JP2000084954A - Production of polyamide resin molding - Google Patents
Production of polyamide resin moldingInfo
- Publication number
- JP2000084954A JP2000084954A JP26072198A JP26072198A JP2000084954A JP 2000084954 A JP2000084954 A JP 2000084954A JP 26072198 A JP26072198 A JP 26072198A JP 26072198 A JP26072198 A JP 26072198A JP 2000084954 A JP2000084954 A JP 2000084954A
- Authority
- JP
- Japan
- Prior art keywords
- polyamide resin
- mold
- molded article
- reinforcing plate
- producing
- 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.)
- Granted
Links
Landscapes
- Moulds For Moulding Plastics Or The Like (AREA)
- Casting Or Compression Moulding Of Plastics Or The Like (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明はポリアミド樹脂成形
体の製造方法に係り、詳しくは比較的高負荷および高温
下で使用されるギア、ローラ、車輪等を用途とする補強
材を含んだポリアミド樹脂成形体の脱型を短時間に行
い、しかも重合不足やヒケ発生を少なくしたポリアミド
樹脂成形体の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polyamide resin molded article, and more particularly, to a polyamide resin containing a reinforcing material used for gears, rollers, wheels, etc. used under relatively high loads and high temperatures. The present invention relates to a method for producing a polyamide resin molded article in which demolding of the molded article is performed in a short time, and in which insufficient polymerization and sink marks are reduced.
【0002】[0002]
【従来の技術】ポリアミド樹脂成形体は、軽量化や無給
油運転や静音化等を目的として金属製ギア、ローラ、車
輪などの代替品としてしばしば用いられている。しか
し、極めて高負荷の条件で用いたり、通常の条件下でも
長期に使用することによって限界を越え、ポリアミド樹
脂部と軸との境界に存在するキー溝部から破壊すること
があった。2. Description of the Related Art Polyamide molded articles are often used as substitutes for metal gears, rollers, wheels, etc. for the purpose of weight reduction, oil-free operation, noise reduction, and the like. However, when used under extremely high load conditions or when used under normal conditions for a long period of time, the limit may be exceeded, and breakage may occur from the key groove existing at the boundary between the polyamide resin portion and the shaft.
【0003】このためポリアミド樹脂の軽量であるとと
もにメンテナンスフリーで長期にわたって使用できると
いう特長を生かしながらボス部のみは金属のものを用い
る構造のものが提案されている。このポリアミド樹脂部
に金属ボス部を固定する方法として、冷間圧入による方
法や加熱膨張させたポリアミド樹脂部を金属ボス部に圧
入する方法(焼嵌法)、ビスによって機械的に固定する
方法などが一般に行われていた。また、ポリアミド樹脂
部をローレット加工を施した金属に冷間圧入し、金属を
加熱してポリアミド樹脂部と金属とを融着一体化する方
法が、特許第2622813号に開示されている。For this reason, a structure has been proposed in which only the boss portion is made of metal while taking advantage of the features that the polyamide resin is lightweight and maintenance-free and can be used for a long period of time. As a method of fixing the metal boss portion to the polyamide resin portion, a method of cold press-fitting, a method of press-fitting the heated and expanded polyamide resin portion into the metal boss portion (shrink fitting method), a method of mechanically fixing with a screw, etc. Was commonly done. Japanese Patent No. 2622813 discloses a method in which a polyamide resin portion is cold-pressed into knurled metal, and the metal is heated to fuse and integrate the polyamide resin portion and the metal.
【0004】[0004]
【発明が解決しようとする課題】しかしながら、これら
の方法は夫々問題点を有している。まず冷間圧入法と焼
嵌法では、金属ボス部との間の固定力が弱く、短期間の
うちに金属ボス部とポリアミド樹脂部との間にズレが生
じてしまうことがあった。However, each of these methods has its own problems. First, in the cold press-fitting method and the shrink-fitting method, the fixing force between the metal boss portion and the polyamide resin portion is sometimes short in a short time.
【0005】また、高温下におけるポリアミド樹脂の熱
膨張、長時間の使用による応力緩和によってポリアミド
樹脂部の抱き付き力は低下し、固定力はさらに弱くなる
かビスなどによる固定ではビス穴への応力集中によって
ポリアミド樹脂部が破壊しやすくなる。また製品形状に
よってはビスの取付ができないことも往々にしてある。
これを避けるために製造時の圧入代、焼嵌代を大きめに
取ると樹脂側に過大な歪みが生じ、所定の大きさに加工
する際や部品として使用している時に、その歪みが原因
で破壊してしまうこともあった。Further, the holding force of the polyamide resin portion is reduced by thermal expansion of the polyamide resin at a high temperature and relaxation of stress due to long use, and the fixing force is further reduced. Concentration makes the polyamide resin part easily broken. In some cases, screws cannot be attached depending on the product shape.
To avoid this, if the press-fitting margin and shrink-fitting margin at the time of manufacture are set to be large, excessive distortion will occur on the resin side, and when processing to a predetermined size or when using as a part, the distortion will cause Sometimes it was destroyed.
【0006】更に、ポリアミド樹脂部を金属に冷間圧入
し、金属を加熱して両者を融着一体化する方法において
は、加工工数が多くて製品が高価になる問題があった。Further, the method of cold-pressing a polyamide resin portion into a metal, heating the metal, and fusing and integrating the both has a problem that the number of processing steps is large and the product is expensive.
【0007】このため、低コストの方法として、金型内
にローレット加工を施した金属補強材を支持台に設置し
た後、重合性ラクタム液を注型して成形したが、重合過
程で発生する収縮により重合体と金属補強材がずれるこ
とによってこの間に隙間が発生し、またヒケが発生して
良品がとれない問題が発生した。更に、重合が完了した
後に成形体を脱型する場合、金型を反転していたが、成
形体が支持台に抱き付くことがあって、成形体の脱型に
時間を要していた。For this reason, as a low-cost method, a metal reinforcing material subjected to knurling is placed in a mold and then molded by pouring a polymerizable lactam liquid, but this occurs during the polymerization process. A gap is generated between the polymer and the metal reinforcing material due to shrinkage due to the shrinkage, and a sink occurs to cause a problem that a good product cannot be obtained. Further, when removing the molded article after the completion of the polymerization, the mold was turned upside down, but the molded article was sometimes hugged by the support, and it took time to remove the molded article.
【0008】本発明は、このような諸問題を解決し、ポ
リアミド樹脂の利点を生かした軽量で無給油にて長期に
渡って使用でき、ポリアミド樹脂成形体の脱型を容易
に、かつ重合不足やヒケ発生を少なくし、そしてポリア
ミド樹脂と補強材との結合力を維持したポリアミド樹脂
成形体の製造方法の提供を目的とする。The present invention solves these problems, and makes use of the advantages of polyamide resins, is lightweight, can be used for a long time without lubrication, facilitates demolding of polyamide resin molded articles, and causes insufficient polymerization. It is an object of the present invention to provide a method for producing a polyamide resin molded article in which the occurrence of shrinkage and sink marks is reduced and the bonding strength between the polyamide resin and the reinforcing material is maintained.
【0009】[0009]
【課題を解決するための手段】即ち、本願請求項1記載
の発明は、補強板の周囲にポリアミド樹脂を結合し一体
化したポリアミド樹脂成形体の製造方法において、少な
くとも1つ以上の窪み状注型部を配した成形部の外周囲
に連続した内溝部を設け、更にその外側に液溜用の外溝
部を設けた温度調節可能な金型を用意し、該金型の各注
型部に支持台を金型底面に対して移動自在に設置して補
強板を上記支持台に固定した後、実質上無水のω−ラク
タムに少なくともアニオン重合触媒とアニオン重合開始
剤とを加えた重合性ラクタム液を注型部から溢れさせつ
つ内溝部まで充満し、続いて重合性ラクタム液の液面に
空気を介在させないように遮蔽材をシールした後、上蓋
を設置して重合し、重合が完了した後に成形体を脱型す
るポリアミド樹脂成形体の製造方法にある。That is, the invention according to claim 1 of the present application relates to a method for manufacturing a polyamide resin molded body in which a polyamide resin is bonded to and integrated with a reinforcing plate. A continuously adjustable inner groove is provided around the outer periphery of the molding section where the mold section is arranged, and a temperature-adjustable mold having an outer groove section for the liquid reservoir is further provided on the outside thereof. A polymerizable lactam obtained by adding at least an anionic polymerization catalyst and an anionic polymerization initiator to substantially anhydrous ω-lactam after fixing a reinforcing plate to the support by arranging a support base movably with respect to a mold bottom surface. The liquid was filled up to the inner groove part while overflowing from the casting part, and then the sealing material was sealed so as not to allow air to intervene on the liquid surface of the polymerizable lactam liquid, and then the upper lid was placed and polymerized, and the polymerization was completed. Polyamide resin to release the molded body afterwards In the manufacturing method of the form.
【0010】この発明によれば、重合性ラクタム液を1
つ以上の窪み状注型部から溢れさせつつ内溝部まで充満
させ、続いて重合性ラクタム液の液面に空気を介在させ
ないように遮蔽材をシールした後に上蓋を設置して重合
するため、表面の重合不足やヒケ発生を阻止でき、表面
加工を短時間に少なくとも1つ以上の成形体を得ること
ができる。そして、得られたポリアミド樹脂が重合中に
発生する収縮応力の残留を阻止して均一に収縮すること
で補強板へ良好に抱きつき、また機械的にもロックされ
るため、ポリアミド樹脂が補強板から容易に抜けること
がない。According to the present invention, the polymerizable lactam liquid is
Fill the inner groove part while overflowing from one or more hollow casting parts, then seal the shielding material so that air does not intervene on the liquid surface of the polymerizable lactam liquid, then install the upper lid and polymerize, Insufficient polymerization and sink marks can be prevented, and at least one molded body can be obtained in a short time in surface processing. Then, the obtained polyamide resin prevents the residual shrinkage stress generated during the polymerization and uniformly shrinks, so that it is well hugged to the reinforcing plate and is also mechanically locked, so that the polyamide resin is removed from the reinforcing plate. It does not come off easily.
【0011】本願請求項2記載の発明は、使用する金型
がアルミニウム製であるポリアミド樹脂成形体の製造方
法にあり、熱伝導率の良好な金型になり、短時間に金型
が昇温して重合時間を短縮することができる。The invention according to claim 2 of the present application resides in a method for producing a polyamide resin molded article in which a mold to be used is made of aluminum. The mold has good thermal conductivity, and the mold is heated in a short time. To shorten the polymerization time.
【0012】本願請求項3記載の発明は、鉄製の支持台
を磁力により注型部から引き抜き、成形体を金型から脱
型するポリアミド樹脂成形体の製造方法にあり、磁力を
用いた手段で成形体を容易に脱型することができる。[0012] The invention according to claim 3 of the present application is a method for manufacturing a polyamide resin molded body, in which an iron support base is pulled out from a casting part by magnetic force, and the molded body is released from a mold. The molded article can be easily removed from the mold.
【0013】本願請求項4記載の発明は、補強板が側面
の周方向に沿って1つの溝状部もしくは凸状部を有して
いるポリアミド樹脂成形体の製造方法であり、得られた
ポリアミド樹脂が重合中に均一に収縮することで補強板
へ良好に抱きつき、また機械的にもロックされるため、
ポリアミド樹脂が補強板から容易に抜けることがない。[0013] The invention according to claim 4 of the present application is a method for producing a polyamide resin molded article in which the reinforcing plate has one groove-shaped portion or a convex portion along the circumferential direction of the side surface. Because the resin shrinks uniformly during polymerization, it satisfactorily embraces the reinforcing plate and is also mechanically locked,
The polyamide resin does not easily come off the reinforcing plate.
【0014】本願請求項5記載の発明は、補強板が周方
向に沿って所定の間隔をおきかつ厚み方向への回転防止
用の切り欠き溝を有しているポリアミド樹脂成形体の製
造方法にあり、ポリアミド樹脂が補強板から容易に抜け
ることなく、更にポリアミド樹脂が補強板から回転しに
くくなってポリアミド樹脂と補強板の結合力が高く、ギ
ア、ローラ、車輪等の用途に適用することができる。According to a fifth aspect of the present invention, there is provided a method for producing a polyamide resin molded article, wherein the reinforcing plates are provided at predetermined intervals along the circumferential direction and have notches for preventing rotation in the thickness direction. Yes, the polyamide resin does not easily come off the reinforcing plate, and the polyamide resin does not easily rotate from the reinforcing plate, so that the bonding strength between the polyamide resin and the reinforcing plate is high, and it can be applied to gears, rollers, wheels, etc. it can.
【0015】本願請求項6記載の発明は、内溝部から溢
れ出た重合性ラクタム液を外溝部に溜めるポリアミド樹
脂成形体の製造方法であり、金型から溢れ出た重合性ラ
クタム液を容易に回収でき、作業環境を汚染しなくな
る。The invention according to claim 6 of the present application is a method for producing a polyamide resin molded product in which the polymerizable lactam liquid overflowing from the inner groove portion is stored in the outer groove portion, and the polymerizable lactam solution overflowing from the mold is easily removed. It can be collected and does not pollute the working environment.
【0016】本願請求項7記載の発明は、金型の内壁面
が成形体を脱型しやすいようにテーパー面になっている
ポリアミド樹脂成形体の製造方法にあり、成形体が脱型
しやすくなっている。The invention according to claim 7 of the present application resides in a method for producing a polyamide resin molded article in which the inner wall surface of a mold is tapered so that the molded article can be easily removed from the molded article. Has become.
【0017】本願請求項8記載の発明は、遮蔽材が金属
箔である金属補強ポリアミド樹脂成形体の製造方法であ
り、金属箔により確実にシールすることができる。The invention according to claim 8 of the present application is a method for producing a metal-reinforced polyamide resin molded article in which the shielding material is a metal foil, and can be reliably sealed with the metal foil.
【0018】[0018]
【発明の実施の形態】図1は本発明の製造方法によって
得られたポリアミド樹脂成形体の平面図、図2は図1の
A−A断面図、図3は本発明のポリアミド樹脂成形体に
おいて使用する補強板の斜視図、図4は本発明のポリア
ミド樹脂成形体において使用する他の補強板の斜視図、
図5は本発明のポリアミド樹脂成形体の製造方法におい
て使用する金型の平面図、図6は図5のB−B断面図、
そして図7は図6のC部拡大図である。DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a plan view of a polyamide resin molded article obtained by the production method of the present invention, FIG. 2 is a sectional view taken along line AA of FIG. 1, and FIG. FIG. 4 is a perspective view of a reinforcing plate used, FIG. 4 is a perspective view of another reinforcing plate used in the polyamide resin molded article of the present invention,
5 is a plan view of a mold used in the method for producing a polyamide resin molded article of the present invention, FIG. 6 is a cross-sectional view taken along line BB of FIG.
FIG. 7 is an enlarged view of a portion C in FIG.
【0019】本発明の方法により製造されるポリアミド
樹脂製の成形体1は、たとえば図1及び図2に示すよう
な円盤体であり、図3に示すように中央部に貫通穴3
を、側面4の周方向に沿って1つの溝状部5を、そして
周方向に沿って所定の間隔をおき、かつ厚み方向に沿っ
て回転防止用の切り欠き溝6を有する金属製の補強板2
の外側にポリアミド樹脂9を装着した構造になってい
る。ポリアミド樹脂9の外周部には、後の機械加工によ
り歯部(図示せず)が形成され、高負荷用のギヤとして
使用される。この後加工する際に、貫通穴3が旋盤の把
持部に取り付けられる。The molded body 1 made of polyamide resin produced by the method of the present invention is, for example, a disk as shown in FIGS. 1 and 2, and has a through hole 3 at the center as shown in FIG.
Metal reinforcement having one groove portion 5 along the circumferential direction of the side surface 4 and a notch groove 6 for preventing rotation at a predetermined interval along the circumferential direction and along the thickness direction. Board 2
And a structure in which a polyamide resin 9 is attached to the outside. A tooth portion (not shown) is formed on the outer peripheral portion of the polyamide resin 9 by subsequent machining, and is used as a gear for high load. At the time of subsequent processing, the through hole 3 is attached to the grip portion of the lathe.
【0020】他の補強板2としては、図4に示すように
中央部に貫通穴3を、側面4の周方向に沿って1つの凸
状部7を、そして周方向に沿って所定の間隔をおき、か
つ厚み方向に沿って回転防止用の切り欠き溝6を有する
形状であってもよい。上記1つの溝状部5や凸状部7
は、ポリアミド樹脂が重合中に発生する収縮応力の残留
を阻止して均一に収縮することで補強板2へ良好に抱き
つき、また機械的にもロックされるため、ポリアミド樹
脂9が補強板2から容易に抜けることがない。また、切
り欠き溝6はポリアミド樹脂9が補強板2から回転する
のを阻止している。As shown in FIG. 4, another reinforcing plate 2 has a through hole 3 in the center, one convex portion 7 along the circumferential direction of the side surface 4, and a predetermined interval along the circumferential direction. And may have a cutout groove 6 for preventing rotation along the thickness direction. The one groove-like portion 5 and the convex portion 7
Is because the polyamide resin prevents shrinkage stress generated during polymerization from remaining, and uniformly shrinks, and is satisfactorily held on the reinforcing plate 2 and is also mechanically locked. It does not come off easily. The notch 6 prevents the polyamide resin 9 from rotating from the reinforcing plate 2.
【0021】図5に示す金型10は、熱伝導率の高い金
属材料、例えばアルミニウムからなる厚肉の成形部11
に少なくとも1つ以上の窪み状の注型部12を規則的に
配し、その成形部11の外周囲に連続した内溝部13
を、更にその外側に内溝部13から溢れ出た重合性ラク
タム液を回収して、作業環境の汚染を防止するための液
溜用の外溝部14を不連続に有している。内溝部13を
連続にすることにより、注型部12への空気の吸い込み
を阻止することができる。しかし、外溝部14は連続に
する必要はない。The mold 10 shown in FIG. 5 has a thick molded portion 11 made of a metal material having high thermal conductivity, for example, aluminum.
At least one or more recessed casting parts 12 are regularly arranged on the inside, and a continuous inner groove part 13 is formed around the outer periphery of the molding part 11.
In addition, an outer groove portion 14 for collecting a polymerizable lactam liquid overflowing from the inner groove portion 13 outside the inner groove portion 13 to prevent contamination of the working environment is provided discontinuously. By making the inner groove portion 13 continuous, suction of air into the casting portion 12 can be prevented. However, the outer grooves 14 need not be continuous.
【0022】各注型部12内の中心部には、図6と図7
に示すように、突起部15が配置され、支持台16を中
心位置に設置するためのガイド役となっている。該支持
台16は突起部15と嵌合して金型底面に対して移動自
在に設けられ、貫通穴3を挿入して補強板2を固定す
る。上蓋20は外周壁21と支持台16の各頭部に設置
される。尚、支持台16は金型底面に対して移動自在で
あれば、どのような設置構造であってもよい。例えば、
支持台16は金型底面から所定のストロークだけ移動可
能な設置構造であってもよい。また、上記支持台16の
壁面は、0.5〜7°のテーパー面にしてもよく、これ
により成形体1の脱型がより容易になる。FIGS. 6 and 7 show the center of each casting part 12.
As shown in FIG. 5, the projection 15 is arranged and serves as a guide for setting the support base 16 at the center position. The support base 16 is fitted to the projection 15 and is provided movably with respect to the bottom surface of the mold. The through hole 3 is inserted to fix the reinforcing plate 2. The upper lid 20 is installed on the outer peripheral wall 21 and each head of the support base 16. The support base 16 may have any installation structure as long as it can move with respect to the bottom surface of the mold. For example,
The support base 16 may have an installation structure that is movable from the bottom of the mold by a predetermined stroke. Further, the wall surface of the support base 16 may have a tapered surface of 0.5 to 7 °, which makes it easier to remove the molded body 1 from the mold.
【0023】図8は本発明の製造方法において注型した
重合性ラクタム液の表面を遮蔽材によりシールしている
ところの断面図であり、図9は本発明の製造方法におい
て上蓋をして重合しているところの断面図、そして図1
0は本発明の製造方法において成形体を脱型していると
ころの部分断面図を示す。FIG. 8 is a cross-sectional view of the surface of the polymerizable lactam liquid cast in the production method of the present invention, which is sealed with a shielding material. FIG. Cross section, and Figure 1
0 shows a partial cross-sectional view of the molded article being released from the mold in the production method of the present invention.
【0024】しかして、本発明の実施形態では、補強板
2の貫通穴3を支持台16に挿入して、補強板2を注型
部12に安定的に設置し、該金型10を100〜180
°Cに温度調節した熱板23上に置いた後、実質上無水
のω−ラクタムに少なくともアニオン重合触媒とアニオ
ン重合開始剤とを加えた重合性ラクタム液を各注型部1
2内および内溝部13に溢れ出る程度まで充満する。こ
の時、内溝部13から溢れ出た重合性ラクタム液は外溝
部14に収容される。Thus, in the embodiment of the present invention, the through-hole 3 of the reinforcing plate 2 is inserted into the support 16, and the reinforcing plate 2 is stably installed on the casting part 12, and ~ 180
After being placed on a hot plate 23 controlled at a temperature of ° C., a polymerizable lactam liquid obtained by adding at least an anionic polymerization catalyst and an anionic polymerization initiator to substantially anhydrous ω-lactam was added to each casting part 1.
2 and to the extent that it overflows into the inner groove 13. At this time, the polymerizable lactam liquid overflowing from the inner groove 13 is stored in the outer groove 14.
【0025】上記ω−ラクタムは脱水タンク内において
減圧下で脱水して実質上無水の状態にした後、窒素など
の不活性気体で置換される。脱水タンク中のω−ラクタ
ムは、計量されて2つの注型タンクへ入れられ、その後
所定量のアニオン重合触媒がω−ラクタムの入った一方
の注型タンクに、また所定量のアニオン重合開始剤がω
−ラクタムの入った他方の注型タンクに投入される。The ω-lactam is dehydrated in a dehydration tank under reduced pressure to make it substantially anhydrous, and then replaced with an inert gas such as nitrogen. The ω-lactam in the dehydration tank is weighed into two casting tanks, and then a predetermined amount of an anionic polymerization catalyst is added to one casting tank containing the ω-lactam and a predetermined amount of an anionic polymerization initiator. Is ω
-Into the other casting tank containing the lactam.
【0026】続いて、遮蔽材24を内溝部13の外側ま
で重合性ラクタム液の液面に空気を介在させないように
シールした後、上蓋20を設置して重合する。ここで使
用する遮蔽材24はアルミ箔を代表とする金属箔が好ま
しい。その後、上蓋20を置いて重合を進行させる。こ
のように、重合性ラクタム液を各注型部12内のみなら
ず内溝部13にまで溢れ出る程度充満し、この状態で遮
蔽材24を内溝部13の外側までシールすると、遮蔽材
24と金型10の間隙からの空気の吸い込みを防ぐこと
ができ、不良品の発生を押さえることができる。Subsequently, the shielding material 24 is sealed to the outside of the inner groove portion 13 so that air does not intervene on the liquid surface of the polymerizable lactam liquid, and then the upper lid 20 is installed to perform polymerization. The shielding material 24 used here is preferably a metal foil represented by an aluminum foil. Then, the polymerization is advanced by placing the upper lid 20. As described above, the polymerizable lactam liquid is filled to the extent that it overflows not only into each casting portion 12 but also into the inner groove portion 13. In this state, when the shielding material 24 is sealed to the outside of the inner groove portion 13, the shielding material 24 and the metal are filled. It is possible to prevent air from being sucked from the gap of the mold 10 and to suppress the occurrence of defective products.
【0027】重合が完了すると、上蓋20を取り除き、
磁石25を用いて鉄製の支持台16を磁力により注型部
12から引き抜き、同時に成形体1を脱型する。成形体
1の上面27には未反応の液状モノマーが残存すること
がなく、外観の良好な成形体1を得ることができた。When the polymerization is completed, the upper lid 20 is removed,
Using the magnet 25, the iron support 16 is pulled out of the casting part 12 by magnetic force, and at the same time, the molded body 1 is released. The unreacted liquid monomer did not remain on the upper surface 27 of the molded article 1, and the molded article 1 having a good appearance could be obtained.
【0028】本発明で使用する上記ω−ラクタムは、実
質上無水のα−ピペリドン、ε−カプロラクタム、ω−
ラウロラクタム、ω−エナントラクタム、ω−カプリル
ラクタム、ω−デカノラクタム、ω−ウンデカノラクタ
ム、等あるいはこれらの2種以上の混合物であり、工業
的に有利なラクタムはε−カプロラクタムとω−ラウロ
ラクタムである。The ω-lactam used in the present invention is substantially anhydrous α-piperidone, ε-caprolactam, ω-lactam.
Laurolactam, ω-enantholactam, ω-caprylactam, ω-decanolactam, ω-undecanolactam, or a mixture of two or more thereof. Industrially advantageous lactams are ε-caprolactam and ω-laurolactam. It is.
【0029】また、本発明で使用するアニオン重合触媒
は、水素化ナトリウム、水素化リチウム、ナトリウム、
カリウム等公知のω−ラクタムの重合触媒を使用するこ
とができ、その添加量はω−ラクタムに対して0.1〜
2.0モル%である。そして、アニオン重合開始剤とし
ては、例えばN−アセチル−ε−カプロラクタム、イソ
シアネート、ジイソシアネート、尿素誘導体、ウレタ
ン、イソシアヌレート誘導体であり、その添加量はω−
ラクタムに対して0.05〜1.0モル%の範囲が好ま
しい。Further, the anionic polymerization catalyst used in the present invention includes sodium hydride, lithium hydride, sodium,
Known ω-lactam polymerization catalysts such as potassium can be used, and the amount of addition is 0.1 to ω-lactam.
2.0 mol%. Examples of the anionic polymerization initiator include N-acetyl-ε-caprolactam, isocyanate, diisocyanate, urea derivative, urethane, and isocyanurate derivative.
The range of 0.05 to 1.0 mol% with respect to the lactam is preferred.
【0030】上記製造方法では、アニオン重合触媒をω
−ラクタムに添加し溶解した後、アニオン重合開始剤を
注型時または注型後に添加混合する方法、またはアニオ
ン重合触媒を含むω−ラクタムとアニオン重合開始剤を
含むω−ラクタムとを注型時または注型後に添加混合す
る方法によって調整する。また、ω−ラクタムの重合は
100〜210°Cの温度で実施可能であるが、好まし
くは130〜180°Cである。In the above production method, the anionic polymerization catalyst
A method of adding and mixing an anionic polymerization initiator after or after adding and dissolving to a lactam, or a method of casting an ω-lactam containing an anionic polymerization catalyst and an ω-lactam containing an anionic polymerization initiator. Alternatively, it is adjusted by a method of adding and mixing after casting. Further, the polymerization of ω-lactam can be carried out at a temperature of 100 to 210 ° C., preferably 130 to 180 ° C.
【0031】尚、本発明方法を実施するに際して、上記
成分以外に重合を阻害しない油類、ワックス、ステアリ
ン酸亜鉛、ステアリン酸カルシウム等の滑剤や、カーボ
ン繊維、ガラス繊維等の補強材を添加することも可能で
ある。In carrying out the method of the present invention, other than the above-mentioned components, oils, waxes, lubricants such as zinc stearate and calcium stearate, which do not inhibit polymerization, and reinforcing materials such as carbon fiber and glass fiber are added. Is also possible.
【0032】[0032]
【実施例】以下、実施例により本発明をより詳細に説明
する。 実施例1 脱水した後、脱水タンク中のε−カプロラクタムが計量
されて2つの注型タンクへ入れられ、一方の注型タンク
へ1,250g、他方の注型タンクへ1,250g入れ
た後、一方の注型タンクへ4.0gの水素化ナトリウム
(63%油性)を添加して溶解させ、更に他方の注型タ
ンクへ5.6gトリフェニルイソシアヌレートを添加し
た。この間、注型タンク内を大気圧下で窒素を流しつ
つ、更に重合性ラクタム液を125°Cまで昇温しなが
らミキシングした。The present invention will be described in more detail with reference to the following examples. Example 1 After dehydration, ε-caprolactam in a dehydration tank was weighed and put into two casting tanks, and after putting 1,250 g into one casting tank and 1,250 g into the other casting tank, 4.0 g of sodium hydride (63% oil) was added and dissolved in one casting tank, and 5.6 g of triphenylisocyanurate was added to the other casting tank. During this time, the polymerizable lactam solution was mixed while the temperature was raised to 125 ° C. while flowing nitrogen in the casting tank under atmospheric pressure.
【0033】図6に示すような支持台が底面に対して移
動可能に設置したアルミニウム製の金型(内径95m
m、深さ23mm)を170°Cに設定した熱板の上に
置いた後、図3に示すような中央部に貫通穴、側面の周
方向に沿って1つの溝状部、そして周方向に沿って所定
の間隔をおき、かつ厚み方向に沿って4つの回転防止用
の切り欠き溝を有する鉄製の補強板を注型部内の支持台
に設置した。An aluminum mold (with an inner diameter of 95 m) in which a support table as shown in FIG.
m, a depth of 23 mm) on a hot plate set at 170 ° C., a through hole in the center as shown in FIG. 3, one groove along the circumferential direction of the side surface, and a circumferential direction. And a reinforcing plate made of iron having four notch grooves for preventing rotation along the thickness direction was placed on the support in the casting part.
【0034】その後、上記ミキシングした重合性ラクタ
ム液を注型部内と内溝部に溢れ出るまで流し込んだ後、
アルミ箔からなる遮蔽材を重合性ラクタム液の液面に空
気を介在させないようにシールした後、上蓋を設置して
重合した。After that, the above-mentioned mixed polymerizable lactam solution was poured into the casting portion and the inner groove portion until it overflowed.
After a shielding material made of an aluminum foil was sealed on the liquid surface of the polymerizable lactam liquid so as not to allow air to intervene, an upper lid was provided to perform polymerization.
【0035】重合が完了すると、上蓋を取り除き、磁石
を用いて鉄製の支持台を磁力により注型部から引き抜
き、容易に成形体を脱型することができた。成形体の上
面には未反応の液状モノマーが残存することがなく、ま
た局部的なヒケの発生もなく外観の良好な成形体を得る
ことができた。When the polymerization was completed, the upper lid was removed, and the iron support was pulled out from the casting portion by a magnet using a magnet, and the molded body could be easily removed from the mold. An unreacted liquid monomer did not remain on the upper surface of the molded article, and a molded article having a good appearance could be obtained without local sink marks.
【0036】また、成形したポリアミド樹脂製の成形体
の補強板抜き試験を行った。この補強板抜き試験は、環
境温度−40°C、20°C、100°Cでおいて成形
体をオートグラフの支持台に設置し、補強板を加圧しな
がらそのときの補強板抜き量と荷重を求めて、補強板が
抜ける時の荷重を求めた。その結果、補強板は−40°
C、20°Cにおいて50kNでは抜けることがなかっ
たが、100°Cになるとポリアミド樹脂が40kNで
割れずに抜けた。しかし、いずれも良好な結合力を有し
ていることが確認できた。A test for removing a reinforcing plate from the molded body made of a polyamide resin was conducted. This reinforcing plate removal test was performed by placing the molded body on a support stand of an autograph at an environmental temperature of -40 ° C, 20 ° C, and 100 ° C, and pressing the reinforcing plate while pressing the reinforcing plate. The load was determined, and the load when the reinforcing plate came off was determined. As a result, the reinforcing plate is -40 °
C, the resin did not come off at 50 kN at 20 ° C., but at 100 ° C., the polyamide resin came off at 40 kN without cracking. However, it was confirmed that all had good bonding strength.
【0037】比較例1 実施例1と同様の補強板を入れた注型部内に重合性ラク
タム液を溢れ出ない状態で流し込んだ後、アルミ箔から
なる遮蔽材でシールして上蓋を置いて重合した。得られ
たポリアミド樹脂成形体の上面には、未反応の液状モノ
マーが残存し、深さ10mm程度の複数個のヒケが発生
して外観不良になっていた。COMPARATIVE EXAMPLE 1 A polymerizable lactam solution was poured into a casting section containing a reinforcing plate similar to that in Example 1 without overflowing, and then sealed with a shielding material made of aluminum foil, and an upper lid was placed to polymerize. did. Unreacted liquid monomer remained on the upper surface of the obtained polyamide resin molded body, and a plurality of sink marks having a depth of about 10 mm were generated, resulting in poor appearance.
【0038】比較例2 実施例1と同様の補強板を入れた注型部内と内溝部に重
合性ラクタム液を溢れ出る状態で流し込んだ後、アルミ
箔からなる遮蔽材でシールせずに上蓋を置いて重合し
た。得られたポリアミド樹脂成形体の上面には、未反応
の液状モノマーが残存し、やはり深さ10mm程度のヒ
ケが発生した。COMPARATIVE EXAMPLE 2 A polymerizable lactam solution was poured into the casting part and the inner groove part in which a reinforcing plate similar to that in Example 1 was put, in a state of overflowing, and the upper lid was not sealed with a shielding material made of aluminum foil. Placed and polymerized. Unreacted liquid monomer remained on the upper surface of the obtained polyamide resin molded product, and again sink marks with a depth of about 10 mm occurred.
【0039】[0039]
【発明の効果】以上のように、本願請求項1記載の発明
では、重合性ラクタム液を1つ以上の窪み状注型部から
溢れさせつつ内溝部まで充満し、続いて重合性ラクタム
液の液面に空気を介在させないように遮蔽材をシールし
た後に上蓋を設置して重合するため、表面の重合不足や
ヒケ発生を阻止でき、表面加工を短時間に少なくとも1
つ以上の成形体を得ることができ、また得られたポリア
ミド樹脂が重合中に発生する収縮応力の残留を阻止して
均一に収縮することで補強板へ良好に抱きつき、また機
械的にもロックされるため、ポリアミド樹脂が補強板か
ら容易に抜けることがない等の効果がある。As described above, according to the first aspect of the present invention, the polymerizable lactam liquid is filled up to the inner groove while overflowing from one or more hollow casting parts. After sealing the shielding material so that air does not intervene on the liquid surface, the upper lid is placed and polymerization is performed. Therefore, insufficient polymerization of the surface and generation of sink marks can be prevented, and surface processing can be performed at least in a short time.
One or more molded bodies can be obtained, and the obtained polyamide resin prevents shrinkage stress generated during polymerization from remaining and shrinks uniformly, so that it is well hugged to the reinforcing plate and mechanically locked. Therefore, there is an effect that the polyamide resin does not easily come off from the reinforcing plate.
【0040】本願請求項2記載の発明では、使用する金
型がアルミニウム製であるため、熱伝導率の良好な金型
になり、短時間に金型が昇温して重合時間を短縮するこ
とができる効果がある。According to the second aspect of the present invention, since the mold used is made of aluminum, the mold has good thermal conductivity, and the temperature of the mold is raised in a short time to shorten the polymerization time. There is an effect that can be.
【0041】本願請求項3記載の発明では、鉄製の支持
台を磁力により注型部から引き抜き、成形体を金型から
脱型するものであり、簡単にかつ容易に成形体を脱型す
ることができる効果がある。According to the third aspect of the present invention, the iron support is pulled out from the casting part by magnetic force, and the molded body is released from the mold. The molded body can be easily and easily released. There is an effect that can be.
【0042】本願請求項4記載の発明では、補強板が側
面の周方向に沿って1つの溝状部もしくは凸状部を有し
ているため、得られたポリアミド樹脂が重合中に均一に
収縮することで補強板へ良好に抱きつき、また機械的に
もロックされるため、ポリアミド樹脂が補強板から容易
に抜けることがない効果がある。In the invention according to claim 4 of the present application, since the reinforcing plate has one groove-shaped portion or convex portion along the circumferential direction of the side surface, the obtained polyamide resin uniformly shrinks during polymerization. By doing so, the resin is satisfactorily held on the reinforcing plate and also mechanically locked, so that there is an effect that the polyamide resin does not easily come off from the reinforcing plate.
【0043】本願請求項5記載の発明では、補強板が周
方向に沿って所定の間隔をおきかつ厚み方向への回転防
止用の切り欠き溝を有しているため、ポリアミド樹脂が
補強板から容易に抜けることなく、更にポリアミド樹脂
が補強板から回転しにくくなってポリアミド樹脂と補強
板の結合力が高く、ギア、ローラ、車輪等の用途に適用
することができる効果がある。According to the fifth aspect of the present invention, since the reinforcing plate is provided at predetermined intervals along the circumferential direction and has cutout grooves for preventing rotation in the thickness direction, the polyamide resin can be removed from the reinforcing plate. The polyamide resin does not easily come off, and the polyamide resin is less likely to rotate from the reinforcing plate, so that the bonding strength between the polyamide resin and the reinforcing plate is high, and the polyamide resin can be applied to gears, rollers, wheels, and the like.
【0044】本願請求項6記載の発明では、内溝部から
溢れ出た重合性ラクタム液を外溝部に溜めるため、金型
から溢れ出た重合性ラクタム液を容易に回収でき、作業
環境を汚染しなくなる効果がある。In the invention according to claim 6 of the present application, the polymerizable lactam liquid overflowing from the inner groove portion is stored in the outer groove portion, so that the polymerizable lactam liquid overflowing from the mold can be easily collected, and the working environment is contaminated. It has the effect of disappearing.
【0045】本願請求項7記載の発明では、金型の内壁
面が成形体を脱型しやすいようにテーパー面になってい
るため、成形体が容易に脱型しやすくなる効果がある。In the invention according to claim 7 of the present application, since the inner wall surface of the mold has a tapered surface so that the molded body can be easily removed from the mold, there is an effect that the molded body can be easily removed from the mold.
【0046】本願請求項8記載の発明では、遮蔽材とし
て金属箔を使用するため、確実にシールすることができ
る効果がある。According to the eighth aspect of the present invention, since the metal foil is used as the shielding material, there is an effect that the sealing can be surely performed.
【図1】本発明に係るポリアミド樹脂成形体の平面図で
ある。FIG. 1 is a plan view of a polyamide resin molded article according to the present invention.
【図2】図1のA−A断面図である。FIG. 2 is a sectional view taken along line AA of FIG.
【図3】本発明のポリアミド樹脂成形体において使用す
る補強板の斜視図である。FIG. 3 is a perspective view of a reinforcing plate used in the polyamide resin molded article of the present invention.
【図4】発明のポリアミド樹脂成形体において使用する
他の補強板の斜視図である。FIG. 4 is a perspective view of another reinforcing plate used in the polyamide resin molded article of the present invention.
【図5】本発明のポリアミド樹脂成形体の製造方法にお
いて使用する金型の平面図である。FIG. 5 is a plan view of a mold used in the method for producing a polyamide resin molded article of the present invention.
【図6】図5のB−B断面図である。FIG. 6 is a sectional view taken along line BB of FIG. 5;
【図7】図6のC部拡大図である。FIG. 7 is an enlarged view of a portion C in FIG. 6;
【図8】本発明の製造方法において注型した重合性ラク
タム液の表面を遮蔽材によりシールしているところの断
面図である。FIG. 8 is a cross-sectional view in which the surface of a polymerizable lactam liquid cast in the production method of the present invention is sealed with a shielding material.
【図9】本発明の製造方法において上蓋をして重合して
いるところの断面図を示す。FIG. 9 is a cross-sectional view showing a state in which polymerization is performed with a top lid in the production method of the present invention.
【図10】本発明の製造方法において成形体を脱型して
いるところの部分断面図を示す。FIG. 10 is a partial cross-sectional view showing a state where a molded article is released from a mold in the production method of the present invention.
1 成形体 2 補強板 3 貫通穴 5 溝状部 6 切り欠き溝 10 金型 11 成形部 12 注型部 13 内溝部 14 外溝部 15 突起部 16 支持台 20 上蓋 24 遮蔽材 25 磁石 DESCRIPTION OF SYMBOLS 1 Molded body 2 Reinforcement plate 3 Through hole 5 Groove part 6 Notch groove 10 Die 11 Molding part 12 Casting part 13 Inner groove part 14 Outer groove part 15 Projection part 16 Support stand 20 Top cover 24 Shielding material 25 Magnet
───────────────────────────────────────────────────── フロントページの続き Fターム(参考) 4F204 AA29 AD03 AH04 AH12 EA03 EA04 EB12 EF01 EF05 EF27 EK25 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4F204 AA29 AD03 AH04 AH12 EA03 EA04 EB12 EF01 EF05 EF27 EK25
Claims (8)
一体化したポリアミド樹脂成形体の製造方法において、
少なくとも1つ以上の窪み状注型部を配した成形部の外
周囲に連続した内溝部を設け、更にその外側に液溜用の
外溝部を設けた温度調節可能な金型を用意し、該金型の
各注型部に支持台を金型底面に対して移動自在に設置し
て補強板を上記支持台に固定した後、実質上無水のω−
ラクタムに少なくともアニオン重合触媒とアニオン重合
開始剤とを加えた重合性ラクタム液を注型部から溢れさ
せつつ内溝部まで充満し、続いて重合性ラクタム液の液
面に空気を介在させないように遮蔽材をシールした後、
上蓋を設置して重合し、重合が完了した後に成形体を脱
型することを特徴とするポリアミド樹脂成形体の製造方
法。1. A method for producing a polyamide resin molded body in which a polyamide resin is bonded to and integrated around a reinforcing plate,
Providing a temperature-adjustable mold having a continuous inner groove around the outer periphery of the molded part provided with at least one or more hollow casting parts, and further having an outer groove for a liquid reservoir on the outside thereof, After setting a support base movably with respect to the bottom of the mold at each casting part of the mold and fixing the reinforcing plate to the support base, substantially anhydrous ω-
A polymerizable lactam solution obtained by adding at least an anionic polymerization catalyst and an anionic polymerization initiator to a lactam is filled from the casting portion to the inner groove while overflowing from the casting portion. After sealing the material,
A method for producing a polyamide resin molded article, comprising: installing a top lid, polymerizing, and removing the molded article after the polymerization is completed.
求項1記載のポリアミド樹脂成形体の製造方法。2. The method according to claim 1, wherein the mold used is made of aluminum.
き抜き、成形体を金型から脱型する請求項1または2記
載のポリアミド樹脂成形体の製造方法。3. The method for producing a polyamide resin molded article according to claim 1, wherein the iron support is pulled out from the casting part by magnetic force, and the molded article is released from the mold.
状部もしくは凸状部を有している請求項1、2または3
記載のポリアミド樹脂成形体の製造方法。4. The reinforcing plate has one groove or convex along the circumferential direction of the side surface.
The method for producing a polyamide resin molded article according to the above.
きかつ厚み方向への回転防止用の切り欠き溝を有してい
る請求項4記載のポリアミド樹脂成形体の製造方法。5. The method for producing a polyamide resin molded article according to claim 4, wherein the reinforcing plate is provided at predetermined intervals along a circumferential direction and has cutout grooves for preventing rotation in the thickness direction.
外溝部に溜める請求項1、2または3記載のポリアミド
樹脂成形体の製造方法。6. The method for producing a polyamide resin molded article according to claim 1, wherein the polymerizable lactam liquid overflowing from the inner groove is stored in the outer groove.
うにテーパー面になっている請求項1、2、3または6
記載のポリアミド樹脂成形体の製造方法。7. The mold according to claim 1, wherein the inner wall surface is tapered so that the molded body can be easily removed from the mold.
The method for producing a polyamide resin molded article according to the above.
リアミド樹脂成形体の製造方法。8. The method according to claim 1, wherein the shielding material is a metal foil.
Priority Applications (1)
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JP26072198A JP3376286B2 (en) | 1998-09-16 | 1998-09-16 | Method for producing polyamide resin molded article |
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JP26072198A JP3376286B2 (en) | 1998-09-16 | 1998-09-16 | Method for producing polyamide resin molded article |
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JP2000084954A true JP2000084954A (en) | 2000-03-28 |
JP3376286B2 JP3376286B2 (en) | 2003-02-10 |
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005172802A (en) * | 2003-11-18 | 2005-06-30 | Murazumi Kogyo Kk | Plate for microscopic specimen |
JP2006177875A (en) * | 2004-12-24 | 2006-07-06 | Murazumi Kogyo Kk | Plate for microscopic specimen |
CN112677415A (en) * | 2020-12-10 | 2021-04-20 | 何涛 | Injection molding closing device |
-
1998
- 1998-09-16 JP JP26072198A patent/JP3376286B2/en not_active Expired - Lifetime
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2005172802A (en) * | 2003-11-18 | 2005-06-30 | Murazumi Kogyo Kk | Plate for microscopic specimen |
JP2006177875A (en) * | 2004-12-24 | 2006-07-06 | Murazumi Kogyo Kk | Plate for microscopic specimen |
CN112677415A (en) * | 2020-12-10 | 2021-04-20 | 何涛 | Injection molding closing device |
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JP3376286B2 (en) | 2003-02-10 |
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