JPH0355582B2 - - Google Patents

Description

[Detailed Description of the Invention] a. Industrial Fields of Use The present invention fixes the arrangement of a large number of yarn groups, uses them as an aggregate, and further uses it as a weft web of a weft/warp orthogonal nonwoven fabric. As a special use, it is also used in adhesive nonwoven fabrics with threads in the vertical direction.

b. Prior Art and Problems to be Solved by the Present Invention In recent years, industry has begun to mass-produce strong orthogonal nonwoven fabrics in which a large number of yarn groups are orthogonally crossed in the weft and warp directions using warp and warp laminating machines. The inventors of the present invention have already invented Japanese Patent Publication No. 40185/1983 and Japanese Patent Publication No. 38783/1983 as a laminating machine for producing these. The present invention fixes the arrangement of a large number of independent weft yarn groups using these warp and warp laminating machines, smoothes the warp and warp lamination process, and
It is also intended to improve the quality of the product by arranging the weft and warp threads in an orderly manner in the product. For this purpose, the inventors have
The present invention can be said to be an additional invention to the ``method for continuously fixing the arrangement of threads'' using the centrifugal spinning method of No. 9067. The method using the centrifugal spinning method of the previous invention is a method in which adhesive filaments are spun from inside the cylinder of a yarn group running in a cylindrical shape using a rotating nozzle similar to the cotton candy method, and the adhesive filament is spun with respect to the running direction of the yarn group. Ideally arranged in an orderly manner in the horizontal direction, adhesive filament fibers can be applied evenly in basis weight within a plane,
It has various features such as the ability to increase line speeds to as high as 100 m/min. However, since it is necessary to return the yarn group to a flat shape rather than a cylindrical shape, a larger three-dimensional space is required, which increases the cost of the apparatus. It is also difficult to apply it intermittently. Therefore, there has been a strong need for a method that can be applied on a flat surface using a simple device and that can be applied intermittently.

The importance of intermittent application is that if the adhesive fibers applied here become a nuisance in the final product, for example, if the yarn groups to be laminated in the warp or warp already have adhesive ability and the purpose is to fix the arrangement of the weft yarn groups, If the yarn groups are laminated in an orderly manner, the warp and warp yarn groups can be bonded in a subsequent process without applying an adhesive. Another example is when the yarn itself does not have adhesive ability, but the adhesive filament applied to fix the yarn arrangement is not suitable for the final product in terms of heat resistance, chemical resistance, etc. After lamination, the weft and weft threads are bonded and fixed using an adhesive suitable for the purpose, such as an emulsion adhesive. In such a case, as will be explained in detail later, the arrangement of the weft threads supplied by the warp/warp stacking machine should be fixed only in the vicinity where the weft threads are cut, and the adhesive material used to fix the arrangement should be fixed. This is the end of both ears of the product after laminating the warp and warp, and there has been a strong need for a method that allows that part to be trimmed so that it does not remain in the final product. These problems could not be solved by conventional techniques.

c. Means for Solving the Problems In order to solve the above problems, the inventors of the present invention continued their intensive research, and found that in the process of a large number of threads being arranged at regular intervals and running in a plane, The above problem can be solved by scattering a polymer liquid with high strength and spinnability using air, allowing it to arrive at the yarn group, adhering it, coagulating the adhesive filament, and fixing the arrangement of the yarn group with the coagulated filament. I found out. Furthermore, in a method for arranging and fixing weft yarn groups in the manufacture of non-woven fabrics, in which a large number of yarn groups are arranged perpendicular to the warp and warp, and the weft and warp yarn groups are adhesively fixed, in the process of running a large number of yarns arranged at regular intervals, A polymer liquid with high performance and spinnability is discharged in a linear manner, the linear polymer liquid is scattered with air, reaches the yarn group and adheres, the adhesive filament is solidified, and the adhesive filament arranges the yarn group. is fixed to form a weft web, and separately, a large number of threads are warped to intersect with this to create a running warp web, and the weft web is cut into lengths approximately corresponding to the warp width to form warp webs. It has also become possible to produce a weft/warp orthogonal nonwoven fabric by laminating and then adhering warp/warp webs.

As a result of experiments, it has been found that one of the methods most suitable for the purpose is to use a hot melt adhesive as the polymer liquid. It is already known in the hot melt adhesive industry to scatter hot melt adhesive into filaments with air and adhere it to an object, and devices for this purpose are commercially available, and are applied to diapers and cardboard. Spraying intermittently has already been done. The present invention has discovered that these hot melt spray systems can be applied to fixing the arrangement of a large number of thread groups, and furthermore, by using this fixed arrangement of a large number of thread groups as a weft thread group of a warp and warp stacking machine,
I found it to be very effective. Hot-melt adhesive melt is most suitable because it has good adhesive properties and good workability, but polymers that are not called hot-melt adhesives can also be used as long as they have threadability and have some degree of adhesive properties. I can do it.

Various methods can be used to spray the polymer melt into a filament. One example is the method used in the hot melt adhesive industry, which involves spraying several air holes around the spinneret. There is a method in which the spun filament-like melt is dispersed with air. The present invention utilizes this method to fix the filament arrangement. Furthermore, by colliding air so that the main component of the ejected and scattered filaments is in the direction perpendicular to the running direction (horizontal direction) of the running yarn group, and adjusting the scattering angle, a small amount of bonded filament can be used. You can effectively fix the array. This means that fewer spray guns are required, which reduces equipment costs and makes it easier to adjust the guns during operation. Since the air is heated air, the filament scatters more uniformly and the distance it scatters becomes wider. If the air temperature is lower than the melting point of the adhesive polymer, the polymer liquid will have a high viscosity, and the draft will not be able to thin the filament sufficiently, and the width of the scattered filament will be non-uniform. The distribution of filaments also becomes uneven. As a method for scattering filaments, if a method is used to manufacture random nonwoven fabrics, the line is running at high speed, so the array of scattered filaments will have many components aligned in the line direction (vertical direction), and the The number of filaments connecting the threads is small, and the method for fixing the thread arrangement is
It's not efficient.

If the raw material yarn of the product to be laminated has already been coated with an adhesive, or if a later adhesive such as an emulsion adhesive would result in a product that is more suitable for the purpose and hot melt adhesives are a hindrance. This can be achieved by using the method of the present invention as a means of fixing only the arrangement of the threads and preventing the sprayed hot melt from entering the product.
In other words, when using a warp/warp stacking machine to cut a group of running weft yarns into lengths that roughly correspond to the warp width and stack them on the warp web, the jet is sprayed only onto the first part and the last end of the cut weft web. By attaching the attached adhesive filament, the arrangement of each thread is maintained without being disturbed. In this way, the web is laminated in an orderly manner, laminated with warp and warp, and bonded using the adhesive ability of the raw material yarn by heat treatment, etc., or by applying adhesive such as emulsion bonding as necessary, to form both ends of the product. By trimming the hot melt adhering to the edges, the desired product can be manufactured.

Yarns with a fixed arrangement used in the present invention include ordinary flat yarns and monofilaments such as polyolefin, polyamide, and polyester, multifilaments and spun yarns of polypropylene, polyester, nylon, vinylon, and acrylic fibers, as well as glass yarns. Inorganic fibers such as yarns, carbon fiber multifilaments, and rovings can also be used. The intermittent spraying method of the present invention becomes effective when the yarns have the ability to adhere to themselves after they are orthogonally crossed. For example, when there is an LDPE layer on the surface of HDPE flat yarn, or when spun yarn such as polypropylene or polyester is blended with adhesive fabric.

The sprayed polymer used in the present invention can be EVA-based, polyamide-based, which is used as a hot melt adhesive, as long as it has spinnability and adhesive ability.
There are polyester types, etc., which are selected as appropriate depending on the use and purpose of the product. In addition to hot melt adhesives, wax alone, polymer units such as polyolefin, polyester, polyamide, etc., or materials based on these can also be used as long as they can be bonded to the yarns whose arrangement is to be fixed.

d Explanation with drawings The method of the present invention will be explained with reference to the drawings.

Fig. 1 is a process diagram showing an example of the present invention, in which 1 is a group of running threads, and polymer melt 3 discharged from spray guns 2a, 2b, ... is scattered in the form of filaments by air (not shown). A filament web 4 is formed in which the filaments are mainly attached and coagulated so as to be arranged horizontally with respect to the traveling yarn group. The guns 2a, 2b, . . . are arranged in two or more rows as shown in FIG. 1 to eliminate mutual interference of air between them.
The position of this gun is movable from side to side, so that the lap distance of the horizontally arranged filament webs that are sprayed can be mutually adjusted. The scattered filament web 4 is
At that stage, it is not necessarily necessary to firmly adhere to the thread group, and it may be adhered by heating or the like in a later process.

FIG. 2 shows an example of a spray gun 2a that scatters polymer. The spinneret 5 can be opened and closed by a needle 6 according to a signal as necessary. Spinneret 5
There are a plurality of air holes 8a, 8b around the inside that serve to twist the discharged filament 7.
(Not all shown in the diagram to avoid complexity), and air holes 9a and 9b on the outside that serve to scatter the filament (also not all shown)
There is. The air from the outer air holes 9a and 9b collides, and the filaments scattered thereby spread in a direction perpendicular to the plane of the paper, and spread in a direction perpendicular to the traveling direction of the yarn group 10 running downward.

FIG. 3 shows an example of warp and warp lamination using a weft and warp laminating machine, where a horizontal web 11a conveyed from the weft direction has portions to which adhesive filaments 13 are applied at intervals corresponding to the width of the vertical web 12.
The center part of the bonded filament 13 is cut with a rod-shaped heat cutter 14, and the filaments 13 are sequentially stacked in a manner perpendicular to the vertical web 12. Vertical web 12
The horizontal webs 11b, 11c, . . . are laminated so that the number of laps is as small as possible. If the horizontal yarn cannot be cut with a heat cutter, such as glass yarn, it is cut with a razor-like cutting edge.

e Examples Example 1 HDPE stretched tape (width 2.5 mm, 500 denier, the surface of the tape is coated with LDPE) is 3 mm
400 trains are arranged on a pitch approximately 1,200 width wide and run at a speed of 40m/min. From above, LDPE (MI, a 1:1 mixture of 100 and 2000) was sprayed into filaments with hot air using four spray guns as shown in Figure 2. The resin temperature was 210°C and the hot air temperature was 230°C. When the hot air temperature was lower than 110°C, the dispersion became extremely uneven and the spray width became unstable.
The filaments that were blown away by the 230°C air were arranged almost horizontally. Spraying was carried out intermittently every 1200 mm of the running length of the stretched tape as shown in Figure 3, and the width of the filament coming out of one spray gun was 320 mm and 50 mm in the line direction. The filament sprayed from each gun is
They are wrapped around each other by 10 to 20 mm. The filaments that protrude from the width of the 1200 mm running stretched tape group are received by a hot plate heated to 180°C, melted, and guided out of the system. Converting the amount of filament deposited on the tape per square meter:
It was 12 grams. This running tape group is guided as a weft web to a warp and warp laminating machine, and as shown in Fig. 3, the part where the filament is attached is cut with a heat cutter, and a weft and warp web is placed on the warp web using the same tape group as the weft. They were laminated and weft-welded in a heat cylinder at 115°C, and the parts of both ends where the LDPE filaments were attached were trimmed to make a stretched tape weft-width orthogonal nonwoven fabric.

Example 2 Polyethylene terephthalate (hereinafter abbreviated as
PET) stretched tape (width 3mm, denier
800) at 5mm pitch, 30m/1100mm width
Three spray guns are used to spray PET-based hot melt (trade name: Hardec A1200, melting point: 141°C, manufactured by Asahi Kasei Corporation) from above the group of stretched tapes running at 250°C with hot air at 250°C so that the filaments are lined up horizontally. . The scattering width of the filament from one gun is 350 mm, and the filament width is 20 to 30 mm and is wrapped around each other. The amount of filament injected was 5 grams per square meter, and this time it was sprayed all over the area instead of intermittently. This was guided as a weft web to a warp and warp laminating machine, where it was laminated with warp PET stretched tape groups and bonded on a heat cylinder at 170°C to form a PET stretched tape orthogonal nonwoven fabric. In the finished product, the weft and weft tapes are arranged in an orderly manner, and despite the small amount of glue, the weft and weft adhere well.

When the temperature of the hot air was lowered to 140°C or less, the spray width decreased and the uneven distribution within the width became noticeable.

f Effects of the invention Compared to the conventional technology, the device becomes cheaper and more compact. Since it can be sprayed intermittently, glue can be applied only to the heat-cut portion of the weft web that is heat-cut in the weft and weft laminating machine, making it possible to apply emulsion and products without hot melt adhesive, which are impossible with conventional methods.

[Brief explanation of drawings]

FIG. 1 shows an example of a method of scattering filaments onto a group of yarns to fix the arrangement among the yarns. FIG. 2 shows an example of a spray gun used in the present invention. FIG. 3 illustrates a method for orthogonally laminating the adhesive filament portions which are intermittently sprayed onto the weft web using a weft and weft laminating machine. Explanation of the main symbols: 1 is a group of running threads. 2a,
2b... is a spray gun. 5 is the spinneret of the spray gun. 6 is a needle that can block the spinneret. 8
a, 8b, 9a, 9b are air holes. 11a, 11
b... is a weft web in which threads are arranged. 12 is a vertical web with arranged threads. 13 is the part to which adhesive filaments arranged horizontally are attached. 14 is Heat Katsuta.

Claims (1)

[Claims] 1. In the process in which a large number of threads are arranged at regular intervals and run, a polymer liquid with adhesive ability and spinnability is dispersed with air, arrives at the thread group in the form of a filament, and is coagulated. A method for fixing the arrangement of a large number of thread groups, characterized in that the arrangement of the thread groups is fixed using the filament. 2. In the method of arranging and fixing weft yarn groups in the manufacturing of non-woven fabrics, in which a large number of yarn groups are glued and fixed perpendicular to the weft and warp directions, in the process of running a large number of yarns arranged at regular intervals, the threads have adhesive ability and are The polymer liquid is dispersed in filament form using air.
The filaments are applied to the yarn group, coagulated and bonded, and the filament fixes the arrangement of the yarn group to form a weft web. Separately, a warp web that runs intersecting with this web is made into a warp web with lengths approximately corresponding to the warp width. A method for arranging and fixing a large number of yarn groups, characterized by cutting a weft web, laminating it orthogonally with a warp web, and bonding the warp and warp webs to produce a warp orthogonal nonwoven fabric. 3. The method of arranging and fixing a multi-strand group according to claim 1, wherein the air to be scattered is air heated to a temperature higher than the melting point of the polymer which is the main component of the polymer liquid. 4. A method according to claims 1 and 2, characterized in that air is collided with and dispersed so that the solidified and bonded filaments are arranged in a direction whose main component is perpendicular to the running direction of the running yarn group. How to fix the arrangement of thread groups. 5 In claim 2, when the running weft yarn group is cut into lengths approximately corresponding to the warp width and laminated with the warp web, the weft yarns solidify only at the first part and the last end of the cut weft web. A method for fixing the arrangement of a multi-thread group, characterized in that a glued filament is attached and the arrangement of the weft group is fixed at that part.