JP2856949B2 - Hydrophilic fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fiber having excellent hydrophilicity, particularly to a heat-adhesive conjugate fiber, and more particularly to a polyolefin fiber having excellent durability and hydrophilicity. In particular, it relates to a heat-adhesive conjugate fiber.

[0002]

2. Description of the Related Art Thermo-adhesive fibers for producing non-woven fabrics and the like by heat fusion between fibers are known. For example, there are a polyethylene-polypropylene conjugate fiber having polyethylene as an adhesive component, a conjugate fiber with polypropylene having a copolymerized nylon as an adhesive component, or a conjugate fiber with polyethylene terephthalate having an ethylene-vinyl alcohol copolymer as an adhesive component. .

[0003] Particularly recently, baby diapers and diaper liners,
Non-sanitary materials such as sanitary materials such as sanitary products, countercloths for the restaurant industry, drainage bags for kitchenware sinks, and medical fields such as base cloth and fixing sheets for shipping drugs, hospital surgical gowns, masks, etc. Nonwoven fabrics have been widely used. Among these many non-woven products, especially for baby diapers, sanitary products, and the like, a more durable hydrophilic property than conventional ones has been required. However, most of the conventional methods are based on a post-processing method of surface treatment with an oil agent, etc., which has the initial performance, but the surface oil agent falls off after a certain amount of use, resulting in extremely low performance. There were many.

[0004] Above all, in the case of wet-type nonwoven fabrics for diaper surface materials and sanitary pad surface materials, the papermaking process must be performed in water during the manufacturing process. The hydrophilizing agent falls off, and only a product which does not have sufficient performance is obtained in the final product. In addition, when a hydrophilic material such as wood pulp or rayon is mixed and mixed, if the heat-fusible fiber is hydrophobic, the resulting nonwoven fabric or sheet loses hydrophilicity.

[0005] When a polyolefin containing polyethylene as a main component is used as an adhesive component, a light-weight, soft-feel nonwoven fabric can be obtained. However, since it is hydrophobic, there are many problems in the above-mentioned applications. Therefore, fibers in which an appropriate wetting agent is added to the fibers constituting the nonwoven fabric have come to be manufactured so that water can quickly penetrate into the nonwoven fabric. The conjugate fiber is known in JP-B-61-10583 and JP-A-63-92723, and the fiber having a wetting agent is known in JP-A-60-194113. And there is a problem in the fiberization process, and there is a problem that the physical properties of the fiber are insufficient and are not yet practically sufficient.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention relates to a heat-fusible fiber using a polyolefin-based polymer as an adhesive component, preferably a polyolefin containing polyethylene as a main component, especially a heat-fusible conjugate fiber. In, while maintaining sufficient fiber physical properties such as fiber strength, and sufficient adhesive strength, for both the obtained dry non-woven fabric and wet non-woven fabric, a fiber with extremely excellent hydrophilic durability It is to provide without trouble.

Another object of the present invention is to provide a non-woven fabric or sheet made of heat-fusible fibers using a hydrophilic material such as wood pulp, viscose rayon or vinylon. An object of the present invention is to provide a heat-fusible fiber having excellent hydrophilic durability and exhibiting more hydrophilicity without impairing the hydrophilicity of the hydrophilic material. Another object of the present invention is to provide a hydrophilic fiber that can be used not only for heat fusion but also for heat fusion.

[0008]

The fiber of the present invention comprises a compound in which a group having a polyalkylene oxide chain is bonded to a polyalkylenepolyamine-based skeleton and which satisfies a specific condition is a polyolefin-based compound. A durable hydrophilic fiber contained in a polymer, in particular, the compound is dispersed in a polyolefin containing polyethylene as a main component, and the polyolefin is used as a sheath component.
A heat-adhesive conjugate fiber having a durable hydrophilic property, which is a conjugate fiber using the above thermoplastic polymer as a core component. That is, the present invention relates to a compound in which a group having a polyalkylene oxide chain is bonded to a polyalkylenepolyamine-based skeleton, has an HLB in the range of 6.0 to 16.0, an average molecular weight of 5,000 or more, and an amine value of Heat-fusible composite, comprising a polyolefin-based fiber containing 0.1 to 20% by weight of a compound having a molecular weight of 500 or less, in particular, the compound is contained in the polyolefin sheath component in the above amount. Fiber.

To explain the present invention more specifically, a compound (hereinafter, abbreviated as N-POA compound) having a group having a polyalkylene oxide chain bonded to a polyalkylene polyamine skeleton used in the present invention is known. For example, JP-A-58-80391 describes that the compound can be used as a dispersant for a coal slurry.

The N-POA compound can be produced according to a general method for producing a surfactant. For example, it can be obtained by blowing an alkylene oxide gas into a heated polyalkylene polyamine skeleton compound containing an alkali catalyst such as caustic soda. The polyalkylene polyamine compound serving as a skeleton can be obtained by reacting alkylene polyamines or a compound thereof with a compound such as urea. Therefore, the polyalkylene polyamine-based skeleton compound may contain a group other than an alkylene group, an amino group, and an imino group, such as a carbonyl group.

The group having a polyalkylene oxide chain is preferably bonded to a nitrogen atom of the polyalkylene polyamine skeleton. Therefore, the N-POA compound used in the present invention includes a case where substantially all of the hydrogen atoms of the amino group and the imino group are substituted with a group having a polyalkylene oxide chain.

The N-POA compound has a molecular weight of 5,
000 or more is required, and preferably 10,000 or more and 100,000 or less. When the molecular weight is too low, the surface bleeding property after kneading and dispersing a polyolefin such as polyethylene becomes severe, and the durability as a hydrophilizing agent becomes slightly insufficient. In particular, in the case of a form having a large surface area such as a fiber, this phenomenon occurs as a remarkable phenomenon. On the other hand, if the molecular weight is too low, the compatibility with the polyolefin becomes poor, the spinnability during spinning becomes poor, and single yarn breakage and yarn breakage occur. Of course, two or more N-POA compounds having different molecular weights, amine values, HLB values and the like may be used in combination.
Suitable structures for the N-POA compound include amine moieties,
That is, it is a polymer in which an oxyethylene unit and an oxypropylene unit are randomly or block copolymerized with an amino group or an imino group. An example of the structural formula is shown below.

[0013]

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Here, R ↓ 1 to R ↓ 7 are a group having a polyalkylene oxide chain or a hydrogen atom. However, R ↓
Regarding 3, as is apparent from the above formula (1), [n] × [x] are present in one molecule, but they need not be the same. Also, R ↓ 2, R ↓
As for 4, R ↓ 5, there will be [x] pieces in one molecule, but these R ↓ 2, R ↓ 4, R ↓ 5 need not be the same. N of the polyamine molecular chain forming the skeleton is preferably from 0 to 10, particularly preferably from 0 to 5. If n is too large, the original effect of the polyolefin as a kneading agent for imparting water absorption will be insufficient. X is 1
~ 20, particularly preferably 1 ~ 5. If x is too large, the fibers tend to be colored during spinning.

In the group having a polyalkylene oxide chain of R ↓ 1 to R ↓ 7, it is necessary that an oxyethylene unit and an oxypropylene unit be present (provided that an oxyethylene unit and an oxyethylene unit are present in the same group). It is not necessary that propylene units be present, i.e., groups having one polyalkylene oxide chain may have only oxyethylene units, and groups having another polyalkylene oxide chain may have only oxypropylene units. Good), depending on the composition ratio of the oxyethylene unit and the oxypropylene unit, the hydrophilicity with respect to water may decrease, so that the oxyethylene unit is the main component within a range not to impair the object of the present invention. Is more preferred. As a guide for judging a preferable range, it is good to judge by the HLB value. As a group having a more preferable polyalkylene oxide chain, a structure represented by the following formula 2, in which an oxypropylene unit (PO) is bonded in a block shape from an N atom, and further an oxyethylene unit (EO) is bonded in a block shape, is preferable.

[0016]

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The HLB value is a method of expressing the balance between the hydrophilic group and the lipophilic group of a surfactant, and is a method used in 1940 Crif.
Hydrofile Lipoph announced by fin
ile Balance, but the HLB value is HLB
Value = 20 × M ↓ H / M (M: molecular weight of surfactant, M ↓ H: molecular weight of hydrophilic group portion) HLB = 0 when the amount of hydrophilic group in the molecule is 0% and H when the amount of hydrophilic group in the molecule is 100%.
LB = 20, HL when hydrophilic group and lipophilic group are equal
B = 10. In the case of the N-POA compound of the present invention,
An oxyethylene unit was used as a hydrophilic group, and an oxypropylene unit was used as a lipophilic group. The HLB value is determined excluding the polyamine portion of the skeleton.

The H of the N-POA compound used in the present invention
The range of the LB value is 6.0 to 16.0. HLB value is 1
If it is higher than 6.0, N
-The initial water absorption performance after fiberization by adding the POA compound is sufficiently exhibited, but the durability becomes insufficient. In particular, the washing durability becomes insufficient, and the water absorption performance after washing decreases. This is because the hydrophilic element of the N-POA compound becomes too strong, so that the N-POA compound dispersed in the polyolefin is eluted during washing, and as a result, the water absorption performance as a fiber is reduced. It is thought to be. On the other hand, when the HLB value is lower than 6.0, the hydrophobic element of the N-POA compound becomes too strong, so that it is satisfactory as the provision of water absorption performance to the original polyolefin fiber. Not at the level.

The terminal of the group having a polyalkylene oxide chain may be a hydroxyl group, may be blocked with a non-ester-forming organic group, or may have an ether bond, an ester bond,
It may be bonded to another ester-forming organic group by a carbonate bond or the like. Further, atoms other than the ethylene oxide unit and the propion oxide unit may be present in the group or at the root of the group.

Further, all amino groups of the polyamine skeleton,
It is not necessary that a group having a polyalkylene oxide chain is bonded to the imino group, and an unreacted free amino group or imino group may be present. However, the presence of too many free amino groups and imino groups is not preferable because toxicity to the human body increases. In particular, when an N-POA compound is added to the fiber and used for applications that directly contact the skin of the human body, it is necessary to pay attention to the problem of skin damage. From such a point, the N-POA compound of the present invention needs to have an amine value of 500 or less. Preferably it is 100 or less. The amine value is the number of milligrams calculated by converting the amount of acid required to neutralize 1 g of the compound with KOH.

The polyalkylenepolyamine structure constituting the skeleton of the N-POA compound has a plurality of alkylene groups and a plurality of nitrogen atoms, and the alkylene groups include lower groups such as ethylene and propylene. Alkylene groups are common. If the skeleton has only one alkylene group or has only one amino group or imino group, the N-POA compound has low affinity for polyolefin, and the object of the present invention is to Not achieved.

Although the reason why the N-POA compound used in the present invention is extremely excellent in imparting the durability and hydrophilicity of the polyolefin fiber is not necessarily clear, the polyalkylenepolyamine skeleton has excellent affinity with the polyolefin, The ethylene oxide unit in the side chain is excellent in hydrophilicity (wetability), and the propylene oxide unit in the side chain is NP
It has a control function to balance the elution resistance and hydrophilicity of OA. As a result, it is considered that the OA has good wettability to water and has extremely excellent durability. This is because the compound in which a propylene oxide unit is first added as a side chain to the polyamine skeleton in the above formula 1, and an ethylene oxide unit is added to the end of the side chain is most preferable as an N-POA compound. Predictions are supported.

The content of the N-POA compound described above in the polyolefin polymer ranges from 0.1% by weight to 2%.
The range is 0% by weight. If it is less than 0.1% by weight, the desired water absorption is insufficient. If it exceeds 20% by weight, spinnability will be poor. It may also contain an antioxidant. In particular, when a polymer having a high melting point such as polyethylene terephthalate is used as the other polymer of the composite component, the spinning temperature is increased, and the polyoxyalkylene glycol portion is easily oxidized and thermally decomposed. It is effective to add a dirt phenol-based antioxidant to form a fiber.

The polyolefin referred to in the present invention is mainly composed of polyethylene or polypropylene.
Polyethylene is preferred from the viewpoint of heat fusion properties, and general ordinary polyethylene can be used. As polyethylene, mainly low-density polyethylene (abbreviated as LDPE),
Medium density polyethylene or high density polyethylene (HD
PE) or linear low density polyethylene (LLD)
PE (abbreviated as PE). Polyolefin is N-PO
Excellent affinity with A and excellent hydrophilicity are obtained.

As described above, the fiber of the present invention is preferably a composite fiber having a sheath component of a polyolefin mainly composed of polyethylene containing an N-POA compound and a core component of another melt-spinnable polymer. Used. It has been found that a composite fiber structure is best for maintaining the purpose of a heat-bondable and durable hydrophilic nonwoven fabric and a good fiber process.

As the other composite spinning component (core component), a thermoplastic polymer having a melting point of 150 ° C. or more is used. Examples thereof include polyethylene terephthalate, polybutylene terephthalate, nylon-6, nylon-6,6, and polypropylene. Etc. In order to achieve a sufficient purpose as an adhesive fiber, N-
The proportion occupied by the POA compound-containing polyolefin component, that is, the fiber cross-sectional circumference is preferably 50% or more. On this occasion,
When importance is attached to the morphological stability of the adhesive fiber, it is needless to say that other composite spinning components must use a thermoplastic polymer having a melting point higher than the bonding processing temperature.

A specific example of the cross-sectional shape of the composite form of the core-in-sheath type conjugate fiber of the present invention will be described with reference to the drawings. A complete core-in-sheath type conjugate fiber as shown in FIG. 1 and FIGS. A core / sheath composite fiber having a core component having an irregular shape, a multicore sheath / composite fiber as shown in FIG. 4, an eccentric core / sheath composite fiber as shown in FIG. 6, a modified cross-section core / sheath composite fiber as shown in FIG. Laminated conjugate fibers are also included. The component (a) in FIGS. 1 to 8 is a polyolefin containing an N-POA compound, and the component (b) has a melting point of 150.
It is a thermoplastic polymer having a temperature of at least C. Approximately 5 perimeter of fiber cross section
It is desirable that 0% or more be occupied by the component (a) polymer. If it is less than 50%, it is difficult to obtain a good durable hydrophilic property and a heat-adhesive fiber for the purpose of the present invention. The composite ratio of the sheath component and the core component must be in the range of 80:20 to 20: 80% by weight. If the content of the sheath component is less than 20% by weight, good hydrophilicity and good thermal adhesiveness, which are the objects of the present invention, become insufficient, which is not preferable. On the other hand, when the content exceeds 80% by weight, the processability such as spinnability and stretchability deteriorates,
It is not preferable because the A rating decreases.

The fiber of the present invention is also used as a fusion-bonded fiber assembly consisting of only a composite fiber of an N-POA compound-containing polyolefin and another polymer.
It is also used as a fiber bundle treated by mixing and fusion with other fibers containing not less than% by weight.

The fiber aggregate cut particularly to 20 to 100 mm is used as a non-woven fabric binder for a dry process, and 3 to 1 mm.
A nonwoven fabric cut to 0 mm is suitable as a nonwoven fabric binder for a wet process, and a nonwoven fabric having high strength, durable hydrophilicity, and moisture and heat resistance can be obtained. Further, even when a hydrophobic polyester such as polyethylene terephthalate or polybutylene terephthalate is used as other fibers that can be mixed, the significance of the present invention is that sufficient nonwoven fabric strength and excellent durable hydrophilicity can be exhibited. large. Further, when a hydrophilic material such as wood pulp, rayon, or vinylon is used as the fiber to be mixed, the hydrophilicity can be more positively exhibited as well as not hindering the hydrophilicity.

Although the heat-fused fiber aggregate referred to in the present invention is useful for a wide variety of nonwoven fabrics for various uses, it is a very significant feature that it exhibits a remarkable effect especially for wet nonwoven fabrics. As a specific application, for example, a sanitary material application requiring hydrophilicity is suitable.

The excellent hydrophilicity as referred to in the present invention can be determined by making the fibers into a non-woven fabric, and then observing the water absorption rate and the repeated liquid absorption rate. More specifically, the liquid absorption rate is about 4 times that of the cotton-like material of the fiber to be measured.
After preparing a non-woven fabric of 0 g / m @ 2, 0.2 g of water colored with red ink was dropped on a plastic dish, and a sample of 5 cm x 5 cm of the non-woven fabric piece was placed on the red ink and removed after 1 second. The weight of the liquid absorbed by the sample at that time is measured. The liquid absorption weight after the measurement was divided by the weight of the nonwoven fabric sample before the measurement to obtain the liquid absorption. The non-woven fabric is prepared by mixing a mixed cotton containing a predetermined weight or more of the sample raw cotton to be measured through a miniature card to prepare a web having a basis weight of 40 g / m @ 2, and then forming a 5 m web.
/ Min at a flow rate of 30 kg / cm ↑ 2, air-dry, and further dried at 150 ° C with an auto dryer.
A non-woven fabric for measuring hydrophilicity was heat-treated under the condition of lower one minute.

The liquid absorption was measured by n = 10, and the average value was taken as the liquid absorption. The measurement of the liquid absorption rate was repeated by measuring the liquid absorption rate until water spread over the entire surface of the sample nonwoven fabric piece 5 cm x 5 cm when the piece was dropped on the water surface, and the hydrophilic performance was evaluated. Carried out.

The water absorption as measured by the above method is less than 200% in the case of ordinary polyethylene heat-fusible fibers. On the other hand, it was confirmed that the fiber of the present invention usually had a liquid absorption of 300% or more, and exhibited a liquid absorption of 500% or more when the amount of the N-POA compound added was large. In addition, the performance hardly deteriorated even after the washing treatment for 10 times. On the other hand, when a water-absorbing agent is surface-treated on ordinary polyethylene heat-fusible fibers, the initial performance may be 200% or more, but is considerably reduced after 10 times washing.

Comparing the liquid absorption rate repeatedly, the ordinary hydrophobic synthetic fiber is longer than 60 seconds, whereas the fiber of the present invention shows a liquid absorption rate of 60 seconds or less. When the amount of the N-POA compound added was large, it was recognized that the liquid absorption rate was almost instantaneous. And 10
The performance hardly deteriorated even after repeated washing.

The fibers having such hydrophilic properties can be prepared by adding an appropriate amount of an N-POA compound and selecting appropriate fiberizing conditions to obtain the surprising hydrophilic properties of the present invention such as those of the present invention. Is obtained. Further, in the present invention, the aforementioned N-POA
By incorporating the compound into the polyolefin, a hydrophilic polyolefin fiber is obtained. Such a fiber can be used in fields other than the application for heat fusion, and the conjugate fiber as described above can be used in such a field.

[0036]

Next, the present invention will be described with reference to examples. The washing treatment in the examples was performed according to the JISL0217-103 method. A synthetic detergent for clothing is added and dissolved at a rate of 2 g in 1 liter of water at a liquid temperature of 40 ° C. to prepare a washing liquid. A sample and a load cloth are introduced into the washing liquid so that the bath ratio becomes 1:30, and the operation is started. After treating for 5 minutes, the operation was stopped, the sample and the load cloth were dehydrated with a dehydrator, and then the washing liquid was replaced with fresh water at room temperature, rinsed for 2 minutes at the same bath ratio, and then dehydrated. Rinse for a minute and air dry. The above operation was repeated 10 times to obtain a measurement sample after 10 times.

[Examples 1 to 3] An HDPE (Yukaron Hard JX-10) having a MI value of 20 from Mitsubishi Kasei Co., Ltd. was melted, and N-polyoxyalkylenepoly represented by the following chemical formula 3 was added into the molten polymer. An alkylene polyamine compound,
After adding a predetermined amount of a hindered phenol-based antioxidant having an HLB of 12.0 and an average molecular weight of about 50,000, the mixture was uniformly mixed by a static mixer, and then kept at 290 ° C. The intrinsic viscosity [η] measured at 30 ° C. in a mixed solution of an equal amount of phenol and tetrachloroethane was supplied to the spinning head as a sheath component, and the intrinsic viscosity [η] was 0.62 dl.
/ G of polyethylene terephthalate as a core component, and core / sheath composite spinning having a cross section of FIG. 1 was performed at a core / sheath = 50/50 weight ratio. Extruded from a round nozzle at 290 ° C,
It was wound up at 1000 m / min. The obtained raw yarn is stretched 390% in a water bath at 75 ° C., then contracted by 8% in a water bath at 95 ° C., mechanically crimped, and oil solution mainly containing an ethylene oxide adduct of stearyl phosphate is added. 0.1 wt%, heat-relaxed at 150 ° C. for 10 minutes, and cut to a length of 51 mm into single fiber denier 2 cotton. The fiberization processability was good and there was no particular problem.

[0038]

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Thereafter, the cotton is formed into a fiber web through a guard and a random webber. The fiber web is entangled by applying a high-pressure jet of 30 kg / cm @ 2 from a nozzle to obtain a fiber entanglement having an average basis weight of 40 g / m @ 2. A synthetic nonwoven was obtained. The measurement of the liquid absorption rate and the repetitive liquid absorption rate of the nonwoven fabric were carried out in the standard state (20
C., 65% RH). The results are shown in (1) of Table 1. It can be seen from Table 3 (3) that a durable fiber having good hydrophilicity was obtained.

[Comparative Example 1] A fiber was prepared in the same manner as in Example 1 except that the HDPE component contained no hydrophilic agent.
A nonwoven fabric was prepared using the cotton in the same manner as in Example 1, and the performance was examined.

[Examples 4 and 5] As the additives, those having the same molecular structure as in Chemical formula 3 but different HLB values were used. Example 4 has HLB = 7.0, and Example 5 has HLB = 7.0.
LB = 15.0 was used. Otherwise, the procedure was the same as in Example 1. In all cases, fibers having good hydrophilicity and good durability were obtained.

Examples 6 to 8 The same procedures as in Example 1 were carried out except that the additives used had the same molecular structure as in Chemical formula 3, but had a different average molecular weight. As a result, a fiber having good fiberization processability and durability and good hydrophilicity was obtained.

[Examples 9 to 14] In Examples 9 and 10, the core-sheath composite ratio was changed, in Examples 11 and 12, the fiber cross-sectional shape was changed, and in Example 13, polybutylene terephthalate was used as the core component polymer. Example 14 was performed in the same manner as Example 1 except that nylon 6 was used. In each case, it was found that the fiberization processability was good and the hydrophilic performance was also maintained at a good level.

Examples 15 and 16 In Example 15, LDPE (Sumitomo Chemical Sumikasen G-8) was used as a sheath component polymer.
04), and Example 16 was carried out in the same manner as in Example 1, except that LLDPE (Mitsubishi Yuka Yucalon LL M40F) was used. In each case, it was found that the fiberization processability was good and the hydrophilic performance was also maintained at a good level.

Example 17 The same procedure as in Example 1 was carried out except that an additive having a molecular structure of Chemical Formula 4 was used as an additive.

[0046]

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In the formula, R ↓ 1 to R ↓ 7 are random copolymers of PO and EO, having an HLB of 12.0 and an average molecular weight of about 20,000. The fiberization processability was good, and a durable fiber having good hydrophilicity was obtained.

[Comparative Example 2] After adding about 1.5 wt% of a polyvinyl alcohol-based moisture absorbing agent to the raw cotton of Comparative Example 1, a nonwoven fabric was prepared in the same manner as in Example 1, and the water absorption performance was measured. is there. Although good water absorption was observed at the raw cotton stage after the application of the moisture absorbent, the initial performance and the performance after the washing treatment of the nonwoven fabric after the hydroentanglement treatment were significantly reduced.

[Comparative Example 3] The same N-POA compound as in Chemical formula 3, but with a small amount of a hindered phenolic antioxidant added, was added to HDPE in NPE amount of 25.0.
In this case, the kneading was carried out under the same conditions as in Example 1 except that the kneading was carried out so as to be wt%. However, the viscosity was greatly reduced during spinning, and stable spinning could not be performed.

[Comparative Example 4] An additive having the same structure as that of Chemical formula 3 and a molecular weight of about 3,000 was used. However, the viscosity was drastically reduced during spinning, and the screws dropped, single yarn breakage and breakage occurred frequently, and stable spinning could not be performed.

Comparative Example 5 An additive having the same structure as that of Chemical formula 3 but having HLB = 5.0, that is, a hydrophobic group-rich PO segment was used.
Was performed in the same manner as described above. Although the fiberization processability was good, the level of hydrophilic performance was insufficient.

Comparative Example 6 An additive having the same structure as that of Chemical formula 3 but having an HLB = 18.0, that is, an EO segment-rich hydrophilic group was used, and the other additives were the same as in Example 1. The method was performed. The fiberization processability was good, but the hydrophilic performance was good at the initial performance, but poor after washing.

[Comparative Examples 7 and 8] N-POA as a kneading agent
A conjugate fiber was produced in the same manner as in Example 1 except that an EO-PO block copolymer (Comparative Example 8) or an EO / PO random copolymer (Comparative Example 9) was used instead. And the water absorption performance was measured. The results were inferior in durable hydrophilicity, as is clear from (3) in Table 1.

[0054]

[Table 1]

[Table 2]

[Table 3]

[0055]

As described above, the present invention relates to a durable hydrophilic heat-fusible conjugate fiber having a durable and good hydrophilic property and a conjugate fiber by incorporating a specific hydrophilizing agent into a polyolefin. An object of the present invention is to provide a nonwoven fabric which is partially or entirely used.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a cross-sectional shape of a conjugate fiber of the present invention.

FIG. 2 is a view showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 3 is a view showing still another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 4 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 5 is a diagram showing an example of a cross-sectional shape of the conjugate fiber of the present invention.

FIG. 6 is a view showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 7 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 8 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

[Explanation of symbols]

B: Sheath component composed of polyolefin B: Core component composed of a thermoplastic polymer having a melting point of 150 ° C. or higher

Claims (2)

(57) [Claims] 1. A compound in which a group having a polyalkylene oxide chain is bonded to a polyalkylene polyamine-based skeleton, having an HLB in the range of 6.0 to 16.0, an average molecular weight of 5,000 or more, and an amine value. Is a polyolefin-based fiber containing 0.1 to 20% by weight of a compound having a molecular weight of 500 or less. 2. A compound having a group having a polyalkylene oxide chain bonded to a polyalkylene polyamine skeleton, having an HLB in the range of 6.0 to 16.0, an average molecular weight of 5,000 or more, and an amine value. Is a sheath component composed of a polyethylene as a main component containing 0.1 to 20% by weight of a compound having a melting point of 500 or less.
A conjugate fiber comprising a thermoplastic polymer at 0 ° C. or higher as a core component, and a weight ratio of the sheath component to the core component is 20:80 to 80:20.