JPH0493232A - Manufacture of polytetrafluoroethylene resin molded article - Google Patents
Manufacture of polytetrafluoroethylene resin molded articleInfo
- Publication number
- JPH0493232A JPH0493232A JP21133690A JP21133690A JPH0493232A JP H0493232 A JPH0493232 A JP H0493232A JP 21133690 A JP21133690 A JP 21133690A JP 21133690 A JP21133690 A JP 21133690A JP H0493232 A JPH0493232 A JP H0493232A
- Authority
- JP
- Japan
- Prior art keywords
- ptfe
- baked
- molded article
- melting point
- temperature
- 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
- 229920001343 polytetrafluoroethylene Polymers 0.000 title claims abstract description 50
- 239000004810 polytetrafluoroethylene Substances 0.000 title claims abstract description 50
- 229920005989 resin Polymers 0.000 title claims abstract description 23
- 239000011347 resin Substances 0.000 title claims abstract description 23
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 11
- -1 polytetrafluoroethylene Polymers 0.000 title claims abstract description 11
- 238000002844 melting Methods 0.000 claims abstract description 14
- 230000008018 melting Effects 0.000 claims abstract description 14
- 238000010304 firing Methods 0.000 claims description 20
- 238000000034 method Methods 0.000 abstract description 16
- 238000000354 decomposition reaction Methods 0.000 abstract description 2
- 239000000843 powder Substances 0.000 description 8
- 239000000463 material Substances 0.000 description 7
- 239000012535 impurity Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 3
- 238000000465 moulding Methods 0.000 description 3
- 238000004140 cleaning Methods 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 229920006361 Polyflon Polymers 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 229920002545 silicone oil Polymers 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 238000010558 suspension polymerization method Methods 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
- 238000007666 vacuum forming Methods 0.000 description 1
Landscapes
- Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
Abstract
Description
【発明の詳細な説明】
発明の技術分野
本発明は、極めて平滑な表面を有する成形品を製造でき
るようなポリテトラフルオロエチレン樹脂成形品の製造
方法に関する。DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method for producing a polytetrafluoroethylene resin molded article, which makes it possible to produce a molded article having an extremely smooth surface.
発明の技術的背景
ポリテトラフルオロエチレン（以下ＰＴＦＥということ
がある）などのフッ素樹脂は、耐熱性、耐候性、耐化学
薬品性、離型性、滑り特性、非粘着性、機械的強度など
の点において、他の合成樹脂と比較して、著しく優れた
特性を有しており、この特性を利用して、腐蝕性流体あ
るいは高温流体を扱うパイプライン、タンクあるいは機
械装置などの耐蝕性ライニング材として、または、腐蝕
性流体などを収容するボトルとして広く利用されている
。Technical Background of the Invention Fluororesins such as polytetrafluoroethylene (hereinafter sometimes referred to as PTFE) have properties such as heat resistance, weather resistance, chemical resistance, mold releasability, slip properties, non-stick properties, and mechanical strength. In this respect, it has significantly superior properties compared to other synthetic resins, and this property can be used to create corrosion-resistant lining materials for pipelines, tanks, and mechanical equipment that handle corrosive or high-temperature fluids. It is widely used as a container or as a bottle to contain corrosive fluids.
このようなＰＴＦＥの樹脂成形品を製造する方法には、
ＰＴＦＥ粉末を加熱圧縮して予備成形した後、焼成して
円筒状ＰＴＦＥ樹脂製ブロックを得、このブロックを切
削して得られたシート状物を融点〜３７０℃の温度で再
焼成した後真空成形などを施して目的の成形品を得る方
法、前記円筒状ＰＴＦＥ樹脂製ブロックを切削して目的
形状に形成し同様に融点〜３７０℃の温度で再焼成して
目的の成形品を得る方法、ＰＴＦＥ粉末を金型などで加
圧圧縮して得られた目的形状の未焼成予備成形体を融点
〜３７０℃の温度で焼成して目的の成形品を得る方法な
どがある。The method for manufacturing such PTFE resin molded products includes:
After preforming the PTFE powder by heating and compressing it, it is fired to obtain a cylindrical PTFE resin block, and the sheet-like material obtained by cutting this block is re-fired at a temperature between the melting point and 370°C, and then vacuum-formed. PTFE There is a method of obtaining a desired molded article by compressing a powder under pressure using a mold or the like and firing an unfired preformed body having a desired shape at a temperature of from the melting point to 370°C.
これらの方法において、焼成されたＰＴＦＥ成形見に融
点〜３７０℃の温度で再焼成または焼成を施しているの
は、たとえばＰＴＦＥの結晶化度を下げ、ＰＴＦＥの延
伸性を良くし、加工性の良い優れた特性を有する成形品
を得ることができるからである。In these methods, the fired PTFE molded specimen is re-fired or fired at a temperature between the melting point and 370°C, for example, to lower the crystallinity of PTFE, improve the stretchability of PTFE, and improve workability. This is because a molded product having good and excellent properties can be obtained.
しかしながら、このように融点以上の温度で再焼成また
は焼成されたＰＴＦＥ成形品の表面には、粒状突起物が
生成している。この粒状突起物は、たとえば特願昭６２
−１１８１４１号に開示したように、アンカー作用をな
し、被着体をＰＴＦＥ成形品に良好に接着することがで
きるという利点を有するが、反面、半導体関連に代表さ
れる高純度薬液を給送するパイプラインのライニング材
として、またはこの薬液のボトルとしてＰＴＦＥを使用
した場合には、成形品の表面に生成した粒状突起物間の
空隙に不純物が付着したりして、薬液を汚染する虞れが
あった。また、この不純物を洗浄するにしても、粒状突
起物が邪魔になり、洗浄も困難であるという問題があっ
た。However, granular protrusions are formed on the surface of the PTFE molded product that has been refired or fired at a temperature above the melting point. These granular protrusions are, for example,
As disclosed in No. 118141, it has the advantage of acting as an anchor and adhering the adherend to the PTFE molded product well, but on the other hand, it is difficult to feed high-purity chemicals typically used in semiconductor-related applications. When PTFE is used as a pipeline lining material or as a bottle for this chemical solution, there is a risk that impurities may adhere to the voids between the granular protrusions formed on the surface of the molded product and contaminate the chemical solution. there were. Further, even if this impurity is to be cleaned, there is a problem in that the granular protrusions become an obstacle and cleaning is also difficult.
また、微細な不純物の除去に用いるＰＴＦＥ多孔質多孔
同体に融点から３７０℃の温度で再焼成処理しているた
め、粒状突起物が生成し、不純物の付着、洗浄の問題が
発生する懸念がある。In addition, since the PTFE porous body used to remove minute impurities is re-fired at a temperature of 370°C above its melting point, there is a concern that granular protrusions may be formed, causing impurity adhesion and cleaning problems. .
発明の目的
本発明は、上述した従来技術に伴う問題点を解決しよう
とするものであって、ポリテトラフルオロエチレン樹脂
成形品の焼成時（または再焼成時）に粒状突起物を生成
させず、または−旦生成した粒状突起物を消失させ、極
とて平滑な表面を有する成形品を製造できるポリテトラ
フルオロエチレン樹脂成形品の製造方法を提供すること
を目的としている。OBJECTS OF THE INVENTION The present invention aims to solve the problems associated with the prior art described above, and is aimed at preventing the generation of granular protrusions during firing (or re-firing) of polytetrafluoroethylene resin molded products, Another object of the present invention is to provide a method for producing a polytetrafluoroethylene resin molded article, which allows the production of a molded article having an extremely smooth surface by eliminating the granular protrusions that have already formed.
発明の概要
本発明は、ポリテトラフルオロエチレン樹脂成形品を、
ポリテトラフルオロエチレン樹脂の融点以上４００℃以
下の温度で、５〜５００ｋｇ１／ｃＩＩｆの圧力を加え
ながら焼成することを特徴としている。Summary of the invention The present invention provides a polytetrafluoroethylene resin molded product,
It is characterized by firing at a temperature above the melting point of the polytetrafluoroethylene resin and below 400° C. while applying a pressure of 5 to 500 kg1/cIIf.
本発明では、ＰＴＦＥ粉末を金型などで加熱圧縮して予
備成形した未焼成ＰＴＦＥ樹脂予備成形体、あるいは表
面に粒状突起物が生成された焼成済みＰＴＦ Ｅ樹脂成
形体を、上記条件の下で焼成しており、このようにする
と、粒状突起物を生成せずに焼成することができ、ある
いは−旦生成した粒状突起物を消失することができる。In the present invention, an unfired PTFE resin preform, which is preformed by heating and compressing PTFE powder in a mold, or a fired PTFE resin molding, which has granular protrusions formed on the surface, is processed under the above conditions. By doing so, it is possible to perform the firing without producing granular protrusions, or to eliminate the granular protrusions that have already been produced.
したがって、本発明に係る加熱焼成により、極めて平滑
な表面を有する成形品を得ることができる。Therefore, by heating and firing according to the present invention, a molded article having an extremely smooth surface can be obtained.
発明の詳細な説明
以下、ライニング材またはボトルなどのＰＴＦＥ樹脂成
形品を製造する工程を説明しながら、本発明をより具体
的に説明する。DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in more detail below while explaining the process of manufacturing a PTFE resin molded product such as a lining material or a bottle.
ライニング材またはボトルなどのＰＴＦＥ樹脂成形品の
製造方法には、以下のような３通りの方法がある。There are three methods for manufacturing PTFE resin molded products such as lining materials or bottles, as described below.
第１の方法は、ＰＴＦＥ粉末を加熱圧縮して予備成形し
その後焼成して円筒状ＰＴＦＥ樹脂製ブロックを得、こ
のブロックを切削して得られたシート状物を再焼成した
後真空成形などを施して目的の成形品を得る方法であり
、たとえばライニング材を製造する際に採用される。The first method is to heat-compress PTFE powder, pre-form it, and then bake it to obtain a cylindrical PTFE resin block, cut this block, re-fire the resulting sheet-like material, and then perform vacuum forming, etc. This is a method in which a desired molded product is obtained by applying a molded product, and is employed, for example, when manufacturing a lining material.
第２の方法は、前記円筒状ＰＴＦＥ樹脂製ブロックを切
削して目的形状に形成し再焼成処理して目的の成形品を
得る方法である。The second method is to cut the cylindrical PTFE resin block to form the desired shape and re-fire it to obtain the desired molded product.
第３の方法は、ＰＴＦＥ粉末を金型などで加圧圧縮して
得られた目的形状の未焼成予備成形体を焼成し、目的の
成形品を得る方法であり、たとえばボトルを製造する際
に採用される。The third method is to pressurize and compress PTFE powder using a mold or the like, and then sinter the unfired preform of the desired shape to obtain the desired molded product. For example, when manufacturing bottles, Adopted.
第１．第２の方法で用いる円筒状ブロックは、円筒金型
内にＰＴＦＥ粉末を充填した後、約１００〜３５０ｋｇ
１／ｃｎｆの圧力で予備成形し、次いで、ＰＴＦＨの融
点以上の温度（通常３４０℃〜３７０℃）で焼成した後
冷却することにより得られる。第１の方法では、このブ
ロックを切削加工して、シート状などの成形品を形成す
る。円筒状ブロックの表面には、わずかに粒状突起物が
生成しているが、表層内部には、この粒状突起物は生成
していないので、切削されたシートの表面には粒状突起
物は現われていない。1st. The cylindrical block used in the second method weighs approximately 100 to 350 kg after filling the PTFE powder into the cylindrical mold.
It is obtained by preforming at a pressure of 1/cnf, then firing at a temperature higher than the melting point of PTFH (usually 340°C to 370°C), and then cooling. In the first method, this block is cut to form a molded product such as a sheet. Although a few granular protrusions are generated on the surface of the cylindrical block, these granular protrusions are not generated inside the surface layer, so no granular protrusions appear on the surface of the cut sheet. do not have.
第１．第２の方法では、シート状物、目的形状の成形品
を３４０℃〜３７０℃で再度焼成（再焼成処理）する一
方、第３の方法では、未焼成予備成形体を同様の温度で
焼成する。1st. In the second method, the sheet-like object or molded article in the desired shape is fired again at 340°C to 370°C (re-firing treatment), while in the third method, the unfired preform is fired at the same temperature. .
第１．第２の方法のように再焼成する理由は、たとえば
成形品の結晶化度をコントロールし、加工性を良くした
り、機械的特性を向上する等、目的に応じた処理方法が
必要とされるからである。1st. The reason for re-firing as in the second method is that a treatment method is required depending on the purpose, such as controlling the crystallinity of the molded product, improving workability, and improving mechanical properties. It is from.
しかし、従来は、この再焼成あるいは焼成時に、粒状突
起物がＰＴＦＥ成形品の表面に生成していた。However, conventionally, granular protrusions were generated on the surface of the PTFE molded product during this re-firing or firing.
この粒状突起物は、ＰＴＦＥを構成する最小の粒子であ
って、Ｊｏｕｒｎａｌ Ｏｊ Ａｐｐｌｉｅｄ Ｐｏｌ
ｙｍｃｒＳｅｉｅｎｃｐ Ｖｏｌ、 ３７２８９−２
９０６（１９８９） に記載のリボン状 （＋１ｂｂｏ
ｎｌｉｋ）粒子であると考えられており、この粒状突起
物が生成するのは、ＰＴＦＥ粉末内に折り畳まれたリボ
ン状粒子間の空隙部が予備成形圧によって密になるよう
に変形を受け、次いで焼成すると、変形を受けていたリ
ボン状粒子が成形品表面に突出し、これが粒状突起物と
なって現われるものと考えられている。These granular protrusions are the smallest particles constituting PTFE, and are reported in Journal Oj Applied Pol
ymcrSeiencp Vol, 37289-2
906 (1989)
These granular protrusions are generated because the voids between the folded ribbon-like particles in the PTFE powder are deformed to become dense by preforming pressure, and then It is believed that upon firing, the ribbon-like particles that have undergone deformation protrude onto the surface of the molded product, and these appear as granular protrusions.
本発明では、ＰＴＦＥ樹脂の融点（３２７℃）以上４０
０℃以下の温度で、５〜５００ｋｇ１／ａｌの圧力を加
えながら、ＰＴＦＥ樹脂成形品（すなわち、シート状物
、未焼成予備成形体など）に再焼成あるいは焼成を施し
ている。または３４０℃〜３７０℃で再焼成・焼成した
後玉８この条件で圧力を加えながら焼成している。この
ようにすると、粒状突起物を生成せずに焼成することが
でき、あるいは−旦生成した粒状突起物を消失すること
ができ、その結果、極めて平滑な表面を有する成形品を
得ることができる。In the present invention, the melting point of PTFE resin (327°C) or higher is 40°C.
A PTFE resin molded product (i.e., a sheet-like product, an unfired preform, etc.) is subjected to re-firing or firing at a temperature of 0° C. or lower while applying a pressure of 5 to 500 kg1/al. Alternatively, after re-firing and firing at 340°C to 370°C, the ball 8 is fired under these conditions while applying pressure. In this way, it is possible to perform firing without producing granular protrusions, or to eliminate the granular protrusions that have been formed, and as a result, it is possible to obtain a molded product with an extremely smooth surface. .
圧力５〜５００ｋｇ１／ｃｄの条件にしたツバ、５ｋｇ
１／ａｌ以下であると、粒状突起物が若干生成すること
があるからであり、５００ｋｇ１／ａ！以上であると、
１９５２年 Ｐ、 Ｌ、 ＭｃＧ＋ｅ！ｒｉ：よッテ提
案すれた次式
％式％）
の関係式から、ＰＴＦＥの融点が４０４℃となり、ＰＴ
ＦＥの分解温度以上に融点が上がるため、好ましくない
からである。Brim under pressure 5-500kg1/cd, 5kg
This is because if it is less than 1/al, some granular protrusions may be generated, and 500kg1/al! If it is above,
1952 P, L, McG+e! ri: From the following equation proposed by Yotte, the melting point of PTFE is 404°C, and PTFE
This is because the melting point rises above the decomposition temperature of FE, which is not preferable.
なお、本発明は、上述した具体的説明に限定されるもの
ではな（、種々改変可能である。たとえば、本発明に係
る加圧焼成により粒状突起物が生成しないだけでなく、
その他の凹凸も生成することがない。Note that the present invention is not limited to the above-mentioned specific explanation (and can be modified in various ways. For example, the pressure firing according to the present invention not only does not generate granular protrusions,
No other unevenness is generated.
発明の効果
以上述へたように、本発明では、ＰＴＦＥ成形品を上記
所定の条件で加圧焼成することにより、粒状突起物を生
成せずに焼成することができ、あるいは−旦生成した粒
状突起物を消失することができ、その結果、極めて平滑
な表面を有する成形品を得ることができる。Effects of the Invention As described above, in the present invention, by pressurizing and firing a PTFE molded product under the above-mentioned predetermined conditions, the PTFE molded product can be fired without producing granular protrusions, or - Protrusions can be eliminated, and as a result, a molded article with an extremely smooth surface can be obtained.
（実施例）
以下、本発明を実施例により説明するが、本発明はこれ
らの実施例に限定されるものではない。(Examples) The present invention will be described below with reference to Examples, but the present invention is not limited to these Examples.
実施例１
懸濁重合法によって得られた平均粒子径２５μｍのＰＴ
ＦＥ成形用粉末（ポリフロンＭ１２ダイキン工業■製）
を円筒金型中で成形圧１５０ｋｇ１／ｃＩｌで予備成形
した後、この予備成形体を３６５℃で焼成しブロック状
の完全に焼成されたＰＴＦＥ成形品を作成した。このＰ
ＴＦ Ｅ成形品の表面には、粒状突起物が生成していた
。Example 1 PT with an average particle diameter of 25 μm obtained by suspension polymerization method
FE molding powder (Polyflon M12 manufactured by Daikin Industries)
was preformed in a cylindrical mold at a molding pressure of 150 kg1/cIl, and then the preform was fired at 365°C to produce a block-shaped completely fired PTFE molded product. This P
Granular protrusions were generated on the surface of the TFE molded product.
次いで、この粒状突起物が生成しているＰＴＦＥ成形品
をＱ、 １ｍｍの肉厚に切削し、３６５’Ｃの温度で
、３０ｋｇ１／ａｌの圧力を加えながら焼成した。その
結果、粒状突起物は消失していた。Next, the PTFE molded product in which the granular protrusions were formed was cut to a thickness of 1 mm, and fired at a temperature of 365'C while applying a pressure of 30 kg1/al. As a result, the granular protrusions had disappeared.
実施例２
表面に粒状突起物が生成された、実施例１で得られたブ
ロック状ＰＴＦＥ成形品を、３７０℃のシリコンオイル
中で２００ｋｇ１／ｃｆｆｌ、保持時間３０分にて加圧
焼成したところ、ブロック状ＰＴＦＥ成形品表面に生成
されていた粒状突起物は消失し、表面の平滑なＰＴＦＥ
成形品が出来た。Example 2 The block-shaped PTFE molded product obtained in Example 1, in which granular protrusions were generated on the surface, was pressure-sintered in silicone oil at 370° C. at 200 kg1/cffl for a holding time of 30 minutes. The granular protrusions that had been generated on the surface of the block-shaped PTFE molded product disappeared, and the PTFE surface became smooth.
The molded product was completed.
Claims (1)
フルオロエチレン樹脂の融点以上４００℃以下の温度で
、５〜５００ｋｇｆ／ｃｍ＾２の圧力を加えながら焼成
することを特徴とするポリテトラフルオロエチレン樹脂
成形品の製造方法。A polytetrafluoroethylene resin molded product characterized by firing the polytetrafluoroethylene resin molded product at a temperature above the melting point of the polytetrafluoroethylene resin and below 400°C while applying a pressure of 5 to 500 kgf/cm^2. manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21133690A JPH0493232A (en) | 1990-08-08 | 1990-08-08 | Manufacture of polytetrafluoroethylene resin molded article |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21133690A JPH0493232A (en) | 1990-08-08 | 1990-08-08 | Manufacture of polytetrafluoroethylene resin molded article |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0493232A true JPH0493232A (en) | 1992-03-26 |
Family
ID=16604273
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21133690A Pending JPH0493232A (en) | 1990-08-08 | 1990-08-08 | Manufacture of polytetrafluoroethylene resin molded article |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0493232A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011140147A (en) * | 2010-01-06 | 2011-07-21 | Shin Etsu Handotai Co Ltd | Method for manufacturing fluororesin molded object, resin container for analysis and element analytical method |
| JP2012514549A (en) * | 2009-01-09 | 2012-06-28 | ニンボ スーパーブライト テクノロジー カンパニー リミテッド | Seamless edge sealing method of fluororesin coating |
-
1990
- 1990-08-08 JP JP21133690A patent/JPH0493232A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012514549A (en) * | 2009-01-09 | 2012-06-28 | ニンボ スーパーブライト テクノロジー カンパニー リミテッド | Seamless edge sealing method of fluororesin coating |
| JP2011140147A (en) * | 2010-01-06 | 2011-07-21 | Shin Etsu Handotai Co Ltd | Method for manufacturing fluororesin molded object, resin container for analysis and element analytical method |
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