JP2002275750A - Laminated filament nonwoven fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conjugate filament nonwoven fabric having softness and tenacity and excellent weather resistance and chemical resistance. SOLUTION: A first layer of the nonwoven fabric is composed of the first constituent fiber produced by covering a core composed mainly of a propylene polymer with a sheath composed mainly of an ethylenic polymer. A second layer is composed of the second constituent fiber produced by covering a core composed mainly of an ester polymer with a sheath composed mainly of an ethylenic polymer. The first layer and the second layer are laminated and integrated to obtain the objective laminated filament nonwoven fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a laminated long-fiber nonwoven fabric.

[0002]

2. Description of the Related Art Nonwoven fabrics made of various thermoplastic polymers are used in various fields such as sanitary / medical materials, clothing materials, living materials, agricultural / horticultural materials, and the like. Among such nonwoven fabrics, polypropylene (hereinafter, “PP”)
Called. In the nonwoven fabric formed in (1), PP has excellent flexibility, weather resistance, and chemical resistance to sodium hydroxide and the like, so that the nonwoven fabric itself has flexibility, weather resistance, and chemical resistance. However, since PP is inferior in strength, there is a problem that sufficient nonwoven fabric strength cannot be obtained.

[0003] In addition, nonwoven fabrics formed of polyester typified by polyethylene terephthalate (hereinafter referred to as "PET") have strong dimensional stability and high strength, so that nonwoven fabrics also have high strength. Become. However, since PET has poor weather resistance and chemical resistance, it has a problem that it cannot be suitably used in fields such as agricultural and horticultural materials.

In order to obtain a non-woven fabric having both the flexibility and weather resistance of PP and the dimensional stability and strength of PET, a non-woven fabric made of PP and a non-woven fabric made of PET are laminated, and an adhesive is used. Adhesion is conceivable, but the resulting laminated nonwoven fabric is hardened by the adhesive, and the flexibility effect of PP cannot be obtained.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve such problems and to provide a long-fiber nonwoven fabric which has both flexibility and strength and is excellent in weather resistance and chemical resistance. And

[0006]

In order to achieve this object, a laminated long-fiber nonwoven fabric according to the present invention comprises a propylene polymer-based core portion surrounded by an ethylene-based sheath portion. A first layer formed of the covered first constituent fiber, and a second constituent fiber in which a periphery of a core mainly composed of a polyester-based polymer is covered with a sheath mainly composed of an ethylene-based polymer. Is a laminated long-fiber nonwoven fabric in which the second layer formed by the above is laminated and integrated.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The laminated long-fiber nonwoven fabric of the present invention is composed of a first constituent fiber in which a core composed mainly of a propylene polymer is covered with a sheath composed mainly of an ethylene polymer. A first layer formed and a second layer formed of second constituent fibers in which a core portion mainly composed of a polyester-based polymer is covered with a sheath mainly composed of an ethylene-based polymer. Are required to be laminated and integrated, and when applied to products, from the viewpoint of weather resistance, chemical resistance, etc., the first layer is placed on the outer side and the second layer is placed on the inner side. It is used by arranging it on the side.

As described above, the first layer composed of the first constituent fiber having the core of the propylene polymer having excellent flexibility, weather resistance and chemical resistance and the polyester polymer having excellent strength are used. By laminating and integrating the second layer made of the second constituent fiber as the core, a laminated long-fiber nonwoven fabric having both advantages of flexibility, weather resistance, chemical resistance and strength is obtained. Can be

The first layer is a polyolefin in which a core composed mainly of a propylene polymer is covered with a sheath composed mainly of an ethylene polymer having a melting point lower than the melting point of the propylene polymer. It is necessary to be formed of the first constituent fiber which is a core-sheath composite long fiber. The composite ratio of the sheath portion and the core portion of the first constituent fiber is preferably in a ratio of (sheath portion) :( core portion) = 15: 85 to 85:15 by mass ratio (% by mass). When the blending ratio of the ethylene-based polymer forming the sheath portion is less than 15% by mass, the adhesiveness between constituent fibers and the adhesiveness between the first layer and the second layer described later become inferior. When the blending ratio of the ethylene-based polymer that forms is more than 85% by mass, the blending ratio of the propylene-based polymer is too small, resulting in poor flexibility, weather resistance, and chemical resistance. Therefore, the composite ratio of the sheath and the core is expressed by mass ratio (mass%), (sheath) :( core) = 25 to 75:75.
More preferably in the range of from 25 to 25, and by mass ratio (% by mass), (sheath portion) :( core portion) = 35 to 65:65 to 35.
More preferably, it is within the range.

The polymer mainly composed of a propylene polymer forming the core of the first constituent fiber has a melting point higher than that of the ethylene polymer forming the sheath by 20 ° C. or more. Is preferred. As such a polymer, in addition to PP or a propylene-based polymer mainly composed of PP, ethylene or other higher α-olefin was copolymerized so as to be 10% by mass or less with respect to the propylene-based polymer. A PP copolymer can be used. In particular,
When the PP copolymer is used as the core, the adhesion between the ethylene polymer in the sheath and the propylene polymer in the core is improved, and the first layer and the second layer are laminated as described later. It is effective for improving the dimensional stability of the laminated long-fiber nonwoven fabric thus obtained.

The polymer mainly composed of an ethylene polymer forming the sheath of the first constituent fiber has a density of 0.9.
Low-density polyethylene (hereinafter referred to as “LDPE”) in the range of 10 to 0.930 g / cc, having a density of 0.930 to 0.930 g / cc.
Medium density polyethylene in the range of 0.942 g / cc (hereinafter referred to as “MDPE”), having a density of 0.842 g / c
c to 0.960 g / cc or less high-density polyethylene (hereinafter referred to as “HDPE”);
~ 14 α-olefin copolymerized density is 0.91
0 to 0.945 linear low density polyethylene (hereinafter referred to as "L
LDPE ". ) Can be preferably used. Also,
LLDPE obtained using a metallocene catalyst, which has recently attracted attention as a new material, may be used. Also in the case of LLDPE obtained from this metallocene catalyst, if the density is in the range of 0.910 or more and 0.94 or less, it is preferable because the yarn forming property is obtained.

The viscosity of these polyethylene materials is AS
The melt index measured by the method described in TM-D-1238E is preferably in the range of 15 to 50 g / 10 minutes. If the melt index is less than 15 g / 10 minutes, simply increasing the melting temperature will not improve the fluidity, and depending on the material, the fluidity will be reduced rather than the temperature rise, resulting in poor yarn-making properties. If the index exceeds 50 g / 10 minutes, the melt viscosity is too low and the fibers adhere to each other, so that a core-sheath type long fiber cannot be obtained.

In the second layer, the periphery of a core mainly composed of a polyester polymer is covered with a sheath mainly composed of an ethylene polymer whose melting point is lower than the melting point of the polyester polymer. It is necessary to be formed of the second constituent fiber which is a core-sheath composite long fiber. The composite ratio of the sheath portion and the core portion of the second constituent fiber is represented by mass ratio (mass%), and is (sheath portion) :( core portion).
= 15: 85 to 85:15. When the blending ratio of the ethylene polymer forming the sheath is 15
When the amount is less than 10% by mass, the adhesiveness between constituent fibers and the adhesiveness between a first layer and a second layer described later are inferior. If it is larger, the proportion of the polyester polymer is too small, resulting in poor strength and dimensional stability.
Therefore, the composite ratio of the sheath portion and the core portion is expressed by mass ratio (mass%),
(Shell) :( Core) = 25-75: More preferably in the range of 75-25, and by mass ratio (% by mass), (Shell) :( Core) = 35-65: 65-65. More preferably, the range is 35.

The polymer mainly composed of the polyester polymer forming the core of the second constituent fiber may have a melting point higher by at least 20 ° C. than the ethylene polymer forming the sheath. Preferably, PET is particularly preferably used. Also, the polymer may be copolymerized with other polymer components, and a polymer obtained by replacing part of terephthalic acid with isophthalic acid as an acid component for constituting the polymer may be used. You can also. In addition,
An aromatic polyester polymer, an aliphatic polyester polymer, or the like can be used. As the aromatic polyester polymer, for example, terephthalic acid, isophthalic acid,
An aromatic dicarboxylic acid such as naphthalene-2,6-dicarboxylic acid or an ester thereof is used as an acid component, and ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, cyclohexane-
A homopolyester polymer or polyester co-condensation polymer containing a diol compound such as 1,4-dimethanol as a glycol component can be used. Incidentally, these aromatic polyester polymers include paraoxybenzoic acid, 5-hydroxybenzoic acid,
Sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenol A and the like may be added or copolymerized.

As the polymer mainly composed of the ethylene polymer forming the sheath of the second constituent fiber, the same polymer as the ethylene polymer forming the sheath of the first constituent fiber is used. The same type of polyethylene polymer or a different type of polymer may be used as long as the first layer and the second layer can be used and the adhesion between the first layer and the second layer is not hindered. It is appropriately selected depending on the purpose and application of the laminated long-fiber nonwoven fabric.

[0016] The first layer and the second layer configured as described above are partially thermocompression bonded to each other by softening or melting the sheath of the first and second constituent fibers. Then, after the constituent fibers are integrated by being three-dimensionally entangled, they are partially thermocompression-bonded to form an integrated laminated long-fiber nonwoven fabric. This partial thermocompression bonding portion is formed by a known thermocompression treatment, and the three-dimensional confounding is formed by a known needle punching process or a spunlace process. Excellent mechanical strength and dimensional stability are exhibited in the nonwoven fabric.

The lamination ratio of the first layer and the second layer is not particularly limited, and may be appropriately selected depending on the purpose and application. (First layer / second layer) = 10/90 to 9 by mass ratio (% by mass)
It is preferable to laminate at a ratio of 0/10. When the proportion of the first layer is less than 10% by mass and the proportion of the second layer is more than 90% by mass, the flexibility is poor, and the weather resistance and the chemical resistance are also poor. On the other hand, the ratio of the first layer is 9
When the proportion of the second layer is more than 0% by mass and less than 10% by mass, the strength and the dimensional stability are inferior.

In the case where the first layer and the second layer are integrated by partial thermocompression bonding, the laminated first and second layers are subjected to partial thermocompression bonding. In this case, scattered crimping areas are formed between the long fibers due to softening or melting of the sheath. The shape of the crimping area may be any shape such as a round shape, an elliptical shape, a slit shape, a cross shape, a triangular shape, a square shape, a diamond shape, a T shape, a well shape, and the like. The ratio of the sum of the areas of the portions that are point-pressed to the entire area of the nonwoven fabric is referred to as the crimping area ratio, and the crimping area ratio of the nonwoven fabric in the present invention is preferably 4 to 40%. When the compression area ratio is smaller than 4%, the flexibility of the nonwoven fabric is improved, but the strength of the nonwoven fabric is reduced, and the shape retention of the nonwoven fabric is deteriorated.
If it exceeds 0%, the nonwoven fabric itself becomes extremely hard and is inferior in flexibility. Therefore, the crimping area ratio is more preferably in the range of 8 to 40%, further preferably 10 to 30%, and most preferably 10 to 20%.

The size of each crimping area is 0.1 to 1.
It is preferably about 0 mm ² . And individual crimping zone 0.1 mm ² smaller than lowered nonwoven strength,
Fluff is easily generated, and the individual crimping area is 1.0 m
If it is larger than m ² , the flexibility of the nonwoven fabric is undesirably reduced.

In the present invention, the existence of the pressure-bonded portion of the nonwoven fabric
The existing density is 4 to 40 pieces / cm^TwoPreferably about
Good. The density of the crimping part is 4 pieces / cm^TwoLess than non-woven
Increases fabric flexibility, but reduces nonwoven fabric strength and shape
Inferior in retention, and the density of the crimped part is 40 pieces / cm.
^TwoIf it exceeds, the nonwoven fabric itself becomes extremely hard and has poor flexibility.
Will be. Therefore, more preferably, the density of the crimped portion
Is 10-30 pieces / cm ^TwoIs good.

The laminated long-fiber nonwoven fabric of the present invention, which is laminated and integrated as described above, preferably has a compression stiffness as an index of flexibility of 4 cN / (g / m ² ) or less. In the present invention, it can be said that flexibility is good by setting the compression bristles to 4 cN / (g / m ² ) or less.

The basis weight of the laminated long-fiber nonwoven fabric is not particularly limited, and may be appropriately selected depending on the purpose and application.
The basis weight is preferably in the range of 10 to 150 g / m ² . When the basis weight is less than 10 g / m ² , the number of constituent fibers of the nonwoven fabric is too small, and the adhesiveness between the first layer and the second layer becomes poor. On the other hand, when the basis weight exceeds 150 g / m ² , the number of constituent fibers of the nonwoven fabric is too large, the rigidity is increased, and the flexibility is poor. In addition, the cost of the long-fiber nonwoven fabric becomes higher as the basis weight becomes higher, so that the practicality is inferior.

In the laminated long-fiber nonwoven fabric constructed as described above, the first constituent fibers constituting the first layer and the second constituent fibers constituting the second layer may be different depending on the use. It may be appropriately selected, and generally, the single yarn fineness of the first and second constituent fibers is preferably 2 to 10 dtex. Further, between the two layers, the single yarn fineness may be the same or different. In order to increase flexibility, by reducing the single yarn fineness of the second constituent fiber,
Further, in order to increase the strength, an intended product can be obtained by increasing the single fiber fineness of the second constituent fiber.

The first constituent fiber and the second constituent fiber constituting the laminated long-fiber nonwoven fabric of the present invention may include a coloring agent, a matting agent, a weathering agent, a pigment, a flame retardant, if necessary. Various additives such as a deodorant, a light stabilizer, a heat stabilizer, an antioxidant, and a crystallization accelerator may be added as long as the object of the present invention is not impaired.

The fiber cross section of each of the first and second constituent fibers is not particularly limited as long as the core is covered by the sheath. The eccentric shape may be a round cross section, or a shape having a hollow portion in the core portion, or the core portion and / or the sheath portion may have an irregular shape. Thus, a laminated long-fiber nonwoven fabric having excellent bulkiness and even more flexibility can be obtained.

Hereinafter, a method for producing a laminated long-fiber nonwoven fabric according to the present invention will be described. First, a composite long fiber web for forming the first layer is manufactured by a spun bond method. In that case, the molten propylene polymer and ethylene polymer are individually weighed so that the propylene polymer forms the core and the ethylene polymer forms the sheath in the completed yarn. After that, the composite is prevented by using an ordinary core-sheath type composite ferrule. Subsequently, the spun conjugate fiber is cooled and solidified by a spraying device, then pulled by air soccer, opened by an opening device, and deposited on a moving conveyor net to form a long fiber web.

In the same manner as described above, a composite long-fiber web in which the polyester-based polymer forms the core portion and the ethylene-based polymer forms the second layer forming the sheath portion is formed by a spunbond method.

In the method of the present invention, it is desirable to pull the fiber yarn by air soccer as high a spinning speed as possible within a range in which yarn breakage does not occur. By doing so, it is possible to increase the orientation of the fibers, suppress the heat shrinkage, and improve the physical properties of the nonwoven fabric. That is, high spinning speed is preferable from the viewpoint of productivity, and
It is preferable from the viewpoint of increasing the degree of crystal orientation of the fiber, and the heat shrinkage property is also reduced, so that heat resistance and dimensional stability are also improved. Further, the strength of the nonwoven fabric is increased because the strength of the fiber itself is maintained. However, the spinning speed is 3000m
At a low spinning speed lower than about / min, the heat shrinkage of the fiber becomes extremely high, and the dimensional stability of the nonwoven fabric is reduced, and a rough feeling is generated.

Next, the first layer and the second layer are laminated,
The obtained laminated long-fiber nonwoven web is subjected to point compression by a partial thermocompression bonding apparatus, and then wound up by a winder to form a laminated long-fiber nonwoven fabric. As the partial thermocompression bonding apparatus, a known embossing machine or an ultrasonic fusion machine can be used.

The processing temperature when an embossing machine is applied is preferably 5 to 30 ° C. lower than the melting point of the sheath. If the processing temperature is higher than the above range, the nonwoven fabric is inferior in flexibility and has low tensile strength. Further, when the processing temperature is further increased, the long fiber web is taken up by an engraving roll or a smooth roll, and the operability deteriorates. When the processing temperature is lower than the melting point of the sheath by 30 ° C. or more, the long fiber web is not thermocompressed, and the shape retention of the nonwoven fabric is reduced. Further, when the processing temperature is lowered, the long fiber web is taken up by the engraving roll, resulting in poor operability. As described above, even when the processing temperature is lower than the melting point, the softening point of the sheath is within the range of the processing temperature, and the softening point of the engraving roll is 9 points.
By applying a linear pressure of 8 to 9800 N / cm,
It is in a state of being securely pressed.

Since the shape, size, and area of the compression point applied to the nonwoven fabric are determined by the engraving area and shape of the engraving roll, an engraving roll capable of obtaining the above-described range is appropriately selected.

[0032]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. The measurement of various physical properties in Examples and Comparative Examples was performed by the following methods. (1) Melting point (° C.): Measured at a heating rate of 20 ° C./min using a differential scanning calorimeter DSC-2 manufactured by Perkin Elmer, and gives the maximum value in the obtained melting endothermic curve. The temperature was taken as the melting point. (2) Melt index (g / 10 minutes): The fluidity of polyethylene (hereinafter, referred to as “PE”) was measured using ASTM-
It measured according to the method of D-1238 (E).
(Hereinafter, referred to as “MI”) (3) Melt flow rate (g / 10 minutes): The fluidity of PP was measured according to the method described in ASTM-D-1238 (L). (Hereinafter, referred to as “MFR”) (4) Relative viscosity of polyester polymer: a mixture of phenol and ethane tetrachloride in an equal weight is used as a solvent,
0.5 g of a sample was dissolved in cc, and the measurement was carried out by a standard method at a temperature of 20 ° C. (5) Compression stiffness (cN / (g / m ² )) of the nonwoven fabric: Five sample pieces each having a sample length of 10 cm and a sample width of 5 cm were prepared, and each sample piece was bent in the longitudinal direction to form a cylinder. Each end was joined as a state object, and five samples for compression bending hardness measurement were prepared. Next, for each measurement sample, a constant speed elongation type tensile tester (Tensilon, UTM-4 manufactured by Toyo Baldwin Co., Ltd.)
-1-100), and compressed at a compression speed of 5 cm / min.
The value obtained by dividing the average value of the obtained maximum load values (g) by the basis weight of the nonwoven fabric was defined as the compression bending resistance. (6) Weight of nonwoven fabric (g / m ² ): Ten samples of 10 cm long × 10 cm wide were prepared from a standard sample.
After reaching the equilibrium moisture, the weight (g) of each sample piece was weighed, and the average value of the obtained values was converted into unit area (m ² ) to obtain the basis weight. (7) Single-fiber fineness (decitex): The fiber diameter in a web state was measured with a 50-line microscope, and the average value of fineness determined by density correction was defined as the single-fiber fineness. (8) Tensile strength (N / 5 cm width) and tensile elongation (%) of the nonwoven fabric: A sample length of 20 cm and a sample width of 5 cm according to the strip method described in JIS-L-1096 (A).
10 specimens were prepared, and a constant speed elongation type tensile tester (Tensilon UTM- manufactured by Toyo Baldwin Co., Ltd.) was prepared for each sample.
Using 4-1-100), each sample piece was elongated in the longitudinal direction at a tensile speed of 10 cm / min. Then, the average value of the obtained load values at cutting (kg / 5 cm width) was defined as the tensile strength. The average value of the maximum elongation at that time was defined as the tensile elongation (%) of the nonwoven fabric. (9) Weather resistance: Irradiation was performed for 300 hours on a sunshine weather meter, and the following tensile product retention rate was evaluated as good if it was 50% or more.

Tensile product retention = tensile product after irradiation / tensile product before irradiation × 100 (%) Tensile product = tensile strength × tensile elongation (N / m ² ·%) Was prepared by a spun bond method.

First, in order to form the first layer, the density was 0.95 g / cc, the melting point was 130 ° C., and the MI was 25 g / 1.
0 minute high density polyethylene (HDPE) as the sheath component,
Density 0.91 g / cc, melting point 160 ° C, MFR 4
5 g / 10 minutes of a polypropylene (P
P) as a core component to melt both these polymers,
E and PP were spun from a core-sheath type composite spinneret under the condition of a mass ratio of 50/50% by mass. After the spun yarn is cooled, it is drawn and thinned by air soccer at a drawing speed of 3800 m / min, spread using a known spreader, collected and deposited on a moving collecting surface, and has a single fiber fineness of 3%. A long fiber web forming a first layer having a basis weight of 25 g / m ² was prepared by decitex.

HDPE used for the sheath of the first layer is used as the sheath component, and has a relative viscosity of 1.38 and a melting point of 260 ° C.
Of polyethylene terephthalate (PET) as a core component, and the drawing speed was 4000 m / min, except that the single-filament fineness was 3 dtex and the basis weight was 25 g / min.
A long fiber web forming a second layer of m ² was made.

After laminating the long fiber web forming the first layer and the long fiber web forming the second layer on the moving collecting surface, the laminated web is heated at a roll temperature of 124 ° C. The flat roll with a linear pressure of 294 N / cm and 16 point patterns /
does partial thermocompression bonding sculptures cm ² is passed through a thermocompression bonding apparatus comprising a embossing roll that has been subjected, a basis weight of 50 g / m ²
Was obtained.

Table 1 shows the physical properties and the like of the obtained laminated long-fiber nonwoven fabric.

[0038]

[Table 1] Example 2 In preparing a long-fiber web forming the first layer, H was used.
A long fiber web having a basis weight of 25 g / m ² was prepared in the same manner as in Example 1 except that the composite ratio of DPE and PP was 70/30% by mass in terms of mass ratio, and the traction speed was 4000 m / min.

Also, the basis weight was 25 g / m ^{2 in the same} manner as in Example 1 except that the composite ratio of HDPE and PET was 70/30% by mass and the traction speed was 4200 m / min.
The long fiber web which forms the 2nd layer of this was produced.

Other than that, a laminated long-fiber nonwoven fabric was prepared in the same manner as in Example 1. Table 1 shows the physical properties and the like of the obtained laminated nonwoven fabric. Example 3 In preparing a long fiber web for forming the first layer, the density was 0.94 g / cc, the melting point was 125 ° C., and the MI was 30 g.
A long fiber web having a basis weight of 25 g / m ² was prepared in the same manner as in Example 1 except that linear low-density polyethylene (LLDPE) was used as a sheath component, and the drawing speed was set at 4100 m / min.

The LLDPE used for the sheath of the first layer
Was used as the component of the sheath, and the second example having a basis weight of 25 g / m ² was prepared in the same manner as in Example 1 except that the traction speed was set to 4300 m / min.
The long fiber web which forms the layer of was obtained.

Then, the roll temperature of the flat roll is set to 1
A laminated nonwoven fabric was prepared in the same manner as in Example 1 except that the temperature was changed to 20 ° C. Table 1 shows the physical properties of the obtained laminated long-fiber nonwoven fabric.
Shown in Example 4 In preparing a long-fiber web forming the first layer, L
A long fiber web having a basis weight of 25 g / m ² was prepared in the same manner as in Example 1 except that a polymer in which LDPE was mixed with 10% by mass of PP used as a core was used as a sheath component, and the drawing speed was 4300 m / min. did.

Further, the PP used in Example 1 was used for LLDPE.
Was used as the sheath component, and a long fiber web having a basis weight of 25 g / m ² was prepared in the same manner as in Example 1 except that the pulling speed was set at 4500 m / min.

Then, the roll temperature of the flat roll is set to 1
A laminated nonwoven fabric was prepared in the same manner as in Example 1 except that the temperature was changed to 20 ° C. Table 1 shows the physical properties of the obtained laminated long-fiber nonwoven fabric.
Shown in

In Examples 1 to 4, the first layer formed of the first constituent fiber having the propylene polymer as the core and the ethylene polymer as the sheath, and the polyester polymer were used. Since the core portion and the second layer formed of the second constituent fiber having the ethylene-based polymer as the sheath portion are laminated and integrated, the flexibility is superior to a single-phase nonwoven fabric. At the same time, the HDPE disposed on the sheath portions of both the first layer and the second layer provided excellent chemical resistance and mechanical properties. In addition, by disposing the first layer on the sunlit surface and disposing the second layer on the back surface, a laminated nonwoven fabric excellent in weather resistance was obtained.

In particular, in Example 2, since the amount of the core portion was increased as compared with Example 1, a laminated nonwoven fabric which was slightly inferior in flexibility but more excellent in mechanical properties and weather resistance was obtained. Example 3 is a laminated nonwoven fabric of the first layer and the second layer in which LLDPE is disposed in the sheath portion, and therefore has a higher flexibility and chemical resistance than a single-phase nonwoven fabric as in Example 1. Thus, a laminated nonwoven fabric having excellent mechanical properties and weather resistance was obtained.

Example 4 is a laminated nonwoven fabric of a first layer and a second layer in which a polymer in which LLDP is mixed with PP is disposed in a sheath portion. A laminated nonwoven fabric having excellent chemical properties, mechanical properties, and weather resistance was obtained. Comparative Example 1 In the same manner as in Example 1 except that only the PP used in Example 1 was melted and spun out from a single-phase spinneret, and the drawing speed was set to 3800 m / min, the fineness of the single yarn was 3 dtex. A long fiber web having a basis weight of 50 g / m ² was prepared.

Then, the roll temperature of the flat roll is set to 1
A long-fiber nonwoven fabric was prepared in the same manner as in Example 1 except that the temperature was changed to 50 ° C. Table 1 shows the physical properties and the like of the obtained long-fiber nonwoven fabric. Comparative Example 2 Only the PET used in Example 1 was melted and spun out from a single-phase spinneret, and a single-fiber fineness was 3 decitex in the same manner as in Example 1 except that the drawing speed was changed to 4500 m / min. A long fiber web having a basis weight of 50 g / m ² was prepared.

Then, the roll temperature of the flat roll is set to 2
A long-fiber nonwoven fabric was prepared in the same manner as in Example 1 except that the temperature was changed to 45 ° C. Table 1 shows the physical properties and the like of the obtained long-fiber nonwoven fabric.

Comparative Example 1 was a PP single-phase long-fiber nonwoven fabric, and thus had poor flexibility and mechanical properties.
Comparative Example 2 is a PET single-phase type long-fiber nonwoven fabric,
It was inferior in flexibility, chemical resistance and weather resistance.

[0051]

As described above, according to the present invention, the first layer is made of the first constituent fiber whose core is made of a propylene polymer and whose sheath is made of an ethylene polymer.
The propylene polymer constituting the core imparts flexibility, weather resistance and chemical resistance to the nonwoven fabric. Further, the second layer is formed of a second constituent fiber whose core portion is made of a polyester-based polymer and whose sheath portion is made of an ethylene-based polymer, so that the non-woven fabric is made of the polyester-based polymer constituting the core portion. Power is given to By laminating and integrating the first layer and the second layer, a laminated long-fiber nonwoven fabric having both advantages of flexibility, chemical resistance, weather resistance, and strength can be obtained.

 ──────────────────────────────────────────────────続 き Continuing on the front page F term (reference) 4F100 AK04A AK04B AK05 AK07A AK41B AK42 BA02 BA32 DG04A DG04B DG06A DG06B DG15 DG20A DG20B EC03 EJ19 GB01 GB66 GB72 JB01 JK05 JK13 JL1 AY02BA04A04A04B DD01 DD05 DD14 DD21 4L047 AA14 AA21 AA27 AB03 BA08 CA02 CA05 CB01 CB10 CC01 CC03 CC15 EA10

Claims (3)

[Claims] A first layer formed of a first component fiber in which a periphery of a core mainly composed of a propylene-based polymer is covered with a sheath mainly composed of an ethylene-based polymer; A second layer formed of a second constituent fiber in which the periphery of a core mainly composed of a polymer is covered with a sheath mainly composed of an ethylene polymer is laminated and integrated. A laminated long-fiber nonwoven fabric characterized by the above. 2. The laminated long-fiber nonwoven fabric according to claim 1, wherein the first layer and the second layer are integrated by partial thermocompression of constituent fibers. 3. The laminated long-fiber nonwoven fabric according to claim 1, wherein the compression rigidity is 4 cN / (g / m ² ) or less.