U.S. patent application number 11/816084 was filed with the patent office on 2009-05-21 for artificial hair and wig using the same.
Invention is credited to Osamu Asakura, Kazumi Il, Akemi Irikura, Hiromi Kojima, Yutaka Shirakashi, Fumitaka Sugawara, Mutsuko Watanabe, Takayuki Watanabe.
Application Number | 20090126749 11/816084 |
Document ID | / |
Family ID | 36916321 |
Filed Date | 2009-05-21 |
United States Patent
Application |
20090126749 |
Kind Code |
A1 |
Shirakashi; Yutaka ; et
al. |
May 21, 2009 |
ARTIFICIAL HAIR AND WIG USING THE SAME
Abstract
An artificial hair and a wig using the same are provided which
have such feeling as appearance, tactile and texture and preferable
physical properties similar to natural hair, wherein an artificial
hair 1 has a sheath and core structure comprising a core portion 1B
and a sheath portion 1A covering said core portion 1B, and by
making the core portion 1B of a polyamide resin, especially a
semi-aromatic polyamide resin, and the sheath portion 1A of a
polyamide resin having a rigidity for bending lower than the core
portion 1B, especially a linear saturated aliphatic polyamide
resin, the rigidity for bending, for example, can be made to have a
value close to that of natural hair, and further its variation
behavior depending upon humidity can be controlled quite similar to
natural hair, thereby the wig made of it as a material has natural
feeling, so that the wig having an excellent appearance can be
offered.
Inventors: |
Shirakashi; Yutaka; (Tokyo,
JP) ; Watanabe; Takayuki; (Tokyo, JP) ;
Asakura; Osamu; (Tokyo, JP) ; Irikura; Akemi;
(Tokyo, JP) ; Il; Kazumi; (Tokyo, JP) ;
Watanabe; Mutsuko; (Tokyo, JP) ; Kojima; Hiromi;
(Tokyo, JP) ; Sugawara; Fumitaka; (Tokyo,
JP) |
Correspondence
Address: |
MASAO YOSHIMURA, CHEN YOSHIMURA LLP
333 W. El Camino Real, Suite 380
Sunnyvale
CA
94087
US
|
Family ID: |
36916321 |
Appl. No.: |
11/816084 |
Filed: |
February 1, 2006 |
PCT Filed: |
February 1, 2006 |
PCT NO: |
PCT/JP2006/301647 |
371 Date: |
December 1, 2008 |
Current U.S.
Class: |
132/56 ;
132/53 |
Current CPC
Class: |
D01F 8/12 20130101; A41G
3/0083 20130101; D01D 10/00 20130101 |
Class at
Publication: |
132/56 ;
132/53 |
International
Class: |
A41G 3/00 20060101
A41G003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 15, 2005 |
JP |
2005-038415 |
Dec 9, 2005 |
JP |
2005-357021 |
Claims
1. An artificial hair having a sheath and core structure comprising
a core portion and a sheath portion covering said core portion,
characterized in that: said core portion is made of a polyamide
resin, and said sheath portion is made of a polyamide resin having
lower rigidity for bending than said core portion.
2. The artificial hair as set forth in claim 1, characterized in
that the surface of said artificial hair is deglossed by having a
fine concave and convex portion.
3. The artificial hair as set forth in claim 2, characterized in
that said fine concave and convex portion is formed by
spherocrystal and/or blast processing.
4. The artificial hair as set forth in claim 1, characterized in
that said core portion is made of a semi-aromatic polyamide resin,
and said sheath portion is made of a linear saturated aliphatic
polyamide resin.
5. The artificial hair as set forth in claim 4, characterized in
that said semi-aromatic polyamide resin is an alternating copolymer
of hexamethylenediamine and terephthalic acid, or an alternating
copolymer of metaxylylene diamine and adipic acid.
6. The artificial hair as set forth in claim 4, characterized in
that said linear saturated aliphatic polyamide resin is a
caprolactam ring-opening polymer, and/or an alternating copolymer
of hexamethylene-diamine and adipic acid.
7. The artificial hair as set forth in claim 1, characterized in
that the sheath and core weight ratio of said sheath and said core
portions is 10/90-35/65.
8. The artificial hair as set forth in claim 1, characterized in
that said artificial hair contains pigment and/or dye.
9. A wig comprising a wig base and artificial hair attached to said
wig base, characterized in that: said artificial hair has a sheath
and core structure comprising a core portion and a sheath portion
covering said core portion, said core portion is made of a
polyamide resin, and said sheath portion is made of a polyamide
resin having lower rigidity for bending than said core portion.
10. The wig as set forth in claim 9, characterized in that the
surface of said artificial hair is deglossed by having a fine
concave and convex portion.
11. The wig as set forth in claim 10, characterized in that said
fine concave and convex portion is formed by spherocrystal and/or
blast processing.
12. The wig as set forth in claim 9, characterized in that said
core portion is made of a semi-aromatic polyamide resin, and said
sheath portion is made of a linear saturated aliphatic polyamide
resin.
13. The wig as set forth in claim 12, characterized in that said
semi-aromatic polyamide resin is an alternating copolymer of
hexamethylenediamine and terephthalic acid, or an alternating
copolymer of metaxylylene diamine and adipic acid.
14. The wig as set forth in claim 12, characterized in that said
linear saturated aliphatic polyamide resin is a caprolactam
ring-opening polymer, and/or an alternating copolymer of
hexamethylene-diamine and adipic acid.
15. The wig as set forth in claim 9, characterized in that the
sheath and core weight ratio of said sheath and said core portions
is 10/90-35/65.
16. The wig as set forth in claim 9, characterized in that said
artificial hair contains pigment and/or dye.
Description
TECHNICAL FIELD
[0001] This invention relates to artificial hair having physical
properties and feeling similar to natural hair and a wig using the
same.
BACKGROUND ART
[0002] Wigs have been manufactured and used since ancient age with
natural hair as the material, but recently such problems as the
supply limitation of natural hair material and others caused the
manufacture to increase using synthetic fibers as hair material for
wigs. In this case, the synthetic fiber to be used is selected with
the primary target that it is basically close to natural hair in
terms of feeling and physical properties.
[0003] The artificial hair materials to be used are synthetic
fibers of acrylic, polyester, and polyamide in many cases, but
acrylic fibers in general have low melting point and poor heat
stability, so that they have such weak points as poor shape
preservation after permanent wave setting, resulting in distortion
of setting, for example, such as curl and the like when soaked in
warm water. Polyester fibers excel in strength and heat stability,
but have too high rigidity for bending, in addition to extremely
low moisture absorbency compared with natural hair, resulting in
appearance, feeling, or physical properties different from natural
hair, for example, in the environment of high humidity, and they
give markedly uncomfortable feeling when used for wigs.
[0004] Here, the rigidity for bending is the property relating to
such feeling as tactile and texture of fibers, and is widely
recognized in fiber and textile industries as such that capable of
numerical expression by KAWABATA method of measurement (See
Non-Patent Reference 1). Also, an apparatus has been developed
which can measure the rigidity for bending using a single strand of
fiber or hair (See Non-Patent Reference 2). Hereinafter rigidity
for bending may be called "bending rigidity", is also called
bending hardness, and is defined as the reciprocal number of
curvature change generated when a unit bending moment is applied to
artificial hair. The larger the rigidity for bending of artificial
hair, the less bendable, the more resistant to bending, that is,
the harder and the less bendable is artificial hair. On the other
hand, the smaller the rigidity for bending, the more bendable and
the softer is artificial hair.
[0005] Since polyamide fibers can offer appearance and physical
properties similar to natural hair in many aspects, they have so
far been in practical use as the hair for wigs, and especially, the
invention by the present applicant of the method of manufacture
which can remove unnatural gloss by surface processing provides
excellent wigs (See Patent Reference 1).
[0006] Polyamide fibers include linear saturated aliphatic
polyamides in which only methylene chains are connected with amide
bonds as a main chain, for example, such as nylon 6 and nylon 66,
and semi-aromatic polyamides in which phenylene units are included
in the main chain, for example, such as nylon 6T of TOYOBO, LTD.
and MXD6 of MITSUBISHI GAS CHEMICAL COMPANY, INC. Patent Reference
1 discloses surface-processed artificial hair of nylon 6 fiber as
the material, but only nylon 6 fiber has the rigidity for bending
lower than natural hair as the property relating to such feeling as
tactile and texture, and hence it is difficult to manufacture the
artificial hair of the same property as natural hair.
[0007] On the other hand, the artificial hair using nylon 6T has
the rigidity for bending higher than the natural hair, and hence it
is difficult to manufacture the hair of the same property as
natural hair. Therefore, it might be considered to manufacture the
fiber having the rigidity for bending close to natural hair by
melt-spinning of nylon 6 and nylon 6T, but these two resins have
too different melting points, and if melting temperature is
determined fitting to nylon 6T of higher melting point, then there
is too serious a problem in the manufacturing process that nylon 6
having low melting point and relatively poor heat stability is
deteriorated by thermal oxidation during melting. Consequently,
nylon 6T has not so far been in practical use as an artificial hair
material.
[0008] The fiber of sheath/core structure is known as a method to
utilize both properties of two kinds of resins. Said fiber
comprises as one strand of fiber a core fiber and a sheath fiber
surrounding it, and can be a generic fiber, or artificial hair
material for wigs, by utilizing respective properties of different
two kinds of resins. For example, Patent Reference 2 discloses the
fiber of sheath/core structure made of vinylidene chloride,
polypropylene, and others, and Patent Reference 3 discloses a
polyamide, but modified fiber by blending protein bridged gel into
the core part.
[0009] Further, in order to prevent the transparency of ordinary
synthetic fibers to cause unnatural gloss when used as artificial
hair, various attempts have been tried to give the appearance and
feeling close to natural hair by making uneven surface to cause
opacity. The above-mentioned Patent Reference 1 discloses the
method of making uneven surface by causing spherocrystal to be
generated and grow, and Patent Reference 4 by treating the fiber
surface with chemical reagents. In addition, also known is the
method of blast-treating of the artificial hair surface with fine
powders such as sand, ice, and dry-ice.
[0010] [Patent Reference 1] JP S64-6114 A (1989)
[0011] [Patent Reference 2] JP 2002-129432 A (2002)
[0012] [Patent Reference 3] JP 2005-9049 A (2005)
[0013] [Patent Reference 4] JP 2002-161423 A (2002)
[0014] [Non-Patent Reference 1] Sen'ikikai Gakkaishi (Journal of
Textile Machine Society, Textile Engineering), Sueo KAWABATA, 26,
10, pp. 721-728, 1973
[0015] [Non-Patent Reference 2] KATOTECH LTD., Handling Manual of
KES-SH Single Hair Bending Tester
DISCLOSURE OF THE INVENTION
Problems to be Solved
[0016] Artificial hair to be used for wigs is required primarily to
have feeling (appearance, tactile and texture) and physical
properties close to natural hair, and in addition, ideally
speaking, the physical properties superior to natural hair. As
mentioned above, various synthetic fiber materials have their own
merits and weak points, respectively, and among them, specific
polyamide fibers, especially nylon 6 and nylon 66, are in practical
use because of their superior properties, but they still have a
problem of having rigidity for bending lower than natural hair.
[0017] An object of the present invention is, in view of the
above-mentioned problems, to provide an artificial hair having
feeling (appearance, tactile and texture) and physical properties
close to natural hair, and a wig using it.
Means to Solve Problems
[0018] The present inventors have completed the present invention,
as the result of strenuous study, by utilizing the characteristics
of polyamide fibers to make a core portion with a polyamide fiber
of high rigidity for bending, and a sheath portion with a polyamide
fiber of the rigidity for bending lower than the core portion, and
by attaining the knowledge that the sheath/core structure, that is,
the structure comprising a core fiber and the sheath fiber
surrounding it, can utilize the characteristics of both resins to
be optimal as an artificial hair of the feeling (appearance,
tactile and texture) and physical properties quite close to natural
hair.
[0019] In order to achieve the above-mentioned object, an
artificial hair of the present invention is characterized to have a
sheath/core structure comprising a core portion and a sheath
portion covering the core portion, wherein the core is made of a
polyamide resin, and the sheath is made of the polyamide resin of
the rigidity for bending lower than the core portion.
[0020] In said structure, the surface of the artificial hair is
preferably deglossed by having fine concave and convex portions.
Fine concave and convex portions may be made by forming
spherocrystal and/or a blast processing. The core portion is
preferably made of a semi-aromatic polyamide resin, and the sheath
portion is made of a linear saturated aliphatic polyamide. A
semi-aromatic polyamide resin is preferably an alternating
copolymer of hexamethylenediamine and terephthalic acid, or an
alternating copolymer of metaxylylenediamine and adipic acid, and a
linear saturated aliphatic polyamide is a caprolactam ring-opening
polymer, and/or an alternating copolymer of hexamethylenediamine
and adipic acid. The sheath/core weight ratio is preferably
10/90-35/65. The artificial hair may contain pigment and/or
dye.
[0021] The artificial hair of the present invention has a double
structure of a core portion and a sheath portion surrounding it,
and since they are made of polyamide resins of different rigidities
for bending, the artificial hair can be provided which has rigidity
for bending quite close to that of natural hair with respect to
humidity change. Therefore, since said artificial hair has the
rigidity for bending close to that of natural hair, natural
artificial hair can be provided which has such feeling as
appearance, tactile and texture quite close to natural hair,
thereby its rigidity for bending changes especially by temperature
and humidity resulting in the behavior close to human hair.
[0022] A wig of the present invention is characterized in that it
comprises a wig base and artificial hair attached or tied to the
wig base, such artificial hair as has a sheath/core structure made
of a core portion and a sheath portion covering the core, the core
portion is made of a polyamide resin, and the sheath portion is
made of a polyamide resin of the rigidity for bending lower than
the core portion.
[0023] By using the artificial hair of the above-mentioned
structure for a wig of the present invention, a wig can be provided
which shows the behavior quite close to that by the rigidity for
bending of natural hair to humidity change. Therefore, since the
artificial hair has good hair standing, and its rigidity for
bending is close to that of natural hair, a wig of natural
appearance, and quite excellent in such feeling as appearance,
tactile and texture can be obtained. Consequently, with the
artificial hair of the rigidity for bending changing in accordance
with temperature and humidity, and showing the behavior closer to
human hair than the conventional hair, such appearance is given
that of the wearer's own hair naturally growing on the head, and
the wearer would not expose the wig wearing.
EFFECT OF THE INVENTION
[0024] According to the present invention, the artificial hair can
be provided which has a sheath/core structure, and has feeling
(appearance, tactile and texture), various physical properties,
especially rigidity for bending and its changing behavior by
humidity close to those of natural hair. Further, the wig using the
artificial hair having said sheath/core structure can provide
natural feeling to the wearer and the surrounding observers more
than the conventional wig using artificial hair made of a single
synthetic fiber material.
[0025] Especially, by making artificial hair of a sheath/core
structure with a sheath portion of a polyamide resin with rigidity
for bending lower than a core portion, the rigidity for bending
changes depending upon temperature and humidity, resulting in the
artificial hair showing the behavior closer to human hair, and by
said artificial hair of the present invention, even when curl is
set, the extension of curl upon wetting with water and recovery of
curl upon removing moisture under natural standing can show the
behavior similar to natural hair.
[0026] Therefore, with the wig of the present invention, when worn
in the rain, or under the environment of high humidity, the
artificial hair softens, hangs down, and its bulkiness disappears,
by the change characteristics of rigidity for bending by moisture
absorption of artificial hair, that is, lowering of rigidity for
bending with humidity rise, and when the absorbed water is released
by natural standing or drying, artificial hair stands up gradually
to return to the original state. As a result, since a wig can be
obtained which shows the same behavior as if natural hair is
growing on a scalp, it can be a wig of excellent appearance, hard
to recognize as a wig.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 diagrammatically illustrates a structure of an
artificial hair in accordance with a first embodiment of the
invention, and (A) is a diagonal view, and (B) is a vertical cross
sectional view in the length direction of the artificial hair.
[0028] FIG. 2 is a cross sectional view in the length direction
diagrammatically illustrating the structure of a modified example
of the artificial hair of the present invention.
[0029] FIG. 3 is a diagrammatical drawing of a spinning machine
used for manufacturing the artificial hair of the present
invention.
[0030] FIG. 4 is a diagrammatical cross sectional view illustrating
an outlet used for a spinning machine.
[0031] FIG. 5 is a diagonal view diagrammatically illustrating the
structure of a wig using artificial hair in accordance with a
second embodiment of the invention.
[0032] FIG. 6 is an enlarged view diagrammatically illustrating the
behavior of the wig of FIG. 5 with respect to humidity change, and
(A) shows an ordinary humidity state, and (B) shows a high humidity
state.
[0033] FIG. 7 is a graph showing the stretching ratio dependency of
rigidity for bending of the artificial hair of Example 3.
[0034] FIG. 8 is an image of the cross section of artificial hair
of Example 2 by an electron microscope.
[0035] FIG. 9 is an image of the surface of artificial hair of
Example 2 by an electron microscope.
[0036] FIG. 10 is an image of the cross section of artificial hair
of Example 3 by an electron microscope.
[0037] FIG. 11 is a cross sectional image of artificial hair having
a sheath/core structure of Comparative Example 3 by an electron
microscope.
[0038] FIG. 12 is a graph showing the humidity dependency of
rigidity for bending of the artificial hairs of Examples 1-5 and
Comparative Examples 1 and 2.
[0039] FIG. 13 is a graph showing the humidity dependency of
rigidity for bending of the artificial hairs of Examples 6-10 and
Comparative Examples 1, 4, and 5.
[0040] FIG. 14 shows photographs of the initial states of curls of
(A) the artificial hair of Example of the present invention, (B)
the natural hair, and (C) the conventional artificial hair made of
polyester.
[0041] FIG. 15 shows photographs of the water-soaked states of (A)
the artificial hair of Example of the present invention, (B) the
natural hair, and (C) the conventional artificial hair made of
polyester.
[0042] FIG. 16 shows photographs of the dried states after
water-soaking of (A) the artificial hair of Example of the present
invention, (B) the natural hair, and (C) the conventional
artificial hair made of polyester.
[0043] 1: Artificial Hair [0044] 1A: Sheath Portion [0045] 1B: Core
Portion [0046] 1C: Fine Concave and Convex Portion [0047] 10:
Artificial Hair Having Fine Concave and Convex Portions on Its
Surface [0048] 21: First Cylinder [0049] 22: Second Cylinder [0050]
21A, 22A: Resin Melt Composition [0051] 21B, 22B: Gear Pump [0052]
23: Discharge Part [0053] 23A: Outer Ring Outlet [0054] 23B: Inner
Circle Outlet [0055] 23C: Outlet [0056] 24: Quenching Bath [0057]
25: First Stretching Roll [0058] 26: First Dry Stretching Bath
[0059] 27: Second Stretching Roll [0060] 28: Second Dry Stretching
Bath [0061] 29: Third Stretching Roll [0062] 30: Third Dry
Stretching Bath [0063] 31: Oiling Device [0064] 32: Fourth
Stretching Roll [0065] 33: Blast Machine [0066] 34: Rollup Machine
[0067] 40: Wig Using Artificial Hair [0068] 41: Wig Base
BEST MODES FOR CARRYING OUT THE INVENTION
[0069] Hereinafter, the present invention will be explained in
details with reference to the embodiments illustrated in the
figures.
[0070] Explanation is first made of an artificial hair in
accordance with the first embodiment of the invention.
[0071] FIG. 1 diagrammatically illustrates the structure of an
artificial hair in accordance with a first embodiment of the
invention, and (A) is a diagonal view, and (B) is a vertical cross
sectional view in the length direction of artificial hair. As is
illustrated, the artificial hair 1 of the present invention has a
sheath/core structure wherein its surface is a sheath portion 1A,
and a core portion 1B is inside the sheath portion 1A. In this case
of illustration here, the sheath/core structure is illustrated with
an example of nearly concentric circular arrangement, but it also
includes the cases where both core 1B and sheath 1A have different
shapes other than nearly concentric circles, for example, the core
is eccentric with regard to the sheath, not being perfectly
concentric circles. It may also be such a sheath/core shape as that
the core is nearly a perfect circle while the sheath has varied
thickness. Also, the cross sectional shape of artificial hair 1 may
be circular, elliptic, or cocoon-shaped.
[0072] As the polyamide resins for the material of said core
portion 1B, semi-aromatic polyamide resins of high strength and
rigidity for bending can be properly used. As said semi-aromatic
polyamide, such may be mentioned as the polymer consisting of an
alternating copolymer of hexamethylenediamine and terephthalic
acid, Nylon 6T for example, expressed in Chemical Formula 1, or the
polymer in which adipic acid and metaxylylenediamine are
alternately bonded, Nylon MXD6 for example, expressed in Chemical
Formula 2.
##STR00001##
[0073] As the polyamide resins for the material of said sheath
portion 1A, polyamide resins of lower rigidity for bending than the
core 1B may be used, and a linear saturated aliphatic polyamide,
for example, can be properly used. As said linear saturated
aliphatic polyamide, such may be mentioned as the polymer
consisting of a ring-opening polymer of caprolactam, Nylon 6 for
example, expressed in Chemical Formula 3, or the polymer consisting
of an alternating copolymer of hexamethylenediamine and adipic
acid, Nylon 66 for example, expressed in Chemical Formula 4.
##STR00002##
[0074] The artificial hair of the present invention 1 has gloss, if
the surface of the sheath 1A is smooth. In order to erase this
unnatural gloss on the surface of artificial hair 1, so-called
deglossing may be applied.
[0075] FIG. 2 is a cross sectional view in the length direction
diagrammatically illustrating the structure of a modified example
of artificial hair of the present invention. As is illustrated, on
the surface of the sheath portion 1A of artificial hair 10, a fine
concave and convex portion 1C is formed. In the case that such a
fine concave and convex portion 1C is formed, diffuse reflection
occurs upon light irradiation to artificial hair 10. Therefore, the
gloss no longer occurs due to the reflection from light irradiation
on the surface of artificial hair, bringing about so-called
deglossing effect.
[0076] Here, the fine concave and convex portion 1C can be given by
blast processing with fine powder such as sand, ice, dry-ice, and
others either during spinning of the artificial hair 1 or on to the
fiber after spinning. In the case during spinning of the artificial
hair 1, it may be by spherocrystal forming on the outermost surface
of artificial hair 1. In this case, it may be the combined
processes of spherocrystal forming and blast processing with fine
powder such as said sand, ice, dry-ice, and others. The concave and
convex portion formed by combination of such spherocrystal
formation and blast processing may be formed to be the concave and
convex portion 1C larger than the order of visible light wavelength
so the light is diffuse reflected.
[0077] The artificial hair 1, 10 of the present invention can be
dyed depending upon the wearer's preference. Said dying may be by
formulating pigment and/or dye during polymer kneading as the
material for spinning, or by dying artificial hair after
spinning.
[0078] According to the artificial hair 1, 10 of the present
invention, by making a sheath/core structure with the polyamide of
high rigidity for bending used for the core 1B, and with the
polyamide of the rigidity for bending lower than the core 1B used
for the sheath 1A, artificial hair can be obtained the rigidity for
bending of which is changed by temperature and humidity, and which
shows behavior closer to the human hair than the conventional
artificial hair. Also, with the artificial hair 10 having the fine
concave and convex portion 1C on the surface of the sheath portion
1A, the deglossing effect is attained, and its properties and
feeling are more approximated to those of artificial hair.
[0079] Explanation is next made of a method of manufacturing
artificial hair in accordance with the present invention.
[0080] FIG. 3 is a diagrammatical drawing of a spinning machine
used for manufacturing the artificial hair of the present
invention, and FIG. 4 is a diagrammatical cross sectional view
illustrating a discharge part used for a spinning machine. As shown
in FIG. 3, a spinning machine 20 comprises a first cylinder 21 of a
polyamide resin for the sheath portion 1A, a second cylinder 22 of
a polyamide resin for the core portion 1B, a discharge part 23 to
discharge the melts 21A, 22A supplied from said cylinders 21, 22, a
quenching bath 24 to solidify the melt thread discharged from an
outlet 23C of the discharge part 23 and to form a concave and
convex portion on the surface, and thereafter via three steps
stretching thermal treatment processing parts with each step
comprising stretching rolls 25, 27, and 29, and dry stretching
baths 26, 28, and 30, a blast machine 33 for forming further the
concave and convex portion 1C on the thread surface, and a rollup
machine 34 to roll up the artificial hair deglossed to the desired
extent with the blast machine 33.
[0081] The cylinders 21, 22 are provided with a heating device to
melt polyamide resin pellets, screws for supplying to a kneader and
the discharge part 23, and gear pumps 21B, 22B to supply the melts
21A, 22A to the discharge part 23.
[0082] The fiber from the outlet 23C of the discharge part 23 goes,
as shown in the figure, via a quenching bath, and stretching and
dry stretching mechanisms, through an oiling device 31 for
electrostatic prevention, a stretching roll 32 to relax the tension
applied on the artificial hair to stabilize dimension, a blast
machine 33 for surface processing, and to a rollup machine 34.
[0083] As shown in FIG. 4, the discharge part 23 is provided with a
concentric circular double outlet from the inner circle part 23B of
which is discharged semi-aromatic polyamide resin melt 22A, and
from the outer ring part 23A surrounding said inner circle part 23B
is discharged linear saturated aliphatic polyamide resin melt 21A,
respectively.
[0084] Explanation is next made of a method of manufacturing the
artificial hair with said spinning machine 20.
[0085] Using said spinning machine 20, artificial hair 1, 10 can be
manufactured by melting each polyamide at appropriate temperature
in cylinders 21, 22, feeding the melts to the discharge part 23,
and by discharging semi-aromatic polyamide resin melt 22A form the
inner circle part 23B of the outlet and linear saturated aliphatic
polyamide resin melt 21A from the outer ring part 23A to make the
thread of sheath/core structure.
[0086] In this case, the ratio of the volume of the linear
saturated aliphatic polyamide resin melt 21A fed for a certain time
with the gear pump 21B and the volume of semi-aromatic polyamide
resin melt 22A fed with the gear pump 22B is defined as sheath/core
volume ratio in the present invention. As described below, in order
to approximate the rigidity for bending of the artificial hair 10
to that of the natural hair, the weight ratio of sheath and core,
the sheath/core weight ratio, is preferably in the range of
10/90-35/65. As the manufacturing condition to obtain said weight
ratio of sheath and core, the sheath/core volume ratio is
preferably 1/2-1/7, and this range is preferred for such properties
as rigidity for bending of artificial hair 1, 10 as mentioned
below. If said sheath/core volume ratio is higher than 1/2, that
is, the ratio of the sheath portion 1A is large, the core portion
1B of artificial hair 1, 10 has small effect to contribute the
increase of rigidity for bending. On the other hand, if said
sheath/core volume ratio is lower than 1/7, that is, the ratio of
the core portion 1B is large, it is not preferred, for the rigidity
for bending becomes too high to be close to the natural hair.
[0087] The stretching ratio may be 5-6 times upon spinning of the
artificial hair 1, 10. Said stretching ratio is about twice as high
as that for the conventional artificial hair of nylon 6 only. For
the artificial hair 1, 10 of the present invention, such as
stretching ratio upon spinning, thread diameter, and rigidity for
bending can be properly determined in accordance with the desired
design. In this case, the shape of sheath/core of artificial hair
1, 10 can be made nearly concentric circular by properly
controlling spinning conditions.
[0088] In the spinning for the artificial hair in accordance with
the present invention, the artificial hair 10 can be manufactured
by forming spherocrystal for the concave and convex portion 1C on
the surface of linear saturated aliphatic polyamide resin as the
sheath portion 1A by passing the thread drawn form the outlet 23C
through the water at 80.degree. C. or higher in the quenching bath
24, thereby giving appearance similar to the natural hair to the
thread, and deglossing to erase an unnatural gloss.
[0089] As methods to form the fine concave and convex portion 1C on
the thread surface, any one of the methods of blasting with such
fine particles as sand, ice, and dry-ice to the thread surface
after spinning, or of chemical treatment of the thread surface, or
proper combination of them may be adopted, in addition to the
above-mentioned spherocrystal formation and growth.
[0090] In order to give the proper color and appearance as the
artificial hair 1, 10, the pigment and/or dye may be formulated
during spinning, or the artificial hair 1, 10 itself may be dyed
after spinning.
[0091] As described above, since the artificial hair 1, 10 of the
present invention has the sheath/core structure with polyamide
resins of different rigidities for bending, the artificial hair 1,
10 of the rigidity for bending higher than that of the conventional
artificial hair of linear saturated aliphatic polyamide resin only
can be manufactured with good reproducibility. Also, by forming the
fine concave and convex portion 1C on the surface of the artificial
hair 1, the natural gloss similar to the natural hair can be given,
thereby so can the natural appearance as hair.
[0092] Explanation is next made of a wig using the artificial hair
in accordance with a second embodiment of the present
invention.
[0093] FIG. 5 is a diagonal view diagrammatically illustrating the
structure of a wig using the artificial hair in accordance with a
second embodiment of the invention. A wig 40 using the artificial
hair 1, 10 of the present invention is that made by tying the
artificial hair 1 or 10 to a wig base 41. The wig base 41 can be
made of either a net base or an artificial skin base. In the case
of the figure, the wig base 41 is shown to be attached or tied to a
mesh of a net member. The wig base 41 may be made by combination of
a net base and an artificial skin base, and there is no special
restriction so far as suitable to wig design or purpose of use.
[0094] The diameter of the artificial hair 1, 10 may be about
0.05-0.1 mm. Also, the artificial hair 10 can be properly used of
which the relative-specular glossiness is suppressed, and which has
gloss similar to natural hair. The color of the artificial hair 1,
10 may be properly chosen according to the wearer's desire such as
black, brown, and blond. Natural appearance is increased if the
artificial hair is chosen of the color fitting to the wearer's own
hair around the part falling out hair. In case of a wig or attached
hair for fashion, the artificial hair of the present invention may
be made mesh-like by giving a color different from the wearer's own
hair, or from a root portion to an end portion, gradation may be
given such as, for example, dark and light tint or color is
gradually changed.
[0095] FIG. 6 is an enlarged view diagrammatically illustrating the
behavior of the wig of FIG. 5 with respect to humidity change, and
(A) shows an ordinary humidity state, and (B) shows a high humidity
state. In the figure, the case is shown where artificial hair is
straight.
[0096] As shown in FIG. 6(A), the artificial hair 1, 10 attached or
tied to the wig 40 of the present invention has rigidity for
bending close to that of the natural hair. Therefore, under the
ordinary environment where the humidity is about 40-60%, the
artificial hair 1, 10 has good standing, and gives bulkiness to the
wig 40.
[0097] On the other hand, when the wig 40 of the present invention
gets wet in the rain, or is worn in the environment of high
humidity, the artificial hair becomes soft, and, as shown in FIG.
6(B), hangs and loses bulkiness, due to the property of changing
rigidity for bending by moisture absorption of the artificial hair
attached or tied to the wig, that is, rigidity for bending is
lowered with humidity increase. Further, when the absorbed water is
released by natural standing or drying, the artificial hair 1, 10
gradually stands up, and returns to the original state.
[0098] Also, if a curl is given to the artificial hair 1, 10, the
curl extends like the natural hair, and, as in the case of straight
hair, it returns to the original state when the absorbed water is
released naturally or by drying.
[0099] With the wig 40 of the present invention, since the
polyamide of high rigidity for bending is used for the core portion
1B, and a polyamide of the rigidity for bending lower than the core
portion 1B for the sheath portion 1A to make the artificial hair 1,
10 of a sheath/core structure, and it is attached or tied to a wig
base, the rigidity for bending is changed by temperature and
humidity, and the wig with good appearance can be obtained which
has feeling or behavior closer to natural hair. Further if the fine
concave and convex portion 1C is formed on its surface as the
artificial hair, it gives appearance closer to natural hair by
deglossing effect.
[0100] Also if the wig 40 of the present invention gets wet in the
rain, or gets moisture with the wearer's sweat, the artificial hair
1, 10 uses the polyamide resin of good water absorption, thereby
absorbs water, hangs down due to its weight increase, and shows the
behavior similar to natural hair. On the other hand, in the case of
a wig using conventional artificial hair, for example, of
polyester, since the rigidity for bending is higher than natural
hair, the wearer's own hair hangs down to a scalp side, whereas the
artificial hair of polyester remains standing upon water absorption
when the wig is worn, and the blended wearer's own hair and the
artificial hair of the wig are combed, thereby separation of the
wearer's own hair and the wig hair of polyester is caused, and
unnatural appearance is given. However, in accordance with the
present invention, since the wig hair hangs down practically as
does the wearer's own hair upon water absorption, no hair
separation is caused, thereby the state can be maintained where the
wearer's own hair and artificial hair are well blended.
EXAMPLES
Example 1
[0101] Explanation is next made in detail of examples of the
present invention.
[0102] Using the spinning machine 20 shown in FIG. 3, the
artificial hair 10 of Example 1 was manufactured. As a polyamide
resin for the core portion 1B, nylon 6T (TOYOBO, LTD.) was used,
and as a polyamide resin for the sheath portion 1A, nylon 6
(TOYOBO, LTD.) was used. For the quenching bath 24, hot water of
80.degree. C. was used. By setting the sheath/core volume ratio as
1/7, and the outlet temperature at 310.degree. C., the artificial
hair 10 was manufactured. The sheath/core weight ratio was 12/88
for the artificial hair 10 of Example 1.
[0103] As a coloring agent, resin chips were used which were made
by blending a polyamide resin used either for said sheath 1A or for
core 1B and a pigment in pre-determined ratio, heating and melting,
and cooling after kneading. These resin chips used as a coloring
agent were defined as the master batch. As the master batch used in
Example, the resin chips containing 3 weight % black inorganic
pigment, the resin chips containing 3 weight % yellow organic
pigment, and the resin chips containing 4 weight % red organic
pigment were used.
[0104] As the concrete details, nylon 6 chips as the material for
the sheath 1A 84 g, a black master batch 5 g, yellow 10 g, red 1 g,
total 100 g of melt resin 21A was first fed into the first cylinder
21 and nylon 6T chips as the material for the core 1B 84 g, a black
master batch 5 g, yellow 10 g, red 1 g, total 100 g of melt resin
22A was fed into the second cylinder 22.
[0105] Nylon 6T was fed with the gear pump 22B to the inner outlet
23B of the discharge part 23, and nylon 6 was fed with the gear
pump 21B to the outer outlet 23A, respectively, and extrusion
volume ratio was made 1/7 as sheath/core ratio by adjusting
rotations of gear pumps 21B and 22B. The spinning machine was that
spun 15 strands of fibers through the outlet of 15 holes.
[0106] The fiber of the sheath/core structure coming out of the
outlet 23C was passed through the quenching bath 24 of 1.5 m length
and was filled with 80.degree. C. warm water to form spherocrystal
on the surface.
[0107] Thereafter, it was drawn by passing through the first
stretching roll 25 and the first dry stretching bath 26 at
180.degree. C., and did heat-set by passing through the second
stretching roll 27 and the second dry stretching bath 28 at
180.degree. C., then annealed for thread diameter size
stabilization by passing through the third stretching roll 29 and
the third dry stretching bath 30 at 185.degree. C., and was passed
through the oiling device 31 for electrostatic prevention.
[0108] As a final step, the fiber surface was made coarse by
blasting fine alumina powder onto the surface through the fourth
stretching roll 32 and the blast machine 33, and rolled up to the
rollup machine 34. The speeds of the first to the fourth stretching
rolls 25, 27, 29, 32 were adjusted so to make stretching ratio 5.5,
and rollup rate 150 m/min in this process.
[0109] All the diameters of thus manufactured artificial hairs 10
were 40-80 .mu.m. The stretching ratio was 5.5 in Example 1, but,
as shown in Example 3 described later, the rigidity for bending of
artificial hair 10 could be adjusted by stretching ratio.
Example 2
[0110] The artificial hair 10 of the sheath/core structure was
manufactured by the same condition as Example 1, except that the
sheath/core volume ratio was made 1/5 by adjusting respective gear
pumps 21B and 22B. The sheath/core weight ratio of the artificial
hair 10 of Example 2 was 16.1/83.9.
Example 3
[0111] The artificial hair 10 of the sheath/core structure was
manufactured by the same condition as Example 1, except that the
sheath/core volume ratio was made 1/3 by adjusting respective gear
pumps 21B and 22B. The sheath/core weight ratio of the artificial
hair 10 of Example 3 was 24.2/75.8, and its diameter was 80
.mu.m.
[0112] FIG. 7 is a graph showing the stretching ratio dependency of
rigidity for bending of the artificial hair 10 of Example 3. In the
figure, an abscissa axis shows a stretching ratio, and an ordinate
axis shows rigidity for bending: 10.sup.-5 gfcm.sup.2/strand. The
measurement condition was temperature 22.degree. C. and humidity
40%. As is obvious from FIG. 7, the rigidities for bending for
stretching ratios 3 and 5.5 were 430.times.10.sup.-5
gfcm.sup.2/strand and 720.times.10.sup.-5 gfcm.sup.2/strand,
showing that rigidity for bending increased linearly with the
increase of stretching ratio.
Example 4
[0113] The artificial hair 10 of the sheath/core structure was
manufactured by the same condition as Example 1, except that the
sheath/core volume ratio was made 1/2 by adjusting respective gear
pumps 21B and 22B. The sheath/core weight ratio of the artificial
hair 10 of Example 4 was 32.3/67.7.
Example 5
[0114] The artificial hair 10 of Example 5 was manufactured by the
same condition as Example 1, except that nylon 66 (MITSUBISHI
ENGINEERING PLASTICS, LTD.) was used as a polyamide resin for the
sheath 1A, and temperature was 92.degree. C. for the quenching bath
24, and 320.degree. C. for the outlet. The sheath/core weight ratio
of the artificial hair 10 of Example 5 was 16.2/83.8.
[0115] The manufacturing conditions of artificial hair of the
above-described Examples 1-5 are shown in Table 1, where all the
diameters of artificial hairs 10 were 40-80 .mu.m.
TABLE-US-00001 TABLE 1 Example 1 2 3 4 5 Resin Core Nylon 6T Nylon
6T Nylon 6T Nylon 6T Nylon 6T Sheath Nylon 6 Nylon 6 Nylon 6 Nylon
6 Nylon 66 Sheath/Core Volume Ratio 1/7 1/5 1/3 1/2 1/5 Outlet
Temp. (.degree. C.) 310 310 310 310 320 Pigment Black 0.15% 0.15%
0.15% 0.15% 0.30% Ratio Yellow 0.30% 0.30% 0.30% 0.30% 0.30% Red
0.04% 0.04% 0.04% 0.04% 0.04% Cooling Water Temp. (.degree. C.) 80
80 80 80 92 Sheath/Core Weight Ratio 12:88 16.1:83.9 24.2:75.8
32.3:67.7 16.2:83.8 of Artificial Hair
Example 6
[0116] The artificial hair 10 of Example 6 was manufactured by the
same condition as Example 1, except that nylon MXD6 (MITSUBISHI GAS
CHEMICAL COMPANY, INC.) was used as a polyamide resin for the core
1B, nylon 6 (MITSUBISHI ENGINEERING PLASTICS, LTD.) was used as a
polyamide resin for the sheath 1A, the temperature for the outlet
was 270.degree. C., and the sheath/core volume ratio was made 1/7.
The sheath/core weight ratio of the artificial hair 10 of Example 6
was 11.8/88.2. For the artificial hair 10 of Example 6, nylon MXD6
was used instead of nylon 6T used for the core 1B of Examples 1-5.
Here, it was drawn using a hot water stretching bath of 95.degree.
C. instead of a first dry stretching bath 26 of Example 1, and did
heat-set in the second dry stretching bath 28 of 150.degree. C.,
annealed for thread diameter size stabilization by passing through
the third stretching roll 29 and the third dry stretching bath 30
at 185.degree. C., and was passed through the oiling device 31 for
electrostatic prevention. The final step to make the fiber surface
of artificial hair coarse was conducted as in Example 1. The speeds
of the first to the fourth stretching rolls 25, 27, 29, 32 were
adjusted so to make stretching ratio 5.6, and rollup rate 150 m/min
in this process. All the diameters of thus manufactured artificial
hairs 10 were in the range between 40 and 80 .mu.m.
Example 7
[0117] The artificial hair 10 of Example 7 was manufactured by the
same condition as Example 6, except that the sheath/core volume
ratio was made 1/5. The sheath/core weight ratio of the artificial
hair 10 of Example 7 was 15.8/84.2.
Example 8
[0118] The artificial hair 10 of Example 8 was manufactured by the
same condition as Example 6, except that the sheath/core volume
ratio was made 1/4. The sheath/core weight ratio of the artificial
hair 10 of Example 8 was 18.9/81.1.
Example 9
[0119] The artificial hair 10 of Example 9 was manufactured by the
same condition as Example 6, except that the sheath/core volume
ratio was made 1/3. The sheath/core weight ratio of the artificial
hair 10 of Example 9 was 23.8/76.2.
Example 10
[0120] The artificial hair 10 of Example 10 was manufactured by the
same condition as Example 6, except that the sheath/core volume
ratio was made 1/2. The sheath/core weight ratio of the artificial
hair 10 of Example 10 was 31.8/68.2. The manufacturing conditions
of the above-described Examples 6-10 are shown in Table 2, where
all the diameters of the artificial hairs 10 were in the range
between 40 and 80 .mu.m.
TABLE-US-00002 TABLE 2 Example 6 7 8 9 10 Resin Core Nylon MXD6
Nylon MXD6 Nylon MXD6 Nylon MXD6 Nylon MXD6 Sheath Nylon 6 Nylon 6
Nylon 6 Nylon 6 Nylon 6 Sheath/Core Volume Ratio 1/7 1/5 1/4 1/3
1/2 Outlet Temp. (.degree. C.) 270 270 270 270 270 Pigment Black
0.18% 0.18% 0.18% 0.18% 0.18% Ratio Yellow 0.45% 0.45% 0.45% 0.45%
0.45% Red 0.04% 0.04% 0.04% 0.04% 0.04% Cooling Water Temp.
(.degree. C.) 80 80 80 80 80 Sheath/Core Weight Ratio 11.8:88.2
15.8:84.2 18.9:81.1 23.8:76.2 31.8:68.2 of Artificial Hair
[0121] Explanation is next made of artificial hairs of Comparative
Examples.
Comparative Example 1
[0122] The thread of diameter 80 .mu.m and stretching ratio 3.3
without sheath structure was manufactured with nylon 6, using the
same spinning machine as Example 1, at the outlet temperature
270.degree. C., and without using the first cylinder 21.
Comparative Example 2
[0123] The thread of diameter 80 .mu.m and stretching ratio 5.5
without sheath structure was manufactured with nylon 6T, using the
same spinning machine as Example 1, at the outlet temperature
310.degree. C., and without using the first cylinder 21.
Comparative Example 3
[0124] The thread of a sheath/core volume ratio 1/1, thread
diameter 80 .mu.m and ratio 5.5 was manufactured with polyester
(TORAY, LTD.) for the core portion 1B, and nylon 6 for the sheath
portion 1A, using the same spinning machine as Example 1, at the
outlet temperature 290.degree. C.
Comparative Example 4
[0125] The thread of diameter 80 .mu.m and stretching ratio 5.6
without sheath structure was manufactured with nylon MXD6 by the
same condition and method as Example 6, using the same spinning
machine as Example 1, at the outlet temperature 270.degree. C., and
without using a first cylinder 21.
Comparative Example 5
[0126] The thread of diameter 80 .mu.m and stretching ratio 5.6
without sheath structure was manufactured with the mixed polyamides
of nylon MXD6 and nylon 6 by the same condition and method as
Example 6, using the same spinning machine as Example 1 at the
outlet temperature 270.degree. C., and without using the first
cylinder 21. The weight ratio of nylon MXD6 and Nylon 6 was 90:10.
The pigment formulation ratio was same in all Comparative Examples
1-5, and that of black, yellow, and red was 0.15%, 0.30%, and
0.04%, respectively. The manufacturing conditions are shown in
Table 3.
TABLE-US-00003 TABLE 3 Comparative Example 1 2 3 4 5 Resin Core
Nylon 6 Nylon 6T Polyester Nylon MXD6 Mixed Polyamide Sheath -- --
Nylon 6 -- -- Sheath/Core Volume Ratio -- -- 1/1 -- -- Outlet Temp.
(.degree. C.) 270 310 290 270 270 Pigment Black 0.15% 0.15% 0.15%
0.15% 0.15% Ratio Yellow 0.30% 0.30% 0.30% 0.30% 0.30% Red 0.04%
0.04% 0.04% 0.04% 0.04% Cooling Water Temp. (.degree. C.) 80 80 80
80 80
[0127] Explanation is next made of the reason why nylon 6T or MXD6
is used for the core 1B of the artificial hair 10, and nylon 6 for
the sheath 1A in Example 1.
[0128] Table 4 shows the humidity dependency of rigidity for
bending, which hereinafter may call "bending rigidity", at
22.degree. C. of the artificial hairs manufactured by using a
single polyamide of nylon 6 in Comparative Example 1, nylon 6T in
Comparative Example 2, and nylon MXD6 in Comparative Example 4. The
rigidity for bending was measured using a single hair bending
tester (KATOTECH, LTD.) as will be described below.
[0129] As is seen in Table 4, the rigidities for bending of
artificial hair of nylon 6 in Comparative Example 1 were
510.times.10.sup.-5 gfcm.sup.2/strand, 340.times.10.sup.-5
gfcm.sup.2/strand, and 250.times.10.sup.-5 gfcm.sup.2/strand,
respectively, at humidity 40, 60, and 80%. Though not shown in the
table, the rigidity for bending and its humidity dependency of
artificial hair using nylon 66 were about the same as those of
nylon 6.
[0130] The rigidities for bending of artificial hair of nylon 6T in
Comparative Example 2 were 980.times.10.sup.-5 gfcm.sup.2/strand,
920.times.10.sup.-5 gfcm.sup.2/strand, and 860.times.10.sup.-5
gfcm.sup.2/strand, respectively, at humidity 40, 60, and 80%.
[0131] The rigidities for bending of the artificial hair of nylon
MXD6 in Comparative Example 4 were 940.times.10.sup.-5
gfcm.sup.2/strand, 870.times.10.sup.-5 gfcm.sup.2/strand, and
780.times.10.sup.-5 gfcm.sup.2/strand, respectively, at humidity
40, 60, and 80%. It is seen from these results that the artificial
hairs using nylon 6T and nylon MXD6 showed higher rigidity for
bending than those using nylon 6 or nylon 66.
[0132] Therefore, it became clear that the artificial hairs of
Examples 1-10 has the core portion 1B made of a polyamide resin
consisting of nylon 6T or nylon MXD6 of high rigidity for bending,
and the sheath portion 1A made of a polyamide resin consisting of
nylon 6 or nylon 66 of lower rigidity for bending than the core
portion 1B.
TABLE-US-00004 TABLE 4 Comparative Example 1 2 4 Resin Nylon 6
Nylon 6T Nylon MXD6 Rigidity for bending 40% 510 980 940 at
22.degree. C. 60% 340 920 870 at Each Humidity 80% 250 860 780
(.times.10.sup.-5 gfcm.sup.2)
[0133] Explanation is next made of various properties of the
artificial hairs manufactured in the above-mentioned Examples 1-10
and Comparative Examples 1-5.
[0134] FIG. 8 is an image of the cross section of artificial hair
of Example 2 by an electron microscope. The electron accelerating
voltage was 15 kV, and magnification was 800. The sheath/core
volume ratio of this artificial hair 10 was 1/5, its diameter 80
.mu.m, and the stretching ratio was 5.5. As is obvious from the
figure, the sheath/core structure was formed with the semi-aromatic
polyamide (nylon 6T) as the core portion 1B and the linear
saturated aliphatic polyamide (nylon 6) as the sheath portion 1A
around it.
[0135] FIG. 9 is an image of the surface of artificial hair of
Example 2 by an electron microscope. The electron accelerating
voltage was 15 kV, and magnification was 700. As is obvious from
the figure, spherocrystals were formed and grew on the linear
saturated aliphatic polyamide, nylon 6, of the surface to give fine
concave and convex portion 1C to the surface.
[0136] FIG. 10 is an image of the cross section of artificial hair
of Example 3 by an electron microscope. The electron accelerating
voltage was 15 kV, and magnification was 900. The sheath/core
volume ratio of this artificial hair 10 was 1/3, its diameter 80
.mu.m, and stretching ratio 5.5. As is seen from the figure, the
sheath/core structure was formed with the semi-aromatic polyamide,
nylon 6T, as the core portion 1B and the linear saturated aliphatic
polyamide, nylon 6, as the sheath portion 1A around it.
[0137] FIG. 11 is a cross sectional image of artificial hair having
the sheath/core structure of Comparative Example 3 by an electron
microscope. The electron accelerating voltage was 15 kV, and
magnification was 300.
[0138] The artificial hair of Comparative Example 3 had the
sheath/core structure consisting of the core portion 1B of
polyester and the sheath portion 1A of linear saturated aliphatic
polyamide, nylon 6. The sheath/core volume ratio was 1/1, the
thread diameter 80 .mu.m, and stretching ratio 5.5. As is seen from
the figure, peeling off was detected at the interface of the core
1B and a sheath 1A, the fiber was white-brownish, and the dyed
color was changed, so that it turned out that such a sheath/core
structure is not suitable to the artificial hair.
[0139] Explanation is next made of the measurement results of
rigidities for bending of the artificial hairs of Examples and
Comparative Examples.
[0140] The rigidity for bending is the physical property applied in
general to fiber and others, and is recognized recently, also for
hair, as the property relating to such feeling as appearance,
tactile and texture etc. As the measurement of the rigidity for
bending of fiber, KAWABATA method and its principle has been well
known for textile, and the rigidity for bending of the artificial
hair was measured using the single hair-bending tester (KATOTECH,
LTD., Model KES-FB2-SH), which applies the method. The measurement
methods in cases of Examples and Comparative Examples of the
present invention for both artificial and natural hairs are such
that bending the whole hair of each one strand of 1 cm as a
circular arc at an equal rate to a certain curvature, detecting a
minute bending moment accompanying it, thereby measuring the
relationship of the bending moment and the curvature. Thus the
rigidity for bending was obtained by bending moment/curvature
change. The representative measurement conditions are shown
below.
(Measurement Conditions)
[0141] Distance between Chucks: 1 cm
[0142] Torque Detector Detection of Torque of Torsion Wire (Steel
Wire)
[0143] Torque Sensitivity: 1.0 gfcm (at Full Scale 10 V)
[0144] Curvature: .+-.2.5 cm.sup.-1
[0145] Rate of Bend Deviation: 0.5 cm.sup.-1/sec
[0146] Measurement Cycle: 1 Round Trip.
Here, a chuck is a mechanism for clipping said each hair of 1
cm.
[0147] FIG. 12 is a graph showing the humidity dependency of
rigidity for bending of the artificial hairs of Examples 1-5 and
Comparative Examples 1 and 2. In the figure, the abscissa axis
shows humidity (%), and the ordinate axis shows rigidity for
bending (10.sup.-5 gfcm.sup.2/strand). The measurement temperature
was 22.degree. C. In FIG. 12, the humidity dependency of rigidity
for bending of the artificial hair of Examples and Comparative
Examples is shown together with that of natural hair. Since natural
hairs have wide personal deviation, hairs were collected from 25
males and 38 females of respective ages between 20 and 50 years
old, rigidities for bending of the samples of 80 .mu.m diameter
were measured, and their average was defined as a standard value.
Their maximum and minimum values were also shown in the figure. It
is seen that the average value of the rigidity for bending of
natural hair was 720.times.10.sup.-5 gfcm.sup.2/strand and
510.times.10.sup.-5 gfcm.sup.2/strand for humidity 40 and 80%,
respectively, and decreases monotonously with humidity
increase.
[0148] On the other hand, the maximum value of rigidity for bending
of natural hair was 740.times.10.sup.-5 gfcm.sup.2/strand and
600.times.10.sup.-5 gfcm.sup.2/strand for humidity 40 and 80%,
respectively, and its minimum value was 660.times.10.sup.-5
gfcm.sup.2/strand and 420.times.10.sup.-5 gfcm.sup.2/strand for
humidity 40 and 80% respectively, and thus the rigidity for bending
of natural hair has wide deviation.
[0149] The artificial hair 10 of Example 1 had a thread diameter of
80 .mu.m, and the sheath/core volume ratio of 1/7. Its rigidity for
bending was 740.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%,
equal to the maximum value of natural hair, and it gradually
decreases with humidity increase, lowering to about
700.times.10.sup.-5 gfcm.sup.2/strand for humidity 60%, and to
about 650.times.10.sup.-5 gfcm.sup.2/strand for humidity 80%.
[0150] From this result, in the case of the artificial hair 10 of
Example 1, it showed higher rigidity for bending than natural hair,
but, compared with the artificial hair of nylon 6 of Comparative
Example 1 and the artificial hair of nylon 6T of Comparative
Example 2 mentioned below, it showed the rigidity for bending and
humidity dependency similar to natural hair.
[0151] The artificial hair 10 of Example 2 had a thread diameter of
80 .mu.m, and the sheath/core volume ratio of 1/5. Its rigidity for
bending was 720.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%,
equal to that of natural hair, and it gradually decreases to about
650.times.10.sup.-5 gfcm.sup.2/strand till humidity 45%. Then it
stayed constant at about 650.times.10.sup.-5 gfcm.sup.2/strand for
humidity between 45 and 60%. In the range of humidity 60-80%,
rigidity for bending gradually decreased to about
600.times.10.sup.-5 gfcm.sup.2/strand for humidity 80%.
[0152] From this result, in the case of the artificial hair 10 of
Example 2, it turned out that the rigidity for bending was equal to
that of natural hair for humidity 40%, and decreased with humidity
increase, thus showing rigidity for bending and humidity dependency
similar to natural hair.
[0153] The difference of artificial hair 10 of Example 3 from
Example 1 is that its sheath/core volume ratio was 1/3. Its
rigidity for bending was 720.times.10.sup.-5 gfcm.sup.2/strand for
humidity 40%, equal to natural hair, decreased in the humidity
range 40-60% to about 520.times.10.sup.-5 gfcm.sup.2/strand for
humidity 60%. In the humidity range 60-80%, it gradually decreased
to about 480.times.10.sup.-5 gfcm.sup.2/strand for humidity
80%.
[0154] From this result, in the case of the artificial hair 10 of
Example 3, it turned out that the rigidity for bending was equal to
that of natural hair for humidity 40%, and decreased with humidity
increase, thus showing the rigidity for bending quite close to that
of natural hair for humidity 80%.
[0155] The difference of artificial hair 10 of Example 4 from
Example 1 was that its sheath/core volume ratio was 1/2. Its
rigidity for bending was 720.times.10.sup.-5 gfcm.sup.2/strand for
humidity 40%, equal to natural hair, decreased in the humidity
range 40-60% to about 510.times.10.sup.-5 gfcm.sup.2/strand for
humidity 60%. In the humidity range 60-80%, it gradually decreased
to about 390.times.10.sup.-5 gfcm.sup.2/strand for humidity
80%.
[0156] From this result, in the case of the artificial hair 10 of
Example 4, it turned out that the rigidity for bending was equal to
that of natural hair for humidity 40%, and decreased with humidity
increase, thus showing the rigidity for bending close to the
minimum value of natural hair for humidity 80%.
[0157] The reason why rigidity for bending of artificial hair 10 of
Examples 2-4 was lower than that of Example 1 for humidity 40% or
higher was that the volume of a sheath portion 1A was higher than
that of Example 1, in another word, the core portion 1B had lower
volume. Therefore, for the artificial hair of the present
invention, the humidity dependency of rigidity for bending can be
changed by changing the sheath/core volume ratio. Thereby, in the
case of artificial hair 10 of Examples 2-4, the rigidity for
bending was equal to that of natural hair for humidity 40%,
decreased with humidity increase, and showed humidity dependency
similar to natural hair.
[0158] The difference of artificial hair 10 of Example 5 from
Example 1 is that its sheath portion was made of nylon 66, and all
others were the same. In Example 5, rigidity for bending was
780.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%, higher than
natural hair, and decreases about linearly in humidity range 40-50%
to about 650.times.10.sup.-5 gfcm.sup.2/strand for humidity 50%. In
humidity range 50-80%, it decreased to about 600.times.10.sup.-5
gfcm.sup.2/strand with the slope about equal to Example 1.
[0159] From this result, in the case of the artificial hair 10 of
Example 5, it turned out that the rigidity for bending was higher
than that of the natural hair for humidity 40%, and decreased with
humidity increase. In the case of the artificial hair 10 of Example
5, the rigidity for bending was higher than Examples 1-4 in
humidity range 40-50%.
[0160] Thereby, in the case of the artificial hair 10 of Example 5
also, the rigidity for bending was close to that of the natural
hair, decreased with humidity increase, and showed the rigidity for
bending and its humidity dependency similar to the natural
hair.
[0161] The artificial hair of Comparative Example 1 was made of
nylon 6, its thread diameter was 80 .mu.m, and stretching ratio was
3.3. In the case of this artificial hair, the rigidity for bending
was about 510.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%,
which was about 70% of natural hair. It decreased about
monotonously with humidity increase to about 250.times.10.sup.-5
gfcm.sup.2/strand for humidity 80%. This value was about 50% of
natural hair. It turned out that the rigidity for bending of
Comparative Example 1 was considerably lower than natural hair or
artificial hair of Examples 1-5 over the whole measured humidity
range.
[0162] The artificial hair of Comparative Example 2 was made of
nylon 6T, its thread diameter was 80 .mu.m, and stretching ratio
was 5.5. In the case of this artificial hair, rigidity for bending
was about 980.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%,
about 136% of natural hair. It decreased about monotonously with
humidity increase to about 860.times.10.sup.-5 gfcm.sup.2/strand
for humidity 80%. This value was about 170% of natural hair. It
turned out that rigidity for bending of Comparative Example 2 was
considerably higher than the natural hair or the artificial hair of
Examples 1-5 over the whole measured humidity range.
[0163] In the case of Comparative Example 3, the peeling off was
caused between the sheath 1A and the core 1B, as mentioned above,
and since it could not be used as the artificial hair, its rigidity
for bending was not measured.
[0164] Explanation is next made of humidity dependency of the
rigidity for bending of artificial hairs of Examples 6-10. FIG. 13
is a graph showing the humidity dependency of the rigidity for
bending of the artificial hairs of Examples 6-10 and Comparative
Examples 1, 4, and 5. In the figure, the abscissa axis shows
humidity (%), and the ordinate axis shows rigidity for bending
(10.sup.-5 gfcm.sup.2/strand). The measurement temperature was
22.degree. C. In FIG. 13, as in FIG. 12, rigidities for bending of
the natural hair were shown as average, maximum, and minimum
values. The difference of the artificial hair 10 of Example 6 from
Example 1 was that its core portion 1B was made of nylon MXD6, its
thread diameter was 80 .mu.m, and the sheath/core volume ratio was
1/7.
[0165] As is seen from FIG. 13, in the case of the artificial hair
10 of Example 6, the rigidity for bending was 730.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, about equal to the average
value of natural hair, and gradually decreased with humidity
increase. It lowered to about 660.times.10.sup.-5 gfcm.sup.2/strand
for humidity 60%, and about 600.times.10.sup.-5 gfcm.sup.2/strand
for humidity 80%.
[0166] From this result, in the case of artificial hair 10 of
Example 6, it turned out that the rigidity for bending was about
equal to that of the natural hair for humidity 40%, decreased with
humidity increase, and shows the behavior similar to natural hair.
That was, the artificial hair 10 of Example 6 showed the rigidity
for bending and its humidity dependency similar to the natural
hair.
[0167] The difference of artificial hair 10 of Example 7 from
Example 6 was that its sheath/core volume ratio was 1/5, and all
others were the same.
[0168] As is seen from FIG. 13, in the case of the artificial hair
10 of Example 7, the rigidity for bending was 730.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, about equal to the average
value of natural hair, and decreased as humidity increased to
around 50% to 620.times.10.sup.-5 gfcm.sup.2/strand. Then it
gradually lowered till humidity 60% to about 610.times.10.sup.-5
gfcm.sup.2/strand for humidity 60%. It further gradually decreased
in humidity range 60-80% to 560.times.10.sup.-5 gfcm.sup.2/strand
for humidity 80%.
[0169] From this result, in the case of the artificial hair 10 of
Example 7, it turned out that the rigidity for bending was about
equal to that of natural hair for humidity 40%, decreased with
humidity increase, and shows the behavior similar to the natural
hair. That was, the artificial hair 10 of Example 7 showed the
rigidity for bending and its humidity dependency similar to the
natural hair.
[0170] The difference of the artificial hair 10 of Example 8 from
Example 6 was that its sheath/core volume ratio was 1/4, and all
others were the same.
[0171] As is seen from FIG. 13, in the case of artificial hair 10
of Example 8, the rigidity for bending was 730.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, about equal to the average
value of the natural hair, and decreased as humidity increased in
humidity range 40-60%, and 560.times.10.sup.-5 gfcm.sup.2/strand
for humidity 60%. Then it gradually lowered in humidity range
60-80% to 490.times.10.sup.-5 gfcm.sup.2/strand for humidity
80%.
[0172] From this result, in the case of the artificial hair 10 of
Example 8, it turned out that the rigidity for bending was about
equal to that of the natural hair for humidity 40%, decreased with
humidity increase, and shows the behavior similar to the natural
hair.
[0173] The difference of the artificial hair 10 of Example 9 from
Example 6 was that its sheath/core volume ratio was 1/3, and all
others were the same.
[0174] As is seen from FIG. 13, in the case of the artificial hair
10 of Example 9, the rigidity for bending was 730.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, about equal to the average
value of natural hair, and decreased as the humidity increased in
humidity range 40-60% to 530.times.10.sup.-5 gfcm.sup.2/strand for
humidity 60%. Then it gradually lowered in humidity range 60-80% to
440.times.10.sup.-5 gfcm.sup.2/strand for humidity 80%.
[0175] From this result, in the case of the artificial hair 10 of
Example 9, it turned out that the rigidity for bending was about
equal to that of the natural hair for humidity 40%, decreased with
humidity increase, and showed the behavior similar to the natural
hair.
[0176] The difference of the artificial hair 10 of Example 10 from
Example 6 was that its sheath/core volume ratio was 1/2, and all
others were the same.
[0177] As is seen from FIG. 13, in the case of the artificial hair
10 of Example 10, rigidity for bending was 730.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, about equal to the average
value of the natural hair, and decreased as the humidity increased
in humidity range 40-60% to 490.times.10.sup.-5 gfcm.sup.2/strand
for humidity 60%. Then it gradually lowered in humidity range
60-80% to 380.times.10.sup.-5 gfcm.sup.2/strand.
[0178] From this result, in the case of the artificial hair 10 of
Example 10, it turned out that rigidity for bending was about equal
to that of the natural hair for humidity 40%, and decreased with
humidity increase. When the humidity exceeded about 60%, the
rigidity for bending of artificial hair 10 was lower than that of
the natural hair, but, compared with the artificial hair of nylon 6
of said Comparative Example 1, or that of nylon MXD6 of Comparative
Example 4 mentioned below, it shows the behavior similar to the
natural hair.
[0179] The artificial hair of Comparative Example 4 was made of
nylon MXD6, its thread diameter was 80 .mu.m, its rigidity for
bending was 940.times.10.sup.-5 gfcm.sup.2/strand for humidity 40%,
and decreased in humidity range 40-60% to 870.times.10.sup.-5
gfcm.sup.2/strand for humidity 60%. It further gradually decreased
till humidity range 60-80% to 780.times.10.sup.-5 gfcm.sup.2/strand
for humidity 80%. It turned out that the rigidity for bending of
Comparative Example 4 was considerably higher than the natural hair
or the artificial hairs of Examples 6-10 over the whole measured
humidity range.
[0180] The artificial hair of Comparative Example 5 was made of
nylon MXD6 with 10% nylon 6 blended in, and its thread diameter was
80 .mu.m. Its rigidity for bending was 870.times.10.sup.-5
gfcm.sup.2/strand for humidity 40%, and decreased till humidity
about 60% to 720.times.10.sup.-5 gfcm.sup.2/strand for humidity
60%. It further gradually decreased till humidity range 60-80% to
610.times.10.sup.-5 gfcm.sup.2/strand for humidity 80%. It turned
out that the rigidity for bending of Comparative Example 5 was
considerably higher than the natural hair or the artificial hairs
of Examples 6-10 over the whole measured humidity range.
[0181] Here, as in FIG. 12, the rigidity for bending of the
artificial hair of Comparative Example 1 is shown together, and it
turned out that it was considerably lower than the natural hair or
the artificial hairs of Examples 6-10 over the whole measured
humidity range.
[0182] As shown in FIG. 12 or 13, the rigidities for bending of
natural hairs tended to have individual deviation, unlike
artificially manufactured hairs, and the humidity dependency of
their rigidities for bending had broad range. The rigidities for
bending of natural hairs by humidity change were in the range of
660.times.10.sup.-5 gfcm.sup.2/strand as its minimum value and
740.times.10.sup.-5 gfcm.sup.2/strand as its maximum value for
humidity 40%, and the width of this deviation was
80.times.10.sup.-5 gfcm.sup.2/strand. For humidity 60%, the minimum
value was 520.times.10.sup.-5 gfcm.sup.2/strand, the maximum value
was 660.times.10.sup.-5 gfcm.sup.2/strand, and the width of
deviation was 140.times.10.sup.-5 gfcm.sup.2/strand which was wider
than for humidity 40%. Further for humidity 80%, the deviation was
wider, as wide as with the minimum value 420.times.10.sup.-5
gfcm.sup.2/strand and the maximum value 600.times.10.sup.-5
gfcm.sup.2/strand.
[0183] According to the artificial hair 10 of Examples 1-10, by
making the sheath with nylon 6 or nylon 66, the core with nylon 6T
or nylon MXD6, and by varying the sheath/core volume ratio, the
artificial hair 10 were obtained which had the rigidity for bending
and its humidity dependency similar to natural hair. As shown in
FIGS. 12 and 13, the rigidity for bending of the artificial hair 10
manufactured using nylon 6T or nylon MXD6 for the core portion 1B
with the sheath/core volume ratio about 1/2 was close to the
minimum value of that of the natural hair, and that of the
artificial hair 10 manufactured with the sheath/core volume ratio
about 1/7 was close to the maximum value of that of the natural
hair.
[0184] With the artificial hair 10 of the sheath/core structure
with the core 1B of the semi-aromatic polyamide resin, and the
sheath 1A of the aliphatic polyamide resin, when the sheath/core
volume ratio was within the range of 1/2-1/7, the artificial hair
was obtained the rigidity for bending of which shows behavior
similar to the natural hair. As shown in Tables 1 and 2, the
sheath/core weight ratio of the artificial hair 10 manufactured by
the sheath/core volume ratio within the range of 1/2-1/7 was in the
range of 10/90-35/65.
[0185] Especially, in the case of the artificial hair 10 of
Examples 6-10 with the sheath of nylon 6 and the core of nylon
MXD6, its rigidity for bending was between the maximum and the
minimum values of the natural hair for humidity 40-50% at
22.degree. C., and showed the behavior similar to its average
value. Further in the humidity range over 50%, the rigidity for
bending of artificial hair 10 of Examples 6 and 7 showed a
characteristic behavior similar to the maximum value of the natural
hair, that of the artificial hair 10 of Example 8 showed a
characteristic behavior similar to the average value of the natural
hair, and that of artificial hair 10 of Examples 9 and 10 showed a
characteristic behavior similar to the minimum value of the natural
hair.
[0186] Explanation is next made of the change of the artificial
hair of Examples by moisture absorption.
[0187] FIGS. 14-16 are figures showing (A) the artificial hair of
Example of the present invention, (B) the natural hair, and (C) the
conventional artificial hair made of polyester in the initial
states of curls, the water-soaked states, and the dried states
after water-soaking, respectively. Each hair was bound at its upper
portion, and drying was by natural drying.
[0188] As shown in FIG. 14, all hairs had the same lengths, and
were in the state of curling with the same curl diameters. It is
seen that, when water-soaked, artificial hairs 1, 10 of Examples
stretch by water absorption, and the change of their lengths was
close to that of the natural hair (See FIGS. 15(A) and (B)). On the
other hand, in the case of the artificial hair using polyester,
since it does not stretch due to low moisture absorbency, it is
seen that curl was not distorted unlike the behavior of natural
hair (See FIG. 15(C)).
[0189] In the dried state after water-soaking, the artificial hairs
1, 10 of Examples recovered to the initial state of curl, and it is
seen that it showed a change close to the natural hair (See FIGS.
16(A) and (B)). Though not shown in figures, in the case of the
artificial hairs made of materials other than polyester, it was
known that their curls stretch upon wetting with water, for
example, and did not recover easily to the original curl even if
the moisture was removed under natural standing.
[0190] Therefore, according to the artificial hairs 1, 10 of the
present invention, it is seen that, when they were curled, their
behavior was close to natural hair in the stretch of curl upon
wetting with water, and the recovery of curl when the moisture was
removed under natural standing.
[0191] According to the artificial hair 10 of the above-mentioned
Examples 1-10, it was seen that the rigidity for bending for
humidity 40% at 22.degree. C. either coincided with the average
value of natural hair 720.times.10.sup.-5 gfcm.sup.2/strand, or
showed a quite close value. It is further seen that the behavior of
the rigidity for bending decreased accompanying humidity increase
up to humidity 80% was also quite close to natural hair. Still
further, it was seen that, for the artificial hair 10 upon actually
wetting with water, the stretch of a curl and its recovery when the
moisture was removed under natural standing are similar behavior to
the natural hair.
Example 11
[0192] Like the artificial hair 10 shown in Examples 1-10, various
artificial hairs 10 with different diameters were made, and a wig
was manufactured therefrom as shown in FIG. 5. It was such a wig
that artificial hairs with different diameters were properly
arranged, having appearance similar to the natural hair by the
design of a curl to a part of hair, thereby the hairline and the
hems of the wig did not have unnatural appearance. According to the
evaluation by the wearer and observers around, feelings, such as
appearance, tactile and texture, was quite natural, and, in the
state of wetting with the rain or shower, the lying state of hair,
the uncurling state, and such feelings as appearance, tactile and
texture did not differ from the wearer's own natural hair, as shown
in FIG. 6 and FIGS. 14-16, hair separation was not caused, thereby
it could be worn quite comfortably.
[0193] According to the above-mentioned Examples, it is seen that
the artificial hair manufactured in accordance with the present
invention had the rigidity for bending for humidity 40% at
22.degree. C. either coinciding with the average value of natural
hair 720.times.10.sup.-5 gfcm.sup.2/strand, or showed a quite close
value, and the behavior of the rigidity for bending decreased
accompanying the humidity increase was also quite close to the
natural hair.
[0194] Therefore, it is seen that, since the wig 40 manufactured
using the artificial hair 1 or 10 of the present invention has
feelings, such as appearance, tactile and texture, similar to
natural hair, and these characteristics change like natural hair
under high humidity, or when wet with water, it can be worn with
natural feeling.
[0195] The present invention is by no way limited to the
above-mentioned Examples, and needless to say that various
modifications are possible within the range of invention as set
forth in the claims, which is also included within the range of the
present invention. For example, polyamide resins may be properly
chosen so that the desired rigidity for bending and others may be
attained.
* * * * *