CN108495577B

CN108495577B - Brush bristle material and brush using same

Info

Publication number: CN108495577B
Application number: CN201680078138.0A
Authority: CN
Inventors: 山本健雄; 土岐美铃; 柴田刚志; 增田正人; 松浦知彦
Original assignee: Toray Monofilament Co Ltd
Current assignee: Toray Monofilament Co Ltd
Priority date: 2016-01-07
Filing date: 2016-12-26
Publication date: 2020-10-16
Anticipated expiration: 2036-12-26
Also published as: TWI731019B; KR20180100148A; CN108495577A; TW201735832A; WO2017119341A1; JPWO2017119341A1; JP6849190B2

Abstract

A brush hair material characterized by having a core-sheath cross-sectional structure, wherein at one or both ends in the longitudinal direction of a composite fiber having a plurality of resin layers comprising 2 or more resins having different chemical dissolution rates, there are formed: at least one annular wall extending in the longitudinal direction of the composite fiber and extending over the entire circumference in a direction along the outer circumferential surface of the composite fiber, and at least one groove adjacent to the annular wall on the inside of the annular wall so as to extend along the annular wall and recessed from the leading end of the annular wall in the longitudinal direction of the composite fiber; and a brush using the same. A brush hair material capable of exhibiting high cleaning performance in which both excellent dirt sweeping performance and excellent dirt catching performance are exhibited by an annular wall formed at a front end portion of the hair material and a groove formed inside the annular wall; and a brush using the same.

Description

Brush bristle material and brush using same

Technical Field

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

Background

Conventionally, a technique of using synthetic fiber monofilaments as a brush bristle material has been widely known. In a brush, for example, a toothbrush, using such a brush bristle material, it is desired that the cleaning effect by the bristle tips is excellent, and further, it is desired that the brush has excellent cleaning performance for dirt and tartar during cleaning by the bristle tips.

However, in the case where the brush bristle material is formed of a single monofilament made of a single material up to the bristle tips, it is sometimes difficult to satisfy such a requirement. That is, when the bristle tips are formed of monofilaments made of a single material, there is a limit to the cleaning effect by the bristle tips themselves, and in particular, it may be difficult to obtain excellent cleaning performance for dirt and tartar by the bristle tips.

In brushes for cleaning and washing in other fields, the same problems are generally encountered.

Therefore, in order to improve the cleaning effect in particular, patent document 1 discloses a bristle material for a toothbrush in which a bristle material formed of a composite fiber having a core-sheath cross-sectional structure is formed into a multi-lobed cross-sectional shape having a plurality of concave portions and convex portions on the outer periphery, branched bristles formed of these convex portions are formed into a crown shape at the tip of the bristle material, and a depression is formed in the center of the crown-shaped portion. Patent document 2 discloses a brush hair material in which a tip end portion of a hair material is formed into a tapered portion, and a plurality of grooves extending in the fiber axis direction are formed in an outer peripheral surface of the tapered portion.

However, in the toothbrush bristle material disclosed in patent document 1, although the cleaning effect is enhanced by exhibiting the dirt-removing effect at the crown-shaped portion, since the depression is formed between the convex portions forming the crown-shaped portion, even if the dirt is temporarily caught in the depression at the central portion of the crown-shaped portion, the dirt is easily detached by the depression, and there is a problem that there is a possibility that the detached dirt is reattached. Further, since the convex portions forming the crown-shaped portions are formed as the intermittent convex portions protruding from the leading end of the fur material, the rib degree of each convex portion is not so high, and there is a problem that the sweeping effect may be lowered with respect to dirt having high viscosity or the like. Further, in the brush bristle material 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, even if the dirt sweeping performance (cleaning performance) is improved, the performance of capturing the temporarily swept dirt is not expected to be expected and further improvement is desired.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2012-105743

Patent document 2: japanese patent laid-open No. 2009 and 089920.

Disclosure of Invention

Problems to be solved by the invention

Accordingly, an object of the present invention is to provide a brush hair material having excellent cleaning performance, which can further improve the dirt removing performance at the hair tip portion of the hair material and can capture and prevent the temporarily removed dirt satisfactorily, and a brush using the brush hair material, focusing on the problem of leaving the hair material for a brush as described in patent document 1.

Means for solving the problems

In order to solve the above problem, a brush bristle material according to the present invention includes a composite fiber having a core-sheath cross-sectional structure including a plurality of resin layers made of 2 or more resins having different chemical dissolution rates, and formed at one end or both ends in a longitudinal direction thereof, the composite fiber including: the composite fiber comprises at least one annular wall extending in the longitudinal direction of the composite fiber and extending over the entire circumference in the direction along the outer circumferential surface of the composite fiber, and at least one groove adjacent to the annular wall on the inside of the annular wall so as to extend along the annular wall and be recessed in the longitudinal direction of the composite fiber from the leading end of the annular wall.

In the brush bristle material according to the present invention, the resin layer portion having a low chemical dissolution rate is appropriately left by the chemical dissolution treatment at one end or both ends in the longitudinal direction of the composite fiber having the core-sheath cross-sectional structure including the plurality of resin layers formed of 2 or more resins having different chemical dissolution rates to form the annular wall, and the resin layer portion having a high chemical dissolution rate is appropriately dissolved inside the annular wall to form the groove. That is, in the brush bristle material according to the present invention, since at least one annular wall extending over the entire circumference in the direction along the outer circumferential surface of the conjugate fiber is formed at the tip end portion of the conjugate fiber constituting the bristle material, the annular wall can exert a so-called fringe effect when sweeping dirt, and particularly, a high-strength structure is imparted to the annular wall itself by the annular wall structure extending continuously over the entire circumference, so that a high fringe effect can be exerted, and excellent sweeping performance can be exhibited even for dirt having high viscosity. The dirt swept away by the annular wall is caught by the groove formed in the inner side thereof and caught by the groove. The groove is surrounded by an annular wall extending over the entire circumference from the outside thereof, so that dirt caught by the groove is not easily removed beyond the annular wall portion, and is maintained in a state of being well caught in the groove. Therefore, the bristle tip portion including these annular walls and the grooves inside the annular walls exhibits excellent cleaning performance.

In the brush bristle material according to the present invention, the number of the plurality of resin layers formed of 2 or more types of resins having different chemical dissolution rates may be 2 or more, and is preferably in the range of 3 to 6. The number of the annular wall and the number of the grooves in the annular wall may be at least 1. Therefore, when the number of the plurality of resin layers is 2, the radially outermost layer in the cross section of the conjugate fiber becomes a layer forming the annular wall, and the entire inner portion thereof becomes a layer forming the groove.

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

The thickness of one resin layer in the cross section of the composite fiber is preferably in the range of 10 to 300 μm, and more preferably in the range of 15 to 150 μm. Since each resin layer is a portion where the annular wall and the groove inside thereof are formed at the end portion of the conjugate fiber, it is preferable to set the thickness of the resin layer in the above-described range in advance in order to ensure excellent dirt sweeping performance by the annular wall and excellent dirt catching performance by the groove.

In the brush bristle material according to the present invention, the diameter of the composite fibers is preferably in the range of 50 to 1,000 μm, and more preferably in the range of 80 to 500 μm. If the diameter of the conjugate fiber is less than 50 μm, the strength of the conjugate fiber portion itself becomes too weak when used in a brush, and the cleaning effect may be reduced depending on the application. If the diameter of the conjugate fiber is larger than 1,000 μm, the tenacity of the conjugate fiber portion itself becomes too strong when used in a brush, and the conjugate fiber portion at the root of the tip portion strongly presses the object side to be cleaned, although it varies depending on the form of the annular wall and the groove of the tip portion, and there is a possibility that the object to be cleaned may be easily injured.

In the brush bristle material according to the present invention, the composite fibers having the annular wall and the grooves preferably have a longitudinal length in the range of 0.5 to 10 mm. The length of the annular wall having the dirt-removing performance and the performance of the groove having the dirt-capturing performance as described above are affected, and therefore, the length may be appropriately set from the above range according to the application.

Further, in the brush bristle material according to the present invention, a structure may be adopted in which the brush bristle material has a facing wall that faces the annular wall with the groove therebetween, and the composite fibers of the facing wall have a height in the longitudinal direction that is higher than the height of the annular wall. That is, the structure is a bamboo shoot-shaped or sleeve-shaped structure in which a relatively higher wall is present on the fiber inner diameter side of the annular wall across the groove. With such a configuration, since the entire distal end portion of the bristle material can be formed into a tapered shape with a narrow distal end, it is possible to achieve soft touch and the like of the bristle distal end portion while ensuring the above-described dirt sweeping performance by the annular wall and the dirt catching performance by the groove.

In the brush bristle material according to the present invention, the at least one annular wall may have any of various shapes, and may have any of a structure formed by an annular wall extending in a circular shape and a structure formed by an annular wall extending in an irregular shape other than a circular shape. The annular wall extending in a circular shape includes not only an annular wall extending in a substantially uniform wall thickness and in a circular shape, but also an annular wall extending in a corrugated shape and an annular wall having a wall thickness varying in an extending direction. The annular wall extending in an irregular shape other than a circular shape includes an annular wall extending in a triangular shape, a quadrangular shape, or a polygonal shape of at least one of the triangular shape, the quadrangular shape, and the polygonal shape, and an arbitrary annular wall extending in an irregular shape other than a straight edge shape.

In the brush bristle material according to the present invention, the composite fibers may have a circular cross-sectional shape or an irregular cross-sectional shape other than a circular cross-sectional shape. It may be determined as appropriate depending on the application, the mode of use, the conditions of use, and the like.

In the brush bristle material according to the present invention, the plurality of resin layers constituting the conjugate fiber are preferably arranged concentrically. As long as they are concentric, they may be formed in concentric circles, in a polygonal shape other than a circular shape, or in an irregular cross-sectional shape. 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 dissolving process.

The present invention also provides a brush using at least a part of the brush hair material according to the present invention as described above. In particular, the brush according to the present invention has excellent dirt-removing performance by the annular wall formed at the tip portion of the hair material as described above and excellent dirt-catching performance by the grooves, and is therefore suitable as a toothbrush, a tongue brush, a cosmetic brush, an application brush, and the like.

The brush according to the present invention as described above differs depending on the application, but a preferable range of the brush hair length (length from the brush root to the tip of the hair) is, for example, 1 to 50mm, and more preferably 5 to 35 mm.

ADVANTAGEOUS EFFECTS OF INVENTION

As described above, according to the present invention, it is possible to provide a brush bristle material that exhibits high cleaning performance in which both excellent dirt sweeping performance and excellent dirt catching performance are achieved by the annular wall formed at the tip end of the bristle material and the groove formed inside the annular wall.

Further, according to the present invention, various brushes using at least a part of the brush hair material as described above can be provided, and a brush particularly suitable as a toothbrush, a tongue brush, a cosmetic brush, a coating brush, and the like can be provided.

Drawings

Fig. 1 shows a brush hair material according to an embodiment of the present invention, fig. 1(a) is a schematic longitudinal sectional view of one end portion of the hair material, and fig. 1(B) is a schematic cross-sectional view taken along line B-B of fig. 1 (a).

FIG. 2 is a schematic configuration diagram showing a method of implanting bristles when using a brush bristle material for a toothbrush.

Fig. 3 is a schematic longitudinal sectional view of one end portion of a brush bristle material according to another embodiment of the present invention.

Fig. 4 is a schematic cross-sectional view showing various embodiments of the brush bristle material according to the present invention.

FIG. 5 is a schematic cross-sectional view showing another example of various forms of the brush hair material according to the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 shows a brush bristle material 1 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. 1B, the brush hair material 1 is formed of a composite fiber 3 having a core-sheath cross-sectional structure including a plurality of

resin layers

2a, 2B, 2c, 2d formed of 2 or more resins (2 resins in the example of the figure) having different chemical dissolution rates, and particularly, in the present embodiment, includes a plurality of

resin layers

2a, 2B, 2c, 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 batt material 1), there are formed: at least one annular wall 4 extending in the longitudinal direction of the composite fiber 3 and extending over the entire circumference in a direction along the outer circumferential surface of the composite fiber 3, and at least one groove 5 adjacent to the annular wall 4 on the inside of the annular wall 4, extending along the annular wall 4 and recessed in the longitudinal direction of the composite fiber 3 from the tip of the annular wall 4. In the present embodiment, the annular wall 4 is formed as a circular annular wall extending with the same thickness in the extending direction thereof, and the groove 5 is formed as an annular groove extending with the same width along the annular wall 4 inside the annular wall 4. The annular wall 4 is formed of the resin layer 2c that does not dissolve but remains properly in the chemical dissolution process, and the inner groove 5 is formed as an annular space formed by properly dissolving the resin layer 2b in the chemical dissolution process. In the present embodiment, the resin layer 2a forms the cylindrical wall 6 which is not dissolved in the chemical dissolving process but remains appropriately at one end of the batt material 1, and the resin layer 2d forms the annular space 7 by being appropriately dissolved in the chemical dissolving process.

As the chemical dissolving treatment, for example, an alkali treatment may be applied, and as the plurality of resin layers formed of 2 or more resins different in chemical dissolving rate (for example, dissolving rate by the alkali treatment), for example, the resin layers 2a and 2c are formed of nylon (Ny) (registered trademark) which is a resin insoluble in alkali, and the resin layers 2b and 2d are formed of polybutylene terephthalate (PBT) which is a polyester resin soluble in alkali, and only the resin layers 2b and 2d at the end portions are dissolved by alkali treatment of only a predetermined length of the longitudinal end portions of the composite fiber 3, thereby forming the end portions of the brush bristle material 1 having the annular wall 4, the cylindrical groove 5, the wall 6, and the annular space 7 as shown in fig. 1 (a).

In this brush hair material 1, a resin layer 2c having a slow chemical dissolution rate (formed of a resin layer insoluble in alkali in the above embodiment) is partially left by chemical dissolution treatment at one end or both ends in the longitudinal direction of a composite fiber 3 having a core-sheath cross-sectional structure including a plurality of resin layers formed of 2 or more resins having different chemical dissolution rates to form a ring-shaped wall 4, and a resin layer 2b having a fast chemical dissolution rate is appropriately dissolved inside the ring-shaped wall to form a groove 5. Since the annular wall 4 is formed as an annular wall extending continuously in an annular shape over the entire circumference, the annular wall 4 can exhibit a high edge effect when sweeping dirt, and can exhibit excellent sweeping performance even for dirt having high viscosity. The dirt swept away by the annular wall 4 is caught by the groove 5 formed on the inner side thereof and captured by the groove 5, but since the groove 5 is surrounded by the annular wall 4 extending over the entire circumference from the outer side thereof, the dirt captured in the groove 5 is not easily detached, and is maintained in a state of being well captured in the groove 5. Therefore, the bristle tip portion including the annular wall 4 and the groove 5 inside thereof exhibits excellent cleaning performance.

The brush bristle material 1 configured as described above is used at least partially for the production of various brushes. In general, as a method for implanting bristles into a brush constituting member, two typical methods are known, and the two methods will be described with reference to fig. 2, taking a case of using the brush constituting member in a toothbrush as an example.

Fig. 2(a) shows a toothbrush 13 in which bristles are implanted into a head portion of a toothbrush component 12, and as a method of implanting the bristles 11, there are two methods as shown in fig. 2(B) and (C) which are enlarged cross-sectional views taken along line a-a of fig. 2 (a). In the method shown in fig. 2(B), the brush bristle material 11 folded in two is inserted into the bristle-implanting hole 14, and the brush bristle material 11 is fixed to the toothbrush constituent member 12 by a fixing tool called an anchor 15. The finished toothbrush is commonly referred to as an anchor toothbrush. In such anchor sheet toothbrush, both end portions of the brush bristle material 11 prepared in advance become bristle tips of the brush. In the method shown in fig. 2C, one end portion of the brush bristle 11 is inserted into the through-hole 16 of the head front side member 12a of the toothbrush component member 12, a heating device (not shown) is applied to the inserted end portion of the brush bristle 11 to form a block called a hot ball 17 for detachment or fixation, and thereafter, the head rear side member 12b is joined to hide the hot ball 17, thereby completing a commercial toothbrush product. The finished toothbrush is commonly referred to as an anchorless toothbrush. In such an anchor-free toothbrush, one end of the brush bristle material 11 prepared in advance serves as a bristle tip of the brush. Therefore, in the brush hair material 1 according to the present invention, the annular wall 4 and the groove 5 formed inside thereof are formed at both end portions of the brush hair material 1 when used in an anchor toothbrush, and the annular wall 4 and the groove 5 are formed at one end portion of the brush hair material 1 when used in a non-anchor toothbrush.

Fig. 3 shows one end 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 formed of a composite fiber 23 having a core-sheath cross-sectional structure including a plurality of

resin layers

22a, 22b, 22c, and 22d arranged concentrically and formed of 2 or more types of resins (2 types of resins in the example of the figure) having different chemical dissolution rates. At one end or both ends in the longitudinal direction of the composite fiber 23 (fig. 3 shows only one end of the batt material 21), there are formed: at least one annular wall 24 extending in the longitudinal direction of the composite fiber 23 and extending over the entire circumference in a direction along the outer circumferential surface of the composite fiber 23, and at least one annular groove 25 adjacent to the annular wall 24 on the inside of the annular wall 24, extending along the annular wall 24 and recessed in the longitudinal direction of the composite fiber 23 from the tip of the annular wall 24. 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 an alkali as a dissolving chemical (e.g., polybutylene terephthalate (PBT)), the resin layers 22b and 22d are made of, for example, a resin having a faster dissolution rate with respect to an alkali as a dissolving chemical (e.g., polyethylene terephthalate (PET)), the annular wall 24 is formed by the resin layer 22c that is not dissolved and remains appropriately in the chemical dissolving process, the groove 25 is formed by appropriately dissolving the resin layer 22b in the chemical dissolving process, the columnar wall 26 that is a central portion of the opposing wall higher than the annular wall 24 is formed by the resin layer 22a that is not dissolved and remains appropriately in the chemical dissolving process, and the annular space 27 is formed by appropriately dissolving the resin layer 22d in the chemical dissolving process. Further, the cylindrical wall 26 at the center portion and the annular wall 24 having a height lower than that of the cylindrical wall form a bamboo shoot-like or sleeve-like structure, and the entire distal end portion of the fur material 21 is formed in a tapered shape with a narrow distal end.

In the brush hair material 21 having the tapered shape with the narrow tip end, as in embodiment 1, excellent dirt cleaning performance by the annular wall 24 and excellent dirt catching performance by the groove 25 can be exhibited to exhibit excellent cleaning performance, and by forming the tapered shape with the narrow tip end, as compared with embodiment 1, excellent cleaning effect can be exhibited even for a finer part (for example, interdentium).

Representative characteristics in the case of applying to a toothbrush are summarized in table 1 for the above-described embodiment 1 and embodiment 2. In embodiment 1, the annular wall is formed of a resin layer containing nylon (Ny) (registered trademark), and the groove is formed of a resin layer containing polybutylene terephthalate (PBT), and in embodiment 2, the annular wall is formed of a resin layer containing polybutylene terephthalate (PBT), and the groove is formed of a resin layer containing polyethylene terephthalate (PET), and each is formed by alkali treatment. The characteristics of the brush bristles in table 1 are shown as comparative characteristics with those of a brush bristle formed of a monofilament of nylon (registered trademark) which is a generally conventional single material, and the dirt sweeping effect and the dirt catching effect of the brush bristle based on the bristle tip portion are shown as comparative characteristics with those of the bristle described in patent document 1. O in table 1 indicates that the composition has equal or higher properties than the comparative object, and x indicates that the composition is significantly superior to the comparative object.

[ Table 1]

。

The brush bristle material according to the present invention can take various forms in addition to the above embodiments 1 and 2. In fig. 4 and 5, the cross-section of the composite fiber shows various forms.

In the brush bristle material 31 shown in fig. 4(a), the resin layer 32b is formed as an annular wall 34, and the resin layer 32a in the central portion is formed as a groove 35 inside the annular wall 34, while the composite fiber 33 including the resin layer 32a, the resin layer 32b outside the central portion, and the outermost resin layer 32c is formed concentrically. In the brush bristle material 41 shown in fig. 4(B), a composite fiber 43 including a resin layer 42a, an outer resin layer 42B, an outer resin layer 42c, and an outermost resin layer 42d concentrically arranged in a central portion is formed, and the resin layers 32B and 42d are formed as annular walls 44, respectively, and the resin layers 42a and 42c are formed as grooves 45 inside the respective annular walls 44. In the brush hair material 51 shown in fig. 4(C), a composite fiber 53 is formed including a resin layer 52a, a resin layer 52b, a resin layer 52C, a resin layer 52d, a resin layer 52e, and a resin layer 52f as outermost layers, which are concentrically arranged in a central portion, the resin layers 52C and 52e are formed as annular walls 54, the resin layers 52b and 52d are formed as grooves 55 inside the annular walls 54, and the resin layer 52a in the central portion is formed as a cylindrical wall 56 in the central portion. In the brush bristle material 61 shown in fig. 4(D), a composite fiber 63 including a resin layer 62a, a resin layer 62b, and an outermost resin layer 62c is formed concentrically, the outermost resin layer 62c is formed as an annular wall 64, the resin layer 62b is formed as a groove 65 inside the annular wall 64, and the resin layer 62a is formed as a cylindrical wall 66 in the center.

Further, in the brush bristle 71 shown in fig. 5(a), the resin layer 72b is formed as a triangular resin layer, the resin layer 72b is formed as an annular wall 74, and the resin layer 72a in the central portion is formed as a groove 75 inside the annular wall 74, although the composite fiber 73 including the resin layer 72a in the central portion, the resin layer 72b outside, and the outermost resin layer 72c are arranged concentrically. In the brush bristle material 81 shown in fig. 5(B), the composite fiber 83 is formed to include a resin layer 82a at the center, a resin layer 82B on the outer side, a resin layer 82c on the outer side, a resin layer 82d on the outer side, and a resin layer 82e on the outermost layer, which are concentrically arranged, but the resin layers 82B and 82d are formed as resin layers extending in a corrugated shape in a ring shape, the resin layers 82B and 82d form ring-shaped walls 84, respectively, and the resin layers 82a and 82c on the inner side form grooves 85 inside the ring-shaped walls 84, respectively. In the brush bristle material 91 shown in fig. 5(C), the composite fiber 93 including the resin layer 92a, the resin layer 92b, the resin layer 92C, the resin layer 92d, and the outermost resin layer 92e, which are concentrically arranged, is formed, but the resin layers 92b and 92d are formed in a petal-like shape in which the resin layer thickness varies in the annular extending direction, the resin layers 92b and 92d are formed as annular walls 94, and the resin layers 92a and 92C, which are inside, are formed as grooves 95 inside the respective annular walls 94. In the brush bristle material 101 shown in fig. 5(D), the composite fiber 103 is formed to include a resin layer 102a, a resin layer 102b on the outer side thereof, and an outermost resin layer 102c, which are concentrically arranged, and the composite fiber 103 and the

resin layers

102a, 102b, and 102c are formed in a hexagonal shape in cross section, the outermost resin layer 102c is formed as an annular wall 104, the resin layer 102b is formed as a groove 105 inside the annular wall 104, and the central resin layer 102a is formed as a cylindrical wall 106 in the center.

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

Examples

Hereinafter, examples of the present invention will be described.

Examples 1 to 11 and comparative example 1

[ production of Brush wool Material ]

As the raw material, polybutylene terephthalate ("TORAYCON" (registered trademark) 1100SW "manufactured by Toray Industry inc.), polyethylene terephthalate (" PET ", manufactured by Toray Industry inc., T755M), nylon 610 (" AMILAN "(registered trademark) CM 2001", manufactured by Toray Industry inc., Ny11-PTMG (polytetramethylene glycol), "PEBAX" (registered trademark) 72R53, manufactured by Arkema, and polybutylene naphthalate (PBN, manufactured by toyobo co., AE-500) were dried and prepared under recommended conditions. As shown in table 2, the core component, the resin type of the sheath component, the area ratio of the core component to the sheath component, the number of resin layers, and the thickness (representative value) of the resin layers were melt-spun into a conjugate fiber having a core-sheath cross-sectional structure including a plurality of resin layers. The core component referred to herein is a component of the resin layer disposed at the center in the cross section of the fiber, and the sheath component is a component of the resin layer disposed except for the center in the cross section of the fiber. The resin layer of the fiber cross section has a structure in which the core component, the sheath component 1, (the sheath component 2), the core component, and … … are repeated in this order from the center.

The melt-blown fiber was cooled and solidified in water, and then stretched 4.5 times in a dry atmosphere at 120 ℃ in a warm water at 60 ℃ as a first stage, and then subjected to relaxation heat setting in a dry heat atmosphere to obtain a core-sheath composite fiber. The composition of the obtained core-sheath composite fiber is shown in table 2.

The fibers were bundled into a straight line having a bundle diameter of 45mm, and then packaged, followed by cutting into a predetermined length. Then, the bundle of composite fibers is immersed in a caustic soda solution heated to expose the cut end faces, and both end portions are dissolved and removed to form an annular wall. The length of the portion having the annular wall and the groove in the longitudinal direction was controlled by changing the immersion time in the caustic soda solution. The characteristics of the obtained brush hair material are shown in Table 2.

As comparative example 1, a brush hair material was produced in which PBT fibers were immersed in a caustic soda solution in the same manner as described above and both end portions were tapered so as to be thin at the tips.

[ production of toothbrush ]

The brush hair material obtained by the method is arranged on an anchor sheet type hair planting machine, a specified number (about 15-40) is selected, and the brush hair material and the anchor sheet are folded in half and punched into hair planting holes of a toothbrush head. As the toothbrush head, a toothbrush head having implanted holes of 1.5mm in diameter and 8 rows and 4 columns of implanted parts was used. The lengths (mm) and the numbers (root/hole) of the bristles of the toothbrushes manufactured in examples and comparative examples are shown in Table 2.

The following evaluations were made for each of the obtained toothbrushes, and the results shown in table 2 were obtained.

[ evaluation of cleanability ]

Artificial tartar manufactured by ニッシン was applied to the tooth arrangement model and dried for 5 minutes or more. The toothbrush containing water was pressed from the upper surface of the tooth arrangement model with a load of 230g, and brushing was performed under conditions of a stroke width of 70mm and a stroke speed of 180 mm/sec in the direction along the tooth arrangement. For evaluation of the tooth surface, the upper side of the molar part of the tooth arrangement model was used, and for evaluation between teeth, the outer side of the incisor part was used. The cleaning performance was calculated from the number of brushing times until the standard, based on the remaining amount of dirt when a nylon bristle toothbrush was brushed for 20 times, by the following equation.

Cleanability =20 ÷ (number of brushing times up to baseline).

[ evaluation of durability of Hair opening ]

A brush was subjected to sliding motion 1000 times in the longitudinal direction of the brush under the conditions of a stroke width of 70mm and a stroke speed of 180 mm/sec with respect to a corrugated plate made of stainless steel in a state in which water at 37 ℃ was dropped while a load of 230g was applied perpendicularly from the inner side of the sliding surface, and the opening ratio of bristles of the brush part was measured. In the method of calculating the hair spreading ratio, the lateral width of the brush portion in the initial state is represented as Amm, and the lateral width after the sliding is represented as Bmm, (B-A)/A × 100%.

[ evaluation of durability to Hair cracking ]

Under the same conditions as the evaluation of the hair opening durability, the number of times of brushing was observed for the split of the hair tip every 50 times, and the number of times of the hair material in which the hair split occurred reached 5 was recorded.

[ tactility seed blistering evaluation ]

20 adults were allowed to use the toothbrush for 30 days, and responses were requested according to the following criteria, and the average score was counted as an evaluation value.

Fractional tactile blistering

5 very Soft foaming very good

4 good softness and foaming

3 common good without bad

2 hard blister difference

1 very hard lather very poor.

[ Table 2]

。

Industrial applicability

The present invention can be applied to any brush, and is particularly suitable for a toothbrush, a tongue brush, a cosmetic brush, a coating brush, and the like.

Description of the reference numerals

1. 21 Brush wool 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 wool

12 toothbrush constituent

12a head front side member

12b head back side member

13 toothbrush

14 hair planting hole

15 anchor sheet

16 through hole

17 heat ball

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, 103 composite fiber

34. 44, 54, 64, 74, 84, 94, 104 annular wall

35. 45, 55, 65, 75, 85, 95, 105 grooves

56. 66, 106 cylindrical walls.

Claims

1. A brush hair material characterized by having a core-sheath cross-sectional structure, wherein at one or both ends in the longitudinal direction of a composite fiber having a plurality of resin layers comprising 2 or more resins having different chemical dissolution rates, there are formed: at least one annular wall extending in the longitudinal direction of the composite fiber and extending over the entire circumference in a direction along the outer circumferential surface of the composite fiber, and at least one groove adjacent to the annular wall on the inside of the annular wall so as to extend along the annular wall and recessed in the longitudinal direction of the composite fiber from the leading end of the annular wall,

the number of the plurality of resin layers is in the range of 4-6 layers.

2. The brush bristle material according to claim 1, wherein one resin layer in the cross section of the composite fiber has a thickness in the range of 10 to 300 μm.

3. The brush bristle material according to claim 1, wherein the composite fibers having the annular wall and the groove have a length in the lengthwise direction in the range of 0.5 to 10 mm.

4. The brush bristle material according to claim 1, wherein a counter wall is provided that faces the annular wall across the groove, and the composite fibers of the counter wall have a greater height in the longitudinal direction than the height of the annular wall.

5. The bristle material for brushes of claim 1, wherein the at least one annular wall is formed by an annular wall extending in a circle.

6. The bristle material for brushes of claim 1, wherein the at least one annular wall is formed by an annular wall extending in an irregular shape other than a circle.

7. The brush bristle material according to claim 1, wherein the plurality of resin layers are provided concentrically.

8. A brush using at least a part of the brush hair material according to any one of claims 1 to 7.