JPH03138126A - Injection molding process for even thin wall hollow molded product - Google Patents
Injection molding process for even thin wall hollow molded productInfo
- Publication number
- JPH03138126A JPH03138126A JP27488989A JP27488989A JPH03138126A JP H03138126 A JPH03138126 A JP H03138126A JP 27488989 A JP27488989 A JP 27488989A JP 27488989 A JP27488989 A JP 27488989A JP H03138126 A JPH03138126 A JP H03138126A
- Authority
- JP
- Japan
- Prior art keywords
- molded product
- cavity
- resin
- mold cavity
- mold
- 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.)
- Pending
Links
- 238000001746 injection moulding Methods 0.000 title claims abstract description 10
- 229920005989 resin Polymers 0.000 claims abstract description 46
- 239000011347 resin Substances 0.000 claims abstract description 46
- 238000000034 method Methods 0.000 claims abstract description 22
- 229920005992 thermoplastic resin Polymers 0.000 claims abstract description 10
- 238000007599 discharging Methods 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 26
- 238000002347 injection Methods 0.000 description 10
- 239000007924 injection Substances 0.000 description 10
- 238000000465 moulding Methods 0.000 description 8
- 229930182556 Polyacetal Natural products 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 4
- 229920006324 polyoxymethylene Polymers 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- 239000004677 Nylon Substances 0.000 description 1
- 239000004793 Polystyrene Substances 0.000 description 1
- 229920000122 acrylonitrile butadiene styrene Polymers 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 238000000071 blow moulding Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 229910052731 fluorine Inorganic materials 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 239000011796 hollow space material Substances 0.000 description 1
- 239000000113 methacrylic resin Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229920001778 nylon Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920002492 poly(sulfone) Polymers 0.000 description 1
- 229920001230 polyarylate Polymers 0.000 description 1
- 229920005668 polycarbonate resin Polymers 0.000 description 1
- 239000004431 polycarbonate resin Substances 0.000 description 1
- 229920001225 polyester resin Polymers 0.000 description 1
- 239000004645 polyester resin Substances 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 229920001955 polyphenylene ether Polymers 0.000 description 1
- 229920002223 polystyrene Polymers 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000012779 reinforcing material Substances 0.000 description 1
- 229920006395 saturated elastomer Polymers 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
- B29C45/00—Injection moulding, i.e. forcing the required volume of moulding material through a nozzle into a closed mould; Apparatus therefor
- B29C45/17—Component parts, details or accessories; Auxiliary operations
- B29C45/1703—Introducing an auxiliary fluid into the mould
- B29C45/1704—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles
- B29C45/1711—Introducing an auxiliary fluid into the mould the fluid being introduced into the interior of the injected material which is still in a molten state, e.g. for producing hollow articles and removing excess material from the mould cavity by the introduced fluid, e.g. to an overflow cavity
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Mechanical Engineering (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
- Blow-Moulding Or Thermoforming Of Plastics Or The Like (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、熱可塑性樹脂の均一薄肉中空成形品を製造す
るための射出成形方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an injection molding method for producing uniformly thin-walled hollow molded articles of thermoplastic resin.
熱可塑性樹脂の中空成形品を製造する従来技術の最も一
般的な方法は、押出しパリソンを用いるプロー成形法か
、゛あるいは２個以上の型物を成形し、これらを接着に
よって一体化する方法である。これらの方法では、比較
的肉厚の均一な中空成形品が得られるものの、成形品の
形状や大きさに制約があるし、成形工程が複雑で、成形
費用も高くつ（という欠点は免れ難いものであった。The most common conventional methods for manufacturing thermoplastic resin blow molded products are the blow molding method using an extruded parison, or the method of molding two or more molds and integrating them by adhesive. be. Although these methods can produce hollow molded products with relatively uniform wall thickness, there are restrictions on the shape and size of the molded product, the molding process is complicated, and the molding cost is high. It was something.
これらの欠点を解消するとともに、射出成形法によって
中空成形品を製造する方法も多く提案されており、例え
ば、特公昭５７−１４９６８号公報には、型キャビティ
を満すに不十分な量の溶融樹脂を型キャビティに注入し
た後、引続き同じ入口よりガス体を注入して中空型物を
製造する方法が開示されている。しかし、この方法では
、型キャビティ内（ζ射出、注入された溶融樹脂は、金
型表面の温度分布および型キャビティ内へ注入される過
程における型キャビティ内での溶融樹脂の堆積状態によ
り複雑な温度分布を持ち、そのために、ガス体を注入さ
れた時点でキャビティ内の樹脂は複雑な粘度分布を持つ
ことになる。従って、このような状態にある型キャビテ
ィ内の溶融樹脂にガス体を注入すると、樹脂及びガス体
の流れは複雑な経路をたどり、キャビティ内の樹脂が均
一にキャビテイ壁面に押しつけられることは望むべくも
なく、薄肉中空品はおろか、均一な肉厚の中空品を得る
ことは事実上極めて困難である。すなわち、均一薄肉中
空品を得るべく型キャビティ内に不十分な皿の溶融樹脂
を注入したのち、次いで加圧ガス体を注入した場合、型
キャビティ内の樹脂は型キャビティの奥に押し込まれ、
ゲート付近に留まる樹脂量は少なく、従って、ゲート付
近は極薄肉で奥部は厚肉となる不均一な肉厚中空品が形
成されるのが通例である。In addition to solving these drawbacks, many methods have been proposed for producing hollow molded products by injection molding. A method is disclosed for manufacturing a hollow mold by injecting a resin into a mold cavity and subsequently injecting a gas through the same inlet. However, with this method, the temperature of the injected molten resin inside the mold cavity (ζ injection) is complicated due to the temperature distribution on the mold surface and the deposition state of the molten resin inside the mold cavity during the process of injection into the mold cavity. Therefore, the resin in the cavity will have a complicated viscosity distribution at the time the gas is injected.Therefore, if the gas is injected into the molten resin in the mold cavity in this state, , the flow of resin and gas follows a complicated path, and it is impossible to expect that the resin in the cavity will be pressed uniformly against the cavity wall, making it impossible to obtain hollow products with uniform wall thickness, let alone thin-walled hollow products. In fact, it is extremely difficult to do so.In other words, if an insufficient amount of molten resin is injected into the mold cavity to obtain a uniformly thin-walled hollow product, and then a pressurized gas is injected, the resin in the mold cavity will not reach the mold cavity. pushed deep inside,
The amount of resin remaining near the gate is small, and therefore a hollow product with uneven wall thickness is usually formed, with an extremely thin wall near the gate and a thick wall at the inner part.
この不都合を解消するべく、奥部が厚肉とならないよう
に溶融樹脂の注入量を減らす工夫も考えられるが、この
場合１こは、加圧ガス体を注入した際、キャビテイ壁全
面１こ均一に樹脂を配分することが困難となり、局部的
に超薄肉部分が形成され、その部分が破れてガスが吹き
出し、所望の中空成形品が得られない危険が高（なる。In order to solve this problem, it is possible to reduce the amount of molten resin injected so that the inner part does not become thick, but in this case, when the pressurized gas is injected, the entire cavity wall is uniformly It becomes difficult to allocate the resin to the parts, and there is a high risk that ultra-thin parts will be formed locally, which will rupture and gas will blow out, making it impossible to obtain the desired hollow molded product.
そこで、注入ガス体の圧力を加減する方法も考えられる
が、ガス体の圧力が低い場合には型キャビティ内の樹脂
を十分に型キャビテイ壁全面にまわし切れず、不均一な
肉厚中空品が得られたり、外観の極めて不良な成形品が
得られたり、時には所望の形状が保持されない成形品が
得られる原因にもなりかねない。Therefore, one possibility is to adjust the pressure of the injected gas, but if the pressure of the gas is low, the resin in the mold cavity cannot be sufficiently distributed over the entire mold cavity wall, resulting in a hollow product with uneven wall thickness. This may result in a molded product having an extremely poor appearance, or in some cases, a molded product that does not retain its desired shape.
（発明が解決しようとする問題点とそれを解決する手段
〕
本発明の目的は、中空部が偏在することなく、且つ肉厚
が均一な薄肉中空成形品を射出成形１こよって製造する
方法を提供することにある。(Problems to be Solved by the Invention and Means for Solving the Problems) An object of the present invention is to provide a method for manufacturing thin-walled hollow molded products with uniform wall thickness by injection molding 1 without unevenly distributed hollow parts. It is about providing.
この目的を達成するために、本発明は、成形品型キャビ
ティと該成形品型キャビティに連通した補助キャビティ
を備えた金型を用い、前記成形品型キャビティ内に溶融
した熱可塑性樹脂を注入し、次いで、該溶融樹脂中に加
圧ガス体を注入し、加圧ガス体による保圧下に成形品型
キャビティ内の溶融樹脂の一部を前記補助キャビティ内
へ排出させることによって、所望の均一薄肉の中空成形
品を射出成形法によって製造する方法を提供する。To achieve this objective, the present invention uses a mold having a mold cavity and an auxiliary cavity communicating with the mold cavity, and injects a molten thermoplastic resin into the mold cavity. Next, a pressurized gas body is injected into the molten resin, and a part of the molten resin in the molded mold cavity is discharged into the auxiliary cavity under the pressure maintained by the pressurized gas body, thereby forming a desired uniformly thin wall. Provided is a method for manufacturing a hollow molded product using an injection molding method.
本発明の方法においては、成形品型キャビティに射出、
注入された溶融樹脂は、次いで注入される加圧ガス体の
作用をうけてキャビテイ壁面に向って流れ、所望の成形
品の形状を形成するが、さらに、加圧ガス体によって溶
融樹脂の一部が補助キャビティへ押し出される間に、ガ
ス体が与える圧力によって溶融樹脂は型キャビティの壁
面に押しつけられるばかりでなく、壁面に沿うように流
れ、それ１ζよって、所望の形状が形成されるとともに
、均一な肉厚が形成され、均一薄肉の中空成形品が極め
て容易に形成される。In the method of the present invention, injection into the mold cavity,
The injected molten resin then flows toward the cavity wall under the action of the injected pressurized gas, forming the desired shape of the molded product. While the molten resin is being pushed out into the auxiliary cavity, the pressure exerted by the gas not only forces the molten resin against the wall of the mold cavity, but also causes it to flow along the wall, thereby forming the desired shape and making it uniform. A hollow molded product with a uniformly thin wall can be formed extremely easily.
かかる本発明の方法は、型キャビティ内の樹脂をガス体
でキャビテイ壁面に押し付けるという従来の技術思想と
は異なり、キャビティの中心部１こ存在する中空成形品
には本来不必要な溶融樹脂を、ガス体の圧力によって補
助キャビティへ排出し、それによ′って中空部を成形品
全域に形成するとともに、肉厚を均一１ζ形成させると
いう合理的な技術思想にもとづくものである。The method of the present invention differs from the conventional technical idea of pressing the resin inside the mold cavity against the cavity wall surface using a gaseous body, and instead of using the method of the present invention, molten resin, which is originally unnecessary for the hollow molded product that exists in the center of the cavity, is This is based on the rational technical concept of discharging the gas into the auxiliary cavity by the pressure of the gas, thereby forming a hollow part over the entire molded product, and forming a wall with a uniform thickness of 1ζ.
本発明の方法によれば、型キャビティの外周部の既に路
却された樹脂による断熱効果によって溶融状態を長く保
っている中心部の樹脂をガス体の圧力で強制的に補助キ
・ヤビティヘ排出するので、成形品の冷却時間が短くな
って成形サイクルの大幅な短縮が実現でき、成形コスト
の低減を可能とする。さらには、成形品内部にほぼ全域
にわたって中空部が形成されるためガス体による保圧が
均一に維持され、それによって、外観が良好で、反りや
ひけもない成形精度にすぐれた中空成形品が容易に得ら
れる。According to the method of the present invention, the resin in the center, which has been kept in a molten state for a long time due to the heat insulating effect of the resin that has already been discharged on the outer periphery of the mold cavity, is forcibly discharged into the auxiliary cavity by the pressure of the gas body. Therefore, the cooling time of the molded product is shortened, the molding cycle can be significantly shortened, and molding costs can be reduced. Furthermore, since a hollow space is formed inside the molded product over almost the entire area, the pressure maintained by the gas is maintained uniformly, resulting in a hollow molded product that has a good appearance and has excellent molding accuracy without warping or sinking. easily obtained.
本発明の方法を実施するための製品型キャビティと補助
キャビティとの容積比率の選定に当っては、特に制約は
ないが、例えば、加圧ガス体の圧力にも関連するが、そ
の比率は中空成形品の肉厚を決定する要因にもなる。通
常、製品型キャビティと１個の補助キャビティの容積比
率は１００対０．５から１００対９５の範囲から適宜選
定されればよい。使用する補助キャビティの数は、目的
とする成形品の形状や使用する樹脂の流れ特性や成形品
の肉厚など種々の要因を考慮の上で決定され、２個以上
の複数個の補助キャビティが用いられる態様があること
は勿論である。There are no particular restrictions on the selection of the volume ratio of the product mold cavity and the auxiliary cavity for carrying out the method of the invention, but for example, the ratio is also related to the pressure of the pressurized gas body; It is also a factor in determining the wall thickness of the molded product. Usually, the volume ratio of the product mold cavity to one auxiliary cavity may be appropriately selected from the range of 100:0.5 to 100:95. The number of auxiliary cavities to be used is determined by considering various factors such as the shape of the intended molded product, the flow characteristics of the resin used, and the wall thickness of the molded product. Of course, there are other ways in which it can be used.
成形品型キャビティに補助キャビティを連通させる位置
は、通常、ゲートから相対的に遠い位置で選ばれるが、
これに限定されるものではなく、成形品の形状や補助キ
ャビティの数に応じて適宜設計されればよい。The position where the auxiliary cavity communicates with the mold cavity is usually selected at a position relatively far from the gate.
It is not limited to this, and may be designed as appropriate depending on the shape of the molded product and the number of auxiliary cavities.
成形品型キャビティ内に射出、注入される溶融した熱可
塑性樹脂の量は、型キャビティを十分に充す量でありて
も、型キャビティを充すに不十分な量であってもよく、
型キャビティと補助キャビティとの容積比率や目的成形
品に要求される肉厚等を考慮の上、適宜定められる。The amount of molten thermoplastic resin injected into the mold cavity of the molded article may be an amount sufficient to fill the mold cavity or an amount insufficient to fill the mold cavity;
It is determined as appropriate in consideration of the volume ratio of the mold cavity and the auxiliary cavity, the wall thickness required for the target molded product, etc.
本発明の方法を実施するに当って、成形品型キャビティ
内の溶融樹脂中に加圧ガス体を注入する注入口の態様は
、゛ゲート部位で見て樹脂とガスが同じ位置で型キャビ
ティに注入される態様であっても、ゲート部位とは異な
る位置で直接型キャビティに注入される態様であっても
よい。ここで、ゲート部位で見て樹脂とガスが同じ位置
というのは、射出成形機のノズルの先端において同じ口
より樹脂とガスとが注入される態様はもとより、ガスの
注入口がスプル一部またはランナ一部に設けられた態様
をも包含することは勿論である。In carrying out the method of the present invention, the mode of the injection port for injecting the pressurized gas into the molten resin in the mold cavity of the molded product is as follows: It may be injected, or it may be injected directly into the mold cavity at a location different from the gate site. Here, the resin and gas are in the same position when viewed from the gate area, not only because the resin and gas are injected from the same port at the tip of the nozzle of the injection molding machine, but also because the gas injection port is part of the sprue or Of course, it also includes a mode provided in a part of the runner.
本発明の方法に用いられるガス体は、常温、常圧におい
て気体である物質であり、使用する熱可塑性樹脂に対し
て不活性であればいずれの物質であってよいが、安全性
および経済性より、通常窒素ガスが好適に用いられる。The gas used in the method of the present invention is a substance that is a gas at normal temperature and normal pressure, and may be any substance as long as it is inert to the thermoplastic resin used, but it is safe and economical. Therefore, nitrogen gas is usually preferably used.
本発明の方法を適用できる熱可塑性樹脂としては、特に
制約はなく、ポリオレフィン、ポリスチレン、ＡＢＳ樹
１１’ｌ、ＡＳ樹脂、ｐｖｃ樹ｇ、メタアクリル樹脂、
含ふっそ樹脂等で例示されるいわゆる汎用プラスチック
スはもとより、ナイロン、飽和ポリエステル樹脂、ポリ
カーボネート樹脂、ボリアリレート樹脂、ポリアセター
ル樹脂、ポリスルホン、変性ポリフェニレンエーテル樹
脂等で例示されるエンジニアリングプラスチックスにも
適用できる。所望に応じて、本発明の方法は、これらの
樹脂に繊維強化材を配合した素材にも適用できることは
勿論である。The thermoplastic resin to which the method of the present invention can be applied is not particularly limited, and includes polyolefin, polystyrene, ABS resin, AS resin, PVC resin, methacrylic resin,
It can be applied not only to so-called general-purpose plastics such as fluorine-containing resins, but also to engineering plastics such as nylon, saturated polyester resins, polycarbonate resins, polyarylate resins, polyacetal resins, polysulfones, modified polyphenylene ether resins, etc. . It goes without saying that the method of the present invention can also be applied to materials prepared by blending these resins with fiber reinforcing materials, if desired.
本発明の方法を実施するに当たって、射出成形時の溶融
樹脂の温度、射出圧力、および射出速度；ガス体の注入
の時期、量、圧力および速度；あるいは金型の冷却時間
等積々の条件は、使用する樹脂素材の種類、金型の形状
等に見合わせて適宜選定、制御されねばならず、一義的
に定め得ない。In carrying out the method of the present invention, various conditions such as the temperature, injection pressure, and injection speed of the molten resin during injection molding; the timing, amount, pressure, and speed of gas injection; or the cooling time of the mold, etc. , must be appropriately selected and controlled depending on the type of resin material used, the shape of the mold, etc., and cannot be determined unambiguously.
実施例
成形品型キャビティと補助キャビティとの容積比率が１
００対３８になるように設計された金型（補助キャビテ
ィの数は１個）を用い、熱可塑性樹脂としてポリアセタ
ール樹脂（三菱瓦斯化学株式会社製、財品名「ユピター
ル Ｆ２Ｏ−０３Ｊ）を用い、溶融したポリアセタール
樹脂が型キャビティを不十分に満す実施態様で、以下の
とと（中空成形品を成形した。Example The volume ratio of the mold cavity and the auxiliary cavity is 1
Using a mold designed to have a ratio of 00 to 38 (the number of auxiliary cavities is 1), polyacetal resin (manufactured by Mitsubishi Gas Chemical Co., Ltd., product name "Iupital F2O-03J") was used as the thermoplastic resin, and melted. In an embodiment in which the polyacetal resin insufficiently filled the mold cavity, the following blow molded articles were molded.
射出成形機内で樹脂温度１９０℃に溶融、可塑化された
ポリアセタール樹脂 １６．Ｆｌを射出圧力 ５００Ｖ
４／−にて前記金型内に注入し、次いで、０．５秒後に
樹脂と同じ注入口より圧力２０Ｋｔ／ｆｆｌの窒素ガス
を注入した。Polyacetal resin melted and plasticized at a resin temperature of 190°C in an injection molding machine 16. Fl injection pressure 500V
The resin was injected into the mold at a pressure of 4/-, and then, 0.5 seconds later, nitrogen gas was injected at a pressure of 20 Kt/ffl from the same injection port as the resin.
６０秒後に成形品を取り出した。The molded article was taken out after 60 seconds.
得られた成形品の重量は５．１９であり、肉厚は２．０
〜２．５罰の範囲の極めて均一な薄肉厚を有していた。The weight of the obtained molded product was 5.19, and the wall thickness was 2.0.
It had a very uniform thin wall thickness ranging from ~2.5 mm.
成形品の外観は極めて美麗で、光沢があった。The appearance of the molded product was extremely beautiful and shiny.
比較例
補助キャビティのない金型を用いて実施例と同じ操作を
繰り返して中空成形品を成形した。Comparative Example A hollow molded product was molded by repeating the same operations as in the example using a mold without an auxiliary cavity.
得られた成形品の重量は１３．８．９であって、肉厚は
０．５〜７ＴｎＮの極めて不均一な肉厚の中空成形品で
あり、外観も不良で光沢は見られなかった。The weight of the obtained molded product was 13.8.9 mm, and it was a hollow molded product with an extremely nonuniform wall thickness of 0.5 to 7 TnN, and its appearance was poor and no gloss was observed.
実施例及び比較例の結果から明らかなごとく、補助キャ
ビティを持つ成形品型キャビティを備えた金型を用いて
熱可塑性樹脂の中空成形品を成形する本発明の方法によ
って、肉厚が均一で外観も美麗な薄肉中空成形品が射出
、成形され得ることが判る。As is clear from the results of Examples and Comparative Examples, the method of the present invention for molding a thermoplastic resin hollow molded product using a mold equipped with a molding cavity having an auxiliary cavity has a uniform wall thickness and a uniform appearance. It can be seen that beautiful thin-walled hollow molded products can be injected and molded.
Claims (1)
補助キャビティとを備えた金型を用い、前記成形品型キ
ャビティに溶融した熱可塑性樹脂を注入し、次いで、該
溶融樹脂中に加圧ガス体を注入し、加圧ガス体による保
圧下に成形品型キャビティ内の溶融樹脂の一部を前記補
助キャビティ内へ排出せしめることからなる均一薄肉中
空成形品の射出成形方法。Using a mold having a mold cavity and an auxiliary cavity communicating with the mold cavity, a molten thermoplastic resin is injected into the mold cavity, and then a pressurized gas is introduced into the molten resin. A method for injection molding a uniformly thin-walled hollow molded product, which comprises injecting molten resin into the auxiliary cavity and discharging a part of the molten resin in the molded mold cavity into the auxiliary cavity while maintaining pressure with a pressurized gas body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27488989A JPH03138126A (en) | 1989-10-24 | 1989-10-24 | Injection molding process for even thin wall hollow molded product |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27488989A JPH03138126A (en) | 1989-10-24 | 1989-10-24 | Injection molding process for even thin wall hollow molded product |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03138126A true JPH03138126A (en) | 1991-06-12 |
Family
ID=17547945
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27488989A Pending JPH03138126A (en) | 1989-10-24 | 1989-10-24 | Injection molding process for even thin wall hollow molded product |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03138126A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5124360A (en) * | 1989-03-08 | 1992-06-23 | The University Of Virginia Alumni Patents Foundation | Dietary supplement for insulin-resistant diabetics |
| WO2003006227A1 (en) * | 2001-07-10 | 2003-01-23 | Gas Injection, Ltd. | Expulsion process by gas injection moulding |
-
1989
- 1989-10-24 JP JP27488989A patent/JPH03138126A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5124360A (en) * | 1989-03-08 | 1992-06-23 | The University Of Virginia Alumni Patents Foundation | Dietary supplement for insulin-resistant diabetics |
| WO2003006227A1 (en) * | 2001-07-10 | 2003-01-23 | Gas Injection, Ltd. | Expulsion process by gas injection moulding |
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