SK3282003A3 - Method for producing bristle products - Google Patents

Abstract

The invention relates to a method for producing bristle products. Individual bristles or groups of bristles consisting of synthetic material are fixed to a carrier in a predetermined arrangement, forming the desired bristle area. At least one part of the bristles in the predetermined arrangement or in the fixed bristle area is structured by means of laser beams in a contactless and preferably regular manner. Furthermore, the bristles are shortened in a contactless manner at the free ends thereof by means of laser beams. In this way, structures are produced in a reproducible form on the outer and upper side of the bristle area, said structures assisting the cleaning action.

Description

Method of making goods with bristles

Technical field

The invention relates to a method for producing bristle articles by attaching individual or grouped bristles to a carrier in a predetermined configuration to form the desired bristle stock, wherein at least a portion of the bristle stock bristles are structured on their sheath.

The invention further relates to a method for manufacturing bristle articles by attaching individual or grouped bristles to a support in a particular configuration to produce the desired bristle stock, wherein the free ends of at least a portion of the bristles are shortened by machining.

BACKGROUND OF THE INVENTION

Usually, the bristle goods consist of a more or less regular bristle fitting in which the bristles used have a smooth surface on their sheath, while the free bristle ends lie in a flat or continuous or discontinuously curved packaging surface. The ends of the bristles primarily have the task of producing a cleaning, abrasive or polishing effect by mechanical action on the surface, while the bristle sheath primarily performs a wiping action. The necessity of arranging a large amount of bristles within the bristle stock essentially results from the requirement for effective and above all surface cleaning. On the other hand, the bristle sheath, according to the method of determination, is essentially only effective in the brushing process as far as the bristles lying in the bristles are externally, while the inside bristles essentially only care for the supporting effect of the bristles between themselves and perform an additional task of keeping the coating media or media that are important for the brushing effect in the thin capillaries between the bristles.

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Attempts have also been made to attribute a cleaning, polishing or abrasive effect to both the brushing process and the bristle sheath by structuring, for example, bristles of the bristles fitted with bristles after the bristles are finished, see US 5,678,275. However, this type of machining does not lead to satisfactory results, in particular, no perfectly localized and geometrically predetermined structures can be produced, because the bristles deflect due to their flexibility and moreover have different flexibility depending on the position within the bristle setting and the distance from the mounting point.

Another applicant's proposal, see WO 99/661111, is to structure monofilaments produced by extrusion by laser processing on a monofilament sheath for the production of bristles. The monofilaments are then twisted into strands. The bristles are shortened to the required size. Since the monofilaments are axially displaced relative to each other when twisted on the strands, no locally defined structure can be formed on the bristles assembled to the bristles. In addition, due to the structure, too thick bristles can be handled in the usual separation into groups, for example bundles. This results in the number of bristles varying strongly in one bundle. In this method, it is also not possible to arrange structured bristles only in the outside of the bristle setting area where they exert the greatest effect. On the other hand, the bristles lying inside are less effective or even ineffective in their structure. Thus, when processing a monofilament, unnecessarily much material is structured and possibly also weakened. In addition, the manufacturing process in the production of monofilaments is slowed by the laser treatment.

It has almost been found that the flat surface of the bristles, or the wrapping surface of the free ends of the bristles, in many cases allows the use, in particular for toothbrushes, of inadequate cleaning only. In toothbrushes, the bristles of such a bristle fit follow very differently the curvature of the teeth and the interdental spaces remain far untreated. Therefore, very different topographies have been proposed for brushing with toothbrushes. Also, these topographies are generally formed by additional mechanical removal of the plastic at the ends of the bristles, i.e. by cutting the bristles, see, for example, U.S. Pat.

2,227,126, DE 198 32 436 and EP 0 736 270. This is an abrasive or cutting operation with relatively expensive mechanics. Also, the possibility of variations is very limited. Better results are obtained by shifting the bristles axially relative to each other prior to their attachment to the support, see EP 0 346 646, so that any topographies can theoretically be formed. This method provides for an additional processing step before the bristles are attached to the support. Also, the bristles with a given topography must then be held in position and coupled to the bristle carrier in that position.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a method for producing bristle articles by means of which the bristle sheath can be structured in any but reproducible manner before or after attachment to the bristle carrier. Further, the bristle ends may be shortened to form any but reproducible bristle end surfaces.

SUMMARY OF THE INVENTION

The first part of the object of the invention is solved in that at least a portion of the bristles are contactlessly structured by laser beams on a predetermined arrangement or on a fixed bristle shoulder.

Although it is known, see DE 198 29 943 to affix marking on the finished bristle fitting by means of laser beams to serve as a wear indicator. Thereby, however, there is no structuring, since the bristle material itself does not deteriorate.

Today's laser technology provides the ability to locate the effects of the laser beam very precisely and concentrate its action on the smallest areas up to individual points or lines. Furthermore, it provides the possibility of adapting the material to be worked and allows for an exact adjustment of the depth effect depending on the material. By using the laser energy according to the invention, therefore, defined and regular structures can be formed on the bristle surface of the bristle-set in a preferably geometric arrangement. The mechanical effect of the structures can also be influenced by controlling the depth of action of the laser beams. Since the method works in a contactless manner, reproducible structures can be formed independently of the bristle flexibility. This is particularly true of plastic bristles, although the invention is not limited to this material. Laser technology further provides the ability to customize structures according to the type and arrangement of purpose. The structures also improve the absorption properties for cleaning and coating media, which can be perfectly transferred and also washed away without difficulty due to the smooth surface of the structures.

The structures further increase the massage effect for toothbrushes and body brushes and, for technical brushes with abrasive substances in bristles, the abrasive effect on the edges of the structures.

The method according to the invention can also be used for producing bristle-topping topographies by shortening the bristles at their free ends by means of laser beams.

In this way according to the invention, the finest structures, for example point or line depressions, can be formed into the surface of the bristle arrangement or the bristle setting, with the result that the coating surface has stages of every kind which develop an additional wiper and scraper effect.

In one preferred embodiment, the laser source is controlled such that the bristles are rounded at their free ends during the laser treatment by thermal stress. While structuring takes place essentially by evaporation or gasification of the plastic under the influence of the laser energy introduced, it has surprisingly been found that, when the bristles of the free bristle ends are shortened, the bristle end is, as always required, dome-rounded. The reason could be that the molecules, due to the production of monofilaments in bristles, are linearly oriented, in place, processed by laser beams, are thermally stressed, and thus these molecules are transformed into their knuckle shape.

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Further, the laser source is constructed, depending on the respective material, in particular plastic, such that the bristles on their sheath are profiled by the removal of the material due to the thermal decomposition of the plastic. This also involves evaporation and gasification processes that lead to material removal. It has j

over all mechanical processing, the advantage is that no fragmented structures will arise which, in the use of bristled goods, lead to tearing of the material, which in turn can lead to intolerance in the case of hygienic brushes, in particular toothbrushes; layer. During mechanical processing, the remaining material remains on the bristles, which in turn require a cleaning and purification process without guaranteeing 100% success. Also, such purification may be omitted in the process of the invention.

According to another embodiment of the method according to the invention, the bristles on their sheath can be structured by foaming the plastic. Indeed, practical tests have shown that, as a result of the laser treatment, bubbles are formed in the plastic material which appear as roughness on the surface of the sheath. This foaming can be controlled by fillers, laser guidance and the like.

Two-component or multi-component bristles are known which consist of a core and a sheath. In particular, they are used to indicate wear, since the core and sheath are differently colored and, first of all, monochromatic bristles allow, with increasing wear, to recognize at the end of the bristle a different color effect that is representative of a certain degree of wear. In the case of bristles with such bristles, according to an embodiment of the invention, it is envisaged that only the package is structured by laser beams. In this case, the package can be structured to the core by local removal of the package material.

In order to avoid adversely affecting the properties predetermined by the bristle cross-section and the plastic selected by the additional structuring, it is provided according to the invention that the bristles on their skin are only structured to a depth of up to 10% of the bristle cross-section. Moreover, the depth and local arrangement of the structures within the bristle stock may be selected such that the static properties of the individual bristle and the entire bristle stock remain within the desired range.

When creating topographies, the free ends of the bristles may be shortened in a substantially linear pattern. This line pattern may be adapted to the directions of movement that are common to the bristle-like article in order for the topography to operate in an optimal manner.

It is further proposed that the free ends of the adjacent bristles be shortened to form a stepped covering surface.

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Further, it is possible to shorten the free ends of only individual bristle groups by laser beams, and it is also possible to shorten the free bristle ends of an individual bristle group to form a sheath that differs from the planar, for example to taper the bundle at its end.

As already explained, the method according to the invention can be carried out on a prepared bristle arrangement or on a fixed bristle fit. Only bristles lying on the outside can be structured on their shell. Instead or in addition to this, it is possible to release the bristles lying inside the bristles by separating and laterally deflecting the bristles, see for example DE 198 32 436 and EP 0 736 270, and to structure them on their sheath.

Although most of the plastics in question for the bristles may be structured to a greater or lesser extent by laser irradiation, it may be advisable to use bristles with laser beam absorbing fillers, whereby structuring can be controlled more easily and more targeted. Fillers may also be used only in certain areas of the bristle cross-section, for example in the vicinity of the sheath, or, in the case of profiled cross-section bristles, in the outer regions of the profile. In this way, particularly in the case of polygonal cross-sectional shapes in connection with the structuring according to the invention, particularly intense mechanical effects are produced in the region of the polygon edges at the brushing.

Finally, the structuring by laser treatment can be visualized by the simultaneous coloring of the plastic. Instead, or in addition to this, the laser-treated structure can be visualized in the bristle plastic by fillers reacting to the laser rays by coloring.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described and explained in more detail with reference to the accompanying drawings, in which: FIG. 1 to FIG. 6 shows a side view of the toothbrush head, with different structures on the bristle sheath, FIG. 7 and FIG. 8 shows a side view of a toothbrush head with structures on the bristle shell and topography at the bristle ends; FIG. 9 to FIG. 11 is a plan view of a toothbrush head with various line topographies; FIG. 12 to FIG. 14 is a perspective view of a toothbrush head with various structures or topographies; FIG. 15 to FIG. 17 is a plan view of the bristles of the replacement toothbrush head for different toothbrushes, with various topographies; FIG. 18 shows another embodiment corresponding to FIG. 13 and FIG. 14, FIG. 19 to FIG. 21 shows a modified embodiment according to FIG. 1 to FIG. 8, FIG. 22 to FIG. 24 shows the structured individual bristles, and FIG. 25 round brush in perspective view.

DETAILED DESCRIPTION OF THE INVENTION

The toothbrush 1, shown in the sectional drawings, has a head which forms a bristle carrier 2, which in the embodiment according to FIG. 1 to FIG. 12 mounted on the carrier 2 solely in a single arrangement, so that the bristle fit 4 consists of a relatively dense bristle arrangement with thin capillaries therebetween. In the exemplary embodiment according to FIG. 1 formed by removing material on the bristle sheath of the structure 5 in the form of parallel lines. The structuring of FIG. 1 provides particularly favorable effects for a cleaning method known as the "red-white cleaning method".

In the embodiment of FIG. 2, in which also the bristle fitting 4 of the individually arranged bristles 3 is shown, by means of laser beams, the wavy line-shaped structures 5, which have, compared to FIG. 1 smaller width.

In the embodiment of FIG. 3, the structures 5 are formed on the outside bristles of the shoulder 4 with a bristle-like bracing, and in the embodiment of FIG. 4 in a cross-hatch method. The embodiments of FIG. 2 to FIG. 4 are suitable for any tooth cleaning method.

The embodiment of FIG. 5 shows the structures 5 of the outside bristles in the form of circular surface depressions, while FIG. 6 shows the structures 5 in the form of circles.

In the embodiment of FIG. 7, the bristles 3 of the bristle shoulder 4 are of different lengths, i.e. in the region of the front end of the brush head 2, they are longer than in the other bristle shoulder area, so that a topography with a step in the front region is formed. Only in this front region are structures 5 formed into the skin of the bristles lying on the outside, similar to FIG. First

In the embodiment of FIG. 8, the bristle shoulder 4 has a topography in which the ends of part of the bristles 3 lie in one plane and the ends of the remaining part of the bristles forming group 6 in a plane which is higher than the bristle carrier 2. In this exemplary embodiment, only the projecting bristles of Group 6 are provided with linear structures.

In FIG. 9 to FIG. 11 shows a toothbrush head 2 with a bristle shoulder 4 in a plan view of the free ends of the bristles 3. The outer contour of the bristle brace 4 follows approximately the contour of the toothbrush head 2. In the embodiment of FIG. 9, the bristles are shortened by laser beams only in the region of the front end of the brush head, namely on the concentric lines 7 of the polygon. In the embodiment of FIG. 10, the bristles 3 are shortened in a regular cross-hatch pattern 8, while in the embodiment of FIG. 11 are truncated along line 9.

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Fig. 12 shows a perspective view of a toothbrush head 2 in which the outside bristles on their housing again have a structure 5 of parallel lines, while at the same time the bristles in the region of the front end of the head are shortened in the form of cross-hatching.

In the embodiment of FIG. 13, the bristles with 4 bristles consist of groups of 9 bristles which are formed as round tufts. In the front region, the brush head 2 has groups 10 and 11 in which the free ends of the bristles have been shortened differently by means of laser beams, so that the groups 10 and 11 at their free ends extend differently conically. Furthermore, the bristles lying on the conical surface can also be structured on their sheath.

In the embodiment of FIG. 14, the bristle recess 1 comprises in turn cylindrical bundle groups 9, while a group 12 of individually arranged bristles is formed in the front region of the brush head. In this embodiment, only the bristles 3 of this group 12 are provided with linear structures 5 which run parallel to each other.

In FIG. 15 to FIG. 17 is a plan view of a 4-bristle rounded head brushing 4, as is particularly used for electric toothbrushes. According to FIG. 15, the bristles 3 are shortened along the concentric rings 13, while in the embodiment of FIG. 16, the bristles 3 are shortened in such a way that a spiral topography is produced. Finally, in the embodiment of FIG. 17 bristles truncated along line 15 passing through the common point. The embodiments of FIG. 16 and FIG. 17 in particular support the action of the free ends of the bristles when the toothbrush head is rotated about its central axis.

Fig. 18 shows a toothbrush head 2 similar to the toothbrush head 2 of FIG. 13 and FIG. 14, wherein the bristles 4 are formed from groups 9 of bristles which are formed as round tufts and groups 12 of bristles arranged at the front end. The front group 12 of bristles consists of individual bristle strips that are star-shaped, the individual bristles having parallel structures 5 which are substantially perpendicular to the bristle axis.

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In the embodiments of FIG. 19 to FIG. 21, the individual structures 5, which have been formed by laser beams on the outside bristles of the bristle stock 4, are arranged irregularly but in a statistical distribution over the entire side surface of the bristle stock regularly.

For individually arranged bristles, especially if they have a larger diameter, their sheath may be structured in the same manner as described above for the entire bristle stock or for the bristle groups of one such bristle. In the embodiment of FIG. 22, the bristle sheath 3 is provided with obliquely extending structures 5, while in the embodiment of FIG. 23 shows a zigzag line structure 5. Also, the bristle 3, as shown in FIG. 24, cross-hatched structure.

Fig. 25 shows a round brush with a cylindrical carrier 1. This may be, for example, a hairbrush head, a technical brush or a similar type of brush. Cylindrical bristle groups 16 are attached to the carrier 1 and are provided with parallel running structures 5 from their free ends.

Claims (18)

PATENT CLAIMS Method for producing bristle goods (1), in which individual or grouped bristles (3) are mounted on a support (2) in a predetermined arrangement to form the desired bristle stocking, wherein at least a portion of the bristle stocking is treated By means of laser beams, characterized in that at a predetermined arrangement or on a fixed bristle (4), at least a portion of the bristles (3) on its housing are contactlessly structured by laser beams. Method according to claim 1, characterized in that the bristles are structured regularly. I Method according to claim 1 or 2, characterized in that the free ends of at least a portion of the bristles are shortened by removing the material without contact on the free ends of the bristles (3) of a predetermined arrangement or fixed bristle setting by means of laser beams. Method according to claim 3, characterized in that the shortened bristles (3) are rounded at their free ends during the laser treatment by thermal stress. Method according to one of Claims 1 to 4, characterized in that the bristles (3) are shaped or shortened at their ends by removal of material on account of the thermal decomposition of the plastics material. c c r r. C r r f r f, ·, ·. e. r r t. r r t r · C <'<' r Method according to one of Claims 1 to 5, characterized in that the bristles (3) are structured on their skin by foaming the plastic. Method according to one of Claims 1 to 6, characterized in that, in the case of two-component bristles, which consist of at least a core and a concentrically surrounding envelope, only the envelope is structured by laser beams. Method according to claim 7, characterized in that the sheath except the core is structured by local removal of the sheath material. Method according to any one of claims 1 to 8, characterized in that the bristles on their skin are structured to a depth of approximately 10% of the bristle cross-section. Method according to any one of claims 1 to 9, characterized in that the free ends of the bristles (3) lying substantially on the surface lines (7, 8, 9, 13, 14, 15) of the predetermined arrangement or fixed shoulder are shortened. bristles. Method according to one of claims 1 to 10, characterized in that the free ends of the adjacent bristles (3) are shortened to form a stepped bristle end surface (6). Method according to one of claims 1 to 11, characterized in that the free ends of the individual bristle groups (6) are shortened. r r C C c p CC r C C Method according to one of Claims 1 to 12, characterized in that the free bristle ends (3) of the individual bristle group (10, 11) are shortened to form a coating surface different from the plane. Method according to one of Claims 1 to 13, characterized in that the sleds of a predetermined arrangement or a fixed bristle fit only structure the bristles lying on their outer surface. Method according to one of Claims 1 to 14, characterized in that, on a predetermined arrangement or on a fixed bristle step, the bristles are detached inside the bristles by separating or laterally deflecting the bristles, and the bristles are structured on their sheath. Method according to one of Claims 1 to 15, characterized in that bristles (3) with laser beam-absorbing fillers are used for the manufacture of bristle articles. Method according to one of Claims 1 to 16, characterized in that the structure (5) formed during the laser treatment is visualized by coloring the plastic. . Method according to any one of claims 1 to 16, characterized in that the structure (5) formed during the laser treatment is visualized by fillers in the plastic mass of the bristles (3) reacting to the laser rays by changing the color.