Extrusion device, dehydration cylinder, dehydration method, and method for producing resin particles

Abstract

Provided is an extruding device, a dehydration cylinder, a dehydration method, and a method for producing resin particles. The problem to be solved is to remove moisture contained in a resin material discharged from a dehydration cylinder while preventing the dehydration cylinder from being discharged from a resin component. The means for solving the problem is an extruding device including a cylinder, a screw built in the cylinder, and a dehydration cylinder body (11b) provided in the middle of the cylinder and configured to discharge moisture separated from a resin material supplied into the cylinder. The dehydration cylinder body (11b) has a structure in which plate-like members (13) each having an opening portion through which the screw passes are arranged in a long axis direction of the cylinder. The surface roughness of opposing surfaces of the plurality of plate-like members (13) is greater than the surface roughness of an inner wall of the cylinder.

Description

Technical Field

[0001] This invention relates to extrusion apparatus, dewatering barrel, dewatering method, and method for manufacturing resin particles. Background Technology

[0002] For example, the technology related to the extrusion device has been described in Japanese Patent Publication No. 2001-129870 (Patent Document 1).

[0003] [Existing technical documents]

[0004] Patent documents

[0005] Patent document 1: Japanese Patent Publication No. 2001-129870. Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] Resin products, such as resin granules, can be manufactured using resin materials extruded from an extrusion device. In the case of manufacturing resin products using an extrusion device, the resin material is supplied into the barrel of the extrusion device, and the resin material is mixed, conveyed, and extruded from a die mounted at the front end of the barrel by a screw built into the barrel.

[0008] When the resin material supplied to the extrusion barrel contains a high proportion of moisture, and the moisture content of the resin material extruded from the extrusion unit is high, it becomes difficult to manufacture resin products such as resin granules using the resin material extruded from the extrusion unit. In this case, it is desirable to install a dehydration barrel in the middle of the extrusion unit barrel so that the moisture separated from the resin material transported from the barrel can be discharged from the dehydration barrel.

[0009] However, when water is discharged from the dewatering barrel, there is a concern that not only water but also resin components may be discharged along with it, which could cause problems. Therefore, it is desirable to selectively discharge the water contained in the resin material from the dewatering barrel while preventing the resin components from being discharged.

[0010] Other issues and novel features will become apparent from the description in this specification and from the accompanying drawings.

[0011] [Problem-solving methods]

[0012] According to one embodiment, the extrusion apparatus includes: a barrel, a screw housed within the barrel, and a dewatering barrel section for discharging water separated from resin material supplied to the barrel. The dewatering barrel section has a structure comprising a plurality of plate-shaped members arranged along the long axis of the barrel, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

[0013] According to one embodiment, the dehydration method includes: (a) a step of supplying a resin material containing moisture into a barrel; (b) a step of conveying the resin material through a screw inside the barrel; (c) a step of discharging moisture separated from the resin material from a dehydration barrel section disposed in the middle of the barrel; and (d) a step of extruding the resin material from a die connected to the front end of the barrel. The dehydration barrel section has a structure comprising a plurality of plate-shaped members arranged along the long axis of the barrel, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

[0014] [Invention Effects]

[0015] According to one embodiment, while the moisture contained in the resin material can be discharged from the dewatering barrel, the discharge of resin components from the dewatering barrel can be suppressed or prevented. Attached Figure Description

[0016] Figure 1 This is an explanatory diagram showing an example of the configuration of an extrusion apparatus according to one embodiment.

[0017] Figure 2 It is shown schematically. Figure 1 An extrusion apparatus barrel structure diagram.

[0018] Figure 3 This is a side view of the dewatering barrel of an extrusion apparatus according to one embodiment.

[0019] Figure 4 This is a plan view of the dewatering barrel of an extrusion apparatus according to one embodiment.

[0020] Figure 5 This is a cross-sectional view of the dewatering barrel of an extrusion apparatus according to one embodiment.

[0021] Figure 6 It is shown Figures 3-5 The diagram shows a plan view of the plate-shaped component used in the dehydration machine barrel.

[0022] Figure 7 yes Figure 6 A cross-sectional view of the plate-like member shown.

[0023] Figure 8 yes Figure 6 A cross-sectional view of the plate-like member shown.

[0024] Figure 9 yes Figure 6 A cross-sectional view of the plate-like member shown.

[0025] Figure 10 It is a cross-sectional view showing multiple plate-shaped components arranged along the long axis of the barrel.

[0026] Figure 11 It is an enlarged representation Figure 10 A partially enlarged sectional view.

[0027] Figure 12 This is a plan view showing a modified example of the barrel of a dewatering machine.

[0028] Figure 13 This is a cross-sectional view showing a modified example of the barrel of a dewatering machine.

[0029] The annotations in the attached figures are explained as follows:

[0030] 1. Extrusion device

[0031] 2. Machine barrel

[0032] 3 screws

[0033] 4 Rotary drive mechanism

[0034] 5 hoppers

[0035] 6. Mold

[0036] 7. Resin materials

[0037] 8 Pelletizers

[0038] 8a Cutter

[0039] 9 particles

[0040] 10 Pressure section

[0041] 11, 11a, 11b Machine barrel

[0042] 12. Opening

[0043] 13. Plate-shaped members

[0044] 13a Protrusion

[0045] 14. Opening

[0046] 15 Fixed components

[0047] 16 Fixing Plates

[0048] 17 gaps

[0049] 21 Cover components

[0050] 22 Opening

[0051] A-A line

[0052] B-B line

[0053] C-C line

[0054] D-D line

[0055] H1 protrusion amount

[0056] X, Y, Z directions Detailed Implementation

[0057] The embodiments will now be described in detail based on the drawings. Furthermore, in all the drawings used to explain the embodiments, components with the same function are marked with the same symbols, and repeated descriptions are omitted. Also, in the following embodiments, unless specifically necessary, descriptions of the same or similar parts will generally not be repeated.

[0058] (Implementation Method)

[0059] <Extrusion Equipment>

[0060] Figure 1 This is an explanatory diagram (side view) showing an example of the configuration of the extrusion apparatus (extruder) 1 according to this embodiment. Figure 2 This is a schematic diagram (plan perspective view) illustrating the structure inside the barrel 2 of the extrusion device 1. Figure 2 Mid-perspective shows when viewed from above Figure 1 When the extrusion device 1 is shown, the screw 3 is arranged inside the barrel 2.

[0061] First, refer to Figure 1 This section describes the general structure of the extrusion device 1. Figure 1 The extrusion apparatus 1 shown includes: a barrel 2, two screws 3 rotatably disposed within the barrel 2, a rotary drive mechanism 4 for rotating the screws 3 within the barrel 2, a hopper (material feeding section, material supply section) 5 disposed on the upstream side of the barrel 2, and a die (cavity, mold) 6 mounted on the downstream front end of the barrel 2. The hopper 5 is connected to the top of the barrel 2, allowing resin material (raw material, aqueous polymer) 7 to be supplied into the barrel 2 through the hopper 5.

[0062] Furthermore, when referring to the barrel 2 and screw 3 as the "downstream side" and "upstream side," "downstream side" means the side downstream of the resin material flow within the barrel 2, and "upstream side" means the side upstream of the resin material flow within the barrel 2. Therefore, in the barrel 2 and screw 3, the side closer to the front end of the barrel 2 is the downstream side, and the side farther from the front end of the barrel 2 is the upstream side. Also, the front end of the barrel 2 corresponds to the end of the resin material extrusion side within the barrel 2, that is, the end connected to the mold 6.

[0063] Two screws 3 are rotatably inserted and housed inside the barrel 2. Therefore, the extrusion unit 1 can also be considered a twin-screw extrusion unit. Inside the barrel 2, the two screws 3 are configured to mesh and rotate. The long axis of the barrel 2 is the same as the long axis of the screws 3 inside the barrel 2, which is the X direction in this case. Furthermore, the long axis of the barrel 2 is the direction of its long side or length, and the cylindrical barrel 2 extends along the X direction, which is the direction of its long axis. Also, the long axis of the screws 3 corresponds to the axial direction of the rotation axis of the screws 3. Inside the barrel 2, resin material is conveyed from the upstream side to the downstream side by the rotating screws 3 along the X direction, which is the direction of their long axis.

[0064] Furthermore, the X, Y, and Z directions are displayed on each drawing as needed. The X, Y, and Z directions intersect each other, and more specifically, they are orthogonal. Therefore, the X and Y directions are orthogonal, and the Z direction is orthogonal to both the X and Y directions. The X and Y directions correspond to the horizontal direction, and the Z direction corresponds to the vertical direction (height). The X direction is the major axis of the barrel 2, and therefore, it is also the major axis of the screw 3 inside the barrel 2.

[0065] Furthermore, in this embodiment, the case where there are two screws 3 inside the barrel 2 is described. However, in other embodiments, the number of screws 3 inside the barrel 2 may be set to one. However, when the number of screws 3 inside the barrel 2 is set to two, the space volume increases. Therefore, for the same screw diameter, the case with two screws 3 is better than the case with one screw 3, which can improve the resin material supply capacity.

[0066] The barrel 2 is composed of multiple barrel bodies (barrel sections) 11, which are arranged and connected from the upstream side to the downstream side (here, the X direction). Among the multiple barrel bodies 11 constituting the barrel 2, the barrel body 11a connected to the hopper 5 has an opening on its upper surface and is connected to the hopper 5 in a manner that communicates with the opening. Thus, the resin material 7 fed into the hopper 5 is supplied into the barrel body 11a through the opening on its upper surface.

[0067] Furthermore, the plurality of barrel bodies 11 constituting the barrel 2 includes a dewatering barrel body (dewatering barrel) 11b. The dewatering barrel body 11b is disposed in the middle of the barrel 2. That is, the dewatering barrel body 11b is disposed in the middle of the plurality of barrel bodies 11 arranged in a direction from the upstream side to the downstream side. In the barrel 2, the dewatering barrel body 11b is disposed further downstream of the barrel body 11a to which the hopper 5 is connected. The dewatering barrel body 11b can be used as a discharge section to discharge the water separated from the resin material 7 supplied into the barrel 2 to the outside of the barrel 2.

[0068] exist Figure 1 The diagram shows the case where the extrusion device 1 has two dewatering barrels 11b, which are arranged at two points in the middle of the barrel 2. However, the number of dewatering barrels 11b in the extrusion device 1 can be changed as needed and can be set to any number of more than one.

[0069] Secondly, for Figure 1 The operation of the extrusion device 1 shown will be explained in summary.

[0070] Resin material 7 containing moisture is supplied from hopper 5 into barrel 2. The resin material 7 supplied to barrel 2 contains moisture and resin components (solid components). The resin material supplied from hopper 5 into barrel 2 is conveyed forward (downstream) within barrel 2 by a rotating screw 3. At this time, the resin material is kneaded by the rotating screw 3. Midway through the conveying of the resin material within barrel 2, moisture is separated from the resin material, and the separated moisture is discharged to the outside from the dewatering barrel body 11b. The resin material (resin material with reduced moisture content) conveyed within barrel 2 and reaching the front end of barrel 2 is discharged from the outlet of mold 6. Because the moisture contained in the resin material is discharged to the outside from the dewatering barrel body 11b, the moisture content of the resin material discharged from the outlet of mold 6 is lower than the moisture content of the resin material 7 in the stage from hopper 5 into barrel 2. The front surface of mold 6, i.e., the side opposite to the side connected to barrel 2, is connected to pelletizer 8. The resin material extruded from the outlet of the mold 6 is cut one by one by the cutter (cutting blade) 8a of the pelletizing machine 8 while being cooled and solidified. Thus, granules 9 are formed into resin granules. Afterwards, the granules 9 are transported to the outside of the pelletizing machine 8, such as to a dryer. In this way, granules 9 can be obtained using the extrusion apparatus 1 of this embodiment. For example, by mixing these granules 9 with functional fillers or the like as secondary raw materials, functional granules with added value can be obtained. Various resin products can be manufactured using these functional granules.

[0071] like Figure 2As shown, the barrel 2 of the extrusion device 1 and the screw 3 inside the barrel 2 have the X-direction as their major axis. The screw 3 can be configured as needed by combining a screw section that rotates to feed the conveyed material forward at a first speed, a screw section that rotates to feed the conveyed material forward at a speed lower than the first speed, a screw section that rotates to push the conveyed material backward, and a screw section configured to prevent the conveyed material from being conveyed forward. By combining these various screw sections, the screw 3 is configured to apply pressure to the conveyed material using a portion inside the barrel 2 (pressure section 10).

[0072] The dewatering barrel 11b is positioned upstream of the pressure section 10. The resin material conveyed inside the barrel 2 is separated from the water and resin components by the pressure section 10. The resin components are squeezed out downstream of the pressure section 10, and the water is discharged from the dewatering barrel 11b to the outside of the barrel 2.

[0073] exist Figure 2 In the example shown, the pressure unit 10 and the dewatering barrel 11b are respectively located at two positions in the X direction. However, from Figure 1 Most of the water contained in the resin material 7 inside the barrel 2 is supplied to the hopper 5 shown, and discharged from the initial dewatering barrel body 11b to the outside of the barrel 2.

[0074] Therefore, the process of manufacturing granules 9 using the extrusion apparatus 1 includes: supplying a resin material (7) containing moisture into the barrel 2; conveying the resin material using the screw 4 inside the barrel 2; discharging the moisture separated from the resin material from the dehydration barrel section 11b located in the middle of the barrel 2; and extruding the resin material from the die 6 connected to the front end of the barrel 2. The process of manufacturing granules 9 using the extrusion apparatus 1 further includes a step of cutting the resin material extruded from the die 6 to form granules 9.

[0075] <The Process of Self-Reflection>

[0076] The resin material supplied to the barrel of the extrusion unit may contain a high proportion of moisture. However, when the moisture content of the resin material extruded from the extrusion unit is high, it becomes difficult to manufacture resin products such as resin granules using the material extruded from the extrusion unit. Therefore, when the moisture content of the resin material supplied to the barrel of the extrusion unit is high, it is preferable to provide a dehydration barrel (corresponding to the dehydration barrel body 11b) in the middle of the barrel of the extrusion unit, so that moisture is separated from the conveyed resin material inside the barrel, and the separated moisture is discharged from the dehydration barrel.

[0077] For example, the manufacture of polymers such as rubber polymers is generally carried out through emulsion polymerization, solution polymerization, etc., but in the final stage of these processes, the polymer becomes a slurry containing water. A coagulant is added to this slurry to agglomerate the microparticles dispersed in the slurry into a certain degree of agglomeration, and then the agglomerated particles are separated from the liquid. These agglomerated particles (polymer aggregates, water-containing debris) can be used as resin material (corresponding to resin material 7) fed into the hopper of the extrusion apparatus. In this case, the particles used as resin material fed into the hopper contain water and resin components, resulting in a state with a high water content. For example, the resin material in the stage of being fed into the hopper contains, for example, about 30 to 50% water. On the other hand, the water content of the resin material extruded from the extrusion apparatus is preferably, for example, less than 1%. Furthermore, the water content is expressed as a percentage by weight (%).

[0078] Therefore, when a dewatering barrel is installed in the barrel of an extrusion unit, it is desirable that the moisture contained in the resin material can be effectively removed from the dewatering barrel.

[0079] However, when dehydration is performed using a dehydration barrel, there is a risk that not only water but also resin components may be discharged to the outside of the dehydration barrel. When resin components are discharged from the dehydration barrel, the proportion of resin components included in the resin material supplied to the extrusion barrel decreases. This leads to an increase in the manufacturing cost of resin products such as resin granules. Furthermore, when resin components are discharged from the dehydration barrel, they may accumulate in the water drainage channels of the dehydration barrel, potentially causing blockages. To prevent this, frequent cleaning of the dehydration barrel is necessary. This reduces the operating rate of the extrusion unit.

[0080] Therefore, when a dewatering barrel is provided in the barrel of an extrusion apparatus, it is desirable to selectively discharge the moisture contained in the resin material while inhibiting the discharge of resin components.

[0081] <Dehydrator barrel>

[0082] Figure 3 This is a side view showing a portion of the extrusion apparatus 2 according to this embodiment. Figure 4 This is a plan view (top view) showing a portion of the extrusion apparatus 2 according to this embodiment. Figure 5 This is a cross-sectional view of the extrusion apparatus 2 according to this embodiment. Figure 3 as well as Figure 4 The image shows a side view and a plan view of the dewatering machine barrel 11b. Figure 3 as well as Figure 4 The cross-sectional view at the location of line A-A shown in the figure roughly corresponds to Figure 5 . Figure 6To show the plan view of the plate-shaped member 13 used in the dehydration machine cylinder 11b, a plan view of the plate-shaped member 13 as viewed from the X direction is shown. Figures 7-9 A cross-sectional view showing the plate-shaped member 13 used in the dewatering machine barrel 11b. Figure 6 The cross-sectional view at the location of line B-B shown in the figure roughly corresponds to Figure 7 , Figure 6 The cross-sectional view at the location of the C-C line shown in the figure roughly corresponds to Figure 8 , Figure 6 The cross-sectional view at the location of the D-D line shown in the figure roughly corresponds to Figure 9 . Figure 10 To show a cross-sectional view of the plurality of plate-shaped members 13 arranged along the long axis of the barrel 2, a view corresponding to... Figure 7 A cross-sectional view of the section shown. Figure 11 It is an enlarged representation Figure 10 A partially enlarged sectional view.

[0083] In the extrusion apparatus 1 of this embodiment, a dehydration barrel body (dehydration barrel) 11b is provided in the middle of the barrel 2. The water contained in the resin material 7 supplied from the hopper 5 into the barrel 2 can be discharged to the outside of the barrel 2 through the dehydration barrel body 11b.

[0084] Reference Figures 3 to 11 The structure of the dewatering machine barrel 11b will be described below. The dewatering machine barrel 11b has a structure in which multiple plate-shaped members 13, through which the screw 3 passes, are arranged in the X direction, which is the long axis of the barrel 2. That is, the dewatering machine barrel 11b has multiple plate-shaped members 13 arranged in the long axis (X direction) of the barrel 2. The plate-shaped members 13 are preferably made of a metal material, such as stainless steel.

[0085] The plate-shaped member 13 has an opening 12 through which the screw 3 passes. Since the multiple plate-shaped members 13 are arranged along the X direction, which is the long axis of the barrel 2, the openings 12 of the multiple plate-shaped members 13 are connected to each other in the X direction. That is, the multiple plate-shaped members 13 are arranged in the X direction with their openings 12 connected to each other. By arranging multiple plate-shaped members 13, each having an opening 12, a barrel-shaped barrel section (barrel body 11b) is formed.

[0086] The screw 3 passes through the space formed by connecting the openings 12 of a plurality of plate-shaped members 13. Therefore, the plurality of plate-shaped members 13 arranged along the X direction cover the periphery of the screw 3. The openings 12 of each of the plurality of plate-shaped members 13 preferably have the same shape (planar shape) and the same size (planar size). Furthermore, the plurality of plate-shaped members 13 preferably have the same shape and the same size.

[0087] Figure 5 as well as Figure 6 Assuming there are two screws 3, the opening 12 has two overlapping circular portions. Furthermore, Figure 5 as well as Figure 6 In this case, the distance L1 from the periphery of the plate-shaped member 13 to the opening 12 is approximately constant. In other words, the planar shape of the plate-shaped member 13 is a shape that is approximately constant from the periphery of the plate-shaped member 13 to the opening 12 over a distance L1. This distance L1 can be set as needed, for example, it can be made to be about 10 mm. Furthermore, the plate-shaped member 13 is a thin member, and the thickness of the plate-shaped member 13 is preferably about 0.5 to 5 mm, for example, about 1 mm. The thickness direction of the plate-shaped member 13 is the X direction. The thickness of the plate-shaped member 13 described here corresponds to the thickness of the area other than the protrusion 13a described later.

[0088] Multiple plate-shaped members 13 arranged along the X direction are fixed to a fixed plate 16 by fastening members 15 such as screws or bolts. Therefore, in addition to an opening 12 through which a screw 3 passes, each plate-shaped member 13 also has an opening 14 through which a fastening member 15 such as a screw passes. The fixed plate 16 is a metal member that is thicker and stronger than the plate-shaped members 13, and has an opening communicating with the opening 12 of the plate-shaped members 13. Therefore, the dehydration machine barrel 11b has a structure in which multiple plate-shaped members 13 arranged along the X direction are sandwiched between a pair of fixed plates 16 separated along the X direction. The fixed plate 16 is preferably made of a metal material, such as stainless steel.

[0089] The space formed by connecting the openings 12 of multiple plate-shaped members 13 in the X direction, i.e., the conveying space of the dehydration machine barrel 11b, is through which the screw 3 passes and through which the resin material is conveyed by the rotating screw 3. Hereinafter, the space formed by connecting the openings 12 of multiple plate-shaped members 13 in the X direction is referred to as the conveying space of the dehydration machine barrel 11b. The shape and size of the cross-section (the cross-section perpendicular to the X direction) of the conveying space of the dehydration machine barrel 11b roughly correspond to the planar shape and size of the openings 12. The inner walls of the openings 12 of the multiple plate-shaped members 13 arranged along the X direction constitute the inner walls of the conveying space of the dehydration machine barrel 11b. Furthermore, in the barrel 11 other than the dehydration machine barrel 11b, the space through which the resin material through which the screw 3 passes and is conveyed by the rotating screw 3 is referred to as the conveying space of that barrel 11. The conveying space of the upstream side of the dewatering machine barrel 11b, the conveying space of the dewatering machine barrel 11b, and the conveying spaces of the upstream and downstream sides of the dewatering machine barrel 11b are connected in the X direction, and the shape and size of their cross sections (cross sections perpendicular to the X direction) can be approximately the same.

[0090] The resin material supplied from the hopper 5 into the barrel 2 is transported downstream by the rotation of the screw 3 within the barrel 2. At this time, the resin material is transported from the transport space of the barrel 11 on the upstream side of the dewatering barrel 11b, through the transport space of the dewatering barrel 11b, to the transport space of the barrel 11 on the downstream side of the dewatering barrel 11b.

[0091] In the dehydration barrel 11b, water separated from the resin material can be discharged to the outside through the spaces between the opposing surfaces of the plurality of plate-shaped members 13. That is, water separated from the resin material conveyed within the barrel 2 by the rotating screw 3 can be discharged to the outside through the gap 17 between the opposing surfaces of the plurality of plate-shaped members 13. This gap 17 serves as a slit for discharging water separated from the resin material and as a flow path (discharge passage) for the water separated from the resin material.

[0092] Here, the water separated from the resin material can be discharged through the gap 17 between the plurality of plate-shaped members 13, but the resin components contained in the resin material are preferably not discharged through the gap 17 between the plurality of plate-shaped members 13 as much as possible. That is, preferably in the dewatering barrel 11b, the water separated from the resin material is selectively discharged between the opposing surfaces of the plurality of plate-shaped members 13.

[0093] Moisture is expelled from gap 17, but to prevent the resin component from being expelled, increasing the static pressure (resistance to fluid flow through gap 17) of gap 17 is effective. This is because when the static pressure of gap 17 is high, compared to moisture, the relatively higher viscosity resin component will not penetrate into gap 17, while the lower viscosity moisture selectively penetrates into gap 17.

[0094] Therefore, in this embodiment, the surface roughness of the opposing surfaces (surfaces opposite to the X direction) of the plurality of plate-shaped members 13 arranged along the X direction becomes coarser (see reference). Figure 11 That is, roughening treatment is applied to the opposing surfaces of the multiple plate-shaped members 13. This increases the static pressure of the gap 17.

[0095] If the surface roughness of the opposing surfaces of the plurality of plate-like members 13 is low, the distance (spacing) between the opposing surfaces of the plurality of plate-like members 13 is almost constant regardless of their position within the surface. On the other hand, when the surface roughness of the opposing surfaces of the plurality of plate-like members 13 is roughened, numerous minute irregularities are reflected on the roughened surface, and the distance between the opposing surfaces of the plurality of plate-like members 13 becomes scattered depending on their position within the surface (see reference). Figure 11 ).

[0096] Because the surface roughness of the opposing surfaces of the multiple plate-shaped members 13 is coarse (roughened), the cross-sectional area of ​​the gaps 17 between the opposing surfaces of the multiple plate-shaped members 13, which serve as the flow path for water, varies considerably. Therefore, when the opposing surfaces of the multiple plate-shaped members 13 are roughened (the surface roughness is coarse), the static pressure of the gaps 17, which serve as the water drainage path, increases compared to the case where they are not roughened (the surface roughness is low). As described above, when the static pressure of the gaps 17 is high, the resin component with a relatively higher viscosity will not permeate the gaps 17, while the water with a lower viscosity will selectively permeate into the gaps 17. As a result, water separated from the resin material can be drained from the gaps 17 to the outside while preventing the resin components contained in the resin material from leaking to the outside through the gaps 17.

[0097] When the surface roughness of the opposing surfaces of multiple plate-shaped members 13 is expressed as the arithmetic mean roughness Ra, it is preferably 1.6a to 25a (more than 1.6a and less than 25a). The arithmetic mean roughness Ra can be measured as follows: First, the unevenness of the surface within the measurement interval (length) to which the object is located is measured. Second, using the average value of the measured unevenness as a reference line, the difference between the reference line and the unevenness curve is integrated along the measurement interval. The value of this integral result divided by the length of the measurement interval is the arithmetic mean roughness Ra.

[0098] Furthermore, while the opposing surfaces of the plurality of plate-shaped members 13 constituting the dewatering barrel 11b are roughened, the inner wall (inner surface) of the barrel 2 (barrel 11) is not roughened, and the surface roughness of the inner wall of the barrel 2 is lower than that of the opposing surfaces of the plurality of plate-shaped members 13. This is because the inner wall of the barrel 2 forms the inner wall of the space in which the resin material is transported by the rotating screw 3, and it is appropriate not to roughen it to avoid adversely affecting the transport of the resin material. Therefore, in this embodiment, the surface roughness of the opposing surfaces of the plurality of plate-shaped members 13 constituting the dewatering barrel 11b is greater than the surface roughness of the inner wall of the barrel 2. Here, the surface roughness of the inner wall of the barrel 2 corresponds to the surface roughness of the inner wall of the barrel 2 (barrel 11) excluding the dewatering barrel 11b.

[0099] Furthermore, in the plurality of plate-shaped members 13 constituting the dewatering machine barrel 11b, preferably at least one of the two surfaces (two surfaces located on opposite sides of each other) of each plate-shaped member 13 is roughened (roughened surface treatment), more preferably both surfaces are roughened (roughened surface treatment). As a result, since at least one of the two surfaces forming the gap 17, preferably both, becomes roughened, the static pressure of the gap 17 is increased, moisture is selectively discharged from the gap 17, and the leakage of resin components to the outside through the gap 17 can be suppressed or prevented.

[0100] Furthermore, in this embodiment, the gap 17 between the plurality of plate-shaped members 13 arranged along the X direction serves as a flow path for water separated from the resin material. Therefore, by adjusting the shape and size of the plate-shaped members 13, the length of the flow path through the gap 17 can be easily adjusted. For example, in Figure 6 In this case, the distance L1 from the periphery of the plate-shaped member 13 to the opening 12 becomes the flow path length for water to pass through the gap 17. Therefore, by adjusting the distance L1, the discharge efficiency of water separated from the resin material as it is discharged to the outside through the gap 17 can be controlled. For example, if the distance L1 is too large, the discharge efficiency of water through the gap 17 may decrease, but by reducing the distance L1 to a certain extent, for example, setting it to less than 20 mm, it becomes easy to ensure the discharge efficiency of water through the gap 17.

[0101] Furthermore, since each of the multiple plate-shaped members 13 is relatively thin, their individual mechanical strength is not very high. However, by arranging the multiple plate-shaped members 13 along the X direction, the overall mechanical strength of the multiple plate-shaped members 13 can be improved.

[0102] again, Figures 6-9 In this case, each of the multiple plate-like members 13 has a protrusion 13a that partially protrudes along the long axis (X direction) of the barrel. This protrusion 13a can also be considered as a portion thicker than the area outside the protrusion 13a in the plate-like member 13. Figures 6-9 The diagram illustrates a case where the opening 14 through which the fixing member 15 penetrates is formed in the protrusion 13a. In the plate-like member 13, the thickness of the peripheral region of the opening 14 is greater than the thickness of other regions. The protrusion 13a can be formed integrally with the plate-like member 13, or it can be formed by bonding other members, such as thin film members like metal foil, to the plate-like member 13 with uniform thickness.

[0103] The gap 17 between the multiple plate-shaped members 13 can be defined according to the protrusion 13a. That is, the size (dimension in the X direction) of the gap 17 between the multiple plate-shaped members 13 can be defined according to the protrusion amount H1 of the protrusion 13a. When the protrusion amount H1 of the protrusion 13a is small, the size in the X direction of the gap 17 becomes smaller; when the protrusion amount H1 of the protrusion 13a is large, the size in the X direction of the gap 17 becomes larger. The larger the size in the X direction of the gap 17, the greater the efficiency of water discharge through the gap 17. When the size in the X direction of the gap 17 becomes larger, there is a possibility that resin components will leak to the outside through the gap 17. Therefore, the size in the X direction of the gap 17 is preferably set to an appropriate size according to the characteristics of the raw material 7 supplied to the barrel 2.

[0104] In this embodiment, since the gap 17 between the plurality of plate-shaped members 13 can be defined according to the protrusion 13a, the protrusion amount H1 of the protrusion 13a can be set according to the type and characteristics of the resin material supplied to the barrel 2, and the dimension of the gap 17 in the X direction can be adjusted to the optimal dimension. This balances improving the discharge efficiency of water separated from the resin material when discharged to the outside through the gap 17 with preventing the resin components contained in the resin material from leaking to the outside through the gap 17. The protrusion amount H1 of the protrusion 13a can be, for example, about 0.01 to 1 mm.

[0105] Furthermore, even if the internal pressure of the barrel 2 changes, the dimension of the gap 17 in the X direction between the plurality of plate-shaped members 13 remains almost unchanged. Therefore, only the moisture separated from the resin material can be reliably discharged through the gap 17 between the plurality of plate-shaped members 13.

[0106] Furthermore, even without the protrusion 13a, the protrusion amount H1 of the protrusion 13a can be set to zero. Even without the protrusion 13a, by coarsening the surface roughness of the opposing surfaces of the plurality of plate-shaped members 13, numerous tiny irregularities exist on the surface of the plate-shaped members 13, ensuring a flow path for moisture between the opposing surfaces of the plurality of plate-shaped members 13. Therefore, even without the protrusion 13a, moisture separated from the resin material can be discharged to the outside through the gap 17.

[0107] Figure 12 as well as Figure 13 A plan view showing a modified example of the dewatering machine barrel 11b ( Figure 12 ) and sectional views ( Figure 13 ). Figure 12 Showing the equivalent of a bottom view, Figure 13 Showing the equivalent of the above Figure 5 The cross-section, Figure 12 The cross-sectional view at the location of line A1-A1 shown almost corresponds to Figure 13 .

[0108] exist Figure 12 as well as Figure 13 In this case, multiple plate-shaped members 13 arranged along the X direction are covered by a metal cover member (metal member, metal block) 21. By covering the multiple plate-shaped members 13 arranged along the X direction with the metal cover member 21, the plate-shaped members 13 can be protected. The cover member 21 covers the periphery of the multiple plate-shaped members 13 arranged along the X direction, but has an opening 22 for water drainage. Thus, water draining from the gaps 17 between the multiple plate-shaped members 13 can be drained to the outside through the opening 22 of the cover member 21.

[0109] The invention described above is based on its specific implementation method, but the invention is not limited to this implementation method, and various modifications can be made without departing from the spirit of the invention.

Claims

1. An extrusion apparatus, characterized in that, Includes the following: barrel; A resin material containing moisture is supplied to the supply section inside the barrel; The screw is built into the barrel and transports the supplied resin material to the barrel; as well as A dehydration barrel body positioned in the middle of the barrel for discharging water separated from the resin material. in, The dehydration drum has a structure consisting of multiple plate-shaped members arranged along the long axis of the drum, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

2. The extrusion apparatus according to claim 1, characterized in that, The moisture separated from the resin material is selectively discharged between the opposing surfaces of the plurality of plate-shaped members.

3. The extrusion apparatus according to claim 1, characterized in that, When the surface roughness of the opposing surfaces of the plurality of plate-shaped members is expressed as the arithmetic mean roughness Ra, Ra is 1.6a to 25a.

4. The extrusion apparatus according to claim 1, characterized in that, Each of the plurality of plate-shaped members has a protrusion that partially protrudes along the long axis of the barrel. The gap between the plurality of plate-shaped members is defined by the protrusion.

5. A dewatering barrel for use in an extrusion apparatus, the extrusion apparatus comprising a barrel, a screw housed within the barrel, and a dewatering barrel for discharging water separated from resin material supplied to the barrel. The dehydration barrel has a structure consisting of a plurality of plate-shaped members arranged along the long axis of the barrel, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

6. The dewatering barrel according to claim 5, characterized in that, When the surface roughness of the opposing surfaces of the plurality of plate-shaped members is expressed as the arithmetic mean roughness Ra, Ra is 1.6a to 25a.

7. A dehydration method, characterized in that, It includes the following processes: (a) The process of feeding a resin material containing moisture into the barrel; (b) The process of conveying the resin material by the screw inside the barrel after the aforementioned (a) process; (c) The process of discharging the water separated from the resin material from the dehydration barrel body located in the middle of the barrel after the aforementioned (a) process; (d) The process of extruding the resin material from a die connected to the front end of the barrel after the aforementioned (b) and (c) steps; in, The dehydration drum has a structure consisting of multiple plate-shaped members arranged along the long axis of the drum, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

8. The dehydration method according to claim 7, characterized in that, In the aforementioned step (c), the moisture separated from the resin material is selectively discharged between the opposing surfaces of the plurality of plate-shaped members.

9. The dehydration method according to claim 7, characterized in that, When the surface roughness of the opposing surfaces of the plurality of plate-shaped members is expressed as the arithmetic mean roughness Ra, Ra is 1.6a to 25a.

10. The dehydration method according to claim 7, characterized in that, Each of the plurality of plate-shaped members has a protrusion that partially protrudes along the long axis of the barrel. The gap between the plurality of plate-shaped members is defined by the protrusion.

11. A method for manufacturing resin particles, characterized in that, It includes the following processes: (a) The process of feeding a resin material containing moisture into the barrel; (b) The process of conveying the resin material by the screw inside the barrel after the aforementioned (a) process; (c) The process of discharging the water separated from the resin material from the dehydration barrel body located in the middle of the barrel after the aforementioned (a) process; (d) The process of extruding the resin material from a die connected to the front end of the barrel after the aforementioned (b) and (c) steps; (e) The process of cutting the resin material extruded from the mold to form resin particles after the aforementioned (d) process; in, The dehydration drum has a structure consisting of multiple plate-shaped members arranged along the long axis of the drum, each having an opening through which the screw passes. The surface roughness of the opposing surfaces of the plurality of plate-shaped members is greater than the surface roughness of the inner wall of the barrel.

12. The method for manufacturing resin particles according to claim 11, characterized in that, In the aforementioned step (c), the moisture separated from the resin material is selectively discharged between the opposing surfaces of the plurality of plate-shaped members.

13. The method for manufacturing resin particles according to claim 11, characterized in that, When the surface roughness of the opposing surfaces of the plurality of plate-shaped members is expressed as the arithmetic mean roughness Ra, Ra is 1.6a to 25a.

14. The method for manufacturing resin particles according to claim 11, characterized in that, Each of the plurality of plate-shaped members has a protrusion that partially protrudes along the long axis of the barrel. The gap between the plurality of plate-shaped members is defined by the protrusion.

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