JP2009221645A - Fiber having modified cross section, and makeup cosmetic - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fiber having modified cross section giving excellent light dispersion and reflection actions and skin feeling with glossy appearance when added into cosmetics and applied, and at the same time, having smooth use feeling without feeling of a foreign body, in addition, volume-up effects when used as mascara, and makeup cosmetics containing the fiber having the modified cross section. <P>SOLUTION: The fiber having modified cross section has a cross section of a filament vertically cut to the longitudinal fiber axis exhibiting a shape in which two circles having openings are connected at least one point. In the fiber, the openings of two circles are connected without being blocked, the maximum length connecting optional two points in a cross sectional shape is ≥1.1 times of the diameter of a circle having the maximum diameter, the maximum length is 5-100 μm, both two circles have each 30-140° angle of opening, and monofilament fineness is 1.0-7.0 dtex. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a modified cross-section fiber that is preferably contained in cosmetics. The cross-sectional shape of a single yarn exhibits a shape in which two circular shapes having openings are connected, thereby diffusing and reflecting light. The present invention relates to a modified cross-section fiber that can provide a cosmetic material that is excellent in quality and has a smooth feeling of use with no foreign matter feeling.

  Moreover, this invention relates to the makeup cosmetics containing such a modified cross-section fiber of this invention.

  Conventionally, fibers are blended in makeup cosmetics such as foundations in order to enhance the makeup effect and give a smooth feeling of use. Patent Document 1 proposes a cosmetic material in which irregular cross-section fibers having dents in the cross section are dispersed.

  By using the modified cross-section fiber described in Patent Document 1, unnecessary rolling of the fiber at the time of applying the cosmetic can be prevented, and the adhesion between the fiber and the application surface can be improved because the cosmetic enters the fiber recess. And the beauty of the finish after application can be improved.

  In addition, in the foundation, in order to conceal undesired parts of the skin such as stains and make them look beautiful for viewing, development of high powders made of concealment is desired, and materials such as fine particle titanium dioxide have been developed. I came. On the other hand, the loss of bare skin feeling due to such high concealment is cited as the next issue to be developed.

  In the irregular cross-section fiber described in Patent Document 1, the fiber was uniformly dispersed in the cosmetic, and the adhesion between the fiber and the cosmetic when applying the cosmetic and the coated surface could be improved. It was difficult to give a feeling.

  Patent Document 2 proposes a cosmetic containing a modified cross-section fiber having a well-shaped cross section. According to the cosmetics described in Patent Document 2, by including well-shaped cross-section fibers and particles of a specific compound, it is excellent in the effect of diffusing and reflecting the light irradiated on the application site, and increases the brightness of the light irradiation site. Can enhance the impression of vivid expression and youthfulness.

  However, the cosmetic disclosed in Patent Document 2 uses irregular cross-section fibers having a well-shaped cross section, so that there are many straight portions in the fibers, and a foreign object sensation occurs when applied to the skin, resulting in a smooth feeling of use. It wasn't something that could be done.

Further, cosmetics such as mascara contain fibers in order to obtain a long lash effect that makes eyelashes look longer and an effect that makes eyelashes volume up. Such cosmetics are also required to have a smooth feeling of use, a feeling of gloss and volume after application, and a beautiful finish, but none satisfying all the requirements has been obtained.
JP 2004-107237 A JP 2006-52202 A

  The present invention solves the above problems, and when applied in cosmetics, the present invention is excellent in light diffusion and reflection, can provide a glossy bare skin feeling, and has no foreign body feeling. To provide a modified cross-section fiber that has a smooth feeling of use and can also have a volume-up effect when used in mascara and the like, and to provide a makeup cosmetic containing such a modified cross-section fiber. This is a technical issue.

The inventors of the present invention have arrived at the present invention as a result of studies to solve the above problems.
That is, the gist of the present invention is the following (1) and (2).
(1) A cross-sectional shape of a single yarn cut perpendicular to the fiber axis direction is a modified cross-section fiber having a shape in which two circular shapes having openings are connected at least at one point, and the two circular shapes The openings are connected without blocking, the maximum length connecting any two points in the cross-sectional shape is 1.1 times or more of the circular diameter having the maximum diameter, and the maximum length is 5 to 100 μm, two An irregularly shaped cross-section fiber having an opening angle of 30 to 140 ° and a single yarn fineness of 1.0 to 7.0 dtex.
(2) A makeup cosmetic containing the modified cross-section fiber according to (1).

  The irregular cross-section fiber of the present invention has a cross-sectional shape of a single yarn in which two circular shapes having openings are connected at at least one point, and is a shape composed of a curved portion. It has an excellent diffusion and reflection effect, and a soft gloss without glare. For this reason, when it is made to contain in cosmetics and apply | coating, the glossy bare skin feeling can be obtained. And since a cross-sectional shape does not have a linear part, when it apply | coats to bare skin, it has a smooth feeling of use without a foreign material feeling, and the beauty of a finish is also acquired. Furthermore, since the cross-sectional shape is a shape in which two circles are connected, it is bulky, and when used in a mascara or the like, a volume-up effect can be achieved.

  Since the makeup cosmetic of the present invention contains the modified cross-section fiber of the present invention, it is possible to obtain a glossy feeling of the skin, and when applied to the bare skin, there is no sense of foreign matter and a smooth feeling of use. It becomes the foundation which has. Moreover, since the modified cross-section fiber of the present invention has bulkiness, the makeup cosmetic of the present invention can be a mascara having an excellent volume-up effect.

The present invention is described in detail below.
The irregular cross-section fiber of the present invention has a cross-sectional shape of a single yarn that will be described in detail below, and may be either a multifilament or a monofilament.

  And it is suitable to use the modified cross-section fiber of the present invention in cosmetics. As cosmetics, makeup cosmetics are preferable, and among them, foundation, mascara, eyebrow and the like are preferable.

  The modified cross-section fiber of the present invention has a cross-sectional shape obtained by cutting a single yarn perpendicular to the fiber axis direction, and two circular shapes having openings are connected at least at one point, and the two circular openings Are connected without blocking.

  The circular shape having the opening is a C-shaped shape, and two C-shaped ones are connected to each other, and the connecting part is one or more points. Among them, those having two connecting portions are preferable.

  As an embodiment of the cross-sectional shape of the single yarn of the odd-shaped cross-section fiber of the present invention, those having the shapes of (A) to (F) in FIG. (A), (B), (D), and (F) have two connecting portions, and (C) and (E) have one connecting portion.

  In the connected shape, the two circular openings are connected without being closed. That is, as shown in FIG. 2, when the opening ends are connected, the opening is closed.

  The irregular cross-section fiber of the present invention is a shape as shown in FIG. 1, so that it becomes a complicated shape consisting of only a curved portion and becomes bulky, and at the same time, not only the outer peripheral surface of the shape, but also the end of the opening, Even in the inside of the opening, the portion where the irradiated light is reflected increases, and the light diffusion and reflection action is excellent.

  And in the cross-sectional shape of the irregular cross-section fiber of the present invention, it does not have a straight portion, it consists only of a curved portion, and light is reflected and diffused at the curved portion, so that a glare feeling does not occur and is soft. Light diffusion and reflection can be obtained, and when it is contained in a foundation or the like, it has a natural skin feeling as well as a glossy feeling.

  The shape as shown in FIG. 2 is bulky, but the portion that reflects the irradiated light is only the outer peripheral surface, which is inferior in light diffusion and reflection action, and is glossy and natural. I cannot get a feeling of bare skin.

  Furthermore, the irregular cross-section fiber of the present invention has a shape composed of a curved portion in which two circular shapes are combined, and does not have a straight portion. It becomes a feeling of use, and the beauty of the finish is also obtained.

  In addition, since it is a shape that consists only of curved parts combined with a circle, there are not many fibers in contact with the bare skin even when applied to the bare skin, so there is no adhesion and no concealment, so it is natural. A feeling of bare skin can be obtained.

  And the opening angle of two circular is 30-140 degrees, and 50-120 degrees is especially preferable. The opening angle in the present invention means an angle θ formed by a line drawn from a circular center point O toward two opening end portions M and N, as shown in FIG.

  When the opening angle is less than 30 °, it is impossible to obtain the light reflection and diffusion actions as described above, and when it is contained in the foundation, it is not possible to obtain a glossy feeling or a natural skin feeling. On the other hand, when the opening angle exceeds 140 °, the opening becomes too wide, so that a foreign material sensation occurs when the cosmetic containing this fiber is applied to the bare skin.

  Further, in the cross-sectional shape of the irregular cross-section fiber of the present invention, even if the two circular sizes are equal as shown in FIGS. 1 (A) to 1 (D), FIGS. The size of the two circles may be different as shown in FIG. The direction in which the two openings are opened is not particularly limited as long as the opening is not blocked.

  In the cross-sectional shape of the irregular cross-section fiber of the present invention, it is preferable that the shape in which two circles are connected is line symmetric or point symmetric. If it is line symmetric or point symmetric, it becomes a balanced cross-sectional shape, it becomes possible to make light reflection and diffusion more balanced and soft, and the dispersion in cosmetics becomes more uniform, The feeling of foreign matter is reduced, and the feeling of use and finish are also good.

  Further, in the modified cross-section fiber of the present invention, in the cross-sectional shape in which two circles are connected, the maximum length L connecting any two points is larger than the diameter of the circle having the maximum diameter R, and the maximum length L is 5 to 100 μm. It is.

  That is, in the present invention, in order to have bulkiness, the maximum length L connecting any two points is 1.1 times or more (L ≧ 1.1R) of the circular diameter having the maximum diameter R. And In the cross-sectional shape as shown in FIG. 4, the maximum length L is the same as the circular diameter having the maximum diameter R (L = R), and the bulkiness is poor. In consideration of bulkiness, light reflection and diffusion effects, the maximum length L is preferably 1.2 times or more, and more preferably 1.3 times or more the diameter of a circle having the maximum diameter R.

  And the maximum length L is 5-100 micrometers, and it is preferable that it is 20-80 micrometers especially. Furthermore, the single yarn fineness is preferably 1.0 to 7.0 dtex, and more preferably 2.0 to 6.0 dtex.

  By setting the size of the cross-sectional shape within such a range, the above-described bulkiness, light reflection and diffusion effects can be improved. When the maximum length is less than 5 μm or the single yarn fineness is less than 1.0 dtex, these effects are poor. On the other hand, when the maximum length exceeds 100 μm or the single yarn fineness exceeds 7.0 dtex, When applied to the bare skin, it has a foreign body feel.

  Further, the irregular cross-section fiber of the present invention has a bulkiness due to the shape as described above, and when it is contained in mascara, a long lash effect and a volume-up effect can be obtained.

  The deformed cross-section fiber of the present invention is preferably obtained by melt spinning using a thermoplastic resin from the viewpoint of moldability of a single yarn cross-sectional shape. That is, the irregular cross-section fiber of the present invention is preferably obtained by melt spinning a thermoplastic resin using a spinneret having a spinning hole (slit) perforated so as to obtain a desired cross-sectional shape.

  Examples of the thermoplastic resin include polyamide, polyester, polyurethane, and polyolefin. Among them, it is preferable to use polyamide because the skin irritation becomes soft.

  Further, in these thermoplastic resins, as long as the effects of the present invention are not impaired, a thermal stabilizer, a crystal nucleating agent, a matting agent, a pigment, a weathering agent, a light-proofing agent, a lubricant, an oxidation agent, and the like, if necessary. Inhibitors, antibacterial agents, fragrances, plasticizers, dyes, surfactants, flame retardants, surface modifiers, various inorganic and organic electrolytes, and other similar additives can be added.

  The length of the fiber when the modified cross-section fiber of the present invention is contained in the makeup cosmetic is preferably 20 to 1000 μm, and more preferably 100 to 500 μm.

  When the fiber length is shorter than 20 μm, the light diffusion, reflection effect and volume increase effect tend to be insufficient. On the other hand, when the fiber length is longer than 1000 μm, a feeling of foreign matter is felt at the time of application, and the finished product tends to be inferior.

  And the makeup cosmetics of this invention contain the unusual cross-section fiber of this invention. As makeup cosmetics, among them, foundation, mascara, eyebrow and the like are preferable.

  These makeup cosmetics preferably contain 0.1 to 15% by mass of the irregular cross-section fiber of the present invention, and more preferably 1 to 10% by mass.

  When the content of the modified cross-section fiber of the present invention in the makeup cosmetic of the present invention is less than 0.1% by mass, the light diffusion, reflection effect and volume increase effect tend to be insufficient. On the other hand, when the content of the modified cross-section fiber of the present invention is more than 15% by mass, a feeling of foreign matter is felt at the time of application, and the finished product tends to be inferior.

Next, the manufacturing method of the irregular cross-section fiber of this invention is demonstrated using an example.
Nylon 6 is used as a thermoplastic resin, and melt spinning is performed at 256 ° C. using a spinneret having a spinning hole drilled so as to obtain a desired cross-sectional shape using a normal extruder-type melt spinning apparatus. After the spun yarn is cooled and solidified, it is stretched without being wound or wound once, and a modified cross-section fiber is obtained by winding while performing a heat treatment at the time of stretching as necessary. And when making the obtained irregular cross-section fiber contain in cosmetics, it cuts into desired fiber length using a guillotine cutter etc., and uses it.

  In addition, although the makeup cosmetics of this invention contain the unusual cross-section fiber of this invention, in a foundation, a mascara, an eyebrow etc., it is preferable to make it contain, mixing with a mixer.

Next, the present invention will be specifically described with reference to examples. In addition, measurement and evaluation of various values in the examples were performed as follows.
[Aperture angle, maximum length, circular diameter]
A microphotograph photographing apparatus was attached to a Nikon Microphoto S optical microscope, and the cross-sectional shape of the single yarn was photographed for 24 single yarns, and the length and angle of each were measured, and the average value of the 24 yarns was obtained.
[Light reflection, diffusion effect]
Using the obtained foundation, the same model was made up and photographed, and five professional panelists evaluated it according to the following four levels.
◎ ・ ・ ・ Excellent gloss and feel.
○ ... Excellent gloss and skin feel.
Δ: Slightly excellent in feeling of gloss and bare skin.
X: Inferior to glossiness and bare skin feeling.
[Use feeling]
The obtained foundation or mascara was used to make up a model of 10 persons, and the presence or absence of a foreign object feeling during coating was evaluated in the following three stages.
◎ ・ ・ ・ No more foreigners but more than 9 people.
○ 7-7 people do not feel a foreign body feeling.
Δ: No sense of foreign body, but 4 to 6 persons.
X: No foreign body feeling but 3 or fewer.
[Volume up feeling]
Using the obtained mascara, 10 models were made up and evaluated for the presence or absence of volume up after makeup in the following three stages.
◎ ・ ・ ・ I feel a sense of volume up, but more than 9 people.
○ 7-7 people feel volume up.
Δ: 4-6 people feel volume up.
× ・ ・ ・ I feel a sense of volume up, but no more than 3 people.

Example 1
A master chip was prepared by adding 20% by mass of Red No. 205 as a pigment to polyamide 6 having a relative viscosity (measured at 96% sulfuric acid as a solvent, concentration of 1 g / dl, temperature of 25 ° C.) 3.50. .
This master chip and nylon 6 having a relative viscosity of 3.50 are mixed at a mass ratio of 1:39 (so that the content of red No. 203 in the fiber is 0.5% by mass), and a normal extruder melt spinning is performed. The apparatus was used for melt spinning. At this time, melt spinning was performed at 256 ° C. using a spinneret having a slit perforated so that the cross-sectional shape of the single yarn became the shape shown in FIG. After spinning and solidifying the spun yarn, the surface speed of the first roller (temperature 25 ° C.) is 3111 m / min, the surface speed of the second roller (temperature 110 ° C.) is 4200 m / min, and the draw ratio is 1. The film was stretched 35 times and wound at a speed of 4000 m / min to obtain a 60 dtex / 24f multifilament. The cross-sectional shape of the obtained multifilament single yarn is as shown in FIG. 1C (the two circles have the same size and the same opening angle), and have one connecting point and two circular opening angles. Was 50 °, the maximum length was 25 μm, the circular diameter having the maximum diameter was 20 μm, and the single yarn fineness was 2.5 dtex.
And it cut using the guillotine cutter, it was set as the short fiber (component A) of fiber length 400 micrometers, and the foundation which consists of a component and content shown to the following prescription 1 was produced. At this time, after mixing the component B with a Henschel mixer, pulverizing with a pulverizer equipped with a 0.9 mm round hole screen, then adding the component A, mixing with the Henschel mixer, and further mixing the component C with the Henschel mixer. Coating was performed by spraying to obtain a foundation.

[Prescription 1]
Component A: Nylon 6 short fiber 5% by mass
Component B: Silicone baking treatment Titanium dioxide 20% by mass
Silicone-baked yellow iron oxide 5% by mass
Silicone baked bengara 0.5% by mass
Silicone baked ultramarine 0.1% by mass
Sericite 30% by mass
Mica 19.4% by mass
Silica 10% by mass
Component C: Dimethicone 5% by mass
Octyldodecyl oleate 5% by mass

Examples 2-6, Comparative Examples 1-4
Except for changing the slit shape of the spinneret so that the opening angle, the maximum length, the circular diameter having the maximum diameter, and the single yarn fineness in the cross-sectional shape of the single yarn are as shown in Table 1. In the same manner as in No. 1, multifilaments were obtained and made into short fibers, and then a foundation was obtained according to Formula 1.

Example 7
A multifilament was obtained in the same manner as in Example 1, except that a spinneret having a slit perforated so that the cross-sectional shape of the single yarn became the shape shown in FIG. At this time, the cross-sectional shape of the obtained multifilament single yarn is as shown in FIG. 1A (the two circles have the same size and the same opening angle), and there are two connecting portions and two circles. The opening angle was 50 °, the maximum length was 30 μm, the circular diameter having the maximum diameter was 20 μm, and the single yarn fineness was 2.5 dtex. And it was made into the short fiber like Example 1, and the foundation was obtained by the prescription 1.

Examples 8-12, Comparative Examples 5-8
Except for changing the slit shape of the spinneret so that the opening angle, the maximum length, the circular diameter having the maximum diameter, and the single yarn fineness in the cross-sectional shape of the single yarn are as shown in Table 1. In the same manner as in No. 7, multifilaments were obtained and made into short fibers.

Comparative Example 9
A multifilament was obtained in the same manner as in Example 1 except that a spinneret was used in which slits were perforated so that the single yarn had a circular C-shaped cross-section with an opening. At this time, the cross-sectional shape of the obtained multifilament single yarn was C type, the opening angle was 90 °, the maximum length (diameter) was 25 μm, and the single yarn fineness was 2.5 dtex. And it was made into the short fiber like Example 1, and the foundation was obtained by the prescription 1.

Comparative Example 10
A multifilament was obtained in the same manner as in Example 1 except that a spinneret with a slit perforated so that the cross-sectional shape of the single yarn had a well-shaped cross-sectional shape was used. At this time, the cross-sectional shape of the obtained multifilament single yarn was a well-shaped one, the maximum length was 40 μm, and the single yarn fineness was 2.5 dtex. And it was made into the short fiber like Example 1, and the foundation was obtained by the prescription 1.

Reference example 1
The foundation which consists of a component and content shown to the following prescription 2 without producing a fiber was produced.
[Prescription 2]
Component A: Nylon 6 short fiber 0% by mass
Component B: Silicone baking treatment Titanium dioxide 20% by mass
Silicone-baked yellow iron oxide 5% by mass
Silicone baked bengara 0.5% by mass
Silicone baked ultramarine 0.1% by mass
Sericite 30% by mass
Mica 24.4% by mass
Silica 10% by mass
Component C: Dimethicone 5% by mass
Octyldodecyl oleate 5% by mass

  Table 1 shows the evaluation results of the modified cross-section fibers and foundations obtained in Examples 1 to 12, Comparative Examples 1 to 10, and Reference Example 1.

As is clear from Table 1, the modified cross-section fibers of Examples 1 to 12 were those in which the cross-sectional shape of the single yarn satisfied the shape of the present invention. It was excellent in the reflection and diffusion effects of the film, was able to obtain a good gloss and a natural feeling of the skin, had no feeling of foreign matters during application, and had a smooth feeling of use.
On the other hand, the irregular cross-section fibers of Comparative Examples 1 and 5 had an opening angle of 150 °. Therefore, the foundation containing these irregular cross-section fibers has a light reflecting and diffusing effect, but feels a foreign object feeling during coating. It was. Since the irregular cross-section fibers of Comparative Examples 2 and 6 had an opening angle of 20 °, the foundation containing these irregular cross-section fibers did not feel a foreign object feeling at the time of application, but had a light reflection and diffusion effect. It was insufficient, and a good gloss and natural skin feeling could not be obtained. Since the maximum length of the irregular cross-section fibers of Comparative Examples 3 and 7 was too large, the monofilament fineness of the irregular cross-section fibers of Comparative Examples 4 and 8 was too large. Therefore, any foundation containing these irregular cross-section fibers was applied. Sometimes a foreign body sensation was felt. Further, since the irregular cross-section fiber of Comparative Example 9 was a C-type, the light reflection and diffusion effects were insufficient, and the foundation containing this irregular cross-section fiber had good gloss and natural skin feeling. Couldn't get. Since the modified cross-section fiber of Comparative Example 10 was a well-shaped fiber, a soft light reflection and diffusion effect could not be obtained, and the foundation containing this modified cross-section fiber had a glare feeling and a good gloss feeling. I could not get a natural skin feeling. Furthermore, a foreign material sensation was felt during application.

Example 13
Polyamide 6 having a relative viscosity of 3.50 was melt-spun using an ordinary extruder-type melt spinning apparatus. At this time, melt spinning was performed at 256 ° C. using a spinneret having a slit perforated so that the cross-sectional shape of the single yarn became the shape shown in FIG. After spinning and solidifying the spun yarn, the surface speed of the first roller (temperature 25 ° C.) is 3111 m / min, the surface speed of the second roller (temperature 110 ° C.) is 4200 m / min, and the draw ratio is 1. The film was stretched 35 times and wound at a speed of 4000 m / min to obtain a 60 dtex / 24f multifilament. The cross-sectional shape of the obtained multifilament single yarn is as shown in FIG. 1C (the two circles have the same size and the same opening angle), and have one connecting point and two circular opening angles. Was 50 °, the maximum length was 25 μm, the circular diameter having the maximum diameter was 20 μm, and the single yarn fineness was 2.5 dtex.
And it cut using the guillotine cutter, it was set as the short fiber (component D) of fiber length 1000 micrometers, and the mascara which consists of the component E and content shown to the following prescription 3 was obtained.

[Prescription 3]
Component D: Nylon 6 short fiber 5.0 mass%
Component E: Polyacrylic ester emulsion 50.0% by mass
Polymethacrylic acid 2.0% by mass
Triethanolamine 2.5% by mass
Butylene glycol 3.0% by mass
Sodium chloride 0.5% by mass
Preservative 0.2% by mass
Silica 2.0% by mass
Pigment 1.0% by mass
Fragrance 0.1% by mass
Purified water 33.7% by mass

Examples 14-18, Comparative Examples 11-13
Examples except that the opening angle, the maximum length, the circular diameter having the maximum diameter, and the single yarn fineness in the cross-sectional shape of the single yarn are changed to those shown in Table 2 by changing the slit shape of the spinneret. A multifilament was obtained in the same manner as in No. 13 to make a short fiber, and then a mascara was obtained according to formulation 3.

Comparative Example 14
A multifilament was obtained in the same manner as in Example 13 except that a spinneret was used in which a slit was perforated so that the cross-sectional shape of the single yarn was a single C-shaped cross-section with an opening. At this time, the cross-sectional shape of the obtained multifilament single yarn was C type, the opening angle was 90 °, the maximum length (diameter) was 25 μm, and the single yarn fineness was 2.5 dtex. And after making it a short fiber like Example 13, the mascara was obtained by the prescription 3.

Comparative Example 15
A multifilament was obtained in the same manner as in Example 13, except that a spinneret having a slit perforated so that the cross-sectional shape of the single yarn had a well-shaped cross-sectional shape was used. At this time, the cross-sectional shape of the obtained multifilament single yarn was a well-shaped one, the maximum length was 40 μm, and the single yarn fineness was 2.5 dtex. And after making it a short fiber like Example 13, the mascara was obtained by the prescription 3.

As is apparent from Table 2, the modified cross-section fibers of Examples 13 to 18 had a cross-sectional shape of a single yarn satisfying the shape of the present invention, so that the mascara containing these modified cross-section fibers was a volume. It was excellent in the up effect, had no foreign material feeling during application, and had a smooth use feeling.
On the other hand, since the irregular cross-section fiber of Comparative Example 11 had an opening angle of 150 °, the mascara containing the irregular cross-section fiber felt a foreign body feeling during application. Since the irregular cross-section fiber of Comparative Example 12 has a maximum length that is too large, the irregular cross-section fiber of Comparative Example 13 has a single yarn fineness that is too large. It was Moreover, since the irregular cross-section fiber of Comparative Example 14 was a C-type, the mascara containing the irregular cross-section fiber had an insufficient volume-up effect. Since the irregular cross-section fiber of Comparative Example 15 was a well-shaped fiber, the mascara containing the irregular cross-section fiber had an insufficient volume-up effect and felt a foreign object feeling.

It is a schematic diagram which shows the embodiment of the cross-sectional shape of the single yarn of the irregular cross-section fiber of this invention. It is a schematic diagram which shows the embodiment of the cross-sectional shape of the single yarn of the irregular cross-section fiber other than this invention. It is explanatory drawing which shows the opening angle of the irregular cross-section fiber of this invention. It is a schematic diagram which shows the embodiment of the cross-sectional shape of the single yarn of the irregular cross-section fiber other than this invention.

Claims (2)

The cross-sectional shape of a single yarn cut perpendicular to the fiber axis direction is a modified cross-section fiber having a shape in which two circular shapes having openings are connected at least at one point, and the two circular openings are It is connected without closing, the maximum length connecting any two points in the cross-sectional shape is 1.1 times or more of the circular diameter having the maximum diameter, and the maximum length is 5 to 100 μm. An irregular cross-section fiber having an opening angle of 30 to 140 ° and a single yarn fineness of 1.0 to 7.0 dtex. A makeup cosmetic containing the modified cross-section fiber according to claim 1.