JPH115279A - Synthetic resin laminated body, and its welding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated plate which is a resin plate having a strong ozone-resistance and a strong organic solvent-resistance, and in addition, has a high rigidity, and by which a sterilizing treatment tank can be manufactured even when the plate thickness is thin. SOLUTION: A rigid vinyl chloride resin layer 1 of 3-20 mm and a fluororesin layer 3 of 0.1-2.0 mm are laminated and integrated. The rigidity is kept by the rigid vinyl chrolide resin layer 1, and an ozone-resistance, etc., are displayed by the fluororesin layer 3, and with this laminated plate only, a sterilizing treatment tank, etc., can be manufactured. Also, the fluororesin layers 3 can be welded to each other, and the total area of the internal surfaces of the tank is covered with the layer 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin laminate which can be used in a sterilization tank, a disinfection tank, a semiconductor device, and a water and sewage treatment apparatus, and a method for welding the same.

[0002]

2. Description of the Related Art Heretofore, the above-mentioned sterilization tank and the like have been formed by welding a difluorinated ethylene resin plate and forming the tank by welding.

[0003] On the other hand, a laminated plate in which a fluororesin layer of several μm is formed on the surface of a synthetic resin to improve the stain resistance, abrasion resistance, weather resistance and the like is known. For example, Japanese Utility Model 60-2453
No. 8 discloses a laminate in which an acrylic resin layer and a fluororesin layer are sequentially laminated on the surface of a polycarbonate resin.

[0004]

However, in order to manufacture a tank using a difluoroethylene resin plate, considerable skill is required, and the resin plate warps at the time of welding so that the rectangular tank cannot be formed. Due to the lack of rigidity, a thick resin plate had to be used, resulting in an expensive tank.

On the other hand, the thickness of the fluororesin layer used in the laminated plate is extremely thin, 1 to 10 μm, and it can sufficiently exhibit the performance such as weather resistance for architectural applications using the laminated plate as it is. However, if it is to be used for the above-mentioned sterilization tank for industrial use, a welding step is required, and the fluororesin layer around the welded portion is not melted at the time of the welding, or the fluororesin is applied to the welded portion. There was a problem that a portion without a fluororesin layer was formed in the tank because a weld layer could not be formed. Further, there is a problem that the fluororesin layer is damaged during transportation and processing, and the resin inside is exposed, so that the effect of the fluororesin cannot be expected.

SUMMARY OF THE INVENTION The present invention has been made in view of these problems. It is an object of the present invention to provide a fluororesin which has a sufficient rigidity to form a tank even if it is thin and which can sufficiently withstand welding. It is to provide a laminate having layers and a method for welding the laminates together.

[0007]

To achieve the above object, a synthetic resin laminate according to claim 1 of the present invention is a laminate comprising a hard vinyl chloride resin layer and a fluororesin layer. The resin layer has a thickness of 0.1 to 2.0 mm. The thickness of the fluororesin layer is preferably 0.4 to 1.5 mm, and the fluororesin layer is preferably made of ethylene difluoride resin. Is preferably 3 to 20 mm.

[0008] With the laminate having the above structure, sufficient mechanical strength, particularly rigidity, can be imparted by the hard vinyl chloride resin layer, and a tank can be manufactured using a thin laminate. Further, even if hot air is applied to the fluororesin layer during welding, the fluororesin layer has a thickness sufficient to prevent the fluororesin layer from being melted. Can be welded sufficiently.

According to a fourth aspect of the present invention, there is provided a method for welding a laminate.
5. The method for welding synthetic resin laminates according to claim 1 to 4, wherein the hard vinyl chloride resin layers are welded using a vinyl chloride resin welding rod, and the fluorine resin layers are used a fluorine resin welding rod. It is characterized by welding.

According to the above welding method, the surface layer of the welded portion is covered with the fluororesin welded portion, so that the internal vinyl chloride resin welded portion is not exposed.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of a laminate of the present invention, FIG. 2 is a sectional view showing a state where the laminates are joined by welding, and FIG. 3 is a sectional view showing another welding state.

In FIG. 1, reference numeral 1 denotes a hard vinyl chloride resin layer, which is formed by sequentially laminating acrylic resin layers 2, 2 and fluororesin layers 3, 3 on the upper and lower sides thereof, thereby forming a synthetic resin. A laminate A is formed. In the drawings, the fluororesin layer is provided on both the front and back surfaces, but it is needless to say that the laminate may be provided with the resin layer on only one surface.

The hard vinyl chloride resin layer 1 is formed by adding and mixing a lead-based or tin-based stabilizer, a lubricant, a processing aid, and the like to a vinyl chloride resin, and extruding, calendering, or the like. The thickness is 3 to 20 mm. If the thickness is less than 3 mm, the rigidity of the laminate A required when the tank is manufactured cannot be expected, and the thickness is 20 mm.
If the thickness is larger, no more rigidity is required for the tank, but the thickness becomes unnecessary and the cost increases. The mechanical strength of the vinyl chloride resin layer 1 is, for example, the bending strength (A
STM D790) is 90-100 N / mm ² , and the flexural modulus (ASTMD790) is 2500-3800 N / m
m ² , Izod impact strength (JISK6745) is 3 ~
10KJ / m ² , deflection temperature under load (JIS K674
5, 181.3 N / cm ² ) of 65 to 80 ° C. can be preferably used.

Further, by using a post-chlorinated vinyl chloride resin in place of the vinyl chloride resin, the deflection temperature under load can be reduced to 90 to 90.
The temperature can be raised to 100 ° C., and is preferably adopted for a laminated body of a tank used at a severe high temperature.

As the acrylic resin layer 2, rubber-modified acrylic resin is used, and is used for bonding and bonding the fluorine resin layer 3 having poor adhesiveness to the vinyl chloride resin layer 1. The thickness is not particularly limited, but is usually 20 μm.
As described above, those having a thickness of preferably 50 to 500 μm are preferable from the viewpoint of adhesiveness.

The surface layer of the fluororesin layer 3 gives the laminate A properties such as resistance to ozone, resistance to mixed acidity and resistance to organic solvents, which cannot be obtained with the vinyl chloride resin layer 1. It is preferably from 0.1 to 2.0 mm, more preferably from 0.4 to 1.5 mm. 0.1 mm or less,
It will not melt at the time of welding to be described later, the fluororesin layer 3 of the laminate A will not be completely joined to the fluororesin weld layer 31 of the welded portion, or the fluororesin layer of the surface layer will be transported or processed during the lamination A. When the vinyl chloride resin layer 1 is exposed due to scratches on the surface 3, inconvenience is likely to occur. 0.4 thickness
When the thickness is equal to or more than mm, the fluororesin layers are easily joined to each other by a fluororesin weld at the time of welding, which can be said to be a preferable thickness. On the other hand, if the thickness is 2.0 mm or more, the performance is not improved so much and the cost is increased. Therefore, the thickness should be kept at about this thickness. A more preferable thickness is 1.5 mm, which is sufficient to satisfy the above-mentioned ozone resistance and the like.

As the fluororesin, a monofluoroethylene resin, a difluoroethylene resin, a trifluoroethylene resin, or a tetrafluoroethylene resin is used. Among them, the welding work is easy, and the bending work is also possible. A possible difluoroethylene resin is most preferably used.

The laminate A having the above structure may be formed by simultaneously laminating an acrylic resin film and a fluororesin sheet when extruding a vinyl chloride resin, or by laminating a vinyl chloride resin sheet, an acrylic resin film and a fluororesin sheet. May be formed in advance, and these may be hot-pressed to be laminated and integrated, or a sheet in which a fluorine resin and an acrylic resin are laminated may be molded, and a vinyl chloride resin may be extruded or laminated by hot pressing. Alternatively, it can be manufactured by a method such as laminating three layers simultaneously with extrusion by coextrusion.

Since the laminate A thus obtained has the surface layer of the fluororesin layer 3, it is not attacked by ozone and can be sterilized by using ozone.
Used to manufacture sterilization tanks and washing tanks for waterworks, etc.
Alternatively, it is used to line the inner surface of a tank made of concrete or the like. The tank and lining tank obtained in this way do not deteriorate due to the attack of the laminate,
Can be used for a long time. Further, even if it is used to manufacture a tank for containing a mixed acid used in the production of semiconductors and the like, the metal can be used for a long period of time because there is no metal elution and there is no attack by the mixed acid.

Since the mechanical strength such as the rigidity of the laminate A is held by the vinyl chloride resin layer 1, the mechanical strength enough to withstand use even when the laminate A alone is used is supported.
The rigidity is higher than that of the difluoroethylene resin, and the tank can be manufactured with a correspondingly reduced thickness. Furthermore, since the surface fluororesin layer 3 has a thickness of 0.1 to 2.0 mm, when the laminate A is transported or handled during processing,
Even if the fluororesin layer 3 is damaged by hitting an object on the laminate A, it does not penetrate the resin layer 3 and the surface layer is always covered with the fluororesin layer 3.

When a tank is manufactured or lined using these, it is sometimes necessary to join the laminates A by welding. In this welding, as shown in FIG. 2, the vinyl chloride resin layer 1 and the fluororesin layer 3 of the laminate A were formed using a vinyl chloride resin welding rod and a fluororesin welding rod, respectively. And weld.

This welding is most preferably performed so that the polyvinyl chloride resin welding portion 11 maintains the welding strength. This is because even when the fluororesin welded portion 31 is formed, the welded portion 31 itself has no mechanical strength. Especially,
When the thickness of the fluororesin layer 3 is as thin as 0.1 to 0.4 mm,
It is because it is difficult to weld them and it is not possible to obtain welding strength. However, when the thickness of the fluororesin layer 3 exceeds 0.4 mm, the resin layers 3 can be welded to each other, and the strength of the welded portion 31 can be increased, which is preferable. In addition, the thickness of the fluororesin layer is 0.1 to 0.4 mm.
When welding is difficult, a fluororesin film of 0.4 mm or less is placed on the polyvinyl chloride resin welding portion 11 and
The fluororesin layers may be joined by applying hot air of about 0 ° C. and melting.

As shown in FIG. 3, when the acrylic layer portion 21 is provided between the vinyl chloride resin welding portion 11 and the fluororesin welding portion 31 by welding or a film, the vinyl chloride resin welding portion 11 and the fluororesin Acrylic layer part 2 with welded part 31
1, it is possible to prevent the fluororesin welded portion 31 from being peeled off by being integrated more firmly, and to improve the welding strength.

Further, since hot air of about 250 ° C. is used when welding the vinyl chloride resin layer 1, the hot air hits the fluororesin layer 3 having a melting temperature of 130 to 180 ° C. around the welded portion, but the thickness is 0.1 mm. As described above, the welding of the vinyl chloride resin layer 1 ends before the resin is melted and blown away by hot air, and the fluororesin layer 3 does not disappear.

Example 1 2.5 parts by weight of a lead-based stabilizer, 1.0 part by weight of a lubricant, and 5.0 parts by weight of an acrylic processing aid were added to a vinyl chloride resin, followed by mixing and kneading. A 5 mm thick calender sheet was prepared. This calendar sheet 1
A rubber modified acrylic film of 100 μm and a 1 mm difluoroethylene resin sheet are superimposed on both upper and lower surfaces of six sheets,
Hot pressing at 185 ° C., a 1.0 mm thick laminate of the present invention in which a 1.0 mm difluoroethylene resin layer is laminated and integrated on the front and back of an 8 mm vinyl chloride resin layer via an arylyl layer A body (Example 1) was obtained.

Example 2 Instead of the above-mentioned vinyl chloride resin, a chlorinated vinyl chloride resin was used.
1.5 parts by weight of a lubricant and 5.0 parts by weight of an acrylic processing aid were added, and a 0.5 mm-thick calender sheet was prepared in the same manner. 16 calender sheets and 100 μm
Hot-pressed at 195 ° C. using a rubber-modified acrylic film and a 1 mm difluoroethylene resin sheet to form 1.0 m
Thus, a laminate (Example 2) of the present invention having a thickness of 10.0 mm, in which m difluoroethylene resin layers were laminated and integrated via an arylyl layer, was obtained.

[Comparative Example 1] Twenty calender sheets prepared in Example 1 were superimposed and hot pressed similarly to obtain a 10.0 mm thick vinyl chloride resin plate (Comparative Product 1).

[Comparative Example 2] Twenty calender sheets prepared in Example 2 were overlaid and hot pressed similarly to obtain a chlorinated vinyl chloride resin plate having a thickness of 10.0 mm (Comparative Product 2).

Comparative Example 3 A laminated film in which 45 μm acrylic resin and 5 μm difluoroethylene resin were laminated on both upper and lower surfaces of the 20 calendar sheets prepared in Example 1 was used. A 10 mm thick laminate (comparative product) in which a 5 μm-thick ethylene difluoride resin layer is laminated and integrated via an acrylic layer on the front and back of a vinyl chloride resin layer 3) was obtained.

[Comparative Example 4] The calender sheet prepared in Example 2 and the laminated film used in Comparative Example 3 were laminated by hot pressing in the same manner as in Comparative Example 3 to obtain a chlorinated vinyl chloride resin. A 10 mm-thick laminate (comparative product 4) was obtained by laminating and integrating a 5 μm-thick ethylene difluoride resin layer on the front and back of the layer via an acrylic layer.

Comparative Example 5 As a difluorinated ethylene resin plate, "PVDF plate" manufactured by Takiron Co., Ltd. was used.
A 0 mm resin plate (Comparative product 5) was used.

The mechanical strength of the above-mentioned Examples 1 and 2 and Comparative Examples 1 to 5 was measured according to JIS 6745 and ASTM 790.
It tested based on. Table 1 shows the results.

[Table 1]

From Table 1, it can be seen that Examples 1 and 2 are slightly inferior in mechanical strength to Comparative Examples 1, 2, 3, and 4 because of lamination of a 1 mm thick difluoroethylene resin. It has considerably better strength than Example 5, and in particular, greatly exceeds the flexural modulus. It can be seen that the tank can be used satisfactorily even if the tank is manufactured using a considerably thin plate of the embodiment. In addition, the other strengths of Examples 1 and 2 are almost the same as those of Comparative Examples 1 to 4, indicating that they can be used similarly to the vinyl chloride resin plate. Furthermore, it can be seen that the product 2 has a higher withstand load deflection temperature as high as 20 ° C. than the product 1 and can be used in applications where the working temperature is high.

Each of the above-mentioned actual products and each of the comparative products were butt-welded, and a tensile test after welding was performed. In Example 1, the vinyl chloride resin layers were welded to each other using a 3 mm polyvinyl chloride resin welding rod with hot air at about 200 ° C., and the difluoroethylene resin layers were bonded to each other using a 3 mm difluoroethylene resin welding rod. And welded with hot air of about 230 ° C. Example 2 uses a chlorinated vinyl chloride resin welding rod,
The welding was performed in the same manner as in Example 1, except that hot air at 230 ° C. was used.

In the comparative product 3, the vinyl chloride resin layers were welded to each other at about 200 ° C. using a 3 mm vinyl chloride resin welding rod. Since the resin was exposed, welding between the difluoroethylene resin layers could not be performed. Comparative product 4 was welded using a chlorinated vinyl chloride resin welding rod. However, since the surrounding difluoroethylene resin layer was scattered by hot air, this layer was not welded.

Comparative products 2, 3, and 5 were welded using a vinyl chloride resin welding rod, a chlorinated vinyl chloride resin welding rod, and a difluoroethylene resin welding rod, respectively. The tensile strength (welding strength) after welding in this way and the appearance around the welded part were visually observed. Table 2 shows the results.

Further, the products 1 and 2 and the comparative products 1 to 5
Was subjected to a load stress of 30 N / mm ² and left standing in a gas phase having an ozone concentration of 7000 ppm for 30 days to visually observe the appearance. The results are shown in Table 2.

[Table 2]

From Table 2, it can be seen that the welding strength of the products 1 and 2 of the product of the present invention is inferior to those of the comparison products 1 and 2, but the welding strength of the base material is 73.
%, Which indicates that welding is possible without any special skills. The actual products 1 and 2 are comparative products 3 and 4
It is more excellent in welding efficiency, and it is considered that the notch was not generated around the welded portion of the embodiment product, but the notch was generated in the comparative product due to the scattering of the ethylene difluoride resin layer.

Further, the appearance around the welded part is shown in Example 1,
No. 2 shows no abnormality in the surface difluoroethylene resin layer, but Comparative Examples 3 and 4 where the difluoroethylene resin layer was thin.
Shows that the polyvinyl chloride resin is exposed by scattering of the ethylene difluoride resin around the welded portion. If the fluororesin layer is too thin, the layer disappears around the welded portion and the function is partially interrupted. . In addition, it turned out that Examples 1 and 2 maintain the flat plate shape even after welding, and do not warp and warp by welding. Comparative product 5 was slightly warped by welding.

Further, even in the ozone gas phase subjected to a stress load, it was found that Examples 1 and 2 had no abnormality and had good ozone resistance, but Comparative Examples 1 and 2 and vinyl chloride were exposed. It can be seen that the comparative products 3 and 4 have cracks and cannot be used for applications in which they are exposed to ozone.

[0042]

The invention according to claim 1 is a laminate in which a hard vinyl chloride resin layer and a fluororesin layer having a thickness of 0.1 to 2.0 mm are laminated and integrated, so that mechanical strength, particularly rigidity, is reduced. It has the advantage that a laminate having a smaller thickness than a conventional difluoroethylene resin plate can be used even when used alone. In addition, sufficient welding strength can be ensured by welding, and the laminated body does not warp and warp, so that a tank or the like can be manufactured without requiring skill in welding. Further, the surface fluororesin layer does not disappear even by the hot air at the time of welding, and the tank or lining layer made of the laminated body of the present invention has ozone resistance, mixed acid resistance and the like, and these are used. It has sufficient durability even when used in a sterilization tank, semiconductor device, or the like.

According to a fifth aspect of the present invention, the vinyl chloride resin layer of the laminate is welded to each other, and the fluororesin layer has a thickness of 0.1 to 2.0 mm. Therefore, a fluorine resin welded portion is formed on the surface layer, and the inside vinyl chloride resin layer is not exposed, so that the ozone resistance and the mixed acid resistance can be maintained even when welding is performed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a laminate of the present invention.

FIG. 2 is a cross-sectional view showing a state where the laminates of the present invention are welded.

FIG. 3 is a sectional view showing another welding state of the present invention.

[Description of sign]

 1 vinyl chloride resin layer 2 acrylic resin layer 3 fluorine resin layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29L 9:00

Claims (5)

[Claims] 1. A laminate comprising a hard vinyl chloride resin layer and a fluororesin layer, wherein the fluororesin layer is 0.1 to
A synthetic resin laminate having a thickness of 2.0 mm. 2. The method according to claim 1, wherein the fluororesin layer has a thickness of 0.4 to 1.5 mm.
The synthetic resin laminate according to claim 1, having a thickness of: 3. The synthetic resin laminate according to claim 1, wherein the fluororesin layer is a difluoroethylene resin layer. 4. The synthetic resin laminate according to claim 1, wherein the hard vinyl chloride resin layer has a thickness of 3 to 20 mm. 5. The method for welding synthetic resin laminates according to claim 1 to 4, wherein the hard vinyl chloride resin layers are welded with a vinyl chloride resin welding rod, and the fluororesin layers are fluorine. A method for welding a synthetic resin laminate, wherein the welding is performed using a resin welding rod.