US20060237869A1

US20060237869A1 - Method for producing a fiber for an artificial hair by polyvinyl chloride/acryl-copolymer blends

Info

Publication number: US20060237869A1
Application number: US11/407,410
Authority: US
Inventors: Hyun-Sik Moon; Jee-Won Park
Original assignee: Modtech Co Ltd
Current assignee: Modtech Co Ltd
Priority date: 2005-04-20
Filing date: 2006-04-19
Publication date: 2006-10-26
Also published as: KR100626792B1

Abstract

The present invention relates to a method for producing a fiber for an artificial hair comprising: (a) pre-mixing a polyvinyl chloride resin mixture which contain 90 to 96% by weight of a polyvinyl chloride resin, 3 to 7% by weight of a stabilizer and 1 to 3% by weight of a lubricant at 90 to 140° C., mixing 20 to 80% by weight of a polyvinyl chloride resin mixture and 20 to 80% by weight of acryl-copolymer to obtain a polyvinyl chloride/acryl-copolymer blends composition; (b) melt-extruding said mixed resin composition through an extruder at 100 to 210° C. to obtain a pellet; (c) inputting said pellet into an spinning machine, melt-spinning at 150 to 220° C. to obtain filament; (d) drawing said melt-spinned filament to have a fineness of 20 to 100 denier; and (e) passing said drawn filament through heat-setting machine of 100 to 150° C. to fix the property of the filament.

Description

This application claims the benefit of Korean Patent Application No. 10-2005-32559, filed Apr. 20, 2005, hereby incorporated by reference.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a fiber for an artificial hair and a method for producing the same. More particularly, it relates to a method for producing a fiber for an artificial hair by applying melt spinning process using polyvinyl chloride based resin and acryl-copolymer as a basic source and a fiber for an artificial hair produced from the same. The method for producing according to the present invention is characterized by using the melt spinning process which was impossible to be used in the conventional manufacturing process of modacrylic fiber. The present invention enables to produce a fiber for an artificial hair improving properties by properly incorporating advantages of modacrylic fiber and those of PVC based fiber.

BACKGROUND OF THE INVENTION

Fiber for an artificial hair generally means synthetic fiber used in a wig for alopecia bandage, fashion and make-up, wherein external properties thereof such as the feel, the gloss, and the like are very similar to those of human hair. Fiber for an artificial hair has a fineness of about 50 denier, whereas filament for clothes has a fineness of about 1 to 2 denier. When classifying on the basis of polymers used for producing fiber, modacrylic fiber and polyvinyl chloride based fiber have been used as high quality fibers for artificial hair until now. Low quality fiber for artificial hair have been produced by using polypropylene or polyester, such fibers are very different from human hair in terms of the flame retardancy, the feel and the gloss, and it has been limitedly used for low grade artificial hair because of its poor properties. Thus, in the market for fiber for artificial hair, the said modacrylic and polyvinyl chloride based fibers have been dominantly used.
For using typical modacrylic fiber, a product of Kanekahuchi company in Japan which is sold under the trademark of ‘Kanekalon’ is known, whereas as for typical polyvinyl chloride fiber, a product of Dongyang chemical in Japan sold under the trademark of ‘Toyokalon’ and a product of Modtech company in Korea sold under the trademark mark of ‘Modlon’ are known. Modacrylic fiber and polyvinyl chloride fiber can be produced by properly changing the basic source and other process conditions based on the required properties and purposes thereof. In general, since modacrylic fiber has a lower specific gravity and high heat resistance compared to polyvinyl chloride fiber, it is more frequently used for braids products, for which its volume is comparatively important, whereas polyvinyl chloride fiber is mainly used for wave style, semi-wigs or accessories.
Modacrylic fiber is typically produced by solution spinning process, wherein modacrylic copolymer, in which 40 to 70% by weight of acrylonitrile monomer, 20 to 40% by weight of vinyl chloride monomer and 10 to 20% by weight of acrylate based component for dyeing property or other additives are copolymerized, is spin processed after being solvated in solvent. The modacrylic fiber has advantages of a low specific gravity, a high heat resistance and a homogenous denier deviation, but has disadvantages in that it has a rough feel and that it is unable to provide various colors due to after-dyeing. Particularly, because of the limitation of the modacrylic fiber that it can only be produced only by using the solution spinning process, it can not avoid the problems of high production cost and environmental pollution caused by production processes. Specifically, in the prior art, since ciana (CN) group of component, which is one of the main component of modacrylic fiber, is decomposed immediately after being heated, a melt spinning process cannot be used to produce modacrylic fiber; therefore, as an alternative, only a solution spinning process can be used for production of modacrylic fiber.
On the other hand, polyvinyl chloride fiber is produced by blending 90 to 95% by weight of polyvinyl chloride based resin (polyvinyl chloride resin only or mixture resin, which is prepared by blending a predetermined percentage of chlorinated polyvinyl chloride resin with polyvinyl chloride resin), 4 to 8% by weight of stabilizer, 1 to 2% by weight of lubricant, and appropriate amount of pigment and by extruding it to form a pellet, and then spinning the pellet by using a melt spinning process, and subsequently drawing and heat treating the resultants. Although polyvinyl chloride fiber has disadvantages of having a high specific gravity and poor heat resistance, it has advantages in that its feel and gloss are excellent as well as the ability for producing various colors. Particularly, in contrast to modacrylic fiber, since polyvinyl chloride fiber can be produced by using the melt spinning process without using solvent at the time of spinning process of fiber, it has advantages in that it can be produced environmentally friendly and with comparatively low cost. Although there were cases where polyvinyl chloride fiber was produced by using a conventional solution spinning process, a production method of polyvinyl chloride fiber by using solution spinning process has not been used since 1990 due to its poor ability for producing various colors and low cost effectiveness and the problems of environmental pollution.
As described above, modacrylic fiber and polyvinyl chloride fiber have their own advantages and disadvantages. Therefore, there have been a number of attempts to produce fiber for artificial hair having proper properties for desirable use by controlling various process parameters including basic resources and process conditions starting from basic resin of modacrylic resin or polyvinyl chloride resin. However, so far, no method of producing fiber for artificial hair has been found, which may provide properties and cost effectiveness for production. Thus, the inventors of the present invention carried out a method for producing fiber for artificial hair by using a melt spinning process, and researched and invented the present invention, which can provide a method of producing fiber for artificial hair, featuring the advantages of both modacrylic fiber and polyvinyl chloride fiber.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method for producing a fiber for an artificial hair to improve properties by incorporating the advantage of modacrylic fiber and the advantage of polyvinyl chloride fiber.
It is another object of the present invention to provide a method for producing a fiber for an artificial hair having a high process/economical efficiency and environment friendliness.
It is a further object of the present invention to provide a method for producing a fiber for an artificial hair with properties, such as fineness, strength, ductility, shrinkage rate, heat resistance, specific gravity, and the like, similar to those of modacrylic fiber using melt spinning process.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In order to achieve the above objects, the present invention provides a method for producing a fiber for an artificial hair, comprising the steps of: (a) pre-mixing a polyvinyl chloride resin mixture which contain 90 to 96% by weight of a polyvinyl chloride resin, 3 to 7% by weight of a stabilizer and 1 to 3% by weight of a lubricant at 90 to 140° C. in turbo mixer, and mixing 20 to 80% by weight of a polyvinyl chloride resin 20 to 80% by weight of acryl-copolymer to obtain a polyvinyl chloride/acryl-copolymer blends composition; (b) melt-extruding the said mixed resin composition through an extruder at 100 to 210° C. to obtain a pellet; (c) inputting the said pellet into an spinning machine, melt-spinning at 150 to 220° C. to obtain filament; (d) drawing the said melt-spinned filament to have a fineness of 20 to 100 denier; and (e) passing the said drawn filament through heat-setting machine of 100 to 150° C. to fix the property of the filament.
According to the present invention, in the said polyvinyl chloride resin mixture, a delustering agent, a feel controller, a pigment, an ultraviolet stabilizer or a light stabilizer, may be further included.
According to the present invention, polyvinyl chloride resin contained in the said polyvinyl chloride resin mixture may be polyvinyl chloride resin alone or mixed resin of polyvinyl chloride resin and chlorinated polyvinyl chloride resin. If chlorinated polyvinyl chloride resin is used, its contents may preferable be 10 to 50% by weight based on polyvinyl chloride resin.
According to the present invention, acryl-copolymer mixed with the said polyvinyl chloride resin mixture may be ABS, SAN, transparent ABS, heat resistance SAN, or specially modified SAN. As for each of the copolymers, the content of acrylonitrile monomer unit is preferably 20% by weight or more, the specific gravity is preferably 1.21 or below; the heat resistance is preferably 85° C. or more.
According to the present invention, stabilizer contained in the said polyvinyl chloride resin mixture may preferably be organic tin stabilizer, metal based stabilizer or mixture thereof, wherein its content of is preferably 3 to 7% by weight based on the total resin mixture.
According to the present invention, lubricant contained in the said polyvinyl chloride resin mixture may preferably be a mixture of an external lubricant of any one selected from a group consisting of oxidized polyethylene wax, wax, polyethylene wax, stearic acid, and an internal lubricant of any one selected from a group consisting of high purity alcohol, low fatty acid and metal stearic acid. The content of lubricant mixture is preferably 1 to 3% by weight based on the polyvinyl chloride resin mixture.
According to the present invention, it is preferable to equip a heat cask below nozzle of a spinning machine to decrease melt viscosity of filament, which passes the spinning machine.
Hereinafter, a method for producing according to the present invention and a fiber for an artificial hair produced by the same are described in detail.
The present invention is characterized by using polyvinyl chloride/acryl-copolymer blends composition which is mixed of 20 to 80% by weight of a polyvinyl chloride resin mixture and 20 to 80% by weight of acryl-copolymer as basic source of spinning. The said polyvinyl chloride resin mixture is preferable to comprise 90 to 96% by weight of a polyvinyl chloride resin, 3 to 7% by weight of a stabilizer and 1 to 3% by weight of a lubricant. Also if necessary there may further be a dullustering agent, a feel controller, a pigment, an ultraviolet stabilizer or a light stabilizer and the like. The above blend condition is an important constitution character of the present invention, wherein it acts as an important process parameter in total steps of extruding, melt spinning, drawing and heating.
The contents of above polyvinyl chloride resin mixture and acryl-copolymer are considered to be an important parameter for obtaining the best property by properly incorporating the advantage of modacrylic fiber with the advantage of polyvinyl chloride fiber. In general, if an excessive amount of polyvinyl chloride resin mixture relative to acryl-copolymer is added, it tends to gain the property of conventional polyvinyl chloride resin. If a relatively large amount of acryl-copolymer is used, it tends to have the property of inferior modacrylic fiber. In addition, the attempt to produce fiber similar to the property of modacrylic fiber by excessively increasing relative content of acryl-copolymer has on one hand the risk of making application of melt spinning process in spinning unfeasible. Therefore, the object of attaining the optimum blend condition, which secures the property of fiber to the suitable level and makes applying of melt spinning process feasible, is attained not by some simplistic theoretical calculation, but through many experiments of various parameter adjustments.
According to the present invention, the resin composition is obtained by mixing 20 to 80% by weight of a polyvinyl chloride resin mixture and 20 to 80% by weight of acryl-copolymer. If the polyvinyl chloride resin mixture is more than 80% by weight based on the total polyvinyl chloride/acrylic resin composition, it is not preferable since the specific gravity of fiber is high and the heat resistance is low, similar to that of polyvinyl chloride. If the content is less than 20% by weight, the specific gravity of fiber may be low and the heat resistance may be improved, whereas the flame retardancy and the feel may be poor. The content ratio of acryl-copolymer to polyvinyl chloride resin mixture according to the present invention, that is 2:8 to 8:2 is a desired value confirmed by experiments through various parameter adjustments. More preferably, the ratio of 3:7 to 7:3 can be used.
On the other hand, the polyvinyl chloride resin mixture according to the present invention is characterized in having a polyvinyl chloride resin, a stabilizer and a lubricant.
In the present invention, the said polyvinyl chloride resin uses polyvinyl chloride resin alone or uses a mixed resin of polyvinyl chloride resin and chlorinated polyvinyl chloride resin. When the polyvinyl chloride resin is used as alone or with mixed resin with chlorinated polyvinyl chloride, the content of it is preferably 90 to 96% by weight based on the polyvinyl chloride resin mixture. If the content is less than 90% by weight, a relative content of other component may be increased, thereby making the cost high and the relative heat resistance poor. And if the content is more than 96% by weight, it may be difficult to obtain a homogenous fiber since the property of the polyvinyl chloride resin is deteriorated or a process pressure is increased and the like.
For the said polyvinyl chloride resin, it is preferable to use any one selected from a homopolymer with degree of the polymerization of 1000 to 1100 having good melting viscosity and, a homopolymer with degree of the polymerization of 700 to 800 having a low melt viscosity, or a homopolymer with degree of the polymerization of 1300 to 1700 having a high melt viscosity, or mixtures thereof.
According to one preferable embodiment of the present invention, polyvinyl chloride resin may be a mixture of polyvinyl chloride resin and chlorinated polyvinyl chloride resin. The said chlorinated polyvinyl chloride resin is added in order to improve the mechanical property such as heat shrinkage rate, heat resistance and tensile strength of fiber, and the feel. The chlorinated polyvinyl chloride resin has various types according to the degree of chlorination. It is preferable to use chlorinated polyvinyl chloride resin which has good heat resistance, process ability and flame retardancy, wherein the chlorine content is 60 to 70% by weight and the degree of the polymerization is 600 to 1200. According to the present invention, if the chlorinated polyvinyl chloride resin is added, the content may preferably be 10 to 50% by weight based on polyvinyl chloride resin. When the content of the chlorinated polyvinyl chloride resin is more than 50% by weight based on polyvinyl chloride resin, it is difficult to produce a fiber since it becomes subject to easy deterioration during processing. When the content of the chlorinated polyvinyl chloride resin is less than 10% by weight, it may have the disadvantage of not being able to obtain the preferable mechanical property of the fiber. Preferably, the content of chlorinated polyvinyl chloride resin in the present invention may be 10 to 50% by weight, more preferably 20 to 40% by weight based on polyvinyl chloride resin.
According to the present invention, as for the blend condition of polyvinyl chloride resin mixture, in addition to the polyvinyl chloride resin, the stabilizer and the lubricant further may be comprised. Generally, it is difficult to choose melt spinning process since the polyvinyl chloride is subject to decompose easily near the melting point. The stabilizer is added to prevent decomposition of polyvinyl chloride. In the present invention, it is preferable to use 3 to 7% by weight based on polyvinyl chloride resin. In addition, the lubricant is added to provide flow property to melting material. The content is preferable to use 1 to 3% by weight based on polyvinyl chloride resin mixture. The above content ratio between the stabilizer and lubricant is also an optimum value obtained by the experiment through various parameter adjustments, which enables the use of melt spinning process and improves the property of fiber.
According to the present invention, as for the said stabilizer, it is preferable to use organic tin stabilizer and metal based stabilizer. The organic tin stabilizer may be tin malate, tin laurate, tin malate ester and the like. The tin malate acts to increase the heat resistance during processing thereby improving the long workability. The tin laurate acts to increase the heat resistance and the lubrication property thereby improving the spinning property. The tin malate ester acts to increase the heat resistance. According to the preferable embodiment of the present invention, the above 3 types of stabilizers are used by mixing by constant content ratio. The metal based stabilizer may be Ba based, Ca based, Mg based and the like.
In the present invention, the content of stabilizer in polyvinyl chloride resin mixture is preferable to be adjusted to 3 to 7% by weight. When the content is less than 3% by weight, it is difficult to obtain spinning for a long period of time since the effects of deterioration protection is not sufficient enough. If the content exceeds 7% by weight, the spinning becomes defective due to lack of melting of the polyvinyl chloride resin.
In the present invention the lubricant may preferably be a mixture of external lubricant such as oxidized polyethylene wax, wax, polyethylene wax, stearic acid and the like, and internal lubricant such as high purity alcohol, low fatty acid, metal stearic acid and the like. The content of the lubricant mixture may preferable be 1 to 3% by weight based on polyvinyl chloride resin mixture. The said external lubricant increases the releasing effect from the surface of process machine by reducing affinity of the dissolved resin on the metal surface, and acts to increase the slippage between particles by acting between polyvinyl chloride particles. The said internal lubricant is used to restrain rise of frictional heat by reducing the melt viscosity.
According to the present invention, the spinning process is advanced by polyvinyl chloride resin/acryl-copolymer mixed with the said polyvinyl chloride resin mixture and the appropriate amount of acryl-copolymer as a basic source.
According to preferred one embodiment of the present invention, the said acryl-copolymer may be ABS(Acrylonitrilie-Butadien-Styrene), SAN(Arcylonitirile-Styrene), transparent ABS, heat resistance SAN, copolymer of syndiotactic styrene and acrylonitrile, copolymer of modified SAN styrene maleimid and acrylonitrile and the like. Acryl-copolymer preferably used in the present invention may be a resin, wherein the acrylonitrile unit content is not less than 20% by weight, the heat resistance is not less that 85° C., and the specific gravity is not more than 1.21 and has excellent compatibility with polyvinyl chloride resin. In the present invention, acryl-copolymer added with polyvinyl chloride resin mixture may preferably be 20 to 80% by weight based on total polyvinyl chloride/acryl-copolymer blends composition. When the content is more than 80% by weight, the specific gravity is low and the heat resistance is high whereas the flame retardancy is poor and the feel is smooth unlike that of human hair. On the other hand when the content is less than 20% by weight, the flame retardancy and feel improve, whereas the specific gravity and heat resistance cannot exceed the level of the conventional polyvinyl chloride fiber. In the present invention, it is more preferable to use 30 to 70% by weight of acryl-copolymer.
According to one embodiment of the present of invention, a compatible agent, such as the resin of ethylene vinylacetate(EVA) or polymethylmethacrylate(PMAA) and the like, may be further added in order to increase compatibility of polyvinyl chloride resin mixture and acryl-copolymer.
According to one preferable embodiment of the present of invention, the additive of a delustering agent, a feel controller, a pigment, UV stabilizer or light stabilizer and the like may be added to the above polyvinyl chloride resin mixture. The use of the above additives and the preferable content are known to a person skilled in the art and they can be varied or adjusted suitably according to property of desired final fiber. The pigment can be added in powder form or pigment pellet form depending on the amount of produced fibers. That is, if the specific color fiber produces a large scale, it may preferable be to use pigment in powder form on blending the basic resin for considering the cost effectiveness, whereas if the fiber having various color and type produces, spinning can be advanced by producing pigment pellet having individual color prior to mixing the basic resin.
Obtaining polyvinyl chloride resin/acryl-copolymer blends mixture according to pre-mixing of polyvinyl chloride resin mixture and additional mixing of acryl-copolymer, and then operating melt extrusion at the temperature of 100 to 210° C. thereby producing a pellet are characterized in the present invention. It is much preferable to prepare in not powder form but in pellet form since the carrying and the handling becomes convenient in real fiber production process.
According to the present of invention, inputting the said prepared pellet into extruder then melt spinning at 150 to 220° C. are characterized. That is, the present invention overcome the technical limitation, for which in the past applying melt spinning to the basic resin including acrylonitrile unit, which is the main component of conventional modarcylic fiber, was not attainable. This was possible from carefully considering the proper type and the blend ratio of the polyvinyl chloride resin, the stabilizer and the lubricant as mentioned above. Particularly, in order to maximize the effect of the present invention, it is preferable to equip heat cask below the nozzle of a spinning machine for the purpose of decreasing melt viscosity of filament which passes the spinning machine thereby making the spinning smooth.
This melt spinned filament has 20 to 100 denier of fineness decreasing during drawing step, then the final fiber is produced through heat-setting step at 100 to 150° C.
The process conditions of the above pellet step, melt spinning step, drawing step and heat-setting step are generally known to a person skilled in the art; however, the present invention provides the specific process condition to obtain proper fiber properties through various experiments using the said the basic resin according to the above blend condition.
Hereinafter, the process for producing a fiber for an artificial hair according to the present invention is described in detail.
(Source Blending)
90 to 96% by weight of a polyvinyl chloride resin, 3 to 7% by weight of a stabilizer and 1 to 3% by weight of a lubricant, some other appropriate amount of pigment or a delustering agent are blended at 90 to 140° C. in high-speed or low-speed to prepare polyvinyl chloride resin mixture. Then, the mixture was mixed with acryl-copolymer having high heat resistance in weight ratio of 2:8 to 8:2 to obtain a polyvinyl chloride/acryl-copolymer blends composition. The pigment can be added to the resin mixture in powder form. If necessary, the delustering agent and a compatible agent(EVA or PMMA) can be added as additives.
(Pellet Producing)
The resin composition is fed into extruder for producing pellet heated to 100 to 210° C. for melting, then extruding and cutting to produce pellet. In the process, pigment prepared in pellet form can be added to the extruder with the resin composition separately.
(Spinning)
The extruded pellet is fed into the spinning machine maintained at 150 to 220° C. and spun through spinneret(nozzle) to produce un-drawn filament of about 60 to 200 denier. It is preferable to select different cross sections such as star shape, horse hoof shape, peanut shape, Y shape, C shape and the like as for the shape of nozzle.
(Drawing)
The un-drawn filament is supplied to dry or wet drawn equipment to provide strength and ductility by drawing to suitable denier of 20 to 100, which is proper for a fiber for an artificial hair.
(Drying and Heat-Setting)
The drawn filament is dried by dry equipment of about 85 to 125° C. and the dry drawn filament successively goes through heat equipment of 100 to 150° C. then made heat-setting the fiber property such as strength, ductility and heat shrinkage rate and the like.
The fiber for the artificial hair according to the present invention produced by the above method has different cross sections such as star shape, horse hoof shape, peanut shape, Y shape, C shape and the like. Also, it shows properties of strength of 1.5 to 3.0g/denier of the strength, ductility of 20 to 60%, and heat shrinkage rate of 0.3 to 5.0% at 100° C.
The major property factors of the preferable fiber for the artificial hair comprise, for example, the fineness, the strength, the ductility, the heat shrinkage rate and the flame retardancy and the like. Also, when considering the use of the fiber, the color, the feel and the gloss and the like must express properly in order to be appeared as human hair.
The fineness in the said property factor represents the thickness of the fiber, wherein the fiber for the artificial hair is required to have 30 to 80 denier of fineness similar to the thickness of the human hair. Also, the fineness can be changed according to the producing method and the technical parameter applied. The human hair has an average denier deviation of 5, and it is required to have not more than a denier deviation of 7 in order to use to fiber for the artificial hair. It is known than the modacrylic fiber produced by prior solution spinning process has not more than a denier deviation of 5, the polyvinyl chloride fiber produced by melt spinning process has a range of denier deviation of 7 to 12. In general, the fiber with the denier deviation of not more than 7 can be used for high grade artificial hair; the fiber with the denier deviation of not more than 10 to 12 can be used to accessory; and the fiber with a denier deviation of more than 12 can be used to low grade artificial hair.
Next, the strength of fiber is described. The strength is a property factor for showing how strong the fiber is against tension, wherein the unit is represented by g/denier. The preferable rage of the strength that the fiber for artificial hair must have is not less than 1 g/denier.
The ductility is a property factor for determining how well the fiber is able to elongate, wherein if it has the ductility of not more than 80%, it can be used for artificial hair.
The heat shrinkage rate is a property factor that represents shrinkage rate of fiber at a specific process temperature, wherein it generally represents the shrinkage rate at the test standard temperature of 100° C. The human hair and modacrylic fiber are known to have the shrinkage rate of lees than 1% at 100° C.; and the polyvinyl chloride fiber is known to have the shrinkage rate of 5%. If the heat shrinkage rate is more than 5%, it is not preferable since the artificial hair decreases on washing, drying and perm, then the original shape is changed. The reason for the occurrence of high heat shrinkage is contemplated by either that heat profile is deficient in the producing process of fiber or the molecular orientation is deficient due to low level of drawing magnification.
The modacrylic fiber and polyvinyl chloride fiber show better flame retardancy compared to the human hair. The reason for this is that the human hair itself do not have the flame retardancy, whereas the modacrylic fiber and polyvinyl chloride fiber contain the chlorine that itself has a flame retardancy characteristic.
The color, feel and gloss are very subjective emotional properties. In terms of the color, as consumers' preferences differ, various colors of fiber for an artificial hair, which can satisfy the consumers' preferences, are needed. Fiber for an artificial hair needs to reflect various colors, including fluorescent color, for desired specific use, while providing natural feel like human hair. In order to have various colors, not only adding an appropriate amount of appropriate pigment is a must but also improvement in the process, which can produce fiber cost-effectively according to the production scale volume, is essentially needed. The sense of feel is a factor which is closely related to the cross sectional shape of fiber. Specifically, in the fiber for an artificial hair considering the use for controlling the gloss, the cross sectional shape of fiber is designed generally to show different cross sections such as star shape, peanut shape, hollow shape, Y-shape, and the like. In this case, it is known that the acuter the section angle of a different cross section is, the rougher the feel is. Various kinds of artificial hair ranging from a shining one to a no-lust one are now used according to preference of consumers. In general, regarding artificial hair for black people, shining artificial hair is favored, where concerning artificial hair for white people, no-lust artificial hair is favored. As explained above, when producing fiber for an artificial hair, the gloss of fiber is controlled by incorporating design of the cross sectional shape, adding of a delustering agent, or controlling of physical property of a main material, and the like. The gloss of fiber is measured by a gloss meter. In general, when a gloss value is not more than 30, it is determined as no gloss; when a gloss value is about 50, it is determined as semi gloss; and when a gloss value is not less than 70, it is determined as gloss.
The present invention is described in more detail with examples and comparative examples, but the examples are only illustrative and, therefore, not intended to limit the scope of the present invention.

EXAMPLE 1

100 part by weight of polyvinyl chloride resin having the degree of polymerization of 1000, 20 part by weight of chlorinated polyvinyl chloride resin having the degree of polymerization of 800 as a polyvinyl chloride resin, 3 part by weight of tin malate, 3 part by weight of tin laurate and 1 part by weight of tin maleester which are organic tin based stabilizer as stabilizer, 1 part by weight of calcium stearate, 1 part by weight of fatty acid alcohol and 0.5 part by weight of stearic acid as a lubricant were charged into high speed blend machine, then mixed and stirred to 120° C., then discharged low speed blend machine. 30% by weight of acryl-copolymer wherein the specific gravity is 1.07 and the heat resistance is 90° C. was added to 70% by weight the said discharged polyvinyl chloride resin mixture, then stirred to obtain a polyvinyl chloride/acryl-copolymer blends composition. The said resin composition was introduced to the extruder which is heated to 150° C. and has good blending property, melted, then extruded and cut to produce a pellet. A color pellet, which is made of pigment, was added to the said pellet, then inputted into the spinning machine with a diameter of 55 mm having a peanut shaped cross section nozzle and thermo heat cask below the nozzle, and melt spun at 200° C. to produce non-drawn filament of 180 denier. The non-drawn filament was wet-drawn to have the fineness of 50 denier and then passed through heat setting room maintained at 135° C. to produce a fiber for an artificial hair with peanut-shaped cross section.

EXAMPLE 2

A fiber for an artificial hair with C-shaped cross-section was produced by conducting the same as in Example 1 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 50% by weight of polyvinyl chloride resin and 50% by weight of acryl-copolymer and spinning in an spinning machine with C-shaped nozzle cross section.

EXAMPLE 3

A fiber for an artificial hair with Y-shaped cross-section was produced by conducting the same as in Example I of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 30% by weight of polyvinyl chloride resin and 70% by weight of acryl-copolymer, and spinning in a spinning machine with Y-shaped nozzle cross section.

EXAMPLE 4

100 part by weight of polyvinyl chloride resin having the degree of polymerization of 1000 as a polyvinyl chloride resin, 2 part by weight of tin malate, 2 part by weight of tin laurate which are organic tin based stabilizer and Ba stabilizer, 1 part by weight of calcium stearate, 1 part by weight of fatty acid alcohol and 0.5 part by weight of stearic acid as a lubricant, 2 part by weight of pigment and 0.5 part by weight of titanium dioxide as a delustering agent were charged into high speed blend machine, then mixed and stirred at 120° C., then discharged to low speed blend machine. 30% by weight of acryl-copolymer in which the specific gravity is 1.20 and the heat resistance is 120° C. was added to 70% by weight of the said polyvinyl chloride resin mixture, then stirred to obtain a polyvinyl chloride/acryl-copolymer blends composition. The said resin composition was introduced to the extruder, which was heated to 150° C. and has a good kneading property, melted, then extruded and cut to produce a pellet. The above pellet was introduced into the spinning machine with a diameter of 55 mm having a peanut shaped cross section nozzle and thermo heat cask below the nozzle, and melt spun at 200° C. to produce un-drawn filament of 180 denier. The un-drawn filament was dry drawn to have the fineness of 50 denier and then passed through heat setting room maintained at 135° C. to produce a fiber for an artificial hair with peanut-shaped cross section.

EXAMPLE 5

A fiber for an artificial hair with C-shaped cross-section was produced by conducting the same as in Example 4 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 50% by weight of polyvinyl chloride resin and 50% by weight of acryl-copolymer, and spinning in an spinning machine with C-shaped nozzle cross section.

EXAMPLE 6

A fiber for an artificial hair with Y-shaped cross-section was produced by conducting the same as in Example 1 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 30% by weight of polyvinyl chloride resin and 70% by weight of acryl-copolymer, and spinning in a spinning machine with Y-shaped nozzle cross section.

COMPARATIVE EXAMPLE 1

A fiber for an artificial hair with star-shaped cross-section was produced by conducting the same as in Example 1 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 90% by weight of polyvinyl chloride resin and 10% by weight of acryl-copolymer, and spinning in a spinning machine with star-shaped nozzle cross section.

COMPARATIVE EXAMPLE 2

A fiber for an artificial hair with H-shaped cross-section was produced by conducting the same as in Example 1 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 10% by weight of polyvinyl chloride resin and 90% by weight of acryl-copolymer, and spinning in a spinning machine with H-shaped nozzle cross section.

COMPARATIVE EXAMPLE 3

A fiber for an artificial hair with star-shaped cross-section was produced by conducting the same as in Example 4 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 90% by weight of polyvinyl chloride resin and 10% by weight of acryl-copolymer, and spinning in a spinning machine with star-shaped nozzle cross section.

COMPARATIVE EXAMPLE 4

A fiber for an artificial hair with H-shaped cross-section was produced by conducting the same as in Example 4 of the present invention, except for using the polyvinyl chloride/acryl-copolymer blends composition consisting of 10% by weight of polyvinyl chloride resin and 90% by weight of acryl-copolymer, and spinning in a spinning machine with H-shaped nozzle cross section.

The Table 1 below shows the resulting properties of a fiber for an artificial hair produced according to the above examples and comparative examples. In particular, in the following Table 1, the property of a fiber for an artificial hair produced according to the example of the invention are shown by comparing with the trademark product of ‘Kanekalon’, which is modarcylic fiber, and the trademark products, ‘Toyokalon’ and ‘Modlon’, which are polyvinyl chloride fibers.

TABLE 1


		Heat
Shape		resistance				Shrinkage
of		By		Strengh		rate
cross	Specific	DSC	Fineness	(g/	Ductility	at	Flame
section	gravity	(° C.)	(De)	De)	(%)	100° C.	retardancy	processibility	Gloss

Example 1	Penut	1.32	84	50	1.9	60	5.0	Not	Good	Semi
	shape							inflammable		gloss
										(50)
Example 2	C	1.26	86	50	2.0	55	3.0	Not	Good	gloss
	shape							inflammable		(70)
Example 3	Y	1.18	88	50	2.0	50	3.0	Not	Good	gloss
	shape							inflammable		(80)
Example 4	Penut	1.34	92	50	2.1	60	1.0	Not	Good	No
	shape							inflammable		gloss
										(30)
Example 5	C	1.30	100	50	2.1	55	0.0	Not	Good	Semi
	shape							inflammable		gloss
										(50)
Example 6	Y	1.26	108	50	2.3	50	0.0	Not	Good	gloss
	shape							inflammable		(70)
Com.	Star	1.38	82	50	1.9	70	5.0	Not	Good	Semi
Example 1	shape							inflammable		gloss
										(50)
Com.	H	1.12	89	50	2.0	50	1.0	Inflammable	Good	gloss
Example 2	shape									(70)
Com.	Star	1.38	84	50	2.0	70	5.0	Not	Good	No
Example 3	Shape							inflammable		gloss
										(30)
Com.	H	1.22	116	50	2.5	50	0.0	Inflammable	Good	gloss
Example 4	Shape									(70)
Kanekalon	C	1.28	95	45	2.0	40	1.0	Not	Good	No
(modacryl)	shape							inflammable		gloss
										(30)
Modlon	Star	1.40	75	50	1.5	80	5.0	Not	Good	No
(PVC)	Shape							inflammable		gloss,
										gloss
										(30˜70)
Toyokalon	Penut	1.40	80	50	1.5	70	5.0	Not	Good	No
(PVC)	shape							inflammable		gloss,
										gloss
										(30˜70)

As shown in Table 1, the fiber for an artificial hair according to the examples of the present invention has an excellent process-ability, a specific gravity of 1.18 to 1.32, a heat resistance in the range of 84 to 108° C. Then it is capable of having a number of physical properties depending on the blend rate, and even has an advantage of being able to freely control the specific gravity, the main physical property, the heat resistance, and the shrinkage rate depending on the kinds of acryl-copolymer. Therefore, it can be used for a greater number of purposes than the conventional polyvinyl chloride and modacryl.
In the specific gravity characteristic which determines the volume of a wig, since the artificial hair fiber is capable of producing fiber with lower specific gravity than the modacrylic fiber shown in the examples 2, 3 and 6, it may advantageously be applied to the kinds of wigs in which large volume is preferred. However, if the content of polyvinyl chloride is 90% such as those in the comparative examples 1 and 3, the specific gravity being 1.38, is not much different from the conventional PVC fiber, thus the effect of improved volume is small.
The flame retardancy is one that determine self-extinguishing by igniting the fiber at room temperature and pressure. If the content of the acryl-copolymer such as those in the comparative examples 2 and 4 is 90%, since fiber loses the self-extinguishing, it is not suitable for high grade wigs that human may wear. Instead, it may be used for low grade fiber such as the puppet types(puppets or manikins).
The process-ability of wig, defined to indicate all of loss, brushing and curling, whereby it is obtained by having several anonymous wig manufacturers to produce wigs, is similar to the conventional polyvinyl chloride fiber and modacryl.
As the gloss changes depending on the purpose of wig, the cases shown in the examples 2, 3 and 6 and the comparative examples 2 and 4 are suitable for wigs for black people and accessories, which require sufficient amount of gloss, and those shown in the examples 1, 4 and 5 and the comparative examples 1 and 3 are of the gloss level used for wigs for white people and accessories.
In terms of other characteristics, such as the strength, the ductility and the shrinkage rate at 100° C., it is similar to the conventional modacrylic fiber, and shows improvement when compared to polyvinyl chloride. The feel and color are superior when compared to modacrylic fiber and is at the same level with polyvinyl chloride fiber for they adopt the same production method.
The producing method according to the present invention allows the application of the melt spinning process by delicately designing the complete manufacturing steps, which include blend condition to significantly enhance process efficiency and environment friendliness and facilitate the manufacturing of advanced artificial hair fiber that comprises various property, of which artificial hair fiber should have, namely, the advanced characteristics that the conventional polyvinyl chloride fiber, which is good flame retardance fiber, and modacrylic fiber have.

Claims

1. A method for producing a fiber for an artificial hair comprising the steps of:

(a) pre-mixing a polyvinyl chloride resin mixture which contains 90 to 96% by weight of a polyvinyl chloride resin, 3 to 7% by weight of a stabilizer and 1 to 3% by weight of a lubricant at 90 to 140° C., mixing 20 to 80% by weight of said polyvinyl chloride resin mixture and 20 to 80% by weight of acryl-copolymer to obtain a polyvinyl chloride/acryl-copolymer blends composition;

(b) melt-extruding said mixed resin composition through an extruder at 100 to 210° C. to obtain a pellet;

(c) inputting said pellet into a spinning machine, melt-spinning at 150 to 220° C. to obtain filament;

(d) drawing said melt-spinned filament to have a fineness of 20 to 100 denier; and

(e) passing said drawn filament through heat-setting machine of 100 to 150° C. to fix the property of the filament.

2. The method for producing a fiber for an artificial hair according to claim 1, wherein said polyvinyl chloride resin mixture further comprises a dullustering agent, a feel controller, a pigment, a ultraviolet stabilizer or a light stabilizer.

3. The method for producing a fiber for an artificial hair according to claim 1, wherein said polyvinyl chloride resin in the polyvinyl chloride resin mixture is polyvinyl chloride resin alone or mixed resin of polyvinyl chloride resin and chlorinated polyvinyl chloride resin.

4. The method for producing a fiber for an artificial hair according to claim 3, wherein said chlorinated polyvinyl chloride resin comprises an amount of 10 to 50% by weight based on the polyvinyl chloride resin.

5. The method for producing a fiber for an artificial hair according to claim 1, wherein said acryl-copolymer is selected from a group consisting of ABS, SAN, transparent ABS, heat resistant SAN and specially modified SAN.

6. The method for producing a fiber for an artificial hair according to claim 1, wherein said acryl-copolymer has a specific weight of 1.21 or below and a heat resistance of 85 or more.

7. The method for producing a fiber for an artificial hair according to claim 1, wherein said stabilizer is organic tin stabilizer, metal based stabilizer or mixture thereof.

8. The method for producing a fiber for an artificial hair according to claim 1, wherein said lubricant is a mixture of an external lubricant selected from a group consisting of oxidized polyethylene wax, wax, polyethylene wax, stearic acid, and an internal lubricant selected from a group consisting of high purity alcohol, low fatty acid and metal stearic acid.

9. The method for producing a fiber for an artificial hair according to claim 1, and further comprising a heat cask is equipped below a nozzle of said spinning machine to decrease melt viscosity of said filament which passes said spinning machine.

10. A fiber for an artificial hair produced by the method of claims 1, 2, 3, 4, 5, 6, 7, 8, or 9.