JPH1180960A - Production of releasing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of efficiently producing a releasing sheet having excellent releasing performance without leaving unreacted compds. in the releasing sheet by stably generating discharge plasma under about atmosheric pressure. SOLUTION: A solid dielectric 6 is set to at least either counter face under the pressure in the vicinity of the atmospheric one in a gas atmosphere contg. a gaseous fluorine compd., a sheet material 7 is inserted into the space between the counter electrodes, and, furthermore, discharge plasma generated by applying the pulsification electric field thereto is brought into contact with at least one side of the sheet material to form fluorine thin film on the sheet material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a release sheet by bringing discharge plasma into contact with a sheet material at a pressure near atmospheric pressure.

[0002]

2. Description of the Related Art A release sheet is formed by coating and fixing a release agent on a film or sheet of plastic or paper, and is used for protecting the surface of an adhesive of a tape or a label or manufacturing a paste resin product. It is widely used as a process carrier. Conventionally, addition-polymerization-type and condensation-polymerization-type silicone release agents have been frequently used as release agents.

An addition polymerization type silicone release agent is a silicone compound having an addition polymerizable vinyl group, which is coated on the surface of a film or sheet, and is polymerized and fixed by heat, ultraviolet rays, electron beams or the like. Then, a release sheet (hereinafter, the description includes the film in the sheet) is manufactured. Therefore, in the release sheet obtained by the above method, a small amount of unreacted monomer remains on the mechanism, which migrates to the adhesive and reduces the adhesive strength, or the adverse effect of adsorbing dust in the air. Awake.

[0004] The condensation polymerization type silicone release agent is a release agent utilizing a condensation reaction of a silicone compound. When reacted at a low temperature, unreacted monomers remain, and this causes the same problem as described above. In order to cure the silicone compound, a high temperature exceeding the melting point of the synthetic resin is required. If this is not possible, the curing reaction requires a long time, and the heating and drying furnace becomes very long. Therefore, if a synthetic resin thin film is formed on heat-resistant paper and is not subjected to a release treatment, high-temperature treatment is difficult, and even today, a release sheet made of a paper base material is mainly used.

For this reason, various methods have been proposed. For example, Japanese Patent Application Laid-Open No. 55-165925 proposes a method of performing low-pressure plasma treatment on a sheet substrate in an atmosphere of a fluorocarbon compound. However, the above method
Since the process had to be performed in a low-pressure atmosphere, the equipment became batch-type, which was not suitable for continuous production.

As a countermeasure, Japanese Patent Application Laid-Open No. 2-48626 proposes a method for generating discharge plasma near the atmospheric pressure by performing discharge plasma in an atmosphere composed of argon, acetone and / or helium. ing. However, helium is expensive and has economic problems.

Japanese Patent Application Laid-Open No. 9-3219 discloses that a solid dielectric is provided on at least one counter electrode surface under a pressure near the atmospheric pressure of a mixed gas containing a fluorine atom-containing gas and an inert gas. There has been proposed a method of releasing a sheet material with a discharge plasma generated by applying an electric field between the electrodes. However, although there is an advantage that the mold release treatment can be performed near the atmospheric pressure, the stability of the plasma discharge is not sufficient.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is intended to stably generate a discharge plasma under a pressure of about the atmospheric pressure to thereby release a release sheet. An object of the present invention is to provide a method for efficiently producing a release sheet having excellent release ability without leaving unreacted compounds.

[0009]

According to a method of manufacturing a release sheet of the present invention, a solid dielectric is formed on at least one of the opposing surfaces of an opposing electrode under a pressure near the atmospheric pressure of a gas atmosphere containing a gaseous fluorine compound. The sheet material is inserted between the opposed electrodes, and a discharge plasma generated by applying a pulsed electric field is brought into contact with at least one surface of the sheet material to form a fluorine-based thin film on the sheet material. It is characterized by being formed.

It is known that under a pressure near the atmospheric pressure, except for a specific gas such as helium, ketone, etc., the plasma discharge state is not stably maintained and the state is instantaneously shifted to the arc discharge state. However, studies by the inventors have already revealed that a stable discharge plasma can be obtained by applying a pulsed electric field near atmospheric pressure. It is presumed that a stable discharge plasma can be obtained because the pulsed electric field realizes a cycle in which the discharge is stopped before starting the arc discharge and the discharge is started again.

The above-mentioned pressure near the atmospheric pressure is defined as 100 to 8
The range of 700 to 780 Torr is preferable from the viewpoint that the pressure is 00 Torr, the pressure is easily adjusted, and the apparatus is simplified.

The method for producing a release sheet according to the present invention is performed in an apparatus having a pair of opposed electrodes, and a solid dielectric placed on at least one of the opposed surfaces of the electrodes. The portion where plasma is generated is between the solid dielectric and the electrode when a solid dielectric is installed on one of the electrodes, and between the solid dielectrics when the solid dielectric is installed on both of the electrodes. Space.

Examples of the electrode include those made of simple metals such as copper and aluminum, alloys such as stainless steel and brass, and intermetallic compounds. The counter electrode preferably has a structure in which the distance between the counter electrodes is substantially constant in order to avoid occurrence of arc discharge due to electric field concentration. Examples of an electrode structure that satisfies this condition include a parallel plate type, a cylindrical opposed plate type, a spherical opposed plate type, a hyperboloid opposed plate type, and a coaxial cylindrical structure.

The solid dielectric is provided on one or both of the opposing surfaces of the electrodes. At this time, the electrode on the side on which the solid dielectric is placed is in close contact with the electrode, and the opposing surface of the contacting electrode is completely covered. This is because if there is a portion where the electrodes directly face each other without being covered by the solid dielectric, an arc discharge occurs therefrom.

Examples of the solid dielectric include plastics such as polytetrafluoroethylene and polyethylene terephthalate, glass, silicon dioxide, and aluminum oxide (Al ₂ O).
₃ ), zirconium oxide (ZrO ₂ ), titanium oxide (T
metal oxides such as iO ₂ ), and multiple oxides such as barium titanate.

The solid dielectric may be in the form of a sheet or a film, but preferably has a thickness of 0.05 to 4 mm. If the thickness is too large, a high voltage is required to generate discharge plasma. If the thickness is too small, dielectric breakdown occurs when a voltage is applied, and arc discharge occurs.

In particular, when the solid dielectric has a relative dielectric constant of 10 or more in a 25 ° C. environment, high-density discharge plasma can be generated at a low voltage, and a release sheet can be formed in a short time. Or it can be manufactured at high speed. However, if the dielectric constant is less than 10, efficient and high-speed production as described above becomes difficult. A material having a large relative dielectric constant is known to be about 18,500, but the upper limit of the relative dielectric constant is not particularly limited. Among them, the relative dielectric constant is 10 to 100 (25
C. environment) is particularly preferred.

As such a solid dielectric, for example,
The aforementioned zirconium oxide, metal oxides such as titanium oxide,
Double oxides such as barium titanate are exemplified. A titanate compound is known as a ferroelectric substance. In the case of titanium oxide alone, the relative permittivity differs depending on the crystal structure, and the relative permittivity of a rutile type crystal structure is about 80. In the case of a compound of titanium oxide and at least one selected from metal oxides such as Ba, Sr, Pb, Ca, Mg, and Zr, the relative dielectric constant is about 2,000 to 18,50.
0, and the relative dielectric constant can be changed depending on purity and crystallinity.

On the other hand, in the case of the above-mentioned titanium oxide alone, the composition changes drastically depending on the heating state. For example, when heated in a reduced state, oxygen deficiency is caused, so that the environment to be used is limited. Is 10 ⁴ Ω · c
Care must be taken because the film becomes about m in length, and when a voltage is applied, it tends to shift to arc discharge. For this reason, it is better to use the solid dielectric containing aluminum oxide than titanium oxide alone, and it is preferable that the solid dielectric be a metal oxide coating composed of 5 to 50% by weight of titanium oxide and 50 to 95% by weight of aluminum oxide. Since it is thermally stable, it can be used more preferably.

The above-mentioned metal oxide film comprising titanium oxide and aluminum oxide is thermally stable, has a relative dielectric constant of about 10 to 14, a specific resistance of about 10 ¹⁰ Ω · cm, and prevents arc discharge. Less likely to occur. If the proportion of aluminum oxide is less than 50% by weight, arc discharge is likely to occur, and if it exceeds 95% by weight, the relative dielectric constant becomes about 7, and a high applied voltage is required to generate discharge plasma.

It is particularly preferable that the solid dielectric is a metal oxide film containing zirconium oxide and having a film thickness of 10 to 1,000 μm. When zirconium oxide alone is used, it has a relative dielectric constant of about 12, which is advantageous for generating discharge plasma at a low voltage. Usually, zirconium oxide is converted to yttrium oxide (Y
₂ O ₃ ), calcium carbonate (CaCO ₃ ), magnesium oxide (MgO), etc. are added within 30% by weight to suppress expansion and shrinkage due to crystal transformation and stabilize.
Such additives may be added. The relative dielectric constant is determined by the type of the additive and the crystallinity of the metal oxide, and it is preferable that at least 70% by weight be zirconium oxide. For example, if yttrium oxide is 4 to 2
The zirconium oxide coating to which 0% by weight is added is preferable because the relative dielectric constant is about 8 to 16.

The distance between the electrodes is determined by the thickness of the solid dielectric,
It is determined in consideration of the magnitude of the applied voltage, the purpose of utilizing the plasma, and the like. The shortest distance between the solid dielectric and the electrode when the solid dielectric is installed on one of the electrodes, or the shortest distance between the solid dielectrics when the solid dielectric is installed on both of the electrodes, in any case , 1 to 50 mm. When the shortest distance is less than 1 mm, the interval between the discharge plasma generating portions is insufficient for manufacturing a release sheet, and when it is more than 50 mm, it is difficult to generate uniform discharge plasma.

FIG. 1 shows an example of a pulse voltage waveform. Waveforms (A) and (B) are impulse waveforms, waveform (C) is a square wave waveform, and waveform (D) is a modulation waveform. Although FIG. 1 shows a case where the voltage application is repeated positive and negative, a pulse of a type that applies a voltage to either the positive or negative polarity side may be used.

The pulse voltage waveform in the present invention is not limited to the above-mentioned waveforms, but the shorter the rise time and the fall time of the pulse, the more efficient the ionization of the gas during the plasma generation, and the higher the surface treatment. Is advantageous.

In particular, it is preferable that the rise time and / or the fall time of the pulse be 40 ns to 100 μs. If it is less than 40 ns, it is not realistic, and if it exceeds 100 μs, the discharge state easily shifts to an arc and becomes unstable. More preferably, it is 50 ns to 5 μs. still,
Here, the rise time refers to the time during which the voltage change is continuously positive, and the fall time refers to the time during which the voltage change is continuously negative.

Further, modulation may be performed using pulses having different pulse waveforms, rise times, fall times, and frequencies. Such modulation is suitable for high-speed continuous surface treatment.

The frequency of the pulse electric field is 1 kHz to 100
Preferably, it is kHz. If it is less than 1 kHz, it takes too much time for the treatment, and if it exceeds 100 kHz, it is easy to shift to arc discharge.

The pulse duration in the pulse electric field is preferably 1 to 1000 μs. 1 μs
When the discharge time is less than 1,000 μs, the discharge becomes unstable.
When it exceeds, it is easy to shift to arc discharge. More preferably, it is 3 μs to 200 μs. Here, one pulse duration is an example shown in FIG.
It refers to the time during which a pulse is continuous in a pulse electric field composed of repetition of FF. In the case of the intermittent pulse as shown in FIG. 2A, the pulse duration is equal to the pulse width time, but in the case of the pulse having the waveform as shown in FIG. Means time including

Further, in the present invention, the intensity of the pulse electric field is preferably set to 1 to 100 kV / cm. 1k
If it is less than V / cm, the forming speed of the release sheet becomes slow, and if it exceeds 100 kV / cm, an arc discharge occurs, which is not preferable.

FIG. 3 is a block diagram showing an example of the configuration of a power supply circuit for forming a pulse electric field satisfying the above conditions, and FIG. 4 is an equivalent circuit diagram showing the principle of operation. Indicated by In FIG. 4, SW1 to SW4 are semiconductor elements that function as switches in the switching inverter circuit in FIG.
By using a semiconductor device having a turn-on time and a turn-off time of 0 ns or less, the electric field strength is 1 to 100
It is possible to realize a high-voltage and high-speed pulse electric field with kV / cm and pulse rise and fall times of both 40 ns to 100 μs.

Next, the principle of operation will be briefly described with reference to FIG. + E is a positive DC voltage supply unit, and -E is a negative DC voltage supply unit. SW1 to SW4 are switching elements made of the high-speed semiconductor elements described above. D
Numerals 1 to 4 denote diodes, and I1 to I4 indicate the directions in which electric charges move.

First, when SW1 is turned on, the electric charge is I1
Then, one side (positive load) of a pair of electrodes placed at both ends of the discharge space is charged. Next, S
By turning off W1 and then turning on SW2 instantaneously, the charge charged to the positive load becomes SW2 and D
4 and move in the direction of I3.

Next, after SW2 is turned off, SW3
Is turned on instantaneously, the charge moves in the direction of I2 and charges the other electrode (negative load). Furthermore, SW3
Is turned off and then the switch SW4 is turned on instantaneously, so that the electric charge charged to the negative load moves in the direction of I4 through the switches SW4 and D2.

By repeating the above operation, an output pulse having the waveform shown in FIG. 5 can be obtained. Table 1 shows this operation table. The numerical values shown in Table 1 correspond to the numerical values given to the waveforms in FIG.

[0035]

[Table 1]

The advantage of the above-described circuit is that even if the load impedance is high, the charged electric charge is transferred to SW
2 and D4 or SW4 and D2 to discharge reliably, and high-speed turn-on switching elements SW1 and SW3 to perform high-speed charging. A pulsed electric field having an extremely short rise time and fall time as shown in FIG. 2 can be applied to a load, that is, between a pair of electrodes. The pulse electric field used in the method for producing a release sheet of the present invention does not prevent superposition of a DC electric field.

The method for producing the release sheet of the present invention utilizes the plasma generated between the opposed electrodes by the above-described method of generating a discharge plasma unique to the present invention.
When a solid dielectric is provided between the opposed electrodes, or on a surface facing one electrode, between the solid dielectric and the other electrode,
Alternatively, when a solid dielectric is provided on the opposing surfaces of both electrodes, a sheet material for producing a release sheet is disposed between the solid dielectrics.

Examples of the sheet material include stretched or unstretched films and sheets composed of organic materials, inorganic materials, and composite materials thereof. Examples of the material include low-, medium-, high-density polyethylene, Linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, polyvinyl chloride resin, polymethyl methacrylate, polybutyl methacrylate, styrene-methyl methacrylate Examples include copolymers, polyethylene terephthalate, polycarbonate, urethane resins, silicone resins, synthetic resins such as polyphenylene sulphite, papers, various glasses, ceramics and the like, and a laminate of these may be used.

The method for producing a release sheet of the present invention is performed by applying a pulsed electric field between the above-mentioned counter electrodes in a gas atmosphere containing a gaseous fluorine compound. The gas atmosphere containing a gaseous fluorine compound is
It refers to both a gaseous fluorine compound alone atmosphere and a mixed atmosphere of a gaseous fluorine compound and any other gas.

As the gaseous fluorine compound, carbon tetrafluoride (CF ₄ ), carbon hexafluoride (C ₂ F ₆ ), ethylene tetrafluoride (C ₂ F ₄ ), propylene hexafluoride (C
₃ F _6), fluorocarbon compounds such as 8 fluoride cyclobutane; 2 tetrafluoromethane (CH ₂ F _2), 4 fluoride ethane _{(C 2 H 2 F 4)} , 4 hexafluoropropylene (C ₃ H
₂ F _4), 3 hexafluoropropylene (C ₃ H ₃ F ₃₎ fluorinated hydrocarbon compounds such as, 1 chloride trifluoride methane (CClF
₃ ) halides of fluorinated hydrocarbon compounds such as monochloromethane difluoride (CHClF ₂ ), dichlorotetrafluorocyclobutane (C ₄ H ₂ Cl ₂ F ₄ ), sulfur hexafluoride (SF)
₆ ) and fluorine-substituted organic compounds such as alcohols, acids and ketones, and at least one of them can be used. Of these, harmful hydrogen fluoride does not generate carbon tetrafluoride, carbon hexafluoride,
Propylene hexafluoride, cyclobutane octafluoride and the like are preferably used.

In the production method of the present invention, a sufficient film-forming rate can be obtained in an atmosphere in which the concentration of the gaseous fluorine compound is about 5% by volume. preferable. Examples of the diluent gas include rare gases such as neon, argon, and xenon, and nitrogen gas.
At least one of these is used. Among them, argon and nitrogen are preferably used as the diluting gas from the viewpoint of stability, efficiency and cost of the discharge plasma.

The ratio of the gaseous fluorine compound in the diluent gas atmosphere is preferably 1 to 10% by volume, and when the concentration of the gaseous fluorine compound is less than 1% by volume, the release sheet is not formed. If the reaction does not progress or progresses, the speed is too slow and if it exceeds 10% by volume, a substance that has not progressed sufficiently may adhere to the surface and the surface of the release sheet may become tacky. .

Therefore, in the method for producing a release sheet of the present invention, the most preferable atmosphere is a fluorocarbon gas and / or
Alternatively, it is a mixed gas composed of 1 to 10% by volume of a fluorohydrocarbon gas and 99 to 90% by volume of argon and / or nitrogen.
Also, the higher the concentration, the higher the speed of forming the release sheet. However, in the method of the present invention, a sufficient forming speed can be obtained at a concentration of 5% by volume. Is more preferred.

When the gaseous fluorine compound is a gas at normal temperature and normal pressure, it is used as it is as a component of the gas atmosphere, and the method of the present invention can be most easily performed.
However, when the gaseous fluorine compound is liquid or solid at normal temperature and normal pressure, it may be used after being vaporized by a method such as heating.

FIG. 6 shows an example of an apparatus for performing the method for producing a release sheet according to the present invention. In this apparatus, the lower electrode 5
A solid dielectric 6 is provided on the top, and discharge plasma is generated in a space between the solid dielectric 6 and the upper electrode 4. The processing vessel 2 includes a gas introduction pipe 8, a gas exhaust port 10, and a gas exhaust port 11. The gaseous fluorine compound is supplied from the gas introduction pipe 8 to the discharge plasma generation space 3. In the present invention, since the portion in contact with the generated discharge plasma is processed, in the example of FIG. 6, the upper surface of the sheet material 7 is processed. If you want to treat both sides of the sheet material,
What is necessary is just to place the sheet material 7 so as to float in the discharge plasma generation space 3.

It is preferable that the gaseous fluorine compound is uniformly supplied to the plasma generation space. When processing in a mixed gas of a gaseous fluorine compound and an inert gas, since the inert gas is lighter than the processing gas, a device has been devised to avoid non-uniformity during supply. In particular, when a sheet material having a large area is processed, care should be taken since unevenness tends to occur.

In the example shown in the apparatus of FIG.
Is connected to the electrode 4 having a porous structure, and the gaseous fluorine compound is supplied to the plasma generation space 3 from above the sheet material through the holes of the electrode 4. The inert gas is separately supplied through an inert gas introduction pipe 9. The structure is not limited to such a structure as long as the gas can be supplied uniformly, and a means such as stirring or blowing the gas at a high speed may be used.

In producing a release sheet, when introducing a gaseous fluorine compound or an inert gas into the processing container 2, air remaining in the processing container 2 may be exhausted from the exhaust port 11 in advance. Preferably, the excessively introduced gaseous fluorine compound or inert gas is supplied to the gas outlet 1 of the processing vessel 2.
Emitted from 0.

The processing container 2 has an upper surface 2 a and a lower surface 2 b made of stainless steel, a side surface 2 c made of polymethyl methacrylate, and an insulator 2 d disposed between the upper surface 2 a and the upper electrode 4. The material of the processing container 2 includes, for example, resin and glass, but is not particularly limited. Metals such as stainless steel and aluminum can also be used as long as they have a structure insulated from the electrodes.

The processing container 2 is a sheet material processing container 2 so that the sheet material can be continuously subjected to discharge plasma processing.
Two slits 1 to serve as entrance and exit
2, 12 are open on both sides. This slit 12
Can be opened and closed so that the processing container 2 can be opened and closed as needed.

The discharge plasma treatment of the present invention may be carried out by heating or cooling the sheet material, but is sufficiently possible at room temperature.

[0052]

According to the manufacturing method of the present invention, by applying a pulsed electric field to the electrodes, a stable discharge plasma can be generated even near the atmospheric pressure, whereby the gaseous fluorine compound existing between the electrodes can be generated. Are activated to fluorinate the surface of the sheet material. Therefore, since the processing is performed near the atmospheric pressure, the plasma density is high, and the release processing speed is higher than that in the conventional vacuum processing. In addition, since various radicals generated from the gaseous fluorine compound are directly chemically bonded to the surface of the sheet material, a low-molecular-weight residue as in the related art may migrate to the pressure-sensitive adhesive and reduce the adhesive strength. No change in releasability over a long period of time.

[0053]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the method for producing a release sheet of the present invention will be described in more detail with reference to Examples, but the present invention is not limited to only these Examples.
In the following embodiment, a power supply manufactured by Heiden (a semiconductor device manufactured by IXYS, model number T) according to the equivalent circuit diagram shown in FIG.
O-247AD).

Example 1 The discharge plasma processing apparatus shown in FIG. 6 was used. The processing container 2 is a cube having a side of 500 mm, the distance between the upper and lower electrodes is 3 mm, and the width of each of 4 and 5 is 350 mm.
mm × length 150mm × thickness 150mm metal electrode,
The surface of the electrode 5 is coated with a thermal spray film 6 of zirconium oxide (solid dielectric 6; dielectric constant 16, thickness: 500 μm). The sheet material 7 has a basis weight of 95 g / 300 mm in width.
glassine paper of m ² (manufactured by Oji Paper Co., Ltd., 3G-95-111
-124) was passed from the right slit 12 while contacting the solid dielectric 6 between the upper electrode 4 and the lower electrode 5, passed through the left slit 12, and wound up the sheet material 7. .

Next, propylene hexafluoride (C ₃ F ₆ ) is supplied from the gas introduction pipe 8, and argon gas is supplied from the inert gas introduction pipe 9 so that the concentration of propylene hexafluoride becomes 3 (volume)%. As described above, and gas was replaced to a pressure near the atmospheric pressure of 760 Torr. Thereafter, the mixed gas is supplied to a 30 SLM (Standard Liteperp).
er Minute), a peak value of 14 kV is applied between the upper electrode 4 and the lower electrode 5 while being introduced into the processing vessel 2 at a total flow rate of
A pulse electric field having a frequency of 8 kHz and a rise time of 500 ns was applied, the running speed of the sheet material 7 was set to 30 m / min, and one surface of the base material was subjected to discharge plasma treatment to produce a release sheet. With respect to the obtained release sheet, the peeling force and the peeling force with time with heat were measured by the evaluation method described later, and the results are shown in Table 2.

Example 2 One side of the sheet material was subjected to discharge plasma treatment in the same manner as in Example 1 except that a 25 μm-thick polyethylene terephthalate film (Lumilar # 25, manufactured by Toray Industries, Inc.) was used as the sheet material. Then, a release sheet was prepared, and a peeling force and a thermal aging peeling force were measured by an evaluation method described later, and the results are shown in Table 2.

COMPARATIVE EXAMPLE 1 The distance between the upper and lower electrodes was 5 mm, and the surface of the lower electrode facing the upper electrode was 1 mm thick as a solid dielectric.
Except that the polytetrafluoroethylene was coated,
The same discharge plasma processing apparatus as in Example 1 was used. Carbon tetrafluoride was used as the gaseous fluorine compound, helium was used as the inert gas, and the volume mixing ratio was maintained at 760 Torr, with carbon tetrafluoride / helium = 1/99.

As the sheet material 7, glassine paper having a width of 300 mm and a basis weight of 95 g / m ² (3G-95 manufactured by Oji Paper Co., Ltd.)
−111-124), and the discharge plasma processing conditions were such that the peak value 12.4 between the upper electrode 4 and the lower electrode 5 was used.
A continuous electric field of a sin wave having a frequency of 15 kHz and a frequency of 15 kHz is applied to set the traveling speed of the sheet material 7 to 10 m / min. A stable discharge plasma is generated on one side of the sheet material by helium gas, and the surface treatment is performed. A mold sheet was prepared. With respect to the obtained release sheet, the peeling force and the peeling force with time with heat were measured by the evaluation method described later, and the results are shown in Table 2.

Comparative Example 2 One side of the sheet material was subjected to discharge plasma treatment in the same manner as in Comparative Example 1, except that a 25 μm thick polyethylene terephthalate film (Lumilar # 25, manufactured by Toray Industries, Inc.) was used as the sheet material. To produce a release sheet, by the evaluation method described below, the peeling force, the thermal peeling force over time was measured,
The results are shown in Table 2.

Comparative Example 3 Glassine paper having a basis weight of 95 g / m ² (manufactured by Oji Paper Co., Ltd., 3G-
95-111-124) was coated with 1 g / m ^{2 of} solvent-free silicone (KNS-3100, manufactured by Shin-Etsu Chemical Co., Ltd.) and cured to obtain a release sheet. With respect to the obtained release sheet, the peeling force and the peeling force with time with heat were measured by the evaluation method described later, and the results are shown in Table 2.

Comparative Example 4 As a sheet material, a solvent-free silicone (KNS-31 manufactured by Shin-Etsu Chemical Co., Ltd.) was coated on one side of a 25 μm thick polyethylene terephthalate film (Lumilar # 25 manufactured by Toray Industries, Inc.).
00) was coated at 0.7 g / m ² and cured to obtain a release sheet. With respect to the obtained release sheet, the peeling force and the peeling force with time with heat were measured by the evaluation method described later, and the results are shown in Table 2.

[0062]

[Table 2]

Evaluation method (1) Peeling force The release sheet was supported by a stainless steel plate (1 mm thick), and Nitto polyester tape # 31B was applied to the treated surface of the release sheet.
(Manufactured by Nitto Denko Corporation) was adhered, and the 180-degree peeling adhesion was measured according to the adhesion test of JIS Z0237 (Testing method for adhesive tape / adhesive sheet).

(2) Thermal Release Peeling Force The release sheet was supported by a stainless steel plate (1 mm thick), and Nitto polyester tape # 31B was applied to the treated surface of the release sheet.
(Nitto Denko Co., Ltd.) was affixed and left for 1 month in an atmosphere of 50 ° C., and then peeled 180 degrees and measured for adhesive strength according to the adhesive strength test of JIS Z 0237 (adhesive tape / adhesive sheet test method). did.

[0065]

The method for producing a release sheet according to the present invention is configured as described above.
It can be produced at high speed and continuously, and can be produced more economically than conventional coating methods.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an example of a waveform of a pulse voltage applied between opposed electrodes.

FIG. 2 is an explanatory diagram of the duration of one pulsed electric field.

FIG. 3 is a block diagram of a power supply that generates a pulsed electric field.

FIG. 4 is an equivalent circuit diagram of a power supply that generates a pulsed electric field.

FIG. 5 is a diagram of an output pulse signal corresponding to an operation table of a pulsed electric field.

FIG. 6 is an example of a discharge plasma processing apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 AC power supply (high voltage pulse power supply) 2 Processing container 3 Discharge plasma generation space 4 Upper electrode 5 Lower electrode 6 Solid dielectric 7 Sheet material 8 Gas introduction pipe 9 Inert gas introduction pipe 10 Gas outlet 11 Exhaust port 12 Slit ( Doorway of base sheet)

Claims (1)

[Claims] At least one opposing surface of a counter electrode is provided with a solid dielectric under a pressure near the atmospheric pressure of a gas atmosphere containing a gaseous fluorine compound, and a sheet material is inserted between the opposing electrodes and pulsed. A method for producing a release sheet, comprising: contacting at least one surface of a sheet material with a discharge plasma generated by applying a converted electric field to form a fluorine-based thin film on the sheet material.