JPS5844789B2 - Method for manufacturing non-breathable waterproof fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a non-breathable waterproof fabric.

More specifically, the present invention relates to a non-breathable waterproof fabric using a relatively coarse density base fabric and a method for manufacturing the same.

Conventional knitted fabrics, especially knitted fabrics made of synthetic fibers, more specifically knitted fabrics made of synthetic fiber spun yarn, as the base fabric,
A method is known for producing a non-breathable waterproof fabric by forming a thin film layer of a waterproofing agent mainly composed of a hydrophobic polymer material, for example, polyvinyl chloride, on at least one side of this base fabric.

In order to form the above-mentioned non-breathable waterproof layer, a pre-prepared non-breathable film of a hydrophobic polymer material is attached to one or both sides of the base fabric with an adhesive or by heat fusion. A treatment solution containing a pre-prepared hydrophobic polymer material is impregnated into the base fabric or applied to one or both sides of the base fabric and solidified to form a non-breathable waterproof material. Methods of forming layers are known.

In the latter method of impregnating or coating the base fabric with a waterproofing liquid, the waterproofing layer solidified from this waterproofing liquid often has pinholes, which may result in unsatisfactory waterproofing performance of the waterproofing layer. there were.

In order to prevent such defects, the density of the base fabric must be relatively dense, that is, each yarn making up the knitted fabric of the base fabric must be as close as possible to its neighboring yarns. are required to do so.

However, such high-density knitted fabrics are expensive;
Moreover, since the waterproof fabric is heavy and has low flexibility, it is not only difficult to handle the obtained waterproof fabric, but also the product is expensive.

Therefore, attempts have been made to use a base fabric made of a knitted fabric with a relatively low density, and to impregnate or coat the base fabric several times with a waterproofing liquid containing a hydrophobic polymer material.

However, this method not only increases the processing cost but also increases the thickness of the waterproof layer formed, which increases the weight of the resulting waterproof fabric and reduces its flexibility. Ta.

Moreover, the waterproof fabric obtained by this method has a large thickness of the waterproof layer, and therefore has the disadvantage that the appearance and feel of the base fabric are completely lost.

An object of the present invention is to provide a method for manufacturing a waterproof fabric that has good waterproof performance using a relatively thin waterproof layer even when a base fabric made of a knitted fabric with a relatively low density is used. be.

The method for producing a non-breathable waterproof fabric of the present invention involves preparing a knitted fabric made of a large number of threads and impregnated with a thermoplastic polymer material, and processing the knitted fabric impregnated with the polymer material. Pressing to flatten the yarn together with the polymer material to prepare a base fabric, and forming an impermeable waterproof layer made of a hydrophobic polymer material on at least one surface of the base fabric. It is something to do.

In one embodiment of the waterproof fabric of the present invention shown in FIG. 1 (plan view of the waterproof fabric) and FIG. It is cloth.

Each yarn (warp, weft) 2, 3 in this base fabric 1 is impregnated with a thermoplastic polymer material, and each yarn is flattened together with this polymer material. It has a flat cross section like the warp threads 2 shown in the figure.

For this reason, each yarn is very close to the yarn adjacent to it, so that the inter-yarn gaps in the base fabric 1 are extremely small.

A non-breathable waterproof layer 4 is formed on one side of the base fabric 1.

The threads of the base fabric may be made of any fiber as long as it does not impair the performance of the waterproof fabric, but synthetic fibers are generally preferred.

This synthetic fiber is not particularly limited, but it is generally preferably selected from water-insoluble polyvinyl alcohol fiber (vinylon), polyester fiber, and polyamide fiber.

These yarns may be multifilament yarns, but are preferably spun yarns.

The thermoplastic polymer material impregnated into the yarn is preferably selected from polyvinyl chloride, ethylene-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer, polyurethane, chlorosulfonated polyethylene, acrylic resin, and the like. It is preferable that at least one member is included.

The polymeric material may also contain plasticizers, stabilizers, colorants, fillers, water repellents, and the like.

In general, polymer materials have a diameter of 2 to 100 φ relative to the yarn weight.
It is preferable that the yarn is impregnated in an amount within the range of .

In a yarn impregnated with a polymer material, the polymer material may penetrate into the center of the yarn, but it is necessary that the polymer material penetrates at least into the outer peripheral layer of the yarn.

That is, in the flattened yarn, it is necessary that the polymer material forms a matrix at least in the outer peripheral layer portion of the yarn, and that the fibers are held and fixed within this matrix.

The polymeric material with which the yarn is impregnated may be a foam-containing material.

Some or all of the cells in this foam-containing material may be compressed.

In the method of the present invention, the weight of the impermeable waterproof layer is preferably within the range of 25 to 100 φ relative to the weight of the base knitted fabric.

In the method of the invention, first a knitted fabric consisting of yarn impregnated with a thermoplastic polymeric material is prepared.

A knitted fabric impregnated with a polymer material may be produced by first impregnating a yarn with a polymer material and then knitting or weaving this yarn, or alternatively, a knitted fabric impregnated with a polymer material may be produced by impregnating a yarn with a polymer material and then knitting or weaving this yarn. It may also be obtained by impregnating a material.

When the yarn is impregnated with a polymeric material, the amount of this polymeric material is preferably in the range from 2 to 100% based on the weight of the yarn.

In addition, when a polymeric material is impregnated into a knitted fabric, the amount of this polymeric material is 2 to 100% based on the weight of the knitted fabric.
It is preferable that it is within the range of .

The knitted fabric impregnated with polymeric material is compressed (pressed) and the yarns are flattened together with the polymeric material with which they are impregnated.

That is, when a fabric consisting of warp yarns 2a and weft yarns 3a having a normal cross-sectional shape as shown in FIG. The warp yarns 2 and weft yarns 3 are flattened.

As a result of this flattening, the warp and weft yarns each increase in width, and as a result, the distance between each yarn and the yarn adjacent to it becomes extremely narrow, and the breathability of the resulting base fabric is considerably reduced. ing.

The above-mentioned pressurizing step can be performed using a calender roll.

The pressing step may also be carried out after or while heating the knitted fabric impregnated with the polymeric material to low heat, preferably from 50 to 200°C.

Such heating increases the plasticity of the polymer material and makes it easier to flatten along with the threads.

The polymeric material impregnated into the textile may contain blowing agents.

In this case, the polymer material-impregnated knitted fabric is subjected to a foaming step before the pressing step.

The foaming process varies depending on the type of foaming agent, but generally 8
It is carried out by heating the knitted fabric impregnated with polymeric material from 0 to 220°C.

It is preferable that the bubbles generated at this time are independent bubbles, and that the foam-containing polymer formed does not have water absorbency.

Foaming as described above significantly increases the apparent cross-sectional area (diameter) of the yarn.

That is, as schematically shown in FIG. 4, when the foaming agent-containing polymer material impregnated thread 6 is subjected to the foaming process,
Its apparent cross-sectional area (diameter) is increased, and it becomes a cell-containing yarn 7.

A large number of air bubbles 8 are formed in the polymer material in this yarn 7.

Next, when this cell-containing yarn is flattened by a pressurizing process, the width of the obtained flattened yarn 9 is even larger than that of the cell-containing yarn 8.

Further, by this pressurizing step, some or all of the bubbles are compressed and crushed to become flattened bubbles 10, or disappear.

The threads in the base fabric obtained in this way have a particularly markedly increased width, the air permeability of the base fabric is reduced and it has a markedly flat surface.

The flat surface of the base fabric obtained as described above is suitable for forming a pinhole-free impermeable waterproof layer with a small amount of hydrophobic polymeric material.

The blowing agent can be appropriately selected depending on the polymer material used, but in general, azodicarbonamide, azobisformamide, acidic sodium carbonate, dinitrolipentamethylenetetramine (DPT), azobisisobutyro Foaming agents such as nitrile, para-toluenesulfonyl hydrazide, toluenesulfonylhydrazide, organic hydrazine derivatives, lydium polyhydride, potassium polyhydride, hydrazide compounds, DPT urea co-activator combination, etc. foam when heated at 80 to 220°C. Therefore, it is suitable for the method of the present invention.

A waterproofing liquid containing a conventional hydrophobic polymeric material is applied onto one or both sides of the base fabric obtained as described above.

Examples of such waterproof polymer materials include polyvinyl chloride.
ethylene-vinyl acetate copolymer, vinyl chloride-
At least one polymer material selected from vinyl acetate copolymer, polyurethane, chlorosulfonated polyethylene, acrylic resin, etc. is used.

The waterproofing liquid may be in any form such as a solution, emulsion, or paste, and the application method may be any of the usual methods, such as dipping, spraying, coating knife method, coating roll method, and brush coating method. It may be.

The weight of the non-breathable waterproof layer is 25% of the weight of the base knitted fabric.
It is preferably within the range of 100% to 100%.

When the non-breathable waterproof layer is formed on one side of the base fabric, a normal breathable waterproofing agent such as metal soap, wax, silicone waterproofing agent, zirconium waterproofing agent, etc. may be applied to the opposite side. .

Further, the surface of the impermeable waterproof layer may be treated with a drip-proofing agent, an antifouling agent, or other processing agent.

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

Example 1 A 208/1 vinylon spun yarn was impregnated with a thermoplastic polymer material having the following composition at a solid weight ratio of 5φ to the yarn weight.

Acrylic acid ester resin 100 parts (trade name Brimar HA) Foaming agent hydrazide compound 3 parts (trade name Cellulon H: Marusho Kogyo) Water repellent agent methylhydrogen polysiloxane 3 parts (trade name Silicone resin: Shin-Etsu Chemical) In this way A plain weave having the following structure was woven using the obtained polymer material-impregnated vinylon spun yarn.

The obtained fabric has a basis weight of 125 g/rri' and a thickness of 0.3
2y□, and the yarn gap was relatively large.

When this fabric was heated to 120°C for 3 minutes to foam the polymer material in the threads, the thickness of the fabric was 0.72 m/cm.
It increased to rrL.

When this foamed fabric was immediately pressed with a calendar roll, the thickness of the fabric was reduced to 0.35 m/rrL, the threads were flattened, and the gaps between the threads were significantly reduced.

The base fabric obtained as described above was immersed in a waterproofing solution having the following composition, squeezed with a mangle, and this operation was repeated twice.

When this fabric was dried at 190°C to solidify the waterproofing agent, a 25 og/m solidified waterproof layer was formed on both sides of the fabric.

In other words, the weight of the obtained waterproof fabric is 375g/77+''
It was relatively lightweight.

However, no pinholes were observed in the waterproof layer of this waterproof fabric, and its water pressure resistance was more than 150 (h++mH2O), which was satisfactory.

Furthermore, the water pressure resistance when rubbed by hand was also satisfactory.

For comparison, a waterproof fabric similar to that described above was produced by omitting the operation of impregnating the yarn with a polymer material and the pressure flattening operation among the same operations as above.

However, the waterproofing liquid dipping and mangle squeezing operation was repeated three times, and the fabric weight of the resulting waterproof fabric was 450 g/m.

The comparative waterproof fabric obtained had an unnecessarily high surface gloss, an unsatisfactory water pressure resistance of about 1200 mmH2, and a considerable number of pinholes were observed here and there.

In addition, partial slipping of the fabric was observed during mangle drawing, which caused operational difficulties.

Like this comparison waterproof fabric, a satisfactory waterproof fabric is produced using 20S/1 vinylon spun yarn, but without impregnating the yarn with a polymer material and without applying pressure flattening to the base fabric. In order to achieve this, a higher density than

Example 2 The same operation as in Example 1 was performed.

However, the polymer material impregnated into the yarn does not contain a blowing agent;
The amount of polymer material impregnated with respect to the yarn weight was 15%.

The obtained waterproof fabric had a basis weight of 39 ogim, and its water pressure resistance was satisfactory at 1500 rnrnH20 or higher.

Example 3 A plain woven fabric having the following structure was woven using 14 S/1 polyester spun yarn.

The obtained fabric had a basis weight of 17 ogim and a thickness of 0.42 T/rrL after scouring.

This fabric was subjected to dipping and mangle drawing with a polymer material having the following composition.

The impregnated fabric was dried at 165° C. to gel the polyvinyl chloride, and was found to be impregnated with 20% solid polymer material based on the weight of the fabric.

The thickness of this fabric was 0.44"/.

Next, this fabric was heated at 200°C for 1 minute to foam, and the thickness of the fabric was 0.96'rr/frL.

Next, the foamed fabric was immediately subjected to Calorie compression using a calendar roll, and the thickness of the fabric was 0.45.

This fabric was subjected to the same waterproofing treatment as in Example 1.

The obtained waterproof fabric was lightweight with a basis weight of 3559/m2, but no pinholes were observed in the waterproof layer, and its water pressure resistance was satisfactory at 1500 mmH20 or higher.

Example 4 A plain woven fabric having the following structure was woven using a 108/1 vinylon spun yarn.

The basis weight of this plain woven fabric after scouring is 200 g/m,
Its thickness was 0.45rr/rrL.

This fabric was subjected to the same operation as in Example 3.

However, the thickness of this fabric after being impregnated with the polymer material is 0.48%.
The thickness after foaming is 0.987r/rfL,
Thickness after calender roll treatment is 0.49″m/rrL
Met.

In addition, the fabric weight after forming the waterproof layer was light, 400 g/m, but no pinholes were observed in the waterproof layer, and the water pressure resistance was 1.
500 mmH20 or more was satisfactory.

This waterproof fabric had a thick feel, had good repellency, was flexible, had a cotton-like appearance, and had no unpleasant luster, making it a desirable product.

The method of the present invention is carried out as described above, but the method of the present invention is different from the conventional method of simply calendering the base fabric knitted fabric greige before forming the waterproof layer. Moreover, addition of steps such as calender treatment after forming the hydrophobic polymer material film can be optionally selected.

[Brief explanation of the drawing]

FIG. 1 is an explanatory plan view showing the structure of the base fabric in one embodiment of the waterproof fabric obtained by the method of the present invention, and FIG.
The figure is an explanatory cross-sectional view of one embodiment of the waterproof fabric obtained by the method of the present invention, FIG. 3 is an explanatory cross-sectional view of the front fabric of the base fabric used in the method of the present invention, and FIG. FIG. 2 is an explanatory diagram showing changes in the cross-sectional shape of the yarn due to foaming and pressure flattening of the yarn impregnated with a foaming agent-containing polymer material in the method of the present invention. 1...Base fabric, 2...Flattened warp, 3.
...Flattened weft, 4...Waterproof layer, 2a.
... Warp yarn before flattening, 3a ... Flattened front yarn, 6 ... Blowing agent-containing polymer material impregnated yarn, 7
...Foamed yarn, 8...Bubble, 9...
...Flattened yarn, 10...Flattened air bubbles.

Claims (1)

[Scope of Claims] 1. A knitted fabric made of a large number of threads impregnated with a thermoplastic polymer material is prepared, and the knitted fabric impregnated with the polymer material is pressurized to remove the threads. A base fabric is prepared by flattening the strips with the polymeric material, and a non-breathable waterproof layer of the hydrophobic polymeric material is formed on at least one side of the base fabric. A method for producing a non-breathable waterproof fabric, comprising: 2. The yarn knitted fabric impregnated with the polymer material is prepared by knitting or weaving yarn impregnated with the polymer material.
A method according to claim 1. 3. The method according to claim 1, wherein the yarn knitted fabric impregnated with the polymer material is prepared by impregnating the yarn knitted fabric made of the yarn with the polymer material. 4. The method of claim 2, wherein the amount of polymeric material impregnated into the thread is in the range of 2 to ioo% relative to the weight of the thread. 5. The method of claim 3, wherein the amount of polymeric material impregnated into the knitted fabric is in the range from 2 to 100% relative to the weight of the yarn. 6. The method according to claim 1, wherein the pressurizing step is performed using a calender roll. 7 The pressurizing step may cause the polymer material-impregnated knitted fabric to
The method according to claim 1, which is carried out after or during heating to 0 to 200°C. 8. A patent in which the polymer material impregnated into the threads of the knitted fabric is impregnated with a foaming agent, and the knitted fabric impregnated with the polymer material is subjected to a foaming process before the Calo pressure process. A method according to claim 1, 6 or 7. 9 The foaming step may cause the polymer material impregnated knitted fabric to
9. The method according to claim 8, which is carried out by heating to between 220°C and 220°C. 10. The method according to claim 1, wherein the weight of the non-breathable waterproof layer is within a range of 25 to 100φ relative to the weight of the base fabric.