JPS6189374A - Production of water-proof sheet - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing a waterproof sheet. More specifically, the present invention relates to a method for manufacturing a waterproof sheet in which the fibrous base fabric constituting the waterproof sheet has no water absorbency.

BACKGROUND OF THE INVENTION Conventionally, waterproof sheets have been manufactured by forming a coating made of a high molecular weight polymer on the surface of a fibrous base fabric. However, in a waterproof sheet formed by forming a coating on both sides of a fibrous base fabric, if the intermediate layer of fibrous base fabric sandwiched between the coatings cracks or tears even slightly, the crack or tear occurs. However, even if such a phenomenon does not occur, there is a drawback that water is absorbed from the cut cross section of the sheet. If the fibers are dense, this water absorption is further increased by capillary action. Then, due to the absorption of water,
The waterproof sheet is not bulky and heavy, and the adhesion between the fibrous base fabric and the coating is reduced. In addition, the absorbed water is released from the fibrous base fabric, and furthermore, there is a drawback that, for example, it absorbs mold, sewage, and water with unusual colors, which spoils the appearance of the sheet.

Problems to be Solved by the Invention In order to eliminate these drawbacks, conventional practice has been to treat a fibrous base fabric with a water repellent and then form a polymer coating on both surfaces thereof. In this case, since the fibrous base fabric is treated with a water repellent, alpha permeation of water is prevented, but on the other hand, if the water repellent effect is increased, the adhesion between the coating and the fibrous base fabric will deteriorate. The adhesion strength of the film decreases, making it undesirable for practical use. Efforts have also been made to improve adhesion by adding adhesive substances such as incyanate to water repellents and coating agents, but no satisfactory results have been achieved. This is the current situation.

In view of these current circumstances, the inventors of the present invention have made extensive studies and have developed a fibrous base fabric with sufficient water repellency.

Moreover, the inventors have discovered a method for achieving sufficiently high adhesion between the fibrous base fabric and the coating, and have arrived at the present invention.

Means for Solving the Problems According to the present invention, there is provided a method for producing a waterproof sheet by forming a polymer coating on both sides of a fibrous base fabric. It is characterized in that it is first treated with a water repellent, then both surfaces thereof are subjected to low temperature plasma treatment, and then a polymer film is formed on both surfaces.

Fibrous base fabrics useful in the present invention include natural fibers such as cotton, linen, inorganic fibers such as glass fiber, carbon fiber,
Asbestos fiber, gold-eye fiber, etc. M raw LRHE, fl
Semi-synthetic fibers such as lt, hiscose rayon, ki, dela, etc., such as no and tri acetate +1 fibers,
and synthetic fibers, such as nylon 6, nylon 66, polyester (polyethylene terephthalate, etc.) fibers, aromatic 18 de') 7 mido fibers, acrylic fibers, polyvinyl chloride fibers, polyolefin fibers, and insolubilized or H-solubilized polyvinyl alcohol fibers. It consists of at least one species transported from . The fibers in the base fabric may be in any form such as short fiber spun yarn, long fiber yarn, nuplit yarn, or tape yarn, and the base fabric may be woven, knitted, nonwoven, or a composite fabric of these. There may be. Generally, f! is used in the waterproof sheet according to the present invention. ! i. The fibers are preferably polyester fibers and glass fibers, and in view of their low elongation under stress, these fibers are preferably in the form of long fibers (filaments), and are preferably in the form of plain woven fabrics. However, there are no particular limitations on the wire structure or its form. The fibrous Iffx base fabric is useful for maintaining the mechanical strength of the resulting tarpaulin sheet at a high level.

These base fabrics are first treated with a water repellent (some of which necessarily exhibit oil repellency) for the purpose of imparting water repellency (water absorption prevention properties). Typical water repellent (oil repellent) agents include, for example, wax, aluminum soap, zirconium salts, quaternary ammonium salts (e.g., stearoylmethylamide methylene pyrizonium salt), N-methylol fatty acid amides (e.g., N-methylol stearic acid amide),
amine resin derivatives (e.g. stearoylmelamine),
Examples include fluorine compounds (for example, 1.pl IJ acrylic acid fluorinated alkyl ester), silicones (for example, trimethylpolysiloxane), and other known water repellents. Are these water repellents used alone or in combination of two or more? It can be used as a single compound. Although the treatment with the water repellent can be carried out by impregnation, coating, spraying, or other methods, the impregnation method is simple and effective.

The base fabric treated with a water repellent in this manner is dried or, as the case may be, without being dried, is subjected to a low-temperature plasma treatment. Low temperature plasma treatment is 0.01 to 10 To
This can be carried out by exposing the fibrous base fabric to low-temperature plasma of a gas that does not have plasma polymerizability under a pressure of . As a plasma generation condition, for example, turtle ()
It is sufficient to apply a ↑+g force of 13.56 kHz and 10 to 500 W in between, and sufficient results can be obtained with either polarized or non-polarized discharge. The plasma processing time was 7t1. Although it varies depending on the pressure, generally a few seconds to several tens of minutes is sufficient.

In addition to the above methods, there are various plasma processing methods available.
1. For example, discharge frequency bands include low frequency, microwave,
Direct current can be used, and the plasma generation mode can be selected from glow discharge, corona discharge, spark discharge, silent discharge, etc. In addition to external electrodes, the electrodes may also be of the internal type (5), coil type, etc., or inductively coupled. However, no matter what method is used, care must be taken to ensure that the surface of the material is not altered by discharge heat. Gases that do not have plasma polymerizability include helium, neon, argon, nitrogen, nitrous oxide, nitrogen dioxide, oxygen,
air, carbon monoxide, carbon dioxide, hydrogen, chlorine, or halides such as hydrogen chloride, bromine cyanide, tin bromide,
There are sulfides such as sulfur, sulfur dioxide gas, and hydrogen sulfide.
These gases can be used alone or in combination.

In the present invention, in a waterproof sheet formed by forming a waterproof coating on both sides of a fibrous base fabric, water absorption of the fibrous base fabric is prevented, and the low-temperature plasma treatment
It is necessary to apply this treatment to both surfaces of the fibrous base fabric treated with a water repellent. In the present invention, it has been found that the low-temperature plasma treatment is performed only on the surface layer of the surface of the base fabric, which greatly improves the adhesion between the fibrous base fabric and the coating, making it preferable.

The base fabric thus treated is then subjected to the formation of a high-molecular-weight polymer coating on both shell surfaces.

Examples of high-molecular polymers include synthetic resins, synthetic rubbers, and natural rubbers. Examples of suitable synthetic resins include polyvinyl chloride (PVC), polyurethane, ethylene-vinyl acetate copolymer, and Aitu Takuchi.

Examples include polypropylene, polyethylene, polyacrylonitrile, polyester, polyamide, fluororesin, silicone resin, and other known materials. Examples of preferable synthetic rubbers include styrene-butadiene comb (SBR), chlornulfonated polyethylene rubber, polyurethane rubber, butyl comb, Inglen rubber, silicone comb, fluorinated rubber, and other known materials. be. 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, fillers, colorants, various stabilizers,
It may also contain flame retardants and the like.

In particular, in order to strengthen the adhesiveness between the fibrous base fabric and the polymer, it is more preferable to interpose an adhesive substance 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 fashionable adhesives, polyisocyanate adhesives,
Examples include polyurethane adhesives, acrylic adhesives, polyamide thread adhesives, and copolymer adhesives such as vinyl acetate-vinyl chloride adhesives and vinyl acetate-ethylene adhesives.
Any known adhesive can be selected and used without being limited to these. The adhesive substance may be used by being mixed into the polymer, or may be applied to the interface.

The surface coating can be formed by a conventional method, such as a calendering method, an extrusion method, a coating method, or a guying method.

Effects of the Invention In the waterproof sheet obtained by the present invention, the fibrous base fabric does not contain any water (no water is absorbed), and the adhesion of the film is extremely good, so it has excellent waterproof performance. It also has excellent durability. Furthermore, in the method of the present invention, stable production of waterproof sheets is possible;
Product performance also becomes stable. Therefore, the present invention provides an industrially extremely advantageous method for producing a waterproof sheet.

Example The present invention will be further explained below with reference to Examples.

Example 1 Polyester fiber base fabric: basis weight 300 g/m2 thickness 0.35 mm was treated with Hobotex FTC (C) as a water repellent under the following conditions.
1ba-Gelgy (amino resin derivative water repellent). Catalyzer RB as a reaction catalyst
(C1ha-Gsfgy product) by Hogetex FT
It was used at a ratio of 25% by weight to C.

Water repellent concentration 9.0.4.5.3.6.3.0,2.1
．． 1.5, (% aqueous solution) 0.9.0.3 Solid content adhesion concentration 3.0.1.5.1.2.1, 0.0.
7, 0.5° (%owf) 0.3, 0.1 After immersing the base fabric in a water repellent bath of each concentration, it was squeezed with a mangle so that the wet adhesion tc was 100 g/m2.
It was pre-dried at 580-90°C, then baked at 150°C for 3 minutes, and treated with a water repellent (conventional treatment).

Furthermore, the sample thus obtained was treated using a low-temperature plasma processing device ffff1 under the following conditions: vacuum degree 2 Torr, acidic gas flow f7fr, ] 00 ml/min, and high frequency output 400 W (frequency 13.56 MIIz). So 2
The sample was subjected to a low temperature plasma treatment for 1 minute (treatment of the present invention).

Each of the fibrous base fabrics obtained in Tonoyo 5.
and on both sides 100 parts of Niraporan 3105 and 1
5 parts of Coronet) L (both produced by Nippon Polyurethane Industries (
Co., Ltd. product: polyurethane adhesive) was diluted with ethyl acetate to make a 50% solution, which was applied in an amount of 3097 m2 and dried. Next, a PvC film (0,
1 fence) was attached by heating.

PVC 100 parts DOP (plasticizer) 75 parts Titanium dioxide
8 parts antimony trioxide (flame retardant) 5 parts zinc stearate (stabilizer) 3 parts The peel strength and water absorption of the resulting waterproof sheets were measured.

Measurement method Peeling strength crab JIS-6328-19775, 3,
Compliant with 7 peel test.

A sample with a length of 20 cm and 173 m was taken from the water-absorbent double-sided cloth, and the upper part was fixed in the length direction.

Immerse the lower end of the dot about 0.5 crn in an immersion solution containing commercially available red ink diluted to 5% in an immersion container, soak it at room temperature for 24 hours, then take it out, and sandwich the immersion solution adhering to the lower end onto a piece of paper. Wipe it gently with water and measure the height of the red ink (the larger the size, the more water absorption).

The results are shown in Table 1. The water pressure resistance was 2000 columns or more in all cases.

The practical guideline for the water absorbency of a catfish is that it must be thrown at least 10 m+++, preferably 5 or less, and preferably O. In general, the practical guideline for peel strength is 6 kli.
l/3 cm or more, preferably 8-9 kg/3 an or more. As can be seen from Table 1, it can be seen that in the conventional method, the sample plate 3 has a performance that is almost at its limit. However, it is difficult to obtain products with stable production and stable performance under these conditions. However, according to the method of the present invention, the peel strength is hardly affected by the concentration of water repellent as in the conventional method, and high adhesive strength can be obtained, and stable products can be obtained under stable processing conditions. You can get a performance tarpaulin.

Example 2 Polyester spun yarn fabric: Weight: 19097m2 Thickness: 0.3mm After being immersed in a 5% aqueous solution of Tex FTC, it was squeezed using a mangle to pick up 100 fl/m2 and pre-dried at 80 to 90°C.

Next, the fabric was baked at 150° C. for 3 minutes to adhere the water repellent to obtain a treated cloth with a water repellent coating of N it 2.5% owf. This treated fabric was subjected to waterproofing treatment under the following conditions, either as it was (conventional method) or treated with low-temperature plasma in the same manner as in Example 1 (invention method).

PVC 100 parts DOP 60 parts Ca COs 20 parts Cd-Ba stabilizer 3 parts Toluene 1000 0 parts Niraporan 310 10 parts Coronat, immersed in 2 parts solution, squeezed with a mangle, heat treated at 190°C for 3 minutes, PVC The resin was dull and stuck. The amount of adhesion of the waterproof layer applied in this way was 20,097 m in solid content.
It was 2. The water pressure resistance of the obtained waterproof fabrics is 200
It was 0+nm water column or more.

When we made a Citruk canopy using this waterproof sheet and put it into practical use, no water seepage into the fibrous base fabric was observed, but when using the conventional method, the film was rubbed off and peeled off after about a month, and the water pressure resistance decreased. However, after two months, it became unusable.

However, no abnormalities were observed in the sheet obtained by the method of the present invention even after two years of use.

Example 3 Glass fiber base fabric: Scotch fabric made of gray fabric with a basis weight of 29097 m2 and a fluorine-based water and oil repellent.
The cloth was immersed in a treatment solution containing 5% C-232 (product of Sumitomo 3M), squeezed with a pick-up mangle to 50%, pre-dried, and then baked at 150°C for 1.5 minutes to obtain a water-repellent-treated cloth. (conventional method).

Furthermore, this was subjected to the following low-temperature plasma treatment.

That is, the base cloth is set in the plasma generation equipment 1, and the pressure is increased to O3Torr while passing argon gas under reduced pressure.
Plasma is generated by applying and releasing 50 W of high-frequency power to
Processed for minutes.

Next, a PVC film was attached to both sides of each base fabric by heating in the same manner as in Example 1 to obtain a waterproof sheet. The water pressure resistance of the obtained sheets was 2000
mm water column or more, and the water absorption was O in all cases. However, the peel strength of the sheet obtained by the method of the present invention is 8.8 k! While it was 9/3Crn,
Conventional sheeting costs 4-2k! ? / 3 cm, which was a low peel strength.

Because of the above, when using the conventional method, it is extremely difficult to obtain an excellent waterproof sheet with a balance between strong peeling strength and water repellency (water absorption prevention property), but when using the method of the present invention, , a high-performance waterproof sheet can be obtained easily and under stable processing conditions.

Procedural amendment (voluntary) September 6, 1985

Claims (1)

[Claims] 1. A method for producing a waterproof sheet by forming a polymer coating on both sides of a fibrous base fabric, which comprises first treating the fibrous base fabric with a water repellent, and then treating both surfaces of the fibrous base fabric with a water repellent. After low temperature plasma treatment,
A method for manufacturing a waterproof sheet, which comprises forming a polymer film on both surfaces. 2. The method according to claim 1, wherein the fibrous base fabric is made of at least one selected from natural fibers, inorganic fibers, regenerated fibers, semi-synthetic fibers, and synthetic fibers. 3. The method according to claim 1, wherein the water repellent is selected from wax, aluminum soap, zirconium salt, quaternary ammonium salt, N-methylol fatty acid amide, amino resin derivative, fluorine compound, and silicone. 4. The method according to claim 1, wherein the water repellent treatment is performed by an impregnation method, a coating method, or a spraying method. 5. The method according to claim 1, wherein the adhesion of the surface layer of the fibrous base fabric is improved by low-temperature plasma treatment. 6. Low temperature plasma treatment at 0.01 to 10 Torr. 6. The method according to claim 5, which is carried out using low-temperature plasma of a gas that does not have plasma polymerizability under a pressure of . 7. A patent claim in which the gas that does not have plasma polymerizability is selected from helium, neon, argon, nitrogen, nitrous oxide, nitrogen dioxide, oxygen, air, carbon monoxide, carbon dioxide, hydrogen, chlorine, halides, and sulfides. The method described in item 6. 8. The method according to claim 1, wherein the polymer is selected from synthetic resins, synthetic rubbers and natural rubbers. 9. Claim 8, wherein the synthetic resin is selected from polyvinyl chloride, polyurethane, ethylene-vinyl acetate copolymer, isotactic polypropylene, polyethylene, polyacrylonitrile, polyester, polyamide, fluororesin, and silicone resin. Method described. 10. The method according to claim 8, wherein the synthetic rubber is selected from styrene-butadiene rubber, chlorosulfonated polyethylene rubber, polyurethane rubber, butyl rubber, isopropylene rubber, silicone rubber, and fluorine rubber. 11. The method according to claim 1, wherein the polymer coating is formed by a calendering method, an extrusion method, a coating method, or a dipping method.