JPH03251852A - Toner and its production - Google Patents

Abstract

PURPOSE:To obtain the toner with the viscosity of the molten toner not significantly changed when fixed by using globular particles having a specified range of median diameter and a specified mol.wt. distribution, with the peak position of mol.wt. specified and obtained by the suspension polymerization. CONSTITUTION:The globular particles having 3-20mum median diameter as the volume basis and plural peaks in the mol.wt. distribution, with the peak position of the minimum mol.wt. controlled to <=50,000 and that of the maximum mol.wt. to >=200,000 and obtained by the suspension polymerization are used for the toner. As a result, the viscosity of the molten toner is not significantly changed when fixed, and an excellent toner is obtained with the fixability, offset resistance and adaptability to the device improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a toner in the field of electrophotography, and more specifically to a toner and a toner with excellent fixing properties and anti-offset properties during development. It relates to its manufacturing method.

(Prior Art) Toners used in the field of electrophotography are particles consisting of a fixing resin, a colorant, and optionally a charge control agent and a magnetic material. Toners are usually required to have development properties, fixability to transfer paper, and offset resistance.

Conventionally, in order to improve the fixing properties and anti-offset properties of toner, fixing resins have been made to contain low molecular weight hydrogenated polybutadiene (Japanese Unexamined Patent Publication No. 103354/1982) or reactive prepolymers (Japanese Patent Application Laid-Open No. 103354/1983). Kaisho 56-1109
48), and the ratio of styrene and 2-ethylmethahexyl methacrylate as a binder resin is used within a certain range (Japanese Patent Application Laid-open No. 6057855). In addition, a method for manufacturing toner particles has been proposed in which polymerization initiators with different half-lives are used in suspension polymerization, and the range of the ratio of the half-lives of the polymerization initiators is determined.
4-11941), the toner thus obtained has excellent anti-offset properties and anti-proking properties.

(Problem M to be solved by the invention) However, in order to improve fixing properties as in the past, simply adding (or existing) a low molecular weight resin to toner particles is not sufficient to improve fixing properties. I can't say it,
Further, in some cases, a problem may arise in offset resistance during fixing.

Furthermore, the durability of the toner itself is problematic, and compounding agents such as colorants that fall off from toner particles during printing may deteriorate development characteristics. This also applies when the ratio of binder resins is specified.

Also, the fixing roller is kept at a constant temperature during development, but
The state in which toner particles are heated is not necessarily constant. If the heating conditions of the fixing roller change slightly during development, the fixing resin in the toner changes in viscosity, changing its permeability and cohesiveness. For this reason, the fixing properties and anti-offset properties of the toner may be reduced and hot offset or cold offset may occur, and there is still room for improvement in toners in this situation.

Therefore, in view of these circumstances, the object of the present invention is to provide a fixing resin with a low-molecular component sufficient for fixing properties and a high-molecular component that imparts anti-offset properties and anti-blocking properties in an optimal state, and An object of the present invention is to provide a toner having a large particle size and mechanical strength, and a method for producing the same.

Another object of the present invention is to provide a toner that does not show much change in viscosity when the toner is melted during fixing, and thereby has excellent fixing properties, anti-offset properties, and device compatibility, and a method for producing the same. Our goal is to provide the following.

(Means for Solving the Problems) According to the present invention, a toner comprising a fixing resin and a colorant has a volume-based median diameter in the range of 3 to 20 ILm, and has a molecular weight distribution with multiple peaks. However, there is provided a toner characterized in that the minimum molecular weight peak position is 50,000 or less, the maximum molecular weight peak position is 200,000 or more, and the particles are spherical particles obtained by suspension polymerization.

The present invention is characterized in that the proportion of the high molecular weight component having a peak value of the maximum molecular weight or more is in the range of 10 to 40% of the total, and the particles are composed of spherical particles obtained by S turbidity polymerization. .

The present invention can also be characterized in that the suspension polymerized particles contain a releasing substance.

According to the present invention, in addition to the requirements for the toner particles, the viscosity of the toner is such that in the temperature range of 100 to 150° C. where the toner is heated during fixing, the viscosity of the toner increases by heating to sx 10'. 5x10' from poise
A toner is provided in which the temperature difference required to change to poise is 32° C. or more.

According to the present invention, in the toner fixing resin, when the glass transition temperature of the fixing resin is Tg, the toner outflow starting temperature is Ti, and the toner outflow temperature is Tm, the toner starts outflowing. Temperature Ti is Ti
- satisfies the range of Tz≦50 and 1/2 outflow temperature Tm
A toner is provided that satisfies the range of 30 above Tm-Ti.

According to the present invention, the average viscosity gradient (absolute value) of the toner in the temperature range of 100 to 150°C satisfies the range of 0.02 to 0.07/°C, and the absolute value of the viscosity gradient in the temperature range Provided is a toner characterized in that it has at least one region where 0.03 or less.

In the present invention, there are three regions in which the viscosity gradient is 0.03/°C or less, and the regions are in a temperature range of IF to 125°C;
The temperature may be in the range of 130 to 140°C.

The present invention may also be characterized in that the toner has a region where the viscosity gradient is slower than the average viscosity gradient of the toner in the temperature range by 10% or more.

According to the present invention, a toner is produced by suspension polymerization using a vinyl monomer and a colorant. In the method of polymerizing the vinyl heavy material, an initiator and a crosslinking agent having a half-life of 30 minutes or less are contained, and the polymer is polymerized so that the molecular weight distribution has multiple peaks. Provided is a method for producing a toner characterized by using the method.

The present invention is characterized in that when polymerizing the vinyl heavy body, a releasing substance is contained in addition to an initiator and a crosslinking agent, or when polymerizing the vinyl itite body, two or more substances having different half-lives are used. It is characterized by using a polymer containing the above initiator and crosslinking agent, at least one initiator having a half-life of 20 minutes or less, and polymerized so that the molecular weight distribution has a plurality of peaks. can do.

The present invention also provides 1
It can be characterized in that at least one of a colorant, a charge control agent, and a magnetic material is contained and polymerized.

The present invention may further be characterized in that polymerization is carried out such that among the plurality of peaks in the molecular weight distribution, the minimum peak molecular weight is 50,000 or less and the maximum peak molecular weight is 200,000 or more.

Note that the viscosity gradient of the toner indicates the ratio of the logarithm of the viscosity to the temperature. For this reason, the temperature difference (X
The amount of change in viscosity relative to +Δ)-x℃ is 11 (Y+△)
pois -1ogY pois, the viscosity gradient has the formula % formula %) = (log (Y + △) / Yl / Δ℃.K has a relationship with iNMx as the temperature increases, and the viscosity The measurement of viscosity is determined by a flow tester.

(Function) The present invention uses a polymerization N initiator and a crosslinking agent with a short half-life in suspension polymerization, thereby forming a fixing resin in which low molecular weight components and high molecular weight components can be clearly distinguished. This is based on the knowledge that when these components are present in a state in which blocking does not easily occur, and when made into a toner, its fixing properties and offset resistance are extremely excellent.

The toner of the present invention is composed of spherical toner particles obtained by suspension polymerization, and it is important that the toner particles have a volume-based median diameter in the range of 3 to 20 μm and a molecular weight distribution with multiple peaks. be. The median diameter of toner particles is adjusted during suspension polymerization, and multiple peaks in the molecular weight distribution are achieved by using an initiator or crosslinking agent with a short half-life during suspension. The toner of the present invention basically has a median diameter in the range of 3 to 20 um, particularly 5 um.
The toner particles range in size from 13 .mu.m to 13 .mu.m, and a toner particle group selected within this range becomes an excellent toner, and causes no toner scattering or fogging during development. Further, such a particle group has a nearly perfect spherical shape and the toner has good fluidity.

Also, in the case of multiple peaks in the molecular weight distribution.

The value of the minimum peak molecule in the particle is less than or equal to :)0000,
Preferably 3000 to 50000, particularly preferably 5
000 to 40,000, and the molecular weight value of the maximum peak is 200,000 or more, preferably 2,000oO to 70oOOOO1 special preference L< is 300,000 to 50
It is important to fill in the box of 00000. When low molecular weight components and high molecular weight components exist in toner particles with such a molecular weight distribution, when the toner is heated by a fixing roller etc., one low molecular weight component melts and sufficiently penetrates into the transfer agent, etc. and improves toner fixation. Further, the polymer component is mixed with the low molecule in a suitable state during suspension polymerization, so that blocking or the like does not occur and a certain degree of cohesiveness is exhibited throughout the fixing resin to prevent offset properties.

Further, in the present invention, it is preferable that the proportion of the high molecular weight component having a peak value of the maximum molecular weight or more is in the range of 10 to 40% of the total weight. High molecular weight ingredients or 1il in toner! When present within a range, the viscosity and cohesiveness of the toner particles as a whole are maintained sufficiently to provide sufficient release properties.

In the present invention, in addition to the fixing resin having a molecular weight distribution within the above-mentioned range, the viscosity of the toner decreases to 5xlO' due to heating in the temperature range of 100 to 130°C where the toner is heated during fixing. 5×10'p from ρoise
The temperature difference required to change to oise is 32℃ or more,
In particular, it is important to keep the temperature at 35°C or higher. A toner with such viscosity characteristics has less change in viscosity with respect to temperature than conventional toner particles, as shown in FIG.

For example, with conventional toner, the temperature changes from 5X10 poise to 5X lo'poise, but the temperature is 3Q.
A temperature increase of aC or less is sufficient. The fact that the viscosity gradient of the toner is slow in the above temperature range means that the viscosity of the toner remains constant to some extent even if the heating conditions during fixing vary slightly or the melting state of the toner varies. It is understood that In this way, in a state where there is no viscosity change, hot offset, cold offset, etc. can be totally prevented.

In the present invention, the average viscosity gradient of the toner is 0.02 to 0.0 in the temperature range of 100 to 150°C.
7/'C, and the viscosity gradient (absolute 4f) of the toner is 0.030/°C or less, particularly preferably 0.
It is important that at least one region exists where the temperature is below 0.026/°C. When a region where the toner has a low viscosity gradient exists, the fixing properties and offset resistance of the toner are sufficiently improved during fixing.

Furthermore, regarding the viscosity characteristics of such a toner, it is important that at the temperature v, @, there exists a region that is slower than the average viscosity gradient (absolute value) of the toner by 10%, particularly preferably by 15%. When the toner has a sufficiently slow viscosity gradient region, the toner can have better fixing properties and anti-offset properties during fixing.

FIG. 1 is a characteristic diagram showing the relationship between temperature and viscosity of the toner according to the present invention. As shown in FIG. 1, the viscosity change curve A of the toner of the present invention requires 40° C. to change from 5×10^ to 5×106. On the other hand, the viscosity gradient of the conventional toner curve B is considerably slower than 30° C. even though the temperature changes from 3×10 6 poise to 3× 10 4 poise.

In the present invention, as shown in FIG. 1, it is preferable that there be two regions where the viscosity gradient is 0.030 ρoise/°C or less. For example, if the first area is 115 to 12
Exists in a temperature range of 5℃, other regions are 130 to 140℃
It can exist in a temperature range of °C. A toner having such viscosity characteristics has good permeability into the transfer paper, has good cohesiveness when the fixing roller is separated, increases fixing properties, and the fixed toner does not easily separate from the transfer paper. Further, no dirt was observed on the fixing roller, and no offset was observed.

Furthermore, in the toner having such viscosity characteristics, the toner outflow start temperature Ti, the toner outflow temperature TI
When N is the glass transition temperature Tg of the fixing resin, Ti-T
It is preferable to use a toner of 30 on T-low Ti with g≦50. Normally, when trying to reduce the difference in Ti-Tg, the difference in TIII-T also tends to become smaller to 100 or less (Table 4 described later).6 However, in the toner particles of the present invention, the Togane state and the resin etc., and select T1
can be set within the above range, particularly Ti-Tg≦45, so that Tn-Ti is 35. When Ti is within the above range, the toner particles have a small difference in Ti-Tg and are easily dissolved, and can easily penetrate into the transfer paper side.
Since the difference between the toner and the toner is large, a mixed state of melted and non-melted substances exists for a long time, and the viscosity of the toner is maintained at a certain level.

Therefore, offset to the fixing roller etc. is prevented, and the anchor effect on the transfer paper is also maintained.

(Preferred embodiment of the present invention) In suspension polymerization, the present invention uses a polymerization initiator with a half-life of 30 minutes or less and a crosslinking agent, or uses a plurality of polymerization initiators with at least one initiator having a half-life of 20 minutes. The fixing resin has a low molecular weight component and a high molecular weight component present in a state where blocking is difficult to occur, and the toner particles have fixing properties and anti-offset properties. Further, the present invention allows the fixing resin to contain a release agent, even when there is a risk of containing a relatively large amount of low molecular weight components in the toner particles.
It is possible to provide a toner that can prevent staining of a roller surface used in a fixing means.

When vinyl monomers are subjected to suspension polymerization in the presence of a polymerization initiator with a half-life of 30 minutes or less, particularly 15 minutes or less, the initial stage of polymerization
As most of the initiator is deactivated, the degree of polymerization is stopped at a low level and a low molecular weight polymer is obtained. On the other hand, some of the polymerization reactants are made to have a high molecular weight by the crosslinking agent at the same time as the above reaction, and some active initiators remain even after the rapid reaction, or in the case of using multiple types of initiators. The polymerization reaction proceeds with the aid of another initiator. The high molecular weight polymer obtained here is mixed with the low molecular weight polymer obtained by the above reaction so as not to cause blocking to form the entire polymer. Addition of a crosslinking agent and a polymerization initiator with a short half-life can set conditions for forming multiple peaks of high molecular weight peaks and low molecular weight peaks in the molecular weight distribution of the entire polymer. It is possible to ensure the presence of low molecular weight polymers (FIGS. 2 to 4).

In addition, in order to obtain a toner polymer having these peak values, 0.00 parts by weight is added to 100 parts by weight of the crosslinking vinyl monomer. It is important to contain 3 to 10 parts by weight, especially 0.5 to 8 parts by weight. If the amount of the crosslinking agent increases beyond this range, the fixing properties of the toner particles will decrease, and if ψ is missing, the offset resistance and blocking resistance will decrease.

Further, the toner viscosity characteristics according to the present invention can be achieved by selecting the fixing resin component while satisfying the molecular weight distribution of the fixing resin during the suspension polymerization. The details will be shown below.

In the description of the present invention, it is roughly divided into raw materials used and suspension polymerization. The first explanation will be given below.

In the polymerization method of the present invention, in particular, those having ethylenically unsaturated bonds are used alone or in combination of two or more.

Suitable examples of such monomers include monovinyl aromatic monomers, acrylic monomers, vinyl ester m-mers,
These include heavy vinyl ethers, diolefin monomers, monoolefin monomers, and the like.

As a monovinyl aromatic 1lffi form, in the formula, R1 is a hydrogen atom, a lower alkyl group, or a halogen atom, and R
2 is a hydrogen atom, a lower alkyl group, a halogen atom, an alkoxy group, an amino group, a nitro group, a vinyl group, or a carboxyl group.

monohinyl aromatic hydrocarbons such as styrene, α-methylstyrene, vinyltoluene, α-chlorostyrene,
O-1m-, P-chlorostyrene, p-ethylstyrene, sodium styrene sulfonate, dihinylbenzene alone or in combination of 2'#i or more, and other monomers mentioned above include the following: are mentioned respectively.

CH? = C-Co-0-RA
...(2) In the formula, R7 is a hydrogen atom or a lower alkyl group, and R2 is a hydrogen atom, a hydrocarbon group having up to 12 carbon atoms, a hydroxyalkyl group, a vinyl ester group, or an aminoalkyl group. For example, acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, phenyl acrylate, methyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, Ethyl 3-hydroxyacrylate, γ-
and propyl hydroxyacrylate, δ-butyl hydroxyacrylate, β-hydroxyethyl methacrylate, γ-
Propyl aminoacrylate, γ-propyl acrylate, 1-diethylaminopropyl acrylate, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, etc.

Vinyl esters of formula % formula % (3) where R5 is a hydrogen atom or a lower alkyl group, such as vinyl formate, vinyl acetate, vinyl propionate, etc.

formula, CH2=CH R,R.

CH2=C-C=CH-Ro...(
5) In the formula, each of R-, R-, and R5 is a hydrogen atom, a lower alkyl group, or a halogen atom.

diolefins, especially butadiene, isoprene, chlorobrene, etc.

formula, R.

0-R1...(4) where R1 is a monovalent hydrocarbon group having up to 12 carbon atoms, vinyl esters such as vinyl methyl ether, vinyl ethyl ether, vinyl-n-butyl ether, vinyl phenyl ether, vinyl cyclohexyl ether, etc.

C8,=C-R,...(6) In the formula, each of R,..., H is a hydrogen atom or a lower alkyl group. Monoolefins, especially ethylene, propylene, isobutylene, butene-1, Pentene-1,4-methylpentene-1, etc.

(b) Polymerization initiator A polymerization initiator is used in the bulk polymerization and suspension polymerization of the present invention, and specific polymerization initiators include 2.2-azobis(2,4-dimethylvaleronitrile), 2. 2'-
Azobisisobutyronitrile, 1,1'-azobis(cyclohexane-1-carbonitrile), 2,2'-azobis-4-methoxy-2,4-dimethylvaleronitrile, 2,2-azobis(2-cyclo azo compounds such as propylprobionitrile), cumene hydroperoxide,
Radical polymerizable initiators such as peroxides such as t-butyl hydroperoxide, dicumyl peroxide, di-t-butyl peroxide, benzoyl peroxide, and lauroyl peroxide are used. In addition, combinations with ionizing radiation such as γ-rays and accelerated electron beams, and various sensitizers are also used.

The amount of polymerization initiators such as azo compounds and peroxides may be an appropriate amount of the new catalyst, and is generally prepared! It is preferable to use 0.1 to 10% by weight per child.

At least one type of polymerization initiator having a half-life of 20 minutes or less is used in suspension polymerization.

The half-life of 20 minutes or less means the value under the reaction temperature conditions during suspension polymerization, and if it is combined with a polymerization accelerator, the half-life under the influence of that accelerator. It means something.

(c) Crosslinking agent: A crosslinking agent is added during suspension polymerization to promote polymerization of vinyl monomers and bulk polymers.

Examples of crosslinking agents include divinyl compounds such as dihinylbenzene, divinyl ether, and divinyl sulfone, diallyl compounds such as allyl phthalate and diallylcarbinol, diacrylic esters such as diacrylphenol, ethylene glycol dimethacrylate, and trimethylolpropane. Any known per se such as triacrylate, glycidyl methacrylate, glycidyl acrylate, etc. can be used, but diacrylic esters are particularly preferred.

(d) Other compounding agents used in the polymerization step: In the present invention, polymerization accelerators, crosslinking agents, or chain transfer agents may be used as necessary, and these may be known per se, and are added in appropriate amounts. be able to.

Furthermore, in the polymerization step of the present invention, surfactants and dispersants known per se may be added in order to perform granulation and the like well.

(e) Coloring agent: Known dyes and pigments are used as the coloring agent, and specific examples are shown below.

a, black pigment carbon black, acetylene black, lamp black, aniline blank.

b, yellow pigments yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral first yellow, nickel titanium yellow, navels yellow, teftol yellow S, Hansa yellow 10G, benzidine yellow G, quinoline yellow lake, permanent yellow NGO, Tartrazine rake.

C2 orange pigment red yellow lead, molybdenum orange, permanent orange GTR, bilanron orange, halcan orange,
Indanthrene Brilliant Orange RK, Benzidine Orange G, Indanthrene Brilliant Orange GR
.

d, red pigment Venkara, cadmium red, red lead, mercury cadmium sulfide, Pernent Orange 4R, Lysole Red, Virazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B , Alizarin Lake, Brilliant Carmine 3B.

e, purple pigment mankan purple, fast violet B, methyl violet lake.

f, blue pigments navy blue, cobalt blue, alkali blue lake, Victoria blue lake, phthalocyanine blue thermometallic phthalocyan blue, phthalocyanine blue partially chlorinated product, fast sky blue, indansen blue BC.

g, I & color raw materials chrome green, chromium oxide, pigment green B,
Malachite Green Lake 2 Fanal Yellow Green G.

h, white powder Zinc white, titanium oxide, antimony white, zinc sulfide.

i2 extender pigments Palite powder, barium carbonate, clay, silica, white carbon, talc, aluminum white.

These coloring agents can be added in an amount of 1 to 20 parts by weight, particularly preferably 5 to 15 parts by weight, per 1001 parts of the polymerizable monomer.

In order to prevent offset from toner, we use low molecular weight polyethylene, low molecular weight polypropylene, various waxes,
A mold release agent such as silicone oil can be included. These mold release agents contain 0.1 parts per 100 parts of the polymerizable at-form.
1 part to 10 parts, particularly preferably 0. It is preferable to use 5 to 8 parts.

(f) Other ingredients contained in the toner Magnetic materials Pigments include, for example, tritetraoxide (Fe, OA).

Iron sesquioxide (7-Fe?0.), iron zinc oxide (ZnFe
? 0. ), iron yttrium oxide (Y, Fe, 0..2)
, cadmium oxide (Gd=Fe-0, p), iron copper 11ide (CuFe?0.), iron lead oxide (PbFe, 201.)
, neodymium iron oxide (NbFeO,), barium iron oxide (BaFe, □04.), magnesium iron oxide (MgF
e20a), iron mankane oxide (MnFe20.), lanthanum iron oxide (LaFeO,)-iron powder (Fe), cobalt powder (Co), nickel powder i), etc. are known.
In the present invention, any of these known fine powders of magnetic materials can be used.

In addition, in order to adjust the chargeability of the toner, a charge control agent known per se may be used, for example, a metal-containing 3zo dye, (3Rkyl)
Metal compounds of salicylic acid, metal soaps of naphthenic acid, fatty metal soaps, resin acid soaps, etc. can also be blended. These charge control agents contain 100 parts of polymerizable i-mer per part of 0
．． Parts of 1 to 10 parts, particularly preferably 0.5 to 5 parts, can be used. In order to provide an offset prevention effect to the toner, a release agent such as low molecular weight polyethylene, low molecular weight polypropylene, various waxes, silicone oil, etc. can be included. These mold release agents are polymerizable it form 1
0.1 to 10 parts by weight, particularly preferably 1 to 8 parts by weight, per 0.001 parts by weight. These compounding ingredients including polymerizable weights and colorants are sufficiently mixed and dispersed and then subjected to suspension polymerization.

11 In the imperial suspension polymerization, the dispersion medium is usually water-soluble,
Water, alcohol, etc. are used. The vinyl-based IT material is usually suspended in a dispersion medium in an amount of 100 to 2000 g per 1 liter of the dispersion medium, although it differs depending on the type. During suspension granulation, surfactants and dispersion stabilizers are used, and these are known per se, but especially fatty acid-based and sulfonic acid-based anionic surfactants are used as surfactants. It is desirable to use a sparingly soluble inorganic salt or the like as a dispersion stabilizer.

Granulation in a dispersion medium during suspension polymerization is carried out using a homomixer,
This is carried out using a high-speed shearing stirrer such as a homogenizer, and the granulation diameter is preferably in the range of 3 to 20 μm.

By setting the granulation diameter within the above range, toner particles of an appropriate size can be obtained.

During suspension polymerization, as described above, at least one type of initiator having a half-life of 30 minutes or less, particularly 20 minutes or less, and at the same time a slow polymerization initiator and a crosslinking agent are mixed. These blends are suitably carried out before or after granulation.

The reaction temperature is preferably 30 to 100°C, particularly 40 to 90°C. Further, in the present invention, it is desirable to change and lower the reaction temperature midway through the reaction. That is, 10 to 60 minutes after the short half-life polymerization initiator is deactivated,
It is desirable to lower the reaction temperature to a range of 5 to 30°C,
By lowering the reaction temperature in this manner, the remaining polymerization initiator undergoes a slow reaction, facilitating the formation of a high molecular weight polymer and a low molecular weight polymer. Note that the half-life of 30 minutes is the time at the above temperature in the suspension polymerization reaction system.

Furthermore, the polymer of the toner of the present invention contains a release agent, and I!
The molding agent may be added in the vinyl polymer or after polymerization, but it is preferably added in the it form. The type II agent is present in the toner and can prevent contamination of the fixing means, extend the life of the fixing means, and further increase the proportion of low molecular weight polymers.

Toner particles The obtained toner particles are composed of a low molecular weight polymer and a high molecular weight polymer, and both types of compounds have anti-blocking properties.
In addition, additives such as colorants are incorporated into the polymer chains.

Among the molecular weight peaks of toner particles, the minimum peak molecular weight value is 50,000 or less, preferably 3,000 to 500.
00, particularly preferably in the range of 5,000 to 40,000, and the maximum peak molecular weight value is 200,000 or more, preferably 200,000 to 7,000,000. Especially good *
L < C is in the range of 300,000 to 50oooooo, and it is clear that low molecular weight polymers and high molecular weight polymers are present in the toner. The position of the maximum peak is 200
When it is less than 000, offset resistance, bronking resistance,
It becomes difficult to impart sufficient abrasion resistance, and when the minimum peak position exceeds 50,000, it becomes difficult to impart fixing properties.

Furthermore, in addition to the position of the molecular weight peak, the maximum high molecular weight component, that is, the high molecular weight component having a molecular weight equal to or higher than the maximum molecular weight peak can be present in a range of 10 to 40% based on the total. Toner particles in this range have improved blocking resistance and durability, and exhibit stable performance over a long period of time. Furthermore, if the proportion of the maximum high molecular weight component falls outside of this range, long-term stability may not be achieved and stains may occur.
Roller stains may occur, and as the proportion of the maximum high molecular weight component increases, fixing performance tends to decrease.

In addition, the toner particles obtained by suspension polymerization are spherical, and the coloring agent, mold release agent, etc. are incorporated into the polymer chain, so that the toner particles do not come off and have excellent durability and fluidity. There is sex.

In addition to these structural characteristics of toner particles, particle size measurements using a flow tester show that in the temperature range of 100 to 130°C, where the toner is heated during fixing, the viscosity of the toner increases by 5X 10 due to heating. The temperature difference required to change from 'poise to 5x 10' poise is 32°C or more, particularly preferably 35°C or more. A toner that maintains such a temperature difference has little change in viscosity and is excellent in fixing properties, anti-offset properties, and device compatibility.

FIG. 1 is a characteristic diagram showing the relationship between temperature and viscosity of the toner according to the present invention. The horizontal axis is the temperature, and the vertical axis is the logarithm of the viscosity. As shown in FIG. 1, the viscosity change curve A of the toner of the present invention is 1. )X 10'poise to 3x
It takes 40°C to change to 10'poise, and the slope is much slower than that of the conventional toner curve B at 30°C. That is, if it is a conventional toner, 5X lo'po
To change from ISE to 5X lo'poise, the temperature only needs to be increased by 30°C or less, but with the toner of the present invention,
It is necessary to raise the temperature to at least 40°C.

In the present invention, when the viscosity change is expressed as the average viscosity gradient of the toner, the average viscosity gradient (absolute value) of the toner in the temperature range of 100 to 150°C is 0.02 to 0.07.
/°C is desirable. The viscosity of toner is because the fixing resin gradually melts as the temperature rises! 11
ts decrease, and its viscosity gradient takes a negative value. Viscosity gradient 1! ! The relative value affects the viscosity fluctuation of the toner, and if its absolute value is large, the viscosity change with respect to the temperature of the toner becomes large. In the present invention, the average viscosity gradient of the toner is 0.0 as shown in FIG.
It is in the range of 2 to 0.07/°C. As shown in Fig. 1, toner particles in this range are smaller than conventional toner particles.
It is easy to understand that there is no change in viscosity with respect to temperature, and that there is tolerance in setting the heating conditions of the fixing roller.

Furthermore, in the toner particles of the present invention, the viscosity gradient region that is slower than the average viscosity gradient in the above temperature range accounts for 10%, particularly 15% or more. Toner particles also. At least one region in which the toner viscosity gradient (absolute) is 0.037°C or less, particularly preferably 0.026/°C or less is made to exist.

During toner fixing, the toner is heated for a short period of time by a fixing roller at approximately 180°C. Due to this heating, the toner starts to melt at around 100°C, and when the toner is in an appropriate IgIIi state, the resin penetrates into the transfer paper, and when the fixing roller is separated, it exerts a certain cohesive force and anchor effect, and the toner melts on the transfer paper side. It is well established.

In this case, it is understood that some of the fixing resin components of the toner of the present invention exhibit different physical properties. A fixing resin component that lowers the viscosity of the toner acts, and a fixing resin component that does not change the viscosity characteristics of the toner as a whole acts so much as the temperature rises in a region where the viscosity gradient is slow, although the melting state changes.

As shown in FIG. 1, the viscosity change curve A of the toner of the present invention has a slope of -0,
014/°C, and the slope is -0,025/°C in the temperature range of 130°C to 140°C. On the other hand, the viscosity gradient of the conventional toner curve MB is 0.05/°C or higher at all temperatures in the range of 100 to 150°C. Therefore, when the toner particles of the present invention are heated by the fixing roller, the viscosity does not change and is maintained at a predetermined viscosity, or the viscosity gradient of the conventional toner is 0.03.
If the temperature exceeds /°C, the viscosity changes drastically, which affects permeability, cohesiveness, and anchoring effect, which are factors for fixing properties and anti-offset properties.

The present invention also provides the viscosity gradient of 0.0 as shown in FIG.
It is preferable that there are 211 regions of 3/'C or less. For example, a first region can exist in a temperature range of 115-125°C and another region can exist in a temperature range of 130-140°C. A toner having such viscosity characteristics has good permeability into the transfer paper, has good cohesiveness when the fixing roller is separated, improves fixing properties, and does not easily escape from the transfer paper. Further, no dirt was observed on the fixing roller, and no offset was observed.

(Effects of the Invention) According to the present invention, the molecular weight distribution is made to have a specific distribution degree, and the molecular weight distribution has a plurality of peaks, and the toner particles are made into spherical particles obtained by suspension polymerization. The toner formed from the toner particle group has excellent fixing properties, anti-blocking properties 2 and anti-offset properties. In addition, in the above-mentioned toner, the viscosity characteristics of the toner particles are made to be within a specific range in the range of 100 to 150 degrees Celsius once the toner is heated during fixing. It also improves offset resistance and improves toner compatibility with devices.

(Example) Examples are shown below. Note that the present invention is not limited to this.

(Example 1) Styrene 80 parts by weight 2-ethy7-hexyl methacrylate 20 parts by weight tS carbon blank, MA-1005 parts by weight (manufactured by Mitsubishi Chemical Corporation, trade name) Charge control agent, Bontron 5-40 1 part by weight ( Orient Chemical Co., Ltd., trade name) dihinylbenzene 1-polymer FF19B polymerization initiator, 2,2'-ambis (2,4-1 parts by weight) dimethylvaleronitrile (half-life at 80°C: approximately 10 minutes) A mixture of these with 400 parts by weight of water 6 parts of tricalcium phosphate and 0.01 parts of sodium dodecylbenzenesulfone were added to the continuous phase, granulated using a homomixer, heated to 80°C, and polymerized for 10 hours. Then, the obtained polymer was treated with dilute acid, washed with water, and dried to obtain toner particles.When the particle size characteristics were measured using a Coulter counter, the volume-based median diameter D5' was obtained.
had a sharp particle size distribution of 10.3 μm.

In addition, when the molecular weight distribution was measured by GPC, the first
As shown in the figure, it has two peaks, the overall weight average molecular type (M) is 340,000, the peak on the polymer side is at 1,200,000, and the peak on the low molecular weight side is 3.
It was located at 5,000.

Then, 0.1 part by weight of hydrophobic silica is mixed per 100 parts by weight of the obtained toner, and a carrier in which ferrite particles are coated with silicone su'i is mixed so that the toner concentration is 3%, and a developer is prepared. And so. And electrophotographic copying machine DC-1205 (manufactured by Sanda Kogyo Co., Ltd., trade name) [
A printing durability test of 10,000 sheets was conducted at a printing speed of 12 A4 sheets per minute, and the fixing properties and anti-offset properties were evaluated. Regarding fixing properties, a transfer paper with a toner image formed thereon is passed through and fixed, an adhesive tape is pressed against the formed fixed image, and then peeled off, and the fixed image is compared before and after peeling off. The density was determined by measurement using a reflective density needle (manufactured by Tokyo Juishiki), and was evaluated by calculating. In addition, offset resistance was evaluated based on whether an offset phenomenon occurred during continuous copying. At the same time, wear resistance was also evaluated by looking at the generation of fine particle components. Regarding blocking resistance, put 20g of toner into a glass cylinder with an inner diameter of 26.5mm in an oven at 60°C, and place 20g of toner on top of the toner.
A weight was placed on the cylinder and the cylinder was left to stand for 3 minutes, after which the cylinder was removed and the toner was evaluated to see if it crumbled.

The results are shown in Table-1.

(Example 2) Styrene 80! E-quantity n-butyl methacrylate 20 weight tS carbon blank, A-1005 parts by weight (manufactured by Mitsubishi Kasei Co., Ltd., trade name) Charge control agent, Bontron 5-40 1 part by weight (manufactured by Orient Chemical Co., Ltd., trade name) Divinyl Benzene 1.1 weight 1 m2-Ethylene coulicol methacrylate
1.5ffi mass% polymerization initiator, 2,2'-azobis(2-cyclopropylpropionitrile 7-tS(
A mixture with a half-life of 11 minutes at 75°C was placed in the same continuous phase as in Example 1 and granulated. Next, suspension polymerization was performed at 75° C. for 6 hours to obtain toner particles.

The particle size characteristics of the obtained toner are the volume-based median diameter D
” was 10.2 μm and had a sharp particle size distribution.

In addition, when the molecular weight distribution was measured by GPC, it was found that 1,6
It had peaks at the 00,000 and 30,000 positions, and the overall weight average molecular weight was 310,000.

A developer was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table-1.

(Example 3) Styrene 80 parts n-
Butyl methacrylate 20 parts carbon black, 1 part #-10005 (manufactured by Mitsubishi Kasei Co., Ltd., trade name) Charge control agent, 1 part Bontron 5-40 (manufactured by Orient Chemical Co., Ltd., trade name) Divinylbenzene 1. 2-ethylene chloride methacrylate
A mixture of 1.51ktifl1 polymerization initiator and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (half-life at 60°C of approximately 12 minutes) was charged into the same continuous phase as in Example 1. It was granulated. and,
A toner was obtained by suspending at 60° C. for 11 hours.

The particle size characteristics of the obtained toner are the volume-based median diameter D
” was 11.0 μm, and had a sharp particle size distribution.

In addition, when the molecular weight distribution was measured by GPC, 1,3
It had peaks at the 00,000 and 28,000 positions, and the overall weight average molecular weight was 430,000.

A developer was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table-1.

(Example 4) Styrene 80 parts by weight n-butyl methacrylate 20 parts by weight carbon black, MA-1005 parts by weight (manufactured by Mitsubishi Chemical Corporation, trade name) Charge control agent, Hontron 5-40 1 part by weight (Orient Chemical Co., Ltd.) (product name) divinylbenzene 1.8 parts 2-ethylene glycol dimethacrylate
A mixture of 1.5 parts polymerization initiator and 2,2'-azobis(2,4-dimethylvaleronitrile) (half-life at 80°C of about 10 minutes) was charged into the same continuous phase as in Example 1. Granulated. Then, suspension polymerization was carried out at 80° C. for 9 hours to obtain a toner.

The particle size characteristics of the obtained toner are the volume-based median diameter D
'Q was 9.5 μm, and it had a sharp particle size distribution.

In addition, when the molecular weight distribution was measured by GPC, 7,9
It had peaks at the 00,000 and 5,600 positions, and the overall weight average molecular weight was 2,300.000.

A developer was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table-1.

(Comparative Example 1) In Example 1, the polymerization temperature was set at 65°C [initiator 2.2'-
Azobis(2,4-dimethylvaleronitrile) at 65℃
The particle size characteristics of the toner obtained by carrying out suspension polymerization for 13 hours with a half-life of 1/100 are the volume-based median diameter D.
50 was 10.4 μm, and had a sharp particle size distribution.

In addition, when the molecular weight distribution was measured by GPC, it was found that 4.0
It has peaks at the 00,000 and 100,000 positions, and the overall weight average molecular weight is 1,000. It was OOO.

A developer was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table-1.

(Comparative Example 2) A toner was obtained by performing a polymerization reaction in the same manner as in Example 1 except that divinylbenzene as a crosslinking agent was not used.

The particle size characteristics of the obtained toner are the median diameter D based on 1 volume.
No. 50 had a diameter of 10.1 μm and a sharp particle size distribution.

In addition, when the molecular weight distribution was determined by GPC, only a single peak was observed, and the overall weight average molecular weight was 1,000.
It was 0,000.

A developer was prepared in the same manner as in Example 1, and a similar test was conducted. The results are shown in Table-1.

(Comparative Example 3) In Example 2, the polymerization temperature was set at 60°C (initiator 2,
A polymerization reaction was carried out in the same manner except that the half-life KA of 2'-azobis(2-cyclopropylprobionitrile) at 60°C was changed to 65 minutes.

The particle size characteristics of the obtained toner are the volume-based median diameter D
50 was 9.8 μm, and had a sharp particle size distribution.

In addition, when the molecular weight distribution was measured by GPC, it was found that 1,8
It had peaks at the 00,000 and 850,000 positions, and the overall weight average molecular weight was 1,100,000.

A developer was prepared in the same manner as in Example 1, and the same test was conducted. The results are shown in Table-1.

(Example 5) Styrene 5 oxt parts 2-ethylhexyl methacrylate 20 parts by weight Carbon black, MA-1o.

(manufactured by Mitsubishi Kasei Co., Ltd., trade name) 5 parts charge control agent, Bontron S-40 (manufactured by Orient Chemical Co., Ltd., trade name) 1 part divinylbenzene 1.8 parts by weight 2-ethylene glycol dimethacrylate 1.5 parts Parts by weight Low molecular weight polypropylene (Viscol 550 P.

(Product name manufactured by Mitsubishi Kasei Corporation) Double polymerization initiator, 2,2'-azobis(2,4-dimethylvaleronitrile (half-life at 80°C: approximately 10 minutes) 1
0 parts by weight These mixtures were added to a continuous phase containing 40 parts by weight of water, 6 parts by weight of tricalcium #l acid, and 0.01 parts by weight of sodium dodecylbenzenesulfonate, and granulated with a homomixer to give 80 parts by weight. The polymerization was carried out for 10 hours by raising the temperature to "C".The resulting polymer was treated with dilute acid, washed with water, and dried with 1tLi to obtain toner particles.

When the particle size characteristics were measured using a Coulter counter, the volume-based median diameter was 11.2 μm, and the particle size distribution was sharp.

In addition, when the molecular weight distribution was determined by GPC,
As shown in Figure 3, it has multiple peaks, the overall weight average molecule; t (Mw) is 1,900,000, and the maximum polymer side peak is at 6,100,000.
The peak of s on the low molecular side was located at 44,000. Then, 0.1 part by weight of hydrophobic silica was mixed per 100 parts by weight of the obtained toner, and the mixture was mixed with a carrier in which ferrite particles were coated with silicone resin so that the toner concentration was 3%, thereby forming a developer. . And an electrophotographic copying machine DC-1205 (manufactured by Sanda Kogyo Co., Ltd.).

A printing durability test of 20,000 sheets was conducted using the product (trade name), and the fixing properties and anti-offset properties were evaluated.

The results are shown in Table-2.

(Example 6) Styrene 80! ! Parts by weight n-butyl methacrylate 20 parts by weight Carbon black,
#-1000 (manufactured by Mitsubishi Kasei Corporation, trade name) 5 parts by weight charge control agent,
Bontron S-40 (manufactured by Orient Chemical Co., Ltd., trade name) 1st ffiffl + dihinylbenzene 1.3 parts by weight Low molecular weight polypropylene (Viscol 660p, made by Mitsubishi Kasei Co., Ltd., trade name) 2 parts by weight Polymerization initiator, 2,2'-azobis ( A mixture of 7 parts of 2,4-dimethylvaleronitrile (half-life at 80°C: approximately 10 minutes) was added to the same continuous phase as in Example 5 for granulation.Then, the mixture was suspended at 80°C for 10 hours. Polymerization was performed to obtain toner particles.

The obtained toner had a sharp particle size distribution with a volume-based median diameter of 5 m of 9.5 μm. In addition, the weight average molecular weight by GPC is 6400
00, the maximum peak was 2,100,000, and the minimum peak was 38,000.

Then, the developer was prepared in the same manner as in the example, and the same test was conducted. The results are shown in Table-2.

(Example 7) 75 parts by weight of styrene 25 parts by weight of 2-ethylhexyl methacrylate Carbon black, #-1000 (manufactured by Mitsubishi Chemical Corporation, trade name) 5 parts by weight Charge control agent,
Hontron S-40 (trade name, manufactured by Orient Chemical Co., Ltd.) 1 weight, 1 part divinylbenzene, 1 weight, 1 part, low molecular weight polypropylene (Viscol 550P, manufactured by Sanyo Chemical Co., Ltd., trade name)
Example 5 A mixture of 2 parts by weight of a polymerization initiator and 5 parts by weight of 2.2'-azobis(4-methoxy-2,4-dimethylvaleronitrile) (half-life at 80°C: about 1 minute)
The mixture was poured into a continuous phase similar to the above and granulated. Then, suspension polymerization was carried out at 80° C. for 10 hours to obtain a toner.

The particle size characteristics of the obtained toner are the median diameter on a volume basis. was 10.3 μm and had a sharp particle size distribution. In addition, the weight average molecular weight by GPC is 300
000, the maximum peak was 1,100,000, and the minimum peak was 28,000.

Then, prepare the developer in the same manner as in the example.

A similar test was conducted. The results are shown in Table-2.

(Comparative Example 4) In Example 5, the polymerization temperature was 65°C (initiator 2.2'
-Half-life of azobis(4-methoxy-2,4-dimethylvaleronitrile) at 65°C (100 minutes) is 11
Time suspension polymerization was performed to obtain a toner.

The particle size characteristics of the obtained toner are the volume-based median diameter D
%, was a serious offense of 11.0, and had a sharp particle size distribution. In addition, weight average molecular weight i, t4 by GPC
000000T', maximum peak is 12000000T,
The A small peak was 800,000.

Then, prepare the developer in the same manner as in the example, and use the same K.
I did m. M fruits are shown in Table-2.

(Example 8) Styrene 80i! Dobe 2-ethylhexyl methacrylate 20 East 1 part carbon black, MA-100 (manufactured by Mitsubishi Kasei Corporation, trade name) 5-fold lt part charge Ill
Dance agent, Bontron S-40 (manufactured by Orient Chemical Co., Ltd., trade name) 1 part by weight divinylbenzene 0. 7 parts 1 part 2-ethylene glycol dimethacrylate 1.5 parts by weight Polymerization initiator, [2,2'-azobis(4-methoxy 2
゜4-dimethylvaleronitrile) Half-life at 70°C: 3.5 minutes, half-life at 60°C: approximately 10 minutes] 4 parts by weight polymerization initiator, 2,2'-azobis(2,4-dimethylvaleronitrile, 70°C) Half-life at approximately 40 minutes at 60°C
half-life of about 180 minutes) 2 parts by weight of a mixture of these, 400 parts by weight of water, 6 tt parts of tricalcium #l acid and 0.0 parts of sodium dodecylbenzenesulfonate.
01 parts by weight was added to the continuous phase, granulated using a homomixer, polymerized for 3Q minutes at 70°C, and polymerized at 60°C for 8 hours. Then, the obtained polymer was treated with a dilute acid, washed with water, and dried to obtain toner particles. When particle size characteristics were measured using a Coulter counter, the volume-based median diameter was 1. had a sharp particle size distribution of 10.7 μm. In addition, when the molecular weight distribution was measured by GPC, there were multiple peaks as shown in Figure 4, and the overall weight average molecular weight (1t) was 410,000, with the largest peak on the polymer side at 2,300,000. can be,
The smallest peak on the low molecular side was at the position of 29,000.

In addition, high molecular weight components with a molecular weight higher than the maximum molecular weight peak (
The percentage of the whole (shaded area in the figure) is 15.6%
Met.

Then, 0.1 part by weight of hydrophobic silica was mixed per 100 parts by weight of the obtained toner, and the mixture was mixed with a carrier in which ferrite particles were coated with silicone resin so that the toner concentration was 3%, thereby forming a developer. . Then, 2
A printing durability test of 10,000 sheets was conducted to evaluate fixing properties and offset resistance.

The M results are shown in Table 3.

(Example 9) Styrene 7Q heavy duty 2-ethylhexyl methacrylate) 30 parts by weight carbon black, #-1000 (manufactured by Mitsubishi Chemical Corporation, trade name) 5 parts by weight charge control agent,
Bontron S-40 (manufactured by Orient Chemical Co., Ltd., trade name) 1% divinylbenzene 0. 9 parts by weight polymerization initiator, [2
,2-azobis(2,4-dimethylvaleronitrile)8
Half-life at 5°C: approximately 5 minutes, half-life at 75°C: 3 minutes
o) Quadruple one-part polymerization initiator, [2,2'-azobis(2-methylpropionitrile) (2,2-asobisbutyronitrile), half-life at 85°C approximately 50
minutes, half-life at 75°C approximately 200 minutes]
Two parts by weight of these mixtures were added to the same continuous phase as in the example and granulated. Next, suspension polymerization was performed at 85° C. for 40 minutes and at 75° C. for 8 hours to obtain toner particles.

The particle size characteristics of the obtained toner are the volume-based median diameter D
It had a sharp particle size distribution of %11 to 9.6 μm. In addition, the weight average molecular weight by GPC is 86
0000, maximum peak is 3200000, maximum tJ\
Beak was 15,000. Furthermore, the proportion of high molecular weight components having a molecular weight equal to or higher than that of the maximum molecular weight peak was 29%.

Then, a developer was prepared in the same manner as in the example, and the same test was conducted. The results are shown in Table-3.

(Example 10) Styrene 70 parts n-butyl methacrylate 30 parts carbon black, #-1000 (manufactured by Mitsubishi Kasei Corporation, trade name) 5 parts 1 part charge dissipating agent,
Bontron S-40 (Orient Kagakushaen, trade name) 1 part by weight divinylbenzene 1 part polymerization initiator, [2,2
'-azobis(2-methylpropionitrile) (2
, 2-azobisisobutyronitrile), half-life at 80°C approximately 100 minutes, half-life at 76°C approximately 200 minutes]
Two-fold one-part polymerization initiator, [2,2-azobis(2-cyclopropylpropionitrile)] Half-life at 80°C: approximately 6.5 minutes, half-life at 75°C: approximately 12
) 2 parts The mixture was added to the same continuous phase as in Example 8 and granulated. Then, at 80°C for 40 minutes, 75
Suspension polymerization was carried out at °C for 8 hours to obtain toner particles.

The obtained toner had a sharp particle size distribution with a volume-based median diameter of 10.4 μm. In addition, the weight average molecular weight by GPC is 950
000, the maximum peak was 3,800,000, and the lowest peak was 20,000. In addition, polymer j! with a molecular weight higher than the maximum molecular weight peak! [The proportion of all components was 32%.

Then, a developer was prepared in the same manner as in the example, and the same test was conducted. The results are shown in Table-3.

(Example 11) Styrene 70 parts by weight n-butyl methacrylate 30 parts by weight Carbon black, MA-100 (manufactured by Mitsubishi Kasei Co., Ltd., trade name) 5-part charge control agent, Bontron S-40 (manufactured by Orient Chemical Co., Ltd., Product name) 1 part by weight divinylbenzene 0.9 parts by weight 1 part by weight 2-ethylene glycol dimethacrylate 1.5 parts by weight Polymerization initiator, (2,2'-azobis(2-cyclopropionitrile) half-reduced at 80°C Period: 6.5 minutes] 2 parts by weight Polymerization initiator, 2,2''-azobis(2-methylbutyronitrile), half-life at 80°C: approximately 200] 2 parts by weight A mixture of these was added continuously in the same manner as in Example 8. The mixture was added to a phase and granulated. Next, suspension polymerization was carried out at 80° C. for 10 hours to obtain toner particles.

The particle size characteristics of the obtained toner are the volume-based median diameter D
5. was 9.4 μm and had a sharp particle size distribution. In addition, the weight average molecular weight by GPC is 5300
00, the maximum peak was 1,800,000, and the minimum peak was 19,000. Also, a polymer with a molecular weight higher than the maximum molecular weight peak! The proportion of all ingredients is 25%
Met.

Then, a developer was prepared in the same manner as in the example, and the same test was conducted. The results are shown in Table-3.

(Comparative Example 5) In Example 8, the polymerization initiator 2.2'-azobis(2
, 4-dimethylvaleronitrile) was changed to 2,2'-azobis(2-cyclopropylpropionitrile), and the initial polymerization temperature was changed to 50°C [2,2'-azobis(2-cyclopropylpropionitrile)]. 2,2'-Azobis(2-4-methoxy2
A toner was obtained by carrying out a polymerization reaction in the same manner except that the half-life of 50 DEG C. (4-dimethylvaleronitrile) was approximately 200 minutes.

The obtained toner had a particle size distribution with a volume-based median diameter of 10.3 μm.

Also, the weight average molecular weight by GPC is 1,400,000, the maximum peak is 5,100,000, and the minimum peak is 80.
It was 000. Furthermore, the proportion of high molecular weight components having a molecular weight equal to or higher than that of the maximum molecular weight peak was 15%.

Then, a developer was prepared in the same manner as in the example, and the same test was conducted. The results are shown in Table-3.

(Comparative Example 6) In Example 9, the polymerization temperature was set at 70° C. and polymerization was carried out for 9 hours. [Half-life of 2,2'-azobis(2,4-dimethylvaleronitrile) at 70°C is approximately 40 minutes, 2,2'-azobis(2-methylpropionitrile) (2,2-azobisisobutyro Nitrile) 7
A toner was obtained by carrying out the polymerization reaction in the same manner except that the half-life at 0'C was set to about 400 minutes.

The particle size characteristics of the obtained toner are as follows: median diameter on a volume basis: 1. had a fineness distribution of 9.8 μm. In addition, the weight average molecular weight by GPC is 1,500,000,
Maximum peak is 6.2 million, maximum monthly peak is 120
It was 000. Furthermore, the proportion of high molecular weight components having a molecular weight equal to or higher than that of the maximum molecular weight peak was 17%.

Table 1 shows the 0M results obtained by adjusting Kl of the developer and conducting the same test in the same manner as in the example.

(Comparative Example 7) A toner was obtained in the same manner as in Example 9 except that divinylbenzene as a crosslinking agent was not used.

The particle size characteristics of the obtained toner are the volume-based median diameter D
It had a particle size distribution with a qp of 9.9 μm.

In addition, the weight average molecular weight by GPC is 860,000,
The maximum peak is 1200000 and the minimum peak is 8600
It was 00. Furthermore, the proportion of high molecular weight components having a molecular weight equal to or higher than that of the maximum molecular weight peak was 43%.

In Table 1, cases where the fixability is maintained at 95% or more are marked as ○ and 9.
Δ if it maintains 0% or more, × if it falls below 90%
And so.

Regarding anti-blocking properties, those that collapsed when the cylinder was removed were rated O, those that collapsed when pressed with a finger were rated Δ, and those that did not collapse were rated X.

Regarding abrasion resistance, we observed the state of generation of fine particles in the developing machine and rated it as 1 if no particles were generated, Δ if some particles were generated, and Δ if some particles were generated.
Items that occur frequently are marked as ×.

From Table 1, toner directly obtained by suspension polymerization in which the maximum molecular weight peak is 200,000 or more and the minimum molecular weight peak is 50,000 or less has good fixing properties, offset resistance, blocking resistance, and abrasion resistance. It can be seen that the results are also good.

Furthermore, from Table 2, the toner of Example 5.6.7 has a molecular weight characteristic that satisfies the position of the above peak, and contains low molecular weight polypropylene as a mold release agent, so it is the same as that of Example 1. , 2.3.4 toners can be obtained, and it can be seen that staining of the fixing roller can be effectively prevented.

Regarding the toner of Example 8.9.10.11 and the toner of Comparative Example 5.6.7 shown in Table 3, the copying speed [A
4 horizontal passes, 32 sheets/minute electrophotographic copying machine PC-325
A further 20,000-sheet printing durability test was conducted using No. 5 (trade name). As a result, Example 8.9 was similar to the results shown in Table 3.
．． Toner No. 10.11 gave good results in fixing properties, anti-offset properties, anti-blocking properties, and abrasion resistance, and did not cause roller stains, while Comparative Examples 5.6.
In the case of toner No. 7, the fixing properties were even worse, and the occurrence of cold offset was observed. It was confirmed that the present invention can be applied to copying machines with different copying speeds and different fixing conditions. Furthermore, the Tg of the toner of Example 8.9.10.11
, Ti, and Tm were as shown in Table-4.

[Brief explanation of drawings]

Figure III is a characteristic diagram showing temperature and viscosity changes of toner particles according to the present invention, and Figures 2 to 1 [4 are characteristic diagrams of molecular weight distribution of toner particles according to the present invention.

Claims (13)

[Claims] (1) The volume-based median diameter is in the range of 3 to 20 μm, the molecular weight distribution has multiple peaks, the minimum molecular weight peak position is 50,000 or less, and the maximum molecular weight peak position is 200,000 or more, A toner characterized by being spherical particles obtained by suspension polymerization. (2) The proportion of the high molecular weight component having a peak value of the maximum molecular weight or more is in the range of 10 to 40% of the total, and the particle is composed of spherical particles obtained by suspension polymerization. The toner according to item 1. (3) The toner according to claim 1 or 2, wherein the suspension polymerized particles contain a releasing substance. (4) The temperature at which the toner is heated during fixing to 15
In the 0°C region, the viscosity of the toner increases by 5x due to heating.
4. The toner according to claim 1, wherein the temperature difference required to change from 10^6 poise to 5 x 10^4 poise is 32[deg.] C. or more. (5) The glass transition temperature of the fixing resin is Tg, the outflow start temperature of the toner is Ti, and 1/2 of the toner
When the outflow temperature is Tm, the toner outflow start temperature T
4. The toner according to claim 1, wherein i satisfies the range of Ti-Tg≦50, and the 1/2 outflow temperature Tm satisfies the range of Tm-Ti≧30. (6) The average viscosity gradient (absolute value) of the toner in the temperature range of 100 to 150°C satisfies the range of 0.02 to 0.07/°C, and the absolute value of the viscosity gradient in the temperature range is 0.030. 4. The toner according to claim 1, wherein the toner has at least one region as follows. (7) There are two regions in which the viscosity gradient is 0.030/°C or less, and the temperature in the region is in the range of 115 to 125 °C,
7. The toner according to claim 6, wherein the temperature is in the range of 130 to 140°C. (8) The toner according to claim 6, wherein the toner has a region where the viscosity gradient is slower than the average viscosity gradient of the toner in the temperature region by 10% or more. (9) In a method for producing toner by a suspension polymerization method using a vinyl monomer and a colorant, when polymerizing the vinyl monomer, crosslinking with an initiator having a half-life of 30 minutes or less is performed. 1. A method for producing a toner, the method comprising using a polymer containing an agent and polymerized so that the molecular weight distribution has a plurality of peaks. (10) The method for producing a toner according to claim 9, wherein the vinyl monomer is polymerized by containing a releasing substance in addition to an initiator and a crosslinking agent. (11) When polymerizing the vinyl monomer, two or more initiators and a crosslinking agent having different half-lives are contained, and the half-life of at least one initiator is within 20 minutes, and the molecular weight distribution is 10. The method for producing a toner according to claim 9, wherein a polymer is used which has been polymerized so that a plurality of peaks are obtained. (12) The method for producing a toner according to claim 9, wherein the vinyl monomer and the colorant are polymerized together with at least one of a colorant, a charge control agent, and a magnetic material. . (13) The toner according to any one of claims 9 to 12, wherein polymerization is carried out so that the molecular weight of the minimum peak is 50,000 or less and the molecular weight of the maximum peak is 200,000 or more in the plurality of peaks of the molecular weight distribution. Production method.