JP2002000316A - Hot-melt adhesive plane faster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hot-melt adhesive plane fastener to a polyolefin substrate. SOLUTION: The hot-melt adhesive plane fastener is characterized by melt- coating in sequence with a layer composed of a melt adhesive A having a melting point of 120-180 deg.C and another layer composed of a melt adhesive B having a melting point of 80-140 deg.C on the back face of the plane fastener, where the adhesive A has a higher melting point than that of the adhesive B.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface fastener that can be thermally fused to an adherend, and more particularly to a surface fastener that can be thermally fused (hereinafter, referred to as "fusion") to a polyolefin-based adherend.

[0002]

2. Description of the Related Art A hook-and-loop fastener is made of a knitted or woven fabric in which a hook-shaped engaging element or a mushroom-shaped engaging element and / or a plurality of loop-shaped engaging elements engaged with these engaging elements are provided on a woven base cloth. Surface fasteners and molded surface fasteners obtained by extrusion or injection molding, and both products are used according to their features. Woven hook-and-loop fasteners are widely used for various applications due to their engaging performance and flexibility due to the weaving structure. Molded hook-and-loop fasteners are low in price and have high engaging force, so they are used for engaging members of industrial materials, diapers and sanitary goods. Used in disposable products.

The present invention relates to a technique for joining these surface fasteners to an adherend. When a knitted surface fastener is attached to a fabric, usually, sewing with a thread or joining with various adhesives is performed. On the other hand, there is also a usage method in which a woven hook-and-loop fastener is bonded to a resin film or sheet, but in this case, if the adhesiveness between the woven hook-and-loop fastener and the resin film is inappropriate, the adhesive strength is reduced. Inferior to practical use. Since the molded surface fastener cannot be sewn, it is joined by an adhesive or fusion.

[0004] Conventionally, as a resin film or sheet, polyvinyl chloride resin having excellent adhesiveness to a hook-and-loop fastener has been frequently used. However, when polyvinyl chloride resin is incinerated, a chlorine-containing gas is generated. It is also said to be. Therefore, it has been proposed to use a film or sheet made of a polyolefin-based resin that does not generate toxic gas in place of the polyvinyl chloride resin and bond a hook-and-loop fastener to this film or sheet. Since the affinity and the adhesiveness are inferior, there is a problem that it is strongly bonded to the hook-and-loop fastener.

To solve this problem, various types of adhesives and fusion agents have been proposed, but very few have excellent adhesive strength and can withstand practical use. In addition, a two-layer film of a thermoplastic resin film of the same quality as the surface fastener and a polyolefin film having a lower melting point than the thermoplastic resin film is used as a heat-sealing film. Gazette and JP 1
It has been proposed in Japanese Patent Application Publication No. 1-253210. This method discloses a technique for directly fusing a two-layer film to a surface fastener.

[0006]

However, the above-mentioned method involves preparing a two-layer film, slitting the two-layer film to the same width as the hook-and-loop fastener, and the two-layer film having a different hygroscopic property. May need to be bent, a fusing device must be installed, and the heating conditions must be controlled and the thickness of the two-layer film must be adjusted so that the surface fastener and the two-layer film can be fused well. However, the production process is complicated and expensive, and there are many problems in practicality. Further, even if the two-layer film is directly fused to the hook-and-loop fastener, the adhesion is not sufficient, and the film is easily peeled off from the bonding surface, which is not a practical technique. An object of the present invention is to solve the above problem and to provide a surface fastener for fusion in which adhesion between a surface fastener and an adherend such as a polyolefin-based resin film or sheet (hereinafter referred to as a polyolefin-based adherend) is improved. I do.

[0007]

That is, the present invention provides:
On the back surface of the hook-and-loop fastener, a layer made of a molten adhesive A having a melting point of 120 to 180 ° C and a molten adhesive B having a melting point of 80 to 140 ° C
Are successively melt-coated, and the adhesive A
Is a resin having a melting point higher than that of the adhesive B. Preferably, in such a surface fastener, the adhesive A has a melting point of 10 to 100 from the melting point of the adhesive B. C. is a resin having a high melting point. As a preferred example, in the above-mentioned surface fastener for fusion, the surface fastener has a coating layer on the back surface thereof, and the coating layer is a layer comprising the molten adhesive A. And the case where the layer made of the molten adhesive B is sequentially melt-coated, and the surface fastener has no coat layer on the back surface, and the layer made of the molten adhesive A and the molten adhesive B are formed on the back surface of the surface fastener. In which the layers are sequentially melt-coated directly.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The hook-and-loop fastener used in the present invention is a knitted hook-and-loop fastener or a molded hook-and-loop fastener as described above. The hook-and-loop fastener includes a base cloth and a hook-shaped engaging element or a mushroom-shaped engaging element (hereinafter referred to as a hook-shaped engaging element) attached to one surface thereof by a weaving method. And a plurality of loop-shaped engaging elements attached by a weaving method, and those having both hook-shaped engaging elements and loop-shaped engaging elements on the same woven / knitted surface. A hook-and-loop fastener having both a hook-shaped engaging element and a loop-shaped engaging element on the same woven or knitted fabric surface has been developed and put into practical use by the present applicant. The hook-and-loop engaging element which replaces the hook-and-loop engaging element with the hook-like engaging element instead of the hook-and-loop non-woven fabric is also included in the hook-and-loop fastener of the present invention.

The fibers constituting the hook-and-loop fastener of the present invention are:
A thermoplastic fiber may be used, but a polyamide fiber or a polyester fiber is preferable in terms of strength, elasticity, deformation recovery property and the like. In the hook-and-loop fastener of the present invention, since the base cloth, the hook-shaped engaging elements and the loop-shaped engaging elements are formed by a weaving method, the fibers of the base cloth and the fibers of the engaging elements are not sufficiently fixed. In the process, the fibers of the base fabric and the engaging element move, and the position of the engaging element may move slightly.
Since the hook-and-loop fastener of the hook-shaped engaging element first forms a large number of loops with a filament on the base cloth and cuts a part of the side thread of each loop with a minute movable blade to form the hook-shaped engaging element. It is important to fix the position of the loop, and it is necessary that the base cloth and the hook-shaped engaging element are sufficiently fixed. Further, it is necessary to prevent the hook-shaped engaging element from coming off from the base cloth by repeating attachment and detachment with the loop-shaped surface fastener.

In the case of the loop-shaped engaging element, it is not necessary to fix the position more strictly than in the case of the hook-shaped engaging element. However, a uniform arrangement is desirable in order to have a uniform engaging force with the hook-shaped engaging element. Since it is desirable that the loop-shaped engaging element does not move or slip off from the base fabric by repeatedly attaching and detaching the loop-shaped engaging element, it is necessary to fix the fibers of the base fabric and the engaging element fibers.

[0011] From the above problems, it is desirable that a knitted surface fastener be provided with a coat layer on the back surface of the base fabric, that is, the surface having no engaging element. The coat layer adheres and fixes the fibers of the base fabric and the fibers of the hook-shaped or loop-shaped engaging element. The resin used for the coat layer is preferably a resin having an affinity for the constituent fibers of the hook-and-loop fastener. Polyurethane-based resins are preferably used because they have excellent affinity and adhesion to polyamide or polyester-based fibers constituting the surface fastener. The polyurethane resin used in the present coat layer preferably has a high degree of crosslinking. The degree of crosslinking is adjusted by the ratio of the trifunctional or more functional compound in the isocyanate compound and / or the hydroxyl group-containing compound. Further, for a hook-and-loop fastener composed of polyester fibers, a polyester coat layer is preferable.
The coating amount of the coat layer is preferably ²⁰ to 50 g / m ² .

In order to fuse a surface fastener having the above-described coating layer and a polyolefin-based adherend, that is, a film or sheet of a polyolefin-based resin such as polyethylene, polypropylene, or a copolymer thereof, the surface fastener is coated with a coating layer. It is necessary to provide a fusing agent layer by sequentially fusing a layer made of the fusing adhesive A having a melting point of 120 to 180 ° C. and a layer consisting of the fusing adhesive B having a melting point of 80 to 140 ° C. By selecting the molten adhesive A and the molten adhesive B and sequentially applying the adhesive to the back surface of the hook-and-loop fastener, a good molten adhesive layer can be provided to the hook-and-loop fastener. Conventionally, in order to provide a two-layered molten adhesive on a hook-and-loop fastener, it has been considered preferable to prepare a laminated film and fuse or bond the laminated film to the hook-and-loop fastener. However, as described above, the use of the laminated film requires many steps and adjustments, and has many problems. On the other hand, the present invention in which two types of molten adhesives are directly melt-coated on a surface fastener solves those problems,
A high quality fusion surface fastener can be efficiently provided.

The molten adhesive A used in the present invention has a melting point of 12
A resin having a temperature of 0 to 180 ° C, a polyurethane resin,
Polyamide resins, polyester resins and the like are preferred. If the melting point is less than 120 ° C., coating irregularities are likely to occur,
If the temperature exceeds 0 ° C., the melting point of the surface fastener is close to that of the surface fastener. Melt adhesive B used in the present invention
Is a resin having a melting point of 80 to 140 ° C., and is preferably a polyolefin resin. Specific examples of the polyolefin-based resin include a polyethylene-based copolymer and a polypropylene-based copolymer, and an ethylene-vinyl acetate-based copolymer is a particularly preferred example. If the melting point is lower than 80 ° C., coating unevenness tends to occur. If the melting point is higher than 140 ° C., the layered portion with the molten adhesive A becomes non-uniform, and the melting point of the polyolefin-based adherend is close to that of the adherend. It is not preferable because the performance may be deteriorated.

The above-mentioned molten adhesive A preferably has a melting point higher by 10 to 100 ° C. than the melting point of the molten adhesive B,
More preferably, it has a melting point higher by 20 to 80 ° C. When the melting point difference is less than 10 ° C., the molten adhesive remelts when applying the molten adhesive B to the molten adhesive A, and a good two-layer structure cannot be formed. Insufficient fusion between the agents makes it impossible to form a good two-layer structure. By selecting a molten adhesive that satisfies such conditions, it has become possible to apply a laminated molten adhesive by sequentially applying the two adhesives to the back surface of the hook-and-loop fastener. In the present invention, the thickness of the layer made of the molten adhesive A and the thickness of the layer made of the molten adhesive B are both preferably in the range of 60 to 200 μm.

As the method of melt coating, known methods can be used without limitation, for example, a coating T-die method or a roll coating method, or a method combining a coating T-die method and a roll coating method.

The method for forming the molten adhesive layer of the present invention is as follows.
In addition to the above-described hook-and-loop fastener having a coat layer, the present invention can be applied to a hook-and-loop fastener having no coat layer and a molded hook-and-loop fastener. Because the affinity of the molten adhesive selected in the present invention and the constituent resin of the hook-and-loop fastener is excellent, the molten adhesive A may have the function of the coat layer of the hook-and-loop fastener in some cases, and it is difficult to bond the molded hook-and-loop fastener. This is because good adhesiveness is exhibited even on the film-like back surface.

The surface fastener for fusion obtained according to the present invention is obtained by joining the layer made of the molten adhesive B to a polyolefin-based adherend and pressing the layer at the melting point of the molten adhesive B or at a temperature near the melting point. We fuse. For heat fusion, a heating roller, an ultrasonic fusion device, a high frequency fusion device, or the like can be used. The fusion between the surface fastener and the polyolefin-based adherend includes, in addition to the entire surface fusion, fusion of the peripheral portion of the surface fastener, a line-like, grid-like, or dot-like shape provided at an appropriate interval with respect to the surface. Fusion can be performed by partial fusion. In addition, it is necessary to perform the fusion at a temperature and a pressure condition that do not damage the engaging element attached to the surface fastener.

[0018]

EXAMPLES The present invention will be further described with reference to the following Examples, but it should not be construed that the invention is limited thereto.

EXAMPLE 1 A 330-denier monofilament made of nylon-66 as a hook yarn, and 4.6 made of nylon-66 as a base cloth.
Polyurethane coating layer (Chrisbon AH-825 Dainippon Ink & Chemicals, Inc .: 3D cross-linking type, coating amount (solid content)) on the back surface of the base fabric of the hook-and-loop fastener composed of multifilament yarns in which 24 denier filaments are bundled 35
g / m ² ), a hot-melt resin of nylon 12 having a melting point of 140 ° C., which is a polyamide-based resin, is applied at 100 g / m ² as a molten adhesive A, and then a polyolefin-based resin is used as a molten adhesive B. , An EVA hot melt resin having a melting point of 100 ° C and an ethylene-vinyl acetate copolymer containing 25% of vinyl acetate units was applied at 100 g / m ² to obtain a surface fastener of the present invention. The obtained surface fastener was heat-sealed to various olefin adherends (films) using a high-frequency welder (Fuji Electric Co., Ltd.), and the adhesive strength was measured. The results are shown in Table 1.

[0020]

[Table 1]

From Table 1, it was found that various olefin adherends were fused well enough to destroy the material. In addition, the adhesive force is JI
It was measured according to the 180-degree peeling method of SZ-0237.

COMPARATIVE EXAMPLE 1 Polyurethane was applied to the back of the base fabric of the same surface fastener as in Example 1.
With the same coating layer as in Example 1
Containing 25% vinyl acetate as a reolefin resin,
EVA hot melt resin of Tylene-vinyl acetate copolymer
100 g / m ^TwoApply and obtain surface fastener for fusion
Was. The obtained surface fastener was subjected to high frequency
Heat welding was performed with a welder, but polyurethane
Easily peels off at the interface between the heat layer and the EVA hot melt resin
I can not create a fusible surface fastener
Was.

[0023]

According to the present invention, a surface fastener which can be fused to a polyolefin-based adherend is provided.

Claims (4)

[Claims] 1. A melting point of 120 to 1 on a back surface of a hook-and-loop fastener.
80 ° C. layer made of molten adhesive A and melting point 80-140 ° C.
Layers of the molten adhesive B are sequentially melt-coated,
And the adhesive A is a resin having a higher melting point than the adhesive B. 2. The method according to claim 1, wherein the adhesive A has a melting point of the adhesive B of 10 to 10.
The fusion surface fastener according to claim 1, which is a resin having a melting point higher by 100 ° C. 3. The hook-and-loop fastener has a coat layer on the back surface thereof, and a layer made of the molten adhesive A and a layer made of the molten adhesive B are sequentially melt-coated on the coat layer. 3. The fusion surface fastener according to item 2. 4. The hook-and-loop fastener has no coat layer on the back surface,
The surface fastener according to claim 1 or 2, wherein a layer made of the molten adhesive A and a layer made of the molten adhesive B are directly melt-coated directly on the back surface of the surface fastener.