JP4090025B2 - Powder flowability evaluation apparatus, electrostatic charge image developing toner, image forming method, and toner cartridge - Google Patents

Description

【０１３６】
以上の結果から分かるように、トナー粉体相の本発明の評価装置による流動性評価値とドット再現性との間には強い相関関係が存在し、本発明の評価装置によりドット再現性を評価できることが分かる。また、ドット再現性の良い高画質を得るために必要な、流動性の良いトナーを得るためには、以下の条件を満足することが必要である。
▲１▼ 円錐ロータ侵入時のトルクの値が０．１〜８．３ｍＮｍである。
▲２▼ 円錐ロータ侵入時の荷重の値が０．０１〜１．１４Ｎである。
【０１３７】
円錐ロータ侵入時のトルク値が０．１ｍＮｍ未満では、トナーの流動性以外の帯電特性が悪くなり画質低下が生じ、８．３ｍＮｍより大きくなれば流動性が低下し、ドット再現性が悪くなる。円錐ロータ侵入時の荷重値が０．０１Ｎ未満では、トナーの帯電特性が悪くなり画質低下が生じ、１．１４Ｎより大きくなるとトナーの流動性が低下しドット再現性が悪くなる。
【０１３８】
【発明の効果】
（１）請求項１〜９の粉体流動性評価装置によれば、粉体相の高さを計測して圧密状態を評価した後、粉体相中に円錐ロータを回転させながら侵入させ、円錐ロータが粉体相中を移動するときに発生するトルクまたは荷重を測定することにより、粉体の流動性が精度良く、個人差の無い評価ができるようになる。
【０１３９】
（２）請求項９に記載の静電荷像現像用トナーの製造方法によれば、粉体流動性評価装置で高画質の得られるトナーを規定するので、高画質が得られる。
【図面の簡単な説明】
【図１】本発明の粉体流動性評価装置の一例を示す概略構成図である。
【図２】（ａ）は円錐ロータの断面図、（ｂ）はその平面図である。
【図３】（ａ）（ｂ）は他の円錐ロータの形状を示す平面図、（ｃ）は断面図である。
【図４】実施例１〜１５の円錐ロータ侵入時のトルクとドット再現性との関係をグラフ化したものである。
【図５】実施例１〜１５の円錐ロータ侵入時の荷重とドット再現性との関係をグラフ化したものである。
【図６】本発明の評価装置をトナー製造過程で用いたトナー製造装置の例を示す概略図である。
【図７】本発明の評価装置を用いて製造したトナーを使用した現像装置の例を示す概略図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for evaluating the fluidity of powder, a toner for developing an electrostatic image produced using the apparatus, a developing method using the toner, and a toner cartridge containing the toner.
[0002]
[Prior art]
Electrophotographic copying machines and printers have been improved in image quality, and fine dot reproducibility has become very important recently. The dot reproducibility is greatly influenced by the fluidity in addition to the charge amount of toner and developer, and it is necessary to stably transport and supply a uniform toner layer or developer layer to a fine latent image portion. It is. Further, as the image quality is improved, the toner used in the toner is becoming smaller in size and higher in function. Therefore, the structure of the toner has become complicated, and finer control at the time of toner production has become necessary than before. In particular, since the fluidity of toner affects various image qualities in addition to dot reproducibility, there is a need for a highly accurate evaluation method with no individual differences in terms of evaluation.
[0003]
In addition, when the toner production method changes from the pulverization method to another method such as a polymerization method, the change in the flow characteristics with respect to the production conditions is large, and compared with the pulverization method, the finer toner production method. Control and evaluation are needed. Furthermore, the fluidity of the toner needs to be in a stable state with little change even if mechanical addition is applied in the apparatus. However, there is no method that can accurately evaluate it, and a new evaluation method is required. It has become.
[0004]
For example, there is known a method for accurately evaluating the fluidity of a developer in a developing machine by measuring the time required to drop through a narrow portion of a funnel to which a magnetic field is applied (for example, patents). Reference 1 etc.). In addition, a method is known in which toner is placed on a tiltable plate, the plate is gradually tilted, and the angle when the flow starts and when the flow ends is measured (for example, see Patent Document 2). Further, the sieves are stacked in several stages, and the toner is put on the sieves, and vibrations in the horizontal direction and the vertical direction are given to the sieve parts. The amount of toner remaining in each sieve part after a predetermined time is preset. A method of calculating by multiplying by a coefficient is known (see, for example, Patent Document 3). However, all of these methods have large variations in data, and there are differences depending on the measurer, and it has not been possible to evaluate the difference in fluidity between fine toners.
[0005]
[Patent Document 1]
JP-A-2-203941
[Patent Document 2]
JP-A-4-116449
[Patent Document 3]
JP 2000-292967 A
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above background, and has developed a method for evaluating the fluidity of powder (for example, toner) with high accuracy and no individual difference, and by using this method, An object of the present invention is to obtain a toner for developing an electrostatic charge image which has good dot reproducibility and can stably obtain high image quality.
[0007]
[Means for Solving the Problems]
As a result of repeated studies to achieve the above problems, the present inventors have previously determined the fluidity of the powder. Stabilized by shaker Powder phase Amount of change from reference height When Powder By quantitatively measuring the torque or load generated when the conical rotor moves through the powder phase after evaluating the compaction state from the weight information and allowing the conical rotor to enter the powder phase while rotating. In addition, it was confirmed that it was possible to evaluate accurately and without individual differences, and that the fluidity difference between fine powders could be accurately evaluated. The present invention has been made based on this.
According to the present invention, the following (1) to ( 9 ) Is provided.
[0008]
(1) An apparatus for evaluating the fluidity of powder by allowing the conical rotor to enter the powder phase while rotating, and measuring the torque or load generated when the conical rotor moves in the powder phase. In the powder phase Change from the reference height Means of measuring And a vibrator provided under a container for storing powder With The state of the powder phase is stabilized by the vibrator, and then the amount of change from the reference height of the powder phase is measured. Powder phase Amount of change from reference height An apparatus for evaluating the fluidity of a powder, wherein a torque or a load generated when the conical rotor moves in the powder phase is measured after evaluating the compacted state from the weight information.
[0009]
(2) In the powder fluidity evaluation apparatus described in (1) above, after measuring the height of the powder phase in advance, the cone rotor is allowed to enter while rotating the cone rotor, An apparatus for evaluating the fluidity of a powder, characterized by measuring a torque or a load generated when moving in a phase.
[0010]
(3) The powder fluidity evaluation apparatus according to (1) or (2), wherein the powder phase has a height of 5 to 50 mm.
[0011]
(4) The powder fluidity evaluation apparatus according to any one of (1) to (3), wherein the apex angle of the conical rotor is 20 to 150 °. .
[0012]
(5) The powder fluidity evaluation apparatus according to any one of (1) to (4) above, wherein a groove is cut on a surface of the conical rotor.
[0013]
(6) The powder fluidity evaluation apparatus according to any one of (1) to (5), wherein the rotational speed of the conical rotor is 0.1 to 100 rpm. apparatus.
[0014]
(7) The powder fluidity evaluation apparatus according to any one of (1) to (6), wherein the penetration speed of the conical rotor is 0.5 to 150 mm / min. Evaluation device.
[0016]
(8) Above (1) ~ (7) The powder fluidity evaluation apparatus according to any one of the above, wherein the powder phase has a porosity of 0.4 to 0.7.
[0024]
(9) An electrostatic charge image characterized in that evaluation is performed in a toner production process using the powder fluidity evaluation apparatus according to any one of (1) to (8), and toner is produced based on the evaluation. A method for producing a developing toner.
[0030]
As described above, in the present invention, the fluidity of the fluid is measured in advance by measuring the height of the powder phase, recognizing the compaction state, and when the conical rotor moves in the compaction state of the powder phase and the powder phase. In order to measure the relationship between torque or load generated in the powder, it is possible to accurately evaluate the difference between the powder and other powders. In addition, since this method can measure the powder phase as it is in a short time, it can be introduced into the production line and can stably produce high-quality powder.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
The present invention is described in further detail below.
The powder fluidity evaluation apparatus of the present invention measures the height of the powder phase and recognizes the compacted state, and then enters (lowers) or pulls out while rotating the conical rotor into the powder phase. The torque and load applied to the container containing the conical rotor and the powder phase at that time are measured, and the fluidity of the powder is evaluated based on the torque and load values. In the present invention, after measuring the height of the powder phase, a conical rotor is inserted into the powder phase to measure torque and load.
[0032]
The conical rotor may have any shape, but a conical rotor having an apex angle of 20 to 150 ° is suitable. When the apex angle of the cone is smaller than 20 °, the resistance to the powder phase is small, so that the torque and load are small, and it is difficult to evaluate the difference in fine fluidity. On the other hand, when the apex angle is larger than 150 °, the force in the direction of pressing the powder phase becomes large and the powder particles are likely to be deformed, which is not necessarily suitable for evaluating the fluidity of the powder. . The length of the conical rotor needs to be long enough so that the conical rotor surface is continuously present in the powder phase.
[0033]
Moreover, it is better that the conical rotor surface has grooves. Rather than measuring the friction component between the material surface of the conical rotor and the powder particles, it is better to measure the friction component between the powder particles and the powder particles. For this purpose, when the conical rotor rotates and enters the powder phase, the powder particles enter the grooves cut on the surface of the conical rotor, and the entrained powder particles and the surrounding It is more appropriate to measure the friction state with the powder particles. The shape of the groove is not limited, but it is necessary to devise so that the contact between the material surface of the conical rotor and the powder particles becomes small. An example is shown in FIG.
[0034]
This is a groove cut straight from the apex of the cone in the direction of the base, and the cross section of the groove has a sawtooth shape consisting of triangular irregularities. In this case, the contact between the conical rotor material surface and the powder particles is only at the tip of the triangular groove crest. Most of the contact is between the powder particles that have entered the groove and the surrounding powder particles. Any material can be used for the conical rotor, but a material that is easy to process, has a hard surface, and does not change quality is preferable. A material that is not charged is suitable. Examples of this are SUS, Al, Cu, Au, Ag, brass, and the like.
[0035]
The torque and load of the powder vary depending on the rotational speed of the conical rotor and the penetration speed of the conical rotor. In this measurement, in order to improve the measurement accuracy, the rotation speed and penetration speed of the conical rotor are lowered so that the delicate contact state between the powder particles can be measured. Therefore, the measurement conditions were as follows.
・ Rotation speed of conical rotor: 0.1 to 100 rpm
・ Penetration speed of conical rotor: 0.5 to 150 mm / min
[0036]
If the rotational speed of the conical rotor is smaller than 0.1 rpm, it is likely to be affected by the subtle state of the powder phase, which causes a problem of torque measurement variation and may not be suitable for measurement. On the other hand, if it is greater than 100 rpm, powder scattering may occur, and stable measurement may not be possible.
When the penetration speed of the conical rotor is slower than 0.5 mm / min, it is likely to be affected by the delicate state of the powder phase, which may cause measurement variation problems, and may not be suitable for measurement. When it is faster than 150 mm / min, the powder phase tends to be in a compacted state, and influences such as deformation of the powder particles come out, which may not be suitable for fluidity evaluation.
[0037]
The apparatus configuration is as shown in FIG. 1, and is composed of a height measurement zone and a measurement zone. The height measurement zone includes a container (sample container) in which powder is placed, an elevating stage for moving the container up and down, a height measuring means using a laser, a load cell, and the like. In addition, this structure is an example and does not limit this invention. In this configuration, the sample container containing the powder is raised, the surface of the powder is irradiated with laser, and the amount of change from the reference height is measured based on the reflected light information. In addition, the weight of the powder is measured using a load cell at the bottom of the sample container, and the compaction state of the powder phase is evaluated from the height information and weight information of the powder phase. Although not shown, the calculation of these information is performed using a personal computer, for example.
[0038]
The measurement zone is as shown in FIG. 1, and includes a container for storing powder, an elevating stage for moving the container up and down, a load cell for measuring the load, a torque meter for measuring the torque of the powder, and the like. In addition, this structure is an example and does not limit this invention. A conical rotor is attached to the tip of the shaft, and the shaft itself is fixed (with respect to vertical movement). The sample container stage containing the powder can be moved up and down by an elevator, the container containing the powder is placed in the center of the stage, and when the container is raised, the conical rotor rotates and enters the center of the container. Try to do it. Torque applied to the conical rotor is detected by a torque meter at the top, and a load applied to a container containing powder is detected by a load cell under the container. The amount of movement of the conical rotor is determined by a position detector. This configuration is an example, and other configurations such as moving the shaft up and down by an elevator may be used.
[0039]
The shape of the conical rotor is preferably such that the apex angle is 20 to 150 ° as described above (see FIG. 2). The length of the conical rotor needs to be long so that the conical rotor portion can sufficiently enter the powder phase. The shape of the groove may be any shape, but care must be taken so that torque and load values are not reproduced due to the replacement of the conical rotor. For this purpose, the groove shape of the conical rotor is simple, and it is better that the rotor having the same shape can be formed any number of times (see FIG. 3).
[0040]
The material of the container is not limited, but a conductive material is suitable so as not to be affected by charging with the powder. In addition, since the measurement is performed while changing the powder, it is preferable that the surface is close to a mirror surface in order to reduce dirt. The size of the container is important, and it is necessary to select a larger (diameter) size relative to the diameter of the conical rotor so that the wall of the container is not affected when the conical rotor enters while rotating.
[0041]
The torque meter is preferably a high-sensitivity type, and a non-contact type is suitable. A load cell with a wide load range and high resolution is suitable. The position detector includes a linear scale, a displacement sensor using light, etc., but the specification of 0.1 mm or less is suitable for accuracy. The elevator can be driven with high accuracy using a servo motor or a stepping motor.
[0042]
For measurement, a certain amount of powder is put into a container and set in this apparatus. Thereafter, the elevating stage is raised in the height measurement zone, the surface of the powder is irradiated with a laser, and the height of the powder phase is measured. There are various methods for measuring the height of the powder, but there is a method using triangulation as an example. This method irradiates the powder surface with laser and detects the position of the diffuse reflected light from the powder surface to check the displacement. The position of the diffuse reflected light changes as the height position of the laser irradiated surface changes. This is performed by using a CCD or the like that can detect a detailed positional change in the light receiving portion. As the height detection accuracy, an accuracy of 0.1 mm or less is required. Further, the weight of the powder phase is measured with a load cell or the like under the container, and the compacted state is evaluated together with the height information of the powder phase. After measurement, lower the container and return it to its original position.
[0043]
Then, the container containing the powder whose compaction state has been measured is placed on the lifting stage in the measurement zone. This operation may be moved from the height measurement zone to the measurement zone by rotating the elevating stage. Subsequently, the conical rotor is rotated to enter the powder phase in the sample container. When entering torque or load measurement, it is performed at the determined rotation speed and penetration speed. The rotational direction of the conical rotor is arbitrary. If the penetration distance of the conical rotor is shallow, the values of torque and load are small, and problems arise in data reproducibility. Therefore, it is better to penetrate the conical rotor deeply into a region where data reproducibility is present. As a result of our experiment, almost stable measurement was possible by intruding 5 mm or more.
[0044]
The measurement mode can be performed under any conditions, but examples include the following measurement modes.
(1) Fill the container with powder.
(2) The compacted state is evaluated from the height measurement and load measurement of the powder phase.
(3) Insert the conical rotor while rotating it, and measure the torque and load at that time.
(4) When the conical rotor enters from the toner surface layer to a preset depth, the intrusion operation is stopped.
(5) Start the operation of pulling out the conical rotor.
(6) When the tip of the conical rotor comes off from the powder phase surface and becomes completely free (first home position), the conical rotor pulling operation is stopped and the rotation is also stopped.
Measurement is carried out by repeating the above operations (1) to (6). It may be performed continuously.
[0045]
As another measurement method, the powder phase is stabilized by applying vibration with a vibrator (see FIG. 1) before height measurement, and the stabilized powder phase is irradiated with a laser to obtain powder. The phase height is measured, the powder weight is measured, and the compacted state is determined (evaluated) from these. The conical rotor is inserted while rotating into the powder phase whose compaction state has been evaluated, and the torque and load at that time are measured. When reaching a preset depth, the intrusion operation is stopped, and then the conical rotor is moved to the initial position ( Up to home position). This measurement may be performed once, but it is also effective to obtain this average torque and load by repeating this operation.
As another method, there is a method in which a conical rotor is inserted into a powder phase whose compacted state has been evaluated, and a depth until reaching a preset torque value is examined.
[0046]
As a method for evaluating the consolidated state, there is a method of calculating a space ratio. In this measurement method, the porosity of the powder phase becomes important, and in our experimental results, stable measurement was possible when the porosity was 0.4 or more. If it is less than 0.4, a subtle difference in the compacted state affects the torque and load, and stable measurement is difficult. The range of the space ratio of the powder phase was 0.4 to 0.7 including the cases of various measurement methods. If it is larger than 0.7, the powder is scattered and is not suitable for measurement. However, the measurement system and measurement conditions are not limited to this.
[0047]
In the powder fluidity evaluation apparatus according to the present invention, the change in the torque your load with respect to the space ratio is examined, and in addition to the evaluation of the fluidity itself, the stability and margin of fluidity are evaluated. When the powder in the evaluation apparatus of the present invention is an electrostatic image developing toner used in an image forming method typified by electrophotography or the like, this toner is an average of toner in order to realize a high-quality image. The particle size needs to be 4 to 10 μm.
The toner has a weight average particle size of 4 to 10 μm, more preferably 5 to 7 μm. If the weight average particle diameter is less than 4 μm, problems such as contamination in the machine due to toner scattering during long-term use, image density reduction in a low-humidity environment, and poor photoconductor cleaning are likely to occur, and there is a concern about the effect on the human body. When the weight average particle size exceeds 10 μm, the resolution of fine spots of 100 μm or less is not sufficient, and the image quality tends to be inferior due to many scattering to non-image areas.
[0048]
The developer using this toner needs to have an average particle diameter of the carrier of 20 to 100 μm in order to realize a high quality image. When the average particle diameter of the carrier is in the range of 20 to 100 μm, the charge amount of the toner can be made more uniform when the toner concentration in the developing machine is in the range of 2 to 10% by weight. When it is smaller than 20 μm, carrier particles are likely to adhere to the photoreceptor, and the stirring efficiency with the toner is deteriorated, so that it is difficult to obtain a uniform charge amount of the toner. On the other hand, when the average particle diameter of the carrier exceeds 100 μm, fine image reproducibility deteriorates and high image quality cannot be obtained.
[0049]
Details of the toner and developer are shown below.
The toner contains at least a colorant and a resin (binder resin) as main components.
As resins, polystyrene resin, epoxy resin, polyester resin, polyamide resin, styrene acrylic resin, styrene methacrylate resin, polyurethane resin, vinyl resin, polyolefin resin, styrene butadiene resin, phenol resin, polyethylene resin, silicon resin, butyral resin, terpene There are resins, polyol resins and the like.
[0050]
Examples of vinyl resins include styrene such as polystyrene, poly-p-chlorostyrene, and polyvinyltoluene, and homopolymers thereof: styrene-p-chlorostyrene copolymer, styrene-propylene copolymer, styrene-vinyltoluene copolymer. Polymer, styrene-vinyl naphthalene copolymer, styrene-methyl acrylate copolymer, styrene-ethyl acrylate copolymer, styrene-butyl acrylate copolymer, styrene-octyl acrylate copolymer, styrene-methacrylic copolymer Acid methyl copolymer, styrene-ethyl methacrylate copolymer, styrene-butyl methacrylate copolymer, styrene-α-chloromethyl methacrylate copolymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer Coalescence, styrene-vinyl ethyl acetate Copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, styrene-acrylonitrile-indene copolymer, styrene-maleic acid copolymer, styrene-maleic acid ester Styrene copolymers such as copolymers: polymethyl methacrylate, polybutyl methacrylate, polyvinyl chloride, polyvinyl acetate and the like.
[0051]
The polyester resin is composed of a dihydric alcohol as shown in the following group A and a dibasic acid salt as shown in the group B, and further a trihydric or higher alcohol as shown in the group C or Carboxylic acid may be added as a third component.
[0052]
Group A: ethylene glycol, triethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,4-butanediol, neopentyl glycol, 1,4 butenediol, 1,4-bis (hydroxymethyl) Cyclohexane, bisphenol A, hydrogenated bisphenol A, polyoxyethylenated bisphenol A, polyoxypropylene (2,2) -2,2′-bis (4-hydroxyphenyl) propane, polyoxypropylene (3,3) -2 , 2-bis (4-hydroxyphenyl) propane, polyoxyethylene (2,0) -2,2-bis (4-hydroxyphenyl) propane, polyoxypropylene (2,0) -2,2′-bis ( 4-hydroxyphenyl) propane and the like.
[0053]
Group B: maleic acid, fumaric acid, mesaconic acid, citraconic acid, itaconic acid, glutaconic acid, phthalic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, succinic acid, adipic acid, sebacic acid, malonic acid, linolenic acid, or These acid anhydrides or esters of lower alcohols.
[0054]
Group C: Trivalent or higher alcohols such as glycerin, trimethylolpropane and pentaerythritol, and trivalent or higher carboxylic acids such as trimellitic acid and pyromellitic acid.
[0055]
As the polyol resin, an alkylene oxide adduct of an epoxy resin and a dihydric phenol, or a compound having one active hydrogen in the molecule that reacts with the glycidyl ether and the epoxy group, and an active hydrogen that reacts with the epoxy resin in the molecule. There are those obtained by reacting two or more compounds.
[0056]
The following are used as the pigment used in the present invention.
[0057]
Examples of black pigments include azine dyes such as carbon black, oil furnace black, channel black, lamp black, acetylene black, and aniline black, metal salt azo dyes, metal oxides, and composite metal oxides.
[0058]
Examples of yellow pigments include cadmium yellow, mineral fast yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa yellow G, Hansa yellow 10G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, and tartrazine lake. .
[0059]
Examples of the orange pigment include molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, and indanthrene brilliant orange GK.
[0060]
Examples of red pigments include Bengala, Cadmium Red, Permanent Red 4R, Resol Red, Pyrazolone Red, Watching Red Calcium Salt, Lake Red D, Brilliant Carmine 6B, Eosin Lake, Rhodamine Lake B, Alizarin Lake, Brilliant Carmine 3B.
[0061]
Examples of purple pigments include fast violet B and methyl violet lake.
[0062]
Examples of blue pigments include cobalt blue, alkali blue, Victoria blue lake, phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partially chlorinated, first sky blue, and indanthrene blue BC.
[0063]
Examples of green pigments include chrome green, chromium oxide, pigment green B, and malachite green lake.
[0064]
These can use 1 type (s) or 2 or more types.
Particularly in color toners, uniform dispersion of good pigments is essential, and instead of putting the pigments directly into a large amount of resin, a master batch in which the pigments are once dispersed at a high concentration is manufactured and diluted. The method of throwing in is used. In this case, a solvent is generally used to assist dispersibility. However, there is a problem of environment and the like, and in the present invention, water is used for dispersion. When water is used, temperature control is important so that residual moisture in the masterbatch does not become a problem.
[0065]
In the toner of the present invention, a charge control agent is blended (internally added) inside the toner particles. However, it may be used by mixing (external addition) with toner particles. The charge control agent makes it possible to control the optimum charge amount according to the development system. In particular, in the present invention, the balance between the particle size distribution and the charge amount can be further stabilized.
[0066]
For controlling the toner to be positively charged, nigrosine and quaternary ammonium salts, triphenylmethane dyes, imidazole metal complexes and salts can be used alone or in combination of two or more. Further, salicylic acid metal complexes, salts, organic boron salts, calixarene compounds, and the like are used for controlling the toner to be negatively charged.
[0067]
Further, a release agent can be internally added to the toner in the present invention to prevent offset at the time of fixing.
Release agents include natural waxes such as candelilla wax, carnauba wax, rice wax, montan wax and derivatives thereof, paraffin wax and derivatives thereof, polyolefin wax and derivatives thereof, sazol wax, low molecular weight polyethylene, and low molecular weight polypropylene. And alkyl phosphate esters.
The melting point of these release agents is preferably 65 to 90 ° C. When the temperature is lower than this range, blocking during storage of the toner tends to occur, and when the temperature is higher than this range, an offset is likely to occur in a region where the fixing roller temperature is low.
[0068]
Additives may be added for the purpose of improving the dispersibility of a release agent or the like. As additives, styrene acrylic resin, polyethylene resin, polystyrene resin, epoxy resin, polyester resin, polyamide resin, styrene methacrylate resin, polyurethane resin, vinyl resin, polyolefin resin, styrene butadiene resin, phenol resin, butyral resin, terpene resin, There is a polyol resin or the like, and a mixture of two or more of these resins may be used.
[0069]
There are several methods for producing the toner according to the present invention, but the pulverization method will be described as an example. First, the resin, the pigment or dye as the colorant, the charge control agent, the release agent, and other additives. Are sufficiently mixed with a mixer such as a Henschel mixer, and then used as a constituent material using a thermal kneader such as a batch-type two-roll, Banbury mixer, continuous twin-screw extruder, or continuous single-screw kneader. Are kneaded well, and after rolling and cooling, cutting is performed. The toner kneaded product after cutting is crushed, coarsely pulverized using a hammer mill, etc., and further pulverized by a fine pulverizer or mechanical pulverizer using a jet stream, and a classifier or Coanda effect using a swirling airflow Is classified to a predetermined particle size by a classifier using Thereafter, an additive composed of inorganic particles or the like is adhered or fixed to the particle surface by a mixer.
[0070]
The fluidity of the toner particles after this mixing step is evaluated using this evaluation apparatus. In this case, in the sampling inspection, a sample is put in a sample container, the sample container is directly placed on the sample stage of the evaluation apparatus shown in FIG. 1, and the measurement is performed after the toner powder phase is consolidated. The rotational speed of the conical rotor was 0.1 to 100 rpm, and the penetration speed of the conical rotor was 0.5 to 100 mm / min. In the measurement, the conical rotor is rotated while entering, and after a predetermined intrusion distance of 5 mm or more, the intrusion is stopped, and then the conical rotor is pulled out and returned to the original initial position. The torque and load when the conical rotor enters the toner powder phase are measured to evaluate the toner fluidity.
[0071]
When the powder fluidity is evaluated by the powder fluidity evaluation apparatus of the present invention, the measured value (torque, load) and the toner fluidity have the following relationship.
・ When torque is small, fluidity is good.
・ If the torque is large, the fluidity is poor.
-When the load is small, the fluidity is good.
・ If the load is large, the fluidity is poor.
[0072]
Further, the change in measured values (torque, load) with respect to the space ratio measured by the toner fluidity evaluation apparatus of the present invention and the stability of toner fluidity have the following relationship.
・ The stability of fluidity is good when the slope of the space factor-torque characteristic is small.
• If the slope of the space factor-torque characteristic is large, the fluidity stability is poor.
-If the slope of the space factor-load characteristic is small, the fluidity is stable.
• If the slope of the space factor-load characteristic is large, the fluidity stability is poor.
[0073]
The characteristics of the evaluation apparatus of the present invention using the conical rotor are as follows (1), (2), (3), and (4), and the sample sample can be measured quickly and easily without any individual differences. It is to be able to measure with high accuracy.
(1) Non-destructive inspection.
(2) The sample can be measured as it is.
(3) It can be measured in a short time.
(4) Anyone can easily measure.
[0074]
Therefore, measurement on the production line is also possible, and it can be installed between each process in the production process to evaluate the quality during the process. For example, after passing through the mixing step, a sample extraction / measurement zone is provided in the middle of conveying the powder sample to the next step, and a shutter is opened and closed at a certain timing to convey a certain amount of sample to the measurement unit. The tip of the measurement part is a container made of SUS or the like, and is directly measured by the evaluation apparatus of the present invention. Alternatively, the container is taken to the evaluation apparatus of the present invention in another nearby place, placed on the sample stage, and measured with this evaluation apparatus.
[0075]
After the measurement, the toner is returned to the original sample. As a result of the evaluation, if the numerical value is out of the predetermined setting range, the sample is not sent to the filling process, but is sent to the toner reprocessing process. These mechanisms can be applied to the inspection after the pulverization / classification process, which is the process before the mixing process, the inspection after the air sieving process after the mixing process, the inspection before filling, and the like (see FIG. 6).
It is also possible to independently use a powder fluidity evaluation apparatus having these functions as an evaluation apparatus in the development stage.
[0076]
As described above, the measured values of torque and load in the evaluation apparatus of the present invention indicate fluidity, and quantitative evaluation is possible. The conventional evaluation methods so far can evaluate the difference between powders, but there is a problem that the same soil cannot be evaluated if the types of powders are different. However, the values measured by the evaluation method of the present invention are torque values and load values as powder characteristics, and are values that can be evaluated on the same soil regardless of whether the type of powder changes or the particle size changes. It becomes a general-purpose evaluation value. Moreover, since the difference in fluidity can be evaluated after evaluating the consolidated state, multi-faceted evaluation is possible.
[0077]
The torque and load characteristics during the movement of the conical rotor in the powder phase are closely related to the fluidity of the powder. When the fluidity of the powder is good, it is between each individual powder particle. Since the adhesion force is small, it is easy to move. Even if the conical rotor is moved in the powder phase, the torque is small and the load change is small. However, when the flowability of the powder is poor, the adhesion force between the individual powder particles is large and the movement is difficult, and when the conical rotor is moved within the powder phase, the conical rotor is used. The torque applied to is increased, and the force (load) acting downward is also increased.
[0078]
Therefore, in the evaluation apparatus of the present invention, the fluidity can be evaluated according to the following relationship.
・ When fluidity is good → Torque and load are small when moving in the powder phase.
・ When fluidity is poor → Torque and load are large when moving in the powder phase.
[0079]
The fluidity of the toner is almost determined by the mixing process in the toner manufacturing process. That is, the fluidity of the toner particles varies greatly depending on the state in which the additive composed of inorganic particles adheres to or adheres to the surface of the toner particles.
The mixing state of the toner varies depending on the mixing conditions (amount charged, the number of rotations, a mixing time, etc.) in the mixing step. Therefore, the mixing conditions play an important role in the fluidity, and the evaluation of the fluidity after the mixing process is important.
[0080]
In order to achieve high image quality in printers and copiers, it is necessary to improve the reproducibility of extremely minute dots. In order to realize this, toner development that is faithful to a very small latent image is required. In order to enable this faithful development, it is necessary to supply a uniform toner brush to the development area. For this purpose, it is necessary that the toner charge amount is in an appropriate condition. However, the toner is easy to move and transport so that a uniform toner brush can be constantly supplied to the development area. It becomes important. That is, in order to improve the fine dot reproducibility, it is necessary to increase the fluidity of the toner.
[0081]
Further, the stability of the toner fluidity was evaluated by the evaluation method of the present invention using a conical rotor, and as a result of examining the relationship with the toner transportability of the developing portion during running, a very strong correlation exists, When the slope of the space ratio-torque characteristic and the slope of the space ratio-load characteristic were small, the toner transportability of the toner developing portion during running was good, and problems such as blocking did not occur.
[0082]
From the results, it was found that the toner having stable fluidity exhibits the following space ratio-torque characteristics and space ratio-load characteristics.
(1) The slope of the space factor-torque characteristic when the conical rotor enters (20 mm) is −33 to 0 mNm / ε. (Ε: space ratio)
{Circle around (2)} The slope of the space factor-load characteristic when the conical rotor enters (when 20 mm enters) is −35 to 0 N / ε. (Ε: space ratio)
[0083]
As a method for producing the toner according to the present invention, methods other than the pulverization method are conceivable, and examples of the polymerization methods (suspension polymerization, emulsion polymerization, dispersion polymerization, emulsion aggregation, emulsion association, etc.) include monomers and colorants. Then, the toner composition is obtained by suspending and polymerizing the monomer composition to which the charge control agent and the like are added in an aqueous medium. The granulation method is not particularly limited.
[0084]
For example, in the toner of the present invention, an oily dispersion in which at least a polyester-based prepolymer containing an isocyanate group is dissolved in an organic solvent, a pigment-based colorant is dispersed, and a release agent is dissolved or dispersed in an aqueous medium. A urea-modified polyester resin having a urea group by dispersing in the presence of inorganic fine particles and / or fine polymer particles and reacting the prepolymer with a polyamine and / or a monoamine having an active hydrogen-containing group in the dispersion. And a liquid medium contained in the dispersion containing the urea-modified polyester resin is removed.
[0085]
In the urea-modified polyester resin, the glass transition temperature (Tg) is 40 to 65 ° C, preferably 45 to 60 ° C. The number average molecular weight (Mn) is 2500 to 50000, preferably 2500 to 30000. The weight average molecular weight (Mw) is 10,000 to 500,000, preferably 30,000 to 100,000.
[0086]
This toner contains, as a binder resin, a urea-modified polyester resin having a urea bond that has been increased in molecular weight by the reaction between the prepolymer and the amine. The colorant is highly dispersed in the binder resin.
[0087]
The obtained toner powder after drying is air-classified, and an additive composed of inorganic fine particles or the like is adhered or fixed to the particle surface by a mixer under the optimum mixing conditions. Alternatively, the charge control agent may be applied to the surface of the toner powder after drying and fixedly injected. Further, thereafter, an additive made from inorganic fine particles or the like may be adhered or fixed to the particle surface. By placing the charge control agent on the surface, the charge amount of the toner can be easily controlled.
[0088]
Specific means for mixing and fixing and injecting are as follows: a method of applying an impact force to the powder mixture with blades rotating at high speed; For example, there is a method of causing the particles to collide with an appropriate collision plate. As equipment, Ong mill (manufactured by Hosokawa Micron Co., Ltd.), I-type mill (manufactured by Nippon Pneumatic Co., Ltd.) has been modified to lower the pulverization air pressure, hybridization system (manufactured by Nara Machinery Co., Ltd.), kryptron System (manufactured by Kawasaki Heavy Industries, Ltd.), automatic mortar, etc.
In order to evaluate whether predetermined fluidity is obtained after this mixing process, it evaluates using this evaluation device.
Also in the case of these methods, for inspection after granulation, inspection after treatment with charge control agent, inspection after mixing process of additive, inspection after air sieving process after mixing process, inspection before filling, etc. Applicable.
[0089]
In addition, although the fluidity is affected by the toner shape, in the case of a very spherical toner having an average circularity of 0.9 to 0.99, the fluidity is excellent and the dot reproducibility is excellent. Realization of image quality.
Further, when used as a two-component developer, a two-component developer is obtained by mixing with a magnetic carrier described later at a predetermined mixing ratio.
The toner according to the present invention can also be used as a one-component developer used in a contact or non-contact development system. As the contact or non-contact development method, various known methods are used. For example, there are a contact development method using an aluminum sleeve, a contact development method using a conductive rubber belt, and a non-contact development method using a development sleeve in which a conductive resin layer containing carbon black or the like is formed on the surface of an aluminum base tube. .
[0090]
Further, since the toner of the present invention has excellent fluidity when developed using an AC bias voltage component during development, the toner of the present invention vibrates faithfully according to the electric field, and can faithfully develop fine latent images. Development with good reproducibility is possible.
[0091]
Further, in the one-component development method, the present toner is used in a development method in which a roller-shaped blade for making the toner layer uniform is provided at the outlet of the toner supply unit. In the case of such a system, not only filming on the photoconductor but also filming on the doctor roller occurs. For this reason, the toner layer cannot be formed uniformly, the toner charge becomes non-uniform, and the toner charge amount becomes small. For this reason, poor development occurs.
However, when the toner of the present invention is used, filming on the doctor roller does not occur, stable development is performed, and the system has excellent durability characteristics (see FIG. 7).
[0092]
Further, when the magnetic toner is used, magnetic particles may be internally added to the toner particles. Examples of the magnetic material include ferromagnetic materials such as ferrite, magnetite, iron, nickel, cobalt, and alloys thereof. The average particle size of the magnetic material is preferably 0.1 to 1 μm. The content of the magnetic material is preferably 10 to 70 parts by weight with respect to 100 parts by weight of the toner.
[0093]
As the carrier used in the two-component developer, known carriers can be used. For example, magnetic particles such as iron powder, ferrite powder, nickel powder, magnetite powder, or the surface of these magnetic particles are made of fluorine resin or vinyl resin. And those treated with a silicone-based resin or the like, or magnetic particle-dispersed resin particles in which magnetic particles are dispersed in the resin. The average particle size of these magnetic carriers is preferably 20 to 100 μm. Preferably 20-70 micrometers is good.
[0094]
Further, as described above, the toner according to the present invention can be used by adding inorganic fine powder to the toner as a fluidity improver. The average particle size of the inorganic fine powder is suitably 20 to 200 nm. When the particle diameter is smaller than 20 nm, it is difficult to produce an uneven surface having an effect on fluidity, and when the particle diameter is larger than 200 nm, the powder shape becomes rough, resulting in a problem of toner shape.
[0095]
Inorganic fine powders include oxides such as Si, Ti, Al, Mg, Ca, Sr, Ba, In, Ga, Ni, Mn, W, Fe, Co, Zn, Cr, Mo, Cu, Ag, V, and Zr. And composite oxides. Of these, fine particles of silicon dioxide (silica), titanium dioxide (titania), and alumina are preferably used. Furthermore, it is effective to perform a surface modification treatment with a hydrophobizing agent or the like. Typical examples of the hydrophobizing agent include the following.
[0096]
Dimethyldichlorosilane, trimethylchlorosilane, methyltrichlorosilane, allyldimethyldichlorosilane, allylphenyldichlorosilane, benzyldimethylchlorosilane, bromomethyldimethylchlorosilane, α-chloroethyltrichlorosilane, p-chloroethyltrichlorosilane, Chloromethyldimethylchlorosilane, chloromethyltrichlorosilane, hexaphenyldisilazane, hexatolyldisilazane, etc.
[0097]
The inorganic fine powder is preferably used in an amount of 0.1 to 2% by weight based on the toner. If it is less than 0.1% by weight, the effect of improving toner aggregation is poor, and if it exceeds 2% by weight, problems such as toner scattering between fine wires, contamination in the machine, scratches and abrasion of the photoreceptor tend to occur. is there.
[0098]
Further, a charge control agent may be adhered or fixed to the surface of at least a powder composed of a resin and a pigment so that the powder surface shape has a small period and a large period. The average particle size is optimally as small as 20 to 200 nm. When the particle diameter is smaller than 20 nm, it is difficult to produce an uneven surface having an effect on fluidity, and when the particle diameter is larger than 200 nm, the powder shape becomes rough, resulting in a problem of toner shape. Examples of charge control agents include nigrosine and quaternary ammonium salts, triphenylmethane dyes, imidazole metal complexes and salts, salicylic acid metal complexes and salts, organoboron salts, calixarene compounds, etc. Also good.
[0099]
Further, the developer of the present invention may further contain other additives within a range that does not have a substantial adverse effect, for example, a lubricant powder such as Teflon (R) powder, zinc stearate powder, polyvinylidene fluoride powder; or cerium oxide. Abrasives such as powder, silicon carbide powder and strontium titanate powder; or a conductivity imparting agent such as carbon black powder, zinc oxide powder and tin oxide powder can be used in small amounts as a developability improver.
[0100]
The evaluation apparatus of the present invention can also be used for toners and capsule toners produced by a polymerization method, a spray drying method, etc., which are produced without using a kneading step or a pulverizing step.
[0101]
【Example】
Next, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples. In the examples, all parts represent parts by weight.
[0102]
In the following examples, toners having different toner compositions, toner production methods, and mixing conditions are produced, toner fluidity is evaluated using the evaluation apparatus of the present invention, and dot reproducibility is evaluated on a five-point scale based on the roughness of the image. (Rank 1: bad → rank 5: good).
As for the fluidity of the toner, torque and load values were measured when the conical rotor entered 20 mm from the surface of the toner powder phase at the time of entry.
・ Vertical angle of conical rotor: 50 °
・ Rotation speed of conical rotor: 2rpm
・ Invasion speed of conical rotor: 10 mm / min
[0103]
Example 1
Resin Polyester resin 100 parts
Pigment Copper phthalocyanine blue pigment
(C.I. Pigment Blue 15: 3) 3.5 parts
Charge control agent Zinc salicylate 5 parts
The raw materials were sufficiently mixed with a mixer and then melt kneaded with a twin screw extruder at a barrel temperature of 100 ° C. and a kneader rotation speed of 100 rpm. The kneaded product was rolled and cooled, coarsely pulverized by a cutter mill, pulverized by a fine pulverizer using a jet stream, and then classified into a particle size distribution having an average particle size of 6.5 μm using a swirling air classifier. Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 0.8 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0104]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
The obtained toner was set in a copying machine in which the latent image carrier is an OPC drum photoreceptor and the cleaning method is blade cleaning, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 4 in a 5-level evaluation.
[0105]
(Example 2)
Kneading, pulverization, and classification were performed using the same raw materials and production methods as in Example 1, and the particles were classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0106]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation manufacturing of the present invention, and the results are shown in Table 1.
In addition, an image evaluation experiment was performed in the same manner as in Example 1. As a result, the dot reproducibility of the image was ranked 4 in a 5-level evaluation.
[0107]
(Example 3)
Kneading, pulverization, and classification were performed using the same raw materials and production methods as in Example 1, and the particles were classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 1.2 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0108]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, an image evaluation experiment was performed in the same manner as in Example 1. As a result, the dot reproducibility of the image was ranked 4 in a 5-level evaluation.
[0109]
Example 4
Kneading, pulverization, and classification were performed using the same raw materials and production methods as in Example 1, and the particles were classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 0.8 parts
Mixing speed 850rpm
Mixing time 120sec
Mixer super mixer
[0110]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, an image evaluation experiment was performed in the same manner as in Example 1. As a result, the dot reproducibility of the image was ranked 4 in a 5-level evaluation.
[0111]
(Example 5)
Kneading, pulverization, and classification were performed using the same raw materials and production methods as in Example 1, and the particles were classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 850rpm
Mixing time 120sec
Mixer super mixer
[0112]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, an image evaluation experiment was performed in the same manner as in Example 1. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0113]
(Example 6)
Kneading, pulverization, and classification were performed using the same raw materials and production methods as in Example 1, and the particles were classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 1.2 parts
Mixing speed 850rpm
Mixing time 120sec
Mixer super mixer
[0114]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, an image evaluation experiment was performed in the same manner as in Example 1. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0115]
(Example 7)
Toner binder synthesis:
724 parts of bisphenol A ethylene oxide 2-mole adduct, 276 parts of isophthalic acid and 2 parts of dibutyltin oxide were placed in a reaction vessel equipped with a cooling tube, a stirrer and a nitrogen introduction tube, and reacted at 230 ° C. for 8 hours under normal pressure. The reaction was further carried out at a reduced pressure of 10 to 15 mmHg for 5 hours, followed by cooling to 160 ° C., and 32 parts of phthalic anhydride was added thereto and reacted for 2 hours. Subsequently, it cooled to 80 degreeC and reacted with 188 parts of isophorone diisocyanate in ethyl acetate for 2 hours, and the isocyanate containing prepolymer I was obtained. Next, 267 parts of prepolymer I and 14 parts of isophoronediamine were reacted at 50 ° C. for 2 hours to obtain urea-modified polyester I having a weight average molecular weight of 64,000.
In the same manner as above, 724 parts of bisphenol A ethylene oxide 2 mol adduct and 276 parts of terephthalic acid were subjected to polycondensation at 230 ° C. for 8 hours under normal pressure, and then reacted for 5 hours at a reduced pressure of 10 to 15 mmHg to obtain a peak molecular weight of 5000. An unmodified polyester A was obtained.
200 parts of urea-modified polyester I and 800 parts of unmodified polyester A were dissolved and mixed in 2000 parts of an ethyl acetate / MEK (1/1) mixed solvent to obtain an ethyl acetate / MEK solution of toner binder I. Part of the mixture was dried under reduced pressure to isolate toner binder I. As a result of analysis, Tg was 62 ° C.
[0116]
Toner production:
240 parts of toner binder I in ethyl acetate / MEK solution
Pentaerythritol tetrabehenate (melt viscosity 25 cps) 20 parts
Copper phthalocyanine blue pigment
(CI Pigment Blue 15: 3) 4 parts
The above raw materials were stirred in a beaker at 12000 rpm with a TK homomixer at 60 ° C., and uniformly dissolved and dispersed to prepare a toner material solution.
706 parts of ion exchange water
Hydroxyapatite 10% suspension
(Nippon Chemical Industry Co., Ltd. Superiteite 10) 294 parts
Sodium dodecylbenzenesulfonate 0.2 parts
The raw materials were placed in a beaker and dissolved uniformly. Thereafter, the temperature was raised to 60 ° C., and the toner material solution was added and stirred for 10 minutes while stirring at 12000 rpm with a TK homomixer. The mixture was then transferred to a stir bar and a flask equipped with a thermometer, heated to 30 ° C., the solvent was removed under reduced pressure, filtered, washed, dried, and then subjected to air classification to obtain toner particles. The volume average particle diameter was 6.3 μm. To 100 parts of the toner particles, an additive was mixed under the following mixing conditions to obtain a toner.
Silica fine powder 0.8 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0117]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
The toner obtained by the above production method and the carrier were mixed at a ratio of 2.5 parts with respect to 97.5 parts of the carrier to produce a two-component developer.
The obtained developer was set in a copying machine in which the latent image carrier is an OPC drum photoreceptor and the cleaning method is blade cleaning, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0118]
(Example 8)
Powders were produced and classified by the same raw materials and production method as in Example 7, and classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base coloring particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0119]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
Further, a two-component developer was produced in the same manner as in Example 7, and an image evaluation experiment was conducted. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0120]
Example 9
Powders were produced and classified by the same raw materials and production method as in Example 7, and classified into a particle size distribution with an average particle size of 6.5 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 0 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0121]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
Further, a two-component developer was produced in the same manner as in Example 7, and an image evaluation experiment was conducted. As a result, the dot reproducibility of the image was ranked 1 in a 5-grade evaluation.
[0122]
(Example 10)
Resin Polyester resin 100 parts
10 parts of carbon black pigment
Charge control agent Zinc salicylate 2 parts
Release agent Rice wax 5 parts
Additives Styrene acrylic resin 3 parts
The raw materials were sufficiently mixed with a mixer, and then melt kneaded with a twin screw extruder at a barrel temperature of 100 ° C. and a rotation speed of 120 rpm. The kneaded product was rolled and cooled, coarsely pulverized by a cutter mill, pulverized by a fine pulverizer using a jet stream, and then classified into a particle size distribution having an average particle size of 6 μm using a swirling air classifier. Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 0.2 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0123]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
The toner obtained by the above production method and the carrier were mixed at a ratio of 2.5 parts with respect to 97.5 parts of the carrier to produce a two-component developer.
The obtained developer was set in a copying machine in which the latent image carrier is an OPC drum photoreceptor and the cleaning method is blade cleaning, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 3 on a five-point scale.
[0124]
(Example 11)
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 10, and classified into a particle size distribution with an average particle size of 6 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 0.3 parts
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0125]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, a two-component developer was produced in the same manner as in Example 10, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 3 on a five-point scale.
[0126]
(Example 12)
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 10, and classified into a particle size distribution with an average particle size of 6 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 700rpm
Mixing time 120sec
Mixer super mixer
[0127]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, a two-component developer was produced in the same manner as in Example 10, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 4 in a 5-level evaluation.
[0128]
(Example 13)
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 10, and classified into a particle size distribution with an average particle size of 6.1 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 850rpm
Mixing time 120sec
Mixer super mixer
[0129]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, a two-component developer was produced in the same manner as in Example 10, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0130]
(Example 14)
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 10, and classified into a particle size distribution with an average particle size of 6 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 1 part
Mixing speed 1000rpm
Mixing time 120sec
Mixer super mixer
[0131]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, a two-component developer was produced in the same manner as in Example 10, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0132]
(Example 15)
Kneading, pulverization, and classification were carried out using the same raw materials and production method as in Example 10, and classified into a particle size distribution with an average particle size of 6 μm.
Further, an additive (silica fine powder) was mixed with 100 parts of the base colored particles under the following mixing conditions to produce a toner.
Silica fine powder 1.2 parts
Mixing speed 850rpm
Mixing time 120sec
Mixer super mixer
[0133]
After the toner was manufactured, the compaction state and fluidity were measured by the evaluation apparatus of the present invention, and the results are shown in Table 1.
In addition, a two-component developer was produced in the same manner as in Example 10, and an image evaluation experiment was performed. As a result, the dot reproducibility of the image was ranked 5 in a 5-grade evaluation.
[0134]
The measurement results of Examples 1 to 15 are summarized in Table 1.
[0135]
[Table 1]

[0136]
As can be seen from the above results, there is a strong correlation between the fluidity evaluation value of the toner powder phase by the evaluation apparatus of the present invention and the dot reproducibility, and the dot reproducibility is evaluated by the evaluation apparatus of the present invention. I understand that I can do it. Further, in order to obtain a toner having good fluidity necessary for obtaining a high image quality with good dot reproducibility, it is necessary to satisfy the following conditions.
(1) The value of the torque when the conical rotor enters is 0.1 to 8.3 mNm.
(2) The value of the load when the conical rotor enters is 0.01 to 1.14N.
[0137]
If the torque value when the conical rotor enters is less than 0.1 mNm, the charging characteristics other than the fluidity of the toner are deteriorated and the image quality is deteriorated. When the load value at the time of entering the conical rotor is less than 0.01 N, the charging characteristics of the toner are deteriorated and the image quality is deteriorated. When the load value is larger than 1.14 N, the fluidity of the toner is lowered and the dot reproducibility is deteriorated.
[0138]
【The invention's effect】
(1) According to the powder fluidity evaluation apparatus of claims 1 to 9, after measuring the height of the powder phase and evaluating the compacted state, the powder phase is allowed to enter while rotating the conical rotor, By measuring the torque or load generated when the conical rotor moves in the powder phase, the fluidity of the powder can be evaluated with high accuracy and without individual differences.
[0139]
(2) Claim 9 According to the method for producing a toner for developing an electrostatic charge image described in (1), since a toner having high image quality is defined by the powder fluidity evaluation apparatus, high image quality can be obtained.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an example of a powder fluidity evaluation apparatus of the present invention.
2A is a cross-sectional view of a conical rotor, and FIG. 2B is a plan view thereof.
FIGS. 3A and 3B are plan views showing the shape of another conical rotor, and FIG. 3C is a cross-sectional view.
FIG. 4 is a graph showing the relationship between torque and dot reproducibility when a conical rotor is inserted in Examples 1 to 15.
FIG. 5 is a graph showing the relationship between the load at the time of entering the conical rotor and dot reproducibility in Examples 1 to 15.
FIG. 6 is a schematic view showing an example of a toner manufacturing apparatus using the evaluation apparatus of the present invention in the toner manufacturing process.
FIG. 7 is a schematic view showing an example of a developing device using toner manufactured using the evaluation device of the present invention.

Claims (9)

In the apparatus for evaluating the fluidity of the powder by allowing the conical rotor to enter the powder phase while rotating, and measuring the torque or load generated when the conical rotor moves in the powder phase,
Means for measuring the amount of change from the reference height of the powder phase , and a vibrator provided under the container for storing the powder ,
The powder phase state stabilized by the pressurized vibrator, the subsequent powder phase measuring an amount of change from the reference height, and weight information of the change amount and the powder from the reference height of the powder phase An apparatus for evaluating the fluidity of a powder, characterized by measuring a torque or a load generated when the conical rotor moves in a powder phase after evaluating the compacted state.   2. The powder fluidity evaluation apparatus according to claim 1, wherein the height of the powder phase is measured in advance, and then the conical rotor is caused to enter the powder phase while rotating, and the conical rotor moves in the powder phase. An apparatus for evaluating the fluidity of a powder, characterized by measuring a torque or a load generated when the powder is produced.   3. The powder fluidity evaluation apparatus according to claim 1, wherein the powder phase has a height of 5 to 50 mm.   The powder fluidity evaluation apparatus according to any one of claims 1 to 3, wherein the cone rotor has an apex angle of 20 to 150 °.   5. The powder fluidity evaluation apparatus according to any one of claims 1 to 4, wherein a groove is cut on a surface of the conical rotor.   The powder fluidity evaluation apparatus according to any one of claims 1 to 5, wherein the rotational speed of the conical rotor is 0.1 to 100 rpm.   The powder fluidity evaluation apparatus according to any one of claims 1 to 6, wherein the penetration speed of the conical rotor is 0.5 to 150 mm / min. The powder fluidity evaluation apparatus according to any one of claims 1 to 7 , wherein the powder phase has a porosity of 0.4 to 0.7. Sex evaluation device. An electrostatic charge image development characterized in that the powder fluidity evaluation apparatus according to any one of claims 1 to 8 is used to perform an evaluation during a toner manufacturing process, and a toner is manufactured based on the evaluation. Of manufacturing toner.

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