JP2813584B2 - Spunbonded nonwoven fabric and manufacturing apparatus therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a nonwoven fabric comprising two types of bicomponent filaments of type A and type B, wherein the content of bicomponent filaments of type A and type B along the vertical cross section of the nonwoven fabric is Different spunbond nonwovens.

[0002]

2. Description of the Related Art As a spunbonded nonwoven fabric, for example, Japanese Unexamined Patent Publication (Kokai) No. 61-43528 discloses a nonwoven fabric known as a bag material. The spunbond nonwoven is composed of two types of long, composite multicomponent filaments A and B. Type A filaments consist of polymer components (a1) and (a2). The polymer component (a2) has a melting point higher by 30 ° C. than the polymer component (a1). Type B filaments consist of polymer components (b1) and (b2). The polymer component (b1) has a melting point 20 ° C. higher than the polymer component (a1), and the polymer component (b2)
It has a melting point 30 ° C. higher than 1).

Further, this spunbonded nonwoven fabric has a four-layer structure in a vertical section. The difference between the individual layers is that the first layer has only filaments of type A, the second and third layers consist of filaments of type A and B, while the fourth layer which follows is of type A The point is that it is constituted only by the filament B. In the second layer, the content of the type A filament is higher, and in the third layer, the content of the type B filament is higher.

[0004] The difference in melting points on both surfaces of the spunbonded nonwoven fabric and the difference in melting points in the cross-section of the spunbonded nonwoven fabric resulting from this arrangement prevents delamination of individual layers.

[0005]

It is an object of the present invention to provide a spunbond nonwoven comprising a core / sheath bicomponent filament having a hard core and a jacket that melts at a lower temperature than the core. That is, the distribution of these bicomponent filaments in the vertical cross section of the spunbonded nonwoven fabric is different, and the interior is formed to be more flexible or harder than at least one of the outwardly facing individual surfaces. Is to provide such a spunbonded nonwoven fabric.
In this case, for example, after temperature treatment during coloring and steam treatment,
Alternatively, the difference in filament distribution should not be embodied in a layered structure with specific boundaries to prevent the risk of delamination of individual layers due to mechanical loads during molding and the like. . Therefore, a very gentle, fluid staging of the concentration of the bicomponent filaments in the direction of extension of the cross-section of the spunbond nonwoven, and thus of the bicomponent filament bonding or adhesion, must be obtained.

[0006] The invention further relates to an apparatus suitable for producing such a spunbonded nonwoven fabric. This device differs from the prior art, i.e., it requires a number of separate steps to form and bond the individual layers of spunbond nonwoven, each of which specially positions the spinning nozzle beam. Unlike the prior art, where it is necessary to do so, only one device with the spinning nozzle beam appropriately positioned is sufficient. In this case, the arrangement of the spinning nozzle beam can be the same as that in a usual apparatus for producing a monofilament.

[0007]

SUMMARY OF THE INVENTION The solution to the above problem is described in the independent claims relating to the object and the device respectively. Advantageous configurations for this are characterized by the dependent claims. That is, according to the present invention, type (a)
A non-woven fabric comprising a two-component filament of the same type and a two-component filament of the same type (b), wherein the two-component filament is made of an adhesive polymer material; A core material (1) made of polyethylene terephthalate, which melts at a higher temperature than the jacket material (2); and a jacket material (2a) of a type (a) filament and a jacket material (2) of a type (b) filament 2
The weight ratio 2a: 2b of b) is from 1: 3 to 1:10, and the weight ratio of the type (a) filament to the type (b) filament is from one surface along the vertical cross section of the spunbond nonwoven fabric. The filaments of type (b) differ so that they vary in the range of 15 to 70% by weight towards the other surface, and the weight ratio of the filaments of type (a) to the filaments of type (b) is A spunbonded nonwoven fabric is provided that changes in a vertical cross section of the nonwoven fabric without creating identifiable phase boundaries.

An apparatus for producing such a spunbonded nonwoven fabric also has 1 to 40 rectangular spinning nozzle plates (3) or circular spinning disks (4),
These spinning nozzle plates (3) or spinning disks (4) are provided with spinning holes (5, 6) and are arranged above a drafting device for the filaments to be discharged from the spinning holes (5, 6). Below the drafting device, there is provided a conveying device provided with a collecting belt (7) for a filament which can be moved linearly in the horizontal direction, and each of the spinning nozzle plate (3) and the spinning disk (4) is provided. Has a spinning hole (5) for discharging a bicomponent filament of type (a) from the melt, and a spinning hole (6) for discharging a bicomponent filament of type (b) from the melt. , 6) Collecting belt from the whole (7)
The order and arrangement of these spinning holes (5, 6) are selected such that the upward spinning corresponds to the density distribution of the bicomponent filaments in the vertical cross section of the spunbonded nonwoven fabric, and in the direction of movement of the collecting belt (7). The bicomponent filament mixture forming one surface of the spunbond nonwoven along is spun first and impinges on the collection belt (7), then the bicomponent filament mixture forming the inner region of the spunbond nonwoven is spun. Placed on the first bicomponent filament, and finally on the previous bicomponent filament mixture to which the bicomponent filament mixture forming the other surface of the spunbond nonwoven has been conveyed.

[0009]

DETAILED DESCRIPTION OF THE INVENTION Referring first to FIG. 1, there is shown an example of two type a and type b core / sheath bicomponent filaments used in accordance with the present invention. 1 is a core made of polyethylene terephthalate, 2
Is a jacket made of an adhesive component. Filaments having such a cross section and ejected from the melt by a nozzle are known per se and are not the subject of the present invention.
The three examples shown in FIG. 1 show possible arrangements of these components as a core / sheath, but are not limited to these.

Examples of adhesive components 2 include copolymers of terephthalic acid or dimethyl terephthalate, isophthalic acid, adipic acid, ethylene glycol, butanediol, and polybutylene terephthalates, polyamides, and homologous series from polyethylene to polybutylene. And a homopolymer such as polyolefin.

As already mentioned, the filament counts of the types a and b are the same, and the weight ratio 2a: 2b of the jacket component between these types ab according to the invention is 1: 3.
１ ： 1: 10.

The present invention consists of these two types a and b of core / sheath filaments, wherein the content of these bicomponent filaments varies from one surface to the other along the vertical cross section of the nonwoven. A spunbond nonwoven fabric. In the present invention, the content of type b is changed in the range of 15 to 70% by weight in the vertical cross section of the target spunbonded nonwoven fabric. The content of type a accordingly varies in the range from 85 to 30% by weight.

What is important in the present invention is that spunbonded nonwoven fabrics having different contents of the type a and type b bicomponent filaments can be produced from one surface to the other surface without showing a distinct phase boundary in cross section. The content changes smoothly. Accordingly, delamination as in the case of a spunbonded nonwoven fabric layer in which layers having different filament compositions are laminated is suitably prevented.

Accordingly, a wide variety of spunbonded nonwoven fabrics can be realized, in which case the weight per unit area can be produced as desired, for example, from 10 to 500 g / m ² .

The content of type a and type b can be varied depending on the desired application of the spunbond nonwoven. For example, if the content of the type b bicomponent filament is small, the corresponding portion of the spunbonded nonwoven fabric becomes more flexible and easily bent. On the other hand, in an extreme case where 70% by weight of this type b bicomponent filament is present, internal stability is obtained at a corresponding portion of the spunbonded nonwoven fabric. As a supporting means and a stabilizing means.
In the latter case, the relevant part of the spunbond nonwoven fabric is
There is also a blocking function that prevents leakage of fluid, which is important for filter applications. Such a blocking function is obtained by the envelope components joining the individual filaments intermingling with each other to form a barrier to the fluid.

In an advantageous variant of the invention,
The type b bicomponent filament content is increased on one surface of the spunbond nonwoven fabric relative to the other surface. Therefore, this one surface is hard and has hot-melt adhesiveness. The other surface has a lower bicomponent filament content of this type b and is therefore flexible, but has a lower hot melt adhesion.

The high filament content of type b and the hot-melt adhesion are another advantage of the construction of the spunbonded nonwoven fabric according to the invention, especially for spinning-related applications such as, for example, reinforcing padding. is important. The vertical cross section of such a spunbonded nonwoven fabric has a constant gradient in the content of bicomponent filaments of type a or b, and therefore a constant gradient of hardness from one surface to the other.

An alternative embodiment in which the surface of the spunbonded nonwoven is hardened with bicomponent filaments of type b in a proportion of 70% by weight can find use in the production of tufted carpets.

When a foamed layer is formed on such a tufted carpet, the gradient in the direction of the hard surface containing a large amount of the bicomponent filaments of the type b prevents the agent from penetrating from the soft surface side to the side fibers. Block. This gradient therefore also indirectly controls the tear resistance of the finished carpet.

On the other hand, a bulky, soft spunbonded surface promotes the formation of a suitable fluff, thus promoting the carpet fibers to stick to the spunbond nonwoven cross-section during tufting.

Further, the tufting needle can penetrate into the spunbonded nonwoven fabric from the hard side, and the fibers detached from the spunbonded nonwoven fabric do not hinder the formation of tufts by being caught by the needle.

A fourth advantage applied to the tufted carpet is that the carpet can be processed with a reduced fiber (weight on the fuzz side) and a reduced length (height on the fuzz side), In addition, the present invention does not cause a change in the design of the surface (the design on the fuzz side) due to the fibers that have come off from the spunbonded nonwoven fabric composite.

Another advantageous embodiment of the invention relates to a spunbond nonwoven fabric having two softer surfaces, wherein the content of bicomponent filaments of type b is lower in the outer region than in the inner region. The inner region has a higher percentage of type b bicomponent filaments and is thus formed more rigid.

The present invention also includes a variant embodiment of a spunbond nonwoven fabric having a relatively high content of type b bicomponent filaments on the two outwardly facing surfaces, and thus having a hard base. . In this case, the inner region has a low filament content of type b and is very flexible.

In the two alternative embodiments just mentioned,
Even when the hardness of the outer surface is the same, in the former case, that is, when the bicomponent filament content of the type b is low in the outer region, the texture on both sides becomes a very good planar structure, and in the latter case, When the outer surface is hard and the inner central portion is soft, the air permeability is high, and it is possible to manufacture a planar structure having a large volume. Such a property is effective for an air filter that requires a load capacity and strength exclusively for the outer surface. In the production of this type of filter, there is an advantage that the fibers are not detached from the structure at the time of processing even though the material is flexible.

The present invention also relates to an apparatus for producing a spunbond nonwoven as described above. With reference to FIGS. 2 and 3, the device has from 1 to 40 rectangular spinning nozzle plates 3 or circular spinning disks 4.
The spinning nozzle plate 3 or the spinning disk 4 is arranged above a conventional drafting device (not shown) for drawing the filament leaving the spinning holes 5,6. The unwound filament falls onto a transport device provided below the draft device. The main component of the transport device is a collection belt 7 that can be moved linearly in the horizontal direction. The filament collides with the surface of the collection belt 7,
Processed into spunbond nonwoven.

The spinning hole 5 is used for discharging a core / sheath filament of type a, and the spinning hole 6 is used for discharging a core / sheath filament of type b. Both type a filaments and type b filaments consist of a melt.
Both spinning holes 5, 6 are provided in the spinning nozzle 3 or the spinning disk 4.

In this case, according to the present invention, the spinning holes 5, 6
Is selected as follows. That is, the order in which the filaments of the two types a and b collide with the collecting belt 7 to be moved is in a predetermined temporal order, and is a linear order with respect to the surface of the collecting belt 7, that is, the moving direction. Are chosen to be in a certain order along For this purpose, the device is used for the spinning plate 3 used.
Alternatively, the spinning of all the spinning holes 5, 6 of the spinning disk 4 with respect to the surface of the collecting belt 7 corresponds to the density distribution of the bicomponent filament mixture in the vertical cross section of the spunbond nonwoven fabric. That is, the filament mixture which forms one of the surfaces of the spunbonded nonwoven fabric to be manufactured first strikes in the moving direction of the collection belt 7. Next, the filament or filament mixture forming the inner region of the spunbonded nonwoven is placed in place while the filament mixture of the first type of impact is flowed and conveyed. This emplacement is carried out until the filament mixture forming the second surface of the spunbond nonwoven fabric finally hits the mixture on the belt 7.

FIG. 3 shows the above embodiment. The upper half of FIG. 3 shows three rectangular spinning nozzle plates 3 arranged so that their longitudinal axes are parallel to the running direction of the collecting belt 7. Is shown. Due to the arrangement 3a of the spinning holes 5, 6 on the spinning nozzle plate 3, a spunbond in which the surface initially set on the belt 7 is very flexible containing a lot of type a filaments discharged from the spinning holes 5 A non-woven fabric is obtained. This surface on the side of the collection belt 7 is gradually discharged from the spinning hole 6 as the setting time becomes longer.
It is covered with an increasing amount of type b bicomponent filaments. Finally, another surface of the spunbond nonwoven is formed, which surface is rich in filaments of type b,
It has hardness and robustness corresponding to this.

Using one or more spinning nozzle plates 3 of FIG. 3b, a spunbond nonwoven fabric having a surface rich in bicomponent filaments of type b on the collecting belt side as described above is obtained. And a large number of spinning holes 6 arranged in the upper portion of the spinning nozzle plate 3. As the operating time of the apparatus increases in one working step, the inner cross-sectional area of the spunbonded nonwoven fabric, which is rich in type a filaments, is formed (spinning holes in the central part of the spinning nozzle plate 3). 5 is used). The continuous reduction of type a filaments eventually results in a second surface.

When the apparatus shown in FIG. 3C is used, the surface on the side of the collecting belt 7 contains 85% by weight or less of the filament of the type a, and the content of the bicomponent filament of the type b is continuously increased to the inside in the other cross section. The spunbonded nonwoven fabric is made such that is increased to 70% by weight. The surface of the spunbonded nonwoven fabric on the side opposite to the collecting belt 7 also comprises in this variant embodiment 85% by weight of type a core / sheath filaments, the remainder being type b filaments.

Considering additionally FIG. 3d in this connection, FIG. 3d corresponds to a variant of FIG. 3a. In this case, only the spinning nozzle plate 3 is oriented transversely to the running direction of the collecting belt 7, the longitudinal axis of which corresponds to the length of the spunbond nonwoven to be produced. A variant of this variant embodiment is also shown in FIG. 2a and is labeled a3 above.

It is also possible to arrange a plurality of rectangular spinning nozzle plates 3 or round spinning disks 4 in series with one another. In this case, as shown in a variant embodiment a1 of FIG. 2a, the longitudinal axis of the spinning nozzle plate 3 is parallel to the running direction when viewed in the running direction of the collection belt 7, and is arranged laterally to the running direction. Have been. Correspondingly, according to the variant embodiment a2, the spinning disk 4 is arranged on an imaginary line transverse to the running direction of the collecting belt 7.

In the modified embodiments a1 and a2 of FIG. 2, between the spinning nozzle plate 3 or the spinning disk 4 and the collecting belt, the filaments leaving the spinning holes 5, 6 are arranged in a direction transverse to the drop direction. In addition, the air flow for floatingly guiding in the transverse direction with respect to the running direction of the collection belt 7 or the longitudinal axis of the spinning nozzle plate 3 to obtain a uniform cross section of the spunbonded nonwoven fabric in the transverse direction with respect to the running direction is generated. is necessary. The technology of the air flow guided in a floating manner belongs to the prior art, and even if it is not provided, it can be easily added to most devices.

According to another variant embodiment of the device, it is arranged obliquely with respect to the conveying direction of the collecting belt 7 and in parallel, in series or obliquely stepwise with respect to the plane of the collecting belt. A rectangular spinning nozzle plate 3 is provided. This is illustrated in b1 and b2 in FIG. 2b in two alternative embodiments. Also in this stepped arrangement, the filaments leaving the spinning holes 5 and 6 are floated and guided by airflow in a direction transverse to the dropping direction and in a direction transverse to the running direction of the collection belt 7, and the spunbond nonwoven fabric A constant yarn mixing is obtained inside each side of the.

A number of possible arrangements of the protection devices 3 and 4 with respect to the collecting belt 7 described here (of which FIG. 2 only exemplifies some expedient possibilities)
Offers the great advantage that the device according to the invention can be very easily integrated into existing device systems for monofilament spinning. Only the arrangement of the spinning holes 5, 6 and the melt sorting and distribution system for separately forming the core / sheath filaments of different materials need to be changed.

That is, the present invention can be carried out in an existing apparatus with a minimum of recombining procedures, and the apparatus is arranged so that the spinning nozzle plate is directed transversely or along the running direction of the collecting belt. It does not matter whether it is configured for a spinning disk or whether the configuration in which the spinning nozzle plate is arranged at an oblique angle is fundamental to the concept of the device provided.

[0038]

As described above, according to the present invention, the type a
And a nonwoven fabric comprising two types of bicomponent filaments of type b, wherein the weight ratio of these two types changes smoothly from one surface to the other. This allows
Various nonwoven fabrics suitable for various applications can be easily formed,
In addition, there is no problem of delamination.

[Brief description of the drawings]

FIG. 1 shows two types of bicomponent filaments a and b, each comprising a core 1 which melts at a higher temperature and a jacket 2 which melts at a lower temperature, 2a with respect to the weight of the jacket component at the same filament count. : 2b ratio is 1: 3
FIG. 3 is a diagram exemplarily showing types a and b in which ｂ is 1:10. The description of the melting characteristics of the core / sheath materials 1 and 2 forming the bicomponent filaments assumes that the same melting point measurement method is applied to the materials 1 and 2.

FIG. 2 is a view showing a different arrangement of a spinning nozzle with respect to a moving collecting belt.

FIG. 3 is an exemplary view showing various modifications regarding the arrangement of spinning holes arranged in a rectangular spinning nozzle plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 core 2 jacket 3 spinning nozzle plate 4 spinning disk 5,6 spinning hole 7 collection belt

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Norbert Gaufinck, Lönnstrasse 64, Neunkirchen, Germany 64 (58) Fields investigated (Int. Cl. ⁶ , DB name) D04H 1/00-18/00

Claims (8)

(57) [Claims] 1. A spunbond nonwoven fabric comprising a bicomponent filament of type (a) and a bicomponent filament of type (b) having the same number, wherein each of said bicomponent filaments is an adhesive polymer material. And a core material (1) made of polyethylene terephthalate, which melts at a higher temperature than the jacket material (2). The filament jacket material (2a) of the type (a) Weight ratio 2a of the sheath material (2b) of the filament of (b):
2b is 1: 3 to 1:10, and the weight ratio of the filament of the type (a) to the filament of the type (b) is from one surface to the other surface along the vertical cross section of the spunbonded nonwoven fabric. The filaments of type (b) are different so that they vary in the range of 15 to 70% by weight, and the weight ratio of filaments of type (a) to filaments of type (b) is identifiable in the vertical cross section of the spunbond nonwoven A spunbonded nonwoven fabric characterized in that the spunbonded nonwoven fabric is changed without generating a phase boundary. 2. The spunbonded nonwoven fabric has a bicomponent filament content of type (b) on one surface higher than a bicomponent filament content of type (b) on the other surface, and the one surface is hard and hot melted. Has adhesive properties,
The spunbonded nonwoven fabric according to claim 1, wherein the other surface is flexible and does not have hot-melt adhesiveness. 3. The content of the type (b) bicomponent filament in the interior of the spunbond nonwoven fabric is relatively higher than the content of the type (b) bicomponent filament in the surface of the spunbond nonwoven fabric, and the content of the bicomponent filament toward the outside is higher. The spunbonded nonwoven fabric according to claim 1, wherein the nonwoven fabric has two flexible surfaces, and the inside is formed to be harder than the two surfaces. 4. The two surfaces of the spunbonded nonwoven fabric are high in the content of type (b) bicomponent filaments and are hard, and the interior of the spunbonded nonwoven fabric is of a type (b) type compared to the two surfaces. Component filament content is low,
2. The structure according to claim 1, wherein the structure is more flexible.
The spunbonded nonwoven fabric according to 1. 5. An apparatus for producing a spunbond nonwoven fabric according to claim 1, comprising 1 to 40 rectangular spinning nozzle plates (3) or circular spinning disks (4). These spinning nozzle plates (3) or spinning disks (4) are provided with spinning holes (5,6) and above the drafting device for the filaments discharged from the spinning holes (5,6). Are located,
In a device provided with a transfer device provided below a drafting device with a collecting belt (7) for a filament which can be moved linearly in a horizontal direction, a spinning nozzle plate (3) or a spinning disk (4) is provided. Each having a spinning hole (5) for discharging a bicomponent filament of type (a) from the melt, and a spinning hole (6) for discharging a bicomponent filament of type (b) from the melt;
The order of the spinning holes (5,6) so that the spinning from the entire spinning holes (5,6) onto the collecting belt (7) corresponds to the density distribution of the bicomponent filaments in the vertical cross section of the spunbond nonwoven. And the bicomponent filament mixture forming one surface of the spunbond nonwoven along the direction of movement of the collection belt (7) is first spun and impinges on the collection belt (7), The bicomponent filament mixture forming the inner region of the bonded nonwoven is spun and placed over the first bicomponent filament;
Finally, the apparatus is characterized in that the bicomponent filament mixture forming the other surface of the spunbond nonwoven is placed on the preceding bicomponent filament mixture that has been conveyed. 6. At least one rectangular spinning nozzle plate (3) extending transverse to the direction of movement of the collecting belt (7) and having a length corresponding to the width of the spunbond nonwoven to be produced. 6. The device according to claim 5, wherein 7. A plurality of rectangular spinning nozzle plates (3) or circular spinning disks (4) are provided in series, the series being arranged so as to cross the conveying direction of the collecting belt (7). And spinning nozzle plate (3)
Alternatively, a device for generating an air flow is provided between the spinning disk (4) and the collection belt (7), and this air flow causes the filaments discharged from the spinning holes (5) and (6) to flow in the falling direction. To the transverse direction and transverse to the running direction of the collecting belt (7) or the spinning nozzle plate (3)
6. The device according to claim 5, characterized in that it is guided in a transverse direction with respect to the longitudinal axis of the device. 8. A plurality of steps arranged obliquely with respect to the direction of movement of the collecting belt (7) and parallel to the surface of the collecting belt (7), in series or one after the other in a stepwise manner. A rectangular spinning nozzle plate (3) is provided, and a device for generating an air flow between the spinning nozzle plate (3) and the collecting belt (7) is provided. This air flow is supplied to the spinning holes (5) and (6). ) Floating guides transversely to the direction of their drop and transversely to the running direction of the collecting belt (7) or transversely to the longitudinal axis of the spinning nozzle plate (3). Apparatus according to claim 5, characterized in that the apparatus is adapted to: