JP6507442B2 - Fiber non-woven - Google Patents

Description

  The present invention relates to a fibrous nonwoven fabric using a polyolefin material.

  In recent years, polyolefin fibers and non-woven fabrics are used in various applications such as disposable diapers, sanitary products, hygiene products, clothing materials, bandages, packaging materials and the like. The fibers and non-woven fabrics are often used in applications in direct contact with the body, and in recent years, the required performance relating to good wearing feeling and touch feeling on the body has further increased. Therefore, with regard to non-woven fabrics, there is a need for technological development related to the improvement of texture for a good wearing feeling and the thinning of products for weight reduction.

  However, when manufacturing non-woven fabric by spun bonding method using polyolefin resin conventionally used, if single hole discharge amount is reduced or spinning speed is increased for thinning, yarn breakage occurs frequently And stable spinnability can not be obtained. When a thread breakage occurs, the broken fibers cause surrounding fibers to be wound to cause a roping phenomenon, and the non-woven fabric in the portion where the yarn breakage occurs or the portion where the roping fibers are dropped leads to defects and non-uniformness of the non-woven fabric. Lead to poor quality. For this reason, coexistence with the stable spinnability which yarn breakage does not generate | occur | produce, and the filamentation of a fiber is desired.

WO 2011/030893 brochure

Here, Patent Document 1 discloses a spunbond non-woven fabric using a resin composition containing low crystalline polypropylene and high crystalline polypropylene, but provides a non-woven fabric that is further excellent in flexibility and higher in strength. From the point of view, there is a demand for further thinning of the fibers constituting the non-woven fabric.
The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a fiber non-woven fabric using a polyolefin resin composition, in which fibers constituting the non-woven fabric are formed into filaments while maintaining spinning stability.

As a result of intensive studies, the present inventors have found that the use of a polyolefin resin composition having a specific crystallization rate solves the problem.
That is, the present invention
1. The fiber nonwoven fabric which consists of a resin composition (C) containing highly crystalline polyolefin (A) and low crystalline polyolefin (B) which satisfy | fill following conditions (1) and (2).
(1) half-crystallization time of highly crystalline polyolefin (A) (t _a) and the semi-crystallization time of the low crystalline polyolefin (B) (t _b) satisfies the relation of t _a <t _b.
(2) The half-crystallization time (t _c ) of the resin composition (C) is 1.2 to 2.0 times the half-crystallization time (t _a ) of the highly crystalline polyolefin (A).
2. The fiber non-woven fabric according to the above 1, wherein the fineness of the fibers constituting the fiber non-woven fabric is 0.2 to 1.3 deniers,
3. The fiber non-woven fabric according to the above 2, wherein the fineness of the fibers constituting the fiber non-woven fabric is 0.2 to 0.8 denier,
4. The initial elastic modulus of the high crystalline polyolefin (A) is 500 to 2,000 MPa, and the initial elastic modulus of the low crystalline polyolefin (B) is 5 MPa or more and less than 500 MPa Non-woven fabric, described
5. 6. The fiber non-woven fabric according to any one of the above 1 to 4, which is formed at a single-hole discharge rate of 0.1 to 0.5 g / min when forming the fiber non-woven fabric, and The spun bond nonwoven fabric comprised from the fiber whose fineness is 0.2-1.0 denier.
To provide

  ADVANTAGE OF THE INVENTION According to this invention, in the fiber nonwoven fabric using a polyolefin resin composition, the fiber which comprises a nonwoven fabric can be stringified, maintaining spinning stability.

<First invention>
The fiber nonwoven fabric of the first invention comprises a resin composition containing a high crystalline polyolefin (A) and a low crystalline polyolefin (B). In the present invention, the low crystalline polyolefin (B) refers to one having a longer half-crystallization time than the high crystalline polyolefin (A). In other words, half-crystallization time of highly crystalline polyolefin _(A) (t _a) and the semi-crystallization time of the low crystalline polyolefin (B) (t _b) satisfies the relation of t _a <t _b.

[Highly crystalline polyolefin (A)]
The type of the highly crystalline polyolefin (A) used in the first invention is not particularly limited as long as the condition (2) relating to the resin composition (C) described later can be satisfied, for example, polyethylene, propylene homopolymer Ethylene-propylene copolymer, ethylene-α-olefin copolymer, propylene-α-olefin copolymer, α-olefin homopolymer, copolymer of a plurality of α-olefins, etc. The olefin preferably has 4 to 24 carbon atoms, more preferably 4 to 12 carbon atoms, and particularly preferably 4 to 8 carbon atoms.

The initial modulus of elasticity of the high crystalline polyolefin (A) is preferably 500 to 2,000 MPa, more preferably 600 to 2,000 MPa, and still more preferably 700 to 1,800 MPa. The initial elastic modulus in the present specification is measured by the following measurement method.
[Measurement method of initial elastic modulus]
A 1 mm thick press sheet was made. From the obtained press sheet, the test piece according to JISK7113 (2002) -2 1/2 was sampled. Using an tensile tester (Autograph AG-I, manufactured by Shimadzu Corporation), set the initial length L0 to 40 mm, stretch at a tensile speed of 100 mm / min, and measure the strain and load in the stretching process, The initial elastic modulus was calculated from the following equation.
Initial modulus (N) = load 5% strain (N) /0.05

In the present specification, the half crystallization time (t _a , t _b and t _c ) indicates what is measured by the measurement method shown below.
[Method of measuring semi-crystallization time]
It measures by the following method using FLASH DSC (made by METTLER TOLEDO Co., Ltd.).
(1) The sample is heated to melt at 230 ° C. for 2 minutes and then cooled to 25 ° C. at 2000 ° C./sec, and the time change of the calorific value in the isothermal crystallization process at 25 ° C. is measured.
In the conventional DSC measurement, since the above-described rapid cooling was not possible, crystallization started in the cooling process, and accurate isothermal crystallization could not be evaluated around room temperature.
(2) Assuming that the integral value of the heat generation amount from the start of isothermal crystallization to the completion of crystallization is 100%, the time from the start of isothermal crystallization to the time when the integral value of heat generation becomes 50% is semicrystallization It was time.

[Low crystalline polyolefin (B)]
The type of the low crystalline polyolefin (B) is not particularly limited as long as the semicrystallization time is longer than that of the high crystalline polyolefin (A) as described above. For example, polyethylene, propylene homopolymer And ethylene-propylene copolymers, propylene-α-olefin copolymers, α-olefin homopolymers, copolymers of a plurality of α-olefins, etc. Are preferably, those having 4 to 12 carbon atoms are more preferable, and those having 4 to 8 carbon atoms are particularly preferable.

  The initial modulus of elasticity of the low crystalline polyolefin (B) is preferably 5 MPa or more and less than 500 MPa, more preferably 10 to 400 MPa, and still more preferably 20 to 300 MPa. The initial elastic modulus of the low crystalline polyolefin (B) can be measured in the same manner as the high crystalline polyolefin (A) described above.

When the high crystalline polyolefin (A) is a general-purpose polypropylene, as the low crystalline polyolefin (B), a low crystalline polypropylene satisfying the following (a) is preferable, and a low satisfying all the (a) to (f) Crystalline polypropylene is more preferred.
(A) [mm mm] = 20 to 60 mol%
The above low crystalline polypropylene has a [mm mm] (meso pentad fraction) of 20 to 60 mol%. If [mm mm] is 20 mol% or more, solidification after melting is quick, the stickiness of the fibers is suppressed, and adhesion to the winding roll is difficult, so continuous molding becomes easy. Moreover, since crystallinity degree falls that [mmmm] is 60 mol% or less, it is hard to produce a thread breakage, and also a nonwoven fabric with a soft touch feeling is obtained. From such a viewpoint, [mm mm] of the low crystalline polypropylene is more preferably 30 to 50 mol%, and still more preferably 40 to 50 mol%.

(B) [rrrr] / (1-[mm mm]) ≦ 0.1
The low crystalline polypropylene preferably has a [rrrr] / (1- [mm mm]) of 0.1 or less. [Rrrr] / (1- [mm mm]) is an index showing the uniformity of the regularity distribution of low crystalline polypropylene. When this value becomes smaller, it does not become a mixture of highly stereoregular polypropylene and atactic polypropylene as in conventional polypropylene manufactured using existing catalyst systems, and stickiness hardly occurs. From such a viewpoint, [rrrr] / (1- [mm mm]) of the low crystalline polypropylene is more preferably 0.05 or less, still more preferably 0.04 or less.

(C) [rmrm]> 2.5 mol%
The low crystalline polypropylene preferably has a [rmrm] (racemic mesoracemic mesopentad fraction) of greater than 2.5 mol%. When [rmrm] is 2.5 mol% or less, the randomness of the low crystalline polypropylene is reduced, the crystallization by the isotactic polypropylene block chain is increased, the degree of crystallinity is increased, the yarn is broken, and further, Soft touch feeling can not be obtained in the non-woven fabric. The [rmrm] of the low crystalline polypropylene is more preferably at least 2.6 mol%, further preferably at least 2.7 mol%. The upper limit is usually about 10 mol%.

(D) [mm] × [rr] / [mr] ² ≦ 2.0
The low crystalline polypropylene preferably has a [mm] (meso triad fraction) x [rr] (racemic triad fraction) / [mr] (meso racem triad fraction) ² of 2.0 or less. [Mm] × [rr] / [mr] ² is an index of polymer randomness, and the smaller the size is, the higher the randomness, the lower the thread breakage frequency, and the nonwoven fabric having a soft touch feeling is obtained. If this value is 2.0 or less, a non-woven fabric having a good soft touch feeling can be obtained without causing yarn breakage in the fibers obtained by spinning. From such a point of view, [mm] × [rr] / [mr] ² of the low crystalline polypropylene is more preferably more than 0.25 and not more than 1.8, and still more preferably 0.5 to 1.5. is there.

(E) Weight average molecular weight (Mw) = 10,000 to 200,000
The low crystalline polypropylene preferably has a weight average molecular weight of 10,000 to 200,000. When the weight average molecular weight is 10,000 or more, the viscosity of the low crystalline polypropylene is not too low and is adequate, so yarn breakage during spinning can be suppressed. When the weight average molecular weight is 200,000 or less, the viscosity of the low crystalline polypropylene is not too high, and the spinnability is improved. From such a viewpoint, the weight average molecular weight of the low crystalline polypropylene is more preferably 30,000 to 100,000, and still more preferably 40,000 to 80,000.

(F) Molecular weight distribution (Mw / Mn) <4.0
The low crystalline polypropylene used in the first invention preferably has a molecular weight distribution (Mw / Mn) of less than 4.0. When the molecular weight distribution is less than 4.0, the generation of stickiness in the fiber obtained by spinning is suppressed. The molecular weight distribution (Mw / Mn) of the low crystalline polypropylene is more preferably 3.0 or less, still more preferably 2.5 or less.

By using the low crystalline polypropylene which satisfy | fills said (a)-(f) with the above-mentioned general purpose polypropylene, the raw material suitable for manufacture of the nonwoven fabric of the objective which compensates the fault of general purpose polypropylene is obtained.
In addition, as low crystalline polypropylene which satisfy | fills said (a), as long as it can satisfy the conditions (2) regarding the resin composition (C) mentioned later, the copolymer using comonomers other than propylene may be sufficient. . In this case, the amount of comonomer is usually 2% by mass or less. As comonomers, ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene, 1-eikosen etc. are mentioned, In this invention, 1 type, or 2 or more types of these can be used.

[Resin composition (C)]
The resin composition (C) is a raw material of the fiber non-woven fabric of the first invention, contains the above-mentioned high crystalline polyolefin (A) and a low crystalline polyolefin (B), and is a semicrystal of the resin composition (C) The crystallization time (t _c ) is 1.2 to 2.0 times the half crystallization time (t _a ) of the highly crystalline polyolefin (A).
If the half-crystallization time (t _c ) is less than 1.2 times the half-crystallization time (t _a ), the crystallization rate of the resin composition (C) is fast, and from the nozzle during melt molding of the fiber Since the molten resin discharged immediately crystallizes, thread breakage easily occurs and thinning becomes difficult, and the fiber diameter is limited to 1.7 denier. On the other hand, if the half-crystallization time (t _c ) is more than 2.0 times the half-crystallization time (t _a ), the fiber surface becomes sticky and roping (a phenomenon in which the fibers stick to each other) occurs, which is stable It can not be spun, and the fibers become thick due to shrinkage, and also can not be thinned.
From the above point of view, the half-crystallization time (t _c ) is preferably 1.2 to 1.9 times and more preferably 1.3 to 1.9 times the half-crystallization time (t _a ) preferable.
Half-crystallization time of the resin composition (C) to (t _c), as a method for controlling the 1.2 times or more of the semi-crystallization time (t _a) of highly crystalline polyolefin (A) is highly crystalline polyolefin A method of increasing the proportion of the low crystalline polyolefin (B) in the combination of (A) and the low crystalline polyolefin (B), or the low crystalline polyolefin (B) in a half crystallization time (t _b ) There is a method to change to a long one. On the other hand, the resin composition (C) of the half-crystallization time (t _c), as a method for controlling the 2.0 times or less of the half-crystallization time (t _a) of highly crystalline polyolefin (A) is highly crystalline in the combination of sex polyolefin (a) and the low crystalline polyolefin (B), a method of reducing the ratio of the low crystalline polyolefin (B), the low crystalline polyolefin (B), more half-crystallization time (t _b The method of changing to a short thing of) is mentioned.

The content of the highly crystalline polyolefin (A) in the resin composition (C) is not particularly limited as long as the condition (2) relating to the resin composition (C) can be satisfied. In addition, the high crystalline polyolefin (A) and the low crystalline polyolefin (B) contents to satisfy the condition (2) for the resin composition (C) are the high crystalline polyolefin (A) and the low crystallinity. It depends on which type of polyolefin is selected in the polyolefin (B).
As an example, when the high crystalline polyolefin (A) is a general-purpose polypropylene and the low crystalline polyolefin (B) is a low crystalline polypropylene satisfying the above-mentioned initial elastic modulus, the high crystalline polyolefin in the above resin composition (C) ( The content of A) is preferably 50 to 98% by mass, and more preferably 60 to 95% by mass.
Further, the content of the low crystalline polyolefin (B) in the resin composition (C) is preferably 2 to 50% by mass, and more preferably 5 to 40% by mass.
Furthermore, the resin composition (C) has a content of low crystalline polypropylene satisfying the above-mentioned initial elastic modulus based on the total of the high crystalline polyolefin (A) and the low crystalline polyolefin (B). The content is preferably 35% by mass, and more preferably 5 to 30% by mass.

The said resin composition (C) may contain various additives, such as another thermoplastic resin and a mold release agent, as long as the said physical property is satisfy | filled.
Other thermoplastic resins include olefin polymers, and specifically, polypropylene, propylene-ethylene copolymer, propylene-ethylene-diene copolymer, polyethylene, ethylene / α-olefin copolymer, ethylene -A vinyl acetate copolymer, a hydrogenated styrene-type elastomer, etc. are mentioned. These may be used singly or in combination of two or more.

  The above-mentioned release agent refers to an additive for improving the releasability so that the formed non-woven fabric does not adhere to the roll or the conveyor of the forming machine. The mold release agent contained in a resin composition (C) is called an internal mold release agent, and an internal mold release agent means an additive for adding to a resin raw material and improving the releasability of a nonwoven fabric. The external mold release agent mentioned later means an additive for directly applying to a roll or a conveyor of a molding machine to improve the releasability of the non-woven fabric.

As the internal mold release agent, organic carboxylic acid or its metal salt, aromatic sulfonate or its metal salt, organic phosphoric acid compound or its metal salt, dibenzylidene sorbitol or its derivative, rosin acid partial metal salt, inorganic fine particles, Imido acids, amic acids, quinacridones, quinones or mixtures thereof may be mentioned.
Examples of the metal in the metal salt of the organic carboxylic acid include Li, Ca, Ba, Zu, Mg, Al, Pb and the like, and as the carboxylic acid, octylic acid, palmitic acid, lauric acid, stearic acid, behenic acid Fatty acids such as montanic acid, montanic acid, 12-hydroxystearic acid, oleic acid, isostearic acid, linosic acid, and aromatic acids such as benzoic acid and p-t-b-benzoic acid; specific examples thereof include benzoic acid Aluminum salts, aluminum salts of p-tert-butylbenzoic acid, sodium adipate, sodium thiophenecarboxylate, sodium pyrolecarboxylate and the like can be mentioned.
Specific examples of the above dibenzylidene sorbitol or derivatives thereof include dibenzylidene sorbitol, 1,3: 2,4-bis (o-3,4-dimethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-) 2,4-Dimethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-ethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-chlorobenzylidene) sorbitol and 1,3: 2,4-bis (o-4-chlorobenzylidene) sorbitol 2,4-dibenzylidene sorbitol and the like can be mentioned, and more specifically, Gelol MD and Gelol MD-R and the like manufactured by Shin Nippon Rika Co., Ltd. can be mentioned.
Examples of the rosin acid partial metal salt include Pine Crystal KM1600, Pine Crystal KM1500, Pine Crystal KM1300, and the like manufactured by Arakawa Chemical Industries, Ltd.
Examples of the inorganic fine particles include talc, clay, mica, asbestos, glass fibers, glass flakes, glass beads, calcium silicate, montmorillonite, bentonite, graphite, aluminum powder, alumina, silica, diatomaceous earth, titanium oxide, magnesium oxide, Pumice powder, pumice balloon, aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, dolomite, calcium sulfate, potassium titanate, barium sulfate, calcium sulfite, molybdenum sulfide and the like. In addition, as the silica, synthetic silica may be used, and examples include Silysia manufactured by Fuji Silysia Co., Ltd. and Mizukasil manufactured by Mizusawa Chemical Industry Co., Ltd.
Examples of the amide compound include erucic acid amide, oleic acid amide, stearic acid amide, behenic acid amide, ethylenebisstearic acid amide, ethylenebisoleic acid amide, stearylerucamide and oleylpalmitamide, adipic acid dianilide, suberic acid dianilide Etc.
Examples of the organic phosphoric acid metal salt include Adekastab NA-11 and Adekastab NA-21 manufactured by ADEKA Corporation.

These internal mold release agents can be used singly or in combination of two or more. In the present invention, among these internal mold release agents, erucic acid amide, dibenzylidene sorbitol, 1,3: 2,4-bis (o-3,4-dimethylbenzylidene) sorbitol, 1,3: 2,4. -Bis (o-2,4-dimethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-ethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-chlorobenzylidene) Preferred are those selected from sorbitol and 1,3: 2,4-dibenzylidene sorbitol.
In the resin composition (C), the content of the internal release agent is preferably 10 to 10000 mass ppm based on the resin mixture excluding the additive, and more preferably 100 to 5000 mass ppm. The function as a mold release agent is expressed as content of an internal mold release agent is 10 mass ppm or more, and the balance of the function as a mold release agent and economical efficiency becomes favorable as it is 10000 mass ppm or less.

  As various additives other than the mold release agent, conventionally known additives can be blended, and, for example, a foaming agent, a crystal nucleating agent, a flame resistance stabilizer, an ultraviolet light absorber, a light stabilizer, a heat stabilizer, antistatic Agents, flame retardants, synthetic oils, waxes, electrical property modifiers, anti-slip agents, anti-blocking agents, viscosity modifiers, color inhibitors, anti-fog agents, lubricants, pigments, dyes, plasticizers, softeners, aging Additives such as inhibitors, hydrochloric acid absorbents, chlorine scavengers, antioxidants, antiblocking agents, etc. may be mentioned.

[Non-woven fabric]
The nonwoven fabric of the first invention is obtained by using the above-mentioned resin composition (C) as a raw material, and is preferably manufactured by a spun bond method. Usually, in the spun bonding method, melt-kneaded resin composition is spun, and drawn and opened to form continuous long fibers, and continuous continuous fibers are subsequently deposited on a moving collection surface in a continuous process, and entangled. The nonwoven fabric is manufactured by combining. The method can continuously produce a non-woven fabric, and has high strength because the fibers constituting the non-woven fabric are continuous long fibers drawn.
A conventionally known method can be adopted as a spunbond method for producing the fiber non-woven fabric of the first invention, for example, from a large nozzle having several thousands of holes or a small nozzle group having for example about 40 holes. The fibers can be produced by extrusion of the molten polymer. After exiting the nozzle, the molten fibers are cooled by the crossflow cold air system, then pulled away from the nozzle and drawn by high velocity air. Usually, there are two air damping methods, both of which use the Venturi effect. The first method uses a suction slot to draw the filament (slot drawing), which is done with the width of the nozzle or the width of the machine. The second method draws the filament through a nozzle or suction gun. The filaments formed in this way are collected on a screen (wire) or on a pore forming belt to form a web. Next, the web passes through compression rolls, and then passes between heated calender rolls, and the raised portions on one roll bond at a portion including an area of about 10% to 40% of the web to form a non-woven fabric .

Hereinafter, specific conditions for producing a fiber non-woven fabric by the above-described spunbond method will be described.
[Manufacturing condition 1]
When manufacturing the fiber nonwoven fabric of the present invention with a spunbond nonwoven fabric molding machine using an ejector method, a fiber diameter of 1.0 can be obtained by using the above resin composition (C) according to a spunbond method under the following conditions. It can be thinned to the denier or less.
(1) Resin temperature: 200 ° C to 270 ° C
(2) Single hole discharge amount: 0.1 g / min to 0.5 g / min
(3) Ejector pressure: 1.0 kg / cm ^{2 to} 4.0 kg / cm ²
(4) Suction pressure: 600 rpm to 900 rpm
(5) Calendar temperature: 100 ° C to 150 ° C
(6) Nip pressure: 40 kg / cm

Under the above production condition 1, in the thinning of fibers, in particular, the following formula (1-1) between the single-hole discharge amount ([T] g / min) and the ejector pressure ([E] kg / cm ² ) It is preferable to set to the conditions which the relationship of-(1-4) is materialized.
[T] / [E] ≦ 0.25 (1-1)
[T] / [E] ≦ 0.2 (1-2)
[T] / [E] ≦ 0.13 (1-3)
[T] / [E] ≦ 0.1 (1-4)
If the [T] / [E] is 0.25 or less, the fibers of the obtained fiber non-woven fabric are likely to be fine yarns of 1.3 denier or less, and if 0.2 or less, the above fibers are 1.0 denier It is easy to become the following fine yarn, it is easy to become the fine yarn of 0.8 denier or less when it is 0.13 or less, and it is fine when the above fiber is 0.6 denier or less when it is 0.1 or less It is easy to become.

[Manufacturing condition 2]
In the case of producing the fiber nonwoven fabric of the first invention by a spun bond nonwoven fabric molding machine using a cabin system, a fiber diameter of 1. by using the above resin composition (C) by a spun bond method under the following conditions. It can be thinned to 0 denier or less.
(1) Resin temperature: 200 ° C to 270 ° C
(2) Single hole discharge amount: 0.3 g / min to 0.6 g / min
(3) Cabin pressure: 4500 Pa to 8000 Pa
(4) Calendar temperature: 100 ° C to 150 ° C
(5) Nip pressure: 100 N / mm

Under the above production condition 2, in the thinning of fibers, in particular, between the single-hole discharge amount ([T] g / min) and the cabin pressure ([C] Pa), the following formulas (2-1) to (2) It is preferable to set to the conditions which the relationship of- 3 is satisfied.
[T] / [C] × 1000 ≦ 0.09 ... (2-1)
[T] / [C] × 1000 ≦ 0.06 (2-2)
[T] / [C] × 1000 ≦ 0.05 (2-3)
When [T] / [C] × 1000 is equal to or less than 0.09, the fibers of the obtained fiber non-woven fabric are likely to become fine yarns of 1.3 denier or less, and when it is 0.06 or less, The fiber tends to be a fine yarn of 0 denier or less, and a fiber of 0.05 or less tends to be a fine yarn of 0.9 denier or less.

  In the case of using an external mold release agent when producing the fiber non-woven fabric of the first invention, the external mold release agent is dispersed on the movable collection surface. When the resin composition (C) contains an internal release agent, it is not necessary to disperse the external release agent on the moving collection surface, but from the viewpoint of obtaining good releasability, it is used in combination with the internal release agent. You may

Specific examples of the external release agent include fluorine-based release agents and silicone-based release agents. As a fluorine-type mold release agent, the free release by Daikin Industries, Ltd. and the release by Neos Co., Ltd. are mentioned. Examples of silicone-based mold release agents include SPRAY 200 manufactured by Toray Dow Corning Silicone Co., Ltd., KF 96 SP manufactured by Shin-Etsu Chemical Co., Ltd., EPOLIES 96 manufactured by Nippon Pelnox Co., Ltd., KURE-1046 manufactured by Sakai Industry Co., Ltd. Be These can be used singly or in combination of two or more. In the first invention, among these external release agents, silicone-based release agents are preferred.
As a method of spraying an external mold release agent on the said collection surface, the method by a spray etc. is mentioned.

  As a fiber product using the fiber nonwoven fabric of the first invention, the following fiber products can be mentioned, for example. That is, members for disposable diapers, stretchable members for diaper covers, stretchable members for sanitary products, stretchable members for hygiene products, stretchable tapes, plasters, stretchable members for clothes, insulating materials for clothes, heat-retaining materials for clothes, Protective clothing, hats, masks, gloves, supporters, elastic bandages, compress base, slip-proof base, vibration absorbers, fingersacs, clean room air filters, electret-treated electret filters, separators, heat insulators , Coffee bags, food packaging materials, ceiling materials for automobiles, soundproofing materials, cushioning materials, dustproof materials for speakers, air cleaners, insulators, skins for backings, backing materials, adhesive non-woven sheets, door trims, cleaning of various automobile members Cleaning materials such as wood, carpet front and back materials, agricultural distribution, wood drain Shoes for members, bag for members such as sports shoes skin, industrial sealing material, such as wiping material and sheets can be mentioned. The nonwoven fabric of the present invention is particularly preferably used for sanitary materials such as disposable diapers.

<Second invention>
The spunbonded nonwoven fabric according to the second invention has a fineness of 0.2 to 1.0 denier (preferably 0.2 to 0.8 denier, more preferably 0.2 to 0.6 denier, still more preferably 0.3). ~ 0.6 denier) is composed of fibers.
The details of the spunbonded nonwoven fabric according to the second invention are not limited to those composed of the resin composition (C) containing the above-mentioned high crystalline polyolefin (A) and low crystalline polyolefin (B), It is the same as the fiber non-woven fabric according to the first invention, and is suitably produced by the spun bond method (production condition 1) using the above-mentioned ejector method.

The following examples are described for illustrative purposes only and are non-limiting examples.
Example 1
(Preparation of resin composition)
10 parts by mass of low crystalline polypropylene (manufactured by Idemitsu Kosan Co., Ltd., “L-MODU (registered trademark) S901”, MFR: 50 g / 10 min, melting point: 70 ° C.), and highly crystalline polypropylene A (manufactured by Japan Polypropylene Corporation) A resin composition was prepared by adding 2000 ppm of erucic acid amide based on the resin mixture to a resin mixture consisting of 90 parts by mass of "NOVATEC SA-03", MFR: 30 g / 10 min, melting point: 160 ° C.
Physical properties of the low crystalline polypropylene and the high crystalline polypropylene A were measured by the measurement methods shown below. The results are shown in Table 1.

Initial modulus of elasticity
The polypropylene was press-molded to prepare a test piece, which was measured by a tensile test in accordance with JIS K-7113.
・ Test piece (No. 2 dumbbell) Thickness: 1 mm
・ Crosshead speed: 50mm / min
・ Load cell: 100 kg

[Semi-crystallization time]
The half crystallization time measured by the following method was used using FLASH DSC (manufactured by METTLER TOLEDO Co., Ltd.).
(1) The sample is heated to melt at 230 ° C. for 2 minutes and then cooled to 25 ° C. at 2000 ° C./sec, and the time change of the calorific value in the isothermal crystallization process at 25 ° C. is measured.
(2) Assuming that the integral value of the heat generation amount from the start of isothermal crystallization to the completion of crystallization is 100%, the time from the start of isothermal crystallization to the time when the integral value of heat generation becomes 50% is semicrystallization It was time.

[Melt flow rate (MFR)]
In accordance with JIS K7210, the measurement was performed under the conditions of a temperature of 230 ° C. and a weight of 21.18 N.

[Melting point]
A melting endotherm obtained by heating a sample at 10 ° C./min after holding 10 mg of the sample at −10 ° C. for 5 minutes in a nitrogen atmosphere using a differential scanning calorimeter (Perkin Elmer, DSC-7) The melting point (Tm-D) was determined from the peak top of the peak observed on the highest temperature side of the curve.

[Weight average molecular weight (Mw), molecular weight distribution (Mw / Mn) measurement]
The weight average molecular weight (Mw) and the molecular weight distribution (Mw / Mn) were determined by gel permeation chromatography (GPC). The following apparatus and conditions were used for the measurement, and the weight average molecular weight of polystyrene conversion was obtained.
<GPC measuring device>
Column: TOSO GMHHR-H (S) HT
Detector: RI detector for liquid chromatography WATERS 150C
<Measurement conditions>
Solvent: 1,2,4-Trichlorobenzene Measurement temperature: 145 ° C
Flow rate: 1.0 ml / min Sample concentration: 2.2 mg / ml
Injection volume: 160 μl
Calibration curve: Universal Calibration
Analysis program: HT-GPC (Ver. 1.0)

[NMR measurement]
The measurement of the ¹³ C-NMR spectrum was performed under the apparatus and conditions shown below. The peaks were assigned according to the method proposed by A. Zambelli et al. In "Macromolecules, 8, 687 (1975)".
Apparatus: JNM-EX400 type ¹³ C-NMR apparatus manufactured by Nippon Denshi Co., Ltd. Method: Proton complete decoupling method Concentration: 220 mg / ml
Solvent: 90:10 (volume ratio) mixed solvent of 1,2,4-trichlorobenzene and heavy benzene Temperature: 130 ° C.
Pulse width: 45 °
Pulse repetition time: 4 seconds Integration: 10000 times

<Calculation formula>
M = m / S × 100
R = γ / S × 100
S = Pββ + Pαβ + Pαγ
S: Signal strength of side chain methyl carbon atom of all propylene units Pββ: 19.8 to 22.5 ppm
Pαβ: 18.0 to 17.5 ppm
Pαγ: 17.5 to 17.1 ppm
γ: racemic pentad chain: 20.7 to 20.3 ppm
m: meso pentad chain: 21.7 to 22.5 ppm

The mesopentad fraction [mmmm], the racemic pentad fraction [rrrr] and the racemic mesoracemic mesopentad fraction [rmrm] are given by A. Zambelli et al. In “Macromolecules, 6, 925 (1973)”. Determined according to the proposed method, the meso fraction, racemic fraction and racemic mesoracemic mesomer at pentad units in the polypropylene molecular chain determined by the signal of the methyl group in the ¹³ C-NMR spectrum It is a fraction. As the mesopentad fraction [mmmm] increases, stereoregularity increases. The triad fractions [mm], [rr] and [mr] were also calculated by the above method.

  Moreover, also about the said resin composition, half crystallization time was measured by the above-mentioned measuring method. Furthermore, the value obtained by dividing the half crystallization time of the resin composition by the half crystallization time of the highly crystalline polypropylene was taken as the relative crystallization time ratio. The results are shown in Table 2.

(Production of non-woven fiber)
The resin composition is melted and extruded at a resin temperature of 250 ° C. using a single-screw extruder having a gear pump, and a single-hole discharge rate of 0.1 g / min from a nozzle with a nozzle diameter of 0.3 mm (hole number 841). The molten resin was discharged and spun. While cooling the fibers obtained by spinning with air, they were sucked by an ejector at a pressure of 1.0 kg / cm ² under the nozzles to laminate the fibers on the moving net surface at a line speed of 11 m / min. The fiber bundle laminated on the net surface was embossed at a nip pressure of 40 N / mm with a calender roll heated to 140 ° C., and wound on a take-up roll. Here, [T] / [E] obtained from the relationship between the single-hole discharge amount and the ejector pressure was 0.1.
The obtained fiber non-woven fabric was measured for basis weight, fineness, breaking strength of non-woven fabric, breaking strain, and coefficient of static friction, and cantilever measurement by the following measurement method. The measurement results are shown in Table 2.

[Age]
The weight of 5 cm x 5 cm of the obtained nonwoven fabric was measured, and the fabric weight (g / m < ² > ) was measured.

[Fineness]
The fibers in the non-woven fabric are observed using a polarization microscope, the average value (d) of the diameter of five randomly selected fibers is measured, and the density of the resin (ρ = 900000 g / m ³ ) is used to determine the non-woven fabric sample The fineness was calculated from the following [1].
Fineness (denier) = ρ × π × (d / 2) ² × 9000 ... [1]

[Breaking strength, breaking strain]
The obtained non-woven fabric sample of length 200 mm × width 50 mm was sampled in the machine direction (MD) and the direction perpendicular to the machine direction (CD). Using an tensile tester (Autograph AG-I, manufactured by Shimadzu Corporation), set the initial length L0 to 100 mm, stretch at a tensile speed of 300 mm / min, and measure the strain and load in the stretching process, The values of load and strain at the moment of breakage of the non-woven fabric were taken as breaking strength and breaking strain, respectively.

Coefficient of static friction
The obtained nonwoven fabric was sampled from a test piece of length 220 mm × width 100 mm and length 220 mm × width 70 mm in the machine direction (MD) and the direction perpendicular to the machine direction (CD). Place the two stacked nonwoven fabrics on a static friction coefficient measurement tester (friction measuring instrument AN type, manufactured by Toyo Seiki Kogyo Co., Ltd.), place a 1000 g weight on it, and tilt the pedestal by 2.7 degrees The coefficient of static friction was calculated from the weight (1000 g) of the weight and the angle when the non-woven fabric slipped by 10 mm while changing the speed at a rate of 1 / min, and the non-woven fabric slipped by 10 mm. The low coefficient of static friction indicates that the feel and feel of the non-woven fabric are good.

[Cantilever test]
From the obtained non-woven fabric, a test piece of length 100 mm × width 100 mm was produced, and a cantilever test machine having an inclined surface having an inclination angle of 45 ° at one end of the pedestal was used. The test piece was slid on the pedestal at a constant speed in a slope direction, and the movement distance at the moment when the test piece was bent and one end came in contact with the slope was measured. The machine direction (MD) and the direction perpendicular to the machine direction (CD) were measured respectively.

Example 2
A nonwoven fabric is formed in the same manner as in Example 1 except that the single hole discharge rate is 0.2 g / min, the ejector pressure is 4.0 kg / cm ² , and the line speed is 24 m / min in Example 1. The evaluation of The results are shown in Table 2. At this time, [T] / [E] obtained from the relationship between the single-hole discharge amount and the ejector pressure was 0.05.

Example 3
A nonwoven fabric is formed in the same manner as in Example 1 except that the single hole discharge rate is 0.3 g / min, the ejector pressure is 2.0 kg / cm ² , and the line speed is 35 m / min in Example 1. The evaluation of The results are shown in Table 2. At this time, [T] / [E] obtained from the relationship between the single-hole discharge amount and the ejector pressure was 0.15.

Comparative Example 1
In Example 1, except that the addition amount of low crystalline polypropylene is 1% by mass, the single hole discharge amount is 0.5 g / min, the ejector pressure is 2.0 kg / cm ² , and the line speed is 54 / min. A nonwoven fabric was formed in the same manner as in Example 1, and the same evaluation was performed. The results are shown in Table 2. At this time, [T] / [E] obtained from the relationship between the single-hole discharge amount and the ejector pressure was 0.25.

Comparative example 2
Example 1 is the same as Example 1 except that low crystalline polypropylene is not added, single hole discharge amount is 0.5 g / min, ejector pressure is 2.0 kg / cm ² , and line speed is 54 / min. A non-woven fabric was formed in the same manner and the same evaluation was performed. The results are shown in Table 2. At this time, [T] / [E] obtained from the relationship between the single-hole discharge amount and the ejector pressure was 0.25.

Example 4
(Preparation of resin composition)
10 parts by mass of low crystalline polypropylene (manufactured by Idemitsu Kosan Co., Ltd., “L-MODU (registered trademark) S901”, MFR: 50 g / 10 min, melting point: 70 ° C.), and highly crystalline polypropylene B (manufactured by ExxonMobil, “PP3155” MFR: 36 g / 10 min, melting point: 161 ° C.) A resin composition was prepared by adding 2000 ppm of erucic acid amide based on the resin mixture to a resin mixture consisting of 90 parts by mass.
The physical properties of the above-mentioned highly crystalline polypropylene B were measured by the above-mentioned measuring method. The results are shown in Table 1.

  Moreover, also about the said resin composition, half crystallization time was measured by the above-mentioned measuring method. Furthermore, the value obtained by dividing the half crystallization time of the resin composition by the half crystallization time of the highly crystalline polypropylene was taken as the relative crystallization time ratio. The results are shown in Table 3.

The resin composition is melted and extruded at a resin temperature of 250 ° C. using a single-screw extruder having a gear pump, and a single-hole discharge rate of 0.47 g / min is obtained from a nozzle with a nozzle diameter of 0.6 mm (5800 holes / m). The molten resin was discharged at a speed and spun. While cooling the fibers obtained by spinning with air, they were sucked by a cooling air duct under a nozzle at a cabin pressure of 8000 Pa, and the fibers were laminated on the moving net surface at a line speed of 180 m / min. The fiber bundle laminated on the net surface was embossed at a nip pressure of 100 N / mm with a calender roll heated to 140 ° C., and wound on a take-up roll. Here, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.06.
The obtained non-woven fabric was measured for basis weight, fineness, breaking strength of non-woven fabric, breaking strain, coefficient of static friction and cantilever measurement by the above-mentioned measurement method. The measurement results are shown in Table 3.

Example 5
In Example 4, a nonwoven fabric was formed in the same manner as in Example 4 except that the cabin pressure was changed to 6500 Pa, and the same evaluation was performed. The results are shown in Table 3. At this time, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.07.

Example 6
In Example 4, 15 parts by mass of low crystalline polypropylene and 85 parts by mass of high crystalline polypropylene B are mixed, a resin composition is prepared without addition of erucic acid amide, and cabin pressure is 7500 Pa, line A nonwoven fabric was formed in the same manner as in Example 4 except that the speed was changed to 150 m / min, and the same evaluation was performed. The results are shown in Table 3. At this time, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.05.

Example 7
A nonwoven fabric was formed in the same manner as in Example 6 except that the cabin pressure was set to 6000 Pa in Example 6, and the same evaluation was performed. The results are shown in Table 3. At this time, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.06.

Example 8
(Preparation of resin composition)
5 parts by mass of low crystalline polypropylene (manufactured by Idemitsu Kosan Co., Ltd., “L-MODU (registered trademark) S901”, MFR: 50 g / 10 min, melting point: 70 ° C.), and highly crystalline polypropylene B (manufactured by ExxonMobil, “PP3155” MFR: 36 g / 10 min, melting point: 161 ° C.) A resin composition was prepared by adding 2000 ppm of erucic acid amide based on the resin mixture to a resin mixture consisting of 95 parts by mass.

  Moreover, also about the said resin composition, half crystallization time was measured by the above-mentioned measuring method. Furthermore, the value obtained by dividing the half crystallization time of the resin composition by the half crystallization time of the highly crystalline polypropylene was taken as the relative crystallization time ratio. The results are shown in Table 3.

The resin composition is melt-extruded at a resin temperature of 245 ° C. using a single-screw extruder having a gear pump, and the single-hole discharge rate is 0.40 g / min from a nozzle with a nozzle diameter of 0.6 mm (5800 holes / m). The molten resin was discharged at a speed and spun. While cooling the fibers obtained by spinning with air, they were sucked by a cooling air duct under a nozzle at a cabin pressure of 5500 Pa, and the fibers were laminated on the moving net surface at a line speed of 530 m / min. The fiber bundle laminated on the net surface was embossed at a nip pressure of 100 N / mm with a calender roll heated to 146 ° C., and wound on a take-up roll. Here, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.07.
The obtained non-woven fabric was measured for basis weight, fineness, breaking strength of non-woven fabric, breaking strain, coefficient of static friction and cantilever measurement by the above-mentioned measurement method. The measurement results are shown in Table 3.

Example 9
(Preparation of resin composition)
20 parts by mass of low crystalline polypropylene (manufactured by Idemitsu Kosan Co., Ltd., “L-MODU S901”, MFR: 50 g / 10 min, melting point: 70 ° C.), and high crystalline polypropylene C (manufactured by Lyondell Basell, “ A resin composition was prepared by adding 2000 ppm of erucic acid amide based on the resin mixture to a resin mixture consisting of 80 parts by mass of Mopren HP 561 S ′ ′, MFR: 33 g / 10 min, melting point: 163 ° C.).
The physical properties of the above-mentioned high crystalline polypropylene C were measured by the above-mentioned measuring method. The results are shown in Table 1.

  Moreover, also about the said resin composition, half crystallization time was measured by the above-mentioned measuring method. Furthermore, the value obtained by dividing the half crystallization time of the resin composition by the half crystallization time of the highly crystalline polypropylene was taken as the relative crystallization time ratio. The results are shown in Table 3.

The resin composition is melted and extruded at a resin temperature of 240 ° C. using a single-screw extruder having a gear pump, and a single-hole discharge rate of 0.57 g / min is obtained from a nozzle with a nozzle diameter of 0.6 mm (5800 holes / m). The molten resin was discharged at a speed and spun. While cooling the fibers obtained by spinning with air, they were sucked by a cooling air duct under a nozzle at a cabin pressure of 6000 Pa, and the fibers were laminated on the moving net surface at a line speed of 214 m / min. The fiber bundle laminated on the net surface was embossed at a nip pressure of 70 N / mm with a calender roll heated to 136 ° C., and wound on a take-up roll. Here, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.10.
The obtained non-woven fabric was measured for basis weight, fineness, breaking strength of non-woven fabric, breaking strain, coefficient of static friction and cantilever measurement by the above-mentioned measurement method. The measurement results are shown in Table 3.

Comparative example 3
In Example 4, 1 part by mass of low crystalline polypropylene and 99 parts by mass of high crystalline polypropylene B are mixed, a resin composition is prepared without adding erucic acid amide, and the cabin pressure is 4500 Pa and the line speed is A nonwoven fabric was molded in the same manner as in Example 4 except that 220 m / min was used, and the same evaluation was performed. The results are shown in Table 3. At this time, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.13.

Comparative example 4
Example 4 is the same as Example 4 except that low crystalline polypropylene and erucic acid amide are not added, only high crystalline polypropylene B is used as a raw resin, cabin pressure is 4500 Pa, and line speed is 220 m / min. A non-woven fabric was formed in the same manner, and the same evaluation was performed. The results are shown in Table 3. At this time, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.14.

Comparative example 5
(Preparation of resin composition)
25 parts by mass of low crystalline polypropylene (manufactured by Idemitsu Kosan Co., Ltd., “L-MODU S901”, MFR: 50 g / 10 min, melting point: 70 ° C.), and high crystalline polypropylene C (manufactured by Lyondell Basell, “ 75 parts by mass of Mopren HP 561S ", MFR: 33 g / 10 min, melting point: 163 ° C. were mixed, and a resin composition was prepared without adding erucic acid amide.

  Moreover, also about the said resin composition, half crystallization time was measured by the above-mentioned measuring method. Furthermore, the value obtained by dividing the half crystallization time of the resin composition by the half crystallization time of the highly crystalline polypropylene was taken as the relative crystallization time ratio. The results are shown in Table 3.

The resin composition is melt extruded at a resin temperature of 236 ° C. using a single screw extruder having a gear pump, and a single hole discharge rate of 0.57 g / min is obtained from a nozzle with a nozzle diameter of 0.6 mm (5800 holes / m). The molten resin was discharged at a speed and spun. While cooling the fibers obtained by spinning with air, they were sucked by a cooling air duct under a nozzle at a cabin pressure of 5500 Pa, and the fibers were laminated on the moving net surface at a line speed of 215 m / min. The fiber bundle laminated on the net surface was embossed at a nip pressure of 90 N / mm with a calender roll heated to 134 ° C., and wound on a take-up roll. Here, [T] / [C] × 1000 obtained from the relationship between the single-hole discharge amount and the cabin pressure was 0.10.
The obtained non-woven fabric was measured for basis weight, fineness, breaking strength of non-woven fabric, breaking strain, coefficient of static friction and cantilever measurement by the above-mentioned measurement method. The measurement results are shown in Table 3.

  The fiber non-woven fabric of the present invention has an extremely small fiber diameter and good touch feeling, and is particularly preferably used for sanitary materials such as disposable diapers.

Claims (6)

A fibrous nonwoven fabric comprising a resin composition (C) containing a high crystallinity polyolefin (A) and a low crystallinity polyolefin (B), which satisfies the following condition (1),
The high crystalline polyolefin (A) is at least one selected from the group consisting of a propylene homopolymer, an ethylene-propylene copolymer, and a propylene-α-olefin copolymer,
The low crystalline polyolefin (B) has an initial elastic modulus of 5 MPa or more and less than 500 MPa,
The highly crystalline polyolefin (B) is at least one selected from the group consisting of a propylene homopolymer, an ethylene-propylene copolymer, and a propylene-α-olefin copolymer,
In the resin composition (C), the content of the high crystalline polyolefin (A) is 50 to 98% by mass, and the content of the low crystalline polyolefin (B) is 2 to 50% by mass,
The resin composition (C) further contains an internal mold release agent in an amount of 10 to 5000 mass ppm based on the total content of the high crystalline polyolefin (A) and the low crystalline polyolefin (B),
The internal mold release agent is dibenzylidene sorbitol, 1,3: 2,4-bis (o-3,4-dimethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-2,4-dimethylbenzylidene) ) Sorbitol, 1,3: 2,4-bis (o-4-ethylbenzylidene) sorbitol, 1,3: 2,4-bis (o-4-chlorobenzylidene) sorbitol, 1,3: 2,4-disorbate Consisting of benzylidene sorbitol, erucic acid amide, oleic acid amide, stearic acid amide, behenic acid amide, ethylene bis-stearic acid amide, ethylene bis oleic acid amide, stearyl erucamide and oleyl palmitamide, adipic acid dianilide, and suberic acid dianilide At least one selected from the group
The fineness of the fiber constituting the nonwoven fabric is from 0.2 to 0.6 de Neil, the fiber nonwoven fabric is a spunbonded nonwoven, fibrous nonwoven.
(1) half-crystallization time _{t b} of highly crystalline polyolefin (A) of the semi-crystallization time _{t a} and the low crystalline polyolefin (B) satisfies the relation of _t a _{<t b.} The fibrous nonwoven fabric fineness of the fibers constituting the is from 0.2 to 0.5 de Neil, nonwoven fabric of claim 1.   The fiber nonwoven fabric according to claim 1 or 2, wherein the initial modulus of elasticity of the highly crystalline polyolefin (A) is 500 to 2,000 MPa.   The fibrous nonwoven fabric according to any one of claims 1 to 3, wherein the internal mold release agent is erucic acid amide. A method for producing the fiber non-woven fabric according to any one of claims 1 to 4 using a spunbond non-woven fabric molding machine using an ejector method, wherein the fiber non-woven fabric is subjected to single hole discharge amount [T] ( g / min) to ejector pressure [E] (kg / cm ² ), the fiber non-woven fabric is a spunbonded non-woven fabric manufactured under the condition that the ratio [T] / [E] is 0.05 or more and 0.1 or less Production method.   The manufacturing method of the fiber non-woven fabric according to claim 5, wherein the single-hole discharge amount [T] is 0.1 to 0.5 g / min.