JPH03101746A - Toner for developing electrostatic charge image and production thereof - Google Patents

Abstract

PURPOSE:To obtain the toner for developing electrostatic charge images which is good for smell by incorporating a binder resin and coloring agent into the toner and specifying the content of aldehyde monomers. CONSTITUTION:The content of the aldehyde monomers in the toner for developing electrostatic charge images contg. at least the binder resin and the cooring agent is specified to <=0.005wt.%. The coloring agent and the binder resin contg. <=0.01wt.% aldehyde monomers are melted and kneaded under heating and after cooling, the mixture is ground to produce the toner at the time of producing the toner for developing electrostatic charge images. The amt. of the aldehydes remaining in the toner is, therefore, decreased and the toner which is good to smell is thereby obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a toner for developing electrostatic images used in electrophotography, electrostatic recording, magnetic recording, and the like.

[Prior Art] Conventionally, as an electrophotographic method, U.S. Patent No. 2,297,6
Although many methods are known, such as Japanese Patent Publication No. 91, Japanese Patent Publication No. 42-23910, and Japanese Patent Publication No. 43-24748, they generally utilize a photoconductive substance and apply it on a photoreceptor by various means. After forming an electrical latent image, then developing the latent image using a developer, and transferring the developer image to a transfer material such as paper as necessary, heat, pressure, heat pressurization, solvent vapor, etc. It is used to fix images and obtain copies. Further, when a step of transferring a developer image is included, a step for removing residual developer is usually provided.

Development methods for visualizing electrical latent images using a developer include, for example, the magnetic brush method described in U.S. Pat. No. 2,874,063, and the magnetic brush method described in U.S. Pat. No. 2,618,552. Cascade development method and 2,221,
The powder cloud method described in US Pat. No. 776, and the method using a conductive magnetic developer described in US Pat. No. 3,909,258 are known.

As the developer applied to these developing methods, fine powders in which dyes and pigments are dispersed in natural or synthetic resins have conventionally been used. For example, particles obtained by dispersing a colorant in a binder resin such as polystyrene and pulverizing the particles to about 1 to 30 μm are used as a developer. As the magnetic developer, one containing magnetic particles such as Magnetite 1 is used. On the other hand, in the case of a system using a so-called two-component developer, the developer is usually mixed with carrier particles such as glass beads and iron powder.

Today, such recording methods are widely used not only for general copying machines, but also for computer output, microfilm printing, and the like. As a result, the required performance has become more advanced, and various performances such as smaller size, lighter weight, lower energy consumption, less maintenance, and more personalization are now required at the same time. In order to satisfy these requirements, requirements for developers have become more stringent in various respects.

For example, as mentioned above, as the range of applications expands and it is used in general offices and homes, it is necessary to pay attention not only to the safety of the developer as a material, but also to the odor generated during fixing. has become necessary. Additionally, copying machines, printers, etc. are often equipped with filters for deodorization, that is, to absorb odors, ozone, etc., but this is disadvantageous in terms of production costs, and it is difficult to maintain deodorization performance. Therefore, there is the hassle of periodic replacement.

Regarding this odor issue, it is obviously an important issue considering the standpoints of users and manufacturers as mentioned above.
Generally speaking, it is not technically easy to fix a developer, which contains a synthetic resin as a main component and fixes it on a transfer material such as paper by utilizing the softening and melting of the synthetic resin upon heating. Further, in order to solve this problem, there is no point in reducing development characteristics such as image quality or developer durability.

Various methods have been considered in order to satisfy these performances at the same time. However, the method of adding additives complicates the system and often causes unexpected problems.

Therefore, it is desirable to improve the binder resin itself.

For this purpose, it is thought that it is good to reduce the residual amount of odor-causing solvents and polymerizable monomers in the binder resin.
To date, various methods have been proposed for this purpose, including effects on other development characteristics.

For example, in JP-A No. 55-155632, a polymer in which the content of the solvent or polymerizable monomer used to obtain the polymer is less than 0.1% by weight is used as a binder resin for a developer. Occurrence of offset, storage stability,
It has been proposed to improve fluidity etc.

In JP-A-53-17737, there is a statement that residual polymerizable monomers affect the triboelectric charging properties, blocking properties, and fixing properties of the developer, and it is necessary to obtain a polymer as a binder resin for the developer. It has been proposed to reduce the amount of residual solvent or polymerizable monomer used for this purpose.

In JP-A No. 64-70765, in particular, in order to deal with problems such as emitting an odor during melting and cross-fertilization, which worsens the worksite environment, or emitting an odor during copying, which causes discomfort, a developer with residual monomers of 200 ppm or less is proposed. Proposals have been made for resins for use as agents. Residual monomer amount is 200ppm
It is stated that if this value is exceeded, blocking resistance and vinyl chloride plasticizer resistance will decrease, and odor problems will remain.

However, when specifically targeting the problem of odor,
Considering the future expansion of the application range of electrophotography, electrostatic recording, etc., it cannot be said that simply reducing the amount of remaining polymerizable monomer is sufficient.

In general, solution polymerization methods, bulk polymerization methods, suspension polymerization methods, etc. are known as polymerization methods for binder resins for developers.
As proposed in No. 57358, there is no need to remove the solvent, there is no need for a powerful stirring device, and the production is easy. This method is suitable as a method for polymerizing a binder resin for a developer, which can be contained in an arbitrary amount.

However, in the suspension polymerization method, the resin is obtained in the form of beads, so there is no step of removing the solvent or polymerizable monomer while the resin is in a molten state, as in solution polymerization, and the method is used only for the purpose of removing water. Only a drying process is performed. As a result, residual amounts of the solvent and polymerizable monomer tend to increase, and special attention must be paid to the odor problem mentioned above.

[Problems to be Solved by the Invention] An object of the present invention is to improve the above-mentioned drawbacks and provide a toner for developing electrostatic images with good odor.

In particular, it is an object of the present invention to provide a toner for developing electrostatic images containing a binder resin that is polymerized in an aqueous medium and having a good odor.

Another object of the present invention is to provide a toner that satisfies excellent performance not only in odor but also in other properties.

[Means and effects for solving the problems] An object of the present invention is to provide a toner for developing electrostatic images containing at least a binder resin and a colorant, in which the content of aldehyde monomers is 0.
, 005% by weight or less.

Furthermore, a method for producing an electrostatic image developing toner containing at least a binder resin and a colorant, which comprises melt-kneading, cooling, and pulverizing. This is achieved by

Here, the binder resin has a content of aldehyde monomers produced by a suspension polymerization method of 0. 0.01% by weight or less of styrenic resin is preferred.

As a result of intensive studies by the present inventors on the factors that affect the odor of toner, it is obvious that the amount of solvent and polymerizable monomer remaining in the toner is effective, as has been known so far. More than that, their oxidation products,
In particular, the residual amount of aldehydes generated by air oxidation of polymerizable monomers has a large influence, and it is believed that reducing the residual amount of aldehydes in toner is the best way to prevent odor in toner. I was convinced.

In particular, benzaldehyde, which is produced by air oxidation of styrene monomers and is caused by styrene polymers or copolymers most commonly used as binder resins for toners, is the component that causes the most odor problems, so the residual amount of benzaldehyde is the most problematic component. We need to be very careful about reducing this.

According to studies by the present inventors, the content of such aldehydes in toner is 0. 0.005% by weight or less, particularly preferably 0.005% by weight or less. The content is preferably 0.04% by weight or less. The content of aldehydes is 0. When the amount exceeds 0.005% by weight, the odor of the toner often becomes noticeable.

In view of this problem, the inventors of the present invention have made extensive studies to reduce the amount of aldehydes, and have found that the objective can be achieved by adopting the method described below.

That is, the aldehydes contained in the toner originate from the binder resin, which is the main component of the toner.
In particular, when the binder resin is produced by suspension polymerization and is suitable for use as a toner, it is contained significantly. Therefore, it is essential to reduce the amount of aldehyde contained in the binder resin. In particular, in order to reduce the amount of aldehyde contained in the binder resin produced by suspension polymerization, by minimizing the amount of dissolved oxygen in the water used during suspension polymerization,
Air oxidation of the polymerizable monomer is suppressed, and as a result, the production of aldehydes is suppressed.

In other words, it has been known in the past that in suspension polymerization methods, the atmosphere in the polymerization system is replaced with nitrogen for the purpose of reducing wasteful consumption of polymerization initiators, but the purpose of this is to reduce the polymerization yield. This is not sufficient to aim at reducing aldehydes. It has been discovered that in order to achieve a reduction in aldehydes, it is necessary to reduce dissolved oxygen in the water used during suspension polymerization. Its mechanism of action is thought to be as follows. In other words, in suspension polymerization, a polymerization reaction occurs within droplets of polymerizable monomers suspended in water, and in this polymerization reaction, the droplets of polymerizable monomers come into direct contact with water, and the droplets in the aqueous phase It is thought that it is strongly affected by dissolved oxygen.

As a specific method for reducing dissolved oxygen, various known techniques can be used, but it is preferable to install a nitrogen introduction pipe into the water and flow nitrogen into the water to efficiently remove dissolved oxygen. A method to reduce it is better.

Further, the suspension of the polymer thus obtained was heated to about 70°C.
It is also possible to carry out a method of heating at the above temperature and simultaneously distilling off the remaining monomers at the same time as water distillation.

As mentioned above, reducing the aldehydes contained in the binder resin is the most effective thing to do. When hot-melting and kneading, it is also effective to take measures such as heating strongly or removing volatile components by suction.

The amount of aldehydes in the developer is determined by the following method using a gas chromatograph.

2. Use 55 mg of DMF as an internal standard and add 100 mp of acetone to prepare a solvent containing an internal standard. Next, 200 mg of the toner binder resin is dissolved in 10 ml of the above solvent. After applying it to an ultrasonic shaker for 30 minutes, leave it for 1 hour. Then 0. Pass through the i door with a 51Lm filter. The amount of sample to be implanted is 4 μ2.

The conditions for gas chromatography are: - Cavillary column (30m x 0.249mm,
DBWAX, film thickness 0.25ILm) ・Detector FID, nitrogen pressure 0. 45kg/cm2, injection concentration 200°C, detector temperature 20
The column temperature is set at 0°C and raised from 50°C at a rate of 5°C/l min for 30 minutes.

・Preparation of calibration curve Add the same amount of DMF as the sample solution. A standard sample prepared by adding the target aldehyde to an acetone solution was similarly measured by gas chromatography, and the aldehyde and internal standard DM
Find the weight ratio/area ratio of F.

Furthermore, in order for the developer of the present invention to have highly satisfactory offset resistance, fixing properties, filming properties on photoreceptors, fusion properties, image properties, etc., the applicant of the present invention disclosed Japanese Patent Application No. 62-57358.
As proposed in the above issue, the binder resin contains 10 to 70% by weight (preferably 10 to 60%) of the tetrahydrofuran (TIIF) insoluble content, and the THF soluble content of G
In the molecular weight distribution by PC, l+lw/Mn≧5, has at least one peak in the region of 2000 to 10,000, and has a molecular weight of 15,000 to 100,000.
A toner binder resin having at least one peak or shoulder in the 00 region and having a molecular weight of 10,000 or less in an amount of 10 to 50% by weight based on the resin is preferred.

The THF-insoluble content in the present invention refers to a gel component that has been crosslinked and becomes insoluble in THF in the resin composition constituting the developer, and this weight ratio is determined by the crosslinking of the resin composition containing the highly crosslinked component. It can be used as a parameter to indicate the degree of The THF-insoluble content is defined by the value measured as follows.

That is, if the developer is a non-magnetic toner, the pigment content, etc., and if the developer is a magnetic toner, the pigment and magnetic substance content, etc. are measured in advance by a known method. Next, a fixed amount of 0.5 to 1.0 g of developer was weighed out (w + g), put into a thimble filter paper (No. 86R manufactured by Toyo Roshi), applied to a Soxhlet extractor, and mixed with 100 to 200 g of chloroform as a solvent.
mj) for 6 hours, evaporate the extracted soluble components with a solvent, vacuum dry at 100°C for several hours, and weigh the amount of THF-soluble resin components (Lg).
Of the pigments and magnetic materials contained in the certain amount of developer, if the weight of the component soluble in THF is W3g and the weight of the component insoluble in THF is W4g, the resin composition is calculated according to the following formula. The TI{F insoluble content in the product is calculated.

THF insoluble matter content = (W, -W2-W.)/<W. -W3-W
4) The evaporated dry product of the solvent-soluble component obtained by the operation of X 100 (%) or less is THF (tetrahydrofuran).
After dissolving in and passing through a sample processing filter,
Use as a GPC sample.

Further, in the present invention, the molecular weight of a chromatographic peak and/or shoulder by GPC (gel permeation chromatography) is measured under one of the following conditions.

That is, the column was stabilized in a heat chamber at 40°C, and THF was added to the column at this temperature as a solvent.
(Tetrahydrofuran) is flowed at a flow rate of 1 ml per minute, and 50 to 200 volumes of a THF sample solution of the resin adjusted to a sample concentration of 0.05 to 0.1% by weight are injected and measured. In measuring the molecular weight of the sample, the molecular weight distribution of the sample was calculated from the relationship between the logarithm value and the count number of a calibration curve prepared using several types of monodisperse polystyrene standard samples. As a standard boristyrene sample for creating a calibration curve,
For example, Pressure Chemical Co. or manufactured by Toyo Sorug Kogyo Co., Ltd., with a molecular weight of 6 x 102,
2. IX 1034 X 10'1.75X 10',
5. IX 10', 1. IX 10', 3.9X
10'', 8.6 xlO', 2 xlO',
It is appropriate to use at least 10 standard boristyrene samples with a diameter of 4.48 xl06. Further, an RT (refractive index) detector is used as a detector.

In addition, in order to accurately measure the molecular weight range of 103 to 4 x 106, it is recommended to use a combination of commercially available polystyrene gel columns, such as Water column.
U-styrage L 500, 103.1 manufactured by S company
0', 10' combination, Showa Denko Shode
xKF-80M, KF-802, 803, 804
, 805 (7) Combination or Toyo Soda's Ding S
Kgel GIOOOH, G2000H, G2500
H, G30001{, G4000H, G5000H
, G6000H, G7000H, and GMH are preferred.

The weight percent of the binder resin of the present invention having a molecular weight of 10,000 or less is determined by the molecular weight 1 of the chromatogram determined by GPC.
Cut out less than 0,000, molecules! The weight ratio with 10,000 or more cutouts is calculated, and the weight % of the THF-insoluble content is used to calculate the weight % with respect to the entire binder resin.

The resin composition in the toner of the present invention is preferably one obtained by polymerizing one or more monomers selected from styrenes, acrylic acids, methacrylic acid granules, and derivatives thereof in view of development characteristics, charging characteristics, and the like. Examples of monomers that can be used include styrene, α-methylstyrene, vinyltoluene, chlorostyrene, and the like.

Acrylic acids, meccrylic acids and their derivatives include acrylic acid, methyl acrylate, ethyl acrylate,
Probyl acrylate, butyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, n acrylate
Acrylic acid esters such as -tetradecyl, acrylic un-hexadecyl, lauryl acrylate, cyclohexyl acrylate, diethylaminoethyl acrylate, and dimethylaminoethyl acrylate, as well as methacrylic acid, methyl methacrylate, ethyl methacrylate,
Probyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, 2-methacrylate
Ethylhexyl, octyl methacrylate, decyl methacrylate, dodecyl methacrylate, lauryl methacrylate, cyclohexyl methacrylate, phenyl methacrylate, 2-hydroxyethyl meccrylate, 2-methacrylate
Examples include methacrylic acid esters such as -hydroxybutyvir, dimethylaminoethyl methacrylate, glycidyl methacrylate, and stearyl methacrylate. In addition to the above-mentioned monomers, small amounts of other monomers may be used as long as the objects of the invention are still achieved, such as acrylonitrile, 2-vinylpyridine, 4-vinylpyridine, vinylrubazole,
Vinyl methyl ether, butadiene, isobrene, maleic anhydride, maleic acid, maleic acid monoesters, maleic acid diesters, vinyl acetate, etc. may be used.

The crosslinking agent used in the toner resin of the present invention includes:
Divinylbenzene, bis(4-
Acryloxyboriethoxyphenyl)propane, ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,5-pentanediol diacrylate, 1
, 6-hexanediol diacrylate, neobentyl glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate,
Tetraethylene glycol diacrylate, polyethylene glycol #200, #400, #600 diacrylates, dibropylene glycol diacrylate, polybropylene glycol diacrylate, polyester diacrylate (MANDA Nippon Kayaku), and the above acrylates. Examples include those that have been replaced with methacrylate.

As polyfunctional crosslinking agents, pentaerythritol triacrylate, trimethylolethane triacrylate, trimethylolpropane triacrylate, tetramethylolmethanetetraacrylate, oligoester acrylate and its methacrylate, 2,2-bis(4-methacryloxy, polyethoxyphenyl) ) Broban, diallyl phthalate, triallyl cyanurate, triallyl asocyanurate, triallyl isocyanurate, triallyl trimellitate, diaryl chlorendate, and the like.

The method for synthesizing the binder resin according to the present invention is preferably a suspension polymerization method in order to adjust the THF-insoluble content, but in order to adjust the molecular weight distribution, it is basically a method of synthesizing two or more types of polymers. preferable.

That is, a method in which a first polymer soluble in THF and soluble in a polymerization monomer is dissolved in a polymerization monomer containing a crosslinking monomer, and the monomer is polymerized to obtain a resin composition containing a crosslinking region component. It is.

In this case, since the former and latter polymers are uniformly mixed, when the resin is applied to the toner, the durability of the toner
It is possible to improve fixing and offset properties without impairing blocking resistance and the like.

The first polymer soluble in THF is preferably subjected to solution polymerization or ionic polymerization, and the second polymer for producing a component insoluble in THF is prepared under conditions that dissolve the first polymer. It is preferable to synthesize by suspension polymerization or bulk polymerization in the presence of a crosslinking monomer. The first polymer is preferably used in an amount of 10 to 120 (preferably 20 to 100 parts by weight) parts by weight based on 100 parts by weight of the polymerizable monomer for producing the second polymer.

In addition to the above-mentioned binder resin component, the toner using the resin of the present invention may contain the following compounds in a proportion smaller than the content of the binder resin component, within a range that does not adversely affect the effects of the present invention. You can.

For example, silicone resin, polyester, polyurethane, polyamide, epoxy resin, polyvinyl butyral,
Rosin, modified rosin, terpene resin, phenolic resin,
Aliphatic or alicyclic hydrocarbon resins such as low molecular weight polyethylene or low molecular weight polypropylene, aromatic petroleum resins,
These include chlorinated paraffin and paraffin wax.

As the colorant contained in the toner according to the present invention, generally known dyes and pigments can be used. Examples of such dyes and pigments include Rikiichi Bon Black, Nigrosine Dye, Lamp Black, Sudan Black SM, First Yellow G, Benzidine Yellow, Pigment Yellow, India First Orange, Irgazine Red,
Paranitroaniline Red, Toluidine Red, Carmine FB, Permanent Bordeaux FRR, Pigment Orange R, Lysol Red 2G, Lake Red C1 Roguemin FB, Rhodamine B Lake, Methyl.
Violet B Lake, Phthalocyanine Blue Pigment Blue, Prilliant Green B, Phthalocyanine Green, Oil Yellow GG, Pomelo Fast Yellow CGG, Kayaset Y 963, Kayaset Y
G, Sumiplast Elo 10G, Pomelo First Orange RR, Oil Scarlet, Sumiblast Orange G, Orazole Brown B, Pomelo First Scarlet CG, Eisensviron Red BEH.
Oil pink OP etc. can be applied. These colorants are
It is generally used to obtain a capsule toner for a two-component developer, and is preferably added in a proportion of 5 to 20% to the core binder.

When the toner according to the present invention is used as a magnetic toner, the magnetic fine particles contained include metals made of ferromagnetic elements such as iron, cobalt, and nickel, including ferrite and magnetite, or alloys or compounds containing these, or Alloys that do not contain strongly magnetic elements but become ferromagnetic through appropriate heat treatment, such as Heusler alloys containing manganese and copper such as manganese-copper-aluminum or manganese-copper-tin. metal alloys, or chromium dioxide, among others. The content ratio of the fine powder of these magnetic substances can be 30 to 150 parts by weight, preferably 40 to 100 parts by weight, based on 100 parts by weight of the binder resin. It is also possible to use the magnetic fine particles as a black or brown pigment.

The charge control agent contained in the toner according to the present invention includes:
A conventionally known charge control agent is selected. Specific examples of positive charge control agents include nigrosine, azine dyes containing an alkyl group having 2 to 16 carbon atoms (Japanese Patent Publication No. 1627/1983), and basic dyes (for example, C.I. Basic Ye).
low 2 (C.L41000), C. I. Ba
sicYellow 3,C. I. Basic Re
d 1 (C.I.45160), C. I. Basi
c Red 9 (C.I.42500), (:.I.
BasicViolet 1 (C.I.42535
). C. I. Basic Violet 3 (C.I.
．． 42555), C. I. Basic Viol
et 10 (C.I.45170). C. I. Ba
sic Violet 14 (C.I. 42510
) C. I. Basic Blue l (C.I.4
2025), C. I. BasicBlue 3 (C
．． I. 51005). C. I. Basic Blue
e 5 (C.I.42140), C. I. Bas
ic Blue 7 (C.I.42595), C.I.
I. Basic Blue 9 (C.I.52015
), C. I. Basic Blue 24 (C.I.
52030). C. I. Basic Blue 2
5 (C.I.52025). C. L Basic Bl
ue 26 (C.I.44025), C. I. B
asicGreen Green 1 (C.I.42
040), C. I. Basic Green4 (C
．． I. 42000), lake pigments of these basic dyes (lake-forming agents include phosphotungstic acid, phosphomolybdic acid, phosphotungsten molybdic acid, tannic acid, lauric acid, gallic acid, ferricyanide, ferrocyanide, etc.)C ．． Ding. Sovent Black
k3 (C.I.26150). Hansa Yellow G
(C.r.11680), C.R. I. Mordlan
t Black 11,C. I. Pigment B
Lack I etc.

Alternatively, polyamide resins such as quaternary ammonium salts such as benzolmethyl-hexadecyl ammonium chloride and desyl-trimethyl ammonium chloride, vinyl polymers containing amino groups, condensed polymers containing amino groups, and the like, preferably nigrosine. , quaternary ammonium salts, triphenylmethane-based nitrogen-containing compounds, and polyamides.

Further, as a specific example of the negative charge control agent, Japanese Patent Publication No. 41-20
Metal complexes of monoazo dyes described in No. 153, No. 42-27596, No. 44-6397, and No. 45-26478, as well as nitroamic acid and its salts described in JP-A-50-133338. Or C. I
, dyes and pigments such as 14645, Zn of salicylic acid, naphthoic acid, guicarboxylic acid, etc. described in Japanese Patent Publication No. 42752/1983, Japanese Patent Publication No. 41508/1988, Japanese Patent Publication No. 7384/1984, and No. 7311t5/1989, etc. Aj
), metal complexes such as Go, Cr, and Fe, sulfonated copper phthalocyanine pigments, nitro groups, styrene oligomers into which halogens have been introduced, and chlorinated paraffins. In particular, from the viewpoint of dispersibility, metal complexes of monoazo dyes, metal complexes of salicylic acid, alkylsalicylic acid, naphthoic acid, and guicarboxylic acid are preferred. The amount of these charge control agents added is determined to maintain good triboelectric charging properties as described above, while minimizing adverse effects such as a decrease in developing power and a decrease in environmental stability due to contamination of the surface of the developing sleeve by the charge control agents. Therefore, the amount added is preferably 0.1 to 3 parts by weight per 100 parts by weight of the binder resin.

An ethylene olefin polymer may be used as a fixing aid in the toner of the present invention together with a binder resin.

Examples of the ethylene-based olefin monopolymer or ethylene-based olefin copolymer used here include polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, polyethylene There are ionomers having a skeleton, and the above-mentioned copolymers preferably contain 50 mol% or more (more preferably 60 mol% or more) of olefin monomers.

Next, an electrophotographic method using a developer using a resin according to the present invention will be explained.

The process of developing the electrical latent image with toner includes the aforementioned magnetic brush method, cascade development method, powder cloud method, and conductive magnetic toner described in U.S. Pat. No. 3,909,258. A method using JP-A-53-3113
There is a method using a high-resistance magnetic toner as described in Japanese Patent No. 6. The toner using the resin according to the present invention is also suitable for a developing method using a so-called one-component developer containing magnetic particles. In the step of transferring the developed image to the transfer member, an electrostatic transfer method such as a corona transfer method or a bias application method to the abutting transfer member is used.

Incidentally, in recent years, methods such as charging and/or transfer and/or static elimination that utilize corona discharge from a member that does not contact the photoreceptor onto the photoreceptor are accompanied by ozone generation, so methods that use corona discharge from a member that does not come into contact with the photoreceptor are accompanied by ozone generation. A method of applying bias through the member is attracting attention.

With the transition to such systems, there is a possibility that the activated carbon filters often attached to conventional copiers and printers will be removed;
The toner of the present invention exhibits remarkable effects.

Furthermore, in the toner using the binder resin of the present invention, a blade cleaning method, a fur brush cleaning method, etc. are applied to the step of removing residual toner on the photosensitive layer or insulating layer, but the blade cleaning method is particularly applicable. Are suitable.

The powder image on the transferred member needs to be fixed on the member, and methods for this purpose include heat fixing, solvent fixing, flash fixing, and laminate fixing. Suitable for roller fixing method.

[Examples] Hereinafter, the present invention will be specifically explained using Examples, but these are not intended to limit the present invention in any way.

Incidentally, all parts and percentages described in the examples indicate parts by weight and percentages by weight.

200 parts of cumene was placed in a foreskin-separated reactor, and the temperature was raised to reflux temperature. To this was added 100 parts of styrene monomer and
- A mixture of 8 parts of butyl peroxide was added dropwise over 4 hours under cumene reflux. Furthermore, under reflux of cumene (146℃~
Polymerization was completed at 156°C) and cumene was removed. The obtained boristyrene was dissolved in T}IF and Mw = 3700,
Mw/Mn = 2.64,' The molecular weight at which the main peak of GPC was located was 3500, and Tg = 57°C.

30 parts of the above boristyrene is dissolved in the following monomer mixture,
A mixed solution was prepared.

(Left below) Add 0 partially saponified polyvinyl alcohol to the above mixed solution.
170 parts of water in which 1 part was dissolved was added to prepare a suspension solution.

15 parts of water was added and sufficient nitrogen was introduced through a nitrogen introduction tube. In this state, the above dispersion liquid was added to the reactor, and a suspension polymerization reaction was carried out at a reaction temperature of 70 to 95°C for 9 hours. After the reaction was completed, the mixture was dehydrated and dried to obtain a composition of polystyrene and styrene-n-butyl acrylate copolymer. In this composition, the THE-insoluble content and the THF-soluble content were uniformly mixed, and the polystyrene and the styrene-n-butyl acrylate copolymer were uniformly mixed. The THF-insoluble content of the resulting resin composition (using resin composition powder of 24 mesh pass and 60 mesh on) was 25 vvt%. In addition, when the molecular weight distribution of THF-soluble components was measured, it was found to be 0.4
It had a peak at the position of 10,000 and 34,000, Mn = 06,550,000, Mw = 130,000, Mw/Mn = 24, and the molecular weight of 10,000 or less was 25 wt%. Furthermore, the Tg of the resin is 58
It was °C.

200 parts of cumene was placed in a Nenko 3-Kudan reactor and the humidity was raised to reflux temperature. The following mixture was added dropwise to the cumene over 4 hours under reflux.

Further, the polymerization was completed under cumene reflux (146 to 156°C), and cumene was removed. The obtained styrene-α-methylstyrene copolymer had Mw=4500, Mw/Mn=2
．． 8. Molecule i 4400 in GPC chart
The main beak was located at , and Tg was 63°C.

30 parts of the above styrene-α-methylstyrene copolymer was dissolved in the following monomer mixture to form a mixed solution.

Add 0% of the partially saponified polyvinyl alcohol to the above mixed solution.
170 parts of water in which 1 part was dissolved was added to form a suspension dispersion. After adding 15 parts of water and flushing nitrogen sufficiently in the same manner as in Synthesis Example 1, the above dispersion was added to the reactor, and the reaction temperature was 70 to 9.
The reaction was carried out at 5°C for 9 hours. After the reaction is complete, dehydrate the
After drying, a composition of a styrene-α-methylstyrene copolymer and a styrene-2-ethylhexyl acrylate copolymer was obtained.

The THF-insoluble content of this composition was 32 wt%.

In addition, when the molecular weight distribution of the IF-soluble component was measured, there were peaks at molecular weights of 0.5 million and 4.2 million, and Mn = 0.
．． 620,000, Mw=130,000, 'Mw/Mn = 21,
The molecular weight of 10,000 or less was 20 wt%. Also, the Tg of the resin
was 58°C.

200 parts of cumene was placed in a metal reactor and heated to reflux temperature. The following mixture was heated under cumene reflux for 4 hours, and the polymerization was completed under cumene reflux (146-156°C) to remove cumene. The obtained styrene-methacrylate copolymer had Mw = 3900, Mw/Mn = 2.6, a main peak at a molecular weight of 4100, and Tg = 60.
It was ℃.

40 parts of the above styrene-methyl methacrylate copolymer was dissolved in the following monomer mixture to prepare a mixed solution.

(Left below) Add polyvinyl alcohol partially saponified CI to the above mixed solution.
．． 170 parts of water in which 1 part was dissolved was added to form a suspension dispersion.

After adding 15 parts of water and thoroughly passing nitrogen in the same manner as in Synthesis Example 1, the above dispersion was added to the reactor, and the reaction temperature was 70 to 9.
The reaction was carried out at 5°C for 9 hours. After the reaction was completed, the mixture was separated in a furnace, dehydrated, and dried to obtain a composition of styrene-methyl methacrylate copolymer and styrene-n-butyl methacrylate copolymer.

The THF-insoluble content of this composition was 35 wt%.

In addition, the molecular weight distribution of THF-soluble components was measured and was found to be 0.4.
It has a peak at 0.43 million, Mn=0.59 million, Mw
= 92,000, Mw/Mn = 16, and the molecular weight of 10,000 or less was 32 wt%. Furthermore, the Tg of the resin was 60°C.

Add 0.1% of partially saponified polyvinyl alcohol to the above mixture.
170 parts of water was added to prepare a suspension and dispersion. water 1
After 5 parts of the dispersion was added to the reactor and nitrogen was sufficiently passed in the same manner as in Synthesis Example 1, the above dispersion was added to the reactor and the reaction temperature was adjusted to 70 to 95°C.
The mixture was allowed to react for 9 hours. After the reaction was completed, the mixture was separated in a furnace, dehydrated, and dried to obtain a styrene-n-butyl acrylate copolymer composition.

The THF-insoluble content of this composition was 44 wt%.

In addition, when the molecular weight distribution of THF-soluble components was measured, there was a peak at the molecular weight position of 2,000,000, Mn = 0,800, Mw
= 28,000, Mw/Mn = 3.5, and the molecular weight of 10,000 or less was 21 wt%. Furthermore, the Tg of the resin is 56°C
Met.

Comparison j-L Bonito 1 200 parts of cumene was placed in a reactor and heated to reflux temperature. To this was added 100 parts of styrene monomer and
A mixture of 8 parts of butyl peroxide was added to 4 parts of cumene under reflux.
It dripped over time. Furthermore, under reflux of cumene (146℃~1
Polymerization was completed at 56°C) and cumene was removed. The obtained boristyrene was dissolved in THF and Mw = 370 (1, M
w/Mn=2. 64, the molecular weight at the main beak of GPC was 3500, and Tg = 57°C.

30 parts of the above boristyrene is dissolved in the following monomer mixture,
A mixed solution was prepared.

Add 0% of the partially saponified polyvinyl alcohol to the above mixed solution.
170 parts of water in which 1 part was dissolved was added to form a suspension dispersion.

15 parts of water was added to the reactor without passing nitrogen through the dispersion, and suspension polymerization reaction was carried out at a reaction temperature of 70 to 95°C for 9 hours. After the reaction was completed, the mixture was dehydrated and dried to obtain a composition of polystyrene and styrene-n-butyl acrylate copolymer.

200 parts of cumene was placed in a reactor and heated to reflux temperature. To this was added 100 parts of styrene monomer and
A mixture of 8 parts of butyl peroxide was added to 4 parts of cumene under reflux.
It dripped over time. Further, under reflux of cumene (146℃~1
Polymerization was completed at 56°C) and cumene was removed. The obtained boristyrene was dissolved in THF and Mw = 3700, Mw
/Mn = 2.64, the molecular weight at the main beak of GPC was 3500, and Tg = 57°C.

30 parts of the above boristyrene is dissolved in the following monomer mixture,
A mixed solution was prepared.

Add 0% of the partially saponified polyvinyl alcohol to the above mixed solution.
170 parts of water in which 1 part was dissolved was added to form a suspension dispersion.

The above dispersion was added to a reactor containing 15 parts of water and the atmosphere was replaced with nitrogen, and a suspension polymerization reaction was carried out at a reaction temperature of 70 to 95°C for 6 hours. After the reaction was completed, the mixture was dehydrated and dried to obtain a composition of polystyrene and styrene-n-butyl acrylate copolymer.

After mixing the above raw materials, they were hot-melted and kneaded using an extruder at 120° C., and after cooling, they were crushed and classified to obtain a negatively charged magnetic toner having a volume average particle diameter of 11 μm. To 100 parts of negatively charged magnetic toner, 0.4% of negatively charged colloidal silica was externally added to make a magnetic toner having silica on the surface of the toner particles, and in order to prevent ozone generation, a corona charger was used as shown in Figure 1. The sample was converted into a contact charging roller and put into a modified Canon laser beam printer LBP-SX from which the ozone filter had been removed, and continuous printing was performed on the entire surface in solid black, and the odor generated was observed.

Odor evaluation was carried out by installing the above printer in the center of a small room approximately 3 meters square, making copies, and randomly selecting lO
The test was conducted in a so-called panel test format, in which a person smells the odor while changing positions little by little and judges whether it is .

As a result, very good results were obtained, and it was determined that the toner had no problem with odor (see Table 1).

Incidentally, as a result of analyzing the toner, the amount of benzaldehyde that should be generated due to oxidation of styrene monomer was 0. 002
It was below.

A magnetic toner was prepared and evaluated in the same manner as in Example 1 except that the resin used in Synthesis Example 2 was used, and similarly good results were obtained.

Further, the benzaldehyde content in the toner is 0. 003
%Met.

A magnetic toner was prepared and evaluated in the same manner as in Example 1, except that the resin used in Royu Odori was replaced with the resin of Synthesis Example 3 and the extruder's hot melt mixing temperature was 100°C. Many people noticed an odor, but it was determined that there was no particular problem.

The amount of benzaldehyde in the toner at that time was 0. 005
%Met.

A magnetic toner was prepared and evaluated in the same manner as in Example 1 except that the resin used was changed to the resin of Synthesis Example 4.
Although the obtained solid black image was within a practical range, the fixing performance was slightly inferior, but similarly good results were obtained in terms of odor.

Note that the amount of benzaldehyde in the developer was 0.003%.

When the same procedure as in Example 1 was carried out except that the corona charger of the printer LBP-SX was left as is and only the ozone filter was removed, almost no aldehyde odor was noticed, but an ozone odor was detected. There were many people. It was determined that it is usable for practical use.

When the same procedure as in Example 1 was carried out except that the resin used in Comparative Synthesis Example 1 was replaced, many people were concerned about the odor.
It was judged to be impractical.

The amount of benzaldehyde in the developer at that time was 0. 009
%Met.

A magnetic toner was prepared in the same manner as in Example 1 except that the resin used was changed to the resin of Comparative Synthesis Example 2, and when evaluated, it was determined that it was not practical as in Comparative Example 1. .

At that time, the amount of benzaldehyde in the toner was 0. 00
It was 7%.

The results of the odor panel tests conducted in Examples are summarized below.

[Effects of the Invention] With the wide spread of electrophotography, there is a demand for toners with good odor resistance during hot melt fixing.In order to meet this demand, the present inventors have developed It was discovered that the amount of oxides of polymerizable monomers remaining in the toner, especially the amount of aldehydes, has a large influence, and in order to achieve the reduction, the amount of dissolved oxygen in water during suspension polymerization of the binder resin used in toner is particularly important. We found that it is effective to control the

The toner synthesized through these measures has an extremely low odor and is used for copying with low ozone generation, eliminating charging, neutralization, transfer, etc. using corona discharge from a member that does not contact the photoreceptor onto the photoreceptor. This made it possible to supply toner to machines and printers.

[Brief explanation of drawings]

FIG. 1 shows a charging roller of a modified laser beam printer used in Examples and Comparative Examples. 1: Charging roller made of conductive rubber 2: Photosensitive drum 3: High voltage power supply for applying charge Figure 1

Claims (3)

[Claims] (1) A toner for developing electrostatic images containing at least a binder resin and a colorant, characterized in that the content of aldehyde monomers is 0.005% by weight or less. . (2) In a method for producing an electrostatic image developing toner containing at least a binder resin and a colorant, the binder resin has a content of the colorant and aldehyde monomers of 0.01% by weight or less. A method for producing a toner for developing an electrostatic image, the method comprising: melting and kneading while heating, cooling, and then pulverizing. (3) The toner for developing an electrostatic image according to claim 2, wherein the binder resin is a styrene resin containing 0.01% by weight or less of aldehyde monomers produced by a suspension polymerization method. Production method.