JP7139146B2 - Base resin for colorant masterbatch, colorant masterbatch, method for producing colorant masterbatch, and toner - Google Patents

Description

The present invention relates to a base resin for a colorant masterbatch, a colorant masterbatch, a method for producing a colorant masterbatch, and a toner.

Generally, electrophotography in PPC (Plain Paper Copy) copiers and printers for transferring a toner image formed on a photoreceptor to recording paper is performed in the following procedure. First, an electrostatic latent image is formed on the photoreceptor. Next, the latent image is developed using toner, and after the toner image is transferred onto a sheet to be fixed such as paper, it is heat-fixed with a heat roll or film. In this method, since the toner on the sheet to be fixed is in direct contact with the heat roll or film and the toner is fixed under heat, it is quick and has excellent thermal efficiency. Therefore, fixing efficiency is very good.

So-called pulverization method, polymerization method, and the like are known as methods for producing toner used in such electrophotography. See Patent Documents 1 to 3).

JP 2017-181572 A JP 2017-156563 A Japanese Patent Application Laid-Open No. 2009-210701

According to the studies of the present inventors, there are cases where the colorant masterbatch has poor colorant dispersibility, and even when the colorant masterbatch has excellent colorant dispersibility, fusion of the resulting toner may occur. I found out.

The present invention has been made in view of the above circumstances. Disclosed is a colorant masterbatch that is excellent in dispersibility of the colorant and that can suppress fusion of the resulting toner.

The present inventors have made intensive studies in order to achieve the above objects. As a result, by using a base resin having a storage elastic modulus (G′) at 110° C. within a specific range, a colorant masterbatch that is excellent in colorant dispersibility and capable of suppressing melt-adhesion of the resulting toner is produced. The inventors have found that it can be obtained, and have arrived at the present invention.

That is, according to the present invention, the following base resin for colorant masterbatch, colorant masterbatch, method for producing the colorant masterbatch, and toner are provided.

[1]
The base resin used in a toner colorant masterbatch containing a colorant and a base resin,
The base resin includes a vinyl resin,
A colorant masterbatch base having a storage elastic modulus (G') of 10 Pa or more and 10,000 Pa or less at 110°C, which is obtained by dynamic viscoelasticity measurement under conditions of a frequency of 1 Hz, a swing angle of γ1%, and a measurement temperature of 110°C. resin.
[2]
In the base resin for a colorant masterbatch according to [1] above,
A base resin for a colorant masterbatch having a weight average molecular weight of 100,000 or less in terms of monodisperse standard polystyrene, as determined by gel permeation chromatography.
[3]
In the base resin for a colorant masterbatch according to [1] or [2] above,
A base resin for a colorant masterbatch, wherein the vinyl resin contains a styrene polymer.
[4]
In the base resin for the colorant masterbatch according to [3] above,
A base resin for a colorant masterbatch, wherein the styrenic polymer comprises at least one selected from polystyrene and a styrene/(meth)acrylic copolymer.
[5]
In the base resin for a colorant masterbatch according to any one of [1] to [4] above,
A base resin for a colorant masterbatch having a glass transition temperature (Tg) of 30° C. or higher and 80° C. or lower as measured by a differential scanning calorimeter (DSC).
[6]
A colorant masterbatch comprising the base resin for a colorant masterbatch according to any one of [1] to [5] above and a colorant.
[7]
In the colorant masterbatch described in [6] above,
The ratio (Y/X) of the content (Y) of the colorant to the content (X) of the base resin for the colorant masterbatch in the colorant masterbatch is 10/90 or more and 90/10 or less by mass. colorant masterbatch.
[8]
A production method for producing the colorant masterbatch according to [6] or [7] above,
A method for producing a colorant masterbatch, comprising the step of kneading a mixture of the colorant masterbatch base resin and the colorant at a temperature of 80°C or higher and 150°C or lower.
[9]
A toner comprising the colorant masterbatch according to [6] or [7] above and a binder resin.
[10]
In the toner described in [9] above,
A toner in which the binder resin contains a styrene/(meth)acrylic copolymer.
[11]
The toner according to the above [9] or [10], which is for electrophotography.

According to the present invention, a base resin for a colorant masterbatch capable of realizing a colorant masterbatch having excellent colorant dispersibility and capable of suppressing fusion of the resulting toner, and a colorant excellent in dispersibility, and Thus, it is possible to provide a colorant masterbatch capable of suppressing fusion of the resulting toner.

Embodiments of the present invention are described below. The numerical range "A to B" represents from A to B unless otherwise specified. Moreover, in the present embodiment, the term "polymerization" may be used to mean copolymerization, and the term "polymer" may be used to mean copolymer.

[Base resin for colorant masterbatch]
The base resin for the colorant masterbatch according to this embodiment will be described below.
A base resin for a colorant masterbatch according to the present embodiment (hereinafter also referred to as a base resin) is a base resin used in a colorant masterbatch for a toner containing a colorant and a base resin, and the base resin is a vinyl resin. The storage elastic modulus (G') at 110°C obtained by dynamic viscoelasticity measurement under conditions of a frequency of 1 Hz, an oscillation angle of γ of 1%, and a measurement temperature of 110°C is from the viewpoint of suppressing fusion of the resulting toner. Therefore, it is 10 Pa or more, preferably 15 Pa or more, and from the viewpoint of improving the dispersibility of the colorant in the resulting colorant masterbatch, it is 10,000 Pa or less, preferably 4,500 Pa or less, more preferably 3,000 Pa. Below, more preferably 2,500 Pa or less.

As described above, according to the studies of the present inventors, when the colorant masterbatch is poor in dispersibility of the colorant, or even when the dispersibility of the colorant is excellent, fusion of the obtained toner occurs. I found out that there is a case where the
Here, a polyester-based resin is mainly used as the base resin of the toner. Toner production methods include a polymerization method and a pulverization method. The polymerization method involves many production steps and requires a high production cost. On the other hand, the pulverization method is excellent in productivity because it requires few manufacturing steps. However, polyester resins are difficult to pulverize. In contrast, vinyl resins are easy to pulverize. As a pulverization method, a method of producing a masterbatch of a coloring agent and a resin is known. If the colorant is present in the colorant masterbatch with good dispersibility, the colorant can be well dispersed in the toner. However, if the dispersibility of the colorant in the colorant masterbatch is poor, the hue of the printed image will be shifted when the toner is used for printing.
The pulverization method includes a method in which a colorant masterbatch and a binder resin are mixed and then pulverized, and a method in which a colorant and a binder resin are mixed, kneaded and then pulverized. The method of using a colorant masterbatch allows the colorant to be even more dispersed. When a vinyl resin is used as the binder resin, the base resin for the colorant masterbatch is also preferably a vinyl resin. However, when a vinyl resin is used as a base resin for a colorant masterbatch, it may be difficult to mix the colorant with good dispersibility. In particular, in the case of a color toner using a colorant other than a black colorant (such as carbon black), it is required to mix the colorant with even better dispersibility in order to match the hue of the printed image with the design.

The present inventors have made intensive studies in order to achieve the above objects. As a result, by using a base resin having a storage elastic modulus (G′) at 110° C. within the above range, a colorant masterbatch having excellent colorant dispersibility and capable of suppressing fusion of the resulting toner can be obtained. I found out that it can be done.
That is, the base resin for the colorant masterbatch according to the present embodiment has a storage elastic modulus (G′) at 110° C. within the above range, so that the colorant is excellent in dispersibility and the resulting toner melts. A colorant masterbatch capable of suppressing adhesion can be realized.
Although the reason for this is not necessarily clear, if the storage elastic modulus (G′) at 110° C. of the base resin for the colorant masterbatch according to the present embodiment is equal to or less than the above upper limit value, the base resin for the colorant masterbatch and It is believed that when the colorant is kneaded, the viscosity of the kneaded product becomes low and the aggregates of the colorant are easily broken, resulting in good dispersibility of the colorant in the resulting colorant masterbatch. Further, when the storage elastic modulus (G′) at 110° C. of the base resin for the colorant masterbatch according to the present embodiment is equal to or higher than the above lower limit, the colorant masterbatch containing the base resin and the colorant and the binder resin are less likely to soften when mixed with each other, and the resulting toner powders are prevented from sticking to each other due to the heat generated in the pulverization process, and as a result, it is thought that the fusion of the resulting toner can be suppressed.
Therefore, according to the base resin for a colorant masterbatch according to the present embodiment, the storage elastic modulus (G′) at 110° C. is within the above range, so that the colorant is excellent in dispersibility and can be obtained. It is believed that a colorant masterbatch capable of suppressing fusion of toner can be realized.
Further, since the colorant masterbatch obtained using the base resin for the colorant masterbatch according to the present embodiment has excellent dispersibility of the colorant, the dispersibility of the colorant in the resulting toner is improved. be able to. Therefore, according to the toner using the base resin for the colorant masterbatch according to the present embodiment, it is possible to reduce the deviation between the hue of the printed image and the designed hue and to improve the anti-offset property. .

The base resin according to the present embodiment includes a vinyl resin because it can improve the various properties required for the toner in a well-balanced manner, the resulting toner has excellent pulverizability, and the productivity of the toner can be improved. . Here, the vinyl resin in this embodiment refers to a resin obtained by polymerizing a vinyl compound as a monomer.

In the present embodiment, for example, by adjusting the weight average molecular weight and glass transition temperature of the base resin for the colorant masterbatch, the types of monomers constituting the base resin for the colorant masterbatch, their content ratios, and the like, , the storage elastic modulus (G') at 110°C of the base resin for the colorant masterbatch can be controlled within the above range.

In the base resin for the colorant masterbatch according to the present embodiment, the upper limit of the weight average molecular weight in terms of monodisperse standard polystyrene obtained by gel permeation chromatography is preferably 100,000 or less, and 60,000 or less. is preferably 40,000 or less, and particularly preferably 20,000 or less. The lower limit of the weight average molecular weight is preferably 1,000 or more, more preferably 2,000 or more.
When the weight average molecular weight of the base resin for the colorant masterbatch is within the above range, it becomes easy to adjust the storage modulus (G') of the base resin for the colorant masterbatch at 110°C within the above range.

In the colorant masterbatch base resin according to the present embodiment, the glass transition temperature (Tg) measured by a differential scanning calorimeter (DSC) is preferably 30° C. or higher and 80° C. or lower, and 40° C. or higher and 65° C. It is more preferably 42° C. or higher and 58° C. or lower. When the glass transition temperature of the base resin is at least the above lower limit, aggregation of the colorant during transportation, storage, and during the toner manufacturing process can be further suppressed.
If the glass transition temperature of the base resin is equal to or lower than the above upper limit, when the colorant masterbatch is mixed with the binder resin to form a toner, the fixability of the toner is further improved.

The vinyl resin according to the present embodiment is preferably a styrene-based polymer containing a styrene-based monomer as a monomer, from the viewpoint of improving various properties required for the toner in a well-balanced manner. Polystyrene and styrene-(meth) At least one styrenic polymer selected from acrylic copolymers is more preferable.

The styrene/(meth)acrylic copolymer according to the present embodiment is a resin containing a styrene monomer and a (meth)acrylic monomer as constituent monomers, and at least one styrene monomer. obtained by using a known polymerization method using a polymer and at least one (meth)acrylic monomer. Further, the styrene/(meth)acrylic copolymer according to the present embodiment is a resin containing a styrene-based monomer, a (meth)acrylic monomer and a carboxyl group-containing monomer as constituent monomers. , at least one styrenic monomer, at least one (meth)acrylic monomer, and at least one carboxyl group-containing monomer obtained by using a known polymerization method It may be a polymer.

In the styrene/(meth)acrylic copolymer according to the present embodiment, the content of the styrene monomer is 50% by mass when the entire styrene/(meth)acrylic copolymer is 100% by mass. It is preferably at least 100% by mass, more preferably from 55% by mass to 99% by mass, and even more preferably from 60% by mass to 97% by mass.
In the styrene/(meth)acrylic copolymer according to the present embodiment, the content of the (meth)acrylic monomer is 100% by mass of the entire styrene/(meth)acrylic copolymer. At this time, it is preferably more than 0% by mass and 50% by mass or less, more preferably 0.5% by mass or more and 40% by mass or less, and even more preferably 2% by mass or more and 35% by mass or less.
In the styrene/(meth)acrylic copolymer according to the present embodiment, the content of the carboxyl group-containing monomer is 100% by mass of the entire styrene/(meth)acrylic copolymer. 0% by mass or more and 15% by mass or less is preferable, and 0% by mass or more and 10% by mass or less is more preferable.

Here, examples of styrene-based monomers according to the present embodiment include styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, p- Examples include n-nonylstyrene, pn-decylstyrene and pn-dodecylstyrene. Among these, styrene is preferred.

Examples of (meth)acrylic monomers according to the present embodiment include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, cyclohexyl acrylate, stearyl acrylate, benzyl acrylate, Acrylic esters such as furfuryl acrylate, hydroxyethyl acrylate, hydroxybutyl acrylate, dimethylaminomethyl acrylate, dimethylaminoethyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, methacrylic acid Octyl, cyclohexyl methacrylate, stearyl methacrylate, benzyl methacrylate, furfuryl methacrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate, dimethylaminomethyl methacrylate, methacrylic acid esters such as dimethylaminoethyl methacrylate; acrylamide, methacrylamide , N-substituted acrylamide and N-substituted methacrylamide; acrylonitrile, methacrylonitrile and the like. Among these, acrylic acid esters, methacrylic acid esters, acrylonitrile and methacrylonitrile are preferred, and butyl acrylate, methyl methacrylate, butyl methacrylate and hydroxyethyl acrylate are more preferred.

Examples of the carboxyl group-containing monomer according to the present embodiment include acrylic acid, methacrylic acid, maleic anhydride, maleic acid, fumaric acid, cinnamic acid, methyl fumarate, ethyl fumarate, propyl fumarate, and butyl fumarate. , octyl fumarate, methyl maleate, ethyl maleate, propyl maleate, butyl maleate, monoesters of unsaturated dibasic acids such as octyl maleate. Among these, acrylic acid, methacrylic acid, fumaric acid, methyl fumarate, ethyl fumarate, propyl fumarate, butyl fumarate and octyl fumarate are preferred, and acrylic acid and methacrylic acid are particularly preferred.

The styrene/(meth)acrylic copolymer according to the present embodiment contains the above-mentioned monomers, as well as inorganic compounds such as dimethyl fumarate, dibutyl fumarate, dioctyl fumarate, dimethyl maleate, dibutyl maleate, and dioctyl maleate. Diesters of saturated diacids can also be used as monomers.

In the present embodiment, known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, and combinations thereof can be employed as the method for producing the vinyl resin. Solution polymerization is preferably adopted because it is easy to adjust the molecular weight distribution.

Solvents used in solution polymerization include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene and cumene, and these may be used alone or in mixtures thereof, preferably xylene.

Polymerization may be performed using a polymerization initiator, or so-called thermal polymerization may be performed without using a polymerization initiator. As the polymerization initiator, one that can be used as a radical polymerization initiator can be used. For example 2,2′-azobisisobutyronitrile, 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2′-azobisisobutyrate, 1,1′ -azobis(1-cyclohexanecarbonitrile), 2-(carbamoylazo)-isobutyronitrile, 2,2'-azobis(2,4,4-trimethylpentane), 2-phenylazo-2,4-dimethyl-4- azo initiators such as methoxyvaleronitrile and 2,2′-azobis(2-methyl-propane); ketone peroxides such as methyl ethyl ketone peroxide, acetylacetone peroxide and cyclohexanone peroxide; 1,1-bis(t- butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane and other peroxyketals; t-butyl hydro Hydroperoxides such as peroxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide; di-t-butyl peroxide, t-butylcumyl peroxide, di-cumyl peroxide, Dialkyl peroxides such as 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and α,α'-bis(t-butylperoxyisopropyl)benzene; oxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, diacyl peroxides such as m-toluoyl peroxide; di-isopropyl peroxydicarbonate, di- 2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate, di-methoxyisopropyl peroxydicarbonate, di(3-methyl-3-methoxybutyl)peroxydicarbonate peroxydicarbonates such as oxydicarbonate; sulfonyl peroxides such as acetylcyclohexylsulfonyl peroxide; t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, kumi Ruperoxyneodecanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxylaure Peroxyesters such as tri-, t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, di-t-butyldiperoxyisophthalate, and the like can be exemplified. These initiators may be used alone or in combination of two or more.

The type and amount of the polymerization initiator can be appropriately selected depending on the reaction temperature, monomer concentration, etc., and is usually used in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the monomer used.

[Colorant Masterbatch]
Next, the colorant masterbatch according to this embodiment will be described.
The colorant masterbatch according to the present embodiment includes a colorant masterbatch base resin and a colorant.

The ratio (Y/X) of the content (Y) of the colorant to the content (X) of the base resin for the colorant masterbatch in the colorant masterbatch is not particularly limited. From the viewpoint of suppressing aggregation of the agent, the mass ratio is preferably 10/90 or more and 90/10 or less, preferably 25/75 or more and 85/15 or less, and 40/60 or more and 75/25 or less. more preferably 40/60 or more and 65/35 or less.
The colorant masterbatch according to the present embodiment uses the base resin for the colorant masterbatch according to the present embodiment as the base resin, thereby maintaining good dispersibility of the colorant even when the content of the colorant is increased. be able to.

Conventionally known pigments and dyes can be used as the colorant.
Examples of pigments include Mineral Fast Yellow, Navel Yellow, Naphthol Yellow S, Hansa Yellow G, Permanent Yellow NCG, Tartrazine Lake, Molybdenum Orange, Permanent Orange GTR, Pyrazolone Orange, Benzidine Orange G, Permanent Red 4R, and Watching Red. Calcium salt, eosin lake, brilliant carmine 3B, manganese purple, fast violet B, methyl violet lake, cobalt blue, alkali blue lake, victoria blue lake, phthalocyanine blue, fast sky blue, indanthrene blue BC, chrome green, pigment green B, Malachite Green Lake, Final Yellow Green G, and the like. Coloring pigments for magenta include 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, 49, 50, 51, 52, 53, 54, 55, 57, 58, 60, 63, 64, 68, 81, 83, 87, 88, 89, 90, 112, 114, 122, 123, 163, 202, 206, 207, 209, 238, C.I. I. Pigment Violet 19, C.I. I. Butt Red 1, 2, 10, 13, 15, 23, 29, 35 and the like. As a cyan coloring pigment, C.I. I. Pigment Blue 2, 3, 15, 15:1, 15:2, 15:3, 16, 17, C.I. I. Acid Blue 6, C.I. I. Examples thereof include Acid Blue 45 and copper phthalocyanine pigments having a phthalocyanine skeleton substituted with 1 to 5 phthalimidomethyl groups. As a coloring pigment for yellow, C.I. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 15, 16, 17, 23, 65, 73, 74, 83, 93, 97, 155, 180, 185, C.I. I. Bat Yellow 1, 3, 20 and the like. Black pigments include carbon black such as furnace black, channel black, acetylene black, thermal black and lamp black. As a dye, C.I. I. Direct Red 1, C.I. I. Direct Red 4, C.I. I. Acid Red 1, C.I. I. Basic Red 1, C.I. I. Mordan Tread 30, C.I. I. Direct Blue 1, C.I. I. Direct Blue 2, C.I. I. Acid Blue 9, C.I. I. Acid Blue 15, C.I. I. Basic Blue 3, C.I. I. Basic Blue 5, C.I. I. Mordant Blue 7, C.I. I. Direct Green 6, C.I. I. Basic Green 4, C.I. I. Basic Green 6, Solvent Yellow 162, and the like.
These colorants may be used alone or in combination of two or more. Among these, pigments are preferable as the colorant.

[Manufacturing method of colorant masterbatch]
Next, an example of a method for producing a colorant masterbatch according to this embodiment will be described.
As an example of the method for producing the colorant masterbatch according to the present embodiment, there is a method of kneading a base resin for a colorant masterbatch and a colorant.

As such a method, for example, a method of charging a base resin for a colorant masterbatch and a colorant into a batch-type kneader such as a twin-screw kneader, an open-roll kneader, and a pressure kneader and kneading them while heating can be adopted.
Further, after obtaining the kneaded product, it is preferable to further knead it with a three-roll mill or the like. This can effectively break up colorant agglomerates in the colorant masterbatch, resulting in better dispersion of the colorant in the colorant masterbatch.

The temperature at which the mixture containing the base resin for the colorant masterbatch and the colorant is kneaded is not particularly limited because it varies depending on the molecular weight of the base resin for the colorant masterbatch, but is preferably 80° C. or higher and 150° C. or lower, and 80° C. or higher. 130° C. is more preferable, and 100° C. or more and 130° C. or less is particularly preferable. By setting the kneading temperature to the above lower limit or more, the shear applied to the kneaded product becomes appropriate, and the colorant can be dispersed more favorably in the colorant masterbatch.
By keeping the kneading temperature at or below the above upper limit, it is possible to reduce the decomposition of the colorant, resulting in fading or discoloration.

[toner]
Next, the toner according to this embodiment will be described.

The toner according to this embodiment includes the colorant masterbatch according to this embodiment and a binder resin. Furthermore, one or more selected from release agents, charge control agents, magnetic substances, binder resins, resins other than base resins for colorant masterbatch, and surface treatment agents may be further included.

<Binder resin>
The binder resin according to the present embodiment preferably contains at least one selected from styrene/(meth)acrylic copolymers and polyester resins from the viewpoint of improving the various properties required for the toner in a well-balanced manner. It is more preferable to contain a styrene/(meth)acrylic copolymer in terms of pulverizability of the toner, stability in a charged environment, dispersibility of the release agent, storage stability, and resistance to contamination of the photoreceptor.
Further, the binder resin according to the present embodiment may be the same type of resin as the base resin for the colorant masterbatch, or may be a different type of resin. The binder resin according to the present embodiment is the same type of resin as the base resin for the colorant masterbatch, since compatibility with the base resin is improved and the state of dispersion of the colorant in the toner is further improved. More preferably, both the binder resin and the colorant masterbatch base resin according to the present embodiment are vinyl resins.

The styrene/(meth)acrylic copolymer is a resin containing a styrene monomer and a (meth)acrylic monomer as constituent monomers, and is composed of at least one styrene monomer and at least one It is obtained by using a known polymerization method using a (meth)acrylic monomer.

Here, examples of styrene-based monomers according to the present embodiment include styrene, p-methylstyrene, m-methylstyrene, o-methylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, 3,4-dichlorostyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn-hexylstyrene, pn-octylstyrene, p- Examples include n-nonylstyrene, pn-decylstyrene and pn-dodecylstyrene. Among these, styrene is preferred.

Examples of (meth)acrylic monomers according to the present embodiment include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, octyl acrylate, cyclohexyl acrylate, stearyl acrylate, benzyl acrylate, Acrylic esters such as furfuryl acrylate, hydroxyethyl acrylate, hydroxybutyl acrylate, dimethylaminomethyl acrylate, dimethylaminoethyl acrylate; methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, methacrylic acid Octyl, cyclohexyl methacrylate, stearyl methacrylate, benzyl methacrylate, furfuryl methacrylate, hydroxyethyl methacrylate, hydroxybutyl methacrylate, dimethylaminomethyl methacrylate, methacrylic acid esters such as dimethylaminoethyl methacrylate; acrylamide, methacrylamide , N-substituted acrylamide and N-substituted methacrylamide; acrylonitrile, methacrylonitrile and the like. Among these, acrylic acid esters, methacrylic acid esters, acrylonitrile and methacrylonitrile are preferred, and butyl acrylate, methyl methacrylate, butyl methacrylate and hydroxyethyl acrylate are more preferred.

In the present embodiment, in addition to the above monomers, diesters of unsaturated dibasic acids such as dimethyl fumarate, dibutyl fumarate, dioctyl fumarate, dimethyl maleate, dibutyl maleate, and dioctyl maleate are also used as monomers. can be used.

The polyester-based resin is not particularly limited, but for example, a known polyester-based resin generally used as a binder resin for toner can be used.

When the styrene/(meth)acrylic copolymer is composed of a high molecular weight styrene/(meth)acrylic copolymer (H) and a low molecular weight styrene/(meth)acrylic copolymer (L), the ratio (H/L) is preferably 10/90 to 90/10, more preferably 20/80 to 80/20, from the viewpoint of overall balance of toner fixability, offset resistance, durability, and the like. more preferred.
By setting the ratio of the high-molecular-weight styrene/(meth)acrylic copolymer (H) to the lower limit or more, a toner having excellent durability and offset resistance can be obtained. Further, by setting the ratio of the high-molecular-weight styrene/(meth)acrylic copolymer (H) to the above upper limit or less, a toner having excellent fixability and productivity can be obtained.

(High molecular weight styrene/(meth)acrylic copolymer (H))
In the present embodiment, the high-molecular-weight vinyl resin (H) may have a main peak in the molecular weight region of 5.0×10 ⁴ or more and 5.0×10 ⁵ or less in the molecular weight distribution in which the THF-soluble content is measured by GPC. It is preferable to have a peak at 1.0×10 ⁵ or more and 3.5×10 ⁵ or less in order to achieve a good balance among fixability, anti-offset property and durability.
By setting the molecular weight of the main peak of the high-molecular-weight styrene-(meth)acrylic copolymer (H) (hereinafter referred to as the peak molecular weight) to the above lower limit or more, the strength of the resin is improved and the toner is excellent in durability. can be obtained. Further, by setting the peak molecular weight to the above upper limit or less, even if the high-molecular-weight vinyl resin remains in an unreacted state, the viscosity of the toner during fixing does not easily increase, and a toner having excellent fixability can be obtained. In addition, the strength of the resin is moderate, and the toner can be produced with excellent productivity.

The high-molecular-weight styrene/(meth)acrylic copolymer (H) is not necessarily a single polymer, and two or more high-molecular-weight styrene/(meth)acrylic copolymers may be used. . In that case, it is preferable that the high-molecular-weight styrene/(meth)acrylic copolymer (H) as a whole satisfies the above properties. Moreover, when producing a single polymer, it is possible to add a styrene-based monomer or a (meth)acrylic-based monomer during the polymerization, or to add it separately at the initial stage and the late stage of the polymerization.

(Low molecular weight styrene/(meth)acrylic copolymer (L))
In the present embodiment, the low-molecular-weight styrene/(meth)acrylic copolymer (L) has a molecular weight of 1.0×10 ³ or more and less than 5.0×10 ⁴ in the molecular weight distribution measured by GPC for the THF-soluble content. It preferably has a main peak, and more preferably has a main peak at a molecular weight of 2.0×10 ³ or more and 3.0×10 ⁴ or less from the viewpoint of fixability, durability, and toner productivity. By making the peak molecular weight equal to or higher than the above lower limit, the toner can be made more excellent in durability. By setting the peak molecular weight to be equal to or less than the upper limit, the toner can be made excellent in fixability and productivity.

The low-molecular-weight styrene/(meth)acrylic copolymer (L) is not necessarily a single polymer, and two or more types of low-molecular-weight styrene/(meth)acrylic copolymers may be used. do not have. In that case, the low-molecular-weight styrene/(meth)acrylic copolymer (L) as a whole preferably satisfies the above properties. Moreover, when producing a single polymer, it is possible to add a styrene-based monomer or a (meth)acrylic-based monomer during the polymerization, or to add it separately at the initial stage and the late stage of the polymerization.

In the present embodiment, known polymerization methods such as solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, and combinations thereof can be employed as the method for producing the styrene/(meth)acrylic copolymer. Solution polymerization is preferably employed in terms of adjustment of the molecular weight distribution and miscibility of the high-molecular-weight styrene/(meth)acrylic copolymer (H) and the low-molecular-weight styrene/(meth)acrylic copolymer (L).

The styrene/(meth)acrylic copolymer according to the present embodiment comprises a high-molecular-weight styrene/(meth)acrylic copolymer (H) and a low-molecular-weight styrene/(meth)acrylic copolymer (L), They can be obtained by polymerizing each of them independently in advance and mixing them in a molten state or a solution state. Further, after polymerizing either the high-molecular-weight styrene/(meth)acrylic copolymer (H) or the low-molecular-weight styrene/(meth)acrylic copolymer (L) alone, the styrene/(meth)acrylic copolymer It can also be obtained by polymerizing the other styrene/(meth)acrylic copolymer in the presence of the copolymer.

Solvents used in solution polymerization include aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene and cumene, and these may be used alone or in mixtures thereof, preferably xylene.

Polymerization may be performed using a polymerization initiator, or so-called thermal polymerization may be performed without using a polymerization initiator. As the polymerization initiator, one that can be used as a radical polymerization initiator can be used. For example 2,2′-azobisisobutyronitrile, 2,2′-azobis(4-methoxy-2,4-dimethylvaleronitrile), dimethyl-2,2′-azobisisobutyrate, 1,1′ -azobis(1-cyclohexanecarbonitrile), 2-(carbamoylazo)-isobutyronitrile, 2,2'-azobis(2,4,4-trimethylpentane), 2-phenylazo-2,4-dimethyl-4- azo initiators such as methoxyvaleronitrile and 2,2′-azobis(2-methyl-propane); ketone peroxides such as methyl ethyl ketone peroxide, acetylacetone peroxide and cyclohexanone peroxide; 1,1-bis(t- butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane and other peroxyketals; t-butyl hydro Hydroperoxides such as peroxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide; di-t-butyl peroxide, t-butylcumyl peroxide, di-cumyl peroxide, Dialkyl peroxides such as 2,5-dimethyl-2,5-di(t-butylperoxy)hexane and α,α'-bis(t-butylperoxyisopropyl)benzene; oxide, decanoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, benzoyl peroxide, diacyl peroxides such as m-toluoyl peroxide; di-isopropyl peroxydicarbonate, di- 2-ethylhexyl peroxydicarbonate, di-n-propyl peroxydicarbonate, di-2-ethoxyethyl peroxydicarbonate, di-methoxyisopropyl peroxydicarbonate, di(3-methyl-3-methoxybutyl)peroxydicarbonate peroxydicarbonates such as oxydicarbonate; sulfonyl peroxides such as acetylcyclohexylsulfonyl peroxide; t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butyl peroxyneodecanoate, kumi Ruperoxyneodecanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxylaure Peroxyesters such as tri-, t-butylperoxybenzoate, t-butylperoxyisopropyl carbonate, di-t-butyldiperoxyisophthalate, and the like can be exemplified. These initiators may be used alone or in combination of two or more.

The type and amount of the polymerization initiator can be appropriately selected depending on the reaction temperature, monomer concentration, etc., and is usually used in an amount of 0.01 to 10 parts by weight per 100 parts by weight of the monomer used.

A styrene/(meth)acrylic copolymer is a block copolymer consisting of a block consisting of a chain of constitutional units derived from an ethylene hydrocarbon and/or a conjugated diene hydrocarbon and a block consisting of a chain derived from styrene, and at least one selected from hydrogenated block copolymers which are hydrogenated products thereof.

The content of these block copolymers and hydrogenated block copolymers is preferably 0.05 parts by mass or more and 1.5 parts by mass or less with respect to 100 parts by mass of the styrene/(meth)acrylic copolymer. and more preferably 0.1 parts by mass or more and 1.0 parts by mass or less.

To obtain these block copolymers, generally ethylene, propylene, 1-butene, 2-butene, isobutylene, 1-pentene, 2-pentene, 2-methyl-1-butene, 3-methyl-1-butene , 2-methyl-2-butene, 1-hexene, 2,3-dimethyl-2-butene, etc., and conjugated diene hydrocarbons such as butadiene and isoprene. you can These are produced by a method such as utilizing a reactive group of a block copolymer produced by known living anionic polymerization or living cationic polymerization, and then blocking styrene. However, the manufacturing method is not subject to any limitation, and those manufactured by other conventionally known manufacturing methods may be used. Furthermore, some of the above block copolymers have unsaturated double bonds. These may be used as hydrogenated products by reacting unsaturated double bonds with hydrogen by a known method.

Examples of the above block copolymer include commercially available products such as Kraton (styrene-ethylene/butylene-styrene block copolymer (SEBS), styrene-butadiene-styrene block copolymer, styrene-isoprene- styrene-based block copolymer, styrene-ethylene/propylene-styrene-based block copolymer, styrene-ethylene/propylene-based block copolymer), Septon manufactured by Kuraray Co., Ltd. (styrene-ethylene/propylene-based block copolymer, styrene -hydrogenated isoprene-based block copolymer), Tuffprene manufactured by Asahi Kasei Corporation (styrene-butadiene-based block copolymer), and the like.

(polyester resin)
Although the polyester-based resin used as the binder resin according to the present embodiment is not particularly limited, polyester-based resins generally used as binder resins for toners are preferable.
As the polyester resin, for example, one obtained by polycondensation or cocondensation of an alcohol component and a carboxylic acid component can be used. Examples of alcohol components and carboxylic acid components include the following.

Examples of alcohol components include bisphenols such as bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, and polyoxypropylenated bisphenol A; ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3 - propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4-butenediol, 1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimethanol, dipropylene glycol, polyethylene glycol. , polypropylene glycol, diols such as polytetramethylene glycol; sorbitol, 1,2,3,6-hexanetetrol, 1,4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, 1,2,4- butanetriol, 1,2,5-pentanetriol, glycerol, diglycerol, 2-methylpropanetriol, 2-methyl-1,2,4-butanetriol, trimethylolethane, trimethylolpropane, 1,3,5- Dihydric or trihydric or higher alcohols such as trihydroxymethylbenzene are included.

Carboxylic acid components include maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, azelaic acid, malonic acid, n -butyl succinic acid, n-butenyl succinic acid, isobutyl succinic acid, isobutenyl succinic acid, n-octyl succinic acid, n-octenyl succinic acid, n-dodecyl succinic acid, n-dodecenyl succinic acid, isododecyl succinic acid, isododecenyl Divalent carboxylic acids such as succinic acid; 1,2,4-benzenetricarboxylic acid (trimellitic acid), 1,2,5-benzenetricarboxylic acid, 2,5,7-naphthalenetricarboxylic acid, 1,2,4 -naphthalenetricarboxylic acid, 1,2,4-butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, 1,2,4-cyclohexanetricarboxylic acid acid, tetra(methylenecarboxyl)methane, 1,2,7,8-octanetetracarboxylic acid, pyromellitic acid, carboxylic acid having a valence of 3 or higher such as empol trimer acid, and the like.
Acid anhydrides or lower alkyl esters of these carboxylic acids can also be used.

The toner according to the exemplary embodiment may further contain a releasing agent in order to exhibit better fixing performance and anti-offset performance.
Conventionally known release agents can be used. For example, low molecular weight polyethylene, low molecular weight polypropylene, polyolefin copolymer, polyolefin wax, paraffin wax, microcrystalline wax, aliphatic hydrocarbon wax such as Fischer-Tropsch wax; aliphatic hydrocarbon wax such as oxidized polyethylene wax; vegetable waxes such as candelilla wax, carnauba wax, Japan wax, rice wax and jojoba wax; animal waxes such as beeswax, lanolin and spermaceti; mineral waxes such as ozokerite, ceresin and petrolatum; Waxes based on fatty acid esters, such as montanic acid esters and castor wax; waxes obtained by partially or wholly deoxidizing fatty acid esters, such as deoxidized carnauba wax; palmitic, stearic, montanic, or longer saturated straight chain fatty acids such as long chain alkyl carboxylic acids with chain alkyl groups; unsaturated fatty acids such as brassic acid, eleostearic acid, parinaric acid; stearyl alcohol, eicosyl alcohol, behenyl alcohol, carnauvyl alcohol, Saturated alcohols such as ceryl alcohol, melicyl alcohol, or long chain alkyl alcohols with longer alkyl groups; polyhydric alcohols such as sorbitol; fatty acid amides such as linoleic acid amide, oleic acid amide, lauric acid amide. saturated fatty acid bisamides such as methylenebisstearic acid amide, ethylenebiscapric acid amide, ethylenebislauric acid amide, hexamethylenebisstearic acid amide; unsaturated fatty acid amides such as dioleyladipate and N,N'-dioleylsebacamide; aromatic bisamides such as m-xylenebisstearate and N,N'-distearylisophthalamide; An aliphatic hydrocarbon wax is grafted with a vinyl monomer such as a styrene monomer, a (meth)acrylic monomer, a carboxyl group-containing monomer, or a glycidyl group-containing monomer. Waxes; partial esters of aliphatic and polyhydric alcohols such as behenic acid monoglyceride; methyl ester compounds having hydroxyl groups obtained by hydrogenating vegetable oils; polyethylene, polypropylene, polybutene synthesized by metallocene catalysts; poly pen Thene, polyhexene, polyheptene, polyoctene, ethylene-propylene copolymer, ethylene-butene copolymer, butene-propylene copolymer, condensation of long-chain alkylcarboxylic acid and polyhydric alcohol, and halogen of long-chain alkylcarboxylic acid and ester group-containing wax obtained by reacting a compound with a polyhydric alcohol. Further examples include waxes having functional groups such as hydroxyl groups, ester groups and carboxyl groups.
These release agents may be used alone or in combination of two or more.

In the present embodiment, the content of the release agent is preferably 1 part by mass or more and 10 parts by mass or less with respect to a total of 100 parts by mass of the binder resin and the base resin, from the viewpoint of the balance between offset resistance and storage stability. 2 parts by mass or more and 8 parts by mass or less is more preferable. When the content of the release agent is at least the above lower limit, a toner having excellent anti-offset properties can be obtained. can be suppressed. In addition, since the release agent is less likely to be unevenly distributed, the release agent can be prevented from coming off from the toner, and the toner can have excellent durability.

The content of the colorant in the toner is preferably 0.05 to 20 parts by weight, more preferably 0.1 to 15 parts by weight, and still more preferably 0.05 to 20 parts by weight, based on a total of 100 parts by weight of the binder resin and the base resin. 2 to 10 parts by mass.
Further, the colorant may be separately contained in the toner in addition to the colorant in the colorant masterbatch.
In addition, the content of the colorant masterbatch in the toner is appropriately adjusted so that the content of the colorant in the toner is within a preferred range.

A magnetic substance can also be used as an alternative to the coloring agent. Examples of magnetic substances include metal oxides containing elements such as iron, cobalt, nickel, copper, magnesium, manganese, aluminum, and silicon. Yttrium iron oxide, cadmium iron oxide, gadolinium iron oxide, copper oxide iron, lead iron oxide, nickel iron oxide, neodymium iron oxide, barium iron oxide, magnesium iron oxide, manganese iron oxide, lanthanum iron oxide, iron powder, cobalt powder, Nickel powder etc. are mentioned. You may use these magnetic bodies in combination of 2 or more types as needed. As for the shape, it is preferable to use a spherical, octahedral, or hexahedral shape, and it is more preferable to use a spherical shape in order to uniformly disperse the magnetic material in the toner.

The content of the magnetic substance is preferably 4 to 200 parts by mass, more preferably 10 to 170 parts by mass, still more preferably 20 to 150 parts by mass, based on 100 parts by mass of the binder resin and the base resin.

In addition, the toner according to the present embodiment may include, for example, polyvinyl chloride, polyvinyl acetate, polyester, polyvinyl butyral, polyurethane, polyamide, polystyrene, rosin, and polymerized rosin, as long as the effects of the present embodiment are not hindered. , modified rosin, terpene resin, phenolic resin, aromatic petroleum resin, vinyl chloride resin, styrene-butadiene resin, styrene-(meth)acrylic copolymer, chroman-indene resin, melamine resin, etc. You may

The toner according to the exemplary embodiment may contain a charge control agent to maintain positive or negative chargeability. Conventionally known charge control agents can be used.
Positive charge control agents include, for example, nigrosine and modified products with fatty acid metal salts; quaternary ammonium salts such as tributylbenzylammonium-1-hydroxy-4-naphthosulfonate and tetrabutylammonium tetrafluoroborate. , and analogues thereof such as phosphonium salts and lake pigments thereof; triphenylmethane dyes and lake pigments thereof; tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.); metal salts of higher fatty acids; diorganotin oxides such as dibutyltin oxide, dioctyltin oxide and dicyclohexyltin oxide; dibutyltin borate, dioctyltin borate , diorganotin borates such as dicyclohexyltin borate; guanidine compounds; imidazole compounds; imidazolium salts; A quaternary ammonium base-containing copolymer obtained by a technique such as quaternization with paratoluenesulfonic acid alkyl ester after polymerization is mentioned.

Effective negative charge control agents include, for example, organometallic complexes and chelate compounds, including monoazo metal complexes, acetylacetone metal complexes, aromatic hydroxycarboxylic acid metal complexes, aromatic dicarboxylic acid metal complexes, aromatic hydroxycarboxylic acid metal complexes, and aromatic hydroxycarboxylic acid metal complexes. There are acids, aromatic monocarboxylic acids, aromatic polycarboxylic acids, their metal salts, anhydrides, esters, bisphenol derivatives such as bisphenol, and coordination center metals are Sc, Ti, V, Cr, Co, Azo metal compounds selected from Ni, Mn, and Fe, and having cations selected from hydrogen ions, sodium ions, potassium ions, and ammonium ions, and coordination center metals of Cr, Co, Ni, Mn, Fe, and Ti , Zr, Zn, Si, B, and Al, and the cation is selected from hydrogen ion, sodium ion, potassium ion, ammonium ion, and aliphatic ammonium. metal compounds (aromatic hydroxycarboxylic acid derivatives and aromatic polycarboxylic acids are substituted with alkyl groups, aryl groups, cycloalkyl groups, alkenyl groups, alkoxy groups, aryloxy groups, hydroxyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups , acyl group, acyloxy group, carboxyl group, halogen, nitro group, cyano group, amide group, amino group, carbamoyl group), sulfonic acid group-containing acrylamide-based monomer and styrene-based monomer and a polymer containing a sulfonic acid group-containing monomer as a constituent component, such as a copolymer of (meth)acrylic monomers. These charge control agents may be used alone or in combination of two or more.
For color toners, colorless, white or light-colored charge control agents that do not affect the color tone and translucency of toner images are preferred.
Examples of negative charge control agents include salicylic acid derivative metals, calixarene compounds, organic boron compounds, and fluorine-containing quaternary ammonium salt compounds.
Positive charge control agents include, for example, resins having quaternary ammonium salts, carboxylates, or carboxyl groups as functional groups.

The content of the charge control agent in the toner is preferably 0.05 to 10 parts by weight, more preferably 0 parts by weight with respect to 100 parts by weight in total of the binder resin and the base resin, from the balance between the charge amount and the fluidity of the toner. .1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass. Moreover, as the method of addition, a method of adding to the inside of the toner, a method of adding to the outside, or a combination thereof can be applied.

In the toner according to the exemplary embodiment, it is preferable to add a surface treatment agent to the surface of the toner so that the surface treatment agent exists between the toner and the carrier or between the toners. By adding a surface treatment agent, powder flowability, storage stability, charge stability, and environmental stability can be improved, and the life of the developer can also be improved.

Conventionally known agents can be used as the surface treatment agent. Examples thereof include fine silica powder, fine titanium oxide powder, and hydrophobized products thereof. As silica fine powder, wet silica, dry silica, composite of dry silica and metal oxide, etc. can be used, and those obtained by subjecting these to hydrophobizing treatment with an organic silicon compound or the like can also be used. Hydrophobic treatment includes, for example, a method of treating silica fine powder produced by vapor phase oxidation of a silicon halogen compound with a silane compound and then treating with an organic silicon compound. Examples of silane compounds used for hydrophobizing treatment include hexamethyldisilazane, trimethylsilane, trimethylchlorosilane, trimethylethoxysilane, dimethyldichlorosilane, methyltrichlorosilane, allyldimethylchlorosilane, allylphenyldichlorosilane, benzyl Dimethylchlorosilane, Bromomethyldimethylchlorosilane, α-Chlorethyltrichlorosilane, β-Chlorethyltrichlorosilane, Chlormethyldimethylchlorosilane, Triorganosilylmercaptan, Trimethylsilylmercaptan, Triorganosilylacrylate, Vinyldimethylacetoxysilane, Dimethyldichlorosilane ethoxysilane, dimethyldimethoxysilane, diphenyldiethoxysilane, hexamethyldisiloxane, 1,3-divinyltetramethyldisiloxane, 1,3-diphenyltetramethyldisiloxane and the like. Examples of organosilicon compounds used for hydrophobic treatment include silicone oils such as dimethylsilicone oil, methylphenylsilicone oil, α-methylstyrene-modified silicone oil, chlorophenylsilicone oil, and fluorine-modified silicone oil. In addition, titanium oxide fine powder treated with oil, or vinyl resin fine particles having a size of 0.03 μm to 1 μm may also be used.

Other surface treatment agents include lubricants such as polyethylene fluoride, zinc stearate and polyvinylidene fluoride, cerium oxide, silicon carbide, strontium titanate, magnetic powder, abrasives such as alumina, carbon black, zinc oxide, and oxides. Conductivity-imparting agents such as antimony and tin oxide may also be used. Furthermore, as the shape of the surface treatment agent, there are various shapes such as small particles with a particle size of 100 nm or less, large particles with a particle size of 100 nm or more, octahedral, hexahedral, needle, and fibrous. may be used. Surface treatment agents may be used alone or in combination of two or more.

The amount of the surface treatment agent to be added is preferably 0.1 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, per 100 parts by weight of the toner.

When the toner according to the exemplary embodiment is used as a two-component developer, conventionally known carriers can be used. For example, particles having a number average particle size of 15 to 300 μm made of surface-oxidized or unoxidized metals such as iron, cobalt, manganese, chromium, copper, zinc, nickel, magnesium, lithium, rare earths, and alloys or oxides thereof. Available. These carriers may be surface-coated with a styrene resin, an acrylic resin, a silicone resin, a polyester resin, a fluorine resin, or the like. Furthermore, a magnetic carrier having a magnetic fine particle-dispersed core in which magnetic fine particles are dispersed in a resin and a coating layer containing a coating resin that coats the surface of the magnetic fine particle-dispersed core may be used.

The toner according to the exemplary embodiment can be used in various known developing processes. Examples include, but are not limited to, a cascade development method, a magnetic brush method, a powder cloud method, a touchdown development method, a so-called microtoning method using a magnetic toner produced by a pulverization method as a carrier, and triboelectrification between magnetic toners. A so-called bipolar magnetic toner method for obtaining a uniform toner charge is exemplified. Further, the toner according to the present embodiment can also be used in various conventionally known cleaning methods such as a fur brush method and a blade method. Further, the toner according to the exemplary embodiment can be used in various conventionally known fixing methods. Specific examples include an oilless heat roll method, an oil-applied heat roll method, a heat belt fixing method, a flash method, an oven method, a pressure fixing method, and the like. Further, it may be used in a fixing device employing an electromagnetic induction heating system. Furthermore, it may be used in an image forming method having an intermediate transfer step.

[Toner manufacturing method]
Next, a method for manufacturing the toner according to this embodiment will be described.
A method for manufacturing a toner according to the present embodiment includes a step of mixing the colorant masterbatch according to the present embodiment and a binder resin. In the step of mixing the colorant masterbatch and the binder resin, toner members other than the colorant masterbatch and the binder resin may be mixed.

The toner according to the exemplary embodiment is manufactured by mixing the colorant masterbatch according to the exemplary embodiment and a binder resin. The mixing method may be a conventionally known method. For example, a colorant masterbatch, a binder resin, and, if necessary, a toner component such as a charge control agent are sufficiently mixed with a powder mixer such as a Henschel mixer, and then mixed with a twin-screw kneader, an open roll kneader, or the like. The components are thoroughly mixed by melt-kneading using a kneader. After cooling, the particles are pulverized and classified to collect particles having a size of 4 to 15 μm, and the particles are sprinkled with a surface treatment agent by a powder mixing method to obtain a toner.
Further, the toner may be subjected to spheroidizing treatment by a surface treatment device or the like. Surface treatment methods include, for example, a method in which the toner is made spherical by flowing it into a high-temperature air jet, and a method in which corners of the toner are removed by mechanical impact. For the purpose of improving the image quality, these surface treatments may be performed to adjust the average circularity measured by a flow type particle image analyzer (eg FIPA-3000 manufactured by Sysmex Corporation) to 0.960 or more.
Further, in the method of making the toner spherical by flowing it into a high-temperature air jet, the particulate toner is heat-treated with hot air. The temperature at this time is preferably 200° C. or higher and 400° C. or lower.

The toner according to the exemplary embodiment can be suitably used as an electrophotographic toner for developing an electrostatic charge image in electrophotography, electrostatic recording, electrostatic printing, and the like.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than those described above can also be adopted.

EXAMPLES The present invention will be specifically described below with reference to Examples, but the present invention is not limited thereto. The data measurement and judgment methods are as follows. Furthermore, in the table, St represents styrene, Mac methacrylic acid, and BA n-butyl acrylate.

<Analysis of Resin>
(1) Viscoelasticity The storage modulus of the base resin at 110°C was measured under the following conditions.
Device: Viscoelasticity measuring device MCR302 (manufactured by Anton Paar)
Sample: 1g
Plate: φ20mm
Gap: 1mm
Swing angle γ: 1%
Frequency: 1Hz
Heating rate: 2° C./min With the temperature of the stage maintained at 150° C., the resin was placed on the stage and heated for 4 minutes, then sandwiched between plates, and excess resin protruding outside the plates was removed. Next, after the temperature of the stage was lowered to 50°C, the temperature was raised again and the storage elastic modulus at 110°C was measured.

(2) Weight average molecular weight Mw
The weight-average molecular weight Mw of the base resin is obtained by GPC (gel permeation chromatography) method, and is a converted molecular weight obtained by creating a calibration curve with monodisperse standard polystyrene. The measurement conditions are as follows.
GPC device: SHODEX (registered trademark) GPC SYSTEM-21 (manufactured by Showa Denko KK)
Detector: SHODEX (registered trademark) RI SE-31 (manufactured by Showa Denko K.K.)
Column: One SHODEX (registered trademark) GPC KF-G, three GPC KF-807L, and one GPC KF-800D (manufactured by Showa Denko Co., Ltd.) were connected in series in this order and used. .
Solvent: Tetrahydrofuran (THF)
Flow rate: 1.2 ml/min Sample concentration: 0.002 g-resin/ml-THF
Injection volume: 100 μL

(3) Glass transition temperature (Tg)
The glass transition temperature (Tg) of the base resin was measured using a differential scanning calorimeter (DSC-7000X, Hitachi High-Tech Science). Put 10 mg of the sample in an aluminum pan and melt it at 200 ° C. Then cool it to 0 ° C. and solidify it. Then, it was determined from the change in the amount of heat when the temperature was raised at 10° C./min.

<Evaluation of Masterbatch>
(1) Observation of Dispersion Aggregation of Colorant in Masterbatch Observation of dispersion aggregation of the colorant was performed by the following method. A thin film of the masterbatch prepared by sandwiching the colorant masterbatch between preparations using aluminum foil (thickness 12 μm) as a spacer and pressing at 150° C. and 3 MPa was observed with an optical microscope. The number of colorant aggregates was counted in a range of 0.5 mm×0.7 mm and evaluated according to the following evaluation criteria.
(Evaluation criteria)
○: 0 to 1 colorant aggregates of 10 μm or more were observed △: 2 to 5 colorant aggregates of 10 μm or more were observed ×: 6 or more colorant aggregates of 10 μm or more were observed observed

<Evaluation of Toner>
(1) Color Measurement The prepared cyan toner was placed in a color copier (IPSiO SP C820, manufactured by Ricoh Co., Ltd.), and a JBMIA color test chart for copiers was output with the cyan toner alone.
The color of the obtained image was measured with a fluorescence spectrodensitometer (FD-7, Konica Minolta), and from the obtained L*, a*, and b* values, IPSiO SP C820 genuine toner (polyester-based polymerized toner) was used. A color difference ΔE from the output image was calculated and evaluated according to the following evaluation criteria.

(Evaluation criteria)
○: ΔE is 2 or less △: ΔE is greater than 2 and 3.2 or less ×: ΔE is greater than 3.2

(2) Evaluation of Anti-Offset Property The prepared cyan toner was put into a copier modified from a commercially available electrophotographic copier, and an unfixed image with a toner adhesion amount of 0.45 mg/cm ² was produced. After that, the unfixed image is passed through a heat roller fixing device, which is a modified fixing unit of a commercially available copier, at a heat roller speed of 125 mm/sec. I observed no. The set temperature of the heat roller of the heat roller fixing device was repeatedly raised from 100° C. to 200° C. by 5° C., and the set temperature range within which toner staining did not occur was defined as the anti-offset temperature range. The atmosphere of the copying machine was set at a temperature of 22° C. and a relative humidity of 55%.
(Evaluation criteria)
○: 60°C < anti-offset temperature range △: 50°C ≤ anti-offset temperature range ≤ 60°C
×: Offset temperature range <50°C

[Production example of base resin for colorant masterbatch]
Resins A to I shown in Table 1 below were produced as base resins for colorant masterbatches.

Specific methods for producing Resins A to I will be described below.

(Resin A)
100 parts by mass of xylene was added to a nitrogen-purged flask, the temperature was raised, and 100 parts by mass of the monomers listed in Table 1 were mixed in advance with 10 parts by mass of t-butylperoxy-2-ethylhexanoate under reflux of xylene. The dissolved mixture was continuously added over 5 hours and refluxed for an additional hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain a resin A. Table 2 shows the physical properties of the obtained resin A.

(Resin B)
100 parts by mass of xylene was introduced into a nitrogen-purged flask and the temperature was raised, and 2.5 parts by mass of t-butyl peroxy-2-ethylhexanoate was added to 100 parts by mass of the monomers listed in Table 1 in advance under reflux of xylene. was added continuously over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain Resin B. Table 2 shows the physical properties of the obtained resin B.

(Resin C)
100 parts by mass of xylene was added to a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomers listed in Table 1 and 0.5 parts by mass of di-t-butyl peroxide were mixed and dissolved. The prepared mixture was continuously added over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 130° C., 0.5 parts by weight of di-t-butyl peroxide is added and reacted for 1 hour, and 0.5 parts by weight of di-t-butyl peroxide is added for 2 hours. A reaction was performed to obtain a polymerization liquid. The obtained polymerization liquid was flashed in a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain a resin C. Table 2 shows the physical properties of Resin C obtained.

(Resin D)
100 parts by mass of xylene was introduced into a nitrogen-purged flask, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomer described in Table 1 was added with 1.8 parts of t-butyl peroxy-2-ethylhexanoate. A mixed solution in which parts by mass were mixed and dissolved was continuously added over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain Resin D. Table 2 shows the physical properties of Resin D obtained.

(Resin E)
100 parts by mass of xylene was introduced into a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomer described in Table 1 was added with 2.5 parts of t-butyl peroxy-2-ethylhexanoate. A mixed solution in which parts by mass were mixed and dissolved was continuously added over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain a resin E. Table 2 shows the physical properties of Resin E obtained.

(Resin F)
100 parts by mass of xylene was added to a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomers listed in Table 1 and 10 parts by mass of t-butyl peroxy-2-ethylhexanoate were added. was added continuously over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain Resin F. Table 2 shows the physical properties of Resin F obtained.

(Resin G)
100 parts by mass of xylene was introduced into a nitrogen-purged flask, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomer described in Table 1 was added with 1.8 parts of t-butyl peroxy-2-ethylhexanoate. A mixed solution in which parts by mass were mixed and dissolved was continuously added over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The obtained polymerization liquid was flashed in a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain a resin G. Table 2 shows the physical properties of Resin G obtained.

(Resin H)
100 parts by mass of xylene was introduced into a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomers listed in Table 1 were mixed with 3 parts by mass of t-butyl peroxy-2-ethylhexanoate. was added continuously over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain Resin H. Table 2 shows the physical properties of Resin H obtained.

(Resin I)
100 parts by mass of xylene was introduced into a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 100 parts by mass of the monomer described in Table 1 was added with 2.5 parts of t-butyl peroxy-2-ethylhexanoate. A mixed solution in which parts by mass were mixed and dissolved was continuously added over 5 hours, and refluxed for 1 hour. Thereafter, the internal temperature is maintained at 98° C., 0.5 parts by weight of t-butylperoxy-2-ethylhexanoate is further added and reacted for 1 hour, and further t-butylperoxy-2-ethylhexanoate is added. 0.5 part by weight was added and reacted for 2 hours to obtain a polymerization liquid. The resulting polymerization liquid was flashed into a vessel (container) of 190° C. and 1.33 kPa to distill off the solvent and the like to obtain Resin I. Table 2 shows the physical properties of Resin I obtained.

[Production example of binder resin for toner]
100 parts by mass of xylene was charged in a flask purged with nitrogen, and the temperature was raised. Under reflux of xylene, 77.5 parts by mass of styrene monomer, 21.5 parts by mass of n-butyl acrylate, 1 part by mass of methacrylic acid, and t-butyl A mixed solution in which 1.8 parts by mass of peroxy-2-ethylhexanoate was mixed and dissolved was continuously added over 5 hours, and reflux was continued for 1 hour. After that, the internal temperature was maintained at 98° C., 0.5 parts by mass of t-butylperoxy-2-ethylhexanoate was added, the reaction was continued for 1 hour, and further t-butylperoxy-2-ethylhexanoate was added. 0.5 part by mass was added and the reaction was continued for 2 hours to obtain a low molecular weight polymer solution with a peak molecular weight of 21,000.
Next, 74 parts by mass of styrene monomer, 23.5 parts by mass of n-butyl acrylate, and 2.5 parts by mass of methacrylic acid were charged into a nitrogen-purged flask, and the internal temperature was raised to 120° C. and maintained at the same temperature. Polymerization was carried out for 8 hours. After adding 50 parts by weight of xylene and 0.2 parts by weight of tetraethylene glycol diacrylate, the temperature was raised to 110°C. 0.35 parts by weight of 1,1-bis(t-butylperoxy)cyclohexane and 60 parts by weight of xylene, which had been mixed and dissolved in advance, were continuously added over 9 hours while maintaining the temperature at 110° C., and the reaction was continued for 1 hour. Subsequently, 0.21 parts by mass of 1,1-bis(t-butylperoxy)cyclohexane was added, the reaction was continued for 2 hours, and 0.52 parts by mass of 1,1-bis(t-butylperoxy)cyclohexane was added. After addition, the reaction was continued for 2 hours to complete the polymerization to obtain a polymer solution having a peak molecular weight of 300,000.
These two solutions are mixed at a solid content mass ratio of low molecular weight polymer:high molecular weight polymer at a ratio of 8:2, and this is flushed into a vessel (container) of 190 ° C. and 1.33 kPa to distill off the solvent, etc. A toner binder resin having Mw of 110,000, Mw/Mn of 16 and Tg of 57° C. was obtained.

[Example 1]
(1) Production of colorant masterbatch A cyan pigment (ECB-303, Dainichiseika Kogyo), which is a colorant, and resin A, which is a base resin, are pressurized using steam as a heat source at the ratio shown in Table 3. It was put into a kneader and kneaded for 20 minutes.
After cooling the resulting kneaded product to 80°C, the kneaded product was taken out from the pressure kneader and passed through a three-roll mill (front roll temperature: 100°C, center roll temperature: 130°C, back roll temperature: 130°C) five times. Then, it was pulverized with a pulverizer to a size that could pass through a 3 mm punch net to prepare a colorant masterbatch. Regarding the obtained colorant masterbatch, the state of dispersion of the colorant was observed. Table 3 shows the results obtained.

(2) Production of toner Next, 18.75 parts by weight of the obtained colorant masterbatch and 6.25 parts by weight of wax (HNP-9, Nippon Seiro) were added to 100 parts by weight of the binder resin for toner. Mixed with a Henschel mixer. Next, the kneaded product prepared by kneading with a twin-screw extruder set at 90° C. was pulverized with a collision plate type jet pulverizer and classified with an air classifier to prepare colored particles having a median diameter of 8 μm.
To 100 parts by weight of these colored particles, 1 part by weight of silica (R976s, Nippon Aerosil), 0.2 parts by weight of titanium dioxide (ST550, Titan Kogyo), and 0.5 parts by weight of silica (X24-9600A-100, Shin-Etsu Chemical) A cyan toner of Example 1 was prepared by adding 1 part and mixing with a Henschel mixer. The obtained toner was subjected to color measurement and offset resistance evaluation. Table 3 shows the results obtained.

[Examples 2 to 6 and Comparative Examples 1 to 3]
A colorant masterbatch and a toner were prepared in the same manner as in Example 1, except that the type of the base resin used was the resin shown in Table 3, and the mixing ratio of the colorant and the base resin was changed to the ratio shown in Table 3. Each was produced and evaluated in the same manner as in Example 1. The obtained results are shown in Table 3, respectively.
Here, in Comparative Example 3, the kneaded material was fused inside the pulverizer in the process of pulverizing the kneaded material, and the toner of the target size (median diameter 8 μm) could not be produced.

[Example 7]
A colorant masterbatch was prepared in the same manner as in Example 1 except that the mixing ratio of the colorant and the base resin was changed to the ratio shown in Table 3, and the same evaluation as in Example 1 was performed. A toner was prepared in the same manner as in Example 1 except that the mixing amount of the colorant masterbatch was changed to 14.46 parts by weight and the mixing amount of the wax was changed to 6.02 parts by weight. made an evaluation.

[Example 8]
A colorant masterbatch was prepared in the same manner as in Example 1 except that the mixing ratio of the colorant and the base resin was changed to the ratio shown in Table 3, and the same evaluation as in Example 1 was performed. Further, a toner was prepared in the same manner as in Example 1 except that the mixing amount of the colorant masterbatch was changed to 9.92 parts by weight and the mixing amount of the wax was changed to 5.79 parts by weight. made an evaluation.

The hue of the printed image of the toner of the example was about the same as that of the genuine toner (polyester-based polymerized toner). On the other hand, the toners of Comparative Examples 1 and 2, in which the storage modulus of the base resin at 110° C. exceeded 10000 Pa, had poor dispersion of the pigment in the pigment masterbatch, and the hue of the printed image shifted. Further, in Comparative Example 3, the kneaded material was fused inside the pulverizer during the pulverization process, and the toner of the target size (median diameter of 8 μm) could not be produced.

Claims (7)

The base resin used in a toner colorant masterbatch containing a colorant and a base resin,
The base resin includes a vinyl resin,
The storage elastic modulus (G') at 110°C obtained by dynamic viscoelasticity measurement under conditions of a frequency of 1 Hz, a swing angle of γ1%, and a measurement temperature of 110°C is 10 Pa or more and 10,000 Pa or less,
The weight average molecular weight in terms of monodisperse standard polystyrene determined by gel permeation chromatography is 1,000 or more and 100,000 or less,
The vinyl resin contains at least one selected from polystyrene and styrene/(meth)acrylic copolymers,
The styrene-(meth)acrylic copolymer contains a styrene-based monomer, a (meth)acrylic-based monomer and a carboxyl group-containing monomer as constituent monomers,
In the styrene/(meth)acrylic copolymer, the content of the styrene-based monomer is 55% by mass or more and 99% by mass when the entire styrene/(meth)acrylic copolymer is 100% by mass. % or less, the content of the (meth)acrylic monomer is 0.5% by mass or more and 40% by mass or less, the content of the carboxyl group-containing monomer is 0% by mass or more and 15% by mass or less,
A base resin for a colorant masterbatch having a glass transition temperature (Tg) of 30° C. or higher and 80° C. or lower as measured by a differential scanning calorimeter (DSC). A colorant masterbatch comprising the base resin for a colorant masterbatch according to claim 1 and a colorant. In the colorant masterbatch according to claim 2 ,
The ratio (Y/X) of the content (Y) of the colorant to the content (X) of the base resin for the colorant masterbatch in the colorant masterbatch is 10/90 or more and 90/10 or less by mass. colorant masterbatch. A manufacturing method for manufacturing the colorant masterbatch according to claim 2 or 3 ,
A method for producing a colorant masterbatch, comprising the step of kneading a mixture of the colorant masterbatch base resin and the colorant at a temperature of 80° C. or higher and 150° C. or lower. A toner comprising the colorant masterbatch according to claim 2 or 3 and a binder resin. 6. The toner according to claim 5 ,
A toner in which the binder resin contains a styrene/(meth)acrylic copolymer. 7. The toner according to claim 5 , which is for electrophotography.