JP2013204180A - Core-sheath conjugate monofilament for artificial hair - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a monofilament for artificial hair superior in combing properties and durability.SOLUTION: The core-sheath conjugate monofilament for artificial hair is a monofilament having a core-sheath conjugate structure which has a core part made of a polyamide-based resin layer and a fluorine resin layer in its sheath part. A ratio of a cross section of the core part to the sheath part is in a range of 60:40-90:10. The fluorine resin layer in the sheath part has such an effect as to lower friction, and accordingly the core-sheath conjugate monofilament for the artificial hair obtains considerably improved combing properties, and simultaneously has properties superior in bending durability.

Description

  The present invention relates to a core-sheath composite monofilament for artificial hair, which exhibits excellent slipperiness due to the fluororesin layer in the sheath, has good combing properties, and has excellent bending durability.

  Examples of forms in which artificial hair is used include wigs that are worn on the entire head, and artificial hair that is partially accentuated. Typical materials for the hair material include acrylic resin, vinyl chloride resin, polyester resin, polyamide resin and the like. When partially used on the head to cover thin hair, it is required to have a quality close to that of human hair, and polyester and polyamide resin artificial hair that is unlikely to feel uncomfortable with its own hair is preferred. .

  On the other hand, acrylic and vinyl chloride resin products with excellent color developability are frequently used for purchasers who prefer blondes and silver hair, which are often found in Western countries, as well as fancy colors such as red, blue, and fluorescent colors that emphasize fashion. Yes.

  When manufacturing wigs, the product that uses 100% human hair is the best in terms of quality. However, in China, the main production area of human hair, the number of people who stretch their hair for a long time has decreased due to changes in the living environment, and the price of human hair has been rising year by year. As a result, the manufacture of wigs is forced to use human hair mixed with relatively inexpensive artificial hair for the purpose of cost reduction.

  In order to produce a good product that is not inferior to 100% human hair, artificial hair that has characteristics similar to human hair that do not feel strange even when mixed with human hair is preferable. Furthermore, by increasing the mixing rate of artificial hair, the amount of expensive human hair used can be reduced, and the cost can be reduced.

  Artificial hair made of polyamide resin is soft and can feel good, but it is inferior in bending durability compared to human hair. Furthermore, in the case of polyamide 6, the dimensional change due to moisture absorption is large and very difficult to handle. is there.

  In order to cover such drawbacks, for example, artificial hair using a semi-aromatic polyamide resin having excellent heat resistance for the sheath layer as a core-sheath composite structure (for example, see Patent Document 1) has been proposed. Although artificial hair has improved heat resistance, which is a weak point of polyamide resin, there is a concern that peeling of the sheath layer and curling may occur due to changes in the usage environment due to the difference in moisture absorption characteristics of the core-sheath layer.

  In addition, artificial hair with emphasis on softening (for example, see Patent Document 2) in which a polyamide resin that is softer than the core layer is used for the sheath layer has been proposed, but with this artificial hair, a texture close to human hair can be obtained. However, the durability against friction and bending repeatedly applied at the time of combing and shampooing is insufficient, and it is not preferable because it becomes artificial hair with a short usable period.

  On the other hand, many artificial hair made of polyester resin with excellent heat resistance has also been proposed, but it has poor curl setting properties due to its rigid resin characteristics, and since it has almost no moisturizing properties, it is easy to generate static electricity, and entanglement and dirt adhere to it. In addition to many drawbacks such as being easy to handle, when it is used as artificial hair, it requires a processing step for imparting various functions, and if high functionality is required, it becomes a very expensive product.

  Artificial hair using a polyamide resin has an excellent texture, but has a problem in durability, and a product that can be used stably for a long period of time is required.

JP 2008-69505 A JP 2007-291541 A

  The present invention has been achieved as a result of examining the solution of the problems in the above-described prior art as an object.

  Accordingly, an object of the present invention is to provide a core-sheath composite monofilament for artificial hair that has both good combability and durability that have never been achieved.

  In order to achieve the above object, according to the present invention, a monofilament having a core-sheath composite structure in which a core part is made of a polyamide-based resin layer and a sheath part has a fluororesin layer, and the cross-sectional area of the core part and the sheath part is A core-sheath composite monofilament for artificial hair is provided, wherein the ratio is in the range of 60:40 to 90:10.

  In addition, in the core-sheath composite monofilament for artificial hair of the invention, the fluororesin forming the fluororesin layer is a modified ethylenetetrafluoroethylene copolymer resin having a reactive group, and according to JIS P-8115. In the measured bending fatigue test, it is preferable that the number of reciprocal bending before cutting is 5000 or more, and any of these conditions is preferable, and when these conditions are applied, further excellent effects can be expected.

  According to the present invention, as described below, a core-sheath composite monofilament for artificial hair can be obtained which exhibits good slipperiness due to the fluororesin of the sheath part, has good combing properties, and has excellent bending durability.

  Hereinafter, the present invention will be specifically described.

  Since the core-sheath composite monofilament for artificial hair according to the present invention achieves low friction on the surface of the artificial hair and protection of the polyamide-based resin in the core by the fluororesin layer disposed on the sheath of the monofilament in the core-sheath composite form, It has achieved high dimensionality and bending durability at a high level.

  In the core / sheath composite monofilament for artificial hair of the present invention, the core is required to have a polyamide resin layer, and the sheath must have a fluororesin layer.

  Specific examples of the polyamide resin constituting the core include polyamide 6 (hereinafter referred to as N6), polyamide 66 (hereinafter referred to as N66), polyamide 6/10 (hereinafter referred to as N610), polyamide 6/12. (Hereinafter referred to as N612), polyamide 11 (hereinafter referred to as N11), polyamide 12 (hereinafter referred to as N12), and the like. Among these, N6 or N610 is preferably used.

Specific examples of the fluororesin include tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (hereinafter referred to as PFA), tetrafluoroethylene copolymer (hereinafter referred to as PFA).
ETFE), tetrafluoroethylene / hexafluoropropylene copolymer (hereinafter referred to as FEP), etc. Among them, modified ethylenetetrafluoroethylene copolymer resin having a reactive group, modified ETFE or modified EFEP preferable. Furthermore, the modified ethylenetetrafluoroethylene copolymer resin having the reactive group is most preferably an ethylene perfluoroethylenepropene copolymer resin (hereinafter referred to as EFEP).

  The cross-sectional area ratio of the core part to the sheath part of the core / sheath composite monofilament constituting the core / sheath composite monofilament for artificial hair of the present invention needs to be 60:40 to 90:10, preferably 70:30 to It is in the range of 80:20.

  Here, when the cross-sectional area ratio of the core portion and the sheath portion is out of the above range, for example, when the cross-sectional area ratio of the sheath portion is low, the EFEP resin layer becomes too thin and the bending durability is lowered and the monofilament is cut. It becomes easy to do. In addition, the sheath part is easily cracked, and the good sliding due to the low friction effect of the EFEP resin is not exhibited.

  On the contrary, when the cross-sectional area ratio of the EFEP resin layer in the sheath portion is increased, characteristics such as flexibility and moisture retention property of the polyamide-based resin are lost. Furthermore, when there are many EFEP resin layers with high specific gravity, the monofilament will become heavy and the feeling of wearing a wig will worsen.

  Furthermore, in the core-sheath composite monofilament for artificial hair of the present invention, it is preferable that the number of reciprocal bending until cutting is 5000 or more in a bending fatigue test measured according to JIS P-8115.

  When the number of bendings until cutting is less than the above range, the durability against repeated bending in washing hair or turning over at bedtime is insufficient, which is not preferable because the product life is shortened.

  Moreover, although the core-sheath composite monofilament for artificial hair of the present invention is premised on being colored with about 30 variations from the intended use, a plurality of coloring methods can be proposed. The transparency of the sheath is extremely high, so even if only the polyamide-based resin in the core is colored, the color development is good, and a strong gloss can be obtained due to the optical characteristics of the EFEP resin layer in the sheath. It is possible to obtain artificial hair with a bright color that is similar to a resin. As a coloring method, color pellets colored with a polyamide-based resin as a base are mixed and colored in accordance with a target color density.

  Next, when only the sheath EFEP resin layer is colored, artificial hair with a three-dimensional effect can be obtained by passing light through the polyamide-based resin in the core. As the coloring method, the method using the color pellets described above and the dyeing method can be applied.

  Furthermore, when both the core part and the sheath part are colored, a product having the same hue as that of the conventional polyamide resin artificial hair can be realized. As a coloring method, a method of dyeing only the sheath EFEP layer can also be selected, but it is preferable that both the core and the sheath are colored using color pellets in order to simplify the manufacturing process.

  The core-sheath composite monofilament for artificial hair of the present invention is a continuous yarn composed of one single yarn, and may have any cross-sectional shape such as a circle, a triangle, a square, or a polygon. Further, the diameter of the cross section is not particularly limited, but for artificial hair, a range of 0.040 mm to 0.100 mm is suitable for a round cross section.

  In addition, as long as the object of the present invention is not hindered, various additives such as a heat-resistant agent, a flame retardant, an antistatic agent, an ultraviolet absorber, and an antioxidant are arbitrarily added to the fluororesin and the polyamide-based resin. Can be contained.

  Next, the manufacturing method of the core-sheath composite monofilament for artificial hair of the present invention will be described in detail.

  First, the core-sheath composite monofilament for artificial hair according to the present invention is mixed with a polyamide resin and a fluororesin with a predetermined amount of color pellets colored with respective resins according to the coloring method, and then supplied to a known melt spinning machine for composites. Then, after melt-kneading in the melt spinning machine, the resin in the core-sheath composite form is extruded from the spinneret hole.

  Next, the extruded melt is continuously introduced into the cooling medium and cooled and solidified. Examples of the cooling medium include water and polyethylene glycol. However, the cooling medium is not particularly limited as long as it can be easily removed from the surface of the monofilament and does not change chemically or physically.

  The unstretched yarn that has been cooled and solidified is subjected to one-stage heating or multi-stage drawing and heat setting in order to obtain the necessary strength as a monofilament. Examples of the heat medium used in this case include air, hot water, steam, polyethylene glycol, glycerin and silicone oil, but they can be easily removed from the surface of the monofilament, and the chemical and physical changes can be made. If it does not give, it will not specifically limit.

  The core-sheath composite monofilament for artificial hair thus obtained is wound up with a finishing oil attached as necessary.

  As described above, the core-sheath composite monofilament for artificial hair of the present invention can form a strong low-friction protective layer by disposing an EFEP resin excellent in adhesiveness with a polyamide-based resin in the sheath layer. The self-lubricating slip characteristics of the material make it very easy to comb and prevent entanglement. In addition, the bending durability, which was a weak point of nylon resin, has been greatly improved, and it has extremely high durability against bending during washing and sleeping. Is realized. In addition, by selecting a coloring method for the core portion and the sheath portion, it is possible to obtain artificial hair with a wide range of variations in glossiness and stereoscopic effect.

  Therefore, the core-sheath composite monofilament for artificial hair of the present invention is a monofilament for artificial hair with high added value that can be suitably used not only for artificial hair but also for doll hair.

  Hereinafter, the core-sheath composite monofilament for artificial hair of the present invention will be described in detail with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist.

  Moreover, the evaluation of the monofilament for artificial hair in an Example was performed with the following method.

[Combination]
Using a commercially available hair brush with 126 plastic combs arranged in a width of 4 cm and a length of 8 cm, brushing an artificial hair bundle with a length of 50 cm and a bundle diameter of 2 cm 30 times, The generation of hair and the entanglement of artificial hair were comprehensively judged. Judgment criteria are as follows.

○: Artificial hair is not entangled, there is no damage such as scratches and deformation,
Δ: Tangled due to generation of static electricity, and damage to artificial hair is observed.
×: Combing evaluation was interrupted due to entanglement or deformation.

[Bending fatigue test]
It measured according to JIS P-8115. Specifically, using a bending fatigue testing machine (MIT Toyo Seiki MIT bending fatigue testing machine), load 0.25 g / d, number of swings 175 times / minute, swing angle of about 270 degrees (each about 135 degrees to the left and right) Under these conditions, the number of times of repeated bending that the obtained monofilament for artificial hair was cut was measured.

[Interfacial peeling evaluation]
The cross section of the sample cut in the above-described bending fatigue resistance test was observed by enlarging 100 times using a digital microscope (VHX-500F) manufactured by KEYENCE CORPORATION.

○: No separation between the core and the sheath is observed,
X: The core part and the sheath part were peeled off and not bonded.

[Example 1]
A resin chip obtained by mixing 5 wt% of a master batch chip in which polyamide resin N6 (M1021 manufactured by Toray Industries, Inc.) and M1021T is colored black is used as a core constituent resin, and EFEP (Daikin Industries, Ltd. RP) is used as a sheath constituent resin. -5000), and these were supplied to a composite melt spinning machine, and melt-extruded at a core cross-sectional area ratio of 80% and a sheath cross-sectional area ratio of 20% from a nozzle in which the core part was embedded in the sheath part. The film was cooled in water, and then stretched 4.0 times under hot water at 60 ° C. and dry heat at 120 ° C., followed by relaxation heat treatment in a 180 hot air atmosphere. The thus obtained circular core-sheath composite monofilament having a diameter of 0.08 mm was wound into a bundle.

[Example 2]
A composite monofilament for artificial hair according to Example 1 except that in Example 1, the core part polyamide resin was not colored and the composition of the master part resin EFEP colored in black was changed to a composition mixed with 5 wt%. Was made. The evaluation results are shown in Table 1.

[Example 3]
A composite monofilament for artificial hair was produced in the same manner as in Example 1 except that both the core and the sheath were colored black by the coloring method shown in Example 1 and Example 2. The evaluation results are shown in Table 1.

[Example 4]
A composite monofilament for artificial hair was produced in the same manner as in Example 1 except that the core cross-sectional area ratio was changed to 90% and the sheath cross-sectional area ratio was changed to 10%. The evaluation results of the obtained monofilament for artificial hair are shown in Table 1.

[Example 5]
A composite monofilament for artificial hair was produced in the same manner as in Example 1, except that the core cross-sectional area ratio was changed to 60% and the sheath cross-sectional area ratio was changed to 40%. The evaluation results of the obtained composite monofilament for artificial hair are shown in Table 1.

[Comparative Example 1]
A composite monofilament for artificial hair was produced in the same manner as in Example 1 except that the core cross-sectional area ratio was changed to 97% and the sheath cross-sectional area ratio was changed to 3%. The evaluation results of the obtained composite monofilament for artificial hair are shown in Table 1.

[Comparative Example 2]
A composite monofilament for artificial hair was produced in the same manner as in Example 1 except that the core cross-sectional area ratio was changed to 20% and the sheath cross-sectional area ratio was changed to 80%. The evaluation results of the obtained composite monofilament for artificial hair are shown in Table 1.

[Comparative Example 3]
In Example 1, a 0.08 mm black monofilament was manufactured using only the core-constituting resin N6. The evaluation results of the obtained monofilament are shown in Table 1.

[Comparative Example 4]
A 0.08 mm black monofilament was produced in the same manner as in Comparative Example 4 except that the core-constituting resin in Comparative Example 3 was changed to EFEP. The evaluation results of the obtained monofilament are shown in Table 1.

  As is clear from the results in Table 1, the monofilament for artificial hair according to the present invention exhibits excellent slipperiness due to the fluororesin layer of the sheath, has good combing, and has excellent bending durability. It has a highly practical core-sheath composite monofilament for artificial hair.

  On the other hand, a monofilament for artificial hair that does not satisfy the conditions of the present invention does not sufficiently exhibit the above effects. For example, a core-sheath composite monofilament for artificial hair having a low cross-sectional area ratio of the ETFE resin in the sheath (Comparative Example 1) When the thickness of the sheath is not sufficient and the comb is repeatedly formed due to insufficient strength, the sheath is cracked and the durability is not excellent. On the other hand, when the sheath is too thick (Comparative Example 2), the characteristics such as flexibility and moisture retention of the polyamide-based resin are lost. In Comparative Example 2, the comb evaluation had to be interrupted.

  The ratio of the cross-sectional area of the core part and the sheath part specified in the present invention, the range of 60:40 to 90:10 is a modified ethylene tetrafluoroethylene copolymer resin having a reactive group with good adhesion to the polyamide resin. It is the range that shows the most excellent characteristics when manufactured as a core-sheath composite monofilament, and the form and performance at the time of manufacture are long-term with respect to combability when used as artificial hair, durability against bending, etc. Can be maintained. In the case where monofilaments are produced only with a polyamide-based resin or a fluorine-based resin that does not have a functional group with good adhesiveness even with other fluorine-based resins having high self-lubricating properties and good sliding properties (Comparative Example 3 and Comparative Example 4), It is not preferred because it does not exhibit excellent properties as hair.

  A feature of the present invention is an unprecedented composite monofilament for artificial hair that takes advantage of the excellent properties of polyamide resins and fluorine resins to overcome weak points such as bending durability.

  ADVANTAGE OF THE INVENTION According to this invention, the artificial hair which utilized the core-sheath composite form effectively can be obtained. More specifically, a core-sheath composite monofilament for artificial hair can be obtained that exhibits excellent slipperiness due to the fluororesin layer of the sheath, has good combing, and has excellent performance in bending durability. Furthermore, by adopting a modified ethylenetetrafluoroethylene copolymer resin having a reactive group as the fluororesin, the monofilament surface is not only in a self-lubricating and slippery state, but also with the polyamide resin in the core. It has a core-sheath structure with a strong adhesive force, and can provide an unprecedented core-sheath composite monofilament for artificial hair with excellent performance to cover the bending durability, which is a weak point of polyamide resin, for the long term. Industrial applicability is extremely high.

Claims (5)

A monofilament having a core-sheath composite structure in which the core part is made of a polyamide-based resin layer and the sheath part has a fluororesin layer, and the ratio of the cross-sectional area of the core part to the sheath part is in the range of 60:40 to 90:10. A core-sheath composite monofilament for artificial hair. The core-sheath composite monofilament for artificial hair according to claim 1, wherein the fluororesin forming the fluororesin layer is a modified ethylenetetrafluoroethylene copolymer resin having a reactive group. The core-sheath composite monofilament for artificial hair according to claim 1 or 2, wherein, in a bending fatigue test measured in accordance with JIS P-8115, the number of reciprocal bending until cutting is 5000 or more. An artificial hair comprising at least a part of the core-sheath composite monofilament for artificial hair according to any one of claims 1 to 3. An artificial hair, wherein a plurality of core-sheath composite monofilaments for artificial hair according to any one of claims 1 to 3 are aligned and fixed to a mesh base fabric.