TWI692497B - Additive for polyolefin resin, polyolefin resin composition, polyolefin synthetic fiber nonwoven fabric, and method of producing polyolefin synthetic fiber nonwoven fabric - Google Patents

Abstract

The additive for polyolefin resin of the present invention is characterized by containing the following fatty alcohol and the following oxyethylene alkyl ether. The fatty alcohol is a monovalent fatty alcohol having 16 to 32 carbon atoms. The oxyethylene alkyl ether is a compound in which the ethylene oxide is added at a ratio of less than 2 moles to a monovalent fatty alcohol having a carbon number of 12 to 26 in 1 mole.

Description

Additive for polyolefin-based resin, polyolefin-based resin composition, polyolefin-based synthetic fiber nonwoven fabric, and method for producing polyolefin-based synthetic fiber nonwoven fabric

In particular, the present invention relates to additives for polyolefin-based resins, polyolefin-based resin compositions, polyolefin-based synthetic fiber nonwovens, and polyolefin-based synthetic fiber nonwovens that can exhibit hydrophilicity immediately after its production. Manufacturing method.

In general, as sanitary products such as paper diapers, there are known products in which the surface of a superabsorbent polymer is covered with polyolefin-based synthetic fibers in order to absorb body fluids. Synthetic fibers covering the surface of superabsorbent polymers are required to have excellent absorption characteristics such as hydrophilicity, point absorption, and durable hydrophilicity that absorbs body fluids repeatedly and quickly. In order to respond to these requirements, additives for polyolefin-based resins may be used in combination with polyolefin-based resins. For example, Patent Document 1 applies an alkylene oxide such as ethylene oxide of 2 to 10 moles to a hydrocarbon group having 22 to 40 carbon atoms as an additive for a polyolefin resin used in combination with a polyolefin resin. The addition of ether compounds was revealed.

Patent Literature 1: Japanese Special Publication No. 2004-523666

However, in the case of using the conventional additive for polyolefin-based resin, there is a problem that the polyolefin-based synthetic nonwoven fabric does not exhibit hydrophilicity immediately after its production.

The problem to be solved by the present invention is to provide an additive for polyolefin-based resin, a polyolefin-based resin composition, a polyolefin-based synthetic fiber non-woven fabric, and a polyolefin-based synthetic fiber non-woven fabric that can exhibit hydrophilicity immediately after its manufacture Manufacturing method of polyolefin-based synthetic fiber nonwoven fabric.

The present inventors conducted studies to solve the above-mentioned problems, and as a result, they found that additives for polyolefin-based resins containing specific fatty alcohols and specific oxyethylene alkyl ethers are just right.

In order to achieve the above object, one aspect of the present invention provides an additive for a polyolefin-based resin, which is characterized by containing the following fatty alcohol and the following oxyethylene alkyl ether. Fatty alcohol is a monovalent fatty alcohol with 16 to 32 carbon atoms. Oxyethylene oxide alkyl ether is a compound which adds ethylene oxide at an average ratio of less than 2 moles to 1 mole of fatty alcohol with a carbon number of 12 to 26.

Preferably, the fatty alcohol is a monovalent fatty alcohol having 18 to 26 carbon atoms.

Preferably, the oxyethylene alkyl ether is a compound in which 1 mol of monovalent fatty alcohol having a carbon number of 16 to 24 is added with ethylene oxide at an average ratio of less than 2 mol.

Preferably, the oxyethylene alkyl ether is a compound in which ethylene oxide is added at an average ratio of not more than 1.5 moles for 1 mole of the monovalent fatty alcohol.

Preferably, if the content ratio of the fatty alcohol and the oxyethylene alkyl ether is 100% by mass, the additive for polyolefin-based resin contains the fatty alcohol at a ratio of 1 to 70% by mass and 30 to 99% by mass. The proportion contains the oxyethylene alkyl ether.

Preferably, the additive for polyolefin-based resin further contains the following fatty acid derivative. Fatty acid derivatives are selected from the group consisting of ester compounds of monocarboxylic acids and monohydric fatty alcohols with carbon numbers 16-24, ester compounds of monocarboxylic acids and polyhydric fatty alcohols with carbon numbers 16-24, and fatty amides with carbon numbers 16-24 At least one compound.

Preferably, if the content ratio of the fatty alcohol, the oxyethylene alkyl ether, and the fatty acid derivative is 100% by mass, the additive for the polyolefin-based resin contains the fatty alcohol at a ratio of 10 to 40% by mass. The oxyethylene alkyl ether is contained in a ratio of 30 to 80% by mass, and the fatty acid derivative is contained in a ratio of 1 to 45% by mass.

Preferably, the polyolefin-based resin is a resin for polyolefin-based synthetic fibers.

Furthermore, in another aspect of the present invention, a polyolefin-based resin composition is provided, characterized in that, if the content ratio of the additive for polyolefin-based resin and the polyolefin-based resin is 100% by mass, the ratio is 1 The additive contains ~70% by mass and the resin contains 30~99% by mass.

Furthermore, in another aspect of the present invention, there is provided a polyolefin-based synthetic fiber nonwoven fabric characterized in that the polyolefin-based synthetic fiber contains the additive for polyolefin-based resin in a ratio of 1.0 to 7.0% by mass.

Furthermore, in another aspect of the present invention, there is provided a method for manufacturing a polyolefin-based synthetic fiber nonwoven fabric, which includes the step 1 of mixing the additive for a polyolefin-based resin with a polyolefin-based resin to obtain a resin composition. Using the obtained resin composition, a step 2 of spinning a polyolefin-based synthetic fiber and a step 3 of joining the polyolefin-based synthetic fiber to form a nonwoven fabric are performed.

Preferably in step 1, the polyolefin-based resin additive and the polyolefin-based resin are mixed to contain the polyolefin-based resin additive in a ratio of 1.0 to 7.0% by mass in the polyolefin-based synthetic fiber.

According to the present invention, especially the polyolefin-based synthetic fiber nonwoven fabric can exhibit hydrophilicity immediately after its manufacture.

(First embodiment)

First, the first embodiment in which the additive for polyolefin-based resin of the present invention (hereinafter also simply referred to as additive) is embodied will be described. The additive of this embodiment contains the following fatty alcohol and the following oxyethylene alkyl ether.

Fatty alcohol is a monovalent fatty alcohol with 16 to 32 carbon atoms.

Oxyethylene oxide alkyl ether is a compound which adds ethylene oxide at an average ratio of less than 2 moles to 1 mole of fatty alcohol with a carbon number of 12 to 26.

As the fatty alcohol having 16 to 32 carbon atoms as the fatty alcohol for the additive of the present embodiment, one kind may be used alone, or two or more kinds may be used in combination. Those with a carbon number of 18 to 26 are preferred. By setting the carbon number to 16 or more, the effect of the present invention can be improved (that is, the polyolefin-based synthetic fiber nonwoven fabric can exhibit high hydrophilicity immediately after its production). In addition, when manufacturing a nonwoven fabric, for example, when manufacturing a nonwoven fabric using a spin-bonding method, it is possible to reduce smoke more. In addition, the durable hydrophilicity of the non-woven fabric can be further improved. On the other hand, by setting the carbon number to 32 or less, the effect of the present invention can be enhanced. In addition, the point water absorption and durable hydrophilicity of the nonwoven fabric can be further improved.

Specific examples of the monovalent fatty alcohol having 16 to 32 carbon atoms include hexadecyl alcohol, octadecyl alcohol, octadecenyl alcohol, Isooctadecyl alcohol, eicosanediol, tetracosyl alcohol, triacontyl alcohol, etc. Specific examples of the monohydric alcohol having 18 to 26 carbon atoms include, for example, stearyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, and tetracosyl alcohol.

The oxyethylene alkyl ether used for the additive of this embodiment is a monovalent fatty alcohol having a carbon number of 12 to 26 as described above, and ethylene oxide is added at an average ratio of less than 2 moles Compound. The oxyethylene alkyl ether may be used alone or in combination of two or more. Among these, it is preferable to add a compound of ethylene oxide to an average molar ratio of less than 2 moles to a monohydric fatty alcohol having a carbon number of 16 to 24. By setting the carbon number to 12 or more, the effect of the present invention can be improved. In addition, when manufacturing a nonwoven fabric, for example, when manufacturing a nonwoven fabric using a spin-bonding method, it is possible to reduce smoke more. In addition, the durable hydrophilicity of the non-woven fabric can be further improved. In addition, by setting the carbon number to 26 or less, the effect of the present invention can be enhanced. In addition, the point water absorption and durable hydrophilicity of the nonwoven fabric can be further improved. The number of addition moles of ethylene oxide of the oxyethylene alkyl ether provided for the additive of this embodiment is less than 2.0 moles on average, preferably less than 1.5 moles on average. By adding ethylene oxide at an average ratio of less than 2.0 moles, the effect of the present invention can be improved. In addition, when manufacturing a nonwoven fabric, for example, when manufacturing a nonwoven fabric using a spin-bonding method, it is possible to reduce smoke more and to improve the uniformity of additives.

Specific examples of monohydric fatty alcohols having a carbon number of 12 to 26 as raw materials for oxyethylene alkyl ethers include, for example, dodecanol, tridecyl alcohol, isotridecyl alcohol, tetradecyl alcohol, cetyl alcohol, and stearyl alcohol. , Octadecenol, isooctadecyl alcohol, behenyl glycol, tetracosyl alcohol, hexacosanol, etc. Specific examples of the monovalent fatty alcohol having 16 to 24 carbon atoms include cetyl alcohol, stearyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, and tetracosyl alcohol.

In the additive of the present embodiment, the content ratio of the fatty alcohol and oxyethylene alkyl ether in the additive is not particularly limited. The additive of this embodiment preferably contains fatty alcohol at a ratio of 1 to 70% by mass if the total content ratio of the fatty alcohol and oxyethylene alkyl ether is 100% by mass. And it contains oxyethylene alkyl ether at a ratio of 30 to 99% by mass. By specifying within the above range, the effect of the present invention can be further enhanced.

The additive of the present embodiment preferably contains the following fatty acid derivative. Fatty acid derivatives are selected from the group consisting of ester compounds of monocarboxylic acids and monohydric fatty alcohols with carbon numbers 16-24, ester compounds of monocarboxylic acids and polyhydric fatty alcohols with carbon numbers 16-24, and fatty amides with carbon numbers 16-24 At least one compound. These fatty acid derivatives may be used alone or in combination of two or more. By blending the fatty acid derivative, when manufacturing a nonwoven fabric, for example, when manufacturing a nonwoven fabric using a spinning bonding method, smoke can be further reduced.

Examples of the monocarboxylic acid having 16 to 24 carbon atoms used as the raw material of the fatty acid derivative include hexadecanoic acid, octadecanoic acid, octadecenoic acid, isooctadecanoic acid, behenic acid, and diacid. Fourteen acid and so on.

Examples of the monobasic fatty alcohol used as the raw material of the above fatty acid derivatives include methanol, ethanol, propanol, butanol, hexanol, octanol, dodecanol, tridecanol, isotridecyl alcohol, tetradecyl alcohol, and decyl alcohol. Hexanol, stearyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, tetracosyl alcohol, hexacosanol, etc.

Examples of the polyhydric fatty alcohol used as the raw material of the fatty acid derivative include ethylene glycol, propylene glycol, glycerin, neopentyl alcohol, sorbitol, and sorbitan.

Examples of fatty amides having 16 to 24 carbon atoms include hexadecanoic acid amide, octadecanoic acid amide, octadecenoic acid amide, and isodecanoic acid amide. Isooctadecanoic acid amide, docosanoic acid amide, docosenoic acid amide, tetracosanoic acid amide, etc.

In the additive of the present embodiment, the content ratio of the fatty alcohol, oxyethylene alkyl ether, and fatty acid derivative in the additive is not particularly limited. The additive of the present embodiment preferably has the content of the fatty alcohol, oxyethylene alkyl ether, and fatty acid derivative totaling 100% by mass. The fatty alcohol is contained at a ratio of 10 to 40% by mass, the oxyethylene alkyl ether is contained at a ratio of 30 to 80% by mass, and the fatty acid derivative is contained at a ratio of 1 to 45% by mass. By specifying within the above range, the effect of the present invention can be further enhanced.

The use of the polyolefin resin to which the additive of this embodiment is applied is not particularly limited. The resin for polyolefin-based synthetic fibers is preferred.

(Second embodiment)

Next, a second embodiment in which the polyolefin resin composition of the present invention (hereinafter also simply referred to as resin composition) is embodied will be described. In the resin composition of the present embodiment, if the content ratio of the additive of the first embodiment and the polyolefin-based resin is 100% by mass, the additive is contained at a ratio of 1 to 70% by mass and at a ratio of 30 to 99% by mass. Contains this resin.

Examples of polyolefin-based resins include high-density polyethylene, low-density polyethylene, polypropylene, and polybutene. One type of these polyolefin resins may be used alone, or two or more types may be used in combination.

The form of the resin composition of the present embodiment is not particularly limited, but it is preferably a master batch. More preferably, it is a masterbatch for polyolefin-based synthetic fibers. When manufacturing a non-woven fabric using a masterbatch, for example, when manufacturing a non-woven fabric by a spinning bonding method, the uniformity of additives in the non-woven fabric can be further improved.

(Third Embodiment)

A third embodiment in which the polyolefin-based synthetic fiber nonwoven fabric (hereinafter also referred to as synthetic fiber nonwoven fabric) of the present invention is embodied will be described. The synthetic fiber nonwoven fabric of this embodiment contains the additive of the first embodiment in a ratio of 1.0 to 7.0% by mass in the synthetic fiber nonwoven fabric.

The type of nonwoven fabric constituting the synthetic fiber nonwoven fabric of the present embodiment is not particularly limited, but examples thereof include spunbond, meltblown, composite spunbond and meltblown nonwoven fabric.

(Fourth embodiment)

Finally, a fourth embodiment in which the method for producing a polyolefin-based synthetic fiber nonwoven fabric of the present invention (hereinafter also referred to as a method for producing synthetic fiber nonwoven fabric) is embodied will be described. The manufacturing method of the synthetic fiber nonwoven fabric of this embodiment includes the steps of mixing the additive of the first embodiment with a polyolefin-based resin to obtain a resin composition, and using the obtained resin composition to spin a polyolefin-based synthetic fiber. 2. Step 3 of joining the polyolefin-based synthetic fiber into a nonwoven fabric.

In the step 1 of mixing the additive of the first embodiment with the polyolefin-based resin, it is preferable to mix the additive of the first embodiment with the polyolefin-based resin to contain the polyolefin-based synthetic fiber in a ratio of 1.0 to 7.0% by mass The additive of the first embodiment. With the above configuration, when manufacturing a non-woven fabric, for example, when manufacturing a non-woven fabric using a spinning bonding method, smoke can be reduced. In addition, the additives can be kneaded uniformly in the above steps.

The manufacturing method of the synthetic fiber constituting the synthetic fiber nonwoven fabric is not particularly limited, and a known manufacturing method can be applied. For example, melt spinning and the like can be mentioned.

According to the additive, the resin composition, the synthetic fiber nonwoven fabric, and the method for manufacturing the synthetic fiber nonwoven fabric of the above-described embodiment, the following effects can be obtained.

(1) In the above embodiment, it is used in the additive for 1 mole of carbon monohydric fatty alcohol with carbon number 16 to 32 and carbon number with monohydric fatty alcohol with carbon number 12 to 26. The proportion of oxyethylene alkyl ether was added.

Therefore, the synthetic fiber nonwoven fabric can exhibit hydrophilicity immediately after its manufacture. Furthermore, excellent absorption characteristics such as synthetic fiber non-woven fabric dot absorption and durable hydrophilicity for absorbing body fluid repeatedly and quickly can be imparted.

In addition, when manufacturing a nonwoven fabric, for example, when manufacturing a nonwoven fabric using a spin bonding method, it is possible to reduce smoking. In addition, the additives can be kneaded uniformly in the above steps.

In addition, the above-mentioned embodiment can be changed as follows.

As long as the effect of the present invention is not hindered, as a stabilizer or antistatic agent for maintaining the quality of the additive, the additive of the above embodiment can be further blended with additives usually used for adhesives, antioxidants, ultraviolet absorbers, etc. Ingredients.

Hereinafter, in order to more specifically explain the configuration and effects of the present invention, examples and the like are listed, but the present invention is not limited to these examples. In addition, in the description of the following examples and comparative examples, the part means the quality part, and the% means the mass %.

Test difference 1 (preparation of additives for polyolefin resins)

Preparation of additives for polyolefin resin (Example 1)

At 80℃, make 2.0kg of octadecyl alcohol (A-1) and 6.0kg of monooxyethylene octadecyl ether (B-1) and cis-13-docosenoic acid amide (C-1) 2.0 kg was dissolved by heating and mixed uniformly to obtain an additive for polyolefin resin.

Preparation of additives for polyolefin resins (Examples 2 to 19 and Comparative Examples 1 to 8)

The additives of Examples 2 to 19 and Comparative Examples 1 to 8 were prepared in the same order as the preparation of the additives for polyolefin resins of Example 1. Table 1 shows the types of fatty alcohols, oxyethylene alkyl ethers, and fatty acid derivatives used when formulating the additives of each example, and the content ratio (%) of each component in the additives.

Table 1

in FIG. 1

A-1: stearyl alcohol

A-2: Eicosane

A-3: Twenty-four alcohol

A-4: Cetyl alcohol

A-5: Thirty alcohol

ra-1: octanol

ra-2: tetracontyl alcohol

B-1: Monooxyethylene octadecyl ether (average addition number of ethylene oxide 1.0)

B-2: Monooxyethylene docosyl ether (average addition number of ethylene oxide 1.0)

B-3: Monooxyethylene tetracosyl ether (average addition number of ethylene oxide 1.0)

B-4: Oxyethylene octadecyl ether (average addition number of ethylene oxide 1.35)

B-5: Monooxyethylene docosyl ether (average addition number of ethylene oxide 1.35)

B-6: Monooxyethylene dodecyl ether (average addition number of ethylene oxide 1.0)

B-7: Monooxyethylene hexacosyl ether (average addition number of ethylene oxide 1.0)

B-8: oxyethylene octadecyl ether (average addition number of ethylene oxide 1.60)

B-9: Oxyethylene octadecyl ether (average addition number of ethylene oxide 1.95)

rb-1: monooxyethylene octyl ether (average addition number of ethylene oxide 1.0)

rb-2: monooxyethylene triacontyl ether (average addition number of ethylene oxide 1.0)

rb-3: oxyethylene octadecyl ether (average addition number of ethylene oxide 3.20)

rb-4: oxyethylene octadecyl ether (average addition number of ethylene oxide 2.40)

rb-5: oxyethylene octadecyl ether (average addition number of ethylene oxide 3.68)

C-1: cis-13-docosenoic acid amide

C-2: octadecyl octadecanoic acid (octadecyl octadecylate)

C-3: Sorbitol monooctadesylate (sorbitan monooctadesylate)

C-4: Glycerin monooctadecylate

rc-1: dodecyl dodecylate

rc-2: Doriacontane amide

rc-3: Polyoxyethylene (10 mol) octadecane amide (polyoxyethylene (10 mol) octadecane amide).

Test difference 2 (preparation of polyolefin-based resin composition, preparation of polyolefin-based synthetic fiber nonwoven fabric, and evaluation of manufacturability of nonwoven fabric)

Preparation of polyolefin resin composition (Examples 1 to 18 and Comparative Examples 1 to 8)

10.0 kg of additives for polyolefin resins prepared in Test Difference 1 and 10.0 kg of polypropylene resin (MFR=30) as polyolefin resins were mixed, and the mixture was added at 200°C with an extrusion molding machine By warm melting, a masterbatch as a polyolefin-based resin composition containing 50% by mass of an additive for polyolefin-based resin was obtained.

Preparation of polyolefin resin composition (Example 19)

10.0 kg of the additive for polyolefin resin to be blended in Test Difference 1 and 10.0 kg of polypropylene resin (MFR=30) were mixed to obtain a polyolefin resin composition containing 50% by mass of the additive for polyolefin resin mixture.

Preparation of Polyolefin Synthetic Fiber Nonwoven

The polyolefin resin composition containing 50% by mass of the additive for polyolefin-based resin in each example prepared as described above was 4.0% by mass (the additive for polyolefin-based resin was 2.0% by mass). (MFR=30) Mixed. Furthermore, the mixture was melt-spun at 240° C., and heat embossing roller processing was performed to prepare 20 gsm of polypropylene spun bonded nonwoven fabric (synthetic fiber nonwoven fabric). As the evaluation of the manufacturability of the synthetic fiber nonwoven fabric, the evaluation of smoke emission and the evaluation of uniformity shown below were performed. As an evaluation of the synthetic fiber nonwoven fabric itself, the hydrophilicity, point water absorption, and durable hydrophilicity immediately after the production shown below are evaluated.

In addition, in Table 1, "addition amount (%) of the additive in a nonwoven fabric" represents the blending amount (%) of the additive for polyolefin resin in a synthetic fiber nonwoven fabric. In addition, the addition mole number of ethylene oxide of oxyethylene alkyl ether was calculated on the 7890B GC system manufactured by Agilent using the DB-1 122-1032 column manufactured by Agilent.

Evaluation of smoking

Based on the following evaluation criteria, it was judged whether or not there was smoke when manufacturing the spunbonded nonwoven fabric.

Evaluation criteria for smoking

◎ (Excellent): Although a little smoke was seen, it was extremely small and few.

○ (Good): Although there is smoke, it is rare.

× (bad): There is much smoke, and it is difficult to spin.

Evaluation of uniformity

Based on the evaluation criteria described below, it was determined whether or not additives for polyolefin-based resins were uniformly added during the production of the spunbonded nonwoven fabric.

Evaluation criteria of uniformity

◎ (Excellent): No fiber breakage was observed during spinning, and the thickness of the fiber was uniform and the additives were added uniformly.

○ (good): Although no fiber breakage was observed during spinning, the additives were not uniformly mixed, so the thickness of the fiber was not uniform.

× (Bad): Since additives are not added uniformly, fiber breakage frequently occurs.

Test difference 3 (evaluation of polyolefin-based synthetic fiber nonwoven fabric)

Evaluation of Polyolefin Synthetic Fiber Nonwoven

The nonwoven fabric was evaluated using the aforementioned spun bonded nonwoven fabric. As an evaluation item of the nonwoven fabric, the hydrophilicity, spot water absorption, and durable hydrophilicity evaluation immediately after the production were performed.

Evaluation of hydrophilicity immediately after manufacturing

Immediately after the preparation of the aforementioned spunbonded nonwoven fabric, the spunbonded nonwoven fabric was placed on a horizontal plate, and 0.4 ml of 0.9% physiological saline was dripped from a height of 10 mm using a burette, and the dripped physiological saline was measured to be completely absorbed The time required until the penetration of water, that is, the time required for water penetration, was evaluated for the hydrophilicity immediately after the production according to the following evaluation criteria.

Evaluation criteria of hydrophilicity immediately after manufacturing

◎ (Excellent): The time required for water penetration is less than 1 second.

○ (Good): The time required for water penetration is 1 second or more and less than 3 seconds.

× (Bad): The time required for water penetration is 3 seconds or more.

Evaluation of point water absorption

The aforementioned spunbonded nonwoven fabric was subjected to humidity adjustment at 20°C in a thermostatic chamber at 60%RH for 24 hours. After that, it was placed on a horizontal plate, and 0.05 ml of water droplets dyed blue was dropped from a height of 10 mm using a syringe and absorbed. After that, the length of the fiber direction and the direction perpendicular to the fiber was measured for the dripping marks, and the water absorption at the point was evaluated according to the following evaluation criteria.

Evaluation criteria for point water absorption

◎(Excellent): The length of the fiber direction and the fiber vertical direction are less than 10mm.

○ (Good): The length of the fiber direction and the fiber vertical direction are both 10 mm or more and less than 20 mm.

× (Poor): The length of either the fiber direction or the fiber vertical direction is 20 mm or more.

Evaluation of durable hydrophilicity

The spunbonded nonwoven fabric prepared above was cut into small pieces of 10 cm×10 cm, and the humidity was adjusted at 20° C. in a constant temperature room of 60% RH for 24 hours. After that, place a humidity-adjusted nonwoven fabric on the five pieces of filter paper, and then stand upright in the center of the upper part of the cylinder with an open inner diameter of 1cm at both ends. Inject 5ml of 0.9% physiological saline into the cylinder. The time required for the injected saline solution to be completely absorbed by the nonwoven fabric. After that, the nonwoven fabric was taken out and air-dried at 40°C for 90 minutes, thereby repeating the above procedure again, thereby measuring the time required for the physiological saline in total three times to be completely absorbed by the nonwoven fabric. Based on the time measured in the third time, the durable hydrophilicity was evaluated according to the following evaluation criteria.

Evaluation criteria for durable hydrophilicity

◎ (Excellent): The time required for the physiological saline solution to be absorbed is less than 3 seconds.

○ (Good): The time required until physiological saline is absorbed is 3 seconds or more and less than 5 seconds.

× (Poor): The time required for physiological saline to be absorbed is 5 seconds or more.

As is clear from the results in Table 1, according to the present invention, it is possible to knead the additive uniformly with little smoke when manufacturing a nonwoven fabric. In addition, especially the synthetic fiber non-woven fabric can exhibit hydrophilicity immediately after its manufacture. Furthermore, it has the effect of imparting good water absorption and durable hydrophilicity to the synthetic fiber nonwoven fabric.

Claims (12)

An additive for polyolefin-based resins, characterized by containing the following fatty alcohols and the following oxyethylene alkyl ethers, fatty alcohols: monovalent fatty alcohols having carbon numbers of 16 to 32, and oxyethylene alkyl ethers: for 1 mole A monovalent fatty alcohol with a carbon number of 12 to 26 is a compound in which ethylene oxide is added at an average ratio of less than 2 moles. The additive for polyolefin resin according to claim 1, wherein the fatty alcohol is a monovalent fatty alcohol having 18 to 26 carbon atoms. The additive for polyolefin resin as claimed in claim 1 or 2, wherein the oxyethylene alkyl ether is a monovalent fatty alcohol with a carbon number of 16 to 24 for 1 mol, and the ethylene oxide is less than 2 mol on average Compounds added in proportion. The additive for polyolefin-based resin according to claim 1 or 2, wherein the oxyethylene alkyl ether is added to ethylene oxide at an average ratio of not more than 1.5 mol for 1 mol of the monobasic fatty alcohol Compound. The additive for polyolefin resin according to claim 1 or 2, wherein if the total content ratio of the fatty alcohol and the oxyethylene alkyl ether is 100% by mass, the fatty alcohol is contained at a ratio of 1 to 70% by mass And containing the oxyethylene alkyl ether in a ratio of 30 to 99% by mass. The additive for polyolefin-based resin according to claim 1 or 2, which further contains the following fatty acid derivative, fatty acid derivative: an ester compound selected from a monocarboxylic acid having 16 to 24 carbon atoms and a monovalent fatty alcohol, and having 16 to 16 carbon atoms 24. At least one compound of an ester compound of a monocarboxylic acid and a polyhydric fatty alcohol and a fatty amine having 16 to 24 carbon atoms. The additive for polyolefin-based resin according to claim 6, wherein if the content ratio of the fatty alcohol, the oxyethylene alkyl ether and the fatty acid derivative is 100% by mass, the content is contained at a ratio of 10 to 40% by mass The fatty alcohol contains the oxyethylene alkyl ether at a ratio of 30 to 80% by mass, and the fatty acid derivative at a ratio of 1 to 45% by mass. The additive for polyolefin-based resins according to claim 1 or 2, wherein the polyolefin-based resin is a resin for polyolefin-based synthetic fibers. A polyolefin-based resin composition characterized in that if the content ratio of the additive for polyolefin-based resin and the polyolefin-based resin according to any one of claims 1 to 8 is 100% by mass, it is 1 to 70% by mass It contains the additive for polyolefin resin and the polyolefin resin in the ratio of 30 to 99% by mass. A polyolefin-based synthetic fiber nonwoven fabric, characterized in that the polyolefin-based synthetic fiber contains the additive for polyolefin-based resin according to any one of claims 1 to 8 in a ratio of 1.0 to 7.0% by mass. A method for manufacturing a polyolefin-based synthetic fiber nonwoven fabric, characterized by comprising: the step 1 of obtaining the resin composition by mixing the additive for polyolefin-based resin according to any one of claims 1 to 8 with a polyolefin-based resin; The resin composition of is subjected to a step 2 of spinning a polyolefin-based synthetic fiber, and a step 3 of joining the polyolefin-based synthetic fiber into a nonwoven fabric. The method for producing a polyolefin-based synthetic fiber nonwoven fabric according to claim 11, wherein in the step 1, the additive for the polyolefin-based resin and the polyolefin-based resin are mixed into the polyolefin-based synthetic fiber at 1.0 to The ratio of 7.0% by mass contains the additive for polyolefin resin.