound.
The group of the “organic group having a repeating unit” that reacts with the isocyanate group of the ring-containing compound is not particularly limited, but a group having active hydrogen such as a hydroxyl group or an amino group is preferable.
As will be described later, when the repeating unit is a polyester chain and / or a polyalkylene glycol chain, the “group reactive to an isocyanate group” is a hydroxyl group.

In addition, “an organic group having no repeating unit” R ¹ (hereinafter sometimes abbreviated as “terminal group R ¹ ”) is provided on the side of the “repeating unit” opposite to the side reacting with the isocyanate group. May be present.
The terminal group R ¹ is preferably an alkyl group, more preferably an alkyl group having 1 to 26 carbon atoms, particularly preferably an alkyl group having 2 to 22 carbon atoms, and still more preferably an alkyl group having 2 to 18 carbon atoms.
Further, as described below, the terminal group may be a ring-containing compound. In that case, in the dispersant of the present invention, two or more ring-containing compounds are bonded through “an organic group having a repeating unit”.

The ring-containing compound may be bonded via an “organic group having a repeating unit” bonded to the isocyanate group of the ring-containing compound. That is, the said terminal group is another ring containing compound, and the isocyanate group of this another ring containing compound may couple | bond with the "organic group which has a repeating unit."
For example, in the case where the ring-containing compound is represented by the above formula (1), two ring-containing compounds are bonded via an “organic group having a repeating unit” to thereby form 4 It becomes a dispersant having an isocyanurate ring.

The number of ring-containing compounds in the dispersant of the present invention is preferably 1 to 3, particularly preferably 1 to 2. These may be one kind or a mixture of two or more kinds. For example, if one and two ring-containing compounds are mixed at a molar ratio of 1: 1, the average number of ring-containing compounds in the dispersant is 1.5.
The average number of ring-containing compounds in the dispersant is preferably 1 to 2, particularly preferably 1.2 to 1.8. Therefore, in the case where the ring-containing compound is represented by the above formula (1), the average number of isocyanurate rings in the dispersant is preferably 2 to 4, particularly preferably 2.4 to 3.6.

The “repeating unit” in the “organic group having a repeating unit” is not particularly limited, but is preferably one having “—O—” in the chemical structure in order to control hydrophilicity. An alkylene glycol chain is particularly preferred.
When the repeating unit is a polyester chain and / or a polyalkylene glycol chain, hydrophilicity is imparted to the dispersant, and the dispersibility of the color pigment in the polymerizable monomer is improved by stabilization due to steric hindrance. This is preferable. Further, it is preferable from the viewpoint of stabilizing the droplets by providing a hydrophilic balance during polymerization in an aqueous medium, and stabilizing the shape and particle size distribution during polymerization.

The polyester chain may be formed by a reaction between a diol and a dicarboxylic acid, or may be formed by a ring-opening reaction of a cyclic ester compound.
Further, the polyester chain may be formed by the ring opening of a cyclic ester compound and reaction with a diol and / or dicarboxylic acid.

The diol is preferably an aliphatic diol having 1 to 8 carbon atoms, particularly preferably an alkane diol having 1 to 8 carbon atoms.
As the dicarboxylic acid, a dicarboxylic acid having 1 to 8 carbon atoms is preferable, and an aliphatic dicarboxylic acid having 1 to 8 carbon atoms is particularly preferable.

That is, as the repeating unit which is a polyester chain, those represented by the following formula (S1) are particularly preferable.
— (Z ¹ —O—CO—Z ² —CO—O) _r — (S1)
In the formula (S1), Z ¹ and Z ² each represent an alkylene group having 1 to 8 carbon atoms which may be different from each other, r is preferably 2 to 20, more preferably 3 to 10, and particularly preferably 4 to 8.
The repeating unit is an isocyanate group of the ring-containing compound,
—NH—CO—O— (Z ¹ —O—CO—Z ² —CO—O) _r — (S2)
Join in the form of

The cyclic ester compound is preferably a cyclic ester compound having 2 to 9 carbon atoms, and specifically, β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone and the like are particularly preferable.

As the repeating unit which is a polyester chain, those represented by the following formula (S3) in which ε-caprolactone is ring-opened and polymerized are particularly preferable.
— (CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ —CO—O) _n — (S3)
In the formula (S3), n is preferably 2 to 20, more preferably 3 to 15, and particularly preferably 4 to 10.
The repeating unit is an isocyanate group of the ring-containing compound,
—NH—CO—O— (CH ₂ CH ₂ CH ₂ CH ₂ CH ₂ —CO—O) _n — (S4)
Join in the form of

Further, a polyester chain obtained by reacting the diol while the cyclic ester compound is opened is also particularly preferable.

The number average molecular weight of the polyester chain is not particularly limited, and it may be 100 to 100, regardless of whether the diol and the dicarboxylic acid are reacted with each other, or the cyclic ester compound is opened and reacted. 10,000 is preferable, 150 to 6000 is more preferable, 250 to 4000 is particularly preferable, and 300 to 2000 is still more preferable.

The polyalkylene glycol chain which is a “repeating unit” is preferably a polyethylene glycol chain, a polypropylene glycol chain or the like. The polyalkylene glycol chain imparts hydrophilicity to the dispersant, and improves the dispersibility of the color pigment in the polymerizable monomer by stabilization due to steric hindrance.
Among these, particularly the polypropylene glycol chain can make the hydrophilicity of the dispersant to which it is bound within a particularly preferable range, and in the droplet forming process, the droplet is stabilized, and the shape, particle size, etc. of the toner particle are particularly preferable. Can be.

The number average molecular weight of the polyalkylene glycol chain is not particularly limited, but is preferably 100 to 10,000, more preferably 150 to 6000, particularly preferably 250 to 4000, and further preferably 300 to 2000.

Specifically, those represented by the following formula (S5) or (S6) are particularly preferable.
-(CH ₂ CH ₂ O) _p- (S5)
-(CH (CH ₃ ) CH ₂ O) _q- (S6)
In the formulas (S5) and (S6), p and q are preferably 5 to 200, more preferably 8 to 150, particularly preferably 10 to 100, and still more preferably 12 to 80.
The repeating unit is an isocyanate group of the ring-containing compound,
—NH—CO—O— (CH ₂ CH ₂ O) _p — (S7)
Or
—NH—CO—O— (CH (CH ₃ ) CH ₂ O) _q − (S8)
Join in the form of

The dispersant in the present invention may have both a polyester chain and a polyalkylene glycol chain as “repeating unit”.

The acid value of the dispersant in the present invention is preferably 0 to 30 mgKOH / g, more preferably 0 to 20 mgKOH / g, and particularly preferably 0 to 10 mgKOH / g.
If the acid value is too large, the hydrophilicity becomes strong, and when forming droplets in an aqueous medium, it becomes difficult for the color pigment to be taken into the polymerizable monomer, and the color pigment may come out on the surface of the toner particles. In addition, since the droplets are deformed or aggregated without being stabilized, the shape, particle size, particle size distribution, etc. of the toner particles may not be suitably controlled.

The dispersant in the present invention has the chemical structure as described above, but the production method is not particularly limited, and at least diisocyanate, an organic group having a repeating unit, an active hydrogen-containing group and a tertiary amino acid. What is necessary is just to be obtained by the reaction of a compound having a group.
Further, the dispersant in the present invention may have a chemical structure as described above, but may be modified within the range where the above-described effects are exhibited. That is, the present invention provides a color pigment dispersion for toner particles containing a color pigment, a dispersant, and a polymerizable vinyl group-containing monomer, wherein the dispersant is at least a diisocyanate and an organic group having a repeating unit. And a coloring pigment dispersion for toner particles obtained by reacting a compound having an active hydrogen-containing group and a tertiary amino group.

Particularly preferred specific examples of the dispersant in the present invention are listed below.

In the formula (3), Z represents “an organic group having a repeating unit”, preferably a polyester chain or a polyalkylene glycol chain. Preferred ranges of the “polyester chain” and the “polyalkylene glycol chain” are the same as those described above, and particularly preferable are those represented by the formula (S1), formula (S3), formula (S5) or formula (S6). Is. The left-right orientation of “-Z-” is determined with chemical common sense from among those represented by the formula (S1), the formula (S3), the formula (S5) or the formula (S6) and the left-right flip.

Several Z represented by Formula (3) may mutually be same or different, However, It is preferable that it is the same. The number of repeating units in the plurality of Z may be the same or different from each other, but is preferably the same.
Moreover, several R < ⁴ > in Formula (3) is the same as that of above-described R < ¹ >. Several R < ⁴ > may mutually be same or different, However, It is preferable that it is the same.
Moreover, several R < ³ > in Formula (3) is the same as that of R < ² > in above-described Formula (1) also including a preferable substitution position. Several R < ³ > may mutually be same or different, However, It is preferable that it is the same.
M ′ in the formula (3) is the same as m in the above-described formula (1).

When the isocyanurate ring-containing compound represented by formula (3) is a mixture, the number of isocyanurate rings in the ring-containing compound in formula (3) is more preferably 1 to 4 on average, and 1.2 It is particularly preferred that the number is 2.5.

Among these, in Formula (3), R ³ is more preferably a methyl group, and R ³ is more preferably bonded to the ortho or para position of the isocyanate group substituted on the benzene ring.
That is, the isocyanurate ring-containing compound possessed by the dispersant represented by formula (3) preferably has an isocyanurate ring formed by trimerization of tolylene diisocyanate. It is particularly preferred that the tolylene diisocyanate has an isocyanurate ring formed by trimerization.

Although omitted in Formula (3), it is also preferable that an “amine value-imparting compound” is bonded to an isocyanate group or the like of the ring-containing compound.
Specific examples of the “amine value-imparting compound” include the following.
—NH—CO—NH—C ₂ H ₄ —N (CH ₃ ) ₂
—NH—CO—NH—C ₃ H ₆ —N (CH ₃ ) ₂
—NH—CO—NH—C ₂ H ₄ —C ₅ H ₄ N
(—C ₅ H ₄ N represents a pyridine residue)
—NH—CO—NH—C ₃ H ₆ —C ₃ H ₃ N ₂
(—C ₃ H ₃ N ₂ represents an imidazole residue)

Further preferred specific examples of the dispersant in the present invention are listed below.

In the formula (4), X represents “an organic group having a repeating unit”, and preferably represents a polyester chain or a polyalkylene glycol chain. Preferred ranges of the “polyester chain” and the “polyalkylene glycol chain” are the same as those described above, and particularly preferable are those represented by the formula (S1), formula (S3), formula (S5) or formula (S6). Is. Furthermore, among them, those represented by formula (S5) or (S6) are more preferred, and most preferred are those represented by formula (S6).
The left-right orientation of “—X—” is determined with chemical common sense from among those represented by formula (S1), formula (S3), formula (S5), or formula (S6) and the left-right flip.

Several X represented by Formula (4) may mutually be same or different, However, It is preferable that it is the same.
Moreover, several R < ¹ > in Formula (4) is as above-mentioned. Several R < ¹ > may mutually be same or different, However, It is preferable that it is the same.
The number of repeating units in the plurality of X may be the same or different from each other, but is preferably the same.

The preferred range of the linking group Y is the same as described above, and specific examples include a simple bond (no linking group), an alkylene group, an arylene group, and an alkenylene group.

T is preferably 0, 1 or 2. The dispersant represented by formula (4) may be a mixture or a mixture having different t. In this case, the average value of t is preferably 0.15 to 1, and preferably 0.18 to 0.00. 9 is more preferable, and 0.2 to 0.8 is particularly preferable. Within this range, the pigment adsorbing power and hydrophilicity balance of the dispersant are excellent.

Although omitted in Formula (4), it is also preferable that an “amine value-imparting compound” is bonded to an isocyanate group or the like of the ring-containing compound.
Specific examples of the “amine value-imparting compound” include the following.
—NH—CO—NH—C ₂ H ₄ —N (CH ₃ ) ₂
—NH—CO—NH—C ₃ H ₆ —N (CH ₃ ) ₂
—NH—CO—NH—C ₂ H ₄ —C ₅ H ₄ N
(—C ₅ H ₄ N represents a pyridine residue)
—NH—CO—NH—C ₃ H ₆ —C ₃ H ₃ N ₂
(—C ₃ H ₃ N ₂ represents an imidazole residue)

The preferred dispersant in the present invention has the chemical structure as described above, but the production method is not particularly limited.

<Coloring pigment>
The color pigment dispersion for toner particles of the present invention is a color pigment dispersion for toner particles containing a color pigment, a dispersant, and a polymerizable vinyl group-containing monomer. The color pigment is not particularly limited. And a coloring pigment used for toner particle production. The colored pigment includes black pigments such as carbon black.

Specific examples of the color pigment include carbon black, nigrosine dye, iron black, naphthol yellow S, Hansa yellow (10G, 5G, G), cadmium yellow, yellow iron oxide, ocher, yellow lead, titanium yellow, Polyazo yellow such as disazo yellow, oil yellow, Hansa yellow (GR, A, RN, R), pigment yellow L, benzidine yellow (G, GR), permanent yellow (NCG), Vulcan fast yellow (5G, R), Tartrazine lake, quinoline yellow lake, anthrazan yellow BGL, isoindolinone yellow, bengara, red lead, lead vermilion, cadmium red, cadmium mercurial red, antimon vermilion, permanent red 4R, para red, fise red, parachlor ortho nitro Ani Red, Resol Fast Scarlet G, Brilliant Fast Scarlet, Brilliant Carmine B, Permanent Red (F2R, F4R, FRL, FRLL, F4RH), Fast Scarlet VD, Belkan Fast Rubin B, Brilliant Scarlet G, Resol Rubin GX, Permanent Red F5R, Brilliant Carmine 6B, Pigment Scarlet 3B, Bordeaux 5B, Toulouse Maroon, Permanent Bordeaux F2K, Helio Bordeaux BL, Bordeaux 10B, Bon Maroon Light, Bon Maroon Medium, Eosin Lake, Rhodamine Lake B, Rhodamine Lake Y, Alizarin Lake, Thioindigo Red B, thioindigo maroon, oil red, quinacridone red, pyrazolone red, dys Polyazo red such as zored, chrome vermilion, benzidine orange, perinone orange, oil orange, cobalt blue, cerulean blue, alkali blue rake, peacock blue rake, Victoria blue rake, metal free phthalocyanine blue, phthalocyanine blue, fast sky blue, in Dunslen Blue (RS, BC), Indigo, Ultramarine Blue, Bitumen, Anthraquinone Blue, Fast Violet B, Methyl Violet Lake, Cobalt Purple, Manganese Purple, Dioxane Violet, Anthraquinone Violet, Chrome Green, Zinc Green, Chrome Oxide, Pyridian, Emerald Green, Pigment Green B, Naphthol Green B, Green Gold, Acid Green Lake, Malachite Green Examples include lake, phthalocyanine green, anthraquinone green, titanium oxide, zinc white, and lithobon.
In addition, you may use together well-known dye with the said pigment. These may be used individually by 1 type and may use 2 or more types together.

C.I. I. As a number, specifically, C.I. I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 39, 40, 41, 48, 48: 2, 48: 3, 48: 4, 49, 50, 51, 52, 53, 54, 55, 57, 57: 1, 58, 60, 63, 64, 68, 81, 81: 1, 83, 87, 88, 89, 90, 112, 114, 122, 123, 144, 146, 147, 150, 163, 166, 169, 177, 184, 185 186, 202, 206, 207, 209, 220, 221, 238, 254, 269; I. Pigment violet 19, 32; I. Vat Red 1, 2, 10, 13, 15, 23, 29, 35, C.I. I. Pigment Blue 1, 2, 3, 7, 15, 15: 1, 15: 2, 15: 3, 15: 4, 16, 17, 60, 62, 66; I. Bat Blue 6; C.I. I. Acid Blue 45, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 62, 65, 73, 74, 81, 83, 93, 94, 95, 97, 98, 109, 110, 111, 117, 120, 127, 128, 129, 137, 138, 139, 147, 150, 151, 154, 155, 167, 168, 173, 174, 175, 176 180, 181, 183, 185, 191, 194, 213; C.I. I. Vat yellow 1, 3, 20 etc. are mentioned.
In addition, you may use together well-known dye with the said pigment. These may be used individually by 1 type and may use 2 or more types together.

<Polymerizable monomer>
The color pigment dispersion for toner particles of the present invention is a color pigment dispersion for toner particles containing a color pigment, a dispersant, and a polymerizable vinyl group-containing monomer. The “containing monomer” (polymerizable monomer) is not particularly limited, and those used for toner particle production are used.

Specific examples of the polymerizable monomer include styrenes such as styrene, p-chlorostyrene, and α-methylstyrene; methyl (meth) acrylate, ethyl (meth) acrylate, and n- (meth) acrylate. Propyl, iso-propyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, (meth) acrylic acid-n-octyl, (meth ) (Meth) acrylate compounds such as 2-ethylhexyl acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, phenyl (meth) acrylate; vinyl esters such as vinyl acetate and vinyl propionate; acrylonitrile, methacrylate Vinyl group-containing nitriles such as rhonitrile; vinyl such as (meth) acrylamide -Containing amides; vinyl group-containing ethers such as vinyl methyl ether and vinyl isobutyl ether; vinyl group-containing ketones such as vinyl methyl ketone, vinyl ethyl ketone and vinyl isopropenyl ketone; olefins such as ethylene, propylene and butadiene; And unsaturated polyenes such as isoprene;

As the polymerizable monomer, styrene and / or (meth) acrylate compounds are used from the viewpoint of glass transition point (Tg), softening point, copolymerizability, viscosity, etc., and because they are frequently used in the production of toner particles. It is more preferable that Furthermore, n-butyl acrylate is particularly preferred as the (meth) acrylate compound.

The polymerizable monomer may be one kind or a mixture of two or more kinds, but in the case of one kind, it is itself, and in the case of two or more kinds, the mixed state is liquid at normal temperature (20 ° C.). It is preferable that it is easy to disperse.

The polymerizable monomer contained in the color pigment dispersion for toner particles of the present invention is not limited to the polymerizable monomer used as a dispersion medium when the color pigment is dispersed together with the dispersant. The polymerizable monomer includes a polymerizable monomer blended in the production of toner particles. That is, the color pigment dispersion for toner particles of the present invention may be polymerized without adding a polymerizable monomer thereto, or may be polymerized by further blending with another or the same type of polymerizable monomer. It may be.

The ratio of the color pigment, the dispersant and the polymerizable monomer in the color pigment dispersion for the toner particles of the present invention is not particularly limited as long as a good dispersion state of the color pigment can be obtained and the dispersion state can be maintained. The dispersant is preferably 5 to 80 parts by weight, more preferably 10 to 60 parts by weight, and particularly preferably 20 to 50 parts by weight with respect to 100 parts by weight of the pigment. Within this range, the effects of the present invention described above can be easily achieved.
Further, 2 to 30 parts by weight of the color pigment is preferable, more preferably 2.5 to 20 parts by weight, and particularly preferably 3 to 15 parts by weight with respect to 100 parts by weight of the polymerizable monomer. Within this range, the effects of the present invention described above can be easily achieved. Since the color pigment dispersion for toner particles of the present invention may be a “color pigment master batch”, it may have a concentration higher than the concentration of the color pigment in the toner particles.

<Dispersing method of coloring pigment>
In the present invention, the method for dispersing the colored pigment in the vinyl group-containing monomer having a polymerizable double bond is not particularly limited, but a bead mill using zirconia beads, alumina beads, stainless beads, quartz beads, glass beads, etc. ; Paint shaker using beads of the same material; Ball mill using beads of the same material; Homo mixer, homogenizer, colloid mill, dissolver, attritor, sand mill, high speed mill, two rolls, three rolls, high pressure Examples of the dispersion method include a disperser and an ultrasonic disperser. It should be noted that there may be overlap in the above distribution methods.
It is easy to obtain toner particles that can be finely dispersed and have good dispersibility and dispersion stability. In particular, toner particles having an average pigment abundance ratio of 0.6 or more can be easily obtained, and a color pigment having a sharp particle size distribution can be obtained. Therefore, a bead mill is particularly preferable.

The beads used in the bead mill are not particularly limited, but zirconia beads or alumina beads are preferred because of their large specific gravity and good durability. The diameter of the beads is preferably from 0.01 mm to 5 mm, more preferably from 0.03 mm to 3 mm, and particularly preferably from 0.1 mm to 2 mm from the viewpoint that fine dispersion is possible.

It is also preferable to disperse in two or more stages by changing the dispersion conditions because toner particles having an average pigment abundance ratio of 0.6 or more can be easily obtained. When dispersing in two or more stages, the first half is dispersed using beads having a diameter of 0.3 to 5 mm (particularly preferably 1 to 3 mm), and the latter half is using beads having a smaller diameter. And dispersing. Specifically, the latter half is preferably dispersed using beads having a diameter of 0.03 to 0.7 mm.

<Toner for electrostatic image development>
The present invention relates to a toner for developing an electrostatic charge image obtained by using the color pigment dispersion for toner particles, wherein the color pigment is dispersed in a vinyl group-containing monomer having a polymerizable double bond in the presence of a dispersant. The volume average particle diameter (Dv) of the suspension polymerized toner particles obtained in the inorganic colloid aqueous solution is 2 μm or more and 10 μm or less in the colored pigment dispersion and the toner raw material liquid containing at least the thermal polymerization initiator. An electrostatic charge image developing toner containing suspension polymerized toner particles that are suspended and dispersed to form a thermal polymerization, and the presence of pigment in the cross section of one particle of the electrostatic charge image developing toner The toner for developing an electrostatic charge image is preferably characterized in that the average pigment abundance ratio obtained by averaging the ratios is 0.6 or more.

The number average particle diameter of the colored pigment after dispersion is preferably 5 nm to 100 nm, and particularly preferably 10 nm to 80 nm. By using the above-described color pigment dispersion method, it is easy to obtain a color pigment having a number average particle diameter in the above range, and the state in which the color pigment is uniformly incorporated into the polymerizable monomer in the toner particle forming process is maintained. It is difficult to obtain toner particles in which a large amount of colored pigment is present in the vicinity of the surface of the toner particles. As a result, the pigment abundance ratio tends to be 0.6 or more, the environmental characteristics are good, and the chargeability can be controlled. It becomes easy to do.

<Thermal polymerization initiator>
The “toner raw material liquid” preferably contains a thermal polymerization initiator.
The thermal polymerization initiator is not particularly limited and known ones can be used. A thermal polymerization initiator may be used individually by 1 type, and may use 2 or more types together.

<Combination agent>
In the toner raw material liquid in the present invention, in addition to the color pigment dispersion liquid and the thermal polymerization initiator which are essential components, an additional polymerizable monomer and monomer other than the polymerizable monomer used as a dispersion medium in the color pigment dispersion liquid Wax, polymer wax, lubricant, dispersion aid, dispersibility improving polymer, polymerizable polymer, polymerizable oligomer, polyfunctional polymerizable monomer, thermal polymerization inhibitor, chain transfer agent, dye, inorganic fine particles (internally added particles), polymerization A compounding agent such as an organic solvent having no property, a positive charge control agent, a negative charge control agent, and magnetic powder can be appropriately contained.

The kind of the “additional polymerizable monomer other than the polymerizable monomer used as the dispersion medium for the color pigment dispersion” may be the same as the polymerizable monomer used as the dispersion medium for the color pigment dispersion. . That is, the same type of dispersion medium may be added.
In addition, the “organic solvent having no polymerizability” includes a reaction solvent that has not been removed by use when the dispersant is synthesized.

<Method for producing toner particles>
The above-mentioned color pigment dispersion for toner particles is preferably suspended or emulsified in an aqueous medium and polymerized to produce toner particles. That is, the color pigment dispersion for toner particles of the present invention can be suitably used in the above (b-1) suspension polymerization method.
However, it can also be used in polymerization methods other than suspension polymerization methods such as (b-2) emulsion aggregation methods, and can also be used in (c) dissolution granulation methods and the like.

When used in the suspension polymerization method, if necessary, the above-described “compound other than the color pigment, the dispersant and the polymerizable monomer” is added to the color pigment dispersion for toner particles of the present invention, and a predetermined amount is added to the aqueous phase. Suspend to a particle size and polymerize by heating or the like.

The main component of the aqueous phase is water, but a dispersion stabilizer may be added if necessary. The dispersion stabilizer stabilizes the droplets by forming a hydrophilic colloid. Examples of the dispersion stabilizer include calcium carbonate, magnesium carbonate, barium carbonate, tricalcium phosphate, hydroxyapatite, silicate diatomaceous earth, and clay.

When the color pigment dispersion for toner particles of the present invention is used in (b-2) the emulsion aggregation method, the color pigment dispersion for toner particles of the present invention and an emulsion dispersion of a binder resin of toner particles in an aqueous medium. And, if necessary, the toner particles are obtained by mixing and co-aggregating the above dispersion of the compounding material.
When the color pigment dispersion for toner particles of the present invention is used in (c) the dissolution granulation method or the like, toner particles can be obtained by using it as a master batch of color pigments.

It is particularly preferable that the toner raw material liquid is suspended in an aqueous medium and polymerized to produce toner particles. That is, the toner raw material liquid can be suitably used in the above-described (b-1) suspension polymerization method.

<Inorganic colloidal aqueous solution>
In the present invention, a suspension polymerization method is used, and the toner raw material liquid is suspended and dispersed in an inorganic colloidal aqueous solution so that the volume average particle diameter (Dv) of the obtained suspension polymerization toner particles is 2 μm or more and 10 μm or less. It is preferable to make it.
The “inorganic colloid” functions as a dispersion stabilizer that stably suspends and disperses the toner raw material liquid in the aqueous medium.
Compared to organic colloids, dissolved organic dispersion stabilizers, etc., inorganic colloids stabilize suspension droplets and stabilize the shape and particle size distribution during polymerization in aqueous media. In addition, the colored pigment is uniformly dispersed in the suspension droplets and toner particles, which contributes to the suppression of the aggregation of the suspension droplets and toner particles on the surface.

The inorganic colloid as a dispersion stabilizer that stably suspends and disperses the toner raw material liquid in the aqueous medium is surprisingly well-balanced by the above-described color pigment dispersant as compared with the organic dispersion stabilizer. Improves the dispersibility of the colored pigment imparted with hydrophilicity in the polymerizable monomer.
Dispersibility is improved by the synergistic effect of the dispersant for dispersing the color pigment in the polymerizable monomer, the type of the color pigment, and the dispersion method for dispersing the color pigment in the polymerizable monomer, and in particular, the average pigment abundance ratio Thus, a novel suspension polymerized toner particle having a N value of 0.6 or more and a novel toner for developing an electrostatic image can be obtained.

Examples of the “inorganic colloid” include, but are not limited to, calcium carbonate, magnesium carbonate, barium carbonate, tricalcium phosphate, magnesium hydroxide, hydroxyapatite, diatomaceous earth silicate, clay, and the like. Is mentioned.
Particularly preferred is tricalcium phosphate or magnesium hydroxide from the above points.

The particle diameter of the colloidal particles is not particularly limited, but is preferably 0.02 μm to 1 μm, particularly preferably 0.1 μm to 0.5 μm.
The “inorganic colloidal aqueous solution” refers to those in which the inorganic colloidal particles are not literally dissolved in water but exist as colloidal particles.
In the toner raw material liquid, the above-described inorganic colloid and, if necessary, a polymer dispersion stabilizer may be used in combination.

<Toner particles, toner for developing electrostatic images>
Toner particles are obtained by filtering and drying after polymerization. The toner particles are externally added with flame retardant silica, alumina, titania and other external additives to obtain the toner (toner) for developing an electrostatic image of the present invention. When toner is obtained by externally adding toner particles, the toner particles and the external additive are agitated and mixed with a high-speed agitator or the like.

<Pigment abundance, average pigment abundance>
The “pigment abundance ratio” in the present invention is a scale representing the uniformity of the distribution of the colored pigment in the toner particles or in the toner, and is calculated as follows.

A TEM image obtained by observing and photographing an arbitrary toner particle or a toner after external addition using a transmission electron microscope (TEM), a cross-section obtained by thinly cutting the toner particle on a plane passing through the vicinity of the center of the toner particle. By trimming the background portion of the toner particles, a rectangle whose four sides are inscribed in the toner particles is obtained.
The long side of the rectangle is divided into 20 equal parts, and parallel straight lines are drawn parallel to the long and short sides of the rectangle so as to be orthogonal to each other to create a square. This square can be 20 × 20 when the TEM image of the toner particles is a perfect circle, but when the short side is shorter than the long side, 20 × (20−n) [n is 1 or more and 19 or less. Integer].
Hereinafter, each of the squares is referred to as a “mesh”.

Among the above-mentioned cells, a cell containing even a small amount of toner particles is referred to as “a cell including toner particles”, and a cell including any pigment is referred to as “a cell including pigment”.
A value obtained by dividing the number of “cells containing toner particles” by the number of “cells containing pigment” is defined as “pigment abundance ratio” in the present invention.

For example, the cross-sectional view of the toner particles in FIG. 3 is a TEM image of “suspension polymerization toner particles FKT3” produced in Experimental Example F04 at a magnification of 2100.
In FIG. 3, a grid having a portion darker than the background portion (toner particle portion) is “a grid containing toner particles”, and a grid having a dark portion (pigment) is “ It is a "mesh that contains a pigment". In the figure, it is clear that “the cell containing the pigment” has a relatively dark background compared to “the cell containing no pigment”, and which cell is counted as “the cell containing the pigment”. It is.

The “average pigment abundance ratio” means that any four toner particles or toner for developing an electrostatic image is selected, the pigment abundance ratio in a cross section of one toner particle is measured and calculated, and these four additions are added. Say the average value.

If toner particles are produced using a specific color pigment and a specific production method using the color pigment dispersion for toner particles of the present invention, the average pigment abundance ratio of the toner can be 0.6 or more. If such a toner is used, the color pigment is uniformly dispersed inside the toner particles, and the color density of the obtained toner is improved.
In the toner of the present invention, the average pigment abundance ratio obtained by averaging the pigment abundance ratios in the cross section of one particle is preferably 0.6 or more. By satisfying such conditions, a toner for developing an electrostatic image capable of obtaining a sufficient color density can be obtained, and the above-described excellent effects can be obtained.

<Circularity, average circularity>
The values measured by the method described in the examples are defined as “circularity” and “average circularity” in the present invention.
In the present invention, the average circularity of the suspension-polymerized toner particles (that is, the average circularity of the electrostatic image developing toner) is preferably 0.95 or more, particularly preferably 0.96 or more. If the degree of circularity is low, the charge amount is not stable, which causes unevenness and background stains during printing.

<Toner production method>
The present invention is a method for producing a toner using the above-described color pigment dispersion for toner particles, wherein the color pigment is used in the presence of a dispersant as beads having a diameter of 0.01 mm or more and 5 mm or less. A colored pigment dispersion is prepared by dispersing in a vinyl group-containing monomer having a polymerizable double bond, and at least a thermal polymerization initiator is blended in the colored pigment dispersion to prepare a toner raw material liquid. The suspension is dispersed in an inorganic colloidal aqueous solution so that the volume average particle diameter (Dv) of the resulting suspension polymerization toner particles is 2 μm or more and 10 μm or less, and then thermally polymerized to obtain suspension polymerization toner particles. It is also a method for producing a toner for developing an electrostatic image having an average pigment abundance ratio of 0.6 or more, which comprises a production step.

<Type and use of toner>
The electrostatic image developing toner of the present invention is used for the production of full color toners such as cyan toner, magenta toner, yellow toner and black toner; and other color toners.
The electrostatic image developing toner of the present invention can be used as a one-component toner such as a magnetic one-component toner or a non-magnetic one-component toner, or can be mixed with a magnetic carrier and used as a two-component developer. .
As the magnetic substance internally added to the magnetic one-component toner, a known magnetic substance such as magnetite is used.

As the magnetic carrier of the two-component developer, known ones such as iron powder, magnetite powder, ferrite powder, magnetic resin powder having an average diameter of about 50 to about 150 μm can be used. Also, a magnetic carrier whose surface is coated with a resin such as a silicone resin, an acrylic resin, or a fluorine resin can be used. The mixing ratio of the magnetic carrier and the toner is preferably 10 to 100 parts by weight with respect to 1 part by weight of the toner.

<Action and principle>
The dispersant in the present invention provides excellent dispersibility of the color pigment in the polymerizable monomer, and the suspension of the polymerizable monomer in the aqueous medium and the polymerization pigment are excellent in the polymerizable monomer. Although the action and principle that can maintain the dispersibility and the uptake and can suitably control the shape, particle size, particle size distribution, etc. of the toner particles are not clear, the following may be considered. However, the present invention is not limited to the range of the following effects.
That is, if the dispersing agent is too hydrophilic, the coloring pigment can be dispersed in the polymerizable monomer, but such a dispersing agent has a stronger affinity for water than the adsorptivity to the coloring pigment. It is considered that the suspension stability is lost in the aqueous medium of the polymerizable monomer containing the dispersant.

On the other hand, when the dispersant has a strong hydrophobicity and a weak polarity, it is difficult for the dispersant to be adsorbed to the colored pigment in the first place, so that the colored pigment is difficult to disperse in the polymerizable monomer, resulting in a poorly colored toner.
The dispersant in the present invention is excellent in the hydrophobic / hydrophilic balance, excellent in dispersion stabilization in the polymerizable monomer, and in suspension stability in the aqueous medium. It is considered that a toner having a uniform shape could be obtained.

The type and amount of the dispersant provide excellent dispersibility of the color pigment in the polymerizable monomer, and it is combined with the inorganic colloidal aqueous solution during the suspension and polymerization of the polymerizable monomer in the aqueous medium. Although the good dispersibility and incorporation of the colored pigment into the polymerizable monomer (inside the droplet) is maintained, the action and principle that can suitably control the shape, particle size, particle size distribution, etc. of the toner particles are not clear. The following can be considered. However, the present invention is not limited to the range of the following effects.

That is, if the dispersing agent is too hydrophilic, the coloring pigment can be dispersed in the polymerizable monomer, but such a dispersing agent has a stronger affinity for water than the adsorptivity to the coloring pigment. It is considered that the suspension stability is lost in the aqueous medium of the polymerizable monomer containing the dispersant. Further, it is considered that the uniform dispersion inside the toner particles is hindered and the average pigment abundance ratio is lowered, in particular, less than 0.6.

On the other hand, if the dispersant is too hydrophobic and too polar, it is difficult for the dispersant to be adsorbed to the colored pigment in the first place, so that the colored pigment is difficult to disperse in the polymerizable monomer, resulting in a toner with poor color development. In addition, if the coloring pigment itself is too hydrophilic, the dispersant is easily adsorbed, but the suspension stability is likely to collapse, and if the coloring pigment itself is too hydrophobic, the dispersant is difficult to adsorb, The dispersibility is poor, the average pigment abundance ratio is low, and the toner has poor color development.

The dispersant is excellent in hydrophobic / hydrophilic balance and contributes to the dispersion stabilization in the polymerizable monomer and the suspension stabilization in the aqueous medium. By the combination of a suitable dispersant and a suitable color pigment, It is considered that a toner having an average pigment abundance ratio of 0.6 or more, excellent dispersibility, and a uniform particle shape and particle diameter could be obtained.

On the other hand, if the properties of the colored pigment itself or the surface treatment of the colored pigment are poor, the average pigment abundance ratio may not increase, and in particular, it may not exceed 0.6. Even if the dispersant is excellent in pigment dispersibility, the average pigment abundance ratio may not be increased if the properties of the color pigment itself and the combination suitability (matching property) with the surface treatment of the color pigment are poor.
In order to increase the average pigment abundance ratio, a pigment whose acid treatment is not too strong is preferable because it is less likely to be attracted to the aqueous medium side, the shape during polymerization is less likely to collapse, and the particle size distribution is easily stabilized. Conceivable.

Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples as long as the gist thereof is not exceeded.

Production Example 1
<Synthesis of polyester chain a>
7.2 parts by mass of n-octanol, 92.8 parts by mass of ε-caprolactone and 0.003 parts by mass of dibutyltin dilaurate were homogenized under a protective atmosphere and heated to 160 ° C. within 1 hour. The addition reaction was immediately terminated when a solids content of 99% by weight was obtained. At this temperature, the solids content was achieved in 10-12 hours. The product was obtained as a colorless solid at room temperature. The solid is abbreviated as “polyester chain a”.

The number average molecular weight of the polyester chain a was 1800, and the melting point was 50 to 60 ° C.

Production Example 2
<Synthesis of polyester chain b>
9 parts by mass of 1,4-butanediol, 91 parts by mass of ε-caprolactone and 0.002 parts by mass of dibutyltin dilaurate were homogenized under a protective atmosphere and heated to 160 ° C. within 1 hour. The addition reaction was completed immediately when the solid content reached 99% by mass or more.

The number average molecular weight of the polyester chain b which is the produced polyester diol was 1000.

Production Example 3
<Synthesis of Dispersant A>
In 16.1 parts by mass of a solution obtained by dissolving “a ring-containing compound having four isocyanate groups in one molecule represented by the formula (1)” in 51% by mass in butyl acetate, and 20 parts by mass of xylene 11 parts by mass of the dissolved “polyester chain a obtained in Production Example 1” is added to 20 parts by mass of ethyl cellosolve / xylene (volume ratio 1/1) in a protective atmosphere, and 0.002 parts by mass of dibutyltin dilaurate as a catalyst. Then, addition reaction was performed at room temperature.

When 20 mol% of the isocyanate groups had reacted, 3.8 parts by mass of “polyester chain b obtained in Production Example 2” dissolved in 17.1 parts by mass of xylene was added.
Further, after 55 mol% of the isocyanate groups had reacted, 10 parts by mass of xylene and “2.0 parts by mass of 4- (2-aminoethyl) pyridine dissolved in 10 parts by mass of diisobutyl ketone” were added.
The reaction mixture was stirred for 1 hour while heating to 50 ° C.

A colorless, slightly yellow, low viscosity product was obtained. The dispersant contained in this product is abbreviated as “dispersant A”. In the formula (4), the dispersant A is one in which X is represented by the formula (S3), t is 0.7, and R ¹ is an alkyl group having 10 carbon atoms.
Similar to a structure with —NH—CO—NH—C ₂ H ₄ —C ₅ H ₄ N (where —C ₅ H ₄ N represents a pyridine residue).

Production Example 4
<Synthesis of Dispersant B>
In Production Example 3, Production Example 3 except that polypropylene glycol having a number average molecular weight of 810 was used instead of “polyester chain a obtained in Production Example 1” and “polyester chain b obtained in Production Example 2”. In the same manner, a colorless, slightly yellow and low-viscosity product was obtained.
The dispersant contained in this product is abbreviated as “dispersant B”. In the formula (4), the dispersant B is one in which X is represented by the formula (S6), t is 0.4, and R ¹ is an alkyl group having 4 carbon atoms.
Similar to a structure with —NH—CO—NH—C ₂ H ₄ —C ₅ H ₄ N (where —C ₅ H ₄ N represents a pyridine residue).

Production Example 5
<Synthesis of Dispersant C>
In Production Example 4, a colorless, slightly yellow and low-viscosity product was obtained in the same manner as in Production Example 4 except that polypropylene glycol having a number average molecular weight of 860 was used instead of polypropylene glycol having a number average molecular weight of 810. .
The dispersant contained in this product is abbreviated as “dispersant C”.
Dispersant C is the one in formula (4), wherein X is represented by formula (S6), t is 0.4, and R ¹ is an alkyl group having 4 carbon atoms.

Experimental example A1
<Preparation of Colored Pigment Dispersion Liquid Y1 for Toner Particles>
The liquid having the following composition was dispersed for 5 hours using a zirconia bead (φ = 0.5 mm) with a paint shaker to obtain “colored pigment dispersion Y1 for toner particles”.
Pigment “CI Pigment Yellow 155 (CI PY155)”: 5 parts by weight Dispersant A: 2 parts by weight as solid content Styrene: 80 parts by weight Butyl acrylate: 20 parts by weight

Experimental example A2
<Preparation of Colored Pigment Dispersion Liquid Y2 for Toner Particles>
A “color pigment dispersion Y2 for toner particles” was obtained in the same manner as in Experimental Example A1, except that Dispersant B was used instead of Dispersant A in Experimental Example A1.

Experimental Example A3
<Preparation of Colored Pigment Dispersion C1 for Toner Particles>
In Experimental Example A2, the pigment “CI Pigment Blue 15: 3 (CI PB15: 3)” was used instead of the pigment “CI Pigment Yellow 155 (CI PY155)” In the same manner as in Experimental Example A2, “Colored Pigment Dispersion Liquid 3 for Toner Particles” was obtained.

Experimental Example A4
<Preparation of Colored Pigment Dispersion Liquid K1 for Toner Particles>
Experimental example A2 except that the pigment “carbon black, NIPex 150: manufactured by Orion Engineered Carbons Co., Ltd.” was used instead of the pigment “CI Pigment Yellow 155 (CI PY155)”. In the same manner as A2, “color pigment dispersion liquid K1 for toner particles” was obtained.

Experimental Example A5
<Preparation of Colored Pigment Dispersion y1 for Toner Particles>
In Example A1, “Dispersion pigment for toner particles” was used in the same manner as in Example A1, except that the dispersant “Azisper PB821”, which is a polyallylamine derivative manufactured by Ajinomoto Fine Techno Co., Ltd., was used instead of the dispersant A. Dispersion liquid y1 ”was obtained.

Experimental Example A6
<Preparation of Colored Pigment Dispersion Liquid y2 for Toner Particles>
In Experimental Example A1, a dispersing agent “BYK-LPN6919” which is a linear acrylic block copolymer manufactured by Big Chemie Japan Co., Ltd. was used in place of the dispersing agent A, and the same procedure as in Experimental Example A1 was performed. A “color pigment dispersion y2 for toner particles” was obtained.

Experimental Example A7
<Preparation of Colored Pigment Dispersion y3 for Toner Particles>
As in Experimental Example A1, “Toner” was used in the same manner as in Experimental Example A1, except that the dispersing agent “DISPERBYK2001”, which is a linear acrylic block copolymer manufactured by Big Chemie Japan Co., Ltd., was used instead of dispersing agent A. A colored pigment dispersion y3 for particles ”was obtained.

Experimental Example A8
<Preparation of colored pigment dispersion c1 for toner particles>
In Experimental Example A5, the pigment “CI Pigment Blue 15: 3 (CI PB15: 3)” was used in place of the pigment “CI Pigment Yellow 155 (CI PY155)”. In the same manner as in Experimental Example A5, a “color pigment dispersion liquid c1 for toner particles” was obtained.

Experimental Example A9
<Preparation of Colored Pigment Dispersion Liquid k1 for Toner Particles>
Experimental Example A5 except that the pigment “Carbon Black, NIPex150: manufactured by Orion Engineered Carbons Co., Ltd.” was used instead of the pigment “CI Pigment Yellow 155 (CI PY155)”. In the same manner as A5, “color pigment dispersion liquid k1 for toner particles” was obtained.

Experimental Example A10
<Preparation of Colored Pigment Dispersion Liquid k2 for Toner Particles>
In Experimental Example A5, except that Pigment “Carbon Black, # 25: manufactured by Mitsubishi Chemical Corporation” was used instead of Pigment “CI Pigment Yellow 155 (CI PY155)”, Experimental Example A5 and Similarly, “color pigment dispersion liquid k2 for toner particles” was obtained.

Evaluation Example 1
<Manufacture of toner particles>
Magnesium chloride and ion-exchanged water were put into a 500 mL flask, and after dissolution, an aqueous sodium hydroxide solution was added dropwise to prepare an inorganic colloid aqueous solution.
A liquid in which a polymerization initiator t-butyl-peroxy-2-ethylhexanoate (manufactured by Nippon Oil & Fats Co., Ltd., “Perbutyl O”) was added to the color pigment dispersion for toner particles was added. After stirring at 12000 rpm for 10 minutes with a mixer, polymerization was carried out by heating at 80 ° C. for 4 hours while stirring in a nitrogen atmosphere.
After acid treatment with sulfuric acid so that the pH was 4 or less, the particles were washed with ion-exchanged water and dried to obtain toner particles.

Evaluation example 2
<(1) Measuring Method of “Viscosity” of Colored Pigment Dispersion Liquid for Toner Particles>
Using a tuning fork type vibration viscometer (device name: SV-10 (manufactured by A & D)), the viscosity was measured at 25 ° C. and judged according to the following criteria.
[Criteria]
○: Viscosity is 10 mPa · s or less Δ: Viscosity is larger than 10 mPa · s and smaller than 100 mPa · s ×: Viscosity is 100 mPa · s or more

<(2) Evaluation Method of “Colored Pigment Dispersibility” in Toner Particles>
Observation was performed using a transmission electron microscope (TEM) (device name: Tecnai 12 spirit (manufactured by FEI)), and the following criteria were used.
[Criteria]
◎: Dispersibility is particularly good ○: Dispersibility is good ×: Dispersibility is poor

<(3) Evaluation Method of “Toner Particle Shape”>
Using a scanning electron microscope (SEM) (device name: S-4800 (manufactured by Hitachi, Ltd.)), observation was performed at 1000 times and 10,000 times, and the determination was made according to the following criteria.
However, only Experimental Example A5 was observed at 400 times and 3000 times.
[Criteria]
○: The shape is round and good. ×: The shape is distorted and is defective or defective.

<(4) Method for Measuring “Volume Average Particle Size (Dv) of Toner Particles”>
Using the following apparatus, the volume average particle diameter (Dv) was measured with the following settings, and judged according to the following criteria.
Flow type particle image analyzer: FPIA-3000S (manufactured by Sysmex)
Aperture system: 100 μm
Number of measured particles: 30000 [judgment criteria]
○: Dv = 5 to 10 μm
Δ: Dv = 10 to 20 μm
×: Dv = 20 μm or more

<(5) Measuring method of “Dv / Dp of toner particles”>
Using the above apparatus, the volume average particle diameter (Dv) and the number average particle diameter (Dp) were measured with the above settings, and Dv / Dp was determined and determined according to the following criteria.
[Criteria]
○: Dv / Dp is 1.5 or less Δ: Dv / Dp is 1.5 to 1.6
X: Dv / Dp is 1.6 or more

<(6) Method for Measuring “Average Circularity” of Toner Particles>
Using the above apparatus, the average circularity of the toner particles was measured with the above settings, and judged according to the following criteria [Criteria]
○: Average circularity is 0.98 or more Δ: Average circularity is larger than 0.96 and smaller than 0.98 ×: Average circularity is 0.96 or less

<(7) Measuring method of “reflection density”>
Toner particles (2.0 g) were added to toluene (14 g) and uniformly dissolved and dispersed at room temperature (20 ° C.).
The obtained liquid is coated on coated paper (OK top coat + (150 mm × 100 mm, manufactured by Oji Paper) using a bar coater, and the coating amount after drying is in the range of 0.1 to 0.6 mg / cm ^2. (Coating film area: 100 cm ² ).
It was dried at room temperature (20 ° C.) for 24 hours, and the coated amount (mg / cm ² ) after drying was calculated based on the weight change of the coated paper.
For the measurement of “reflection density”, a Macbeth reflection densitometer was used, and the measurement mode: Reflection, filter “NO” was used to measure five “solid portions”, and the arithmetic mean was calculated.
In addition, it has been confirmed that this measurement method matches the result of the print test with the printer.

<(8) Determination and evaluation method of "0.3mg / cm ² reflection density">
The above measured “reflection density when the coating amount after drying is in the range of 0.1 to 0.6 mg / cm ² ” is plotted with the horizontal axis “coating amount” and the vertical axis “reflection density”. “0.3 mg / cm ² reflection density” was obtained by interpolating to 3 mg / cm ² and judged according to the following criteria.
[Criteria]
○: “0.3 mg / cm ² reflection density” is 1.40 or more Δ: “0.3 mg / cm ² reflection density” is larger than 1.35 and smaller than 1.40 ×: “0.3 mg / cm ² reflection” Concentration "is 1.35 or less

<(9) Measuring method of “acid value” and “amine value”>
The acid value was measured according to JIS K2501.
The amine value was measured according to JIS K7237.

Evaluation results The dispersants are summarized in Table 1.

The evaluation results are summarized in Table 2. In Table 2, “ND” indicates that the numerical value was not measurable.

Further, the color pigment dispersibility (TEM observation) and the shape of toner particles (SEM observation) are shown in FIGS. FIG. 1 shows the case of a yellow coloring pigment (yellow toner), and FIG. 2 shows the case of a cyan or black coloring pigment (cyan toner or black toner).
In FIG. 2, “a lump ND” was a lump, did not have the shape of toner particles, and was not worth putting on a photograph.

As is apparent from the results in Table 2 above, the toner particles produced using the color pigment dispersion for toner particles of the present invention have good results for all the measured items (Experimental Examples A1 to A4). In particular, the dispersant (Experimental Example A2) having a polypropylene glycol chain was good.
The toner particles produced using a dispersant different from the dispersant in the present invention did not give a good overall result (Experimental Examples A5 to A10).

Production Example 6
<Preparation of colored pigment dispersion FK1>
A liquid having the following composition was dispersed at room temperature for 1 hour using a zirconia bead (φ = 2 mm) on a paint shaker, and then dispersed for 3 hours using a zirconia bead (φ = 0.1 mm). Pigment dispersion liquid FK1 "was obtained.

Coloring pigment: Carbon black (manufactured by Orion Engineered Carbons Co., Ltd., NIPex 150) 5 parts by weight Dispersant: Dispersant A 2 parts by weight as a solid content Vinyl group-containing monomer: 80 parts by weight of styrene and 20 parts by weight of butyl acrylate Part

Production Example 7
<Preparation of colored pigment dispersion other than colored pigment dispersion FK1>
Colored pigment dispersions FK2-1 to Fk17 shown in Table 3 were obtained in the same manner as in Production Example 6 except that the color pigment and the dispersant were changed to those shown in Table 3 in Production Example 6.
The numerical values in Table 3 are “parts by mass” as in Production Example 6.

In Table 3, all of the color pigments shown below are carbon black and are described by trade names. The manufacturing or sales companies are as follows.
NIPex150: Orion Engineered Carbons Co., Ltd.
Nerox 3500: Orion Engineered Carbons Co., Ltd.
Nerox 5600: Orion Engineered Carbons Co., Ltd.
# 25: Mitsubishi Chemical Corporation

In Table 3, C.I. I. PB15: 3 is a cyan coloring pigment. I. PY155 is a yellow coloring pigment.

In Table 3, the dispersants are summarized in Table 1 but are as follows.
Dispersant A: Obtained in Production Example 3 Dispersant B: Obtained in Production Example 4 Dispersant C: Obtained in Production Example 5 PB821: Trade name “Azisper PB821”, Ajinomoto Fine Polyallylamine derivative manufactured by Techno Co., Ltd., amine value is 8 mg / KOH / g, acid value is 17 mg / KOH / g
BYK-LPN6919: a linear acrylic block copolymer manufactured by Big Chemie Japan, Inc., amine value is 120 mg / KOH / g, acid value is 0 mg / KOH / g
DISPERBYK 2001: Linear acrylic block copolymer manufactured by Big Chemie Japan Co., Ltd., amine value is 29 mg / KOH / g, acid value is 19 mg / KOH / g

Experimental Example <Production of Suspension Polymerized Toner Particles FKT1>
Into a 500 mL flask, 8.0 g of magnesium chloride and 205.0 g of ion-exchanged water were added, and after dissolution, 46.6 g of a 12.1% by mass aqueous sodium hydroxide solution was added dropwise to prepare an inorganic colloidal aqueous solution.
Here, 94.9 g of the “color pigment dispersion FK1” obtained in Production Example 6 was added to a thermal polymerization initiator t-butyl-peroxy-2-ethylhexanoate (manufactured by NOF Corporation, “Perbutyl O ”) A toner raw material solution containing 5.0 g was added, stirred at 12000 rpm for 10 minutes with a homomixer, dispersed so that the volume average particle diameter (Dv) was 6.92 μm, and then in a nitrogen atmosphere. While stirring, polymerization was carried out by heating at 80 ° C. for 4 hours.
After acid treatment with sulfuric acid so that the pH was 4 or less, washing with ion-exchanged water and drying were performed to obtain “Suspension Polymerized Toner Particles FKT1”.

<Production of Suspension Polymerized Toner Particles Other than Suspension Polymerized Toner Particles FKT1>
Suspension polymerization toner particles other than the suspension polymerization toner particles FKT1 were obtained in the same manner as in the above <Production of suspension polymerization toner particles FKT1>, except that the color pigment dispersion was changed to that shown in Table 3. .
“Volume average particle diameter (Dv)” shown in Table 4 is that of suspension-polymerized toner particles after drying, and the volume average particle diameter (Dv) of suspension-dispersed suspension droplets is almost the same as that. The same.
Therefore, after the toner raw material liquid is added, the mixture is stirred with a homomixer at 12,000 rpm for 10 minutes so that the volume average particle diameter (Dv) becomes “volume average particle diameter (Dv)” shown in Table 4. Distributed.

<Calculation of “average pigment abundance ratio”>
The suspension-polymerized toner particles are cut into a thin piece so as to pass through the center of the suspension-polymerized toner particles, and observed using a transmission electron microscope (TEM) (device name: Tecnai 12 spirit (manufactured by FEI)). The pigment abundance ratio was calculated for each of the four toner particles by the above method. The pigment abundance ratio of the four toner particles was averaged to obtain an “average pigment abundance ratio”.
The value of the “average pigment abundance ratio” is the same even when an external additive is externally added to the suspension polymerization toner particles to obtain an electrostatic image developing toner.

<Method for Measuring “Volume Average Particle Size (Dv) of Toner Particles”>
Using the following apparatus, the volume average particle size (Dv) of the suspension-polymerized toner particles after drying was measured with the following settings.
Flow type particle image analyzer: FPIA-3000S (manufactured by Sysmex)
Aperture system: 100 μm
The number of measured particles: 30000 The volume average particle diameter (Dv) value is the same even when an external additive is externally added to the suspension polymerization toner particles to produce an electrostatic charge image developing toner.

<Method for Measuring “Dv / Dp of Toner Particles”>
Using the above apparatus, the volume average particle diameter (Dv) and the number average particle diameter (Dp) were measured with the above settings to obtain Dv / Dp.
The value of “Dv / Dp” is the same even when an external additive is externally added to the suspension polymerization toner particles to form a toner for developing an electrostatic image.

<Measuring method of “average circularity” of toner particles>
Using the above-mentioned apparatus, the circularity of 30000 suspension-polymerized toner particles was measured with the above settings, and the arithmetic average thereof was taken as “average circularity”.
“Circularity” is a value obtained by dividing the circumference of a circle obtained from the equivalent circle diameter (the diameter of a circle having the same area as the projected area of the particle) by the circumferential length of the projected particle image. If the perimeter of the projected image is L, it is defined as 2 × (π × S) ^1/2 / L.
The value of “average circularity” is the same even when an external additive is externally added to the suspension polymerization toner particles to produce a toner for developing an electrostatic image.

<Measurement method of “color density” (“reflection density”)>
The color density of the solid toner image was substituted and evaluated by the following “reflection density”.
Toner particles (2.0 g) were added to toluene (14 g) and uniformly dissolved and dispersed at room temperature (20 ° C.).
The obtained liquid was applied to a coated paper (OK top coat, manufactured by Oji Paper Co., Ltd.) 150 mm × 100 mm using a bar coater, and the adhesion amount after drying was in the range of 0.1 to 0.6 mg / cm ² . 4 points were changed so as to be applied, and 3 points each were applied (coating area: 100 cm ² ).
It was dried at room temperature (20 ° C.) for 24 hours, and the adhesion amount (mg / cm ² ) after drying was calculated from the change in weight.
For the measurement of “reflection density”, a Macbeth reflection densitometer was used, and the measurement mode: Reflection, filter “NO” was used to measure five “solid portions”, and the arithmetic mean was calculated.
In addition, this “reflection density” is the result of a printing test using a toner for developing electrostatic images obtained by externally adding toner particles with a printer, a copier, etc. If they are the same, we have confirmed separately that the trends are in perfect agreement.

<How to obtain and evaluate "reflection density">
The “reflection density in the range where the adhesion amount after drying is in the range of 0.1 to 0.6 mg / cm ² ” measured above is plotted on the horizontal axis “adhesion amount” and the vertical axis “reflection density”. determine the reflection density at 0.3 mg / cm ² by interpolation to 3 mg / cm ^2, and the "reflection density".

<Method of measuring "acid value" and "amine value">
The acid value was measured according to JIS K2501.
The amine value was measured according to JIS K7237.

<Measuring Method of “Viscosity” of Colored Pigment Dispersion>
It was measured at 25 ° C. using a tuning fork type vibration viscometer (device name: SV-10 (manufactured by A & D)).

Table 3 shows the composition of the color pigment dispersion of the experimental example.

Evaluation results Table 4 shows the evaluation results.

Experimental example No. The toner particles of F09 to F14 have a volume average particle diameter (Dv) larger than 10 μm, but they were not enlarged so that the dispersion state of the color pigment in the color pigment dispersion (toner raw material liquid) was poor. It was found that those having an average pigment abundance ratio of less than 0.6 are inferior in controlling the particle size and shape of the suspended particles.

For toner particles having an average pigment abundance of 0.6 or more, the reflection density at 0.3 mg / cm ² is large, whereas for toner particles having an average pigment abundance of less than 0.6, the “reflection density” (0.3 mg / cm The reflection density at cm ² was small.

It should be noted that “color density” and “reflection” when a solid image was actually printed with a printer, copier, etc. using the toner for developing an electrostatic image obtained by externally adding an external additive to the toner particles of the experimental example. It has been separately confirmed that the “concentration” has the same tendency as well as the absolute values are almost equal if the adhesion amount is unified to 0.3 mg / cm ² .

In the toner particles having a large average pigment abundance, the “reflection density” (reflection density at 0.3 mg / cm ² ) was increased. Moreover, it has been found that both have a certain correlation.
Therefore, when the electrostatic image developing toner of the present invention is used, when a solid image is printed by a printer, a copying machine or the like, a solid image having a high “color density” can be obtained even if the color pigment used for the production is small. I understood that. Generally, when the same coloring density is obtained by reducing the amount of the color pigment used, the image becomes bright.

In the above experimental examples, evaluation was made with toners using carbon black (black color pigment), cyan color pigments, and yellow color pigments as color pigments, but the same applies to color toners of other colors.
In addition, although evaluation was performed using suspension polymerization toner particles, the volume average particle diameter (Dv), the average circularity, and the average pigment abundance ratio of the electrostatic charge image developing toner externally added thereto are the same as those before the external addition. It is the same as the value of toner particles.

Toner particles using the color pigment dispersion for toner particles of the present invention are excellent in dispersibility of the color pigment, shape of the toner particles, particle size distribution, etc., and the pigment can be uniformly distributed in the toner particles. The toner obtained by externally adding an external additive to the toner particles of the invention can be used for a copying machine, a printer, a printing machine, and the like because an excellent color density can be obtained.

Claims

A color pigment dispersion for toner particles containing a color pigment, a dispersant, and a polymerizable vinyl group-containing monomer, wherein the dispersant is formed by trimerization of diisocyanate to form an isocyanurate ring. A colored pigment dispersion for toner particles, wherein an organic group having a repeating unit is bonded to an isocyanate group of an isocyanurate ring-containing compound.
The colored pigment dispersion for toner particles according to claim 1, wherein the isocyanurate ring-containing compound has two or more isocyanurate rings.
The colored pigment dispersion for toner particles according to claim 1, wherein the isocyanurate ring-containing compound has at least one isocyanurate ring formed by trimerization of diisocyanate having an aromatic ring.
The colored pigment dispersion for toner particles according to claim 1, wherein the isocyanurate ring-containing compound is represented by the following formula (1).

[In the formula (1), R 2 represents hydrogen or a branched or unbranched substituted or unsubstituted hydrocarbon group having 1 to 20 carbon atoms, and m represents an integer of 0 or more. ]
The color pigment dispersion for toner particles according to claim 1, wherein the diisocyanate is tolylene diisocyanate.
The colored pigment dispersion for toner particles according to claim 1, wherein the isocyanate group of the isocyanurate ring-containing compound is further bonded with a compound having an active hydrogen-containing group and a tertiary amino group.
The colored pigment dispersion for toner particles according to claim 1, wherein the repeating unit is a polyester chain and / or a polyalkylene glycol chain.
The color pigment dispersion for toner particles according to claim 7, wherein the polyester chain is a polycaprolactone chain.
The colored pigment dispersion for toner particles according to claim 7, wherein the polyalkylene glycol chain is a polypropylene glycol chain.
The color pigment dispersion for toner particles according to claim 1, wherein the number average molecular weight of the repeating unit is 200 to 6000.
2. The color pigment dispersion for toner particles according to claim 1, wherein the acid value of the dispersant is 0 to 30 mg KOH / g.
The colored pigment dispersion for toner particles according to claim 1, wherein the amine value of the dispersant is 0 to 100 mgKOH / g.
2. The color pigment for toner particles according to claim 1, wherein the dispersant is obtained by reacting at least a diisocyanate, an organic group having a repeating unit, and a compound having an active hydrogen-containing group and a tertiary amino group. Dispersion.
The colored pigment dispersion for toner particles according to claim 1, wherein the polymerizable vinyl group-containing monomer is styrene and / or a (meth) acrylate compound.
A method for producing toner particles, comprising: polymerizing the colored pigment dispersion for toner particles according to any one of claims 1 to 14 by suspending or emulsifying in a water-based medium.
A toner for developing an electrostatic image, wherein the toner is obtained using the color pigment dispersion for toner particles according to any one of claims 1 to 14.
15. A toner for developing an electrostatic charge image obtained by using the color pigment dispersion for toner particles according to claim 1, wherein the color pigment is polymerizable in the presence of a dispersant. A color pigment dispersion liquid dispersed in a vinyl group-containing monomer having a heavy bond and a toner raw material liquid containing at least a thermal polymerization initiator in an aqueous inorganic colloid solution have a volume average particle diameter (Dv) of 2 μm or more. An electrostatic image developing toner comprising suspension polymerized toner particles suspended and dispersed so as to have a thickness of 10 μm or less, and then thermally polymerized, in a cross section of one particle of the electrostatic image developing toner An electrostatic charge image developing toner, wherein an average pigment abundance ratio obtained by averaging a pigment abundance ratio is 0.6 or more.
The colored pigment dispersion is mixed with at least a colored pigment, a dispersant, and a vinyl group-containing monomer having a polymerizable double bond, and dispersed using beads having a diameter of 0.01 mm to 5 mm as a dispersion medium. The toner for developing an electrostatic charge image according to claim 17.
The electrostatic charge image developing toner according to claim 17, wherein the suspension polymerization toner particles have an average circularity of 0.95 or more.
18. The method for producing a toner for developing an electrostatic charge image according to claim 17, wherein the color pigment is used in the presence of a dispersant and beads having a diameter of 0.01 mm or more and 5 mm or less are used as a dispersion medium. A colored pigment dispersion is prepared by dispersing in a vinyl group-containing monomer having a bond, and a toner raw material liquid is prepared by blending at least a thermal polymerization initiator in the colored pigment dispersion. Presence of an average pigment characterized in that it comprises a step of suspending and dispersing in a colloidal aqueous solution so that the volume average particle size (Dv) is 2 μm or more and 10 μm or less and then thermally polymerizing to produce suspension polymerized toner particles A method for producing a toner for developing an electrostatic image having a rate of 0.6 or more.