KR102611319B1 - Process for producing polyolefin conjugate spinning fiber with high spinning property, bulkiness and softness - Google Patents

Abstract

The present invention relates to a method for producing polyolefin composite spun fibers, and specifically, to a method for producing polyolefin composite spun fibers with excellent spinning properties, bulkiness, and flexibility. The method for producing a polyolefin composite spun fiber according to the present invention uses a polypropylene-based resin as a first component and a mixture of polypropylene-based resin and low-density polyethylene-based resin as a second component, and the first and second components are By including the step of composite spinning, polyolefin composite fibers with excellent spinning properties, bulkiness, and flexibility can be manufactured, and thus can be usefully used to produce parallel-type, peanut-type, or eccentric-type composite spinning nonwoven fabric.

Description

Method for manufacturing polyolefin composite spun fiber with excellent spinning properties, bulkiness and flexibility {PROCESS FOR PRODUCING POLYOLEFIN CONJUGATE SPINNING FIBER WITH HIGH SPINNING PROPERTY, BULKINESS AND SOFTNESS}

The present invention relates to a method for producing polyolefin composite spun fibers, and specifically, to a method for producing polyolefin composite fibers with excellent spinning properties, bulkiness, and flexibility.

In relation to non-woven fabrics for sanitary products used as materials for baby diapers and sanitary pads, interest in non-woven fabrics that are soft and flexible and can satisfy consumers' wearing comfort is growing. They meet the strength properties required for conventional non-woven fabrics for sanitary products and have a soft touch. Nonwoven fabric manufacturing technology and material technology that can implement are required.

Traditionally, polypropylene has been widely used as a non-woven material due to its excellent strength and fiber spinning properties. However, to further improve the feel, bulkiness, and flexibility of existing polypropylene non-woven fabrics, high-density polyethylene or alpha olefin comonomer content is mainly added to polypropylene. Research has been conducted on producing non-woven fabrics by mixing 5% or more of polyolefin-based elastomer.

However, if the mixing ratio of high-density polypropylene or polyolefin-based elastomer with an olefin comonomer content of 5% or more mixed into polypropylene is less than 8%, it is difficult to provide improved touch, bulkiness, and flexibility to the nonwoven fabric, and the mixing ratio is 8%. If it is above this, radioactivity is significantly reduced, making it difficult to provide high-quality nonwoven fabric.

As a way to solve this problem, composite spun fibers are made by independently combining two polymers with different physical and chemical structures, that is, two polymers are combined side by side (parallel type, peanut type) on the cross-section of the fiber, or a single polymer is used. Research has been conducted to manufacture non-woven fabrics by spinning fibers in a form (core-sheath type, eccentric type) surrounding other polymers.

Parallel-type, peanut-type, eccentric-type, and core-sheath type composite fibers are polypropylene as the first component and polymers with different physical and chemical structures as the second component, or polypropylene compositions mixed with polypropylene and polymers with different physical and chemical structures. This is used.

In the case of parallel, peanut, and eccentric composite fibers, crimp is given to the fiber due to the difference in swelling power and thermal viscosity of the first and second components, and bulkiness can be improved when manufactured with non-woven fabric. there is. If the first component and the second component are the same as polypropylene, the bulkiness can be improved to a limited extent due to the difference in melting point and melt index.

In addition, in the case of core-sheath composite fibers, they are used to provide improved fiber strength compared to existing polypropylene single-spun fibers, or to obtain a special surface compared to polypropylene, and can be used to manufacture nonwoven fabrics with improved tactile feel.

However, because the chemical structures of the first component polypropylene and the second component polymer of parallel-type and peanut-type composite fibers are greatly different, if the two polymers are incompatible and the interconnection is insufficient, the physical structure during the fiber stretching process or post-processing process is insufficient. There is a problem where the fiber interface is separated by force.

Republic of Korea Patent Publication No. 10-2003-0052313 (published on June 27, 2003) relates to a parallel hollow composite spun nonwoven fabric, in which the first component is composed of high-density polyethylene, the second component is composed of polypropylene, and the porosity is A nonwoven fabric manufactured with 20-30% parallel hollow composite spun fiber is disclosed, but the first component, polyethylene, and the second component, polypropylene, have low compatibility, so physical force is applied to the fiber interface during the stretching process or post-processing process. There is a separate issue.

Republic of Korea Patent Publication No. 10-2012-0113896 (published on October 16, 2012) relates to a core-sheath composite spun nonwoven fabric, in which the core part is composed of a mixture of polypropylene and polyolefin-based elastomer, and the sheath ( The sheath portion is made of high-density polyethylene, and a method for manufacturing a non-woven fabric with improved tactile feel is disclosed. However, it is difficult to improve the bulkiness of the non-woven fabric and there is a problem in that the interface between the polypropylene composition and the polyethylene composite spun fiber is easily separated.

Republic of Korea Patent Publication No. 10-2003-0071869 (published on September 6, 2003) relates to a core-sheath type or parallel type composite spun nonwoven fabric, in which the first component is composed of polypropylene homopolymer, and the second component has an ethylene comonomer content. It is composed of 0~10% mole polypropylene ethylene random copolymer, and when measured by differential scanning calorimetry (DSC), the melting point of the first component polypropylene is at least 20℃ higher than the second component polypropylene random copolymer, and the first component and Although nonwoven fabrics are disclosed, characterized in that the component ratio of the second component polymer is 30/70 to 5/95, nonwoven materials with superior bulkiness and flexibility are commercially required.

Republic of Korea Patent Publication No. 10-2014-0065898 (published on May 30, 2014) relates to a parallel type, peanut type, and eccentric type composite spun nonwoven fabric. The first and second components are composed of polypropylene, and the first component and the second component are composed of polypropylene. A polypropylene composite spun nonwoven fabric having a bulkiness and a polypropylene melt index ratio (first component/second component) of the second component is 1.3 to 2.6 is disclosed. However, commercially, a nonwoven material with superior bulkiness and flexibility is disclosed. It is being demanded.

Japanese Patent Laid-Open No. 1993-033218 (published on February 9, 1993) relates to a parallel-type composite spun split fiber, in which the first component is composed of polypropylene, and the second component is composed of a mixed composition of polypropylene and polyethylene, A polyolefin-based split fiber is disclosed, which is characterized in that the first component and the second component are arranged in parallel so that the contact length is 0.95 to 1.10 times the fiber diameter, but a composition with improved bulkiness and flexibility is not disclosed. not.

Japanese Patent Laid-Open No. 2004-522868 (published on July 29, 2004) relates to a bonded layer type nonwoven fabric. The first component is composed of polypropylene, and the second component is polypropylene (core component) and polyethylene (sheath component). Although the nonwoven fabric is disclosed, the composition with improved bulkiness is not disclosed.

Republic of Korea Patent Publication No. 10-2012-0113896 Republic of Korea Patent Publication No. 10-2003-0071869 Republic of Korea Patent Publication No. 10-2003-0071869 Republic of Korea Patent Publication No. 10-2014-0065898 Japanese Patent Publication No. 1993-033218 Japanese Patent Publication No. 2004-522868

The present invention is intended to solve the above problems, using a polypropylene-based resin as the first component and a mixture of polypropylene-based resin and low-density polyethylene-based resin as the second component. The purpose is to provide a method for producing polyolefin composite fibers with excellent spinnability, bulkiness, and flexibility, including the step of composite spinning.

The present invention includes (a) a polypropylene-based resin as the first component, (b) 81 to 99% by weight of the polypropylene-based resin, and (c) 1 to 19% by weight of the low-density polyethylene-based resin as the second component. Thus, a method for producing a polyolefin composite fiber is provided including the step of composite spinning the first component and the second component through each nozzle.

In addition, the present invention provides a composite spun nonwoven fabric containing polyolefin composite fibers produced by the method of producing the polyolefin composite fibers.

The method for producing a polyolefin composite spun fiber according to the present invention uses a polypropylene-based resin as a first component and a mixture of polypropylene-based resin and low-density polyethylene-based resin as a second component, and the first and second components are By including the step of composite spinning, composite spun fibers with excellent spinning properties, bulkiness, and flexibility can be manufactured, so they can be usefully used to produce parallel-type, peanut-type, or eccentric-type composite spun nonwoven fabric.

Hereinafter, the present invention will be described in more detail.

In the present invention, when a part "includes" a certain component, this means that it may further include other components rather than excluding other components, unless specifically stated to the contrary.

<Polyolefin composite fiber manufacturing method>

One aspect of the present invention is,

(a) a polypropylene-based resin as the first component, (b) a mixture containing 81 to 99% by weight of a polypropylene-based resin and (c) 1 to 19% by weight of a low-density polyethylene-based resin as the second component, A method of producing a polyolefin composite fiber comprising the step of composite spinning the first component and the second component through each nozzle.

As used herein, the term "composite yarn" refers to a fiber formed by combining multiple extrudates on each fiber or filament resulting in two or more separate sections occupied by distinct polymer components along the entire length of the fiber or filament. Alternatively, it refers to manufacturing filaments, and the cross-section of the fibers can take various arrangements such as parallel (side-by-side), peanut-shaped, or eccentric.

(a) First component polypropylene resin

In the method for producing polyolefin composite fibers according to the present invention, the first component to be composite spun is polypropylene-based resin.

The first component polypropylene-based resin according to the present invention may preferably be a polypropylene-based homopolymer from the viewpoint that the strength or heat resistance of the fiber or nonwoven fabric is important. In addition, the first component polypropylene resin according to the present invention is preferably a propylene polymer copolymerized with propylene and an alpha-olefin having 2 to 20 carbon atoms at a content of 0.1 to 10 mol% from the viewpoint of importance on the flexibility of fibers or nonwoven fabrics. It may be, and more preferably, it may be a propylene polymer copolymerized with propylene and an alpha-olefin having 2 to 20 carbon atoms at a content of 2 to 7 mol%. Specifically, if the alpha-olefin content is above the above range, excellent flexibility is provided, and if the content is below the above range, a decrease in the fiber cooling rate during spinning is suppressed, resulting in excellent nonwoven web formation.

From the viewpoint of improving nonwoven fabric spinning workability, the first component polypropylene resin according to the present invention may preferably have a molecular weight of 100,000 to 250,000 g/mol, and more preferably 120,000 to 230,000 g/mol, Most preferably, it may be 140,000 to 200,000 g/mol. Specifically, if the molecular weight is above the above range, the mechanical properties of the nonwoven fabric are excellent, and if the molecular weight is below the above range, the spinning workability is excellent.

From the viewpoint of improving nonwoven fabric spinning workability, the first component polypropylene resin according to the present invention may preferably have a molecular weight distribution (Mw/Mn) of 5 or less, more preferably 3.5 or less, and most preferably It may be 3.0 or less. Specifically, if the molecular weight distribution is below the above range, swelling of the molten polymer at the die discharge port during fiber spinning is suppressed, thereby ensuring uniform spinning workability.

(b) Second component polypropylene resin

In the method for producing polyolefin composite fibers according to the present invention, the second component to be composite spun includes 81 to 99% by weight, preferably 85 to 95% by weight, of polypropylene resin. Specifically, if the content of the second component polypropylene-based resin is above the above range, spinning workability is excellent, and if the content is below the above range, the mixing ratio of the second component polyethylene-based resin is high, resulting in excellent melting with the first component polypropylene-based resin. A difference in tension is given.

The type, molecular weight, molecular weight distribution, etc. of the second component polypropylene resin according to the present invention are the same as described for the first component polypropylene resin.

(c) Second component low-density polyethylene-based resin

In the method for producing polyolefin composite fibers according to the present invention, the second component to be composite spun includes 1 to 19% by weight, preferably 5 to 15% by weight, of low-density polyethylene-based resin. Specifically, if the content of the second component low-density polyethylene-based resin is more than the above range, an excellent difference in melt tension is provided compared to the first component polypropylene-based resin, and if the content is less than the above range, spinning workability is excellent.

In the second component that is compositely spun in the method for producing polyolefin composite fibers according to the present invention, (b) polypropylene-based resin and (c) low-density polyethylene-based resin exist as a mixture, and the mixture is the first component ( a) It is distinguished from polypropylene-based resin.

The second component low-density polyethylene resin according to the present invention provides a difference in thermal properties between the mixture of the second component (b) and (c) and the first component (a) and is easy to maximize the difference in melt tension. , the density may preferably be 0.910 to 0.925 g/cm3, more preferably 0.910 to 0.920 g/cm3, and most preferably 0.910 to 0.916 g/cm3.

The second component low-density polyethylene resin according to the present invention provides a difference in thermal properties between the mixture of the second component (b) and (c) and the first component (a) and is easy to maximize the difference in melt tension. , the viscosity average molecular weight (Mz) may be preferably 400,000 to 700,000 g/mol, more preferably 500,000 to 700,000 g/mol, and most preferably 550,000 to 650,000 g/mol. Specifically, if the viscosity average molecular weight (Mz) is above the above range, an excellent difference in melt tension is provided, and if the viscosity average molecular weight (Mz) is below the above range, spinning workability is excellent.

(d) Third component low crystallinity polypropylene resin

In the method of producing polyolefin composite fibers according to the present invention, the second component to be composite spun is preferably low crystallinity with respect to a total of 100 parts by weight of components (b) and (c) from the viewpoint of improving the bulkiness and flexibility of the nonwoven fabric. Polypropylene-based resin may be further included as an additive to the second component. The low crystallinity polypropylene-based resin is preferably 1 to 9 parts by weight, more preferably 3 to 9 parts by weight, and most preferably 5 to 9 parts by weight, based on a total of 100 parts by weight of components (b) and (c). It can be included as a part. Specifically, if the content of the third component low-crystalline polypropylene-based resin is more than the above range, flexibility and bulkiness are improved, and if it is less than the above range, commercial efficiency is excellent.

The third component low crystallinity polypropylene-based resin according to the present invention may preferably be polymerized under a metallocene-based catalyst.

The third component low crystallinity polypropylene-based resin according to the present invention may preferably be a propylene homopolymer. In addition, the third component low crystallinity polypropylene-based resin according to the present invention may preferably be a propylene polymer copolymerized with propylene and an alpha-olefin having 2 to 20 carbon atoms in an amount of 5 mol% or less. Specifically, when the content of alpha-olefin is less than the above range, spinning workability is excellent due to compatibility with the second component polypropylene resin.

The third component low crystallinity polypropylene-based resin according to the present invention may preferably have an isotacticity (Pentad I.I, mmmm) value of 20 to 70%, and more preferably 20 to 60%. , most preferably 30 to 60%. Specifically, the general isotactic polypropylene resin has a [mmmm] value of 95% or more. Due to its high crystallinity, the non-woven fabric has excellent non-woven fabric strength, but there is a problem in that the flexibility is reduced, and the general atactic polypropylene It has a [mmmm] value of less than 10%, but its crystallinity is very low, so its mechanical properties are significantly low, it is easily deformed, and it is sticky, making it difficult to use as a non-woven fabric. Therefore, if the stereoregularity of the third component low-crystalline polypropylene-based resin according to the present invention is above the above range, the adhesion is lowered to provide an excellent soft touch to the nonwoven fabric, and if it is below the above range, excellent flexibility is provided in terms of physical properties of the nonwoven fabric. .

The third component low-crystalline polypropylene-based resin according to the present invention may preferably have a molecular weight of 100,000 to 250,000 g/mol, and more preferably 120,000 to 230,000 g/mol, from the viewpoint of improving nonwoven fabric spinning workability. It may be, and most preferably, it may be 140,000 to 200,000 g/mol.

The third component low-crystalline polypropylene-based resin according to the present invention may have a molecular weight distribution (Mw/Mn) of preferably 5 or less, more preferably 3.5 or less, from the viewpoint of improving nonwoven fabric spinning workability, and most preferably 3.5 or less. Preferably it may be 3.0 or less. Specifically, if the molecular weight distribution is below the above range, the expansion of the molten polymer at the die discharge port during fiber spinning is suppressed, thereby ensuring uniform spinning workability.

The polyolefin composite fiber produced by the method of producing the polyolefin composite fiber according to the present invention is composite spun in parallel under the conditions of 5 denier (g/9000m) and spinning speed of 2,400 m/min, and preferably exhibits yarn shaking during 1 hour of work. This may not occur and there may be no single yarn occurrence.

In addition, the polyolefin composite fiber produced by the method of producing the polyolefin composite fiber according to the present invention has a desirable degree of crimp generation when 90 cm of filament yarn produced by spinning in a parallel composite spinning molding machine is heat treated at 100°C for 5 min. Preferably, the filament yarn apparent length may be less than 87 cm, more preferably, the filament yarn apparent length may be less than 84 cm, and most preferably, the filament yarn apparent length may be less than 81 cm.

In addition, the polyolefin composite fiber produced by the method of producing the polyolefin composite fiber according to the present invention has a flexural modulus measured according to the ASTM D790 method, preferably less than 16,000 kgf/cm2, more preferably less than 15,000 kgf/cm2, and most preferably less than 15,000 kgf/cm2. Preferably it may be less than 14,000 kgf/cm2.

Polyolefin composite fibers manufactured by the method of producing polyolefin composite fibers according to the present invention may not experience fiber interface separation during the stretching process or post-processing process.

Terms or words used in this specification and claims should not be construed as limited to their common or dictionary meanings, and the inventor may appropriately define the concept of terms in order to explain his or her invention in the best way. Based on the principle that there is, it must be interpreted with a meaning and concept consistent with the technical idea of the present invention. Therefore, it should be understood that the parallel, peanut, and eccentric composite spinning methods do not represent the entire technical idea of the present invention, and that there are various equivalents and modifications that can replace them depending on the cross-section of the yarn.

<Composite yarn non-woven fabric>

Another aspect of the present invention is a composite spun nonwoven fabric containing polyolefin composite fibers produced by the method for producing polyolefin composite fibers according to the present invention.

Manufacturing of the composite spun nonwoven fabric according to the present invention can be performed through a typical staple fiber process and a spunbond process, for example, by melt spinning and stretching the polyolefin-based resin composition for composite spinning to produce filament fibers of a predetermined thickness. It can be manufactured by web-lamination and heat-sealing or needle-punching the laminated filament web.

The composite spun nonwoven fabric according to the present invention may preferably have a fineness of 1 to 5 denier (g/9000m).

The basis weight of the composite spun nonwoven fabric according to the present invention may preferably be 8 to 80 g/m2.

Hereinafter, examples will be given in detail to explain the present specification in detail. However, the embodiments according to the present specification may be modified into various other forms, and the scope of the present specification is not to be construed as being limited to the embodiments described in detail below. The embodiments of this specification are provided to more completely explain the present specification to those with average knowledge in the art. In addition, "%" and "part" indicating content below are based on weight, unless otherwise specified.

Examples and Comparative Examples: Production of polyolefin composite fibers

The compositions of Examples 1 to 4 and Comparative Examples 1 to 3 were prepared with the composition and content of the ingredients shown in Table 1 below. Specifically, the composition of the first component or the second component was sufficiently mixed in a Henschel mixer at 800 rpm for 7 minutes, and then pellet-shaped polyolefin was produced using a 40 mm single-screw extruder with an L/D of 35 at a processing temperature of 180 to 230°C. A system resin composition was prepared. At this time, in Example 2, Example 4, and Comparative Example 3, a third component was added as an additive to the second component, and the content of the third component was mixed based on parts by weight of the second component. Afterwards, the prepared first component and second component pellet-shaped resin compositions were spun into a parallel composite spinning molding machine to produce filaments.

Classification (unit: parts by weight) Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative example 2 Comparative example 3 first ingredient (a) Polypropylene-based
profit 100 100 100 100 100 100 100 2nd ingredient (b) Polypropylene-based
profit 95 95 90 90 100 80 90 (c) low density
polyethylene resin 5 5 10 10 0 20 10 3rd ingredient (d) low crystallinity
polypropylene resin
(Based on a total of 100 parts by weight of the second component) 0 5 0 5 0 0 10

Experiment example

The composite fibers manufactured according to the above examples and comparative examples were evaluated by the following method, and the results are shown in Table 2 below.

[Assessment Methods]

1) Spinning: 5 denier (g/9000m), spinning speed 2,400m/min, parallel composite spinning, relative comparison of single yarn frequency and yarn vibration generated during 1 hour of work, A, B, C, D Evaluated in order.

A: No thread vibration occurs and no single yarn occurs.

B: No thread shaking occurs, but 1-2 single strands occur.

C: There is a slight thread shaking phenomenon, and 3-4 strands of single yarn are produced.

D: The thread tremor phenomenon is very severe, and more than 5 strands of single yarn are produced.

2) Bulkyness: When 90 cm of filament yarn was heat treated at 100°C for 5 min, it was evaluated in the order of A, B, C, and D according to the degree of crimp of the filament.

A: Filament yarn apparent length less than 81cm

B: Filament yarn apparent length ranging from 81cm to 84cm

C: Filament yarn apparent length ranging from 84cm to 87cm

D: Filament yarn apparent length of 87cm or more

3) Flexibility: Flexural modulus was measured according to ASTM D790 and evaluated in the order of A, B, C, D according to the degree of flexibility.

A: Flexural modulus of elasticity less than 14,000 kgf/㎠

B: Flexural modulus of elasticity in the range of 14,000 kgf/㎠ or more to less than 15,000 kgf/㎠

C: Flexural modulus in the range of 15,000 kgf/㎠ or more to less than 16,000 kgf/㎠

D: Flexural modulus of elasticity over 16,000 kgf/㎠

division Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative example 2 Comparative Example 3 characteristic radioactive A A A A A D D bulky B B A A D A A flexibility C B B A D A A

As a result, as shown in Table 2, a polyolefin-based resin containing the first component polypropylene-based resin, the second component polypropylene-based resin and low-density polyethylene-based resin, and the third component low-crystalline polypropylene resin in an optimal composition. It was found that the polyolefin composite fiber manufactured by composite spinning the resin composition had improved spinability, bulkiness, and flexibility.

Claims (11)

(a) a polypropylene-based resin as the first component, (b) a mixture containing 81 to 99% by weight of a polypropylene-based resin and (c) 1 to 19% by weight of a low-density polyethylene-based resin as the second component, A method of producing a polyolefin composite fiber comprising the step of composite spinning the first component and the second component through each nozzle to produce parallel, peanut-shaped, or eccentric fibers. According to paragraph 1,
The (a) polypropylene-based resin or (b) polypropylene-based resin is a propylene homopolymer or a propylene polymer copolymerized with propylene and an alpha-olefin having 2 to 20 carbon atoms at a content of 0.1 to 10 mol%, and has a weight average molecular weight. A method of producing polyolefin composite fibers, characterized in that the molecular weight distribution (Mw/Mn) is 100,000 to 250,000 g/mol and is 5 or less. According to paragraph 1,
(c) A method of producing a polyolefin composite fiber, characterized in that the low-density polyethylene resin has a density of 0.910 to 0.925 g/cm3 and a Z-average molecular weight of 400,000 to 700,000 g/mol. According to paragraph 1,
The mixture further comprises 1 to 9 parts by weight of low crystallinity polypropylene resin based on a total of 100 parts by weight of components (b) and (c). According to clause 4,
The low crystallinity polypropylene resin is polymerized with a metallocene catalyst, is a propylene homopolymer or a propylene polymer copolymerized with propylene and an alpha-olefin having 2 to 20 carbon atoms in an amount of 5 mol% or less, and has a stereoregularity of [mmmm] A method for producing polyolefin composite fibers, characterized in that the value is 20 to 70 mol% and the molecular weight distribution (Mw/Mn) is 5 or less. According to paragraph 1,
The polyolefin composite fiber produced by the method of producing the polyolefin composite fiber is spun in parallel in parallel under the conditions of 5 denier (g/9000m) and spinning speed of 2,400 m/min, so that no yarn vibration occurs and no single yarn is generated during 1 hour of work. A method of producing polyolefin composite fibers characterized by no. According to paragraph 1,
The polyolefin composite fiber produced by the method of producing the polyolefin composite fiber was heat-treated at 100°C and 5 min for 90 cm of filament yarn produced by spinning in a parallel composite spinning molding machine, and the degree of crimp occurrence was 87 cm in apparent length of the filament yarn. A method for producing polyolefin composite fibers, characterized in that less than. According to paragraph 1,
A method of producing a polyolefin composite fiber, characterized in that the polyolefin composite fiber produced by the method of producing the polyolefin composite fiber has a flexural modulus of less than 16,000 kgf/cm2 as measured according to the ASTM D790 method. According to paragraph 1,
A method of producing a polyolefin composite fiber, characterized in that fiber interface separation does not occur in the polyolefin composite fiber produced by the method of producing the polyolefin composite fiber during the stretching process or post-processing process. A composite spun nonwoven fabric comprising polyolefin composite fibers manufactured by the method of producing the polyolefin composite fiber of any one of claims 1 to 9. According to clause 10,
The composite spun nonwoven fabric has a fineness of 1 to 5 denier (g/9000m) and a basis weight of 8 to 80 g/m2.