JP2002283517A - Fluororesin laminated sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluororesin laminated sheet which facilitates installation work at a job site due to both excellent flexibility and strength, capable of being snugly attached to a lining surface and preventing early lifting due to air residue (air biting) or the like and having a high durability. SOLUTION: The fluororesin laminated sheet comprises a heat resistant bare cloth formed of a woven fabric or a knitted fabric of greige goods treated fibers of heat resistant fibers substantially containing no carbon element and a residual amount of the greige goods of 0.05 to 0.50 wt.% in terms of a carbon element amount as relatively much greige goods, and the fluororesin sheet laminated on the cloth via an adhesive layer made of a heat fusible resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention is useful for various applications such as lining materials, interior materials, kitchen facilities, construction and civil engineering materials utilizing the chemical resistance, corrosion resistance, release properties, slipperiness, etc. of fluororesins. And a fluororesin laminated sheet. The fluororesin laminate sheet of the present invention is excellent in workability and also excellent in durability.

[0002]

2. Description of the Related Art Various chemical solutions are widely used as raw materials and cleaning agents in various chemical plants, including semiconductor manufacturing. Some of these chemicals are highly reactive or corrosive, and containers and pipes used for storing and transporting such chemicals are lined on the inner surface with a laminated sheet of fluorine resin having high chemical resistance.

[0003] Such a fluororesin laminated sheet usually has a structure in which a fluororesin sheet is laminated directly or via an adhesive layer on a heat-resistant base cloth, and various structures and materials have been conventionally proposed ( JP-B-39-25288,
JP-B-48-33274, JP-B-56-36064
No., JP-A-50-2073, JP-B-57-5180
No., JP-B-52-144473, JP-A-59-311
No. 48, JP-B-63-4792, JP-B-5-3826
No., JP-A-6-170978, JP-B-8-18410
No., JP-A-2000-85055, JP-A-2000-850
56 publications or WO 00/10805 pamphlet).

[0004] As a method of manufacturing a fluororesin laminated sheet,
A batch method such as a method in which a sheet or a base cloth is simply laminated and heat pressed or a method in which the sheet and the base cloth are wrapped around a steel pipe, fixed with a metal wire, and then put into a heating furnace (Japanese Patent Publication No. 59-25)
No. 288, JP-A-50-2073, JP-B-57-51
No. 80, JP-B-63-4792, JP-B-5-3826
Publications) and a fluororesin continuous sheet, and if necessary, a continuous resin film for bonding and a continuous heat-resistant base fabric are unwound from the respective rolls and heated by a heating roll heated to a melting point of the fluororesin or higher. A continuous method in which the surface of a sheet is adhered to a base fabric while being melted (Japanese Patent Laid-Open No. 2000-85)
055, JP-A-8-18410, JP-A-200
0-85056 or WO00-10805) is known.

In this continuous method, since the heat conductivity of the fluororesin is poor, in order to efficiently transfer the heat from the heating roll to the fluororesin sheet, heating is performed from at least the base fabric side (the base fabric is brought into contact with the heating roll). Is required.

The lining method using a fluororesin laminate sheet is performed in the following steps, for example, taking the lining of a chemical tank as an example. (1) The inner surface of the metal tank to be lined is blasted to remove an oxide film on the surface. (2) Immediately apply a primer, then apply an adhesive and dry. (3) An adhesive is applied to the heat-resistant base fabric side of the plurality of fluororesin laminated sheets cut according to the shape of the inner surface of the tank, and then dried. (4) The fluororesin laminated sheet is temporarily fixed to the inner surface of the tank by pressing the surface coated with the adhesive, and then the mirror portion and the flange portion of the fluororesin laminated sheet are bent and the groove is cut. (5) The joints of the plurality of fluororesin laminated sheets whose shapes have been adjusted are welded to form an integral unit. (6) By heating the fluororesin laminated sheet from its surface while sucking and extracting air existing between the inner surface of the tank and the fluororesin laminated sheet by a pump from a vacuum hole provided in the fluororesin laminated sheet, Thus, the adhesion between the fluororesin laminated sheet and the inner surface of the tank is ensured.

Therefore, the fluororesin laminated sheet includes:
In addition to the properties of fluororesin such as chemical resistance, workability such as flexibility that can be deformed along the tank inner surface, and durability such as long-term adhesion to the tank inner surface are required.

For example, when a laminated sheet having poor flexibility is used, the air bleeding in the above-mentioned construction step (6) becomes insufficient, and air remains on the joint surface between the laminated sheet and the lining surface. In addition to increasing the penetration of the chemical solution to the bonding surface, the laminated sheet may even be lifted up early.

As a method for imparting flexibility to the laminated sheet, a low-density base cloth may be used as the heat-resistant base cloth. However, in this case, the strength of the laminated sheet is reduced, and the fluororesin sheet and the heat-resistant base cloth are used. When the resin is melt-bonded, the fluororesin or the hot-melt resin adhesive used protrudes to the back surface of the base fabric, and as a result, the strength with the inner surface of the tank becomes insufficient.

In the conventional continuous method, heating is performed only from the base fabric side (Japanese Patent Laid-Open No. 2000-85055, WO
00-10805 pamphlet), the base fabric is overheated more than necessary, the strength and flexibility of the base fabric may be reduced, and the base fabric may be damaged during the bending process in the above-mentioned construction step (4). Sometimes.

[0011] A method of heating from both the fluororesin sheet side and the base fabric side during the production of the laminated sheet (Japanese Patent Laid-Open No. 8-1841)
No. 0) or a method of heating from only the fabric side or both the fluororesin sheet side and the fabric side for the purpose of removing wrinkles (Japanese Patent Laid-Open No. 2000-85056). Tetrafluoroethylene (P
The sheet of TFE) has a large coefficient of thermal expansion and a large coefficient of thermal shrinkage, and there is a problem that wrinkles and wavy due to shrinkage still occur in the width direction of the base fabric, particularly at the end, and thus a wide laminated sheet can be continuously formed. It could not be manufactured. Problems relating to the thermal expansion and shrinkage of the fluororesin also exist in the case of the method of heating from the base cloth side.

In order to suppress the generation of wrinkles, it is only necessary to apply a tension in the width direction to the fluororesin sheet at the time of heating and then stretch it. However, since it is necessary to melt the fluororesin, sufficient tension can be applied to the fluororesin sheet. There is no present.

[0013] The heat-resistant base fabric of the fluororesin laminated sheet is usually made of a heat-resistant but rigid, easily breakable fiber such as glass fiber. Therefore, it is provided to weaving in the form of strands in which dozens to hundreds of fibers are bundled. In these steps, a sizing agent (binder or binder) is used to prevent the fibers from being damaged or to increase the density of the woven fabric. (Sizing agent). The sizing agent mainly comprises a hydrocarbon compound such as starch and oil. The content of the sizing agent is usually 1.5 to 2.0% by weight of the woven fabric.

When such a heat-resistant woven fabric containing a sizing agent is used as a base fabric for a fluororesin laminated sheet, removing the sizing agent lowers the mechanical strength and flexibility of the base fabric. If present in a large amount, it may be thermally decomposed and foamed at the time of melt lamination to cause poor appearance, etc. In addition, the affinity (adhesion) between the resin such as fluororesin and the fiber may be reduced, and further melting may occur. Since the fluororesin does not easily enter between the fibers during lamination and the filling of the woven fabric may be insufficient, a base fabric from which the sizing agent is thermally decomposed and removed by heat treatment (heat cleaning treatment) after weaving is used. ing. When the sizing agent in the base cloth is subjected to the conventional continuous method of heating from the base cloth side, it is thermally decomposed and further reduced, and as described above, the strength and flexibility of the base cloth are further reduced, and the workability is reduced. It is the present situation.

The problem on the side of the base fabric can be considerably improved by increasing the thickness of the fluororesin sheet, but the workability as a laminated sheet is reduced by that much, and when the thickness is thin, it becomes more noticeable.

[0016]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluororesin laminated sheet which retains the strength and flexibility required for a heat-resistant base fabric and is excellent in both workability and durability. .

[0017]

That is, the present invention relates to a woven or knitted fabric of a sizing agent-treated fiber of a heat-resistant fiber substantially containing no carbon element, wherein the remaining amount of the sizing agent is expressed in terms of the amount of carbon element. The present invention relates to a fluororesin laminated sheet in which a woven or knitted fabric having a relatively large sizing agent residual amount of 0.05 to 0.50% by weight is used as a heat-resistant base cloth, and a fluororesin sheet is directly laminated on the base cloth.

The present invention also relates to a woven or knitted fabric of a heat-resistant fiber sizing agent-treated fiber substantially containing no carbon element, wherein the remaining amount of the sizing agent is 0.05 to 0.1% in terms of the carbon element amount. 50
A woven or knitted fabric having a relatively large amount of the sizing agent remaining as a heat-resistant base fabric, and a fluororesin laminated sheet formed by laminating a fluororesin sheet on the base fabric via an adhesive layer made of a heat-fusible resin. About.

Furthermore, the present invention provides a heat-resistant base fabric made of a woven or knitted fabric of glass fiber treated with a sizing agent, on which a fluororesin sheet is directly or via an adhesive layer made of a hot-melt resin. Color difference ΔE (JIS Z 8730) before and after heat treatment of the fluororesin laminated sheet woven fabric side when the fluororesin laminated sheet is heat-treated in a heating furnace at 300 ° C. for 5 hours. Is 2.0 to 6.0.

[0020] The present invention also provides a method in which a continuous heat-resistant base fabric and a continuous fluororesin sheet are superimposed on each other and continuously heated to one heating roll heated to a temperature equal to or higher than the melting point of the fluororesin of the fluororesin sheet. The present invention relates to a method for producing a fluororesin laminated sheet in which a supplied fluororesin sheet and a heat-resistant base fabric are continuously laminated, the method being characterized in that the fluororesin sheet is arranged on the side in contact with a heating roll.

The present invention further provides a heat-resistant base material, a continuous heat-fusible resin film, and a continuous fluororesin sheet laminated in this order at least above the melting point of the fluororesin of the fluororesin sheet. A method for producing a fluororesin laminated sheet, wherein the fluororesin sheet and a heat-resistant base fabric are continuously supplied to one heated roll being heated and continuously laminated through an adhesive layer of a heat-fusible resin. The present invention also relates to a production method characterized in that a fluororesin sheet is disposed on a side in contact with a heating roll.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The material of the fluororesin sheet used in the present invention may be a fluororesin having excellent chemical resistance and excellent heat resistance, such as polytetrafluoroethylene (PTFE) and tetrafluoroethylene (TFE). A copolymer (PFA) of perfluoro (alkylvinyliether) (PAVE) and a copolymer (FEP) of TFE and hexafluoropropylene (HFP) are preferred. In particular, PTFE is preferred from the viewpoint of excellent low permeability and stress crack resistance of the chemical solution, and the modified PTFE described below is preferable from the viewpoint of excellent void generation.

The modified PTFE is a copolymer of TFE and a small amount of another fluoromonomer, and has the property of PTFE that it cannot be melt-processed. Modified PTFE
The molar ratio of TFE to the other fluoromonomer in
95: 5 to 99.999: 0.001. Specific examples of the modified PTFE include PAVE-modified PTFE modified with PAVE and HFP modified with HFP.
FP-modified PTFE and the like. As PAVE, formula (I): CF ₂ ＣＦCF—OR _f (I) (wherein, R _f has a carbon atom and a fluorine atom as essential, does not have a hydrogen atom, and has an oxygen atom. Or an organic group which may be substituted).

The R _f group in the formula (I) has 1 to 1 carbon atoms.
0 perfluoroalkyl group, C 4-9 perfluoro (alkoxyalkyl) group, formula (II):

[0025]

Embedded image

Wherein m is an integer from 0 to 4, or formula (III):

[0027]

Embedded image

(Wherein, n is an integer of 0 to 4).

The modified PTFE preferably has a specific gravity of at least 2.13, more preferably at least 2.15, because of its low chemical permeability. Preferred modified PTFE is PAVE modified PTFE because of its excellent heat-fusibility.

Although the thickness of the fluororesin sheet is not particularly limited, a relatively thin one facilitates adhesion by heating. The preferred thickness is 0.2-2.0 mm, especially 0.2-1.0
mm, but is also applicable when the thickness of the fluororesin sheet is up to 5.0 mm.

The melting point of these fluororesins is PTFE
317-337 ° C (including denaturation), 300-
320 ° C, FEP 260-280 ° C.

The heat-resistant base fabric used in the present invention is a heat-resistant fiber woven fabric made of a material which is a heat-resistant fiber substantially containing no carbon element and which does not melt at a temperature at which the fluororesin sheet melts. Any knitted fabric can be used.

Examples of the heat-resistant fiber include glass fiber containing substantially no carbon element, various metal fibers, ceramic fiber (alumina (Al ₂ O ₃ ) fiber, and silicic anhydride (Si ₂ O ₂ ).
Fiber, boron nitride fiber, etc.), and other heat-resistant fibers such as carbon fiber, silicon carbide (SiC) fiber, and Tyranno (Tyranno: Si—Ti—C—O) are used in the production method of the present invention. ) Fibers, organic fibers (aramid fibers, liquid crystal polymer fibers, etc.) can also be used. In addition, heat resistance, affinity with fluororesin, transparency,
Glass fibers are preferred because they have excellent surface treatment properties and are inexpensive.

As described above, these heat-resistant fibers are treated with a sizing agent, and the woven or knitted fabric also contains the sizing agent. With the conventional fabric for fluororesin laminated sheet,
Although this sizing agent was removed as much as possible by heat treatment, the heat-resistant base fabric used in the present invention has a relatively large amount of the sizing agent remaining. If the residual amount of the sizing agent is large, the base fabric fibers do not shift or break when laminated with the fluororesin sheet, and the flexibility when the laminated sheet is formed is improved and the mechanical strength is increased. It will be easier.

The remaining amount (amount) of the sizing agent is determined by elementary analysis of the base cloth. According to this elemental analysis method, the residual amount of the sizing agent in the glass fiber base fabric used as the conventional heat-resistant base fabric for the fluororesin laminated sheet is less than 0.05% by weight of carbon element. The remaining amount of the sizing agent of the heat-resistant base fabric used in the present invention is 0.05 to
0.50% by weight, preferably 0.10 to 0.25% by weight
It is. When the content is less than 0.05% by weight, the strength and the flexibility are remarkably reduced as in the case of the conventional base cloth, and the lining may be broken at the time of construction. On the other hand, when the content exceeds 0.50% by weight, foaming is caused by the decomposition of the sizing agent during the production of the laminated sheet, resulting in poor appearance, or bubbles in the sheet to impair the performance such as chemical resistance. Since the remaining amount of the sizing agent in the base fabric in the fluororesin laminate sheet cannot be measured, the remaining amount of the sizing agent is the remaining amount of the heat-resistant base fabric before lamination. Although the amount of the sizing agent decreases when heat-laminated with the fluororesin sheet, the amount of the sizing agent decreases even if the base fabric is not directly heated as described below, compared to the conventional method of heating from the base fabric side. Since the amount is small, the amount of the sizing agent remaining in the fluororesin laminated sheet is clearly larger than that of the conventional fluororesin laminated sheet. This point will be clarified in the description of the color change after the heat treatment described later.

In the heat-resistant base fabric used in the present invention, the remaining amount of the sizing agent is important. After adjusting the amount of the carbon element in the above range, the treatment may be performed by a coupling agent treatment, a graft polymerization treatment, a plasma irradiation treatment, or the like. Those subjected to various surface treatments are included in the present invention. As the surface treatment, a surface treatment that does not reduce the strength of the base fabric and does not emit smoke during lamination by heating and improves the affinity with the fluororesin is preferable.

The heat-resistant base fabric is preferably a woven or knitted fabric of heat-resistant fiber, but a twill woven fabric having good flexibility and good drapability or a satin woven fabric having excellent flexibility and strength and a smooth surface. However, it is particularly preferable in terms of good strength and workability. In addition, woven fabric such as plain weave and roving cloth, knit (knitted fabric) and the like can also be used.

Although the number of fibers may be increased to increase the strength of the heat-resistant base fabric, the flexibility decreases as the number of fibers increases,
The thickness also increases. The thickness of the heat-resistant base fabric used in the present invention may be smaller than that of the conventional base fabric, and may be 0.1 to 0.5 m.
m, particularly preferably 0.2 to 0.3 mm.

The fluororesin laminated sheet of the present invention heats the fluororesin sheet and the heat-resistant base cloth to a temperature equal to or higher than the melting point of the fluororesin, and the surface of the fluororesin sheet on the base cloth side melts to form the base cloth. It is obtained by entering and forming a physical (mechanical) joint (so-called joint by an anchor effect).

At this time, between the fluororesin sheet and the base cloth,
As in the conventional case, the adhesive layer may be provided with a film made of a heat-meltable resin interposed therebetween. This adhesive layer functions to further strengthen the bonding between the fluororesin sheet and the base cloth.

The heat-fusible resin film may be any film that can be heat-fused to a fluororesin sheet, and may be an olefin resin having a melting point close to the melting point of the fluororesin sheet;
Aromatic resins such as PPS, PES, PEEK; TFE
Heat-fusible fluororesins such as -PAVE copolymer (PFA) and TFE-hexafluoropropylene copolymer (FEP). Among these, a hot-melt fluororesin having the same properties as the fluororesin used for the fluororesin sheet and having good adhesion to the fluororesin sheet,
In particular, PFA, FEP, etc., and particularly PFA are preferred.

This heat-fusible resin film may be used alone for producing a laminated sheet, or may be a laminate adhered to a fluororesin sheet. Further, a functional laminate in which a heat-fusible resin film is laminated on a fluororesin sheet may be used. Therefore, the thickness may be appropriately selected depending on the purpose, for example, about 10 to 300 μm.

Further, when a PTFE sheet having a large specific gravity is used as the fluororesin sheet, WO 00-108
As described in pamphlet No. 05, unfired P
By bonding the TFE fine particles between the fluororesin sheet and the heat-fusible resin film to form an unfired PTFE fine particle layer, the adhesive strength is further improved.

The thickness of the fluororesin laminate sheet of the present invention is as follows:
Depending on the thickness of each layer, from the viewpoint of workability, about 0.5
〜5.5 mm, preferably about 0.5-1.5 mm.

The fluororesin laminate sheet of the present invention is characterized in that the remaining amount of the sizing agent is larger than that of the conventional laminate. It is extremely difficult to directly and quantitatively measure the remaining amount of the sizing agent in the fluororesin laminated sheet. However, if the fluororesin laminated sheet is heat-treated at a temperature equal to or higher than the decomposition temperature of the sizing agent, the sizing agent in the laminated sheet is thermally decomposed and discolored, so that the laminated sheet is also discolored. Therefore, by observing the color that changes when the fluororesin laminated sheet is heat-treated under specific conditions, the fluororesin laminated sheet of the present invention can be specified.

That is, according to the present invention, a woven or knitted fabric of glass fiber treated with a sizing agent is used as a heat-resistant base fabric, and a fluororesin sheet is directly or via an adhesive layer made of a heat-meltable resin on the base fabric. A laminated sheet of fluororesin, which is subjected to a heat treatment in a heating furnace at 300 ° C. for 5 hours, before and after the heat treatment of the laminated sheet of fluororesin, the color difference of L ^* a ^* b ^* color system ΔE (JIS Z 8
730) is from 2.0 to 6.0, preferably from 3.0 to 6.0.
Also, the present invention relates to a fluororesin laminated sheet.

Since the color difference ΔE is an absolute value of the color difference, the value becomes large when the difference between the changes is large, even when the color changes darkly or brightly. In the present invention, it is preferable that L ^* changes greatly and a ^* b ^* changes little. The conventional fluororesin laminate sheet with a small amount of the remaining sizing agent has a small color difference ΔE of 0.5 or more and less than 2.0.

Next, the production method of the present invention will be described.

The production method of the present invention relates to a continuous production method of a fluororesin laminated sheet. When the fluororesin laminate sheet has a two-layer structure of a heat-resistant base cloth and a fluororesin sheet, the continuous heat-resistant base cloth and the continuous fluororesin sheet are superimposed on each other, and the melting point of the fluororesin sheet is higher than the melting point of the fluororesin. It is characterized in that the fluororesin sheet is disposed on the side in contact with the heating roll when the fluororesin sheet and the heat-resistant base fabric are continuously laminated by being continuously supplied to one heated roll.

For example, as schematically shown in FIG. 1, a roll 2 around which a continuous heat-resistant base cloth 1 is wound and a roll 4 around which a fluororesin sheet 3 is wound are each separated from a heat-resistant base cloth. The cloth 1 and the fluororesin sheet 3 are paid out, and are overlapped between the press roll 5 and the heating roll 6. At this time, the fluororesin sheet 3 is arranged so as to be in contact with the surface of the heating roll 6. The surface of the heating roll 6 is heated to a temperature equal to or higher than the melting point of the fluororesin sheet 3. Fluorine resin is modified PTFE (melting point: 327-3
45 ° C.), it is usually about 350 to 420 ° C.

The superposed fluororesin sheet 3 and the heat-resistant base fabric 1 are in contact with the heating roll 6 between the cooling roll 7 and
During this time, the fluororesin sheet at least partially melts and enters the fibers of the heat-resistant base fabric.

The fluororesin laminated sheet 8 of the fluororesin sheet 3 and the heat-resistant base fabric 3 thus melt-bonded is taken up by a take-up roll 9 while being cooled.

Unlike the conventional heating from the heat-resistant base fabric side, according to the manufacturing method of the present invention, the fluororesin sheet 3 is in contact with the heating roll 6 and the heat-resistant base fabric 1 holds down the fluororesin sheet 3. Therefore, an appropriate tension can be applied to the fluororesin sheet 3, so that generation of wrinkles and waving in the width direction can be suppressed, and a wide fluororesin laminated sheet can be manufactured.

When the fluororesin laminate sheet has a three-layer structure of a heat-resistant base cloth, a heat-fusible resin adhesive layer and a fluororesin sheet, as shown in FIG. , A continuous fusible resin film 10 from the roll 11 and a continuous fluororesin sheet 3 from the roll 4 are fed, and the pressing roll 5 and the heating roll 6 are superposed in this order, and at least the fluororesin sheet The fluororesin sheet 3 and the heat-fusible resin film 10 are melted by being continuously supplied to one heating roll 6 heated to a temperature higher than the melting point of the fluororesin while the fluororesin sheet 3 is in contact with the heating roll 6. The cloth 1 and the fluororesin sheet 3 are continuously laminated via an adhesive layer of a heat-fusible resin, and a three-layer fluororesin laminated sheet 12
Is wound up on a winding roll 9.

In the method for manufacturing a three-layered fluororesin laminated sheet, the fluororesin sheet 3 is
Since the fluororesin sheet 3 is held down by the heat-resistant base cloth 1 during heating and melting, wrinkling and waving can be suppressed, and a wide fluororesin laminated sheet can be manufactured.

The fluororesin laminate sheet of the present invention is suitable for the following uses, for example. Lining materials: Smoke exhaust duct lining, drainage pit lining, painting booth lining, anti-corrosion of common ditch
Insulation lining, corrosion prevention of concrete inside tunnel (mainly corrosion prevention by exhaust gas) lining, lining inside reaction tower, lining inside reaction tank, lining inside storage tank, lining inside transport tanks, inside liquid container Lining, inner lining of containers for chemicals and electronic equipment, lining of kitchen equipment, lining of waste disposal equipment, waterproof lining of buildings, etc. Joint materials: flexible joints such as smoke exhaust ducts, etc. Interior materials: vehicles, ships, aircraft Etc., interior materials for large buildings and houses, etc. Others: printed wiring boards, cooking sheets, release sheets, etc.

[0057]

EXAMPLES Next, the fluororesin laminate sheet of the present invention will be described based on examples, but the present invention is not limited to only these examples.

Example 1 Using a laminating apparatus shown in FIG. 2, a fluororesin laminated sheet having a three-layer structure was produced. Twill woven glass cloth (thickness: 0.31%) having a carbon element content of 0.11% by weight as a heat-resistant base cloth.
mm) as PAVE-modified PTF as a fluororesin sheet
An E sheet (melting point: 327 ° C., thickness 0.5 mm) was used as a hot-melt resin film as a PFA film (melting point: 310).
° C, thickness 100 µm). The surface temperature of the heating roll was set at 370 ° C., the sheet was passed over the heating roll at a winding speed of 0.4 m / min, and wound on the winding roll.

The remaining amount of the sizing material of the glass cloth is C
HN elemental analyzer (MTA-33 manufactured by Yanagimoto Co., Ltd.)
0).

Regarding the obtained fluororesin laminated sheet,
The mechanical strength (JIS K6891) and the presence or absence of wrinkles were examined. Table 1 shows the results.

After the fluororesin laminated sheet was heated in a hot air circulating electric furnace at 300 ° C. for 5 hours, a color difference meter (SM color computer MODEL manufactured by Suga Test Instruments Co., Ltd.) was used.
According to SM-7), the color difference ΔE was measured according to JIS Z 8730. Table 1 shows the results.

Comparative Example 1 In Example 1, the heat-resistant base fabric had a carbon element content of 0.1%.
Twill weave glass cloth (thickness 0.3m)
A fluororesin laminated sheet was prepared in the same manner except that m) was used, and the mechanical strength, the presence or absence of wrinkles, and the color difference ΔE were measured. Table 1 shows the results.

Example 2 In Example 1, a fluororesin sheet having a thickness of 3.0 was used.
Using a PAVE-modified PTFE sheet having a thickness of 2 mm, a fluororesin laminated sheet was prepared in the same manner except that the heating roll surface temperature was set to 400 ° C., and the mechanical strength, the presence or absence of wrinkles, and the color difference ΔE were measured. Table 1 shows the results.

Example 3 In Example 1, the thickness of the fluororesin sheet was 2.4.
Using a PAVE-modified PTFE sheet having a thickness of 2 mm, a fluororesin laminated sheet was prepared in the same manner except that the heating roll surface temperature was set to 400 ° C., and the mechanical strength, the presence or absence of wrinkles, and the color difference ΔE were measured. Table 1 shows the results.

COMPARATIVE EXAMPLE 2 In Example 1, the amount of carbon element was set to 0.
04% by weight satin-woven glass cloth (thickness 0.3m
A fluororesin laminated sheet was prepared in the same manner except that m) was used, and the mechanical strength, the presence or absence of wrinkles, and the color difference ΔE were measured. Table 1 shows the results.

[0066]

[Table 1]

COMPARATIVE EXAMPLE 3 In Example 1, the heat-resistant base fabric had a carbon element content of 0.
57% by weight twill glass cloth (0.3m thick
An attempt was made to produce a fluororesin laminate sheet in the same manner except that m) was used, but the production was stopped because smoke was generated on the heating roll.

Comparative Example 4 In Example 1, the positions of the fluororesin sheet and the glass cloth were reversed by using the laminating apparatus shown in FIG. 2, and the heating cloth was brought into contact with the glass cloth so that the base cloth (glass cloth) side was used. When a fluororesin laminate sheet was prepared in the same manner except that the sheet was heated from the beginning, wrinkles were generated.

[0069]

The fluororesin laminate sheet of the present invention is excellent in both flexibility and strength, so that it can be easily installed on site and can follow the lining surface firmly. ) Can be prevented from rising early, and the durability is high.

[Brief description of the drawings]

FIG. 1 is a schematic diagram for explaining a production method of the present invention.

FIG. 2 is a schematic view for explaining another manufacturing method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Heat resistant base fabric 2 Roll 3 Fluororesin sheet 4 Roll 5 Pressing roll 6 Heating roll 7 Cooling roll 8 Fluororesin laminated sheet 9 Winding roll 10 Heat-fusible resin film 11 Roll 12 Fluororesin laminated sheet

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Yasuhiro Sakamoto 1-1, Nishi-Itsuya, Settsu-shi, Osaka Daikin Industries, Ltd. F-term in Yodogawa Works 4F100 AG00B AK17A AK17G AK17J AK18A AL01A AL01G BA02 CB03 DG01B DG12B DG12K DG13B DG13K EJ192 EJ422 EJ64B GB07 GB51 GB90 JA13A JJ03B JK01 JK13 JK17 JL00 JL10 YY00A YY00B 4F211 AA16 AC03 AD16 AG01 AG03 TA04 TC05 TD11 TJ11 TN09 TN48 TQ03

Claims (15)

[Claims] 1. A woven or knitted fabric of a heat-resistant fiber sizing agent-treated fiber substantially containing no carbon element, wherein the remaining amount of the sizing agent is 0.05 to 0.50% by weight in terms of carbon element. A woven or knitted fabric as a heat-resistant base fabric, and a fluororesin sheet laminated directly on the base fabric. 2. A woven or knitted fabric of a heat-resistant fiber sizing agent-treated fiber substantially containing no carbon element, wherein the remaining amount of the sizing agent is 0.05 to 0.50% by weight of carbon element. A woven or knitted fabric as a heat-resistant base fabric, and a fluororesin sheet laminated on the base fabric via an adhesive layer made of a heat-fusible resin. 3. The fluororesin laminated sheet according to claim 1, wherein the heat-resistant base fabric is a woven or knitted fabric of glass fiber. 4. The heat-resistant base fabric is a glass fiber woven or knitted fabric, and before and after heat treatment of the fluororesin laminated sheet when the fluororesin laminated sheet is heat-treated in a heating furnace at 300 ° C. for 5 hours. The fluororesin laminate sheet according to claim 3, wherein the color difference ΔE (JIS Z 8730) is 2.0 to 6.0. 5. A woven or knitted fabric of glass fiber treated with a sizing agent is used as a heat-resistant base fabric, and a fluororesin sheet is laminated on the base fabric directly or via an adhesive layer made of a heat-meltable resin. And a color difference ΔE (JIS Z 8730) before and after heat treatment on the woven side of the fluororesin laminated sheet when the fluororesin laminated sheet is heat-treated in a heating furnace at 300 ° C. for 5 hours. And a fluororesin laminate sheet having a thickness of from 6.0 to 6.0. 6. The fluororesin laminated sheet according to claim 1, wherein the heat-resistant woven fabric is a twill or satin woven fabric. 7. The fluororesin laminated sheet according to claim 1, wherein the thickness of the woven fabric is 0.2 to 0.5 mm. 8. The sheet according to claim 1, wherein the fluororesin sheet is a sheet of polytetrafluoroethylene, tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer or tetrafluoroethylene-hexafluoropropylene copolymer. The fluororesin laminated sheet according to the above item. 9. The fluororesin laminated sheet according to claim 1, wherein the fluororesin sheet is a modified polytetrafluoroethylene sheet. 10. The layer thickness of the fluororesin sheet is 0.2
The fluororesin laminate sheet according to any one of claims 1 to 9, which has a thickness of from 2.0 to 2.0 mm. 11. The fluororesin laminated sheet according to claim 9, wherein the layer of the fluororesin sheet is a layer of a modified polytetrafluoroethylene sheet having a specific gravity of 2.13 or more. 12. The fluororesin laminate sheet according to claim 2, wherein the heat-fusible resin constituting the adhesive layer is a tetrafluoroethylene-perfluoro (alkyl vinyl ether) copolymer. 13. A continuous heat-resistant base fabric and a continuous fluororesin sheet are superposed and continuously supplied to one heating roll heated to a melting point of the fluororesin of the fluororesin sheet or higher. What is claimed is: 1. A method for producing a fluororesin laminated sheet, comprising continuously laminating a fluororesin sheet and a heat-resistant base cloth, wherein the fluororesin sheet is disposed on a side in contact with a heating roll. 14. A continuous heat-resistant base fabric, a continuous hot-melt resin film, and a continuous fluororesin sheet are superposed in this order, and are heated to at least the melting point of the fluororesin of the fluororesin sheet. A method of manufacturing a fluororesin laminated sheet in which a fluororesin sheet and a heat-resistant base fabric are continuously supplied to one heating roll and continuously laminated through an adhesive layer of a heat-fusible resin. A method for producing a fluororesin laminated sheet, comprising: arranging a fluororesin sheet on a contacting side. 15. The production method according to claim 13, wherein the obtained fluororesin laminated sheet is the fluororesin laminated sheet according to any one of claims 1 to 12.