JPS6093457A - Toner for developing electrostatic latent image - Google Patents

Abstract

PURPOSE:To provide a toner which has substantial non-offsettability and can widen a fixable temp. region and to form stably a good visible image by incorporating the 1st wax consisting of polyolefin and the 2nd wax consisting of polyolefin modified by using an alpha-methylene aliphat. monocarboxylic acid ester monomer. CONSTITUTION:The 1st wax consisting of polyolefin and the 2nd wax consisting of the polyolefin modified by the polymer obtd. by block copolymerization of an alpha-methylene aliphat. monocarboxylic acid ester monomer and polyolefin or by the acrylate monomer obtd. by using the polyolefin as the trunk of the chain and graft-copolymerizing an acrylate monomer therewith are incorporated into the particulate material of a binder resin. The ratio of the total of the 1st and 2nd waxes to be incorporated is made within a 1-40wt% range by the weight of the binder resin. The ratio between the 1st wax and the 2nd wax is made 0.5-10 parts by weight the latter with respect to 1 part the former. The toner which is adequate for high speed fixing by a heat roller fixing device is thus obtd.

Description

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

[Techniques for using rice]

Electrostatic charge image 3j1. The imaging step is a step in which charged fine particles are attracted by electrostatic attraction and deposited on the surface of an electrostatic image support, thereby visualizing an electrostatic image.

The specific method for carrying out such a developing process is as follows:
It consists of a wet development method using a liquid developer in which pigments or dyes are finely dispersed in an insulating organic liquid, and a toner in which a coloring agent such as carbon black is dispersed in a binder made of natural or synthetic resin. There are dry developing methods that use a powder developer, such as a cascade method, a bristle brush method, a magnetic push method, an impression method, and a powder cloud method.

The image visualized in the developing step may be fixed on a support, but usually it is transferred to another support such as transfer paper and then fixed. In this way, the toner is not only subjected to the development process, but also to the subsequent processes, that is, the transfer process and the fixing process, so the toner has not only good developability but also the following processes: It is claimed to have good transferability and fixability. Among these, the conditions related to fixing properties are the most severe, and many studies and results have been published in the past on improving the fixing properties of this toner.

It is generally advantageous to use a heat fixing method to fix the toner image formed in the developing process or the image to which this is transferred.This heat fixing method includes a non-contact heat fixing method such as open fixing, and a heat roller There is a contact heating fixing method such as fixing. The contact heat fixing method is commercially superior in thermal efficiency and is particularly capable of high-speed fixing, making it suitable for fixing in high-speed copying machines. 1. Since a relatively low-temperature heat source can be used, this method requires less power consumption, making it possible to downsize the copying machine and save energy. Further, even if paper accumulates in the fixing device, there is no risk of fire, and this is also advantageous.

Although the contact heat fixing method is preferable in various respects as described above, this method has a serious problem of occurrence of an offset phenomenon. This is a phenomenon in which a portion of the toner constituting the image is transferred to the surface of the heat roller during fixing, and this is transferred again to the transfer paper or the like that is fed next, staining the image. In order to prevent this offset phenomenon, various proposals have been made and some have been put into practical use. One is to perform fixing while applying a release oil such as silicone oil to the surface of a heated roller, and the other is to provide the toner itself with anti-offset performance. The latter method is superior in that the structure of the fixing device is simple because a silicone oil application mechanism or the like is not required, and maintenance such as replenishment of silicone/oil is not required.

The offset phenomenon occurs when the temperature of the heat roller increases, and therefore, the lowest temperature at which the offset phenomenon occurs (hereinafter referred to as "offset occurrence temperature"), the higher the temperature, the better the non-offset properties of the toner. However, in order for the toner to be fixed, it must be heated to a temperature above its softening point. Therefore, in an actual heat roller fixing device, the temperature of the heat roller is set at a temperature higher than the softening point of the toner. The temperature is set to a specific temperature within the fixable temperature range that is higher than the offset temperature and lower than the offset generation temperature.

However, in reality, it is not possible to maintain the temperature of the heat roller completely uniformly at the set temperature, and there are other factors that must be taken into consideration regarding the temperature, so the temperature range that can be fixed is wide and the height is high. A toner that does not reduce the advantages of the contact heat fixing method is desirable.

Generally, in order to raise the offset occurrence temperature of a toner, it is effective to use a binder resin containing a high molecular weight component. Since the resin has a high softening point, the minimum temperature required for one fixation of the toner (hereinafter referred to as "minimum fixing temperature") becomes high, and the original point of the contact heat fixing method is lost. .

It is naturally desirable that this minimum fixing temperature be low, and in order to achieve the formation of visible images on both sides of a single sheet of transfer paper, which has recently become a high demand, the toner used for development must be It is necessary that the material can be fixed at a low temperature.

In view of the above-mentioned background, a means has been developed for lowering the minimum fixing temperature by incorporating a low softening point wax made of a release agent such as polypropylene wax or polyethylene wax into toner particles. However, in this method, since the fluidity of the powdered toner is reduced, the developability and transferability are reduced, a good visible image cannot be formed, and there is a tendency for the toner to become cohesive. Moreover, in order to obtain the effect of adding wax, the content ratio of the wax must be increased considerably, and as a result, the wax component adheres to the developing sleeve or image support to form a film. However, there are drawbacks that impair its functionality.

In order to improve the fluidity of toner, it is effective to add a fluidity improver made of fine hydrophobic silica powder to toner powder. In order to obtain Ni, it is necessary to add hydrophobic silica fine powder,
Surprisingly, thanks to the extremely hard hydrophobic silica powder! The second side of the electrostatic image support becomes damaged, which is a serious problem when the support is a photoconductive photoreceptor, and when surface cleaning of the electrostatic image support is performed with a rubber blade. In addition, the wear of the blade becomes severe,
In image forming apparatuses that have a recycling system in which toner that has been subjected to VC development but has not participated in the formation of toner images is returned to the developing device for reuse, fine particles of hydrophobic silica are embedded in the surface of the toner particles. As a result, the fluidity of the toner decreases, resulting in a visible image of low quality.

[Purpose of the invention]

The present invention has been made based on the above-mentioned circumstances, and its objects are to have sufficient non-offset properties, a low minimum fixing temperature, a wide fixable temperature range, and a fluid and non-agglomerating temperature range. It is an object of the present invention to provide a toner for developing a silent image, which has excellent properties and can consistently form good visible images.

[Structure of the invention]

The present invention is characterized by containing a first wax made from polyolefin and a second wax made from a polyolefin self- or graft-copolymerized with block group type or graft copolymerization with an α-methylene aliphatic monocarboxylic acid ester monomer. At the point.

The present invention will be specifically explained below.

In the present invention, i
Along with colorants, charge control agents and other necessary toner components,
A first wax consisting of a polyolefin (hereinafter referred to as "rice-made wax") and an a-methylene aliphatic monocarphonic acid ester monomer (hereinafter referred to as "acrylate monomer").
”. ) and a polyolefin, or a polymer obtained by craft copolymerizing an acrylate monomer with a polyolefin as a chain trunk, that is, a polyolefin modified with an acrylate monomer (hereinafter referred to as a "modified polyolefin") (hereinafter referred to as "qualitative wax") is contained to form a toner for developing an electrostatic image.

In the above, the amount of inedible wax and modified wax to be used is such that the total content ratio of both is within the range of 1 to 40% by weight, preferably 1 to 20% by weight based on the binder resin.
Within the range of weight%. If this proportion is less than 1% by weight,
The effect of the wax as a release agent is not exhibited, so the non-onset property of the toner is not improved;
If it exceeds this range, the fluidity of the toner will decrease, resulting in poor developability and transferability, making it impossible to form a good visible image, and the wax will adhere to the developing sleeve or electrostatic image support. and forms a film that inhibits its function.

Also, the ratio of unmodified wax to modified wax is 1
In the warehouse, the ratio of the latter to 1 part of the former is 0.5 to 1 part, preferably 0.5 to 5 parts. When the latter ratio is too small, the fluidity of the toner is insufficient, and on the other hand, when the former ratio is unfavorable, the offset generation temperature becomes low.

As the binder resin, those normally used for this purpose can be used, but for practical purposes, styrene resin, acrylic resin, styrene-acrylic copolymer resin, other vinyl resins, polyester resins, Others are preferred.

One particularly preferred binder resin is a polymer or copolymer of styrene monomers, that is, a polymer or copolymer of one or more styrene monomers, or a styrene monomer. and other vinyl monomers, and is a styrene resin having a ratio Mw/Mn of weight average molecular weight (Mw) to number average molecular weight (Mn) of 3.5 or more.

Specific examples of the styrene monomer include styrene, 0-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p- n-Butylstyrene, p-tert-butylstyrene% p-'-hexylstyrene% p-"'-octylstyrene, p-
n-nonylstyrene, p-n-decylstyrene, p-n
-dodecylstyrene, p-methkinstyrene, p-phenylstyrene, p-chlorostyrene, 3+4-')chlorostyrene, and the like.

As the copolymer of a styrene monomer and a vinyl monomer, a styrene-butadiene copolymer or a styrene-acrylic copolymer is particularly preferable. Examples of the acrylic monomer for the acrylic component include methyl acrylate, ethyl acrylate, n-butyl acrylate, inbutyl acrylate, globil acrylate, n-octyl acrylate, dodecyl acrylate, and lauryl acrylate. , 2-ethylhexyl acrylate, stearyl acrylate, 2-chloroethyl acrylate, phenyl acrylate, a-chloromethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate , inbutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, 2-ethylhexyl methacrylate, stearyl methacrylate, phenyl methacrylate, dimethylaminoethyl methacrylate,
α-methylene aliphatic monocarboxylic acid esters such as diethylaminoethyl methacrylate; acrylonitrile;
Examples include methacrylonitrile, acrylic acid or methacrylic acid derivatives such as acrylamide, and others. These monomers can be used alone or in combination.

The above styrene resin has an Mw/Mn value of 3.5, but it is preferable that the Mw/Mn is 5 or more, and the molecular weight is about 2000 to 30000 in Mn.
Those having a value of 1 are particularly attractive. Note that the values of MW%Mn and Mw/Mn can be measured by various methods, and there are slight variations depending on the measurement method. Therefore, in the present invention, Mw, Mn and Mw/M
The value of n measured by the following measurement method is defined as Ω.

That is, all of these values are values measured by gel permeation chromatography under the conditions described below. The solvent (tetrehydrofuran) was flowed at a flow rate of 1/min at a temperature of 25°C, and the concentration was 0.4 t/min.
dt of tetrahydrofuran sample solution as sample weight 8
■Inject and measure. When measuring the molecular weight of a sample, the molecular weight distribution of the sample is determined using several types of monodisperse polystyrene standard samples. Select measurement conditions that fall within a range in which the logarithm of the molecular weight and the count number of the calculated calibration curve form a straight line. In addition, the reliability of this measurement was determined using the NB8706 boristyrene standard sample (
MW=28.8X1(!', Mn=13.7xl O
'JMw/Mn = 2.11) Mw/Mn is 2.1
Confirm that it is 1±0.10.

Furthermore, the styrenic resins mentioned above differ depending on the monomer S@ contained as a constituent component, but in general, those with a softening point of about 100 to 170°C according to the ring and ball method are particularly effective. Furthermore, those having a glass transition point of 40° C. or higher are particularly effective. That is, the softening point is 10
If the temperature is below 0°C, over-pulverization is likely to occur, and the light guide plate is likely to be contaminated by toner filming.

Further, if the softening point exceeds 170° C., it is hard and difficult to crush, and furthermore, a large amount of heat is required during fixing, resulting in poor fixing efficiency. On the other hand, if the glass transition point is 40°C or lower, the storage conditions for the toner are usually 40°C or lower.
Since the temperature is below °C, agglomeration is likely to occur due to the cold flow phenomenon.

In addition, the glass transition point of styrene resin is generally Mw7M.
As the value of n increases, it tends to have a wider range and is difficult to show a specific value, so it may be difficult to measure the glass transition point of a resin with a large value of M4w/Mn.

The styrene resin can be synthesized by the following method. Using the general neck method, Mw/Mn is 1.
A resin of 5 to 3.0 is obtained. However, in order to obtain a resin having Mw/'h/in of 35 or more used in the invention, the following method is used. That is, one method is to carry out polymerization by continuously or intermittently changing the polymerization temperature. Another method is to polymerize a divinyl compound and a trivinyl compound in combination. Yet another method is to sequentially add several types of monomers with different initiator concentrations and chain transfer agents.
There is a method of IL polymerization. In particular, by mixing a relatively low molecular weight resin with a relatively low molecular weight resin, MW/
A resin with a high Mn content can be obtained. These methods can be carried out by bulk type method, solution polymerization method, suspension polymerization method, emulsion polymerization method, etc. However, the suspension polymerization method is most preferable due to the ease of handling of the resin obtained and the reduction in manufacturing costs. In addition, one method for increasing M%v7Mn is to dissolve several types of resins with different molecular weights in a solvent and remove the solvent by drying under reduced pressure or spray drying, or to melt them by heating and blend them. O
Another example of a preferred binder resin in the present invention 8Avc is a polyester resin, which is obtained by polycondensation of an alcohol and a carboxylic acid.

Examples of the alcohol used here include ethylene glycol, diethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, and 1°4-butynediol. Diols such as 1,4-bis(hydroxymethyl)cyclohexane, and bhisphenol A, hydrogenated bisphenol A1
Examples include etherified bisphenols such as poly(diethyleneated bisphenol A1 polyoxypropylene) and diphenol A, and other dihydric alcohol monomers.

Examples of carboxylic acids include maleic acid, 7-maric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, 7-talic acid, inphthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, cepatic acid, Mention may be made of malonic acid, anhydrides of these acids, dimers of lower alkyl esters and lyluic acid, and other divalent organic acid monomers.

In the present invention 8I4, the polyester resin is
It is also suitable to use not only a polymer made only of the above difunctional monomers but also a polymer containing a component made of trifunctional or higher polyfunctional monomers. Examples of such polyfunctional monomers, such as trivalent or higher polyhydric alcohol monomers, include sorbitol, 1°2.3.6-hexanetetrol, 1.
, 4-sorbitan, pentaerythritol, dipentaerythritol, tripentaerythritol, sucrose, 1゜2.4-butanetriol, 2, 5-pentanetriol, glycerol, 2-methylpropanetriol, 2-methyl-1 , 2't 4-butanetriol, trimethylolethane, trimethylolpropane,
(2), 3,5-trihydroxymethylbenzene, and others.

In addition, as a trivalent or higher polyvalent carboxylic acid monomer, for example, 1
, 2.4-benzenetricarboxylic acid, 1゜2.5-benzenetricarboxylic acid, 1,2.4-cyclohexanetricarboxylic acid, 2,5.7-naphthalenetricarboxylic acid,
1,2.4-naphthalenetricarboxylic acid, 1,2.4-
Butanetricarboxylic acid, 1,2,5-hexanetricarboxylic acid, 1,3-dicarboxyl-2-methyl-2-methylenecarboxypropane, teto2(methylenedi/carboxyl)methane, 1. ．． Components consisting of trifunctional or higher functional monomers such as 0 or higher, which can include 2,7.8-octane tetracarboxylic acid, Empol trimer acid, their acid anhydrides, etc., are polymers. 30 in each of the alcohol component or acid component as a structural unit in
It is desirable that it be contained in a proportion of ~80 mol.

The polyester resin used in the present invention preferably has a chloroform-insoluble content of 5 weight or more. The chloroform-insoluble content herein refers to the content that does not permeate through P paper when a sample is dissolved in chloroform, and can be determined as follows.

The resin sample was finely pulverized, 5.00 tons of sample powder that passed through a 40-meter sieve was collected, and filter aid Radiolite (φ7
00) 5.0Of into a container with a capacity of f150-, inject chloroform 1002 into this container, place it on a ball mill stand, and rotate it for 5 hours or more to fully dissolve the sample in chloroform. On the other hand, place a piece of paper (diameter 2) in the pressurized filter, and place a piece of paper with a diameter of 5.90
After uniformly precoating the 2nd layer of t and adding a small amount of chloroform to bring the ν paper into close contact with the filter, the contents of the container are poured into the filter. Wash the container thoroughly with 100% chloroform and pour it into a container.
Make sure that no deposits remain on the walls of the container. After that, close the top lid of the Okisudan and perform filtration. Filtration is 4 kg
After the outflow of chloroform has stopped, 100% of chloroform is newly added to wash the residue on the paper, and pressure filtration is performed again.

After completing the above operations, the p paper and the residue on it [
2 Place all of the Diolite on aluminum foil and place it in a vacuum dryer at a temperature of 80 to 100°C and a pressure of 100 mm.
It was dried under HH conditions for 10 hours, and the typical model it a b> of the dry solid product thus obtained was measured, and the chloroform insoluble content X(] (% in j!') was calculated using the following formula.

X (% by weight) In the case of polyester resins, the chloroform-insoluble content determined in this manner is a high molecular weight polymer component or a crosslinked polymer component.

Its molecular weight is believed to be approximately 200,000 or more.

The above-mentioned chloroform-insoluble components can be controlled to a considerable extent by appropriately selecting reaction conditions or by allowing an appropriate crosslinking agent to be present in the reaction system in the polymerization reaction of alcohol and carboxylic acid mentioned above. Can be formed in proportions.

In the present invention, the chloroporum insoluble content is 5% by weight.
Although the above polyester resin is bindarted, if a polyester resin containing less than 5% of the chloroform-insoluble content is used, the resulting toner will have a low offset temperature.

Another example of a binder resin preferably used in the present invention is a styrene-butadiene copolymer (hereinafter referred to as "8-B copolymer"). This S
-H copolymer is obtained by copolymerizing styrene monomer and butadiene, and the styrene monomers include styrene, 0-methylstyrene, nl-methylstyrene, p-methylstyrene. , a-methylstyrene, p-etherstyrene, 2,4-dimethylstyrene, p-n-
Examples include 7'tylstyrene, p-dodecylstyrene, p-methoxystyrene, p-phenylstyrene, p-chlorostyrene, and 7'-others.

Further, the S-B copolymer needs to contain a high molecular weight component having a molecular weight of 100,000 or more, and the content ratio thereof needs to be 10% by weight or more. When the content ratio of this high molecular weight component is less than 10 iD, the non-offset property of the binder resin itself disappears, so that the offset generation temperature becomes low.

In particular, a high molecular weight component with a molecular weight of 100,000 or more is
A range of 0 to 70111% is preferable because the offset generation temperature is high and the softening point is low.

Molecular weights in this specification refer to gel and molecular weight under the following conditions.
Permeation chromatography (Gel Permeation)
chromatography) method. RII Chi, “Waters 2
00 type GPC (Water's 200'Iyp
Using a "GPC) measuring can" (manufactured by Waters), a tetra/S idolefuran sample solution with a concentration of Q and 2 f/dt was poured at a temperature of 25 °C while the solvent (tetrahydrofuran) was flowing down at a flow rate of 1-min. A combination of 10'-10'-10'-10' is used as the column used for injecting and measuring 4q in sample weight.

The monodisperse polystyrene standard sample for setting the calibration curve was made of polystyrene manufactured by Pressure Chemical Co., Ltd. and had a molecular weight of 1,800,000.860,000.411.
000.160,000.98,200,51,000
．． 19.800.10,000.4,000 are used.

The molecular weight of tetrahydrofuran insoluble matter during measurement is 50.
The molecular weight in the present invention is 100.
It is a high molecular weight component of 000 or more.

The 8-B copolymer used in the present invention preferably has a styrene component (hereinafter referred to as "styrene component") content of 70 to 98% by weight, particularly 85 to 98% by weight. When an S-B copolymer with a styrene component content of less than 70% by weight is used, the force transition point of the binder oil and fat becomes low, and the resulting toner becomes cohesive and hardens during storage. Otherwise, it forms a lump inside the developing device. On the other hand, the styrene component is 98 times heavy! Lelbt-
When an S-B copolymer exceeding the above range is used, the softening point of the binder resin becomes high and the fixable temperature range becomes narrow.

The polyolefin constituting the unmodified wax contained in the toner of the present invention is a homopolymer type obtained from a single olefin monomer, or a copolymer type obtained by copolymerizing an olefin monomer with another monomer copolymerizable with it. It may be of any type.

The olefin monomers include, for example, ethylene, propylene, butycool, pentene-1, hexene-11, butene-1, octene-1, nonene-1, decene-1, and those having different positions of unsaturated bonds. isomers, as well as those having a branched chain consisting of an alkyl group, such as 3-methyl-1-butene, 3-methyl-2-pentene, 3-propyl-5-methyl-2-hexene, etc. and all other olefin mono-i-.

Other monomers that can be copolymerized with the olefin monomer include other olefin monomer #1, vinyl methyl ether, vinyl-〇-butyl ether, vinyl phenyl ether, etc., vinyl acetate, vinyl phenyl ether, etc. Vinyl esters such as butyrate, such as vinyl fluoride, vinylidene fluoride, tetrafluoroethylene, vinyl chloride, vinylitine chloride, haloolefins such as tetrachloroethylene, such as methyl acrylate, ethyl acrylate, n-butyl acrylate, methyl methacrylate, ethyl methacrylate,
Acrylic esters or methacrylic esters such as n-butyl methacrylate, stearyl methacrylate, N,N-dimethylaminoethyl methacrylate, t-butylaminoethyl methacrylate, for example acrylonitrile, N,N-dimethylacrylamide Examples include acrylic acid derivatives such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, etc., diethyl heptamalate, β-pinene, and various other organic acids.

Therefore, when the polyolefin component is a copolymer type, an olefin copolymer type obtained by copolymerizing at least two or more of the above-mentioned olefin monomers, such as ethylene-propylene copolymer, ethylene-propylene copolymer, etc. Copolymers such as butene copolymer, ethylene-pentene copolymer, propylene-butene copolymer, propylene-pentene copolymer, ethylene-3-methyl-1-butene copolymer, ethylene-propylene-butene copolymer, etc. or an olefin copolymer type obtained by copolymerizing at least one olefin monomer as described above and at least one monomer other than the olefin monomer as described above, such as an ethylene-vinyl acetate copolymer. , ethylene-vinyl methyl ether copolymer, ethylene-vinyl chloride copolymer, ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-acrylic acid copolymer, globylene-vinyl acetate) Copolymer, propylene-vinylethyl ether copolymer, globylene-ethyl acrylate copolymer, propylene-methacrylic acid copolymer, butene-vinylethyl ether copolymer, butene-methyl methacrylate copolymer, pentene -Vinyl acetate copolymer, hexene-vinyl butyrate copolymer, ethylene-propylene-vinyl acetate copolymer, ethylene-vinyl acetate-vinyl methyl ether copolymer, and other copolymer types.

When a copolymer type is used using a monomer other than an olefin monomer, it is preferable to use a copolymer type in which the proportion of the olefin portion of the olefin monomer in the polyolefin component is, for example, 50 mol or more.

This is because if the proportion of the olefin portion becomes small, the effect of improving the fixing properties of the toner will not be sufficiently exhibited.

The modified polyolefin constituting the modified wax is obtained by blocking or grafting a polyolefin component with a modifying component, and the polyolefin described above is used as the polyolefin component.Acrylate monomers are also used as the modifying component. Specific examples include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, propyl acrylate, n-octyl acrylate, dodecyl acrylate, lauryl acrylate, and 2-acrylate.
Ethylhexyl, stearyl acrylate, acrylic acid 2
-Chlorethyl, phenyl acrylate, a-p methyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic rR1
1-butyl, inbutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, lauryl methacrylate, metaafryl 1!2-ethylhexyl, lauryl methacrylate, phenyl methacrylate,
Examples include dimethylamine ethyl methacrylate, diethylaminoethyl methacrylate, and others.

A modified wax made of a modified polyolefin can be obtained by carrying out block copolymerization or graft copolymerization using the above-mentioned acrylate monomer and the above-mentioned polyolefin according to conventional methods and conditions. For example, for block copolymerization, it is possible to use a method using a living polymer, or a method in which a block copolymer is obtained by reacting radicals generated by mechanochemically splitting wax with a 7-acrylate monomer. In addition, for craft copolymerization, a method in which ozonized polyethylene is reacted with an acrylate monomer (polymer initiator method), a method in which grafting is performed using radiation, etc. can be used. Specific examples of preferred acrylate monomers as modifying components include methyl acrylate, methyl methacrylate, and n-butyl methacrylate.

Here, the proportion of the modified component in the modified polyolefin is 0.
．． It is preferably within the range of 1 to 50 weights, particularly 1 to 40 weights. If this ratio is too small, the fluidity of the toner will be significantly reduced, and if it is too large, the minimum fixing temperature of the toner will become high.

Further, it is desirable that such modified polyolefin itself has a low softening point, for example, JIS K2
531-1960, the softening point is 80 to 180°C, preferably 90 to 160°C.
It is desirable that the temperature is ℃.

The toner of the present invention is a granular material comprising the above-mentioned unmodified wax and modified wax dispersed in the above-mentioned binder resin together with a colorant, a magnetic substance, a property improver, and other necessary additives. Yes, the average particle size is usually 5~
Ruru in the range of 30 microns.

As a coloring agent, carbon black, nigrosine dye (
C, 1, Ya50415B), Aniline Blue ((:, 1
．． A304U5), Calco Oil Blue (C, 1, Yaa
zoec Blue 3), Chrome x +:+ -(
C,1,,A14090), Ultramarine Blue (C
, 1, A77103), DuPont Oil Red (C, 1
, Ja26105), quinoline yellow (C, 1, A4
7005), methylene blue chloride (C, 1, Todoroki 5)
2015), Phthalocyanine Blue (c, i.

474160), malachite green off-salate (C
, 1,442,000), lamp black (C, 1, A7
7266), Rose Bengal < c, 1. A4543
5), mixtures thereof, and others.

These colorants need to be contained in a sufficient proportion to form a visible image with sufficient concentration, and are usually about 1 to 2.0 parts by weight per 10.0 parts by weight of the binder resin. It is considered a percentage.

The magnetic material may be a metal or alloy that exhibits ferromagnetism such as ferrite, magnetite, iron, cobalt, or nickel, or a compound containing these elements, or a material that does not contain a ferromagnetic element but can be made by subjecting it to appropriate heat treatment. Mention may be made of alloys which become ferromagnetic, such as alloys of the type called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum, manganese-copper-tin, or chromium dioxide, among others. These magnetic substances are uniformly dispersed in the binder in the form of fine powder with an average particle size of 0.1 to 1 micron. The content i is 20-701 mjit parts, preferably 40-70 parts by weight, per 100 JLm.

Examples of the property improving agent include a charge control agent, an anti-offset agent, a lubricant for improving fluidity, and others.

The toner of the present invention is mixed with a carrier made of iron powder, glass beads, etc. to make a two-component developer, but when it contains a magnetic material, it can be used as is for developing electrostatic images as a one-component developer. .

〔Effect of the invention〕

Since the toner according to the present invention contains both an unmodified wax and a modified wax, the offset generation temperature is high, as will be clear from the description of the examples below.
Moreover, in spite of this, the minimum fixing temperature is low, making it suitable for high-speed fixing using a heat roller fixing device. In addition, the degree of decrease in fluidity due to the addition of wax is so small that the addition of a fluidity improver such as hydrophobic silica fine powder is unnecessary or necessary in order to obtain the necessary fluidity. However, it is sufficient to add only a small amount of the added fish, and therefore, the adverse effects caused by adding a large amount of hydrophobic silica fine powder can be avoided. It has a long history of non-agglomeration and has excellent storage stability. Therefore, according to the toner of the present invention, it is possible to achieve good development by having high fluidity and non-cohesiveness, and also to be able to fix at low temperature and high speed.
As a result, an excellent visible image with high image density can be formed in a very stable manner. In addition, since the toner of the present invention has a low minimum fixing temperature, it is possible to avoid exposing the paper, which is the toner image support, to high temperatures during fixing, and as a result, the occurrence of wrinkles is suppressed. It becomes practically possible to form a visible image using toner.

The reason why the above excellent effects can be obtained is that the unmodified wax and modified wax contained in the Q toner are mainly composed of polyolefin, so the minimum fixing temperature of the toner is low. Wax has an excellent effect of imparting non-offset properties, and modified waxes are also effective in imparting non-offset properties, so as a result, the temperature at which toner offset and offset occurs will be lower.・Not only does the degree of decrease in toner fluidity due to the addition of unmodified wax itself be smaller than that in the case of unmodified wax, but also the fact that when unmodified wax is further added, the toner fluidity decreases due to the addition of unmodified wax. This is thought to be partly due to the fact that it has the effect of suppressing the rate of decline in fluidity to a small level, and other reasons. It is presumed that the reason for θ above is that the modified wax has the effect of increasing and stabilizing the compatibility of the unmodified wax with the binder resin, and as a result, the adhesion of the unmodified wax is hidden. Ru.

In addition, the binder resin is a styrene resin and its M
If the value of w/Mn is 3.5 or more, if the polyester resin rarely has a chloroform insoluble content of 5% by weight or more, it is an S-B resin with a molecular weight of ioo, o
In the case where the inner resin itself has low-temperature fixing properties and non-offset properties, the effect of the present invention can be ensured and maintained. [Examples] Examples of the present invention will be described below, but the present invention is not limited to these. In addition, "part" represents a heavy part.

The binder resin and wax used in the following examples are as follows.

[Binder resin]

1) Binder resin A1 obtained by copolymerizing styrene, methyl methacrylate, and n-butyl methacrylate at a weight ratio of 50:20:30, with a ratio of high molecular weight fraction to low molecular weight component. The weight ratio is 40:100, MW-130, QOO1
IVn=s, ooo, Mw/Mn=16.25, copolymer 2 with a softening point of 135°C) Binder resin A2 Terephthalic acid 299f and polyoxypropylene (2,
2) -2,2-bis(4-hydroxyphenyl)propane 2112 and Pentaerys IJ) -ru 82f on the temperature side, stainless steel! ! Place it in a round-bottomed flask equipped with a stirrer, a glass nitrogen gas inlet tube, and a flow 1 type condenser, set the flask on a mantle heater, and introduce nitrogen gas from the nitrogen gas inlet tube to fill the inside of the tube. The VCo was then heated in an inert atmosphere and
, 05f of dibutyltin oxide was added and reacted at a temperature of 200°C while monitoring the reaction at the softening point, resulting in a chloroform-insoluble content of 17% by weight and a softening point of 131°C.
Polyester resin 3) Binder resin A3 (dispersion medium) Water 180 parts (monomer) Butadiene 10 parts Styrene 90 parts Divinylbenzene 0.16 parts (emulsifier) Fatty acid potassium salt 2.2 parts Disproportionated rosin acid potassium salt 2 .2 parts Potassium phosphate 0.4 parts (polymerization initiator system) Ferrous sulfate 0.005 parts Paramenthane hydroberoxide 0.02 parts t-dodecyl mercaptan 0.5 parts or more The polymerization reaction was carried out at a temperature of 5°C in an autoclave with a capacity of 201 liters purged with gas, and when the conversion rate reached 70%, the polymerization terminator N was added.
The reaction was stopped by adding 0.2 parts of N'-diethylhydroxyamine, and 1 part of stabilizer was added to the resulting latex.
After adding 10% of the polymer, a coagulant of calcium chloride is added to coagulate the polymer, which is then dehydrated and dried to obtain a polymer with a molecular weight of 10.
The content of high molecular weight components of 0,000 or more is 41% by weight
, S-B copolymer [wax] with a softening point of 141°C 1) Modified wax a Polyethylene wax that has been kraft copolymerized and tightened with methyl methacrylate (methyl methacrylate content 20% by weight, softening point 120) ℃) 2) Modified wax b Polyethylene wax block copolymerized with methyl methacrylate (methyl methacrylate content: 5
weight f1%, softening point 110°C) 3) Unmodified wax C Polypropylene wax “Viscol 660 pJ (manufactured by Sanyo Chemical Co., Ltd.) For each example and comparative example, the feather of the indicated formulation was melted, A toner consisting of particles with an average particle size of 10 μm was produced by a conventional method including cross-mixing, cooling, crushing and classification steps.

Example 1 Binder 1!4 Fat At 100 parts Modified wax 3 3 parts Unmodified wax 0 1 part Carbon black "Mogul L" (manufactured by Cabot) 10 parts Example 2 Binder resin AI '100 parts ζ Wax b 2 parts (38) Unmodified wax C 2 parts Carbon black "Mogul Lj xos Example 3 Binder resin A2 100 parts Modified wax a 3 parts Unmodified wax 0 1 part Carbon black "Mogul Shi" xO part Example 4 Binder resin AZ Zoo part Modified Wax b 2 parts Undenatured wax 0 2 parts Carbon black "Mogul L J 1o Hy Example 5 Binder Jugetsuji A3 100 μm Modified wax 8 3 parts Unmodified wax C 1 part Carbon black "Mokal Shi" 10 parts Example 6 Binder resin A3 100 parts Modified wax b 2 @ Unmodified wax 0 2 parts Carbon black [Mogul LJ' 10 parts Example 7 Binder resin A1 48 parts Modified wax a 3 parts Unmodified wax C 1 part Magnetic fine powder "BL-100J" (manufactured by Titan Kogyo Co., Ltd.) 52 parts Comparative Example 1 Binder resin Al 100 parts Unmodified wax 0 3 parts Carbon black [Mogul LJ 10 parts Comparative example 2 Binder resin A2 100 parts Unmodified wax 0 3 parts Carbon black [Mogul LJ xo parts Comparative Example 3 Binder resin A3 100 parts Unmodified wax C 3 parts Carbon black Mogul LJ 10 parts Comparative example 4 Binder resin Al 100 parts Modified wax 8 3 parts Carbon black [Mogul LJ 10 parts or more Examples 1 to 2 Each of the toners obtained in Example 7 is called "Toner 1".
- "Toner 7" and the toners obtained in Comparative Examples 1 to 4 were respectively "Comparative Toner 1" to "1-Comparative Toner 4".
The fluidity of each of these toners was investigated.

That is, the degree of compaction was measured using a powder compressibility tester "Tap Denser" (manufactured by Seishin Enterprise Co., Ltd.), taking advantage of the fact that the degree of compaction of powder particles with high fluidity is small. Specifically, diameter 2
8+w, capacity 8t100- container is loosely filled with the sample through a 100 mesh sieve from above, weight IT is measured to determine the static bulk density A, and then the falling height is determined using an upper tapping device with a lid of the same diameter on the container. The volume of the sample when tapped 600 times under the condition of 5 fins was determined, and the previously determined weight was divided by this volume value to determine the solidified bulk density P'lk, and the degree of compression C was calculated using the following formula. .

In addition, by mixing each of the 10 kinds of toners other than Toner 7 with a carrier consisting of resin-coated iron powder, the toner concentration is 2% by weight, and the toner band is 20±1 microcoulomb/ Each developer was used to develop an electrostatic image and transfer a toner image to transfer paper using a photocopying machine [U-Bix 3000 J (manufactured by Konishiroku Photo Industries Co., Ltd.)]. Then, the toner image is fixed by a heated roller fixing device, and the amount of toner primarily adhered to the surface of the photoreceptor drum is determined.
The transfer rate to the transfer paper and the image density of the obtained copied image were measured. Here, the primary adhesion amount of toner is the amount of toner adhesion per unit area at a location where the so-called solid black potential is 800 cm.

All of the toners were evaluated for their minimum fixing temperature, offset generation temperature, and storage stability. Regarding the minimum fixing temperature, we used a heat roller whose surface layer was made of Teflon (polytetrafluoroethylene manufactured by DuPont) and a heated roller whose surface layer was made of silicone rubber rKE-130.
The toner image of the sample toner was transferred onto a 6497 m'' transfer paper using a fixing device formed with a pressure roller formed by 0RTVJ (manufactured by Shin-Etsu Kagaku Kogyo Co., Ltd.) at a linear velocity of 120+.
The fixing operation at II+lI/sec is repeated at each temperature in which the set temperature of the heat roller is raised stepwise by 5 degrees Celsius from 100 degrees Celsius, and the formed fixed image is subjected to Kimwipe rubbing to ensure sufficient scratch resistance. The lowest set temperature for a fixed image showing the properties was defined as the lowest fixing temperature.

Note that the fixing device used here does not have a silicone oil supply mechanism.

In addition, to measure the offset occurrence temperature, the toner image is transferred and fixed using the above-mentioned fixing device, and then a blank sheet is transferred and the paper is sent to the fixing device under the same conditions. The operation of observing whether or not toner stains were generated was repeated with the set temperature of the heat roller 2 of the fixing device raised by 1 degree to determine the temperature at which offset occurred.

Regarding storage stability, each sample was left for 48 hours at a temperature of 55° C. and a relative humidity of 40%, and the presence or absence of aggregation and its degree were evaluated.

The above results are shown in Table 1. In addition, offset occurrence humidity VC
Those marked with an asterisk (*) indicate that no offset phenomenon occurred at that temperature.

The electrophotographic copying machine [
When a continuous copying test was conducted 20,000 times using U-Bix 3000 J, clear and good copied images were formed until the end, regardless of which toner was used.

As is clear from the above results, the toner according to the present invention has
It has excellent non-offset properties, has a very low minimum fixing temperature, and has a wider range of fixable temperatures than toners containing only conventional unmodified polyolefin wax, and has high fluidity and a fluidity improver. It can be put to practical use even without the addition of , has excellent developability and transferability, and can always form stable and good visible images.

Claims (1)

[Claims] 1) Contains a first wax made of polyolefin and a second wax made of polyolefin block copolymerized or graft copolymerized with a σ-methylene aliphatic monocarboxylic acid ester monomer. A toner for developing electrostatic images characterized by: 2) The toner for developing electrostatic images according to claim 1, wherein the total content of the first wax and the second wax is 1 to 20% by weight.