JP2009196233A - Tubular polymer filter and polymer film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tubular polymer filter which is free from the inclusion of a foreign substance, i.e. a resident deleterious product of a polymer, into a finished product film, and a polymer film. <P>SOLUTION: This tubular polymer filter is equipped with a support member having a polymer inflow aperture, a cap member joined with the upstream side, in the polymer flow direction, of the support member and a filter element joined with the support member and/or the cap member. In addition, the cap member is joined with the support member so that the average flow velocity of the polymer in whatever region of the polymer outflow side of the filter element, is higher than 0 m/minute. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cylindrical polymer filter and a polymer film.

  Conventionally, films manufactured using polyester, polypropylene, polyamide, polycarbonate, polyolefin, and acrylic resin are generally manufactured by a process as shown in FIG.

  FIG. 7 is a schematic diagram illustrating an example of a film manufacturing apparatus.

  In FIG. 7, the film manufacturing apparatus 30 is provided with an extruder 1, a gear pump 2, a filter 3, a base 4, a cooling roll 5, a stretching device 6, and a winder 7 in order from the upstream side in the polymer flow direction. A thickness meter 8 is installed between the stretching device 6 and the winder 7, and a thickness controller 9 is electrically connected to the thickness meter 8 and the base 4.

  In the above apparatus, the raw material polymer is supplied to the extruder 1, melted, and then extruded to the gear pump 2. The gear pump 2 has a function of making the discharge amount (delivery amount) constant. The molten resin discharged by a constant amount is removed from the foreign matter and the like through the filter 3 and then supplied to the base 4. The base 4 is provided with a slit having a predetermined gap, and the molten resin is extruded from the slit into a sheet shape, cooled and solidified on the rotating cooling roll 5, and then a solidified sheet 10 is obtained. The solidified sheet 10 is subsequently stretched by the stretching device 6 and wound up as a film by the winder 7. At that time, the thickness of the film in the width direction (direction perpendicular to the paper surface) is measured by the thickness meter 8, and the slit gap of the base 4 is adjusted by the thickness controller 9 based on the obtained thickness data. A product film having an inner thickness (small variation in thickness) is obtained.

  The filter 3 used in the above apparatus includes a leaf disk type, a cylindrical filter, a screen type, and the like, and is appropriately used according to the quality of the film to be manufactured and the manufacturing conditions. The cylindrical filter includes a simple cylindrical type and a pleated type with an increased filtration area. Hereinafter, this cylindrical filter will be described with reference to FIGS.

  FIG. 3 is a schematic longitudinal sectional view showing a conventional cylindrical filter.

  In FIG. 3, a cylindrical filter 40 includes a filter element 11 having a filtration function, a support member 12 that supports the filter element 11 and guides the polymer downstream from a plurality of polymer inlets, and an upstream in the polymer flow direction. It consists of a cap member 13 for sealing and a flange member 14 that allows the downstream end portions to be attached to a casing or the like, and has a structure in which the members are joined by welding. FIG. 4 is a schematic longitudinal sectional view showing a state in which the cylindrical filter 40 shown in FIG. 3 is housed in the casing 50 with the cap member facing the upstream side, and the black arrows indicate the flow of the molten polymer. The molten polymer flows from the upstream side, fills the space between the cylindrical filter 40 and the casing 50, passes through the filter element, passes through the polymer inlet provided in the column member, and the center of the column member. It flows out from the downstream. The cylindrical filter 40 may be used in units of one unit, or may be used by connecting a plurality of units in series or in parallel.

  Next, the vicinity of the connecting portion between the cap member 13 and the column member 12 will be described in detail with reference to FIG. 5A is a schematic longitudinal sectional view of the cylindrical filter shown in FIG. 3, and FIG. 5B is a schematic sectional view showing the vicinity of the cap member. In (b), the cap member 13 is provided with a fitting allowance 15 for fitting inside the cylindrical column member 12, and after the cap member 13 and the column member 12 are fitted together, a boundary surface 16 between the two is provided. Are welded at the locations indicated by the welds 20. This is to prevent the cap member 13 and the column member 12 from shifting during welding, and is a technique that is usually performed in a cylindrical filter (Patent Document 1).

However, adopting such a fitting structure causes another problem depending on the type of polymer. That is, in FIG. 5 (b), the polymer may enter and stay in the slight gap 17 of the fitting between the cap member 13 and the support member 12, and if the polymer stays, depending on the type and composition, it may be altered, thermally deteriorated, Deterioration with time occurred, and the deteriorated polymer often flowed out in the downstream direction due to the influence of fluctuation in filtration pressure, etc., and often occurred as a foreign matter defect on the sheet 10. Further, when the welded portion 21 between the element 11 and the cap member 13 is far from the polymer inlet 18 provided in the column member 12, the gap 19 between the element and the cap member is generated in the same manner, and the polymer stays and deteriorates. Often spilled into the water, which was a problem.
JP 11-319431 A

  An object of the present invention is to provide a cylindrical polymer filter and a polymer film in which foreign substances, that is, polymer deteriorating deterioration products are not mixed into a product.

To achieve the above object, the present invention has the following features.
(1) A strut member having a polymer inlet, a cap member joined to the upstream side of the strut member in the polymer flow direction, and a filter element joined to the strut member and / or the cap member. A cylindrical polymer filter, wherein the cap member is joined to the support member so that the average flow rate of the polymer is greater than 0 m / min in any region on the polymer outlet side of the filter element. .
(2) When the most upstream polymer inlet is the most upstream polymer inlet in the polymer flow direction of the strut member, the center of the most upstream polymer inlet is joined to the cap member and the strut member. The cylindrical polymer filter according to (1) above, wherein a distance from the portion is shorter than a radius of the most upstream polymer inlet.

  (3) When the polymer inlet provided on the most upstream side in the polymer flow direction of the support member is the uppermost polymer inlet, the center of the uppermost polymer inlet is joined to the filter element and the cap member. The cylindrical polymer filter according to the above (1) or (2), wherein the distance to the part is not more than [radius of the most upstream polymer inlet + 10 mm] or less.

  (4) The cylindrical polymer filter according to any one of (1) to (3), wherein the cap member has a polymer inlet.

  (5) A polymer film produced using a polymer that has passed through the cylindrical polymer filter according to any one of (1) to (4).

In the present invention, the “upstream” in the “polymer flow direction” of the cylindrical polymer filter means the side where the polymer is first contacted at both ends of the cylindrical polymer filter, and usually the cap member is joined. Indicates side.
Further, “the average flow velocity of the polymer is greater than 0 m / min” means that all the places where there is room for the polymer to enter (the gap between the cap member and the column member (FIG. 5) on the downstream side in the polymer flow direction of the filter element. (Including the gap 17) in (b)), when an arbitrary flow path is assumed, the average flow speed obtained by averaging the flow speed from the central flow speed of the flow path to the wall surface is greater than 0 m / min. In other words, it means that the polymer always flows at any point.

  According to the present invention, a cylindrical polymer that can eliminate even a slight gap generated by using a support member, a cap member, and an element member, and does not contain foreign matter (deteriorated polymer residue) into the product. Filters and polymer films can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Of course, the present invention is not limited to these.

  FIG. 1 is a schematic longitudinal sectional view showing a cylindrical polymer filter according to an embodiment of the present invention, wherein (a) is an overall schematic sectional view of the filter, and (b) is an enlarged detail view near the cap member. In FIG. 1, a cylindrical polymer filter 60 includes a cylindrical column member 12 provided with a plurality of polymer inlets, a filter element 11 disposed around the column member 12 and a cap joined to one end of the column member. The flange 14 is joined to the end opposite to the side on which the cap member 13 is joined for joining with other members. Further, the vicinity of the cap member is as shown in FIG. 1B, and the cap member 13 is joined to the support member 12 having the polymer inlet 18 by welding at the welding portion 20. Further, the filter element 11 is joined to the cap member 13 at the welded portion 21 by welding.

  Now, in the present invention, as shown in FIG. 1B, by devising the shape of the cap member 13, the average flow velocity of the polymer is less than 0 m / min in any region on the polymer outflow side of the filter element. It is configured to be large. That is, since the cap member 13 has a shape such that there is no allowance for fitting to the support member as seen in the conventional member, the gap 17 ′ can be made sufficiently wide, and a so-called polymer retention portion is formed. It can be lost. In this way, by making the cross-sectional area of the region where the cap member enters the inside of the column member (hereinafter referred to as the intrusion region) smaller than the cross-sectional area inside the column member, the flow of the polymer becomes smooth, and conventionally the retention portion The average flow velocity of the portion that has become can be made larger than 0 m / min. When the cross-sectional shape of the intrusion region is a circle, it is important that the radius is sufficiently smaller than the inner diameter of the support member, and the difference is preferably 1 mm or more, more preferably 3 mm or more. The above difference is more preferably realized at least in the vicinity of the boundary surface 16, and more preferably realized in the entire intrusion region.

  Moreover, it is preferable that the longitudinal cross-sectional shape in the penetration | invasion area | region of a cap member is made into circular arc shape as shown in FIG.1 (b), and, thereby, the flow of a polymer becomes smoother. Thus, when the longitudinal cross-sectional shape of the cap member is an arc shape on the inner side (inner side of the column member) 16 of the boundary surface (joint part) 16 between the column member and the cap member, the radius of curvature thereof is that of the molten polymer. Although it may be determined as appropriate depending on the type or the like, for example, it is preferable that the range is within the range of the radius of the polymer inlet 18 to the inner diameter of the column member 12.

  Next, the position of the polymer inlet provided in the support member will be described with reference to FIG. FIG. 2 is a schematic perspective view showing the vicinity of the end where the cap member of the support member is joined. In FIG. 2A, the distance L is defined by the center of the most upstream polymer inlet 18 ′ provided on the most upstream side in the polymer flow direction of the strut member, and the boundary surface between the cap member (not shown) and the strut member ( The distance to the joint) 16 is shown. The distance L is preferably as short as possible, and more preferably the distance L is shorter than the radius of the most upstream polymer inlet. FIG. 2B shows a case where the distance L coincides with the radius of the most upstream polymer inlet, and the strut member used in FIG. 1 also has the shape as in this example. FIG. 3C shows a case where the distance L is shorter than the radius of the most upstream polymer inlet, and the inlet has a shape in which a support member is cut out.

  In the present invention, in particular, the shape shown in FIGS. 2B and 2C can more effectively prevent the polymer flowing in from the upstream direction of the filter from staying in a slight gap. It is possible to maintain an average flow rate of the polymer higher than 0 m / min in any region downstream of the filter element (the polymer outflow side), that is, to keep the polymer always flowing. You can do it effectively.

  In the present invention, for example, as shown in FIG. 1B, the position of the welded portion (joined portion) 21 between the filter element 11 and the cap member 13 is preferably as close as possible to the most upstream polymer inlet 18. . However, since the welded portion (joint portion) 20 between the cap member 13 and the column member 12 interferes, the distance between the center of the most upstream polymer inflow port and the joint portion of the filter element and the cap member is set to [the most upstream polymer. The radius of the inlet + 10 mm] or less is preferable, and this distance is more preferably [the radius of the most upstream polymer inlet + 5 mm] or less. By taking such a form, the gap generated between the element 11 and the cap member 13 can be minimized, so that the polymer retention portion can be eliminated.

  Next, a cylindrical filter according to another embodiment of the present invention will be described with reference to FIG.

  In FIG. 6A, the cylindrical polymer filter 70 is provided with the column member 12 and the filter element 11 as described in FIG. 1, and the flange 14 is joined to the downstream end in the polymer flow direction. . Further, in FIG. 6B, a plate-like cap member 80 provided with a polymer inlet 18 ″ is joined to the column member 12 at the welded portion 20 on the upstream side in the polymer flow direction of the cylindrical polymer filter. Further, the upstream portion thereof is covered with a filter element 11 ′. The filter elements 11 and 11 ′ are welded at the joint 21.

  Thus, by devising the cap member and not providing the intrusion region, the polymer staying portion is eliminated, and the average flow rate of the polymer on the polymer outflow side of the filter element is made larger than 0 m / min in any region. It becomes possible.

  In FIG. 6, the cap member 80 has been described as having a flat plate shape. However, of course, other shapes that do not cause a stay portion, such as a shape that is convex upward or a shape in which the central portion is raised, are used. If it is the shape which does not provide, it will become a preferable aspect. Specifically, for example, a shape as shown in FIG. 8 is also preferable.

  In the present invention, it is verified by the method described below that the average polymer flow velocity downstream of the filter element is greater than 0 m / min.

  As shown in FIG. 9, a filter and casing cut in half in the polymer flow direction are prepared, and a glass or transparent plastic plate is attached to the cut surface. With this configuration, a pseudo polymer fluid is flowed from the upstream side, and the flow state of each part is confirmed. In order to measure the flow velocity, particles such as carbon black are mixed with a pseudo polymer, the movement behavior of the particles is photographed with a video, and the average flow velocity is calculated from the movement distance and movement time. As the pseudo polymer, NOF's unilube or edible chickenpox can be used.

  The length of the cylindrical filter of the present invention is preferably about 300 to 1,200 mm, and the diameter (diameter) is preferably about φ50 mm to φ100 mm. It is preferable that the polymer inlets are arranged uniformly and over a wide range on the support member, and a forward arrangement, a staggered arrangement, and the like are also preferable forms. The size of the inlet is preferably a diameter (diameter) of about 5 to 10 mm. Of course, the dimensions are not limited to the above range.

  Various materials can be used for the cylindrical filter of the present invention. Any material can be used for the filter element 11 as long as the material has a so-called filtration function, such as a stainless steel metal fiber, a sintered porous body, and a mesh. Further, the filtration accuracy of the filter may be appropriately applied depending on the quality requirements of the product. For example, a filter material such as an ultra-high precision 1-3 μm cut may be used, or a filter medium such as a 10-20 μm cut may be used. Alternatively, a filter medium having a cut of 30 μm or more may be used.

  Generally, the support member 12 and the cap member 13 can be made of stainless steel such as SUS304, SUS316, SUS630, or SUS420, but carbon steel may also be used.

  In the above description, the metal-based material is mainly described. However, depending on the type of polymer, the filter can be formed of a resin-based material or a ceramic-based material.

  The configuration of the filter element may be a cylindrical type in which the element is wound around a support member, or a pleat type that is bent into a pleat shape in order to increase the filtration area. The same effect can be obtained by using one filter or a plurality of filters.

  The polymer applicable in the present invention is not particularly limited, such as polyester, polypropylene, polyamide, polycarbonate, polyolefin, acrylic resin, and may be a thermoplastic resin or a thermosetting resin.

  In addition, polymer films manufactured using the polymer that has passed through the cylindrical polymer filter of the present invention described above are used for packaging such as packages and laminates, magnetic recording media such as digital video cameras, optical uses such as displays, flexible It can be used in various industries and applications such as semiconductor applications such as substrates. The polymer film to be produced may have a single layer configuration in the thickness direction or may have a multilayer configuration of two or more layers.

[Example 1]
Using a cylindrical polymer filter having the configuration shown in FIG. 1, a polymer film was manufactured using a film manufacturing apparatus as shown in FIG. The polymer is polyester, the extrusion temperature is 280 ° C., the discharge rate is 500 kg / hr, the filter element is a metal fiber with a filtration accuracy of 15 μm wound in a cylindrical shape on the column member, and the polymer inlet of the filter column member is 10 mm in diameter, The distance between the center of the most upstream polymer inlet and the joint between the cap member and the strut member is 5 mm, and the distance between the center of the most upstream polymer inlet and the joint between the filter element and the cap member is 15 mm. A thing was used. Separately prepared filters of the same specifications and observed the flow state of the polymer downstream of the filter element using a longitudinal cross section model as shown in Fig. 9, and it was confirmed that there was no stagnation and that the polymer was flowing in each channel. did it. Using this filter, a film was produced for one week using a T die with a die set to a slit gap of 1.4 mm. As a result, no foreign material defect due to the deteriorated polymer occurred during sheet production, and a film of good quality was obtained.

  In order to confirm the presence / absence of the staying portion and clarify the effect of the present invention, the filter was cooled and decomposed with the polymer attached after the film was manufactured, and the vicinity of the cap member was cut to confirm the discoloration of the polymer. As a result, the location where the polymer stayed and discolored was not found, and the effect of the present invention could be confirmed.

[Example 2]
Using a cylindrical polymer filter having the configuration shown in FIG. 1, a polymer film was manufactured using a film manufacturing apparatus as shown in FIG. However, as a support | pillar member, the thing as shown in FIG.2 (c) was used. The polymer is polyolefin, the extrusion temperature is 260 ° C., the discharge rate is 200 kg / hr, the filter element is a cylindrical sintered body of porous sintered metal with a filtration accuracy of 20 μm, and the polymer inlet of the filter column member has a diameter. 10 mm, the distance between the center of the most upstream polymer inlet and the joint between the cap member and the support member is 3 mm, and the distance between the center of the most upstream polymer inlet and the joint between the filter element and the cap member is 10 mm. A 10 mm one was used. Separately prepared filters of the same specifications and observed the flow state of the polymer downstream of the filter element using a longitudinal cross section model as shown in Fig. 9, and it was confirmed that there was no stagnation and that the polymer was flowing in each channel. did it. Using this filter, a film was produced for 2 weeks using a coat hanger die with a die set to a slit gap of 1.2 mm. As a result, no foreign material defect due to the deteriorated polymer was produced during sheet production, and a good quality sheet was obtained.

  In order to confirm the presence / absence of the staying portion and clarify the effect of the present invention, the filter was cooled and decomposed with the polymer attached after the film was manufactured, and the vicinity of the cap member was cut to confirm the discoloration of the polymer. As a result, the location where the polymer stayed and discolored was not found, and the effect of the present invention could be confirmed.

[Example 3]
Using a cylindrical polymer filter having the configuration shown in FIG. 6, a polymer film was produced using a film production apparatus as shown in FIG. The polymer is polypropylene, the extrusion temperature is 250 ° C., the discharge rate is 100 kg / hr, the filter element is a metal fiber with a filtration accuracy of 20 μm wound around a column member, and the polymer inlet of the filter column member is 10 mm in diameter. The distance between the center of the most upstream polymer inlet and the joint between the cap member and the support member is 0 mm, and the distance between the center of the most upstream polymer inlet and the joint between the filter element and the cap member is 12 mm. The thing of was used. Separately prepared filters of the same specifications and observed the flow state of the polymer downstream of the filter element using a longitudinal cross section model as shown in Fig. 9, and it was confirmed that there was no stagnation and that the polymer was flowing in each channel. did it. Using this filter, a film was produced for 2 weeks using a T-die with a die set to a slit gap of 2.1 mm. As a result, no foreign material defect due to the deteriorated polymer occurred during film production, and a good quality sheet was obtained.

  In order to confirm the presence or absence of the staying portion and clarify the effect of the present invention, the filter was cooled and decomposed with the polymer adhered after the film was manufactured, and the vicinity of the upper element was cut to confirm the discoloration of the polymer. As a result, the location where the polymer stayed and discolored was not found, and the effect of the present invention could be confirmed.

[Comparative Example 1]
A cylindrical polymer filter having the configuration shown in FIG. 5 was used, and a polymer film was manufactured using a film manufacturing apparatus as shown in FIG. The polymer is an acrylic resin, the extrusion temperature is 260 ° C., the discharge rate is 120 kg / hr, the filter element is a metal fiber with a filtration accuracy of 20 μm wound in a pleat shape around the column member, and the polymer inlet of the filter column member is The distance between the center of the most upstream polymer inlet and the junction of the cap member and the support member is 10 mm, and the distance between the center of the upstream polymer inlet and the junction of the filter element and the cap member. 30 mm was used. A filter with the same specifications was prepared separately, and when the flow state of the polymer downstream of the filter element was observed using a longitudinal section model as shown in FIG. 9, it was found between the cap member and the column member and between the filter element and the cap member. A staying part was confirmed. Using this filter, a film was produced for one week using a T-die with a die set to a slit gap of 1.3 mm. As a result, a foreign material defect caused by a deteriorated polymer occurred during sheet manufacture at a fixed position in the width direction of the sheet, and a sheet with good quality could not be obtained.

  Similarly, in order to confirm the presence or absence of the staying portion, the filter was cooled and decomposed with the polymer attached after the sheet was manufactured, and the vicinity of the cap member was cut to confirm the discoloration of the polymer. As a result, a spot where the polymer stays in the slight gap between the fitting portions of the cap member and the support member and discolors was found.

It is a schematic longitudinal cross-sectional view of the cylindrical polymer filter which concerns on one embodiment of this invention. It is a schematic perspective view which shows the example of the support | pillar member used in this invention. It is a schematic longitudinal cross-sectional view which shows the conventional cylindrical polymer filter. It is a schematic longitudinal cross-sectional view which shows a polymer flow in the case of using the cylindrical polymer filter of FIG. It is a schematic longitudinal cross-sectional view which shows the cap member vicinity of the cylindrical polymer filter of FIG. It is a schematic longitudinal cross-sectional view of the cylindrical polymer filter which concerns on other one Embodiment of this invention. It is the schematic of a general film manufacturing apparatus. It is a schematic longitudinal cross-sectional view of the cylindrical polymer filter which concerns on one embodiment of this invention. It is a cross-sectional model schematic diagram of a cylindrical polymer filter for verifying the effect of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Extruder 2 Gear pump 3 Filter 4 Cap 5 Cooling roll 6 Stretching device 7 Winder 8 Thickness meter 9 Thickness controller 10 Solidified sheet 11 Filter element 11 'Filter element 11''Filter element 12 Strut member 12' Strut member 12 '' Strut Member 13 Cap member 14 Flange 15 Cap member fitting allowance 16 Boundary surface between cap member and support member 17 Clearance between cap member and support member 17 'Clearance between cap member and support member 18 Polymer Inlet 18 'Uppermost polymer inlet 18 "Polymer inlet 18'" Polymer inlet 19 Gap between element and cap member 20 Welded portion between cap member and strut member 21 Welded portion between cap member and element 30 Film Manufacturing equipment 40 Tubular polymer filter 50 casing 60 cylindrical polymer filter 70 the tubular polymer filter 80 the cap member 85 the cap member 90 cylindrical polymer filter 100 tubular polymer filter section model 101 Visualization Glass

Claims (5)

Cylindrical polymer comprising: a strut member having a polymer inlet, a cap member joined to the upstream side of the strut member in the polymer flow direction, and a filter element joined to the strut member and / or the cap member A cylindrical polymer filter, wherein the cap member is joined to the support member so that the average flow rate of the polymer is greater than 0 m / min in any region on the polymer outflow side of the filter element. When the polymer inlet provided on the most upstream side in the polymer flow direction of the strut member is the most upstream polymer inlet, the center of the most upstream polymer inlet and the joint between the cap member and the strut member The cylindrical polymer filter according to claim 1, wherein a distance is shorter than a radius of the most upstream polymer inlet. When the polymer inlet provided on the most upstream side in the polymer flow direction of the support member is the uppermost polymer inlet, the center of the uppermost polymer inlet and the joint between the filter element and the cap member The cylindrical polymer filter according to claim 1 or 2, wherein the distance is equal to or less than [radius of the most upstream polymer inlet + 10 mm]. The cylindrical polymer filter according to claim 1, wherein the cap member has a polymer inlet. The polymer film manufactured using the polymer which passed the cylindrical polymer filter in any one of Claims 1-4.

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