ES2219925T3 - PIGS OR INTERDENTAL CLEANER OF A MONOFILAMENT. - Google Patents

Abstract

Bristles (6) or interdental cleaners made of a monofilament (1) with reduced secondary bonding forces of at least two polymers jointly extruded in a geometrically regular arrangement, with limiting surfaces running essentially axially, where the bristles (6) or interdental cleaners are essentially cleft axially by the action of mechanical forces, characterized in that the monofilament has a matrix (2) of a first polymer that determines the physical and chemical characteristics of the bristles (6) or interdental cleaners, and because the second polymer is included in the matrix in the form of thin limiting layers (3), the reduced secondary bonding forces prevailing in the limiting layers (3) and the bristles (6) or the interdental cleaners being able to split in the limiting layers.

Description

Sows or interdental cleaner of a monofilament

The invention relates to bristles or cleaners interdentals made of a monofilament with binding forces reduced secondary of at least two polymers together extruded in a geometrically regular arrangement, with limiting surfaces that run essentially axial, for the manufacture of bristles or interdental cleaners that they are essentially cleft axially by the action of mechanical forces The invention is also directed to a procedure for the manufacture of bristles or cleaners interdigitals made of monofilaments of this type, and to products of bristles with bristles of this type or cleaners interdigital

Bristles for bristle products of any type, for example, brushes for the body and for oral hygiene, Household cleaning brushes, technical brushes, brushes and similar, they are manufactured today mainly from polymers extruding the polymer melt to give monofilaments without end, the monofilaments are stretched and eventually stabilize From monofilaments of this type, they then obtain the bristles, cutting them to the desired length. As a rule, monofilaments, as well as sows, They show a circular section. For special use purposes sows with another section are also known, for example oval or polygonal. The monofilament is then extruded with a profile correspondent.

In many cases it is desirable to use bristles with a fibrous structure, especially fine fibers, at the end of use This is true, for example, for the type of products of sows that are intended for the application of media on surfaces or the like, such as brushes. Even in the if a frisada structure is sought, the sow has to be of fine fibers. In recent times it has also settled in dental medicine the recognition that the bristles Conventional toothbrushes have an effect of insufficient cleaning, since they do not penetrate the fine fissures of the surface of the tooth but glide over it. The analog is valid for the effect of cleaning in space interdental.

To maintain strong fibrous structures already has proposed to extrude the monofilament from mixtures of polymers The following effects are used for this: extrude and then stretch the monofilament, the polymer molecules are oriented in the longitudinal direction of the monofilament The primary liaison forces acting in the longitudinal sense are responsible for producing a high tensile strength. The longitudinal orientation of the molecules also provide the desired flexural elasticity. In the case of monofilaments made of a single polymer, the called secondary liaison forces, specifically the forces transverse to stretch, they are large enough to avoid fraying or unpacking the monofilament or The bristles In the case of monofilaments made from two mixed polymers, during stretching they form between the chains of molecules of the polymer zones of slippage, in which the secondary bonding forces are reduced A monofilament of this type or a bristle made of from it, it can be frayed by cutting tools by the effect of mechanical forces. The so-called "hairs" ("flags") that arise because of this have a very irregular, irregular section and cladding surfaces frayed. In a larger association of sows of this type achieves a filamentous structure that absorbs well, although hairs have uncontrolled resistance properties. I know tear, break or undo. Therefore, the bristles frayed in this grade are unsatisfactory, and for many application cases even inappropriate. The use in brushes of Teeth is worrying for hygienic reasons.

They are presented by a known embodiment of a bristle (WO97 / 14830) that has a core and a lining, which are manufactured by coextrusion of two different polymers. At the end of the use side of the bristle is mechanically removed or chemically the core material to form a sunken bag, You should pick up a toothpaste or paint. It is described also the formation of hairs ("flags") that are obtained fraying the lining material where it protrudes from the core. This fraying also occurs in a conventional manner by means of blades and, consequently, leads to them irregular structures

For that reason and especially for brushes teeth, bristles that are formed by a plurality of textile fibers similar to thin fibers and a coating surrounding the fibers (DE 94 08 268 U1). Coating and fibers can also be co-extruded as filament. After cutting to the length of the bristle, by mechanically worked or cut the liner at the end is removed of the bristle on the side of use, so that the fibers remain Free a short length. Regardless of expensive manufacturing of the bristles of this type, they can also be used only limited A major disadvantage is especially the sudden variation of the bending behavior in the transition zone from the fibers to the coating. If bristles of this type are used in applicators, surface damage may occur Due to the hard transition. The same applies to the use of bristles this type in toothbrushes in relation to the effect on teeth and gum. To this is added that the fibers are practically flexible, in such a way that in more indentations deep, interdental spaces or similar cannot penetrate, or not enough. In case of a permanent effort, the fibers They also break easily on the edge of the lining.

Interdental cleaners are also known (WO 96/39117) which are formed by coextruded monofilaments in geometric arrangement Each monofilament consists, at least, of two polymer components that on the limiting surface of two neighboring monofilaments lead to secondary bonding forces reduced By tensile forces in the axial direction, they eliminate secondary forces and a frayed structure of multiple fibers, similar to dental floss.

In the case of textile fibers, it is known (US-A-3 117 362) build Sharp-edged structures with silky shine, making it coextrusion in different polymers with a sectional shape suitable in each case, which adhere to each other on their surfaces limiting and that are separated by the addition of a solvent, which dissolves one of the polymers.

The invention aims to propose sows or interdental cleaners of a monofilament of at least two polymers that are extruded together. The bristles or cleft interdental cleaners have properties of reproducible resistance and form fins or slits that can defined according to number, shape and sizing. Further, with the invention a procedure for the manufacture of bristles or interdental monofilament cleaners of this type.

A sow that meets this goal with the characteristics of the definition of claim 1 are characterized according to the invention because the limiting surfaces they are limiting layers in which binding forces prevail reduced secondary and because the monofilament has a matrix made of a polymer that determines the physical characteristics and chemical of the bristle or interdental cleaner, and because the second polymer is included in the matrix in the form of layers thin that form the limiting surfaces.

Through the geometry of the limiting layers it can be determined in advance how, under the action of mechanical forces, the monofilament can be divided or split to an interdental cleaner or bristles made from disengagement monofilament. The slits or fins arise exactly in the contour prefixed by the geometry of the extruded Since the limiting layers extend in the direction length of the monofilament, each of the individual fins it has the same length and section in the entire length. By consequently, also the fins have properties of equal resistance, especially the same behavior to the flexion and the same tensile strength. But it is also possible to generate fins with different sections by modifying corresponding way the geometry. Since the monofilament or the bristle is split or split exactly into the limiting layers by the action of mechanical forces, through a form corresponding section fins can form in the facing surfaces that support the cleaning effect. Therefore, a sow divided in this way is also more effective on its coating surface than the bristles conventional. Due to the congruent forms, the sow is not Esparranca in excess. In a densely packed beam of bristles this type, each of the sows returns to take the form similar to a monofilament and the fins will develop their full effect by an axial or radial pressure. This can be well collected means and yield again by applying pressure.

This way you can make the bristles according to the invention, whose fins have the properties favorable of conventional bristles. On the other hand, at divide no thin parts are formed, or only to a very large extent small, so you don't have to subject the sow to a wide cleaning process. You get defined winged sows or split monofilaments defined for interdental cleaners in those who can avoid splitting or dividing deeply.

The matrix polymer, the same as the layers thin, it can be a copolymer or a mixture of polymers. The Advantages mentioned above are optimally achieved especially if the thin layers contain a part of the matrix polymers. In this case the polymer or the bristle will split by the action of a force in the weakest place, in concrete approximately in the center of the thin layer, though, due to the percentage of polymer corresponding to the matrix, the adhesion capacity of the residual layer on neighboring fins formed is large enough to prevent the appearance of thin parts.

The thin layers preferably have a thickness of some \ mum. Practical extrusion tests have proved that thin layers of this type can be coextrusion with the matrix polymer.

In thin layers may be present both polymers in equal parts.

The concrete realization of geometry comes determined by the desired characteristics of the bristles or the interdental cleaner In this way thin layers can arrive in the matrix to the perimeter of the monofilament, of such so that it can split or divide by acting a force relatively weak

Instead, it is possible that the layers thin end in the matrix at a certain distance from the perimeter of the monofilament. In this case you need to exercise a force majeure, although it is advantageous here that the fins emerged be of the matrix material also in the marginal zone, that is, that have the same wear characteristics as the siding of the bristles or fins.

The monofilament matrix may present possibly a third polymer, included in the matrix, that serves first to influence the characteristics of resistance of the fins emerged.

The monofilament may have the form usual circular in the bristles, but also a different section to the circular shape. Special mention must be made here of the sections polygonal, which in their cleaning action are more effective than round sections

Thin layers can become this case in corners of the polygonal section, in such a way that they arise relatively sharp edges with an angle of less than 90º.

Instead, thin layers can also transform into the surfaces of the polygonal section, being able to realize then songs with an angle within the scope of the 90º.

In a preferred embodiment, the matrix is of polyamide and thin layers are made of a polyolefin, especially polypropylene or polyethylene. This material pairing it has binding forces on the limiting surfaces large enough to prevent a tear or a split at the wrong time during the elaboration and use of the bristles However, with a directed and intense action of a strength, the union of polymers disintegrates.

The method according to the invention for manufacturing bristles from the monofilament described above are characterized according to the invention because the at least two polymers coextrusion to give a monofilament, the monofilament to the desired length of the bristles and, by mechanical forces action, the end of the use side is divided of the bristles transversely to the axis of these in a length limited along the limiting layers. Instead, both for the manufacture of the bristles as well as the cleaners interdental, you can proceed in such a way that they coextrusion at least two polymers to give a monofilament, and that after extrusion, stretching and eventually the stabilization the monofilament is cleaved by the action of mechanical forces transversely to the surface of the monofilament and in a locally limited length. Through the method according to the invention, in the coating of the monofilament can form fissured grooves that can serve for media collection. In the case of toothbrushes or of interdental cleaners, it would be about special dental hygiene products or dental preparations or antibacterials. For the rest, the monofilament of interdental cleaners get on the lining a increased roughness due to cracks.

From the monofilament mentioned above Dental cleaners of any length can be manufactured. The same measure can also be applied naturally to the sow elongated from the monofilament. The place of the cleft and the Extension of this can be adapted to the length of the bristle, to prevent the end of the sow from dividing or to favor it in a directed way. For example, you can divide only the end of the sow. The other indentations made in the lining they can serve, after the wear of the fins, to continue dividing the sow. Depending on the type and number of accumulated layers a corresponding number of fins arises at the ends of sow wear.

In the case of monofilament transformation in an interdental cleaner of any length, it is provided in the procedure that during the action of the mechanical forces, or after it, the monofilament is crushed. With it, the areas of elongated grooves or heels that delimit the grooves are facing outwards in the lining of the monofilament

The mechanical forces are preferably applied over most of the perimeter of the monofilament or the sow to ensure that they are applied on all the limiting layers of the polymer.

The monofilament crevices or the fissures of the bristles are preferably produced by forces of percussion. However, they can also be applied instead crushing or torsion forces. These forces can act in the cut sows or also simultaneously in groups of sows, for example in bundles of bristles, before or after their fixing to the bristle support of the brush.

Preferably, the bristles are rounded in their ends of the use side. This can happen before and / or after cleavage. In another preferred embodiment of the process, the different extremes arising after the split are endowed with a mark that indicates the useful length optically. This indicates to the user that after the bristle has worn out until the mark, that is, after wearing the cleft end, it Suddenly modify the characteristics of use, since then the whole bristle section acts, essentially more resistant to flexion The split ends also become increasingly Short and with it mechanically more aggressive. An indication of This type is particularly suitable if it is a brush teeth, body hygiene brushes or the like.

The invention is described below based on in the exemplary embodiments reproduced in the drawings. In These are shown:

Fig. 1 to Fig. 5 different sections of a monofilament;

Fig. 6 a view of a bristle with end split into the use side;

Fig. 7 a view of a bristle or a cleaner interdental with cleft lining;

Fig. 8 another variant of a section of a monofilament and

Fig. 9 a view of an interdental cleaner in A different embodiment.

The monofilament 1 according to Fig. 1 has a circular section and is manufactured by coextrusion of, as minimum, two polymers. It consists of a matrix 2, which is of a polymer that determines the properties of the bristle, and layers Thin 3 geometric included - in this case in the form of a cross- which are of a different polymer or of a mixture with the matrix polymer 2. In the area of thin layers 3 or of the limiting surfaces towards the matrix 2, the bonding forces secondary, that is, the transverse link forces to the longitudinal direction of the monofilament, are very small. In the indicated embodiment example, the thin layers 3 end on the coating surface 4 of the monofilament. Nevertheless, They can also finish a short distance before it.

As polymers for matrix 2 they are interested in special polyamides (PA), while thin layers 3 are, for example, of a mixture of PA / PP or PA / PE polymers.

In the exemplary embodiment according to Fig. 2, the thin layers 3 are included in matrix 2 in the form of a three-armed star, while Fig. 3 shows a monofilament 1 with a polygonal section, in triangular concrete. In this exemplary embodiment the thin layers included, which also here they extend from the center outwards, end in the corners of the polygon. In stead of, naturally they can also end on the surfaces that are Between the corners

In the exemplary embodiment according to Fig. 4, with the matrix 2 of monofilament 1 is coextruded another of several possible polymers, so that it is completely included in the matrix. It can be, for example, structures 5 in filament form that after the manufacture of the bristle and of split or split the same influence the behavior to the flexion or resistance of the fins that form.

Fig. 5 shows a flat monofilament 1 rectangular in which the thin layers 3 are arranged as weft, so that from the monofilament can a plurality of essentially rectangular fins are generated. The Fig. 8 finally shows a monofilament section in which the matrix 2 is formed by four equal external parts with section of circle sectors and a central core, delimited by 3 thin layers that run correspondingly.

In Fig. 6 the sow is shown schematically 6 which is manufactured from a monofilament by elongation, for example according to Fig. 2, and which is wound in its end of the use side by acting mechanical forces, such so that individual 7 fins arise whose shape equals the shape of the areas of the monofilament that form the matrix 2. It produce as many fins as parts where thin layers 3 divide the matrix 2. The length of use of the fins can be marked optically, for example by the transverse line indicated in Fig. 6.

In the exemplary embodiment according to Fig. 7, they act the mechanical forces on the surface of coating of a monofilament with a uniform separation or, in the case of a cut sow, at a certain distance from the end on the use side. Through the thickness of the layers and the degree of strength and / or accumulation / frequency of your application, you can get the lining of the monofilament or the bristle 6 only a locally defined length is torn and the slits 8, 9 and 10. These slits are found approximately online, specifically in the areas formed by the thin layers 3. In this embodiment, the grooves are torn in the ends of the bristle forming fins. As the Bristle wear fins constantly form.

A monofilament according to Fig. 7 can serve also in any length as interdental cleaner ("floss"), the slits being able to collect products from Dental hygiene, antiseptics or bactericides. For a cleaner interdental is also recommended to axially crush the monofilament as shown in Fig. 9, so that the steps 10 that delimit the slits can bulge towards the outside from the matrix polymer.

The matrix 2 or the polymer that the form can be of different colors in each of the section pieces delimited by thin layers.

Claims (29)

1. Sows (6) or interdental cleaners made of a monofilament (1) with reduced secondary bonding forces of at least two polymers jointly extruded in a geometrically regular arrangement, with limiting surfaces running essentially axially, where the bristles (6 ) or interdental cleaners are essentially cleft axially by the action of mechanical forces, characterized in that the monofilament has a matrix (2) of a first polymer that determines the physical and chemical characteristics of the bristles (6) or interdental cleaners , and because the second polymer is included in the matrix in the form of thin limiting layers (3), the reduced secondary bonding forces prevailing in the limiting layers (3) and the bristles (6) or interdental cleaners being able to split in the layers limiting 2. Interdental bristles or cleansers according to claim 1, characterized in that the matrix polymer is a copolymer or a mixture of polymers. 3. Interdental bristles or cleaners according to claim 1 or 2, characterized in that the thin layer polymer is a copolymer or a mixture of polymers. 4. Interdental bristles or cleansers according to claim 1 or 2, characterized in that the thin layers contain a percentage of the matrix polymer. 5. Interdental bristles or cleansers according to claim 4, characterized in that the two polymers are present in the thin layers in approximately the same proportion. 6. Interdental bristles or cleaners according to one of claims 1 to 5, characterized in that the thin layers have a thickness of a few µm. 7. Interdental bristles or cleaners according to one of claims 1 to 6, characterized in that the thin layers reach the perimeter of the monofilament in the matrix. 8. Interdental bristles or cleaners according to one of claims 1 to 6, characterized in that the thin layers end in the die at a certain distance from the perimeter of the monofilament. 9. Interdental bristles or cleaners according to one of claims 1 to 8, characterized in that the monofilament matrix has a third polymer included in the matrix. 10. Interdental bristles or cleaners according to one of claims 1 to 9, characterized in that the polymer of the matrix and that of the thin layers are of different colors. 11. Interdental bristles or cleaners according to one of claims 1 to 10, characterized in that the monofilament has a section that is different from the circular shape. 12. Interdental bristles or cleansers according to claim 11, characterized in that the monofilament has a polygonal section. 13. Interdental bristles or cleansers according to claim 12, characterized in that the thin layers reach the corners of the polygonal section. 14. Interdental bristles or cleansers according to claim 12, characterized in that the thin layers reach the surfaces of the polygonal section. 15. Interdental bristles or cleansers according to one of claims 1 to 14, characterized in that the matrix is made of polyamide and the thin layers contain a polyolefin. 16. Procedure for the manufacture of bristles from monofilaments according to one of claims 1 to 15, characterized in that the at least two polymers are coextruded to give a monofilament, because the monofilament is stretched, eventually stabilized and then cut to the desired length of the bristles, and finally the bristles are wound by the action of mechanical forces transversely to the limiting surfaces and to a limited length. 17. Procedure for the manufacture of bristles or interdental cleaners from monofilaments according to one of claims 1 to 15, characterized in that the at least two polymers are coextruded to give a monofilament, because the monofilament is stretched, eventually stabilized and finally the bristles are woven by the action of mechanical forces transversely to the limiting surfaces and to a locally limited length. 18. Method according to claim 17, characterized in that the monofilament is crushed longitudinally during or after the action of the mechanical forces. 19. Method according to one of claims 16 to 18, characterized in that the mechanical forces are applied at least on an essential part of the perimeter of the monofilament or the bristle. 20. Method according to one of claims 16 to 19, characterized in that the monofilament or the bristle is wound or split by means of percussion forces. 21. Method according to one of claims 16 to 19, characterized in that the monofilament or the bristle is wound or split by means of crushing forces. 22. Method according to one of claims 16 to 19, characterized in that the monofilament or the bristle is woven or split by torsional forces. 23. Method according to one of claims 16 to 22, characterized in that the end of the bristle use side is rounded before excision. 24. Method according to one of claims 16 to 23, characterized in that after the excision the end of the bristle use side is rounded. 25. Method according to one of claims 16 to 24, characterized in that the bristle is provided with a mark that optically signals the useful length of the various bristle fins obtained after cleavage. 26. Bristle products consisting of a fixed bristle and bristle holder, characterized in that at least a part of the bristles are manufactured from a monofilament according to one of claims 1 to 15 according to the method according to one of claims 16 to 25. 27. Bristle product according to claim 26, characterized in that the various ends of the cleaved bristles have a mark indicating the useful length. 28. Product of bristles in the form of an interdental cleaner, which is manufactured from a monofilament according to one of claims 1 to 17 according to the method according to claims 19 or 20, characterized in that the interdental cleaner is split at its perimeter with separations
regular. 29. Product of bristles according to claim
tion 28, characterized in that the interdental cleaner is sagging in the groove area due to crushing.