KR20110076301A - High-softness polyolefin staple fiber and method for fabricating the same and thermal bonding non-woven using thereof - Google Patents

Abstract

PURPOSE: A polyolefin-group simple fiber, a manufacturing method thereof and a thermal bond non-woven fabric using the same are provided to offer high ductility and little skin irritations. The polyolefin-group simple fiber has high ductility and lowering stimulation, and the simple fiber and the non-woven fabric hold excellent property of the matters. CONSTITUTION: The method of manufacturing the polyolefin-group simple fiber has following processes. A polymer is copolymerized to propylene 74~82 weight%, ethylene 12~18 weight%, butene 6~8 weight%. A melting material is spun at a spinning temperature of 220~270°C at a speed of 50 - 140 m / min. A stretching ratio of the emitted unstretched yarn is 1.5 - 4.0 and a preheating temperature is 50 ~ 80°C. A crimping gives crimp to the stretched filament. In a surface process, a spin finish is sprayed and fixed on the filament in which the crimp is given. A mono-filament cuts in advance the surface-treated filaments up to a fixed length after heat-setting the surface processed filament.

Description

High-softness polyolefin staple fiber and method for fabricating the same and thermal bonding non-woven using according to the present invention.

The present invention relates to a copolymer of polyolefin short fibers and a polymer copolymerized by the method for producing the same, a method for preparing polyolefin short fibers having high heat fusion property of hypoallergenic, high ductility, and a nonwoven fabric using the same.

In general, polyolefin-based short fibers of polyethylene, polypropylene, and copolymers thereof are widely used as a nonwoven material due to their unique low melting point and excellent chemical resistance.

These non-woven fabrics are fabrics made by adhering or tangling fiber aggregates by mechanical or chemical treatment such as mechanical manipulation or heat bonding without weaving, weaving, or knitting. They are felt, resin-bonded nonwoven fabric, needle punch, spun bond, spun lace, Emboss films, wet nonwovens, and the like fall into this category. By narrowing, it means that the contact of the web (web) overlapped with the random (random) and the fiber is bonded by resin and used as a wick. Also called adhesive fabrics and bonded fabrics. Such a nonwoven fabric can be produced by various methods, such as needle punching method, chemical bonding method, thermal bonding method, melt blown method, spunlace method, stitch bond method, spunbond method is known.

Nonwoven fabric made of polyolefin-based short fibers is used for hygiene products such as napkins and diapers because the touch is soft and high strength. In particular, polypropylene short fibers are processed into thermal-bonded nonwoven fabrics through calender bonding or air-through bonding due to their unique low melting point and excellent chemical resistance.They are disposable disposable diapers for adults, disposable diapers for adults, feminine hygiene products, hygienic nonwoven fabrics, and medical grades. It is used as a cover material for nonwoven fabrics and towels, masks, filter bags for vacuum cleaners, and table cover fabrics. Therefore, there is a lot of contact with the skin is required for the flexibility to improve the hypoallergenic and feel to the skin.

In order to give soft touch and high tensile strength to the nonwoven fabric, polypropylene heat-adhesive nonwoven fabric of Japanese Patent Application Laid-Open No. 2002-235237 pursues softness and high tensile strength through fine fineness by injecting salicylic acid metal salt as a masterbatch pellet as a crystallization inhibitor. However, the experiment on the spunbond nonwoven fabric is different from the manufacturing method of the thermal bond nonwoven fabric through short fibers. Spunbonded nonwoven fabrics exhibit higher tensile strength than short fiber thermalbonded nonwoven fabrics, but soft touch is typically poor. In addition, according to the present technology, when the ethylene content is 1.5 wt% or more with respect to the spunbond nonwoven fabric made from the propylene / ethylene random copolymer, the crystallinity may be low and may cause a decrease in strength of the nonwoven fabric.

Therefore, there is a need for development of excellent softness and high softness of short fibers and non-woven fabrics for hygiene products such as infant diapers, surface materials of women's products, and wet wipes, which have a soft touch to prevent and alleviate skin irritation such as inflammation. .

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a polyolefin short fiber and a method of manufacturing the same and a thermal bond nonwoven fabric having low ductility and low skin irritation.

In addition, the present invention provides a high-ductility polyolefin short fibers having a high ductility and hypoallergenic properties and excellent properties of short fibers and non-woven fabrics and a method of manufacturing the same and a thermal bond nonwoven fabric using the same.

In order to achieve the above object, the present invention provides a method for producing polyolefin short fibers, comprising: melting a polymer copolymerized with 74 to 82% by weight of propylene, 12 to 18% by weight of ethylene, and 6 to 8% by weight of butene; Spinning the melt at a rate of 50 to 140 m / min at a spinning temperature of 220 to 270 ° C .; Stretching the spun untwisted yarn at a draw ratio of 1.5 to 4.0 and a preheating temperature of 50 to 80 ° C; Crimping to impart crimp to the stretched filaments; A surface treatment step of spraying and fixing the spinning oil onto the crimped filament; And a short fiber forming step of cutting the surface-treated filament and cutting it by a predetermined length after heat setting.

Further, the copolymerized polymer has a melt index (MI) of 10 to 30 g / 10 min, an isotactic index of 80 or more, and a melting point (DSC) of 135 to 150 ° C. To provide.

In addition, the melt provides a method for producing a high ductility polyolefin short fiber, characterized in that the additive further comprises at least one additive selected from the group consisting of antioxidants, UV stabilizers, process stabilizers, colorants.

In addition, the additives provide a method for producing a high ductility polyolefin short fiber, characterized in that 0.1 to 3% by weight in the melt.

In addition, in the polyolefin short fibers, a high ductility polyolefin short fiber is provided, which is made of a polymer copolymerized with 12 to 18% by weight of ethylene, 6 to 8% by weight of butene, and 74 to 82% by weight of propylene.

In addition, the copolymerized polymer is a high ductility polyolefin, characterized in that the melt index (MI) is made of homopolypropylene having a melt index (MI) of 10 to 30g / 10min, an isotactic index of 95 or more and a melting point (DSC) of 160 to 165 ℃ Provides staple fibers.

In addition, there is provided a high-ductility polyolefin-based short fibers, which are produced by the above method.

In addition, by using the functional polyolefin-based short fibers or the above-described short fibers produced by the above method, there is provided a high-ductility polyolefin-based nonwoven fabric characterized in that produced by the thermal bonding method.

In addition, the thermal bonding method provides a highly flexible polyolefin-based nonwoven fabric characterized in that the calendar bonding method or the air-through bonding method.

In addition, the calender bonding method is characterized in that the heat-adhesion between the fibers are produced by carding the short fibers at a speed of 80 to 150 mpm, and then making a nonwoven web while passing the web between the hot rolls set to 140 to 165 ℃ It provides a highly flexible polyolefin nonwoven fabric.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, it should be noted that in the drawings, the same components or parts denote the same reference numerals as much as possible. In describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order not to obscure the subject matter of the present invention.

As used herein, the terms "about", "substantially", and the like, are used at, or in close proximity to, numerical values as are indicative of preparation and material tolerances inherent in the meanings mentioned, and are intended to be accurate or to facilitate understanding of the invention. Absolute figures are used to prevent unfair use by unscrupulous infringers.

As used herein, the term "nonwoven fabric" refers to a fabric, felt, and fibrous web made by bonding or tangling fiber aggregates by mechanical or chemical treatment such as mechanical manipulation or heat bonding without undergoing weaving, weaving, or knitting. use.

Figure 1 shows a process for producing a polyolefin-based short fibers according to an embodiment of the present invention.

The present invention relates to a non-woven polyolefin short fiber for copolymerization of propylene, ethylene, butene and having no skin irritation and having a high softness function.

Polyolefin-based short fibers according to a preferred embodiment of the present invention is a spinning step of producing a non-drawn yarn by spinning the melt through a melting step of propylene, ethylene, butene copolymerized polymer melt as shown in FIG. The spinning non-stretched yarn is passed through a crimping step of imparting crimp to the stretched filament. The filament is formed into a short fiber forming step of cutting a predetermined length into a short fiber through a surface treatment step of spraying, fixing and heat-setting the spinning oil onto the fiber.

The raw material of the fiber according to the present invention is produced by mixing and copolymerizing propylene, ethylene and butene randomly copolymerized with 74-82% by weight of propylene, 12-18% by weight of ethylene and 6-8% by weight of butene.

If the mixing ratio is out of the above radioactivity may be reduced or the flexibility after manufacturing short fibers.

The copolymerized polymer preferably has a melt index (MI) of 10 to 30 g / 10 min, an isotactic index of 80 or more, and a melting point (DSC) of 135 to 150 ° C.

The short polypropylene fiber made of the copolymerized polymer has a unique low melting point and excellent chemical resistance and is suitable as a surface material of hygiene products such as diapers and sanitary napkins due to its high ductility and hypoallergenicity.

When the copolymerized polymer is prepared from short fibers, the copolymerized polymer is melted, and then spun at a spinning speed of about 50 to 140 m / min at a spinning temperature of 220 to 270 ° C to be appropriately controlled and drawn between draw ratios of 1.5 to 4.0. After stretching to a temperature of 50-80 ° C., crimping is given, and the spinning oil is sprayed to attach the spinning oil to the fiber surface.

The melted melt of the copolymerized polymer may optionally further include at least one additive selected from the group consisting of antioxidants, UV stabilizers, process stabilizers, and colorants including white pigments, and the content of such additives is total polypropylene. If it exceeds 3.0 wt% with respect to the short fiber weight, it is preferable to include less than 3.0 wt% because the physical properties of the short fiber are impaired, and if it is contained less than 0.1 wt%, the effect of the additive cannot be expected. Would be desirable. Therefore, it is preferable that the additive contains 0.1 to 3.0% by weight of the polyolefin based short fibers in the short fibers.

After heat setting at about 100 to 120 ° C. for about 8 to 12 minutes, the fiber is cut to have a length of about 30 to 50 mm, and the final fiber fineness is 2.0 to 4.0 denier, and the average elongation is 300 to 400% polyolefin. Fibers can be produced.

The spinning oil may be machine oil, liquid paraffin, white oil, etc. as mineral oil and synthetic oil-based lubricant as an oil to smooth the fiber manufacturing process.

Alternatively, a heat resistant spinning oil may be used to increase the heat resistance of the short polyolefin fibers. The heat-resistant spinning oil may use a double di-quaternary polydimethylsiloxane hydrophilic lubricant, it will be preferable to further include an antistatic agent.

In case of using the double quaternary polydimethylsiloxane hydrophilic lubricant and the antistatic agent, 95 to 99% by weight of the double quaternary polydimethylsiloxane hydrophilic lubricant and 1 to 5% by weight of the antistatic agent are used as heat-resistant spinning oil. It is preferable.

Alternatively, in order to increase the antimicrobial activity of short polyolefin fibers, a functional spinning oil containing a mixture of the spinning oil and a phytoncide may be used.

The phytoncide is a fragrant substance that the tree emits in order to protect itself from various pests and bacteria, and itself contains bactericidal and insecticidal components. The main component of phytoncide is an organic compound of Terpene family. These terpenes are known to have antibacterial, sedative, deodorant, stress relief and the like.

In addition, phytoncide, a natural substance, is known to be most effective in preventing allergy without causing side dust mite repelling effect to nearly 90%.

The mixing ratio of the spinning oil and phytoncide may be prepared by mixing 50 to 99% by weight of the spinning oil and 1 to 50% by weight of the phytoncide.

It will be desirable for the spinning emulsion described above to be applied to short fibers in an amount of 0.1 to 10% by weight of the polyolefin based short fibers.

When a short fiber is produced by the method according to a preferred embodiment of the present invention, a thermal bond process for manufacturing a nonwoven fabric may be performed. The thermal bonding method may be performed using a calendar bonding method and an air through bonding method. Calender bonding method is to produce a non-woven web after carding short fibers at a speed of 80 to 150 mpm, and the heat-adhesion between the fibers is produced as the web passes between hot rolls set to about 140 ~ 165 ℃ Can be. In this case, the basis weight of the nonwoven fabric is preferably 20 to 40 gsm.

On the other hand, if foreign matters are attached to the surface of the fiber, bubbles are generated at the time of fixation, which may cause deterioration of the properties of the nonwoven fabric.

In the present invention, in manufacturing a thermal bond nonwoven fabric through a calender bonding facility, the hot roll temperature of hot roll is most suitable for the nonwoven fabric production rate, the shape of the embossed pattern of the roll, the difference between the roll setting temperature and the surface temperature, and the like. It is not an absolute result but a relative result because it may vary depending on the production equipment conditions of the calender bonding method and the fineness of the short fibers used as raw materials.

The high ductility polyolefin short fibers according to the present invention are produced by copolymerizing propylene, ethylene and butene, and have excellent physical properties than conventional polyolefin short fibers and nonwoven fabrics.

In addition, the highly flexible polyolefin nonwoven fabric of the present invention, unlike the thermal bond nonwoven fabric composed of short fibers made of only homopolypropylene, which is widely used as a hygiene material, due to the very soft properties that conventional polyolefin short fibers do not have, skin irritation such as severe It has a preventive and mitigating effect.

Therefore, the high ductility polyolefin short fibers and the nonwoven fabric of the present invention are not only suitable for hygiene products such as diapers, sanitary products, wet tissues, etc., but also have a skin irritation prevention and relieving effect, and thus can be applied to more functional hygiene products.

1. Preparation of Polyolefin Short Fibers

Example 1

82 wt% of propylene, 12 wt% of ethylene, and 6 wt% of butene were mixed to prepare the unstretched yarn at a spinning temperature of 230 ° C. and a spinning speed of 50 to 100 m / min.

The draw ratio of the unstretched yarn is properly adjusted between 1.5 and 4.0, stretched at a preheating temperature of 70 ° C. to impart crimping in the crimper, and the spinning oil is sprayed to contain 0.6 wt% of the spinning oil with respect to the total short fiber weight. The spinning oil is fixed to the surface of the fiber, heat-fixed at a temperature of 100 to 110 ° C. for about 10 minutes, and the fiber is cut to 40 mm in length to give a final fiber fineness of 1.5 to 3.0 denier and an average elongation of 300 to 380% polyolefin. Short fibers were prepared.

Example 2

Work was carried out in the same manner as in Example 1, but a polyolefin short fiber was prepared by mixing 80% by weight of propylene, 13% by weight of ethylene, and 7% by weight of butene in the copolymerized polymer.

Example 3

Work was carried out in the same manner as in Example 1, but the polyolefin short fibers were prepared by mixing 74 wt% propylene, 18 wt% ethylene, and 8 wt% butene in the copolymerized polymer.

Comparative Example 1

The operation was carried out in the same manner as in Example 1, except that homopolypropylene was used instead of the copolymerized polymer to prepare polyolefin short fibers.

2. Preparation of Polyolefin Thermal Bonding Nonwoven Fabric

Each non-woven web of polyolefin short fibers obtained by the above method was carded at a speed of 115 mpm, and passed through two hot rolls to prepare a calender-bonded nonwoven fabric having a basis weight of 22 g / m 2.

At this time, while the temperature of the hot roll to 130 ~ 150 ℃ to find the hot-opening temperature (hereinafter referred to as the optimum hot roll temperature) of the most excellent temperature of the nonwoven fabric tensile strength was measured and measured the physical properties.

* Method of Analysis

1. Melt Index (MI): According to ASTM D 1238

* Homopolypropylene and random copolymer series: 230 ℃, 2.16kg load

* PE series such as HDPE, LDPE: 190 ℃, 2.16kg load

2. Isotactic Index (I.I): ISO 9113: 1986... Plastics-Polypropylene (PP) and propylene-copolymer thermoplastics-Determination of isotactic index: After boiling normal heptane to melt the atactic component, the remaining isotactic component is weighed and expressed as wt%, and the weight percent isotactic index It is called.

3.Xylene Soluble (hereinafter referred to as XS): ISO 16152: 2005

4. Radioactivity: Evaluated by measuring the number of fiber breaks and the number of spin drops occurring under the detention of 37,125 holes.

Only one round or drop is less than one time: ◎

However, trimming or dropping is 1 ~ 3 times / time: ○

Only three times / time of drop or drop: △

No radiation: ×

5. Elongation: Evaluated by the number of trimming in the softening process

Less than 1 time / hour: ○, 1 ~ 2 times / time: △, More than 3 times / hour: ×

6. Crimping workability: The number of times that the tow that has been visually observed and drawn fails while passing through the crimper.

Less than 1 time / hour: ○, 1 ~ 2 times / time: △, More than 3 times / hour: ×

7. Single fiber fineness: Determination of fineness based on ASTM D1577

8. Non-woven carding property: When short fiber passes through the carding machine, curling or flying phenomenon occurs between card rolls, or it is judged as bad when the web formation is not good.

9. Basis weight: weight of nonwoven fabric (g / ㎡)

10. Nonwoven fabric tensile strength and elongation: cut-strip method of JIS L 1096 (sample width 5cm, length 14cm)

MD: Machine direction of nonwoven fabric / CD: Transverse direction of nonwoven fabric

11.TBI (Thermal Bondability Index) = √ {(MD Strength × CD Strength)} × (20 / Basic Weight)

division weight Strength (kg / 5cm) Elongation (%) (g / ㎡) MD CD MD CD Example 1 22.0 4.75 1.31 52 96 Example 2 22.0 4.73 1.35 56 94 Example 3 22.0 4.76 1.34 53 97 Comparative example 22.0 4.10 0.95 38 63

Table 1 is an evaluation of the properties of the nonwoven fabrics prepared from the examples and comparative examples, the nonwoven fabric made of high-ductility polyolefin-based short fibers according to the present invention strength and elongation than the nonwoven fabric made of homo polypropylene (homo polypropylene) You can see that is excellent.

◎ Skin irritation evaluation test method

To evaluate the skin irritation of nonwoven fabrics, a patch test was conducted on 25 healthy men and women.

In order to determine the degree of skin irritation of the non-woven fabric thermally bonded to the polyolefin short fibers of the Examples and Comparative Examples prepared above, it was compared with the cosmetics generally used for skin protection. The nonwoven fabric was attached to the test subject's skin for 24 hours, the skin condition change after 2 hours after the nonwoven fabric was removed, and a certain amount (approximately 0.2 g) of the cosmetic sample was added to the pin chamber, and the sample's skin was minimized while minimizing the loss of the sample. After 24 hours of attachment, the pin chamber was removed and the skin condition change after 2 hours was evaluated by two experts to evaluate the degree of irritation and stimulation according to the criteria shown in Table 2, and the results are shown in Table 3. Shown in

Irritation degree Irritation Criteria 0 - No symptoms One + Have only slight erythema reactions 2 + Clear erythema edema but no blisters 3 ++ Clear erythema, edema, blisters 4 +++ If you have a cannon

division Judgment result (the number of people) Skin irritation index ++ + + － Example 1 0 0 0 25 0.00 Example 2 0 0 One 23 0.04 Example 3 0 0 One 24 0.04 Comparative example 0 0 3 23 0.13 Cosmetic A 0 0 3 24 0.13 Cosmetic B 0 0 2 23 0.09 Cosmetic A is a skin lotion for men and Cosmetic B is a skin lotion for women.
Skin irritation index = irritability × number of subjects responding / total number of subjects

As shown in Table 3, the comparative example was evaluated with the same irritation index as cosmetics A, and the skin irritation index of Example 1 was 0.00, which is the lowest value than other examples and comparative examples and cosmetics A and B. have. In addition, it can be seen from Table 3 that Examples 2 and 3 also have lower skin irritation indices than Comparative Examples, cosmetics A and B. It can be seen that the nonwoven fabric made of the highly flexible polyolefin short fibers of the present invention has almost no skin irritation. Can be.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. It will be clear to those who have knowledge of.

1 is a flow chart of the manufacturing process of the polyolefin-based short fibers according to an embodiment of the present invention.

Claims (10)

In the method for producing a polyolefin short fiber, Melting a polymer copolymerized with 74 to 82% by weight of propylene, 12 to 18% by weight of ethylene, and 6 to 8% by weight of butene; Spinning the melt at a rate of 50 to 140 m / min at a spinning temperature of 220 to 270 ° C .; Stretching the spun untwisted yarn at a draw ratio of 1.5 to 4.0 and a preheating temperature of 50 to 80 ° C; Crimping to impart crimp to the stretched filaments; A surface treatment step of spraying and fixing the spinning oil onto the crimped filament; And And a short fiber forming step of cutting the surface-treated filaments by a predetermined length after heat setting. The method of claim 1, The copolymerized polymer has a melt index (MI) of 10 to 30g / 10min, an isotactic index of 80 or more, and a melting point (DSC) of 135 to 150 ° C. The method of claim 1, Method for producing a high ductility polyolefin-based short fibers, characterized in that the melt further comprises at least one additive selected from the group consisting of antioxidants, UV stabilizers, process stabilizers, colorants. The method of claim 3, The additive is a method for producing a high ductility polyolefin-based short fibers, characterized in that 0.1 to 3% by weight in the melt. In the polyolefin short fiber, A high ductility polyolefin short fiber, which is made of a polymer copolymerized with 12 to 18% by weight of ethylene, 6 to 8% by weight of butene and 74 to 82% by weight of propylene. The method of claim 5, The copolymerized polymer is made of homopolypropylene having a melt index (MI) of 10 to 30 g / 10 min, an isotactic index of 95 or more and a melting point (DSC) of 160 to 165 ° C. fiber. High-ductility polyolefin type short fiber manufactured by the method of any one of Claims 1-4. A functional polyolefin-based short fiber produced by the method of any one of claims 1 to 6 or a short fiber of any one of claims 5 and 6, characterized in that it is produced by the thermal bonding method Soft polyolefin-based nonwovens. The method of claim 8, The thermal bonding method is a highly flexible polyolefin-based nonwoven fabric, characterized in that the calendar bonding method or air-through bonding method. 10. The method of claim 9, The calender bonding method is characterized in that the heat-adhesion between the fibers are produced by carding short fibers at a speed of 80 to 150 mpm, and then making a nonwoven web while passing the web between hot rolls set at 140 to 165 ℃. Highly ductile polyolefin-based nonwovens.

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