AU4909899A

AU4909899A - Brush with a bristle holder and method for the production thereof

Info

Publication number: AU4909899A
Application number: AU49098/99A
Authority: AU
Inventors: Georg Weihrauch
Original assignee: Coronet Werke GmbH
Current assignee: Coronet Werke GmbH
Priority date: 1998-07-29
Filing date: 1999-07-13
Publication date: 2000-02-21
Anticipated expiration: 2019-07-13
Also published as: AU751933B2; UA72892C2; DK1100354T3; ATE241293T1; TR200100280T2; BR9912471A; HUP0102669A2; SK1412001A3; EG22152A; ZA200100322B; NO20010429D0; CZ2001310A3; PL345672A1; HUP0102669A3; EP1100354B1; PL193047B1; CA2338817A1; DE19834055A1; DE59905760D1; PT1100354E

Description

16.663.2 Translation of PCT/EP99/04900 as amended on May 15, 2000 BRUSH WITH A BRISTLE CARRIER AND METHOD FOR ITS MANUFACTURE The invention relates to brushes having a bristle carrier forming a handle and bristles fixed thereto, the bristle carrier having color contrasted areas. The invention also relates to methods for the manufacture of such brushes. 0 Brushes, particularly cleaningsand hygiene brushes, such as body brushes, toothbrushes, etc. are subject to widely varying stresses during use. They firstly consist of the permanent action of moisture, water, etc.. Moreover, as a function of the nature of the brush, there are the effects of 5 chemically and/or mechaniqally acting agents, such as washing agents, soaps, dentifrices, together with greases, paints, etc.. In addition, there are the holding and frictional forces exerted on the handle as a result of the user's hand. Toothbrushes, but also other hygienic and technical brushes are particularly exposed to such stresses. If the bristle carrier forming the handle of such a brush is to be provided with color contrasted areas, which have a design or informative function, this has hitherto taken place mainly by the following methods. A film carrying the color contrasted areas, e.g. the information is stuck on as a print (US-A-4,589,159). However, these films are rapidly detached, so that the design element or information is lost. Therefore 2 this procedure is completely unusable in practice. It is also known to apply such areas by film transfer pressure, namely in pre-stamped depressions of the bristle carrier. Although information applied in this way is somewhat more durable, detachment still takes place after some time and as a result the information content is lost as soon as parts of the information on the transfer film has become detached. Deformable films or layers (DE-A-4 207 755) introduced onto the bristle carrier which are stamped with the print, have UO the same disadvantages. Another method is the two-component injection molding procedure, in which the handle is made from one plastics material and the inscription from a different colored, other plastics material, which are injection molded in a two-stage process. This process is expensive due to the 05 costly injection molds. A change to the decorative or informative elements requires a very expensive storage of several molds or mold inserts and time-consuming setting-up work when changing. In addition, this process can only be used in the case of relatively large-area decorations or aO information with coarse line structure. It fails not only in the case of filigree contours and characters, but also if the surface area available for the information is small. For brushes having arbitrary uses, the problem of the aSE invention is to permit the application of durable information or decoration of any kind and to propose methods for the manufacture of such brushes.

3 AccordIng to a first variant of the invention, this problem is solved in that the plastics material of the bristle carrier, at least in the color contrasted areas is filled with laser beam-absorbing pigments reacting thereto with a 5 color change and that said areas are applied by laser beams to the bristle carrier. The problem is solved in a second variant in that the bristle carrier, at least in the surface-near area, comprises at *0 least two laminated plastics with different absorptivities for laser beams, whereof the upper layer with the lower absorptivity is transparent or translucent and the lower layer has the higher absorptivity, and that the color contrasted areas are applied by laser beams to the lower G layer reacting with a color change. As a result of the bristle carrier construction according to the two aforementioned vari-ants of the invention, the information can be applied by laser beams, which are C controlled in accordance with the contour of the optically contrasted areas and preferably in a computer-assisted manner. In the first variant, the laser beam-absorbing pigments react with a color change at the irradiated points. In the second variant the laser beams are absorbed at the 5~ interface between the two plastics layers and the desired color change occurs there and is rendered visible through the transparent or translucent top layer. The plastics material of the top layer can also undergo molecular restructuring by reflection at the interface, so that an even greater contrast 4 is obtained. Color contrasting areas applied in this way are not impaired by chemical or mechanical stresses, such as occur when using brushes. They are permanently maintained and are not detached from the bristle carrier. The color 5 contrasted areas can have a small surface, filigree form, which was not possible with the known methods. The color contrasted areas can be of different types and can e.g. relate to information of different contents, e.g. O ordering information, which can be used in the mass production of different brushes as sorting and packing information. In this case the information can be used in conjunction with the color or image recognition equipment for the automation of the transportation and packaging functions. The information can also indicate to the user characteristics of the brush or can be operating instructions. For example, brushes which are only to be used in the industrial sector for specific purposes as a result of the hygiene regulations O and which were hitherto marked by different paints or dyes, can now be differentiated by indelible inscriptions. Reference is made in this connection to brushes for hospitals, which must be differently marked for areas such as the kitchen, operating and treatment rooms, as well as wards. The brush construction according to the invention reveals its advantages in a particularly apparent manner in the case of toothbrushes. The latter are subject to high hygienic requirements, because they have to be used in the mouth and 5 are exposed there to additional stresses. This more particularly applies wit$ toothbrushes for children, in which the head is not only exposed to the aforementioned influences, but is frequently also stressed by uncontrolled or undesired chewing movements. Thus, hitherto the information on toothbrushes has largely been limited to the reproduction of a trademark, the name of the manufacturer, etc. and such information can only be located on the handle which does not come into contact with the mouth. LO In the case of a toothbrush the invention makes it possible to provide the information both on the handle and on the head, because the information cannot be impaired or detached by the indicated influences. Thus, on the handle and/or head of the toothbrush can be marked with a use-important characteristic, e.g. the hardness of the bristles (hard, medium or soft). Details can also be given on the use period, within which a perfectly satisfactory dental care is guaranteed, together with warning information. The latter is ~20 necessary, because in modern dental care toothbrushes are adapted from the design and material standpoints to different requirements and the toothbrush designed for a particular purpose may damage the teeth or gums in some other application. Hitherto all information necessary for the use of the toothbrush only appeared on the pack. On removing the toothbrush from the pack and using the same, such information has been lost, so that on repeat purchase or reordering the 6 user has no longer known which toothbrush he previously used. This significant shortcoming is avoided by the invention. In the same way sorting and packing information can be applied, which allow an automatic sorting and packing or the combination of ranges in connection with the mass production of different toothbrushes. All the aforementioned advantages are obtained in the same way in a third variant of the invention, in that the bristle carrier, at least in the surface-near area, comprises two laminated, differently colored plastics and that the top layer is removed by laser beams,, accompanied by the formation of the color contrasted area. The removal of the top layer takes place by melting and gasifying the plastics material forming it, so that the differently colored plastics material below the top layer is exposed. The information is advantageously applied to the readily visible surfaces of-the handle, i.e. in the case of a toothbrush on the underside facing the bristles and/or on the top of the handle remote from the bristles. Particularly in the case of hardness information, such information can also be applied to the toothbrush head, which was hitherto impossible for technical and also hygienic reasons. The invention also relates to a sales unit comprising a brush, particularly toothbrush of the aforementioned construction and a pack having color contrasted areas 7 receiving the same and which is at least partly made from plastic. According to the invention, in the case of such a sales unit, the pack is at least partly made from a laser absorbing plastics material reacting with a color change or is coated with such a material and the color contrasted. areas are applied by laser beams. Packs of the aforementioned type are mainly constructed in blister pack form, the transparent blister part being applied to the cardboard support and the latter carries the necessary information and desired, decorative elements. In the case of the sales unit construction according to the invention the information or decorations are produced on the pack in the same way as on the brush. The information on the toothbrush can at least partly coincide with the information on the pack. The coinciding information appearing on the pack and the toothbrush can in particular be decisive when making a repeat ZO purchase or when reordering, so that the 'consumer, even after removing the toothbrush from the pack, can' be sure that he will receive the same toothbrush on making a repeat purchase or reordering. For the mass production of toothbrushes with subsequent packing line, the laser instruments for the AS inscription of the toothbrush and the packing can be controlled by means of corresponding and optionally also partly identical programs.

8 The invention also relates to methods for the manufactu e of brushes having the aforementioned construction, where the bristle carrier is produced by molding, particularly injection molding, and the bristles are fixed during molding 5 by e bedding in the plastics material or subsequently to the bristle carrier. The manufacture of toothbrushes by injection molding has nowadays reached a level of perfection such that several thousand brushes can be produced hourly in the production line. The finishing of such brushes with color contrasted areas is impossible or is only possible with output or quality losses in the hitherto known methods. The label-like application of film prints is not possible with the reliability with which the brushes leg\re the injection molding machine and the same applies for film transfer prints. If the color markings are produced by two-component injection molding, apart from the high costs involved, this leads to a longer cycle time for the two-stage injection .O molding and the intermediately necessary transformation of the injection molded articles. In the case of the method according to the invention, the bristle carrier is molded from a plastics material, which is 25 filled with laser-absorbing pigments reacting to the laser beams by a color change and following the hardening of the plastics material the color contrasted areas are treated by correspondingly controlled laser beams up to the color change.

9 The laser treatment can be carried out at high speed, so that the hourly output of a production line is exclusively determined by the working cycle of the injection molding machine. Despite this high hourly output which can be 5~ achieved, the color contrasted areas can be produced with a arbitrary finesses and line configuration with a high degree of recognizability. The second variant of the brush according to the invention is DO implemented in that the bristle carrier is molded in an at least two-layer form, in that firstly a body is molded from a plastics material filled with laser beam-absorbing pigments reacting thereto with a color change and subsequently, at least on the color contrasted areas, is molded a top layer of a transparent or translucent plastics material with a lower absorptivity for the laser beams and "following the hardening of the plastics material, the color contrasted areas of the top layer are treated by means of correspondingly controlled laser beams up to the color citnge of the pigments in the .20 body. The third variant of the inventively constructed brush can be manufacture in that the bristle carrier is molded in at least two-layer form, in that firstly a body is molded from a af plastics material, then at least on the color contrasted areas is molded a top layer from a differently colored plastics material and following the hardening the color contrasted areas of the top layer are treated by means of 10 correspondingly controlled laser beams until the plastics material of the top layer has at least been sufficiently removed by melting and gasifyin 4 that the differently colored plastics material of the body is visible. All the aforementioned variants of the method are preferably performed in such a way that the mass produced brushes, following molding and hardening of the plastics material, are supplied to a laser station with at least one laser \0 instrument, where positioning takes place a d the colo contrasted areas are treated by means of at least -one correspondingly controlled laser beam. If the color contrasted areas cover a -large surface or are discreetly distributed on the bristle carrier, it is naturally possible to simultaneously dise several laser instruments. The methods according to the invention are particularly JO highly effective if the laser beam is controlled by a computer programmed in accordance with the color contrasted areas, it being advantageous for the computer to store several programs for differently configured, color cont rasted areas and for the programs, as desired, to be polled during X5 continuous brush manufacture. Thus, during continuous manufacture, it is possible to vary the information or decorations to be applied, e.g. corresponding sorting features for the subsequent pack ng 11 line or to combine brushes with different characteristics so as to provide ranges, which can be packed as a range ir the packing line. In conjunction with a corresponding design of the packing line with laser instruments, the described, T inventively constructed sales units can be produced and once again identical or partly identical information on the brush and pack can once again be stored in the computers of the laser instruments on the production and packing line. O The invention is described in greater detail hereinafter relative to embodiments of a toothbrush' ahdwith respect to the attached drawings, wherein show: Fig. 1 A view of the bristle-side underside of a toothbrush. Fig. 2 A view corresponding to fig. 1 of a different toothbrush embodiment. 20 Fig. 3 A view of the back of the toothbrush head. Fig. 4 A longitudinal section through the toothbrush of fig. 3 in the first variant and a larger-scale detail. Fig. 5 A longitudinal section of the toothbrush of fig. 3 in the second variant and a larger-scale detail.

12 Fig. 6 A longitudinal section of the toothbrush of Lig. 3 in the third variant and a larger-scale detail. The toothbrush shown in figs. 1 and 2 comprises a handle 1 and a head 2, which are interconnected by means of a more slender neck 3. Handle 1, head 2 and neck 3 are made from: plastic. The bristles 4 are fixed to the head 2. The handle 1 and optionally also the head 2 and neck 3 are 10 made from a plastic filled with pigments which, on laser irradiation react with a color change. By means of a correspondingly controlled laser, it is possible to apply a color contrasted area in the form of an information in an indelible and hygienically completely satisfactory'form to the handle 1 or head 2, namely on the back thereof. In the embodiment of fig. 1 said information 5 consists of a warning, namely to replace the toothbrush after a predetermined use period, said use period being indicated by ;XO a corresponding indicator on the bristles. In the embodiment according to fig. 2 an information 5 in the form of use instructions is applied. The toothbrush is mainly intended to remove dark plaque as a result of a special 1- construction of the bristle facing or the bristles, which advantageously takes place in conjunction with a corresponding dentifrice. Such a toothbrush will not be used for teeth which do not suffer from plaque.

13 In the embodiment according to fig. 3 information is applied to the back of the head 2 indicating the degree of hardness of the bristle facing, whilst the handle carries information indicating origin. The toothbrushes according to figs. 1 to 3 can be manufactured in accordance with the three variants of the invention. Fig. 4 shows the first variant, in which the bristle carrier comprising handle 1, head 2 and neck 3 is \O injection molded from a plastics material filled with pigments. These are pigments which react to the laser beams by a color change in the lighter or darker direction (positive or negative). In the larger-scale detail of fig. 4, the points at which the color change has taken place are 6 designated 6. In the variant of fig. 5 the bristle carrier comprising handle 1, head 2 and neck 3 is constructed in two-layer form. It comprises a body 7, which in particular provides the -MO necessary strength and use characteristics, and an injection molded-on top layer 8. The body 7 is made from a plastics material with a relatively high absorptivity for laser beams, whereas the top layer 8 has a lower absorptivity and is transparent or at least translucent. The absorptivity of the AS. plastic of the body 7 can once again be achieved by corresponding pigmenting. On irradiating with the laser the pigments react by a color change, indicated by reference numeral 9 in fig. 5. These can be light or dark contrasting 14 colors, which are visible through the transparent or translucent top layer 8. In the variant of fig. 6 the bristle carrier once again comprises a body 7 and a top layer 8. The injection molded body 7 is made from a differently colored plastic than the top layer 8. If the top layer is exposed to laser beams, they reflect back at the interface into the top layer and the plastics material of the top layer 8 is melted and gasified at the points encountered by the laser beams. These points are designated 10 in fig. 6. Thus, at these points the differently colored plastics material of the bristle carrier 7 is exposed and consequently provides the desired information in positive or negative form corresponding to the coloring of the plastics of body 7 and top layer 8.

Claims

1. Brush with a bristle carrier forming a handle and bristles fixed thereto, the bristle carrier having color contrasted areas,- characterized-in that the plastics material of the bristle carrier (1, 2, 3), at least in the color contrasted areas, is filled with aser beam absorbing pigments reacting subsequent ther-eto with a color change and that said areas are effected o7 the O bristle carrier using, laser beams.

2: Brush with bristle carrier forming a handle and bristles fixed thereto, the bristle carrier having color contrasted areas, charactbrizeds'in 'that the bristle carrier (1, 2, 3), at last in the surface-nar area, is made from at least two laminated plastics with different absorptivities for laser"beams, whereof theupper layer with the lower absorptivity is transparent or translucent and the lower layer has the higher absorptivity and that 20 the color contrasted areas are-effected on the lower layer reacting with a color ,change by means of laser beams.

3. Brush with a bristle carrier forming a handle and bristles fixed thereto, in which the bristle carrier has color contrasted areas, characterized in that the bristle carrier (1, 2, 3) , at least in the surface-near area, is formed from at least two laminated,, differently c cored 16 plastics and that the color contrasted regions are exposed by removing the cover layer using laser beams.

4. Brush according to one of the claims i to 3, particularly a toothbrush, whose bristle carrier comprises the handle (1) and a head (3), to which the bristles (4) are fixed, characterized in that the color contrasted areas are applied to the handle (1) and/or the head (3).

5. Brush according to claim 4, characterized in that the color contrasted areas are applied to the underside facing the bristles (4) and/or to the top side of the handle (1) remote from the bristles. 5

6. Brush according to one of the claims 1 to 5, characterized in that the color contrasted areas provide information.

7. Brush according to one of the claims 1 to 5, characterized in that the color contrasted areas form decorative elements.

8. Sales unit comprising a brush, particularly toothbrush, according to one of the claims 1 to 7 and a pack having color contrasted areas receiving the same and made at least partly from plastic, characterized in that the pack is at least partly made from a laser-absorbing plastic reacting with a color change and the color contrasted areas are applied by laser beams. 17

9. Sales unit according to claim 8, characterized in that the color contrasted areas on the brush are at least partly identical to the color contrasted areas on the pack.

10. Method for the manufacture of brushes according to one of the claims 1 and 4 to 7, in which the bristle carrier is produced by molding, particularly injection molding and the bristles are fixed to the bristle carrier during the molding operation by embedding in the plastics material or subsequently thereto, characterized in that the bristle carrier is molded from a plastics material filled with laser-absorbing pigments reacting thereto with a color change and following the hardening of the plastics material the areas to be color contrasted are treated by correspondingly controlled laser beams until the color changes.

11. Method for the manufacture of brushes according to one of 010 the claims 2 and 4 to 7, in which the bristle carrier is produced by molding, particularly injection molding and the bristles are fixed to the bristle carrier during molding by embedding in the plastics material or thereafter, characterized in that the bristle carrier is molded in an at least two-layer form, in that initially a body is molded from a laser beam-absorbing plastics material filled with pigments reacting thereto with a color change, then at least on the areas to be color 18 contrasted is molded a top layer of a transparent or translucent plastic with a lower absorptivity for the laser beams and following the hardening of the plastic the areas of the top layer to be color contrasted are treated by correspondingly controlled laser beams until the pigments in the body change color.

12. Method for the manufacture of brushes according to one of the claims 3 to 7, in which the bristle carrier is o0 produced by molding, particularly injection molding and the bristles are fixed to the bristle carrier during molding by embedding in the plastics material or subsequent thereto, characterized in that the bristle carrier is molded in an at least two-layer form, in that initially a plastics material body is molded and then at least on the areas to be color contrasted is molded a top layer from a differently colored plastics material and after hardening the areas to be color contrasted of the top layer are treated by means of correspondingly 210 controlled laser beams until the plastics material of the top layer has at least been removed to such an extent by melting and gasifying that the differently colored plastic material of the body becomes visible. S'

13. Method according to one of the claims 10 to 12, characterized in that the brushes manufactured in large numbers per unit of time, following the molding and hardening of the plastic are supplied to a laser station having at least one laser instrument, are positioned 19 there and the areas to be color contrasted are treated by means of at least one correspondingly controlled laser beam.

14. Method according to claim 13, characterized in that the laser beam is controlled by a computer programmed in accordance with the color contrasted areas.

15. Method according to claim 14, characterized in that the ja computer stores several programs for differently configured, color contrasted areas and the programs can be polled, as desired, during the continuous manufacture of the brushes.