U.S. patent application number 12/162609 was filed with the patent office on 2008-12-25 for artificial hair, wig using the same, and method of making artificial hair.
Invention is credited to Osamu Asakura, Kazumi Il, Nobuyoshi Imai, Akemi Irikura, Hiromi Kojima, Yutaka Shirakashi, Mutsuko Watanabe, Takayuki Watanabe.
Application Number | 20080314402 12/162609 |
Document ID | / |
Family ID | 38309164 |
Filed Date | 2008-12-25 |
United States Patent
Application |
20080314402 |
Kind Code |
A1 |
Shirakashi; Yutaka ; et
al. |
December 25, 2008 |
Artificial Hair, Wig Using the Same, and Method of Making
Artificial Hair
Abstract
An artificial hair bundle (10) is made up by mixing a first
artificial hair made of a polyester resin (1, 2) and a second
artificial hair made of a polyamide resin (5, 6), and the first
artificial hair (1, 2) is made of polyethylene terephthalate and
polybutylene terephthalate, having a cross-sectional size and
bending rigidity similar to those of natural hair, wherein the
bending rigidity is in the range of about 6.5 to
7.8.times.10.sup.-3 gfcm.sup.2/strand at humidity 40%, and the
first artificial hair (1, 2) suppresses bundling of the second
artificial hair (5, 6), and the first and the second artificial
hairs (1, 2, 5, 6) behave similarly to natural hair.
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) ; Imai; Nobuyoshi; (Tokyo,
JP) |
Correspondence
Address: |
MASAO YOSHIMURA, CHEN YOSHIMURA, LLP
1101 PENNSYLVANIA AVE. NW, 6TH FLOOR
WASHINGTON
DC
20004
US
|
Family ID: |
38309164 |
Appl. No.: |
12/162609 |
Filed: |
January 23, 2007 |
PCT Filed: |
January 23, 2007 |
PCT NO: |
PCT/JP2007/050984 |
371 Date: |
July 30, 2008 |
Current U.S.
Class: |
132/201 ; 132/53;
132/56 |
Current CPC
Class: |
D01F 1/04 20130101; A41G
3/0083 20130101; D01F 6/62 20130101 |
Class at
Publication: |
132/201 ; 132/56;
132/53 |
International
Class: |
A41G 3/00 20060101
A41G003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2006 |
JP |
2006-021539 |
Claims
1. An artificial hair, characterized in that: it is made of a fiber
including polyethylene terephthalate, and has bending rigidity
similar to that of natural hair.
2. An artificial hair, characterized in that: it is made of a fiber
including polyethylene terephthalate, and has bending rigidity
similar to that of natural hair by having a cross-sectional size
similar to that of natural hair.
3. The artificial hair as set forth in claim 1 or 2, characterized
in that: it has a cross-sectional size perpendicular to the length
direction of said fiber in the range of 50 to 70 .mu.m as an
average diameter.
4. An artificial hair, characterized in that: it is made of a fiber
including polyethylene terephthalate and polybutylene
terephthalate, and has bending rigidity similar to that of natural
hair.
5. The artificial hair as set forth in claim 4, characterized in
that: it has a cross-sectional size perpendicular to the length
direction of said fiber in the range of 50 to 100 .mu.m as an
average diameter.
6. The artificial hair as set forth in claim 1, 2, or 4,
characterized in that: said fiber has bending rigidity in the range
of 6.5 to 7.8.times.10.sup.-3 gfcm.sup.2/strand at 40%
humidity.
7. The artificial hair as set forth in claim 1, 2, or 4,
characterized in that: fine pores are formed in the length
direction on the surface of said fiber.
8. An artificial hair bundle, characterized in that: it is made up
to a bundle by dispersing a first artificial hair made of a
polyester resin in a second artificial hair made of a polyamide
resin in the pre-determined ratio, said polyester resin includes
polyethylene terephthalate, and said first artificial hair has a
cross-sectional size and bending rigidity similar to those of
natural hair.
9. An artificial hair bundle, characterized in that: it is made up
to a bundle by dispersing a first artificial hair made of a
polyester resin in a second artificial hair made of a polyamide
resin in the pre-determined ratio, said polyester resin includes
polyethylene terephthalate and polybutylene terephthalate, and said
first artificial hair has bending rigidity similar to that of
natural hair.
10. The artificial hair bundle as set forth in claim 8 or 9,
characterized in that: said second artificial hair has a
sheath/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 of the bending rigidity lower than that of said core
portion.
11. The artificial hair bundle as set forth in claim 8 or 9,
characterized in that: said second artificial hair has a
cross-sectional size and bending rigidity similar to those of
natural hair.
12. The artificial hair bundle as set forth in claim 8 or 9,
characterized in that: said bending rigidity is in the range of 6.5
to 7.8.times.10.sup.-3 gfcm.sup.2/strand at 40% humidity.
13. The artificial hair bundle as set forth in claim 8 or 9,
characterized in that: the cross-sectional size perpendicular to
the length direction of said first artificial hair is in the range
of 50 to 70 .mu.m as an average diameter.
14. A wig comprising a wig base and artificial hair attached to
said wig base, characterized in that: a first artificial hair made
of a polyester resin and a second artificial hair made of a
polyamide resin are used as said artificial hair, said polyester
resin includes polyethylene terephthalate, and said first
artificial hair has bending rigidity similar to that of natural
hair by having a cross-sectional size similar to that of natural
hair.
15. A wig comprising a wig base and artificial hair attached to
said wig base, characterized in that: a first artificial hair made
of a polyester resin and a second artificial hair made of a
polyamide resin are used as said artificial hair, said polyester
resin includes polyethylene terephthalate and polybutylene
terephthalate, and said first artificial hair has bending rigidity
similar to that of natural hair.
16. The wig as set forth in claim 14 or 15, characterized in that:
said second artificial hair has a sheath/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 of the bending rigidity lower
than that of said core portion.
17. A method of making artificial hair having a cross-sectional
size and bending rigidity similar to those of natural hair,
characterized in that: said method is comprises of a first step to
add a coloring material to the polyethylene terephthalate as a
starting material, and to melt and discharge, a second step to
solidify the discharged fiber-shaped melt, and a third step to
stretch the solidified fiber-shaped material to the pre-determined
diameter.
18. A method of making artificial hair having bending rigidity
similar to that of natural hair, characterized in that: said method
is comprised of a first step to melt and discharge the polyethylene
terephthalate and polybutylene terephthalate as starting materials
and a coloring material in the pre-determined mass ratio, a second
step to solidify the discharged fiber-shaped melt, and a third step
to stretch the solidified fiber-shaped material to the
pre-determined diameter.
19. The method of making artificial hair as set forth in claim 17
or 18, characterized in that: in either of said second or third
step, fine pores are formed on the surface of artificial hair by an
alkali denier reduction treatment.
Description
TECHNICAL FIELD
[0001] This invention relates to artificial hair having feeling and
physical properties similar to those of natural hair, a wig using
the same attached thereto, and a method of making the artificial
hair.
BACKGROUND ART
[0002] Natural hair in general has a diameter of about 80 to 100
.mu.m, and is curled naturally or by a permanent wave treatment,
but has a characteristic property that the curl is deformed and
stretched when wetted by exposure to the rain or washing. Also, it
is known that such as moist and tactile feelings, or such physical
properties as bending rigidity are changed by the change of
humidity. Therefore, natural hair obtained from humans and animals
has long been prepared and used fondly as a material so as to have
the characteristics as much as possible similar to that of human
hair. However, for the reason of restricted supply of natural hair
material or others, synthetic fibers have recently been often
manufactured as a hair material for a wig. For example,
polyacrylic, polyester, or polyamide synthetic fibers are used in
many cases as a material of artificial hair.
[0003] The artificial hair of an acrylic fiber has low melting
point and poor heat stability, so that it has such weak points as
poor shape preservation after permanent wave setting, resulting in
deformation of setting, for example, such as curl on fibers and the
like when exposed to warm water. It also differs from natural hair
in moist and tactile feelings and since it lacks toughness,
uncomfortable feeling is neither denied.
[0004] On the other hand, polyester fibers excel in strength and
heat stability, but have extremely low moisture absorbency compared
with natural hair, and they show appearance, tactile feeling, and
physical properties different from those of natural hair under high
humidity, resulting in uncomfortable feeling when used as hair for
a wig. When natural hair gets wet in the rain or exposed to
moisture upon hair washing, curl is deformed and stretched, whereas
polyester fibers have extremely weak moisture absorbency and
retention, so that show the feature of rich curl retention,
resulting in almost no stretching. Therefore, if artificial hair is
made of polyester fibers, and is curling-treated, the given curl
does not tend to be deformed under high humidity, resulting in
remarkably unnatural feeling different from the behavior of natural
hair. Thus, polyester fibers can not show the behavior like natural
hair that such as moist and tactile feelings and such physical
properties as curl retention change with humidity change.
[0005] In addition, the polyester fiber of same diameter as that of
natural hair of about 80 to 100 .mu.m has too high bending rigidity
compared with natural hair. The bending rigidity is the property
relating to such feeling as tactile and texture of fibers, the
required force for bending, 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 bending
rigidity using a single strand of fiber or hair (See Non-Patent
Reference 2.). Said 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 bending rigidity of artificial
hair, the less bendable, the more resistant to bending, that is,
the harder and the less bendable is artificial hair. Conversely,
the smaller the bending rigidity, the more bendable and the softer
is artificial hair.
[0006] Since bending rigidity of the hair made of polyester having
the same diameter as that of natural hair, about 80 to 100 .mu.m,
is extremely high compared with natural hair, if it is attached to
a wig base, it stands upward too much. The hair of polyester feels
rough, is high in tough feeling compared with natural hair, and
moderate ductility can not be shown as with natural hair. For a
so-called wearer's own hair-utilized wig which is worn by mixing
the wearer's own hair and the wig hair, when polyester hair is used
for a wig, the hair of polyester fiber does not adapt to the
wearer's own soft hair, and stands up fuzzy among the moderately
lying wearer's own hairs. Such tendency of separation of the
wearer's own hair and the hair of polyester becomes more remarkable
with higher humidity.
[0007] On the other hand, polyamide fibers have appearance and
physical properties similar to those of natural hair in many
aspects, and excellent wigs have been provided, especially by the
invention of the present applicant which removes unnatural gloss by
surface treatment. (See Patent Reference 1.). Among polyamide
fibers, aliphatic polyamide is especially preferable as artificial
hair owing to its excellent processability. However, the fiber made
of aliphatic polyamide has low bending rigidity compared with
natural hair, so that its standing up is inferior when attached to
a wig base, and it lies down along the wig base. Consequently, the
artificial hair made of aliphatic polyamide is poor in tough
feeling, and tends to be inferior in bulky feeling. As the result
of the present applicant's strenuous study, with a double structure
of sheath and core of an aliphatic and an aromatic polyamide
resins, respectively, artificial hair was successfully manufactured
which shows quite similar behavior to that of natural hair changing
with the humidity change. (Japanese Patent Application. 2005-38415,
Feb. 15, 2005). By this art, the hair of polyamide fiber can attain
bending rigidity similar to that of natural hair.
[0008] As other arts regarding artificial hair, such arts are
proposed that preparing an artificial hair bundle by mixing
polyester fibers and nylon fibers and attaching to a wig several
strands pulled out of said artificial hair bundle so that a hair
dryer or a curling iron can be used (Patent Reference 2) and
maintaining moisture retention and approximating tint and gloss as
a whole to natural hair by mixing natural hair to the artificial
hair made of polyester fibers (Patent Reference 3). Patent
Reference 4 discloses a bristle material for brushes such as tooth
brushes and face brushes having moderate toughness by mixing and
melt-spinning polyethylene terephthalate to polybutylene
terephthalate. Patent Reference 5 discloses short fibers made of a
blend polymer containing polyethylene terephthalate and
polybutylene terephthalate to attain soft tactile feeling as a car
seat surface material for transportation vehicles and a vehicular
interior material such as a door interior material. Patent
Reference 6 discloses a false-twist textured thread made by
blending polyethylene terephthalate to polybutylene terephthalate
to provide a soft textile excellent in stretchability. Patent
Reference 7 discloses a non-woven textile made of polyethylene
terephthalate and polybutylene terephthalate mixed in the
pre-determined mass ratio.
[0009] [Patent Reference 1] Japan Patent Laid Open S64-6114 A
(1989)
[0010] [Patent Reference 2] Japan Patent Laid Open H9-324314 A
(1997)
[0011] [Patent Reference 3] Japan Utility Model Registration
3021160
[0012] [Patent Reference 4] Japan Patent Laid Open 2004-166966
A
[0013] [Patent Reference 5] Japan Patent Laid Open 2004-84119 A
[0014] [Patent Reference 6] Japan Patent Laid Open 2000-273727
A
[0015] [Patent Reference 7] Japan Patent 345824
[0016] [Non-Patent Reference 1] Sen'ikikai Gakkaishi (Journal of
Textile Machine Society, Textile Engineering), Sueo KAWABATA, 26,
10, pp. 721-728, 1973
[0017] [Non-Patent Reference 2] KATOTECH LTD., Handling Manual of
KES-SH Single Hair Bending Tester
DISCLOSURE OF THE INVENTION
Problems to be Solved
[0018] As described above, artificial hair to be used for wigs is
made variously so as to have feeling (appearance, tactile and
texture) as close as possible to that of natural hair, and such
physical properties as moisture absorbency, tensile strength,
elasticity, and bending rigidity are required not inferior to, or
preferably, superior to those of natural hair. Since the present
applicant's artificial hair made of above-mentioned polyamide fiber
has a diameter of about 80 to 100 .mu.m which is about same as that
of natural hair as mentioned above, and can provide feeling quite
close to natural hair, it is a quite excellent material. However,
when the artificial hairs made of polyamide fibers are attached to
a wig base, they have a tendency to stick together to be bundled as
a plurality of strands as time elapses. Therefore, the bundled
hairs have to be combed each time carefully so that they are
disintegrated. Also, since the artificial hair of a polyamide fiber
has moisture absorbency like natural hair, fibers tend to stick
together to be bundled due to their property at high humidity. This
tendency is more noticeable at higher humidity. Therefore, when
artificial hairs of polyamide are bundled by absorbing moisture,
for example upon wetting in the rain or hair-washing, a wig wearer
has such a problem that combing, brushing and hair-styling of the
bundled hairs would not be disintegrated each strand, and hence it
takes time to set a desired hairstyle. This property is same for
the artificial hair of a sheath/core double structure of the
above-mentioned aliphatic and aromatic polyamide resins, and it is
difficult to prevent bundling of the artificial hairs of polyamide
fibers, and since artificial hairs are adhered tightly at higher
humidity, it is also difficult to prevent them from bundling.
[0019] If the artificial hairs of mixed polyester fibers and nylon
fibers are attached to a wig base, as described in Patent reference
2, bundling of nylon fibers can be prevented, but nylon fibers lie
down on the wig base like natural hair, whereas the artificial
hairs of polyester fibers stand up, and hence do not blend well
with natural hair and nylon fibers, resulting in appearance of
separation. This tendency is more noticeable at higher humidity,
and nylon fibers lie down due to their moisture absorbency in high
humidity to be stuck to a scalp like natural hair, whereas since
polyester fibers have high bending rigidity and low moisture
absorbency, they keep the state of standing up, and hence the wig
wearing can not show natural appearance and is easily visible.
[0020] An object of the present invention is, in view of the
above-mentioned problems, to provide an artificial hair having
feeling and physical properties similar to those of natural hair,
especially a part of the artificial hair attached to a wig base
does not stand up in unnatural manner, excellent in hair shape
retention, the same curling property as human hair can be realized,
the artificial hairs are not bundled mutually under the influence
of humidity giving flow feeling, and in addition, it has bending
rigidity similar to that of natural hair, showing the behavior
similar to natural hair, a wig using the above-mentioned artificial
fair and a method of making the same.
Means to Solve Problems
[0021] As the result of the present inventors' strenuous study,
knowledge was obtained that, on the assumption of the state of
polyamide artificial hair bundle being bundled due to the molecular
structure of polyamide artificial hair, or due to the molecular
bonding on the surfaces of polyamide artificial hair, so-called Van
der Waals force, various experiments were performed to turn out
that the state of bundling can be solved by not a single polyamide
artificial hair but by mixing other synthetic fibers, more
concretely, the artificial hair containing polyethylene
terephthalate. Further, in order for polyamide artificial hair to
have bending rigidity similar to that of natural hair, quite
excellent property can be obtained by making the fiber having a
double structure of a sheath and a core and by adjusting the
sheath/core ratio and others. In case of polyethylene terephthalate
artificial hair, the present invention was completed by obtaining
the knowledge that it is attained by either controlling its
diameter, or by melt-spinning with other synthetic resins.
[0022] In order to achieve the above-mentioned object, an
artificial hair of the present invention is the fiber containing
polyethylene terephthalate, having bending rigidity similar to that
of natural hair. More concretely, said artificial hair is made of
the fiber containing polyethylene terephthalate, having bending
rigidity similar to that of natural hair by making the
cross-sectional size similar to that of natural hair, for example,
that perpendicular to the length direction of fiber in the range of
50 to 70 .mu.m as an average diameter.
[0023] Said artificial hair is preferably the fiber containing
polyethylene terephthalate and polybutylene terephthalate, having
bending rigidity similar to that of natural hair. In this case, the
cross-sectional size perpendicular to the length direction of fiber
may be in the range of 50 to 100 .mu.m as an average diameter
[0024] In the above-mentioned constitutions, bending rigidity of a
fiber is preferably in the range of 6.5 to 7.8.times.10.sup.-3
gfcm.sup.2/strand at humidity 40%. On the surface of the fiber,
fine pores are preferably formed in the length direction.
[0025] In the above-mentioned constitutions, the artificial hair of
bending rigidity similar to that of natural hair can be provided by
making the cross-sectional size of a fiber made of polyethylene
terephthalate similar to that of natural hair. Since also bending
rigidity can be spontaneously adjusted with polyethylene
terephthalate of high bending rigidity and polybutylene
terephthalate of low bending rigidity, resulting in the bending
rigidity similar to that of natural hair, artificial hair similar
to natural hair can be provided. Consequently, since these
artificial hairs have bending rigidity similar to that of natural
hair, natural artificial hair can be provided which has such
feeling as appearance, tactile and texture feelings especially
quite similar to those of natural hair. Since standing up of this
artificial hair from a wig base shows the behavior similar to the
standing up of natural hair from a scalp, natural feeling is
realized, and wearing a wig is not visible. By forming fine pores
in the length direction on the surface of artificial hair, the
irradiated light is diffusely reflected to suppress gloss, giving
the gloss similar to that of natural hair.
[0026] Artificial hair bundle of the present invention is
characterized in that it is made up to a bundle by dispersing a
first artificial hair made of a polyester resin in a second
artificial hair made of a polyamide resin in the pre-determined
ratio, further said polyester resin includes polyethylene
terephthalate, and the first artificial hair has a cross-sectional
size and bending rigidity similar to those of natural hair.
[0027] In said first artificial hair, polyester resin preferably
includes polyethylene terephthalate and polybutylene terephthalate,
and has bending rigidity similar to that of natural hair. The
cross-sectional size perpendicular to the length direction of said
first artificial hair is in the range of 50 to 70 .mu.m as an
average diameter. Said second artificial hair preferably has a
sheath/core structure made of a core portion and a sheath portion
covering said core portion, the core portion is made of a polyamide
resin, and the sheath portion is made of a polyamide resin of
bending rigidity lower than that of said core portion. The second
artificial hair preferably has a cross-sectional size and bending
rigidity similar to those of natural hair, which is in the range of
6.5 to 7.8.times.10.sup.-3 gfcm.sup.2/strand at humidity 40%.
[0028] By properly mixing the first artificial hair made of
polyester resin to said second artificial hair made of polyamide
resin, and by attaching them to a wig base in a proper dispersing
state, bundling of the second artificial hair itself can be
suppressed. Since the first artificial hair has a material of
polyethylene terephthalate and polybutylene terephthalate, it has
bending rigidity similar to natural hair compared with the material
of only polyethylene terephthalate, and natural artificial hair the
feelings such as appearance, tactile and texture of which are quite
close to those of natural hair can be provided.
[0029] A wig of a first constitution of the present invention
comprises a wig base and artificial hair attached to said wig base,
characterized in that a first artificial hair made of a polyester
resin and a second artificial hair made of a polyamide resin are
used as said artificial hair, said polyester resin includes
polyethylene terephthalate, and said first artificial hair has
bending rigidity similar to that of natural hair by having a
cross-sectional size similar to that of natural hair.
[0030] A wig of a second constitution of the present invention
comprises a wig base and artificial hair attached to said wig base,
characterized in that a first artificial hair made of a polyester
resin and a second artificial hair made of a polyamide resin are
used as said artificial hair, said polyester resin includes
polyethylene terephthalate and polybutylene terephthalate, and said
first artificial hair has bending rigidity similar to that of
natural hair. The second artificial hair preferably has a
sheath/core structure comprising a core portion and a sheath
portion covering the core portion, the core portion is made of a
polyamide resin, and the sheath portion is made of a polyamide
resin of bending rigidity lower than that of the core portion.
[0031] By using artificial hair of the above-mentioned constitution
for a wig of the present invention, a wig can be provided which
gives natural flow feeling, and shows behavior similar to that of
natural hair. Therefore, since the first artificial hair made of a
polyester resin is attached by properly mixing with the second
artificial hair made of a polyamide resin, bundling of the second
artificial hair is suppressed, hair style setting causes no trouble
regardless of high or low humidity, the wig-wearing is not visible
owing to the appearance as if it were the wearer's own hair growing
naturally from a scalp.
[0032] A first constitution of a method of making artificial hair
is characterized in that, in order to obtain artificial hair having
a cross-sectional size and bending rigidity similar to natural
hair, said method is comprised of a first step to add a coloring
material to the polyethylene terephthalate as a starting material,
and to melt and discharge, a second step to solidify the discharged
fiber-shaped melt, and a third step to stretch the solidified
fiber-shaped material to the pre-determined diameter. A second
constitution is characterized in that, in order to obtain
artificial hair having bending rigidity similar to those of natural
hair, said method is comprised of a first step to melt and
discharge the polyethylene terephthalate and polybutylene
terephthalate as starting materials and a coloring material in the
pre-determined mass ratio, a second step to solidify the discharged
fiber-shaped melt, and a third step to stretch the solidified
fiber-shaped material to the pre-determined diameter. In said first
and second constitutions, fine pores may be formed on the surface
of artificial hair by an alkali denier reduction treatment in
either of the second or third step.
[0033] In accordance with the above-mentioned constitutions,
artificial hair made of a polyester resin can be provided which has
properties similar to those of natural hair, and further,
artificial hair can be provided which suppresses bundling of
artificial hair made of a polyamide resin by mixing the artificial
hair made of a polyester resin in artificial hair made of a
polyamide resin.
EFFECT OF THE INVENTION
[0034] According to the present invention, the artificial hair of a
polyester resin can be provided which has feeling (appearance,
tactile and texture) and physical properties, especially bending
rigidity similar to that of natural hair. Since said artificial
hair suppresses bundling of the artificial hairs of a polyamide
resin, the artificial hairs of a polyamide resin are no longer
bundled and disintegrated to each strand by using and mixing proper
number of strands as hair in the wig having the artificial hairs of
a polyamide resin attached thereto. Therefore, this artificial hair
puts artificial hair of a polyamide resin into the smooth state,
and can show the similar behavior to natural hair. Therefore, by
the wig of the present invention, since the hair attached to the
wig shows the similar behavior to the wig wearer's own hair, the
wig wearing is hardly visible, and provides excellent
appearance.
[0035] Since conventional artificial hair of a polyester resin has
higher bending rigidity than that of natural hair, it stands up
markedly from a wig base, and together with the low bending
rigidity of artificial hair of a polyamide resin attached to the
same wig base, the artificial hair of a polyester resin stands up
and is markedly distinguished, the wig wearing is highly visible,
and uniformity as a hair style can not be attained. On the other
hand, if artificial hair of a polyester resin attached to a wig
base has bending rigidity lower than that of natural hair, it is in
the state as if lying down along the wig base. Therefore, the stand
up of artificial hair of a polyamide resin of bending rigidity
similar to that of natural hair is highly visible, and since the
standing and the lying hairs are mixed, the wig wearing is easily
visible, and uniformity as a hair style can not be attained. On the
other hand, since said artificial hair of a polyester resin
according to the present invention has bending rigidity similar to
that of natural hair, it stands up similar to that of artificial
hair of a polyamide resin attached to a wig base, and the wig
wearing is hardly visible.
BRIEF DESCRIPTION OF THE DRAWINGS
[0036] FIG. 1 is a view illustrating an embodiment of artificial
hair in accordance with the present invention.
[0037] FIG. 2 is a cross-sectional view in the length direction
illustrating another embodiment of artificial hair in accordance
with the present invention.
[0038] FIG. 3 is a view illustrating an artificial hair bundle of
the present invention.
[0039] FIG. 4 diagramatically illustrates a preferable make up of a
second artificial hair shown in FIG. 3, in which (A) is a diagonal
view, and (B) is a cross-sectional view in the length direction of
the second artificial hair.
[0040] FIG. 5 is a cross-sectional view in the length direction
diagrammatically illustrating a modified version of the second
artificial hair.
[0041] FIG. 6 is a diagonal view diagrammatically illustrating a
make up of the second artificial hair.
[0042] FIG. 7 is a view diagrammatically illustrating,
respectively, (A) a wig of the present invention, and (B) a wig of
a Comparative Example.
[0043] FIG. 8 is a diagrammatical view illustrating a series of
apparatuses used for manufacturing artificial hair of the present
invention.
[0044] FIG. 9 is a view diagrammatically illustrating an alkali
denier reducing part.
[0045] FIG. 10 is a diagrammatical view illustrating a
manufacturing apparatus used for manufacturing the second
artificial hair making up the artificial hair bundle of the present
invention.
[0046] FIG. 11 is a diagrammatical view illustrating a discharging
part used for the manufacturing apparatus of FIG. 10.
[0047] FIG. 12 is a view showing a scanning electron microscopic
image of the artificial hair manufactured in Example 1.
[0048] FIG. 13 is a graph showing the relationship of bending
rigidity with regard to the cross-sectional diameter of artificial
hair manufactured in Examples 1 to 5 and Comparative Examples 1 to
3.
[0049] FIG. 14 is a graph showing the bending rigidity with regard
to the mixing ratio of polybutylene terephthalate mass.
[0050] FIG. 15 is a graph showing the bending rigidity before and
after the alkali denier reducing process in case of 20% and 60% of
the mixing ratio of polybutylene terephthalate.
[0051] FIG. 16 is a graph showing thermal shrinkage ratio with
regard to bending rigidity of each artificial hair.
TABLE-US-00001 [0052] Explanation of Marks and Symbols 1, 2: First
artificial hair 2a: Fine pore 5, 6: Second artificial hair 5A:
Sheath portion 5B: Core portion 5C: Concave and convex portion 10:
Artificial hair bundle 20: Wig 21: Wig base 30, 50: Manufacturing
apparatus 31, 51, 52: Feed material tank 31A, 51A, 52A: Melt liquid
32, 51D, 52D: Melt extruder 32A, 53C: Outlet 33, 54: Quenching bath
34, 36, 38, 40, 55, 57, 59, 62: stretching roll 35, 37, 39, 56, 58,
60: Dry stretching bath 41, 64: Rollup machine 45: Alkali denier
reducing part 46: Liquid storage part 47: Rotating cylinder 47a:
Jet nozzle 48: Shower part 51B, 52B: Gear pump 53: Discharging part
53A: Outer ring part 53B: Inner circle part 61: Oiling device for
electrostatic prevention 62: Blast machine 100: Fiber
BEST MODES FOR CARRYING OUT THE INVENTION
[0053] Hereinafter, the present invention is explained in details
with reference to the embodiments illustrated in the figures.
[0054] Explanation is first made of an artificial hair. The
artificial hair of the present invention is made of a polyester
synthetic fiber, and has bending rigidity similar to that of
natural hair. Here, polyethylene terephthalate is a polymer
practically obtained by condensation polymerization of terephthalic
acid and ethylene glycol. Bending rigidity similar to that of
natural hair is optimally 6.5 to 7.8.times.10.sup.-3
gfcm.sup.2/strand at humidity 40%, and 3.9 to 5.8.times.10.sup.-3
gfcm.sup.2/strand at humidity 80%. When the artificial hair of
polyester artificial fibers are dispersed in the artificial hair
made of polyamide synthetic fibers and attached to a wig base in
the pre-determined ratio, then bundling of the artificial hair made
of polyamide synthetic fibers is suppressed, and since the
artificial hair of polyester fibers has bending rigidity similar to
those of the artificial hair of polyamide fibers and natural hair,
it shows similar behavior to the natural hair growing from the wig
wearer's scalp and the artificial hair of polyamide fibers attached
to the wig base, for example, it has the similar growing state
similar to that of the polyamide artificial hair attached to the
wig base and the natural hair growing from the wig wearer's scalp,
resulting in uniform appearance.
[0055] Hereinafter, explanation is made of each embodiment of
artificial hair of the present invention.
[0056] A first embodiment of artificial hair of the present
invention is the fiber with polyethylene terephthalate as the
component containing coloring pigments whenever necessary, and has
bending rigidity similar to that of natural hair by having a
cross-sectional size similar to that of the artificial hair.
[0057] FIG. 1 is view illustrating an embodiment of the artificial
hair with polyethylene terephthalate as the component of the
present invention. Said artificial hair 1 may have the cross
section of either an exact circle shown in FIG. 1, or an ellipsoid
compressed in any direction or cocoon shape. The artificial hair 1
in accordance with the first embodiment of the present invention
has the average cross-sectional diameter of 50 to 70 .mu.m. If the
average diameter of the cross section of artificial hair 1 is less
than 50 .mu.m, then its bending rigidity is lower than that of
natural hair, and it is undesirable that it lies along a wig base
when attached thereto. On the other hand, if the average diameter
exceeds 70 .mu.m, then its bending rigidity is much higher than
that of natural hair, and it is undesirable that its standing up is
too much from a wig base when attached thereto.
[0058] A second embodiment of artificial hair of the present
invention is the synthetic fiber of polyester, and, by containing
polyethylene terephthalate and polybutylene terephthalate in the
pre-determined ratio as the components of said synthetic fiber of
polyester, it has bending rigidity similar to that of natural hair.
Polybutylene terephthalate is a polymer practically obtained by
condensation polymerization of terephthalic acid and 1,4-butane
diol. The artificial hair of said second embodiment may have the
cross section of either an exact circle as in FIG. 1, or an
ellipsoid compressed in any direction or cocoon shape. Its
cross-sectional size is preferably 50 to 100 .mu.m. With said
artificial hair, it is convenient that the diameter can be same 80
to 100 .mu.m as natural hair.
[0059] Explanation is made of a third embodiment of artificial
hair.
[0060] FIG. 2 is a cross-sectional view in the length direction
illustrating artificial hair 2 in accordance with the third
embodiment of the present invention. Unlike FIG. 1, fine concave
and convex portion 2a is formed on the surface of said artificial
hair 2. As for the artificial hair 2 having such a concave and
convex portion 2a, since diffuse reflection is caused when light is
irradiated, gloss due to the reflection by light irradiation is
hardly caused on the surface of artificial hair 2, thereby
so-called deglossing effect can be realized. The concave and convex
portion 2a is preferably formed to be larger than the order of
visible light wavelength so that light is reflected diffusively.
Said concave and convex portion 2a can be formed by, for example,
after spinning the artificial hair, soaking for weight reducing
processing in sodium hydroxide solution or others, and
water-washing and drying, but it may also be formed by conducting
blast treatment. The components of artificial hair 2 may be
composed with polyethylene terephthalate as in the first
embodiment, or may be polyethylene terephthalate and polybutylene
terephthalate mixed in the pre-determined ratio as in the second
embodiment. The artificial hair of the above-mentioned embodiments
may contain pigments as components for the pre-determined
coloring.
[0061] The fiber made of polyethylene terephthalate in general has
strong bending rigidity, so that it has so far been not proper as a
material of artificial hair, but with artificial hair 1, 2 of the
present invention, if the fiber has a cross-sectional size similar
to, or a little smaller than that of natural hair, bending rigidity
is close to that of natural hair, and appearance and tactile and
texture feelings can be attained similar to those of natural hair.
Also with the fiber made of polyethylene terephthalate and
polybutylene terephthalate, bending rigidity is close to that of
natural hair with practically similar diameter to that of natural
hair, and appearance and tactile and texture feelings can be
attained similar to those of natural hair. By attaching to a wig
base artificial hair of said first to third embodiments
(hereinafter referred to as "first artificial hair") and a
plurality of a second artificial hair made of polyamide fiber so
that they are mixed, each strand of the first and the second
artificial hairs is unbundled to make them smooth. Thereby bundling
of the second artificial hair can be suppressed. When made to the
desired hairstyle, unnaturalness by bundling can be prevented, and
natural appearance can be provided to a wig.
[0062] Explanation is made hereafter of artificial hair bundle 10
of the present invention.
[0063] FIG. 3 is a view diagrammatically illustrating an artificial
hair bundle 10 of the present invention. The artificial hair bundle
10 is so constituted that, as shown in FIG. 3, the pre-determined
number of strands of the first artificial hair 1 made of polyester
synthetic fiber are dispersed and blended in a plurality of the
second artificial hair 5 made of polyamide synthetic fiber to form
a bundle, and said first and second artificial hairs are properly
dispersed in a wig base to be randomly attached. The polyamide
synthetic fiber as the second artificial hair 5 has a
cross-sectional size and bending rigidity similar to those of
natural hair.
[0064] For said artificial hair bundle 10, the thermal shrinkage
ratio of the second artificial hair 5 is preferably about same as
or lower than that of the first artificial hair 1. Thereby, since
the first artificial hair 1 and the second artificial hair 5 shrink
to about same extent when curling treatment by heat is applied to
the artificial hair bundle 10, wavy steps can be prevented from
generating. The cause of wavy step generation is as described
below. If the thermal shrinkage ratio of the second artificial hair
5 is higher than that of the first artificial hair 1, when curling
treatment by heat is applied to the artificial hair bundle 10, the
first artificial hair 1 neighboring the second artificial hair 5
tends to shrink as does the second artificial hair 5. However, the
shrinkage of the second artificial hair 5 is larger than that of
the first artificial hair 1, and hence the first artificial hair 1
of small shrinkage is pulled to cause kinks and slacks, and the
pre-determined good curling can be no longer given, thereby wavy
steps appear.
[0065] FIG. 4 is a view diagrammatically illustrating the preferred
makeup of a second artificial hair 5 shown in FIG. 3, in which (A)
is a diagonal view, and (B) is a vertical cross sectional view in
the length direction of the second artificial hair 5. As is
illustrated, the second artificial hair 5 has a sheath/core
structure wherein its surface is a sheath portion 5A, and a core
portion 5B is inside the sheath portion 5A, both portions made of a
polyamide resin. In 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 5B and sheath 5A have different shapes other than nearly
concentric circles, or the cross sectional shape of the second
artificial hair 5 may be circular, elliptic, or cocoon-shaped.
[0066] As the polyamide resins for the material of said core
portion 5B, semi-aromatic polyamide resins of high strength and
bending rigidity can be properly used. As said semi-aromatic
polyamide, such may be mentioned as the polymer consisting of an
alternate 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 bound by amide bond (Nylon MXD6, for example) expressed
in Chemical Formula 2. The polymer material expressed in Chemical
Formula 2 has a merit in easier hairset than that expressed in
Chemical Formula 1.
##STR00001##
[0067] As the polyamide resins for the material of said sheath
portion 5A, polyamide resins of lower bending rigidity than the
core 5B 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, for example
Nylon 6, expressed in Chemical Formula 3, or the polymer consisting
of an alternate copolymer of hexamethylenediamine and adipic acid,
for example Nylon 66, expressed in Chemical Formula 4.
##STR00002##
[0068] The second artificial hair 5 has gloss, if the surface of
the sheath 6A is smooth. In order to erase this unnatural gloss on
the surface of the second artificial hair 5, so-called deglossing
may be preferably applied. FIG. 5 is a cross sectional view in the
length direction diagrammatically illustrating the makeup of a
modified example of the second artificial hair 6. As is
illustrated, on the surface of the sheath portion 6A of the second
artificial hair 6, a fine concave and convex portion 5C is
formed.
[0069] Here, the fine concave and convex portion 5C can be given by
blast processing with fine powder such as sand, ice, dry-ice, and
others either during spinning of the second artificial hair 6 or on
to the fiber after spinning. In case during spinning of the second
artificial hair 6, it may be by spherulite formation on the
outermost surface of the second artificial hair 6. It may be the
combined processes of spherulite formation and blast processing
with fine powder such as said sand, ice, dry-ice, and others. The
concave and convex portion formed by such spherulite formation
and/or blast processing may be formed to be the concave and convex
portion 5C larger than the order of visible light wavelength so the
light is diffuse reflected. The second artificial hair 5, 6 can be
dyed in general 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 after spinning. By making a
sheath/core structure with the polyamide of high bending rigidity
used for the core 5B, and with the polyamide of the bending
rigidity lower than the core 5B used for the sheath 6A, the second
artificial hair 5, 6 can be obtained the rigidity of which is
changed by temperature and humidity, and which shows behavior
closer to the natural hair.
[0070] The mixing ratio of the first artificial hair 1, 2 and the
second artificial hair 5, 6 in an artificial hair bundle 10 is
preferably in the range of 10 to 60 weight %, and more preferably
about 20 to 30 weight %. In this preferred range, polyamide fibers
do not bundle. It is not preferable that, if the mixing ratio of
the first artificial hair 1, 2, that is, a polyester fiber is lower
than 10 weight %, then polyamide fibers bundle. On the other hand,
if the mixing ratio of polyester fibers (the first artificial hair)
exceeds 60 weight %, then, though the polyamide fibers do not
bundle, the polyester fibers (the first artificial hair) are not
preferably too much visible. Since polyester fibers have lower
moisture absorbency than polyamide fibers, the artificial hair
bundle 10 made of two kinds of fibers shows a different behavior by
humidity change due to the difference in moisture absorbency.
[0071] Thus, the reason why bundling hardly occurs when a polyester
artificial hair is mixed in a polyamide artificial hair is assumed
that a polyester artificial hair of a different chemical structure
is mixed in a polyamide artificial hair, and that a polyamide
artificial hair tends to be electrically charged positively, while
a polyester artificial hair tends to be charged negatively.
[0072] With the first artificial hair 1, 2 and the second
artificial hair 5, 6 are mixed in a preferable weight ratio in an
artificial hair bundle 10, the second artificial hair 5, 6 does not
bundle, and the first artificial hair 1, 2 and the second
artificial hair 5, 6 can have bending rigidity similar to that of
natural hair.
[0073] Explanation is next made of a wig of the present
invention.
[0074] FIG. 6 is a diagonal view diagrammatically illustrating the
structure of a wig 20 of the present invention. A wig 20 using the
artificial hair 1, 2 of the present invention is made by attaching
the first artificial hair 1, 2 and the second artificial hair 5, 6
in the pre-determined ratio to a wig base 11. The first artificial
hair 1, 2 is made of a polyester synthetic fiber as mentioned
above, having bending rigidity similar to that of natural hair. The
second artificial hair 5, 6 is made of a polyamide synthetic fiber,
having a cross-sectional size and bending rigidity similar to those
of natural hair, and preferably comprises, as mentioned above, a
core portion 5B of a high bending rigidity polyamide resin and a
sheath portion 6A of a polyamide resin having lower bending
rigidity than the core portion 5B.
[0075] The mixing ratio of the first artificial hair 1, 2 and the
second artificial hair 5, 6 attached to a wig base 21 is preferably
that the first artificial hair 1, 2 is about 20.+-.5 weight % in an
arbitrary region, because the second artificial hairs 5, 6 made of
a polyamide fiber attached to the wig base 21 does not bundle in
this preferred range. It is not preferable that, if the mixing
ratio of the first artificial hair is less than 20.+-.5 weight %,
then polyamide fibers bundle. On the other hand, if the mixing
ratio of polyester fibers (the first artificial hair) exceeds
20.+-.5 weight %, then, though the polyamide fibers do not bundle,
the polyester fibers (the first artificial hair) are not preferably
too much visible.
[0076] The wig base 21 can be made of either a net-like base or an
artificial skin base. In case of the figure, the wig base 21 is
made of a net member, and the first artificial hair 1, 2 and the
second artificial hair 5, 6 are tied to a mesh of the net member.
The wig base 21 may be made by combination of a net-like base and
an artificial skin base, and there is no special restriction so far
as suitable to wig design or purpose of use.
[0077] The first artificial hair 1, 2 and the second artificial
hair 5, 6 are preferably the artificial hair respectively having
gloss similar to that of natural hair, with their surface specular
glossiness suppressed. The colors of the first and the second
artificial hair 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 lost hair portion. In case of a
wig or hair extension 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.
[0078] FIGS. 7(A) and (B) are views diagrammatically illustrating,
respectively, a wig 20 of the present invention, and a wig 25 as a
Comparative Example. As shown in FIG. 7(A), in the wig 20 of the
present invention, since the first artificial hair 1, 2 is so made
as to have bending rigidity similar to that of the second
artificial hair 5, 6 having bending rigidity similar to that of
natural hair, the first artificial hair 1, 2 and the second
artificial hair 5, 6 look similar, and are not distinguishable
strictly when attached to a wig base 21. Further, an excellent wig
can be provided wherein the polyamide fibers constituting the
second artificial hair 5, 6 do not bundle. On the other hand, as
shown in FIG. 7(B), in a conventional wig 20, wherein artificial
hair 3 made only of polyethylene terephthalate the cross-sectional
size of which is out of range of 50 to 70 .mu.m as the average
diameter is attached together with the second artificial hair 5, 6
to the wig base 21, the artificial hair 3 has bending rigidity
different from that of the second artificial hair 5, 6, so that it
stands up largely from the wig base 21, gives appearance separated
from the second artificial hair 5, 6, and hence is not
preferable.
[0079] Explanation is next made of a method of manufacturing
artificial hair of the present invention. First, a series of
apparatuses used for the method of manufacturing artificial hair of
the present invention will be explained.
[0080] FIG. 8 is a diagrammatical view illustrating a series of
apparatuses used for manufacturing artificial hair of the present
invention. As shown in FIG. 8, the manufacturing apparatus 30 is
constituted with a feed material tank 31 for storing polyethylene
terephthalate resin pellets as a feed material and the polyethylene
terephthalate resin pellets containing coloring materials, a melt
extruder 32 to melt and knead the feed material, a quenching bath
33 to solidify the fibrous melt discharged from an outlet 32A
formed from the molten liquid kneaded in the melt extruder 32, and
thereafter, via the three step extension thermal treatment process
each step of which comprising stretching rolls 34, 36, 38 and 40,
and dry stretching baths 35, 37 and 39, a rollup machine 41 to roll
up artificial hair 1, and an alkali denier reducing part (not
shown) to further form fine pores 2a on the fiber surface.
[0081] The melt extruder 32 is provided with a heating device to
melt polyethylene terephthalate resin pellets as a feed material
and the polyethylene terephthalate resin pellets containing
coloring materials, a kneader to disperse and mix them to be
uniform, and a gear pump to feed the molten liquid to an outlet
32A.
[0082] The outlet 32A of the discharge part 32 is provided with the
pre-determined number of holes with the pre-determined diameter,
and, as illustrated, the fiber from the outlet 32A of the discharge
part 32, after passing sequentially the quenching bath 33, the
first stretching roll 34, the first dry stretching bath 35, the
second stretching roll 36, the second dry stretching bath 37, the
third stretching roll 38, the third dry stretching bath 39, the
fourth stretching roll 40, is rolled up by the rollup machine 41,
and thereafter is alkali denier reducing treated with the alkali
denier reducing part (not shown). Here, the first to the fourth
stretching rolls 34 to 40 stretch-treat to the solidified fiber
member. First, the first stretch-treating is conducted to the fiber
member by increasing the roller speed of the second stretching roll
36 relative to the roller speed of the first stretching roll 34,
the second stretch-treating is conducted to the fiber member by
increasing the roller speed of the third stretching roll 38
relative to the roller speed of the second stretching roll 36, and
thereafter the tension applied to the fiber is relaxed by
decreasing the roller speed of the fourth stretching roll 40
relative to the roller speed of the third stretching roll 38 as the
relaxing stretching treatment to stabilize a size. Here, an oiling
device for electrostatic prevention (not shown) may be provided
between the fourth stretching roll 40 and the rollup machine
41.
[0083] FIG. 9 is a view diagrammatically illustrating an alkali
denier reducing part 45. The alkali denier reducing part 45 is
constituted with a liquid storage part 46 to store the treating
liquid containing alkali aqueous solution, a rotating cylinder 47
rotating with the fiber 100 hung down so as to soak a part of the
fiber 100 in said liquid storage part 46, and a shower part 48
provided above said rotating cylinder 47 and emit the treating
liquid to the fiber 100 hung down from the rotating cylinder 47. In
the liquid storage part 46 is stored the treating liquid containing
an alkali aqueous solution for etching polyester fiber and an
accelerating agent to accelerate hydrolytic reaction, and the
surface of fiber 100 is etched by soaking a part of fiber 100 in
the treating liquid. The rotating cylinder 47 is constituted so
that its three tubing parts extend in the rotation axis direction,
and have triangular cross-sectional shape, wherein each tubing part
has a plurality of jet-emitting orifices 47a at the opposite side
of the rotation axis to emit a jet of the treating liquid which
flew into the tubing part to the outer direction of rotation. The
shower part 48 is so constituted as to emit a jet of the treating
liquid from nozzles.
[0084] With the thus constituted alkali denier reducing part 45,
etching treatment can be applied to the fiber 100 stretched and
relaxing-treated. That is, by soaking a part of the fiber 100 in
the treating liquid, the fiber is uniformly etched to reduce the
fiber diameter. Also by rotating the rotating cylinder 47 in the
direction shown by a solid arrow in the figure, the fiber 100
rotates and moves in the direction shown by a solid line in the
figure. In this case, the treating liquid emitted from each jet
orifice 47a of the rotating cylinder 47 and from the shower part 48
is attached the outer surface of the fiber 100 hooked on the
rotating cylinder 47. At the right hand side of the rotating
cylinder 47, the moving direction of the fiber 100 (the direction
of an arrow shown by a solid line) and the moving direction by the
self weight of the treating liquid (the direction of an arrow shown
by a broken line) agree, and etching treatment is applied along the
moving direction of the fiber, that is, along the flow of the
treating liquid. On the other hand, at the left hand side of the
rotating cylinder 47, since the moving direction of the fiber 100
and the flowing direction of the treating liquid are opposite,
etching is conducted in the reverse direction of the fiber
movement. Thus, the treating liquid stained to the surface of the
fiber 100 flows vertically downward by its own weight along the
axis direction of the fiber on the surface that is, along the
length direction, and etching treatment is applied along this flow
direction. Thereby, the fiber 100 becomes thin by its alkali denier
reducing treatment, and fine pores are formed along the axis
direction on the fiber surface.
[0085] Explanation is made of a method of manufacturing artificial
hair by a series of apparatuses 30 shown in FIG. 8. Explanation is
first made of a method of manufacturing artificial hair made of a
polyester synthetic fiber with polyethylene terephthalate as its
component and containing a coloring material.
[0086] In the apparatus 30 shown in FIG. 8, polyethylene
terephthalate pellets and coloring resin pellets with polyethylene
terephthalate as a base material and containing a coloring pigment
are mixed in the pre-determined ratio and fed into a feed material
tank 31. By changing the mixing ratio of coloring resin pellets,
hair color of the artificial hair as the final product can be
changed. The mixing ratio of the coloring resin pellets to
polyethylene terephthalate pellets is the mass ratio 40:60 as
maximum for polyethylene terephthalate pellets: the coloring resin
pellets.
[0087] The pellets in the feed material tank 31 are fed into a melt
extruder 32, the melt liquid 31A formed by kneading the pellets in
the melt extruder 32 is discharged from an outlet 32A, and the
fiber-like melt is solidified by a quenching bath 33. The
temperature of the quenching bath 33 is preferably around
40.degree. C. for high productivity. If the temperature of the
quenching bath 33 is low, then the molecular structure difference
is caused by crystallization proceeding in the inner resin while
crystallization not proceeding in the outer portion by rapid
cooling regarding the outer and the inner portions of fiber-like
melt first contacted to the water upon contacting the quenching
bath 33 after molten resin is discharged, resulting in undesired
"fiber waving". If the temperature of the quenching bath 33 is too
high, the resistance to stretching of fiber-like melt becomes weak
due to too much proceeding of the fiber-like melt crystallization,
resulting in low productivity because fiber cut-off occurs
frequently upon stretching.
[0088] To the solidified fiber members, a first step of stretching
treatment is applied by a first and a second stretching rolls 34
and 36, respectively, a second step of stretching treatment is
applied by a second and a third stretching rolls 36 and 38,
respectively, and relaxing treatment is applied by a third and a
fourth stretching rolls 38 and 40, respectively. The overall ratio
as the draw ratio is 6 by the first and the second stretching
treatments.
[0089] Alkali denier reducing treatment is next applied to the
fiber after stretching treatment. More concretely, as shown in FIG.
9, the treating liquid of such alkali solution as sodium hydroxide
aqueous solution with an accelerator mixed in for acceleration of
hydrolysis is stored in a liquid storing part 46, a part of the
fiber 100 hooked on to a rotating cylinder 47 is soaked, and at the
same time, the treating liquid is emitted from a jet orifice of a
rotating cylinder 47 and a shower part 48 to the unsoaked part of
the fiber 100. Thus, the treating liquid stained to the surface of
the fiber 100 flows vertically downward by its own weight along the
axis direction of the fiber on the surface that is, along the
length direction, and etching treatment is applied along this flow
direction. Thereby, the fiber 100 becomes thin by its alkali denier
reducing treatment, and fine pores are formed along the axis
direction on the fiber surface. In this case, the treating liquid
is preferably heated to the pre-determined temperature to
accelerate hydrolysis. Then alkali stained to the fiber is
neutralized, washing-treated, and artificial hair can be
obtained.
[0090] As the polyester synthetic resin fiber of polyethylene
terephthalate and coloring pigments as components obtain
cross-sectional size and bending rigidity similar to those of
natural hair by adjusting such spinning conditions as a nozzle
diameter of an outlet 32A and the temperature of a quenching bath
33, speeds of the first to the fourth stretching rolls, such
stretching conditions as temperature of the first to the third dry
stretching baths, and further alkali denier reducing conditions,
artificial hair of bending rigidity similar to that of natural hair
can be obtained. For example, by spin rollup speed 27.9 m/min, and
the final rollup speed 155 m/min, artificial hair of bending
rigidity 6.5.times.10.sup.-3 gfcm.sup.2/strand can be obtained.
[0091] Explanation is next made of a method of manufacturing
artificial hair with polyethylene terephthalate and polybutylene
terephthalate as its components, and containing coloring
pigments.
[0092] In the manufacturing apparatus 30 shown in FIG. 8,
polyethylene terephthalate pellets, polybutylene terephthalate
pellets, and coloring resin pellets with polyethylene terephthalate
as a base material and containing a coloring pigment are mixed in
the pre-determined ratio and fed into a feed material tank 31. The
mixing ratio of the coloring resin pellets to the total pellets of
polyethylene terephthalate and polybutylene terephthalate is the
mass ratio 40:60 as maximum for the total pellets of polyethylene
terephthalate and polybutylene terephthalate: the coloring resin
pellets. The temperature of a quenching bath is preferably around
40.degree. C.
[0093] Like the method of manufacturing artificial hair of only
polyethylene terephthalate and the coloring pigments as its
components, the pellets in the feed material tank 31 are fed into a
melt extruder 32, the melt liquid 31A formed by kneading the
pellets in the melt extruder 32 is discharged from an outlet 32A,
and the fiber-like melt is solidified by a quenching bath 33. To
the solidified fiber members, like the above-mentioned case, a
first step of stretching treatment, a second step of stretching
treatment, and a relaxing treatment are applied, and alkali denier
reducing treatment is applied thereafter. Then, alkali stained to
the fiber is neutralized, washing-treated, and artificial hair can
be obtained.
[0094] By adjusting the mixing ratio of polyethylene terephthalate
pellets and polybutylene terephthalate pellets, artificial hair
having bending rigidity similar to that of natural hair can be
obtained. The mass ratio of polyethylene terephthalate and
polybutylene terephthalate is preferably in the range of 15:85 to
25:75, and more preferably 20:80. If the mass ratio is lower than
15:85, bending rigidity is too high, and if the mass ratio exceeds
25:75, bending rigidity is too low. When the artificial hair out of
the above-mentioned range is used for a wig, said artificial hair
and the wig wearer's natural hair show undesirably different
behavior. By adjusting such spinning conditions as a nozzle
diameter of an outlet 32A and the temperature of a quenching bath
33, speeds of the first to the fourth stretching rolls, such
stretching conditions as temperature of the first to the third dry
stretching baths, and further alkali denier reducing conditions,
artificial hair having optimal bending rigidity can be
obtained.
[0095] Explanation is next made of a method of manufacturing the
second artificial hair 5, 6 constituting an artificial hair bundle
of the present invention.
[0096] FIG. 10 is a diagrammatical view illustrating a
manufacturing apparatus 50 used for manufacturing the second
artificial hair 5, 6, and FIG. 11 is a diagrammatical
cross-sectional view illustrating a discharging part used for the
manufacturing apparatus of FIG. 10. As shown in FIG. 10, a
manufacturing apparatus 50 comprises a first feed material tank 51
of a polyamide resin for the sheath portion 6A, a second feed
material tank 52 of a polyamide resin for the core portion 5B, melt
extruders 51D, 52D to melt and knead the feed material supplied
from said feed material tanks 51, 52, a quenching bath 54 to
solidify the fiber-like melt discharged from an outlet 53C of the
discharge part 53 with melt liquid 61A, 52A kneaded by melt
extruders 51D, 52D, and to form a concave and convex portion on the
surface, and thereafter via three step stretching thermal treatment
processing parts with each step comprising stretching rolls 55, 57,
and 59, and dry stretching baths 56, 58, and 60, a blast machine 63
for forming further the concave and convex portion 5C on the fiber
surface, and a rollup machine 64 to roll up the artificial hair
deglossed to the desired extent with the blast machine 63.
[0097] The melt extruders 51D, 52D are provided with a heating
device to melt polyamide resin pellets, a kneader to disperse and
mix to uniformity, and gear pumps 51B, 52B to supply the melts 61A,
52A to the discharge part 53.
[0098] The fiber from the outlet 53C of the discharge part 53 goes,
as shown in the figure, via a quenching bath, stretching, and dry
stretching mechanisms, through an oiling device 61 for
electrostatic prevention, a stretching roll 62 to relax the tension
applied on the artificial hair to stabilize dimension, a blast
machine 63 for surface processing, and to a rollup machine 64.
[0099] As shown in FIG. 11, the discharge part 53 is provided with
a concentric circular double outlet from the inner circle part 53B
of which is discharged semi-aromatic polyamide resin melt 52A, and
from the outer ring part 53A surrounding said inner circle part 53B
is discharged linear saturated aliphatic polyamide resin melt 61A,
respectively.
[0100] Explanation is next made of a method of manufacturing the
second artificial hair 5, 6 with said manufacturing apparatus
60.
[0101] Using said manufacturing apparatus 50, artificial hair 5, 6
can be manufactured by melting each polyamide at appropriate
temperature in melt extruders 51D, 52D, feeding the melts to the
discharge part 53, and by discharging from an outlet 53C
semi-aromatic polyamide resin melt 52A from the inner circle part
53B of the outlet and linear saturated aliphatic polyamide resin
melt 51A from the outer ring part 53A to make fiber of sheath/core
structure.
[0102] In this case, the ratio of the volume of the linear
saturated aliphatic polyamide resin melt 51A fed for a certain time
with the gear pump 51B and the volume of semi-aromatic polyamide
resin melt 52A fed with the gear pump 52B is defined as sheath/core
volume ratio in the present invention. In order to approximate the
bending rigidity of the artificial hair 5 to that of 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 bending rigidity of artificial
hair 5, 6. If said sheath/core volume ratio is higher than 1/2,
that is, the ratio of the sheath portion 6A is large, the core
portion 5B of artificial hair 5, 6 has small effect to contribute
the increase of bending rigidity. On the other hand, if said
sheath/core volume ratio is lower than 1/7, that is, the ratio of
the core portion 5B is large, it is not preferred, for the bending
rigidity becomes too high to be close to that of natural hair.
[0103] The stretching ratio may be 5-6 times upon spinning of the
artificial hair 5, 6. Said stretching ratio is about twice as high
as that for the conventional artificial hair of nylon 6 only. For
the second artificial hair 5, 6, such as stretching ratio upon
spinning, fiber diameter, and bending rigidity can be properly
determined in accordance with the desired design. In this case, the
shape of sheath/core of artificial hair 5, 6 can be made nearly
concentric circular by properly controlling spinning
conditions.
[0104] In the spinning for the artificial hair, the artificial hair
6 can be manufactured by generating and growing spherulite for the
concave and convex portion 5C on the surface of linear saturated
aliphatic polyamide resin as the sheath portion 6A by passing the
fiber drawn from the outlet 53C through the water at 80.degree. C.
or higher in the quenching bath 54, thereby giving appearance
similar to the natural hair, and deglossing to erase unnatural
gloss.
[0105] As methods to form the fine concave and convex portion 5C on
the fiber surface, any one of the methods of blasting with such
fine particles as sand, ice, and dry-ice to the fiber surface after
spinning, or of chemical treatment of the fiber surface, or proper
combination of them may be adopted, in addition to the
above-mentioned spherulite formation and growth.
[0106] In order to give the proper color and appearance as the
artificial hair 5, 6, a pigment and/or dye may be formulated during
spinning, or the artificial hair 5, 6 itself may be dyed after
spinning.
[0107] As described above, since the second artificial hair 5, 6
has the sheath/core structure with polyamide resins of different
bending rigidities, the artificial hair 5, 6 of the bending
rigidity 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 5C on the surface of the artificial hair 5, the
natural gloss similar to natural hair can be given, thereby so can
the natural appearance as hair.
EXAMPLES
Example 1
[0108] Explanation is next made in detail of examples of the
present invention.
[0109] Using the spinning machine 30 shown in FIG. 8, artificial
hair with polyethylene terephthalate as its component was
manufactured. As the feed material for artificial hair,
polyethylene terephthalate pellets (TOYOBO, LTD., density 1.40
g/cm.sup.3, melting point 255.degree. C.) and coloring resin
pellets with polyethylene terephthalate resin as a base material
and pigment weight % of black, yellow, orange, and red are 6%, 6%,
5% and 5%, respectively, were used.
[0110] The spinning conditions are such that melting temperature of
pellets is 270.degree. C. as discharging temperature from the
outlet, and a nozzle with 15 holes of diameter 0.7 mm was provided
to the outlet. Temperature of the quenching bath 33 was set at
40.degree. C.
[0111] For spinning conditions, the cross-sectional average
diameter of artificial hair after alkali denier reducing treatment
was made 65 .mu.m by adjusting the speeds of the first to the
fourth stretching rolls 34 to 40, respectively. That is, the speed
of the second stretching roll 36 was set as 4.6 times that of the
first stretching roll 34, the speed of the third stretching roll 38
was set as 1.3 times that of the second stretching roll 36, and the
speed of the fourth stretching roll 40 was set as 0.93 times that
of the third stretching roll 38. Also, temperature of the first dry
stretching bath 35 was set at 130.degree. C. as the first
stretching temperature, temperature of the second dry stretching
bath 37 was set at 180.degree. C. as the second stretching
temperature, and temperature of the third dry stretching bath 39
was set at 180.degree. C. as the relaxing stretching
temperature.
[0112] As the alkali denier reducing condition, an alkali aqueous
solution was used wherein cathiosol (Takamatsu Oil and Fat, Ltd.)
was added to 0.5 weight % as a hydrolysis accelerator to 5 weight %
sodium hydroxide aqueous solution. Also, the bath ratio was set as
the mass ratio of the treated matter:treating solution=1:30, the
treating temperature about 100.degree. C., and the treating time
was set as 60 minutes so as to attain alkali denier reducing ratio
as 10 to 20%.
[0113] Table 1 shows physical properties of artificial hair with
and without alkali denier reducing treatment.
TABLE-US-00002 TABLE 1 Alkali Weight Reducing Fiber Dia. Strength
Stretch Treatment (.mu.m) (kgf/mm.sup.2) (%) before 75.1 84.7 19.6
after 66.1 63.4 12.2
[0114] As is seen from Table 1, the diameter of artificial hair was
reduced from 75.1 .mu.m to 66.1 .mu.m by alkali denier reducing
treatment. The strength was decreased from 84.7 kgf/mm.sup.2 to
63.4 kgf/mm.sup.2. The elongation ratio was decreased from 19.6% to
12.2%.
[0115] FIG. 12 is a view showing a scanning electron microscopic
image of the artificial hair manufactured in Example 1. The
acceleration voltage of electrons is 15 kV, and the magnification
is 800. As is seen from FIG. 12, fine pores were seen to be formed
in the direction perpendicular to the length direction of
artificial hair on its surface, that is, long in the axis direction
of a fiber. Said fine pores can cause the light to attain
deglossing effect. The cross-sectional size of artificial hair
turned out to be about 65 .mu.m as the average diameter.
Example 2
[0116] Artificial hair of the cross-sectional size 50 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
Example 3
[0117] Artificial hair of the cross-sectional size 55 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
Example 4
[0118] Artificial hair of the cross-sectional size 60 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
Example 5
[0119] Artificial hair of the cross-sectional size 70 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
[0120] Comparative Examples 1 to 3 are shown next in contrast to
Examples 1 to 5.
Comparative Example 1
[0121] Artificial hair of the cross-sectional size 45 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
Comparative Example 2
[0122] Artificial hair of the cross-sectional size 75 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
Comparative Example 3
[0123] Artificial hair of the cross-sectional size 80 .mu.m as the
average diameter was manufactured as in Example 1 but with the
stretching condition changed.
[0124] The results of bending rigidities of artificial hairs
manufactured in Examples 1 to 5 and Comparative Examples 1 to 3 are
shown next. The measurement of bending rigidities was performed in
the environment of temperature 20.degree. C. and humidity 40%.
[0125] As the measurement of bending rigidity of a fiber, KAWABATA
method of measurement and its principle are widely known for
textile, and its improved version Single Hair Bending Tester
(KATOTECH, LTD., Model KES-FB2-SH) was used to measure bending
rigidity of artificial hair. As the method of measurement for any
case of artificial and natural hair as a sample in Examples and
Comparative Examples of the present invention, each one strand of 1
cm was bent at equal speed in an arc shape to a certain curvature,
the small bend moment accompanying it was detected, and the
relationship of the bend moment and the curvature was measured.
Bending rigidity was obtained therefrom by bend moment/curvature
change. Typical measurement conditions are shown below.
(Measurement Conditions)
[0126] Distance between Chucks: 1 cm
[0127] Torque Detector Detection of Torque of Tortion Wire (Steel
Wire)
[0128] Torque Sensitivity: 1.0 gfcm (at Full Scale 10V)
[0129] Curvature: .+-.2.5 cm.sup.-1
[0130] Rate of Bend Deviation: 0.5 cm.sup.-1/sec
[0131] Measurement Cycle: 1 Round Trip.
Here, a chuck is a mechanism for clipping said each hair of 1
cm.
[0132] Table 2 shows measurement results of bending rigidities of
artificial hairs manufactured in Examples 1 to 5 and Comparative
Examples 1 to 3. FIG. 13 is a graph showing the relationship of
bending rigidity with regard to the cross-sectional diameter of
artificial hair manufactured in Examples 1 to 5 and Comparative
Examples 1 to 3. The ordinate axis of the figure represents bending
rigidity (gfcm.sup.2/strand), and the abscissa axis represents the
cross-sectional diameter of artificial hair (.mu.m).
TABLE-US-00003 TABLE 2 Cross-sectional Bending Average Diameter
Rigidity .times. 10.sup.-3 (.mu.m) (gf cm.sup.2/strand) Example 1
65 7.44 Example 2 50 6.7 Example 3 55 6.86 Example 4 60 7.12
Example 5 70 7.67 Comp. Ex. 1 45 6.37 Comp. Ex. 2 75 8.06 Comp. Ex.
3 80 8.35
[0133] As is seen from Table 2 and FIG. 13, bending rigidity
increased linearly for the artificial hair of polyethylene
terephthalate as its main component as its cross-sectional size
increases. That is, as the average diameter increased as 45, 50,
55, 60, 65, 70, 75 and 80 .mu.m, bending rigidity increased,
respectively, 6.37.times.10.sup.-3, 6.70.times.10.sup.-3,
6.86.times.10.sup.-3, 7.12.times.10.sup.-3, 7.44.times.10.sup.-3,
7.67.times.10.sup.-3, 8.06.times.10.sup.-3 and 8.35.times.10.sup.-3
gfcm.sup.2. Since bend rigidities of natural hairs have wide
personal deviation, hairs were collected from 25 males and 38
females of respective ages between 20 and 50 years old, bending
rigidities of the samples of 80 .mu.m diameter were measured in the
same measurement environment, that is, in the environment of
temperature 20.degree. C. and humidity 40%. Their maximum value was
7.4.times.10.sup.-3 gfcm.sup.2/strand, their minimum value was
6.6.times.10.sup.-3 gfcm.sup.2/strand, and their average was
7.1.times.10.sup.-3 gfcm.sup.2/strand. From this result, it is
similar to that of natural hair within the range of about
6.5.times.10.sup.-3 to 7.8.times.10.sup.-3 gfcm.sup.2/strand in the
environment of temperature 20.degree. C. and humidity 40%. Judging
from these results, the artificial hairs manufactured in Examples 1
to 5 have bending rigidities similar to that of natural hair, but
those manufactured in Comparative Examples 1 to 3 have bending
rigidities out of the range of natural hair. From the above, it is
seen that, in order for artificial hair of polyethylene
terephthalate as its component to have bending rigidity similar to
that of natural hair, its size may be 50 to 70 .mu.m. Also, it was
confirmed by a scanning electron microscopic images that fine pores
were formed, as in Example 1, to artificial hair manufactured in
Examples 2 to 5 and Comparative Examples 1 to 3.
Example 6
[0134] Polyester artificial hair 2 was manufactured using a
manufacturing apparatus 30 shown in FIG. 8. As the material of
artificial hair, polyethylene terephthalate pellets (TOYOBO, LTD.,
density 1.40 g/cm.sup.3, melting point 255.degree. C.),
polybutylene terephthalate pellets (Mitsubishi Engineering
Plastics, LTD., density 1.31 g/cm.sup.3, melting point 224.degree.
C.), and coloring resin pellets of black, yellow, orange, and red
pigment weight % being 6:6:5:5, respectively and with polyethylene
terephthalate resin base were used. The mixing ratio of
polybutylene terephthalate pellets to polyethylene terephthalate
pellets was varied as 0 to 75% by mass ratio, and seven kinds of
artificial hair were manufactured. The conditions such as spinning,
stretching, and alkali denier reducing treatment are same as in
Example 1.
[0135] Table 3 shows bending rigidity of artificial hair
manufactured in Example 4, and shows the values before and after
alkali denier reducing treatment with polybutylene terephthalate
mixing ratio as a parameter. FIG. 14 is a graph converted from
Table 3, showing bending rigidity with regard to the mixing ratio
of polybutylene terephthalate mass. The ordinate axis represents
bending rigidity (gfcm.sup.2/strand), and the abscissa axis
represents the mixing ratio of polybutylene terephthalate to the
whole pellets by mass, PBT/(PET+PBT) (%). Of the plots,
.diamond-solid. (diamond) is values before, and .box-solid.
(square) is values after alkali denier reducing treatment. The
measurement conditions were temperature 22.degree. C. and humidity
40%.
TABLE-US-00004 TABLE 3 Bending Rigidity .times. 10.sup.-3 gf
cm.sup.2/strand PBT Mixing before Alkali Weight after Alkali Weight
Ratio % Reducing treatment Reducing treatment 0 19.79 11.66 10
18.07 9.70 20 16.35 8.32 30 14.64 7.68 50 11.10 6.40 60 9.88 5.75
75 6.79 4.78
[0136] As is seen from Table 3 and FIG. 14, when the ratio of
polybutylene terephthalate was increased as the artificial hair
component, bending rigidity decreased both before and after alkali
denier reducing. Before alkali denier reducing treatment, bending
rigidity was about 1.6.times.10.sup.-2 gfcm.sup.2/strand for mixing
ratio 20%, whereas it decreases monotonously to about
6.7.times.10.sup.-3 gfcm.sup.2/strand when mixing ratio was
increased to 75%. Also, after alkali denier reducing treatment,
bending rigidity was about 1.2.times.10.sup.-2 gfcm.sup.2/strand
for mixing ratio 0%, whereas it decreases monotonously to about
8.3.times.10.sup.-3 gfcm.sup.2/strand when mixing ratio was
increased to 20%, and about 5.7.times.10.sup.-3 gfcm.sup.2/strand
for mixing ratio 60%.
[0137] The cross-sectional diameter of seven kinds of artificial
hair of different mixing ratio of polybutylene terephthalate was
81.3 .mu.m as an average before alkali denier reducing treatment,
and 71.1 .mu.m as an average after alkali denier reducing
treatment.
[0138] From the results above, bending rigidity of artificial hair
can be lowered by increasing mixing ratio of polybutylene
terephthalate, and artificial hair of bending rigidity similar to
that of natural hair (6.5 to 7.8.times.10.sup.-3 gfcm.sup.2/strand)
can be obtained. For example, in case without alkali denier
reducing treatment, mixing ratio of polybutylene terephthalate may
be about 70 to 80%, and in case with alkali denier reducing
treatment, mixing ratio of polybutylene terephthalate may be about
20 to 60%.
[0139] FIG. 15 is a graph showing the bending rigidity before and
after the alkali denier reducing treatment in case of 20% and 60%
of the mixing ratio of polybutylene terephthalate. The ordinate
axis represents bending rigidity (gfcm.sup.2/strand), and the
abscissa axis represents mixing ratio of polybutylene
terephthalate. As is seen from FIG. 15, bending rigidity was about
1.6.times.10.sup.-2 gfcm.sup.2/strand for mixing ratio 20%, and was
decreased to about 8.3.times.10.sup.-3 gfcm.sup.2/strand by alkali
denier reducing treatment. The cross-sectional diameter of
artificial hairs of mixing ratio 20% and 60% of polybutylene
terephthalate was 80.4 .mu.m as an average before alkali denier
reducing treatment, and 71.1 .mu.m as an average after alkali
denier reducing treatment.
[0140] It is seen from the above that alkali denier reducing
treatment is effective in a method of manufacturing artificial hair
made of polyester synthetic resins for reducing the cross-sectional
diameter of artificial hair, or for reducing bending rigidity
similar to natural hair.
Example 7
[0141] As in Example 1, thermal treatment was applied to artificial
hair made of polyester fiber after alkali denier reducing treatment
having bending rigidity about 6.5.times.10.sup.-3 gfcm.sup.2/strand
and the diameter about 66 .mu.m. Said thermal treatment is a mock
test of curling process, and was conducted as holding artificial
hair rolled on a pipe of a diameter 30 mm in the environment of
180.degree. C. for 2 hours. The shrinkage ratio of artificial hair
after thermal treatment was measured as 0.77%.
Example 8
[0142] As in Example 1, the same thermal treatment as in example 7
was applied to artificial hair made of polyester fiber without
alkali denier reducing treatment unlike Example 7 having bending
rigidity about 1.2.times.10.sup.-2 gfcm.sup.2/strand and the
diameter about 75 .mu.m. The shrinkage ratio of artificial hair
after thermal treatment was measured as 1.55%.
[0143] Comparison of Examples 7 and 8 revealed that thermal
shrinkage ratio by thermal treatment was lowered to half by alkali
denier reducing treatment.
Example 9
[0144] Next, thermal treatment was preliminarily applied to the
second artificial hair of an artificial hair bundle, and the
influence was confirmed with and without preliminary treatment on
the second artificial hair as a mock test of curling process by
mixing with the first artificial hair.
[0145] A first thermal treatment was applied to artificial hair
having a sheath/core structure and bending rigidity 3.9 to
7,8.times.10.sup.-3 gfcm.sup.2/strand, and a second thermal
treatment was applied thereafter. A core portion of artificial hair
was made of nylon MXD6 (Mitsubishi Gas Chemical Co., Ltd., Trade
name MX nylon) as a polyamide resin, and a sheath was made of a
copolymer of nylon 6 and nylon 66 (NY6/NY66) and nylon 6 (NY6)
containing coloring materials. The first thermal treatment
corresponds to a pre-treatment, as holding artificial hair in the
stretched state without rolling on a pipe in the environment of
160.degree. C. for 30 minutes. The second thermal treatment was a
curling process corresponding to a main treatment, like thermal
treatment in Examples 3 and 4, as holding artificial hair rolled on
a pipe of a diameter 30 mm in the environment of 180.degree. C. for
2 hours.
Comparative Example 4
[0146] Comparative Example 4 is shown next in contrast to Example
9. In Comparative Example 4, the first thermal treatment was not
applied but the second thermal treatment to the same artificial
hair as in Example 9 was applied.
[0147] Explanation will be made of the results of Example 9 and
Comparative Example 4. Table 4 shows the results of Example 9 and
Comparative Example 4, showing thermal shrinkage ratio of
respective artificial hair, the values after the first thermal
treatment and the values after the first and the second thermal
treatments as the result of Example 9, and the values after the
second thermal treatment only as the result of Comparative Example
4. FIG. 16 is a graph of Table 4, showing thermal shrinkage ratio
with regard to bending rigidity of each artificial hair. The
ordinate axis represents thermal shrinkage ratio (%), and the
abscissa represents bending rigidity (gfcm.sup.2/strand). Here, the
plot .diamond-solid. (diamond) represents bending rigidity after
the first thermal treatment, the plot .box-solid. (square)
represents bending rigidity after the first and the second thermal
treatments, and the plot .tangle-solidup. (triangle) represents
bending rigidity after the second thermal treatment only as the
result of Comparative Example 4.
TABLE-US-00005 TABLE 4 Thermal Contraction Ratio (%) Example 9
Bending after First after Second Comp. Ex. 4 Rigidity .times.
10.sup.-3 Thermal Thermal Second Thermal (gf cm.sup.2/strand)
Treatment Treatment Treaatment Only 3.90 3.11 0.17 1.12 5.20 3.54
0.53 1.03 6.50 3.63 0.08 1.12 7.80 4.58 0.18 1.38
[0148] As is seen from Table 4 and FIG. 16, artificial hair shrinks
thermally by the first, or the second, or both thermal treatment.
As a result of Example 9, that is, the higher the bending rigidity,
the higher is the thermal shrinkage ratio by the first thermal
treatment, and it is about 3% for the artificial hair of bending
rigidity about 3.9.times.10.sup.-3 gfcm.sup.2/strand, but about
4.6% for the artificial hair of bending rigidity about
7.8.times.10.sup.-3 gfcm.sup.2/strand. The thermal shrinkage ratio
by the first and the second thermal treatment is less than 1%
regardless of the value of bending rigidity, and in the range of
0.53 to 0.08%. On the other hand, as a result of Comparative
Example 4, that is, if only the second thermal treatment is
applied, the thermal shrinkage ratio does not depend upon the value
of bending rigidity, and is about 1 to 1.4%.
[0149] Comparison is made between Examples 7 and 9 and Comparative
Example 4. Since, according to the result of Example 7, the thermal
shrinkage ratio of polyester artificial hair as the first
artificial hair is 0.77%, and according to the result of
Comparative Example 4, the thermal shrinkage ratio of polyamide
artificial hair as the second artificial hair is higher than 1%,
the second artificial hair shrinks more than the first artificial
hair. Thus, if this treatment is applied by mixing polyester
artificial hair used in Example 7 and polyamide artificial hair
used in Comparative Example 4, the polyester artificial hair
neighboring the polyamide artificial hair tends to shrink similarly
to the polyamide artificial hair. However, if the pre-treatment is
not applied to the polyamide artificial hair and this treatment is
applied by mixing polyester artificial hair, then the polyester
artificial hair of lower shrinkage than the polyamide artificial
hair can not shrink similarly to the polyamide artificial hair. As
a result, undesired wavy steps are caused to an artificial hair
bundle.
[0150] On the other hand, according to the result of Example 9, the
thermal shrinkage ratio of polyamide artificial hair as the second
artificial hair is less than 0.5%, and according to the result of
Example 7, the thermal shrinkage ratio of polyester artificial hair
as the first artificial hair is 0.77%, and hence the difference of
both is small. Thus, by pre-treatment to the polyamide artificial
hair as the second artificial hair to cause thermal shrinkage,
curling treatment by mixing with the polyester artificial hair as
the first artificial hair causes similar shrinkage to the first and
the second artificial hairs, and hence wavy steps do not occur.
[0151] From the above, in case of making up an artificial hair
bundle of the present invention, wavy steps can be prevented from
occurring in the first artificial hair upon curling treatment to
the artificial hair bundle by applying in advance thermal treatment
to the polyamide fiber as the second artificial hair to make it
similar to or lower than the first artificial hair.
[0152] As described above, according to the present invention,
artificial hair having similar feeling to that of natural hair can
be provided by melt-spinning with polyethylene terephthalate as a
main component, applying stretching and alkali denier reducing
treatments so as to have similar cross-sectional size to that of
natural hair, and making artificial hair by melt-spinning with
polyethylene terephthalate and polybutylene terephthalate in the
pre-determined mass ratio so as to have similar size and bending
rigidity to those of natural hair. The artificial hair made of
polyester fiber does not bundle by itself, can prevent bundling of
the artificial hair made of polyamide fiber, thereby can attain
similar bending rigidity to that of natural hair. Further, by
making the artificial hair made of polyester fiber the first
artificial hair, and by mixing it into the second artificial hair
made of polyamide fiber and having similar size and bending
rigidity to those of natural hair in the pre-determined ratio,
bundling of the second artificial hair can be suppressed.
Therefore, in a wig with these artificial hairs attached to the wig
base, when set to the hairstyle according to the wig wearer's
preference, the second artificial hair does not bundle, and the
bending rigidities of the first and the second artificial hairs can
be approximated to that of natural hair, thereby it behaves
similarly to natural hair having natural feeling.
[0153] The best mode for carrying out the present invention
explained above may be variously modified within the appropriate
range of the claimed invention.
* * * * *