WO2017119341A1

WO2017119341A1 - Brush bristle material, and brush using same

Info

Publication number: WO2017119341A1
Application number: PCT/JP2016/088720
Authority: WO
Inventors: 山本健雄; 土岐美鈴; 柴田剛志; 増田正人; 松浦知彦
Original assignee: 東レ・モノフィラメント株式会社; 東レ株式会社
Priority date: 2016-01-07
Filing date: 2016-12-26
Publication date: 2017-07-13
Also published as: JP6849190B2; CN108495577B; JPWO2017119341A1; KR20180100148A; CN108495577A; TWI731019B; TW201735832A

Abstract

Provided is a brush bristle material characterized in that, at one end or both ends in the lengthwise direction of a composite fiber having a core-in-sheath cross-sectional structure comprising a plurality of resin layers formed from at least two types of resin having different drug dissolution rates, at least one circular wall, which extends in the lengthwise direction of the composite fiber and extends across the entire periphery in the direction along the outer peripheral surface of the composite fiber, and at least one groove, which extends along the circular wall adjacent to the circular wall on the inner side thereof and is recessed in the lengthwise direction of the composite fiber from the tip of the circular wall, are formed. Further provided is a brush using the brush bristle material. As a result of the circular wall formed at the tip of the bristle material and the groove formed on the inner side of the circular wall, it is possible to provide: a brush bristle material that demonstrates a high cleaning performance including both an excellent dirt-scraping ability and an excellent dirt-trapping ability; and a brush using the brush bristle material.

Description

Brush hair material and brush using the same

The present invention relates to a brush bristle material suitable for various brushes including a toothbrush and a brush using the same.

Conventionally, a technique using a monofilament of synthetic fiber as a hair material for a brush is widely known. In brushes using such brush bristle material, for example, toothbrushes, it is desired that the brush tip has an excellent cleaning effect, and furthermore, excellent scraping performance of dirt and plaque when cleaning with the tip. It is desirable to have

However, when the bristle material for the brush is formed of a monofilament made of a single material up to the hair tip, it may be difficult to satisfy such a requirement. In other words, if the tip is formed of a monofilament made of a single material up to the tip of the hair, the cleaning effect of the tip of the hair itself may be limited, and in particular, it is difficult to obtain excellent scraping performance of dirt and plaque due to the tip of the hair. There is a fear.

清掃 There are almost the same problems in brushes for cleaning and cleaning in other fields.

Therefore, in order to particularly improve the cleaning effect, in Patent Document 1, a bristle material made of a composite fiber having a core-sheath cross-sectional structure is formed into a multileaf cross-sectional shape having a plurality of concave portions and convex portions on the outer periphery, There is disclosed a bristle material for a toothbrush in which branched hairs composed of these convex portions are formed in a crown shape at the tip of the bristle material and a depression is formed in the central portion of the crown-shaped portion. Patent Document 2 discloses a structure of a bristle material for a brush in which a tip portion of a bristle material is formed into a tapered portion, and a plurality of grooves extending in the fiber axis direction are formed on the outer peripheral surface of the taper portion. Yes.

However, in the toothbrush bristle material disclosed in the above-mentioned Patent Document 1, the effect of scraping dirt is exhibited in the crown-shaped part, and the cleaning effect can be improved by that amount, but the crown-shaped part is formed. Since a dent is formed between the convex parts, even if dirt is once taken into the depression in the center of the crown-shaped part, the dirt easily escapes through the dent. The problem remains that it may adhere. Moreover, since the convex part which forms a crown-shaped part is formed in the intermittent convex part which protrudes from a hair-material front-end | tip, the waist | lumbar of each convex part is not so high, with respect to stains with high viscosity, etc. However, there remains a problem that the scraping effect may be lowered. Moreover, in the bristle material for brushes disclosed in Patent Document 2, since a plurality of grooves extending in the fiber axis direction are formed on the outer peripheral surface of the tapered portion, the dirt scraping performance (cleanability) is improved. Although the effect is recognized, it is not possible to expect the performance of capturing the dirt once scraped off, and further improvement is desired.

JP 2012-105743 A JP 2009-089920 A

Then, the subject of this invention pays attention to the remaining problem of the bristle material for brushes as described in the conventional patent document 1, and can improve the scraping performance of the stain | pollution | contamination in the hair tip part of bristle material more. Another object of the present invention is to provide a bristle material for a brush excellent in cleanability that can be satisfactorily captured without scraping off dirt once scraped, and a brush using the same.

In order to solve the above problems, the bristle material for a brush according to the present invention is a longitudinal direction of a composite fiber having a core-sheath cross-sectional structure composed of a plurality of resin layers formed of two or more types of resins having different drug dissolution rates. At least one annular wall that extends in the longitudinal direction of the conjugate fiber and extends along the outer peripheral surface of the conjugate fiber at one end or both ends, and the annular wall adjacent to the annular wall inside the annular wall At least one groove extending along the wall and recessed from the tip of the annular wall in the longitudinal direction of the composite fiber is formed.

In such a bristle material for brushes according to the present invention, one or both longitudinal ends of a composite fiber having a core-sheath cross-sectional structure composed of a plurality of resin layers formed of two or more types of resins having different drug dissolution rates In the part, a resin layer part having a low drug dissolution rate is appropriately left by using a drug dissolution process to form an annular wall, and a resin layer part having a high drug dissolution rate is appropriately dissolved therein to form a groove. Is formed. That is, in the bristle material for brushes according to the present invention, since at least one annular wall extending over the entire circumference in the direction along the outer peripheral surface of the conjugate fiber is formed at the tip of the conjugate fiber constituting the bristle material, The annular wall can exhibit a so-called edge effect when scraping off dirt, and can exhibit a high edge effect because the annular wall itself has a high waist due to the annular wall structure continuously extending over the entire circumference, and has a high viscosity. Excellent scraping performance against dirt. The dirt scraped off by the annular wall is taken into a groove formed inside thereof and is captured by the groove. Since the groove is surrounded by an annular wall extending from the outside to the entire circumference, the dirt trapped in the groove is not easily escaped beyond the annular wall portion, and is well within the groove. It remains in the captured state. Therefore, the hair tip portion provided with the annular wall and the groove inside thereof exhibits excellent cleaning properties.

In the brush bristle material according to the present invention, the number of the plurality of resin layers formed of two or more kinds of resins having different drug dissolution rates may be two or more, preferably 3 to 6 layers. It is in the range. The number of the annular wall and the number of grooves inside the annular wall may be at least one. Therefore, when the number of the plurality of resin layers is two, the radially outermost layer in the cross section of the conjugate fiber becomes a layer forming an annular wall, and the entire inner portion becomes a layer forming a groove.

Further, the depth of the groove formed inside the annular wall is not particularly limited, but is preferably 0.1 mm or more, more preferably 0.5 mm or more, and further preferably 1 mm or more. The depth of the groove may be set according to the use of the bristle material for the brush, and by setting the depth to a specific depth or more, high trapping performance can be exhibited even for high-viscosity dirt.

Further, the thickness of one resin layer in the cross section of the composite fiber is preferably in the range of 10 to 300 μm, more preferably in the range of 15 to 150 μm. Each resin layer is a part that forms the annular wall and the groove inside the annular wall at the end of the composite fiber, so as to ensure excellent dirt scraping performance by the annular wall and excellent dirt capturing performance by the groove. For this, the thickness of the resin layer is preferably set in the above range.

Further, in the bristle material for brushes according to the present invention, the diameter of the composite fiber is preferably in the range of 50 to 1,000 μm, more preferably in the range of 80 to 500 μm. When the diameter of the composite fiber is less than 50 μm, the waist of the composite fiber portion itself when used in a brush becomes too weak, and the cleaning effect may be lowered depending on the application. If the diameter of the composite fiber exceeds 1,000 μm, the composite fiber part itself becomes too stiff when used in a brush, and the root part of the tip part depends on the shape of the annular wall and groove on the tip part. There is a possibility that the composite fiber portion in the above will be strongly pressed against the object to be cleaned and the object to be cleaned will be easily damaged.

In the bristle material for brushes according to the present invention, the length in the longitudinal direction of the composite fiber of the portion having the annular wall and the groove is preferably in the range of 0.5 to 10 mm. This length affects the performance of the annular wall having the dirt scraping performance as described above and the groove having the dirt catching performance, and may be appropriately set from the above range depending on the application.

Moreover, in the bristle material for brushes according to the present invention, it has an opposing wall that faces the annular wall with the groove in between, and the longitudinal height of the composite fiber of the opposing wall is higher than the height of the annular wall. It is also possible to adopt a high structure. In other words, it is a saddle-like or telescope-like structure in which an opposing wall with a higher height is present on the inner diameter side of the annular wall with the groove therebetween. By adopting such a structure, the entire tip of the bristle material can be tapered to form a tapered shape, so that the hair can be scraped off by the annular wall as described above, and the dirt can be captured by the groove, while the hair is captured. A soft tactile sensation at the front can also be realized.

Moreover, in the bristle material for brushes according to the present invention, the extended shape of the at least one annular wall may take various shapes, a structure composed of an annular wall extending in a circular shape, and an annular shape extending in an irregular shape other than a circular shape Any of the wall structures can be used. As an annular wall extending in a circular shape, not only an annular wall extending in a substantially circular shape with substantially the same wall thickness, but also an annular wall extending in a wavy form, or an annular wall whose wall thickness changes in the extending direction Walls are also included. The annular wall extending in a deformed shape other than a circle includes an annular wall extending in the form of a triangle, a quadrangle, or more polygons, and any annular wall extending in a deformed shape other than a square.

Moreover, in the bristle material for brushes according to the present invention, the cross-sectional shape of the entire composite fiber may be either a circular shape or a non-circular cross-sectional shape. What is necessary is just to determine suitably according to a use, a use form, use conditions, etc.

In the bristle material for a brush according to the present invention, it is preferable that the plurality of resin layers constituting the composite fiber are provided concentrically. As long as it is concentric, either a concentric shape or a shape in which only one of the layers is formed in a polygon other than a circle or an irregular cross-sectional shape can be adopted. By providing the plurality of resin layers concentrically, the desired annular wall and groove in the present invention can be easily formed by the chemical dissolution treatment.

The present invention also provides a brush in which the brush hair material according to the present invention as described above is used at least in part. In particular, the brush according to the present invention has excellent dirt scraping performance due to the annular wall formed at the tip of the bristle material as described above and excellent dirt catching ability due to the groove, so that the toothbrush and tongue brush, It is suitable as a makeup brush, a brush for application, and the like.

In such a brush according to the present invention, although it depends on its use, a range of 1 to 50 mm is exemplified as a preferable range of bristle length (length from the brush root to the bristles), more preferably The range is 5 to 35 mm.

As described above, according to the present invention, the high cleaning that combines the excellent dirt scraping performance and the excellent dirt catching performance by the annular wall formed at the tip of the bristle material and the groove formed inside thereof. It is possible to provide a bristle material for a brush that exhibits the properties.

Further, according to the present invention, various brushes using at least a part of the brush bristle material as described above can be provided, and in particular, a brush suitable as a toothbrush, tongue brush, makeup brush, application brush or the like is provided. Can do.

1 shows a bristle material for a brush according to an embodiment of the present invention, FIG. 1 (A) is a schematic longitudinal sectional view of one end of the bristle material, and FIG. 1 (B) is a BB line in FIG. 1 (A). FIG. It is a schematic block diagram which shows the flocking method at the time of using the bristle material for brushes for a toothbrush. It is a schematic longitudinal cross-sectional view of the one end part of the bristle material for brushes concerning another embodiment of this invention. It is a schematic cross-sectional view which shows the various form examples of the bristle material for brushes concerning this invention. It is a schematic cross-sectional view which shows another various form example of the bristle material for brushes concerning this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows a bristle material 1 for a brush according to an embodiment (Embodiment 1) of the present invention, and FIG. 1 (A) shows one end of the bristle material 1. As shown in FIG. 1 (B), the brush bristle material 1 includes a plurality of

resin layers

2a, 2b, 2c formed of two or more types of resins (two types of resins in the illustrated example) having different drug dissolution rates. 2d, in particular in the present embodiment, is formed from a composite fiber 3 having a core-sheath cross-sectional structure composed of a plurality of

resin layers

2a, 2b, 2c, and 2d arranged concentrically with the same thickness in the extending direction. At one end or both ends in the longitudinal direction of the composite fiber 3 (FIG. 1 (A) shows only one end of the bristle material 1), it extends in the longitudinal direction of the composite fiber 3 and the outer peripheral surface of the composite fiber 3 At least one annular wall 4 extending over the entire circumference in a direction along the annular wall 4 and extending along the annular wall 4 adjacent to the annular wall 4 inside the annular wall 4 from the tip of the annular wall 4. At least one groove 5 recessed in the longitudinal direction is formed. In the present embodiment, the annular wall 4 is formed into a circular annular wall extending with the same thickness in the extending direction, and the groove 5 has an annular shape extending along the annular wall 4 with the same width inside the annular wall 4. It is formed in the groove. The annular wall 4 is formed of a resin layer 2c that is appropriately left undissolved in the drug dissolution process, and the inner groove 5 is formed by appropriately dissolving the resin layer 2b in the drug dissolution process. It is formed as a formed annular space. In this embodiment, at one end of the hair material 1, the resin layer 2a forms a cylindrical wall 6 that is appropriately left undissolved in the drug dissolution treatment, and the resin layer 2d is dissolved in the drug. An annular space 7 is formed by being appropriately dissolved in the treatment.

As the drug dissolution treatment, for example, alkali treatment can be applied, and as a plurality of resin layers formed of two or more kinds of resins having different drug dissolution rates (for example, dissolution rates by alkali treatment), for example, resin layer 2a 2c is formed of nylon (Ny) (registered trademark) as a resin that is not dissolved in an alkali, and

resin layers

2b and 2d are formed of polybutylene terephthalate (PBT) as a polyester-based resin that is dissolved in an alkali. By subjecting the longitudinal end portion of the conjugate fiber 3 to a predetermined length by alkali treatment and dissolving only the resin layers 2b and 2d at the end portion, as shown in FIG. The edge part of the bristle material 1 for brushes having the columnar wall 6 and the annular space 7 is formed.

In this bristle material 1 for brushes, at one end or both ends in the longitudinal direction of the composite fiber 3 having a core-sheath cross-sectional structure composed of a plurality of resin layers formed of two or more types of resins having different drug dissolution rates, Using the dissolution treatment, the resin layer 2c portion having a slow drug dissolution rate (formed from a resin layer that is not dissolved in alkali in the above embodiment) is left to form the annular wall 4, and the drug dissolution is performed on the inside thereof. The groove 5 is formed by appropriately dissolving the resin layer 2b portion having a high speed. Since the annular wall 4 is formed in an annular wall extending continuously around the entire circumference in an annular shape, the annular wall 4 can exhibit a high edge effect when scraping off dirt, and is excellent against dirt with high viscosity. Scraping performance can be expressed. The dirt scraped off by the annular wall 4 is taken in and captured by the groove 5 formed on the inside thereof, and the groove 5 is surrounded by the annular wall 4 extending over the entire circumference from the outside. Because of the structure, the dirt trapped in the groove 5 does not easily escape and is maintained in a state of being well trapped in the groove 5. Therefore, the tip part provided with these annular walls 4 and the groove | channel 5 inside it will express the outstanding cleaning property.

The brush bristle material 1 configured as described above is used at least in part for the production of various brushes. In general, as a method for flocking a brush bristle material on a brush component, two types of methods are typically known, but these two types of methods are illustrated with reference to the case of use in a toothbrush as an example. This will be described with reference to FIG.

FIG. 2 (A) shows a toothbrush 13 in which the brush bristle material 11 is planted on the head part of the toothbrush constituting member 12. As a method for planting the brush bristle material 11, FIG. 2 (A) a- There are two types of methods as shown in FIGS. 2B and 2C which are enlarged cross-sectional views along the a line. In the method shown in FIG. 2 (B), the brush bristle material 11 folded in half is inserted into the flock hole 14 and the brush bristle material 11 is fixed to the toothbrush component 12 with a fixture called a flat wire 15. . The completed toothbrush is usually called a flat wire toothbrush. In such a flat toothbrush, both ends of the brush bristle material 11 prepared in advance are the bristles of the brush. In the method shown in FIG. 2 (C), one end portion of the brush bristle material 11 is inserted into the through hole 16 of the head surface side member 12a of the toothbrush constituting member 12, and the end portion of the brush bristle material 11 thus inserted is inserted. A heating device (not shown) is applied to form a lump for preventing or fixing called a roasted ball 17, and after that, the head portion back side member 12b is joined to conceal the roasted ball 17 to complete a toothbrush product. Let The completed toothbrush is usually called a flat wire toothbrush. In such a flat wire toothbrush, one end of the brush bristle material 11 prepared in advance serves as a brush tip. Therefore, when the bristle material 1 for brushes according to the present invention is used for a flat toothbrush, the annular wall 4 and the groove 5 inside thereof are formed at both ends of the bristle material 1 for brushes. When used for a flat wire toothbrush, the annular wall 4 and the groove 5 are formed at one end of the brush bristle material 1.

FIG. 3 shows one end portion of a brush bristle material 21 according to another embodiment (Embodiment 2) of the present invention. In the present embodiment, the brush bristle material 21 is a plurality of

resin layers

22a and 22b formed of two or more kinds of resins (two kinds of resins in the illustrated example) arranged concentrically and having different drug dissolution rates. , 22c, 22d, and is formed from a composite fiber 23 having a core-sheath cross-sectional structure. At one end or both ends in the longitudinal direction of the composite fiber 23 (FIG. 3 shows only one end of the bristle material 21), it extends in the longitudinal direction of the composite fiber 23 and extends along the outer peripheral surface of the composite fiber 23. At least one annular wall 24 extending over the entire circumference, extending along the annular wall 24 adjacent to the annular wall 24 inside the annular wall 24 and extending in the longitudinal direction of the composite fiber 23 from the tip of the annular wall 24 A recessed at least one annular groove 25 is formed. In the present embodiment, the resin layers 22a and 22c are made of, for example, a resin having a slower dissolution rate with respect to alkali as a dissolution agent (for example, polybutylene terephthalate (PBT)), and the resin layers 22b and 22d are For example, it is made of a resin (for example, polyethylene terephthalate (PET)), which has a higher dissolution rate with respect to an alkali as a dissolving drug, and is cyclically formed by a resin layer 22c which is appropriately left undissolved in the drug dissolving process As the wall 24 is appropriately dissolved in the resin layer 22b in the drug dissolution process, the groove 25 is formed as a facing wall higher than the annular wall 24 by the resin layer 22a appropriately left undissolved in the drug dissolution process. The cylindrical wall 26 in the center is formed into an annular space 27 by appropriately dissolving the resin layer 22d in the drug dissolution process. They are formed. The central cylindrical wall 26 and the annular wall 24 having a height lower than that of the central wall form a hook-like or telescope-like structure, and the entire distal end portion of the bristle material 21 is formed in a tapered shape. .

Also in the bristle material for brush 21 having such a tapered end and a tapered end, as in the first embodiment, excellent dirt scraping performance by the annular wall 24 and excellent dirt catching performance by the groove 25 are provided. Excellent cleaning properties are exhibited and the tip portion is formed in a tapered shape as compared with the above-described first embodiment, so that even a finer part (for example, between teeth) is excellently cleaned. It is possible to exert an effect.

Table 1 summarizes typical characteristics of Embodiment 1 and Embodiment 2 when applied to a toothbrush. In Embodiment 1, the annular wall is formed of a resin layer made of nylon (Ny) (registered trademark), and the groove is formed of a resin layer of polybutylene terephthalate (PBT). In Embodiment 2, the annular wall is made of polybutylene terephthalate. (PBT) was formed from a resin layer, and the grooves were formed from a polyethylene terephthalate (PET) resin layer, and each was formed by alkali treatment. The characteristics of the bristle material for brushes in Table 1 are shown as contrast characteristics with the bristle material for brushes that are usually formed from a single nylon nylon (registered trademark), which is a general single material. The dirt scraping effect and dirt trapping effect by the part are shown as contrast characteristics with the hair material described in Patent Document 1 described above. A circle in Table 1 indicates that the characteristic is equal to or higher than that of the object to be compared, and an ◎ indicates that it is significantly superior to the object to be compared.

The brush bristle material according to the present invention may take various forms other than the first and second embodiments. FIG. 4 and FIG. 5 illustrate various forms in the cross section of the composite fiber.

The brush bristle material 31 shown in FIG. 4 (A) is formed on a composite fiber 33 that is concentrically arranged and includes a central resin layer 32a, an outer resin layer 32b, and an outermost resin layer 32c. In addition, the resin layer 32 b is formed in the annular wall 34, and the central resin layer 32 a is formed in the groove 35 inside the annular wall 34. 4B includes a central resin layer 42a, an outer resin layer 42b, an outer resin layer 42c, and an outermost resin layer 42d arranged concentrically. In addition to being formed on the composite fiber 43, the resin layers 32 b and 42 d are formed on the annular walls 44, and the resin layers 42 a and 42 c are formed on the grooves 45 inside the respective annular walls 44. In the bristle material for brush 51 shown in FIG. 4C, a central resin layer 52a, an outer resin layer 52b, an outer resin layer 52c, an outer resin layer 52d, and the like are arranged concentrically. It is formed on a composite fiber 53 composed of an outer resin layer 52e and an outermost resin layer 52f, the resin layers 52c and 52e are respectively on the annular walls 54, and the resin layers 52b and 52d are on the inner sides of the respective annular walls 54. A central resin layer 52 a is formed on the central cylindrical wall 56 formed in the groove 55. The brush bristle material 61 shown in FIG. 4 (D) is formed on a composite fiber 63 that is concentrically arranged and includes a central resin layer 62a, an outer resin layer 62b, and an outermost resin layer 62c. In addition, the outermost resin layer 62 c is formed on the annular wall 64, the resin layer 62 b is formed on the groove 65 inside the annular wall 64, and the central resin layer 62 a is formed on the central cylindrical wall 66.

Further, in the brush bristle material 71 shown in FIG. 5 (A), it is formed on a composite fiber 73 that is concentrically arranged and is composed of a central resin layer 72a, an outer resin layer 72b, and an outermost resin layer 72c. However, the resin layer 72 b is formed in a triangular resin layer, the resin layer 72 b is formed in the annular wall 74, and the central resin layer 72 a is formed in the groove 75 inside the annular wall 74. . In the brush bristle material 81 shown in FIG. 5B, a central resin layer 82a, an outer resin layer 82b, an outer resin layer 82c, an outer resin layer 82d, the outermost resin layer 82d, which are arranged concentrically. It is formed on a composite fiber 83 made of an outer resin layer 82e, but the resin layers 82b and 82d are formed in a resin layer extending in a ring shape in a wave shape, and these resin layers 82b and 82d are respectively formed on the annular wall 84. Inner resin layers 82 a and 82 c are formed in the inner grooves 85 of the annular walls 84. In the brush bristle material 91 shown in FIG. 5C, a central resin layer 92a, an outer resin layer 92b, an outer resin layer 92c, an outer resin layer 92d, It is formed on the composite fiber 93 composed of the outer resin layer 92e, but the resin layers 92b and 92d are formed in a petal shape in which the resin layer thickness changes in the annular extending direction, and these

resin layers

92b, 92 d is formed in each annular wall 94, and

resin layers

92 a and 92 c inside thereof are formed in grooves 95 inside each annular wall 94. The brush bristle material 101 shown in FIG. 5 (D) is formed on a composite fiber 103 that is concentrically arranged and includes a central resin layer 102a, an outer resin layer 102b, and an outermost resin layer 102c. However, the cross-sectional shape of the composite fiber 103 and each of the

resin layers

102a, 102b, and 102c is formed in a hexagonal shape, the outermost resin layer 102c is on the annular wall 104, and the resin layer 102b is on the inner side of the annular wall 104. In the groove 105, a central resin layer 102 a is formed on the central cylindrical wall 106.

As described above, the composite fiber having a core-sheath cross-sectional structure composed of a plurality of resin layers in the present invention can take various cross-sectional forms, and can be optimally designed according to the application and intended use. is there.

Examples of the present invention will be described below.
Examples 1 to 11 and Comparative Example 1
[Production of brush hair]
As raw materials, polybutylene terephthalate (PBT, “Toraycon” (registered trademark) 1100SW manufactured by Toray Industries, Inc.), polyethylene terephthalate (PET, manufactured by Toray Industries, Inc., T755M), nylon 610 (Ny610, manufactured by Toray Industries, Inc., “Amilan” "(Registered trademark) CM2001), thermoplastic polyamide elastomer (Ny11-PTMG (polytetramethylene glycol)," Pebax "(registered trademark) 72R53) manufactured by Arkema, Inc., polybutylene naphthalate (PBN, manufactured by Toyobo, AE-500) ) Was prepared under the recommended conditions. The core-sheath cross-sectional structure consisting of a plurality of resin layers, with the core component, the resin type of the sheath component, the area ratio between the core component and the sheath component, the number of resin layers, and the thickness of the resin layer (representative values) as shown in Table 2. A bicomponent fiber with melt spinning was melt spun. The core component referred to here is a component of the resin layer disposed at the center in the fiber cross section, and the sheath component is a component of the resin layer disposed other than the center in the fiber cross section. The structure of the resin layer in the cross section of the fiber was a structure in which the core component, sheath component 1, (sheath component 2), core component,.

After the eluted fiber was cooled and solidified in water, it was stretched 4.5 times in 60 ° C warm water as the first step and 120 ° C in a dry atmosphere as the second step, and then relaxed heat set in a dry heat atmosphere To obtain a core-sheath composite fiber. Table 2 shows the configuration of the obtained core-sheath composite fiber.

The above fibers were bundled in a straight line with a bundle diameter of 45 mm and packaged, and then cut into a predetermined length. Next, the bundle of composite fibers was immersed in a heated caustic soda solution with both the cut end faces exposed, and both ends were dissolved and removed to form an annular wall. By changing the immersion time in the caustic soda solution, the longitudinal length of the portion having the annular wall and the groove was controlled. Table 2 shows the characteristics of the obtained brush hair material.

As Comparative Example 1, a PBT fiber was dipped in a caustic soda solution in the same manner as described above, and a bristle material for a brush having both ends tapered to a taper was produced.

[Production of toothbrush]
The brush bristle material obtained by the above method was set in a flat wire type flocking machine, a predetermined number (about 15 to 40) was picked, and folded into the flock hole of the toothbrush head along with the flat wire and driven. . As the toothbrush head, one having a flocked portion with a diameter of 1.5 mm and 8 rows and 4 columns was used. Table 2 shows the bristle length (mm) and the number of flocks (lines / hole) of the toothbrushes produced in Examples and Comparative Examples.

The following evaluation was performed about each obtained toothbrush, and the result shown in Table 2 was obtained.
[Cleanability evaluation]
An artificial plaque made by Nissin Co. was applied to the dentition model and dried for 5 minutes or more. A toothbrush containing water was pressed from the upper surface of the dentition model with a load of 230 g, and brushing was performed in a direction along the dentition at a stroke width of 70 mm and a stroke speed of 180 mm / sec. For the evaluation of the tooth surface, the upper part of the back tooth part of the dentition model was used, and for the evaluation between the teeth, the outer part of the front tooth part was used. Based on the remaining amount of dirt when brushed 20 times with a nylon bristle brush, the cleanability was calculated from the number of brushings up to the standard using the following formula.
Cleanability = 20 ÷ (number of brushes to reach standard)

[Hair opening durability evaluation]
A load of 230 g is applied vertically from the back side of the sliding surface to the toothbrush, and a hot water of 37 ° C. is dripped in a longitudinal direction of the toothbrush with a stroke width of 70 mm and a stroke speed of 180 mm / sec. The sliding movement was performed 1000 times, and the open ratio of the brush part was measured. The method for calculating the openness ratio was (BA) / A × 100%, where Amm is the width of the brush portion in the initial state and Bmm is the width after sliding.

[Hair splitting durability evaluation]
Under the same conditions as in the evaluation of the above-mentioned hair opening durability, tearing of the hair tips was observed every 50 brushing times, and the number of times that the hair material in which the hair broke was 5 was recorded.

[Evaluation of touch and foaming]
Twenty adults used a toothbrush for 30 days, asked for answers according to the following criteria, and the average score was used as an evaluation value.
Score Tactile Foaming 5 Very soft Very foaming 4 Soft Good foaming 3 Normal Neither 2 Hard foaming 1 Very hard Very foaming

The present invention can be applied to all brushes, and is particularly suitable for toothbrushes, tongue brushes, makeup brushes, application brushes, and the like.

1, 21

Brush hair material

2a, 2b, 2c, 2d, 22a, 22b, 22c,

22d Resin layer

3, 23

Composite fiber

4, 24

Annular wall

5, 25

Groove

6, 26

Cylindrical wall

7, 27 Annular space 11 Brush material 12 Toothbrush component 12a Head portion surface side member 12b Head portion back surface side member 13 Toothbrush 14 Flocking hole 15 Flat wire 16 Through hole 17 Grilled

balls

31, 41, 51, 61, 71, 81, 91, 101

Brush Hair material

32a, 32b, 32c, 42a, 42b, 42c, 42d, 52a, 52b, 52c, 52d, 52e, 52f, 62a, 62b, 62c, 72a, 72b, 72c, 82a, 82b, 82c, 82d,

82e

92a, 92b, 92c, 92d, 92e, 102a, 102b,

102c Resin layers

33, 43, 53, 63, 73, 83, 93, 1 3

composite fiber

34,44,54,64,74,84,94,104

annular wall

35,45,55,65,75,85,95,105 groove 56,66,106 cylindrical wall

Claims

Extending in the longitudinal direction of the composite fiber and extending in the longitudinal direction of the composite fiber at one or both longitudinal ends of the composite fiber having a core-sheath cross-sectional structure composed of a plurality of resin layers formed of two or more types of resins having different drug dissolution rates At least one annular wall extending over the entire circumference in a direction along the outer peripheral surface, and extending along the annular wall adjacent to the annular wall inside the annular wall and recessed in the longitudinal direction of the composite fiber from the tip of the annular wall A bristle material for a brush, wherein at least one groove is formed.
The brush bristle material according to claim 1, wherein the number of the plurality of resin layers is in the range of 3 to 6 layers.
The brush bristle material according to claim 1 or 2, wherein the thickness of one resin layer in the cross section of the composite fiber is in the range of 10 to 300 µm.
The brush bristle material according to any one of claims 1 to 3, wherein the length of the composite fiber in the longitudinal direction of the portion having the annular wall and the groove is in the range of 0.5 to 10 mm.
5. The opposed wall facing the annular wall with the groove in between, wherein the longitudinal height of the conjugate fiber of the opposed wall is higher than the height of the annular wall. Brush hair material.
The brush bristle material according to any one of claims 1 to 5, wherein the at least one annular wall comprises an annular wall extending in a circular shape.
The brush bristle material according to any one of claims 1 to 5, wherein the at least one annular wall comprises an annular wall extending in an irregular shape other than a circle.
The brush bristle material according to any one of claims 1 to 7, wherein the plurality of resin layers are provided concentrically.
A brush in which the bristle material for brush according to any one of claims 1 to 8 is used at least in part.