JPH01257855A - Toner - Google Patents

Abstract

PURPOSE:To obtain a toner having superior electrostatic chargeability, fixability and cleanability by adhering and fixing fine particles having specified characteristics on the surfaces of core particles contg. a colorant and having specified characteristics. CONSTITUTION:Fine particles having 60-150 deg.C glass transition point (Tg) are adhered and fixed on the surfaces of core particles contg. the colorant and having <=150 deg.C softening point (Tm) and 3,000-20,000 number average molecular weight (Mn) to obtain the toner. The fie particles are firmly fixed on the surfaces of the core particles and the toner has a rugged structure formed by coating the surfaces of the core particles with the fine particles retaining the original spherical shape. The average particle size of the core particles is regulated to <=20mum and that of the fine particles to 0.1-1mum, preferably 0.2-0.8mum. The toner has superior electrostatic chargeability, cleanability and fixability especially at low temp.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a toner for developing electrostatic latent images.

Conventional technology and its problems Conventionally, toner for developing electrostatic latent images is produced by melt-kneading thermoplastic resin, colorant, and other additives, and crushing and classifying the mixture to obtain a desired particle size distribution. Manufactured.

However, it is difficult to reduce the particle size of such pulverized and classified toner, and the shape of each toner is not uniform, resulting in poor fluidity.

Nowadays, as copying machines become more widespread, there is an increasing demand for high-quality images and high-speed development. It is difficult to meet these demands with pulverized and classified toner.

Therefore, instead of the pulverized and classified toner, a suspension polymerization toner has been proposed, which enables the particle size to be reduced and is formed into particles or spheres.

Suspension polymerized toner has a spherical shape, so it has good fluidity.
The small spherical shape makes it suitable for high-quality image formation.

However, when the toner is triboelectrically charged, the probability of contact with the carrier is small due to its shape, resulting in poor triboelectrification.Also, when cleaning the remaining toner on the photoreceptor, the small particle size and spherical shape cause the toner to be used as a cleaning blade. It easily slips between the photoreceptor and has poor cleaning performance.

Further, from the viewpoint of high-speed development and labor saving, toners that can be fixed at low temperatures are desired, but such toners are composed of low softening point resins, have no heat resistance, and cause problems such as toner aggregation.

Problems to be Solved by the Invention The present invention has been made in view of the above-mentioned problems, and takes advantage of the characteristics of suspension polymerized particles and has excellent charging properties, cleaning properties, fixing properties, especially low-temperature fixing properties. The purpose is to provide toner.

As a means to solve the problem, the present invention provides a toner in which microparticles are adhered and fixed to the surface of a core particle containing a colorant, the core particle has a softening point (Tm) of 150°C or less, a number average molecular weight (Mn ) is 3
000-20000, and the glass transition point of microparticles (
The present invention relates to a toner for developing electrostatic latent images, characterized in that Tg) is 60 to 150°C.

Toner for electrostatic charge development, which is made by adhering and fixing fine particles to the surface of a core particle, is made by suspending and polymerizing at least a vinyl monomer in an aqueous solution. It is obtained by free emulsion polymerization and is obtained by adhering and fixing rain particles using a water-soluble initiator.

The toner of the present invention has a structure in which microparticles are firmly attached and fixed on the surface of a core particle, and unevenness is imparted thereto. The unevenness is formed by the fine particles covering the surface of the core particle while maintaining the spherical shape of the fine particles. Due to the unevenness of the toner of the present invention, the probability of contact with the carrier is increased, good charging properties are obtained, and the cleaning properties of the toner are improved.

In the present invention, the core particles and the fine particles are made of materials with different physical properties in order to provide both fixing properties and heat resistance functions.

In order to impart heat resistance, the microparticles are heated to the glass transition point (T
g) is composed of a resin having a temperature of 60 to 150°C, preferably 70 to 140°C. If it is composed of a material with a Tg lower than 60°C, there will be problems with heat resistance and toner aggregation.
If the temperature is higher than 0° C., fixing properties, especially low temperature fixing properties, will be a problem.

In order to provide good fixing properties, the core particles have a softening point (T m
) is 150°C or less, and the number average molecular weight (Mn) is 3
000-20000, preferably 4000-l 200
It is made of a resin with a low softening point of 0.

The objects and effects of the present invention can be achieved when all of the above-mentioned physical properties of the core particles and fine particles are satisfied.

If even one of the above physical properties is not satisfied, a good toner having both heat resistance and fixing properties, especially low-temperature fixing properties, cannot be obtained.

Furthermore, in order to improve the fixing properties of the toner, the number average molecular weight (Mn) of the resin of the core particle is lower than the weight average molecular weight (Mw).
The molecular weight distribution (Mw/Mn) expressed as the ratio to 10
~70, preferably 15-50, more preferably 20~
Adjust it to 40.

Therefore, in the present invention, by composing the microparticles with a heat-resistant resin, it is possible to prepare a toner that has both fixing properties and heat resistance. In particular, the core particle has a softening point of 80
A toner made of a resin having a temperature of 130° C. and a molecular weight distribution of 20 or less, more preferably 10 or less can be fixed under pressure without the need for heating during fixing.

The core particles are formed, for example, by suspension polymerization.

Suspension polymerization is a method in which radical polymerization is carried out by adding a soluble initiator to the monomer while vigorously stirring the polymerizable monomer with a medium that does not dissolve the monomer. The size can be easily adjusted.

The microparticles are produced, for example, by a soap-free emulsion polymerization method.

The soap-free emulsion polymerization method is a formulation in which the emulsifier is removed from the emulsion polymerization system, and the initiator radicals generated in the aqueous phase combine with the seven molecules slightly dissolved in the aqueous phase, which eventually become insolubilized and form particle nuclei. . Particles produced by this polymerization method generally have a larger particle size (0.2 to 1 μm) than those produced by emulsion polymerization, and have a narrower particle size distribution.

The Soapley emulsion polymerization method is based on the above suspension polymerization method using a dispersion medium (
The polymer, which has a low solubility in water (usually water), is dispersed in a dispersion medium by stirring, and polymerization is carried out in each dispersed oil droplet using a polymerization initiator (oil-soluble initiator) that has been dissolved in the monomer in advance. Proceed; (1) In order to prevent coalescence between particles during polymerization, a dispersion stabilizer such as a surfactant is used.10 The particle size varies from I to 100 μm or more, and the particle size distribution is wide.

The soap-free emulsion polymerization method can control the particle size within the range of 0.1 μm to 1 μm, and also achieves particles with a sharp particle size distribution, which cannot be achieved with the suspension polymerization method. Since the particle size and uniformity of the microparticles are required for adhering the microparticles to the surface, the soap-free emulsion polymerization method is used to prepare the microparticles.

When preparing the core particle gauze and fine particles, in addition to the monomer and the polymerization initiator, various other desired additives such as offset inhibitors, charge control agents, and other desired additives may be added. It is more effective to incorporate the anti-offset agent and the charge control agent into fine particles because these additives can perform their original functions.

The size of the core particles is adjusted to have an average particle diameter of 20 μm or less, preferably 2 to 15 μm. If it is larger than 20 μm, the image quality and chargeability will be poor.

The size of the microparticles is such that the average particle size is 0.1μm-1μm1
Preferably 0.2 to 0.8 μm1, more preferably 0.2
~0.6 μm is used. If the average particle diameter of the microparticles is smaller than 0.1 μm, it is difficult to form irregularities on the surface of the core particles for the purpose of the present invention. In addition, from the viewpoint of imparting heat resistance, since the thickness of the fine particle layer is thin, the purpose cannot be sufficiently achieved. When the average particle diameter of the microparticles is larger than 1 μm, it becomes difficult to uniformly adhere the microparticles to the surface of the core particle, the surface coverage rate decreases, and the toner cleanability, durability, etc. are not sufficiently improved. First, when the purpose is to impart heat resistance, the influence of the core particles becomes more likely.

Furthermore, due to the size of the microparticles, it is difficult to firmly adhere and fix the particles to the surface of the core particle.

In preparing the core particles and microparticles of the present invention, the same monomers can be used for both, and examples of such monomers include vinyl monomers, such as styrene,
-Methylstyrene, -Methylstyrene, p-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, pn-butylstyrene, p-tert-butylstyrene, pn~hexylstyrene, 1) n- Octylstyrene, p-n-nonylstyrene, p-n-denlestyrene, 1) n-dozocylstyrene, p-methoxystyrene, p-ethoxystyrene, p-7 enylstyrene,
Examples include styrene and derivatives thereof such as p-chlorostyrene and 3,4-dichlorostyrene, with styrene being the most preferred. Other vinyl monomers include vinyl esters such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl butyrate, methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, methyl α-chloroacrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylate n-butyl methacrylate, isobutyl methacrylate, propyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, methacrylic acid 2
- α-methylene aliphatic monocarboxylic acid esters such as ethylhexyl, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, acrylonitrile, methacrylonitrile acrylamide, etc. (meth)
Acrylic acid derivatives, vinyl ethers such as vinyl methyl ether, vinyl ethyl ether, vinyl isobutyl ether, vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone, methyl isopropenyl ketone,
Examples include N-vinyl compounds such as N-vinylpyrrole, N-vinylcarpazole, N-vinylindole and N-vinylpyrrolidone, and vinylnaphthalenes. The synthetic resin used for the core particles may be a homopolymer in which one of these vinyl monomers is used alone, or a copolymer in which a plurality of these vinyl monomers are used in combination.

In addition, as a vinyl monomer, a monomer component having a nitrogen-containing polar functional group or a fluorine-containing monomer component is used.
It can be used alone or in combination with the monomers mentioned above. When microparticles are composed of monomers having such polar groups, the microparticles themselves function as charge control agents, so the charge control agent can achieve the desired chargeability with a smaller amount than the amount contained in the core particles. It becomes possible to grant.

Nitrogen-containing polar functional groups are effective for positive charge control, and examples of monomers having nitrogen-containing polar functional groups include the following general formula (I) \ (wherein, R1 is hydrogen or a methyl group, R2 and R3 are hydrogen or carbon There are amino(meth)acrylic monomers represented by (1 to 20 alkyl groups, X is an oxygen atom or a nitrogen atom, and Q is an alkylene group or an arylene group).

Representative examples of amine (meth)acrylic monomers include:
N,N-dimethylaminomethyl (meth)acrylate,
N,N-diethylaminomethyl (meth)acryle-1-
1N, N-dimethylamino (meth)acrylate, N,
N-diethylaminoethyl (meth)acrylate, N,
N-dimethylaminepropyl (meth)acrylate, N
, N-dimethylaminobutyl (meth)acrylate, p
-N,N-dimethylaminophenyl (meth)acrylate, p-N,N-diethylaminophenyl (meth)acrylate-1', p-N,N-dipropylaminophenyl (
meth)acrylate, p-N,N-dibutylaminophenyl (meth)acrylate, p-N-laurylaminophenyl (meth)acrylate, p-N-stearylaminophenyl (meth)acrylate, p-N,N-dimethylamino Benzyl (meth)acrylate, p-N.

N-diethylaminobenzyl (meth)acrylate, p
-N,N-dipropylaminobenzyl (meth)acrylate, p-N,N-dibutylaminobenzyl (meth)acrylate, p-N-laurylaminobenzyl (meth)
Examples include acrylate and p-N-stearylaminobenzyl (meth)acrylate.

Additionally, N,N-dimethylaminoethyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)
Acrylamide, N,N-diethylaminopropyl (meth)acrylamide, p-N,N-dimethylaminophenyl (meth)acrylamide, p-N,N-diethylaminophenyl (meth)acrylamide, p-N,N-dipropylaminophenyl (meth)acrylamide, p-
N,N-dibutylaminophenyl (meth)acrylamide, p-N-laurylaminophenyl (meth)acrylamide, p-N-stearylaminophenyl (meth)acrylamide, p-N,N-dimethylaminobenzyl (
meth)acrylamide, p-N, N-diethylaminobenzyl (meth)acrylamide, p-N, N-dipropylaminobenzyl (meth)acrylamide, p-N.

N-dibutylaminobenzyl (meth)acrylamide,
Examples include p-N-laurylaminobenzyl (meth)acrylamide and p-N-stearylaminopencyl (meth)acrylamide.

Fluorine atoms are effective for negative charge control, and there are no particular restrictions on the fluorine-containing atoms. Propyl acrylate, 2.2,3,3,
4,4,5.5-octafluoroamyl acrylate,
Preferred examples include fluoroalkyl (meth)acrylates such as IH, IH, 2H, 2H-hebutadecafluorodenyl acrylate. In addition, trifluorochloroethylene, hynylidene fluoride, trifluoroethylene, 47
Ethylene fluoride, trifluoropropylene, hexafluoropropene, hexafluoropropylene, etc. can be used.

As the coloring agent contained in the core particles in the electrostatic latent image developing toner of the present invention, various organic and inorganic pigments and dyes of various colors as shown below can be used.

That is, examples of black pigments include carbon black, copper oxide, manganese dioxide, aniline black, and activated carbon.

Yellow pigments include yellow lead, zinc yellow, cadmium yellow, yellow iron oxide, mineral fast yellow, nickel titanium yellow, Fuji Blue Yellow, and naphthol yellow 51.
These include Bansar Yellow G1 Bansar Yellow 10G, Benzidine Yellow G1 Benzidine Yellow GR, Quinoline Yellow Lake, Vermai, Nto Yellow NCG, and Tartrazine Lake.

Orange pigments include red yellow lead, molybdenum orange, permanent orange GTR, pyrazolone orange, palkan orange, and industhrene brilliant orange RK.
, Benzidine Orange G1 Indus Thread Brilliant Orange GK, etc.

Red pigments include red pigment, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, lithol red, pyrazolone red, watching red, calcium salt, lake red D1 brilliant carmine 6B, eosin lake, rhodamine lake B1 alizarin lake. , Brilliant Carmine 3B.

Examples of violet pigments include manganese violet, fast violet B1 methyl violet lake, and the like.

Examples of blue pigments include navy blue, cobalt blue, alkali blue lake, hyftria blue lake, 7-talonanine blue, metal-free phthalocyanine blue, partially chlorinated phthalocyanine blue, fast sky blue, and industhrene blue BC.

Examples of green pigments include chrome green, chromium oxide, pigment green B1 micalite green lake, and final yellow green G.

Examples of white pigments include zinc white, titanium oxide, antimony white, and zinc sulfide.

Extender pigments include pallite powder, barium carbonate, clay, silica, white carbon, talc, and alumina white.

In addition, various dyes such as basic, acidic, dispersed, and direct dyes include nigrosine, methylene blue, rose bengal,
They include quinoline yellow and ultramarine blue.

These colorants can be used alone or in combination.

Further, in order to improve developability, magnetic powders such as magnetite, various ferrites, iron, cobalt, and nickel may be added.

In the present invention, the core particles and/or the fine particles, preferably the fine particles, may contain an anti-offset agent.

Examples of the anti-offset agent to be contained in the core particles or microparticles of the present invention include polyolefin waxes such as low molecular weight polypropylene, low molecular weight polyethylene, oxidized polypropylene, and oxidized polyethylene.

Specific examples of polyolefin waxes include, for example:
Hoechst Wax PE520, Hoechst
Wax PE130, Hoechst Wax PE
190 (manufactured by Hoechst), Mitsui Hiwax 200, Mitsui Hiwax 210, Mitsui Hiwax 210M, Mitsui Hiwax 220, Mitsui Hiwax 220M (manufactured by Mitsui Petrochemical Industries), Sunwax 131-P, Sunwax 151-P , non-oxidized polyethylene wax such as Sunwax 161-P (manufactured by Sanyo Chemical Industries, Ltd.), Hoechst Wax PED121, Hoec
hst Wax PED153, Hoechst Wa
x PED521y Hoechst Wax PED
522, Ceridust3620. Ceridus
tVP130, CeridustVP5905, Ce
ridust VP9615A% Ceridust
TM9610F (manufactured by Hoechst), Mitsui Hiwax 420M (manufactured by Mitsui Petrochemical Industries), Sunwax E
-300, oxidized polyethylene wax such as Sunwax E-250P (manufactured by Sanyo Chemical Industries, Ltd.), Ho
echist Wachs PP230 (manufactured by Hoechst), Hiscol 330-P, Bischol 550-P,
Non-oxidized polypropylene wax such as Hiscol 660-P (manufactured by Sanyo Chemical Industries, Ltd.), Viscoll TS
An example is an oxidized polypropylene wax such as -200 (manufactured by Sanyo Chemical Industries, Ltd.).

The wax used in the present invention has a number average molecular weight (
Mn) or I OOO-20000, softening point (Tm) is 8
A temperature range of 0 to 150°C is used.

If Mn is 1000 or less or Tm is 80°C or less, the resin component in the core particles and minute resin particles cannot be uniformly dispersed, and only the wax component is eluted onto the toner surface, causing problems during toner storage or development. This is because there is a risk that not only unfavorable results may be brought about, but also there is a risk of contamination of the photoreceptor such as filming.

In addition, Mn exceeds 20,000 or Tm exceeds 150.
If the temperature exceeds .degree. C., the compatibility with the resin will deteriorate, and the effect of containing wax, such as the high temperature offset method, will not be obtained.

The wax component is particularly preferably added to the fine particles, and the amount added to the fine resin particles is 0.1 to 20% by weight, more preferably 1 to 15% by weight of the total weight of the fine resin particles.
It is preferable that That is, if the amount added is less than 0.1% by weight, sufficient anti-offset effect cannot be exhibited, while if the amount added exceeds 20% by weight, uniform dispersion with the resin component in the micro resin particles may not be achieved. Unable to do it,
This is because only the wax component is eluted onto the toner surface, which may cause unfavorable results during storage or development of the toner, and may cause contamination of the photoreceptor such as filming. Furthermore, even if the amount of wax component added is close to 20% by weight of the fine resin particles, the amount of wax component relative to the entire L-ner particles is still small, and the image quality due to the high content of wax component Problems such as excessive gloss do not occur.

Polyolefin Wanx can be used with other waxes, such as synthetic hydrocarbon waxes such as Finnyar Tropunyu wax: candelilla wax, carnauba wax, rice wanx, water wax, vegetable waxes such as jojoba oil: paraffin wax, micro Petroleum waxes such as Crystan Wax and petrilactam; Modified waxes such as monk wax derivatives, paraffin wax derivatives, and micro Crystan Wax derivatives; Noricone oils such as dimethyl silicone oil and phenylmethyl silicone oil; and various other It may be used together with synthetic waxes such as fatty acids, acid amides, acid imides, esters, ketones, and blends of these various waxes.

As the charge control agent that can be used in the present invention, either a positively chargeable charge control agent or a negatively chargeable charge control agent can be used, depending on the purpose of the toner.

Examples of positively charged charge control agents include ■ Nigrosine Base EX (manufactured by Orient Chemical Co., Ltd.) ■ Quaternary ammonium salt P-51 (manufactured by Orient Chemical Co., Ltd.) ■ Nigrosine Pontron N-0'1 (manufactured by Orient Chemical Co., Ltd.) Co., Ltd.) ■Sudan Chief Schwarz BB (Solvent Black 3: ;Co1or Inde
x 26150) ■Fettschwarz HB N (C
, I, NO, 26150) ■ Brilliant Spirits Schwarz TN (manufactured by Methylpen Fabriken Bayer) ■ Sapon Schwarz Also, as a negatively charged charge control agent, ■Oil black (Color Index 2615
0) Oil black BY (manufactured by Orient Chemical Co., Ltd.) ■Pontron S-22 (manufactured by Orient Chemical Co., Ltd.) ■Salicylic acid metal complex E-8 1 (manufactured by Orient Chemical Co., Ltd.) ■Thioindigo pigment ■Copper phthalocyanine Sulfonylamine derivative ■ Spiron black TRH (manufactured by Hodogaya Chemical Co., Ltd.) ■ Pontron S34 (manufactured by Orient Chemical Co., Ltd.) ■ Nigrosine s.

(manufactured by Orient Chemical Co., Ltd.) ■ Ceres Spartz (R) G (Methylpen Fabriken Bayer W) [Phase] Chromogen Schwarz ETOO (c, I, NO,
14645) ■Azo Oil Black (R) (manufactured by Nanyonal Aniline).

When the fine resin particles are neutral to the carrier, it is desirable to add a charge control agent to the fine resin particles.

These charge control agents can be used alone or in combination, but the amount of charge control agent added to the microparticles constituting the outer shell layer is 100 parts by weight of the synthetic resin forming the microparticles. 0.001-10 parts by weight,
Preferably it is 0.01 to 5 parts by weight. That is, if the amount added is less than 0.001 parts by weight, the amount of charge control agent present on the surface of the toner particles is small, resulting in insufficient charge of the toner, while if it exceeds 10 parts by weight, This is because there is a risk that the charge control agent may peel off from the shell layer and become spent on the surface of the carrier, or be mixed into the developer, deteriorating printing durability.

In order to adhere and fix the microparticles to the surface of the core particles, a predetermined amount of the core particles and microparticles are dispersed in an aqueous solution, and a water-soluble polymerization initiator is added.

The fine particles form the outer shell layer of the core particles, and the amount of the fine particles added is 5 to 20 parts by weight, preferably 8 to 15 parts by weight, based on 100 parts by weight of the core particles. If the amount of fine particles added is less than 5 parts by weight, the surface of the core particles will not be completely covered, resulting in poor heat resistance and
Cleanability and chargeability are adversely affected, and if the amount exceeds 20 parts by weight, the fine particles that cannot be coated adversely affect fluidity and chargeability.

Examples of water-soluble polymerization initiators include ammonium persulfate, potassium persulfate, 2,2'-azohis (N,N'-dimethyleneisobutyramidine) hydrochloride, 2゜2''-azohis (2
-amidinopropane) hydrochloride, ferrous sulfate or hydrogen peroxide.

The fine particles can be attached to the surface of the core particle simply by mixing and stirring both the core particle and the fine particle, but using a water-soluble polymerization initiator makes the attachment stronger and makes drying and classification easier. Sometimes, the microparticles can be fixed so that they do not detach from the surface of the core particle. One reason for this is thought to be that the water-soluble initiator initiates polymerization of unreacted monomers in both the core particle and the microparticle, and the two particles are molecularly bonded through the polymerization reaction. .

The conditions for adhering and fixing the microparticles to the core particle surface, such as the amount of water-soluble initiator added, temperature, reaction time, etc., depend on the type of monomer used to form the core particle and microparticles, and the radical polymerization initiator. Taking into consideration various conditions such as reaction time, etc., conditions may be appropriately selected to ensure that the fine particles are firmly adhered and fixed to such an extent that they are not adversely affected by detachment of the fine particles from the core particle during actual use.

Illustratively, the water-soluble initiator is added to the core particles obtained by suspension polymerization from 0.1% to 20% by weight, preferably from 1% to 10% by weight, more preferably from 2% to 5% by weight. % by weight may be added at a temperature of 60 to 80° C. for about 3 to 5 hours. If the amount of water-soluble initiator added is less than 0.1% by weight, detachment of microparticles from the core particles after drying becomes a problem, and if it is more than 20% by weight, aggregation of the core particles and microparticles occurs.

The toner of the present invention can be mixed with a suitable carrier to form a two-component developer. Known carriers can be used, and the toner is usually blended in an amount of 3 to 12% by weight of the developer.

A fluidizing agent may be added (externally added) to the toner of the present invention to improve fluidity. Silica as a fluidizing agent,
Examples include aluminum oxide, titanium oxide, silica, eye oxide, miniram mixture, silica/titanium oxide mixture, and the like.

Further, in order to improve cleaning performance, a metal soap such as zinc stearate may be externally added.

The present invention will be explained below using examples.

Manufacturing method of core particles Manufacturing of core particles A Styrene 160g, butyl methacrylate 90g, imbutyl acrylate 3g, lauryl mercaptan 2g,
2 g of silane coupling agent [TSL8311 (manufactured by Toshiba Silicone Co., Ltd.)], 109 g of carbon black [#2300 (manufactured by Mitsubishi Kasei Corporation)], and 6 g of 2,2'-azohis (imbutyronitrile) were mixed with a homojetter (manufactured by Tokushu Kika Kogyo Co., Ltd.). )
The mixture was mixed and dispersed to obtain a uniform mixed dispersion. Next, as a dispersion stabilizer, 60 g of a 4% solution of methyl cellulose (35 LV in Methocel + manufactured by Dow Chemical Co., Ltd.), 60 g of a 4% solution of methylcellulose, and 0TP-75
: 5 g of 1% solution (manufactured by El Hikari Chemical Co., Ltd.), 0.3 g of sodium hexametaphosphate (manufactured by Wako Pure Chemical Industries, Ltd.) and 6 g of ion-exchanged water.
Using a homojetter, the homogeneous dispersion liquid was suspended in water by adjusting the rotation speed of the homojetter so that the average particle size was 5 to 15 μm.

The suspension was transferred to four Lof flasks, and after nitrogen purging, polymerization was carried out at a temperature of 60°C and a stirring speed of 1100 rpm for 24 hours, resulting in a solid content of 26%, a glass transition point (Tg) of 53°C, and a softening point (Tm) of 80°C. 1Mn-10000, Mw/Mn=22
, core particles A having an average particle diameter of 11 μm were obtained. In addition, the measurement of each physical property was performed by the method described below.

Solid content: Measured using a Yamazaki infrared moisture meter.

Glass transition point (Tg): Measured using a differential thermal balance.

Softening point (Tm): Measured using a perfect oven.

Number average molecular weight (Mn): Measured using an osmotic pressure method.

Weight average molecular weight (Mw): Measured using ultracentrifugation.

Average particle size: Measured using Coulter counter method.

Production of core particle B: 3 g of butyl mercaptan instead of lauryl mercaptan
Core particles B were prepared in the same manner as in the production of core particles A, except that .

Core particle B has an average particle size of 11 μm, solid content of 26%, and Tg of 52.
℃1 Softening point 65°O, Mn=8000, Mw/Mn-3
It was 5.

Production of core particles C. Non-core particles using 160 g of styrene, 80 g of butyl methacrylate, 2 g of lauryl mercaptan, 1 g of Nran coupling agent, 8 g of pigment (red), and 3 g of 2,2''-azohis (2゜4-dimethylvaleronitrile). Colored core particles C were obtained in the same manner as in the manufacturing method of A. Core particles C had an average particle size of 11 μm, solid content of 24%, Tg of 710C, and a softening point of 120.
℃, Mn=12000, Mw/Mn-40.

Production of core particles 160 g of styrene, 90 g of butyl methacrylate, 20 g of inbutyl acrylate, 2 g of butyl mercaptan, 1 g of silane coupling agent, 1 Og of carbon black, 2
．． 2'-azobis(2,4-dimethylvaleronitrile)
Core particles were obtained in the same manner as in the production of core particles A using 6 g. Core particles have an average particle size of 11 μm, solid content of 29%, and T
g58°C1 Softening point 90°O, Mn=9000, Mw/M
n=37.

Production of Core Particles E Core Particles E were produced in the same manner as in the production of Core Particles C, except that α-methylstyrene dimer (manufactured by NOF Corporation) Ig was used instead of lauryl mercaptan. Core particle E has an average particle size of 11 μm, solid content of 27%, Tg of 71'O, and a softening point of 1.
The temperature was 50°O, Mn=17000, and Mw/Mn=35.

Production of core particle F: butyl mercaptan 2 instead of lauryl mercaptan
g, α-methylstyrene dimer (manufactured by NOF Corporation) 3 g
Core particles E were produced in the same manner as core particles C, except that . Core particles F have an average particle diameter of 1] pm, solid content of 2
6%, Tg 71°C 1 Softening point 50°O, Mn-7000,
Mw/Mn=85.

Production of core particles G Core particles G were produced in the same manner as in the production example of core particles B, except that 160 g of styrene and 70 g of butyl methacrylate were used. Core particles G have an average particle size of 11 μm, solid content of 26%, and T
g74℃1 Softening point 155°O, Mn-13000, Mw
/Mn=45.

Production of Core Particles H- Core particles were produced in the same manner as in the production of Core Particles A, except that the amounts of monomer compositions shown in Table 1 below were used in the production of Core Particles A, and the following properties (average particle diameter, Solid content, Tg, Tm,
Core particles HK having Mn, Mw/Mn) were obtained.

Table 1 Core particles HIJK Styrene 10 50 100 105
butyl methacrylate) 20
30 50 90 Isobutyl methacrylate 260 160
60 30 stearyl methacrylate)
5 20 -
-Particle size Cp+++) 11 11 12
12 Solid content 30 28 22
24Tg (℃) -34-1230
53Tm('C) 48
50 67 80Mn
6500 8000 7
800 9500Mw/Mn
28 40' 35
33 Table 2 summarizes the physical properties of core particle A-.

Table 2 (Core particle physical properties) 0.4 g of ammonium persulfate was dissolved in 800 g of ion-exchanged water, transferred to a four-hole flask, and heated to 75°C while purging with nitrogen. was added and polymerized for 6 hours at a stirring speed of 30 Q rpm to obtain uniform particles a with an average particle size of 0.3 μm. The glass transition point of microparticles a was 108°C.

Production of microparticles 2. 0.3 g of 2'-azobis(2-amidinopropane) dihydrochloride was dissolved in 800 g of ion-exchanged water, transferred to a four-bottle flask, and heated to 70°C while purging with nitrogen. A solution of 200 g of methyl methacrylate was added and polymerized for 3 hours at a stirring speed of 20 Orpm to obtain uniform particles with an average particle size of 0.4 μm. The glass transition point of the microparticles was 1050C.

Production of microparticles C 0.2 g of ammonium persulfate was dissolved in 800 g of ion-exchanged water, transferred to a four-bottle flask, heated to 70°C while purging with nitrogen, and 200 g of styrene was added dropwise over 2 hours using a dropping funnel. After the completion of dropping, polymerization was carried out for 4 hours to obtain uniform particles C with an average particle size of 0.8 μm. The glass transition point of the microparticles C was 1.5°C.

Production of microparticles d In a nitrogen-substituted four-bottle flask, 200 g of slurry containing 20% of 0.4 μm microparticles was added 7 mL of ion-exchanged water.
60g of methyl methacrylate was added thereto, and while stirring at 300 rpm, 280g of methyl methacrylate containing 3g of 2,2-azohisisobutyronitrile was added dropwise over 1 hour.
Keep time, average particle size l.

Uniform particles d of 2 μm were obtained. The glass transition point of the microparticles d was 105°C.

Production of microparticles e In the method for producing microparticles a, the stirring speed during granulation is set to 1.
The average particle size was 0 using the same composition method except that the rpm was 1000 rp.
．． Uniform particles e of 1 μm were obtained. The glass transition point of the microparticles e was 108°C.

Production of microparticles f In the method for producing microparticles a, microparticles f with an average particle size of 0.3 were produced in the same manner as in the production of microparticles A, except that 45g of isobutyl acrylate was used instead of 100g of methyl methacrylate and 1 methacrylic acid. did. microparticle f
The glass transition point of was 44°C.

Production example of toner Production of toner I 26% slug of core particle A - 20 g of microparticle A
% slurry was added and dispersed in 100g of ion-exchanged water, and 5g of ammonium persulfate was added. The dispersion was transferred to four flasks and heated at 70℃ under nitrogen atmosphere.
The mixture was reacted for 5 hours at a stirring speed of 160 rpm, filtered, washed with water, and dried to obtain resin microspheres with an average particle size of 10 to 20 μm.

The resin microspheres had a softening point of 60° C. and an angle of repose of 21°, and no aggregation was observed even when they were left at 50° C. overnight. Here, the obtained particles were further subjected to air classification to obtain toner I having an average particle size of 11.5 μm.

Preparation of Toners 2 to 12 Toners 2 to 12 were obtained in the same manner as Toner 1 except that the core particles and fine particles were changed as shown in Table 3.

FIG. 1 shows a photograph showing the particle structure of Toner 2. The size scale is shown in the photo.

Toner 13 Toner 13 was made of only core particles A without any fine particles attached.

FIG. 2 shows a photograph showing the particle structure of toner 13. The size scale is shown in the photo.

Preparation of Toners 14 to 17 Toners 14 to 17 were obtained in the same manner as Toner J except that the core particles and fine particles in Production Example 1 of Toner I were changed as shown in Table 3.

Production of Toner 18 Toner 18 was obtained in the same manner as in the production of Toner 1 except that the ammonium persulfate salt was omitted.

FIG. 3 shows a photograph showing the particle structure of toner 18. The size scale is shown in the photo.

(Hereafter, blank spaces) Table 3 Polyester resin 100 (softening point, 123°C; glass softening point, 65°O, AV23.0HV40) Inorganic magnetic powder 500 (manufactured by Toda Kogyo Co., Ltd.: EPT-1000) Carbon black
2 (manufactured by Mitsubishi Kasei Corporation: MA#8) The above materials were thoroughly mixed and pulverized using a Henschel mixer, and then the cylinder part 18000. Cylinder head section"7
The mixture was melted and kneaded using an extrusion kneader set at 0°C. After cooling, the kneaded material was finely pulverized using a jet mill, and then classified using a classifier to obtain a magnetic carrier having an average particle size of 55 μm.

Predetermined toners 1-13 shown in Table 4 and the above carrier were mixed at a ratio of toner/carrier of 7/93, and colloidal silica R-972 was added to 100 parts by weight of the toner.
(manufactured by Nippon Aerosil Co., Ltd.): A two-component developer was prepared by post-processing with 0.1 part by weight, and the evaluation described below was performed.

Note that EP-5707 (manufactured by Minolta Camera Co., Ltd.) is used for the developer in combination with the -chargeable toner, and EP-470Z is used for the developer in combination with the +chargeable toner.
(manufactured by Minolta Camera Co., Ltd.) was used for evaluation. In addition,
The results of each evaluation are shown in Table 4.

(2) Image quality evaluation As described above, images were printed using the above-mentioned copying machine using various toner and carrier combinations. As for the conditions, a standard chart from Dataquest Inc. was copied under appropriate exposure conditions, and the image quality was evaluated using the method described below.

Image quality is evaluated using the Dataquest standard chart.
Ranking was performed based on a comprehensive evaluation of gradation, resolution, line reproducibility, fineness of image texture, etc.

Furthermore, in this image evaluation, the degree of gloss was visually judged, and appropriateness and inappropriateness were also included in the evaluation criteria.

Both image quality and glossiness are ranked △ and can be used for practical purposes, but ◯ is desirable (Table 4).

(2) Printing durability test Using the developer shown in Table 4, a printing durability test of 10,000 sheets was conducted.

At this time, the toner charge amount and fog were evaluated.

Furthermore, the degree of contamination on the surface of the photoreceptor was also evaluated. △It is desirable that it is practically usable or O at rank or higher (
Table 4).

(2) High-temperature offset resistance The temperature of the fixing device of EP'-570Z and EP-470Z was varied and images were produced in the same manner as in the image quality test, and the occurrence of offset was visually determined.

The evaluation is ◎ for a fixing roller at 240'O with no offset occurring, ○ for a fixing roller at 220℃ with no offset occurring, △ for a fixing roller at 200℃ and no offset occurring, and △ for a fixing roller at 200℃. Those in which offset occurred with the roller were rated x (Table 4).

(2) Heat Resistance Test 5g of each toner was placed in a 50cc polyethylene bottle, and the toners were stored in an environment of 50°C for 24 hours, and then evaluated based on their cohesiveness and ranked. Δ or more is practically possible, or O is the preferred range (Table 4).

(2) Cleanability When evaluating the image quality in (1) above, the images were ranked visually based on the degree of cleaning defects that occurred on the images. ○ indicates that no cleaning defects occurred during printing, △ indicates that cleaning defects did not occur at the beginning but cleaning defects occurred during printing, × indicates that cleaning defects occurred in the early stages. (Table 4).

■ The initial image of Kani-Kan was copied onto paper and an OHP sheet, and the fixability was evaluated. The fixing strength is ◎, ■5 to 20 times when the image does not become distorted even after rubbing with a sand eraser for 20 times or more.
○ for 5 to 15 times, △ for 5 to 15 times, × for less than that (Table 4)
.

■ 1 jaw l The results are shown in Table 4.

Table 4 In Table 4, in Examples 7 and 8, various evaluations were performed using EP-470, which was modified by replacing the fixing device with a heat roll and using a pressure fixing device with a surface pressure of 150 kg/cm 2 .

Regarding Example 9, various evaluations were performed using EP-870Z with an improved system speed of 45 cm/sec (however, the heater capacity of the fixing device was not changed).

Effects of the Invention The toner of the present invention has excellent charging properties, fixing properties, cleaning properties, and heat resistance. It has particularly excellent fixing properties.

[Brief explanation of the drawing]

FIG. 1 is a photograph showing the particle structure of toner 2. FIG. FIG. 2 is a photograph showing the particle structure of the toner 13. FIG. 3 is a photograph showing the particle structure of toner 18. Patent applicant: Matsumoto Yushi Pharmaceutical Co., Ltd. Representative Patent Attorneys Aoyama Aoyama 2 Idiots Figure 1 Figure 3

Claims (1)

[Claims] 1. In a toner made by adhering and fixing fine particles to the surface of a core particle containing a colorant, the softening point (Tm) of the core particle is 1.
50℃ or less, number average molecular weight (Mn) 3000-200
00, and the glass transition point (Tg) of the microparticles is 60~
A toner characterized by a temperature of 150°C.