JP2009297945A - Flat die and method for manufacturing sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat die where a sheet end part can be made to be a molten resin is different from a central portion employed as a product. <P>SOLUTION: The flat die is equipped with: a plug 1 comprising a main layer injection port 20 where the molten resin to be the main layer is injected, a sub layer injection port where the molten resin to be the sub layer is injected, and a sub layer outflow port for flowing out the molten resin to be the sub layer; and a manifold part 30 which can insert the plug 1 into its own side surface, and flows out the molten resin injected from the main layer injection port 20 and the molten resin flown out from the sub layer outflow port to the outside. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a die that is an apparatus for extruding a molten resin, and more particularly to a flat die that is a die for producing a sheet.

  Conventionally, a T die (flat die) used mainly for producing a film / sheet product is an apparatus for extruding a molten resin sent from a melt plasticizer such as an extruder in a thin and wide state. For the T-die, a molding method is used in which a single resin or a different resin is laminated in the thickness direction of the sheet is extruded.

  The resin extruded from the T-die in the form of a sheet has a neck-in phenomenon in which the width direction shrinks until it contacts the cooling device, and an edge bead phenomenon in which the sheet end becomes thicker. Is done. In particular, in the case of optical sheets and the like where the raw materials are expensive and the physical properties of the product are strictly controlled, there is a problem that the cut sheet ends cannot be recycled and must be discarded, resulting in a large cost loss.

  In order to solve this problem, it is preferable to use an apparatus configuration in which an inexpensive resin is flowed in advance to a portion where the end portion is thick (sublayer) and the original resin is flowed (main layer) only to a central portion adopted as a product. Assuming a structure in which different resins are laminated in the width direction, the die inflow portion is provided at the upper end of the main layer and the sub layer, and there are both flow paths in the die body and the layers are joined in the width direction by the manifold portion. There is known a T-die that employs an extrusion method for providing a distribution (for example, Patent Document 1).

Japanese Patent No. 3449960

  However, it is difficult to arbitrarily change the width of the sub-layer in the method disclosed in Patent Document 1 described above. In addition, the method disclosed in Patent Document 1 described above requires the same resin as the main layer to flow in the flow path of the sub layer even when it is desired not to use the sub layer, that is, to form only the main layer, depending on the application. In addition, there are structural problems such as the fact that the main body dimension of the upstream part from the manifold part of the die must be long.

  The present invention has been made to solve the above-described problems, and provides a flat die and a sheet manufacturing method capable of laminating different fluids at a central portion adopted as a product and its end portions. With the goal.

  In order to solve the above-described problem, the present invention is a flat die, and a first fluid injection part into which a first fluid that is a predetermined fluid is injected, and a second fluid that is a fluid different from the first fluid. A plug having a second fluid injection part into which the second fluid is injected and a second fluid outflow part from which the second fluid flows out, and the plug can be inserted into a side surface of the plug, and the second fluid injection part is injected from the first fluid injection part. 1 fluid and the manifold part which flows out the 2nd fluid which flows out out of the said 2nd fluid outflow part outside.

  Further, the present invention is characterized in that in the flat die described above, the manifold portion adjusts an outflow amount of the second fluid based on an insertion length of the plug with respect to the manifold portion.

  In order to solve the above-described problem, the present invention is a sheet manufacturing method for manufacturing a sheet, injecting a first fluid that is a predetermined fluid into a flat die, and a manifold portion of the flat die, A second fluid, which is a fluid different from the first fluid, is injected into the flat die from the side surface of the manifold portion that flows out to the outside, and the injected first fluid and second fluid are injected into the manifold. A sheet is produced by extruding from a part.

  In the sheet manufacturing method according to the present invention, the second fluid may include a second fluid injecting portion into which the second fluid is injected and a second fluid outflow portion through which the second fluid flows out. A plug provided is inserted into a side surface of the manifold portion and injected through the plug.

  Furthermore, the present invention is characterized in that, in the sheet manufacturing method described above, the outflow amount of the second fluid is adjusted based on an insertion length of the plug with respect to the manifold portion.

  According to the present invention, since the second fluid is injected from the side surface of the manifold portion that is an opening through which the product is extruded, different fluids can be stacked at the central portion and the end portion.

  Embodiments of the present invention will be described below. In the flat die in the present embodiment, a resin boundary layer is provided in the width direction, and a sheet is manufactured by pouring a different resin only at the end of the flat die. In order to realize this technique, the present embodiment uses a flat die having a side feed function in which a plug having a resin flow path is inserted on the side of the flat die and a different resin is poured from the plug.

  FIG. 1 shows a flat die in the present embodiment. The flat die 10 includes a main layer inlet 20 (first fluid injection portion) into which a molten resin (first fluid) serving as a main layer is injected. Further, the flat die 10 has a manifold section 30 for flowing out a molten resin injected into the lower portion thereof from the main layer inlet 20 and a molten resin (second fluid) serving as a sub-layer flowing out of the plug 1 described later. Is provided.

  The manifold portion 30 includes a seal 3 that prevents leakage of molten resin to the outside, a seal presser 2 that supports the seal 3, and a sub-plate 4 that supports the plug 1 so that the plug 1 described later can be inserted. A plug insertion mechanism. The plug 1 inserted into the manifold portion 30 can slide in the sheet width direction.

  Although only one end of the flat die 10 is shown in FIG. 1, it is assumed that the flat die 10 has the same configuration as described above at both ends.

  Next, an external view of the plug 1 in this embodiment is shown in FIG. 2A, and a cross-sectional view of the plug 1 is shown in FIG.

  The plug 1 includes a sub-layer inlet 5 (second fluid inlet) into which molten resin serving as a sub-layer is injected and a sub-layer outlet 6 (second fluid outlet) through which the injected molten resin flows out. As shown in FIGS. 2A and 2B, the shape of the sub-layer outlet 6 is thin and wide so that it is flat in the width direction, and therefore injected from the sub-layer inlet 5. The made molten resin flows out from the sub-layer outlet 6 in a flat shape.

  Further, in the present embodiment, the joint surfaces of the plug 1 and the manifold portion 30 are inclined so as to be paired with each other so that the sub-layer outlet 6 always faces the outflow direction of the manifold portion 30 when inserted. However, the embodiment is not limited.

  Next, FIG. 3 shows a state in which the plug 1 is inserted into the manifold portion 30 of the flat die 10 and the molten resin of the main layer and the sub layer is injected and extruded. FIG. 3A shows a state where the plug stroke (insertion length) of the plug 1 is 110 mm, and FIG. 3B shows an example where the plug stroke is 140 mm, which is the longest plug stroke. . In FIG. 3, the molten resin serving as the main layer is indicated by a black arrow with a white background and the flow direction thereof, and the molten resin serving as a sub layer is indicated by a white arrow with the black background and a flow direction thereof.

  3B is larger than the state shown in FIG. 3A, the amount of flow out of the manifold portion 30 is increased due to the longer insertion length, and the length of the molten resin in the sub-layer in the sheet width direction is also increased. Become more.

  Furthermore, FIG. 4 shows an enlarged view of the insertion location of the plug 1 shown in FIG. As shown in FIGS. 3 and 4, by adjusting the plug stroke of the plug 1, the flow rate of the molten resin flowing out of the sub-layer and the length in the sheet width direction are also adjusted. 4 (a) corresponds to FIG. 3 (a), and FIG. 4 (b) corresponds to FIG. 3 (b).

  In this way, the main layer can be introduced from the top of the flat die as usual, and the sub layer can be introduced from the plug provided with the flow path from the side of the flat die, so that different resins can be laminated in the sheet width direction. Further, by adopting the plug system as in the present embodiment, it becomes possible to easily change the width of the sub-layer by adjusting the plug stroke, and when a plug without a flow path is used, the sheet of only the main layer is used. Can be molded.

  According to the present embodiment, the following effects can be obtained.

  As in the present embodiment, the shape of the flat die body can be made the same as the conventional one by allowing the sub-layer to flow from the side surface end portion by the flow path type plug.

  Further, the width of the sub-layer can be freely adjusted by adjusting the stroke of the plug provided with the flow path.

  Furthermore, by using a plug that does not have a flow path, it is possible to easily change to a sheet forming method using only the main layer.

It is the block diagram of the flat die concerning embodiment of this invention, and the enlarged view of a plug insertion location vicinity. It is the external view and sectional drawing of the plug concerning embodiment of this invention. It is a figure which shows the state by which molten resin is inject | poured into the flat die concerning embodiment of this invention. It is an enlarged view of the plug insertion location vicinity in the state by which molten resin is inject | poured into the flat die concerning embodiment of this invention.

Explanation of symbols

  1 plug, 2 seal holder, 3 seal, 4 subplate, 10 flat die, 5 sublayer inlet, 6 sublayer outlet, 20 main layer inlet, 30 manifold part.

Claims (5)

A first fluid injection part into which a first fluid that is a predetermined fluid is injected;
A plug comprising a second fluid injection part into which a second fluid, which is a fluid different from the first fluid, is injected, and a second fluid outflow part through which the second fluid flows out;
A manifold part that allows the plug to be inserted into a side surface of the self part, and flows out the first fluid injected from the first fluid injection part and the second fluid that flows out from the second fluid outflow part;
A flat die comprising The flat die according to claim 1,
The flat die according to claim 1, wherein the manifold portion adjusts an outflow amount of the second fluid based on an insertion length of the plug with respect to the manifold portion. A sheet manufacturing method for manufacturing a sheet,
Injecting a first fluid, which is a predetermined fluid, into the flat die,
Injecting a second fluid, which is a fluid different from the first fluid, from the side surface of the manifold portion that flows out of the fluid to the outside into the flat die,
A sheet manufacturing method, wherein a sheet is manufactured by extruding the injected first fluid and the second fluid from the manifold portion. In the sheet manufacturing method according to claim 3,
The second fluid includes a plug including a second fluid injection portion into which the second fluid is injected and a second fluid outflow portion through which the second fluid flows out, and is inserted into a side surface of the manifold portion. The sheet manufacturing method is characterized by being injected through the sheet. In the sheet manufacturing method according to claim 4,
The outflow amount of the second fluid is adjusted based on an insertion length of the plug with respect to the manifold portion.

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