JP2003138428A - Polypropylene splittable multicomponent conjugate fiber and fiber molding product using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polypropylene splittable multicomponent conjugate fiber easily split into an ultra fine fiber, and to provide a fiber molding product using the conjugate fiber. SOLUTION: This polypropylene splittable multicomponent conjugate fiber is characterized by comprising at least two components of thermoplastic resins, wherein the components are alternately adjacent each other, one component of the thermoplastic resins is an α-olefin random copolymer polymerized by a metallocene catalyst and having 20-200 g/10 min MFR, 2.0-4.0 Q-value, 110-135 deg.C Tm, <=10 deg.C difference between T80 and T20 , <=3 wt.% soluble part at 0 deg.C in TREF determination and 1-18 mol% α-olefin content and the area of the copolymer in the fiber cross section is 20-80%.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene-based splitting type multi-component composite fiber and a fiber molded article using the same.

[0002]

2. Description of the Related Art Conventionally, a method for obtaining ultrafine fibers has been mainly obtained from splittable conjugate fibers. The method of using the splittable conjugate fiber is to combine a plurality of resin components into a composite fiber by spinning to obtain a composite fiber, and the resulting composite fiber is made into a large number of fibers by utilizing physical stress and difference in shrinkage of the resin with respect to a chemical agent. It is obtained by dividing into fine fibers. For example, a split type composite fiber of different polymers such as a combination of a polyester resin and a polyolefin resin, a combination of a polyester resin and a polyamide resin, and a combination of a polyamide resin and a polyolefin resin is used. When the treatment is carried out by the above method, the fibers of the respective resins are not melt-bonded to each other, so that the nonwoven fabric composed of the ultrafine fibers is obtained by dividing the fibers into ultrafine fibers.

Further, ultrafine fibers can be similarly obtained by using a splittable conjugate fiber made of a combination of similar resins such as polyolefin resins, polyester resins, polyamide resins, etc. Since the compatibility of the resin is relatively good, it is necessary to further increase the physical impact in order to make the fibers finely divided when processing into a non-woven fabric or the like, which increases the energy cost required for the fine division of the fibers. There was a problem. Furthermore, the obtained nonwoven fabric has so-called unevenness such that there are divided portions and non-divided portions, fibers move due to physical impact, and thick and thin portions with a basis weight are formed, resulting in poor texture. In addition, there is a problem in that it is necessary to significantly reduce the processing speed of the high pressure liquid flow treatment. In particular, using polypropylene-based resin, in olefin-based resins or in splittable conjugate fiber of polyolefin resin and other polymer, due to physical impact due to splitting treatment of the conjugate fiber,
There was a tendency that the basis weight of the non-woven fabric was deteriorated due to the unevenness of the basis weight caused by thick and thin portions.

To solve this problem, Japanese Unexamined Patent Publication No. 4-2
Japanese Patent No. 8922 discloses that by adding an organosiloxane and a modified product thereof to a resin, even splittable conjugate fibers having a combination of polymers of the same kind can be easily split. However, although the splittability is improved to some extent, the nonwoven fabric obtained by using the split fibers has problems such as reduced strength and poor processability in secondary processing.

[0005]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is a polypropylene-based splittable multi-component composite fiber in which splittable conjugate fibers are easily split using a polypropylene-based resin and can be easily ultrafine. And to provide a fiber molded product using the same.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have found that propylene having specific physical properties such as a low melting point obtained by polymerization with a metallocene catalyst and a narrow molecular weight distribution. A polypropylene-based splittable conjugate fiber having an α-olefin random copolymer as one component, a polymer having a high melting point as another component, and both components having a radial cross-sectional shape that are alternately arranged in the fiber cross section. However, they have found that the splitting process is extremely easy and uniform ultrafine fibers are obtained, and the present invention has been completed.

That is, according to the first aspect of the present invention,
In a split-type multi-component composite fiber composed of at least two components of thermoplastic resin, and each component is alternately adjacent in the fiber cross section, one component of the thermoplastic resin is polymerized by a metallocene catalyst, (1) ~
It is a propylene / α-olefin random copolymer having (6), and the ratio of the area occupied in the fiber cross section of the copolymer is 20 to 80%, and the propylene-based splitting type multi-component system is characterized. Composite fibers are provided. Characteristic (1): MFR is 20 to 200 g / 10 minutes Characteristic (2): Q value is 2.0 to 4.0 Characteristic (3): Tm is 110 to 135 ° C. Characteristic (4): T ₈₀ -T ₂₀ is 10 ° C or less Characteristic (5): 0 ° C soluble amount of 3% by weight at TREF measurement
The following characteristic (6): α-olefin content is 1 to 18 mol% (however, MFR is 230 ° C. according to JIS-K6921,
Melt flow rate at 21.18 N, Q value is the ratio (Mw / Mn) of weight average molecular weight Mw and number average molecular weight Mn measured by GPC, Tm is a differential scanning calorimeter (DSC)
The peak temperature of the melting curve obtained by T ₈₀ is the temperature at which 80 wt% is eluted in the integrated elution curve obtained by temperature rising elution fractionation (TREF), and T ₂₀ is the temperature at which 20 wt% is eluted. )

According to the second aspect of the present invention, the α-olefin of the propylene / α-olefin random copolymer is ethylene, and the content thereof is 1 to 1.
The polypropylene-based splittable multi-component conjugate fiber according to the first invention is provided, which is 2 mol%.

According to a third aspect of the present invention, the thermoplastic resin has a melting point difference of 10 ° C. or more between the propylene / α-olefin random copolymer and other components. A polypropylene-based splittable multi-component composite fiber according to the first or second invention is provided.

According to a fourth aspect of the present invention, in the thermoplastic resin, the propylene / α-olefin random copolymer and the other components each have a single fiber heat shrinkage ratio at 120 ° C. for 10 minutes. The polypropylene-based splittable multicomponent conjugate fiber according to any one of the first to third inventions is provided, wherein the difference is 10% or more.

According to a fifth aspect of the present invention, in the thermoplastic resin, a polypropylene resin in which other components than the propylene / α-olefin random copolymer are polymerized by a polyethylene resin or a Ziegler catalyst. A polypropylene-based splittable multicomponent conjugate fiber according to any one of the first to fourth inventions, which is a resin.

According to a sixth aspect of the present invention, in the thermoplastic resin, the component other than the propylene / α-olefin random copolymer is a polyester resin or a polyamide resin. First to fifth
There is provided a polypropylene-based splittable multi-component composite fiber according to any one of the inventions.

Further, according to the seventh invention of the present invention, the splitting ratio is 75% or more, and the polypropylene-based splittable multicomponent composite fiber according to any one of the first to sixth inventions. Will be provided.

According to an eighth aspect of the present invention, the first aspect
A fiber molded article using the polypropylene-based splittable multi-component composite fiber according to any one of the inventions is provided.

Further, according to the ninth invention of the present invention, there is provided the fiber molded article according to the eighth invention, wherein the fiber molded article is a fiber assembly.

According to a tenth aspect of the present invention, there is provided a laminated fiber molded article obtained by laminating sheets on one side or both sides of the fiber molded article according to the eighth or ninth aspect of the invention.

According to a seventh aspect of the present invention, there is provided a laminated fiber molded article obtained by laminating the fiber molded article according to claim 8 or 9 on both sides of a sheet.

According to the twelfth aspect of the present invention, the sheet is at least one of non-woven fabric, film, knitted fabric and woven fabric.
There is provided a laminated fiber molded article according to the tenth or eleventh invention, which is a sheet selected from species.

According to the thirteenth invention of the present invention, the fiber molded article or the tenth to tenth inventions described in the eighth or ninth invention is provided.
There is provided an absorbent article using the laminated fiber molded article according to any one of the inventions.

According to the fourteenth invention of the present invention, the fiber molded article or the tenth to twelfth invention described in the eighth or ninth invention is also provided.
There is provided a wiper using the laminated fiber molded article according to any one of the inventions.

According to the fifteenth invention of the present invention, the fiber molded article or the tenth to first invention described in the eighth or ninth invention is also provided.
There is provided a battery separator using the laminated fiber molded article according to any one of the inventions.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.
The propylene / α-olefin random copolymer used in the present invention is a copolymer obtained by using a metallocene catalyst. The metallocene catalyst is a catalyst that uses a complex of a transition metal of Groups 4 to 6 of the periodic table such as titanium, zirconium, and hafnium with a cyclopentadienyl group or a cyclopentadienyl derivative group.

In the metallocene catalyst, the cyclopentadienyl derivative group is an alkyl substituent such as pentamethylcyclopentadienyl, or two or more substituents are combined to form a saturated or unsaturated cyclic substituent. A group can be used, and typical examples thereof include an indenyl group, a fluorenyl group, an azulenyl group, and partial hydrogenated products thereof. Further, those in which a plurality of cyclopentadienyl groups are bound by an alkylene group, a silylene group, a germylene group or the like are also preferably used.

Specific examples of the metallocene complex preferably include the following compounds. (1) Methylenebis (cyclopentadienyl) zirconium dichloride, (2) Methylene (cyclopentadienyl) (3,4-dimethylcyclopentadienyl) zirconium dichloride, (3) Isopropylidene (cyclopentadienyl) (3 , 4-Dimethylcyclopentadienyl) zirconium dichloride, (4) ethylene (cyclopentadienyl) (3,5-dimethylpentadienyl)
Zirconium dichloride, (5) methylenebis (indenyl) zirconium dichloride, (6) ethylenebis (2-methylindenyl) zirconium dichloride,
(7) ethylene 1,2-bis (4-phenylindenyl) zirconium dichloride, (8) ethylene (cyclopentadienyl) (fluorenyl) zirconium dichloride, (9) dimethylsilylene (cyclopentadienyl) (tetramethylcyclo Pentadienyl) zirconium dichloride, (10) dimethylsilylenebis (indenyl) zirconium dichloride, (11) dimethylsilylenebis (4,5,6,7-tetrahydroindenyl)
Zirconium dichloride, (12) dimethylsilylene (cyclopentadienyl) (fluorenyl) zirconium dichloride, (13) dimethylsilylene (cyclopentadienyl) (octahydrofluorenyl) zirconium dichloride, (14) methylphenylsilylene bis [1 -(2-Methyl-4,5-benzo (indenyl)]
Zirconium dichloride, (15) dimethylsilylene bis [1- (2-methyl-4,5-benzoindenyl)]
Zirconium dichloride, (16) dimethylsilylene bis [1- (2-methyl-4H-azurenyl)] zirconium dichloride, (17) dimethylsilylene bis [1-
(2-Methyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, (18) dimethylsilylenebis [1- (2-ethyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride , (19) Dimethylsilylenebis [1- (2-ethyl-4-naphthyl-4H-azulenyl)] zirconium dichloride, (20) Diphenylsilylenebis [1-
(2-Methyl-4- (4-chlorophenyl) -4H-azurenyl)] zirconium dichloride, (21) dimethylsilylenebis [1- (2-methyl-4- (phenylindenyl))] zirconium dichloride, (22). Dimethylsilylenebis [1- (2-ethyl-4- (phenylindenyl))] zirconium dichloride, (23) Dimethylsilylenebis [1- (2-ethyl-4-naphthyl-4H-azulenyl)] zirconium dichloride, ( Two
4) dimethylgermylene bis (indenyl) zirconium dichloride, (25) dimethylgermylene (cyclopentadienyl) (fluorenyl) zirconium dichloride.

The same compounds as described above can be used for other Group 4, 5 and 6 transition metal compounds such as titanium compounds and hafnium compounds. These compounds may be used in combination with the catalyst component and catalyst of the present invention.

Further, compounds in which one or both of the chlorides of these compounds are replaced by bromine, iodine, hydrogen, methylphenyl, benzyl, alkoxy, dimethylamide, diethylamide and the like can be exemplified. further,
Instead of the above zirconium, compounds in which titanium, hafnium, etc. are replaced can be exemplified.

The cocatalyst is composed of an ionic compound capable of converting a metallocene compound component into a cation by reacting with an aluminumoxy compound or a metallocene compound, a Lewis acid, a solid acid, or an ion-exchange layered silicate. At least one compound selected from the group is used. Moreover, an organoaluminum compound can be added together with these compounds as needed.

Examples of the aluminumoxy compound include methylalumoxane, ethylalumoxane, propylalumoxane, butylalumoxane, isobutylalumoxane, methylethylalumoxane, methylbutylalumoxane, methylisobutylalumoxane and the like.
It is also possible to use a reaction product of a trialkylaluminum and an alkylboronic acid. For example, a 2: 1 reaction product of trimethylaluminum and methylboronic acid, a 2: 1 reaction product of triisobutylaluminum and methylboronic acid, a 1: 1: 1 reaction product of trimethylaluminum and triisobutylaluminum and methylboronic acid, triethylaluminum and butylboron. 2: 1 reaction of acid and the like.

Examples of the ion-exchange layered silicate include montmorillonite, sauconite, beidellite, nontronite, saponite, hectorite, stevensite,
A silicate such as a smectite group such as bentonite or teniolite, a vermiculite group, or a mica group is used.
It is preferable that these silicates have been chemically treated. Here, as the chemical treatment, both surface treatment for removing impurities adhering to the surface and treatment for affecting the crystal structure and chemical composition of the layered silicate can be used. Specifically, (a) acid treatment, (b) alkali treatment, (c) salt treatment, (d) organic substance treatment and the like can be mentioned. These treatments remove impurities on the surface, exchange cations between layers, and elute cations such as Al, Fe, and Mg in the crystal structure, resulting in ionic complexes, molecular complexes, organic derivatives, etc. Can be formed to change the surface area, interlayer distance, solid acidity, and the like. These treatments may be performed alone or two or more treatments may be combined.

If necessary, triethylaluminum, triisobutylaluminum,
Organoaluminum compounds such as diethyl aluminum chloride may also be used.

In the present invention, a propylene / α-olefin random copolymer is obtained by using the above metallocene catalyst. Examples of the α-olefin include α-olefins having 2 to 20 carbon atoms excluding propylene, and examples thereof include ethylene, butene-1, pentene-1,3-methyl-1-butene, hexene-1,3-methyl-1. -Penten, 4-
Methyl-1-pentene, heptene-1, octene-1,
Examples include nonene-1, decene-1, dodecene-1, tetradecene-1, hexadecene-1, octadecene-1, eicosene-1. Α-copolymerized with propylene
The olefins may be used alone or in combination of two or more. Of these, ethylene and butene-1 are preferable, and ethylene is particularly preferable.

As the polymerization method, in the presence of these catalysts,
Examples thereof include a slurry method using an inert solvent, a gas phase method or a solution method substantially using no solvent, and a bulk polymerization method using a polymerization monomer as a solvent.

The propylene / α-olefin random copolymer used in the present invention is a copolymer polymerized with the above-mentioned metallocene catalyst and must have the following properties (1) to (6). is there. Hereinafter, each characteristic will be described.

(1): MFR MFR is 230 ° C. according to JIS-K6921, 21.
It represents the melt flow rate at 18N. MF of propylene / α-olefin random copolymer used in the present invention
R is 20 to 200 g / 10 minutes, preferably 22
~ 150 g / 10 minutes, more preferably 25 to 10
It is 0 g / 10 minutes. When the MFR is less than 20 g / 10 minutes, the spinning pressure becomes too high, which causes problems such as operability and nonuniform fiber diameter. On the other hand, when it exceeds 200 g / 10 minutes, the melt viscosity is low, so that the yarn swaying becomes noticeable immediately below the nozzle during melt spinning, and yarn breakage occurs due to contact between adjacent yarns, resulting in reduced productivity. The harmful effect of occurs. In order to control the MFR of the polymer, for example, there are a method of appropriately controlling the polymerization temperature, a catalyst amount, a supply amount of hydrogen as a molecular weight regulator, or a method of adjusting by adding a peroxide after the completion of the polymerization.

(2): Q value The Q value represents the ratio (Mw / Mn) of the weight average molecular weight Mw and the number average molecular weight Mn measured by GPC. The Q value of the propylene / α-olefin random copolymer used in the present invention is 2.0 to 4.0, preferably 2.2.
It is 3.7, and more preferably 2.3 to 3.5.
When the Q value exceeds 4.0, the presence of a high molecular weight causes a problem of impairing the stretchability. On the other hand, when it is less than 2.0, the high-molecular weight component is too small, so that the viscosity of the melted fiber immediately below the spinning nozzle becomes low, the yarn swaying accompanying this becomes remarkable, and the spinning stability is impaired, which is not preferable. . Q of propylene / α-olefin random copolymer
The method for adjusting the value is preferably polymerization using a catalyst system in which two or more metallocene catalyst components are used in combination or a catalyst system in which two or more metallocene complexes are used in combination, or 2
The Q value can be widely controlled by carrying out multistage polymerization of more than one stage. On the contrary, in order to adjust the Q value narrowly, it can be adjusted by polymerizing the propylene / α-olefin random copolymer and then melt-kneading it with an organic peroxide.

The Q value is specifically measured under the following conditions. Apparatus: Waters HLC / GPC 150C Column temperature: 135 ° C. Solvent: o-dichlorobenzene Flow rate: 1.0 ml / min Column: Tosoh Corporation GMH _HR- H (S) HT 60 cm × 1 Injection amount: 0.15 ml (No filtration treatment) Solution concentration: 5 mg / 3.4 ml Sample preparation: Using o-dichlorobenzene, adjust to a solution of 5 mg / 3.4 ml and dissolve at 140 ° C. for 1 to 3 hours. Calibration curve: polystyrene standard sample is used. Calibration curve order: primary PP molecular weight: PS x 0.639

(3): Tm The Tm of the propylene / α-olefin random copolymer used in the present invention represents the peak temperature of the melting curve obtained by a differential scanning calorimeter (DSC), 110 to 135 ° C.
Is. When Tm exceeds 135 ° C, 100-120 ° C
Since there is no difference in the thermal shrinkage ratio of the component in question from the other components, pre-division due to the difference in shrinkage ratio does not proceed when heat-treated before the division treatment with the high-pressure fluid, which is not preferable. Also,
When the temperature is lower than 110 ° C., when water is used as the high-pressure fluid for the splitting treatment, when the nonwoven fabric is dried by a suction drum dryer or the like, the fibers are melted and partially formed into a film, and the nonwoven fabric is flexible. It lacks sex and is not desirable. T
In order to adjust m, it can be easily adjusted by controlling the amount of α-olefin supplied to the polymerization reaction system.

A specific measurement of Tm was carried out by using a differential scanning calorimeter (DSC) manufactured by Perkin Elmer Co., Ltd., a sample amount of 10 mg was taken, and the sample was kept at 200 ° C. for 5 minutes, and then 40
Crystallize up to 10 ° C at a rate of 10 ° C / min, then 10 ° C
The melting peak temperature Tm (° C.) is the peak position of the curve drawn when melting is performed at a heating rate of / min.

(4): T₈₀-T₂₀ T₈₀Is obtained by elevated temperature elution separation (TREF)
In the elution curve, the temperature at which 80% by weight elutes, T₂₀
Represents the temperature at which 20% by weight elutes. Used in the present invention
In propylene / α-olefin random copolymer
Is T₈₀-T ₂₀Is 10 ° C. or less, preferably 2
-9 ° C, more preferably 2-8 ° C. T₈₀
-T₂₀When the temperature exceeds 10 ° C, the low melting point component increases
Therefore, these ingredients are not sticky or slimy on the surface of the nonwoven fabric.
It is not preferable because it may cause a feeling and fuzz. Of polymer
T₈₀-T₂₀Is within a certain narrow range as described above.
Means that the molecular weight distribution of the polymer is more uniform.
I'm tasting. Propylene / α-Olefin Random Copolymer
Combined T₈₀-T₂₀The method of adjusting the
A catalyst system in which a talocene catalyst component is used in combination and two or more metallo
By polymerizing using a catalyst system with a sen complex
, T₈₀-T₂₀Can be greatly adjusted. Well
In addition, when loading the metallocene catalyst component on the carrier,
Low molecular weight component when polymerized using a homogeneous catalyst
Is increasing, and T₈₀-T₂₀Will grow
U Therefore, the metallocene catalyst component is uniformly loaded on the carrier.
The technology to do is important.

Here, the temperature rising elution fractionation (TRE
F) means that the polymer is completely dissolved in the presence of an inert carrier at a constant high temperature and then cooled to form a thin polymer layer on the surface of the inert carrier, and then the temperature is continuously or gradually increased. This is a method in which the temperature is raised, the eluted components are recovered, the concentration thereof is continuously detected, and the composition distribution of the polymer is measured by a graph (elution curve) drawn by the elution amount and the elution temperature. For more information on elevated temperature elution fractionation (TREF) measurements, see Journal of Applies.
d Polymer Science Vol. 26, No. 42
17 to 4231 (1981).

Incidentally, T ₈₀ -T ₂₀ is specifically a value measured under the following conditions. As the measuring device, CFC T-102L manufactured by Dia Instruments is used. First, a sample to be measured is dissolved at 140 ° C. using a solvent (o-dichlorobenzene) so as to be 3 mg / ml, and this is measured. Inject into the sample loop inside. The following measurements are automatically performed according to the set conditions. The sample solution held in the sample loop is separated into a TREF column (a stainless steel column with an inner diameter of 4 mm and a length of 150 mm, which is filled with an inert carrier, glass beads), which is separated by utilizing the difference in melting temperature. 0.4 ml is injected. The sample is then run from 140 ° C to 0 at a rate of 1 ° C / min.
Allow to cool to a temperature of ° C. After the TREF column was kept at 0 ° C. for another 30 minutes, 2 ml of the dissolved component at 0 ° C. was passed through the SEC from the TREF column at a flow rate of 1 ml / min.
It is injected into a column (3 AD806MS manufactured by Showa Denko). While molecular size separation is being performed by SEC, T
In the REF column, the temperature was raised to the next elution temperature (10 ° C),
Hold at that temperature for about 30 minutes. The measurement of each elution section by SEC is performed at intervals of 39 minutes. Elution temperature is 0 ℃ to 4
0 ° C every 10 ° C, 40 ° C to 90 ° C every 5 ° C,
From 90 ° C to 140 ° C, the temperature is raised stepwise at every 4 ° C. The solution separated by the molecular size in the SEC column is detected by an infrared spectrophotometer attached to the apparatus, and a chromatograph in each elution temperature section can be obtained. The infrared spectrophotometer performs detection using the absorbance at a detection wave number of 3.42 μm, and the following data processing is performed assuming that the amount of the polymer component in the solution is proportional to the absorbance. The chromatogram in each elution temperature segment is processed by the built-in data processing software, and the elution amount in each elution temperature segment is calculated based on the area of each chromatogram so that the integration is 100%. Furthermore, an integrated elution curve is created from the elution amount of each elution temperature segment obtained. The 0 ° C. soluble content indicates the amount (%) of the polymer component eluted at 0 ° C., and T ₂₀ is the cumulative elution amount of 20.
%, And T ₈₀ is the temperature at which the cumulative elution amount becomes 80%.

(5): 0 ° C. soluble amount at the time of TREF measurement The propylene / α-olefin random copolymer used in the present invention has a 0 ° C. soluble amount at the time of TREF measurement of 3% by weight or less, preferably. It is 1.0% by weight or less, more preferably 0.5% by weight or less, particularly preferably 0.1% by weight.
It is 3% by weight or less. Most of the 0 ° C soluble components at the time of TREF measurement are low molecular weight components or components with extremely high ethylene concentration, and the components are 3% by weight.
Existence of more than 1 is not preferable because it causes stickiness, slimy feel and fuzz on the surface of the nonwoven fabric. propylene·
When the metallocene catalyst component is loaded on the carrier, the amount of TREF soluble components of the α-olefin random copolymer is low when the polymerization is carried out using a catalyst whose loading is non-uniform. Soluble content will increase. Therefore, the amount of TREF soluble at 0 ° C. can be adjusted to 3% by weight or less by polymerizing using a catalyst in which the metallocene catalyst component is uniformly supported on the carrier.

(6) α-Olefin Content The content of α-olefin (comonomer) in the propylene / α-olefin random copolymer used in the present invention is 1
It is necessary to adjust to -18 mol%. The comonomer content is preferably 2.5-10 mol%, more preferably 3-8 mol%. Particularly when the comonomer is ethylene, 1 to 12 mol% is preferable. When the comonomer content is less than the above range, the melting point becomes high, and the heat shrinkage rate of the component at 100 to 120 ° C. does not differ from that of the other components. In addition, pre-division due to the difference in shrinkage does not proceed, which is not preferable. On the other hand, if too much water is used as the high-pressure fluid for the splitting process, when the nonwoven fabric is dried by a suction drum dryer or the like, the fibers are melted to partially form a film, and the nonwoven fabric becomes flexible. Chipping, not preferable. The α-olefin content in the polymer can be easily adjusted by controlling the amount of α-olefin supplied to the polymerization reaction system. In the present invention,
The α-olefin content is quantified by a Fourier transform infrared spectrophotometer.

The propylene / α-olefin random copolymer of the present invention contains various additives such as a heat resistance stabilizer, an antioxidant, a weather resistance stabilizer, and an ultraviolet absorber as long as the object of the present invention is not impaired. , A crystal nucleating agent, a copper damage preventing agent, an antistatic agent, a slip agent, an antiblocking agent, an antifogging agent, a coloring agent, a filler, an elastomer, a petroleum resin and the like can be added.

The polypropylene resin composition which is the molding material of the split fiber in the present invention contains the above-mentioned propylene / α-olefin random copolymer and, if necessary, the above-mentioned various additives, other resin components and the like. It is provided in the form of pellets which are in the form of a blend or are melt-kneaded by heating at 180 to 300 ° C. using a melt-kneader and cut into granules.

As the other component of the split fiber, a thermoplastic resin other than the propylene / α-olefin random copolymer polymerized with the metallocene catalyst can be used,
For example, a polyamide resin, a polyethylene terephthalate resin (PET), a linear low density polyethylene, a low density polyethylene, a polyethylene resin such as high density polyethylene (HDPE), a polypropylene resin polymerized by a Ziegler catalyst, and the like can be mentioned. To be The PET used in the present invention is preferably one in which the main repeating unit is ethylene terephthalate, but 1,4-butanediol, 1,
Copolymerization of diol components such as 6-hexanediol, aromatic diol components such as ethylene oxide adducts of bisphenol A, aliphatic dicarboxylic acid components such as adipic acid and sebacic acid, aromatic dicarboxylic acid components such as isosteric acid In addition, a stabilizer, a neutralizing agent, a fluorescent agent, a pigment or the like may be added. Also, HDPE
As long as it is higher than the melting point of the propylene / α-olefin random copolymer polymerized by the metallocene catalyst by 10 ° C. or more, the combination of both components preferably has a melting point difference of 10 ° C. or more. Melting point difference is 10 ℃
If it is less than 1, it is not preferable because preliminary division does not proceed when heat treatment is performed before the division treatment. Furthermore, it is preferable to use a combination of resins such that the difference in the heat shrinkage ratio at 120 ° C. for 10 minutes when each component is a single fiber is 10% or more. If the difference in heat shrinkage is less than 10%, pre-division due to the difference in shrinkage does not proceed, which is not preferable.

The splittable conjugate fiber of the present invention is composed of at least two components of the above propylene / α-olefin random copolymer and the above thermoplastic resin, and is preferably a radial cross-section splittable conjugate fiber. . In the fiber cross section of the conjugate fiber, the area ratio occupied by the propylene / α-olefin random copolymer is 20 to 80%, more preferably 30 to 70%. Area ratio is 20%
When the amount is less than the above, when the heat treatment is performed before the splitting treatment with the high-pressure fluid, the amount of the component is too small, and the preliminary splitting due to the difference in shrinkage does not proceed, which is not preferable. On the other hand, if it exceeds 80%, the amount of the component is too large, and pre-division due to the difference in shrinkage does not proceed, which is not preferable.

When the splittable conjugate fiber obtained in the present invention is split by a high-pressure liquid flow treatment or the like, the average fineness of the ultrafine fiber after splitting is preferably 0.5 decitex or less. Therefore, the number of divided segments of the splittable conjugate fiber may be determined so that the average fineness of the ultrafine fibers is 0.5 decitex or less. If the number of splits is large, there is an advantage that the fineness after splitting becomes small. It is preferable to divide into. The single yarn fineness before division is not particularly limited, but is preferably 0.5 to 10.0 decitex.

As the method for producing the splittable conjugate fiber of the present invention, a long fiber made of the above resin is spun out using an ordinary melt spinning machine, and if necessary, drawn, and the obtained tow is given a predetermined length. In some cases, the web is cut into short fibers, and in other cases, the long fiber tows are cut into webs without cutting the tows. Thereafter, if necessary, a high-order processing step is performed, and the fiber molded body is formed according to the application. Further, after spinning and drawing, it is wound as a filament yarn or the like and knitted or woven to fabricate a knitted or woven fabric, or the above short fibers are spun yarn, and then knitted or woven to fabricate a knitted or woven fabric. It may be formed in. Examples of the fiber molded body include a cloth-like form, for example, a woven fabric, a knitted fabric, a nonwoven fabric, or a non-woven fiber aggregate. The non-woven fiber aggregate refers to, for example, a web-like material made uniform by a method such as a card method, an airlaid method or a papermaking method.

As a method for producing a nonwoven fabric composed of the splittable conjugate fiber of the present invention, for example, the short fiber produced by the splittable conjugate fiber producing method is used, and the card method, the airlaid method, or the papermaking method is used. It can be manufactured. Alternatively, the web may be directly manufactured by a melt blown method, a spun bond method, or the like. The web produced by the above method,
A fiber molding can be obtained by dividing and finely dividing by a known method such as a needle punching method, an oven heat treatment, a high pressure liquid flow treatment, or a pressurized calender roll.

The basis weight of the non-woven fabric, which is a fiber molded body, is not particularly limited, but is preferably 10 to ²⁰⁰ g / m ² . When the basis weight is less than 10 g / m ² , if the splittable conjugate fiber is divided and finely divided by physical stress such as high-pressure liquid flow treatment to produce the nonwoven fabric, the nonwoven fabric may have a poor texture. On the other hand, when the basis weight exceeds 200 g / m ² , the basis weight is high and a high-pressure water flow is required, which may make it difficult to perform uniform division with good texture.

The high pressure liquid flow treatment for finely dividing fibers is
For example, it is preferable to use a high-pressure liquid flow device in which a large number of injection holes having a hole diameter of 0.05 to 1.5 mm are arranged in one row or a plurality of rows with a hole interval of 0.1 to 1.5 mm. The resulting high pressure liquid stream impinges on the web placed on the porous support member. As a result, the undivided splittable conjugate fiber of the present invention is entangled and simultaneously finely divided by the high-pressure liquid flow. As the high-pressure liquid stream, normal temperature or warm water may be used, and optionally another liquid may be used. The distance between the injection hole and the web is 10 to 150.
It is preferably mm. Further, the processing pressure of this high-pressure liquid flow depends on the production method and the required performance of the fiber molding,
Although controlled, it is generally better to inject a high pressure liquid stream of 2-20 MPa. The porous support member on which the web is placed when the high-pressure liquid flow is applied is, for example, a mesh screen made of wire mesh or synthetic resin of 50 to 200 mesh or a perforated plate, as long as the high-pressure liquid flow penetrates the web. There is no particular limitation. After further high pressure liquid flow treatment, water is removed from the treated fiber molded body. A known method can be used to remove the water. For example, after the water is removed to some extent by using a squeezing device such as a mang roll, the water can be completely removed by using a drying device such as a hot air circulation dryer to obtain the fiber molded article of the present invention.

The web containing the splittable conjugate fiber of the present invention is subjected to high-pressure liquid flow treatment or the like for splitting into fine fibers, and the splitting rate is preferably 75% or more. If the division ratio is less than 75%, a dense fiber molded product cannot be obtained. Since the splittable conjugate fiber of the present invention is easily split, the physical impact by the high-pressure liquid flow is small, and the high-pressure liquid flow treatment, which is the rate-determining step of the nonwoven fabric processing step, and the high-pressure liquid flow are reduced in pressure. Since the formation can be improved, for example, the pressure of the high-pressure liquid stream can be lowered, problems such as the formation of the fiber molded body being disturbed and the through holes being opened can be improved.

The polypropylene-based splittable conjugate fiber of the present invention can be easily split, and a dense and well-formed fiber molded body can be obtained. Using these fiber molded bodies, battery separators, wipers, etc. It can be suitably used not only in the industrial material field, but also in the sanitary material field and the clothing field. Further, a laminated fiber molded article obtained by laminating a sheet made of at least one kind selected from a non-woven fabric, a film, a knitted fabric, a woven fabric or the like on one side or both sides of the fiber molded article of the present invention, or the fiber molded article in reverse. It is also possible to use a laminated fiber molded body in which both sides of the sheet are laminated. Any of these laminated fiber moldings can be suitably used in the field of hygiene materials represented by absorbent articles such as diapers and napkins, and in the field of industrial materials such as wipers and battery separators.

[0055]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist. The measurement of physical properties and the like is as follows. In addition, a method for producing a resin constituting the resin composition used in Examples and Comparative Examples is shown in Polymerization Examples.

(1) MFR measuring method: JIS-K692
1-2 Measured according to Annex. (Condition: temperature / 230
℃, load 21.18N)

(2) Q value: The measurement was performed according to the above-mentioned measuring method. Calibration curve: The polystyrene standard sample in Table 1 was used.

[0058]

[Table 1]

(3) Melting peak temperature (Tm): measured by the method described above.

[0060] According to (4) Temperature rising elution fractionation _{(TREF), T 80 -T 20} , 0 ℃ soluble content: measuring apparatus using a CFC T-102L manufactured by Dia Instruments, was measured by the method described above.

(5) Evaluation of spinnability: The number of yarn breakages during melt spinning for 30 minutes was judged according to the following criteria. ◯: The number of thread breaks is 0 to 3 times Δ: The number of thread breaks is 4 to 7 times ×: The number of thread breaks is 8 times or more

(6) Evaluation of heat shrinkage rate of single fiber: Melt spinning drawing was carried out under the following conditions, and the fiber was heated in an oven for 120 hours.
The heat shrinkage was measured under the condition of 10 ° C. for 10 minutes. Spinning and drawing conditions Spinning nozzle: φ0.8 mm × 40 holes Spinning temperature: 200 ° C. to 230 ° C. Discharge rate: 0.6 g / min / hole First roll rotation speed: 200 m / min, temperature: 70 ° C. Second roll rotation speed: 500 m / min, temperature: 80-100
℃ 3rd roll rotation speed: 600 m / min, temperature: 80-100
℃ 4th roll rotation speed: 600 m / min, temperature: 80-100
℃ Winding speed: 600m / min

(7) Division rate: The state of division of the cross section of the non-woven fabric after the high pressure liquid flow treatment was observed with an electron microscope and judged according to the following criteria. A division rate of 75% or more was passed. ◎: Dividing rate 90% or more ○: Dividing rate 75% or more and less than 90% △: Dividing rate 60% or more and less than 75% ×: Less than 60%

(8) Nonwoven fabric formation: Five panelists evaluated the thickness unevenness and feel of the nonwoven fabric surface after division by visual observation and touch, and judged according to the following criteria. ◎: The surface is dry and no fluffing ○: There is a slight fluffing, but the surface has a feeling of dryness △: There is a slimy feeling on the surface and there is a little fluffing ×: There is a feeling of slimy surface and many fluffing

Polymerization Example 1 (1) Preparation of catalyst Into a three-necked flask (volume: 1 L), 20 g of smectite group silicate (Ben clay SL manufactured by Mizusawa Chemical Co., Ltd.) sequentially treated with sulfuric acid and 200 mL of heptane were charged, It was treated with 50 mmol of trinormal octylaluminum and then washed with heptane to obtain a slurry 1. In another flask (volume 200 mL), heptane 90 mL, [(r) -dichloro [1,1'-dimethylsilylenebis {2-methyl-4- (4-chlorophenyl) -4H-azurenyl}]
Zirconium] 0.3 mmol and triisobutylaluminum 1.5 mmol were prepared as a slurry 2. Slurry 2 was added to Slurry 1 and stirred at room temperature for 60 minutes. Thereafter, 210 mL of heptane was added, and this slurry was introduced into a 1 L autoclave. After the internal temperature of the autoclave was set to 40 ° C, propylene was fed at a rate of 10 g / hour to carry out preliminary polymerization while maintaining 40 ° C for 4 hours.
The residual polymerization was carried out for a period of time to obtain 83 g of a preliminary polymerization catalyst.

(2) Production of propylene / α-olefin random copolymer In a reactor having an internal volume of 270 L, liquid propylene, ethylene,
Hydrogen, and triisobutylaluminum (TIBA)
Was continuously fed to maintain the internal temperature at 62 ° C. The supply amount of propylene was 38 kg / hr, the supply amount of ethylene was 1.6 kg / hr, the supply amount of hydrogen was 0.33 g / hr, and the supply amount of TIBA was 18 g / hr. The preliminary polymerization catalyst was slurried with liquid paraffin and fed at 0.75 g / hr. As a result, 12.0 kg / hr of propylene / ethylene random copolymer I was obtained. The obtained propylene / ethylene random copolymer I had MFR = 23.
0 g / 10 minutes, ethylene content = 6.3 mol%, Tm =
It was 120 ° C. and the Q value was 2.8.

Polymerization Example 2 Using the solid catalyst prepared in Polymerization Example 1, ethylene was supplied at a rate of 1.1 kg / hr and hydrogen was supplied at a rate of 0.22 g / h.
r, except that the feed amount of the prepolymerization catalyst made into a slurry with liquid paraffin was changed to 1.07 g / hr,
Polymerization was carried out in the same manner as Polymerization Example 1. As a result, 12.
1 kg / hr of propylene / ethylene random copolymer II was obtained. The obtained propylene / ethylene random copolymer II has MFR = 22.0 g / 10 minutes, ethylene content = 5.0 mol%, Tm = 125 ° C., and Q value = 2.7.
Met.

Polymerization Example 3 Using the solid catalyst prepared in Polymerization Example 1, the ethylene feed rate was 0.97 kg / hr and the hydrogen feed rate was 0.01 g / h.
Polymerization was carried out in the same manner as in Polymerization Example 1 except that the feed amount of the prepolymerization catalyst was made into a slurry with liquid paraffin and the feed amount was changed to 3.6 g / hr. As a result, 12.3
kg / hr propylene / ethylene random copolymer I
II was obtained. The obtained propylene / ethylene random copolymer III has MFR = 1.3 g / 10 minutes, ethylene content = 5.5 mol%, Tm = 127 ° C., and Q value = 2.7.
Met.

100 parts by weight of this polymer III powder
On the other hand, as a crystal nucleating agent, 3-methylbutene polymer
0.10 parts by weight of masterbatch as an antioxidant
1,3,5-tris [(4-tert-butyl-3-hi
Droxy-2,6-xylyl) methyl] -1,3,5-
Triazine-2,4,6 (1H, 3H, 5H) -trio
(Made by Cytec, product name Sianox 1790)
0.04 parts by weight, tris- (2,4-di-t-butylphene)
Phenyl) Phosphite (Ciba Specialty Chemica)
Made by Ruze, brand name Irgaphos 168) 0.05 parts by weight,
Calcium stearate as a neutralizer (Nitto Kasei
Made by trade name Ca-St) 0.05 parts by weight, and peroxide
(Perhexa 25B: manufactured by NOF CORPORATION) 0.1
0 parts by weight is blended, 500 rpm with a Henschel mixer,
After mixing at high speed for 3 minutes, φ50 mm single screw extruder (UNIO
Plastics) and an extrusion temperature of 230 ° C.
Depending on the situation, melting, kneading, cooling, cutting and pelletizing
Pyrene-based copolymer composition III ^*Was prepared. By this
, MFR 20g / 10 min, Q value modified to 1.8
Body composition III^*Got

Polymerization Example 4 After thoroughly replacing the stirring autoclave having an internal volume of 200 liters with propylene, 60 L of dehydrated and deoxygenated n-heptane was introduced, and 16 g of diethylaluminum chloride and a titanium trichloride catalyst (M and・ M company
4.1 g were introduced at 50 ° C. under a propylene atmosphere. Further, while maintaining the gas phase hydrogen concentration at 6.0% by volume, at a temperature of 50 ° C., 5.7 kg of propylene and 0.2 of ethylene.
After feeding for 4 hours at a rate of 8 kg / hour, the polymerization was continued for another hour. As a result, 12 kg of propylene / ethylene random copolymer IV was obtained. The propylene / ethylene random copolymer IV thus obtained had MFR = 6.4.
g / 10 minutes, ethylene content = 5.9 mol%, Tm = 1
It was 40 ° C. and the Q value was 4.4.

With respect to 100 parts by weight of this polymer IV powder, 0.10 parts by weight of a masterbatch of 3-methylbutene polymer as a crystal nucleating agent and 1, as an antioxidant,
3,5-Tris [(4-tert-butyl-3-hydroxy-2,6-xylyl) methyl] -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (Cytec Manufactured by Cyanox 1790) and 0.04 parts by weight of tris- (2,4-di-t-butylphenyl) phosphite (Ciba Specialty Chemicals, trade name Irgaphos 168). ,
As a neutralizing agent, 0.05 part by weight of calcium stearate (manufactured by Nitto Kasei Co., Ltd., trade name Ca-St) and 0.0% of peroxide (Perhexa 25B: manufactured by NOF CORPORATION) are used.
Add 3 parts by weight and use a Henschel mixer at 500 rpm,
After high-speed mixing for 3 minutes, using a φ50 mm single screw extruder (manufactured by Union Plastics Co., Ltd.), and extruding at a temperature of 230 ° C., melting, kneading, cooling, cutting, and pelletizing the propylene copolymer composition IV ^*. Was prepared. This allows
A polymer composition IV ^* modified to have an MFR of 25 g / 10 minutes and a Q value of 3.8 was obtained.

Example 1 As the polymer A constituting the split fiber, 100 parts by weight of the powder of the propylene / ethylene random copolymer I polymerized with the metallocene catalyst shown in Table 2 was used, and 3-methylbutene-as a crystal nucleating agent was added. 0.10 part by weight of a masterbatch of 1 polymer, 1,3,5-tris [(4-tert-butyl-3-hydroxy-2,6-
Xylyl) methyl] -1,3,5-triazine-2,
0.04 parts by weight of 4,6 (1H, 3H, 5H) -trione (manufactured by Cytec, trade name Syanox 1790), tris- (2,4-di-t-butylphenyl) phosphite (Ciba Specialty. 0.05 parts by weight of Chemicals, trade name Irgaphos 168) and 0.05 parts by weight of calcium stearate (Nitto Kasei Kogyo, trade name Ca-St) as a neutralizing agent are mixed at a high speed for 3 minutes at 500 rpm with a Henschel mixer. After that, using a φ50 mm single-screw extruder (manufactured by Union Plastics Co., Ltd.), and extruding at a temperature of 230 ° C., melting, kneading, cooling, and cutting, and using the pelletized propylene copolymer composition I, the component B As shown in Table 2, high density polyethylene (HDPE; H
J490; manufactured by Nippon Polychem Co., Ltd.) and using a composite spinneret in which the fiber cross-sectional shape is alternately divided into 12 segments, and the melt volume ratio of polymer A and polymer B is 50:50.
Melt-spun and stretched at a ratio of 2.2 to 6 monofilaments (polymer A has a segment fineness of about 0.15 dsix, polymer B has a segment fineness of about 0.21 dix), and is a split type composite having a fiber length of 51 mm. Fiber was obtained. The moisture content of the obtained splittable conjugate fiber is 20% by weight,
Using a square sheet machine (25 cm × 25 cm), a nonwoven fabric having a basis weight of 60 g / m ² was obtained by a papermaking method. Next, the obtained non-woven fabric is treated with hot air and then supplied onto a belt conveyor composed of a 100-mesh plain woven mesh screen, and three-stage injection nozzles having a plurality of injection holes having a hole diameter of 0.12 mm and a hole interval of 1.0 mm are provided. , The whole stage is 2 MPa, the middle stage is 4 MPa, and the latter stage is 5 to 10 MPa, and the high pressure fluid treatment by hydroentangling treatment is applied to the front and back of the nonwoven fabric to divide and entangle the constituent fibers of the web to obtain a finely woven nonwoven fabric. . The distance between the injection nozzle and the net conveyor is 5
At 0 mm, the speed of the net conveyor was 20 m / min. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture. The fineness is 10,000 m based on the fineness A method of JIS L1015 chemical fiber staple test method.
It is the value converted by.

Example 2 A finely woven non-woven fabric was obtained in the same manner as in Example 1 except that the composite ratio of the polymer A and the polymer B was 80/20. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Example 3 A finely woven non-woven fabric was obtained in the same manner as in Example 1 except that the composite ratio of the polymer A and the polymer B was changed to 40/60. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Example 4 As the polymer A constituting the split fiber, a propylene / ethylene random copolymer II polymerized with a metallocene catalyst shown in Table 2 was prepared and used in the same manner as in the composition of Example 1,
As component B, polyethylene terephthalate (PET; GS300; manufactured by Mitsubishi Chemical Corporation) shown in Table 2 was used, and a composite spinneret in which the fiber cross-sectional shape was alternately divided into 12 segments was used, and the melt volume ratio of polymer A and polymer B was 5
Melt spinning at a ratio of 0:50, stretching, crimping, and 2.2 dsix single fiber (segment fineness of polymer A is about 0.15 dsix, segment fineness of polymer B is about 0.21 dsix) A split fiber having a fiber length of 51 mm was obtained. The obtained split type conjugate fiber short fibers were put on a roller card machine, treated with hot air, and then the basis weight was 60 g /
A nonwoven fabric of m ² was obtained. The obtained non-woven fabric was subjected to high-pressure fluid treatment in the same manner as in Example 1 to obtain a finely woven non-woven fabric. Spinnability,
Table 2 shows the evaluation results of the divided state and the texture of the nonwoven fabric.

Comparative Example 1 As the polymer A, propylene.
A finely woven non-woven fabric was obtained in the same manner as in Example 1 except that the ethylene random copolymer composition IV ^* was used. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Comparative Example 2 A finely woven non-woven fabric was obtained in the same manner as in Example 1 except that the composite ratio of polymer A and polymer B was changed to 10/90. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Comparative Example 3 Propylene / ethylene random copolymer composition IV ^* was used as polymer A, and homopolypropylene (HPP-1; SA03A: manufactured by Nippon Polychem) shown in Table 2 was used as component B. A finely woven non-woven fabric was obtained in the same manner as in Example 1. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Comparative Example 4 As the component B, low density polyethylene (LDP) shown in Table 2 was used.
E; LJ800; manufactured by Nippon Polychem Co., Ltd.)
A finely woven non-woven fabric was obtained in the same manner as in Comparative Example 3. Table 2 shows the evaluation results of spinnability, divided state, and non-woven fabric texture.

Comparative Example 5 As the polymer A, a propylene-based copolymer composition III
Melt spinning was performed in the same manner as in Example 1 except that ^* was used, but the yarn swayed directly under the spinning nozzle, the fusion of the molten fibers became remarkable, and the desired fiber could not be obtained. It was

[0081]

[Table 2]

[0082]

The splittable multi-component composite fiber of the present invention uses a propylene / α-olefin random copolymer polymerized with a metallocene catalyst having a low melting point and a narrow molecular weight distribution,
Since the thermal shrinkage is large, the separation at the interface is ready, and the split conjugate fiber is easy to be ultrafine because the splitting process in the subsequent step (high-pressure liquid flow treatment or the like) is extremely easy. As a result, the low temperature heat sealability after splitting is extremely good,
Since low-temperature fusion bonding is possible and uniform ultrathinning is possible, it is possible to obtain a fiber-formed molded product having a good texture of the obtained nonwoven fabric and a soft texture.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) D04H 1/42 D04H 1/42 K X (72) Inventor Junichi Nishimura 3rd Chidori-cho, Kawasaki-ku, Kanagawa Prefecture No. 1 F-Term in Material Development Center of Nihon Polychem Co., Ltd. BA10B BA10C BA10D DG06A DG06D DG12B DG12C DG13B DG13C DG15A DG15B DG15C DG15D DG20A DG20D GB56 GB66 GB71 JA03A JA03D JA04A JA04D JA06A JA06D JA07A JA07D JB08A JB08D JL00 JL12 YY00A YY00D 4L041 AA07 BA04 BA05 BA09 BB08 BC05 CA42 CA62 DD03 EE10 4L047 AA14 AA21 AA23 AA27 AB02 AB08 BA03 BA04 BA08 CA02 CA04 CA05 CA06 CB01 CB02 CB09 CC04 CC05 CC12

Claims (15)

[Claims] 1. A split-type multi-component composite fiber comprising at least two components of a thermoplastic resin, wherein each component is alternately adjacent in a fiber cross section, wherein one component of the thermoplastic resin is a metallocene catalyst. It is a propylene / α-olefin random copolymer that is polymerized and has the following properties (1) to (6), and the area ratio of the copolymer in the fiber cross section is 20 to 8.
A propylene-based splitting type multi-component composite fiber characterized by being 0%. Characteristic (1): MFR is 20 to 200 g / 10 minutes Characteristic (2): Q value is 2.0 to 4.0 Characteristic (3): Tm is 110 to 135 ° C. Characteristic (4): T ₈₀ -T ₂₀ is 10 ° C or less Characteristic (5): 0 ° C soluble amount of 3% by weight at TREF measurement
The following characteristic (6): α-olefin content is 1 to 18 mol% (however, MFR is 230 ° C. according to JIS-K6921,
Melt flow rate at 21.18 N, Q value is the ratio (Mw / Mn) of weight average molecular weight Mw and number average molecular weight Mn measured by GPC, Tm is a differential scanning calorimeter (DSC)
The peak temperature of the melting curve obtained by T ₈₀ is the temperature at which 80 wt% is eluted in the integrated elution curve obtained by temperature rising elution fractionation (TREF), and T ₂₀ is the temperature at which 20 wt% is eluted. ) 2. The α-olefin of the propylene / α-olefin random copolymer is ethylene, and
The polypropylene-based splittable multi-component composite fiber according to claim 1, wherein the content thereof is 1 to 12 mol%. 3. The thermoplastic resin, wherein the melting point difference between the propylene / α-olefin random copolymer and other components is 10 ° C. or more.
The polypropylene-based splittable multi-component composite fiber according to. 4. A thermoplastic resin, wherein each one of the propylene / α-olefin random copolymer and another component is used.
The polypropylene-based splittable multi-component composite fiber according to any one of claims 1 to 3, wherein a difference in single fiber heat shrinkage at 20 ° C for 10 minutes is 10% or more. 5. The thermoplastic resin, wherein the other component than the propylene / α-olefin random copolymer is a polyethylene resin or a polypropylene resin polymerized by a Ziegler catalyst. The polypropylene-based splittable multi-component composite fiber according to any one of items 1 to 4. 6. The thermoplastic resin, wherein the component other than the propylene / α-olefin random copolymer is a polyester resin or a polyamide resin, according to any one of claims 1 to 5. The polypropylene-based splittable multi-component composite fiber according to. 7. The polypropylene-based splittable multi-component conjugate fiber according to claim 1, wherein the splitting ratio is 75% or more. 8. A fiber molded article using the polypropylene-based splittable multi-component conjugate fiber according to claim 1. Description: 9. The fiber molded article according to claim 8, which is a fiber aggregate. 10. A laminated fiber molded article obtained by laminating a sheet on one side or both sides of the fiber molded article according to claim 8. 11. A laminated fiber molded article obtained by laminating the fiber molded article according to claim 8 or 9 on both sides of a sheet. 12. The sheet is a non-woven fabric, a film, a knit,
The laminated fiber molded article according to claim 10 or 11, which is a sheet selected from at least one kind of woven fabric. 13. An absorbent article using the fiber molded article according to claim 8 or 9, or the laminated fiber molded article according to any one of claims 10 to 12. 14. A wiper using the fiber molded product according to claim 8 or 9, or the laminated fiber molded product according to any one of claims 10 to 12. 15. A battery separator using the fiber molded product according to claim 8 or 9, or the laminated fiber molded product according to any one of claims 10 to 12.