Patent Application
20240315436
The invention relates to a cosmetic brush unit comprising a bristle carrier according to the generic portion of claim 1, and to a cosmetic applicator comprising in most cases a stem and in all cases a corresponding cosmetic brush unit according to the generic portion of claim 11, and to a method of manufacturing the cosmetic brush unit according to the generic portion of claim 12.
Cosmetic brush units are part of a cosmetic applicator and are used to apply make-up and care products, which is referred to collectively as “make-up” below. To do this, the bristles are first wetted with the make-up. The make-up is then applied to the desired area with the help of the bristles. In the case of an eyelash brush, the bristles are first dipped into a container of mascara. Then, mostly after wiping the bristle covering, the eyelashes are mascaraed using the bristles residu-ally wetted with mascara. To do this, the cosmetic brush unit is brought into contact with the eyelashes with rotating and stroking movements.
Typically, cosmetic brush units designed as eyelash brushes can be divided into two categories that differ in the arrange-ment and material of their bristles.
Some have relatively many thin and soft bristles and are used to distribute mascara as evenly as possible on the lashes. Bristles with a low stiffness are advantageous for this. The bristles wetted with mascara then penetrate the spaces between the individual lashes when pressed against them, instead of pushing the lashes away. This distributes the make-up evenly along the lash line and makes the lashes appear more volumi-nous.
The other category of cosmetic brush units designed as eyelash brushes have fewer and especially stiffer bristles. They are used to make the eyelashes look longer. For this purpose, the bristles wetted with mascara are pressed against the base of the lashes in the area of the eyelid and then moved towards the free end of the lashes under constant pressure against the lashes. This straightens the lashes so that their free end is brought to a greater distance from the eyelid. This makes the lashes appear longer.
However, to achieve both effects in the best way possible, both cosmetic brush units have to be used, which is cumbersome and tedious.
In view of this, it is the object of the invention to provide a cosmetic brush unit with which the spaces between eyelashes can be evenly wetted with mascara and at the same time the eyelashes can be straightened.
According to the invention, this is solved with the features of the main claim directed to the cosmetic brush unit.
Accordingly, the solution to the problem is provided by a cosmetic brush unit having a bristle carrier in the form of at least two twisted wires. The twisted wires hold a plurality of filaments. These are clamped in such a way that each filament forms bristles extending outwards, preferably substantially radially. The bristles constitute a brush. The solution according to the invention is characterised in that the bristles—measured where their cross-section is monolithic and not di-vided-preferably have a diameter in the range from 0.076 mm to 0.3556 mm. All or at least some, preferably at least the majority of the bristles are divided into at least two, preferably at least four bristle fingers in the area of their free distal ends. Ideally the majority of the bristles shows not more than five bristle fingers.
Due to this shape of the bristles, the material of the filaments forming the bristles can be selected in such a way that when the bristles wetted with mascara are pressed against the eyelashes, the bristles are only slightly deflected in the area of their monolithic cross-section. The mascara-wetted bristles can then be pressed against the eyelashes in the area of the eyelid in such a way that the eyelashes are deflected in the direction of the eyelid. If the bristles are then moved towards the free end of the eyelashes under constant pressure, this leads to a straightening of the eyelashes. This makes the eyelashes appear longer.
The individual bristle fingers in the area of the free distal ends of the bristles, on the other hand, are deflected due to their reduced diameter in such a way that they penetrate into the spaces between the individual lashes. In addition, the reduced diameter of the bristle fingers facilitates their pene-tration into the spaces between the individual lashes. This ensures that the mascara is evenly applied to the spaces between the lashes. This makes the lashes appear more volumi-nous.
The term “filament” means a textile fibre and in particular a plastic fibre whose length exceeds its diameter by at least a factor of 10.
The term bristle finger refers to a region of a bristle that has a reduced resultant diameter and shares only a common root with the other bristle fingers of a bristle, but is not con-nected to the other bristle fingers in the region of its free end.
Furthermore, it is the object of the invention to provide a cosmetic applicator with which the spaces between eyelashes can be evenly wetted with mascara and at the same time the eyelashes can be straightened.
The solution to the aforementioned problem is provided by a cosmetic applicator with a handle and an inventive cosmetic brush unit as disclosed before. The cosmetic applicator is characterised in that a handle preferably adjoins the stem usually in the form of a closure cap for a cosmetic storage container.
To apply make-up, the cosmetic brush unit of the cosmetic applicator is first dipped into a cosmetic supply container so that the brushes of the cosmetic brush unit are evenly wetted with make-up. The cosmetic brush unit is then moved to the area where the make-up is to be applied. The cosmetic applicator is held by its handle.
It is further the object of the invention to provide a method of manufacturing a cosmetic brush unit according to the invention.
The solution to the above problem is provided by an inventive method of manufacturing the cosmetic brush comprising the steps of: a) first arranging the bristles between at least two wires; b) then twisting the at least two wires so that a portion of the bristles is held between the at least two twisted wires; c) then the tips of the bristles are beaten using a special striking tool preferably in the shape of a rotating wire brush, i. e. a brush carrying bristle covering formed bristles consisting of metal wires so that preferably each tip of the bristles is divided into at least two better at least four cross-sectional segments which are separated from each other in the region of their free ends and form at least four bristle fingers. The bristle covering of the rotating wire brush preferably has the shape of a cylinder, at least essentially.
This method of production allows the cosmetic brush unit, which combines the two categories of eyelash brushes described above, to be manufactured with little effort.
There are a number of ways in which the invention can be designed to further improve its effectiveness and usefulness. Thus, it is particularly preferred that the at least four bristle fingers make up at least 10% of the total length of the bristle to which they belong. Even better, the bristle fingers make up at least 20% of the total length of the bristle to which they belong. This is clearly preferred but shorter bristle fingers could be a matter of choice for some particular applications, too.
This ensures that the bristle fingers have a noticeably lower stiffness compared to the rest of the bristle section.
Another preferred embodiment is that the at least four bristle fingers extend above their root side by side in diverging di-rections. In this case, the bristle fingers are separated from each other by essentially V-shaped gaps.
This leads to the bristle fingers having a very low stiffness in the area of their free ends. Towards the root, the stiffness of the bristle fingers increases continuously.
This means that the bristle fingers are only deflected in the area of the free ends when the bristles are pressed against the eyelashes. If, on the other hand, the bristle fingers had the same stiffness along their entire length, this would pos-sibly result in the bristle fingers not penetrating into the spaces between the lashes, but merely bridging over the spaces between several lashes.
In another preferred embodiment, the bristle fingers are grouped around a free central space. The cross-section of the free central space increases continuously, often essentially conically, in the direction of the distal end.
When the cosmetic brush unit is dipped into the make-up container, make-up enters the free centre space. The make-up is held there until the bristles come into contact with the eyelashes. The free central space thus serves as a reservoir for the make-up and its transportation. This has the advantage that the cosmetic brush unit does not have to be immersed so frequently in the make-up container and yet there is always enough make-up on the bristles.
Ideally, each bristle finger is stiff enough to essentially return to its original position after being deflected by a more than insignificant load.
Each bristle finger behaves like an elastic bristle. This prevents the individual bristle fingers from sticking or catching on each other. In addition, a certain stiffness of the bristle fingers prevents the bristle fingers from bridging over the spaces between several eyelashes when they are pressed against the eyelashes, instead of penetrating into the spaces.
The term “deflection due to a more than insignificant load” means in particular the deflection of the bristle fingers that occurs when the bristles are pressed against the eyelashes.
In another preferred embodiment, each bristle finger bears a beard of a plurality of substantially limp strands at its distal end.
With the help of the beard, which consists of a multitude of essentially limp strands, the make-up applied to the lashes with help of the bristles is spread evenly along the lashes.
The term “essentially slack” describes the property of the material not to return to its original position on its own after being deflected by a more than insignificant load.
In another preferred embodiment, each bristle finger has a substantially rounded lateral surface portion. This lateral surface portion is mostly continuously convex in the circumferential direction. In addition, each bristle finger has two substantially non-circular lateral surface portions. These are preferably substantially straight. The substantially straight lateral surface portions meet along a line. In the direction of the substantially rounded lateral surface section, the substantially rounded lateral surface sections diverge or diverge from each other. Preferably, said lateral surface sections together form the entire lateral surface.
The cross-sectional area of the individual bristle fingers thus forms a pie-cut-like geometry.
The edge of each bristle finger formed in this way enables the bristle finger to penetrate the space between two lashes like a wedge. In this way, the lateral surfaces of the individual lashes adjacent to the respective gap are ideally coated with make-up.
Ideally, the bristles are made of or contain a polymeric material. This is ideally polyamide.
The choice of polyamide as the material for the bristles makes it possible to produce the bristles as fibres by melt spin-ning. This allows the bristles to be mass-produced at low cost.
Ideally, the bristles have a Shore D hardness in the range of 55 to 85 and preferably from 70 to 85. The Shore D Hardness measurements should be performed according to the standards ASTM D2240, ISO 868.
This allows the cuts—being mandatory or at least recommended to form the bristle fingers—to be made easily and the bristles still have sufficient hardness for the intended use.
Preferably, the at least two twisted wires are made of stainless steel. Each of the at least two twisted wires has a diameter in the range of at least 0.4 mm to preferably 0.9 mm.
The good formability of stainless steels enables cost-effec-tive production. The corrosion resistance also ensures a long service life of the cosmetic brush unit. With the diameters mentioned, the bristle carrier formed by the twisted wires has a relatively small overall diameter. This is advantageous for the manageability of the cosmetic brush unit or the cosmetic applicator during make-up application.
The mode of operation of the invention is described by way of example using
The bristle carrier 2 consists of two wires 3 twisted together. The bristles 4 are held on the bristle carrier 2 by being clamped between the twisted wires 3. For this purpose, the bristles 4 were placed between the two wires 3 before the twisting of the wires 3 and held there during the twisting process. The free ends of the bristles 4 protrude in a radial direction from the bristle carrier 2. The bristles 4 have a constant length over approximately two thirds of the length of the bristle carrier 2, so that in this area a cylindrical bristle set or a cylindrical brush section may result. In the area of the last third of the bristle carrier 2, the length of the bristles 4 can continuously be reduced. In this area, the result is then a truncated pyramid-like bristle trim or truncated pyramid-like brush section.
In the region of a certain axial axis section of the bristle carrier 2, the bristles 4 are not arranged uniformly around the bristle carrier 2 in the circumferential direction. Ra-ther, the bristles 4 are arranged helically around the longi-tudinal axis of the bristle carrier 2.
The bristle carrier 2 protrudes at one end beyond the bristle set formed by the bristles 4, i.e. is not occupied by bristles 4 along a section. This section of the bristle carrier 2 serves to connect the cosmetic brush unit to a handle of a cosmetic applicator, see
Between the edges of the individual bristle fingers 5 formed in this way is a free central space 6 with a circular cross-section. The diameter of the free central space 6 decreases, in most cases continuously, from the free end of the bristle fingers 5 to the value 0, so that the bristle fingers 5 merge into each other or into the bristle 4. The area where the bristle fingers 5 merge into the bristle 4 forms the root 7 of the individual bristle fingers 5.
There is a gap 11 between each two facing, essentially flat lateral surface sections 10 of two bristle fingers 5. The gap thickness of the gap 11, measured orthogonally to the essentially flat lateral surface sections 10, also decreases continuously from the free end of the bristle fingers 5 to the root 7 to the value 0. This results in a V-shaped geometry of the gap 11 in the side view of the bristle 4.
A beard 8 is also attached to the free ends of each bristle finger 5, which consists of a plurality of individual strands of the bristle finger 5, see
| Number | Date | Country | Kind |
|---|---|---|---|
| 21186171.1 | Jul 2021 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/069649 | 7/13/2022 | WO |
