JP2004009175A

JP2004009175A - Surface treatment method for pestle and/or mortar for tablet-molding and pestle and/or mortar surface-treated for tablet-molding

Info

Publication number: JP2004009175A
Application number: JP2002163823A
Authority: JP
Inventors: Norinaga Niku; 二九　規長
Original assignee: Two Nine KK
Current assignee: Two Nine KK
Priority date: 2002-06-05
Filing date: 2002-06-05
Publication date: 2004-01-15
Anticipated expiration: 2022-06-05
Also published as: JP3999051B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a quite new surface treatment method for recycling a pestle and a mortar for tablet-molding which has been abolished before and prolonging a life of usage of the pestle and the mortar. <P>SOLUTION: The pestle 1 and the mortar for the tablet-molding abolished until now can be recycled by reforming a tablet-molding surface 2 by mixing and blowing a fine particle with compression air onto the tablet-molding surface 2 of the pestle 1 and/or the mortar used for the tablet-molding machine. A life of usage of the pestle 1 and the mortar is prolonged. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、半導体、菓子、薬、健康食品などを製造する打錠成形機に用いられる、杵および臼（プラスチック成形用金型も含む）の耐久性を向上させ、使用寿命を延長させるための表面改質に関する。特に、使用により打錠成形面の磨耗した打錠成形用の杵および臼をリサイクルするための表面改質に関する。
【０００２】
【従来の技術】
従来より、半導体、菓子、薬、健康食品などを製造する打錠成形機の杵および臼（プラスチック成形用金型も含む）のボディは、ＳＫＤ鋼などの素材から形成され、表面の研磨後に、さらに杵先端部の打錠部の凹面および臼の内壁の表面にクロム等の金属メッキなどを施すことが広く一般的に行われている。
このような杵または臼を打錠成形機で繰り返し使用すると、上述の杵先端部の凹面や臼の内壁面のクロムメッキが次第に磨耗して、打錠成形性が損なわれたり、製品に変形やバリが発生するため、製品の歩留りが低下するという問題が起こる。また、打錠時の衝撃により、クロムメッキが細かく剥離して、その破片が製品中に混入するという危険性も生じる。これまで、不要なクロムメッキ層を効果的に除去・修復する方法がなかった。
【０００３】
【発明が解決しようとする課題】
したがって、使用頻度の高い杵または臼の寿命は、約３〜６カ月とかなり短いのが現状であり、上述のような不具合の生じた杵や臼は修復されることなく、そのまま廃棄され新品と交換されてきた。しかし、昨今の環境問題およびコスト削減の観点等から、できるだけ廃棄物を削減して廃品をリサイクルして再利用する有効な手段が強く望まれていた。
【０００４】
本発明は、このような問題点を解消し、これまで廃棄されていた打錠成形機の杵および臼のリサイクルを可能ならしめ、杵および臼の使用寿命を延長させる、全く新しい表面処理方法を提供することを課題とする。
【０００５】
【課題を解決するための手段】
本発明は、打錠成形機に用いられる杵および／または臼の打錠成形面を改質するための処理であって、前記打錠成形面に、微粒子を圧縮空気に混合して吹き付けることによって、上記課題を解決したものである。
【０００６】
ここで、「微粒子を圧縮空気に混合して吹き付けること」とは、一定圧以上の噴射圧で微粒子を噴射して対象面に衝突させる、乾式のブラスト処理を意味し、この処理によって、表面形状を改質することが可能となる。微粒子の吹き付けによる改質の作用は、噴射圧および噴射される微粒子の形状、大きさ等に依存するが、ここでは、微粒子の衝突によって、打錠成形面の不具合、すなわち具体的には打錠成形性能の低下の原因となる打錠成形面の歪み、剥離、バリ等の異常部位が取り除かれたり、微細なクラックが封入されたりして、処理前よりも均質な表面に加工される。この方法によれば、上述のような打錠成形面の不具合が解消されて、引き続き行われるクロムメッキ等の表層処理が可能となるので、既存の打錠成形用の杵および臼の使用寿命を延長せしめることとなる。本発明により、吹き付け処理面の表面粗さがＲａで約１．３５μｍ以下に仕上げられることが望ましく、特に約０．１０〜０．３０μｍの範囲となることがより望ましい。
【０００７】
本発明の表面処理は、杵および／または臼のリサイクル処理に適用されることにより、従来までは廃棄して新品と交換するしかなかったような、打錠成形面の著しく磨耗した杵または臼についても、新品同様に再生できて再利用が可能となる。
【０００８】
また、表面の仕上がりの良好さや微粒子の扱い易さの観点から、微粒子は鉱石の微粒子が好ましく、その平均粒径は、約１０〜２００μｍが好ましい。特に、平均粒径の異なる２種類の微粒子を別々に使用することが好ましい。具体的には、初めに粒径のより大きな（粗い）微粒子で吹き付け処理をした後に、より小さな粒径の（細かい）微粒子で吹き付け処理を行うことが望ましい。このような方法であれば、まず粗い微粒子により、打錠成形面の剥離や、バリに挟まった異物等を効果的に除去できて、さらに細かい微粒子により、打錠成形面をより均質な面に加工することが可能となる。前記の粗い微粒子の平均粒径は、約３０〜２００μｍが望ましく、前記の細かい微粒子の平均粒径は約１０〜５０μｍであることが特に望ましい。
【０００９】
また、上記の微粒子を吹き付ける処理を施した表面に、さらに金属薄膜を形成するようにしたので、杵および臼の耐磨耗性や耐食性をより一層高めることとなる。金属薄膜として、クロムまたはチタンを含有するものが挙げられる。薄膜を形成する方法として、通常のメッキ法、例えば真空蒸着、スパッタリング、電気メッキおよび化学メッキ等が挙げられるが、特にＰＶＤ処理による窒化クロムの被膜が好適である。
【００１０】
また、打錠成形面の磨耗程度が一目でわかるようにするためには、前記金属薄膜が、互いに異なる金属を積層させてなるようにしたものが好ましい。このようなものであれば、最上層の金属薄膜が磨耗して、下層の金属薄膜が露出する状態を目視で確認できるので、杵または臼の使用寿命を的確かつ容易に把握し得ることとなる。使用寿命に達した杵および臼に、再び本発明の表面改質の処理を行うようにすれば、杵および臼のリサイクルを一層効率的に行うことが可能となる。
【００１１】
【発明の実施の形態】
以下に、本発明を実施するための形態について説明する。
【００１２】
図１は、本発明の一実施形態としての打錠成形用の杵を説明するための図である。打錠成形用の杵１とは、打錠成形機に取り付けられて使用される棒体状のもので、その先端部の打錠成形面２を、同じく打錠成形機に設けられた臼（図示しない）に押しつけることで、粉末やゲル状物から菓子、薬、健康食品、半導体等を成形加工する。打錠成形面２には、打錠成形する製品の形状に対応させたキャビテイ（凹み）が設けられている。杵１および臼のボディは、耐腐食性、強度等の観点から、ＳＫＤ６１などの鋼材から製造され、表面はクロム等の金属メッキ処理が施されている。このような杵１を打錠成形機で繰り返し使用して衝撃を与えると、打錠成形面２の金属メッキ層が次第に変形し、やがて剥離やヒビ割れが生じて、製品の成形が不可能になってくる。
【００１３】
上述のように磨耗した杵の打錠成形面２に対し、粒径が約１０〜２００μｍの鉱石の微粒子を吹き付けてブラスト処理する。鉱石の種類に特に限定はない。鉱石の微粒子は圧縮空気に混合され、約０．１〜２．５ｂａｒ圧で目的とするキャビテイに噴射する。まず打錠成形面２に粒径の粗い鉱石の微粒子を吹き付けた後に、粒径の細かい微粒子を吹き付ける順番の工程で行う。第一段階として、平均粒径が約３０〜２００μｍのやや角張った鉱石の微粒子を打錠成形面２に噴射して、剥離状態の金属メッキや、でこぼこに挟まった異物等を大まかに除去する。続いて、平均粒径が約１０〜５０μｍの細かい微粒子を打錠成形面２に噴射して、表面の不均一な凸凹をならして、より均質な表面に仕上げる。仕上がりの程度は、処理前の杵のメッキ状態や打錠成形面の磨耗具合にも依るが、処理後の表面粗さがＲａで０．１０〜０．３０μｍに仕上げるのが、後の金属メッキ処理を行う上で特に好ましい。次いで、余分な微粒子を取り除くための洗浄・洗浄を行い、クロム等の金属による薄膜処理を施す。こうして、磨耗して使用限界に至った杵をリサイクルして新品と同様の杵を提供することができる。
【００１４】
杵および臼にさらなる耐久性を付与するために、窒化金属による被膜を施すことも望ましい。特にＰＶＤ処理（イオンプレーティング）による窒化クロムの被膜が好適である。また、リサイクルした杵および臼を打錠成形機に用いた場合に、これらの使用限界を越えない範囲で安心して使用するためには、互いに異なる金属を積層させて薄膜を形成するようにしたものが特に好適である。例えば、下層に約１μｍの窒化チタンのコーティング層を設け、その上に窒化クロムのコーティング層を設けることが挙げられる。使用により窒化クロムが磨耗すると、窒化クロム（灰色帯びた金属光沢）の間から、窒化チタン特有の金属光沢（金色を帯びた色）が露出するので、使用限界を知る上での目安となる。また、下層に窒化クロムのコーティング層を設け、上層に窒化チタンのコーティング層を設けても構わない。
【００１５】
また、杵について行った上述の処理方法は、打錠成形用の臼についても適用される。これにより、従来の臼の使用寿命を大幅に延長させることが可能となる。
【００１６】
次に、実施例に基づいて、本発明を更に詳細に説明するが、実施例によって本発明が限定されるものではない。
【００１７】
実施例１：まず、打錠成形機に杵を取り付ける。杵はＳＫＤ６１製で、直径６．０ｍｍの棒状の杵の先端部には、打錠成形用の逆碗型のキャビティ（Ｒ＝１２．０ｍｍ）が設けられ、表面がクロムメッキされているものである。この杵に、重酸化ナトリウムを主成分とした粉末の錠剤加工成形を繰り返させて、先端部の打錠成形面の剥離が目視で確認できる程度まで磨耗させた（この杵は、後述の比較例１の杵に相当する）。次に、磨耗した杵の先端部を洗浄、乾燥させた後に、平均粒径３０〜２００μｍの微粒子を、杵先のキャビテイに吹き付け、さらに、平均粒径１０〜５０μｍの微粒子を吹き付ける処理を行った。洗浄・乾燥させた後に１０μｍ厚さのクロムメッキを施した。
【００１８】
比較例１：上述の方法で磨耗させた杵（すなわち、微粒子の吹き付け処理前の杵）を用いた。
上記の２つの杵の性能について、先端部の打錠成形面の表面粗さ、打錠成形面の剥離の程度、打錠性能（不良率）、および打錠時の離型性を比較し評価した。結果を以下の表１に示す。
【００１９】
【表１】

【００２０】
表１から明らかなように、比較例１に認められていた金属の剥離や表面の不均一さが、実施例１において著しく改善し、さらに打錠成形性および離型性が大幅に向上していた。本発明の処理を行うことにより、今まで廃棄するしかなかった磨耗した杵についてのリサイクルが可能となることが確認された。
【００２１】
〔実施例２および実施例３〕
実施例２：打錠成形用の杵（ＳＫＤ６１製、直径６．０ｍｍの棒状の先端部に、１０〜１５μｍクロムメッキされた打錠成形用のキャビティ（Ｒ１２）を有する）を磨耗させた後に、この先端部に対し、実施例１と同様の微粒子を吹き付ける処理を行った。次いで、この表面に１０μｍ厚さのクロムメッキを施した。
【００２２】
実施例３：打錠成形用の杵（ＳＫＤ６１製、直径６．０ｍｍの棒状の先端部に、１０〜１５μｍクロムメッキされた打錠成形用のキャビティ（Ｒ１２）を有する）を磨耗させた後に、この先端部に対し、実施例２と同様の処理方法により微粒子の吹きつけ、クロムメッキ加工を行った。さらに、この表面にＰＶＤ処理（イオンプレーティング）を行って表層にＣｒＮを蒸着させ、２〜３μｍのＣｒＮ層を形成させた。
【００２３】
比較例２：上述の杵と同一形状を有する、未使用状態の打錠成形用の杵（ＳＫＤ６１製、直径６．０ｍｍの棒状の先端部に、１０〜１５μｍクロムメッキされた打錠成形用のキャビティ（Ｒ１２）を有する）を用いた。
上記の実施例２、実施例３および比較例２の杵を、後述する打錠成形能評価に供した。
【００２４】
各杵を打錠成形機に取り付けて、炭酸カルシウムを主成分とする錠剤を加工成形する打錠試験を実施し、各杵の打錠成形能を評価した。打錠成形能は、成形不良品が出現するまでの打錠数で表した。評価結果を、図２に示す。
【００２５】
図２から明らかなように、実施例２の杵は比較例２の杵と同等の打錠性能を有していた。また、実施例３の杵は、比較例２および実施例２の杵よりも優れた打錠性能（約１．５倍の打錠数）を有していた。すなわち、本発明の処理により、磨耗した杵を新品同様の性能にまで復元することが可能となり、さらに、ＰＶＤ処理による窒化クロムの表面処理を追加で行うと、杵の使用寿命を初期状態のものよりもより一層延長できることが確認された。
【００２６】
なお、本発明における構成は、以上説明したものに限定されないのは勿論であるり、その趣旨を逸脱しない範囲で種々変形が可能である。
【００２７】
【発明の効果】
本発明の表面処理方法によれば、打錠成形用の杵および臼の打錠成形の低下の原因となる打錠成形面の歪み、金属メッキの剥離、バリ等の異常部位が取り除かれて、より均一な表面が得ることが可能となる。そして、この均一な表面上に、金属被膜の再処理を安定的に施すことで、新品同様の杵および臼を提供できるという効果を奏する。したがって、従来の杵および臼の使用寿命を延長せしめると同時に、今までは廃棄していた杵および臼をリサイクルできるので、廃棄物の減量に大きく貢献できる効果も有する。また、本発明の処理は、杵および臼のボディをそのまま活用しているので、新品のものを製造する場合と比べて原料費や時間を大幅に削減できるというメリットも有する。さらに、本発明の処理によってリサイクルした杵および臼の使用目安が一目で把握できるし、使用限界時期に再度本発明の処理を施せば、杵および臼を半永久的に利用することが可能となるという効果も奏する。
【図面の簡単な説明】
【図１】本発明の一実施例を説明するもので、打錠成形用の杵の側面図である。
【図２】同実施例および本発明の他の実施例における、打錠成形性能を示すグラフである。
【符号の説明】
１　杵
２　打錠成形面[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is intended to improve the durability of punches and dies (including plastic molding dies) used in tableting machines for manufacturing semiconductors, confectionery, medicine, health foods, etc., and to extend the service life. Regarding surface modification. In particular, the present invention relates to a surface modification for recycling a punch and a die for tableting having a worn tableting surface due to use.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, the body of a punch and a die (including a plastic molding die) of a tableting machine for producing semiconductors, confectionery, medicine, health foods, etc. is formed from a material such as SKD steel, and after polishing the surface, Further, it is widely and generally practiced to apply metal plating such as chrome to the concave surface of the tableting portion at the tip of the punch and the surface of the inner wall of the die.
When such punches or dies are repeatedly used in a tableting machine, the above-described concave surface of the tip of the punch and the chrome plating on the inner wall surface of the dies gradually wear, impairing the tableting formability, deformation of the product, and the like. The occurrence of burrs causes a problem that the yield of products is reduced. Further, there is a danger that the chromium plating is finely peeled off by the impact at the time of tableting, and the fragments are mixed into the product. Until now, there has been no method to effectively remove and repair unnecessary chromium plating layers.
[0003]
[Problems to be solved by the invention]
Therefore, the life of the frequently used punches or dies is currently quite short, about 3 to 6 months, and the punches and dies with the above-mentioned inconveniences are discarded as they are without being repaired. Have been replaced. However, from the viewpoints of recent environmental problems and cost reduction, effective means for reducing waste as much as possible, recycling and recycling waste products has been strongly desired.
[0004]
The present invention solves such a problem, makes it possible to recycle punches and dies of a tableting machine that have been discarded, and extends the service life of the punches and dies. The task is to provide.
[0005]
[Means for Solving the Problems]
The present invention is a process for modifying a tableting surface of a punch and / or a die used in a tableting machine, wherein fine particles are mixed with compressed air and sprayed on the tableting surface. This has solved the above problems.
[0006]
Here, "mixing and blowing the fine particles into the compressed air" means a dry blasting process in which the fine particles are jetted at an injection pressure equal to or higher than a certain pressure to collide with a target surface. Can be modified. The effect of the modification by spraying the fine particles depends on the injection pressure and the shape and size of the fine particles to be injected, but here, the collision of the fine particles causes a defect on the tablet forming surface, that is, specifically, tableting. An abnormal site such as distortion, peeling, burr, etc. of the tableting molding surface, which causes a reduction in molding performance, is removed, and fine cracks are enclosed, so that the surface is processed into a more uniform surface than before the treatment. According to this method, the above-described problems of the tablet forming surface are resolved, and the surface layer treatment such as chrome plating can be performed subsequently, so that the service life of the existing punches and dies for tablet forming can be reduced. It will be extended. According to the present invention, the surface roughness of the spray-treated surface is desirably finished to about 1.35 μm or less in Ra, and more desirably in the range of about 0.10 to 0.30 μm.
[0007]
The surface treatment of the present invention is applied to the recycle processing of punches and / or dies, so that punches or dies having significantly worn tableting surfaces, which had previously been forced to be discarded and replaced with new ones, are obtained. Can also be regenerated as new and reused.
[0008]
Further, from the viewpoint of good surface finish and easy handling of the fine particles, the fine particles are preferably fine particles of ore, and the average particle diameter is preferably about 10 to 200 μm. In particular, it is preferable to use two types of fine particles having different average particle sizes separately. Specifically, it is desirable to first perform a spraying process with finer particles having a larger particle size (coarse), and then perform a spraying process with finer particles having a smaller particle size (fine). According to such a method, firstly, the tablet molding surface can be effectively removed by peeling the tablet molding surface or foreign substances caught between burrs by using coarse particles, and the tablet molding surface can be made more uniform by finer particles. Processing becomes possible. The average particle diameter of the coarse particles is preferably about 30 to 200 μm, and the average particle diameter of the fine particles is particularly preferably about 10 to 50 μm.
[0009]
Further, since a metal thin film is further formed on the surface subjected to the treatment of spraying the fine particles, the abrasion resistance and corrosion resistance of the punch and the die are further improved. Examples of the metal thin film include those containing chromium or titanium. Examples of a method for forming a thin film include ordinary plating methods such as vacuum deposition, sputtering, electroplating, and chemical plating. A chromium nitride film formed by a PVD process is particularly preferable.
[0010]
Further, in order to make it possible to see at a glance the degree of wear of the tablet forming surface, it is preferable that the metal thin film is formed by laminating different metals. In such a case, the state in which the uppermost metal thin film is worn and the lower metal thin film is exposed can be visually confirmed, so that the service life of the punch or the die can be accurately and easily grasped. . If the surface modification treatment of the present invention is performed again on the punches and dies that have reached the end of their service life, the punches and dies can be more efficiently recycled.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments for carrying out the present invention will be described.
[0012]
FIG. 1 is a diagram for explaining a tableting punch as one embodiment of the present invention. The punch 1 for tableting is a rod-shaped one that is used by being attached to a tableting machine. The tableting surface 2 at the tip of the punch 1 is provided with a die (also provided in the tableting machine). (Not shown), confectionery, medicine, health foods, semiconductors, etc. are formed from powder or gel. The tablet molding surface 2 is provided with a cavity (dent) corresponding to the shape of the product to be tablet molded. The punch 1 and the body of the die are manufactured from a steel material such as SKD61 from the viewpoint of corrosion resistance, strength and the like, and the surface is subjected to metal plating such as chrome. When such a punch 1 is repeatedly used in a tableting machine to give an impact, the metal plating layer on the tableting surface 2 is gradually deformed, and eventually peeling or cracking occurs, making it impossible to mold the product. It is becoming.
[0013]
The ore fine particles having a particle size of about 10 to 200 μm are sprayed on the tablet forming surface 2 of the worn punch as described above, and blasting is performed. There is no particular limitation on the type of ore. The ore fines are mixed with the compressed air and injected at about 0.1-2.5 bar pressure into the intended cavity. First, the ore fine particles having a coarse particle diameter are sprayed on the tablet forming surface 2 and then the fine particles having a fine particle diameter are sprayed. As a first step, slightly square ore fine particles having an average particle diameter of about 30 to 200 μm are sprayed on the tablet forming surface 2 to roughly remove metal plating in a peeled state and foreign substances sandwiched between irregularities. Subsequently, fine fine particles having an average particle size of about 10 to 50 μm are sprayed on the tableting surface 2 to smooth out unevenness of the surface and finish the surface more uniformly. The degree of the finish depends on the plating condition of the punch before treatment and the degree of wear of the tableting surface, but the surface roughness after treatment is Ra to 0.10 to 0.30 μm. It is particularly preferable for performing the treatment. Next, washing and washing are performed to remove extra fine particles, and a thin film treatment with a metal such as chromium is performed. Thus, the punches that have reached the limit of use due to wear can be recycled to provide punches similar to new ones.
[0014]
It is also desirable to apply a metal nitride coating to impart further durability to the punch and die. In particular, a chromium nitride film formed by PVD treatment (ion plating) is preferable. In addition, when recycled punches and dies are used in a tableting machine, in order to use them safely without exceeding their usage limits, different metals are laminated to form a thin film. Is particularly preferred. For example, a titanium nitride coating layer of about 1 μm is provided as a lower layer, and a chromium nitride coating layer is provided thereon. When the chromium nitride is worn by use, the metallic luster (gold-colored color) unique to titanium nitride is exposed from between the chromium nitride (gray-colored metallic luster), which is a guide for knowing the usage limit. Further, a chromium nitride coating layer may be provided as a lower layer, and a titanium nitride coating layer may be provided as an upper layer.
[0015]
In addition, the above-described processing method performed on a punch is also applied to a tableting die. This makes it possible to greatly extend the service life of the conventional mortar.
[0016]
Next, the present invention will be described in more detail based on examples, but the present invention is not limited by the examples.
[0017]
Example 1: First, a punch is attached to a tableting machine. The punch is made of SKD61, and the tip of a 6.0 mm diameter rod-shaped punch is provided with an inverted bowl-shaped cavity (R = 12.0 mm) for tableting, and its surface is chrome-plated. is there. This punch was repeatedly subjected to tablet processing and molding of a powder containing sodium bioxide as a main component, and was abraded to such an extent that the exfoliation of the tableting surface at the tip could be visually confirmed. 1 punch). Next, after washing and drying the tip portion of the worn punch, fine particles having an average particle size of 30 to 200 μm are sprayed on the cavity of the tip of the punch, and a process of spraying fine particles having an average particle size of 10 to 50 μm was performed. . After washing and drying, a 10 μm thick chrome plating was applied.
[0018]
Comparative Example 1: A punch worn by the above-described method (that is, a punch before spraying fine particles) was used.
The performance of the above two punches was evaluated by comparing the surface roughness of the tablet forming surface at the tip, the degree of peeling of the tablet forming surface, the tableting performance (defective rate), and the releasability during tableting. did. The results are shown in Table 1 below.
[0019]
[Table 1]

[0020]
As is clear from Table 1, the peeling of the metal and the unevenness of the surface observed in Comparative Example 1 were remarkably improved in Example 1, and the tableting moldability and the releasability were significantly improved. Was. It has been confirmed that by performing the treatment of the present invention, it is possible to recycle a worn punch that had to be discarded until now.
[0021]
[Examples 2 and 3]
Example 2: After a tablet-forming punch (manufactured by SKD61, having a rod-shaped tip having a diameter of 6.0 mm and having a chromium-plated cavity (R12) of 10 to 15 µm at the tip thereof) was abraded, The same fine particles as in Example 1 were sprayed on the tip. Next, chromium plating with a thickness of 10 μm was applied to this surface.
[0022]
Example 3: After a tablet-forming punch (made from SKD61, having a rod-shaped tip having a diameter of 6.0 mm and having a chrome-plated cavity (R12) of 10 to 15 µm at the tip thereof) was abraded, Fine particles were sprayed on the tip by the same processing method as in Example 2, and chrome plating was performed. Further, the surface was subjected to PVD treatment (ion plating) to deposit CrN on the surface layer to form a CrN layer having a thickness of 2 to 3 μm.
[0023]
Comparative Example 2: An unused tableting punch having the same shape as the above-mentioned punch (manufactured by SKD61 and having a rod-shaped tip having a diameter of 6.0 mm, and having a chrome-plated tip of 10 to 15 μm for tableting). (With a cavity (R12)).
The punches of Example 2, Example 3, and Comparative Example 2 were subjected to tableting ability evaluation described later.
[0024]
Each punch was attached to a tableting machine, and a tableting test for processing and forming a tablet containing calcium carbonate as a main component was performed, and the tableting ability of each punch was evaluated. The tableting ability was represented by the number of tablets until a defective molding appeared. FIG. 2 shows the evaluation results.
[0025]
As is clear from FIG. 2, the punch of Example 2 had the same tableting performance as the punch of Comparative Example 2. The punch of Example 3 had better tableting performance (about 1.5 times the number of tablets) than the punches of Comparative Example 2 and Example 2. That is, by the treatment of the present invention, a worn punch can be restored to the same performance as a new one. Further, if the surface treatment of chromium nitride by PVD treatment is additionally performed, the service life of the punch is reduced to that of the initial state. It was confirmed that it could be extended even more.
[0026]
It should be noted that the configuration of the present invention is not limited to the configuration described above, and various modifications can be made without departing from the gist of the invention.
[0027]
【The invention's effect】
According to the surface treatment method of the present invention, abnormalities such as distortion of the tableting molding surface, which causes a decrease in tableting molding of punches and dies for tableting and molding, peeling of metal plating, and burrs are removed, A more uniform surface can be obtained. Then, by performing the reprocessing of the metal film stably on the uniform surface, an effect is provided that a punch and a die similar to a new product can be provided. Accordingly, the service life of the conventional punches and dies can be prolonged, and at the same time, the punches and dies which have been discarded can be recycled, which has an effect of greatly contributing to the reduction of waste. Further, since the processing of the present invention utilizes the body of the punch and the die as they are, there is also an advantage that the raw material cost and time can be greatly reduced as compared with the case of manufacturing a new product. Furthermore, it is possible to grasp at a glance the use guide of the punches and dies recycled by the treatment of the present invention, and it is possible to use the punches and dies semi-permanently by performing the treatment of the present invention again at the use limit time. It also has an effect.
[Brief description of the drawings]
FIG. 1 is a side view of a punch for tableting, illustrating an embodiment of the present invention.
FIG. 2 is a graph showing tableting performance in the example and another example of the present invention.
[Explanation of symbols]
1 punch 2 tablet compression molding surface

Claims

A process for modifying a tableting surface of a punch and / or a die for tableting,
A surface treatment method, wherein ore fine particles are mixed with compressed air and sprayed on the tablet forming surface.

The surface treatment method according to claim 1, wherein the method is applied to a recycling process of a punch and / or a die.

The surface treatment method according to claim 1, wherein an average particle diameter of the fine particles is in a range of 10 to 200 μm.

The surface treatment method according to any one of claims 1 to 3, wherein two types of the fine particles having different average particle diameters are separately sprayed.

The surface treatment method according to any one of claims 1 to 4, wherein a metal thin film is further formed on the surface subjected to the treatment of spraying the fine particles.

The surface treatment method according to claim 5, wherein the metal thin film is formed by laminating different metals.

The surface roughness of the tablet forming surface of the punch or die is reduced to 1.35 μm or less in Ra by mixing two types of fine particles having different average particle sizes into compressed air and spraying them separately. Pestle and / or mortar.