JP3924194B2 - Manufacturing method of sheet-like extruded product and extrusion molding apparatus used therefor - Google Patents

Description

【００３９】
上記構成の変性用スクリュー押出機に、まず、ポリオレフィン系樹脂及びジオキシム化合物を別々のホッパーから定量供給し、両者を溶融混和し、変性樹脂を得た。
ポリオレフィン系樹脂としては、ポリプロピレンランダム共重合体（三菱化学社製「ＥＧ８」）を用い、その供給量は５０ｋｇ／ｈとした。
変性用モノマーとしては、ｐ−キノンジオキシム（大内新興化学社製「バルノックＧＭ−Ｐ」）を用い、その供給量はポリオレフィン系樹脂１００重量部に対して０．８重量部とした。
ポリオレフィン系樹脂と変性用モノマーの溶融混和によって得られた変性樹脂を、接続フランジを介して後述の発泡剤混練用押出機の第５シリンダーに吐出した。
【００４０】
（２）発泡性樹脂組成物の調製
発泡剤混練用スクリュー押出機として、ＴＥＸ−６５型（日本製鋼所社製）同方向回転２軸スクリュー押出機を用いた。この押出機はセルフワイピング２条スクリューを備え、そのＬ／Ｄは４５．５、Ｄは６９ｍｍである。シリンダーは押出機の上流側から下流側へ第１〜１３シリンダーからなり、シートダイは幅１６００ｍｍ、リップ間隔０．６ｍｍのＴダイである。
温度設定区分は下記の通りとした。
第１シリンダーは常時冷却
第１ゾーン：第２〜５シリンダー
第２ゾーン：第６〜第８シリンダー
第３ゾーン：第９〜第１３シリンダー
第４ゾーン：ダイ及びアダプター部
【００４１】
この発泡剤混練用スクリュー押出機には、変性用スクリュー押出機からの変性樹脂を供給するためのフランジが第５シリンダーに接続してあり、発泡剤を供給するために第８シリンダーにサイドフィーダーが設置され、揮発分を回収するため第１１シリンダーに真空ベントが設置されている。
操作条件は下記の通りとした。

【００４２】
発泡剤混練用スクリュー押出機の第１シリンダーにはブレンド用樹脂としてポリオレフィン系樹脂を、また前述の変性樹脂を変性用スクリュー押出機から接続フランジを介して発泡剤混練用スクリュー押出機の第５シリンダーに供給した。ブレンド用のポリオレフィン系樹脂としては、ホモタイプポリプロピレン（三菱化学社製「ＭＡ３」）を用い、その供給量は５０ｋｇ／ｈとした。また、同押出機にそのサイドフィーダから発泡剤を供給し、分散させた。発泡剤としては、アゾジカルボンアミド（ＡＤＣＡ）を用い、その供給量は４ｋｇ／ｈとした。
【００４３】
（３）シート状押出成形品の成形
こうして変性樹脂とブレンド樹脂と発泡剤の混練によって得られた発泡性樹脂組成物を、押出成形装置の押出機、アダプター内を経て、Ｔダイから押し出し、３本冷却ロールを通して冷却し、幅Ｌ＝１５４０ｍｍ、厚さ０．７ｍｍのシート状押出成形体２′を得た。
【００４４】
この際、図４に示すように、冷却ロールを通過した後のシート状押出成形体２′の両側縁部における、廃棄部分を切り離す第１スリット位置Ｂ１，Ｂ２を、表１に示す位置となすとともに、第１スリット位置Ｂ１，Ｂ２よりも内側であって、回収原料として利用する部分を切り離す第２スリット位置Ｃ１，Ｃ２を、シート状押出成形体２′の両側縁Ａ１，Ａ２からの幅Ａ１−Ｃ１，Ａ２−Ｃ２がシート状押出成形体２′の全幅Ｌに対して表１に示す位置となして、所定幅（Ｃ１−Ｃ２）のシート状押出成形品２を得た。
一次発泡部Ｈを含む廃棄部分は廃棄し、一次発泡部は含まずフローマークＦを含む第１スリット位置と第２スリット位置との間の部分Ｂ１−Ｃ１，Ｂ２−Ｃ２を粉砕後、回収原料として発泡剤、混練用スクリュー押出機の第１シリンダーに定量供給した。
【００４５】
スクリューヘッドとアダプターとしては、表１に示す寸法関係のものを用いた。
スクリューヘッド最先端から近接するアダプター流路側壁面までの距離の測定は次のように行った。
押出機のスクリュー本体部、スクリューヘッド、シリンダーを成形温度まで昇温し、図５に示すように、押出機のシリンダー１１にボルト１５（入れ子固定用）を用いて流路入れ子１２４を装着した。この際、スクリューヘッド１４２最先端と流路入れ子１２４流路側壁面の相対位置はスペーサー１４３により調節した。そして、流路入れ子１２４の出口側から内部を覗き込み、距離Ｘを測定した。
【００４６】
図１〜図３を参照して説明した方法に準じて、押出成形装置１の起動前に押出機のシリンダー１１とアダプター１２′間を分離した状態で成形温度まで上昇終了後に、押出機のシリンダー１１とアダプター１２′間を接続した状態となして、押出成形装置１の起動を行い、押出成形時にスクリューヘッドの先端部近傍の空間Ｋ，Ｋにて樹脂が滞留することにより生じるフローマークＦ，Ｆの位置を、シートダイ１３にて賦形した押出成形体２′の両側縁によせるように押出成形を行った。
【００４７】
押出成形終了後、樹脂の吐出を停止し、押出機のシリンダー１１とアダプター１２′とを分離して、それらの冷却を行った。
【００４８】
（４）複合シートの調製と発泡
シート状押出成形品２の表面及び裏面に、ポリエチレンテレフタレート製の不織布（東洋紡績社製、「スパンボンド エクーレ ６３０１Ａ」、坪量３０ｇ／ｍ² 、引張強度：縦１．６ｋｇ／ｃｍ、横１．２ｋｇ／ｃｍ）を熱融着し、ポリオレフィン系樹脂発泡性複合シートを得た。
得られたポリオレフィン系樹脂発泡性複合シートを加熱ゾーンを有する連続発泡機にて、２２０℃で約５分間熱発泡させ、約１０ｃｃ／ｇの倍率の複合発泡体を得た。
【００４９】
（５）性能評価
得られた複合発泡体について、下記の項目の性能評価を行った。
・製品としての有効幅測定：
複合発泡体について、フローマーク部を除いた製品有効幅を測定した。
・製品としての一次発泡幅測定：
発泡前の複合シートについて、最端部に発生した一次発泡幅（片側）を測定した。
【００５０】
実施例２
シート状押出成形品の成形（３）において、スクリューヘッドとアダプターとして、表１に示す寸法関係のものを用いたこと以外は実施例１と同様にして、得られた複合発泡体について性能評価を行った。その結果を表１に示す。
【００５１】
比較例
シート状押出成形品の成形（３）において、スクリューヘッドとアダプターとして、表１に示す寸法関係のものを用いたこと以外は実施例１と同様にして、得られた複合発泡体について性能評価を行った。その結果を表１に示す。
【００５２】
【表１】

【００５３】
表１からも明らかなように、本発明の実施例の場合には、比較例の場合に比べて、一次発泡部の幅は若干大きくなるものの、大きな製品有効幅を確保することができた。
【００５４】
【発明の効果】
本発明のシート状押出成形品の製造方法は、上記の構成とされているので、スクリューヘッドの先端部やアダプター流路側壁面を損傷するおそれがなく、フローマークの位置をシート状押出成形体の両側縁によせるように押出成形を行うことができる。
【００５５】
本発明の押出成形装置は、上記の構成とされているので、成形時にスクリューヘッドの先端部とアダプター流路側壁面との距離が小さくなるように組み付けることができる。
【図面の簡単な説明】
【図１】 本発明のシート状押出成形品の製造方法の一例を、本発明の押出成形装置の一例とともに説明する水平断面図である。
【図２】（ａ）〜（ｇ）は、それぞれ、図１のａ〜ｇ部分における縦断面図である。
【図３】 図１に示す押出成形装置の起動前の状態を示す水平断面図である。
【図４】 本発明のシート状押出成形品の製造方法の一例におけるシート状押出成形体の両側縁部のスリット状況を説明する平面図である。
【図５】 本発明に使用されるアダプターの別の例を示す断面図である。
【図６】 図５に示すアダプターを備えた押出成形装置の起動前の状態を示す縦断面図である。
【図７】 従来の押出成形装置を用いたシート状押出成形品の製造方法の一例を説明する水平断面図である。
【符号の説明】
１ 押出成形装置
１１ シリンダー
１２ アダプター
１３ シートダイ
１４ スクリュー
１４２ スクリューヘッド[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing an extruded product and an adapter used therefor.
[0002]
[Prior art]
In the extrusion molding, as shown in FIG. 7, the resin stays in the space K beyond the tip of the screw S in the extruder, and as a result, the side edge of the both sides of the extrusion molded product sheet is considerably inside. A streak called a flow mark F appears along the longitudinal direction.
Conventionally, in order to suppress this phenomenon, for example, as described in JP-A-56-150526 and JP-A-4-339632, a breaker plate and an adapter have been modified.
[0003]
However, in the method of remodeling the breaker plate and the adapter, the flow mark is not completely erased from the molded product produced by extrusion molding. For example, when a foamable sheet produced by extrusion molding is foamed, the flow mark generated by the residence of the resin does not disappear completely, and there are adverse effects such as lowering the strength of the product and poor appearance.
If a product is produced excluding the side portion including the flow mark portion, the effective product width becomes narrow, there is a problem in terms of cost, and a wide product cannot be manufactured.
[0004]
In view of this point, for example, as described in Japanese Patent Application Laid-Open No. 2000-150510, the flow mark is moved to both side edge portions of the sheet by reducing the distance between the tip portion of the screw head and the side wall surface of the adapter channel adjacent thereto. It has been proposed to widen the effective range of products.
This method has been found to have the following problems when applied to large-scale mass production facilities.
[0005]
That is, in a large extruder, a refrigerant such as oil or water is often circulated in the screw in order to prevent excessive heat generation of the resin. However, in the extruder at the time of molding as compared with normal temperature, the cylinder becomes hot, the cylinder expands due to the thermal expansion of the metal, and as a result, the adapter moves downstream in the extrusion direction.
[0006]
On the other hand, the screw is cooled, and the amount of movement of the screw head is smaller than the expansion of the cylinder. For this reason, the distance between the tip of the screw and the side wall surface of the adapter channel is relatively increased as compared with the normal temperature. Therefore, even if the distance between the screw head and the side wall surface of the adapter channel is as close to 0 as possible when the adapter is assembled, the gap is widened during molding, and the movement of the flow mark to both side edges becomes insufficient. Conversely, if the assembly is performed such that the distance between the screw head and the side wall surface of the adapter flow path becomes small during molding, the gap becomes 0 or less when the extruder is stopped (normal temperature state), and the screw head or adapter may be damaged. became.
For example, in a large extruder having a screw length of more than 5 m, when a temperature difference between the cylinder and the screw of about 100 ° C. occurs, the screw head moves backward in the direction opposite to the extrusion direction by about 5 mm as compared to normal temperature. Cases are observed.
[0007]
[Problems to be solved by the invention]
  INDUSTRIAL APPLICABILITY The present invention solves the conventional problems as described above, and a method for producing a sheet-like extrusion molded article capable of obtaining a wide product with high productivity with a large-scale mass-production extruder and is used for the same.Extrusion equipmentIt was made for the purpose of providing.
[0008]
[Means for Solving the Problems]
  The invention according to claim 1 is a method of manufacturing an extruded product using an extrusion molding apparatus including an adapter between a cylinder of the extruder and a sheet die, and the cylinder of the extruder before the startup of the extrusion molding apparatus. And the process of raising the molding temperature with the adapter separated, and connecting the two after the temperature riseThe extrusion molding is performed in such a state that the width from the most advanced position of the screw head of the extruder to the closest adapter channel side wall surface is 0.1 to 5% of the width between the opposing adapter channel side wall surfaces. Start up the device and shape it with the sheet dieA sheet-like extrusion comprising: a step of performing extrusion molding; and a step of stopping resin discharge after completion of the extrusion molding, separating the cylinder of the extruder and the adapter, and cooling them. It is a manufacturing method of a molded article.
[0009]
According to a second aspect of the present invention, the first slit position at which the waste portion is cut off at both side edges of the sheet-like extrudate is defined by the width from both sides of the sheet-like extrudate. The second slit position is 0.1-5% with respect to the entire width, and is located inside the first slit position and cuts off the portion used as the recovered raw material. The width from both side edges becomes a position where it becomes 1 to 15% with respect to the total width of the sheet-like extruded product, the discarded portion is discarded, and the portion between the first slit position and the second slit position Is a method for producing a sheet-like extruded product according to the first aspect of the present invention, wherein a raw material resin is mixed with a raw material resin of an extruder.
[0010]
  The invention according to claim 3 is:PushBetween the cylinder of the machine and the sheet dieAn adapter is interposed,The width from the foremost position of the screw head of the extruder to the nearest adapter channel side wall surface during extrusion in the connected state is 0.1 to 5 of the width between the opposing adapter channel side wall surfaces. %, And can be moved back and forth in the axial direction of the screw with respect to the cylinder of the extruder,StartBefore moving the cylinder of the extruderEach with an adapterIncreased to molding temperature in a separated stateMade possibleAfter heating up,BothTo be connected and start upDoneIt is characterized byExtrusion equipmentIt is.
[0011]
The resin used in the present invention is not particularly limited, and examples thereof include olefin resins such as polyethylene, polypropylene, and ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, acrylonitrile-styrene copolymer. Examples thereof include coalescence, polystyrene, (meth) acrylic resin, polyamide, polycarbonate, thermoplastic polyester, and thermoplastic elastomer powder rubber. These may be used alone or in combination of two or more.
[0012]
In the present invention, in the resin, if necessary, additives such as fillers, lubricants, stabilizers, flame retardants, antiblocking agents, antifoaming agents, pigments, dyes, and the like do not impair the purpose of the present invention. May be added.
[0013]
In the present invention, the extruder is not particularly limited, and one, two or more axes or a combination thereof can be used. In the case of two axes, the screw rotation direction may be the same direction, It may be in the reverse direction. Further, the meshing type or the non-meshing type may be used. The shaft type may be a parallel type or a conical type. Moreover, you may use the tandem system which combined the extruder in multiple stages. However, in the case of a single shaft, it is necessary to offset the axis of the adapter with respect to the extruder in order to make the distance between the tip of the screw head and the side wall surface of the adapter channel close.
[0014]
The adapter used in the present invention is not particularly limited as long as the gap between the flow path side wall surface and the screw head can be realized within a desired range. I can't see how much it is. Therefore, for example, as shown in FIG. 5, the flow path in the portion close to the screw head is set as a nesting system, and the nesting is assembled to the extruder before connecting the adapter to the extruder, so that the flow path is inserted from the outlet side. It is preferable to be able to confirm the gap with the screw head. Furthermore, it is desirable that this gap can be confirmed in an elevated temperature of the extruder and the adapter (including the flow path insert), and the gap sandwiches a spacer between the extruder and the adapter (including the flow path insert). It is preferable that fine adjustment is possible.
[0015]
The sheet die used in the present invention is not particularly limited, and examples thereof include a T die, an L die, a coat hanger die, a fish tail die, and the like, and may be a single layer or a multilayer. Absent. In addition, a thin pipe die may be used to cut out a part after discharging from the die and shape the sheet.
[0016]
In the present invention, the staying portion generated at the tip of the screw head is generated at both side edges of the sheet. By suppressing the staying at the tip of the screw head as much as possible, the absolute flow mark portion generated at the sheet is prevented. It is possible to reduce the amount. For this reason, it is preferable that the tip of the screw head has a structure in which the resin does not easily stay at the tip, for example, an acute structure. Furthermore, it is preferable that the tip portion of the screw head portion is replaced with an exchange system so that the screw head portion can be recovered immediately even if the screw head portion interferes with the adapter flow path wall surface due to trouble or the like and is damaged and deformed.
[0017]
In the present invention, a breaker plate, a screen mesh, or the like may be added between the extruder, the adapter, and the sheet die. However, when these are added, the resin flow path before entering the sheet die Care must be taken not to disturb the position of the outermost flow mark.
[0018]
The mechanism for moving the adapter in parallel with the screw axis direction is not particularly limited. For example, a system in which the adapter and the die base are placed on the rail and slid in parallel with the screw axis is preferable from the viewpoint of workability.
[0019]
In this invention, the width | variety from the both-sides edge of a sheet-like extrusion molding body is 0.1 with respect to the full width of a sheet-like extrusion molding body in the 1st slit position which cuts off a waste part in the both-side edge part of a sheet-like extrusion molding body. It is preferable that the position is set to ˜5%.
This waste part is a part including a primary foaming part including a decomposition residual of the foaming agent due to primary foaming. Therefore, the use of this as a recovered raw material deteriorates the foaming characteristics of the sheet-like extruded product, so this part needs to be discarded.
When the first slit position is less than 0.1% with respect to the entire width, there is very little need to cut only this portion, and when it exceeds 5%, the raw material efficiency in the sheet width direction is deteriorated.
[0020]
Further, the second slit position, which is inside the first slit position and cuts off the portion used as the recovered raw material, has a width from both side edges of the sheet-like extruded product of 1 with respect to the entire width of the sheet-like extruded product. It is preferable to set the position at -15%.
When the second slit position is less than 1% with respect to the entire width, the primary foaming portion is likely to be mixed. When the second slit position exceeds 15%, the amount of the recovered raw material to be fed into the extruder is too large for the processing capacity of the extruder, It is difficult to make full use of production capacity.
[0021]
  Of the present inventionThe extrusion molding equipmentIn the state of being connected so as to be interposed between the cylinder of the unloader and the sheet die, the width from the most advanced position of the screw head of the extruder to the nearest adapter channel side wall surface during the extrusion is opposite to the width. It is necessary to be 0.1 to 5% of the width between the side walls of the adapter channel.
  If the width is less than 0.1%, there is a possibility of interference with the flow path side wall surface due to the runout of the screw head, etc., and if it exceeds 5%, the flow mark appearing on the sheet is more difficult on the side edges.
[0022]
[Action]
  The method for producing the sheet-like extruded product of the present invention is as follows.As the state where the width from the most advanced position of the screw head of the extruder to the nearest adapter channel side wall surface is 0.1 to 5% of the width between the opposite adapter channel side wall surfaces of the extruder, Start up and shape with the sheet dieA step of performing extrusion molding, and a step of stopping the discharge of the resin after completion of the extrusion molding, separating the cylinder of the extruder and the adapter, and cooling them. In the state before the temperature rise with the adapters separated, the tip of the screw head is in contact with the side wall surface of the adapter channel even if the cylinder is greatly contracted compared to the length of the cooled screw head. Therefore, they can be prevented from being damaged and can be assembled so that the distance between the tip of the screw head and the side wall surface of the adapter flow path becomes small when connected after the temperature rise. Further, the extrusion can be performed so that the position of the flow mark is located on both side edges of the sheet-like extruded product.
[0023]
Further, in the molding step, the first slit position at which the waste portion is cut off at both side edges of the sheet-like extrusion molded body is defined such that the width from the both side edges of the sheet-like extrusion molding body is the width of the sheet-like extrusion molding body. The second slit position is 0.1-5% with respect to the entire width, and is located inside the first slit position and cuts off the portion used as the recovered raw material. The width from both side edges becomes a position where it becomes 1 to 15% with respect to the total width of the sheet-like extruded product, the discarded portion is discarded, and the portion between the first slit position and the second slit position Is mixed with the raw material resin of the extruder as a recovered raw material to prevent mixing of the part including the primary foaming part, and the part with the flow mark is used as the recovered raw material to improve the raw material efficiency and Large sheet It is possible to obtain the out molded products.
[0024]
  Of the present inventionExtrusion equipmentIsPushBetween the cylinder of the machine and the sheet dieAn adapter is interposed,The width from the foremost position of the screw head of the extruder to the nearest adapter channel side wall surface during extrusion in the connected state is 0.1 to 5 of the width between the opposing adapter channel side wall surfaces. %, And can be moved back and forth in the axial direction of the screw with respect to the cylinder of the extruder,StartBefore moving the cylinder of the extruderEach with an adapterIncreased to molding temperature in a separated stateMade possibleAfter heating up,BothTo be connected and start upDoneTherefore, in the state before the temperature rise where the cylinder and the adapter of the extruder are separated, the cylinder is compared with the length of the cooled screw head.-Even if is greatly contracted, the tip of the screw head does not come into contact with the side wall surface of the adapter channel, so that they can be prevented from being damaged. It can be assembled so that the distance between the tip of the screw head and the side wall surface of the adapter flow path becomes small.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a horizontal cross-sectional view illustrating an example of an extrusion molding process together with an example of an extrusion molding apparatus used in the method for producing a sheet-like extrusion molded product of the present invention, and FIGS. 2 (a) to 2 (g). FIG. 3 is a vertical cross-sectional view taken along lines a to g in FIG. 1, FIG. 3 is a horizontal cross-sectional view showing a state before activation of the extrusion molding apparatus shown in FIG. 1, and FIG. 4 is a sheet-like extrusion according to the present invention. It is a top view explaining the slit condition of the both-sides edge part of the sheet-like extrusion molding in an example of the manufacturing method of a molded article.
[0026]
As shown in FIG. 1, the extrusion molding apparatus 1 shows a state during extrusion molding, and the base end of an adapter 12 of an example of the present invention is connected to the tip of a cylinder 11 of the extruder. The proximal end of the sheet die 13 is connected to the distal end.
[0027]
The inner wall surface at the base end portion and the center portion of the adapter 12 is an inclined surface 121 that gradually decreases in width toward the distal end, and the inner wall surface at the distal end portion is a concentric tubular surface 122 in a reduced width state.
On the outer peripheral surface of the base end portion of the adapter 12, a flange portion 123 for fastening with the tip end of the cylinder 11 of the extruder is provided along the circumferential direction. On the outer peripheral surface of the distal end portion of the adapter 12, a flange portion 124 for fastening with the base end of the sheet die 13 is provided along the circumferential direction.
[0028]
The sheet die 13 has an inner peripheral surface at the base end portion that is the same width as the inner wall surface of the tip end portion of the adapter 12 (see FIG. 2E), and an inclined surface in which the inner wall surface at the center portion suddenly widens toward the tip end. [Refer to FIG. 2 (f)], and the inner wall surface of the tip is a parallel surface with the same width in an expanded state (see FIG. 2 (g)).
[0029]
As shown in FIG. 2A, screw main body portions 141 and 141 of screws 14 and 14 are installed in the cylinder 11 of the extruder. As shown in FIG. 2 (b), screw heads 142, 142 of the screws 14, 14 project from the adapter 12.
As shown in FIG. 2 (c), the width X from the foremost position of the screw heads 142, 142 to the closest adapter channel side wall surface is 0.1 of the width R between the opposing adapter channel side wall surfaces. It is made to be 5%.
[0030]
As shown in FIG. 3, the adapter 12 can be moved back and forth with respect to the cylinder 11 of the extruder, and rises to the molding temperature in a state separated from the cylinder 11 of the extruder before the extrusion molding apparatus 1 is started. Then, after the temperature rise is finished, it is brought close to the cylinder 11 of the extruder, and the flange portion 123 is connected to the tip of the cylinder 11 of the extruder by a bolt (not shown) so that the extrusion molding is performed. The apparatus can be activated.
As a result, when the temperature of the screw head 142 in the separated state is increased, the tip of the screw head 142 and the adapter flow in the connected state after the temperature increase is completed even if the amount of movement of the screw head cooled is smaller than the expansion of the cylinder. It can assemble | attach so that the distance with a road side wall surface may become small.
[0031]
Next, an example of the molding process in the method for producing a sheet-like extruded product of the present invention using the above-described extrusion molding apparatus 1 will be described with reference to the same FIGS.
First, in the first step, as shown in FIG. 3, the temperature rises to the molding temperature in a state where the cylinder 11 and the adapter 12 of the extruder are separated before the extrusion molding apparatus 1 is started.
[0032]
Next, in the second step, after the temperature rise is finished, as shown in FIG. 1, the cylinder 11 of the extruder and the adapter 12 are connected to each other, the extrusion molding apparatus 1 is started, and during extrusion molding. The positions of the flow marks F, F generated by the resin staying in the spaces K, K near the tip of the screw head are set to the both side edges of the sheet-like extruded product 2 ′ formed by the sheet die 13. Extrusion molding is performed (see FIGS. 2D to 2G).
[0033]
At this time, as shown in FIG. 4, the first slit positions B1 and B2 for separating the waste portions are formed at both side edges of the sheet-like extruded body 2 ′ after passing through a cooling roll (not shown). The widths A1-B1 and A2-B2 from both side edges A1 and A2 of the body 2 'are at positions where the width is 0.1 to 5% with respect to the total width L of the sheet-like extruded body 2'.
At the same time, the second slit positions C1 and C2, which are inside the first slit positions B1 and B2 and cut off the portion used as the recovered raw material, have a width A1 from both side edges A1 and A2 of the sheet-like extruded product 2 ′. -C1 and A2-C2 are positioned at 1 to 15% with respect to the total width L of the sheet-like extruded product 2 ', and the portion composed of A1-B1 and A2-B2 is discarded, and the first slit Portions B1-C1 and B2-C2 between the position and the second slit position are mixed with the raw material resin of the extruder as a recovered raw material.
As a result, a sheet-like extruded product 2 having an effective width of C1-C2 is obtained.
[0034]
In the last step, after the extrusion molding is completed, the resin discharge is stopped, and as shown in FIG. 3 again, the cylinder 11 and the adapter 12 of the extruder are separated and cooled.
At this time, the cylinder contracts greatly compared to the amount of movement of the screw head 142 that is cooled, but since the cylinder 11 and the adapter 12 of the extruder are separated, the tip of the screw head is connected to the side wall surface of the adapter channel. There is no contact and it is prevented from damaging them.
[0035]
FIG. 5 is a horizontal cross-sectional view for explaining another example of the adapter of the present invention, and FIG. 6 is a vertical cross-sectional view showing a state before activation of an extrusion molding apparatus provided with the adapter.
As shown in FIG. 5, the adapter 12 'has a channel insert 124' mounted on the inner periphery of the base end portion and the central portion, and the inner wall surface of the channel insert 124 'faces the tip. It is the same as that described with reference to FIGS. 1 to 3 except that the inclined surface gradually decreases.
[0036]
As shown in FIG. 6, the adapter 12 ′ is movable back and forth with respect to the cylinder 11 of the extruder, and is molded at a molding temperature in a state separated from the cylinder 11 of the extruder before the extrusion molding apparatus 1 is started. After the temperature rise is completed, it is brought close to the cylinder 11 of the extruder and is connected so that the flange 123 ′ is fastened to the tip of the cylinder 11 of the extruder with a bolt 15 (FIG. 5). Thus, the extrusion molding apparatus 1 can be activated.
As a result, even when the amount of movement of the screw head 142 that is cooled compared to the expansion of the cylinder 11 is small at the time of temperature rise in the separated state, It can assemble | attach so that the distance with an adapter flow-path side wall surface may become small.
[0037]
(Example)
Hereinafter, the present invention will be described with reference to examples.
Example 1
(1) Preparation of modified polyolefin resin
As a modification screw extruder, a TEX-44 type (manufactured by Nippon Steel Works Co., Ltd.) co-rotating twin screw extruder was used. This extruder is equipped with a self-wiping twin screw, and its substantial L / D is 31.5 and D is 47 mm. The cylinder barrel is composed of first to ninth cylinders from the upstream side to the downstream side of the extruder, and a breaker and a connecting flange to a foaming agent kneading extruder, which will be described later, are installed at the extrusion tip.
[0038]
The operating conditions were as follows.

[0039]
First, a polyolefin resin and a dioxime compound were quantitatively supplied from separate hoppers to the modification screw extruder having the above configuration, and both were melted and mixed to obtain a modified resin.
As the polyolefin resin, a polypropylene random copolymer (“EG8” manufactured by Mitsubishi Chemical Corporation) was used, and the supply amount was 50 kg / h.
As the modifying monomer, p-quinone dioxime (“Barunok GM-P” manufactured by Ouchi Shinsei Chemical Co., Ltd.) was used, and its supply amount was 0.8 parts by weight with respect to 100 parts by weight of the polyolefin resin.
The modified resin obtained by melt blending the polyolefin resin and the modifying monomer was discharged through a connecting flange to the fifth cylinder of a foaming agent kneading extruder described later.
[0040]
(2) Preparation of foamable resin composition
A TEX-65 type (manufactured by Nippon Steel Works) co-rotating twin screw extruder was used as the foaming agent kneading screw extruder. This extruder is equipped with a self-wiping twin screw, and its L / D is 45.5 and D is 69 mm. The cylinder is composed of first to thirteenth cylinders from the upstream side to the downstream side of the extruder, and the sheet die is a T die having a width of 1600 mm and a lip interval of 0.6 mm.
The temperature setting categories were as follows.
The first cylinder is always cooled
First zone: 2-5 cylinders
Second zone: 6th to 8th cylinders
3rd zone: 9th to 13th cylinders
Zone 4: Die and adapter section
[0041]
In this foaming agent kneading screw extruder, a flange for supplying the modified resin from the modifying screw extruder is connected to the fifth cylinder, and a side feeder is provided in the eighth cylinder for supplying the blowing agent. A vacuum vent is installed in the eleventh cylinder to recover the volatile matter.
The operating conditions were as follows.

[0042]
The first cylinder of the foaming agent kneading screw extruder is made of polyolefin resin as a blending resin, and the above modified resin is connected to the fifth cylinder of the blowing agent kneading screw extruder through a connecting flange from the modifying screw extruder. Supplied to. As a polyolefin-based resin for blending, homotype polypropylene (“MA3” manufactured by Mitsubishi Chemical Corporation) was used, and the supply amount was 50 kg / h. Moreover, the foaming agent was supplied to the extruder from the side feeder and dispersed. As the foaming agent, azodicarbonamide (ADCA) was used, and the supply amount was 4 kg / h.
[0043]
(3) Molding of sheet-like extruded products
The foamable resin composition thus obtained by kneading the modified resin, the blend resin and the foaming agent is extruded from the T-die through the extruder and adapter of the extrusion molding apparatus, cooled through three cooling rolls, and the width L = A sheet-like extrudate 2 ′ having a thickness of 1540 mm and a thickness of 0.7 mm was obtained.
[0044]
At this time, as shown in FIG. 4, the first slit positions B1 and B2 for separating the waste portions at both side edges of the sheet-like extruded product 2 ′ after passing through the cooling roll are the positions shown in Table 1. At the same time, the second slit positions C1 and C2, which are inside the first slit positions B1 and B2 and cut off the portion used as the recovered raw material, have a width A1 from both side edges A1 and A2 of the sheet-like extruded product 2 ′. -C1, A2-C2 became the position shown in Table 1 with respect to the full width L of the sheet-like extruded product 2 ', and a sheet-like extruded product 2 having a predetermined width (C1-C2) was obtained.
The discarded part including the primary foaming part H is discarded, and the recovered raw material is pulverized after the parts B1-C1 and B2-C2 between the first slit position and the second slit position not including the primary foaming part and including the flow mark F. As a foaming agent, a fixed amount was supplied to the first cylinder of a kneading screw extruder.
[0045]
As the screw head and the adapter, those having dimensions shown in Table 1 were used.
Measurement of the distance from the tip of the screw head to the adjacent adapter channel side wall surface was performed as follows.
The screw body portion, screw head, and cylinder of the extruder were heated to the molding temperature, and a flow path insert 124 was attached to the cylinder 11 of the extruder using bolts 15 (for nesting fixation) as shown in FIG. At this time, the relative position between the forefront of the screw head 142 and the channel nesting 124 was adjusted by the spacer 143. And the inside was looked into from the exit side of the flow path nest 124, and the distance X was measured.
[0046]
In accordance with the method described with reference to FIGS. 1 to 3, before the extrusion molding apparatus 1 is activated, the cylinder 11 of the extruder is separated from the cylinder 11 of the extruder and the adapter 12 ′, and after the rise to the molding temperature is completed. 11 and the adapter 12 'are connected to each other, the extrusion molding apparatus 1 is started, and the flow mark F generated by the resin staying in the spaces K and K near the tip of the screw head during extrusion molding. Extrusion molding was performed so that the position of F was located on both side edges of the extrusion molded body 2 ′ shaped by the sheet die 13.
[0047]
After completion of the extrusion, the resin discharge was stopped, the cylinder 11 and the adapter 12 'of the extruder were separated, and the cooling was performed.
[0048]
(4) Preparation and foaming of composite sheet
Non-woven fabric made of polyethylene terephthalate (manufactured by Toyobo Co., Ltd., “Spunbond Ecule 6301A”), basis weight 30 g / m², Tensile strength: 1.6 kg / cm in length and 1.2 kg / cm in width) were heat-sealed to obtain a polyolefin resin foamable composite sheet.
The obtained polyolefin resin foamable composite sheet was thermally foamed at 220 ° C. for about 5 minutes in a continuous foaming machine having a heating zone, to obtain a composite foam having a magnification of about 10 cc / g.
[0049]
(5) Performance evaluation
About the obtained composite foam, the performance evaluation of the following item was performed.
-Effective width measurement as a product:
About the composite foam, the product effective width excluding the flow mark portion was measured.
・ Measurement of primary foam width as a product:
About the composite sheet before foaming, the primary foaming width | variety (one side) which generate | occur | produced in the outermost part was measured.
[0050]
Example 2
In the molding (3) of the sheet-like extruded product, performance evaluation was performed on the obtained composite foam in the same manner as in Example 1 except that the screw head and the adapter having the dimensional relationships shown in Table 1 were used. went. The results are shown in Table 1.
[0051]
Comparative example
In the molding (3) of the sheet-like extruded product, performance evaluation was performed on the obtained composite foam in the same manner as in Example 1 except that the screw head and the adapter having the dimensional relationships shown in Table 1 were used. went. The results are shown in Table 1.
[0052]
[Table 1]

[0053]
As is clear from Table 1, in the case of the example of the present invention, the width of the primary foamed portion was slightly larger than in the case of the comparative example, but a large effective product width could be secured.
[0054]
【The invention's effect】
Since the manufacturing method of the sheet-like extrusion molded product of the present invention has the above-described configuration, there is no risk of damaging the tip of the screw head and the side wall surface of the adapter flow path, and the position of the flow mark is adjusted to that of the sheet-like extrusion molding. Extrusion can be performed so as to be on both side edges.
[0055]
  Of the present inventionExtrusion equipmentSince it is set as said structure, it can assemble | attach so that the distance of the front-end | tip part of a screw head and an adapter flow-path side wall surface may become small at the time of shaping | molding.
[Brief description of the drawings]
FIG. 1 shows an example of a method for producing a sheet-like extruded product of the present invention.Of the present inventionIt is a horizontal sectional view explaining with an example of an extrusion molding device.
FIGS. 2A to 2G are longitudinal sectional views taken along lines a to g in FIG. 1, respectively.
FIG. 3 is a horizontal sectional view showing a state before the start of the extrusion molding apparatus shown in FIG. 1;
FIG. 4 is a plan view for explaining a slit state at both side edges of a sheet-like extruded product in an example of a method for producing a sheet-like extruded product of the present invention.
FIG. 5 shows the present invention.Used forIt is sectional drawing which shows another example of an adapter.
6 is a longitudinal sectional view showing a state before the start of the extrusion molding apparatus including the adapter shown in FIG.
FIG. 7 is a horizontal cross section for explaining an example of a method for producing a sheet-like extruded product using a conventional extrusion molding apparatus.FigureIt is.
[Explanation of symbols]
  1 Extrusion equipment
  11 cylinders
  12 Adapter
  13 Sheet die
  14 screw
  142 screw head

Claims (3)

A method of manufacturing an extrusion-molded product using an extrusion molding apparatus provided with an adapter between a cylinder of an extruder and a sheet die, wherein the cylinder of the extruder and the adapter are separated before starting the extrusion molding apparatus. In the process of raising to the molding temperature at the end, and connecting the two after the temperature rise , the width from the most advanced position of the screw head of the extruder to the nearest adapter channel side wall is between the opposite adapter channel side walls. The extrusion molding apparatus is started in a state of 0.1 to 5% of the width, and the extrusion process is performed by shaping with the sheet die, and after the extrusion molding is finished, the resin discharge is stopped. And a step of separating the cylinder of the extruder and the adapter and cooling them.   The first slit position at which the waste portion is cut off at both side edge portions of the sheet-like extruded product is 0.1 to the total width of the sheet-like extrusion product. The second slit position that is inside the first slit position and cuts off the portion to be used as the recovered raw material has a width from both side edges of the sheet-like extrudate. It becomes the position which becomes 1 to 15% with respect to the full width of the shaped extruded body, the discard part is discarded, and the part between the first slit position and the second slit position is used as the recovered raw material for the raw material of the extruder It mixes with resin, The manufacturing method of the sheet-like extrusion-molded article of Claim 1 characterized by the above-mentioned. Is the adapter interposed between the cylinder and the sheet die press extruder, the extrusion being molded by them connected state, the width up to the adapter flow path side wall nearest the screw head cutting edge position of the extruder, as being such that 0.1 to 5% of the width between the opposed adapter flow path wall, have been freely advance and retreat in the axial direction of the screw with respect to the cylinder of the extruder, the prior start a cylinder and adapter of the extruder is permitted to rise to a molding temperature in a state separated respectively, after completion of heating, and characterized in that to form a state of connecting the two, it has been made to be able to perform the activation Extrusion equipment to do.

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