JPH0641193B2 - Breathable waterproof fabric - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a multi-layered fabric having breathability and waterproofness. More particularly, the present invention is suitable for waterproofing applications such as clothing, especially diaper covers. The present invention relates to a fabric that has breathability, waterproofness that can withstand washing, and that has excellent mechanical strength even when actually worn.

(B) Conventional Technology A conventional waterproof cloth has been manufactured mainly by a method of forming a resin film on the surface of a woven or knitted material by coating. However, this fabric results in sacrificing breathability if it is attempted to ensure sufficient waterproofness. As a solution to this problem, in JP-A-56-26076, a synthetic polymer mainly composed of a polyurethane polymer forms a film in which micropores of micron units are contained, and the micropores are made to communicate with each other to improve air permeability. It is suggested to get. However, with this method, the number of foamed holes per unit area is limited, and in order to obtain sufficient waterproofness, the air permeability must be adjusted.
It has to be 0.5cc / cm ² · sec or less, which is not enough to satisfy the air permeability. Further, in order to uniformly disperse the micropores, there is a drawback that the allowable range of manufacturing conditions is narrow and a long manufacturing process is required.

(C) Problems to be Solved by the Invention The present invention solves these technical problems and enables well-balanced breathability and waterproofness.

Usually, the water released from the human body includes water that is constantly evaporating and sweating that accompanies body temperature control during exercise. The former is about 23g / h · m ² under comfortable temperature and rest, and the latter is over 100cc / h · m ² during intense exercise. As described above, the garment and the oscillating cover made of the conventional waterproof cloth prevent the release of the moisture released from the body to the outside of the cloth. Easy to feel pleasant.

Recently, there is a moisture-permeable waterproof cloth in which a moisture-permeable film is bonded onto a woven or knitted fabric, but since the air permeability is insufficient at 0.5 cc / cm ² · sec or less, the amount of moisture released to the outside of the fabric is not sufficient. Is enough.

On the other hand, the target value of waterproof performance for clothing, especially Oshime cover,
It shows the waterproofness of infants under pressure, and is generally
300~400mmH ₂ O is required.

The object of the present invention is to have a contradictory property, having both breathability and waterproofness, which have been difficult to satisfy at the same time in the past, and there is no damage due to external force during practical use such as washing, and excellent mechanical strength. Providing fabric.

The inventors of the present invention used various knitted fabrics in promoting commercialization, and the water pressure resistance decreased due to the breakage of the water-repellent processed web. Therefore, as a result of intensive studies, the present invention was accomplished by finding the relationship between the elongation rate and the stress of the knitted fabric used on one side or both sides of the web.

(D) Means for Solving the Problems That is, the breathable waterproof fabric according to the present invention has a laminated fabric structure, and one of the layers is a laminated fabric mainly composed of fibers having a single yarn denier of 0.005 to 2.0 d. A fiber structure in which each constituent fiber is entangled in multiple directions, a fiber filling rate is 5 to 30%, and a low elongation woven or knitted fabric is laminated and integrated on one or both sides of a water-repellent processed web. A breathable waterproof fabric having a stress of 2.0 kg / 2.5 cm or more when stretched to the breaking elongation of the web.

The "spine structure" used in the present invention refers to a fiber structure in which one or both surface layers of the web layer are woven or knitted. A web layer without a knitted fabric surface layer has a structure in which laminated constituent fibers are entangled in multiple directions,
The shape easily changes due to external pressure such as washing, and the waterproofness is significantly impaired. At least one side of such a web layer,
Preferably, by laminating and integrating a woven fabric or a knitted fabric on both sides, it is possible to prevent deformation due to external force during practical use such as washing, and prevent deterioration of waterproofness.

The cloth that covers the surface may be knitted or woven, but the stress when the "laminated cloth structure" is stretched to the breaking elongation of the web layer that greatly functions as a waterproof function is practically 2.0 kg / 2.5 cm or more,
It should preferably be 5.0 kg / 2.5 cm or more. The breaking elongation of the web layer referred to here is represented by the elongation at which the water pressure resistance of the web after the water-repellent treatment has started to decrease, and is similar to the maximum stress value when the web alone stretches. That is, in order to obtain the breathable waterproof fabric of the present invention, the stress when the knitted fabric is stretched to the web breaking elongation is (A) = (2.0 kg / 2.5 cm) − (the maximum stress value of web stretching) or more. is necessary. Therefore, when selecting a knitted fabric, the breaking strength and elongation of the web used is determined by an elongation test. Next, a knitted fabric having a value equal to or higher than the stress represented by the above formula (A) is selected from the value of the elongation. If the value is less than the value of (A), the web will be damaged and the water pressure resistance will decrease during practical use. In addition, the knitted and woven fabric is the one that shows the maximum value before reaching (A). or,
The method of increasing the (A) value of the knitted fabric is to reduce the degree of knitted fabric, and the method is to increase the density of the knitted fabric, to make the tissue hard to move with spun yarn-like fluff, and to insert the knitted fabric. It is conceivable that the technique may be applied or a method of reducing elongation in finishing may be considered, but the invention is not limited to this. The material and basis weight of the knitted fabric are preferably matched to the intended use and are not particularly limited.

Examples of the “web” in the present invention include, but are not limited to, a nonwoven fabric produced by making short fibers, a long fiber nonwoven fabric obtained by laminating melt-spun fibers, a needle punched nonwoven fabric of a carding web, and the like. In particular, a melt-blown web is preferred. This web is
This is because the fibers are fine denier, have a uniform basis weight and thickness, and are less likely to cause pinholes. On the other hand, the fine denier web may be obtained by dissolving and removing one of the sea-island fibers composed of two components such as a polyamide component and a polyester component. The weight of the web is not particularly limited,
30 to 120 g / m ² is preferable.

As fibers constituting the web, those having a single fiber denier of 0.005 to 2.0 denier, preferably 0.01 to 1.0 denier are used. If it is less than 0.005 denier, the single fiber strength is low, and the handleability during subsequent processing is poor. Further, the close contact between the single fibers is large, and sufficient air permeability cannot be obtained. On the other hand, if it exceeds 2.0 denier, breathability is improved, but sufficient waterproofness cannot be obtained.

The fiber packing ratio α (%) represented by (ρ ′ / ρ) / 100 of the web layer [ρ ′ is the apparent density of the fiber structure, ρ is the true density of the fiber] is 30 ≧ α ≧ 5, preferably Is in the range of 25 ≧ α ≧ 10. That is, if the filling rate is less than 5%, the fiber gap becomes large and sufficient waterproofness cannot be obtained. If the filling rate exceeds 30%, sufficient air permeability cannot be obtained.

As the method of bonding the surface layer and the web layer in the present invention, a method of spraying a low melting point resin such as a polyamide resin between the two layers, a method of thermocompression bonding, a method of entanglement by needle punching, and a heat fusion property were used. Any method such as a welding method or a sewing method may be used. For example,
Low-melting polyamide resin is used, 100 per square inch
Dot-like spraying before and after the mesh and bonding with a heat press machine can bond without damaging the feel of the web layer and the surface material of the front and back, and without impairing the air permeability and waterproof effect.
The peel strength is required to be 400 to 800 g / inch to withstand washing.

In the “water repellent treatment” according to the present invention, the entire laminate or at least the web layer is treated. The water repellent may be applied by a usual method such as a putting method or a dipping method. A sufficient water repellent effect can be obtained when the amount of the water repellent attached is about 1% to 10 based on the weight of the fiber. Further, after applying the water repellent, high temperature heat treatment is performed in order to promote fixation of the water repellent to the fiber. The temperature and time of the heat treatment may be appropriately selected depending on the water repellent and the application. For example, when a fluorine-based water repellent agent is used for polyester fibers, heat resistance at 180 ° C. for about 1 minute provides waterproofness that can withstand washing. As a water repellent,
It has durability against washing and rain, and examples thereof include fluorocarbon resins such as acrylic acid perfluoroalcohol ester and fatty acid amide derivatives such as fatty acid amide methylol compounds.

(E) Examples Next, the present invention will be specifically described with reference to the following examples.

Example 1 Single yarn denier 0.03d obtained by melt blow method,
A polyethylene terephthalate fiber web having a basis weight of 30 g / m ² was subjected to a relaxation treatment with a Wins dyeing machine, then immersed in a bath according to the following treatment 1 by a putting method, and then uniformly squeezed with a mangle machine at a squeezing ratio of 100%. , Dried at 110 ℃ for 2 minutes,
A heat treatment was performed at 180 ° C. for 1 minute to make the filling rate 15%. The web breaking elongation at this time is 20% vertical, 30% horizontal, and bias
It was 30%.

On the other hand, a polyethylene terephthalate fiber yarn 50 denier / 48 filament is knitted with a tricot machine using a knit structure satin and a high density of 170 g / m ² with a fabric weight, and is subjected to ordinary dyeing and water repellent processing by a pin tenter machine. In the final setting process, the stress at the time of web breaking elongation is 5.0kg / 2.5c vertically
m, horizontal 1.0, 2.0 and 5.0 kg / 2.5 cm, bias 3.0 kg / 2.
The finished fabric width was changed to be 5 cm. In addition, 100 points of polyester hot melt resin on one side
Dots were sprayed at 12 ± 1 g / m ² at intervals of square inches.

Next, using a heating press machine, stack the web and knitted fabric, and 1.
Adhesion was performed at 130 ° C. for 12 seconds under a pressure of 5 kg / cm ² .

Remedy 1 Asahi Guard AG710 (Made by Asahi Glass) Water repellent 3% Eretat 930 (Made by One Company) Antistatic agent 1% Isopropanol (Penetrant) 2% Water 94% Breathability of the obtained waterproof cloth and 2.0 kg load Repeated extension 50
Table 1 shows the comparison results of the water pressure resistance after the rotation. The water pressure resistance after repeated stretching was evaluated as ◯ when the water pressure was 400 mmH ₂ O or more, and as x when the water pressure was 400 mmH ₂ O or more.

Example 2 Single-fiber denier produced by the melt-blowing method is 0.00
Polyester fiber web mainly composed of 3, 0.005, 0.03, 0.3, 1.0, 2.0 and 3.0 denier fibers (Basis weight 30 g /
1 to 3 sheets of m ² ) were laminated, and water repellency processing and adhesion processing similar to those in Example 1 were performed to compare breathability and waterproofness. The results are shown in Table 2. The water pressure resistance after washing 30 times is 400 mmH ₂ O.
The above time was evaluated as ◯, and the following time was evaluated as x.

In Experiment Nos. 4 and 10, the morphological change due to washing was large, and sufficient water resistance could not be obtained.

Example 3 A single fiber denier 0.03 denier polyester fiber having a web weight of 30 g / m ² was used and pressure-processed so that the fiber filling rate was 3, 5, 11, 30 and 40%. The results are shown in Table 3. The results of water permeability and waterproofing similar to those in Example 1 were performed, and the air permeability and waterproofness were compared. In addition, water resistance after washing 30 times is 400 mmH ₂ O or more is ◯, less is ×, and if the texture is unsuitable for clothing ×
Evaluated as.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B32B 5/02 7016-4F 7/02 101 9267-4F

Claims (1)

[Claims] 1. A fiber structure in which a low elongation knitted fabric is laminated and integrated on one or both sides of a water-repellent processed web having a single yarn denier of 0.005 to 2.0 denier and a fiber filling rate of 5 to 30%. The breathable waterproof fabric, wherein the stress of the fiber structure when stretched to the breaking elongation of the web is 2.0 kg / 2.5 cm or more.