JPH0221926B2 - - Google Patents
Info
- Publication number
- JPH0221926B2 JPH0221926B2 JP60196746A JP19674685A JPH0221926B2 JP H0221926 B2 JPH0221926 B2 JP H0221926B2 JP 60196746 A JP60196746 A JP 60196746A JP 19674685 A JP19674685 A JP 19674685A JP H0221926 B2 JPH0221926 B2 JP H0221926B2
- Authority
- JP
- Japan
- Prior art keywords
- barrel
- kneading shaft
- screw
- resin
- shaft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000004898 kneading Methods 0.000 claims description 50
- 229920005989 resin Polymers 0.000 claims description 36
- 239000011347 resin Substances 0.000 claims description 36
- 239000006260 foam Substances 0.000 claims description 10
- 238000002347 injection Methods 0.000 claims description 8
- 239000007924 injection Substances 0.000 claims description 8
- 239000004604 Blowing Agent Substances 0.000 claims description 6
- 230000002093 peripheral effect Effects 0.000 claims description 6
- 229920005992 thermoplastic resin Polymers 0.000 claims description 4
- 238000011144 upstream manufacturing Methods 0.000 claims description 2
- 239000004088 foaming agent Substances 0.000 description 17
- 238000005187 foaming Methods 0.000 description 7
- 239000003507 refrigerant Substances 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 239000002994 raw material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 239000003063 flame retardant Substances 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000002028 premature Effects 0.000 description 2
- DEIGXXQKDWULML-UHFFFAOYSA-N 1,2,5,6,9,10-hexabromocyclododecane Chemical compound BrC1CCC(Br)C(Br)CCC(Br)C(Br)CCC1Br DEIGXXQKDWULML-UHFFFAOYSA-N 0.000 description 1
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 1
- 239000004338 Dichlorodifluoromethane Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- PXBRQCKWGAHEHS-UHFFFAOYSA-N dichlorodifluoromethane Chemical compound FC(F)(Cl)Cl PXBRQCKWGAHEHS-UHFFFAOYSA-N 0.000 description 1
- 235000019404 dichlorodifluoromethane Nutrition 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- JBKVHLHDHHXQEQ-UHFFFAOYSA-N epsilon-caprolactam Chemical compound O=C1CCCCCN1 JBKVHLHDHHXQEQ-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000012768 molten material Substances 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 239000000454 talc Substances 0.000 description 1
- 229910052623 talc Inorganic materials 0.000 description 1
- -1 that is Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
- B29C48/86—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the nozzle zone
- B29C48/87—Cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/375—Plasticisers, homogenisers or feeders comprising two or more stages
- B29C48/385—Plasticisers, homogenisers or feeders comprising two or more stages using two or more serially arranged screws in separate barrels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/50—Details of extruders
- B29C48/505—Screws
- B29C48/53—Screws having a varying channel depth, e.g. varying the diameter of the longitudinal screw trunk
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/50—Details of extruders
- B29C48/505—Screws
- B29C48/565—Screws having projections other than the thread, e.g. pins
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
- B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
- B29C48/83—Heating or cooling the cylinders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
- B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
- B29C48/83—Heating or cooling the cylinders
- B29C48/832—Heating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
- B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
- B29C48/83—Heating or cooling the cylinders
- B29C48/834—Cooling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/25—Component parts, details or accessories; Auxiliary operations
- B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
- B29C48/375—Plasticisers, homogenisers or feeders comprising two or more stages
- B29C48/387—Plasticisers, homogenisers or feeders comprising two or more stages using a screw extruder and a gear pump
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
- Molding Of Porous Articles (AREA)
Description
（産業上の利用分野）
本発明は、熱可塑性樹脂発泡体の製造装置に関
するものである。
（従来の技術）
合成樹脂を均一に混合するためのものとして、
特開昭57−87344号公報に記載された押出混合機
がある。これは、中空円筒状の固定子と、この固
定子内に回転できるよう支持された円柱状の回転
子とを有し、固定子及び回転子の対向面にそれぞ
れ孤立したキヤビテイを設け、固定子のキヤビテ
イを回転子のキヤビテイの間に跨つて位置させた
ものであつて、通常の押出機に付設され、固定子
は、その押出機のバレルに連結され、回転子は、
押出機のスクリユ先端に連結される。
上記スクリユの回転により押出機混合機内に樹
脂が押し出されると、その樹脂は、回転子及び固
定子のキヤビテイによつて剪断され、効率よく混
練される。
（発明が解決しようとする問題点）
上記従来構成によれば、樹脂を効率よく混練す
ることができるが、その樹脂に発泡剤を添加して
樹脂発泡体を製造する場合には問題がある。
すなわち、発泡剤の適正な発泡温度範囲は比較
的狭まく、その範囲より低い温度では不十分な発
泡しか生じず、その範囲より高い温度では早期発
泡が生じてしまう。そこで、通常、バレルの外周
にヒータを設けて、温度コントロールを行つてい
るが、前述した押出混合機では、樹脂を効率よく
混練することができる反面、発熱しやすく、発泡
剤の適正な発泡温度範囲を越えるおそれがある。
特に、常温で液状の易揮発性発泡剤を用いた場合
には、その悪影響が顕著に生じる。
本発明者は、樹脂及び発泡剤を予備的に混練す
れば、回転子及び固定子の長さを短くしても、充
分、樹脂を混練することができ、他方、発熱を低
く押さえることができることを発見した。本発明
はかかる発見に基づくものである。
（問題を解決するための手段）
上記問題を解決するため、本発明の熱可塑性樹
脂発泡体の製造装置は、バレル内にスクリユを片
持式で回転可能に支持し、バレルのスクリユ先端
がわを樹脂の排出口とした押出機において、バレ
ル内のスクリユ先端に予備混練軸と主混練軸とを
この順序で同芯状に連設し、予備混練軸に多数の
突起を有し、主混練軸の外周面をバレル内周面に
接近させ、主混練軸の外周面及びこれに対向する
バレル内周面に互いに孤立した多数のキヤビテイ
を形成し、バレル内周面のキヤビテイを主混練軸
のキヤビテイの間に跨つて位置させ、バレルの予
備混練軸の上流側に発泡剤圧入口を設け、主混練
軸の長さをスクリユ直径の２ないし８倍とし、予
備混練軸の長さをスクリユ直径の１ないし７倍と
したものである。
上記構成において、バレル内に供給された樹脂
は、スクリユの回転によつて押し出されて行き、
発泡剤圧入口から発泡剤が添加され、予備混練軸
の突起により予備的に混練された後、主混練軸と
バレルとの間の隙間内に押し込まれ、主混練軸及
びバレルのキヤビテイによつて効率よく混練さ
れ、冷却機で冷却された後、口金から排出されて
発泡し、樹脂発泡体が製造される。
（実施例）
以下、本発明の一実施例を図に基づいて説明す
る。１は押出機、２は冷却機であつて、押出機１
と平行に配列されるとともに、その押出機１とは
芯がずれている。３は押出機１の排出口４と冷却
機２の注入口５とをつなぐ樹脂供給管である。
上記押出機１は、次のものから構成されてい
る。６はバレル、７はバレル６内に回転自在に挿
入された片持式のスクリユ、８，９はスクリユ７
の先端に同芯状に連設された予備混練軸と主混練
軸、１０は予備混練軸８に多数植設された突起、
１１，１２は主混練軸９の外周面及びこれに対向
するバレル６の内周面に形成された多数の孤立し
た半球状の窪み形状のキヤビテイであつて、バレ
ル６のキヤビテイ１２を主混練軸のキヤビテイ１
１の間に跨つて位置させてある。上記主混練軸９
の外周面はバレル６の内周面に接近している。１
３はバレル６の予備混練軸８とスクリユ７との境
界に対向する箇所に設けられた発泡剤圧入口、１
４はバレル６のスクリユ支持がわの端に形成され
た樹脂投入口、１５はバレル６の外周面に設けら
れたヒータである。
前記冷却機２は次のものから構成されている。
１７は外筒であつて、螺旋状の冷媒通路１８を有
する。１９は外筒１７内に回転自在に挿入された
片持式の主軸、２０は外筒１７の先端に設けられ
た排出口２１付き口金、２２は主軸１９内に形成
された冷却空間内に冷媒を供給するための冷媒供
給パイプである。主軸１９は、外筒１７に軸受２
３を介して回転自在に支持された基端大径部１９
Ａと、中央小径部１９Ｂと、先端大径部１９Ｃと
から構成され、中央小径部１９Ｂの注入口５に対
向する箇所から若干下流に寄つた箇所に環状突出
部１９Ｄを設けてある。２４は中央小径部１９Ｂ
の環状突出部１９Ｄよりも下流側に多数突設され
たハードル形の混練棒である。
前記主混練軸９の長さは、スクリユ直径の２な
いし８倍（好ましくは４ないし６倍）としてあ
る。２倍以下では、混練が不足し、８倍以上では
発熱が大きくなり過ぎる。
予備混練軸８の長さは、スクリユ直径の１ない
し７倍（好ましくは２ないし５倍）としてある。
１倍以下では、予備混練が不足し、７倍以上で
は、それ以上、混練効果が向上しない。
予備混練軸８の部分の樹脂通過断面積を、スク
リユ７の先端部分の樹脂通過断面積よりも大きく
してある（好ましくは1.5ないし３倍）。その逆で
あると、予備混練軸８上に供給される樹脂の量が
過剰となり、充分な予備混練を行うことができな
い。また、予備混練軸８上に設けられる突起１０
としては円柱状のピン、スクリユースライトを切
欠いた形状、ダルメージ形状のものがある。
以下、上記構成の作用を説明する。スクリユ７
及び主軸１９をそれぞれ矢印Ａ，Ｂ方向へ回転さ
せ、原料、すなわち樹脂を投入口１４からバレル
６内に供給する。すると、樹脂はスクリユ７によ
つて矢印Ｃ方向へ送られ、その間にヒータ１５に
より加熱され、溶融される。溶融された樹脂に発
泡剤圧入口１３から発泡剤が圧入され、その発泡
剤と樹脂とが突起１０によつて予備的に混合させ
られる。次に、その発泡剤含有樹脂は主混練軸９
とバレル６との間の隙間内に押し込まれ、キヤビ
テイ１１，１２によつて混練され、発泡剤が樹脂
内に均等に分散させられる。その混練の原理を第
３図ａないしｈに示す模式図により線条を使つて
説明する。まず、同図ａの左側のキヤビテイ１２
の底から出てきた線条は、そのキヤビテイ１２の
内周面に沿つて延び、同図ｂに示すごとく、線条
の先端は、矢印Ａ方向へ回転する主混練軸９のキ
ヤビテイ１１間の縁イに引つ張られて方向を変
え、同図ｃに示す状態になり、同図ｄに示すごと
く、縁ロにより線条の先端が折り曲げられ、同図
ｅに示すごとく、縁ロとバレル６とで線条の先端
が切断され、同図ｆに示すごとく、縁ハにより線
条の先端が折り曲げられ、同図ｇに示すごとく、
縁ハとバレル６とで線条の先端が切断され、同図
ｈに示すごとく、縁ニにより線条の先端が折り曲
げられる。以後、同じ動作がくり返えされて、線
条の先端が次々と切断され、その切断された線条
部分はキヤビテイ１２内に溜つて行く。従つて、
この原理により、樹脂は上記線条のように薄く延
ばされて、小さく切り刻まれ、発泡剤が樹脂内に
均等に分散させられるものである。次に、発泡剤
が均等に分散させられた樹脂は、供給管３内を通
つて冷却機２の外筒１７内に入り、環状突出部１
９Ｄを越えて矢印Ｄ方向へ圧送され、矢印Ｂ方向
へ回転するハードル形の混練棒２４により混練さ
れ、また同時に適度に冷却された後、先端大径部
１９Ｃと外筒１７との間の隙間を通り、排出口２
１から押出されて発泡するに至る。
次に、具体的実施例の１を説明する。バレル６
の内径を50mmとし、スクリユ７の直径を50mmと
し、予備混練軸８の長さを250mmとし、主混練軸
９の長さを250mmとし、主混練軸９とバレル６と
の間の隙間を0.4mmとし、主混練軸９及びバレル
６にそれぞれ円周方向に６個、軸方向に７列のキ
ヤビテイ１１，１２を設け、キヤビテイ１１の直
径を24.5mmとし、その深さを８mmとし、キヤビテ
イ１２の直径を23mmとし、その深さを9.5mmとし、
キヤビテイ１１及び１２間の間隔を何れも22mmと
し、スクリユ７の回転数を106rpmとし、冷却機
２内を通る溶融物の温度を123℃に調整し、口金
２０の排出口２１の幅を100mm、その高さを１mm
とした。
かかる構成において、ポリスチレン〔旭化成株
式会社製スタイロン679（Ｍ＝17）〕を基材樹脂と
し、その基材樹脂100重量部に対し、気泡調整剤
としてタルク0.3重量部、難燃剤としてヘキサブ
ロモシクロドデカン2.0重量部を均一に混合した
ものを原料として押出機１に供給し、その押出機
１を１時間あたり55Kgの割合で原料が押出される
ように作動させた。また発泡剤圧入口１３から発
泡剤としてジクロロジフルオロメタンを基材樹脂
100重量部に対して12.5重量部圧入した。
その結果、口金２０に付設されたサイザーを通
じて幅約250mm、厚さ約25mm、密度40Kg／m3の板
状発泡体を得ることができた（別表を参照）。
なお、別表の比較例は、主混練軸９を外し、バ
レル６のキヤビテイ１２を無くした場合を示して
いる。
(Industrial Application Field) The present invention relates to a thermoplastic resin foam manufacturing apparatus. (Conventional technology) For uniformly mixing synthetic resins,
There is an extrusion mixer described in JP-A-57-87344. This has a hollow cylindrical stator and a cylindrical rotor rotatably supported within the stator. It is attached to a normal extruder, and the stator is connected to the barrel of the extruder, and the rotor is connected to the barrel of the extruder.
Connected to the screw tip of the extruder. When the resin is extruded into the extruder mixer by the rotation of the screw, the resin is sheared by the cavities of the rotor and stator and is efficiently kneaded. (Problems to be Solved by the Invention) According to the above-described conventional structure, resin can be efficiently kneaded, but there is a problem when producing a resin foam by adding a blowing agent to the resin. That is, the proper foaming temperature range of the foaming agent is relatively narrow, and temperatures lower than that range will only result in insufficient foaming, while temperatures higher than that range will result in premature foaming. Therefore, a heater is usually installed around the outer periphery of the barrel to control the temperature. However, while the extrusion mixer described above can efficiently knead the resin, it easily generates heat, and the appropriate foaming temperature of the blowing agent cannot be adjusted. There is a risk of exceeding the range.
In particular, when a readily volatile foaming agent that is liquid at room temperature is used, its adverse effects are significant. The present inventor has discovered that if the resin and foaming agent are pre-kneaded, the resin can be sufficiently kneaded even if the length of the rotor and stator is shortened, and on the other hand, the heat generation can be kept low. discovered. The present invention is based on this discovery. (Means for Solving the Problems) In order to solve the above problems, the thermoplastic resin foam manufacturing apparatus of the present invention rotatably supports a screw in a barrel in a cantilevered manner, and the tip of the screw in the barrel In an extruder with a resin discharge port, a pre-kneading shaft and a main kneading shaft are connected concentrically in this order at the tip of the screw in the barrel, and the pre-kneading shaft has many protrusions, and the main kneading shaft The outer circumferential surface of the shaft is brought close to the inner circumferential surface of the barrel, and a number of isolated cavities are formed on the outer circumferential surface of the main kneading shaft and the inner circumferential surface of the barrel opposite thereto. The blowing agent injection port is provided on the upstream side of the pre-kneading shaft of the barrel, and the length of the main kneading shaft is 2 to 8 times the screw diameter. It is 1 to 7 times that of In the above configuration, the resin supplied into the barrel is pushed out by the rotation of the screw,
The foaming agent is added through the foaming agent injection port, and after being preliminarily kneaded by the protrusion of the pre-kneading shaft, it is pushed into the gap between the main kneading shaft and the barrel, and is then mixed by the cavity of the main kneading shaft and the barrel. After being efficiently kneaded and cooled in a cooler, the resin is discharged from the die and foamed to produce a resin foam. (Example) Hereinafter, an example of the present invention will be described based on the drawings. 1 is an extruder, 2 is a cooler, and the extruder 1
The extruder 1 is arranged in parallel with the extruder 1, and is off-center from the extruder 1. 3 is a resin supply pipe connecting the outlet 4 of the extruder 1 and the inlet 5 of the cooler 2. The extruder 1 is comprised of the following: 6 is a barrel, 7 is a cantilever screw rotatably inserted into the barrel 6, and 8 and 9 are screws 7.
A pre-kneading shaft and a main kneading shaft are concentrically connected at the tip of the shaft, 10 is a large number of protrusions implanted on the pre-kneading shaft 8,
Reference numerals 11 and 12 denote a number of isolated hemispherical depression-shaped cavities formed on the outer circumferential surface of the main kneading shaft 9 and the inner circumferential surface of the barrel 6 opposite thereto. cavity 1
It is located across 1. The main kneading shaft 9
The outer peripheral surface of the barrel 6 is close to the inner peripheral surface of the barrel 6. 1
Reference numeral 3 denotes a blowing agent injection port provided at a location opposite to the boundary between the pre-kneading shaft 8 and the screw 7 of the barrel 6;
4 is a resin inlet formed at the end of the screw supporting side of the barrel 6, and 15 is a heater provided on the outer peripheral surface of the barrel 6. The cooler 2 is composed of the following:
Reference numeral 17 is an outer cylinder having a spiral refrigerant passage 18. 19 is a cantilevered main shaft rotatably inserted into the outer cylinder 17, 20 is a base with a discharge port 21 provided at the tip of the outer cylinder 17, and 22 is a refrigerant in the cooling space formed in the main shaft 19. This is a refrigerant supply pipe for supplying refrigerant. The main shaft 19 has a bearing 2 on the outer cylinder 17.
3, the proximal large diameter portion 19 is rotatably supported through
A, a central small diameter portion 19B, and a tip large diameter portion 19C, and an annular protrusion 19D is provided at a location slightly downstream from a portion of the central small diameter portion 19B facing the injection port 5. 24 is the central small diameter portion 19B
These are hurdle-shaped kneading rods that are protruded in large numbers on the downstream side of the annular protrusion 19D. The length of the main kneading shaft 9 is set to 2 to 8 times (preferably 4 to 6 times) the diameter of the screw. If it is less than 2 times, kneading will be insufficient, and if it is more than 8 times, heat generation will be too large. The length of the pre-kneading shaft 8 is set to 1 to 7 times (preferably 2 to 5 times) the diameter of the screw.
If it is less than 1 times, preliminary kneading will be insufficient, and if it is more than 7 times, the kneading effect will not be improved any further. The resin passage cross-sectional area of the pre-kneading shaft 8 is made larger than the resin passage cross-sectional area of the tip of the screw 7 (preferably 1.5 to 3 times). If it is the other way around, the amount of resin supplied onto the pre-kneading shaft 8 will be excessive, making it impossible to perform sufficient pre-kneading. Further, a protrusion 10 provided on the pre-kneading shaft 8
Examples include cylindrical pins, screw lights with notches, and dalmage shapes. The operation of the above configuration will be explained below. Skrillyu 7
Then, the main shaft 19 is rotated in the directions of arrows A and B, respectively, and raw material, that is, resin, is supplied into the barrel 6 from the input port 14. Then, the resin is sent in the direction of arrow C by the screw 7, during which time it is heated and melted by the heater 15. A foaming agent is press-injected into the molten resin from a foaming agent injection port 13, and the foaming agent and resin are preliminarily mixed by a protrusion 10. Next, the foaming agent-containing resin is mixed into the main kneading shaft 9
The foaming agent is pushed into the gap between the resin and the barrel 6, and is kneaded by the cavities 11 and 12, so that the foaming agent is evenly dispersed in the resin. The principle of kneading will be explained using wires using the schematic diagrams shown in FIGS. 3a to 3h. First, the cavity 12 on the left side of Figure a.
The filaments that come out from the bottom extend along the inner circumferential surface of the cavity 12, and as shown in FIG. It is pulled by the edge A and changes its direction, reaching the state shown in Figure c, and the tip of the filament is bent by the Edge Lo, as shown in Figure d, and the Edge Lo and barrel form as shown in Figure E. 6, the tip of the filament is cut off, and the tip of the filament is bent by the edge C, as shown in figure f, and as shown in figure g,
The tip of the filament is cut by the edge C and the barrel 6, and the tip of the filament is bent by the edge D, as shown in FIG. Thereafter, the same operation is repeated, the tips of the filaments are cut one after another, and the cut filament portions accumulate in the cavity 12. Therefore,
Based on this principle, the resin is stretched thin like the above-mentioned filaments and cut into small pieces, and the foaming agent is evenly dispersed within the resin. Next, the resin with the foaming agent evenly dispersed passes through the supply pipe 3 and enters the outer cylinder 17 of the cooler 2, and enters the annular protrusion 1.
9D in the direction of arrow D, kneaded by the hurdle-shaped kneading rod 24 rotating in the direction of arrow B, and cooled appropriately at the same time, the gap between the large diameter portion 19C at the tip and the outer cylinder 17 is through the outlet 2
It is extruded from 1 and foams. Next, a first concrete example will be described. Barrel 6
The inner diameter of the screw 7 is 50 mm, the length of the pre-kneading shaft 8 is 250 mm, the length of the main kneading shaft 9 is 250 mm, and the gap between the main kneading shaft 9 and the barrel 6 is 0.4 mm. mm, the main kneading shaft 9 and the barrel 6 are provided with 6 cavities 11, 12 in the circumferential direction and 7 rows in the axial direction, the diameter of the cavity 11 is 24.5 mm, the depth is 8 mm, and the cavities 12 The diameter is 23mm, the depth is 9.5mm,
The distance between the cavities 11 and 12 was set to 22 mm, the rotation speed of the screw 7 was set to 106 rpm, the temperature of the molten material passing through the cooler 2 was adjusted to 123°C, and the width of the outlet 21 of the mouthpiece 20 was set to 100 mm. Its height is 1mm
And so. In this configuration, polystyrene [Stylon 679 (M = 17) manufactured by Asahi Kasei Corporation] is used as the base resin, and 0.3 parts by weight of talc as a bubble regulator and hexabromocyclododecane as a flame retardant are added to 100 parts by weight of the base resin. A uniform mixture of 2.0 parts by weight was supplied as a raw material to an extruder 1, and the extruder 1 was operated to extrude the raw material at a rate of 55 kg per hour. In addition, dichlorodifluoromethane is added to the base resin as a foaming agent from the foaming agent injection port 13.
12.5 parts by weight was press-fitted to 100 parts by weight. As a result, a plate-shaped foam having a width of about 250 mm, a thickness of about 25 mm, and a density of 40 Kg/m 3 was obtained through the sizer attached to the nozzle 20 (see the attached table). Note that the comparative example in the attached table shows the case where the main kneading shaft 9 was removed and the cavity 12 of the barrel 6 was eliminated.
【表】
別表から明らかなように、本発明の具体的実施
例によれば、均一発泡の発泡体を得ることができ
た。
（発明の効果）
以上述べたごとく、本発明によれば、スクリユ
により押出されてきた樹脂及び発泡剤を予備混練
軸の突起により予備的に混練するようにしたか
ら、主混練軸の長さをスクリユ直径の２ないし８
倍の範囲に限定し、従来より短かくすることがで
き、主混練軸及びバレルのキヤビテイによる発熱
を低く押さえることができるものである。従つ
て、バレル内を通る樹脂の温度を適正な発泡温度
範囲内に保持することができ、例え、易揮発性の
発泡剤を用いたとしても、早期発泡のおそれがな
く、所定どおりに発泡した発泡体を得ることがで
きる。また、樹脂の分子量低下や、難燃剤などの
添加剤の分解といつた問題が生じることもない。[Table] As is clear from the attached table, according to the specific examples of the present invention, uniformly foamed foams could be obtained. (Effects of the Invention) As described above, according to the present invention, the resin and foaming agent extruded by the screw are preliminarily kneaded by the protrusions of the pre-kneading shaft, so that the length of the main kneading shaft can be reduced. Screw diameter 2 to 8
It can be made shorter than the conventional one, and the heat generated by the main kneading shaft and barrel cavity can be suppressed to a low level. Therefore, the temperature of the resin passing through the barrel can be maintained within the appropriate foaming temperature range, and even if an easily volatile foaming agent is used, there is no risk of premature foaming and foaming will occur as specified. A foam can be obtained. Moreover, problems such as a decrease in the molecular weight of the resin and decomposition of additives such as flame retardants do not occur.
図は、本発明の一実施例を示し、第１図は縦断
面図、第２図は第１図の−矢視図、第３図ａ
〜ｈはキヤビテイによる混練の原理を示す概略説
明図である。
各図において、１は押出機、２は冷却機、６は
バレル、７はスクリユ、８は予備混練軸、９は主
混練軸、１０は突起、１１，１２はキヤビテイ、
１３は発泡剤圧入口である。
The drawings show an embodiment of the present invention, in which Fig. 1 is a longitudinal sectional view, Fig. 2 is a view taken along the - arrow in Fig. 1, and Fig. 3 a
-h are schematic explanatory diagrams showing the principle of kneading using cavities. In each figure, 1 is an extruder, 2 is a cooler, 6 is a barrel, 7 is a screw, 8 is a preliminary kneading shaft, 9 is a main kneading shaft, 10 is a protrusion, 11 and 12 are cavities,
13 is a blowing agent injection port.
Claims (1)
持し、バレルのスクリユ先端がわを樹脂の排出口
とした押出機において、バレル内のスクリユ先端
に予備混練軸と主混練軸とをこの順序で同芯状に
連設し、予備混練軸に多数の突起を有し、主混練
軸の外周面をバレル内周面に接近させ、主混練軸
の外周面及びこれに対向するバレル内周面に互い
に孤立した多数のキヤビテイを形成し、バレル内
周面のキヤビテイを主混練軸のキヤビテイの間に
跨つて位置させ、バレルの予備混練軸の上流側に
発泡剤圧入口を設け、主混練軸の長さをスクリユ
直径の２ないし８倍とし、予備混練軸の長さをス
クリユ直径の１ないし７倍としたことを特徴とす
る、熱可塑性樹脂発泡体の製造装置。 ２ 予備混練軸部分の樹脂通過断面積をスクリユ
先端部分の樹脂通過断面積よりも大きくしたこと
を特徴とする、特許請求の範囲第１項記載の熱可
塑性樹脂発泡体の製造装置。[Scope of Claims] 1. In an extruder in which a screw is rotatably supported in a cantilever type in a barrel, and the tip of the screw in the barrel is used as a resin discharge port, a pre-kneading shaft and a main shaft are attached to the tip of the screw in the barrel. The kneading shafts are arranged concentrically in this order, the pre-kneading shaft has a large number of protrusions, the outer peripheral surface of the main kneading shaft is brought close to the inner peripheral surface of the barrel, and the outer peripheral surface of the main kneading shaft and this A large number of isolated cavities are formed on the inner circumferential surfaces of opposing barrels, and the cavities on the inner circumferential surfaces of the barrels are positioned astride between the cavities of the main kneading shaft, and the blowing agent injection inlet is located upstream of the pre-kneading shaft of the barrel. 1. An apparatus for producing a thermoplastic resin foam, characterized in that the length of the main kneading shaft is 2 to 8 times the screw diameter, and the length of the pre-kneading shaft is 1 to 7 times the screw diameter. 2. The apparatus for producing a thermoplastic resin foam according to claim 1, characterized in that the cross-sectional area of the resin passing through the pre-kneading shaft portion is larger than the cross-sectional area through which the resin passes through the screw tip portion.
Priority Applications (10)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60196746A JPS6256114A (en) | 1985-09-05 | 1985-09-05 | Manufacturing device for thermoplastic resin foam |
| CA000514389A CA1255866A (en) | 1985-07-24 | 1986-07-22 | Method and apparatus for production of foamed thermoplastic material |
| AT0199286A AT394518B (en) | 1985-07-24 | 1986-07-23 | DEVICE FOR PRODUCING FOAMED THERMOPLASTIC PLASTIC |
| DE3624909A DE3624909C2 (en) | 1985-07-24 | 1986-07-23 | Method and device for producing a foamed thermoplastic composition |
| KR1019860005964A KR900003735B1 (en) | 1985-07-24 | 1986-07-23 | Method and apparatus for production of foames thermoplastic material |
| PT83040A PT83040B (en) | 1985-07-24 | 1986-07-23 | METHOD AND APPARATUS FOR THE PRODUCTION OF FOAM THERMOPLASTIC MATERIAL |
| ES8601339A ES2001581A6 (en) | 1985-07-24 | 1986-07-24 | Method and apparatus for production of foamed thermoplastics material |
| CN86105207A CN1007717B (en) | 1985-07-24 | 1986-07-24 | Method and apparatus for production of foamed thermoplastic material |
| GB8618082A GB2179886B (en) | 1985-07-24 | 1986-07-24 | Method and apparatus for production of foamed thermoplastics material |
| FR868610767A FR2585282B1 (en) | 1985-07-24 | 1986-07-24 | METHOD AND APPARATUS FOR MANUFACTURING A FOAM OF A THERMOPLASTIC MATERIAL BY MIXING THE MATERIAL WITH A POROGENIC AGENT AND CONTINUOUS EXTRUSION |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60196746A JPS6256114A (en) | 1985-09-05 | 1985-09-05 | Manufacturing device for thermoplastic resin foam |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6256114A JPS6256114A (en) | 1987-03-11 |
| JPH0221926B2 true JPH0221926B2 (en) | 1990-05-16 |
Family
ID=16362915
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60196746A Granted JPS6256114A (en) | 1985-07-24 | 1985-09-05 | Manufacturing device for thermoplastic resin foam |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6256114A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2862979T3 (en) * | 2018-05-02 | 2021-10-08 | Buss Ag | Mixing and kneading machine and its use |
-
1985
- 1985-09-05 JP JP60196746A patent/JPS6256114A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6256114A (en) | 1987-03-11 |
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