WO2012117513A1

WO2012117513A1 - Multilayer extrusion molding device

Info

Publication number: WO2012117513A1
Application number: PCT/JP2011/054576
Authority: WO
Inventors: 和治中嶋; 隆夫西村; 剛志齋藤; 知生下林
Original assignee: 株式会社サン・エヌ・ティ
Priority date: 2011-03-01
Filing date: 2011-03-01
Publication date: 2012-09-07

Abstract

Provided is a feed block type multilayer extrusion molding device capable of stably and reliably producing a multilayer film in which the thickness of each layer is even in the width direction even when said multilayer extrusion molding device is used for co-extrusion in which the difference of the flow properties of resins is large or the difference of the thickness of layers is large. A feed block (2A) is provided with a flat main flow path (21) linearly connected to the extrusion flow path (10) of a single layer T-die (1) and flat sub flow paths (22) which have the same width and merge with the main flow path (21) at an angle. Main flow path choke bars (3) expand and contract the flow path cross-sectional area of the main flow path (21) in the thickness direction by means of the advancing/retracting movement from the sub flow path (22) side to the main flow path (21) and sub flow path choke bars (4) expand and contract the flow path cross-sectional area of the sub flow paths (22) in the thickness direction by means of the advancing/retracting movement relative to the sub flow paths (22). The main flow path choke bars (3) and the sub flow path choke bars (4) are disposed on the merging part (20) of the main flow path (21) and the sub flow paths (22). Moreover, the feed block (2A) has choke operation means (5) for individually advancing and retracting choke division pieces (31, 41) configured by dividing the main flow path choke bars (3) and the sub flow path choke bars (4) into three or more parts in the width direction and in the same division pattern.

Description

複層押出成形装置Multi-layer extrusion equipment

　本発明は、複層フィルムを共押出によって製造する複層押出成形装置、特に複数の溶融樹脂流を該フィードブロックで合流させ、その合流溶融樹脂を単層Ｔダイから押し出して複層フィルムを製出するフィードブロック方式の複層押出成形装置に関する。 The present invention relates to a multilayer extrusion molding apparatus for producing a multilayer film by coextrusion, in particular, a plurality of molten resin streams are merged by the feed block, and the merged molten resin is extruded from a single-layer T die to produce a multilayer film. The present invention relates to a feed block type multilayer extrusion molding apparatus.

　この種の複層押出成形装置では、例えば図５（ａ）（ｂ）に示すように、単層Ｔダイ１の上流側に連結用プレート２４を介してフィードブロック２が連結されており、各々溶融押出機（図示省略）から供給される複数（図では３つ）の溶融樹脂流Ｐ１～Ｐ３を各々導入口２ａよりフィードブロック２内に導入し、該フィードブロック２内で各々偏平な流路２５を通して合流させ、その合流溶融樹脂Ｐ１０を単層Ｔダイ１の押出流路（マニホールド）１０へ送り込み、該単層Ｔダイ１で幅方向に展開して押出口１１から所要幅の複層フィルムＦとして押し出す。なお、図示を省略しているが、フィードブロック２の流路２５や単層Ｔダイ１の押出流路１０に厚さ調整用のチョークバーを設けることも多い。しかして、このような複層押出成形装置においては、単層Ｔダイ１とフィードブロック２の組合せを変えることにより、複層フィルムＦの樹脂種、層数、フィルム幅、各層の厚み比率等の変更に対応できるという利点がある。 In this type of multilayer extrusion molding apparatus, for example, as shown in FIGS. 5 (a) and 5 (b), the feed block 2 is connected to the upstream side of the single-layer T die 1 via a connection plate 24. A plurality (three in the figure) of molten resin streams P1 to P3 supplied from a melt extruder (not shown) are introduced into the feed block 2 from the introduction ports 2a, respectively, and the flat flow paths in the feed block 2 are provided. 25, and the combined molten resin P10 is fed into the extrusion flow path (manifold) 10 of the single-layer T die 1 and developed in the width direction by the single-layer T die 1 to be a multilayer film having a required width from the extrusion port 11. Extrude as F. In addition, although illustration is abbreviate | omitted, the choke bar for thickness adjustment is often provided in the flow path 25 of the feed block 2 or the extrusion flow path 10 of the single-layer T die 1. Thus, in such a multilayer extrusion molding apparatus, by changing the combination of the single layer T die 1 and the feed block 2, the resin type of the multilayer film F, the number of layers, the film width, the thickness ratio of each layer, etc. There is an advantage that it can cope with the change.

　ところで、共押出による複層押出成形では、溶融樹脂流がＴダイによって幅方向に展開する行程で、幅方向の位置によって移動距離、流路抵抗、流速分布、温度分布、圧力分布等に違いを生じて層厚に影響するため、製出する複層フィルムＦの各層の厚みを均一にすることが普遍的な課題である。この点、マルチマニホールド方式の複層押出成形装置では、Ｔダイ自体に設けた複数のマニホールドを各々通過した溶融樹脂をチョークバーによって厚み調整した上で合流させるのが一般的であるが、合流から押出口までの距離が短く、且つ合流部から押出口への幅方向の展開が比較的に小さいため、その移動過程での幅方向の変動因子による層厚への影響が少なくなる。そして、幅方向の厚みの均一化についても、一般的に各流路に介在するチョークバーを撓ませて幅方向の間隙調整を行うことで対応できる。また、マルチマニホールド方式において、合流前の流路壁に形成した薄肉部をボルトを介して幅方向複数箇所で押し引きして変位させ、もって幅方向の厚み調整を行う方法も知られている（特許文献１，２）。 By the way, in the multi-layer extrusion molding by coextrusion, in the process in which the molten resin flow is developed in the width direction by the T-die, the travel distance, flow path resistance, flow velocity distribution, temperature distribution, pressure distribution, etc. differ depending on the position in the width direction. Since it occurs and affects the layer thickness, it is a universal problem to make the thickness of each layer of the multilayer film F to be produced uniform. In this regard, in a multi-manifold type multilayer extrusion molding apparatus, the molten resin that has passed through a plurality of manifolds provided in the T-die itself is generally merged after adjusting the thickness with a choke bar. Since the distance to the extrusion port is short and the development in the width direction from the joining portion to the extrusion port is relatively small, the influence on the layer thickness due to the variation factor in the width direction in the moving process is reduced. Further, the uniform thickness in the width direction can be dealt with by generally adjusting the gap in the width direction by bending a choke bar interposed in each flow path. Also, in the multi-manifold system, a method of adjusting the thickness in the width direction by pushing and pulling the thin wall portion formed on the flow path wall before joining at a plurality of positions in the width direction via bolts is also known ( Patent Documents 1 and 2).

　しかるに、フィードブロック方式では、図示のようにフィードブロック２の合流部２０から単層Ｔダイ１の押出口１１までの距離が長い上、フィードブロック２の流路出口２ｂから押出口１１へ幅方向に通常１０倍前後と大きく展開するため、合流部２０の手前でチョークバーを介して各流路の厚み調整を行っても、押出口までの移動過程で種々の変動因子による影響を受けて層厚が変わり易く、特に各層の幅方向の厚みを均一にすることが非常に難しくなる。しかも、フィードブロック２の各流路２５の幅が狭く、それだけ介在させるチョークバーも短くなるため、これを撓ませて幅方向の間隙調整を行うことは困難である。また、前記マルチマニホールド方式における流路壁の薄肉部を変位させる構成をフィードブロック方式に適用しても、やはり流路幅が狭いため、薄肉部の変位度合及び変位パターンが制約され、幅方向の間隙を大きく複雑に調整できない上、押し引きするボルトに負荷がかかって折損し易くなるという問題もある。 However, in the feed block system, as shown in the figure, the distance from the merging portion 20 of the feed block 2 to the extrusion port 11 of the single-layer T die 1 is long, and the width direction from the flow path outlet 2b of the feed block 2 to the extrusion port 11 Therefore, even if the thickness of each flow path is adjusted through the choke bar before the junction 20, the layer is affected by various factors in the process of moving to the extrusion port. The thickness is easily changed, and in particular, it is very difficult to make the thickness of each layer in the width direction uniform. Moreover, since the width of each flow path 25 of the feed block 2 is narrow and the choke bar interposed therebetween is also shortened, it is difficult to adjust the gap in the width direction by bending it. Moreover, even if the configuration of displacing the thin wall portion of the flow path wall in the multi-manifold method is applied to the feed block method, the flow width is still narrow, so the displacement degree and displacement pattern of the thin wall portion are restricted, and the width direction There is a problem that the gap cannot be adjusted to be large and complicated, and the bolt to be pushed and pulled is easily loaded and broken.

　そこで、フィードブロック方式について、フィードブロックの合流域の各流路に幅方向に重なる複数のチョークバーを設け、各チョークバーを独立に移動調整することにより、流路断面形状を単層Ｔダイから押し出される複層フィルムの幅方向の厚み分布が均一になるように調整する手段が提案されている（特許文献３）。 Therefore, for the feed block system, a plurality of choke bars overlapping in the width direction are provided in each flow path in the merging area of the feed block, and each choke bar is independently moved and adjusted, so that the cross-sectional shape of the flow path can be changed from the single layer T die. Means for adjusting the thickness distribution in the width direction of the extruded multilayer film to be uniform has been proposed (Patent Document 3).

特開平１０－２１７３１０号公報JP-A-10-217310 特開平１０－２３５７１０号公報Japanese Patent Laid-Open No. 10-235710 特許第２８１８３５４号公報Japanese Patent No. 2818354

　しかしながら、前記従来の提案手段は、流動特性が近似した樹脂同士をほぼ同じ厚みで共押出しする際には有用であるが、樹脂同士の流動特性の差や層同士の厚み差が大きい共押出しに適用した場合に、各層の幅方向の厚みが均一な複層フィルムを製出することは極めて困難であった。とりわけ、近年においては資源リサイクルの観点より、再生ペレットを原料とする主層の片面又は両面をバージン樹脂の表層で覆った形態のリサイクルフィルムの需要が増大しているが、その製造に前記提案手段を用いた場合、フィードブロック内の合流域における各流路の断面形状を前記複数のチョークバーで調整しても、単層Ｔダイから押し出される各層の幅方向の厚みの均一化に繋がらず、満足な品質のフィルムは得られなかった。 However, the conventional proposed means is useful when co-extrusion of resins having similar flow characteristics with approximately the same thickness, but co-extrusion with a large difference in flow characteristics between resins and a large difference in thickness between layers. When applied, it was extremely difficult to produce a multilayer film having a uniform thickness in the width direction of each layer. In particular, in recent years, from the viewpoint of resource recycling, there is an increasing demand for a recycled film in which one or both sides of a main layer made of recycled pellets are covered with a virgin resin surface layer. If the cross-sectional shape of each flow path in the merging area in the feed block is adjusted with the plurality of choke bars, it does not lead to uniform thickness in the width direction of each layer extruded from the single-layer T die, A satisfactory quality film could not be obtained.

　本発明者らは、上述の事情に鑑みて、フィードブロック方式の複層押出成形において、樹脂同士の流動特性の差や層同士の厚み差が大きい共押出しに適用した場合でも、各層の幅方向の厚みが均一な複層フィルムを製出し得る手段を究明すべく、実験研究を重ねる過程で、まず既述の従来手段による問題を生じる要因について様々な角度から検討した。その結果、例えば前記の再生ペレットを原料とする主層を有する複層フィルムの場合、その主層の再生樹脂と表層のバージン樹脂とで溶融状態での流動特性が大きく異なる上、該主層と表層とで厚みの差が大きいことから、フィードブロック内の各流路の断面形状を前記複数のチョークバーによって様々に調整しても、合流部では樹脂流が相互に干渉し合い、特に流量の少ない表層側の樹脂流が乱されることにより、調整した流路断面形状が単層Ｔダイから押し出される各層の幅方向の厚みにうまく反映せず、幅方向の厚み分布を設定するための充分な指標が得られないことが判明した。 In view of the above-mentioned circumstances, the present inventors, in the feed block type multi-layer extrusion molding, even when applied to co-extrusion having a large difference in flow characteristics between resins and a large difference in thickness between layers, the width direction of each layer In order to find out the means for producing a multilayer film with a uniform thickness, in the process of repeating experimental research, first, the factors causing the problems caused by the conventional means described above were examined from various angles. As a result, for example, in the case of a multilayer film having a main layer made of the above-mentioned recycled pellets, the flow characteristics in the molten state differ greatly between the main layer recycled resin and the surface layer virgin resin, Since the difference in thickness between the surface layer and the surface layer is large, even if the cross-sectional shape of each flow path in the feed block is variously adjusted by the plurality of choke bars, the resin flows interfere with each other at the junction, Due to the disturbance of the small resin flow on the surface layer side, the adjusted channel cross-sectional shape does not reflect well on the thickness in the width direction of each layer extruded from the single-layer T die, and is sufficient for setting the thickness distribution in the width direction It was found that no good index could be obtained.

　そして、上記知見に基づいて更なる実験研究を重ねた結果、フィードブロック内で特定方向に設定した主流路と複流路との合流部に、主流路及び複流路に幅方向に分割したチョークバーを特定配置で介在させることにより、該合流部における樹脂流の相互干渉を抑えて流れの乱れを防止でき、もって各流路で調整した流路断面形状を単層Ｔダイから押し出される各層の幅方向の厚みに確実に反映させることが可能となり、これによって樹脂同士の流動特性の差や層同士の厚み差が大きい共押出しに適用した場合でも、幅方向の各層の厚みが均一な高品位の複層フィルムを安定的に製出できることを見出し、本発明をなすに至った。 As a result of further experimental research based on the above findings, a choke bar divided in the width direction into the main flow path and the multi-flow path is formed at the junction of the main flow path and the multi-flow path set in a specific direction in the feed block. By interposing in a specific arrangement, it is possible to prevent the disturbance of the flow by suppressing the mutual interference of the resin flow in the junction, and thus the cross-sectional shape of the flow path adjusted in each flow path is the width direction of each layer extruded from the single-layer T die. Therefore, even when applied to coextrusion where the difference in flow characteristics between resins and the difference in thickness between layers are large, the thickness of each layer in the width direction is uniform and high quality. The present inventors have found that a layer film can be stably produced and have made the present invention.

　本発明の課題解決手段を図面の参照符号を付して示せば、請求項１の発明は、単層Ｔダイ１の上流側にフィードブロック２Ａ（２Ｂ）が連結され、複数の溶融樹脂流Ｐ１，Ｐ２（Ｐ３）をフィードブロック２Ａ（２Ｂ）で合流させ、その合流溶融樹脂Ｐ１０を単層Ｔダイ１から押し出して複層フィルムＦを製出する複層押出成形装置において、フィードブロック２Ａ（２Ｂ）は、単層Ｔダイ１の押出流路１０に直線的に連通する偏平な主流路２１と、該主流路２１に対して同幅で斜めに合流する偏平な副流路２２とを備え、該フィードブロック２Ａ（２Ｂ）の主流路２１と副流路２２との合流部２０に、主流路２１に対して副流路２２側から出退動作して当該主流路１の流路断面積を厚み方向に拡縮する主流路チョークバー３と、副流路２２に対して出退動作して当該副流路２の流路断面積を厚み方向に拡縮する副流路チョークバー４とが設けられ、主流路チョークバー３と副流路チョークバー４とが共に同一の分割パターンで幅方向に３以上に分割構成され、その各チョーク分割片３１，４１を個別に出退動作させるチョーク操作手段５を有することを特徴としている。 If the problem-solving means of the present invention is shown with reference numerals in the drawings, the invention of claim 1 is that the feed block 2A (2B) is connected to the upstream side of the single-layer T-die 1 and a plurality of molten resin streams P1. , P2 (P3) are joined by the feed block 2A (2B), and the joined molten resin P10 is extruded from the single-layer T die 1 to produce a multilayer film F. In the multilayer extrusion molding apparatus, the feed block 2A (2B ) Includes a flat main flow channel 21 that communicates linearly with the extrusion flow channel 10 of the single-layer T-die 1 and a flat sub flow channel 22 that joins the main flow channel 21 with the same width and obliquely. The flow path cross-sectional area of the main flow path 1 is obtained by moving the main flow path 21 from the side of the sub flow path 22 to the junction 20 between the main flow path 21 and the sub flow path 22 of the feed block 2A (2B). Main channel choke bar 3 expanding and contracting in the thickness direction, and sub channel 2 And a sub-channel choke bar 4 that expands and contracts the channel cross-sectional area of the sub-channel 2 in the thickness direction, and the main channel choke bar 3 and the sub-channel choke bar 4 are both The choke operation means 5 is configured to be divided into three or more in the width direction with the same division pattern, and to individually move the

choke division pieces

31 and 41 out and out.

　請求項２の発明は、上記請求項１の複層押出成形装置において、主流路チョークバー３が副流路２２に沿って出退動作するように主流路２１に対して傾斜配置すると共に、この主流路チョークバー３の外側側面３ｂが該副流路２２の幅方向に沿う片側流路壁を構成してなる。 According to a second aspect of the present invention, in the multilayer extrusion molding apparatus according to the first aspect, the main flow path choke bar 3 is inclined with respect to the main flow path 21 so that the main flow path choke bar 3 moves out and retreats along the sub flow path 22. The outer side surface 3 b of the main channel choke bar 3 forms a one-side channel wall along the width direction of the sub-channel 22.

　請求項３の発明は、上記請求項１の複層押出成形装置において、主流路２１に対して複数本の副流路２２が合流し、各副流路２の合流部２０毎に主流路チョークバー３及び副流路チョークバー４が配置してなる構成としている。 According to a third aspect of the present invention, in the multi-layer extrusion molding apparatus according to the first aspect, a plurality of sub flow paths 22 merge with the main flow path 21, and the main flow path choke is provided for each merging portion 20 of each sub flow path 2. The bar 3 and the sub-flow channel choke bar 4 are arranged.

　請求項４の発明は、上記請求項３の複層押出成形装置において、主流路２１に対して少なくとも一対の副流路２２，２２が該主流路２１の厚み方向両側から同位置で合流し、その厚み方向両側の合流部２０，２０に各々対応して主流路チョークバー３及び副流路チョークバー４が配置してなる構成としている。 According to a fourth aspect of the present invention, in the multilayer extrusion molding apparatus according to the third aspect, at least a pair of

sub-channels

22 and 22 join the main channel 21 at the same position from both sides in the thickness direction, The main flow path choke bar 3 and the sub flow path choke bar 4 are arranged so as to correspond to the merging portions 20 on both sides in the thickness direction.

　請求項５の発明は、上記請求項１の複層押出成形装置において、フィードブロック２Ａ（２Ｂ）の合流部２０における主流路２１の最小流路断面積が副流路２２の最大流路断面積よりも大きく設定されてなるものとしている。 The invention according to claim 5 is the multilayer extrusion molding apparatus according to claim 1, wherein the minimum channel cross-sectional area of the main channel 21 in the merge portion 20 of the feed block 2 </ b> A (2 </ b> B) is the maximum channel cross-sectional area of the sub-channel 22. It is assumed that it is set larger than.

　請求項６の発明は、上記請求項１～５の何れかの複層押出成形装置において、チョーク操作手段５は、各チョーク分割片３１，４１に内端を固着して外端側がフィードブロック２Ａ（２Ｂ）の外側へ突出したねじ軸５１と、該ねじ軸５１の外端側の雄ねじ部５１ａに螺合し、フィードブロック２Ａ（２Ｂ）に回転可能で且つ軸方向移動不能に保持された雌ねじ筒５２とで構成され、該雌ねじ筒５２の捻回操作でねじ軸５１を軸方向移動するように構成されてなる。 According to a sixth aspect of the present invention, in the multi-layer extrusion molding apparatus according to any one of the first to fifth aspects, the choke operating means 5 has an inner end fixed to each of the choke divided

pieces

31 and 41, and the outer end side is the feed block 2A. (2B) a screw shaft 51 protruding outward, and a female screw threadably engaged with a male screw portion 51a on the outer end side of the screw shaft 51, and rotatably held in the feed block 2A (2B) but not axially movable. The screw shaft 51 is configured to move in the axial direction by a twisting operation of the female screw tube 52.

　次に、本発明の効果について、図面の参照符号を付して説明する。まず、請求項１の発明に係る複層押出成形装置では、フィードブロック２Ａ（２Ｂ）内の主流路２１と副流路２２との合流部２０に、該主流路１及び副流路２を各々厚み方向に拡縮する主流路チョークバー３及び副流路チョークバー４が設けられているが、両チョークバー３，４が同一の分割パターンで幅方向に３以上に分割構成され、その各チョーク分割片３１，４１が個別に出退動作できるから、主流路１側及び副流路２側からそれぞれ合流する溶融樹脂流Ｐ１，Ｐ２（Ｐ３）の厚みを、各チョーク分割片３１，４１に対応する幅方向の区間毎に増減調整できる。しかして、主流路チョークバー３は主流路２１に対して副流路２２側から出退動作する構成であり、前記幅方向の区間単位で、副流路チョークバー４によって調整される副流路２２側の溶融樹脂流Ｐ２（Ｐ３）の増減に対応して、主流路２１側の溶融樹脂流Ｐ１を副流路２２側から狭めることができるから、その狭めることで空いた合流部２０の空間領域に副流路２２側からの溶融樹脂流Ｐ２（Ｐ３）がそのままスムーズに入り込めて、主流路２１側からの溶融樹脂流Ｐ１を押し退ける形にはならない。しかも、主流路２１が単層Ｔダイ１の押出流路１０に直線的に連通しており、主流路２１側からの溶融樹脂流Ｐ１は合流部２０で狭められても変化せずに一貫して単層Ｔダイ１の押出流路１０へ向かう直線的な流れを維持するから、この溶融樹脂流Ｐ１に対して副流路２２側からの溶融樹脂流Ｐ２（Ｐ３）が順流として干渉し合うことなく合流し、以降の合流溶融樹脂Ｐ１０は合流部２０での融樹脂流Ｐ１，Ｐ２（Ｐ３）の乱れのない積層状態を保ったまま単層Ｔダイ１の押出流路１０へ移動してゆく。 Next, effects of the present invention will be described with reference numerals in the drawings. First, in the multilayer extrusion molding apparatus according to the first aspect of the present invention, the main flow path 1 and the sub flow path 2 are respectively provided at the junction 20 of the main flow path 21 and the sub flow path 22 in the feed block 2A (2B). A main flow path choke bar 3 and a sub flow path choke bar 4 that expand and contract in the thickness direction are provided. Both

choke bars

3 and 4 are divided into three or more in the width direction by the same division pattern, and each choke division is divided. Since the

pieces

31 and 41 can individually move in and out, the thicknesses of the molten resin flows P1 and P2 (P3) that merge from the main flow path 1 side and the sub flow path 2 side correspond to the choke divided

pieces

31 and 41, respectively. Increase or decrease can be adjusted for each section in the width direction. Thus, the main flow path choke bar 3 is configured to move out of the main flow path 21 from the side of the sub flow path 22 and is adjusted by the sub flow path choke bar 4 in the section in the width direction. Corresponding to the increase / decrease of the molten resin flow P2 (P3) on the 22 side, the molten resin flow P1 on the main flow channel 21 side can be narrowed from the sub flow channel 22 side. The molten resin flow P2 (P3) from the auxiliary flow path 22 side can smoothly enter the region as it is, and the molten resin flow P1 from the main flow path 21 side is not pushed away. Moreover, the main flow path 21 communicates linearly with the extrusion flow path 10 of the single-layer T die 1, and the molten resin flow P1 from the main flow path 21 side does not change even if it is narrowed at the merge portion 20, and is consistent. Since the straight flow toward the extrusion flow path 10 of the single layer T die 1 is maintained, the molten resin flow P2 (P3) from the sub flow path 22 side interferes with the molten resin flow P1 as a forward flow. The joined molten resin P10 is moved to the extrusion flow path 10 of the single-layer T die 1 while maintaining the undisturbed laminated state of the molten resin flows P1, P2 (P3) at the joining portion 20. go.

　従って、この複層押出成形装置によれば、合流部２０において主流路２１及び副流路２２を幅方向の区間単位で調整した流路断面形状が押し出された積層フィルムＦの各層の幅方向の厚みに確実に反映するから、該流路断面形状と複層フィルムＦの各層の幅方向の厚みプロフィールとの相関より、得られる複層フィルムＦの各層の幅方向の厚みが均一になる流路断面形状を容易に且つ確実に見出すことができる。もって、この複層押出成形装置は、樹脂同士の流動特性の差や層同士の厚み差が大きい共押出しに適用した場合でも、幅方向の各層の厚みが均一な高品位の複層フィルムを安定的に製造できる。 Therefore, according to this multilayer extrusion molding apparatus, the width direction of each layer of the laminated film F in which the flow path cross-sectional shape in which the main flow path 21 and the sub flow path 22 are adjusted in the unit of the width direction is extruded in the merging portion 20. Since the thickness is surely reflected in the thickness, the thickness in the width direction of each layer of the obtained multilayer film F is uniform from the correlation between the cross-sectional shape of the channel and the thickness profile in the width direction of each layer of the multilayer film F. The cross-sectional shape can be easily and reliably found. Therefore, even when this multi-layer extrusion molding apparatus is applied to co-extrusion with a large difference in flow characteristics between resins and a large difference in thickness between layers, a high-quality multi-layer film with a uniform thickness in each layer in the width direction can be stabilized. Can be manufactured.

　請求項２の発明によれば、主流路チョークバー３が主流路２１に対して傾斜配置し、その外側側面３ｂが副流路２２の幅方向に沿う片側流路壁を構成するから、常に主流路チョークバー３の先端前方が合流点となり、該チョークバー３にて主流路２１が断面調整された位置に副流路２２側からの溶融樹脂流Ｐ２（Ｐ３）がそのまま合流するから、合流部２０における流れの相互干渉がより効果的に抑えられると共に、主流路チョークバー３による主流路２１の溶融樹脂流Ｐ１への抵抗が傾斜配置によって小さくなる。また、一般的にフィードブロック２Ａ（２Ｂ）は複数の金型部材を組み合わせて構成するが、副流路２２に臨んで金型分離面を設定することにより、簡素で且つ機能的な部材構成に容易に設定できる。 According to the second aspect of the invention, the main flow path choke bar 3 is inclined with respect to the main flow path 21, and the outer side surface 3 b forms a one-side flow path wall along the width direction of the sub flow path 22. Since the front end of the road choke bar 3 is a confluence, the molten resin flow P2 (P3) from the sub-flow path 22 side joins the choke bar 3 at a position where the cross section of the main flow path 21 is adjusted. 20 is more effectively suppressed, and the resistance of the main channel choke bar 3 to the molten resin flow P1 in the main channel 21 is reduced by the inclined arrangement. In general, the feed block 2A (2B) is configured by combining a plurality of mold members. By setting the mold separation surface facing the sub-flow channel 22, a simple and functional member configuration is obtained. Easy to set.

　請求項３の発明によれば、主流路２１に対して複数本の副流路２２が合流し、各副流路２の合流部２０毎に主流路チョークバー３及び副流路チョークバー４が配置するから、３層以上の複層フィルムＦとして、各層の幅方向の厚みが均一なものを確実に且つ安定的に製造できる。 According to the invention of claim 3, a plurality of sub flow paths 22 merge with the main flow path 21, and the main flow path choke bar 3 and the sub flow path choke bar 4 are provided for each merging portion 20 of each sub flow path 2. Since it arrange | positions, the thing with uniform thickness of the width direction of each layer can be manufactured reliably and stably as the multilayer film F of 3 or more layers.

　請求項４の発明によれば、主流路２１の同位置に厚み方向両側から副流路２２，２２が合流し、その両側の合流部２０，２０に各々対応して主流路チョークバー３及び副流路チョークバー４が配置するから、主流路２１を同位置で両側から主流路チョークバー３によって絞る形で空いた両側の空間領域に、両側の副流路２２，２２から溶融樹脂流Ｐ２，Ｐ３を同時に乱れなくスムーズに合流させ、もって３層以上の各層の厚みが均一な高品位の複層フィルムＦを確実に得ることができると共に、３層以上の複層押出に適用するフィードブロック２Ａを機能的でコンパクトに構成できる。 According to the invention of claim 4, the sub-channels 22, 22 join from the both sides in the thickness direction at the same position of the main channel 21, and the main channel choke bar 3 and the sub-channel choke bar 3 correspond to the merging

portions

20, 20 on both sides. Since the flow path choke bar 4 is arranged, the molten resin flow P2, from the

auxiliary flow paths

22 and 22 on both sides is formed in the space areas on both sides, which are squeezed by the main flow path choke bar 3 from both sides at the same position. A feed block 2A that can smoothly and smoothly join P3 at the same time, and can reliably obtain a high-quality multilayer film F in which the thickness of each layer of three or more layers is uniform, and is applied to the extrusion of three or more layers. Can be configured functionally and compactly.

　請求項５の発明によれば、フィードブロック２Ａ（２Ｂ）の合流部２０における主流路２１の最小流路断面積が副流路２２の最大流路断面積よりも大きいため、副流路２２側からの溶融樹脂流Ｐ２は主流路２１側からの溶融樹脂流Ｐ１よりも流量が少なくなって本来は乱され易いが、上記の両流路２１，２２と両チョークバー３，４の配置構成によって乱れが確実に抑えられ、もって主層に対して薄い副層が積層した複層フィルムとして高品位のものを安定的に製造できる。 According to the invention of claim 5, since the minimum channel cross-sectional area of the main channel 21 in the merging portion 20 of the feed block 2A (2B) is larger than the maximum channel cross-sectional area of the sub-channel 22, the sub-channel 22 side The molten resin flow P2 from the main flow passage 21 has a smaller flow rate than the molten resin flow P1 from the main flow passage 21 side and is likely to be disturbed originally, but depending on the arrangement configuration of the

flow passages

21 and 22 and the choke bars 3 and 4 described above. Disturbance is reliably suppressed, and thus a high-quality film can be stably produced as a multilayer film in which a thin sublayer is laminated with respect to the main layer.

　請求項６の発明によれば、チョーク操作手段５の構成が簡素で且つ機能的であるから、主流路チョークバー３及び副流路チョークバー４の各チョーク分割片３１，４１の出退調整を容易に確実に行えると共に、フィードブロック２Ａ（２Ｂ）が構造簡単になる。 According to the sixth aspect of the present invention, the choke operating means 5 has a simple and functional configuration, so that the choke divided

pieces

31 and 41 of the main flow path choke bar 3 and the sub flow path choke bar 4 can be adjusted. The feed block 2A (2B) can be easily and reliably structured, and the structure is simplified.

本発明の第一実施形態に係る複層押出成形装置のフィードブロックを示し、（ａ）は背面図、（ｂ）は側面図、（ｃ）は連結用プレートを取り外した状態での正面図である。The feed block of the multilayer extrusion molding apparatus which concerns on 1st embodiment of this invention is shown, (a) is a rear view, (b) is a side view, (c) is a front view in the state which removed the connection plate. is there. 同フィードブロックの縦断側面図である。It is a vertical side view of the same feed block. 図２のＸ－Ｘ線における上半部の断面矢視図である。FIG. 3 is a cross-sectional arrow view of the upper half portion along line XX in FIG. 2. 本発明の第二実施形態に係る複層押出成形装置のフィードブロックの縦断側面図である。It is a vertical side view of the feed block of the multilayer extrusion molding apparatus concerning a second embodiment of the present invention. フィードブロック方式の複層押出成形装置を概略的に示し、（ａ）は横断平面図、（ｂ）は（ａ）のＹ－Ｙ線の縦断側面図である。1 schematically shows a feed block type multilayer extrusion molding apparatus, in which (a) is a cross-sectional plan view, and (b) is a longitudinal sectional side view of line YY in (a).

　以下に、本発明に係る複層押出成形装置の実施形態について、図面を参照して具体的に説明する。なお、この複層押出成形装置は、既述した図５で示す一般的なフィードブロック方式の複層押出成形装置と同様に単層Ｔダイの上流側にフィードブロックが連結された基本構造を有するから、図５での図示と共通する構成要素については同一符号を附してその説明を省略する。 Hereinafter, an embodiment of a multilayer extrusion molding apparatus according to the present invention will be specifically described with reference to the drawings. This multi-layer extrusion molding apparatus has a basic structure in which a feed block is connected to the upstream side of a single-layer T-die, like the general feed block type multi-layer extrusion molding apparatus shown in FIG. Therefore, the same components as those shown in FIG.

　第一実施形態の複層押出成形装置は、例えば再生ペレットを原料とする主層の両面をバージン樹脂からなる薄い表層で被覆したリサイクルフィルムのような３層構造の複層フィルムの製造に適用するために、図１～図３で示す構成のフィードブロック２Ａを備えるものである。 The multilayer extrusion molding apparatus of the first embodiment is applied to the production of a multilayer film having a three-layer structure such as a recycled film in which both surfaces of a main layer made of recycled pellets are covered with a thin surface layer made of virgin resin. For this purpose, the feed block 2A having the configuration shown in FIGS. 1 to 3 is provided.

　このフィードブロック２Ａは、単層Ｔダイ１の押出流路１０に直線的に連通する中央の主流路２１と、該主流路２１に対して厚み方向両側から同位置で斜めに合流する一対の副流路２２，２２とを備えており、図示省略した溶融押出機から供給される溶融樹脂流Ｐ１～Ｐ３をそれぞれ、外面に設けた円形の導入口２ａより前段展開部２ｃを経て偏平な各流路２１，２２，２２へ導入するようになっている。また、主流路２１と両副流路２２，２２は同幅の偏平な形状であるが、主流路２１は各副流路２２よりも厚み方向に広く流路断面積が大きく設定されている。 The feed block 2A includes a central main channel 21 that linearly communicates with the extrusion channel 10 of the single-layer T die 1, and a pair of sub-channels that merge obliquely at the same position from both sides in the thickness direction with respect to the main channel 21. The molten resin flows P1 to P3 supplied from a melt extruder (not shown) are respectively flown from the circular introduction port 2a provided on the outer surface through the upstream development portion 2c. It introduces to the

paths

21, 22, and 22. The main flow path 21 and the

sub flow paths

22 and 22 have a flat shape with the same width, but the main flow path 21 is wider than the sub flow paths 22 in the thickness direction and has a larger flow cross-sectional area.

　そして、フィードブロック２Ａには、主流路２１と両副流路２２，２２との両側の合流部２０，２０にそれぞれ、主流路２１に対して副流路２２側から出退動作して当該主流路１の流路断面積を厚み方向に拡縮する主流路チョークバー３と、副流路２２に対して出退動作して当該副流路２の流路断面積を厚み方向に拡縮する副流路チョークバー４とが設けられている。その主流路チョークバー３は、出退方向に長い形状で副流路２２に沿うように主流路２１に対して傾斜配置しており、主流路２１に臨む先端面３ａが流路方向と平行になると共に、外側側面３ｂが副流路２２の幅方向に沿う片側流路壁２２ａを構成している。一方、副流路チョークバー４は、短い形状で主流路２１に対して垂直な出退方向に配置しており、副流路２２に臨む先端面４ａが流路方向と平行になっている。また、合流部２０における主流路２１の最小流路断面積は副流路２２の最大流路断面積よりも大きくなっている。 In the feed block 2A, the merging

portions

20 and 20 on both sides of the main flow path 21 and both the

sub flow paths

22 and 22 are respectively moved out of the main flow path 21 from the sub flow path 22 side. A main channel choke bar 3 that expands and contracts the channel cross-sectional area of the channel 1 in the thickness direction, and a secondary flow that expands and contracts the channel cross-sectional area of the sub channel 2 in the thickness direction by moving back and forth with respect to the sub channel 22 A road choke bar 4 is provided. The main flow path choke bar 3 is inclined with respect to the main flow path 21 so as to extend along the sub flow path 22 in a shape that is long in the withdrawing / retracting direction, and the front end surface 3a facing the main flow path 21 is parallel to the flow path direction. At the same time, the outer side surface 3b constitutes a one-side channel wall 22a along the width direction of the sub-channel 22. On the other hand, the sub-flow channel choke bar 4 has a short shape and is disposed in the exit / retreat direction perpendicular to the main flow channel 21, and the tip surface 4 a facing the sub-flow channel 22 is parallel to the flow channel direction. In addition, the minimum channel cross-sectional area of the main channel 21 in the junction 20 is larger than the maximum channel cross-sectional area of the sub-channel 22.

　ここで、主流路チョークバー３及び副流路チョークバー４は、図３に示すように、互いに同一の分割パターンで流路幅方向に５つに等分割されており、その各チョーク分割片３１，４１がチョーク操作手段５によって個別に出退動作できるようになっている。しかして、両チョークバー３，４における隣接するチョーク分割片３１，３１同士、ならびにチョーク分割片４１，４１同士は、相互の側面がメタルタッチで直接に接触している。 Here, as shown in FIG. 3, the main channel choke bar 3 and the sub channel choke bar 4 are equally divided into five in the channel width direction in the same division pattern, and each of the choke division pieces 31 is divided. , 41 can be individually moved in and out by the choke operating means 5. Thus, the adjacent choke divided

pieces

31 and 31 and the choke divided

pieces

41 and 41 in both choke

bars

3 and 4 are in direct contact with each other by metal touch.

　各チョーク分割片３１，４１を出退動作させるチョーク操作手段５は、各チョーク分割片３１，４１に内端を固着して外端側がフィードブロック２Ａの外側へ突出したねじ軸５１と、該ねじ軸５１の外端側の雄ねじ部５１ａに螺合した雌ねじ筒５２とで構成されている。そして、雌ねじ筒５２は、フィードブロック２Ａに固着された押さえバー２６によって内端の径大部５２ａが抜け止めされ、もって該フィードブロック２Ａに回転可能で且つ軸方向移動不能に保持されており、その捻回操作でねじ軸５１がチョーク分割片３１，４１と一体に軸方向移動するようになっている。 The choke operating means 5 for moving the choke divided

pieces

31 and 41 back and forth includes a screw shaft 51 whose inner end is fixed to the choke divided

pieces

31 and 41 and the outer end side protrudes outside the feed block 2A, and the screw It is comprised with the internal thread cylinder 52 screwed together by the external thread part 51a of the outer end side of the axis | shaft 51. As shown in FIG. The internal thread cylinder 52 is held by the holding bar 26 fixed to the feed block 2A so that the large-diameter portion 52a at the inner end is prevented from coming off, so that the feed block 2A can rotate and cannot move in the axial direction. The screw shaft 51 moves in the axial direction integrally with the choke divided

pieces

31 and 41 by the twisting operation.

　フィードブロック２Ａの前端の導出口２ａは周囲が凸部２８を形成しており、該凸部２８を連結用プレート２４の後面の凹陥部２４ｂに嵌合すると共に、該連結用プレート２４の前面の凸部２４ａを単層Ｔダイ１の後端の凹陥部１ａに嵌合し、フィードブロック２Ａと単層Ｔダイ１とを該連結用プレート２４を介して連結一体化することにより、導出口２ａがに連通接続する。なお、図１及び図２で示す２７は、フィードブロック２Ａの後端に固着された円板状の口金部材であり、主流路２１の導入口２ａを構成している。 The lead-out port 2a at the front end of the feed block 2A is formed with a convex portion 28, and the convex portion 28 is fitted into the concave portion 24b on the rear surface of the connecting plate 24, and at the front surface of the connecting plate 24. By fitting the convex portion 24a into the recessed portion 1a at the rear end of the single-layer T die 1, and connecting and integrating the feed block 2A and the single-layer T die 1 via the connecting plate 24, the outlet port 2a Connect to the. In addition, 27 shown in FIG.1 and FIG.2 is the disk-shaped nozzle | cap | die member fixed to the rear end of the feed block 2A, and comprises the inlet 2a of the main flow path 21. FIG.

　上記構成の複層押出成形装置では、主流路２１に導入された溶融樹脂流Ｐ１に対し、該主流路２１の同位置における厚み方向両側の合流部２０，２０で、両側の副流路２２，２２から溶融樹脂流Ｐ２，Ｐ３が合流し、合流溶融樹脂流Ｐ１０として単層Ｔダイ１の押出流路１０へ送り込まれ、該単層Ｔダイ１で幅方向に展開されて押出口１１より所要幅の３層の複層フィルムＦとして押し出される。このとき、フィードブロック２Ａ内の主流路２１と各副流路２２との各合流部２０に、幅方向に同じ分割パターンで分割構成された主流路チョークバー３及び副流路チョークバー４とが設けられているから、その各チョーク分割片３１，４１を個別に出退動作することにより、主流路１側及び副流路２側からそれぞれ合流する溶融樹脂流Ｐ１～Ｐ３の厚みを、各チョーク分割片３１，４１に対応する幅方向の区間毎に増減調整できる。 In the multilayer extrusion molding apparatus having the above-described configuration, the molten resin flow P1 introduced into the main flow channel 21 is joined to the sub flow channels 22 on both sides by the joining

portions

20 and 20 on both sides in the thickness direction at the same position of the main flow channel 21. The molten resin streams P2 and P3 merge from 22 and are fed into the extrusion flow path 10 of the single-layer T die 1 as a combined molten resin stream P10 and are developed in the width direction by the single-layer T die 1 and required from the extrusion port 11 Extruded as a three-layer film F with a width of 3 layers. At this time, the main flow path choke bar 3 and the sub flow path choke bar 4 which are divided and configured in the same division pattern in the width direction are formed in the joining portions 20 of the main flow path 21 and the sub flow paths 22 in the feed block 2A. Therefore, the thicknesses of the molten resin flows P1 to P3 that merge from the main flow path 1 side and the sub flow path 2 side can be reduced by moving the choke divided

pieces

31 and 41 individually. Increase / decrease can be adjusted for each section in the width direction corresponding to the divided

pieces

31 and 41.

　しかして、各合流部２０においては、主流路チョークバー３は主流路２１に対して副流路２２側から出退動作するから、前記幅方向の区間単位で、副流路チョークバー４によって調整される副流路２２側の溶融樹脂流Ｐ２又はＰ３の増減に対応して、主流路２１側の溶融樹脂流Ｐ１を副流路２２側から狭めることができ、その狭めることで空いた合流部２０の空間領域に副流路２２側からの溶融樹脂流Ｐ２又はＰ３がそのままスムーズに入り込めるので、主流路２１側からの溶融樹脂流Ｐ１を押し退ける形にはならない。しかも、主流路２１が単層Ｔダイ１の押出流路１０に直線的に連通しており、主流路２１側からの溶融樹脂流Ｐ１は合流部２０で狭められても変化せずに一貫して単層Ｔダイ１の押出流路１０へ向かう直線的な流れを維持するから、この溶融樹脂流Ｐ１の流れに対して両副流路２２，２２側からの溶融樹脂流Ｐ２，Ｐ３が順流として干渉し合うことなく合流し、以降の合流溶融樹脂Ｐ１０は合流部２０，２０での融樹脂流Ｐ１～Ｐ３の乱れのない積層状態を保ったまま単層Ｔダイ１の押出流路１０へ移動してゆく。 Thus, in each merging portion 20, the main flow path choke bar 3 moves out and retracts from the sub flow path 22 side with respect to the main flow path 21, and thus is adjusted by the sub flow path choke bar 4 in the section in the width direction. The molten resin flow P1 on the main flow channel 21 side can be narrowed from the sub flow channel 22 side in response to the increase or decrease of the molten resin flow P2 or P3 on the sub flow channel 22 side, and the merging portion vacated by the narrowing Since the molten resin flow P2 or P3 from the sub-flow channel 22 side can smoothly enter the space area 20 as it is, the molten resin flow P1 from the main flow channel 21 side is not pushed away. Moreover, the main flow path 21 communicates linearly with the extrusion flow path 10 of the single-layer T die 1, and the molten resin flow P1 from the main flow path 21 side does not change even if it is narrowed at the merge portion 20, and is consistent. Since the straight flow toward the extrusion flow path 10 of the single-layer T-die 1 is maintained, the molten resin flows P2 and P3 from both the

secondary flow paths

22 and 22 are forward flowed with respect to the flow of the molten resin flow P1. Then, the merged molten resin P10 is fed to the extrusion channel 10 of the single-layer T die 1 while maintaining the undisturbed laminated state of the molten resin flows P1 to P3 at the

merge portions

20 and 20. Move.

　従って、この複層押出成形装置によれば、樹脂同士の流動特性の差や層同士の厚み差が大きい共押出しに適用した場合でも、両合流部２０，２０において主流路２１及び両副流路２２，２２を幅方向の区間単位で調整した流路断面形状が、押し出された積層フィルムＦの各層の幅方向の厚みに確実に反映することになる。そこで、設定した該流路断面形状と複層フィルムＦの各層の幅方向の厚みプロフィールとの相関から、得られる複層フィルムＦの各層の幅方向の厚みが均一になる流路断面形状を容易に且つ確実に見出すことができ、その見出された最適な流路断面形状を維持することにより、以降は幅方向の各層の厚みが均一な高品位の複層フィルムＦを安定的に連続して製造できる。 Therefore, according to this multi-layer extrusion molding apparatus, even when applied to coextrusion in which the difference in flow characteristics between resins and the difference in thickness between layers are large, the main flow path 21 and both sub flow paths in both merge

portions

20 and 20. The cross-sectional shape of the flow path obtained by adjusting 22 and 22 for each section in the width direction surely reflects the thickness in the width direction of each layer of the extruded laminated film F. Therefore, from the correlation between the set channel cross-sectional shape and the thickness profile in the width direction of each layer of the multilayer film F, the channel cross-sectional shape in which the thickness in the width direction of each layer of the obtained multilayer film F is uniform is easy. By maintaining the optimum flow path cross-sectional shape that has been found, the high-quality multilayer film F having a uniform thickness in the width direction can be stably continued thereafter. Can be manufactured.

　図３の仮想線は流路断面形状の調整例を示している。この場合、主流路チョークバー３の各チョーク分割片３１の突出量を流路幅方向の中央側のものほど大きくし、もって主流路２１の流路断面形状を流路幅方向の中空側ほど狭める一方、副流路チョークバー４の各チョーク分割片４１の突出量を流路幅方向の中央側のものほど小さくし、もって副流路２２の流路断面形状を流路幅方向の中空側ほど拡げる形にしている。なお、主流路２１と副流路２２の流路幅方向の各位置における拡縮の関係は、図３の仮想線による例示の如く概してチョーク分割片３１，４１の幅単位で一方側を狭めて他方側を拡げる形になるが、相互の流路断面の拡縮量は必ずしも一致しない。これは、溶融樹脂流Ｐ１，Ｐ２の流動特性及び供給圧力の違いや、両流路２１，２２間での流路幅方向の流路抵抗及び温度分布の差等により、製出する複層フィルムＦの各層の幅方向の厚みが影響を受けることによる。 The phantom lines in FIG. 3 show examples of adjusting the cross-sectional shape of the flow path. In this case, the amount of protrusion of each choke divided piece 31 of the main flow path choke bar 3 is increased toward the center side in the flow path width direction, thereby narrowing the cross-sectional shape of the main flow path 21 toward the hollow side in the flow path width direction. On the other hand, the amount of projection of each choke divided piece 41 of the sub-channel choke bar 4 is made smaller toward the center side in the channel width direction, so that the channel cross-sectional shape of the sub-channel 22 becomes smaller toward the hollow side in the channel width direction. It has a shape that expands. Note that the expansion / contraction relationship at each position in the channel width direction of the main channel 21 and the sub channel 22 is, as illustrated by the phantom line in FIG. Although the side is expanded, the expansion and contraction amounts of the cross-sections of the flow paths do not always match. This is due to the difference in the flow characteristics and supply pressure of the molten resin streams P1 and P2, the difference in the channel resistance and temperature distribution in the channel width direction between the

channels

21 and 22, and the like. This is because the thickness in the width direction of each layer of F is affected.

　上記第一実施形態では主層の両側に薄い表層を備える３層構造の複層フィルムＦの押出成形に適用する構成を例示したが、本発明の複層押出成形装置は、フィードブロックの流路設定によって２層構造又は４層以上の多層の複層フィルムＦの押出成形にも支障なく適用できる。 In the first embodiment, the configuration applied to the extrusion of the multilayer film F having a three-layer structure having a thin surface layer on both sides of the main layer is exemplified, but the multilayer extrusion molding apparatus of the present invention is a flow path of a feed block. Depending on the setting, the present invention can be applied to the extrusion molding of a multilayer film F having a two-layer structure or four or more layers without any trouble.

　図４に示すフィードブロック２Ｂは、第二実施形態として主層の片側に薄い表層を備えた２層構造の複層フィルムＦを押出成形する複層押出成形装置に用いるもので、前記第一実施形態のフィードブロック２Ａにおける片側の副流路２２を除いた形態であり、単層Ｔダイ１の押出流路１０に直線的に連通する主流路２１と、該主流路２１に対して片側から斜めに合流する副流路２２とを備えている。そして、主流路２１と副流路２２との合流部２０には、第一実施形態と同様に、主流路２１に対して副流路２２側から出退動作する主流路チョークバー３と、副流路２２に対して出退動作する副流路チョークバー４とが設けられている。これら両チョークバー３，４は、第一実施形態と同様に、互いに同一の分割パターンで流路幅方向に５つに等分割されており、その各チョーク分割片３１，４１がチョーク操作手段５によって個別に出退動作できるようになっている（図３参照）。また、合流部２０における主流路２１の最小流路断面積は副流路２２の最大流路断面積よりも大きくなっている。 A feed block 2B shown in FIG. 4 is used in a multilayer extrusion molding apparatus for extruding a multilayer film F having a two-layer structure having a thin surface layer on one side of a main layer as a second embodiment. The feed block 2A of the embodiment is a form excluding the one-side sub-flow path 22, and a main flow path 21 that communicates linearly with the extrusion flow path 10 of the single-layer T-die 1 and is slanted from one side with respect to the main flow path 21 And a sub-flow path 22 that joins the two. In addition, the junction 20 between the main channel 21 and the sub-channel 22 has a main channel choke bar 3 that moves out of the main channel 21 from the side of the sub-channel 22 and the sub-channel 22 as in the first embodiment. A sub-flow channel choke bar 4 that moves in and out of the flow channel 22 is provided. These choke bars 3 and 4 are equally divided into five in the flow path width direction in the same division pattern as in the first embodiment, and the

choke division pieces

31 and 41 are choke operating means 5. Can be individually moved in and out (see FIG. 3). In addition, the minimum channel cross-sectional area of the main channel 21 in the junction 20 is larger than the maximum channel cross-sectional area of the sub-channel 22.

　この第二実施形態の複層押出成形装置では、主流路２１に導入された溶融樹脂流Ｐ１に対し、合流部２０で副流路２２溶融樹脂流Ｐ２が合流し、合流溶融樹脂流Ｐ１０として単層Ｔダイ１の押出流路１０へ送り込まれ、該単層Ｔダイ１で幅方向に展開されて押出口１１より所要幅の２層の複層フィルムＦとして押し出される。このとき、フィードブロック２Ｂ内の合流部２０において、主流路チョークバー３及び副流路チョークバー４の各チョーク分割片３１，４１を個別に出退動作することにより、主流路１側及び副流路２側からそれぞれ合流する溶融樹脂流Ｐ１，Ｐ２の厚みを、各チョーク分割片３１，４１に対応する幅方向の区間毎に増減調整できる。そして、主流路チョークバー３は主流路２１に対して副流路２２側から出退動作するから、前記幅方向の区間単位で、副流路チョークバー４によって調整される副流路２２側の溶融樹脂流Ｐ２の増減に対応して、主流路２１側の溶融樹脂流Ｐ１を副流路２２側から狭めることで空いた空間領域に副流路２２側からの溶融樹脂流Ｐ２がスムーズに入り込めると共に、主流路２１側からの溶融樹脂流Ｐ１は一貫して単層Ｔダイ１の押出流路１０へ向かう直線的な流れを維持するから、この溶融樹脂流Ｐ１に対して溶融樹脂流Ｐ２が順流として干渉し合うことなく合流し、以降の合流溶融樹脂Ｐ１０は乱れのない積層状態で単層Ｔダイ１の押出流路１０へ移動してゆく。 In the multilayer extrusion molding apparatus of the second embodiment, the sub flow channel 22 molten resin flow P2 joins the molten resin flow P1 introduced into the main flow channel 21 at the merging portion 20 to form a single molten molten resin flow P10. It is fed into the extrusion channel 10 of the layer T die 1, developed in the width direction by the single layer T die 1, and extruded from the extrusion port 11 as a double-layer film F having a required width. At this time, the choke divided

pieces

31 and 41 of the main flow path choke bar 3 and the sub flow path choke bar 4 are individually moved out and retracted at the junction 20 in the feed block 2B, so that the main flow path 1 side and the sub flow The thicknesses of the molten resin flows P1 and P2 that merge from the path 2 side can be increased or decreased for each section in the width direction corresponding to each of the choke divided

pieces

31 and 41. Since the main channel choke bar 3 moves out and retracts from the sub channel 22 side with respect to the main channel 21, the sub channel 22 side adjusted by the sub channel choke bar 4 is adjusted in units of the width direction. Corresponding to the increase or decrease of the molten resin flow P2, the molten resin flow P1 from the sub-channel 22 side can smoothly enter the vacant space region by narrowing the molten resin flow P1 on the main channel 21 side from the sub-channel 22 side. At the same time, the molten resin flow P1 from the main flow path 21 side maintains a linear flow toward the extrusion flow path 10 of the single-layer T-die 1 consistently, so that the molten resin flow P2 corresponds to the molten resin flow P1. As a forward flow, they merge without interfering with each other, and the subsequent merged molten resin P10 moves to the extrusion flow path 10 of the single-layer T die 1 in an undisturbed layered state.

　従って、この第二実施形態の複層押出成形装置においても、合流部２０において主流路２１及び副流路２２を幅方向の区間単位で調整した流路断面形状が、押し出された積層フィルムＦの各層の幅方向の厚みに確実に反映することになり、設定した該流路断面形状と複層フィルムＦの各層の幅方向の厚みプロフィールとの相関から、得られる複層フィルムＦの各層の幅方向の厚みが均一になる流路断面形状を容易に且つ確実に見出すことができ、以降は最適な流路断面形状を固定化して幅方向の各層の厚みが均一な高品位の複層フィルムＦを安定的に連続して製造できる。 Therefore, also in the multilayer extrusion molding apparatus of this second embodiment, the flow path cross-sectional shape in which the main flow path 21 and the sub flow path 22 are adjusted in the section unit in the width direction in the joining portion 20 is the same as that of the extruded laminated film F. The width of each layer of the obtained multilayer film F is surely reflected in the thickness in the width direction of each layer, and is obtained from the correlation between the set channel cross-sectional shape and the thickness profile in the width direction of each layer of the multilayer film F. It is possible to easily and surely find a channel cross-sectional shape with a uniform thickness in the direction, and thereafter fix the optimal channel cross-sectional shape and a high-quality multilayer film F in which the thickness of each layer in the width direction is uniform. Can be manufactured stably and continuously.

　本発明の複層押出成形装置においては、フィードブロックにおける主流路２１に対して複数本の副流路２２を合流させる構成において、各合流部を主流路２１における流路方向の異なる位置に設定してもよい。この場合でも、各副流路２の合流部２０毎に前記分割構成の主流路チョークバー３及び副流路チョークバー４を第二実施形態の如く配置することにより、３層以上の複層フィルムＦとして、各層の幅方向の厚みが均一なものを確実に且つ安定的に製造することが可能となる。ただし、３層以上の多層の複層フィルムの押出成形では、一対あるいは複数対の副流路２２，２２を第一実施形態のように主流路２１に対して厚み方向両側から同位置で斜めに合流する形にすることにより、フィードブロックをコンパクトに機能的に構成できるという利点がある。 In the multilayer extrusion molding apparatus of the present invention, in the configuration in which a plurality of sub-channels 22 are merged with respect to the main channel 21 in the feed block, each merging portion is set at a different position in the channel direction in the main channel 21. May be. Even in this case, by arranging the divided main flow choke bar 3 and sub flow choke bar 4 for each merging portion 20 of each sub flow channel 2 as in the second embodiment, a multilayer film having three or more layers is provided. As F, it is possible to reliably and stably manufacture a layer having a uniform thickness in the width direction of each layer. However, in extrusion molding of a multilayer film of three or more layers, a pair or a plurality of pairs of

sub-channels

22 and 22 are inclined at the same position from both sides in the thickness direction with respect to the main channel 21 as in the first embodiment. By combining the shapes, there is an advantage that the feed block can be configured in a compact and functional manner.

　主流路チョークバー３及び副流路チョークバー４は、第一及び第二実施形態では５つに等分割しているが、その分割数及び分割パターンは種々変更可能である。ただし、分割数については、副層フィルムの幅方向中央部と両側部との厚みプロフィールを設定する上で３分割以上にする必要がある。また、主流路チョークバー３と副流路チョークバー４の分割は、幅方向の分割区間単位で合流部２０の流路断面形状と副層フィルムの厚みプロフィールとの相関を検出する必要から、同一パターンに設定する必要がある。 The main channel choke bar 3 and the sub channel choke bar 4 are equally divided into five in the first and second embodiments, but the number of divisions and the division pattern can be variously changed. However, the number of divisions needs to be three or more in order to set the thickness profile of the center portion in the width direction and both side portions of the sublayer film. Further, the division of the main channel choke bar 3 and the sub channel choke bar 4 is the same because it is necessary to detect the correlation between the channel cross-sectional shape of the merging portion 20 and the thickness profile of the sub layer film in units of division sections in the width direction. Must be set to pattern.

　なお、第一及び第二実施形態のように、主流路２１に対して傾斜配置した主流路チョークバー３の片側側面３ｂが副流路２２の片側流路壁をなす構造では、この主流路チョークバー３の先端前方が合流点となり、該チョークバー３にて主流路２１が断面調整された位置に副流路２２側からの溶融樹脂流Ｐ２又はＰ３がそのまま合流し、合流部２０における流れの相互干渉がより効果的に抑えられると共に、主流路チョークバー３による主流路２１の溶融樹脂流Ｐ１への抵抗が傾斜配置によって小さくなるという利点がある。また、一般的にフィードブロックは複数の金型部材を組み合わせて構成するが、実施形態の構造では、副流路２２に臨んで金型分離面を設定することにより、簡素で且つ機能的な部材構成に容易に設定できるという利点もある。 In the structure in which the one side surface 3b of the main channel choke bar 3 inclined with respect to the main channel 21 forms the one side channel wall of the sub channel 22 as in the first and second embodiments, this main channel choke The front end of the bar 3 serves as a merge point, and the molten resin flow P2 or P3 from the sub-flow channel 22 side merges directly at the position where the cross section of the main flow channel 21 is adjusted by the choke bar 3, and the flow at the merge portion 20 Mutual interference is more effectively suppressed, and there is an advantage that the resistance of the main flow path choke bar 3 to the molten resin flow P1 of the main flow path 21 is reduced by the inclined arrangement. In general, the feed block is configured by combining a plurality of mold members. However, in the structure of the embodiment, a simple and functional member is formed by setting the mold separation surface facing the sub-channel 22. There is also an advantage that the configuration can be easily set.

　更に、第一及び第二実施形態のように、フィードブロック２Ａ，２Ｂの合流部２０における主流路２１の最小流路断面積は副流路２２の最大流路断面積よりも大きい場合、副流路２２側からの溶融樹脂流Ｐ２は主流路２１側からの溶融樹脂流Ｐ１よりも流量が少なくなって本来は乱され易いが、上記の両流路２１，２２と両チョークバー３，４の配置構成によって乱れが確実に抑えられるから、主層に対して薄い副層が積層した複層フィルムとして高品位のものを安定的に製造できる。 Furthermore, as in the first and second embodiments, when the minimum channel cross-sectional area of the main channel 21 in the merge portion 20 of the feed blocks 2A and 2B is larger than the maximum channel cross-sectional area of the sub-channel 22, The molten resin flow P2 from the path 22 side has a smaller flow rate than the molten resin flow P1 from the main flow path 21 side and is inherently disturbed, but the

flow paths

21 and 22 and the choke bars 3 and 4 Since the disturbance can be reliably suppressed by the arrangement configuration, a high-quality film can be stably manufactured as a multilayer film in which a thin sublayer is laminated on the main layer.

　一方、チョーク操作手段５については、実施形態で例示した以外の種々の構造を採用できるが、実施形態のように各チョーク分割片３１，４１に内端を固着して外端側がフィードブロック２Ａの外側へ突出したねじ軸５１と、該ねじ軸５１の外端側の雄ねじ部５１ａに螺合した雌ねじ筒５２とで構成すれば、主流路チョークバー３及び副流路チョークバー４の各チョーク分割片３１，４１の出退調整を容易に確実に行えると共に、フィードブロック２が構造簡単になる。 On the other hand, the choke operating means 5 can employ various structures other than those exemplified in the embodiment. However, as in the embodiment, the inner end is fixed to each of the choke divided

pieces

31 and 41, and the outer end side is the feed block 2A. If the screw shaft 51 protruding outward and the female screw cylinder 52 screwed into the male screw portion 51a on the outer end side of the screw shaft 51 are configured, each choke division of the main flow path choke bar 3 and the sub flow path choke bar 4 is performed. It is possible to easily and reliably adjust the withdrawal of the

pieces

31 and 41, and the structure of the feed block 2 is simplified.

　また、チョーク操作手段５として、その操作を機械的に制御してμｍ単位の微量調整を可能にする構成としてもよい。例えば、実施形態で例示した雌ねじ筒５２の回転をギヤ機構等を介して機械的に精密に駆動制御したり、チョーク分割片３１，４１に連結した押し軸に伝熱するヒーターを設け、該ヒーターの加熱による押し軸の熱膨張の度合でチョーク分割片３１，４１の進退量を微量調整することも可能である。 Further, the choke operating means 5 may be configured to mechanically control the operation to enable a minute adjustment in units of μm. For example, the rotation of the female screw cylinder 52 exemplified in the embodiment is mechanically and precisely driven and controlled via a gear mechanism or the like, or a heater that transfers heat to the push shaft connected to the choke divided

pieces

31 and 41 is provided. It is also possible to finely adjust the amount of advance and retreat of the choke divided

pieces

31 and 41 by the degree of thermal expansion of the push shaft by heating.

　その他、本発明の複層押出成形装置では、フィードブロックと単層Ｔダイとの連結構造、フィードブロックにおける各流路の導入口の配置、フィードブロック及び単層Ｔダイの細部構成等について、実施形態以外に種々設計変更可能である。 In addition, in the multilayer extrusion molding apparatus of the present invention, the connection structure between the feed block and the single layer T die, the arrangement of the inlets of each flow path in the feed block, the detailed configuration of the feed block and the single layer T die, etc. Various design changes can be made in addition to the form.

　本発明の複層押出成形装置は、単一のフィードブロックにより、各層の厚み比率及び樹脂材料が異なる複層フィルムついて、いずれも各層の幅方向の厚みが均一な高品位なものを安定的に押出成形できるから、同じフィードブロックと単層Ｔダイの組合せでも複数種の複層フィルム製品の製造に利用可能であるが、その組合せを変えることで更にフィルムの幅と総厚、層数、各層の厚み等が種々異なる多品種の複層フィルム製品の製造に対応できる。また、単一品種で量産が必要な複層フィルムについては、本発明の複層押出成形装置をパイロット装置として利用し、これによって判明したフィードブロックの合流部における最適な流路断面形状から、チョーク分割片３１，４１の隣接部の段差を均す形で非分割形態の主流路チョークバー及び副流路チョークバーを設計製作し、これら非分割形態のチョークバーを合流部に同様に組み込んだフィードブロックを用いて工業規模の量産を行うこともできる。 The multi-layer extrusion molding apparatus of the present invention can stably provide a high-quality film having a uniform thickness in the width direction of each layer for a multi-layer film having a different thickness ratio and resin material of each layer by a single feed block. Because it can be extruded, the same feed block and single layer T-die combination can be used to produce multiple types of multilayer film products. By changing the combination, the film width and total thickness, the number of layers, and each layer It can cope with the manufacture of multi-layered film products with various thicknesses. For multi-layer films that require mass production with a single product type, the multi-layer extrusion molding apparatus of the present invention is used as a pilot apparatus, and the choke shape determined from the optimum flow path cross-sectional shape at the junction of the feed block is determined. A non-divided main channel choke bar and a sub-channel choke bar are designed and manufactured by leveling the steps at the adjacent portions of the divided

pieces

31 and 41, and the non-divided form choke bar is similarly incorporated into the junction. Industrial scale mass production can also be performed using blocks.

　１　　　　　単層Ｔダイ
　１０　　　　押出流路
　１１　　　　押出口
　２Ａ，２Ｂ　フィードブロック
　２０　　　　合流部
　２１　　　　主流路
　２２　　　　副流路
　３　　　　　主流路チョークバー
　３ｂ　　　　外側側面
　３１　　　　チョーク分割片
　４　　　　　副流路チョークバー
　４１　　　　チョーク分割片
　５　　　　　チョーク操作手段
　５１　　　　ねじ軸
　５２　　　　雌ねじ筒
　Ｆ　　　　　複層フィルム
　Ｐ１～Ｐ３　溶融樹脂流
　Ｐ１０　　　合流溶融樹脂流 DESCRIPTION OF SYMBOLS 1 Single layer T die 10 Extrusion flow path 11

Extrusion port

2A, 2B Feed block 20 Merge part 21 Main flow path 22 Sub flow path 3 Main flow path choke bar 3b Outer side surface 31 Choke division piece 4 Sub flow passage choke bar 41 Choke division piece 5 Choke operating means 51 Screw shaft 52 Female thread cylinder F Multi-layer film P1 to P3 Molten resin flow P10 Merged molten resin flow

Claims

　単層Ｔダイの上流側にフィードブロックが連結され、複数の溶融樹脂流をフィードブロックで合流させ、その合流溶融樹脂を単層Ｔダイから押し出して複層フィルムを製出する複層押出成形装置において、
　前記フィードブロックは、単層Ｔダイの押出流路に直線的に連通する偏平な主流路と、該主流路に対して同幅で斜めに合流する偏平な副流路とを備え、
　該フィードブロックの前記主流路と副流路との合流部に、主流路に対して副流路側から出退動作して当該主流路の流路断面積を厚み方向に拡縮する主流路チョークバーと、副流路に対して出退動作して当該副流路の流路断面積を厚み方向に拡縮する副流路チョークバーとが設けられ、
　前記主流路チョークバーと副流路チョークバーとが共に同一の分割パターンで幅方向に３以上に分割構成され、その各チョーク分割片を個別に出退動作させるチョーク操作手段を有することを特徴とする複層押出成形装置。 A multi-layer extrusion molding apparatus in which a feed block is connected to the upstream side of a single-layer T die, a plurality of molten resin flows are merged by the feed block, and the combined molten resin is extruded from the single-layer T die to produce a multi-layer film In
The feed block includes a flat main channel that communicates linearly with the extrusion channel of the single-layer T-die, and a flat sub-channel that merges obliquely with the same width with respect to the main channel,
A main flow path choke bar for moving the cross-sectional area of the main flow path in the thickness direction by moving back and forth from the sub flow path side with respect to the main flow path at the junction of the main flow path and the sub flow path of the feed block; A sub-channel choke bar that moves back and forth with respect to the sub-channel and expands / contracts the channel cross-sectional area of the sub-channel in the thickness direction,
The main flow path choke bar and the sub flow path choke bar are both divided into three or more in the width direction in the same division pattern, and have choke operation means for individually moving the choke divided pieces in and out. Multi-layer extrusion molding equipment.
　前記主流路チョークバーが副流路に沿って出退動作するように主流路に対して傾斜配置すると共に、この主流路チョークバーの外側側面が該副流路の幅方向に沿う片側流路壁を構成してなる請求項１に記載の複層押出成形装置。 The main flow path choke bar is inclined with respect to the main flow path so that the main flow path choke bar moves back and forth along the sub flow path, and the outer side surface of the main flow path choke bar extends along the width direction of the sub flow path. The multilayer extrusion molding apparatus according to claim 1, comprising:
　前記主流路に対して複数本の副流路が合流し、各副流路の合流部毎に前記主流路チョークバー及び副流路チョークバーが配置してなる請求項１に記載の複層押出成形装置。 2. The multilayer extrusion according to claim 1, wherein a plurality of sub-flow paths merge with the main flow path, and the main flow-path choke bar and the sub-flow path choke bar are arranged at each merging portion of each sub-flow path. Molding equipment.
　前記主流路に対して少なくとも一対の副流路が該主流路の厚み方向両側から同位置で合流し、その厚み方向両側の合流部に各々対応して前記主流路チョークバー及び副流路チョークバーが配置してなる請求項３に記載の複層押出成形装置。 At least a pair of sub-channels merges at the same position from both sides in the thickness direction of the main channel with respect to the main channel, and the main channel choke bar and the sub-channel choke bar respectively correspond to the merging portions on both sides in the thickness direction. The multilayer extrusion molding apparatus according to claim 3, which is arranged.
　前記フィードブロックの合流部における主流路の最小流路断面積が副流路の最大流路断面積よりも大きく設定されてなる請求項１に記載の複層押出成形装置。 2. The multilayer extrusion molding apparatus according to claim 1, wherein a minimum channel cross-sectional area of the main channel at the junction of the feed blocks is set larger than a maximum channel cross-sectional area of the sub-channel.
　前記チョーク操作手段は、前記各チョーク分割片に内端を固着して外端側がフィードブロックの外側へ突出したねじ軸と、該ねじ軸の外端側の雄ねじ部に螺合し、フィードブロックに回転可能で且つ軸方向移動不能に保持された雌ねじ筒とで構成され、該雌ねじ筒の捻回操作で前記ねじ軸を軸方向移動するように構成されてなる請求項１～５の何れかに記載の複層押出成形装置。 The choke operating means has an inner end fixed to each of the choke divided pieces, and a screw shaft whose outer end side protrudes to the outside of the feed block and a male screw portion on the outer end side of the screw shaft, and is screwed into the feed block. 6. The internal thread cylinder that is rotatable and is held so as not to be axially movable, and is configured to axially move the threaded shaft by a twisting operation of the internal thread cylinder. The multilayer extrusion molding apparatus described.