JPH0426858A - Binder resin for toner, production of binder resin and toner - Google Patents

Abstract

PURPOSE:To enhance low temperature fixability and offset resistance of the toner and pulverizability of the toner in producing it by specifying the block or graft proportion of the copolymer. CONSTITUTION:The binder resin is obtained by chemically combining a crystalline polyester with an amorphous vinyl polymer having a weight average molecular weight to number average molecular weight ratio of >= 3.5 and having functional groups capable of combining with this polyester. In this block or graft copolymer, the block or graft proportion indicating the combination proportion of the polyester and vinyl polymer is regulated within 40 - 90%, thus permitting the obtained toner to have each sufficient low temperature fixability, offset resistance, fluidity, and blocking resistance, and pulverizability at the time of production of the toner to be enhanced.

Description

Detailed Description of the Invention The second industrial field of application is a binder resin for toners applied to electrophotography, electrostatic printing, electrostatic recording, etc. and a method for producing the same. The present invention relates to a toner using a binder resin.

2. Conventional technology: For example, in electrophotography, an electrostatic latent image is usually formed by charging and exposing an electrostatic image carrier made of a photoconductive photoreceptor, and then this electrostatic latent image is placed in a binder resin. The toner image is developed using a toner formed into fine particles by adding a coloring agent and the like, and the resulting toner image is transferred to a support such as transfer paper and fixed to form a visible image.

In order to obtain a visible image as described above, it is necessary to fix the toner image, and conventionally, a heat roller fixing method that has high thermal efficiency and can perform high-speed fixing has been widely adopted.

However, in recent years, copying machines have become smaller and faster, making it possible to: ■ suppress overheating deterioration of the copier, ■ prevent thermal deterioration of the photoreceptor, and ■ allow the heat roller to fix after the fuser is activated. To shorten the warm-up time required to raise the temperature to ] In order to improve thermal safety, there is a strong demand for reducing the power consumption of the fixing heater and making it possible to perform the fixing process while keeping the temperature of the heat roller lower. Therefore, the toner is also required to be able to be fixed well at low temperatures.

Furthermore, toners can exist stably as a powder without agglomerating under the environmental conditions of use or storage;
In other words, it is necessary to have excellent anti-blocking properties, and in the heat roller fixing method, which is the preferred fixing method, there is an offset phenomenon, that is, part of the toner that makes up the image is transferred to the surface of the dove roller during fixing, and this is transferred to the surface of the dove roller. Since the toner is likely to re-transfer to the transferred transfer paper and stain the image, it is necessary to provide the toner with performance that prevents the occurrence of the off-set phenomenon, that is, offset resistance.

For this reason, the following techniques have been proposed in the past.

(1) In JP-A-63-27855, crystalline polyester, weight average molecular weight Mw and number average molecular weight 1
A toner is disclosed in which a block copolymer or graft copolymer with an amorphous vinyl polymer having an iMn ratio Mw/Mn of 3.5 or more is used as a binder resin.

(2) JP-A No. 63-27856) describes a block copolymer or graft copolymer of a crystalline polyester and an amorphous vinyl polymer having two or more peaks in its molecular weight distribution. ＼A toner used as an under resin is disclosed.

(3) In JP-A No. 64-35456, a toner in which a block copolymer or graft copolymer of crystalline polyester and a non-quality vinyl polymer is used as the <4-under resin and a heat treatment process is added. A manufacturing method is disclosed.

[The problem that Kuchihathu is trying to solve] However, in the above techniques (1) to (3), all of heat(
A crystalline polyester and an amorphous (amorphous) vinyl polymer are chemically bonded using a reaction caused by amide bonds and epochine group bonds.

However, in the reaction using L,p-)luenesulfonic acid and heat, the pro'7 ratio or grafting ratio, which is the bonding ratio between the crystalline polyester and the amorphous vinyl polymer, was low, and the low-temperature fixability was insufficient. In this case, unreacted crystalline polyesters aggregate with each other to form large domains, and even if a local drop in viscosity occurs during heating, the viscosity of the entire toner particle is reduced. 5) I think about things a lot. In addition, the fluidity of the toner particles is also low because a large domain of the two-crystalline polyester component is formed in each particle.

On the other hand, in the reaction with iso/anate, the terminal 10E of the molecule
Campling bonds between groups occur and the reaction proceeds randomly, resulting in a decrease in blocking rate or grafting. Furthermore, when crystalline polyesters react with each other, they become macromolecules, which has the disadvantage of reducing pulverizability.

The present invention was partially developed based on the above circumstances, and the first object of the present invention is to improve the low-temperature fixing properties and offset resistance of toner, and to improve the toner's manufacturing process. An object of the present invention is to provide a binder resin for toner that can improve crushability.

A second object of the present invention is to provide a method for producing a binder resin for toner that can increase the block rate or graft rate in a copolymer.

The third object of the present invention is to provide low-temperature fixing properties, offset resistance,
The object of the present invention is to provide a toner with good fluidity and blocking resistance.

A fourth object of the present invention is to provide a toner that has low environmental dependence and can provide good image quality even under high temperature and high humidity conditions.

[Means to solve the problem]

In order to achieve the above object, the present inventors have proposed that when a block copolymer or graft copolymer of a crystalline polyester and an amorphous vinyl polymer is used as a binder resin for a toner, the block ratio in the copolymer is Or the graft rate is the toner's low-temperature fixing property, offset resistance,
Focusing on the fact that this is a factor that greatly affects properties such as blocking resistance, we have conducted extensive research into what range of blocking ratio or graph l can be satisfied to impart the above-mentioned excellent properties to toner. As a result, we discovered that sufficiently satisfactory properties can be imparted to the toner when the blocking rate or grafting rate is in the range of 40 to 90%. The present invention was completed by discovering that by chemically bonding polyester and amorphous vinyl polymer, the block rate or graft rate can be efficiently controlled within the range of 40 to 90%.

Therefore, the binder resin for toner of the present invention has a crystalline polyester and a functional group that forms a bond with the crystalline polyester, and has a ratio Mw/Mn of weight average molecular weight Mw to number average molecular weight Mn of 35 or more. It consists of a block copolymer or graft copolymer formed by chemically bonding with an amorphous vinyl polymer, and the block ratio or graft ratio indicating the bonding ratio in the copolymer is 40 to 9.
It is characterized by being 0%.

Furthermore, the toner binder resin of the present invention has a crystalline polyester and a functional group that forms a bond with the crystalline polyester, and has a weight average molecular weight Mw and a number average molecular weight MnO ratio Mw/Mn of 3.5. The above amorphous vinyl polymer is characterized in that it consists of a block copolymer or a graft copolymer chemically bonded by a condensing agent consisting of a reducing agent and an oxidizing agent.

In addition, in the method for producing a binder resin for toner of the present invention, a crystalline polyester, which has a functional group that forms a bond with the crystalline polyester and has a weight average molecular weight M
A block copolymer or It is characterized by forming a graft copolymer.

The toner of the present invention is characterized in that it contains the above-mentioned toner binder resin.

That is, in the present invention, by using a specific copolymer having a block rate or graft rate in the range of 40 to 90% as a binder resin, the crystalline polyester component provides the toner with excellent low-temperature fixability and good melting properties. In addition, the amorphous vinyl polymer component provides the toner with excellent low-temperature fixing properties, offset resistance, bronking resistance, and fluidity.

When synthesizing a block copolymer or kraft copolymer of crystalline polyester and amorphous vinyl polymer, a condensing agent consisting of a reducing agent and an oxidizing agent is used)
By employing this special configuration, it has become possible to synthesize a copolymer with a block rate or graph ha in the range of 40 to 90%.

Hereinafter, the configuration of the present invention will be specifically explained.

Binder resin for toner of the present invention: Basically, it consists of a polyester copolymer or a graft copolymer formed by chemically bonding a crystalline polyester and an amorphous vinyl polymer. be.

The amorphous vinyl polymer must have a functional group that forms a bond with the crystalline polyester used in combination, and the ratio Mw/MnO value of the weight average molecular weight Mw to the number average molecular weight Mn must be 3.5 or more. .

The functional group is preferably a carboquine group, a hydroxyl group, an amino group, or the like. Examples of monomers having functional groups that can be used to obtain amorphous vinyl polymers having such functional groups include acrylic acid, β, β-dimethylacrylic acid, α-ethyl acrylic acid, and methacrylic acid. ,
Fumaric acid, itaconic acid, maleic acid, crotonic acid, hydroxyethyl methacrylate, acryloyloxyethyl monophthalate, acryloyloxyethyl monophthalate, N-hydroquinethyl acrylamide, N-hydroquinethylmethacrylamide, N-methylol acrylamide, Examples include p-aminostyrene and others. A monomer having such a functional group is included in a monomer composition for obtaining an amorphous vinyl polymer in an amount of 0.1 to
It is used in a proportion of 20 mol%, preferably in the range of 0.5 to 10 mol%.

An amorphous vinyl polymer is synthesized from a polymerization composition containing a monomer having a functional group as described above, but there are no particular restrictions on the vinyl polymer that constitutes the main portion of the amorphous vinyl polymer. It's not something you can do. Examples of the vinyl polymer as the main portion include polystyrene, polymethyl methacrylate, polymethyl acrylate, polyvinyl chloride,
Examples include polyvinyl acetate, polyacrylonitrile, and others. Among these, styrene polymers, acrylic polymers, and styrene/acrylic polymers are particularly preferred. Monomers for obtaining such polymers include, for example, styrene, O-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene, p -n-butylstyrene, p-dodecylstyrene, p-methkinstyrene, p-phenylstyrene, p-chlorostyrene,
Methyl acrylate, ethyl acrylate, n-butyl acrylate, 2-ethyl hequin acrylate, lauryl acrylate, stearyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, t-butyl methacrylate, 2-ethyl hequin lauryl methacrylate, stearyl methacrylate, /
Mention may be made of chlorhequinyl methacrylate, dimethylaminoethyl methacrylate, and others. These monomers can be used alone or in combination of several types.

In the amorphous vinyl copolymer used in the present invention,
As mentioned above, it is necessary that the value of the ratio Mw/Mn is 35 or more, and a range of 7 to 30 is particularly preferable. This ratio M
When the value of w/Mn is less than 3.5, it becomes difficult to impart sufficient offset resistance and durability to the toner.

The Mw and Mn values of an amorphous vinyl polymer can be determined by various methods, and there are slight differences depending on the measurement method, but in the present invention, they are defined as values determined by the following measurement method.

That is, Mw and Mn were determined by gel permeation chromatography (GPC) under the conditions described below.
, measure the peak molecular weight.

At a temperature of 40° C., a solvent (tetrahydrofuran) is flowed at a flow rate of 1.2 −/min, and a 3 mg sample weight of a tetrahydrofuran sample solution having a concentration of 0.2 g/20 m is injected for measurement. When measuring the molecular weight of a sample, the molecular weight of the sample is measured 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 line are aligned with the straight line.

1; The reliability of the measurement results is based on the NBS', 06 boristyrene standard sample (Mw=28.
8X10', Mn=13,7xlQ'
This is confirmed by the value of the ratio Mw/Mn (Mw/Mn=2.11) being 2.1t=0.10.

Further, the GPC column to be used is not particularly limited as long as it satisfies the above conditions, but for example, TSK-
GEL, GMH (manufactured by Toyo Soda Co., Ltd.), etc. can be used. Furthermore, the solvent and measurement temperature are not limited to the above conditions, and may be changed to appropriate conditions.

The amorphous vinyl polymer used in the present invention preferably has at least two maximum values in its molecular weight distribution. By using such an amorphous vinyl polymer, the low-temperature fixing properties and offset resistance of the toner can be further improved. Specifically, the amorphous vinyl polymer contains at least two components: a low molecular weight component and a high molecular weight component.
In a molecular weight distribution curve that has a molecular weight distribution that can be divided into groups and is measured by GPC, at least one maximum value is in the range 2X10' to 2X10', and there is a small It is preferable to have at least two maximum values, such as in the range of .

Further, the amorphous vinyl polymer used in the present invention preferably has a glass transition point Tg in the range of 50 to 100°C, particularly 50 to 85°C. When this Tg is less than 50°C, it becomes difficult to impart sufficient blocking resistance to the toner, while when it exceeds 100°C, melt flowability at low temperatures decreases, so that sufficient low-temperature fixability is imparted to the toner. This becomes difficult. Note that the Tg of the amorphous vinyl polymer means the glass transition point of the amorphous vinyl polymer in a state where it is not bonded to a crystalline polyester.

In addition, this glass transition point Tg can be determined by differential scanning calorimetry (
DSC), for example, DSC-20j (manufactured by Seiko Electronics Co., Ltd.).
+n), and the glass transition point was determined from the intersection of the baseline and the slope of the endothermic peak.

The crystalline polyester used in the present invention is not particularly limited, but polyalkylene polyester is particularly preferred from the viewpoint of imparting sufficient low-temperature fixability and fluidity to the toner.

Specific examples of such polyalkylene polyesters include:
Polyethylene sebacate, polyethylene adipate, polyethylene adipate, polyethylene undecane, polyethylene p-(carbophenoquine) undecate, polyhexamethylene sebacate, polyhexamethylene sebacate, polyhexamethylene decanedioate , polyoctamethylene dodecanedioate, polynonamethylene azelate, polydecamethylene adipate, polydecamethylene acelate, polydecamethylene adipate, polydecamethylene sebacate, voltamethylene sacinate, voltamethylene octadecanedioate Eight,
Polytetramethylene sebacate, polytrimethylene dodecanedioate, polytrimethylene octadecanedioate, polydecamethylene acelate, polyhexamethylene decamethylene sebacate, polyquine decamethylene-2-methyl-1,3-propane-dodecane dioates, and others.

The crystalline polyester used in the present invention preferably has a melting point Tm in the range of 50 to 120°C, particularly 50 to 100°C). When this Tm is less than 50°C, it becomes difficult to impart sufficient blocking resistance to the toner, while when it exceeds 120°C, melt fluidity at low temperatures decreases, so that sufficient low-temperature fixability is imparted to the toner. This becomes difficult. In addition, Tm of crystalline polyester is
It refers to the melting point of crystalline polyester when it is not bonded to an amorphous vinyl polymer. Also, this melting point T
m can be measured according to differential scanning calorimetry (DSC), for example, by DSC-20- (manufactured by Seiko Electronics Co., Ltd.);
The melting peak value when g is heated at a constant temperature increase rate (10°C/n++n) is defined as the melting point 'rm.

The crystalline polyester used in the present invention has an Mw of 5.0.
00-50.000, Mn is 2.000-20.000
2 and 2 are preferably in the range of 'J). When the molecular weight is within this range, it is possible to impart excellent anti-offset properties to the toner, and it is also possible to improve the crushability during the production of the toner.

In the present invention, a block copolymer or a graft copolymer obtained by chemically bonding the above crystalline polyester and an amorphous vinyl polymer is used as a binder resin for toner. The proportion of the crystalline polyester component in the polymer is from 3 to 50% by weight, in particular from 5 to 40% by weight.
A range of is preferred. The ratio of crystalline polyester component is 3
When the weight percent is not swirled, it becomes difficult to impart sufficient low-temperature fixing properties to the toner, while when it exceeds 50 weight percent, the melt elastic modulus during fixing becomes small, making it difficult to impart sufficient anti-offset properties to the toner. This becomes difficult.

The crystalline polyester and the amorphous vinyl polymer used in combination to obtain the binder resin for toner of the present invention may be mutually compatible or incompatible, but the blocking resistance of the toner From the viewpoint of improving the properties and crushability during toner production, it is preferable that they are incompatible. Here, "incompatibility" refers to the fact that the chemical structures of the two are the same or similar, or that the two do not have the property of being sufficiently dispersed due to the action of functional groups. .

Value (R, F, Fedors, Polym, Eng
, Sci, , 14. (2) 147 (1974)) whose difference is greater than 0.5.

In the block copolymer or graft copolymer constituting the binder resin for toner of the present invention, the block ratio or graph l indicating the bonding ratio between the crystalline polyester and the amorphous vinyl polymer is in the range of 40 to 90%. It is necessary that there be. If the block rate or graft rate is within this range, sufficient low-temperature fixing properties, anti-offset properties, fluidity, and anti-blocking properties can be imparted to the toner, and the crushability during toner production can be significantly improved. I can do it.

In the present invention, the block ratio or graft ratio is the ratio of the crystalline polyester actually bonded to the amorphous vinyl polymer, out of the added crystalline polyester, before and after the block copolymerization reaction or graft copolymerization reaction. It is calculated from the change in the number of functional groups at the terminals of crystalline polyester molecules. Specifically, 'H-NMR (e.g. F
This value was calculated as follows using TNMR, GX-400 (manufactured by JEOL Ltd.).

That is, for example, in the following crystalline polyalkylene polyester CI having a hydroxyl group at the molecular end, the proton (b) of the methylene group bonded to the oxygen atom has 3
．． 6 to 3.7 ppm, while the signal of the proton (a) of the methylene group bonded to the hydroxyl group at the end of the molecule is 4.
0-4. lppm, and from these intensity ratios, the ratio of the number of hydroxyl groups at the terminals of the crystalline polyester molecules (a) to the number of methylene groups bonded to oxygen atoms (b) can be determined. In the same way, the ratio of the number of hydroxyl groups at the end of the molecule of the crystalline polyester in the block copolymer or graft copolymer to the number of methylene groups bonded to oxygen atoms is determined, and the number of hydroxyl groups at the end of the molecule before and after the reaction is calculated using the formula = Calculate the block rate or graft rate from the change in .

× In the toner binder resin of the present invention, the crystalline polyester and the specific amorphous vinyl polymer are
It is preferable to use a block copolymer or a graft copolymer chemically bonded by a condensing agent consisting of a reducing agent and an oxidizing agent.

Examples of the condensing agent consisting of such a reducing agent and an oxidizing agent include evatriphenylphosphine-disulfide type, triphenylphosphine-polyhalide L) IJ phenylphosphine-carbon tetrachloride-imidazole type, vicrylupyridine chloride type, Examples include phosphite triester-thionyl chloride.

The condensing agent consisting of a reducing agent and an oxidizing agent is preferably used in an amount equivalent to the amount of functional groups present in the crystalline polyester and amorphous vinyl polymer used. When the amount of condensing agent used is too small relative to the functional group concerned, it is difficult to increase the grafting ratio of the block*star.

Such a block copolymer or graft copolymer can be produced, for example, by dissolving a crystalline polyester and an amorphous vinyl polymer in a solvent to prepare a homogeneous solution, which is then subjected to a condensation process consisting of a reducing agent and an oxidizing agent. It can be produced by gradually dropping a solution in which the agent is dissolved to allow the reaction to proceed.

Furthermore, in order to increase the blocking rate or grafting rate, it is preferable that one of the crystalline polyester and the amorphous vinyl polymer has a carboxyl group as a functional group, and the other has a hydroxyl group and/or an amino group as a functional group. As explained above, the binder resin for toner of the present invention is made of a specific copolymer and has a block ratio or graph l in the range of 40 to 90%, so the crystalline polyester component makes the toner excellent. It is possible to impart excellent low-temperature fixing properties and good wetting properties during melting, and the amorphous vinyl polymer component also imparts excellent low-temperature fixing properties, offset resistance, bronking resistance, and fluidity to the toner. It's coming.

On the other hand, when the block rate or graph l is less than 40%, it is not possible to impart sufficient low-temperature fixability to the toner, and the domains of the crystalline polyester component in the toner particles become large, causing the toner to decreases the liquidity of On the other hand, when the grafting rate or grafting rate exceeds 90%, the crystalline polyester component in the copolymer becomes compatible with the amorphous vinyl polymer component, lowering the glass transition temperature of the copolymer. This makes it difficult to impart sufficient blocking resistance to the toner.

Next, the toner of the present invention will be explained. The toner of the present invention uses the specific copolymer described above as a binder resin, and contains toner components such as a colorant, a magnetic material used as necessary, and a property improver. . In addition, in the toner of the present invention, other resins may be used in combination as binder resins in addition to the above-mentioned specific copolymers. However, the content of the specific copolymer in the entire binder resin is preferably 30% by weight or more, particularly preferably in the range of 50 to 100% by weight.

Examples of colorants used in toner include carbon black, nigrone dye (C, 1, Nα50415B)
, aniline blue (C, 1, No50405), calco oil blue ([:, l, No, azo+c B
lue 3), Chrome x Low (C, l, No,
14090), ultramarine blue (C, l,
Nα77103), DuPont Oil Red (C, I
.

\lo, 26105), Kinoline x Lo (
C, I, No, 47005), methylene blue chloride (C, I, Nα52015), phthalo/
Annine Blue (C, I, No. 741.60), Malachite Green Off Sarate (C, I, No.
42000), o-zbengali (C, l, No
45435), a mixture of these, and the like. The amount of the coloring agent used is usually in the range of 01 to 20 parts by weight, particularly preferably 0.5 to 10 parts by weight, per 100 parts by weight of the toner.

Magnetic materials used in toner include ferrite, fugnetite, iron, cobalt, nickel, and other ferromagnetic metals or alloys, or compounds containing these elements, or compounds that do not contain ferromagnetic elements but have been subjected to appropriate heat treatment. Alloys that exhibit ferromagnetic properties when subjected to oxidation, such as alloys called Heusler alloys containing manganese and copper, such as manganese-copper-aluminum, manganese-copper-tin, chromium dioxide, and others. can. For example, when obtaining a black toner, magnetite is preferred because it is black in itself and also functions as a coloring agent. Further, when obtaining a color toner, it is preferable to use a material with little darkness, such as metal iron. Some of these magnetic materials also function as a coloring agent, and in that case, they may also serve as a coloring agent. These magnetic substances are contained in the form of fine powder with an average particle size of 0.1 to 1 μm. In magnetic toner, the content is preferably 20 to 70% by weight of the toner, particularly 40 to 70% by weight.
is preferred.

Properties improving agents used in toners include fixability improving agents, charge control agents, and the like.

Examples of fixability improvers include polyolefin in wax, fatty acid metal salts, fatty acid esters and fatty acid ester waxes, partially saponified membrane fatty acid esters, higher fatty acids,
Fluid or solid paraffin wax, polyamide wax, polyhydric alcohol ester, silicone resin, aliphatic fluorocarbon, etc. can be used.

In particular, the softening point (ring and ball method JIS K 2531) is 60~
Wax at 150°C is preferred.

As the charge control agent, conventionally known ones can be used. Examples include nigrosine dyes and metal-containing dyes.

In one example of the method for producing the toner of the present invention, a binder resin containing at least the above-mentioned specific copolymer and toner components such as a colorant are mixed, the mixture is melt-kneaded using, for example, an extruder, and after cooling, a jet The particles are pulverized using a mill or the like, and then classified to produce a toner having a desired particle size.

In another example of the toner manufacturing method of the present invention,
A toner having a desired particle size is produced by melting and kneading the toner using an extruder or the like in the same manner as described above, and spraying or dispersing it in a liquid in a molten state using a spray dryer or the like.

Further, in the present invention, the toner may be constituted by adding and mixing inorganic fine particles such as a fluidity improver to the toner obtained as described above.

Such inorganic fine particles have a -order particle diameter of 5 nm to 2 μ.
In particular, m1 is preferably in the range of 5 nm to 500 nm. In addition, the BET specific surface bond of inorganic fine particles is 20 to 500.
A range of m'/g is preferred.

The proportion of the inorganic fine particles added is preferably in the range of 0.01 to 5% by weight, particularly 0.01 to 2.0% by weight, based on the total toner.

Examples of constituent materials of the inorganic fine particles include silica, alumina, titanium oxide, barium titanate, cerium titanium oxide, carunium titanate, strontium titanate, zinc oxide, silica sand, clay mica, wollastonite, diatomaceous earth,
Examples include chromium oxide, cerium oxide, red iron oxide, antimony dioxide, heptadonium oxide, zirconium oxide, barium sulfate, barium carbonate, carbonate, silicon carbide, and silicon nitride. Among these, particularly preferred is the nori powder.

The silica fine powder referred to herein is a fine powder having Sl-0-81 bonds, and may be produced by either a dry method or a wet method. In addition to anhydrous silicon dioxide, any of aluminum silicate, sodium silicate, potassium silicate, cerium silicate, zinc silicate, etc. may be used, but those containing 5iCh in a proportion of 85% by weight or more are preferable.

As specific examples of these/silica fine powders, there are various commercially available silicas, but those having hydrophobic groups on the surface are preferable, such as AERO5IL R-972, R94, R-8.
05, R-812 (manufactured by Aeronol), Talax 500 (Tulco!), etc.Other examples include Nlankanobbling agent, titanium campling agent, /recon oil, and having an amine in the side chain/ It is also possible to use a fine powder treated with recon oil or the like.

The toner of the present invention is used to develop an electrostatic latent image formed in, for example, an electrophotographic copying machine, and the obtained toner image is electrostatically transferred onto transfer paper and then fixed by a heating roller fixing device to be copied. An image is obtained. The toner of the present invention is particularly preferably used when fixing is performed at a high speed such that the contact time between the toner on the transfer paper and the heating roller is, for example, within 1 second, particularly within 0.5 seconds.

〔Example〕

Examples of the present invention will be explained below along with comparative examples, but the present invention is not limited to these embodiments. In addition, below, "part-1" represents 11 parts.

<Crystalline polyester 1> 1500 g (7.41 mol) of sebanic acid and 964 g (8.16 mol) of hexamethylene glycol,
Place the flask in a 51 volume round bottom flask equipped with a thermometer, stainless steel stirrer, glass nitrogen inlet tube and sinking condenser, then place the flask in a heating mantle and inject nitrogen gas through the glass nitrogen inlet tube. was introduced into the reactor to raise the temperature while keeping the inside of the reactor surrounded by inert snow. Then, 13.2 g of p-toluenesulfonic acid was added and reacted at a temperature of 150°C. When the amount of water flowing out due to the esterification reaction reached 250 -, the reaction was stopped and the reactant was taken out. This was cooled to room temperature to obtain a crystalline polyester 1 made of polyhexamethylene sebacate having a hydroxyl group at the end of the molecule. The melting point Tm of this crystalline polyester 1 was 64°C. However, melting point T
m is a value measured using a differential scanning a-pointer-DSC-20° (manufactured by Seiko Electronics Industries, Ltd.). Moreover, the weight average molecular weight Mw of the crystalline polyester 1 was 12.300.

<Crystalline polyester 2> Tm-
Crystalline polyester 2 made of polyethylene sebacate at 70° C. and Mw=11,000 was obtained.

<Crystalline Polyester 3> By the same manufacturing method as Crystalline Polyester 1, Tm=
A crystalline polyester 3 made of polydecamethylene adipate at 74° C. and Mw=13,100 was obtained.

Amorphous vinyl polymer 1> Put 100 parts of toluene into a separable flask with a capacity of 1β, and add 75 parts of styrene and 2 parts of butyl acrylate.
．． After adding 5 parts and 01 parts of benzoyl peroxide and replacing the gas phase in the flask with nitrogen gas, the temperature was increased to 80°C.
The first stage polymerization was carried out by raising the temperature to 150°C and maintaining the temperature for 15 hours.

Thereafter, the inside of the flask was cooled to a temperature of 40°C, and 85 parts of styrene and 10 parts of butyl methacrylate were added thereto.
Add 5 parts of acrylic acid and 4 parts of benzoyl peroxide,
After continuing stirring for 2 hours at a temperature of 40°C, the temperature was increased to 80°C.
The temperature was raised again to .degree. C. and maintained at that temperature for 8 hours to carry out the second stage polymerization.

Next, add 0 zinc oxide, which is a polyvalent metal compound, to the flask.
, 5 g was added thereto, and the reaction was carried out for 2 hours while maintaining the temperature at reflux and stirring.

Thereafter, toluene was distilled off using an aspirator and a vacuum pump, and the mixture was dried to produce an amorphous vinyl polymer I in which zinc oxide reacted with the carboxyl groups of the vinyl polymer to form ionic crosslinks. Note that this amorphous vinyl polymer 1 has a carboxyl group as a functional group for bonding with the crystalline polyester.

This amorphous vinyl polymer 1 has two peaks in the molecular weight distribution determined by GPC, the peak molecular weight on the high molecular weight side is 251,200, and the peak molecular weight on the low molecular weight side is 4.
It is 000. In addition, the weight average molecular weight Mw is 93.20
0, the value of Mw/Mn is 18.4, the glass transition point Tg
is 60°C, and the softening point Tsp is 128°C.

Amorphous vinyl polymer 2> Styrene 85 parts n-butyl methacrylate 10 parts Acryloyl Mando/Nichirumo/Saku/Nate 5 parts Benzoyl peroxide 4 parts The monomer mixture with the above composition was added to 1 volume by adding 100 parts of toluene. After replacing the gas phase in the flask with nitrogen gas, the temperature was raised to 80°C and maintained at this temperature for 15 hours to carry out polymerization. after that,
By distilling off toluene using an aspirator and a vacuum pump, styrene containing a carboxyl group is produced.
Amorphous vinyl polymer 2, which is an acrylic resin, was obtained.

This amorphous vinyl polymer 2 has one peak at ) in the molecular weight distribution determined by GPC, and the peak molecular weight is 65.
It was 000. Also, Mw is 71.000, ratio Mw/
The Mn value was 7.5, Tg was 67°C, and Tsp was 123°C.

<Amorphous vinyl polymer 3> In the production of amorphous vinyl polymer 1, the monomer charges for the first stage polymerization were changed to 15 parts of styrene, 5 parts of butyl acrylate, and 0.04 parts of benzoyl peroxide. Amorphous vinyl polymer 3 was obtained in the same manner.

This amorphous vinyl polymer 3 has two peaks in its molecular weight distribution by GPC, the peak molecular weight on the high molecular weight side is 363.000, and the peak molecular weight on the low molecular weight side is 7.000.
It is 590. Also, Mw is 165.000, ratio Mw/
Mn value is 25.9, Tg is 62°C, Tsp is 130
It is ℃.

Amorphous vinyl polymer 4> Amorphous vinyl polymer was prepared in the same manner as in Amorphous vinyl polymer 3) except that 5 parts of acrylic acid, which was the monomer in the second stage polymerization, was changed to doroquine ethyl methacrylate 5B. Polymer 4 was obtained. This amorphous vinyl polymer 4 has a hydroxyl group as a functional group for bonding with the crystalline polyester, and has two peaks in the molecular weight distribution by GPC, with the peak molecular weight on the high molecular weight side being 395.00.
0, the peak molecular weight on the low molecular weight side is 9.430. Further, Mw is 174.500, the ratio M w /Mn is 23.7, Tg is 63°C, and Tsp is 128.5°C.

Copolymer A> Crystalline polyester 1 225 g (15 parts)
Amorphous vinyl polymer 1 1275 g (85 parts) or more of the material was added to Kinren 1.5, i! The capacity is 5! The reactor was placed in a separable flask, and nitrogen gas was introduced to maintain the inside of the reactor in an inert atmosphere, and the temperature was raised. When the crystalline polyester and the amorphous vinyl polymer are completely dissolved in quintylene to form a homogeneous solution, 102 g of triphenylphosphine is used as the reducing agent and 2.2 g as the oxidizing agent.
A solution of 18.7 g of a condensing agent consisting of 8.5 g of °-dipyridyl disulfide dissolved in 100 d of xylene was added dropwise from the dropping funnel, and then refluxed at a temperature of 150° C. for 1 hour. Next, after xylene was distilled off using an aspirator and a vacuum pump, the reaction product was taken out and cooled to room temperature to obtain copolymer A.

Copolymer B> Crystalline polyester 1 225 g (15 pieces)
Amorphous vinyl polymer 2 1275 g (85 parts)
Copolymer B was obtained in the same manner as Copolymer A using the above materials.

Copolymer C> Crystalline polyester 1 225 g (15% amorphous vinyl polymer 3 1275 g (85 parts)
Using the above materials, Copolymer C was obtained in the same manner as Copolymer A in 5).

Copolymer D> Crystalline polyester 2 225 g (15 parts)
Amorphous vinyl polymer 1 A copolymer was obtained in the same manner as Copolymer A using 1275 g (85 parts) or more of the material.

Copolymer E> Copolymer E was obtained in the same manner as in the production of Copolymer A, except that the amount of the droplet solution containing the condensing agent dissolved therein was reduced by half.

<Copolymer A Crystalline Polyester 3 375 g (25%)
Amorphous vinyl polymer 3 1125 g (75 evil)
Using the above materials, add 204 g of triphenylphosphine as a reducing agent and 2,2''-nopyridyldisulfide Ml-,,O
A comparative copolymer a was obtained in the same manner as copolymer A, except that the solution was changed to a solution in which 3", 4 g of the condensing agent G or G was dissolved in 100 ml of kylene.

Copolymer b> In the production of copolymer BC'),
A comparative copolymer was obtained in the same manner except that the ethylene solution was changed to p-toluenesulfonic acid 0.058 (S).

Copolymer C> A comparative copolymer C was obtained in the same manner as in the production of copolymer C, except that the solution containing the condensing agent dissolved therein was changed to 0.0 + p-)luenesulfonic acid. .

Copolymer d> Crystalline polyester 2 225 g (15 parts)
Amorphous vinyl polymer 4 1275 g (85 parts) or more of material was used, and the same procedure as copolymer A was made for comparison, except that 2 parts of hexamethylene diisonoanate was used instead of the cinnabar solution in which the condensing agent was dissolved. A copolymer d was obtained.

<Example 1> To the copolymer 100 parts carbon black 10 parts paraffin wax 3 parts alkylene bis fatty acid amide 3 parts or more of the materials were placed in a V-type mixer, mixed for 20 minutes, and melt-kneaded using a twin-screw extruder. After cooling, it is coarsely ground in a Wiley mill to obtain a 2 mm main-yubas product, which is further finely ground in a supersonic gent mill, and then in step 5), fine powder with a particle size of 5 μm or less is removed using an air classifier to obtain colored particles with an average particle size of 11 μm. I got it.

Toner 1 of the present invention was prepared by mixing 0.8 parts of silica and 0.05 parts of zinc stearate with 100 parts of the colored particles using a V-type mixer.

<Examples 2 to 5> In Example 1, copolymer A was replaced with copolymer B.

Toners 2 to 5 of the present invention were produced in the same manner except that C, D, and E were changed.

Comparative Examples 1 to 4> In Example 1), copolymer A was replaced with copolymer a.

Use the same 1i except for changing to b, c, and d, and use toners 1 to 4 for comparison! ! Built.

<Evaluation> Each toner obtained in the above Examples and Comparative Examples was evaluated on the following items, and the results were summarized in Section 1 below.
Shown in the table.

[Grafting ratio of binder resin]

The ratio of the main chain methylene fugnal strength to the terminal methylene fugnal strength of the crystalline polyester was measured by H-NMR, and from the degree of decrease before and after the graft reaction, the graph l for the graft copolymer was calculated using the already described formula V: Calculated using

[Crushability during toner production]

Average particle size when pulverized with jet mill PJM-100J (manufactured by Japan New 7 Chitsuku Kogyo Co., Ltd.): 10
The amount of feed necessary to obtain μm was measured and used as an index of crushability. Discharge air pressure6. Supplied at Okg/cm2 115
g/++++n or more "O=, 5~15 g/+n
Less than +n was defined as "X".

:Fluidity of toner] Utilizing the fact that the powder has high fluidity and low compressibility, each toner was loosely packed from above into a container with a diameter of 23 mm and a volume of 100 d, and its weight was measured. Then, the static bulk density of the toner was determined. In the evaluation, the static bulk density was 10-10 when it was 040 g/d or more, and -x- when it was 40 g/m.

Cohesiveness of Rottoner] 2 g of each toner was placed in a sample tube, tapped 500 times with a tap densityer, and then the temperature was 60°C and the relative humidity was 3.
4%=Release in an atmosphere for 2 hours! After that, the mixture was separated using a 43-menu sieve, and the proportion of aggregates remaining on the sieve was measured.

Low-temperature fixability of this toner] Each toner was mixed with a coachite carrier in which a fluorinated alkyl methacrylate polymer was coated on a ferrite core material with an average particle size of 80 μm at a ratio of 2% by weight, and its content (toner concentration) was determined. A two-component developer containing 5% by weight was prepared.

Made of organic photoconductive semiconductor. @Equipped with an image carrier, a developing device for two-component developer, and a heating roller constant M device, it has been modified so that the set temperature of the adder can be variably adjusted. The linear speed of the heating roller was increased to 139 by using a modified machine of 1550MR (manufactured by ml Nika).
mm 7 seconds, and while keeping the temperature of the pressure roller lower than the set temperature of the heating roller, set the set temperature of the heating roller to 10 seconds.
An actual photographic test was conducted in which a fixed toner image was formed using each of the above developers while changing the temperature stepwise within the range of 0 to 240°C), and the edges of the obtained fixed toner image were rubbed. After rubbing with a testing machine under a constant load, the residual rate of the image at the edge was measured using a microden/tometer, and the lowest set temperature (minimum fixing temperature) at which the residual rate was 80% or more was determined. Note that the heating roller fixing device has a surface layer made of PFA.
A heating roller with a diameter of 30 mm made of (tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer) and a surface layer coated with PFA: silicone rubber rKE-130ORTV= (manufactured by Shin-Etsu Chemical Co., Ltd.)
The pressure roller has a linear pressure of Q0gkg.
/cm, the nip width is 4.3 mm, and it is unique in that it is equipped with a mechanism for applying a release agent such as silicone oil.

[Toner hot offset resistance]

A fixed toner image was formed in the same manner as above [Low-temperature fixability of toner] except that the pressure roller was kept at a temperature close to the set temperature of the heating roller, and immediately after that, a blank recording material was heated under the same conditions. At each set temperature of the heating roller, an operation of visually observing whether or not toner stains occur on the heated O-roller fixing device is carried out, and the highest set temperature (which does not cause toner stains) is carried out. offset allowable temperature) was determined.

[High temperature and high humidity environmental conditions (temperature 33℃, relative humidity 80%)
Image quality] Electrophotographic copying machine rUB+x 155 equipped with the above-mentioned organic latent image carrier, a developing device for two-component developer, and a heating roller fixing device
0MR = A photocopy test was conducted using a modified machine (manufactured by Konica ■) to form a copy image using each of the above developers under high temperature and high humidity environmental conditions (temperature 33°C, relative humidity 80%). The image quality of the blurred images was visually evaluated.

From Table 1, it can be seen that the grafting rate is 40 to 90% as in the present invention.
A toner containing a specific copolymer in the range of Akashi is the best.

On the other hand, in Comparative Example 1, since it was used as a binder resin and the grafting rate of the copolymer exceeded 90%, it It is a shame that it is inferior to the present invention in terms of image quality.

In addition, in Comparative Examples 2 to 4, the grafting rate of the copolymer used as the binder resin was less than 40%. It is clear that this invention is inferior to the present invention in this respect.

: Effect of the invention 2 According to the binder resin for toner of the present invention, since it is composed of a specific copolymer having a Fronk ratio or a graft ratio of 40 to 90%, it imparts sufficient low-temperature fixability and high fluidity to the toner. It is also possible to improve the crushability during toner production.

According to the method for producing a binder resin for toner of the present invention, a condensing agent consisting of a reducing agent and an oxidizing agent is used17), so a specific copolymer with a high block rate or craft rate can be efficiently produced. can do.

Further, since the toner of the present invention contains the above-mentioned specific binder resin for toner, it has excellent fluidity, bronkink resistance, low temperature fixing property, and hot offset resistance, especially when used at high temperatures and high humidity. Good image quality can be reproduced even under environmental conditions.

Claims (4)

[Claims] (1) A crystalline polyester having a functional group that forms a bond with the crystalline polyester and having a weight average molecular weight Mw
and an amorphous vinyl polymer having a number average molecular weight Mn ratio Mw/Mn of 3.5 or more. A binder resin for toner, characterized in that a block rate or graft rate indicating a bonding rate is 40 to 90%. (2) A crystalline polyester having a functional group that forms a bond with the crystalline polyester and having a weight average molecular weight Mw
A block copolymer or A binder resin for toner comprising a graft copolymer. (3) A crystalline polyester having a functional group that forms a bond with the crystalline polyester and having a weight average molecular weight Mw
and an amorphous vinyl polymer having a number average molecular weight Mn ratio Mw/Mn of 3.5 or more are chemically combined using a condensing agent consisting of a reducing agent and an oxidizing agent to form a block copolymer or graft. A method for producing a binder resin for toner, which comprises forming a copolymer. (4) A toner comprising the toner binder resin according to claim 1 or 2.