KR19980081186A - Flexible Spunbond Nonwovens - Google Patents

Abstract

The present invention uses a span bond nonwoven fabric which includes at least one layer of a continuous long fiber of thermoplastic resin and is partially thermally bonded, thereby increasing flexibility and bulk so that it can be suitably used for medical materials and sanitary materials. It is about providing a bond nonwoven.

A feature of the present invention is a span bond nonwoven fabric having a weight per unit area of 10 to 70 g / m ² , made by partially thermocompressing a thermoplastic resin fiber of circular cross section having an average fiber diameter in the range of 10 to 50 μm, and constitutes the nonwoven fabric. The non-crimped or crimped fiber is less than 3 / cm, the fiber of the non-thermally compressed portion is arc-shaped, and the shortest distance between the thermally compressed portions is 0.5 mm or more, and the thickness of the compressed portion (t1) and the thickness of the non-compressed portion (t2) The ratio t2 / t1 is 12 to 100, and the stiffness is 70 mm or less.

The span bonded nonwoven fabric of the present invention may be a laminated nonwoven fabric in which a melt flow nonwoven fabric is laminated on a span bonded nonwoven fabric or a laminated nonwoven fabric in which a melt flow nonwoven fabric is sandwiched between two layers of span bonded nonwoven fabric.

Description

Flexible Spunbond Nonwovens

The present invention relates to a flexible span bond nonwoven fabric, and more particularly, to use a span bond nonwoven fabric formed by partially thermally bonding a layer of one or more layers of continuous long fibers of a thermoplastic resin, thereby improving flexibility and bulkiness, The present invention relates to a flexible span bond nonwoven fabric suitable for use in medical materials, hygiene materials and the like.

Conventional span bond nonwoven fabrics include one or more layers made of continuous long fibers of thermoplastic resins such as polyester, polypropylene, nylon, and the like, and are made by partially heat bonding, for example, thermal embossing. As a characteristic of the thermal bond embossed span bond nonwoven fabric,

① It can be thin and high density, ② It is suitable for products with relatively small weight per unit area, ③ It is excellent in abrasion resistance and dimension stability, and ④ It lacks flexibility of heat embossing part. According to the above characteristics, the span bonded nonwoven fabric subjected to thermal embossing is mainly used for hygiene materials such as paper diapers and sanitary products, agricultural materials such as seedling box hanger curtains, wire coating materials, filters, household goods, packaging materials, etc. It is rarely used in medical materials, sorbent materials, and clothing materials that require flexibility or bulkiness.

The embossed span bond nonwoven fabric is particularly free from scattering and robust in strength, compared to other manufacturing methods such as needle punch and water punch, in terms of properties other than flexibility. Since the fall, and the emboss portion as well as the non-emboss portion is inferior in bulk properties, the field of use has been limited. However, the characteristics of the spun-bonded nonwoven fabric with no scattering and high strength in terms of strength are very important for applications in hygienic materials, medical materials, sorbent materials, and clothing material systems. The trend of the market demanding one thing is becoming more prominent.

As a nonwoven fabric which improves the flexibility of such a thermally embossed span bond nonwoven fabric, a bulky span bond nonwoven fabric has been proposed as a nonwoven fabric obtained by thermal embossing a nonwoven fabric made of crimped fibers while the fibers constituting the nonwoven fabric have a release cross section. (Japanese Patent Publication No. 4-29776)

However, in order to manufacture such a nonwoven fabric, there is a problem in terms of economic efficiency and work efficiency, for example, a nozzle having a release cross section must be used, and a process for crimping must be added.

In view of such a prior art, an object of the present invention is to provide a flexible span bonded nonwoven fabric having abundant flexibility, bulkiness, and good feel while maintaining the properties of a thermally bonded span bonded nonwoven fabric such as thermal embossing.

The flexible span bond nonwoven fabric of the present invention is characterized by using a span bond nonwoven fabric formed by partially thermally bonding a layer of one or more layers of a continuous long fiber of a thermoplastic resin, specifically an average fiber diameter. A 10 to 70 g / m ² span bond nonwoven fabric made by partially thermocompressing a thermoplastic resin fiber having a circular cross section in the range of 10 to 50 µm, wherein the fibers constituting the nonwoven fabric are non-crimped or crimped water. It is less than 3 / cm, the fiber of the non-thermal compression part is arc-shaped, the shortest distance between the thermal compression parts is 0.5 mm or more, and the ratio of the thickness of the compression part (t ₁ ) and the thickness of the non-compression part (t ₂ ) (t ₂ / t ₁ ) Is from 12 to 100, and the stiffness is 70mm or less based on the configuration.

1 is a schematic view of a crossflow airflow treatment apparatus for producing a nonwoven fabric of the present invention.

2 is a schematic view of a cross flow liquid processing apparatus for producing a nonwoven fabric of the present invention.

3 is a schematic view of a parallel flow airflow treatment apparatus for producing a nonwoven fabric of the present invention.

4 is a schematic view of a parallel flow type airflow treatment apparatus for producing a nonwoven fabric of the present invention.

※ Explanation of code

1 Crossflow type airflow processing unit 2 Spunbond nonwoven fabric

3 drive rolls 4 perforated plate

5 Filter 6 Compressor

7 heat exchanger 8 nozzles

9 suction box 10 vacuum pump

11 Winding rolls 21 Crossflow liquid handling unit

22 Gas-liquid Separator 23 Blower

24 dryer 25 high pressure pump

31 Parallel flow type airflow processing device 32 Airflow incident part

33 Air flow section 34 Air flow passage

35 High Speed Airflow Treatment Unit 36 Pre-Roll

37 Surface Sediment 38 Wind

39 High speed airflow 41 Parallel flow airflow processing unit

42 blowout generators 43 diffusion boxes

44 takeover rolls

MEANS TO SOLVE THE PROBLEM As a result of earnestly researching in order to solve the said subject, as a result of scrubbing by the impact by the airflow or the liquid within the range of melting | fusing point of a thermoplastic resin after 50 degreeC or more, it is processed into the span bond nonwoven fabric heat-embossed. By performing post-processing including the step, it was found that the characteristics of the heat-bonded spunbonded nonwoven fabric were maintained as it was, and the flexibility and bulkiness were provided, thus completing the present invention.

That is, according to the present invention, the nonwoven fabric is a span bond nonwoven fabric having a weight per unit area of 10 to 70 g / m ² , which is formed by partially thermocompressing a thermoplastic resin fiber having a circular cross section having an average fiber diameter in the range of 10 to 50 μm. The non-crimped or crimped fibers are less than 3 / cm, the fibers of the non-thermally compressed portion are arc-shaped, and the shortest distance between the thermally compressed portions is at least 0.5 mm, the thickness of the compressed portion (t ₁ ) and the thickness of the non-compressed portion (t ₂ a) non (t ₂ / t ₁₎ is 12-100, the speech may be provided by a flexible span bond nonwoven fabric, characterized in that not more than 70mm.

Further, according to the present invention, a span bond nonwoven fabric having a weight of 5 to 50 g / m ² per unit area of thermoplastic fiber having a circular cross section having an average fiber diameter in the range of 10 to 50 µm and having a non-crimped or crimped number of less than 3 / cm. A layer and a weight per unit area formed by laminating and partially thermocompressing a melt flow nonwoven layer having a weight of 5 to 50 g / m ² per unit area made of thermoplastic fibers having an average fiber diameter in the range of 0.5 to 8 μm. A laminated nonwoven fabric having a thickness of ˜70 g / m ² , at least the fibers of the non-thermally compressed portion of the span bonded nonwoven fabric are arc-shaped, the shortest distance between the thermally compressed portions is 0.5 mm or more, the thickness of the compressed portion (t ₁ ) and the thickness of the non-compressed portion (t ₂ A flexible span bond nonwoven fabric is provided, characterized by a ratio t ₂ / t ₁ ) of 12 to 100 and a stiffness of 70 mm or less.

Further, according to the present invention, a span bond nonwoven fabric having a weight of 5 to 40 g / m ² per unit area made of thermoplastic fibers having a circular cross section having an average fiber diameter in the range of 10 to 50 µm and having a non-crimped or crimped number of less than 3 / cm. The weight per unit area made by laminating and partially thermocompressing a melt flow nonwoven layer having a weight of 2-50 g / m ² per unit area of thermoplastic resin having an average fiber diameter in the range of 0.5 to 8 μm between two layers. A laminated nonwoven fabric having a thickness of ¹² to 100 g / m ² , wherein at least the fibers of the non-thermally compressed portion of the span bonded nonwoven fabric are arc-shaped, the shortest distance between the thermally compressed portions is 0.5 mm or more, and the thickness (t ₁ ) of the compressed portion and the thickness of the non-compressed portion ( and t ₂₎ ratio (t ₂ / t ₁₎ of 12-100, the speech is also provided with a flexible span bond nonwoven fabric, characterized in that not more than 70mm.

According to the present invention, the above-mentioned partially spun bonded nonwoven fabric is a flexible spanboard nonwoven fabric which has been processed at a temperature of 50 ° C. or higher and including a scrub process accompanied by impacts by air flow or liquids below the melting point of the thermoplastic resin as a material. Is provided.

As a thermoplastic resin used for the raw material of the span bond nonwoven fabric of this invention, polyolefin, such as polyethylene, a polypropylene, and a polybutene, polyester, nylon, a polystyrene, etc. can be illustrated. Especially, polypropylene which is easy to obtain and has good radioactivity is more preferable. Polyolefins such as polyethylene and polypropylene may be produced by a polymerization method using a conventional catalyst such as a Ziegler catalyst. However, the one produced by a polymerization method using a single-site catalyst represented by a metallocene catalyst is more radioactive. Because of this superiority, not only the production cost can be reduced, but also the fiber diameter can be made thinner, and the rigidity of the resulting span bond nonwoven fabric can be reduced.

In this way, there is an advantage that the tensile strength can be made larger at the same fiber diameter.

And a span bond nonwoven fabric makes continuous long fibers from these materials, and forms the layer from these continuous long fibers. This layer is not limited to one layer but may be a plurality of two or more layers. Moreover, in the span bond nonwoven fabric which consists of several layers, the material of each layer may differ.

The fiber forming the span bond nonwoven fabric may be a single fiber made of a single thermoplastic resin or a core / super structure fiber composed of two or more kinds of thermoplastic resins having different melting points, but in the case of a core / super structure fiber, a concentric circle structure is preferable. .

Since a well-known thing can be used as it is as a manufacturing method of a span bond nonwoven fabric, detailed description is abbreviate | omitted.

The average fiber diameter of the span bond nonwoven fabric of this invention is 10-50 micrometers, Especially the thing of the range of 15-30 micrometers is used suitably. If it is less than 10 micrometers, intensity | strength will fall, and when it exceeds 50 micrometers, since flexibility and a texture tend to fall, it is unpreferable.

Moreover, the weight per unit area of this span bonded nonwoven fabric is suitably used in the range of 10 to 70 g / m ² , especially 15 to 60 g / m ² . If the weight per unit area is less than 10 g / m ^{2, the} strength decreases, and if it exceeds 70 g / m ² , the flexibility tends to be inferior.

In addition, the fibers constituting the nonwoven fabric used in the present invention has a non-crimped or crimped number of less than 3 / cm, and it is an important feature of the present invention that even a nonwoven fabric made of such fibers can provide a flexible span bond nonwoven fabric. Do.

The span bond nonwoven fabric of the present invention needs to be partially thermocompressed in order to have flexibility while maintaining the required strength, and the method includes a method of heating and pressing an embossed and mirror surface roll carved into an arbitrary pattern and thermocompressing therebetween. The method of thermocompression bonding using ultrasonic waves can be used.

At this time, the shortest distance between adjacent thermocompression bonding parts needs to be 0.5 mm or more, preferably 0.8 mm or more. If the distance is less than 0.5 mm, the fibers constituting the nonwoven fabric are excessively constrained to the nonwoven fabric surface, so that sufficient flexibility cannot be provided even by post processing.

Further, the fibers in the non-compression portion of the span bonded nonwoven fabric of the present invention form an arc shape, and the ratio (t2 / t1) of the thickness t1 of the compression portion to the thickness t2 of the non-compression portion is 12 to 100, preferably 15 It is -70. If the ratio is less than 12, it cannot be said to provide sufficient flexibility and bulkiness. On the contrary, if the ratio exceeds 100, the flexibility and bulkiness is excessive, resulting in an advantage as a partially bonded thermal bond nonwoven fabric such as high strength. To lose.

Moreover, the stiffness of the span bond nonwoven fabric of this invention is 70 mm or less.

If the stiffness exceeds 70 mm, the flexibility is lost, making it unsuitable for applications such as sanitary materials and medical materials.

Another aspect of the span bonded nonwoven fabric of the present invention is a composite nonwoven fabric in which a span bonded nonwoven fabric and a melt flow nonwoven fabric are laminated. The average fiber diameter of the said span bond nonwoven fabric layer is suitable in the range of 10-50 micrometers, especially 15-30 micrometers, The intensity | strength falls below 10 micrometers, and when it exceeds 50 micrometers, it exists in the tendency for a softness and a touch. In addition the weight per unit area of a span-bonded nonwoven fabric is suitably used is the 5~50g / m ^2, in particular 5~40g / m ^2.

If the weight per unit area of the span bonded nonwoven fabric is less than 5 g / m ² , the strength is lowered, and if it exceeds 50 g / m ² , the flexibility tends to be inferior. The fibers constituting the span bond nonwoven fabric have a non-crimped or crimped number of less than 3 / cm.

As a thermoplastic resin used as a raw material of a melt-flow nonwoven fabric, polyolefin, such as polyethylene, a polypropylene, polybutene, polyester, nylon, polystyrene, etc. can be illustrated. Especially, polypropylene which is easy to obtain and has good radioactivity is preferable. Polyolefins such as polyethylene and polypropylene may be produced by a polymerization method using a conventional catalyst such as a Ziegler catalyst. However, the one produced by a polymerization method using a single-site catalyst represented by a metallocene catalyst is more radioactive. Since this is excellent, not only can a production cost be reduced, but also a fiber diameter can be made thinner, and the rigidity of the obtained span bond nonwoven fabric can be reduced.

Accordingly, there is an advantage that the tensile strength can be made larger in the same fiber diameter.

And melt flow nonwoven fabric makes extremely fine fibers from these materials, and forms the layer by these extremely fine fibers. This layer is not limited to one layer, but may be two or more layers. Moreover, in the melt nonwoven fabric which consists of several layers, the material of each layer may differ. As a manufacturing method of a melt flow nonwoven fabric by itself, a well-known thing can be used as it is, detailed description is abbreviate | omitted.

The average fiber diameter of the melt flow nonwoven layer is 0.5-8 탆, particularly suitable in the range of 0.5-5 탆. If it is less than 0.5 micrometer, spinning is difficult, and when it exceeds 8 micrometers, there exists a tendency for inflexibility and a touch. In addition the weight per unit area of the nonwoven fabric is preferably a melt flow 5~50g / m ^2, in particular 5~30g / m ² range. If the weight is less than 5 g / m ^{2, the} strength decreases, and if it exceeds 30 g / m ² , the flexibility tends to be inferior.

In addition, the weight per unit area of the composite nonwoven fabric is preferably in the range of 10 to 70 g / m ² , in particular 20 to 60 g / m ² . If the weight per unit area is less than 10 g / m ^{2, the} strength decreases, and if it exceeds 70 g / m ² , the flexibility tends to be inferior.

The composite nonwoven fabric is partially thermally compressed after laminating a span bonded nonwoven fabric layer and a melt flow nonwoven fabric. The spunbonded nonwoven fabric before lamination may be one that is partially thermally compressed in advance.

Another aspect of the span bonded nonwoven fabric of the present invention is a composite nonwoven fabric obtained by sandwiching a melt flow nonwoven fabric between two layers of span bonded nonwoven fabric. The average fiber diameter of the span bond nonwoven layer is suitably used in the range of 10 to 50 µm, particularly 15 to 30 µm. If the said average fiber diameter is less than 10 micrometers, intensity | strength will fall, and when it exceeds 50 micrometers, it exists in the tendency for a softness | flexibility and a touch.

Moreover, the weight per unit area of the span bonded nonwoven fabric is preferably in the range of ^{5 to} 40 g / m ² , particularly in the range of ^{5 to 30} g / m ² . If the weight per unit area is less than 5 g / m ^{2, the} strength decreases, and if it exceeds 40 g / m ² , the flexibility tends to be inferior. In addition, the fiber which comprises the said span bond nonwoven fabric has a non-crimped or crimped number less than 3 piece / cm.

The average fiber diameter of the melt flow nonwoven fabric is suitably in the range from 0.5 to 8 μm, in particular from 0.5 to 5 μm. If the average fiber diameter is less than 0.5 µm, spinning is difficult, so it is difficult to manufacture at low cost, and if it exceeds 8 µm, there is a tendency for inflexibility and feel to be inferior.

Moreover, the weight per unit area of this melt flow nonwoven fabric is suitably used in the range of 2-50 g / m <^2> , especially the range of 2-30 g / m <^2> . If the weight per unit area is less than ² g / m ^{2, the} strength decreases, and if it exceeds 50 g / m ² , the flexibility tends to be inferior.

In addition, the weight per unit area of the composite nonwoven fabric is preferably used in the range of 12 to 100 g / m ² , especially 12 to 70 g / m ² . If the weight per unit area is less than 12 g / m ^{2, the} strength decreases, and if it exceeds 100 g / m ² , the flexibility tends to be inferior.

The post-processing of this invention includes the scrub process which consists of the impact by the airflow or the liquid of 50 degreeC or more and the melting | fusing point of the thermoplastic resin which is a raw material, the span bonded nonwoven fabric partially thermocompressed. If the temperature of the air flow or liquid is less than 50 ° C, the effect of softening is insufficient, and if the temperature exceeds the melting point of the thermoplastic resin as a raw material, the span bond nonwoven fabric melts and imparts flexibility and bulkiness.

The scrub process which consists of an impact of the airflow or liquids of this invention is performed by the crossflow type airflow processing apparatus 1 as shown, for example in FIG. This airflow treatment device 1 pressurizes the air cleaned by the filter 5 with the compressor 6, heats it with the heat exchanger 7, and blows it out intermittently or continuously from the injection port 8 with many thin holes. It consists of a high temperature, high pressure airflow generation | generation part, and the suction part which consists of the vacuum pump 10 of the suction box 9. As shown in FIG.

The span bond nonwoven fabric 2 is conveyed in the direction of the arrow A by the driving roll 3 and introduced into the high temperature and high pressure airflow generation portion, and is softened by the impact of the high temperature and high pressure airflow intermittently or continuously ejected from the injection port 8. The process is performed. The high temperature and high pressure airflow acts at an angle of at least 45 degrees, preferably approximately perpendicular to the span bond nonwoven, and is discharged out of the device from the suction through the perforated plate or mesh-shaped screen 4, the span bond nonwoven being driven roll It is wound up by the winding roll 11 by (3).

Although a suction part is not necessarily required, it is good to provide in order to make an airflow effect stronger. Moreover, it is more effective to provide a plurality of high-temperature, high-pressure airflow generation portions and suction portions, and to repeat the airflow treatment or to carry out airflow treatment from both sides of the span bond nonwoven fabric as shown in FIG.

Another aspect of the scrub process which consists of the impact by the airflow or liquid flow of this invention is performed with the crossflow type liquid flow processing apparatus 21 as shown in FIG. This liquid flow processing apparatus 21 pressurizes the liquid cleaned by the filter 5, generally water, with a high pressure pump 25, heats it with a heat exchanger 7, and has a plurality of fine holes 8 ), A high temperature and high pressure liquid flow generating part intermittently or continuously ejected from the filter, a suction part consisting of the suction box 9, the gas-liquid separator 22 and the vacuum pump 10, and the filter 5 to be cleaned and blower 23 ), And a dryer for introducing air heated by the heat exchanger (7) into the dryer (24).

The span bond nonwoven fabric 2 is introduced into the high temperature high pressure liquid flow generating portion by the driving roll 3, and the softening treatment is performed by the impact of the high temperature high pressure liquid flow intermittently or continuously ejected from the injection port 8. The high temperature and high pressure liquid flows through the gas-liquid separator 22 from the suction box 9 through the perforated plate or mesh-shaped screen 4 by acting at an angle of 45 degrees or more, preferably substantially perpendicular to the span bond nonwoven fabric. It is collect | recovered, it introduces again into the filter 5, and is used for circulation. The span bond nonwoven fabric is introduced into the dryer 24 by the driving roll 3 and dried, and then wound on the take-up roll 11.

Another aspect of the scrub process which consists of the impact by the airflow or liquid flow of this invention is performed by the parallel flow airflow processing apparatus 31 as shown in FIG. The airflow processing device includes a high speed airflow processing unit 35 and a fabric deposition unit 37. The high speed airflow processing unit 35 includes an airflow incidence unit 32 and an airflow passage 34 for generating high speed airflow; It consists of an airflow injection part 33. In addition, the high speed airflow processing part 35 and the cloth deposition part 37 arrange | position the drive roll 3 and the free roll 36 as shown in FIG. 3, and the processing fabric flow path forms the annular airflow 38 as a whole. . On the apparatus, ends of the fabric are connected to each other and are annular.

The span bond nonwoven fabric 2 which is softly processed is pressurized with the compressor 6 by the air cleaned by the filter 5, and the high temperature air stream heated by the heat exchanger 7 is passed through the air inlet 32 from the gas incidence part 32. 34, the airflow passage 34 is transported at high speed by the force of the high speed airflow 39, and an impact is applied.

Subsequently, the span bond nonwoven fabric 2 is conveyed to the fabric deposit via the drive roll 3 and stayed and compressed to undergo a scrub process. Subsequently, it is conveyed back to the high speed airflow processing part 35 via the pre-roll by the force of the high speed airflow mentioned above, and repeat processing is performed. In this processing apparatus, the internal temperature and the airflow temperature of the air freshness 38 are usually performed at a temperature of 50 ° C. or higher and below the melting point of the thermoplastic resin which is the raw material.

Another aspect of the scrub process which consists of the impact by the airflow or liquid flow of this invention is performed by the parallel flow type airflow processing apparatus 41 as shown in FIG. The airflow treatment device 41 pressurizes the air cleaned by the filter 5 with the compressor 6 and then heats it with the heat exchanger 7, for example, a high temperature such as an air-ejector. The low pressure part which consists of the jet flow generation part 42 and the diffusion box 43, and the take-up roll 44 is comprised.

The span bond nonwoven fabric 2 is introduced into the high temperature jet stream generator by the drive roll 3, and is ejected at high speed to the low pressure diffusion box together with the high temperature jet stream, and the softening treatment is performed by the impact at that time. The airflow is recovered, introduced into the filter 5 and circulated for use. The span bond nonwoven fabric is wound by the take-up roll 44 and wound on the winding roll 11. Preferably, as shown in Fig. 4, it is more effective to provide a plurality of units comprising a high temperature jet flow generator, a low pressure part made of a diffusion box, and a take-up roll and repeating the above operation.

(Example)

Hereinafter, the present invention will be described based on Examples.

However, this embodiment is intended to describe one preferred embodiment of the present invention, and is not limited thereto unless it exceeds the gist of the present invention.

The test of each physical property of an Example and a comparative example followed the following measuring method.

Melting point: DSC (differential calorimeter);

Melt flow: ASTM D1238 method (test temperature: 230 degreeC);

Weight per Unit Area: JIS L 1096

Thickness: visual measurement by electron microscopy (magnification 50x);

Tensile strength: JIS L 1096 A method (cut strip method);

Tear strength: JIS L 1096 A-1 method (single tang method);

Breathability: JIS L 1096 A method;

Water resistance: hydrostatic method of JIS L 1092 A method (low water pressure method);

Lecture degree: JIS L 1096 A method (45 degree cantilever method);

(Example 1, Comparative Example 1)

A spinneret with polypropylene (melting point Tm: 160 ° C., melt flow rate: 35 g / 10 min) as a raw material, supplied to an extruder and melt kneaded, having a hole diameter of 0.6 mm, and a spin hole of 756 holes Melt spinning was performed at a discharge amount of 0.66 g / min from each hole to form a filament having an average fiber diameter of 24 µm, and deposited on the collecting surface. This was formed with a span bond nonwoven fabric (area ratio of 18.3% of the hot pressing portion and the shortest distance of the hot pressing portion: 0.88 mm) partially thermally pressed by the heat embossing roll.

This nonwoven fabric was used as Comparative Example 1, and casting was then performed by the method shown in FIG. 3. The processing conditions were treated in the apparatus and at an air flow temperature of 120 ° C., a pressure of 0.3 MPa, and an air flow rate of 800 m / min and circulated 20 times. Various physical properties were measured about the span bond nonwoven fabric after this casting process, and the result is shown in Table 1.

(Example 2, Comparative Example 2)

Span bond / melt flow / each made of polypropylene (PP for span bonds; melting point Tm; 160 ° C., melt flow rate: 35 g / 10 min and melt flow PP; T m; 159 ° C., melt flow rate: 700 g / 10 min) The laminated nonwoven fabric which partially thermally crimped the three layers of the span bond by the heat embossing roll was created (area ratio of 17.5% of a thermal compression part, the shortest distance of a thermal compression part: 1.25mm).

The span bond nonwoven fabric layer was formed under the same conditions as in Example 1, and adjusted so that the weight per unit area was about 20 g / m ² . The melt flow nonwoven fabric layer was melt-spun from a spinneret with a hole diameter of 0.51 mmΦ and a hole number of 2130 holes at a discharge rate of 0.17 g / min per hole, and thinned with 1270 Nm ³ / h of hot air. A wave having an average fiber diameter of 3 μm was formed and adjusted to have a weight per unit area of about 20 g / m ² . Thus, the composite nonwoven fabric formed was made into the comparative example 2, and the said composite nonwoven fabric was processed on the conditions similar to Example 1. After the casting, various physical properties of the composite nonwoven fabric were measured and shown in FIG. 1.

And visual evaluation by electron micrograph showed that the fiber of the non-thermal-compression part of a span bond nonwoven fabric was linear in the comparative example (1, 2) of a non-flexible processed product, compared to the linear shape in the Example (1, 2) after flexible processing. It was an arc.

Evaluation Item 료 Sample Example 1 Example 2 Comparative Example 1 Comparative Example 2 Disc Composition * S fault S / M / S S fault S / M / S Weight (g / m ² ) 41.6 63.8 38.3 62.9 Thickness [mm] Uncompressed t ₂ 0.62 0.83 0.28 0.39 Compressor t ₁ 0.03 0.04 0.03 0.04 Thickness ratio (t ₂ / t ₁ ) 21 21 9 10 The tensile strength Strength [N / 5cm] horizontal 100 127 92 130 Vertical 54 37 57 33 horizontal 39 28 55 27 Elongation rate [%] Vertical 50 44 58 45 Tear strength [N] horizontal 16 16 14 15 Vertical 15 14 16 13 Breathability [cm ³ / cm ² s] 227 33 210 26 Water resistance [Pa] 1180 4510 1370 6380 Lecture width / length [mm] 56/40 63/34 97/53 86/42 * S: Spunbond nonwoven fabric M: Melt flow nonwoven fabric

As is apparent from Table 1, the span-bonded nonwoven fabric of the present invention has almost no change in tensile strength and tear strength as compared with Comparative Examples (1, 2), and has a low degree of decrease in water resistance indicating the shielding properties of the nonwoven fabric. It turns out that it is largely changing in a flexible direction, and the thickness which shows character is also quite thick.

According to the present invention, since the heat-bonded span bond nonwoven fabric is post-processed to have flexibility and bulk properties, the span bond nonwoven fabric has a high flexibility and a good bulk while maintaining the characteristics of the spun bond nonwoven fabric. Bond non-woven fabrics can be obtained, and various types of applications that have not been available until now, such as lack of flexibility, such as medical gowns and drapes, sanitary materials such as topsheets of paper diapers, packaging materials such as furnishings, tablecloths and cloths It is also used suitably for household goods, such as a wiper.

Claims (4)

Spunbonded nonwoven fabric having a weight per unit area of 10 to 70 g / m ² by partially thermocompressing a thermoplastic resin fiber of circular cross section having an average fiber diameter in the range of 10 to 50 µm, wherein the fibers constituting the nonwoven fabric are non-crimped. Or the number of crimps is less than 3 / cm, the fibers of the non-thermal compression part are arc-shaped, and the shortest distance between the thermal compression parts is 0.5 mm or more, and the ratio of the thickness (t ₁ ) of the compression part to the thickness (t ₂ ) A flexible span bond nonwoven fabric having a (t ₂ / t ₁ ) of 12 to 100 and a stiffness of 70 mm or less. Spunbond nonwoven fabric layer having a weight of 5-50 g / m ² per unit area of thermoplastic fiber having a circular cross section having an average fiber diameter in the range of 10 to 50 µm and a non-crimped or crimped number of less than 3 / cm, and an average 10 to 70 g / m weight per unit area, made by laminating and partially thermo-melting a melt flow nonwoven layer having a weight of 5 to 50 g / m ² per unit area of thermoplastic resin fibers having a fiber diameter in the range of 0.5 to 8 μm. ^A laminated nonwoven fabric of ² , wherein at least the fibers of the non-thermally compressed portion of the span bonded nonwoven fabric are arc-shaped, the shortest distance between the thermally compressed portions is at least 0.5 mm, and the ratio of the thickness (t ₁ ) of the compressed portion to the thickness (t ₂ ) of the non-compressed portion (t ₂ ) ₂ / t ₁ ) is 12 to 100, the stiffness is 70mm or less, flexible span bond nonwoven fabric. Between two layers of span bonded nonwoven layer having a weight of 5-40 g / m ² per unit area of thermoplastic fiber having a circular cross section having an average fiber diameter in the range of 10 to 50 µm and a non-crimped or crimped number of less than 3 / cm. Weight per unit area formed by laminating and partially thermocompressing a melt flow nonwoven layer having a weight of 2-50 g / m ² of thermoplastic resin having an average fiber diameter of 0.5 to 8 µm in average fiber diameter. A laminated nonwoven fabric having a thickness of ¹² to 100 g / m ² , wherein at least the fibers of the non-thermally compressed portion of the span bonded nonwoven fabric are arc-shaped, the shortest distance between the thermally compressed portions is 0.5 mm or more, and the thickness (t ₁ ) of the compressed portion and the thickness of the non-compressed portion ( t ₂₎ ratio (t ₂ / t is ₁₎ is 12-100, and presents also a flexible span bond nonwoven fabric, characterized in that not more than 70mm of. The method according to any one of claims 1 to 3, A flexible span bond nonwoven fabric having undergone post-processing, including a scrub step involving impacting the partially thermally compressed span bond nonwoven fabric by a flow of air or liquid at 50 ° C. or more and below the melting point of the thermoplastic resin as a material.