JPH02112457A - Nonwoven fabric having open hole pattern and production thereof - Google Patents

Abstract

PURPOSE:To obtain the subject nonwoven fabric having a checkered pattern or a polka dot pattern and excellent appearance, touch and feeling and useful as gauze, etc., by placing a web on a porous supporting net and applying water stream to the web through a specific patterned mask from above. CONSTITUTION:A web is placed on a porous supporting net and a water stream is applied to the web over the whole width through a patterned masking plate from above. The making plate is composed of a laminate of the 1st net corresponding to 5-30 mesh and the 2nd net having a mesh opening corresponding to (19-11)/10 or 10/(11-19) of that of the 1st net. The objective nonwoven fabric has openings of about 1.2-1.5mm in diameter arranged nearly in the form of a lattice with intervals of about 1.2-3 times the diameter wherein said openings are encircled with non-opened part and nearly regularly arranged in such a manner as to form a checkered pattern or a polka dot pattern.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a perforated nonwoven fabric and a method for producing the same, and more particularly to a perforated nonwoven fabric with a special perforation pattern and a method for producing the same. It is.

[Prior art] An endless belt or cylindrical metal processed into ■4 or perforated (a web is placed on top of the fabric and a water stream is applied to it while moving, and the water stream loosens the fibers that make up the web. A method for manufacturing a perforated nonwoven fabric in which the fibers are moved and forced into the holes for gold, and the fibers at the intersections of the whole fabric or the unperforated portions are excluded to form the perforations is known from Japanese Patent Publication No. 36-7274. .

However, with this method, only a fine perforated pattern can be obtained over the entire surface of the nonwoven fabric, and attempts have been made to provide even more complex lace patterns.

For example, it is known from Japanese Patent Publication No. 18069/1983 that the perforations in the temporary (supporting) part on which the web is to be deposited have a special pattern, with holes having a lace-like pattern. It is being

It has also been proposed in Japanese Patent Publication No. 10666/1983 to combine a net-like material with the perforated portion of the support plate to form a composite pattern of large lace-like openings and small openings in the net-like material.

Also, regarding the spacing of the water nozzles that generate rod-shaped water streams,
If the spacing of the perforations on the plate on which the web is to be deposited is different, the pattern of perforations is applied only to the area where the nozzle and the perforation coincide, and the area where the nozzle does not correspond to the perforation is treated as a non-perforated area without a pattern. A method of imparting a striped pattern to a web in the longitudinal direction is disclosed in JP-A-61-6355.

It is also known from Japanese Patent Publication No. 10666/1983 to limit the openings by blocking the water flow hitting the web with a shielding plate perforated in a special pattern, and to shape and pattern the openings. It is being

[Problems to be Solved by the Invention] The method disclosed in Japanese Patent Application Laid-open No. 61-6355 only provides a monotonous set of wires in the longitudinal direction, and in order to change the pattern, it is necessary to install nozzles and supports to receive the web. It is necessary to replace the plates each time, which requires a lot of labor in industrial implementation, and there is also the problem that production is interrupted during replacement, resulting in the loss of one worker.

Also, Special Publication No. 47-18069 and Special Publication No. 1974-1.
0666η = The method of applying a pattern on a support plate with a pattern, such as the publication, requires replacing the support plate in order to change the perforation pattern. In addition to the problems, in order to maintain the strength and shape of the support plate, the openings in the support plate should be discontinuous and independent, or the width of the non-opening portion should be less than a certain width. There are restrictions such as the need to do so, and there are limits to the perforated patterns that can be obtained.

Similarly, in the method disclosed in Japanese Patent Publication No. 54-10666, etc., in which water flow is blocked by a shield having specific openings, the problem of replacing the support plate described above is alleviated, but there are limits to the perforation pattern of nonwoven fabric. There remain issues regarding this.

In any of these methods, the boundary between the perforated part and the non-perforated part becomes clear, and as a nonwoven fabric that should be used as a substitute for textiles, it looks bad, has a bad feel and texture, and is prone to deformation. There were problems such as stress being concentrated in this area.

Another problem with these methods is that whether the supporting plate is provided with an opening pattern or the second pattern is provided, the opening shape of the opening plate is In order to maintain the shape, it is necessary to make it an independent open IT+, and from the viewpoint of machining accuracy and strength of the molded plate, making it minute is a rotation, so the opening has to be large, and the lace Only nonwoven fabrics with large openings were obtained.

These lace-like large-diameter openings are used in household products such as wet wipers and industrial wipers (non-woven fabrics).
ηThere are few calculations [] that are effective in wiping away stains, there is a lack of ability to remove dirt, and because the opening is large, objects pass through the opening and stain hands, etc. It has been desired to provide a nonwoven fabric with a novel structure that has an excellent ability to wipe away dirt and does not allow the dirt to pass through the nonwoven fabric and stain hands.

That is, the first object of the present invention is to have an appearance, feel, and feel that are good enough to be used as a substitute for textiles, as well as to have an excellent function of wiping away dirt, and to allow the dirt to pass through the nonwoven fabric and be removed from the hands. Our objective is to provide a nonwoven fabric with a novel structure that combines the characteristics of 'IQ Zukotona' and a variety of patterns that are preferred by consumers.

A second object of the present invention is to provide a means for easily changing the perforation pattern without replacing supporting plates, patterned perforation shielding plates, etc., which is a major problem in industrial production. It is to be.

[Means for Solving the Problems] A first object of the present invention is to provide a nonwoven fabric having a perforated portion and a non-perforated portion, the perforated portion having a diameter ranging from 0.2 mm to 1.5 mm. The holes are opened in a substantially grid shape at intervals of about 1.2 to 3 times the diameter, and the holes are surrounded by non-open holes to form a checkered or polka dot shape. This is achieved by a non-woven fabric having a pattern of apertures, which are characterized by being arranged substantially regularly to form a pattern.

In addition, the nonwoven fabric of the present invention can be produced by placing the web on a porous support net and applying a water stream over the entire width of the web through a patterned shielding plate from above the web to produce a nonwoven fabric with holes. In doing so, as the shielding plate, a first ANI-like material equivalent to 5 to 30 meshes and a first cotton-like material 19/10 to 11/
The second Old Testament of the present invention is also achieved by this method.

The mechanism for producing the perforated nonwoven fabric with the special pattern of the present invention is to deposit the web on a porous cotton or equivalent perforated board (hereinafter collectively referred to as a support net), and From above, a water stream is applied over the entire width of the web through a shielding net consisting of a combination of two cotton-like materials having a special relationship, which is a feature of the present invention, and the opening of the two mesh-like materials is carried out. Only the overlapped interference points serve as passage points for the water flow, and the passing water flow displaces the fibers constituting the web on the support net around them, forming open pore points in the web. Therefore, the obstruction if 1F4 is An aperture pattern corresponding to the interference pattern of the aperture points of the two meshes to be formed is formed.

Furthermore, if the support is 3 or 40 mesh, preferably 30 mesh or more, of the water flow hitting the web,
Only the part of the support net that hits the wire A-- or the non-perforated part of the perforated plate will force the fibers that make up the web into the AM opening between the wires and form an opening, so the support net will block the M In the case of a mensch different from any of the flocculent materials in ljl, triple interference occurs.

To explain the opening +L which is a feature of the present invention with reference to the drawings, as shown in Fig. 1, the support net is 70 mm, the first shielding net is 20 mm, and the second shielding net is 1214, 16 mm.
, 18 meshes, according to the above mechanism, the interference point (opening) model (hair) was simulated by a personal combination.

The lattice striped pattern obtained by the method of the present invention is formed by a pattern of openings in which the holes are arranged in a substantially grid pattern corresponding to the mesh, that is, at the intersections of mutually orthogonal rows, as shown in the example in FIG. The aperture part 1 is entirely surrounded by the non-aperture part 2, forming a checkered pattern or a polka dot pattern.

Figure 2 shows simulation results for several combinations of shielding nets when the support net is 20 or 30 meshes, and of the interference points in Figure 1, only the points that overlap with the wire of support point F[ It appears that there was an open hole, and that there was further interference with the support N.

Furthermore, as a special application example of the present invention, when shielding nets are combined with mutually inclined meshes, there is a phenomenon in which the interference pattern is tilted more than the inclination of the meshes. The simulation results of interference patterns are shown when the meshes of the shielding meshes are tilted by 3.5 degrees and 7.9 degrees using a combination of 20 meshes and 22 meshes.

The size of the opening is about 1.5 plates or less, preferably 1 plate.
．． It needs to be 0 mm or less; if it is larger than this, dirt will pass through the nonwoven fabric and stain hands when used as a wiper, similar to the conventional nonwoven fabric with a lace-like opening pattern.

On the other hand, when the aperture is less than about 0.2 + nm, the toughness of the aperture becomes poor, which is not preferable.

The shape of the aperture does not need to be a perfect circle or square, but may be an ellipse or a rectangle, and in these cases, the size of the aperture is expressed by the major axis or the length of the long side.

As is clear from the above-mentioned opening mechanism, the size of the openings obtained here is approximately determined by the size of the mesh of the shielding key 14 used.
0 mesh, preferably 8 to 25 mesh should be chosen.

Furthermore, the spacing between the openings should be selected within a range of approximately 1.2 to 3 times the diameter of the openings; anything outside this range is not preferred as it may impair the strength of the nonwoven fabric.

It is also permissible that the intervals between the holes in the group of holes arranged in a grid forming the hole section are different in each orthogonal row.

Furthermore, when the method of the present invention is actually implemented apart from computer simulation, it is naturally expected that the degree of interference will change, and depending on the magnitude of the action of the water flow, it will be possible to create patterns ranging from checkered patterns to polka dots and even special patterns. In some cases, the pattern may even be transformed into a checkerboard pattern, illustrating various embodiments of the present invention.

In principle, an interference pattern can be obtained even if the mesh ratio of the net-like material constituting the shielding net is larger or smaller than the above range, but in reality, an interference pattern that is clearly recognized by the naked eye cannot be obtained. unattractive and undesirable.

As shown in FIG. 4, the hole opening process of the present invention is carried out by depositing the web 3 on a support net 4, and placing a first shielding net 6a and a second shielding net 6b thereon. , it is preferable that they be treated by being exposed to a water stream jetted from the nozzle 5 while moving at a substantially constant speed.

Furthermore, in the case where the shielding nets are installed as meshes installed at an angle to each other, which is an applied example of the present invention, a specific method of tilting and overlapping the meshes of the shielding net is as shown in FIG. An endless net made by cutting the mesh at an angle and connecting it endlessly may be used as the shielding net 6a and run parallel to another shielding net sb running parallel to the support net, or as shown in FIG. In this method, an endless net cut in parallel is used as the shielding net m6a, and the running direction thereof is inclined at a predetermined angle with respect to another shielding net 6b running parallel to the support N2, and the net is installed and run. However, the latter is a more preferable embodiment in that the inclination of the checkered pattern of the nonwoven fabric can be easily changed.

Of course, the same effect can be obtained by fixing the support net/web/shield Mho and moving the water flow, which is convenient for making small pieces in a laboratory.

Although the shielding nets may be stacked in contact with each other, it is also a preferable embodiment to install them with some spacing between them. In this case, by moving the shielding nets at different speeds, the interference interval can be easily changed.

Furthermore, if the hole opening process is performed while varying the speed of the shielding nets, various patterns such as a pattern in which the interference interval changes continuously can be easily obtained.

? ! The shielding cotton may be stacked in contact with the web, but it is also a preferred embodiment to install them with some spacing, and in this case, one set of shielding W is moved at a speed different from that of the support net and the web. This makes it possible to easily change the interference interval. Furthermore, by performing the opening process while varying the speed of the shielding net, various patterns such as a pattern in which the interval between each step changes continuously can be easily obtained.

There are no particular restrictions on the material of both the support net and the shield net, and metal ropes such as stainless steel, phosphor bronze, and brass, polyamide, polyester,
Nl2 made of monofilaments or twisted multifilaments of synthetic polymers such as polyvinylidene chloride, nets made of glass fibers or aramid fibers coated with fluororesin, etc. are all suitable.

The weaving structure of these nets is also not particularly limited;
Usually, a plain weave structure is used, but diagonal weave structures and other structures are also preferably used in view of diversifying the hole patterns. Furthermore, it is permissible that the structures of the support cotton and Z+'B km are different as long as the above-mentioned silky mesh relationship is within the scope of the present invention, and in creating a new interference pattern, Interested.

Even if the support net has a woven structure, it may be a welded entire structure in which wires are simply crossed and overlapped and welded at the intersections, or a plate-like structure in which holes corresponding to the openings of the mesh are perforated by a method such as punching a film or sheet. It may be a product or a sheet-like product.

The shielding net does not necessarily have to have a woven structure; it can also be a welded Nr4 material made by simply crossing and overlapping wires and welding the intersection points, or a plate-like material made by perforating the mesh portions by a method such as punching. Also used in the same way.

The water flow used in the treatment of the present invention may be any water flow with the energy necessary to remove the web-constituting fibers on the support net from the wires constituting the net and create pores, and is usually 20 kg/water flow. A water stream ejected from a nozzle at a pressure of approximately c-aG is used. There are no particular restrictions on the shape of the nozzle, such as a nozzle that spreads the ejected water flow in a fan shape or a cone shape, a slit that creates a film-like water flow,
Any nozzle or the like that forms a rod-shaped flow can be arbitrarily selected and used depending on the fiber material of the web to be treated, the thickness of the web, etc. However, when water treatment is carried out using a plurality of nozzles, the spacing between the respective nozzles must be carefully selected so that the water flow hits almost the entire width of the shielding net, as understood from feature i of the method of the present invention. Approximately the gap between the water streams from each nozzle should be less than the spacing between the wires of the screen. Furthermore, the water flow treatment may be carried out in multiple stages, and as long as the positions of the shielding net and the supporting net are kept in place during this period, a clearer interference pattern can be obtained, which is recommended.

If necessary, the water flow may be suctioned from the back side of the support net and forcibly removed.

The nonwoven fabric that has been open-ripened with a water stream is further treated, if necessary, with the fibers being entangled with each other using a high-pressure rod-shaped water stream.
After being subjected to treatments such as adhesive treatment, it is dried and rolled up for use, but there are no particular limitations on these steps, and any means and conditions may be selected. It's fine.

The method for producing a web for producing the nonwoven fabric of the present invention is not particularly limited, and any method may be used to produce the web.

Namely, there are methods of suspending short fibers in water and making paper, methods of dispersing short fibers with an air stream and collecting them in knitting-1, methods of forming staple fibers into a web using cards, and methods of forming webs by directly connecting them to spinning. The so-called spunbond method is used to form
etc.

The fibers that form the web are not particularly limited, and include synthetic fibers such as polyester, polyamide, polypropylene, and acrylonitrile polymers, recycled fibers such as rayon, guplar (buttons to ammonia-processed rayon), and natural cotton fabrics. Any type of fiber may be selected arbitrarily, and it is also permissible to use two or more of them in combination, but from the viewpoint of functionality as a wiper, fibers consisting of or containing cellulose fibers are preferred. is often preferred.

These fibers may be short fibers, continuous fibers, or a mixture thereof.

(Function of the invention) According to the nonwoven fabric having apertures with a special pattern of the present invention, as is clear from the manufacturing method of the present invention, the apertured portion and the non-perforated portion forming a lattice pattern are formed by two sheets. Because it is obtained as an interference pattern between the shields N1jl and, in some cases, with the support network,
Unlike the perforated non-woven fabric made of conventional patterned Mu plates, the perforated part is smoothly and continuously connected to the non-perforated part without having a clear boundary, so that stress is reduced when the non-woven fabric is deformed. There is no concentration and therefore no loss of strength. or,
The fact that the boundary between the apertured part and the non-perforated part is not clear does not give the sense of discomfort of the boundary L1 to the touch, and also gives a natural and beautiful appearance to the mouth.

In the perforated non-woven fabric 4 of the present invention, the perforated portion has the desired effect of fibers, so it gives a sense of volume, and the intertwining of the fibers creates strength as a non-woven fabric. It also provides water permeability and breathability to the nonwoven pores.

On the other hand, the non-perforated part has good wipeability, water retention, and covering 1 (
L etc. are given to the nonwoven fabric, and these patterns and ratios are appropriately selected1.
By adjusting the length, it is possible to provide nonwoven fabrics suitable for various uses.

According to another embodiment of the method of the present invention, each time the two shielding nets are placed around each other, the checkered pattern due to the interference is changed to 1):1:1, -. A unique slanted pattern can be created, and a compound i:fe perforation pattern can be easily created by simply combining 1J1 of perforated materials such as plain woven wire mesh and punched sheets, which are inexpensive and easily available. In addition, changing the board type, which was a problem with the prior art, becomes easy.

[Example of ability]

EXAMPLES The detailed description of the present invention will be described below with reference to Examples, but it goes without saying that the present invention is not limited thereto.

The refined linter was dissolved in 4 liquids (copper ammonia complex water) and extruded through a number of holes into a rectangular funnel-shaped coagulation bath according to the method disclosed in Japanese Patent Publication No. 52-6381. Together with the water for coagulation supplied to the coagulation bath, it flows out through a slit from below the coagulation bath, flows down together with the coagulation water in a film, and is collected on a net conveyor made of polyester monofilament. A cuprarayon spunbond web was produced by washing with sulfuric acid and further washing with water.

This web was subjected to the perforation treatment of the present invention using the apparatus shown in FIG. That is, the web 3 has a wire diameter of 0.193
Replace it on an endless gold wire (supporting net) 4 made of plain-woven brass wire of mm, length 70 mm and width 49 mm, and its 15 cm 1
Water of 30 kg/CIA C was spouted from the nozzle 5 located at , and was applied to the web 3 as a fan-shaped water stream with an angle of 20°.

Between the nozzle 5 for water flow generation and the web 3, the wire diameter is 0.
．． The first shielding net 6a is an endless net with a plain weave structure of 75 mm polyester monofilament and has 16 meshes in the vertical direction and 15 meshes in the horizontal direction.The second shielding surface 6b is an endless net with a wire diameter of 0.457 mm. A 20-mesh endless Kanagawa wire made of a plain weave structure was installed and run so as to run at an angle of 7 degrees from the running direction of the first shielding net and support net.

A suction box 7 was provided on the back side of the support net to suck up the water flow that penetrated the web.

Gubra spunbond web consists of two pieces of 3!2 Sou XR
The water flow that passes through the point where the steel grains of I overlap forms holes in the web.

In this state, the support net 1 is guided into the hot air dryer 8,
After drying at 120°C, it was moistened and then wound up as a roll 9.

The obtained nonwoven fabric with aperture pattern has 1 aperture of 0.3 mm to 0.7 man as shown in the photograph No. 7V.
．． The non-woven fabric is arranged in a grid pattern at intervals of 6 m1 to 1.7 mha, and the perforations are arranged in a polka dot pattern between the non-perforated parts at an angle of approximately 45 degrees with respect to the longitudinal direction of the nonwoven fabric. Ta.

When this perforated nonwoven fabric is used as a wet tissue, it has a soft texture compared to the comparative example shown below.
The thickness was improved.

Comparison [Example 1 except that the shielding net was not installed, a cuprus spunbond perforated nonwoven fabric was produced in exactly the same manner.

The pattern of the resulting perforated nonwoven fabric is a simple pattern in which all the intersections of the first layer of the support net are perforated, as shown in Figure 8, and when used as a wet tissue, it feels hard and thick. There was little anger.

In Example 1, the second shielding net had a wire diameter of 0.48 mm.
Plain weave of polyester monofilament 1+I'l
A nonwoven fabric was produced in the same manner, except that the mesh was changed to an endless mesh with 17 meshes in the sound direction and 15 meshes in the transverse direction, and a perforated nonwoven fabric as shown in FIG.

In Soukoho Example 1, the wire diameter of the shielding ul Vkl was 0.48 m.
m polyester monofilament 1-〇 plain weave structure,
The length is 17 mesh, the horizontal direction is 15 mesh, and there is only an endless shoe rope, and the support net has a wire diameter of 0.・Changing to a 20-mesh endless wire mesh made of a plain weave structure of 157-hole brass wire, instead of the perforation mechanism of the present invention, as a silk combination that generates an interference pattern with only the shielding mesh and the support mesh, 1.1 The fabric was molded. The obtained nonwoven fabric exhibited a checkered pattern as shown in FIG. Ori,
It can be seen that the perforated nonwoven fabric of the present invention has a completely 5"4 perforated pattern.

〔Effect of the invention〕

According to the method of the present invention, the perforation pattern of the nonwoven fabric can be easily changed, and the perforation chair 1η can also be used in patterns that have not been practiced in the past, such as a lattice pattern, a polka dot pattern, and a checkered pattern. It is a product that responds to the diverse demands of consumers.

In the perforated nonwoven fabric of the present invention, the perforated part has a collection of fibers, so it gives volume, and the fibers are intertwined with each other, so it is effective in expressing the strength as a nonwoven fabric. 1) Add water permeability and breathability to nonwoven fabrics.

On the other hand, the non-perforated portion imparts wiping properties, water retention properties, covering properties, etc. to the nonwoven fabric, and by appropriately selecting these patterns and ratios, it is possible to provide a cost-effective fabric suitable for various uses.

Applications of the nonwoven fabric of the present invention include materials for the medical field such as gauze and phosbicle towels, industrial wipers,
Examples include various types of wipers such as towels, dish towels, and wet napkins, and power cloths such as table cloths and sheet covers.

[Brief explanation of the drawing]

FIG. 1 explains the perforation pattern of the present invention, in which 1 is a perforated part and 2 is a non-perforated part. FIGS. 2 and 3 show interference patterns of the present invention. FIG. 4 shows the hole processing equipment used for carrying out the present invention, 3 is a web, 4 is a support net made of endless wire mesh, 51 is a nozzle, 6 is a shielding screen, 7 is a suction box, 8 is a hot air dryer. FIG. 5 and FIG. 6 show embodiments of the shielding net used in manufacturing the nonwoven fabric of the present invention. FIG. 7 and FIG. 9 are photographs of the perforated nonwoven fabric of the present invention, and FIGS. 8 and 10 are photographs of the perforated nonwoven fabric of a comparative example and a reference example.

Claims (2)

[Claims] 1. A nonwoven fabric having a perforated part and a non-perforated part, the perforated part having a diameter of 0.2 mol to 1.5 mm,
Holes are formed in a substantially grid shape at intervals of about 1.2 to 3 times the diameter, and the openings are surrounded by non-opening areas to form a checkered or polka dot pattern. A nonwoven fabric with a pattern of pores that are arranged almost regularly. 2. A web is deposited on a porous support net, and a water stream is applied from above the web over the entire width of the web through a patterned shielding plate to produce a nonwoven fabric with openings. A first mesh material equivalent to 5 to 30 mesh and 19/10 to 11/10 times or 10/1 of the first mesh material.
A method for producing a nonwoven fabric having an aperture pattern, characterized by using a layered second net-like material corresponding to a mesh of 1 to 10/19 times.