JP4412686B2

JP4412686B2 - Urethane elastomer manufacturing method and collision mixing equipment

Info

Publication number: JP4412686B2
Application number: JP09785599A
Authority: JP
Inventors: 俊成三浦
Original assignee: Canon Inc
Current assignee: Canon Inc
Priority date: 1999-04-05
Filing date: 1999-04-05
Publication date: 2010-02-10
Anticipated expiration: 2019-04-05
Also published as: JP2000293081A

Description

【０００１】
【発明の属する技術分野】
本発明は、熱硬化性ウレタンエラストマーの製法、および該製法に好適に用いられる衝突混合装置に関する。
【０００２】
【従来の技術】
電子写真複写機、レーザービームプリンターにおいて、感光ドラムに残留するトナーの除去は、一般的にクリーニングブレードで行われている。
該クリーニングブレードは、耐摩耗性等の力学的特性に優れるポリウレタンが、一般的に用いられている。
【０００３】
クリーニングブレード用ポリウレタンは、通常主剤と硬化剤からなる熱硬化性ウレタンエラストマー原料を混合し、成形型に充填して硬化させ、この硬化物を脱型することにより製造される。
【０００４】
上記主剤と硬化剤の混合において、従来メカニカル混合法が行われている。
メカニカル混合法では、混合室壁や回転羽根に硬化物が付着するのを防止するため、主剤および硬化剤として反応速度が遅いものが用いられている。
したがって、型に充填してから脱型するまでの時間が長くなり、製造効率が悪化するという問題があった。
【０００５】
この問題を解決するため、反応速度が速い主剤等を使用できる衝突混合法が提案されている。この混合法は、混合が極めて短い時間で行われるため、硬化速度が速い主剤および硬化剤を使用することが可能となり、製造効率を向上させることができる。
【０００６】
しかしながら、この衝突混合法には、注入の停止、再開を繰り返すと成型物に気泡が発生するという問題がある。気泡が発生すると、クリーニングブレードの場合、エッジ部に欠陥が生じ、部分的に感光ドラムでの残留トナーの掻き落としが不可能となる。
このような衝突混合によって発生しやすい気泡をなくすために、特開平７-３３４０５３号では、注入停止時に混合物を混合室に存在させておく方法が提案されている。
この方法は、注入停止時に混合室に混合物が存在しているので、衝突混合再開時に混合物に気泡が巻き込まれないという長所がある。
【０００７】
【発明が解決しようとする課題】
しかしながら、上記の特開平７-３３４０５３号の示す衝突混合法では、注入の停止時にも、混合室に存在させている混合物の硬化反応が進行し、ゲル化することがさけられない。そのため、衝突混合再開後は、まずゲル化物が吐出され、その後に通常の混合物が吐出される。
このようにゲル化したものと、そうでないものを同一の型に注入すると、成型物の物性・寸法にばらつきが出るおそれがあり、また、目視によっても揺らぎが確認できる。
【０００８】
本発明は上記に鑑みなされたもので、気泡が無く、物性・寸法のばらつきが小さく、生産効率が良く、且つ低コストなポリウレタンエラストマーの製法およびそれに用いる衝突混合装置を提供することを目的とする。
【０００９】
上記目的を達成するため、本発明は、相対向する二つの流入口と混合物のための流出口とを有する混合室、該混合室に制御滑り弁兼クリーニングピストン１が配置され、該制御滑り弁兼クリーニングピストン１が前記混合室に対して流入口を同時に遮断する位置、流入口を同時に解放する位置、および混合物を前記混合室から排出させる位置の間で往復運動を可能ならしめ、且つ前記流入口の一方から予め減圧下で脱気した熱硬化ウレタンエラストマー原料主剤を高圧下で注入すると同時に、他方の流入口から予め減圧下で脱気した熱硬化ウレタンエラストマー原料硬化剤を高圧下で注入して両者を衝突混合させる衝突混合装置により混合せしめ、得られた混合物を前記混合室の流出口から略Ｌ字形に接続した導管への流出制御滑り弁兼クリーニングピストン２を有する導管に流出させ、該導管の端部から金型または回転する円筒型に熱硬化ウレタンエラストマーを注入してウレタンエラストマーを製造するに際し、前記混合物の注入停止時には、前記混合室のクリーニングピストンの先端を、混合物を混合室から排出させる位置に移動し混合物を混合室から導管に排出し、その位置で制御滑り弁兼クリーニングピストン１を停止させ、次いで、導管の流入制御滑り弁兼クリーニングピストン２の先端を、導管の吐出口まで移動させ混合物を導管から排出させて、その位置でクリーニングピストンを停止させることによりウレタンエラストマーを得ることを特徴とするウレタンエラストマーの製法とする構成を有する。
【００１０】
また、上記目的を達成するため、本発明は、注入停止から注入再開の間に、導管の制御滑り弁兼クリーニングピストン２と同軸上で対向する制御滑り弁３を導管に挿入し、制御滑り弁兼クリーニングピストンの先端に突き当て、導管の制御滑り弁兼クリーニングピストン２を混合物流出口まで押し戻し、衝突混合を再開するときには、混合物の流動速度に合わせて制御滑り弁３を吐出口方向に後退させ吐出口を開くことを特徴とするウレタンエラストマーの製法とする構成を有する。
【００１１】
また、上記目的を達成するため、本発明は、導管の側面に、金型または円筒型に吐出するための穴をあけ、注入停止時には導管の制御滑り弁兼クリーニングピストン２を、その穴の位置まで進入させ混合物をその穴から排出させ、注入停止から注入再開の間に、導管の制御滑り弁兼クリーニングピストン２と同軸上で対向する制御滑り弁３を、制御滑り弁兼クリーニングピストンの先端に突き当て、導管の制御滑り弁兼クリーニングピストン２を混合物流出口まで押し戻し、衝突混合を再開するときには、混合物の流動速度に合わせて制御滑り弁３を、前記側面の吐出口方向に後退させ吐出口を開くことを特徴とするウレタンエラストマーの製法とする構成を有する。
【００１２】
また上記目的を達成するため、本発明は、注入停止時には、導管内の一部を真空にしておくウレタンエラストマーの製法とする構成を有する。また上記の目的を達成するため、本発明の衝突混合装置は、上記のような構造・機能を有するように構成される。
【００１３】
(作用)
上記課題を解決するための本発明においては、混合室および導管内に、混合物を存在させることなく、制御滑り弁を存在させておくこと、または真空にしておくことにより、吐出物が泡を包含することなく、均一な性状の吐出が可能になることを見いだしたことに基づく構成を有する。
【００１４】
【発明の実施の形態】
以下、本発明の実施態様を具体的に説明する。
本発明によるウレタンエラストマーの製造は、ウレタンエラストマー成形用主剤、硬化剤、衝突混合装置および成形用型を用いて行われる。
上記主剤および硬化剤は、通常の衝突混合で用いられているものを用いることができる。上記主剤および硬化剤は、温度７０〜９０℃、好ましくは８０℃で予備加熱し、衝突混合装置のタンクにそれぞれ充填し、減圧下脱気処理を行う。
【００１５】
この衝突混合による製法を、衝突混合、および注入停止の二つの時期に大別して説明する。まず、衝突混合時は、図１に示すように、相対向する二つの流入口と混合物のための流出口とを有する混合室で、前記混合室に制御滑り弁兼クリーニングピストンが配置されており、この制御滑り弁兼クリーニングピストン１が前記混合室に対して流入口を同時に遮断する位置と、流入口を同時に解放する位置、および混合物を混合室から排出させる位置の間で往復運動可能である混合室に、上記流入口の一方から予め減圧下で脱気した熱硬化ウレタンエラストマー原料の主剤を高圧下で混合室に注入すると同時に、他方の流入口から予め減圧下で脱気した熱硬化ウレタンエラストマー原料の硬化剤を高圧下で注入して両者を衝突混合させ、この混合物を上記混合室の流出口から略Ｌ字形に接続した、導管への流出制御滑り弁兼クリーニングピストン２を有する導管に流出させ、該導管の端部から金型または回転する円筒型に熱硬化ウレタンエラストマーを注入する。
【００１６】
一方、上記混合物の注入停止時には、上記混合室のクリーニングピストンの先端を混合物を混合室から排出させる位置に移動し混合物を混合室から導管に排出し、その位置で制御滑り弁兼クリーニングピストン１を停止させる。
【００１７】
注入停止から注入再開の間に、導管の制御滑り弁兼クリーニングピストン２と同軸上で対向する制御滑り弁３を導管に挿入し制御滑り弁兼クリーニングピストンの先端に突き当て、導管の制御滑り弁兼クリーニングピストン２を混合物流出口まで押し戻し、衝突混合を再開するときには、混合物の流動速度に合わせて制御滑り弁３を吐出口方向に後退させ吐出口を開く。
【００１８】
上記制御滑り弁３を吐出口方向に後退させる際、吐出量および吐出圧を検知するセンサおよび駆動制御を設けて、吐出量、および吐出圧を安定に保ちながら上記制御滑り弁３を吐出口方向に後退させることもできる。
【００１９】
また実施例２(図２参照)のように、導管の側面に穴を開けたものを使用することもできる。本発明によるクリーニングブレードおよびその製法においては、上記のような製法により製造されたクリーニングブレードおよびその製法を含むものである。
【００２０】
また本発明の衝突混合装置は、上記のような衝突混合を可能ならしめるよう構成される衝突混合装置を含むものである。
【００２１】
【実施例】
以下、本発明の詳細を実施例により図面に基づいて説明するが、本発明がこれらによってなんら限定されるものではない。
【００２２】
[実施例１]
請求項２記載の方式により調製したウレタンエラストマーは、泡・揺らぎを目視で確認したところ、いずれも皆無であった。。
【００２３】
[実施例２]
請求項３記載の方式により調製したウレタンエラストマーは、泡・揺らぎを目視で確認したところ、いずれも皆無であった。
【００２４】
[実施例３]
請求項４記載の方式により調製したウレタンエラストマーは、泡・揺らぎを目視で確認したところ、いずれも皆無であった。
【００２６】
[比較例１]
注入停止時に混合室、導管に混合物を存在させてから、衝突混合をして得られたウレタンエラストマーおよびクリーニングブレード(特開平７-３３４０５３の示す方式と同じ)は、泡・揺らぎを目視で確認したところ、泡の存在は認められなかったが、揺らぎは存在が認められた。
【００２７】
【表１】

【００２８】
【発明の効果】
本発明により、混合室および導管内に、混合物を存在させることなく、制御滑り弁を存在させておくこと、または真空にしておくことにより、吐出物が泡を包含することなく、均一な性状の吐出が可能になる。
また、本発明の製法により製造したクリーニングブレードは、泡による欠陥が無く、全幅にわたって良好なクリーニング性が得られる等の顕著な効果を奏する。
【図面の簡単な説明】
【図１】本発明の実施例１における衝突混合手段、混合室の概要を示す模式説明図。
【図２】本発明の実施例２における衝突混合手段、混合室の概要を示す模式説明図。
【符号の説明】
１制御滑り弁兼クリーニングピストン
２導管の流出制御滑り弁兼クリーニングピストン
３制御滑り弁[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a thermosetting urethane elastomer , and a collision mixing apparatus suitably used for the production method .
[0002]
[Prior art]
In electrophotographic copying machines and laser beam printers, toner remaining on the photosensitive drum is generally removed by a cleaning blade.
As the cleaning blade, polyurethane having excellent mechanical properties such as wear resistance is generally used.
[0003]
A polyurethane for a cleaning blade is usually produced by mixing thermosetting urethane elastomer raw materials composed of a main agent and a curing agent, filling a mold and curing it, and demolding the cured product.
[0004]
Conventionally, a mechanical mixing method is performed in mixing the main agent and the curing agent.
In the mechanical mixing method, in order to prevent the cured product from adhering to the mixing chamber wall and the rotary blade, those having a slow reaction rate are used as the main agent and the curing agent.
Therefore, there is a problem that the time from filling the mold to removing the mold becomes longer, and the production efficiency is deteriorated.
[0005]
In order to solve this problem, a collision mixing method in which a main agent or the like having a high reaction rate can be used has been proposed. In this mixing method, since mixing is performed in an extremely short time, it becomes possible to use a main agent and a curing agent having a high curing rate, and the production efficiency can be improved.
[0006]
However, this collision mixing method has a problem that bubbles are generated in the molded product when the injection is repeatedly stopped and restarted. When bubbles are generated, a defect occurs in the edge portion in the case of the cleaning blade, and it is impossible to partially scrape off the residual toner on the photosensitive drum.
In order to eliminate such bubbles that are likely to be generated by collision mixing, Japanese Patent Application Laid-Open No. 7-334053 proposes a method of allowing the mixture to exist in the mixing chamber when the injection is stopped.
This method has an advantage that bubbles do not get involved in the mixture when collision mixing is resumed because the mixture exists in the mixing chamber when the injection is stopped.
[0007]
[Problems to be solved by the invention]
However, in the collision mixing method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 7-334053, even when injection is stopped, the curing reaction of the mixture present in the mixing chamber proceeds and gelation cannot be avoided. Therefore, after restarting the collision mixing, the gelled material is discharged first, and then the normal mixture is discharged.
When the gelled and non-gelled ones are injected into the same mold, the physical properties and dimensions of the molded product may vary, and fluctuations can be confirmed visually.
[0008]
The present invention has been made in view of the above, and it is an object of the present invention to provide a polyurethane elastomer production method and a collision mixing apparatus used therefor that are free of bubbles, have small variations in physical properties and dimensions, have good production efficiency, and are low in cost. .
[0009]
In order to achieve the above object, the present invention provides a mixing chamber having two opposed inlets and an outlet for a mixture, a control slip valve / cleaning piston 1 disposed in the mixing chamber, and the control slip valve. The cleaning piston 1 enables reciprocating movement between a position where the inlet is simultaneously blocked with respect to the mixing chamber, a position where the inlet is simultaneously released, and a position where the mixture is discharged from the mixing chamber. A thermosetting urethane elastomer raw material main agent that has been degassed in advance under reduced pressure from one of the inlets is injected under high pressure, and at the same time, a thermosetting urethane elastomer raw material hardener that has been deaerated in advance under reduced pressure is injected under high pressure from the other inlet. The mixture is mixed by a collision mixing device that collides and mixes the two, and the resulting mixture flows from the outlet of the mixing chamber to a conduit connected in a substantially L shape. When the thermosetting urethane elastomer is produced by pouring out from the end of the conduit into a mold or a rotating cylindrical mold, the urethane is produced. The tip of the cleaning piston is moved to a position where the mixture is discharged from the mixing chamber, the mixture is discharged from the mixing chamber to the conduit, and the control slip valve / cleaning piston 1 is stopped at that position. It has a configuration as a method for producing a urethane elastomer characterized in that a urethane elastomer is obtained by moving the tip of the cleaning piston 2 to the discharge port of the conduit, discharging the mixture from the conduit, and stopping the cleaning piston at that position. .
[0010]
In order to achieve the above object, the present invention inserts a control slip valve 3 coaxially facing the control slip valve / cleaning piston 2 of the conduit between the stop of the injection and the restart of the injection. When the collision control is restarted, the control slip valve 3 is moved back in the direction of the discharge port in accordance with the flow rate of the mixture. It has the structure made into the manufacturing method of the urethane elastomer characterized by opening a discharge outlet.
[0011]
In order to achieve the above object, the present invention has a hole for discharging into a mold or a cylinder on the side of the conduit, and when the injection is stopped, the control slip valve / cleaning piston 2 of the conduit is positioned at the position of the hole. The control slip valve 3 that is coaxially opposed to the control slip valve / cleaning piston 2 of the conduit is disposed at the tip of the control slip valve / cleaning piston between the stop of injection and the restart of injection. When the collision control is resumed by pushing the conduit control slip valve / cleaning piston 2 back to the mixing flow outlet and restarting the impingement mixing, the control slip valve 3 is moved backward in the direction of the discharge port on the side surface in accordance with the flow rate of the mixture. And having a configuration in which the urethane elastomer is produced.
[0012]
The order to achieve the above object, the present invention is, when the injection is stopped, that a portion of the conduit having a structure that the preparation of the urethane elastomer to keep the vacuum. In order to achieve the above object, the collision mixing apparatus of the present invention is configured to have the structure and function as described above.
[0013]
(Action)
In the present invention for solving the above-described problems, the discharge material contains bubbles by allowing a control slip valve to exist in the mixing chamber and the conduit without causing the mixture to exist, or by maintaining a vacuum. Therefore, it has a configuration based on the finding that it becomes possible to discharge with uniform properties.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be specifically described.
Production of the urethane elastomer according to the present invention is carried out using a urethane elastomer molding main agent, a curing agent, a collision mixing device and a molding die.
As the main agent and the curing agent, those used in normal collision mixing can be used. The main agent and the curing agent are preheated at a temperature of 70 to 90 ° C., preferably 80 ° C., filled in a tank of a collision mixing device, and degassed under reduced pressure.
[0015]
The production method by the collision mixing will be roughly divided into two periods of collision mixing and injection stop. First, at the time of collision mixing, as shown in FIG. 1, a control slip valve / cleaning piston is arranged in the mixing chamber having two inflow ports facing each other and an outflow port for the mixture. The control slide valve / cleaning piston 1 can reciprocate between a position where the inlet is simultaneously shut off from the mixing chamber, a position where the inlet is simultaneously released, and a position where the mixture is discharged from the mixing chamber. The main component of the thermosetting urethane elastomer raw material previously deaerated under reduced pressure from one of the inlets into the mixing chamber is injected into the mixing chamber under high pressure, and at the same time, the thermosetting urethane deaerated beforehand under reduced pressure from the other inlet Elastomer raw material curing agent is injected under high pressure to collide and mix, and this mixture is connected in an L shape from the outlet of the mixing chamber. Allowed to flow out to the conduit having a piston 2, to inject thermosetting urethane elastomer cylindrical to die or rotating from the end of the conduit.
[0016]
On the other hand, when the injection of the mixture is stopped, the tip of the cleaning piston of the mixing chamber is moved to a position where the mixture is discharged from the mixing chamber, and the mixture is discharged from the mixing chamber to the conduit. Stop.
[0017]
Between the stoppage of injection and the resumption of injection, the control slip valve 3 that is coaxially opposed to the control slip valve / cleaning piston 2 of the conduit is inserted into the conduit and abuts against the tip of the control slip valve / cleaning piston. When the cleaning piston 2 is pushed back to the mixed flow outlet and the collision mixing is resumed, the control slip valve 3 is moved backward in the direction of the discharge port in accordance with the flow rate of the mixture to open the discharge port.
[0018]
When the control slip valve 3 is retracted in the direction of the discharge port, a sensor for detecting the discharge amount and discharge pressure and a drive control are provided, and the control slip valve 3 is moved in the direction of the discharge port while keeping the discharge amount and discharge pressure stable. It can also be retreated.
[0019]
In addition, as in Example 2 (see FIG. 2), it is also possible to use a pipe having a hole in the side surface. The cleaning blade and the manufacturing method thereof according to the present invention include the cleaning blade manufactured by the above manufacturing method and the manufacturing method thereof.
[0020]
The collision mixing apparatus of the present invention includes a collision mixing apparatus configured to enable the collision mixing as described above.
[0021]
【Example】
Hereinafter, the details of the present invention will be described with reference to the drawings by way of examples. However, the present invention is not limited to these examples.
[0022]
[Example 1]
The urethane elastomer prepared by the method according to claim 2 was confirmed to have no bubbles or fluctuations, and none was found. .
[0023]
[Example 2]
The urethane elastomer prepared by the method according to claim 3 was confirmed to have no bubbles or fluctuations, and none was found.
[0024]
[Example 3]
When the urethane elastomer prepared by the method of claim 4 was visually confirmed for bubbles and fluctuations, none was found.
[0026]
[Comparative Example 1]
The urethane elastomer and cleaning blade (same as the method shown in Japanese Patent Laid-Open No. 7-334053) obtained by collision mixing after the mixture was present in the mixing chamber and conduit when the injection was stopped were visually confirmed for bubbles and fluctuations. However, the presence of bubbles was not recognized, but the presence of fluctuation was recognized.
[0027]
[Table 1]

[0028]
【The invention's effect】
In accordance with the present invention, the presence of a controlled slip valve in the mixing chamber and conduit, or the presence of a vacuum, allows the discharge to have uniform properties without inclusion of bubbles. Discharge becomes possible.
In addition, the cleaning blade manufactured by the manufacturing method of the present invention has remarkable effects such as no defects due to bubbles and good cleaning properties over the entire width.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing an outline of a collision mixing means and a mixing chamber in Embodiment 1 of the present invention.
FIG. 2 is a schematic explanatory view showing an outline of a collision mixing means and a mixing chamber in Embodiment 2 of the present invention.
[Explanation of symbols]
1. Control slip valve / cleaning piston 2. Conduit outflow control slip valve / cleaning piston 3. Control slip valve

Claims

In a method for producing a urethane elastomer, a mixing chamber having two inlets facing each other and an outlet for a mixture, and a control slip valve / cleaning piston 1 are arranged in the mixing chamber, the control slip valve / cleaning piston 1 enables reciprocal movement between a position where the inlet is simultaneously blocked from the mixing chamber, a position where the inlet is simultaneously released, and a position where the mixture is discharged from the mixing chamber, and one of the inlets The thermosetting urethane elastomer raw material main ingredient previously degassed under reduced pressure from is injected under high pressure, and at the same time, the thermosetting urethane elastomer raw material hardener previously degassed under reduced pressure from the other inlet is injected under high pressure. The mixture is mixed by a collision mixing device for collision mixing, and the resulting mixture is discharged from the outlet of the mixing chamber to a conduit connected in a substantially L shape. When the urethane elastomer is produced by pouring out into the conduit having the valve / cleaning piston 2 and injecting the thermosetting urethane elastomer into the mold or the rotating cylindrical shape from the end of the conduit, the mixing is stopped when the injection of the mixture is stopped. The tip of the chamber cleaning piston is moved to a position where the mixture is discharged from the mixing chamber, the mixture is discharged from the mixing chamber into the conduit, at which position the control slide valve / cleaning piston 1 is stopped, and then the inflow control slip of the conduit. A process for producing a urethane elastomer, characterized in that a urethane elastomer is obtained by moving the tip of a valve / cleaning piston 2 to a discharge port of a conduit, discharging the mixture from the conduit, and stopping the cleaning piston at that position.

Between the stop of injection and the resumption of injection, a control slip valve 3 coaxially opposed to the control slip valve / cleaning piston 2 of the conduit is inserted into the conduit and abuts against the tip of the control slip valve / cleaning piston 1, When the control slip valve / cleaning piston 2 is pushed back to the outlet of the mixed flow and the collision mixing is resumed, the control slip valve 3 is moved backward in the direction of the discharge port in accordance with the flow rate of the mixture, and the discharge port is opened. Item 1. A method for producing a urethane elastomer according to Item 1.

A hole is formed in the side of the conduit for discharging into a mold or a cylinder. When the injection is stopped, the control slip valve / cleaning piston 2 of the conduit is advanced to the position of the hole, and the mixture is discharged from the hole to inject. Between the stop and the resumption of injection, the control slip valve 3 that is coaxially opposed to the control slip valve / cleaning piston 2 of the conduit is abutted against the tip of the control slip valve / cleaning piston, and the control slip valve / cleaning piston 2 of the conduit is 3. When pushing back to the outlet of the mixed flow and restarting the impingement mixing, the control slip valve 3 is moved backward in the direction of the outlet on the side surface in accordance with the flow rate of the mixture to open the outlet. Production method of urethane elastomer.

The method for producing a urethane elastomer according to any one of claims 1 to 3, wherein a part of the conduit is evacuated when the injection is stopped.

5. A collision mixing apparatus according to claim 1, wherein the mixing apparatus is an apparatus used in the method for producing a urethane elastomer according to any one of claims 1 to 4.