Apparatus for adjusting the moisture content of a pigment suspension and method for adjusting the moisture content of a pigment suspension

Abstract

The present invention provides a moisture content adjustment device for pigment suspensions that can prepare a wet cake with suppressed uneven moisture content distribution while suppressing foaming of the pigment suspension during processing. [Solution] The pigment suspension moisture content adjustment device (I) 1A comprises a first tank 6 for containing a pigment suspension, a heating element 2 positioned above the first tank 6 to which the pigment suspension adheres and evaporates the water in the pigment suspension, and a first liquid conduit 5 for supplying the pigment suspension in the first tank 6 so as to adhere to the heating element 2. Furthermore, it includes a liquid receiver 37 positioned between the heating element 2 and the first tank 6 so that its lower end contacts the pigment suspension in the first tank 6, which guides the pigment suspension that did not adhere to the heating element 2 into the first tank 6, thereby circulating the pigment suspension between the first tank 6 and the heating element 2 to adjust the moisture content of the pigment suspension.

Description

Technical Field

[0001] The present invention relates to a device for adjusting the moisture content of a pigment suspension and a method for adjusting the moisture content of a pigment suspension.

Background Art

[0002] In recent years, pigments have been used as raw materials for manufacturing various products such as color filters and inkjet inks. For pigments, various reliabilities are required, not only color characteristics, but also the stability and filtration properties of colored compositions and inks prepared using the pigments, and the suitability when coating inks and the like on a substrate.

[0003] To enhance the color characteristics of a pigment, it is effective to reduce the primary particle size of the pigment. To reduce the primary particle size of the pigment, first, so-called salt milling is performed in which the pigment is mechanically kneaded using a kneader such as a kneader together with a water-soluble inorganic salt such as salt and a hydrophilic organic solvent. Next, after washing away the water-soluble inorganic salt and the hydrophilic organic solvent with water, a pigment suspension (hereinafter, also referred to as "wet cake") containing the refined pigment can be obtained by adjusting the moisture content by filter press, pressure filtration, hot air drying, or the like.

[0004] However, when producing a wet cake by adjusting the moisture content by a method such as a filter press, a difference in moisture content occurs between the surface and the inside of the obtained wet cake, and unevenness in the moisture content distribution easily occurs. In addition, a dryer has been proposed in which an object to be dried is uniformly brought into contact with a heating body to adjust the moisture content in the object to be dried (Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The inventors adjusted the moisture content of the pigment suspension using the dryer proposed in Patent Document 1. As a result, it was found that a wet cake with a uniform moisture distribution was obtained for the first few minutes after the start of processing. However, it was found that as the processing progressed, foaming tended to occur in the pigment suspension, and the moisture distribution of the resulting wet cake tended to become uneven.

[0007] Therefore, an object of the present invention is to provide a pigment suspension moisture content adjustment device that can prepare a wet cake with suppressed uneven moisture content distribution while suppressing foaming of the pigment suspension during processing. Another object of the present invention is to provide a method for adjusting the moisture content of a pigment suspension using this pigment suspension moisture content adjustment device. [Means for solving the problem]

[0008] In other words, the present invention provides a pigment suspension moisture content adjustment device comprising: a first tank for containing a pigment suspension containing water; a heating element disposed above the first tank for adhering to the pigment suspension and evaporating the water in the pigment suspension; and a first liquid conduit for supplying the pigment suspension in the first tank so as to adhere to the heating element; further comprising a liquid receiver disposed between the heating element and the first tank such that its lower end contacts the pigment suspension in the first tank, for guiding the pigment suspension that did not adhere to the heating element into the first tank, thereby circulating the pigment suspension between the first tank and the heating element to adjust the moisture content of the pigment suspension. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a moisture content adjustment device for a pigment suspension that can prepare a wet cake with suppressed uneven moisture content distribution while suppressing foaming of the pigment suspension during processing. Furthermore, according to the present invention, it is possible to provide a method for adjusting the moisture content of a pigment suspension using this moisture content adjustment device. [Brief explanation of the drawing]

[0010] [Figure 1A] This is a schematic front view showing one embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 1B] This is a schematic side view showing one embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 2A] This is a schematic front view showing another embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 2B] This is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 3] This is a schematic side view showing an example of the positional relationship between the heating element and the first liquid conduit. [Figure 4] This is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 5] This is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Figure 6] This is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspensions of the present invention. [Modes for carrying out the invention]

[0011] <Apparatus for adjusting the moisture content of pigment suspension and method for adjusting the moisture content of pigment suspension> The present invention will be further described in detail below with reference to preferred embodiments. The moisture content adjustment device for pigment suspension of the present invention (hereinafter also simply referred to as "moisture content adjustment device") is a device comprising a first tank, a heating element, and a first liquid conduit. The first tank is a part that contains a pigment suspension containing water. The heating element is a part positioned above the first tank that adheres to the pigment suspension and evaporates the water in the pigment suspension. The first liquid conduit is a part that supplies the pigment suspension in the first tank so that it adheres to the heating element. The moisture content adjustment device of the present invention further comprises a liquid receiver positioned between the heating element and the first tank, such that its lower end contacts the pigment suspension in the first tank, which guides the pigment suspension that did not adhere to the heating element into the first tank. The moisture content of the pigment suspension is then adjusted by circulating the pigment suspension between the first tank and the heating element. Furthermore, the method for adjusting the moisture content of pigment suspension of the present invention (hereinafter also simply referred to as "moisture content adjustment method") is a method for adjusting the moisture content of a pigment suspension using the above-described moisture content adjustment device. The details of the moisture content adjustment device and moisture content adjustment method of the present invention will be described below with reference to the drawings.

[0012] (Embodiments 1 and 2) Figure 1A is a schematic front view showing one embodiment of the pigment suspension moisture content adjustment device of the present invention, and Figure 1B is a schematic side view showing one embodiment of the pigment suspension moisture content adjustment device of the present invention. Furthermore, Figure 2A is a schematic front view showing another embodiment of the pigment suspension moisture content adjustment device of the present invention, and Figure 2B is a schematic side view showing another embodiment of the pigment suspension moisture content adjustment device of the present invention. Moisture content adjustment device (I) 1A shown in Figures 1A and 1B, and moisture content adjustment device (II) 1B shown in Figures 2A and 2B, both include a vertically arranged disc-shaped heating element 2 for adjusting the moisture content in the pigment suspension. The heating element 2 is connected to a drive source 4 via a drive shaft 3 and is configured to rotate around the drive shaft 3. Near both sides of the disc-shaped heating element 2, first liquid conduits 5 are provided for discharging and adhering the pigment suspension toward both sides of the heating element 2 (Figure 3). A scraper 9 is provided on the front side of the heating element 2 in the direction of rotation to remove the pigment suspension (wet cake) after moisture content adjustment from the surface of the heating element 2. Below the scraper 9, a recovery container 10 for collecting the wet cake removed from the surface of the heating element 2 and a chute 11 for guiding the wet cake into the recovery container 10 are provided. Directly below the discharge port of the first liquid conduit 5, a first tank 6 is provided for containing the pigment suspension that did not adhere to the heating element 2.

[0013] The first tank 6 is equipped with a level sensor 13 for detecting the water level (amount of pigment suspension contained) in the first tank 6, and a first stirrer 12 for stirring the pigment suspension. Liquid receivers 7 and 37 are positioned between the heating element 2 and the first tank 6 to guide any pigment suspension that did not adhere to the heating element 2 into the first tank 6. Both liquid receivers 7 and 37 are positioned so that their lower ends are in contact with the pigment suspension in the first tank 6. By providing such liquid receivers 7 and 37, foaming that occurs at the liquid surface of the pigment suspension in the first tank 6 can be suppressed.

[0014] In the water content adjusting device (I) 1A and the water content adjusting device (II) 1B, the pigment suspension discharged from the first liquid conduit 5 is made to adhere (contact) to the surface (left and right side surfaces) of the heating body 2 rotated by the power of the drive source 4. After adjusting the water content of the pigment suspension adhered by the heat on the surface of the heating body 2, the formed wet cake is peeled off from the surface of the heating body 2 by the scraper 9. The peeled wet cake is collected in the collection container 10 via the shooter 11. On the other hand, among the liquid pigment suspension discharged from the first liquid conduit 5 toward the surface of the heating body 2, the pigment suspension that did not adhere to the heating body 2 is accommodated in the first tank 6 through the liquid receivers 7 and 37. In order to make the concentration of the pigment suspension uniform, the pigment suspension in the first tank 6 is stirred by the first stirrer 12 at a speed that does not cause foaming.

[0015] Regarding the reason why the provision of the liquid receiver makes it possible to suppress the foaming occurring on the liquid surface of the pigment suspension in the first tank, the inventors of the present invention have speculated as follows. The main causes of the foaming occurring on the liquid surface of the pigment suspension in the first tank as the treatment progresses are considered to be the following (i) and (ii). (i) When the pigment suspension that did not adhere to the heating body directly falls onto the pigment suspension liquid surface in the first tank from a predetermined height, it entrains the surrounding air. (ii) A large amount of pigment is adsorbed onto the generated bubbles, making it difficult to break the bubbles.

[0016] That is, since the pigment is hydrophobic, it easily adheres to the bubbles and has a high affinity with the entrained air. Thus, it is considered that foaming occurs on the liquid surface of the pigment suspension in the first tank as the treatment progresses. Based on such speculation, the inventors of the present invention provided a liquid receiver for guiding the pigment suspension that did not adhere to the heating body into the first tank between the heating body and the first tank. Further, the liquid receiver was arranged such that the lower end (discharge end) of the liquid receiver contacts the pigment suspension in the first tank. Thereby, it has become possible to suppress the foaming occurring on the liquid surface of the pigment suspension in the first tank.

[0017] It is also conceivable to reduce the distance between the heating body and the first tank disposed below the heating body and lower the predetermined height (the height at which the pigment suspension falls) to mitigate the impact generated when the pigment suspension falls. However, when the pigment suspension that did not adhere to the heating body is collected into the first tank, the temperature of the pigment suspension in the first tank rises, and gradually steam is generated. Therefore, if the distance between the heating body and the first tank is reduced, the generated steam adheres to the heating body, causing uneven drying and making it easier for unevenness to occur in the moisture content of the formed wet cake.

[0018] The distance from the location where the pigment suspension of the heating body 2 drops to the liquid receivers 7 and 37 may be within a range where the heating body 2 does not contact the liquid receivers 7 and 37. Specifically, it is preferably 200 cm or less, more preferably 150 cm or less, and particularly preferably 100 cm or less.

[0019] The shape of the liquid receiver may be any shape that can guide the pigment suspension that did not adhere to the heating body to the first tank. Examples of the shape of the liquid receiver include an inclined flat plate shape (the liquid receiver 37 in FIGS. 1A and 1B), a funnel shape (the liquid receiver 7 in FIGS. 2A and 2B), and a spherical shape. The shape of the liquid receiver is preferably an inclined flat plate shape (the liquid receiver 37) or a funnel shape (the liquid receiver 7) rather than a spherical shape because the pigment suspension can be guided along these shapes to the liquid surface in the first tank 6, further suppressing the generation of foaming. Note that two or more liquid receivers may be provided. When two or more liquid receivers are provided, at least the lower end (discharge end) of one liquid receiver may be arranged to contact the pigment suspension in the first tank.

[0020] The diameter of the lower end (discharge end) of the funnel-shaped liquid receiver 7 is preferably as small as possible. By using a funnel-shaped liquid receiver 7 with a small diameter at the lower end (discharge end), the generation of foam caused by the impact of the dropped pigment suspension can be further suppressed. The diameter (inner diameter) of the lower end (discharge end) of the funnel-shaped liquid receiver 7 is preferably 25 cm or less, and more preferably 18 cm or less. Furthermore, a diameter of 12 cm or less is particularly preferable because it reduces the amount of liquid per unit time, further mitigates the impact of the drop, and further suppresses the generation of foam.

[0021] The angle between the inclined flat liquid receiver 37 and the liquid surface of the pigment suspension in the first tank 6 is preferably 0° to 90°, and more preferably 20° to 70°. Furthermore, an angle of 30° to 60° is particularly preferable because it provides a good balance between the distance from where the pigment suspension falls to the liquid receiver 37 and the speed at which the pigment suspension flows along the incline of the liquid receiver 37, thereby further suppressing foaming.

[0022] A pigment suspension is a so-called aqueous suspension containing water and a pigment. Inorganic or organic pigments can be used as the pigment. Any conventionally known organic pigment can be used. Examples of organic pigments include azo pigments, quinacridone pigments, anthraquinone pigments, diketopyrrolopyrrole pigments, quinophthalone pigments, methine / azomethine pigments, phthalocyanine pigments, perylene pigments, perinone pigments, and isoindolinone pigments. More specific examples of organic pigments include CIPigment Blue 15:3, CIPigment Yellow 74, CIPigment Violet 19, and CIPigment Red 122. Among these, CIPigment Yellow 74 is particularly effective when used with the present invention because it has higher hydrophobicity than other organic pigments, causing the pigment suspension to foam easily.

[0023] (Embodiment 3) Figure 4 is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspension of the present invention. The moisture content adjustment device (III) 30 shown in Figure 4 includes a plate-type heat exchanger 14, which is a cooling means for cooling the pigment suspension to be attached to the heating element 2. The heat flow rate of the plate-type heat exchanger 14 is designed to be, for example, 29 kW or more. The plate-type heat exchanger 14 is installed in the middle of the first liquid conduit 5 at a location that does not obstruct the rotation of the heating element 2 or the discharge of the pigment suspension from the first liquid conduit 5 to the heating element 2. The pigment suspension, which has been circulated and whose temperature has risen, enters the plate-type heat exchanger 14 via the circulation pump 8 from the first tank 6 through the first liquid conduit 5. The plate-type heat exchanger 14 has a flow path formed by bolting together a plurality of thin corrugated metal plates via gaskets. The plate-type heat exchanger 14 is also provided with a cooling water inlet 15 and a cooling water outlet 16, and is configured to allow heat exchange by the inflow and outflow of cooling water at a temperature of approximately 5 to 25°C. The pigment suspension that enters the plate heat exchanger 14 is cooled as heat is transferred as it flows through the flow path within the plate heat exchanger 14. The cooled pigment suspension flows through the first liquid conduit 5 and is discharged to the heating element 2. The pigment suspension in the first tank 6 is stirred by the first agitator 12 at a speed that does not cause foaming in order to suppress the occurrence of temperature and concentration unevenness.

[0024] When the pigment suspension that did not adhere to the heating element 2 returns to the first tank 6, the temperature of the pigment suspension in the first tank 6 rises, causing the bubbles generated at the liquid surface in the first tank 6 to expand due to thermal expansion. The moisture adjustment device (III) 30 is equipped with a cooling means such as a plate heat exchanger 14, which suppresses the rise in temperature of the pigment suspension in the first tank 6 and thus suppresses the increase in bubbles due to thermal expansion.

[0025] As a cooling means, at least one selected from the group consisting of ice, coolants, jacketed heat exchangers, immersion heat exchangers, and plate heat exchangers can be mentioned. From the viewpoint of thermal conductivity, it is preferable to use a plate heat exchanger. The cooling means may be provided at a location other than in the middle of the first liquid conduit. For example, a jacketed tank type heat exchanger may be attached to the first tank, or an immersion heat exchanger may be placed inside the first tank. In addition, two or more cooling means may be provided.

[0026] (Embodiment 4) Figure 5 is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspension of the present invention. The moisture content adjustment device (IV) 31 shown in Figure 5 comprises a second tank 17 for containing an antifoaming liquid containing an antifoaming agent, and a second liquid conduit 19 that connects the second tank 17 and the first tank 6 and supplies the antifoaming liquid into the first tank 6. The second tank 17 is provided with a second stirrer 20 for stirring the antifoaming liquid. The second liquid conduit 19 is provided with a first supply pump 18 for pressurizing the antifoaming liquid from the second tank 17 to the first tank 6. The end of the second liquid conduit 19 on the first tank 6 side is connected at a position lower than the liquid level of the pigment suspension in the first tank 6.

[0027] When the liquid level of the pigment suspension contained in the first tank 6 drops, the defoaming liquid that has flowed out from the bottom of the second tank 17 is supplied to the first tank 6 through the second liquid conduit 19. The end of the second liquid conduit 19 on the first tank 6 side (discharge port) is located at a lower position than the liquid level of the pigment suspension in the first tank 6. By positioning the end of the second liquid conduit 19 (discharge port) at a lower position than the liquid level of the pigment suspension in the first tank 6, the supplied defoaming liquid is easily diffused into the pigment suspension by the operation of the first stirrer 12. This makes it possible to efficiently bring the foam generated at the liquid surface of the pigment suspension in the first tank 6 into contact with the defoaming agent, making it easier to defoam the generated foam. The defoaming liquid in the second tank 17 is stirred by the second stirrer 20 at a speed that does not cause foaming in order to suppress the occurrence of uneven concentration.

[0028] (Embodiment 5) Figure 6 is a schematic side view showing another embodiment of the moisture content adjustment device for pigment suspension of the present invention. The moisture content adjustment device (V)32 shown in Figure 6 comprises a third tank 21 for containing an antifoaming liquid containing an antifoaming agent, a third liquid conduit 23 for supplying the antifoaming liquid in the third tank 21 into the first tank 6, and a fourth tank 24 for containing the pigment suspension. Furthermore, the moisture content adjustment device (V)32 comprises a fourth liquid conduit 26 for replenishing the pigment suspension in the fourth tank 24 into the first tank 6, and a level switch 28 which is a foam detection means for detecting foam generated on the liquid surface of the pigment suspension in the first tank 6.

[0029] The third liquid conduit 23 is equipped with a second supply pump 22 for pressurizing the defoaming liquid from the third tank 21 to the first tank 6. The end of the third liquid conduit 23 on the first tank 6 side (discharge port) is connected to the top of the first tank 6 and is configured to spray the defoaming liquid radially onto the pigment suspension in the first tank 6. The fourth liquid conduit 26 is equipped with a third supply pump 25 for pressurizing the pigment suspension from the fourth tank 24 to the first tank 6. The end of the fourth liquid conduit 26 on the first tank 6 side (discharge port) is connected at a position lower than the liquid level of the pigment suspension in the first tank 6. The fourth tank 24 is equipped with a third stirrer 27 for stirring the pigment suspension.

[0030] When the liquid level of the pigment suspension in the first tank 6 drops and the amount of pigment suspension becomes insufficient, the required amount of pigment dispersion is supplied from the bottom of the fourth tank 24 through the fourth liquid conduit 26 to the first tank 6 from a position lower than the liquid level of the pigment suspension. When bubbles generated on the liquid surface of the pigment suspension touch the level switch 28, which is a bubble detection means, the second supply pump 22 is activated. As a result of the activation of the second supply pump 22, the defoaming liquid in the third tank 21 is sent to the first tank 6 through the third liquid conduit 23. The sent defoaming liquid is then sprayed radially towards the generated bubbles from the end (discharge port) of the third liquid conduit 23, which is positioned higher than the level switch 28. By spraying the defoaming liquid radially from a position higher than the level switch 28, the defoaming liquid can be applied to the entire surface of the bubbles, effectively defoaming them.

[0031] The location of the level switch 28 in the first tank 6 is preferably within a range of 5 cm to 10 cm above the liquid surface before processing the pigment suspension (initial state). If the level switch 28 is placed less than 5 cm above the liquid surface, it is more likely to react immediately with the generated foam, making it easier to supply more defoaming liquid than necessary. On the other hand, if the level switch 28 is placed more than 10 cm above the liquid surface, it may be difficult to defoam sufficiently, and unevenness in the moisture content of the resulting wet cake may occur. The pigment suspension for replenishment in the fourth tank 24 is stirred by the third stirrer 27 at a speed that does not cause foaming in order to suppress the occurrence of uneven concentration.

[0032] This embodiment includes the following configurations and methods. (Configuration 1) A first tank containing a pigment suspension containing water, A heating element positioned above the first tank, to which the pigment suspension is attached and to which the water in the pigment suspension is evaporated, A device for adjusting the moisture content of a pigment suspension, comprising: a first liquid conduit for supplying the pigment suspension in the first tank so as to adhere to the heating element, Furthermore, a liquid receiver is provided, positioned between the heating element and the first tank such that its lower end contacts the pigment suspension in the first tank, to guide any pigment suspension that does not adhere to the heating element into the first tank. A device for adjusting the water content of a pigment suspension, characterized by circulating the pigment suspension between the first tank and the heating element to adjust the water content of the pigment suspension. (Configuration 2) Furthermore, the configuration includes a cooling means for cooling the pigment suspension to be attached to the heating element, The device for adjusting the moisture content of a pigment suspension according to configuration 1, wherein the cooling means is at least one selected from the group consisting of ice, a coolant, a jacket-type heat exchanger, an immersion-type heat exchanger, and a plate-type heat exchanger. (Configuration 3) Furthermore, a second tank containing an antifoaming liquid containing an antifoaming agent, The system comprises a second liquid conduit that connects the second tank and the first tank and supplies the defoaming liquid into the first tank, A device for adjusting the moisture content of a pigment suspension according to configuration 1 or 2, wherein the end of the second liquid conduit on the first tank side is connected to a position lower than the liquid level of the pigment suspension in the first tank. (Configuration 4) Furthermore, a third tank containing an antifoaming liquid containing an antifoaming agent, A third liquid conduit for supplying the defoaming liquid in the third tank into the first tank, A fourth tank containing the aforementioned pigment suspension, A fourth liquid conduit for replenishing the pigment suspension in the fourth tank into the first tank, A device for adjusting the moisture content of a pigment suspension according to configuration 1 or 2, comprising: a foam detection means for detecting foam generated on the liquid surface of the pigment suspension in the first tank. (Method 1) A first tank containing a pigment suspension containing water, A heating element positioned above the first tank, to which the pigment suspension is attached and to which the water in the pigment suspension is evaporated, A method for adjusting the moisture content of a pigment suspension, using a moisture content adjustment device for a pigment suspension comprising: a first liquid conduit for supplying the pigment suspension in the first tank so as to adhere to the heating element, The moisture content adjustment device further includes a liquid receiver positioned between the heating element and the first tank, such that its lower end contacts the pigment suspension in the first tank, for guiding the pigment suspension that did not adhere to the heating element into the first tank. A method for adjusting the water content of a pigment suspension, characterized by circulating the pigment suspension between the first tank and the heating element to adjust the water content of the pigment suspension. [Explanation of symbols]

[0033] 1A: Moisture adjustment device (I) 1B: Moisture adjustment device (II) 2: Heating body 3: Drive shaft 4: Power source 5: First liquid conduit 6: Tank 1 7: Liquid receiver 8: Circulation pump 9: Scraper 10: Collection container 11: Shooter 12: First agitator 13: Level Sensor 14: Plate heat exchanger 15: Cooling water inlet 16: Cooling water outlet 17: Tank No. 2 18: First supply pump 19: Second liquid conduit 20: Second agitator 21: Tank No. 3 22: Second supply pump 23: Third liquid conduit 24: Tank No. 4 25: Third supply pump 26: Fourth liquid conduit 27: Third agitator 28: Level switch 30: Moisture adjustment device (III) 31: Moisture adjustment device (IV) 32: Moisture adjustment device (V) 37: Liquid receiver

Claims

1. A first tank containing a pigment suspension containing water, A heating element positioned above the first tank, which is used to attach the pigment suspension and evaporate the water in the pigment suspension, A device for adjusting the moisture content of a pigment suspension, comprising: a first liquid conduit for supplying the pigment suspension in the first tank so as to adhere to the heating element, Furthermore, a liquid receiver is provided, positioned between the heating element and the first tank such that its lower end contacts the pigment suspension in the first tank, to guide any pigment suspension that does not adhere to the heating element into the first tank. A device for adjusting the water content of a pigment suspension, characterized by circulating the pigment suspension between the first tank and the heating element to adjust the water content of the pigment suspension.

2. Furthermore, the system includes a cooling means for cooling the pigment suspension to be attached to the heating element, The apparatus for adjusting the moisture content of a pigment suspension according to claim 1, wherein the cooling means is at least one selected from the group consisting of ice, a coolant, a jacket-type heat exchanger, an immersion-type heat exchanger, and a plate-type heat exchanger.

3. Furthermore, a second tank containing an antifoaming solution containing an antifoaming agent, The system comprises a second liquid conduit that connects the second tank and the first tank and supplies the defoaming liquid into the first tank, The moisture content adjustment device for a pigment suspension according to claim 1 or 2, wherein the end of the second liquid conduit on the first tank side is connected at a position lower than the liquid level of the pigment suspension in the first tank.

4. Furthermore, a third tank containing an antifoaming solution containing an antifoaming agent, A third liquid conduit supplies the defoaming liquid in the third tank into the first tank, A fourth tank containing the aforementioned pigment suspension, A fourth liquid conduit for replenishing the pigment suspension in the fourth tank into the first tank, A device for adjusting the moisture content of a pigment suspension according to claim 1 or 2, further comprising: a foam detection means for detecting foam generated on the liquid surface of the pigment suspension in the first tank.

5. A first tank containing a pigment suspension containing water, A heating element positioned above the first tank, which is used to attach the pigment suspension and evaporate the water in the pigment suspension, A method for adjusting the moisture content of a pigment suspension, using a moisture content adjustment device for a pigment suspension comprising: a first liquid conduit for supplying the pigment suspension in the first tank so as to adhere to the heating element, The moisture content adjustment device further includes a liquid receiver positioned between the heating element and the first tank, such that its lower end contacts the pigment suspension in the first tank, for guiding the pigment suspension that did not adhere to the heating element into the first tank. A method for adjusting the water content of a pigment suspension, characterized by circulating the pigment suspension between the first tank and the heating element to adjust the water content of the pigment suspension.

Images