Note: Descriptions are shown in the official language in which they were submitted.
~ 1 3 3 3 7 3 9
POLYVINYL CHLORIDE FIBERS FOR ARTIFICIAL HAIR AND
- PRODUCTION OF THE SAME
The present invention relates to polyvinyl chlo-
ride fibers for artificial hair and a process for producing
the same. More particularly, the present invention relates
to polyvinyl chloride fibers for artificial hair having good
processability, function and cosmetic or beauty properties.
The fibers have a good feeling and are suitable for use as
wigs, hair accessories and doll hair.
As artificial hair fibers, modacrylic fibers (e.g.
fiber comprising a copolymer of 50 % by weight of acrylo-
nitrile and 50 % by weight of vinyl chloride), polyvinyl
chloride fibers, polyvinylidene chloride fibers and poly-
ester fibers are commercially available.
Since none of the conventional fibers satisfy
all the properties required for hair fibers, e.g. heat
resistance, curling properties, feeling and the like, hair
products, e.g. wigs which satisfy various requirements
have not yet been produced with a single kind of
fiber. Until now hair products which have specific proper-
ties corresponding to the kind of fiber used have been
produced and used.
r
A-
1 333739
Typical beauty properties required for artifi-
cial hair fibers are as follows:
Properties relating to curling
tl) Brush accommodation
A direction of curling is easily changed with
brushing and curling does not come loose.
(2) Maintenance of curling
Spirally curled plural hairs (for example, 100
hairs) maintain their shape without drooping by their own
weight.
(3) Maintenance of up-curling
Plural hairs (for example, 100 hairs) are bundled
and up-curled, that is the hairs are spirally curled
upwardly with their roots down. When the up-curled hairs
are swung, the hair bundle at the curled part does not come
loose and the up-curled shape is maintained.
(4) Resiliency of spirally curled hair
When the spirally curled hairs are suspended and
swung up and down, they swing rhythmically while the direc-
tion of curling does not shift right and left.
Organoleptic properties
(5) Voluminess
When brushing, the roots of hairs or skins do not
appear and a natural puff suitable for each hair style is
maintained.
(6) Feel (close to natural hair )
''P~.
~ ~ 333739
When the hair is h~ld between the fingers, it gives a
soft and voluminous feeling, and when the hair is drawn
between the fingers, it gives a smooth and slipping feeling.
(7) Gloss
The hair has gloss similar to natural hair.
(8) Combability
When the hairs are combed, there is no resistance
in the middle portion, nor is the comb caught at the tips of
the hairs and the comb moves through the hairs smoothly.
As described above, conventional artificial
hair fibers have their own advantages and disadvantages.
For example, the modacrylic fibers have volumi-
ness, feeling and gloss similar to natural hair and good
combability although reasons for these properties are not
known, while they have poor curling properties such that
their bundle tends to be twisted when curled (poor mainte-
nance of up-curling), their curling comes loose as time
passes (poor maintenance of curling) or they have less
resiliency. Because of these reasons, the modacrylic fibers
are mainly used in products with a natural style (namely,
hairs with slight wave or no wave).
The polyvinyl chloride fibers have good curling
properties. For example, they are easily curled although
the reason for this is not known, the curled hairs do not go
out of shape as time passes, and when spirally curled, they
have a r~ nt feeling. However, they lack the organoleptic
'~
1 333739
. - 4 -
properties, that is, they have poor voluminess, or feeling
and gloss close to synthetic fibers. Then, they are mainly
used in products of wave style or straight style (in which
only the tip parts are curled).
In view of the above circumstances, hair product
makers have tried to use a combination or two or more kinds
of synthetic fibers to produce the hair products which
satisfy all the beauty characteristics. Since the fibers
have different heat resistance, it is difficult to select
adequate processing conditions. Further, the fibers have
different hue and gloss, the hair products have an
unnatural appearance.
One object of the present invention is to provide
a synthetic fiber from which a hair product satisfying
various beauty requirements can be produced.
Another object of the present invention is to
provide a synthetic fiber which can provide a wide variety
a hair styles.
According to the present invention, there is
provided a vinyl chloride base fiber for artificial hair
having an H-shaped cross section or a dumbbell-shaped cross
section and a fineness of 40 to 70 deniers and which
comprises a copolymer comprising 85 to 70% by weight of
repeating units derived from vinyl chloride, 15 to 30% by
weight of repeating units derived from acrylonitrile and 0
to 5% by weight of repeating units derived from at least
-
~.~
1 333739
one ethylenically unsaturated "Y,.,~."~, copolymerizable therewith.
: In drawings which represent preferred embcdiments of
the present invention:
Fig. l is an H-shaped cross section of the fiber
of the present invention, and
Fig. 2 is an dumbbell-shaped cross section of the
fiber of the present invention.
The vinyl chloride units in the copolymer of the
present invention impart a well knit curl shape which does
not come loose as time passes to the artificial hair fibers
and resiliency when the hairs are spirally curled. The
acrylonitrile units impart feeling or voluminess close
to natural hair and good combability.
When the content of the vinyl chloride units is
less than 70 % by weight, the fiber does not have satis-
factory curling properties, e.g. knitting of curl shape,
maintenance of curling, resiliency and the like. When the
content of the vinyl chloride exceeds 85 % or the content of
the acrylonitrile units is less than 15 % by weight, the
fiber does not have satisfactory organoleptic properties
which are imparted by the acrylonitrile units, e.g. feeling
and volllnin~s close to that of natural hair, or cnmh~h;l;ty.
The optionally contained ethylenically unsaturated
monomer improves other properties,e.~. dyeing properties or
processability of the fiber. Examples of such a ~ n~ are
'A
-- 6
1 333739
acrylic acid and methacrylic acid or their salts or esters,
- vinylidene chloride, vinyl bromide, vinylidene bromide,
methallylsulfonic acid and styrenesulfonic acid or their
salts, acrylamide, vinyl acetate and the like.
The copolymer is preferably used independently,
although it can be used in combination with a small amount
of at least one other resin.
Examples of the other polymers are vinyl chloride
resin, polyacrylonitrile, vinyl chloride-acrylonitrile
copolymer, vinylidene chloride-acrylonitrile copolymer and
the like. The amount of the other resin is determined
according to the final use of the fiber, and is usually not
more than 30 % by weight, preferably not more than 20 % by
weight based on the total weight of the polymers.
The cross sectional profile of the fiber of the
present invention is not critical. Although the cross sec-
tion of a round shape, a horseshoe shape, a star shape or a
Y shape may achieve the objects of the present invention,
the fiber of the present invention preferably has a cross
section of an H shape or a dumbbell shape as shown in Figs.
l and 2, respectively since the fiber with the H shaped or
dumbbell shaped cross section has gloss, depth of color and
flexibility which are close to natural hair.
The difference between the H shape and the dumb-
bell shape is as follows:
~A
1 333739
When the vertical size and the horizontal size of
the cross section are "a" and "b", respectively, the H
shaped cross section has the ratio of b/a of less than 1.5
and preferably not less than 0.5 as shown in Fig. 1, and the
dumbbell shaped cross section has the ratio of b/a of not
less than 1.5 and preferably not larger than 3 as shown in
Fig. 2.
The fineness of the fiber is not critical to the
present invention, and any fiber having a fineness which
is suitable for artificial hair can be used. Prefe-
rably, the fiber has a fineness of 40 to 70 deniers. When
the fineness is less than 40 deniers, the fiber may be too
thin for a hair fiber so that curling maintenance
may deteriorate. When the fineness is larger than 70
deniers, the fiber may be too thick and stiff for arti-
ficial hair.
Now, production of the artificial hair fiber
of the present invention is detailed.
The copolymer to be used in the present invention
may be prepared by any conventional polymerization
method in an aqueous system, e.g. suspension polymeri-
zation or emulsion polymerization.
If desired, the other resin is added to the
copolymer, and the copolymer or the mixture of the copolymer
and the cther resin is dissolved in a solvent to form a
solution having a concentration of from 25 to 35 ~. Examples of
i~
1 33s739
the solvent are dimethylformamide, dimethylacetoamide,
dimethylsulfoxide, acetone, acetonitrile, etc.
The polymer solution as such can be used as a
spinning solution, although any conventional additive,
e.g. titanium oxide, colloidal silica, calcium sulfate,
aluminum hydroxide and the like~may be added to the spinning
solution to improve the properties of the spun fiber.
The spinning solution is spun by a conventional
wet or dry spinning method, dried and drawn followed by
heating at a temperature of 100 to 140C by dry heat or at a
temperature of 80 to 110C by wet heat.
The heating after drawing relieves strain of the
fiber generated during drawing and is usually carried out
for 0.5 to 5 minutes. When the dry he-at is applied at a
temperature lower than 100C or the wet heat is applied at a
temperature lower than 80C, the produced hair fibers easily
shrink at a temperature at which the fibers aree set in the
desired style, for example, 80 to 110C during the produc-
tion of hair products from the fibers. When the dry heat is
applied at a temperature higher than 140C or the wet heat
is applied at a temperature higher than 110C, the fibers
are fused together during heat treatment at such high tem-
peratures.
The present invention will be illustrated by the
following Examples, in which "%" is by weight unless other-
wise indicated.
r~
` 1 333739
In the following Examples, the beauty properties
of the fibers are evaluated as follows:
Fibers cut to a predetermined length or fibers cut
to a predetermined length and arranged in parallel with each
s other are wound around an aluminum pipe having a diameter of
10 to 40 mm according to the desired style and heat treated in an oven
at a temperature of 80 to 110C or about 180C in the case of
polyester fibers. Then, the curled fibers are fixed on a
cap base with a sewing machine or a filling needle to
produce an art1ficial head of hair and subjected to the
evaluations on the properties listed in the beginning of the
specification.
The cross section of the fiber is observed with a
scanning electron microscope.
Example 1
By emulsion polymerization using a redox catalyst,
73 % of vinyl chloride and 27 % of acrylonitrile were
copolymerized. The copolymer was dissolved in acetone to
obtain a spinning solution of a resin concentration of 30 %.
Then, the spinning solution was spun through an orifice
having H shaped pores, coagulated, washed with water, dried
and drawn followed by heat treating with dry heat at 125C
to obtain fibers having a fineness of 55 deniers and an H
shape cross section.
1 0
1 333739
The beauty properties of the fibers were evalua-
ted. The results are shown in Table 1.
From the results in Table 1, it can be seen that
the fibers had excellent properties.
Table 2 includes the accommodation of the fibers
to various styles. These results indicate that the fibers
of the present invention can be arranged in various styles.
Example 2
In the same manner as in Example 1, a spinning
10 solution was prepared and spun through an orifice having
dumbbell shaped pores, coagulated, washed with water, dried
and drawn followed by heat treating with dry heat at 125C
to obtain fibers having a fineness of 55 deniers and a
durbbell shaped cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table 1.
From the results in Table 1, it can be seen that
the fibers had excellent properties.
Table 2 includes the accommodation of the fibers
20 to various styles. These results indicate that the fibers
of the present invention can be arranged in various styles.
Example 3
In the same manner as in Example 1, a spinning
solution was prepared and spun through an orifice having
25 round pores, coagulated, washed with water, dried and drawn
~ollowed by heat treating with dry heat at 125C to obtain
~A
1 333739
fibers having a fineness of 55 deniers and a horseshoe shaped
cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table l.
From the results in Table l, it can be seen that
the fibers had very good properties, although the feeling
and gloss of these fibers were slightly inferior to the
fibers having the H shaped cross section or the dumbbell
shaped cross section.
Example 4
By emulsion polymerization using a redox catalyst,
80 % of vinyl chloride, l9 % of acrylonitrile and l % of
sodium styrenesulfonate were copolymerized. The copolymer
was dissolved in a mixed solvent of acetone and benzene
(weight ratio of 80:20) to obtain a spinning solution of a
resin concentration of 28 %. Then, the spinning solution
was spun through an orifice having round pores, coagulated,
washed with water, dried and drawn followed by heat treating
with wet heat at 90C to obtain fibers having a fineness of
60 deniers and a horseshoe shaped cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table l.
From the results in Table l, it can be seen that
the fibers had excellent properties as in Example 3.
1 333739
,
Example 5
In acetone, 85 % of the copolymer prepared in
Example l and 15 ~ of a copolymer of S0 % vinyl chloride,
- 49 % of acrylonitrile and l % of sodium styrenesulfonate
were mixed and dissolved to prepare a spinning solution.
Then, the a spinning solution was spun through an orifice
having dumbbell shaped pores, coagulated, washed with water,
dried and drawn followed by heat treating with dry heat at
130C to obtain fibers having a fineness of 55 deniers and a
horseshoe shaped cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table 1.
From the results in Table 1, it can be seen that
the fibers had excellent properties as in Examples 3 and 4.
Comparative Example l
By emulsion polymerization using a redox catalyst,
60 % vinyl chloride and 40 % acrylonitrile were
copolymerized. The copolymer was dissolved in acetone to
obtain a spinning solution of a resin concentration of 28 %.
Then, the spinning solution was spun through an orifice
having round pores, coagulated, washed with water, dried and
drawn followed by heat treating with dry heat at 135C to
obtain fibers having a fineness of 55 deniers and a
horseshoe shaped cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table l.
~ '
A
- 13 -
~ 333739
Comparative Example 2
By emulsion polymerization using a redox catalyst,
90 % vinyl chloride and 10 % acrylonitrile were
copolymerized. The copolymer was dissolved in a mixed
solvent of acetone and benzene to obtain a spinning solution
of a resin concentration of 26 %.
Then, the spinning solution was spun through an orifice
having round pores, coagulated, washed with water, dried and
drawn followed by heat treating with wet heat at 90C to
obtain fibers having a fineness of 55 deniers and a
horseshoe shaped cross section.
The beauty properties of the fibers were evalua-
ted. The results are shown in Table 1.
Comparative Examples 3-S
With a commercially available modacrylic fiber
(50 % vinyl chloride and 49 % acrylonitrile) (Comparative
Example 3), polyvinyl chloride fiber (Comparative Example 4)
or polyester fiber (Comparative Example 5), the beauty pro-
perties were evaluated. The results are shown in Table l.
Table 2 includes the accommodation of the fibers to various
styles.
1 333739
.~
D ~
O D
U~
o
CJ
. ,~
E
o c
.) ~ C~
C '~ ,c
_, ., ~
C: o U
._
o
., Cl
~ u J
~-- C
~ o C
~.,~
~C U
.~
co
Ul . ,.
V ~ ~ a a: ~ ~ a
.~ I
~ I ~
r~
O D tl D .~
0 ~ D
OU ''
C~ ~ ' ._ U _~ O _~ V
u~ o ~ a ~ c
~ 'J U '~ V
OJ J
~, ~ a~ ~ ~ c a~ ~ . ~ u o o
:~ ~ . OJ -' C D ~ X O O
U ~ U
~:: C
C E
x .-- o ~ ~ ~
~:~ C Z O
. I
t 333739
Table 2
;
Example Curly Wave Straight Combi- Afro Natural
No. nation
1 B A B A A A
2 B B . A A A A
C. 3 B C D A B A
C. 4 C D ` A B C D
C. 5 B D : D D A D
Note: A: Very suitable
B: Suitable
C: Less suitable
D: Unsuitable
$ ~ `
.~ .
