JP3591464B2 - Apparatus and method for producing kneaded material for producing toner - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a manufacturing apparatus and a manufacturing method of a kneaded material for manufacturing a toner used in, for example, an electrophotographic method, an electrostatic printing method, and the like.
[0002]
[Prior art]
In general, in electrophotography, an electric latent image is formed on a photoreceptor by various methods using a photoconductive substance, and then the latent image is developed using toner. Further, a method of transferring a toner image to a transfer material such as paper, and then fixing the toner image by various methods to obtain an object is adopted.
[0003]
The toner (dry toner) is prepared by using a binder resin and a pigment as main raw materials, and further adding additives such as a charge control agent and a wax. Describing the toner production method, the toner production process includes a kneading step of a binder resin, a pigment and an additive, a pulverizing step of a kneaded material prepared in the kneading step, a classification step, and an external addition step.
[0004]
Further, an apparatus for producing a kneaded material for toner production supplies an open-roll kneader for melt-kneading the binder resin, the pigment and the additive, and supplies the binder resin, the pigment and the additive to the open-roll kneader. And a feeder. The open roll kneader has a pair of open rolls. Each of the open rolls has a cylindrical shape, and both ends are rotatably supported by bearings in a state in which both open rolls extend parallel to each other so that gaps extending at regular intervals in the axial direction are provided between the open rolls. .
[0005]
Each of the open rolls is formed so as to have a hollow interior and capable of supplying a heat medium (refrigerant) such as water or oil, and is configured such that the outer surface temperature of each open roll can be arbitrarily adjusted. The feeder is provided above one end of the open roll, and the feeder is configured to be able to supply a raw material to one end of the open roll.
[0006]
Now, in order to manufacture a toner using the kneaded material manufacturing apparatus, first, a binder resin, a pigment, and an additive are respectively measured in a predetermined amount, and then supplied into a feeder, and the raw material is supplied from a supply port of the feeder. Supply between one end of open roll. Then, the raw material stays between the one supply sides of the two open rolls to form a bank, and at the bank, the raw material is swallowed into the bank by the rotation of the open roll, and convection is formed.
[0007]
Further, in the bank, the binder resin swallowed by the convection melts due to the heat generated by the heating and kneading of the open roll, and becomes a fluid. The molten binder resin wraps around the surface of the open roll, pigments and additives adhere to the binder resin, and are further kneaded into the binder resin while being transferred to the other end of the open roll. A kneaded product is prepared. The kneaded material is discharged from the other end discharge side of the open roll, and after the kneaded material is cooled and solidified, a pulverizing step, a classifying step, an external adding step, and the like of the kneaded substance are performed to produce a toner.
[0008]
In the production process of the kneaded material, the open roll kneader has an open roll outer surface that is exposed and has high heat dissipation, so that it is excellent in the cooling performance of the raw material during melt kneading, and the melt kneading of the raw material can be performed at low temperature. It is possible. When the raw materials are melt-kneaded at a low temperature, the binder resin does not melt, and a high compression force and shear force are applied to the pigments and additives while maintaining a high viscosity to make the pigments and additives finer. To be dispersed in the binder resin. Therefore, it is preferable that the temperature of the binder resin at the time of melt-kneading is set to around Tm (melting temperature) of the binder resin as disclosed in JP-A-2000-75548.
[0009]
[Problems to be solved by the invention]
In the above-mentioned conventional kneaded material manufacturing apparatus, at the time of supplying the raw material, the pigment and the additive can be made finer by the compressive force and the shear force generated by the melt-kneading of the binder resin accompanying the rotation of the open roll. However, pigments and additives are miniaturized as they are transferred to the discharge side, and the finer they are, the greater the compressive force and shearing force required to further refine pigments, additives, etc. It becomes.
[0010]
At this time, the gap between the open rolls extends with a certain interval in the axial direction of the open rolls. Therefore, even if the pigment, the additive, and the like are transferred to the discharge side, the compressive force and the shearing force acting on the pigment and the additive do not change from when the raw material is supplied. Therefore, the pigment and the additive are kneaded into the binder resin in a state where the pigment and the additive are not miniaturized on the discharge side of the open roll, and the dispersibility of the pigment in the binder resin is reduced. As a result, when an electric latent image formed by an electrophotographic method is developed using the obtained toner, there is a problem that the image quality of a toner image transferred to a material to be transferred is deteriorated.
[0011]
The present invention has been made by paying attention to such problems existing in the related art. An object of the present invention is to provide a kneaded material manufacturing apparatus and a kneaded material manufacturing method for manufacturing a toner in which at least a pigment is uniformly dispersed in a binder resin in a finely divided state, and a deterioration in image quality of a toner image can be prevented. It is to provide a method.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, the apparatus for producing a kneaded material for producing a toner according to the present invention according to claim 1 includes a plurality of open rolls, and one end between the opposing open rolls among the open rolls. A toner production device having a melt-kneading device that melt-kneads a raw material composed of at least a binder resin and a pigment supplied to a supply side by rotation of the open roll and prepares a kneaded product composed of the raw material from the other discharge side. A gap between the opposing open rolls is gradually narrowed from the supply side of the raw material to the discharge side, and the gap is gradually reduced from the supply side to the discharge side. At least the compressive force and the shear force acting on the pigment are increased.
[0013]
According to a second aspect of the present invention, in the apparatus for manufacturing a kneaded product for manufacturing a toner according to the first aspect, the gap at the supply side edge of the opposed open roll is set to the gap at the discharge side edge. It is characterized by being set to 1.5 to 4.5 times.
[0014]
According to a third aspect of the present invention, in the apparatus for manufacturing a kneaded product for manufacturing a toner according to the first or second aspect, the outer surfaces of the opposed open rolls are provided so as to be capable of controlling the temperature, and the open rolls are opened. The temperature of the binder resin during melt-kneading between the rolls is set to be equal to or lower than the melting temperature (Tm) of the binder resin.
[0015]
According to a fourth aspect of the present invention, there is provided a method for producing a kneaded product for producing a toner according to any one of the first to third aspects. A raw material comprising at least a binder resin and a pigment is supplied to one end supply side between the rolls, and the compression force and the shear force are increased as the raw material is transferred from the supply side to the discharge side while being melted and kneaded by rotation of the open roll. The method is characterized in that at least the pigment is made to act on the pigment so as to gradually increase in size, and the pigment is dispersed in the binder resin in a state of being finer than at the time of supply at the time of discharging the kneaded material composed of the raw material.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
1 and 2 are schematic diagrams showing a kneaded material manufacturing apparatus 10 for manufacturing a toner (hereinafter, simply referred to as a manufacturing apparatus 10). As shown in FIGS. 1 and 2, the manufacturing apparatus 10 includes an open roll kneader 11 as a melt kneading apparatus having a pair of open rolls 11a and 11b opposed to each other, and a screw feeder as a fixed amount feeder in the raw material supply mechanism. 12 is provided. The open roll kneader 11 includes a binder resin, a pigment, and an additive supplied between one end supply sides of the pair of open rolls 11a and 11b (the additive in the present embodiment includes a charge control agent and a wax. ) Is melt-kneaded by the rotation of the open rolls 11a and 11b, and the kneaded material is discharged from the other end discharge side. Further, the gap between the pair of open rolls 11a and 11b is gradually narrowed from the one end supply side of the raw material toward the other end discharge side.
[0017]
First, the screw feeder 12 will be described. The screw feeder 12 is mounted on a mounting table 13 installed on the outside of one end supply side (the upper side in FIG. 1) of the pair of open rolls 11a and 11b, and the binding is performed. A hopper 14 capable of storing a resin, a pigment, and additives is provided at an upper portion. A lower part of the hopper 14 is provided with a transfer path 15 which communicates with the inside of the hopper 14 and extends cylindrically from the hopper 14 to the open roll kneader 11 side. The open rolls 11a and 11b are disposed above one end supply side.
[0018]
A screw (not shown) spirally extending from the hopper 14 to the tip of the transport path 15 is rotatably provided in the transport path 15. Then, by rotating the screw in a predetermined direction, the binder resin, the pigment, and the additive are conveyed from the hopper 14 side to the front end side of the conveying path 15 and supplied between the pair of open rolls 11a and 11b. I have.
[0019]
Next, the open roll kneader 11 will be described. Each of the pair of open rolls 11a and 11b has a cylindrical shape having a spiral groove (not shown) on its surface. A shaft 11d is formed on each of the open rolls 11a and 11b along a center line extending in the length direction, and both ends are supported by bearings 11c such that the pair of shafts 11d are substantially V-shaped in plan. . As shown by arrows in FIG. 2, the open rolls 11a and 11b are configured to be rotatable inward by a motor (not shown).
[0020]
The inside of each of the open rolls 11a and 11b is formed in a hollow shape, and a heat medium (refrigerant) such as water or oil is supplied into each of the open rolls 11a and 11b. It is configured to be controllable.
[0021]
It is preferable that the temperature of the binder resin between the pair of open rolls 11a and 11b during the melt-kneading of the raw material is set to be equal to or lower than the melting temperature (Tm) of the binder resin. When the temperature of the binder resin exceeds the melting temperature, the melting of the binder resin is promoted to become a low-viscosity fluid, and the cutting of the molecules of the binder resin is promoted, and the compressive force and the shear force acting on the pigment and the additive are increased. It is not preferable because it becomes smaller.
[0022]
In addition, the melting temperature of the binder resin in the present embodiment is measured by using a high-low type flow tester (CFT-500 manufactured by Shimadzu Corporation), the diameter of the pores of the die is 1 mm, the length is 1 mm, the load is 20 kgf, and 1cm under the condition of temperature rate 5 ° C / min ³ Is set to a temperature corresponding to 1/2 of the height from the outflow start point to the outflow end point when the sample is melted out.
[0023]
Both ends of the shaft 11d are supported by the bearing 11c in a state in which the gap between the open rolls 11a and 11b gradually narrows from one end to the other end of the open rolls 11a and 11b. The gap D1 at the edge on the one end supply side of both open rolls 11a and 11b is formed wider than the gap D2 on the edge on the other end discharge side.
[0024]
During the melt-kneading of the raw materials, the compressive force and the shearing force acting on the pigment and the additive due to the kneading of the molten binder resin are gradually increased from the supply side to the discharge side of the open rolls 11a and 11b. Therefore, it is preferable that the gap D1 is set to be 1.5 to 4.5 times the gap D2.
[0025]
When the gap D1 is formed to be smaller than 1.5 times the gap D2, the amount by which the gap becomes narrower from the supply side to the discharge side is small, and the difference between the compressive force and the shear force between the supply side and the discharge side is reduced. Can hardly be formed. Therefore, it is not preferable because the pigments and additives that have been refined on the supply side are difficult to further refine. On the other hand, if the gap D1 is formed to be larger than 4.5 times the gap D2, the raw material supplied between the open rolls 11a and 11b falls from between the open rolls 11a and 11b. That is, the raw material does not accumulate between the one end supply sides of the open rolls 11a and 11b, and a bank cannot be formed. In the embodiment, D1 is set in the range of 0.15 to 2 mm.
[0026]
When the diameter of each of the open rolls 11a and 11b is L (mm), the supply amount of the raw material supplied between the pair of open rolls 11a and 11b is in the following range.
1 x (L / 100) ^2.2 ~ 5 × (L / 100) ^2.7 (Kg / h)
Is preferably set to. If the supply amount is less than the above range, the supply amount of the raw material decreases, and the productivity of the kneaded material is undesirably reduced. On the other hand, when the supply amount exceeds the above range, the melting of the raw material is likely to be incomplete, and undesirably the lump is formed on the bank.
[0027]
Then, a raw material made of the binder resin, pigment and other additives moved in the transport path 15 is supplied to one end supply side between the open rolls 11a and 11b, and the raw material is melt-kneaded between the pair of open rolls 11a and 11b. Is done. Further, the melted binder resin is wound around the surface of the one open roll 11a having the higher outer surface temperature, and the kneaded material is prepared by mixing the pigment and additives into the wound binder resin. Has become. At this time, the outer surface temperature of the one open roll 11a is adjusted such that the temperature of the binder resin wound around the outer surface is equal to or lower than the melting temperature of the binder resin. As shown by the broken line in FIG. 2, a collecting section 16 for collecting the kneaded material is provided below the other ends of the open rolls 11a and 11b.
[0028]
Next, the raw material of the kneaded material for producing the toner will be described. First, the kind of the binder resin is not particularly limited, and a known binder resin for a black toner or a color toner may be used. Examples include polyester resins, polystyrene resins, styrene resins such as styrene-acrylate copolymer resins, acrylic resins such as polymethyl methacrylate, polyolefin resins such as polyethylene, polyurethane resins, and epoxy resins. These binder resins are used alone or in combination of two or more. The binder resin is usually blended in the toner in an amount of 80 to 95% by weight.
[0029]
The pigment is not particularly limited, and red pigments such as quinacridone, brilliant carmine 6B, and permanent red; yellow pigments such as benzimidazolone and dichlorobenzidine; blue pigments such as cobalt blue and copper phthalocyanine; chrome green; and chromium oxide. And green pigments such as CI Pigment Green B, and black pigments such as carbon black and acetylene black. These pigments are used alone or in combination of two or more. The pigment is usually blended in the toner in an amount of 3 to 10% by weight.
[0030]
The charge control agent as the additive is not particularly limited, and a known charge control agent for negatively charged or positively charged toner for black toner or color toner can be used. Examples of the charge control agent for negatively charged toner include surfactants such as chromium, zinc, zirconium complex or salt compounds of salicylic acid or a derivative thereof, azo complex dyes, and long-chain alkyl carboxylate. Examples of the charge control agent for the positively charged toner include a nigrosine dye or a derivative thereof, a quaternary ammonium salt, and a guanidine salt. Examples of the wax include natural waxes such as carnauba wax and synthetic waxes, silicone polymers, higher fatty acids, polyolefin polymers, and low molecular weight polymers.
[0031]
Next, a method for producing a kneaded material using the production apparatus 10 will be described.
[0032]
Now, a predetermined amount of the binder resin, the pigment, and the additive are measured, and the raw materials are supplied into the hopper 14. Thereafter, the manufacturing apparatus 10 is operated to rotate the screw in the transport path 15 in a predetermined direction, and the raw material is transported from the hopper 14 side of the screw feeder 12 to the open roll kneader 11 along the transport path 15. Since the screw rotates and constantly stirs the binder resin, the pigment, and the additive in the transport path 15, the stagnation of the raw material in the transport path 15 is prevented.
[0033]
Next, the outer surface temperature of each open roll 11a, 1b is adjusted, the outer surface temperature of one open roll 11a is set to a higher temperature than the other open roll 11b, and a temperature difference is generated between the two open rolls 11a, 11b. At the same time, one of the open rolls 11a is rotated such that its rotation speed is higher than the rotation speed of the other open roll 11b.
[0034]
Then, the raw material transported in the transport path 15 falls and is supplied between one end supply sides of the pair of open rolls 11a and 11b, and is deposited between the open rolls 11a and 11b to form a bank. The rotation of the opposing open rolls 11a and 11b toward the inside causes the raw material to be swallowed into the bank and convection occurs. Then, the binder resin in the bank is heated and melted by the heat transfer effect on the surface of the one open roll 11a on the high temperature side, and is wound around the surface of the one open roll 11a.
[0035]
At this time, since the outer surface temperature of one of the open rolls 11a is set so that the temperature of the binder resin during the melt-kneading is equal to or lower than the melting temperature (Tm) of the binder resin, the melting of the binder resin is promoted. Of the binder resin is prevented from being promoted. The binder resin of the high-viscosity fluid is kneaded in the gap between the open rolls 11a and 11b to generate a compressive force and a shearing force. Dispersed in binder resin.
[0036]
Further, the shear force is calculated by integrating the shear rate and the binder resin viscosity, and the binder resin viscosity often decreases to about one-tenth when, for example, the binder resin temperature increases by 10 ° C. . Therefore, when the shear rate is the same, when the binder resin temperature rises and the binder resin viscosity decreases, the shear force also decreases. That is, since the outer surface temperature of the one open roll 11a is set to be equal to or lower than the melting temperature of the binder resin, an increase in the binder resin temperature is suppressed, and a decrease in the shearing force is suppressed.
[0037]
Subsequently, the molten binder resin adheres to the surface of one of the open rolls 11a, and while the pigment and the additive are kneaded on the surface of the binder resin, the binder resin is repeatedly kneaded under a compressive force and a shear force. Is transported to the other end discharge side due to the difference between the rotation speeds of the pair of open rolls 11a and 11b. At this time, since the gap between the pair of open rolls 11a and 11b becomes narrower from the supply side to the discharge side, the compressive force and the shearing force on the pigment, the additive, and the like decrease toward the discharge side. growing.
[0038]
Therefore, as the raw material is transferred to the discharge side, pigments, additives, and the like are miniaturized. Further, as the pigments and additives are miniaturized, a larger compressive force and shearing force are required to miniaturize the pigments and additives. At this time, the gap becomes narrower as the pigment, the additive and the like are transferred to the discharge side, so that the compressive force and the shear force acting on the pigment, the additive and the like gradually increase, and the miniaturization is promoted. Then, the finely divided pigment, additives, and the like are strongly kneaded into the binder resin, and the uniformly dispersed kneaded material is collected by the collection unit 16 from the other end discharge side.
[0039]
After cooling and solidifying the obtained kneaded material, the kneaded material is roughly pulverized, finely pulverized and classified, and then subjected to a surface treatment to produce a toner. In the obtained toner, the change in the molecular weight distribution of the binder resin is small, and the pigments and additives having a fine particle diameter are uniformly dispersed in the binder resin.
[0040]
The effects exerted by the above embodiment will be described below.
[0041]
The manufacturing apparatus 10 was configured by forming the open roll kneader 11 so that the gap between the pair of open rolls 11a and 11b gradually narrowed from the one end supply side to the other end discharge side. Therefore, unlike the related art in which the gap between the open rolls 11a and 11b is formed the same from the supply side to the discharge side, the compression acting on the pigment and the additive as the pigment and the additive are transferred to the discharge side. Force and shear force can be gradually increased. Therefore, the pigment and the additive can be made finer gradually as they are transferred from the supply side to the discharge side, and can be uniformly dispersed in the binder resin. As a result, when an electric latent image formed by electrophotography is developed using a toner prepared from the obtained kneaded material, unevenness, dullness, and transparency of the image quality of the toner image transferred to the material to be transferred are increased. Can be prevented, and a decrease in image quality can be prevented.
[0042]
The gap D1 is set to be 1.5 to 4.5 times the gap D2. Therefore, the gap between the supply side and the discharge side is almost eliminated due to the gap D1 being too narrow, and the compression force and the shear force generated from the supply side toward the discharge side can be gradually increased. . Also, the amount of the raw material supplied between the open rolls 11a and 11b falls from between the open rolls 11a and 11b can be reduced, so that the bank can be reliably formed and the waste of the raw material can be eliminated.
[0043]
Since the outer surface temperature of one of the open rolls 11a is set so that the temperature of the binder resin during the melt-kneading is equal to or lower than the melting temperature of the binder resin, it is possible to suppress the promotion of the cutting of the molecules of the binder resin. be able to. Therefore, it is possible to keep the fixability of the obtained toner to the transfer material constant by reducing the change in the molecular weight distribution of the binder resin before and after the kneading and kneading of the raw materials.
[0044]
In the transport path 15 of the screw feeder 12, since the screw rotates and constantly stirs the binder resin, the pigment and the additive, it is possible to prevent the raw material from staying in the transport path 15. Therefore, it is possible to improve the quantitativeness of the toner by eliminating the problem that the mass of the raw material is supplied from the transport path 15 between the open rolls 11a and 11b.
[0045]
・ The range of raw material supply is 1 × (L / 100) ^2.2 ~ 5 × (L / 100) ^2.7 (Kg / h), it is possible to prevent a decrease in the productivity of the kneaded material. Further, it is possible to prevent the raw material from being incompletely melted at the time of melt-kneading, and to prevent the occurrence of lump on the bank.
[0046]
This embodiment can be embodied with the following modifications.
[0047]
A kneaded material manufacturing apparatus 10 for manufacturing a toner shown in FIG. 3 may be used. The open roll kneader 11 has one open roll 11a (left side in FIG. 3) formed in a cylindrical shape, and both ends of the open roll 11a are bearings 11c in a state where the shaft 11d is orthogonal to both bearings 11c. It is supported by. On the other hand, the other (rightward in FIG. 3) open roll 11b is formed in a cylindrical shape whose diameter increases from one end to the other end, and the shaft 11d of the other open roll 11b is orthogonal to both bearings 11c. In this state, both ends are supported by the bearing 11c. The gap between the open rolls 11a and 11b is gradually narrowed from one end to the other end.
[0048]
Alternatively, in the manufacturing apparatus 10 shown in FIG. 3, the other open roll 11 b is formed in a cylindrical shape, and the one open roll 11 a is formed in a cylindrical shape whose diameter increases from one end to the other end. Good. The gap between the open rolls 11a and 11b may be gradually narrowed from one end to the other end.
[0049]
A kneaded material manufacturing apparatus 10 for manufacturing a toner shown in FIG. 4 may be used. The open roll kneader 11 is formed in a cylindrical shape in which both open rolls 11a and 11b increase in diameter from one end to the other end, and both ends of the shaft 11d are orthogonal to the both bearings 11c. It is supported by. The gap between the open rolls 11a and 11b is narrower from one end to the other end.
[0050]
In the embodiment, the kneaded material manufacturing apparatus 10 for toner production is provided by using the open roll kneading machine 11 having the pair of open rolls 11a and 11b. However, the open roll kneading using three or more open rolls. The machine 11 may be used.
[0051]
In the embodiment, the screw feeder 12 is used as the quantitative feeder of the raw material supply mechanism. However, the raw material may be supplied to the open roll kneader 11 using a table feeder, a mono pump or the like as the quantitative feeder. The raw material may be supplied to the open roll kneading machine 11 manually without using the raw material.
[0052]
In the embodiment, the kneaded material is manufactured using the binder resin, the pigment, the wax, and the charge control agent as the raw materials. However, the kneaded material may be manufactured using only the binder resin and the pigment. A kneaded product may be produced by using a pigment, a wax, and one of a wax and a charge control agent.
[0053]
In the embodiment, the outer surface temperature of one open roll 11a is set higher than the outer surface temperature of the other open roll 11b, and a temperature difference is generated between the two open rolls 11a, 11b. May be set to be equal to or slightly different from each other so that the temperature of the open rolls 11a and 11b is equal to or lower than the melting temperature. At this time, the rotation speed is set to be different between the open rolls 11a and 11b so that the kneaded material moves to the other end discharge side.
[0054]
In the embodiment, spiral grooves are formed on the surfaces of both open rolls 11a and 11b, but may be omitted.
[0055]
Further, technical ideas that can be grasped from the embodiment will be described below.
[0056]
The kneaded material for toner production according to any one of claims 1 to 3, wherein a gap between the open rolls at the supply-side edge of the raw material is set to 0.15 to 2 mm. Manufacturing equipment.
[0057]
4. The kneading apparatus according to claim 1, further comprising a raw material supply mechanism configured to supply the raw material to one end supply side between the open rolls, wherein the raw material supply mechanism is a fixed-quantity feeder. 5. Product manufacturing equipment. With such a configuration, the raw materials can be supplied to the melt-kneading apparatus quantitatively and uniformly.
[0058]
When the diameter of the open roll is set to L (mm), the supply amount of the raw material is 1 × (L / 100) ^2.2 ~ 5 × (L / 100) ^2.7 The apparatus for producing a kneaded product for producing a toner according to any one of claims 1 to 3, wherein the apparatus is set to a range shown in (kg / h). With such a configuration, it is possible to prevent the supply amount of the raw material from being reduced and the productivity of the kneaded material from being reduced. In addition, it is possible to prevent the supply amount from becoming excessive and the raw material from being incompletely melted.
[0059]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
[0060]
According to the apparatus for manufacturing a kneaded product for manufacturing a toner according to the first aspect of the present invention, at least the pigment is uniformly dispersed in the binder resin in a finely divided state, thereby preventing the deterioration of the image quality of the toner image. be able to.
[0061]
According to the kneaded material manufacturing apparatus for manufacturing a toner according to the second aspect of the invention, in addition to the effects of the first aspect, a compressive force generated from the supply side toward the discharge side is obtained. The shear force can be increased. In addition, the amount of the raw material supplied between the open rolls falls from between the open rolls is reduced, so that the bank can be reliably formed, and the waste of the raw materials can be eliminated.
[0062]
According to the apparatus for producing a kneaded product for producing a toner according to the third aspect of the present invention, in addition to the effects of the first or second aspect of the invention, cutting of molecules of the binder resin between the open rolls. Can be suppressed from being promoted. Therefore, it is possible to keep the fixability of the obtained toner to the transfer material constant by reducing the change in the molecular weight distribution of the binder resin before and after the kneading and kneading of the raw materials.
[0063]
According to the method for producing a kneaded material for producing a toner according to the fourth aspect of the present invention, at least the pigment is uniformly dispersed in the binder resin in a finely divided state, thereby preventing the image quality of the toner image from deteriorating. be able to.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing a kneaded material manufacturing apparatus according to an embodiment.
FIG. 2 is a schematic side view showing a kneaded material manufacturing apparatus according to the embodiment.
FIG. 3 is a schematic plan view showing another example of a kneaded material manufacturing apparatus.
FIG. 4 is a schematic plan view showing another example of a kneaded material manufacturing apparatus.
[Explanation of symbols]
D1 Gap at the supply side edge of the open roll
D2 Gap at the discharge side edge of the open roll
10. Kneaded material manufacturing device for toner production
11 Open roll kneader as melt kneading device
11a, 11b open roll

Claims (4)

It comprises a plurality of open rolls, melts and kneads a raw material comprising at least a binder resin and a pigment supplied to one end supply side between opposing open rolls of the open rolls by rotation of the open roll, and the other end. An apparatus for producing a kneaded material for toner production, comprising a melt-kneading device for preparing a kneaded material comprising the raw material from a discharge side, wherein a gap between the opposed open rolls is changed from a raw material supply side to a raw material discharge side. An apparatus for producing a kneaded material for producing a toner, characterized in that the compression force and the shearing force acting on at least the pigment are increased from the supply side to the discharge side, and the compression force and the shear force are increased from the supply side to the discharge side. 2. The kneaded material for toner production according to claim 1, wherein a gap at a supply side edge of the opposing open rolls is set to be 1.5 to 4.5 times a gap at a discharge side edge. Manufacturing equipment. The outer surface of the opposing open rolls is provided so as to be temperature-controllable, and the temperature of the binder resin being melt-kneaded between the open rolls is set to be equal to or lower than the melting temperature (Tm) of the binder resin. An apparatus for producing a kneaded product for producing a toner according to claim 1 or 2. A raw material comprising at least a binder resin and a pigment is supplied to one end supply side between opposed open rolls of the kneaded material production apparatus for producing a toner according to any one of claims 1 to 3, By rotating the open roll, the raw material is melted and kneaded, and the compressive force and the shearing force are applied to at least the pigment so as to gradually increase as the raw material is transferred from the supply side to the discharge side. A method for producing a kneaded material for producing a toner, comprising: dispersing at least a pigment in a binder resin in a state of being finer than at the time of supply.

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