The present invention relates to a toothbrush.
Several methods of making brushes are known. Conventionally, a brush body is provided with an array of holes corresponding to the desired array of bristles. Bundles or tufts of bristles are then inserted into the holes of the brush body and anchored therein by means of pressed-in small metallic anchors or by means of loops.
In an alternative method of making brushes, which has gained acceptance within just a few years and is referred to as AFT method (Anchor Free Tufting), the tufts of bristles are attached to a carrier platelet without loops or anchors, and the carrier platelet is then installed in or attached to a brush body. The carrier platelet may be connected with the brush body by injection molding or welding. The carrier platelet is provided with holes corresponding to the desired hole pattern. The tufts of bristles are inserted into the holes, with the bristle tufts projecting from a surface of the carrier. The bristles have attachment ends that slightly project on the opposite surface of the carrier. A heated stamp is pressed against the projecting attachment ends of the bristle tufts, the stamp causing the ends of the bristle tufts to be fused together and shaped to form a thickened knob, if desired. The ends of the bristles on the useful side may be pre-rounded or chemically provided with a point in advance. A suitable device for the attachment of tufts of bristles to carrier platelets for making brushes using the AFT method is disclosed in particular in EP 1 136 017 B1.
However, not all types of bristles can be processed using the AFT method. It is not possible to process, e.g., natural bristles or bristles made of or coated with TPE, specially structured bodies such as knobs or pegs, pointed cones made of TPE and the like, since these are not fusible.
The AFT method is also practically not suitable for processing chemically pointed bristles since the points of these bristles are so thin that because of their low inherent stiffness they tend to bend or buckle when they are inserted into the holes of the carrier platelet.
The present invention allows to make use of the advantages of the AFT method while nevertheless allowing to process natural bristles or specially structured bodies such as knobs, pegs or pointed cones as well as pointed bristles.
According to a first approach, the invention provides a toothbrush which comprises a brush body with a brush head and a carrier platelet attached to the brush head. A plurality of bristle bundles consisting of a thermoplastic material are attached anchor-less to the platelet. The brush head in addition has: bores, recesses or holes which have bristle bundles inserted and affixed with anchors or loops; and/or bores, recesses or holes which have knobs, pegs, pointed bristles or pointed cones inserted therein; and/or knobs, pegs, pointed bristles or pointed cones attached to the brush head.
According to a second approach, the invention provides a toothbrush comprising a brush body including a brush head having a plurality of recesses or deepened or raised mounting surfaces which each have one carrier platelet inserted therein or applied thereto and attached thereto, the carrier platelet having bristle bundles made of a thermoplastic material attached thereto without anchor, the bristle bundles of the different carrier platelets jointly constituting an array of bristles.
According to a third approach, the invention provides a toothbrush comprising a brush body including a brush head having at least one recess or a deepened or raised mounting surface having a carrier platelet inserted therein or applied thereto and attached thereto, the carrier platelet having bristle bundles made up of pre-pointed bristles made of a thermoplastic material attached thereto without anchor, which, following their attachment, having been given a completed pointed shape by means of a post-treatment.
Further features and advantages of the invention will be apparent from the description below and from the accompanying drawings to which reference is made and in which:
a and 4b each show one single chemically or mechanically pointed bristle in the AFT method; and
a and 5b each show one single chemically or mechanically pre-pointed bristle in the AFT method.
In the first embodiment of a toothbrush, shown in
Applying the same principle, structured bodies, in particular made of an elastomer material, in the form of knobs, pegs or pointed cones may be attached in holes or recesses of the brush body 10. In this way, it is possible to make use of the advantages of the AFT method while at the same time arranging natural bristles or structured bodies having any desired shape in the space for the bristles, which do not lend themselves to processing using the AFT method.
In the embodiment shown in
a and 4b illustrate the problems involved in the AFT method in the case of chemically or mechanically pointed bristles.
Number | Date | Country | Kind |
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20 2004 017 997.0 | Nov 2004 | DE | national |
20 2004 018 612.8 | Dec 2004 | DE | national |