JPS59223450A - Toner for pressure fixing - Google Patents

Abstract

PURPOSE:To obtain a toner which exhibits substantial pressure fixability by incorporating thermoplastic rubber and waxy material respectively in the ratios of a specific range into a toner. CONSTITUTION:A toner contains 6-20pts.vol. thermoplastic rubber and 15-35 pts.vol. waxy material by 100pts.vol. the toner in which the sum of the thermoplastic rubber and the waxy material is 25-45pts.vol. The thermoplastic rubber is enumerated by a diene polymer such as butadiene, isoprene or the like or the copolymer thereof, an olefinic polymer or the copolymer thereof, uncrosslinked natural rubber, etc. The waxy material is enumerated as beeswax, shellac wax, microcrystalline wax, etc. as the natural substances. The synthetmic wax is preferably a low mol.wt. polyolefin alone such as low mol.wt. PE, PP or grafted PE and the copolymer thereof and further the oxide and halide thereof or fatty acid wax and the deriv. thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a dry toner composition for developing electrical latent images in electrophotography, electrostatic recording, etc., and particularly to a toner composition having pressure fixability.

<Prior Art> The method of forming an electrical latent image is well known in the art. For example, in electrophotography, a photoconductor layer is usually charged and then a light image based on an original image is irradiated to form a light-irradiated area. The electrostatic charge is reduced or eliminated to form an electrostatic latent image. This latent image is then developed with a developer called toner. As is well known, development methods are broadly divided into methods using wet developers and methods using dry developers, and the latter is a two-component development method that uses two particles, a carrier and a toner, and a method that uses only toner. It is classified as a one-component development method.

The image developed in this way is transferred to paper, etc., if necessary, and then heated to melt the toner, or to harden the toner's binder resin with a solvent, or simply by pressure. It deforms the toner and fixes it on paper, etc.

The pressure fixing method, which fixes toner using only pressure without using heat or solvent, has many advantages over other fixing methods, such as energy saving, no pollution, no risk of fire, and no need to preheat the fixing device. However, the property of the toner to be pressure-sensitively deformed in response to practical pressure is contradictory to the strength of the fixed toner image, toner manufacturability (easiness of manufacture), blocking resistance, impact resistance, etc. Because there is
Satisfying all of these characteristics is an extremely difficult problem, and much research and development has been carried out in the past.

For example, in the Japanese Patent Publication No. Shoti Il-qggo, carbon numbers of
Toner containing 2S aliphatic components is also available from Tokukaisho! ;, 2-
Publication No. //923/ proposes a toner containing a crystalline wax and an ethylene-vinyl acetate copolymer.

In such cases, if the toner contains a wax-like substance to an extent that imparts sufficient pressure-sensitive deformability, the wax-like substance may adhere to the surface of the photoreceptor, or when used as a two-component developer, the wax-like substance may adhere to the surface of the carrier. It has the disadvantage of being easy to adhere to. In addition, the strength of the fixed image is weak, and if the fixed image is rubbed with a finger or the like, the image will be seriously contaminated. Furthermore, when such toner is manufactured by the cross-wire pulverization method, the friction between the raw materials is inhibited by the slipperiness of the wax-like substance during cross-wire crushing, and internal heat generation is difficult to occur, making it difficult to melt the raw materials. .

When heated and kneaded, it is possible to melt the raw materials, but the viscosity of the melted wax-like substance is significantly lower than that of other resins, making it difficult to mechanically mix the two.

On the other hand, JP-A-1/-g-7! ;033 and JP-A-Sho'i
-g-'ygqai publication proposes using a block copolymer or the like consisting of a hard resin and a soft resin to satisfy many of the above-mentioned required properties. In such a case, if the amount of the soft component is increased to the extent that sufficient pressure-sensitive deformability is imparted to the toner, it becomes impossible to crush the toner when the toner is prepared by cross-mixing or a crushing method. Furthermore, since the glass transition by-product of the soft component is lower than that at room temperature, blocking resistance in high temperature environments is poor. Some of the above problems can be avoided if the toner is manufactured by a method other than the mixed wire crushing method, such as a spray drying method or a direct polymerization method. However, these methods are inferior to the cross-wire pulverization method in that they cannot be produced in large quantities at low cost, do not require vinegar, and are affected by residual solvents and residual monomers.

As described above, to date, no toner has been found that satisfies the basic characteristics such as toner manufacturability, blocking resistance, and impact resistance, and also exhibits sufficient pressure fixability.

<Object of the Invention> Accordingly, an object of the present invention is to provide a toner that exhibits sufficient pressure fixability.

Another object of the present invention is to provide a pressure fixing toner with good manufacturability.

Still another object of the present invention is to provide a toner for pressure fixing that has excellent blocking resistance, impact resistance, and powder fluidity.

<Structure of the Invention> The above object is to contain 6 to 0 parts by volume of thermoplastic rubber and 7 to 35 parts by volume of waxy substance in the toner/θθ volume part, and to contain a mixture of thermoplastic rubber and waxy substance. Japanese is #2
This can be achieved by using a toner that is characterized by being dispersed in an S-da S capacitor.

In order for the toner to exhibit optical pressure fixing properties, it is necessary for the toner to undergo significant pressure-sensitive deformation in the pressure fixing device and to obtain a large contact surface with the paper. In an ordinary pressure fixing device, the surface pressure is approximately 200 #/cnt because of the necessity of not damaging the paper or imparting excessive gloss to the paper or the fixed image. Further, this level of surface pressure is appropriate from the standpoint of making the fixing device lightweight and inexpensive. The present inventors use a quantity called powder porosity V20G to express the degree of deformation of toner when it is deformed in a pressure fixing device, that is, when compressed with a pressure of about 200 Jcf/cd. ing.

The method for measuring V2O0 is as follows.

A cylinder with cross-sectional area /d is filled with toner of /~2I,
The toner is solidified by compression using a piston at a pressure of 2001&/Cyfl.

The volume fraction of voids remaining in this solidified toner sample is called ☆oo. If the true specific gravity of the toner is ρ and the apparent specific gravity of the solidified sample is ρa, V2O6 is vgoo =
It is determined by (ρ-ρa)/ρX 100 (%).

vzo.

The smaller the value, the greater the pressure-sensitive deformability of the toner, which is advantageous for pressure fixing.

The present inventors systematically prototyped various pressure fixing toners, measured their pressure fixability and VIlooo, and found that Vt
It has been found that sufficient pressure fixing properties can only be obtained when oo is /4% or less. Additionally, VIlooo
It has been found that in order to control the temperature to 76% or less, it is better to simultaneously contain a thermoplastic rubber and a wax-like substance in the toe. i) By controlling V2O6 to 76% or less by containing only thermoplastic rubber, the thermoplastic rubber has too many leaves and cannot be crushed when produced by the cross-wire crushing method. Moreover, the heat blocking property is inferior in a high width environment. On the other hand, if V2O0 is controlled to less than 100% using only a waxy substance, the amount of waxy substance is too large, the impact resistance of the toner is poor, and the strength of the pressure-fixed image is weak.

Furthermore, when produced by the mixed wire pulverization method, it becomes extremely difficult to knead.

Only when a thermoplastic rubber and a wax-like substance are simultaneously included as a pressure-sensitive deformable material, even if enough pressure-sensitive deformable material is added to reduce V2O6 to less than 20%, the productivity, impact resistance, and blocking resistance are improved. No more problems with sexuality etc. This is because there is no need to contain a large amount of each alone. Furthermore, thermoplastic rubber overcomes the drawbacks of using wax-like substances in that it enhances the frictional heat generation effect between the raw materials and the material during cross-contact, and also enhances the image strength of the pressure-fixed image.

The amount of waxy substance to be contained in the toner is from /S to 35 parts by volume, preferably 20 parts by volume, based on 100 parts by volume of the toner.
~30 parts by volume. In the specification and claims of the present application, "capacity part" refers to an apparent capacity part. Therefore, to find parts by weight from "parts by volume", it is sufficient to multiply by the apparent specific gravity of each powder. If the amount of waxy substance is less than /S, it is difficult to control vzoo to /6 or less unless a large amount of rubbery substance is included. Further, if the number of toners is larger than the 3S capacity part, it becomes difficult to mix up the raw materials, and other problems arise, such as poor impact resistance of the toner and weak image strength of the pressure-fixed image.

The amount of rubbery substance to be contained in the toner is as follows: Toner 1
00 volume parts, 6 to 2[theta] volume parts, preferably g~/g/g volume parts. Answer 6: If the corrosion area is small, it is difficult to control VIloo to 76% or less unless a large amount of waxy substance is included. If the amount is more than 20 parts, it will be difficult to crush, and even if it can be crushed, the heat blocking properties will be poor. Moreover, such fixed toner images tend to peel off easily when rubbed with fingers. The sum of the thermoplastic rubber and waxy substance to be contained in the toner is 2. ! --1. The capacity part,
Preferably, the range is 30 to 30g. If the capacity is smaller than the S capacitance, V2O0 cannot be lower than /ochi.

On the other hand, if the amount is larger than the DaS capacity, Goo can be made smaller, but the fluidity of the toner as a powder will be extremely poor.

The term "thermoplastic rubber" used in the present invention refers to a substance that is different from ordinary crosslinked rubber and exhibits rubber-like elasticity, but can flow like a liquid under a wide range. For example, a substance with a glass transition temperature below room temperature exhibits such properties if its molecular weight is above the molecular weight that forms so-called "entanglement", that is, the critical molecular weight.

For example, diene polymers such as butadiene and isoprene or copolymers thereof, olefin polymers or copolymers thereof (e.g. polyethylene, dilipropylene),
Vinyl acetate polymer or its copolymer tyrene oxide)
, silicone resin, urethane polymer, polyester (for example, polyalkylene adipate), uncrosslinked natural rubber, and the like. Furthermore, such properties can also be exhibited when molecules have interactions due to functional groups such as hydrogen bonds, when they are partially crosslinked, or when they have a structure with an interpenetration temperature.

Furthermore, components with a glass transition temperature above room temperature (hard components)
Block or graft copolymers of components (soft components) whose temperature is lower than room temperature are also suitable for thermoplastic rubbers, and these thermoplastic rubbers can be suitably used in the present invention.

As the hard component, styrenic polymers (such as polystyrene, poly(
(halostyrene), poly(methylstyrene), homopolymers of acrylic acid or methacrylic acid or copolymers with other polymerizable monomers, alkyl methacrylate polymers or copolymers thereof (e.g. polyvinyl chloride), polysulfones. , polyamides, polyesters (eg, polyethylene isophthalate), polycarbonates, and the like.

As soft components, diene polymers such as putazoene and isogrene or their copolymers, olefin polymers or their copolymers (e.g. polyethylene, polyzolopyrene), vinyl acetate polymers or their copolymers, alkylene oxides, etc. Polymers (e.g. polyethylene oxide), silicone resins, urethane polymers, polyesters (
For example, polyalkylene assophate).

The block copolymer or graft copolymer can be easily produced from the monomers forming the above-mentioned hard component and soft component using known techniques. Further, the "wax-like substance" used in the present invention refers to a substance that is solid at room temperature and exhibits plastic flow or viscous flow when stress such as shearing is applied. Examples of natural waxes include beeswax, shellack wax, wool wax, carnauba wax, candelilla wax, auriculie wax, rice wax, wax, montan wax, osikelite, ceresin wax, No9 rough-in wax, and microcrystalline wax. There's wax. Synthetic waxes include low molecular weight polyolefins such as low molecular weight polyethylene, polyzolopyrene, ethylene/vinyl acetate copolymer, ethylene/acrylic acid copolymer, ethylene oxide, and organic acid (for example, unsaturated carganic acid) glycopolyethylene. These include homopolymers and copolymers of these systems, their oxides, halides, saponified products, etc., low molecular weight polyamides, polyesters, etc., and fatty acid waxes and derivatives thereof. As the binder resin other than thermoplastic rubber and wax-like substances, conventionally known resins can be used as binder resins for toner. Among thermoplastic rubbers, those mentioned as hard components of block or ground copolymers are examples.
1. The toner of the present invention may contain a magnetic material in order to be used in a -component development method or the like. The amount of magnetic powder in the toner varies depending on conditions such as the developing process, but is usually used in an amount of about 2 to 1 times the total weight of the N-binding resin. The magnetic properties of the toner include saturation magnetization of 3θ to 60 em
U/, S+ level is easy to use. Magnetic materials include iron,
Metals such as cobalt and nickel, their derivatives, and their derivatives are used. For magnetic developer, /'m5
On, γ-F'a20a, cobalt-doped iron oxide, and ferrite powders such as MnZn 7 elite and NiZn ferrite are often used.

These magnetic powders may be either granular powder or acicular powder depending on the purpose, and those having a particle size of about θ0/~aμ are easy to use. These magnetic powders usually have a hydrophilic surface and have poor affinity with the binder resin. Therefore, in order to improve the affinity with the binder resin and the electrical properties and mechanical properties of the toner, the surface of the magnetic powder is coated with long-chain fatty acids such as stearic acid, polar groups such as -OH groups, -COOH groups, etc. It may be used after being treated with a resin-like material having a group, or a silane thread, a titanate-based coupling agent, or the like. These toners containing a magnetic substance can also be used to develop a magnetic latent image instead of an electrical latent image, if necessary.

In addition, conventionally known coloring agents include carbon black, magenta, yellow, and various cyan pigments, nigrosine,
You can use various dyes such as Asto Blue and other sublimation dyes.

In addition to this, other resinous additives may be added to the toner as necessary.
Plasticizers, granular or fibrous organic and inorganic reinforcing brightening agents, extender pigments not intended for coloring, antioxidants, foaming agents, conductive or charge control agents, ionic and nonionic surfactants, etc. It is also possible to include

Furthermore, in order to more than improve the fluidity, development, transferability, and storage stability of toner particles, or to prevent toner filming on the surface of a photoconductor, and to improve toner cleanability. External additives may also be used in combination with the toner particles to enhance the toner particles. External additives include long chain fatty acids such as stearic acid and their esters, amides, metal salts, binary molybdenum, carbine black, graphite, fluorocarbon graphite, silicon carbide, boron nitride, hexaphosphoric acid, and There are fine powders of aluminum, titanium dioxide, zinc oxide, etc., fluorine resin powders, etc. These external additives usually have a critical surface tension of 30 d
These are homogeneous fine particles having a low surface energy of yn /di or less, or having a smooth surface with a friction coefficient of θ/ or less, or fine particles having non-adhesiveness and some abrasiveness.

Furthermore, if necessary, these external additives may be fixed on the toner surface using hot air or the like.

The toner of the present invention has particular significance when manufactured by the cross-wire pulverization method, but it may be manufactured by any other manufacturing method such as the men-o-ray drying method.
In either case, sufficiently good pressure fixing properties, blocking resistance, impact resistance, and powder fluidity are guaranteed.

Furthermore, the toner of the present invention is fixed at a surface pressure of about 20θ at 9/d.
It is not necessary to perform pressure fixing only with the pressure fixing device of i, but sufficient fixing performance can be achieved with pressure fixing devices with other surface pressures. Furthermore, if there is a fixing device that uses pressure during fixing, such as a fixing device that uses both heat and pressure, its characteristics will be exhibited and sufficient fixing performance will be guaranteed. Furthermore, it is possible to sufficiently fix the image by using heat or a solvent without using pressure.

EXAMPLES The present invention will be explained below with reference to Examples, but it goes without saying that the present invention is not limited to these Examples.

The composition ratios of Examples 1 and 2 were systematically changed and melt-kneaded for S minutes in a straight mixer. The composition of the toner is TR-//θ7, with the amount of magnetite fixed at 50 parts by weight relative to 700 parts by weight of the toner.

The amount of Sunwax E-300 and Sunwax E-300 is 0.0. ! ;1/θ15, θ2S13θ
, and s, 10.15', θ, ko,! −, 3θ,
3sXtto capacitance part. Capacity part is polystyrene resin, TR-//θ resin, Sunwax E 30
0, and the apparent specific gravity of magnetite is lO! ;, 0
．． Calculate as 9'l, θwa3, and fO. /
The table results are as shown in Table 1. Those marked with X showed insufficient melting of the resin, resulting in a rating of 6, and those marked with XX had a particularly pronounced tendency of number 7.

The mixed material was coarsely pulverized in a nommer mill and then pulverized in a jet mill. The results are also shown in Table 7. ΔΔ
Those marked with a mark had an average particle size of 30μ or more, and those with a Δ mark had an average particle size of 20 to 30μ. For those pulverized to 30 μ or less, the average particle size is /9 using a wind classifier.
-/Aμ, and then θ to 10θ weight part of toner.
Car yj in the weight department? Black was added externally to the Henschel mixer.

The Vlt00 measurement values of the toners obtained in this way are shown in Table 1.The electrical resistivity of these toners is approximately SOθ
After pressure molding at a pressure of #/cnl, g K V / Cr
When measured with an electric field of n, both /θ14~/θ1
It was sΩα.

On the other hand, a one-component developer and a pressure fixing device (surface pressure approx./gθ) were installed in F-Me 2300 manufactured by Fuji Xerox Co., Ltd., and the toner obtained as described above was developed and transferred to plain paper. , and the pressure fixing properties and other aspects of each toner were evaluated. The results are shown in Table 3.

Table 3 In Table 3, / indicates that the material was not sufficiently pressure-sensitively deformed and was not fixed, and 2 indicates that it was not fixed.
The image was fixed, but the image intensity was weak or dark (@ indicates a tendency for the image intensity to be weak); 3: the image was fixed, but the image tended to peel off easily; DA: powder The fluidity was extremely poor, - The toner could not be sufficiently conveyed onto the sleeve of the component developer, and S was the one that caused the toner to solidify in the component developer @ during evaluation under a high temperature range of 35°C. , are shown respectively. Products without numbers showed good results in terms of fixing properties, powder fluidity, and anti-blocking properties, and even after continuous copying of 10 kc, there was no change in image quality and high-quality images were obtained. Ta. It can be considered that the photoreceptor is not contaminated by toner or the like.

According to the above results, in the toner 1θ volume part, TR//θ7, that is, thermoplastic rubber, is added to 20 parts by volume, and Sunwax E is added.
-3θO, that is, when containing a wax-like substance /S to 3S volume parts, and the sum of TR//θ7 and sunwax E-3θθ is 2s to 3S volume parts, V2O0 has a value of /Otsu or less. It can be seen that a toner with good pressure fixability, excellent manufacturability, powder fluidity, blocking resistance, and impact resistance can be obtained.

The composition ratios of the Examples were systematically changed, and the compositions were melt-kneaded using an extruder-type continuous mixer. The composition is the toner 10θ, and the pulp t -da and high wax '
The amounts of I; 102E were made to be 6, /2, / g% Koda and 101.20, 30, G O volume parts, respectively. Cargin black was fixed to the S capacity section. The volume part is styrene-butyl methacrylic V-) gM combined tree) lit
, Tsurprene T-G/4t1 Hiwax'12θ2
E, the apparent specific gravity of Kargan Black is 10 each! ;,
It was calculated by assuming that θ9S1θ9'l, Ig. The results are shown in Table 9.

The mixed wires (those other than XX and

The results are shown in Table 7. The meaning of the symbol is the same as in the case of -/.

The particles were crushed to 30μ or less using an air classifier to adjust the average particle size to /lI~/Aμ, and 63 parts by weight of polyfluorhipinylidene fine particles were added to a blender based on 700 parts by weight of the toner. and mixed to obtain a toner. The measured value of V3O0 of the toner obtained in this way was
Shown in the table.

Table 5 A pressure fixing device (surface pressure, approx. 2!; O#/cnt) was installed in a Fuji Xerox Co., Ltd. ffF Meco 3θ0, and the toner obtained as described above was transferred to a carrier (F Me-2300).
Transfer the image to plain paper using a developer mixed with 2 parts of monomer to 2 parts of θOM (for /θθμ resin coat carrier),
After fixing, the pressure fixing properties and other aspects of each toner were evaluated.

The results are shown in Table 6.

Part 2 The meanings of the numbers are the same as in Example -/.

Products without a number showed good results in terms of fixing properties, powder fluidity, and anti-blocking properties, and did not cause fluctuations in image quality even after continuous copying of 10kc, resulting in high-quality images. Ta.

From the above results and the results of Examples/Example/1, regardless of the presence or absence of magnetic powder and its content, 6 to 20 parts by volume of thermoplastic rubber and a wax-like substance/S/S in the toner/θO container.
~3S parts by volume, and when the sum of the thermoplastic rubber and waxy material is 23-'Is parts by volume, V2O0 is 76
% or less, indicating that a toner with good pressure fixing properties and excellent # building properties, powder fluidity, blocking resistance, and impact resistance can be obtained.

'1゜

Claims (1)

[Claims] Toner/θOW ft contains 6 to -0 volume parts of thermoplastic rubber and S to 3S volume parts of waxy substance, and the sum of the thermoplastic rubber and waxy substance is 2.5' to 'I
! ; A pressure fixing toner characterized by being a capacitive part.