JP2009028342A - Doll hair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stably provide inexpensive hair for dolls, which has an excellent texture so as to safely and easily enjoy so-called hair styling such as curling, retaining curls, uncurling or the like at body temperature. <P>SOLUTION: A component A is composed of a polyurethane resin having shape memory performance and deformation/recovery (glass transition) temperature of 35-45°C. A component B is composed of a copolymerized polybutylene terephthalate resin having a glass transition point near the deformation/recovery temperature of the component A. The hair for dolls is composed of a sheath core type composite fiber having a core part content of 30-60 wt.%, in which the component A is arranged in a core part and the component B is arranged in a sheath part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to artificial hair used for dolls, children's toys and the like, which can be styled safely and easily at human body temperature and has a texture close to that of natural human hair.

  As artificial hair for dolls, doll hair made of acrylonitrile and vinyl chloride has been developed (Patent Document 1), and doll hair using polypropylene or nylon is widely used. However, since these have high rigidity and become inverted when they are implanted in the head of the doll, it is necessary to perform heat treatment in order to form a state in which the head hangs down along the shape of the head. In addition, in these artificial hairs, improvement in glossiness and curling properties is sought, but in order to express and maintain the shaping effect such as curling, wave, crimping, high temperature heat treatment is necessary, In addition to various thermal hazards, there is a problem that it requires complicated labor. When an infant or the like is used as a toy, there is a disadvantage that hair styling play cannot be performed safely and easily.

For the purpose of improving these problems, an artificial hair molded with a temperature-dependent-shaped material formed by melt blending a thermoplastic resin and a thermoplastic polymer having a glass transition temperature in a specific range at a specific ratio is provided. It has been proposed (Patent Document 2, Patent Document 3, Patent Document 4). These artificial hairs do not require high-temperature heating, and can be shaped by heating means (approximately 50 ° C. or less) in the living temperature range, thereby avoiding the complexity and danger of high-temperature heating means. However, these doll hairs have a drawback that the deformed form such as curls has a short holding time at room temperature and cannot perform the function of holding a favorite hairstyle for a long time. In order to improve the above problem, means <Patent Document 5> for increasing the fiber diameter of the filament made of the blend resin, increasing the secondary moment of section, and improving the shape retention force is further described in the blend resin. A means for improving the shape retention force by using braided or braided filaments (Patent Document 6) is disclosed, but the fiber diameter is 80 to 100 μm (corresponding to 50 to 90 dtex) of human hair. ) Is significantly thicker and inferior in texture.
Japanese Patent Publication No. 5-76880 Japanese Patent Laid-Open No. 10-1545 JP-A-10-118341 JP 2000-178833 A Japanese Patent No. 3756278 JP 2006-28700 A

An object of the present invention is to provide a doll's hair that is excellent in texture and that can safely and easily curl and hold at a human body temperature while enjoying so-called hair styling such as easy release. And
In order to achieve the above object, the present inventors have made extensive studies and as a result, have a shape memory as a base resin and have a deformation / recovery temperature (corresponding to a glass transition temperature) in the vicinity of body temperature. Focused on resin. Fibers consisting only of polyurethane-based resins have mechanical defects such as low strength and high elongation, textured defects such as glare and stickiness, and manufacturing defects such as glue, but shape memory polyurethane The component A using A and the component B using a copolymer polybutylene terephthalate resin having an isophthalic acid unit having a glass transition point in the vicinity of the deformation / recovery temperature of the shape memory polyurethane are combined in a core-sheath shape and fiberized. It was found that a surprising effect was obtained and the above-mentioned object was achieved, and the present invention was achieved.

That is, in the present invention, the component A made of polyurethane resin having shape memory performance is in the core,
The present invention relates to doll hair comprising a core-sheath fiber in which a component B made of a copolymerized polybutylene terephthalate resin having an isophthalic acid unit having a glass transition temperature in the vicinity of the glass transition temperature of the component A is disposed in the sheath. The content rate of the component A in a fiber is the range of 30 wt%-60 wt%, and the glass transition temperature of the component A is the range of 35-45 degreeC. The doll hair can be repeatedly imparted and held, or released, in the temperature range of 30 to 40 ° C. near the human body temperature. The doll hair according to the present invention comprises a copolymer poly having an isophthalic acid unit having a glass transition temperature in the vicinity of the deformation / recovery (glass transition) temperature of the component A, with the component A made of a polyurethane resin having shape memory performance as a core. It is produced by spinning at a draw ratio of 2 to 3 using a melt spinning method so that component B made of butylene terephthalate resin becomes a sheath.

  According to the present invention, doll hair with excellent texture can be curled and held safely and easily at human body temperature, while it can be repeatedly released, and so-called hair styling can be enjoyed safely by infants. I was able to obtain doll hair as a toy.

  An object of the present invention is to provide a function of freely enjoying hair styling at a human body temperature. For this purpose, it is necessary to create a situation where the shape can be given, held, or released at the temperature near the body temperature. This function cannot be created with general-purpose resin alone, and it is necessary to use a resin having shape memory performance. Examples of the resin having shape memory performance include polyurethane resins, ultrahigh molecular weight polyethylene, polyisoprene resins, styrene-butadiene copolymers, and polynorbornene resins. Among these, the polyisoprene resin and the styrene-butadiene copolymer have a shape deformation / recovery temperature (that is, a glass transition temperature) of 67 ° C. and 60 ° C. to 90 ° C., which are higher than the body temperature, respectively. It is not possible to obtain consistency. Polynorbornene-based resins have a shape deformation / recovery temperature of about 35 ° C. and can be deformed at body temperature, but are difficult to mold because they are ultra-high molecular weight.

Among the above resins, when examining ultra high molecular weight polyethylene and polyurethane resin, since the application object of the present invention is hair, considering the molding method, texture, etc., the shape of the molded resin is fibrous. There must be. When ultra high molecular weight polyethylene is used, the obtained fiber has a wire-like appearance and is unfavorable in terms of texture, and the consistency with the object of the present invention cannot be obtained.
On the other hand, in the case of a polyurethane resin, the resin is easily available and the price is relatively low. Since the shape recovery temperature can be arbitrarily set from around room temperature to about 120 ° C., deformation at body temperature is possible. And it is excellent in moldability. Moreover, the resulting fiber is supple. Therefore, the basic requirements of the present invention are satisfied, and the shape memory resin is necessarily preferably a polyurethane resin. In addition, as a polyurethane-type resin which has the shape memory performance used for this invention, ether type, ester type, and ether-ester type | system | group can be used, and it can be used also by 1 type, or 2 or more types of mixtures.
However, when shape memory polyurethane is used alone, mechanical defects such as low strength and high elongation, textured defects such as glare and sticky feel of the resulting fiber, and fiber winding thread sticking The disadvantages occur. For this reason, it is necessary to combine with a substance that does not have rubber elasticity, can ensure strength, has low elongation, and is relatively excellent in slidability. The best mode for that is the core-sheath conjugate fiber shown in the present invention.

  The simplest method for compositing may be quasi-single componentization by melt blending, but shape memory resins have a strong micro-phase separation structure based on intramolecular and intermolecular interactions. It is relatively difficult to make a pseudo one component by blending. Moreover, even if it can be blended, the performance is ensured by the interaction between the molecules and between the molecules, and therefore, the case where the properties greatly change depending on the mixing scale is not preferable. If fibers of core-sheath composite structure or sea-island composite structure are spun, it is simple because it is only necessary to join both molten polymers at the nozzle part. Control is relatively easy and preferable. In particular, the core-sheath composite structure is more preferable in terms of nozzle manufacturing costs and operational stability, and can be said to be the best mode. The shape memory resin must be disposed on the core of the core-sheath composite yarn.

  For the reasons described above, the concept of the core-sheath type two-component composite fiber in which the component A made of the polyurethane resin having shape memory performance in the present invention is arranged in the core portion has been reached. However, if the component A is a polyurethane resin, there is no particular limitation on the composition, but the shape change / recovery temperature must be in the range of 30 to 45 ° C. If it exceeds this temperature range, it cannot be deformed at body temperature. Conversely, if it falls below this temperature range, the room temperature will be close to or higher than the shape recovery temperature even if it is deformed by body temperature. For this reason, the shape cannot be maintained, which is not preferable because it does not meet the object of the present invention.

  Next, the sheath part of the core-sheath composite structure yarn of the present invention, that is, component B will be described. In addition to the above, the component B is required to have a characteristic that the glass transition point of the corresponding resin is present at or below the body temperature or in the vicinity thereof and does not cause interfacial peeling from the polyurethane resin. Considering the above, Component B is a copolymerized polybutylene terephthalate (hereinafter referred to as PBT) having an isophthalic acid unit having a polar group and having a glass transition point near the deformation / recovery (glass transition) temperature of Component A. preferable.

When polyethylene terephthalate or polypropylene terephthalate is used as component B, the extrusion temperature is higher than the extrusion temperature of polyurethane, so extrusion is not possible when the temperature of the nozzle is adjusted to urethane, and conversely, polyurethane is It is not preferable because it decomposes and causes foaming and the like and stable operation cannot be performed. In addition, since the glass transition temperature of the resin is much higher than the body temperature, sufficient curling performance cannot be obtained. Even a copolymer is unsuitable because it has a high glass transition temperature and requires a high degree of stretching in order to obtain sufficient mechanical strength. In ordinary PBT, since the glass transition point is 40 ° C. to 60 ° C., if a suitable polymer is selected, it can be used from this point, but if it is not a copolymer system, the extrusion temperature is higher than the extrusion temperature of polyurethane. Therefore, it cannot be used for the same reason as above.
Polyamide-based resins have glass transition points below body temperature or in the vicinity, but general-purpose nylon-6 and nylon 6,6 are not suitable for use for the same reason as described above due to extrusion temperature problems. In addition, when nylon-12 or the like is used, a fiber with a very good texture can be obtained, but when a form unique to the polyamide-based fiber is given, a phenomenon that becomes difficult to deform occurs, and sufficient curling is imparted, and Therefore, it is not suitable for use because it cannot obtain the release performance.

  On the other hand, if a copolymerized PBT having an isophthalic acid unit is used, a copolymer composition having an extrusion temperature comparable to that of polyurethane is present, so that the above-described troubles during molding can be avoided. Strictly speaking, although slightly different depending on the degree of crystallinity, the glass transition temperature is in the range of about 25 ° C. to 45 ° C. and is almost the same as the shape change / recovery temperature of urethane, which is very preferable. That is, it can be said that only the copolymerized PBT having an isophthalic acid unit can satisfy the object of the present invention. In addition, the yarn obtained by using PBT resin alone can be oriented by body temperature (very gentle habiting with a long cycle) and held or released, but it cannot handle curls with a short cycle. Inferior in flexibility. This can be said to support the need for compounding. At this time, the melting point of the copolymerized PBT having an isophthalic acid unit corresponding to Component B is preferably 185 ° C. or lower. If the temperature exceeds 185 ° C., the melting temperature reaches the decomposition temperature of urethane, and therefore urethane is decomposed at the nozzle portion, which is not preferable.

  Next, the manufacturing method of the hair for dolls of this invention is demonstrated. The core-sheath conjugate fiber of the present invention can be produced as a monofilament or multifilament by a usual melt spinning method using a spinneret for conjugate fiber, but the core-sheath conjugate ratio includes the component A in the conjugate fiber. The rate should not be outside the range of 30% to 60% by weight of the system. When the core content is less than 30% by weight, the curling, retaining, and releasing performance decreases due to the decrease in the amount of the shape memory resin, so that sufficient quality cannot be ensured. This is not preferable because spinning stability is lowered and troubles such as yarn breakage occur frequently.

  After melt spinning by appropriately adjusting the temperature of the extruder, gear pump, die, etc., the yarn is cooled to below the glass transition point and pulled to obtain an undrawn yarn. The obtained undrawn yarn is subjected to drawing, and drawing may be performed by either a direct spinning drawing method or a two-step method. As the stretching method, either a single-stage stretching method or a multi-stage stretching method can be used. However, the draw ratio is preferably in the range of 2 to 3 times. When the draw ratio is below this range, the curl performance is very good, but the strength cannot be ensured, and the fiber is stretched when pulled slowly and cannot be recovered as it is, so that satisfactory quality cannot be ensured. On the other hand, if the draw ratio exceeds this range, a fiber having high strength can be obtained, but this is not preferable because curling and holding performance deteriorate and satisfactory quality cannot be ensured. As the heating method of the fibers in the stretching, setting, and relaxation processes, a heating roller, a heat plate, a steam jet, a hot water tank, or the like can be used, or these can be appropriately used in combination. An oil agent or the like can be applied to the fiber surface as long as the object of the present invention is not impaired.

  The fineness of the obtained composite fiber is preferably in the range of 55 dtex to 77 dtex. When the fineness is less than this range, the curl performance is very good, but the fiber feels too thin and the appearance feels worse. None of them is not preferable because satisfactory quality cannot be ensured. Human hair has a thickness of about 50 to 90 dtex.

  Furthermore, in the production of doll hair of the present invention, in order to further improve the performance and function of the hair, the third component such as an inorganic filler, pigment, lubricant, Add various functional materials such as softeners, antioxidants, weathering stabilizers, antistatic agents, flame retardants, deodorants, antibacterial agents, negative ion deterrents, electromagnetic shielding agents, insect repellents and repellents, and fragrances. And the function can be provided by post-processing.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not restrict | limited at all by these Examples. In addition, the characteristic in an Example was calculated | required with the following evaluation methods.
(1) Tensile strength (g), elongation (%): Using a constant speed extension type tensile tester (Tensilon RTA manufactured by Toyo Baldwin), the sample length was 20 cm, the grip interval was 5 cm, and the tensile speed was 200 m / min. The average value obtained by dividing the load value (g) at the time of cutting by the average fineness (dtex) is the tensile strength (g / dtex), and the average value of the elongation rate (%) at the time of cutting is the elongation (% ). In these formulations, the number of measurements was 10 times.
(2) Spinnability: The number of yarn breaks that occurred for a production amount of 100 kg was measured.
(3) Appearance: A hair bundle having a length of 30 cm and a weight of 15 g was prepared, and 10 judges judged the gloss of the hair bundle by visual observation when left in a room with a humidity of 60% and a temperature of 25 ° C. overnight. Evaluation was made in 5 stages (average score was adopted). 2 points: Similar to human hair, 1 point: Slightly similar to human hair, 0 point: Neither can be said, -1 point: Strong synthetic feeling, -2 point: Glitter

(4) Tactile sensation: A hair bundle having a length of 30 cm and a weight of 15 g was prepared and left for a day and night in a room with a humidity of 60% and a temperature of 25 ° C. Evaluation (adopted average score). 2 points: smooth, 1 point: good, 0 points: Neither can be said, -1 point: slightly sticky, -2 points: solid (5) Brushing property: Create a hair bundle with a length of 30 cm and a weight of 15 g, Ten judges were touched by hand with a 60% humidity and 25 ° C. room temperature overnight, and were combed with a commercially available comb, and the comb was evaluated in five stages (average score adopted). 2 points: very smooth, 1 point: smooth, 0 points: Slightly caught but no problem, -1 point: caught, -2 points: not passed (6) Curl (deformability): 18 fibers with a length of 30 cm The hair bundle was composed of, and the hair bundle was left overnight in a room with a humidity of 60% and a temperature of 25 ° C. Thereafter, the hair bundle was wound around a plastic round bar having a diameter of 1 cm, grasped by hand for 1 minute, and then removed from the bar, 10 judges were evaluated in 5 stages (average score was adopted). 2 points: very good, 1 point: good, 0 point: tolerance, -1 point: bad, -2 point: very bad

(7) Shape retention: A hair bundle having an evaluation exceeding the allowable range in the evaluation of curling properties in (6) is left in a room with a humidity of 60% and a temperature of 25 ° C. for a whole day and night, and the subsequent shape is not collapsed. This was evaluated in 10 stages by 10 judges. ○: Curling is retained, Δ: Somewhat broken but acceptable range, ×: Curled is broken (8) Release / re-deformability: Hair bundles that have been evaluated above the acceptable range in (7) One end was fixed to a metal net, and the weight was suspended from one end of the free end so as not to curl, and heated in an oven at 35 ° C. for 1 minute. The hair bundle after heating was taken out of the oven, the weight was removed, and then 10 judges judged whether or not curl disappeared from the hair bundle. ○: The curl has almost disappeared and a new shape (in this case, a straight line) has been imparted. Δ: The curl has remained somewhat, but it has almost disappeared and is within the allowable range. The shape is not given.

[Example 1]
<Examination of core-sheath ratio in core-sheath composite yarn>
As component A (core part), a mixture of shape memory polyurethane (DIARY-MM3520 manufactured by Diaplex Co., Ltd., deformation / recovery temperature 35 ° C.) and calcium stearate 100 ppm (calculated in phr) was used. As component B (sheath part), 1 phr of a bronze pigment was mixed with isophthalic acid copolymerized PBT (manufactured by Polyplastics, Duranex 400LP, melting point 170 ° C.), and a master batch was prepared according to a conventional method. Component A was dehumidified and dried at 70 ° C. for 12 hours, then supplied to extruder A, and melted and extruded as a core component while raising the temperature from 170 ° C. to 220 ° C. Component B was dehumidified and dried at 100 ° C. for 12 hours, then supplied to Extruder B, and melted and extruded as a sheath component while raising the temperature from 170 ° C. to 200 ° C. The number of revolutions of each extruder and gear pump so that the core component content is 30 wt% (Sample 1), 40 wt% (Sample 2), 50 wt% (Sample Example 3), and 60 wt% (Sample 4). The two were heated from 205 ° C to a diameter of 1.0 mm and spun from a core-sheath composite die with a concentric shape of 36, cooled in a spinning cylinder, oiled, and heated at 90 ° C. A core-sheath composite fiber wound body having a fineness of 66 dtex was obtained by winding through the used stretching and relaxation processes. The total draw ratio at this time was 2.5 times.
The obtained wound body was left for a day and night in a room kept at a predetermined temperature and humidity, and then subjected to various evaluation tests. The results are summarized in Table 1. Each of the obtained doll hairs had a natural texture, and was capable of free hair styling at body temperature and near body temperature.

[Reference Example 1]
<Examination of core-sheath ratio in core-sheath composite yarn>
For comparison, a system in which the core component content is 0 wt% (sample 5), 20 wt% (sample 6), 70 wt% (sample 7), and 100 wt% (sample 8) under the same conditions as in Example 1. Were also spun and subjected to various evaluation tests. However, in the system having a core component content of 0 wt%, the extruder A was set to the same temperature condition as the extruder B, and in the system having a core component content of 100 wt%, the extruder B was set to the same temperature condition as the extruder A. Various evaluation tests for Samples 5 to 8 are summarized in Table 2. Samples 5 to 8 are systems outside the specified range in the present invention. Sample 5 and sample 6 having a core component smaller than the above range cannot secure satisfactory quality due to deterioration of curl performance, and conversely, sample 7 having a core component larger than the above range has excellent curl performance. As a result, the spinning stability deteriorated, making the production difficult. In Sample 8 having no sheath component, the occurrence of many yarn breaks, the deterioration of the mechanical strength balance, and the texture such as appearance, touch, and combing performance were very bad, and satisfactory quality could not be secured. From the above, it has been found that when the core-sheath ratio in the core-sheath composite yarn is outside the range specified in the present application, it is impossible to prepare doll hair that satisfies the object of the present application.

[Example 2]
<Comparison of Deformation / Recovery (Glass Transition) Temperature of Component A>
Sample 9 (using DIARY-MM2520) having a deformation / recovery temperature of Component A of 25 ° C., Sample 10 (using DIARY-MM4520) at 45 ° C., and Sample 11 (using DIARY-MM5520) at 55 ° C. Doll hair was obtained in the same manner as in Example 1 except that the content was fixed at 50 wt%. An evaluation test was carried out using the obtained sample in the same manner as in Example 1, and the results are shown in Table 3. Sample 10 having a deformation / recovery temperature in the range of 35 ° C. to 45 ° C. had a natural texture, free hair styling with body temperature was possible, and satisfactory quality. However, in Sample 9 whose deformation / recovery temperature is about the same as room temperature and Sample 11 whose deformation / recovery temperature is much higher than body temperature, the curl performance is impaired and satisfactory quality cannot be ensured.

Example 3
<Comparison of total draw ratio of fibers>
Except that the core content was 50 wt% and the total draw ratio was 1.1 times (sample 12), 2 times (sample 13), 2.7 times (sample 14), and 3.2 times (sample 15). In the same manner as in Example 1, doll hair was obtained. An evaluation test was performed in the same manner as in Example 1 using the obtained sample, and the results are shown in Table 4. Sample 13 and sample 14 in which the total draw ratio is in the range of 2 to 3 times have a natural texture, can be freely styled with body temperature, and have satisfactory quality. In Sample 12, where the total draw ratio was less than the above range, the curl performance and curl retention were good, but the mechanical performance was remarkably deteriorated, and the texture was also considerably lowered. Furthermore, when the re-deformability was evaluated, a phenomenon that the yarn was unnaturally stretched was also observed, and satisfactory quality could not be obtained. On the other hand, in Sample 15 in which the draw ratio exceeded the above range, there was no particular problem in terms of texture, but spinning stability and curl performance were greatly deteriorated, and satisfactory quality could not be ensured.

Example 4
<Comparison of fineness>
The doll is manufactured in the same manner as in Example 1 except that the core content is 50 wt% and the average fineness is 44 dtex (sample 16), 55 dtex (sample 17), 77 dtex times (sample 18), and 88 dtex (sample 19). Hair for use was obtained. An evaluation test was carried out using the obtained sample in the same manner as in Example 1, and the results are shown in Table 5. Sample 20 and sample 21 having an average fineness in the range of 55 dtex to 77 dtex had a natural texture, and free hair styling according to body temperature was possible, and the quality was satisfactory. The sample 16 thinner than the above range has a slight cat hair feeling, and the evaluation that the sample is too thin, the sample 19 thicker than the above range has a slightly strong bristle feeling, and the evaluation that the curl performance deteriorates due to the thermal conductivity. It was found that none of them was fully satisfactory and there was an optimum range of fiber thickness.

  ADVANTAGE OF THE INVENTION According to this invention, the hair for dolls which is excellent in a texture and can enjoy what is called hair styling, such as giving and holding | curing of curl and holding | maintenance of the curling safely and simply at a human body temperature, is obtained. For this reason, it can be suitably used not only for dolls including children's toys but also for hair ornaments such as hair wigs and extensions.

Claims (5)

  Component A made of polyurethane resin having shape memory performance is placed on the core, and component B made of copolymer polybutylene terephthalate resin having an isophthalic acid unit having a glass transition temperature near the glass transition temperature of component A is placed on the sheath. Doll hair made of core-sheathed fibers.   The doll hair according to claim 1, wherein the content of component A in the fiber is in the range of 30 wt% to 60 wt%.   The doll hair according to claim 1 or 2, wherein the glass transition temperature of component A is in the range of 30 to 45 ° C.   The doll hair according to any one of claims 1 to 3, wherein the curling and the holding or releasing of the curling can be repeated in the temperature range of 30 to 40 ° C near the human body temperature.   Component B made of a copolymerized polybutylene terephthalate resin having an isophthalic acid unit having a glass transition temperature in the vicinity of the glass transition temperature of component A with component A made of polyurethane resin having shape memory performance as the sheath In addition, a method for producing doll hair, comprising spinning at a draw ratio of 2 to 3 by a melt spinning method.