JP3375115B2 - Method for producing fluororesin molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] TECHNICAL FIELD The present invention has an antistatic property.
A novel method for producing a fluororesin molded article. In detail
Is a fluororesin molded article having substantially no ion exchange group
Good while maintaining the unique characteristics of the fluororesin on the surface layer of
An antistatic layer that has an effective antistatic effect
Efficient formation can be achieved with a minimum number of methods
A method for producing a fluororesin molded article having antistatic properties
is there. [0002] 2. Description of the Related Art Fluororesins are chemically resistant, heat resistant, and electrically resistant.
Excellent insulation properties and contamination resistance, suitable for a wide range of industrial fields
Has been used. However, the surface resistance of fluororesin is
The major disadvantage is that it is very high and is easily charged with static electricity
Having. [0003] For example, a foot used in a semiconductor manufacturing process.
Silicon resin wafer carrier has fluororesin
Due to the chargeability, it is easy to adsorb fine particles in the atmosphere,
As a result, fine particles adsorbed on the wafer carrier are
Contaminates the wafer being carried and
There is a problem that the defective rate of a product to be manufactured is increased. In addition, a pipe for transferring a flammable liquid is
The friction caused by the passage of flammable liquid through the pipe.
Rubbing generates static electricity, which can cause ignition. Conventionally, a fluororesin molded article is provided with an antistatic property.
Conductive powder to fluororesin for the purpose of giving
Known resin compositions and molded articles comprising the compositions are known.
Have been. For example, Japanese Patent Application Laid-Open No. 61-37842,
JP-A-62-223255, JP-A-2-25575
No. 1 discloses a fluorine resin such as tetrafluoroethylene.
With carbon powder and carbon fiber powder, fibrous conductive titanium oxide
Resin composition mixed with conductive powder such as zinc oxide
A method for obtaining a molded body is disclosed. Japanese Patent Application Laid-Open No. 8-59864 discloses that
By subjecting the surface layer of the fluororesin molded body to plasma treatment
By converting the CF bond into a C = C bond,
The method for producing a fluororesin molded body having a conductive surface
It has been disclosed. Further, it imparts hydrophilicity to the fluororesin molding.
Japanese Patent Application Laid-Open No. 1-98641 for the purpose of
Is hydrophilic containing ion exchange groups upon irradiation
Monomers are graphed on the surface of a fluororesin porous tube
A method for polymerization is disclosed. [0008] SUMMARY OF THE INVENTION
Among them, obtained by resin composition mixed with conductive powder
The molded body is made of a large amount of conductive powder to impart antistatic ability.
It is necessary to mix the powder, so that the resulting
Conductive powder or impurities contained in it
There is a problem that substances are eluted. Such a problem is
It causes the phenomenon of contaminating the substance that comes in contact with the compact,
Then, using the fluororesin molded body as a wafer carrier
In the case, the particles caused by the eluted conductive powder
Wafer held by the wafer carrier
Causes the phenomenon of contamination. In addition, the fluid transfer
In the use of IP, it causes the phenomenon of contamination of the fluid.
There is a risk. Further, the whole molded body contains the conductive powder.
By being composed of fluororesin, the characteristics of fluororesin
The electrical properties and contamination resistance are impaired,
Limited use in required applications. On the other hand, for the purpose of imparting hydrophilicity, hydrophilic
In the case of the method of introducing the
Nitrogen resin is originally a decomposition type resin in such a reaction.
And quantitatively and quantitatively introduce monomers
Difficult, very thin, about a few hundred angstroms below the surface
Only the ion-exchange groups are provided at the thickness. Also,
Decomposition by irradiating the surface of the plastic molding
There is also concern that the resin may cause particle generation
It is. As a result, it is obtained by the above manufacturing method.
Fluororesin moldings do not sufficiently reduce surface resistance and charge
There is still room for improvement in the prevention effect, contamination, etc. [0012] SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention has been developed.
They conducted intensive research. As a result, the ion exchange group
A fluororesin having a group that can be converted into at least a surface layer
In some fluororesin moldings, ion-exchange groups
Group that can be converted to organic quaternary ammonium hydroxide solution
Hydrolyzes and converts to an ion exchange group to form an antistatic layer.
By forming, the electrical insulation inherent in fluororesin
Demonstrate good antistatic effect while maintaining edge characteristics
Along with efficiently obtaining a fluororesin molded body,
During the hydrolysis, the surface of the antistatic layer can be maintained at a high purity.
This led to the completion of the present invention. That is, the present invention substantially comprises an ion exchange group.
Ion exchange on at least the surface layer of
A fluororesin having a group that can be converted to a substituted group,
A group that can be converted to an ion exchange group present in the surface layer is
Hydrolysis with quaternary ammonium oxide aqueous solution
Has antistatic properties, characterized by conversion to an ion exchange group.
This is a method for producing a fluororesin molded article. [0014] DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, a molded article is formed.
As a fluororesin having substantially no ion exchange groups
Has properties inherent to fluoroplastics, especially electrical insulation properties
Is used. Specifically, an ion exchange group or
A known fluororesin which does not substantially contain a conductive substance, for example
For example, polytetrafluoroethylene, tetrafluoroethylene
Copolymer of ethylene and alkyl vinyl ether, tetra
Co-polymerization of fluoroethylene and hexafluoropropylene
Coalescence, polymonochlorotrifluoroethylene, tetraf
Fluoroethylene and perfluorodimethyldioxol
Copolymer of polyperfluoroalkenyl vinyl ether
And the like. [0015] The above alkyl vinyl ether is
Oroalkyl vinyl ether or partially has a hydrogen atom
Is a polyfluoroalkyl vinyl ether. Concrete
Generally, the general formula, R_f(CH_Two)_lOCF = CF_Two (However, R_fIs a perfluoroalkyl group, l is 0 or
It is one. ) The alkyl vinyl ether occupies in the obtained copolymer.
Is less than 0.2% by weight, preferably
It is preferable to use it in the range of 0.15% by weight or less. [0016] In addition, a primer having substantially no ion exchange group is used.
A group that can be converted to an ion exchange group
Having a fluororesin alone or mixed with the above fluororesin
It is also possible to use. Further, in the present invention, the above ion exchange
Fluororesin moldings having substantially no groups can be ion-exchanged.
It is not limited to an embodiment in which the group is completely absent,
Ion exchange groups inevitably present in fluoroplastics are
It is forgiving. Such an allowance is required depending on the application.
Dimensional stability, adsorption and permeability are different.
Although it is not possible to limit the ion exchange group,
Less than 0.2 mol%, especially 0.1%
Molar percent or less is preferred. Incidentally, in the present specification, the fluorine resin
The amount of ion-exchange groups included depends on the total monomers of the ion-exchange groups.
Of the monomer unit. In addition, in fluorine resin
The amount of groups that can be converted to ion exchange groups contained in
Of the group that can be converted to an exchange group
The composition is expressed as follows: The ion exchange group used in the present invention
Known fluororesins having a group that can be converted are particularly known.
Used without restrictions. For example, tetrafluoroethylene
And a monomer having a group that can be converted to an ion exchange group.
Polymers are preferably used. In this case, the moldability and physical properties of the copolymer are improved.
30 mol% or less based on tetrafluoroethylene for the purpose of
Hexafluoropropylene below, general formula below CF_Two= CFO (CH_Two)_aC_bF_{2b + 1} (Where a is 0 or 1 and b is an integer of 1 to 10)
You. Alkyl vinyl ethers represented by
Fluorine-containing monomers such as nochlorotrifluoroethylene
It can be mixed and used. It also has a group that can be converted to an ion exchange group.
Perfluorosulfonic acid ion exchange
As a monomer having a group that can be converted to a group, CF_Two= CFO [CF_TwoCF (CF_Three) O]_oCF_TwoCFR_F
SO_TwoX (Where X is F or Cl, R_FIs F or CF_ThreeIn
And o is an integer of 1 to 3. ) Monomer
Can also be converted to a perfluorocarboxylic acid ion exchange group
The monomer having a group represented by the following general formula CF_Two= CFO [CF_TwoCF (CF_Three) O]_p(CF_Two)_qY (However, Y is CO_TwoR (where R is a lower alkyl group)
You. ), CN, COF, COCl, and p is 1 to 3.
Is an integer, and q is an integer of 2 to 8. ) Or CF_Two= CFO (CF_Two)_rOCF (CF_Three) Y (However, Y is CO_TwoR (where R is a lower alkyl group)
You. ), CN, COF, COCl, and r is an integer of 2 to 8.
Is a number. ) Are suitably used. It has a group which can be converted into these ion exchange groups.
Specific examples of such monomers include: CF_Two= CFOCF_TwoCF_TwoSO_TwoF, CF_Two= CFOCF_TwoCF (CF_Three) OCF_TwoCF_TwoSO
_TwoF, CF_Two= CFOCF_TwoCF (CF_Three) OCF_TwoCF (C
F_Three) OCF_TwoCF_TwoSO_TwoF, CF_Two= CFOCF_TwoCF (CF_Three) SO_TwoF, CF_Two= CFOCF_TwoCF (CF_Three) OCF_TwoCF (C
F_Three) SO_TwoF, CF_Two= CFO (CF_Two)_3-8CO_TwoCH_Three, CF_Two= CFOCF_TwoCF_TwoOCF_TwoCF (CF_Three) CO_TwoC
H_Three Is mentioned. Further, these monomers may be used alone.
It is good, and there is no problem if it is mixed and used. Ion exchange with the above tetrafluoroethylene
Copolymerization with a monomer having a group that can be converted to a substituent is known.
Can be used without any limitation. That is, the solution
Polymerization method among suspension polymerization method and emulsion polymerization method
The optimum polymerization method may be selected in consideration of the above conditions. In any case, a group that can be converted to an ion exchange group
Tetrafluoroethylene in a dispersion or solution of a monomer having
Copolymerization is carried out by dissolving Tylene under pressure,
Monomers or tetramers with groups that can be converted to ion exchange groups
When using other monomers in addition to fluoroethylene,
The monomer is a gas such as hexafluoropropylene.
If mixed with tetrafluoroethylene,
If it is a liquid such as vinyl ether, it is converted to an ion exchange group
What is necessary is just to mix and polymerize with the monomer which has the group which can be formed. Emulsion polymerization or suspension without using organic solvent
In the case of polymerization, water is suitable as a dispersion medium. On the other hand,
In the case of liquid polymerization or suspension polymerization using an organic solvent, organic
Solvent acts as a chain transfer agent, reducing the molecular weight of the polymer
Physical properties of the resulting copolymer may be inferior.
Therefore, the solvent used is preferably a fluorine-based liquid. As such a fluorine-based liquid, specifically,
Is perfluorobutane, perfluoropentane, par
Fluorohexane, perfluoroheptane, perfluoro
Perfluoroalkanes such as looctane, perfluoro
Perf such as cyclobutane and perfluorocyclohexane
Fluorocycloalkanes, perfluoroethers,
Perfluorotertiary amines such as -fluorotributylamine
, Perfluoromorpholines, trifluoromonoc
Chlorofluoroethanes such as loroethane are preferably used.
Can be As a polymerization initiator, in the case of emulsion polymerization, persulfuric acid is used.
Persulfates such as ammonium are preferably used, and
In the case of polymerization or suspension polymerization, a known organic radical generator is used.
Used, but consider the heat resistance of the resulting copolymer
And fluorine-based diacyl peroxides are preferably used.
Specifically, the following can be mentioned. (CF_ThreeCF_TwoCO_Two)_Two, (HCF_TwoCF_TwoC
O_Two)_Two, (ClCF_TwoCF_TwoCO_Two)_Two, (CF_ThreeCF_TwoCF
_TwoCO_Two)_Two, (CF_ThreeCF_TwoCF_TwoOCF (CF_Three) CO_Two)
_TwoThe pressure of the fluoroolefin during polymerization is
Although it cannot be unconditionally determined by the composition and the polymerization temperature,
0kg / cm^Two-G is preferred. Also use the polymerization temperature
Since it depends on the decomposition temperature of the polymerization initiator,
Although it cannot be determined, it is usually 0 to 100 ° C, and is used as a polymerization initiator.
When a fluorine-based diacyl peroxide is used,
50 ° C. is preferred. In the present invention, it can be converted into an ion exchange group.
At least part of the surface layer has a fluororesin having a group
(Hereinafter abbreviated as a precursor molded body)
Is not particularly limited. Examples of typical manufacturing methods
The following method is mentioned if it shows. That is, a group that can be converted to an ion exchange group is
Ion exchange with a fluororesin alone or with the fluororesin
A mixture with a fluororesin having substantially no groups (hereinafter referred to as
These are collectively referred to as precursor resins. ) Molding and molding
A group that can be converted into ion-exchange groups throughout the molded body by the method
For producing a molded article having a presence (Example of production of a precursor molded article)
1). In the above method, conversion to an ion exchange group
Fluoro-resin having a group that can be
Any known mixing method can be used for mixing with the fluororesin
Adopted without limitation, but for example, Henschel mixer
And kneader brabenders. Further, as another method for producing the precursor molded body,
A small number of fluororesin moldings having substantially no ion exchange groups
At least part of the surface layer is fused with the precursor resin,
Manufacture molded products with groups that can be converted to on-exchange groups
Method (Preparation molded article production example 2). If the above method is specifically described, the front of the mold
After the precursor resin is present in a layer, the ion-exchange groups are
Injection molding or blow molding of fluorocarbon resin
Forming a surface layer by forming a precursor molded body
(Production example 2-1 of precursor molded body)
Fluorine trees that have virtually no groups that can be converted to on-exchange groups
A resin molded body is formed, and then the surface of the formed body or
Precursor resin is present on the inner surface of the mold
After that, insert into the mold, close the mold, and heat and fuse.
(Preparation of Precursor Molded Article)
Example 2-2), a layer made of a precursor resin and an ion exchange group
Layer made of fluororesin having substantially no convertible group
Multi-layer extrusion with a resin containing at least one
Manufactures precursor moldings by multi-layer blow molding
(Preparation molded article production example 2-3) and the like.
You. In the method for producing a precursor molded article described above, a mold
In the case of using the method, the presence of the precursor resin on the inner surface of the mold
A known method suitable for the purpose is appropriately adopted.
For example, powder electrostatic spraying, suspension
It is preferable to use a method of coating with
The method of causing the presence of the arsenal is also suitable. Furthermore, a fluororesin molded body
The method of causing the precursor resin to exist on the surface of the resin is also particularly limited.
However, a method by application with a suspension is preferred. Specific examples of the fluororesin molding according to the present invention
The shape is not particularly limited. For example, as shown in FIG.
Structure, such as a wafer carrier with
Of thin objects such as tubes, pipes, etc., sheets, films, etc.
Body and the like. The molding method of these molded articles
Injection molding, extrusion molding,
Known methods such as transfer molding, compression molding, and blow molding
May be selected as appropriate. The fluororesin composition having antistatic ability of the present invention
The feature is present on at least a part of the surface layer in the precursor molded body.
A group that can be converted to an ion-exchange group
Then, it is manufactured by forming an antistatic layer. The feature of the present invention is that the ion exchange group is
In a hydrolysis reaction that converts a replaceable group into an ion exchange group,
To use organic quaternary ammonium hydroxide aqueous solution
You. Here, NaOH, KOH
Alkali metal hydroxide and Ca (OH)_TwoEtc. Arca
When using earth metal hydroxide, conversion to ion exchange groups
Exchange is achieved, but alkali metal salts or
Alkaline earth metal salts are by-produced and remain in the antistatic layer.
You. Therefore, these metal salts will be
It may elute slowly, which is not preferable. On the other hand, in the hydrolysis reaction, an organic hydroxyl is used.
Prepared by a method using an aqueous solution of quaternary ammonium fluoride.
Fluororesin moldings with antistatic properties
Group ions and alkaline earth metal ions are contained in the molded body
No metal ions when in use
In the semiconductor manufacturing process, which dislikes contamination by metal ions
It is preferably used. Cation exchange after hydrolysis in the present invention
The counter ion of the group is ammonium ion,
Conversion to hydrogen ions and other ammonium ions is known.
The method is adopted without any problems. In the hydrolysis reaction, several to several tens of weight% of organic water is used.
The molded body is immersed in a quaternary ammonium oxide aqueous solution for several minutes to
It may be heated at room temperature to 150 ° C for more than a hundred and ten hours, but more
Preferably, 5 to 40% by weight of an organic hydroxylated quaternary ammonium salt
For 1-12 hours at 50-150 ° C.
A water splitting reaction may be performed. Here is the organic ammonium hydroxide
There is no particular limitation as long as it is nickel, but more preferably tet
Laalkyl ammonium hydroxide is used
You. To accelerate this hydrolysis reaction, methyl alcohol
(Hereinafter abbreviated as MeOH), ethyl alcohol
(Hereinafter abbreviated as EtOH), dimethyl sulfoxide
(Hereinafter abbreviated as DMSO).
That is valid. It should be noted that an aqueous quaternary ammonium hydroxide solution is used.
Metal ions and alkaline earth metal ions contained in
It is preferable that the concentration of
pb or less. Ion exchange group provided by the above method
Is a group that can be converted to an ion exchange group present in the precursor molded body
Is determined by the type. For example, perfluorosulfur
A phonic acid group or a perfluorocarboxylic acid group;
And these ion exchange groups are perfluorocarbon chains or
-Chemically bonded to fluororesin via fluoroether chain
I agree. These ion exchange groups will be described in more detail.
For example, the perfluorosulfonic acid group has the following general formula -CFR_FSO_ThreeM (However, R_FIs F or CF_ThreeAnd M is a hydrogen atom, or
NR '_FourWherein R 'is a hydrogen atom or lower
It is a kill group. ). ) And also perfluoro
The carboxylic acid group has the following general formula -CFR_FCO_TwoM (However, R_FAnd M are the same as above. )
Things. Of these ion exchange groups, perfluoro
Sulfonic acid groups are resistant to perfluorocarboxylic acid groups.
When heat is good and the counter ion to bind is hydrogen ion,
-Higher antistatic ability than fluorocarboxylic acid groups
It is suitable. In the present invention, the surface layer of the fluororesin molded article
Antistatic layer formed in the presence of ion exchange groups
This generally results in a surface resistivity of 10¹³Less than Ω, good
Preferably 10^TenIndicates a surface resistance of Ω or less. Incidentally, the present invention
, The surface resistivity is described in JIS K-6911
Was carried out according to the method described above. In the present invention, the ions of the above antistatic layer
The concentration of the exchange group is 0.25 mol% or more, preferably 0.25 mol%.
5 to 20 mol%, more preferably 0.25 to 18 mol%
Is preferred to impart good antistatic properties
No. That is, used in the production example of the precursor molded body described above
Concentration of groups that can be converted to ion exchange groups in the precursor resin
With 0.25 mol% or more, preferably 0.25 to 20
%, More preferably 0.25 to 18 mol%
Is preferred. The thickness of the surface layer having an ion exchange group is
1 to 500 μm and 80% or less of the thickness of the molded body
Setting of the molding conditions so that
Preferably, a conversion is performed. Specifically, the antistatic
The upper limit of the thickness of the stop layer is 80% or less of the thickness of the molded body.
Below, preferably 40% or less, more preferably 30% or less
It is. Particularly, the upper limit of the layer is 500 μm or less in absolute thickness.
More preferably, it is below. In the present invention, the thickness of the antistatic layer is
As described above, it is important for achieving the effects of the present invention.
You. The thickness of the antistatic layer depends on the hydrolysis conditions and the precursor resin layer.
It is adjusted by the method and conditions of formation of. That is, in the production example 1 of the precursor molded body described above,
Hydrolysis conditions control the thickness of the antistatic layer
You. That is, under the conditions of the hydrolysis reaction,
Of quaternary ammonium fluoride aqueous solution, temperature, species of organic solvent
Type, amount, abundance of groups that can be converted to ion exchange groups,
It cannot be determined unconditionally depending on the composition and the like. Therefore,
Hydrolysis conditions and thickness of antistatic layer formed by hydrolysis
If the density in the vertical direction is measured, it will be charged within the range of the present invention.
The thickness of the prevention layer can be adjusted. In Production Examples 2-1 to 3-3 of the precursor molded body,
It is adjusted according to the molding method and conditions. That is, molding
Sometimes controls the thickness of the precursor resin layer and hydrolyzes the layer
By controlling the thickness of the antistatic layer
You. More specifically, mold inside or fluororesin molding
In the method of making the precursor resin powder exist on the body,
In the case of the powder electrostatic spraying method,
Depending on the flow gas flow rate, pattern gas flow rate, nozzle shape, etc.
Control and as one of the suspension application methods
However, in the suspension spray method, the solvent, resin concentration, spray gas
Control the thickness of the precursor resin layer by controlling the flow rate
can do. Also be present by film
Method by adjusting the thickness of the sandwiched film
The thickness of the precursor resin layer can be controlled. In addition,
Of a method as shown in Manufacturing Method 2-2 of
In this case, the gap is determined by the outer dimensions of the compact and the inner dimensions of the mold.
Even so, the thickness can be controlled. Also, multi-layer extrusion
In the method based on the shape, the nozzle shape, extrusion rate ratio, pull
Control the thickness of the precursor resin layer by controlling the removal speed, etc.
Can be Depending on various conditions, the surface is ion-exchanged.
High concentration of groups, low concentration of ion exchange groups in the thickness direction
Concentration gradient is formed, but the ion exchange group concentration is
The thickness of the layer having a concentration of 0.25 mol% or more is 1 μm or more
It is preferable that an ion exchange group is provided below the antistatic layer.
With a concentration of less than 0.2 mol%, especially 0.1 mol% or less
The body should be there. Of course, the antistatic layer and the substrate
Between the transitions where the ion exchange group concentration is in between
It does not matter if there is a shift. Hydrolysis is carried out on the entire surface of the fluororesin molding.
It is preferable to do this, but depending on the application, one side, or
Partial hydrolysis may be performed. Also, depending on the application
It is not necessary to hydrolyze the entire precursor resin layer. this
In case, control the thickness of antistatic layer by hydrolysis condition
can do. Further, a fluororesin molded body was filled with
Used for thin objects such as
When used, the insulation and ion impermeability of fluororesin
To sufficiently exhibit properties such as transient properties and chemical resistance,
The thickness of the portion having substantially no ion exchange group is 10 μm.
controlling the upper limit of the thickness of the layer so as to secure at least m
Is preferred. In the present invention, the antistatic layer comprises
It is generally present on the surface, but depending on the application,
You may make it exist in a part of molded object surface. For example, thin pieces such as films, sheets, etc.
Antistatic on the inner or outer surface of surfaces, tubes and pipes
Structure with no antistatic layer on the other side
May be. For example, one side of a fluororesin molding
That static electricity is not an issue on the other side.
It can be used satisfactorily for other uses. Thickness of antistatic layer of the present invention, ion exchange group
Abundance and substrate thickness are, for example, infrared absorption spectra
(Hereinafter simply referred to as IR spectrum)
So you can know. That is, the fluororesin composition of the present invention
A film with a thickness of several tens to several hundreds of micrometers vertically from the surface of the feature
And the IR spectrum is separated from the surface by several μm
By measuring the transmission or reflection spectrum at
Or several to several tens μm from the surface of the fluororesin molding of the present invention.
To measure the reflection spectrum of the cut surface
Thereby, the thicknesses of the antistatic layer and the base are calculated. Such an antistatic layer is substantially free of ion-exchange groups.
Present on the surface of a substrate made of fluororesin not having
By lowering the surface resistivity, conventional conductive materials can be added.
To provide antistatic properties by applying
Particle generation is extremely low
There is a problem with contamination such as rear
It is useful in applications where In addition, the substrate
Since fluorine resin does not contain a large amount of additives, fluororesin
The strength of the molded body is also sufficient,
Ideal for physically demanding applications. Also, all
Compared to ion exchange resins that have ion exchange groups in the body
Since pure ions do not penetrate into the interior, impurity ions
Small amount of adsorption, contacting the obtained fluororesin molding
Extremely low contamination of impurity ions to the article. The fluororesin molding of the present invention will be described later.
The adsorption amount of the drug solution measured by the method described above is 50 ppb / cm^TwoLess than,
Especially 10ppb / cm^TwoIt is as follows. From this, it can be obtained by the method of the present invention.
The obtained fluororesin molding is the same as the wafer carrier.
Best for applications where contamination is an issue
Is done. In the present invention, the obtained fluororesin molding
The antistatic effect of the body should be confirmed by the voltage decay rate
In general, a voltage of 10 kV is applied for 1 minute, and then
The voltage decay rate after one second is 70% or more, preferably 90%
The above is preferred. The file manufactured by the method of the present invention described above.
Except for the surface layer, the nitrogen resin molded body
Because there is a portion that does not contain
They can be treated equally, and
The following which is seen in the fluororesin molded body where the on-exchange group exists
Problem can be almost avoided. That is, like an ion exchange membrane,
Molded products using resins having exchange groups
Dimensional change due to swelling of the molded body
And adsorbs and permeates ions, inorganic substances, or organic substances
Phenomenon occurs. Therefore, the wafer carrier
If used in applications, contamination of wafers that come into contact with it
Problems may arise. For example, an ion exchange group
Fluorine-based ion exchange membranes and
On-exchange resins are known, but these resins
It is intended for permeation and adsorption of
About 10 mol% of the group. Therefore, the above wafer
Stain resistance, a characteristic of fluoroplastics like Harrier
Fluorine-based ion exchange
Adsorption of organic substances and ions, etc., possessed by membranes and ion exchange resins
Characteristics are not favorable. In addition, filters that require antistatic capability
For use in films and tubes made of fluorine resin
Inorganic substances such as ions and water, and organic substances such as alcohol
There is a problem that a substance is transmitted and adsorbed. [0065] As will be understood from the above description, the present invention
According to the method of the invention, the ion is added to the surface layer of the fluororesin molded body.
A layer having an exchange group can be provided;
Maintains the original electrical insulation of the molded body and provides an antistatic layer.
A fan that exhibits a good antistatic effect while maintaining high purity
A nitrogen resin molded article can be obtained. That is, the fluorine resin having the antistatic ability
The molded body is treated with an aqueous quaternary ammonium hydroxide solution.
By hydrolyzing, when the fluororesin molded article is used
No metal ions are eluted, so contamination by metal ions
It is suitably used in a semiconductor manufacturing process that dislikes the above. The usual fluororesin is 10¹⁶Ω or more
It has surface resistance and the voltage decay rate after one hour is several percent
On the other hand, according to the method of the present invention,
The sheet resistance is 10¹³Ω, and the voltage decay rate is less than several seconds.
Within 100% and practically no charge
It is possible to obtain a fluororesin molding. Therefore, the antistatic prepared by the present invention
Fluororesin moldings with a stop layer are compatible with current fluororesins.
Unlikely, static electricity is hardly generated and static electricity is generated.
Dispersion when born is fast. Also manufactured by the present invention
Fluororesin molded articles have substantially ion-exchange groups on the substrate.
When immersed in a chemical solution, ions and
Because there is no adsorption or permeation of organic or organic substances, contamination from chemicals
There is no dyeing, and this fluororesin molded body is
Contaminated these chemicals and water more than necessary when moving to
And no dimensional change of the molded body.
It retains the excellent physical properties inherent in the base resin.
Wear. From the above, it can be obtained by the method of the present invention.
Fluororesin moldings are used in the semiconductor manufacturing industry,
Industry, the chemical industry, or general physics and chemistry fields
Suitable in fields where generation and dissolution of metal ions are disliked
Can be used. Specifically, there is no adhesion of dust and the like due to static electricity.
As a peripheral component during semiconductor manufacturing,
Valves, fittings, valves, check valves, strainers, drugs
Liquid container, vacuum tweezers, vacuum tweezers tips,
Packing, O-ring, gasket, seat, lining
Material, coating material, tweezers, tongs, dipper
ー, holder, strainer, flasher, fan
Flannel, measuring cylinder, basket, stir bar, beaker
ー, wipe cleaner, tank, bolt, nut, bottom
Suitable for tools, snowboards, trays, plate heaters, etc.
Can be As a jig for a wafer carrier or the like,
Wafer carrier, handle for wafer carrier,
Boxes, retainers and processes for wafer carriers
Tray, protector for wafer, wafer board, L
CD basket, LCD carrier, wafer tray,
Cover for wafer tray, spring for wafer tray
Wafer, wafer pack, wafer shipper, mask carrier
Box, mask carrier box, mask carrier
Handle, mask pack, mask case, device key
Carrier, handle for device carrier, side rail
Chip tray, chip tray cover, chip tray
Case, chip transfer tray, chip cleaning cap
Suitable for rear, chip washer, chip tray box, etc.
It can be used appropriately. Especially the fluororesin molding of the present invention
Wafer carrier made of body has excellent antistatic properties
Therefore, due to static electricity, fine particles in the operating atmosphere
Not only can the adhesion of
Generation, contamination by impurity ions, and metal ions
No problems such as contamination due to wafers
It has the effect of keeping the pass rate low.
You. The tubes (including pipes) of the present invention
Transfer of flammable liquids using the
This prevents the generation and accumulation of static electricity, and thus the danger of ignition.
In addition to preventing ruggedness,
Generation, swelling due to the transfer liquid, and the permeability of the transfer liquid
It is extremely useful without undue problems. Further, in the field of food production, the present invention
By using the shape, adhesion of dust which is a hygiene problem
Used in food production because it can prevent
Surface coatings on equipment such as mixer vessels and
Suitable for stirring blades, tubes, trays, belts, etc.
it can. [0074] The present invention will now be described in detail with reference to Examples.
However, the present invention is limited to these examples.
There is no. The surface resistivity and voltage of the fluororesin molding were
Decay rate, amount of drug solution adsorbed, and Na⁺, K⁺The ion elution amount is as follows
I asked as follows. (1) Surface resistivity Measured according to JIS K-6911, and by the following formula
The surface resistivity was calculated. [0077] (Equation 1) [0078] Where ρ_S: Surface resistivity (Ω) d: Outer diameter of inner circle of surface electrode (cm) D: inside diameter of the ring electrode on the surface (cm) R_S: Surface resistance (Ω) Voltage 500V Measurement time 30 seconds Average 3 times (2) Voltage decay rate Static Honest Meter S-5109 (Shishido
Using a voltage of 10 kV for 1 minute,
The voltage after turning off was measured. Resin size: 40 × 40 × 0.25 mm Decay rate = (initial voltage−voltage after t time) / initial voltage (unit
Rank:%) (3) Na⁺, K⁺Ion elution amount After rinsing the test piece with ultrapure water for 20 minutes,
It was put into 500 ml of water and heated at 80 ° C. Every fixed time
Coupled ultrapure water sampling and inductively coupled plasma mass spectrometry
Analysis (ICP-MS) and the Na contained in the ultrapure water was analyzed.
⁺, K⁺The amount of ions is measured by the test piece surface area^TwoCalculated per hit
did. (4) Amount of chemical solution adsorbed After rinsing the test piece with ultrapure water for 20 minutes, wash the test piece
500l sulfuric acid for electronics industry
And hold at room temperature for 10 minutes to adsorb sulfuric acid on the test piece.
I let it. Next, the test piece was taken out, and the test piece was treated with ultrapure water for 20 minutes.
After rinsing for minutes, put in 500 ml of ultrapure water and
Heated. After 2 hours, sample ultrapure water and
Analyze by on-chromatography and determine the amount of sulfuric acid contained in the ultrapure water.
Specimen surface area 1cm^TwoPer unit, and the amount of drug solution adsorbed
did. Reference Example 1 In a stainless steel 500 ml reactor equipped with a stirrer
1,1,2-Trichlorotrifluoroethane purified by distillation
After charging 320 g of gas, the inside is evacuated and then nitrogen
To atmospheric pressure. 0.039 g of MeOH
And 33.5 g of CF_Two= CFOCF_TwoCF (CF_Three) OCF_TwoCF_TwoSO_TwoPut F
After that, the rotation speed of the stirring motor was set to 800,
Introduce fluoroethylene and increase pressure to 4kg / cm^Two-G
did. Next, while maintaining the inside of the reactor at 25 ° C.,
1,1,2-tris (septafluorobutyryl) peroxide
1.77 Lichlorotrifluoroethane solution (5% by weight)
g was introduced to initiate polymerization. During the polymerization, the polymerization temperature is 25
C. 120 minutes after the start of the reaction, the pressure in the reactor was released.
And connect the reactor to a vacuum pump via a cooling trap
And reduce the pressure while stirring to reduce the boiling point of the solvent, unreacted monomers, etc.
Point components were collected in the trap. After distillation, dismantle reactor
Then, the copolymer is taken out and vacuum dried at 150 ° C. for 12 hours.
As a result, 24 g of a copolymer was obtained. Nuclear magnetic resonance spectrum, infrared absorption spectrum
According to the measurement results of
95.7 mol% of monomer units based on ethylene, CF_Two= CF
OCF_TwoCF (CF_Three) OCF_TwoCF_TwoSO_Two4.3 monomer units based on F
% Of the copolymer. Also,
The specific melt viscosity of the copolymer at 372 ° C. was 4.6 × 10
⁶Poise. Embodiment 1 The copolymer obtained in Reference Example 1 was coated with a 0.25 mm thick filter.
Melt-molded, and then tetramethylammonium hydroxide
(Hereinafter abbreviated as TMAH) / MeOH / H_TwoO
= 15/25 / 60wt% aqueous solution at 100 ° C
Hydrolysis was performed for 3 hours to form an antistatic layer. This file
When the abundance of ion-exchange groups in the film was examined,
Approximately 4.3 mol%, approximately 0.2 μm from the surface.
28 mol%, 30 μm from the surface, and near the center
Was 0.08 mol% and 0.02 mol%. Therefore,
The concentration of ion exchange groups in the antistatic layer is 0.25 mol
% Or more has a thickness of 20 μm. Next, the surface resistivity of this film was measured.
3.4 × 10⁸Ω, and measure the voltage decay rate.
Then, it attenuated 100% in one second. Also this film
1.0 μg / cm^TwoIn
Was. When this film was immersed in ion exchange water overnight
No elongation due to roller swelling was observed. Na⁺
Ion elution amount 1 hour, 3 hours, 5:00
0.8 μg / cm^TwoHereinafter, 0.8 μg /
cm^TwoBelow, 0.8 μg / cm^TwoLess than, K⁺ion
The elution amount was 1 hour, 3 hours, and 5 hours after the start of elution.
The elution amount is 0.4 μg / cm^TwoHereinafter, 0.4 μg / cm^TwoLess than
Lower, 0.4 μg / cm^TwoIt was below. Further, 0.2% obtained by the above method was obtained.
Particle generation test for 5mm film
Was carried out. That is, first, the film is 5 cm × 10 c
Cut out into m samples, class 1000 cleanle
Rinse with ultrapure water for 10 minutes in the room. Then, in the container
Add isopropyl alcohol for electronics industry and shake for 5 minutes
And then left. One day later, isopropyl alcohol for electronics industry
Were replaced and shaken for 5 minutes and then left. Similar replacement
The procedure was repeated 1 day, 7 days, and 14 days later.
0.3-2μm particles contained in pill alcohol
The number of particles by a particle counter (KL-2, manufactured by Rion)
Measured using 2). 750 pieces / m after one day
1, 90 cells / ml after 7 days, 45 cells / ml after 14 days
Particles were observed. Note that the isoelectric for electronic industry used in this experiment was used.
Particles contained in propyl alcohol are 20-4
It was 0 / ml. Examples 2-3 Except that the hydrolysis temperature was changed using the film of Example 1.
Performs hydrolysis in the same manner as in Example 1 to form an antistatic layer.
Formed. Table 1 shows the hydrolysis temperature and the antistatic layer
Thickness of the layer having an ion exchange group concentration of 0.25 mol% or more
Surface resistivity, voltage decay rate after 1 second, and Na⁺, K⁺
The result of measuring the ion elution amount (5 hours after the start of elution)
showed that. [0091] [Table 1] Examples 4 to 8 Using the film of Example 1, the concentration of the TMAH aqueous solution was changed.
Hydrolysis is carried out in the same manner as in Example 1 except that
An prevention layer was formed. Table 2 shows the concentration of the hydrolyzate and the amount of the antistatic layer.
Layer having a concentration of ion exchange groups in the layer of 0.25 mol% or more
Thickness, surface resistivity, voltage decay rate after 1 second, and Na⁺,
K⁺The ion elution amount (5 hours after the start of elution) was measured.
The results are shown. [0094] [Table 2] Examples 9 to 10 Except for using the film of Example 1 and changing the hydrolysis time
Performs hydrolysis in the same manner as in Example 1 to form an antistatic layer.
Formed. Table 3 shows the hydrolysis time and the antistatic layer.
Thickness of the layer having an ion exchange group concentration of 0.25 mol% or more
Surface resistivity, voltage decay rate after 1 second, and Na⁺, K⁺
The result of measuring the ion elution amount (5 hours after the start of elution)
showed that. [0097] [Table 3] Comparative Examples 1 and 2 Using the film of Example 1, TMAH was used as the hydroxide.
Performed except that NaOH or KOH was used instead
Hydrolysis was performed in the same manner as in Example 1 to form an antistatic layer.
Was. Table 4 shows the types of the hydroxides and the antistatic layers.
Layer having a concentration of ion exchange groups in the layer of 0.25 mol% or more
Thickness, surface resistivity, voltage decay rate after 1 second, and Na⁺,
K⁺Ion elution amount (1 hour after the start of elution, 3 hours
And after 5 hours). [0100] [Table 4] Examples 11 to 12 Organic solvent used for hydrolysis using the film of Example 1
Hydrolysis was carried out in the same manner as in Example 1 except that
An antistatic layer was formed. Table 5 shows the hydrolyzate composition and the antistatic layer
Layer having a concentration of ion exchange groups in the layer of 0.25 mol% or more
Thickness, surface resistivity, voltage decay rate after 1 second, and Na⁺,
K⁺The ion elution amount (5 hours after the start of elution) was measured.
The results are shown. [0103] [Table 5]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a typical structure of a wafer carrier constituted by a fluororesin molded article of the present invention. DESCRIPTION OF REFERENCE NUMERALS 1 Wafer carrier main body 2 Wafer holding groove

Claims (1)

(57) [Claim 1] A fluororesin having a group that can be converted to an ion exchange group is present on at least the surface layer of a fluororesin molded article having substantially no ion exchange group, A method for producing a fluororesin molded article having antistatic properties, comprising hydrolyzing an existing group that can be converted into an ion exchange group with an aqueous quaternary ammonium hydroxide solution to convert it into an ion exchange group.