KR101065966B1 - Molding, diaphragm valve, diaphragm pump and method for producing the molding - Google Patents

Abstract

An object of this invention is to provide the molded object of polytetrafluoroethylene resin which hardly adheres and stays in a fluid, and is easy to wash | clean, and does not generate pinhole or a crack, and its manufacturing method.

The present invention is a molded article of polytetrafluoroethylene resin, wherein the molded article has a heat fluidized layer on part or all of its surface layers, and the surface having the heat fluidized layer has a surface roughness of Ra 0.2 µm or less and Ry 2.0 µm or less. It is a molded object characterized by the above-mentioned.

Polytetrafluoroethylene resin, skyve mark, heat fluidized bed, surface roughness

Description

Manufacturing method of molded body, diaphragm valve, diaphragm pump and molded body {MOLDING, DIAPHRAGM VALVE, DIAPHRAGM PUMP AND METHOD FOR PRODUCING THE MOLDING}

The present invention relates to a molded article and a method for producing the same.

Polytetrafluoroethylene [PTFE] molded bodies are used in valves, packings, valve bodies and the like due to their excellent chemical resistance, heat resistance and non-tackiness. In recent years, there has been a demand for reducing the adhesion identity of the fluid to the PTFE molded body and improving the cleanability.

In particular, a diaphragm valve or the like has problems such as stagnant particles on the surface of the molded body, the valve body is bent and the stagnant particles are buried in the molded body, and the starting point reaches the pinhole.

As a method for producing a PTFE molded body, a prebaking method of firing a preform obtained in compression molding, heating the preform molded preform in a mold under heating under pressureless until the PTFE is melted, and then the furnace is kept in a molten state. The hot coining method which removes from every metal mold | die from a metal mold | die, keeps it under pressure again as it is in a molten state, and water-cools is known.

In the case of the prebaking method, it is proposed to reduce the particle size of the raw material PTFE as a means of reducing the surface roughness of the PTFE molded body (see Patent Document 1, for example). However, the surface roughness of the molded product is limited to Ra only 0.7 m.

Moreover, the manufacturing method of the fluororesin diaphragm which mounts the fired body obtained by the prebaking to a secondary metal mold | die, heat-processes, and hot presses after that is proposed (for example, refer patent document 2). However, in this manufacturing method, it is necessary to heat the whole fired body for every metal mold | die.

When molding by the hot coining method, the surface roughness of the molded body can be reduced by reducing the surface roughness of the mold surface. However, since the hot coining method is difficult to uniformly fill the raw material powder, there is a drawback that the thin molded body cannot be stably made and the productivity is insufficient.

Moreover, although the surface roughness of a molded object can be made small to some extent by machining (cutting) a molded object surface, there exists a problem that sufficient surface roughness cannot be obtained and unevenness called a skive mark (cutting mark) remains.

[Patent Document 1] International Publication No. 03/35724 Pamphlet

[Patent Document 2] Japanese Patent Application Laid-open No. Hei 5-10444

An object of the present invention is to provide a molded article of a polytetrafluoroethylene resin and a method for producing the same, in which particles in a fluid are hardly adhered and retained, are easy to clean, and do not generate pinholes or cracks.

This invention is a molded object of polytetrafluoroethylene resin, The said molded object has a heat fluidized layer in the surface layer of one part or all part, The surface which has the said heat fluidized layer has surface roughness of Ra 0.2 micrometer or less and Ry 2.0 micrometer or less. It is a molded object characterized by the above-mentioned.

The diaphragm valve which has a diaphragm provided with the valve seat formed in the valve main body, and the diaphragm valve film which is press-contacted or spaced apart from the said valve seat, The said diaphragm valve film is the said diaphragm valve, It is characterized by the above-mentioned.

The diaphragm pump which delivers a fluid by the reciprocating motion of a diaphragm valve film is a diaphragm pump characterized by the said diaphragm valve film being said molded object.

The present invention provides a process for obtaining a fired body by preforming and firing polytetrafluoroethylene powder, heating a mold surface of a mold having a surface roughness of Ra 0.2 μm or less and Ry 1.5 μm or less, at least 330 ° C., and the mold. And a step of treating a part or all of the surface of the fired body at a surface pressure of 0.2 MPa or more by a surface, the surface roughness of the surface having the heat-fluid layer in part or all of the surface layer and having the heat-fluid layer is Ra It is a manufacturing method of the molded object characterized by manufacturing the molded object of polytetrafluoroethylene resin of 0.2 micrometer or less and Ry 2.0 micrometer or less.

The present invention will be described in detail below.

The molded article of the polytetrafluoroethylene [PTFE] resin of the present invention has a heat fluidized layer in part or all of the surface layers of the surface, and the surface having the heat fluidized layer has a surface roughness of Ra 0.2 µm or less and Ry 2.0 µm or less. It is characterized by. As described above, the molded article of the present invention has a heat fluidized layer, and because of its small surface roughness, it is difficult to oscillate, hardly adhering and retaining particles in the fluid, and easy to clean, so that no pinholes or cracks are generated. It is effective.

The said thermal fluidized layer means the layer of resin which changed the crystal state by heating. In the surface of the molded object of this invention, the heat fluidized layer is formed in the surface layer in the surface processed by the metal mold surface which has specific surface roughness and surface temperature. The heat fluidized layer can be distinguished from other layers in the molded body by observing with a polarizing microscope.

The thermal fluidized bed has a low degree of crystallinity compared to other layers in the molded body. In particular, when the molded article of the present invention is obtained by cutting from a fired body to be described later, the surface before processing of the molded product reflects the crystal state inside the fired body. The inside of the fired body is in a state where the degree of crystallinity is relatively high even though the entire fired body is quenched without following the change in the crystal state of the fired body surface. By treating the molded body with the surface having such a high crystallinity before the treatment with a mold surface having a specific surface roughness and surface temperature, only the surface of the molded body is heat-treated in a short time. Degrades.

The heat fluidized bed may be said to have a different thermal history than layers other than the heat fluidized bed inside the molded body. That is, the thermal fluidized bed has one more heat history than layers other than the thermal fluidized bed.

Since the heat fluidized bed does not contain minute pores or grain boundaries, cracks and pinholes are less likely to occur. It is preferable to form the said heat fluidized layer so that it may become thicker than the depth of the cutting trace formed by a mechanical (cutting) process from the surface excellent in surface smoothness.

In the molded article of the present invention, the surface having the thermal fluidized layer, that is, the surface treated by the mold surface of the mold, may be any one surface or any plural surfaces, not the entire surface of the molded article, but at least the fluid It is preferred that it has been treated to have a thermal fluidized bed for the contacting surface. In addition, in consideration of production efficiency and production cost, it is preferable that only the necessary surface is processed, not the entire surface of the molded body.

Since the molded object of this invention does not need to process the whole surface of a molded object, it is advantageous in production efficiency and production cost compared with the method of heating the whole molded object. Moreover, since the molded object of this invention only needs to exist only in a surface layer, a heat fluidized layer can fully exhibit the effect of this invention even if it is a thick molded object.

The surface roughness is Ra 0.2 µm or less and Ry 2.0 µm or less. Since the molded article of the present invention has such a small surface roughness, particles and the like in the fluid hardly adhere and remain, and the occurrence of pinholes and cracks due to the adhered particles is reduced.

It is preferable that Ry is 1.5 micrometers or less.

The said surface roughness Ra is a value which averages and computes the measured value obtained by repeating the measurement of 5 points | pieces of measurement three times based on JIS B0601-1994 using the surface roughness measuring instrument (SURFTEST SV-600 by Mitutoyo). Ry is the maximum value of the measured value obtained by the said measurement.

Even if the surface roughness of the molded object of this invention is compared with the surface roughness obtained by machining (cutting), it is small. The surface roughness achieved by machining (cutting) is limited to Ra 0.3 µm and exceeds Ry 2.0 µm. Thus, since the molded object of this invention has a heat fluidized layer in a surface layer, and surface roughness is small, it can reduce the generation | occurrence | production and crack generation from the cutting surface at the time of bending compared with the machined (cutting) molded object.

The machining of the fired body before treatment by the mold surface of the mold is not limited at all. Since the molded article of the present invention can be formed into a desired shape by machining, and then processed by the mold surface, the surface roughness is small even though the shape is not limited compared to a molded article having a small surface roughness by directly molding the resin powder. It is advantageous in that. The fired body is obtained by preforming and firing PTFE powder.

In the molded article of the present invention, a part or all of the surface is treated with a surface pressure of 0.2 MPa or more by the mold surface of the mold, and the surface of the mold has a surface roughness of Ra 0.2 µm or less, Ry 1.5 µm or less, and a surface temperature of 330 ° C or more. to be. Since the molded article of the present invention is a part or all of the surface treated by a mold surface having a specific surface roughness and surface temperature, the sky observed on the surface of the molded article machined with a heat fluidized layer and a very small surface roughness and very small surface roughness. It does not have a mark.

Although the above-mentioned skive marks cause adhesion retention of particles contained in the fluid, since there is no skive mark on the surface of the molded body of the present invention, the adhesion retention property is significantly smaller than that of a machined (cut) molded body.

The process by the said mold surface can be performed by heating the metal mold surface of the metal mold | die which has a specific surface roughness to 330 degreeC or more, and making the heated metal surface contact the surface of a molded object by specific surface pressure.

The surface pressure is 0.2 MPa or more. If the surface pressure is less than 0.2 MPa, it is difficult to sufficiently smooth the surface of the molded body. Although the upper limit of the said surface pressure is not specifically limited, It is preferable that it is 30 Mpa.

The surface temperature of the mold surface is 330 ° C �� phase. If surface temperature is less than 330 degreeC, a heat fluidized layer cannot be formed. In addition, the molded body surface is not sufficiently melted, and it is difficult to sufficiently smooth the molded body surface. Although the upper limit of the surface temperature of the said mold surface is not specifically limited, It is preferable that it is 400 degreeC.

The surface roughness of the said mold surface is Ra 0.2 micrometer or less and Ry 1.5 micrometer or less. When Ra exceeds 0.2 mu m or Ry exceeds 1.5 mu m, it is difficult to sufficiently smooth the molded body surface. It is preferable that said Ra is 0.1 micrometer or less. Moreover, it is preferable that Ry is 1.2 micrometers or less.

The PTFE resin in the molded article of the present invention may be made of a homopolymer [TFE homopolymer] of tetrafluoroethylene [TFE] or may be made of modified polytetrafluoroethylene [modified PTFE].

It is preferable that the said PTFE resin is a modified PTFE resin which consists of modified PTFE from the point which is easy to shape | mold and is excellent in the mechanical strength, such as creep resistance, with low melt viscosity.

The modified PTFE is a copolymer of TFE and a trace monomer other than TFE, and means that it is non-melt processable.

As said trace monomer, For example, Fluoroolefin, such as hexafluoropropylene [HFP] and chloro trifluoroethylene [CTFE]; Fluoro (alkyl vinyl ether); Fluorodioxoles; Perfluoroalkylethylene; ω-hydroperfluoroolefin etc. are mentioned.

As said fluoro (alkyl vinyl ether), the perfluoro (alkyl vinyl ether) [PAVE] which has a perfluoroalkyl group of C1-C6 is mentioned, for example.

As said PAVE, perfluoro (methyl vinyl ether) [PMVE], perfluoro (ethyl vinyl ether) [PEVE], perfluoro (propyl vinyl ether) [PPVE], perfluoro (butyl vinyl ether, for example) ), And the like.

The PAVE is preferably PPVE, PEVE or PMVE, and more preferably PPVE from the standpoint of thermal stability.

In the modified PTFE, the minor monomer may be one kind or two or more kinds.

In the said modified PTFE, the content rate which occupies for all the monomer units of the trace monomer unit derived from the said trace monomer is the range of 2 mol% or less normally.

In this specification, "the content rate (mol%) of the trace monomer unit which occupies for the whole monomeric unit" "means the said monomer which occupies the monomer which the said" whole monomeric unit "originates, ie, the monomer whole quantity which comprised modified PTFE. It means the mole fraction (mol%) of the trace monomer from which a trace monomer unit originates.

In this specification, the said trace monomer unit is a value obtained by performing infrared spectroscopic analysis.

In addition to the PTFE resin, the molded article of the present invention may contain a thermoplastic resin having hot melt processability from 0.5 to 30% by mass of the polytetrafluoroethylene resin.

The thermoplastic resin is not particularly limited as long as it has hot melt processability, but is preferably a fluororesin capable of hot melt processing, and the fluororesin is, for example, a tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer [PFA]. And tetrafluoroethylene / hexafluoropropylene copolymer [FEP].

The molded article of the present invention comprises the steps of obtaining a fired body by preforming and firing the PTFE powder, heating the mold surface of a mold having a surface roughness of Ra 0.2 μm or less and Ry 1.5 μm or less to 330 ° C. or higher, and the die surface. It can manufacture suitably by the manufacturing method containing the process of processing one part or all of the surface of the said fired body by surface pressure 0.2 Mpa or more.

The manufacturing method is excellent in production efficiency and production cost since only one desired surface of the fired body is processed after firing once to obtain a fired body. Moreover, after obtaining a fired body, you may machine (cut) before surface treatment, In this case, there is no restriction | limiting in the shape of a molded object, It is advantageous at the point which a skive mark disappears.

It is preferable that the said PTFE powder is a TFE homopolymer obtained by suspension polymerization or emulsion polymerization, or the powder of the said modified PTFE, It is more preferable to obtain by suspension polymerization from the point which can prepare PTFE powder with a small average particle diameter. Do. PTFE powder with a small average particle diameter is preferable at the point which can obtain the molded object with few voids. The suspension polymerization and emulsion polymerization can be carried out by a conventionally known method.

The PTFE powder may be either powder itself obtained by drying from a polymerization reaction solution obtained after suspension polymerization or emulsion polymerization, fine powder obtained by appropriately pulverizing the powder, or granulated powder or fine powder.

Although the said PTFE powder may consist only of PTFE powder, you may mix | blend additives, such as a coloring agent and an antistatic agent, in the range which does not impair the property of PTFE powder.

? "Compression molding is mentioned as said preforming. It is preferable to perform the said compression molding under the pressure of 0.1 Mpa-100 Mpa. The minimum with more preferable said pressure is 1 Mpa, and a more preferable upper limit is 80 Mpa.

The firing may be carried out by putting the preform obtained by the preforming into a firing furnace and raising the firing temperature from room temperature to a firing temperature at a constant rate, and then heating the preform at a firing temperature described below. It can also be performed by putting in a kiln.

Although the said baking is based also on the thickness of a preform, baking time, etc., it is preferable to carry out by heating at the temperature of 345-400 degreeC. The minimum with said more preferable baking temperature is 360 degreeC, and a more preferable upper limit is 390 degreeC.

The fired body may have any shape such as a plate shape, a disc, a cylinder, a cylinder, and the thickness is preferably 0.1 μm to 30 mm.

Since the molded article of the present invention is excellent in mechanical properties, particularly flex resistance and creep resistance, for example, molded articles requiring bend resistance such as bellows, diaphragms, hoses, piston rings, butterfly valves, etc .; It can be set as the molded object which requires creep resistance, such as a ball valve seat, a packing, a gasket, a piston ring, a bellows, a diaphragm, and a butterfly valve seat. Moreover, it can apply to various uses, such as a film for electrical insulation, a release film, and a film for lapping, using a thing with few voids and grain boundaries.

The molded article of the present invention can be suitably used as a seat of a diaphragm valve, and can be suitably used as a valve film of a diaphragm valve or a valve film of a diaphragm pump. When using the molded object of this invention as a valve film of a diaphragm valve or a valve film of a diaphragm pump, it is preferable that the surface which has a heat fluidized layer is a liquid contact side. Since the molded object of the present invention has a surface having a heat fluidized layer on the liquid-contacting side, the amount of oscillation is small and the particles in the fluid can hardly exhibit adhesion.

The diaphragm valve membrane may be a valve membrane having a liquid contact membrane portion, a sealing portion (valve seat pressing portion), and an attachment portion, or may be a sheet-shaped valve membrane. The diaphragm valve membrane having the liquid contact membrane portion, the seal portion and the attachment portion can be suitably used for a diaphragm valve. In addition, the sheet-shaped diaphragm valve membrane can be used suitably for a diaphragm pump.

The present invention is a diaphragm valve having a valve seat formed in a valve body and a diaphragm provided with a diaphragm valve film which is press-contacted or spaced from the valve seat, wherein the diaphragm valve film is also a diaphragm valve of which is the molded body. Since the diaphragm valve of this invention uses the molded object of this invention for the contact surface of a diaphragm, it is possible to greatly reduce the amount of oscillation.

The diaphragm valve of this invention can be used suitably for the valve provided in the CMP slurry supply piping of a semiconductor manufacturing plant.

The diaphragm pump which delivers a fluid by the reciprocating motion of a diaphragm valve film | membrane WHEREIN: The said diaphragm valve film | membrane is also the diaphragm pump which is the said molded object. Since the diaphragm pump of this invention uses the molded object of this invention for the contact surface of a diaphragm valve film | membrane, an amount of oscillation can be reduced significantly.

Since the molded article of the present invention is composed of the above-described configuration, it is difficult to oscillate, particles in the fluid, etc. are hard to adhere and stay, easy to clean, and there is no occurrence of pinholes or cracks due to the retention particles.

The manufacturing method of the molded object of this invention can obtain the above-mentioned "form", and is excellent in production efficiency or a production cost.

Although an Example and a comparative example are shown to the following and this invention is demonstrated concretely, this invention is not limited to these Examples and a comparative example.

Each evaluation in an Example and a comparative example was performed by the following method.

Thickness of the thermal fluidized bed

Using a Nikon polarization microscope (Model No .: OPTIPHOT2-POL) equipped with a Victor color video head (Model No .: TK1283), the thickness of the thermal fluidized layer of the sheet sliced to 100 μm, fixed to the glass preparat was measured. .

Surface Roughness Ra

Surface roughness Ra used the surface roughness measuring instrument (SURFTEST SV-600 by Mitutoyo), and made the average value of the measured value obtained by repeating the measurement of 5 points | pieces three times based on JIS B0601-1994 as Ra.

Surface Roughness Ry

Using the surface roughness Ry and the surface roughness measuring instrument (SURFTEST SV-600 by Mitutoyo), the maximum value of the measured value obtained by repeating the measurement of 5 measurement scores three times according to JIS B0601-1994 was made Ry.

Contact angle

It was measured using a fully automatic contact angle meter (model number: DM700) manufactured by Hyuphwa Interface Science.

[First Embodiment]

200 g of a modified PTFE powder (trade name: New Polypropylene PTFE M-731, manufactured by Daikin Kogyo Co., Ltd.) was introduced into a compression molding die having a mold inner diameter of 50 mm and a mold length of 500 mm, and pressurized to 29.4 MPa at room temperature. , Was taken out from the mold. Subsequently, the obtained preform was heated to 370 ° C. at a rate of 50 ° C./hour in an electric furnace, and then calcined at 370 ° C., and lowered to room temperature at a rate of 50 ° C./hour in an electric furnace to obtain a modified PTFE fired body. Further, the modified PTFE fired body was cut to produce a diaphragm valve membrane (sheet) of a modified PTFE fired body having a diameter of about 47 mm and a thickness of 0.5 mm. The surface roughness of the valve film after cutting was Ra 0.43 µm and Ry 2.71 µm.

The surface roughness of the metal mold in contact with the surface of the valve film on the side to be treated was adjusted to Ra 0.10 µm and Ry 1.19 µm. Only the mold having the mold surface in contact with the surface of the valve membrane was heated so as to have a surface temperature of 360 ° C., and the mold surface was pressed against the valve membrane at a surface pressure of 0.3 MPa for 90 seconds to obtain a treated valve membrane 1.

The obtained valve membrane 1 was sliced to a thickness of 100 μm at right angles to the heating surface using a microtome (Microtome manufactured by MICROM GmbH (Model No .: HM330)) and a dedicated cutter (S22Type), and observed with a polarizing microscope to obtain a thermal fluidized bed. The thickness was measured. The surface roughness of the heating surface and the contact angle of the heating surface were measured with a surface roughness measuring instrument. The results are shown in Table 1. In addition, the observation photograph by a polarization microscope is shown in FIG.

The obtained valve membrane 1 was stirred in a slurry liquid (SEMIS-SPERSE 25-E manufactured by Nippon Cabot / Microelectronics) for 6 hours, and then the slurry droplets with which the valve membrane was taken out were removed and air-dried for 1 minute. Next, 50 ml of pure water was flowed to the slurry attachment part using the dropper, and the attached water was removed and observed with a video microscope (Giance Digital Microscope VHX-900) and photographed. The photograph taken is shown in FIG.

[Example 2 to Example 4, Comparative Example 2 to Example 3]

The valve membrane processed similarly to Example 1 was obtained except having changed surface temperature and surface pressure of the metal mold surface as Table 1. The results are shown in Table 1. Moreover, the observation photograph by a polarization microscope is shown to FIG. 2-FIG. 4, FIG. 6, FIG.

[First Comparative Example]

The thickness, surface roughness, and contact angle of the heat fluidized layer were measured for the valve film after cutting obtained in the first example. The results are shown in Table 1. In addition, the observation photograph by a polarization microscope is shown in FIG. In addition, the valve film after cutting was immersed in the slurry liquid in the same manner as in the first embodiment, and the surface was photographed by a video microscope. The photograph taken is shown in FIG.

Fourth Comparative Example

The valve membrane processed similarly to Example 1 was obtained except having changed the surface temperature and surface pressure of the metal mold | die surface as Table 1, and having performed the process by the metal mold | die surface for 10 minutes. By the process by the metal mold | die surface, the whole valve film was melted and the shape was deformed. The results are shown in Table 1.

[Example 5, Example 6 and Example 8]

The valve membrane processed similarly to Example 1 was obtained except having changed the surface temperature and surface pressure of the metal mold | die surface as Table 1, and not measuring the thickness of a thermal fluidized bed. The results are shown in Table 1.

[Example 7, Comparative Examples 5 to 6]

The valve membrane processed similarly to Example 1 was obtained except having changed surface temperature and surface pressure of the metal mold surface as Table 1. The results are shown in Table 1.

Seventh Comparative Example

The cut valve film (Ra 0.43 micrometer, Ry 2.71 micrometer) obtained in the 1st Example was put into the electric furnace, and it heated at 350 degreeC for 90 second. The entire valve membrane was melted and the shape was deformed. Various physical properties of the obtained valve membrane were measured in the same manner as in the first embodiment. The results are shown in Table 1.

* 1: The whole valve film was melted and the shape was deformed.

From the results of the first to eighth examples, it can be seen that a molded article having a surface having a small surface roughness can be obtained when the surface temperature of the mold is at least 330 ° C and the surface pressure of the treatment by the mold surface is at least 0.2 MPa. Could. From the results of the fourth comparative example, even if the surface temperature of the mold is 330 ° C. or more, if the surface pressure of the treatment by the mold surface is 0 MPa, the entire valve film is melted, and a heat fluidized layer cannot be obtained. I could not see. From the results of the seventh comparative example, it was found that when the heating was performed other than the melting point of the valve membrane material, the entire valve membrane was melted, and a heat fluidized layer could not be obtained, and a molded article having a smooth surface could not be obtained.

Measurement of Particle Count

[Example 9]

In a clean booth, a diaphragm valve (diaphragm valve manufactured by Toho Kasei Co., Ltd .: Model No. AV-013,) having a needle valve made of PFA, a 3/4 inch (19.05 mm) tube made of PFA, and a valve membrane obtained in the fifth embodiment. The valve membrane of the liquid contact portion was connected to the valve membrane obtained in Example 5, and the main body having the valve seat was made of homo PTFE) and a 3/4 inch (19.05 mm) tube made of PFA, thereby producing an ultrapure water supply line. In this ultrapure water supply line, ultrapure water was made to flow for a predetermined time with the diaphragm valve open, and it was confirmed that the particle number contained in the outflow water became equal to ultrapure water.

Ultrapure water was then flowed to the ultrapure water supply line at a flow rate of 1 L / min. It is 15 cycles after 30 cycles (after 2 minutes) after starting to let ultrapure water flow as 1 cycle holding the valve open state for 2 second, and then maintaining the valve closed state for 2 second. Ultrapure water) was sampled. The particle number in 1 ml contained in each sampled ultrapure water was measured by the particle counter (the Lion company make). The particle number represented the total number of particle | grains whose particle diameter is 0.1 micrometer or more. The results are shown in Table 2.

[Eighth Comparative Example]

The number of particles was measured in the same manner as in Example 9 except that the diaphragm valve including the valve film obtained in the fifth embodiment was changed to a diaphragm valve including a valve film having the same surface roughness as the valve film obtained in the first comparative example. . The results are shown in Table 2.

10 is a graph showing the relationship between the valve opening and closing water and the number of particles in 1 ml of ultrapure water.

From the results in Table 2, the ninth example using the diaphragm provided with the valve film obtained in the fifth example is the eighth comparative example using the diaphragm provided with a valve film having the same surface roughness as the valve film obtained in the first comparative example. It was found that the number of particle generation is smaller than that.

Measurement of adhesion amount

[Example 10 and Comparative Example 9]

A polyethylene container (capacity 1 L) into which the CMP slurry was put, a slurry pump, and a stop valve were connected in turn using a 1/2 inch (12.7 mm) tube made of PFA. Next to the stop valve, the diaphragm valve (diaphragm valve manufactured by Toho Kasei Co., Ltd .: Model No. AV-013, which is provided with the valve membrane obtained in the sixth embodiment) is provided with the valve membrane and valve seat obtained in the sixth embodiment. The main body is made of Homo PTFE) and a diaphragm valve (diaphragm valve manufactured by Toho Kasei Co., Ltd .: Model No. AV-013, which is provided with a valve film having a surface roughness equivalent to that obtained in the first comparative example. 1) A valve membrane having a surface roughness equivalent to that of the valve membrane obtained in the comparative example, and a main body having a valve seat are made of homo-PTFE) in parallel, and the outlet of each diaphragm valve is connected to the polyethylene container described above to connect a circulation line. Produced.

CMP slurry (Semi-Sperse25, manufactured by Cabot Microelectronics, average aggregate size: 130-180 nm, max. 500 nm or less) A slurry pump (discharge pressure while putting about 1 L into a polyethylene container and opening and closing two diaphragm valves at 2 second intervals (0.1 MPa, flow rate: 1 L / min) was operated to circulate the slurry liquid in the circulation line. After opening and closing two diaphragm valves for 14 hours, 100 hours, and 200 hours, the diaphragm valve was removed and the adhesion amount of the CMP slurry attached to the valve membrane of each diaphragm valve was measured.

The diaphragm valve provided with the valve film obtained in Example 6 was used as the ninth comparative example using the diaphragm valve provided with the valve film which has the surface roughness equivalent to the valve film obtained in Example 10 and a 1st comparative example. Shown in

From the results in Table 3, the tenth example using the diaphragm provided with the valve film obtained in the sixth example is the ninth comparative example using the diaphragm provided with a valve film having the same surface roughness as the valve film obtained in the first comparative example. It was found that the deposition amount of the slurry was smaller than that of the slurry.

The molded article of the present invention can be suitably used as a molded article requiring bend resistance such as a bellows, a diaphragm, an insulating film, a release film, a film for lapping, and the like.

The manufacturing method of the molded object of this invention can be used suitably as a method of manufacturing molded objects, such as a molded object in which bending resistance is calculated | required, an insulation film, a release film, and the film for lapping.

1 is a photograph taken by a polarizing microscope of a valve film 1 obtained in the first embodiment.

2 is a photograph taken by a polarizing microscope of a valve membrane obtained in Example 2. FIG.

3 is a photograph taken by a polarizing microscope of a valve membrane obtained in Example 3. FIG.

4 is a photograph taken by a polarizing microscope of a valve film obtained in Example 4;

5 is a photograph taken by a polarizing microscope of a valve film after cutting obtained in a first comparative example.

6 is a photograph taken by a polarizing microscope of a valve film obtained in Comparative Example 2. FIG.

7 is a photograph taken by a polarization microscope of a valve film obtained in Comparative Example 3. FIG.

Fig. 8 is a surface photograph after immersing the valve membrane 1 obtained in the first embodiment in a slurry liquid. It can be seen that the adhesion of the slurry is small.

Fig. 9 is a surface photograph after immersing the valve film after cutting in the first comparative example in the slurry liquid.

Fig. 10 is a graph showing the relationship between the valve opening and closing water and the number of particles in 1 ml of ultrapure water;

Claims (10)

It is a molded article of polytetrafluoroethylene resin, The polytetrafluoroethylene resin is a modified polytetrafluoroethylene resin, The molded body has a heat fluidized layer on some or all of the surface layers thereof, The surface having the heat-fluid layer has a surface roughness of Ra 0.2 µm or less and Ry 2.0 µm or less. The surface having a heat fluidized layer according to claim 1, wherein the surface having a thermal fluidized layer is treated with a surface pressure of 0.2 MPa or more by a mold surface of a mold, The molded surface has a surface roughness of Ra 0.2 µm or less and Ry 1.5 µm or less and a surface temperature at the time of treatment of 330 ° C or more. The molded body according to claim 1 or 2, wherein the thermal fluidized layer has one more heat history times than layers other than the thermal fluidized layer inside the molded body. delete The molded article according to claim 1 or 2, wherein the polytetrafluoroethylene resin is made of polytetrafluoroethylene obtained by suspension polymerization or emulsion polymerization. The molded article of Claim 1 or 2 which contains 0.5-30 mass% of polytetrafluoroethylene resins further with the thermoplastic resin which has hot melt workability. The molded body of Claim 1 or 2 which is a diaphragm valve film | membrane and the surface which has a heat fluidized layer is a liquid contact side. A diaphragm valve having a valve seat formed in a valve body and a diaphragm provided with a diaphragm valve film that is press-contacted or spaced from the valve seat. The diaphragm valve membrane is a molded article according to claim 1 or 2, characterized in that the diaphragm valve. A diaphragm pump for discharging a fluid by reciprocating movement of a diaphragm valve membrane, wherein the diaphragm valve membrane is a molded body according to claim 1 or 2. Calcining the preform obtained by preforming polytetrafluoroethylene powder and obtaining a calcined body, A step of heating the mold surface of the mold having a surface roughness of Ra 0.2 μm or less and Ry 1.5 μm or less to 330 ° C. or more, Processing a part or all of the surface of the fired body with a surface pressure of 0.2 MPa or more by the mold surface; Preparation of the molded object characterized by manufacturing the molded object of the polytetrafluoroethylene resin which has a heat fluidized layer in the surface layer of one part or all of the surface, and whose surface roughness of the surface which has the said heat fluidized layer is Ra 0.2 micrometer or less and Ry 2.0 micrometer or less. Way.

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