JPH08232152A - Zebra pattern-imparted nonwoven fabric and its production - Google Patents

Abstract

PURPOSE: To obtain a zebra pattern-imparted nonwoven fabric rich in flexibility by laminating a short fiber web on one surface of a long fiber web each having a biodegradability and making these into one unit by a water jet punching method. CONSTITUTION: This method for producing a zebra pattern imparted nonwoven fabric comprises laminating the long fiber web of an aliphatic polyester, etc., on the one surface of the short fiber web layer of reclaimed wool, etc., each having a biodegradability, treating it on a porous supporting board having >=250 mesh by a high pressure fluid flow jet device having the jet nozzles arranged uniformly in its width direction to form a small area open holes region A where <=17×10<-2> mm<2> open hole area X, >=350/cm<2> open hole distribution density Y and 30-60% area ratio of open holes Z satisfy X×Y=Z, and the fibers at the non-open hole part intertwine each other three dimensionally, then treating it on a porous supporting board having <=25 mesh by a jet device having specifically arranged jet nozzles to form a large area open holes region B where <=30×10<-2> mm<2> X, <=100/cm<2> Y and 30-70% Z satisfy X×Y=Z and the fibers at the non-open hole part intertwine three dimensionally in a higher degree than that in the region A to obtain the nonwoven fabric provided the surface regions A and B alternately in one direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called spunlaced non-woven fabric in which a high-pressure liquid flow is applied to a laminated web, and more specifically, it is a non-woven fabric having a zebra pattern and decomposed in the natural world. The present invention relates to a non-woven fabric composed of possible short fibers and long fibers and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, as a method of imparting a pattern to a non-woven fabric, a printing method or a method of imparting a pattern under the condition of pressurizing and heating using an engraving roll in which the pattern is engraved on a roll is generally used. Known to be.

However, the printing method has a drawback in that the nonwoven fabric is required to have a certain hardness or more, and a flexible nonwoven fabric has a poor printing definition. In addition, in the method of imparting a pattern with an engraving roll, the heated engraving roll is pressed to impart the pattern, so that the flexibility of the nonwoven fabric is impaired.

On the other hand, a spunlace non-woven fabric is mentioned as a non-woven fabric having flexibility, and the pattern of the spun lace non-woven fabric is provided by forming openings. The openings are affected by the material of the porous support plate that supports the nonwoven web, the thickness of the net yarn, the structure, etc.
Although there are flats, twills, ridges, etc., spunlaced nonwoven fabrics obtained with these porous support plates have uniform openings (voids) over the entire surface.
And its performance is uniform.

Further, as a method of partially imparting a pattern to the spunlaced nonwoven fabric, a porous web having a pattern portion in which the porosity of the pattern portion is further changed is formed on a non-woven web placed on a porous support plate. There is a method of stacking a flexible support plate and allowing a high-pressure liquid flow to act from above. According to this method, the high-pressure liquid flow passes only through the apertures of the porous support plate having the pattern portion, thereby imparting the apertures of the porous support plate on which the nonwoven web is placed to the nonwoven web. How to do it is provided. However, this method has a problem in that the non-woven fabric as a whole lacks in compactness because the pattern is formed in the non-woven fabric by changing the size and shape of the openings of the porous support plate having the pattern portion. Is the current situation. That is, the pattern portion through which the high-pressure liquid flow does not pass is not three-dimensionally entangled, so that the mechanical properties of the portion are inferior, and the shape retention of the entire nonwoven fabric is inferior. Further, the non-woven fabric obtained by this method is a non-woven fabric to which specific open pores are provided, in which partially different open pores from the open pores are provided, and there is a drawback that the sharpness of the pattern is poor. There is.

As the fiber material constituting these non-woven fabrics, synthetic polymers such as polyethylene, polypropylene, polyester and polyamide are mainly mentioned. Nonwoven fabrics made of these materials have no self-degradability and are chemically very stable under normal natural environment. Therefore, the disposable nonwoven fabric is treated by incineration or landfill after use. However, there is a problem that pollution occurs in the incineration process, and there is a problem that the original state remains in the soil for a long time in the landfill process because the material is chemically stable.

[0007]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned situation, and is a non-woven fabric which is provided with a non-uniform pattern clearly on the entire surface and which has excellent mechanical properties and is flexible. Therefore, it is an object of the present invention to provide a nonwoven fabric which is naturally decomposed within a short period of time.

[0008]

The inventors of the present invention have arrived at the present invention as a result of intensive research to achieve the above object. That is, the present invention, a long fiber web layer having biodegradability is arranged on one surface of a short fiber web layer having biodegradability,
A non-woven fabric in which both webs are integrated with each other, a small area of openings is formed with a high arrangement density, and a non-opening area has a region A in which fibers are three-dimensionally entangled, and a large area of openings. Are formed with a low disposition density, and in the non-perforated part, the area A between the fibers is the area A
Dense area B that is highly three-dimensionally entangled than the non-open area of
And are alternately provided in one direction in the non-woven fabric, which is a gist of the non-woven fabric having a zebra pattern.

Further, a non-woven web having a biodegradable long fiber web layer on one side of a biodegradable short fiber web layer is placed on a fine mesh porous support plate, and injection holes are formed. Forming a hole in a portion corresponding to the hole of the mesh by performing a first-stage high-pressure liquid flow treatment using a high-pressure liquid flow injection device uniformly arranged in the width direction,
The three-dimensional entanglement is given between the fibers existing in the non-opened area, both web layers are integrated, and then placed on the coarse mesh porous support plate, and the injection holes are uniformly arranged in the width direction. The high-pressure liquid flow injection device in which the high-pressure liquid flow injection device in which the open regions and the regions in which the injection holes are not provided are alternately arranged in the width direction is subjected to the second-stage high-pressure liquid flow treatment, and thus the openings of the mesh are opened. It is characterized in that an opening is formed at a corresponding portion and a higher degree of three-dimensional entanglement is provided between the fibers existing in the non-opening portion than that obtained by the high pressure liquid flow treatment of the first stage to provide a dense structure. The gist is a method for producing a non-woven fabric having a zebra pattern.

Next, the present invention will be described in detail. As the biodegradable short fibers used in the present invention, natural fibers typified by cotton, regenerated fibers obtained from pulp, and short fibers obtained from a biodegradable thermoplastic polymer can be used. .

As the cotton fiber, there can be used unbleached combed yarn, bleached bleached cotton, and fluff obtained from cotton yarn or woven or knitted fabric. The term "back hair" as used in the present invention means one that is simply bleached, one that is exposed to fluorescence, and one that is dyed.

Examples of the anti-hair-removing machine that can effectively obtain the anti-hair-removing material that can be used in the present invention include a ratg machine, a notch breaker, a garnet machine, and a turning machine. The type and combination of anti-fluffing machines to be used depend on the shape of the fabric to be fluffed, the thickness of the threads and the strength of the twist, but two or more of the same anti-fluffing machines can be connected in series. It is effective to use a combination of the above anti-fluffing machines. The defibration rate by the fluffing machine is preferably in the range of 30 to 95%. If the defibration rate is less than 30%, not only defibrated fibers are present in the card web and the surface of the nonwoven fabric is rough, but also when the laminated nonwoven web is treated with the liquid columnar flow, the liquid columnar flow is not generated. It is not preferable because it does not sufficiently penetrate the defibrated fiber portion. If the defibration rate exceeds 95%, sufficient surface friction strength cannot be obtained, which is not preferable. The defibration rate is obtained by the formula shown below. Disentanglement rate (%) = (LM) × 100 / L In the above formula, L is the weight of fluff, and M is the weight of undisentangled fiber.

Regenerated fibers obtained from the pulp used in the present invention include viscose rayon, cellulose acetate rayon, and solvent-spun rayon lyocell.

The biodegradable thermoplastic synthetic long fibers and short fibers used in the present invention are the fibers obtained by the ordinary spinning method of the following polymers. The polymer is a biodegradable thermoplastic aliphatic polyester polymer, for example, a polymer composed of polyglycolic acid or polylactic acid such as poly (α-hydroxy acid) or a copolymer thereof. In addition, poly (ε-caprolactone), poly (ω-hydroxyalkanoate) such as poly (β-propiolactone), poly-3-hydroxypropionate, poly-3-hydroxybutyrate, etc. , Poly-3-hydroxycaprolate, poly-3-hydroxyheptanoate, poly-3-hydroxyoctanoate and their copolymerization with poly-3-hydroxyvalerate and poly-4-hydroxybutyrate. Such poly (β-hydroxyalkanoates) can be mentioned. Further, as a polycondensate of glycol and dicarboxylic acid, for example, polyethylene oxalate, polyethylene succinate, polyethylene adipate, polyethylene azelate, polybutylene oxalate, polybutylene succinate, polybutylene adipate, polybutylene sebacate, Examples thereof include polyhexamethylene sebacate, polyneopentyl oxalate, and copolymers thereof. Furthermore, the aliphatic polyester and polycapramide (nylon 6), polytetramethylene adipamide (nylon 66), polyundecanamide (nylon 11), polylaurolactamide (nylon 12)
Examples thereof include aliphatic polyesteramide-based copolymers that are copolymers with aliphatic polyamides. In the present invention, any biodegradable one can be used.

The nonwoven fabric of the present invention is a nonwoven fabric having a three-dimensional entanglement. With a non-woven fabric having a three-dimensional entanglement,
The fibers constituting the laminated nonwoven web having the short fiber nonwoven web layer carded on at least one surface of the long fiber nonwoven web layer are entangled not only in the transverse direction but also in the thickness direction, It means a non-woven fabric having an integrated structure. This integrated structure is formed by the main entanglement of constituent fibers, and has a higher bulk density than laminated nonwoven webs. In the present invention, the nonwoven fabric having a three-dimensional entanglement is a spunlace nonwoven fabric obtained by the water jet punch method.

In the nonwoven fabric of the present invention, regions A and regions B are alternately provided in one direction in the nonwoven fabric. Area A is
It is obtained by placing a laminated nonwoven web on a fine porous support plate and subjecting it to a high-pressure liquid flow treatment. It is an area that is originally entangled and has functions such as ventilation blocking, light blocking, heat retention, and water absorption.

The opening area has an opening area of 17 × 10 ^-2 mm.
It is preferable that the density is ² or less, the hole arrangement density is 350 holes / cm ² or more, and the open area ratio is 30 to 60%. These relationships are represented by the following formula. In the following formula, X is the open area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), and Z is the open area ratio (%).

X × Y = Z The opening area exceeds 17 × 10 ^-2 mm ² and the hole arrangement density is 3
If it is less than 50 pieces / cm ² , a clear difference in the opening does not appear between the area B and the sharpness of the pattern and the pattern is inferior, which is not preferable, and sufficient ventilation barrier property, light shielding property, heat retaining property, water absorption property, etc. Is not preferable because the function of can not be maintained.

If the open area ratio is less than 30%,
The degree of entanglement of the fibers forming the non-woven fabric is weak and sufficient non-woven fabric strength cannot be obtained, resulting in poor mechanical strength, which is not preferable, and when it exceeds 60%, the ventilation blocking property, the light shielding property and the heat retaining property are deteriorated. It becomes scarce and is not preferable.

Considering the productivity of the nonwoven fabric, the open area is 0.86 × 10 ^{-2 to} 17 × 10 ^-2 mm ² , the hole arrangement density is 350 to 3500 pieces / cm ² , and the open area ratio. Is 30
It is more preferably -60%.

Region B is obtained by placing the laminated nonwoven web on a coarse porous support plate and subjecting it to a high pressure liquid flow treatment, with large areas of apertures being formed at low placement density and non-woven. In the open pores, the fibers are three-dimensionally entangled to a higher degree than in the non-open pores in the region A, and a dense structure is provided, so that air permeability and
This is a region having a function such as translucency.

The opening area has an opening area of 30 × 10 ^-2 mm.
It is preferable that the density is ² or more, the hole arrangement density is 100 holes / cm ² or less, and the open area ratio is 30 to 70%. The relationship between these is represented by the following formula. In the following formula, X is the open area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), and Z is the open area ratio (%).

X × Y = Z If the opening area is less than 30 × 10 ^-2 mm ² and the hole arrangement density exceeds 100 holes / cm ² , there is a clear difference between the areas and the area A. It is not preferable because it does not appear and the sharpness of the pattern is inferior, and sufficient functions such as air permeability and translucency cannot be maintained. Further, if the open area ratio is less than 30%, sufficient air permeability and translucency cannot be obtained, which is not preferable.
If it exceeds%, the morphological stability becomes poor and sufficient nonwoven fabric strength cannot be obtained, which is not preferable.

Considering the morphological stability of the non-woven fabric, the opening area is 30 to 430 × 10 ^-2 mm ² , and the pore arrangement density is 16
It is more preferable that the opening area ratio is from about 100 / cm ² and the opening area ratio is from 30 to 70%.

Next, the manufacturing method of the present invention will be described. The nonwoven fabric of the present invention can be obtained by the following four major steps. First, as a first step, the short fibers having biodegradability are carded by a carding machine to produce a short fiber non-woven web. This short-fiber non-woven web is a parallel card web in which the fibers are arranged in the traveling direction of the card machine, a cross-laid web in which the parallel card webs are cross-laid, or a cross-laid post-drafted web depending on the degree of fiber arrangement. Either a web in which the longitudinal / horizontal fiber arrangement is changed and a random card web randomly arranged, or a semi-random card web in which both of them are moderately arranged is selected.

Next, in the second step, a biodegradable synthetic long fiber nonwoven web is prepared by a spunbond method using a polymer selected from the biodegradable thermoplastic resins. That is, melt spinning is performed using one or a plurality of polymers selected from the biodegradable thermoplastic resins. After the yarn spun from the spinneret is cooled by a known cooling device, it is taken up by air sucker, the yarn is opened using a corona discharge device, etc., deposited on a moving deposition device, and then partially heat-bonded. To obtain a spunbonded nonwoven fabric.
This partial heat bonding means that the web corresponding to the engraved pattern is formed by passing the web between a roll having an engraved pattern on the surface, that is, an embossing roll and a metal roll having a smooth surface, under heating conditions. This is to thermally bond the constituent fibers together. More specifically, this partial thermal bonding has a certain area relative to the total surface area of the biodegradable long fiber nonwoven web layer, ie the individual thermal bonding areas do not necessarily have to be circular. But 0.1-1.0m
It has an area of m ² and its density, that is, the pressure contact density is 2 to
It is 80 points / cm ² , preferably 4 to 60 points / cm ² . If the bond point density is less than 2 points / cm ² , the mechanical properties and shape retention of the web layer after heat bonding will not be improved, while if the bond point density exceeds 80 points / cm ² , flexibility will be increased. It is deteriorated and the spreadability is inferior, which is not preferable.

The area ratio of the total heat-bonded area to the total surface area of the biodegradable long-fiber nonwoven web layer, that is, the bonded area ratio is preferably 2 to 30%, more preferably 4 to 20%. If the bonding area ratio is less than 2%, the dimensional stability of the biodegradable long-fiber non-woven web layer after heat-bonding is not improved, and therefore the biodegradable long-fiber non-woven web layer has a short biodegradability. The laminated non-woven web obtained by laminating the fibrous non-woven web layers has poor dimensional stability, which is not preferable.

In the above steps 1 and 2, the basis weight of the short fiber non-woven web is preferably 20 g / m ² or more and less than 180 g / m ² , and the basis weight of the long fiber non-woven web is 10 g.
/ M ² or more and less than 50 g / m ^{2 and} the basis weight of the laminated nonwoven web is 30 g / m ² or more and 200 g / m ² or more.
It is preferably m ² or less. When the basis weight is less than 30 g / m ² , the thickness of the nonwoven web is insufficient, and the region A is placed on the porous support plate with fine mesh and subjected to the entanglement treatment, and the porous support plate with coarse mesh. It is not preferable because the difference from the region B placed on the surface and subjected to the confounding process is not clear. Further, the morphological stability of the nonwoven fabric cannot be maintained, which is not preferable. On the other hand, when the basis weight exceeds 200 g / m ² , the processing energy of the high-pressure liquid flow for performing the entanglement treatment on the laminated non-woven web placed on the porous support plate becomes large, and the short fiber failure occurs under the extreme processing conditions. The fibers are not entangled in the inner layer of the woven web,
As a result, not only practical mechanical properties are not obtained, but also the thickness of the laminated nonwoven web becomes excessively large, and the difference in hole shape between the regions A and B becomes unclear, which is not preferable. For the above reason, the basis weight of the web is 30 g / m ^{2 to} 200 g / m ²
Range, more preferably 50 g / m ^{2 to} 150 g
The range is / m ² .

Then, in a third step, the laminated non-woven web obtained above is subjected to a so-called spun lace method, that is, a high-pressure liquid flow is applied to the laminated non-woven web placed on the porous support plate. Get lace nonwoven.
In this step, a laminated nonwoven web placed on a fine porous support plate is subjected to high-pressure liquid flow treatment to obtain a laminated nonwoven fabric having three-dimensional entanglement and integrating both webs. Is. Then, the laminated non-woven web subjected to the entanglement treatment by the above-mentioned method is introduced onto a coarse porous support plate, and a pore shape different from the pore shape given by the fine porous support plate is opened. By applying the laminated support web in the width direction of the laminated nonwoven web, different pore shapes are alternately provided in the width direction of the nonwoven web to obtain a nonwoven fabric having a pattern as a whole.

This process will be described in more detail. A laminated non-woven web obtained by laminating a biodegradable short fiber non-woven web and a biodegradable long fiber non-woven web is placed on a fine porous support plate and jetted. The high pressure liquid flow treatment of the first stage is performed by using a high pressure liquid flow injection device in which the holes are uniformly arranged in the width direction of the nonwoven web.

The mesh range of the porous support plate used in the first-stage high-pressure liquid flow treatment uses a finer mesh than that of the porous support plate used in the second-stage high-pressure liquid flow treatment, preferably 50 mesh. (50 / 25m
m) or more is used. If a mesh that is the same as or coarser than the porous support plate used in the second-stage high-pressure liquid flow treatment is used, no pattern is imparted. Fifty
If it is less than the mesh, there will be a sharp difference in the opening between the openings provided in the laminated nonwoven web in the first-stage high-pressure liquid flow treatment and the openings provided in the subsequent second-stage high-pressure liquid flow treatment. It is not preferable because it does not appear and the definition of the pattern is poor. Further, it is not preferable because it can retain sufficient functions of ventilation blocking property, light blocking property, heat retaining property, water absorbing property and the like. On the other hand, the range of the mesh of the porous support plate is 15
If it exceeds 0 mesh, the energy cost required for the entanglement of the laminated nonwoven web becomes large, which is not preferable in terms of production cost. Therefore, considering productivity and the like, the range of 50 to 150 mesh is preferable, and the range of 50 to 100 mesh is more preferable.

As a high-pressure liquid jet device for performing the confounding treatment, there are a plurality of orifices in which jet holes each having a hole diameter of 0.05 to 1.5 mm are arranged in one row or a plurality of rows with an injection hole interval of 0.5 to 5 mm. A device may be used in which the orifice heads are arranged in stages and the injection holes are evenly arranged in the width direction.

When the high-pressure liquid flow is made to collide with the laminated nonwoven web placed on the porous support plate, the orifice head provided with the injection holes is moved toward the advancing direction of the laminated nonwoven web. It is advisable to oscillate the orifice head at the same intervals as the injection hole intervals in the direction perpendicular to each other and eject the high-pressure liquid flow to make it uniformly collide. A high-pressure liquid stream, which is ejected in a columnar shape at high pressure from an injection hole, is made to collide from above the laminated nonwoven web to form an opening at a site corresponding to the opening portion of the mesh and the fibers constituting the laminated nonwoven web are separated from each other. Three-dimensionally entangled and integrated. As the liquid, room temperature water or hot water can be used.

When the high pressure liquid stream is jetted in this step, the porous support plate on which the laminated non-woven web is placed should have a structure such that the high pressure liquid flow can pass through the laminated non-woven web on the support plate. For example, it may be made of metal, polyester, or other material.

This first-stage high pressure liquid flow treatment is preferably performed at least twice. That is, in the first entanglement treatment, a high-pressure liquid flow having a water pressure of less than 40 kg / cm ² G is applied to pre-entangle the short fiber nonwoven web. In the first entanglement treatment, when the water pressure is 40 kg / cm ² G or more, the accompanying air flow generated by the high-pressure liquid flow causes disturbance of the short fiber non-woven web portion, which is preferable in terms of weight unevenness and maintaining the quality of the nonwoven fabric. Absent. The laminated nonwoven web which has been subjected to the first preliminary entanglement is subsequently subjected to the entanglement treatment of the second and subsequent entanglements several times by a high pressure liquid flow having a water pressure of 50 kg / cm ² G or more.

Furthermore, the laminated non-woven web obtained by the above-mentioned method is reversed by the basis weight of the laminated non-woven web and subjected to the entanglement treatment with the hydraulic pressure applied in the second time as the third and subsequent entanglement treatments, and the front and back sides are three-dimensionally processed. It can be a non-woven web that is entangled in a mechanical manner.

By performing the first-stage high-pressure liquid flow treatment in this manner, an opening is formed in a portion corresponding to the opening of the mesh, and three-dimensional entanglement occurs between fibers existing in the non-opening. Give.

Next, a method of applying a second-stage high-pressure liquid flow treatment to give a pattern in one direction will be described. The laminated non-woven web obtained by performing the first-stage high-pressure liquid flow treatment is placed on a coarse porous support plate, and the injection holes are uniformly arranged in the width direction and the injection holes. The second-stage high-pressure liquid flow treatment is performed by using the high-pressure liquid flow injection device in which the regions in which are not arranged are alternately arranged in the width direction.

The mesh range of the porous support plate used in the second-stage high-pressure liquid flow treatment is one having a coarser mesh than that of the porous support plate used in the first-stage high-pressure liquid flow treatment, preferably A mesh of 25 mesh (25/25 mm) or less is used. If the same mesh as or finer than the porous support plate used in the first-stage high-pressure liquid flow treatment is used, the three-dimensionally entangled fiber bundle is porous-supported by the first-stage high-pressure liquid flow treatment. The plate cannot be sufficiently moved along the mesh of the plate to provide the holes by the high pressure liquid flow treatment of the second stage, and the pattern is not provided. In addition, it is not preferable because it cannot retain sufficient functions such as air permeability and translucency. When it exceeds 25 meshes, the difference in the opening clearly appears between the opening given to the laminated nonwoven web by the high pressure liquid flow treatment of the first stage and the opening given by the high pressure liquid flow treatment of the second stage. It is not preferable because it is difficult and the pattern definition tends to be poor.
On the other hand, when the mesh becomes too coarse, for example, when the mesh size is 10 mesh or less, the pores become clear, but the morphological stability of the nonwoven fabric cannot be maintained, which is not preferable. Therefore, considering the morphological stability of the nonwoven fabric, the preferable range of the mesh of the porous support plate used is 10 to 25 mesh.

As the injection holes used in the second-stage high-pressure liquid flow treatment, those used in the first-stage high-pressure liquid flow treatment can be used.

In the high-pressure liquid flow injection device used for the second-stage high-pressure liquid flow treatment, the regions in which the injection holes are uniformly arranged in the width direction and the regions in which the injection holes are not arranged alternate in the width direction. For example, an orifice in which a high-pressure liquid flow is injected with an injection hole having a specific width and a non-arranged portion with a constant width is arranged next to the portion where the injection hole is arranged. Equipment used, Orifice heads that can regulate the width to which holes are provided by adjusting the placement angle and placement position with a plurality of orifice heads that can move in the width direction of the laminated nonwoven web. Examples of such devices include:

The water pressure during the second stage high pressure liquid stream treatment may be lower than the water pressure during the first stage high pressure liquid stream treatment. By performing the second-stage high-pressure liquid flow treatment, the fiber bundles three-dimensionally entangled by the first-stage high-pressure liquid flow treatment are moved along the mesh of the coarse porous support plate,
A unidirectional pattern is imparted to the non-woven fabric, and three-dimensional entanglement higher than the three-dimensional entanglement by the first-stage high-pressure liquid flow treatment is provided between the fibers present in the non-opened portions, resulting in a dense structure. Also, the first
If a high water pressure is used compared to the water pressure during the high-pressure liquid flow treatment of the stage, the fibers existing in the non-opened areas are highly three-dimensionally entangled to form a dense structure, and the fiber density is high and the strength of the nonwoven fabric is improved. .

Using the above apparatus, the orifice head is oscillated in the direction perpendicular to the traveling direction of the laminated nonwoven web at the same intervals as the injection hole intervals to eject a high-pressure liquid stream. Then, the high-pressure liquid flow is injected into the region where the injection holes are evenly arranged in the width direction to form the openings at the portions corresponding to the openings of the mesh and the fibers existing in the non-opened areas. In the meantime, a non-woven fabric having a dense structure with three-dimensional entanglement higher than that obtained by the first-stage high-pressure liquid flow treatment is obtained (region B), while the region where the injection holes are not arranged is , The high-pressure liquid stream is not jetted (area A).

The widths of the regions A and B are determined by the widths of the regions where the injection holes of the high-pressure liquid flow injection device used for the second stage high-pressure liquid flow treatment are disposed and the regions where they are not disposed. It may be selected, but the arrangement interval (A / B) between the area A and the area B 1
It is usually set to 0 to 1000 mm / 10 to 1000 mm in view of general non-woven fabric applications.

For example, when it is used for clothing, it is preferable that the widths of the regions A and B are alternately arranged at intervals of 10 to 50 mm to form a pattern.

When used as an agricultural sheet, the area A is a portion that functions as a light-shielding or air-permeable property, and the area B is a portion that functions as a light-transmitting or air-permeable material. The widths of the area A and the area B may be set according to the purpose. For example, in an agricultural sheet that is stretched in a tunnel shape in the summer, the translucent portion (area A) of the solar radiation in the summer is formed in the center of the stretched sheet in the range of 50 to 70% of the entire sheet. , 20-40% on both sides
To form a portion (area B) that functions as a breathable material and is formed on the both sides of the portion (area B) that functions as a breathable material.
Is formed in the range of 10 to 30%. In winter use, by changing the arrangement of the region A and the region B, it is possible to secure the light-transmitting property, prevent the infiltration of cold air, and promote the growth of seedlings inside the sheet. As described above, the widths of the area A and the area B may be appropriately selected depending on the application.

When stretched in a tunnel shape as an agricultural sheet, the long-fiber nonwoven web side made of synthetic fiber having biodegradability is the outside air side, and the short-fiber nonwoven web has a water-absorbing natural property. By laying the short fiber non-woven web side using fibers and recycled fibers inside, it is possible to prevent night dew from adhering to the sheet and prevent evaporation of water inside the sheet due to temperature rise. You can also expect to do it.

When used as a material which comes into contact with the skin for clothing or the like, for example, the long fiber nonwoven web side made of synthetic fiber having biodegradability is the side in contact with the skin, and the short fiber nonwoven web is a natural fiber having water absorbency. • Place the short fiber non-woven web side using recycled fibers on the side that does not contact the skin. By doing so, moisture from the skin migrates through the long-fiber non-woven web made of synthetic fibers to the short-fiber non-woven web side made of natural fibers and regenerated fibers having water-retaining and water-absorbing properties, and the surface in contact with the skin. The discomfort is eliminated without the product getting wet. As described above, the material of the fibers to be laminated may be appropriately selected depending on the application.

Subsequently, in a fourth step, excess moisture of the laminated nonwoven web obtained as described above is removed by a known moisture removing device such as mangle, and further dried by a hot air circulation dryer of the saxion band system. A non-woven fabric having flexibility and three-dimensional entanglement which is treated to obtain a non-woven fabric of the present invention in which regions having different opening areas and different pore arrangement densities are alternately provided in one direction and a zebra pattern is provided. is there.
By going through the above-mentioned steps 1 to 4, it is possible to obtain a flexible non-woven fabric having a three-dimensional entanglement treatment and pores and forming a pattern in one direction.

[0050]

The nonwoven fabric of the present invention has the above-mentioned constitution, and in the area A, the small-area open holes are formed with a high arrangement density by the first-stage high-pressure liquid flow treatment by the fine porous support plate, and In the open area, the fibers are three-dimensionally entangled, which is an area having functions such as ventilation blocking, light blocking, heat retention, and water absorption. On the other hand, in the region B, the porous support plate used in the first-stage high-pressure liquid flow treatment has a large area of low-pore openings due to the second-stage high-pressure liquid flow treatment using the coarse porous support plate. The fibers are densely formed, and in the non-opened area, the fibers are three-dimensionally entangled to a higher degree than in the non-opened area in the region A to provide a dense structure, and functions such as air permeability and light transmission. It becomes the area which has.

Therefore, in comparison with the porous support plate used in the first-stage high-pressure liquid flow treatment, a coarser porous support plate was used, and the laminated non-woven fabric obtained in the first-stage high-pressure liquid flow treatment was used. The webs are alternately provided with openings formed by different meshes in one direction, so that the regions A and B having different configurations are formed.
Are arranged in one direction to give a non-uniform pattern to the entire nonwoven fabric.

The non-woven fabric of the present invention is a laminated non-woven fabric in which a short-fiber non-woven web is arranged on at least one side of a long-fiber non-woven web layer. Since short fibers are used as constituent fibers, the surface area of the laminated non-woven fabric is , The biodegradation rate becomes faster. Further, since the long-fiber non-woven web and the short-fiber non-woven web are laminated and compounded by using the water jet punch method, the nonwoven fabric is highly flexible.

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EXAMPLES Next, the present invention will be specifically described based on Examples and Comparative Examples. The performance of the nonwoven fabric of the present invention was measured by the following method. (1) Unit weight of non-woven fabric: sample width 10 cm, sample length 10 c
Five sample pieces of m were prepared, their weights were measured, and the average value was taken as the basis weight (g / m ² ).

(2) Width of pattern: Area A of the obtained nonwoven fabric
And area B are measured at 10 points respectively, and the average value is displayed in mm.

(3) Opening area (mm ² ): Universal projector (manufactured by Nippon Kogaku Co., Ltd.) Model PROJECTOR V-
12, the lengths of 50 holes in each of the areas A and B in the vertical direction a and the horizontal direction b are measured in mm units with 3 digits after the decimal point, and a × b is calculated to calculate the average of the areas of 50 holes each. The value was defined as the open area. Even if a small amount of fiber was present in the aperture, it was determined that it was not present.

(4) Hole arrangement density (pieces / cm ² ): The number of holes in 1 cm ² was 10 using a universal projector manufactured by Nihon Kogaku Co., Ltd.
Counted over a number of places and averaged the distribution density (pieces / cm ² )
And

(5) Perforation area ratio: According to the measurement of the perforation area, the area of the perforation part is measured in the unit of mm in the vertical direction a and the horizontal direction b to 3 digits after the decimal point, and one open hole is measured. The vertical direction c and the horizontal direction d of the non-opened portion with respect to the part were measured in mm units, and calculated from the average value of 50 pieces by the following formula. (A × b) / (c × d) × 100 (6) Sharpness of pattern: ◎ Extremely clear. ○ It is clear. △ Somewhat clear. × It is unclear. The results visually evaluated by 10 panelists were evaluated according to the following four grades based on the total score.

(7) Microbial degradability A sample of 30 cm × 30 cm was buried in soil for 3 months and then taken out and visually observed to find that the sample lost its non-woven fabric form or retained its form. Even if the tensile strength was reduced to 50% or less of the initial value, the biodegradability was evaluated as good.

Example In the first step, a fluff rate of 88 was obtained by using fluff obtained from white knitted fabric having an average fineness of 1.7 denier and an average fiber length of 18 mm.
% Non-wool short fibers were used, and a random card machine was used to obtain a short fiber non-woven web having a random basis weight of 75 g / m ² .

Next, in the second step, the melting point is 116 ° C.,
Density 1.15 g / cc, melt flow rate 30 g / 1
A synthetic long fiber nonwoven web layer was produced by the spunbond method using 0 minutes polybutylene succinate. The non-woven web layer obtained had a monofilament fineness of 2.5 denier.
Then, the web thus obtained is subjected to a heat-pressure welding treatment to give a basis weight of 20.
A web layer of g / m ² was obtained. When performing the heat pressure welding process, an engraving pattern with an area of 0.36 mm ² has a pressure contact density of 40.
The point / cm ² and the linear pressure between both rolls were set to 10 kg / cm. Thereafter, the short fiber web and the long fiber web were laminated to obtain a laminated nonwoven web having a basis weight of 95 g / m ² .

Then, in a third step, the laminated nonwoven web was placed on a net mesh metallic porous support plate of the first stage high pressure liquid flow treatment shown in Table 1 which moved at 20 m / min, Injection holes for the high-pressure liquid flow at a position 50 mm above the laminated nonwoven web were 0.1 mm in hole diameter and 0.6 m in hole interval.
The first stage high-pressure liquid flow treatment was performed using an apparatus in which the orifice heads each having m injection holes arranged in m were arranged in five stages. That is, as the first preliminary entanglement, the preliminary entanglement is performed with water having a water pressure of 40 kg / cm ² G at room temperature,
Subsequently, as the second entanglement treatment, the entanglement treatment was performed four times with a water pressure of 70 kg / cm ² G using the net and the injection hole used for the preliminary entanglement. Further, as the third entanglement treatment, the same net and injection holes as above were used to reverse the entangled non-woven web, and 70 kg
A entanglement treatment was carried out 5 times with a water pressure of / cm ² G to obtain a laminated nonwoven web in which the front and back sides were entangled closely.

Subsequently, the obtained laminated nonwoven web was introduced onto a porous meshed net support plate for the high pressure liquid flow treatment of the second stage shown in Table 1, and as the injection holes of the high pressure liquid flow, the entanglement step was carried out. But with the injection hole at the orifice,
A high-pressure high-speed liquid stream with a water pressure of 50 kg / cm2, G was made to collide with the laminated nonwoven web by using a sheet in which narrowed portions and non-restricted portions were alternately arranged at mm intervals, and the second stage high-pressure liquid flow Treated. As the fourth step, the resulting laminated nonwoven web was subjected to a drying treatment by a drier after removing excess water with a mangle, and was subjected to an experiment No. Nonwoven fabrics 1 to 10 were obtained. The results of measuring the regions A and B of the obtained nonwoven fabric are shown in Table 1.
It was shown to.

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[Table 1]

Experiment No. Areas 1 to 2 and 9 are areas where small-area open holes are formed with a high arrangement density by the porous support plate of the first-stage high-pressure liquid flow treatment, and the fibers are three-dimensionally entangled in the non-open holes. And a large area of open holes is formed with a low arrangement density by the porous support plate of the second-stage high-pressure liquid flow treatment, and in the non-open hole portion, the inter-fibers are tertiary with a higher degree than in the non-open hole portion of the region. It was a laminated non-woven fabric in which regions which were originally entangled to have a dense structure were alternately arranged, and an extremely clear pattern was imparted due to the difference in the aperture shape. However, no. In No. 1, since the open area of the second-stage 8-mesh porous support plate was quite large, the morphological stability of the nonwoven fabric as a whole was slightly inferior.

Experiment No. Areas 3 and 8 are areas in which small-area open holes are formed with a high arrangement density by the porous support plate of the first-stage high-pressure liquid flow treatment, and the fibers are three-dimensionally entangled in the non-open holes. Large-area open holes are formed with a low arrangement density by the porous support plate of the second-stage high-pressure liquid flow treatment, and in the non-open holes, the fibers are three-dimensionally entangled to a higher degree than the non-open holes in the region. It was a laminated nonwoven fabric in which regions having a dense structure were alternately arranged and a clear pattern was provided due to the difference in the shape of the apertures.

Experiment No. In No. 4, open pores having a small area were formed in a high density on the entire surface, and fibers were three-dimensionally entangled in the non-opened portion, and the unidirectional pattern was unclear. That is, after applying the pattern with 70 mesh, 8
Although the pattern with 0 mesh was partially applied, the pattern with 70 mesh remained on the surface of the non-woven fabric because the mesh used was finer than that used for the high pressure liquid flow treatment in the 1st step. No fiber bundle re-arrangement due to the high pressure liquid stream treatment of.

Experiment No. In No. 5, large-area open holes were formed at a low disposition density on the entire surface, and fibers were three-dimensionally entangled in the non-open holes, and the unidirectional pattern was unclear. That is, after applying the pattern with 16 meshes, 2
Although the pattern with 0 mesh was partially applied, the pattern with 20 mesh remained on the surface of the non-woven fabric because the mesh used was finer than that used for the high pressure liquid flow treatment in the 1st step. The fiber bundles were not rearranged by the high-pressure liquid stream treatment of.

Experiment No. Reference numerals 6 and 10 denote regions in which small-area open holes formed by the porous support plate in the first-stage high-pressure liquid flow treatment are formed with a high arrangement density, and fibers are three-dimensionally entangled in the non-open holes. Large-area open holes are formed with a low arrangement density by the porous support plate of the second-stage high-pressure liquid flow treatment, and in the non-open holes, the fibers are three-dimensionally entangled to a higher degree than the non-open holes in the region. Although the laminated non-woven fabric in which the regions for providing a dense structure are alternately arranged, the pattern due to the difference in the shape of the apertures was slightly clear.

Experiment No. In No. 7, the area of the 160 mesh porous support plate was unclear in the open holes, and the shape of each hole was unclear. Therefore, not only the pore area could not be measured, but the entanglement between the fibers was weak and the mechanical strength was weak. It was poor in practical use. This area A and large areas of open holes formed by a 20-mesh porous support plate are formed with a low arrangement density, and in the non-opened areas, fibers are highly three-dimensionally entangled to provide a dense structure. Was alternately arranged, and the laminated non-woven fabric was provided with an extremely clear pattern due to the difference in the aperture shape.

Experiment No. In the laminated non-woven fabrics 1 to 10, since the non-wool fibers are used on the single fiber non-woven fabric side, the unique Unryu-shaped pattern was expressed as the ground pattern due to the presence of the undisentangled fibers.

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EFFECTS OF THE INVENTION The nonwoven fabric of the present invention has pores of a small area formed by a fine porous support plate at a high disposition density at the time of entanglement treatment and three-dimensionally entangled between fibers in the non-opened portion. Area A and a large area of open pores formed by the coarser porous support plate used in the entanglement treatment are formed with a low disposition density, and in the non-opened area, the distance between the fibers is larger than that in the non-opened area of the area A. The region B, which is highly three-dimensionally entangled and has a dense structure, has a structure in which a zebra pattern is provided alternately in one direction in the nonwoven fabric. Therefore, since the regions A and B have different configurations, their functions are also contradictory, and a spunlaced nonwoven fabric having an uneven pattern can be obtained.

The non-woven fabric of the present invention is a laminated non-woven fabric in which a short-fiber non-woven web is arranged on at least one surface of a long-fiber non-woven web layer. , The biodegradation rate is fast. Also, using the water jet punch method,
Since the long fiber non-woven web and the short fiber non-woven web are laminated and integrated, a nonwoven fabric having high flexibility is obtained. Therefore, the non-woven fabric of the present invention can be used as a non-woven fabric useful for clothing, medical care, daily life materials, industrial materials, agricultural materials, daily necessities and the like.

Claims (7)

[Claims] 1. A non-woven fabric in which a biodegradable long fiber web layer is disposed on one surface of a biodegradable short fiber web layer and both webs are integrated, and a small area of openings is highly distributed. Area A formed with a high density and having three-dimensional entanglement between the fibers in the non-opened area, and a large area of open holes formed with a low arrangement density and the area A between the fibers in the non-opened area. The non-woven fabric with a zebra pattern is characterized in that regions B, which are three-dimensionally entangled to a degree higher than that of the non-opened part to provide a dense structure, are alternately provided in one direction in the non-woven fabric. . 2. A non-woven fabric in which a biodegradable long fiber web layer is disposed on one side of a biodegradable short fiber web layer and both webs are integrated, and which satisfies the following (1). In the non-opened area, the area A in which the fibers are three-dimensionally entangled with each other in the non-opened area and in the non-opened area between the fibers are the above-mentioned area A. A zebra-patterned non-woven fabric, characterized in that regions B, which are three-dimensionally entangled to a degree higher than that of the non-opened part to provide a dense structure, are alternately provided in one direction in the non-woven fabric. (1) In the following formula, X is the open area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), Z is the open area ratio (%), and the open area is 17 × 10 ^{−. 2} mm ² or less, a hole arrangement density of 350 holes / cm ² or more, and an open area ratio of 30 to 6
0% X × Y = Z (2) In the following formula, X is the opening area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), Z is the opening area (%),
The open area is 30 × 10 ^-2 mm ² or more, the hole arrangement density is 100 / cm ² or less, and the open area ratio is 30 to 70%.
And X × Y = Z 3. A non-woven fabric in which a biodegradable long fiber web layer is disposed on one side of a biodegradable short fiber web layer and both webs are integrated, and which satisfies the following (1). In the non-opened area, the area A in which the fibers are three-dimensionally entangled with each other in the non-opened area and in the non-opened area between the fibers are the above-mentioned area A. It is characterized in that regions B, which are three-dimensionally entangled to a degree higher than that of the non-apertured part and have a dense structure, are alternately provided in one direction in the nonwoven fabric so as to satisfy the following (3). Non-woven fabric with a zebra pattern. (1) In the following formula, X is the open area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), Z is the open area ratio (%), and the open area is 17 × 10 ^{−. 2} mm ² or less, a hole arrangement density of 350 holes / cm ² or more, and an open area ratio of 30 to 6
0% X × Y = Z (2) In the following formula, X is the open area (mm ² ), Y is the hole arrangement density (pieces / cm ² ), and Z is the open area ratio (%). Is 30 × 10 ^-2 mm ² or more, the hole arrangement density is 100 holes / cm ² or less, and the open area ratio is 30 to 7
0% X × Y = Z (3) Arrangement interval (A / B) between area A and area B (mm / m
m) 10 to 1000/10 to 1000. 4. The biodegradable short fibers are natural fibers, recycled fibers, and synthetic fiber short fibers made of a biodegradable thermoplastic polymer, and the biodegradable long fibers are biodegradable. The non-woven fabric according to any one of claims 1 to 3, which is a synthetic fiber made of a thermoplastic polymer. 5. The non-woven fabric according to claim 1, 2 or 3, wherein the biodegradable staple fibers are fluff. 6. A non-woven web in which a biodegradable long fiber web layer is arranged on one side of a biodegradable short fiber web layer is placed on a fine mesh porous support plate, and injection holes are formed. Is subjected to the first-stage high-pressure liquid flow treatment by using a high-pressure liquid flow injection device uniformly arranged in the width direction to form an opening at a portion corresponding to the opening of the mesh, and not open. A region in which injection holes are uniformly arranged in the width direction by imparting three-dimensional entanglement between the fibers present in the holes and integrating both web layers, and then placing them on a porous mesh porous support plate. The high-pressure liquid flow injection device having the high-pressure liquid flow injection device in which the nozzles and the regions where the injection holes are not provided are alternately arranged in the width direction, and corresponds to the openings of the mesh by performing the second-stage high-pressure liquid flow treatment. The openings of the first stage are formed between the fibers existing in the non-opened area while forming the openings in the area. A method for producing a non-woven fabric with a zebra pattern, which comprises a three-dimensional entanglement higher in degree than that obtained by a high-pressure liquid flow treatment to provide a dense structure. 7. The porous support plate of fine mesh is a porous support plate of 50 mesh or more, and the porous support plate of coarse mesh is a porous support plate of 25 mesh or less. A method for producing a nonwoven fabric having a zebra pattern as described above.