JPH0362149B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to a method for manufacturing a laminated sheet. More specifically, the present invention provides a method for cleaning at least one portion of a fibrous base fabric without pre-wetting the fibrous base fabric and thus without creating wastewater pollution.
The present invention relates to a method for manufacturing a laminated sheet having a polymer coating firmly bound to the surface thereof, so that the polymer coating will not peel off due to strong clattering or vibration. Conventional technology Laminated sheets obtained by forming a polymer film on one or both sides of a fibrous base fabric, such as impermeable waterproof sheets, have been widely used in applications such as truck canopies and sheets for covering piled goods. It is being Conventionally, spun yarn fabrics have been widely used as base fabrics for the above laminated sheets. Such fabrics include vinylon, polyamide, polypropylene,
and those made from spun yarn such as polyester short fibers are common. Such a spun yarn fabric has countless fluffs on its surface, and when a polymer coating is formed on the surface of this fabric, the fluffs on the fabric exert an anchoring effect, causing the interaction between the fabric surface and the polymer coating. This had the advantage that the bond between them was extremely strong. However, spun yarn fabrics cannot be said to fully utilize the inherent strength of their fibers, and therefore, when a laminated sheet requires extremely high mechanical strength, it is necessary to use the yarn used for the base fabric. The strips were thick, and the fabric's basis weight and thickness had to be increased.
This has the disadvantage that the resulting laminated sheet is thick, heavy, difficult to handle, and expensive. In order to eliminate the drawbacks resulting from the use of spun yarn fabrics as mentioned above, fabrics made of filament yarns that are highly efficient in utilizing fiber strength have come to be used. However, filament yarn fabrics have the disadvantage that they do not have fuzz, and therefore their adhesive strength with the polymer coating is lower than that of spun yarn fabrics. Due to this drawback, conventional laminated sheets using filament yarn fabric as a base fabric cannot be used in applications where the sheets are subject to flapping or vibration due to strong wind pressure, such as truck hoods. In order to solve the problems of the laminated sheet using the filament yarn base fabric as described above, gaps are provided between the filament yarns in the fabric structure, and a polymer coating is formed on both sides of such a coarse fabric. Attempts were made to allow both coatings to adhere directly through the gaps in the fabric. Although this method was certainly effective in preventing peeling of the polymer coating, it had the disadvantage that its strength was low because the base fabric was coarse. Therefore, in order to solve the above-mentioned problems of laminated sheets using filament yarn base fabrics, it is necessary to apply a strong adhesive, such as an isocyanate-based adhesive, between the base fabric and the polymer coating, or to apply a polymer coating. Attempts have been made to include an adhesive in the forming material or in the filament within the base fabric. However, fully satisfactory results have not yet been obtained. In addition, in order to stably obtain a bridging-free laminated sheet of a polymer coating using a fibrous base fabric with a relatively dense structure, it is necessary to improve the adhesion between the base fabric and the coating. , and this adhesiveness is required to be uniform for each part of the base fabric.
For this purpose, in the past, desizing, scouring, and
And/or it was considered essential to perform a lubricating treatment such as staining, if desired, and to clean the surface. This is because glue, wax, oil (spinning oil, spinning oil), etc. are attached to the base fabric greige, and these reduce the adhesion to the polymer coating and make it uneven. However, pre-lubrication treatments such as desizing and scouring inevitably require treatment to make the wastewater pollution-free.
If these wastewaters are discharged without treatment, there is a problem in that they cause a significant increase in BOD in the environmental water system, causing so-called wastewater pollution. This wastewater pollution-free treatment naturally has the problem of increasing the cost of treating the base fabric. Problems to be Solved by the Invention The present invention has high strength and excellent adhesion strength between the polymer coating and the base fabric, and even when subjected to vibration or slapping under severe conditions, they do not peel off. It is possible to produce a laminated sheet with stable quality without causing any waste water pollution. A method for manufacturing a laminated sheet is provided. Means for Solving the Problems and Their Effects The method for manufacturing a laminated sheet of the present invention involves applying a corona discharge treatment to at least one side of a fibrous base fabric that is still a gray fabric, and applying a corona discharge treatment to the surface of the base fabric that has been subjected to the corona discharge treatment. , which is characterized by forming a polymer film. Fibrous base fabrics useful in the present invention include natural organic fibers,
For example, inorganic fibers such as cotton and hemp; recycled fibers such as glass fibers, carbon fibers, asbestos fibers, and metal fibers; viscose laces;
Semi-synthetic fibers, such as di- and tri-acetate fibers, such as Kyupra, and synthetic fibers, such as nylon 6, nylon 66, polyester (polyethylene terephthalate, etc.) fibers, aromatic polyamide fibers, acrylic fibers, polyvinyl chloride fibers. , polyolefin fibers, and polyvinyl alcohol fibers made insoluble or hardly soluble in water. The fibers in the base fabric may be in any form such as short fiber spun yarn, filament (long fiber) yarn, split yarn, or tape yarn, and the base fabric may be woven, knitted, nonwoven, or a composite fabric thereof. It may be. Generally, the fibers used in the laminated sheet according to the present invention are preferably vinylon fibers, polyamide fibers (including aliphatic and aromatic polyamide fibers), polyester fibers, and glass fibers, which have little elongation under stress. Considering this, it is preferable that the fiber is in the form of a long fiber (filament).
In addition, it is preferable that a plain woven fabric is formed. However, the textile structure and its form are not particularly limited. As the fibrous base fabric, a base fabric made of filament yarn is preferable, and the laminated sheet obtained using this filament yarn base fabric has a high level of mechanical strength and is useful for industrial materials. be. Filament yarn fabrics useful in the method of the invention include:
In the case of synthetic fibers, those consisting of filament yarns with a single fiber strength of 30 deniers or less are preferred in order to obtain good adhesive strength, and the weave of the filaments is 0.05.
It is more preferably in the range of ~30 deniers, and even more preferably in the range of 1 to 15 deniers. Further, when a glass fiber yarn fabric is used, it is preferable that the single fiber diameter is within the range of 1 to 10 microns in order to obtain good adhesive strength. Generally, the base fabric has a basis weight of 50 to 1000 g/ ^m2 , preferably 100 to 800 g/ ^m2 , or 30Kg/3
It is preferable to use a fabric having a tensile strength of 60 to 600 Kg/3 cm, for example, 60 to 600 Kg/3 cm. The raw fibrous base fabric used in the method of the present invention may be subjected to a process in a dry state, such as heat setting, if necessary, before the corona discharge treatment, but may also be subjected to desizing, scouring, etc. There is no need for wet pretreatment steps such as dyeing. Here, greige fibrous base fabric is one that is directly supplied from the weaving, knitting, nonwoven manufacturing, or composite fabric manufacturing process, and has not undergone any wet processes such as desizing, scouring, bleaching, or dyeing. Therefore, the surface of the fiber or thread is coated with a sizing agent,
Wax and/or various oils are attached. In the method of the present invention, one side of the greige base fabric,
Alternatively, both surfaces are subjected to corona discharge treatment. In corona discharge treatment, a high voltage is applied between a roller that supports the base fabric and an electrode placed opposite it to generate a corona discharge, during which time the base fabric is moved and the surface of the base fabric is sequentially treated. It is something. In the method of the present invention, the corona discharge treatment can be carried out continuously while the base fabric is run at a predetermined speed between a pair of rolled discharge electrodes as shown in FIG. 1, for example. In Figure 1, 1
The pair of rolled discharge electrodes 1 and 2 each have one metal electrode core 3, 4 and a non-electrically conductive resin layer 5, 6 (for example, a rubber layer) covering it. The electrode core 3 of one roll-shaped discharge electrode is connected to a high-voltage power source 7, and the electrode core 4 of the other roll-shaped electrode is connected to ground 8. The base fabric 10 fed through the guide roll 9 has its back side 11
is moved between the discharge electrodes at a constant speed (for example, 2 to 10 m/min) so as to be in contact with the circumferential surface of the rolled electrode 2 connected to the ground. At this time, when a predetermined electrode (100 to 200 V) is applied between both rolled electrodes 1 and 2, a corona discharge of 10 to 60 A is generated, and the surface 12 of the base fabric 10 is treated by this corona discharge. The distance A between the circumferential surfaces of both electrodes is 30 mm or less, generally 5 ~
It is 20mm. The base fabric 10 subjected to the corona discharge treatment is passed through a guide roll 13 and wound up to form a roll 14. For corona discharge treatment, spark gap method,
Vacuum tube method, solid state method, etc. can be used. In order to improve the adhesion of the base fabric, it is preferable to have a critical surface tension of 35 to 60 dyn/cm.
~50000W/ ^m2 /min, preferably 150~40000W/
It is preferable to apply processing energy of about m ² /min. The amount of energy to be applied (voltage, current amount, distance between electrodes, etc.) is determined in consideration of the width of the base fabric, processing speed, etc. For example, when performing corona discharge treatment on a base fabric surface with a width of 2 m at a processing speed of 10 m/min, the output (power consumption) is 4 kW ~
Preferably, it is about 800kW. However, it is not necessarily limited to this condition. The corona discharge device used in the method of the invention may be of the usual metal electrode type. By performing corona discharge treatment in this way, the glue and oil on the surface are decomposed, removed, or activated.
In the process of forming the polymer coating, there is no adverse effect on the adhesive force between the base fabric and the coating. Such an effect of corona discharge treatment was discovered for the first time in the present invention. The corona discharge treated substrate is then coated with a high molecular weight polymer coating on one or both surfaces thereof. As the high molecular polymer, synthetic resin, synthetic rubber, or natural rubber is used. Preferred synthetic resins include, for example, polyvinyl chloride (PVC), polyurethane, ethylene-vinyl acetate copolymer, polypropylene, polyethylene, and polyacrylonitrile. , polyester, polyamide,
Fluorine resins, silicone resins, and other known materials can be used. Examples of preferable synthetic rubbers include styrene-butadiene rubber (SBR), chlorosulfonated polyethylene rubber,
Examples include polyurethane rubber, butyl rubber, isoprene rubber, silicone rubber, fluorine rubber, and other known materials. In particular, polyvinyl chloride, fluorine-based and silicone-based rubbers and resins, and acrylic resins are preferred polymers for the present invention. These polymers may contain plasticizers, colorants, various stabilizers, flame retardants, etc., as long as they do not impede the purpose of the present invention. In particular, in order to make the adhesiveness between the fibrous base fabric and the polymer stronger, an adhesive substance may be interposed at the interface between the fibrous base fabric and the polymer. Examples of useful adhesive substances include melamine adhesives, phenolic adhesives, epoxy adhesives, polyester adhesives, polyethyleneimine adhesives, polyisocyanate adhesives, polyurethane adhesives,
Examples include, but are not limited to, acrylic adhesives, polyamide adhesives, and copolymer adhesives such as vinyl acetate-vinyl chloride adhesives and vinyl acetate-ethylene adhesives, but are not limited to these. Any adhesive can be used. The adhesive substance is
It may be used by being mixed into the polymer, or it may be applied to the interface. The surface coating can be formed by conventional methods such as
This can be carried out by a calendering method, an extrusion method, a coating method, a dipping method, or the like. The polymer coating preferably has a weight of at least 30 g/m ² , for example from 100 to 1200 g/m ² . The present invention will be further explained below with reference to Examples. Example 1, Comparative Example 1 and Reference Example 1 Example 1 was carried out as follows. Supply base fabric A Polyester multifilament fiber base fabric with the following composition 1000d/200f x 1000d/200f/32 pieces/25.4mm x 32 pieces/25
A raw fiber base fabric of .4mm plain weave, fabric weight 300g/ ^m2 , thickness 0.35mm was used without desizing or scouring. Corona discharge treatment was applied to both sides of the raw base fabric using the apparatus shown in FIG. The base fabric was fed between a pair of discharge electrodes at a speed of 10 m/min so that one layer of the base fabric was in contact with the circumferential surface of the rolled electrode connected to ground. On the back side of this base fabric, the distance A between both electrodes is 10 mm, and the voltage is 160.
Volts, current 18 amps maximum output 8kW (power consumption
Corona discharge treatment was performed continuously at a rate of 7.9kW/hr). At this time, the diameter of the metal electrode core of both electrodes is 20
cm, the thickness of the resin layer is 2 mm (roll diameter 20.4 cm),
The roll length was 2 m and the discharge width was 1.92 m. At this time, the energy radiated to the sample surface was approximately 440W/
m ² /min. On both sides of the corona discharge treated fibrous base fabric,
100 parts of Nituporan 3105 and 15 parts of Coronate L
(Both are products of Nippon Polyurethane Industries Co., Ltd.: polyurethane adhesive) diluted with ethyl acetate to make a 50% solution, which was applied in an amount of 30 g/m ² and dried. Next, a PVC film (0.1 mm) having the composition shown below was attached to both sides by heating. PVC 100 parts DOP (plasticizer) 75 parts Titanium dioxide 8 parts Antimony trioxide (flame retardant) 5 parts Zinc stearate (stabilizer) 3 parts In Comparative Example 1, the same operation as in Example 1 was performed. However, the corona discharge treatment was omitted. In Reference Example 1, the same operations as in Example 1 were performed. However, the base fabric was subjected to de-sizing and scouring using a conventional method. Table 1 shows the performance of each of the obtained laminated sheets.

[Table] As Table 1 clearly shows, the performance of the laminated sheet obtained by the method of the present invention is completely superior to that of Reference Example 1, which was subjected to desizing and scouring, both in terms of performance values and uniformity. It's comparable. Moreover, when Example 1 and Comparative Example 1 are compared, the excellent effects of the corona discharge treatment are clear. In Example 1, the desizing and scouring steps are omitted, so no dirt or bad odor is generated at the process site, and since there is no wastewater, there is no wastewater pollution at all, and there is no need for wastewater treatment. Therefore, the economic effect of the method of the present invention is extremely high. Example 2 The same operation as in Example 1 was performed. However, as the base fabric, a spun yarn fabric having the following structure, weight, and thickness was used in its raw form. 14s/1×14s/1/53 pieces/25.4 mm×50 pieces/25.4 mm Plain weave weight: 210 g/m ² Thickness: 0.3 mm Polymer coatings were formed on both sides of the base fabric as described below. Treatment liquid composition PVC 100 parts DOP 60 parts CaCO ₃ 20 parts Cd-Ba stabilizer 3 parts Toluene 100 parts Nitsuporan 3105 10 parts Coronate L 2 parts Soak the base fabric in the above treatment liquid, squeeze it with a mangle,
The PVC resin was gelled and fixed by heat treatment at 190°C for 3 minutes. The amount of the waterproof layer thus applied was 200 g/m ² in terms of solid content. The obtained laminated sheet showed water pressure resistance of more than 2500 mm of water column, and also showed excellent water pressure resistance even after being rubbed by hand 100 times. Example 3 The same operation as in Example 1 was performed. However, as the base fabric, the following glass fiber base fabric was used as it was. DE150 1/2 3.3s/55 pieces/25.4mm×51 pieces/25.4mm
Example 1 was applied to both sides of the Turkish satin textured 290 g/m ² corona discharge treated base fabric.
The same PVA film as described in Example 1
It was attached in the same way. The resulting laminated sheet had a water pressure resistance of 2500 mm water column or more, and a peel strength of about 10 kg/3 cm. Effects of the Invention The method for manufacturing a laminated sheet according to the present invention includes desizing and
The adhesive strength between the fibrous base fabric and the polymer coating can be significantly increased simply by corona discharge treatment without the need for wet pre-treatments such as scouring or bleaching. Therefore, there are no problems associated with wet pretreatment steps, such as problems with odor, wastewater treatment, and wastewater pollution. In addition, the method of the present invention makes it possible to firmly bond the polymer coating to the filament yarn fabric, which has conventionally been thought to have low adhesiveness, even if it is used as a base fabric in its raw form. It has become possible to manufacture laminated sheets that are lightweight and have high mechanical strength. The laminated sheet produced by the method of the present invention does not cause delamination even when used in applications where it is subjected to severe flaps and vibrations caused by wind pressure, and is of extremely high practical value.

[Brief explanation of drawings]

FIG. 1 is a process explanatory diagram of the corona discharge treatment used in the method of the present invention. 1, 2...discharge electrode, 3, 4...electrode core, 5,
6... Resin layer, 7... High voltage power supply, 8... Earth,
9, 13... Guide roll, 10... Base fabric, 11
. . . Surface in contact with the grounded electrode, 12 . . . Treated surface of base fabric, 14 . . . Winding roll, A . . . Electrode spacing.

Claims (1)

[Scope of Claims] 1. A lamination characterized by subjecting at least one side of a raw fibrous base fabric to a corona discharge treatment, and forming a polymer coating on the surface of the base fabric subjected to the corona discharge treatment. Method of manufacturing sheets. 2 The fibrous base fabric is a natural organic fiber, an inorganic fiber,
The method according to claim 1, comprising at least one type of fiber selected from recycled fibers, semi-synthetic fibers and synthetic fibers. 3. The method according to claim 1, wherein the polymer is selected from synthetic resins, synthetic rubbers and natural rubbers. 4. A patent in which the polymer coating is formed from at least one member selected from polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, polyacrylonitrile, polyester, polyamide, fluorine-containing resin, and silicone resin. The method according to claim 1. 5. The polymer coating is formed from at least one member selected from natural rubber, styrene-butadiene rubber, chlorosulfonated polyethylene rubber, polyurethane rubber, butyl rubber, isoprene rubber, silicone rubber, and fluorine-containing rubber. A method according to claim 1. 6. The method of claim 1, wherein the weight of the polymer coating is in the range of 30 to 2000 g/ ^m2 .