JP2000085056A - Manufacture of chemical-resistant sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a means to prevent the waviness and creases of a chemical-resistant sheet from occurring and improve the surface smoothness of a sheet base material side in a method for manufacturing a chemical-resistant sheet obtained by joining the sheet base material of polytetrafluoroethylene resin with glass cloth into one piece through a melt fluid fluororesin layer using a continuous technique. SOLUTION: A sheet base material 1, film 2 of a melt fluid fluororesin and glass cloth 3 are laminated in such a manner that the film 3 is sandwiched in between by paying off the described materials 1, 2, 3 continuously from winding rolls R1-R3. Further the laminate is thermally contact-bonded by making it pass through gaps between a high temperature roll H1 whose surface temperature is higher than the melt point of the fluororesin of the film 3 and low temperature rolls C1, C2 which have a lower surface temperature than the melt point and form nip parts 4a, 4b with the high temperature roll H1 respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a lining material such as a reaction tower, a reaction tank, a storage tank, a tank for transportation and storage, a container for liquid, a container for chemicals and electronic parts, and a vehicle, a ship, and the like. The present invention relates to a method for manufacturing a chemical-resistant sheet having weather resistance, heat resistance, and the like suitable as interior materials for aircraft, public facilities, houses, and the like.

[0002]

2. Description of the Related Art Fluorine-based resins are excellent in chemical resistance, heat resistance, non-adhesiveness, electrical properties, etc., and are used in various industries such as chemicals, petroleum, paints, inks, industrial chemicals, pharmaceuticals, and semiconductors. Widely used in the field. However, a typical fluororesin, polytetrafluoroethylene resin (hereinafter abbreviated as PTFE), has a poor surface activity and cannot be adhered by ordinary means and does not melt and flow. When used for the interior of tanks, etc., in the past, the so-called loose lining method of simply interposing the sheet between the vessel wall and the contents, or the adhesive side surface of the sheet was activated by mechanical or chemical treatment. The method of lining via an adhesive was adopted after the formation, but the former method has great restrictions on the application, and the latter method has insufficient bonding strength and the fragility of the sheet itself. There is a problem in use and processing due to.

[0003] In view of the above, the present applicant has first developed a laminated chemical resistant sheet using PTFE, and continuously bonded this long sheet to a long sheet by heating and pressing between a pair of heat rolls. (Japanese Patent Publication No. 8-18410). As shown in FIG. 5, this chemical-resistant sheet has a thermoplastic (melt fluidity) fluororesin film interposed between a sheet substrate made of PTFE and a glass cloth, and is heated and pressed to form an integrated laminate. The glass cloth side is used as the bonding surface, and it can be bonded with high strength to the walls of various materials with ordinary adhesive, and the sheet itself is tough due to the laminated structure with the glass cloth. Due to its advantages, it is already used in a wide range of industrial fields. In particular, long objects produced by the above manufacturing method
Since it can be used after being cut into an appropriate length according to the size of the portion to be lined or the like, a large amount of unused short material due to a surplus portion does not occur, and waste is reduced and economical.

[0004]

However, the chemical-resistant sheet obtained as a long product by the above-mentioned continuous production method often has a wavy overall or a partial wrinkle. It is an issue to prevent quality deterioration due to these, and there is still room for improvement in the smoothness of the surface on the sheet substrate side.

[0005] In view of the above-mentioned circumstances, the present inventors have proposed a PT
For the same chemical resistant sheet as described above in which the FE sheet base material and the glass cloth are integrally laminated via a melt-flowable fluororesin film, a high-quality sheet free of waving and wrinkles is stably obtained by a continuous method. To determine the means,
First, the factors that cause the sheet to undulate or wrinkle in the conventional continuous manufacturing method were examined in detail. As a result, in the process until the laminated sheet integrated by the heat compression between the heat roll pair is finally wound up, the temperature of the laminated sheet heated by the heat compression is gradually lowered by natural cooling. However, since the cooling progresses faster on both sides than in the center in the sheet width direction, it has been found that the sheet has waving and wrinkles due to the difference in the degree of shrinkage caused by the temperature gradient in the sheet width direction.

[0006]

Therefore, as a result of further intensive studies based on the above findings, in order to prevent the above-mentioned sheet from waving or wrinkling, the laminated sheet during or immediately after the heat and pressure bonding is used as a sheet base. It is very effective to actively cool from the material side and uniformly over the entire sheet width direction, and it is preferable to use a low-temperature roll as this cooling means. The present inventors have found that the surface smoothness can be improved, and have accomplished the present invention.

That is, the method for producing a chemical-resistant sheet according to claim 1 of the present invention is, as shown by reference numerals in the drawings, a sheet substrate 1 made of PTFE (polytetrafluoroethylene) resin, The film 2 made of a fluorine-based resin having melt fluidity and the glass cloth 3 are continuously fed out from each of the winding rolls R1 to R3, and are superposed so that the film 3 is interposed therebetween. Roll H whose roll surface temperature is higher than the melting point of the fluororesin of the film 3 while continuously running
The sheet base material 1 is passed between the low-temperature rolls C1 and C2 constituting the nip portions 4a and 4b with respect to the high-temperature roll H1 having a roll surface temperature lower than the same melting point and heat-pressed to thereby form the sheet base 1 Sheet 11 in which glass cloth 2 and glass cloth 2 are integrated via molten resin layer 30 of film 3
It is characterized by the following.

[0008] According to the above configuration, the continuously running superposed sheet 10 includes the high-temperature roll H1 and the low-temperature rolls C1 and C1.
2 when passing through the nip portions 4a and 4b with the high-temperature roll H
The heat from 1 melts and fluidizes the fluororesin of the film 3 and adheres to the sheet substrate 1 made of PTFE having a high affinity because it is also a fluororesin, and enters between the fibers of the glass cloth 2. The laminated sheet 11 in which the sheet substrate 1 and the glass cloth 2 are firmly integrated via the resin layer 30 of the film 3 is obtained. Thus, the laminated sheet 11 (the superposed sheet 10) has the nip portions 4a,
4b, heat is uniformly and rapidly removed in the sheet width direction by heat absorption from one side by the low-temperature rolls C1 and C2, so that the sheet base 1 does not reach an overheated state. The surface roughness is prevented, and uniform shrinkage occurs in the sheet width direction with this cooling. However, at a stage away from the nip portion 4b, the temperature has already been lowered and almost no shrinkage has been achieved.

[0009] In the manufacturing method of claim 1,
According to the second aspect of the present invention, if the laminated sheet 11 is passed between the high-temperature roll H1 and the low-temperature rolls C1 and C2 so that the surface on the glass cloth 2 side is in contact with the high-temperature roll H1, the sheet The surface on the substrate 1 side is a low-temperature roll C
1 and C2, so that the surface roughness of the outer sheet substrate 1 is more reliably prevented.

In a third aspect of the present invention, there is provided a method for manufacturing a chemical-resistant sheet, comprising: a sheet substrate 1 made of PTFE, a film 3 made of a fluorine-based resin having melt fluidity, and a glass cloth 2. The film 3 is continuously fed out from the winding rolls R1 to R3 and overlapped so that the film 3 is sandwiched in the middle, and the roll surface temperature is higher than the melting point of the fluororesin of the film 3 while continuously running the overlapped sheet 10. The sheet is passed between a pair of high-temperature rolls H2 and H3 and heat-pressed, and immediately after the heat-pressing, at least the surface of the sheet substrate 1 is brought into contact with the peripheral surface of the low-temperature rolls C2 and C5 whose roll surface temperature is lower than the melting point. By letting
The present invention is characterized in that the sheet base 1 and the glass cloth 2 are formed into a laminated sheet 11 which is integrated via a molten resin layer 30 of the film 3.

According to the structure of the third aspect, the continuous running superposed sheet 10 is heated and pressed between the pair of high-temperature rolls H2 and H3, so that the fluorine-based resin of the film 3 is melted and fluidized. As in the manufacturing method of claim 1, the laminated sheet 11 in which the sheet base material 1 and the glass cloth 2 are firmly integrated via the molten resin layer 30 of the film 3 becomes a high temperature immediately after thermocompression bonding. Laminated sheet 11
At least the surface of the sheet substrate 1 side is a low-temperature roll C3.
By contacting with C5, heat is uniformly and rapidly taken away in the sheet width direction. Even if uniform shrinkage occurs in the sheet width direction due to this cooling, since the temperature has already been lowered, almost all shrinkage occurs. In addition, due to the contact with the low-temperature rolls C3 to C5, the surface roughness of the sheet substrate 1 is repaired and the sheet substrate 1 is smoothed.

[0012] In the above-mentioned manufacturing method of claims 1 to 3,
The roll surface of the high-temperature rolls H1 to H3 as in the invention of claim 4, in order to surely exert the melting action of the fluororesin of the film 2 by the high-temperature rolls H1 to H3 and the cooling action by the low-temperature rolls C1 to C5. It is recommended that the temperature be set at least 50 ° C. higher than the melting point of the fluororesin of the film 2 and the roll surface temperature of the low-temperature rolls C1 to C5 be set at least 50 ° C. lower than the melting point. Also,
In the manufacturing method according to any one of claims 1 to 4, from the viewpoint of sheet properties as a chemical-resistant sheet and the melting action and the cooling action, as in the invention of claim 5, the thickness of the sheet substrate 1 is 0.2 to 0.2. 5 mm, thickness of the film 3 is 0.05 to 0.2
mm, the thickness of the glass cloth 2 is preferably 0.2 to 2 mm.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for producing a chemical resistant sheet according to the present invention will be specifically described with reference to the drawings. 1 to 5 show a configuration example of a continuous manufacturing apparatus to which the manufacturing method of the present invention is applied. In these figures, R1 is a winding roll of a sheet substrate 1 made of PTFE, and R2 is a glass cloth 2
R3 is a winding roll of the film 3 made of a fluorine resin having melt flowability, H1 to H3 are high temperature rolls whose roll surface temperature is set higher than the melting point of the fluorine resin of the film 3, C1 C5 is a non-heated low-temperature roll, 5A and 5B are front guide rolls forming a roll pair, 6
Denotes a rear guide roll, and 7 denotes a winding roll.

In the apparatus configuration of FIG. 1, one hot roll H
The two low-temperature rolls C1 and C2 form nip portions 4a and 4b in front of and behind the winding rolls R1 to R3.
The sheet base 1 and the glass cloth 2 and the film 3 wound as a long object are continuously fed out in synchronization with each other, and pass between the front guide rolls 5A and 5B with the film 3 sandwiched in the middle. The superposed sheet 10 is continuously moved, and the surface on the glass cloth 2 side is heated between two nip portions 4a and 4b before and after the high-temperature roll H1 and the low-temperature rolls C1 and C2. The sheet is passed while being in contact with the peripheral surface of the roll H <b> 1, and is heat-pressed and continuously wound as a laminated sheet 11 on a take-up roll 7 via a rear guide roll 6.

In this manufacturing process, the continuously running laminated sheet 10 is composed of a high-temperature roll H1 and two low-temperature rolls C.
1 and C2, the fluororesin of the film 3 sandwiched in the middle is melted and fluidized by heat from the high-temperature roll H1, and is made of PTFE having good affinity because it is also a fluororesin. While being in close contact with the sheet substrate 1, it penetrates between the fibers of the glass cloth 2, whereby the sheet substrate 1 and the glass cloth 2 are firmly bonded via the melted and solidified resin layer 30 of the intermediate film 3 as shown in FIG. The laminated sheet 11 is integrated with the sheet.

In the front and rear nip portions 4a and 4b, the surface of the laminated sheet 11 (laminated sheet 10) on the sheet substrate 1 side is in contact with the low-temperature rolls C1 and C2, and the heat generated by these low-temperature rolls C1 and C2. Because of the absorption, the sheet substrate 1 does not overheat, thereby preventing the surface of the sheet substrate 1 from being roughened. In addition, especially at the rear nip portion 4b, the laminated sheet 11 undergoes uniform shrinkage in the sheet width direction as it is cooled by the low-temperature roll C2. Owing to the difference in expansion and contraction caused by the temperature gradient in the sheet width direction at the time of cooling. Therefore, the obtained laminated sheet 11, that is, the chemical-resistant sheet, is extremely excellent in flatness, and has a smooth surface having a high surface luminance on the sheet substrate 1 side.

In the above-described manufacturing process, the heat-compression-bonded portion is provided with two low-temperature rolls C1 and one high-temperature roll H1.
Although the nip portions 4a and 4b are formed before and after C2, the nip portion is formed by one high-temperature roll H1 and one low-temperature roll. A configuration in which three or more low-temperature rolls forming a part are arranged can also be adopted. However, in the former configuration in which one low-temperature roll is used, in order to reliably melt the film 2 at the time of thermocompression bonding, it is possible to avoid a situation in which the film 2 does not melt at the time of thermocompression bonding due to supercooling from the low-temperature roll side. For this reason, it is desirable to control the film 2 at the time of thermocompression bonding to surely reach the melting point or higher by means such as providing a heating mechanism on the low-temperature roll side. In the latter configuration in which the number of low-temperature rolls is three or more, each low-temperature roll has a small diameter and a small heat radiation area in order to form a nip portion with respect to one high-temperature roll 3. It is desirable to provide an active cooling mechanism in order to suppress the temperature rise of each low-temperature roll due to the heat transfer to a certain temperature or less.

In the apparatus configuration of FIG. 2, two hot rolls H
2, H3 forms a pair of rolls, and the low-temperature roll C3 is independently disposed immediately after the pair of rolls, and the sheet base 1 and the glass cloth which are continuously fed out in synchronization with the winding rolls R1 to R3. 2 and the film 3 are passed through the front guide rolls 5A and 5B in the same manner as described above to form a laminated sheet 10, which is passed between a pair of high-temperature rolls H2 and H3 and heated and pressed to form a laminated sheet 11. Immediately after the thermocompression bonding, the sheet base 1 side of the laminated sheet 11 is brought into contact with the low-temperature roll C3,
Through the winding roll 7 continuously.

In this manufacturing process, the continuously running laminated sheet 10 is heated and pressed between the pair of high-temperature rolls H2 and H3, so that the fluororesin of the film 3 melts and flows, and the sheet Sheet 11 in which glass cloth 2 and glass cloth 2 are integrated via film 3 (see FIG. 5)
However, when the surface of the high-temperature laminated sheet 11 on the side of the sheet substrate 1 immediately after the thermocompression bonding is in contact with the low-temperature roll C3, the heat is uniformly and rapidly removed in the sheet width direction to cool the sheet. I do. Accordingly, uniform shrinkage occurs in the sheet direction with this cooling, but since the temperature has already been lowered at a stage away from the low-temperature roll C3 and the shrinkage has been almost lost, the temperature in the sheet width direction at the time of cooling has been reduced. The generation of waviness and wrinkles due to the gradient is avoided. Also, even if the surface of the sheet substrate 1 is roughened at the stage when the superposed sheet 10 has passed between the pair of high-temperature rolls H2 and H3, the surface of the PTFE in the high temperature state on the sheet substrate 1 side has a low temperature. By directly contacting the low-temperature smooth surface of the roll C3, the surface roughness is repaired. Therefore, the obtained chemical-resistant sheet also has excellent flatness and good surface smoothness on the sheet substrate 1 side.

In the apparatus configuration shown in FIG.
One low-temperature roll C3 is arranged immediately after the pair of rolls H2 and H3, but two low-temperature rolls C forming a pair of rolls immediately after the high-temperature rolls H2 and H3 as shown in FIG.
If C3 and C4 are arranged and the laminated sheet 11 immediately after the heat-compression bonding is set to pass through this roll pair, the flatness and the surface smoothness of the sheet can be further improved by the improvement of the cooling efficiency and the pinching effect. . Further, as shown in the apparatus configuration shown in FIG. 4, one of the high-temperature rolls H2 and H3 is
5 are arranged so as to form a nip portion.
2, so that the laminated sheet 11 passing between the pair of H3 and the pair of the high-temperature roll H2 and the low-temperature roll C5 subsequently passes through the surface of the sheet substrate 1 side in contact with the low-temperature roll C5. Is also possible.

Although the roll surface temperature of the high-temperature rolls H1 to H3 is set higher than the melting point of the fluororesin of the film 3 as described above, in order to surely melt and fluidize the fluororesin, It is preferable to set the temperature higher than the melting point by 50 ° C. or more. Further, since the low-temperature rolls C1 to C5 have a temperature rise due to heat transfer during continuous operation even when the non-heated rolls are used as described above, the roll surface temperature must be set to ensure that the heat absorbing action is exhibited. 5 points higher than the melting point of fluororesin
It is preferable to set the temperature to be lower than 0 ° C. In particular, in the case of forming a nip portion with the high-temperature rolls H1 and H2 and having a large heat transfer amount, such as the low-temperature rolls C1 and C2 in FIG. 1 and the low-temperature roll C5 in FIG. 4, the roll surface temperature is set low as described above. Above, it is desirable to increase the roll diameter to enhance heat dissipation or to promote heat exhaustion by heat conduction from the bearing. If necessary, provide an appropriate cooling mechanism to actively exhaust heat. Is also good.

The melt-flowable fluororesin used for the film 3 is not particularly limited.
Copolymer of ₂ = CF ₂ and CF ₂ = CF-CF ₃ (Teflon FE, trade name of E.I.
P), CF ₂ = CF ₂ and CF ₂ = a copolymer of CF-ORf (Rf is a perfluoroalkyl group: the Teflon PF
A), a copolymer of CH ₂ = CH ₂ and CF ₂ = CF ₂ (same Teflon ETFE, trade name Tefzel of Du Pont-Mitsui Fluorochemicals Co., Ltd.), a polymer of CH ₂ = CF ₂ (polyvinylidene fluoride resin: same Teflon PVDF, Pennwa
It's trade name Kainer), CH ₂ = CH ₂ and CF ₂ =
CCIF copolymer (Teflon ECTFE), CHF
= CH ₂ polymer (Teflon PVF) and the like,
Among them, CF ₂ = CF ₂ and CF ₂ = CF-C
Copolymer of F ₃ (Teflon FEP), and CF ₂ =
Copolymer of CF ₂ and CF ₂ = CF-ORf (Teflon P
FA) is preferred.

Here, the thickness of the PTFE sheet substrate 1 is in the range of 0.2 to 5 mm, the thickness of the film 2 made of a fluorine-based resin having melt fluidity is in the range of 0.05 to 0.2 mm, The thickness of the glass cloth 3 is preferably in the range of 0.2 to 2 mm.

That is, the thickness of the sheet substrate 1 is 0.2 m
If it is less than 5 m, the characteristics of PTFE cannot be sufficiently exhibited as a lining material. On the contrary, if it exceeds 5 mm, it becomes difficult to wind it as a sheet due to its large rigidity. It becomes difficult to apply the manufacturing method. If the thickness of the film 2 is less than 0.05 mm or the thickness of the glass cloth 3 exceeds 2 mm, the adhesive strength between them becomes insufficient, and conversely, the thickness of the film 2 becomes 0.2 mm. When the thickness of the glass cloth 3 is less than 0.2 mm, the fluororesin of the film 3 melted at the time of heat-compression bonding penetrates to the surface of the glass cloth 3 to reduce the adhesiveness in the lining. Become. Thus, the press nip pressure between the high-temperature roll H1 and the low-temperature rolls C1 and C2 in FIG.
The press nip pressure between the high-temperature rolls H2 and H3 in 4 is preferably about 1 to 5 kg / cm in order to appropriately bite the melt-fluidized fluororesin into the glass cloth 3.

The laminated sheet 11 thus obtained, that is, the chemical-resistant sheet, can be easily provided with an adhesive lining on the walls of towers, tanks, etc. using a general adhesive on the glass cloth 2 side. As well as sheet substrate 1
PTFE can exhibit very high chemical resistance, heat resistance, non-adhesiveness, electrical properties, etc. on the surface on the side, and has excellent flatness without ripples and wrinkles on the sheet, and a good surface on the sheet substrate 1 side The sheet base 1 and the glass cloth 2 are of high quality with smoothness, and the resin layer 30 of the film 3
There is no fear of peeling off even under severe use conditions because of strong bonding. In addition, since this chemical-resistant sheet is obtained as a long product, it can be used by cutting it to an appropriate length according to the size of the part to be lined, etc. It does not generate a large amount of unused short wood due to a surplus portion unlike the conductive sheet, and is very economical with little waste.

[0026]

EXAMPLE 1 In the apparatus configuration shown in FIG. 1, a high-temperature roll H1 having a roll surface made of hard chrome plating and having a diameter of 250 mm, and a non-heated low-temperature roll C1 having a roll surface made of hard chrome plating and having a diameter of 220 mm were used. C2 and both low-temperature rolls C
The distance between the axes of C1 and C2 is 380 mm, and the nip portions 4a and 4b
And the roll surface temperature of the high-temperature roll H1 during continuous operation was controlled at 380 ° C., and the roll surface temperature of both low-temperature rolls C1 and C2 was controlled at 180 to 200 ° C. during continuous operation. While thickness 2
mm of PTFE and a thickness of 0.65 mm
mm of glass cloth 2 and a film 3 of Teflon PFA having a thickness of 0.125 mm are continuously fed out from winding rolls R1 to R3 having the same width, and are passed through the front guide rolls 5A and 5B and overlapped. , This is 200
While continuously feeding at a rate of mm / min, the sheet was hot-pressed through both nip portions 4a and 4b to continuously produce a long chemical-resistant sheet. This chemical-resistant sheet had no flatness and no wrinkles, was extremely excellent in flatness, and had a smooth surface on the sheet substrate 1 side and high surface brightness.

Example 2 In the apparatus configuration shown in FIG. 2, high-temperature rolls H2 and H3 having a diameter of 250 mm and a roll surface made of hard chromium plating were used.
220mm diameter roll surface is made of hard chrome plating
And the high-temperature roll H using the unheated low-temperature roll C3
2, the distance between the nip portion of H3 and the contact center position of the low-temperature roll C3 was set to 380 mm, the press nip pressure of both high-temperature rolls H2, H3 was set to 2.5 kg / cm, and the high-temperature rolls H2, H3 during continuous operation were set. While controlling the roll surface temperature to 380 ° C., a sheet substrate 1 made of PTFE having a thickness of 3 mm and a glass cloth 2 having a thickness of 0.65 mm
And a film 3 made of Teflon PFA having a thickness of 0.125 mm are continuously unwound from winding rolls R1 to R3 having the same width, and are passed through the front guide rolls 5A and 5B and overlapped. Hot press through the pair of the high-temperature rolls H2 and H3 while continuously feeding in minutes, and then contact the surface on the sheet substrate 1 side with the low-temperature roll C3 to continuously produce a long chemical-resistant sheet. . The roll surface temperature of the low-temperature roll C3 during continuous operation is 1
It was maintained at 80-200 ° C. The obtained chemical-resistant sheet had no flatness or wrinkles, was extremely excellent in flatness, and had a smooth surface on the sheet substrate 1 side and high surface brightness.

[0028]

According to the first aspect of the present invention, chemical resistance is obtained by integrally laminating a PTFE sheet and a glass cloth with a melt-flowable fluororesin layer interposed therebetween. In producing a sheet by a continuous method, a laminated sheet of each material is formed between a high-temperature roll having a roll surface temperature higher than the melting point of the fluororesin of the film and a low-temperature roll having a roll surface temperature lower than the melting point. Since it is heat-pressed through the nip portion, it is possible to obtain a very high-quality chemical-resistant sheet having a very flat surface without ripples and wrinkles and having excellent surface smoothness on the sheet substrate side as a long product. it can.

According to the second aspect of the present invention, in the above-described manufacturing method, the laminated sheet is passed in such a manner that the surface on the glass cloth side is in contact with the high-temperature roll, so that the surface roughness on the sheet substrate side is reliably prevented. Thus, there is an advantage that a chemical-resistant sheet having more excellent surface smoothness can be provided.

According to the third aspect of the present invention, when manufacturing the same chemical resistant sheet as in the first aspect by a continuous method, the roll surface temperature of the laminated sheet of each material is set to the melting point of the fluororesin of the film. Since it is passed between a pair of higher-temperature high-temperature rolls and heat-pressed, and immediately after this heat-pressure-bonding, at least the surface of the sheet substrate side is brought into contact with the peripheral surface of the non-heated low-temperature roll. Thus, a very high-quality chemical-resistant sheet having extremely excellent flatness and excellent surface smoothness on the sheet substrate side can be obtained as a long product.

According to the fourth aspect of the present invention, in each of the above manufacturing methods, the roll surfaces of the high-temperature roll and the low-temperature roll are set to a specific temperature difference with respect to the melting point of the fluororesin of the film. There is an advantage that a chemical resistant sheet having excellent flatness and surface smoothness on the sheet substrate side can be more reliably manufactured by a continuous method.

According to the fifth aspect of the present invention, in each of the above-described manufacturing methods, the thickness of the sheet substrate, the glass cloth, and the film are set in a specific range. And an advantage that properties suitable as a chemical resistant sheet can be imparted.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing a first configuration example of a continuous manufacturing apparatus to which a method for manufacturing a chemical resistant sheet according to the present invention is applied.

FIG. 2 is a schematic side view showing a second configuration example of the continuous manufacturing apparatus.

FIG. 3 is a schematic side view showing a third configuration example of the continuous manufacturing apparatus.

FIG. 4 is a schematic side view showing a fourth configuration example of the continuous manufacturing apparatus.

FIG. 5 is a sectional view of the chemical resistant sheet.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet base material 2 Glass cloth 3 Film 4a, 4b Nip part 5A, 5B Guide roll 6 Guide roll 7 Take-up roll 10 Laminated sheet 11 Laminated sheet H1-H3 High-temperature roll C1-C5 Low-temperature roll R1-R3 Winding roll

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Hirotaka Michishita 5-8-30 Shioe, Amagasaki-shi, Hyogo Nisshin Corporation F term (reference) 4F100 AG00C AK17B AK18A AK18A BA03 BA07 BA10A BA10C BA13 DG12C EC032 EJ192 EJ452 GB41 GB66 JB01 JB16B JG00 JJ03 JK15 JL13 YY00A YY00B YY00C

Claims (5)

[Claims] 1. A sheet substrate made of a polytetrafluoroethylene resin, a film made of a fluorine-based resin having a melt fluidity, and a glass cloth are continuously fed out from respective winding rolls so that the film becomes an intermediate material. A high-temperature roll having a roll surface temperature higher than the melting point of the fluororesin of the film and a roll surface temperature lower than the melting point of the high-temperature roll while continuously running the superposed sheet. By passing between the low-temperature roll that constitutes the nip part and heat-pressing,
A method for producing a chemical-resistant sheet, characterized in that the sheet base material and the glass cloth are a laminated sheet in which the glass substrate is integrated via a molten resin layer of the film. 2. The method for producing a chemically resistant sheet according to claim 1, wherein the superposed sheet is passed between the high-temperature roll and the low-temperature roll so that the surface on the glass cloth side is in contact with the high-temperature roll. 3. A film base made of a polytetrafluoroethylene resin, a film made of a fluorine-based resin having melt fluidity, and a glass cloth are continuously fed out from each of the winding rolls, so that the film becomes an intermediate. While the rolled sheet is continuously running, the roll surface temperature is passed between a pair of high-temperature rolls higher than the melting point of the fluorine-based resin of the film, and heat-pressed. A laminated sheet in which the sheet substrate and the glass cloth are integrated via the molten resin layer of the film by bringing at least the surface of the sheet substrate side into contact with the peripheral surface of a low-temperature roll whose roll surface temperature is lower than the same melting point. A method for producing a chemical-resistant sheet. 4. The roll surface temperature of the high-temperature roll is set at least 50 ° C. higher than the melting point of the fluororesin of the film, and the roll surface temperature of the low-temperature roll is set at least 50 ° C. lower than the same melting point. 4. The method for producing a chemical-resistant sheet according to any one of claims 1 to 3. 5. The sheet according to claim 1, wherein the thickness of the sheet substrate is 0.2 to 5 mm, the thickness of the film is 0.05 to 0.2 mm, and the thickness of the glass cloth is 0.2 to 2 mm. A method for producing the chemical-resistant sheet as described above.