Cosmetic brush comprising bristles having external depressions
A cosmetic brush and a process of making same. The brush comprises a substantially longitudinal stem and a plurality of bristles, each bristle extending from a base associated with the stem and terminating with a free end, each bristle having external walls and a longitudinal axis, the brush further having a major axis disposed along the stem, wherein the plurality of bristles comprises selected bristles, each of the selected bristles having at least one external depression oriented in a direction substantially parallel to the longitudinal axis of the selected bristle. The process comprises the steps of forming a hollow stem from a first moldable material; providing a plurality of bristle-forming channels surrounding and abutting the hollow stem, each of the bristle-forming channels, the plurality of bristle-forming channels comprising selected bristle-forming channels having at least one protuberance; injecting a second moldable material into the hollow stem under pressure sufficient to rapture the hollow stem in predetermined locations corresponding to the bristle-forming channels and to fill the bristle-forming channels with the second moldable material; and solidifying the second moldable material.
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This application claims the benefit of Provisional Application Ser. No. 60/615,864, filed Oct. 1, 2004.
FIELD OF THE INVENTIONThe present invention relates to a cosmetic brush, and more specifically, to a brush comprising bristles having external depressions.
BACKGROUND OF THE INVENTIONPlastic brushes are known in the art. Several international applications describe brushes made by the injection molding process and the processes therefore. Examples include: WO 02/03831 A1, titled Method and Device For Producing Bristle Products and Bristle Products; assigned to Coronet-Werke GmbH of Germany, German patent application DE 10201635.6, titled Method and Device For the Production of Bristles, assigned to Coronet-Werke GmbH of Germany; German patent application DE 10212701.8, titled Bristle, Method and Device For Its Production and Bristle Product, assigned to Coronet-Werke GmbH of Germany; and German patent application 10221869.2, titled Method of Manufacturing a Bristle Structure on a Carrier, assigned to Coronet-Werke GmbH of Germany, the disclosures of all of which are incorporated herein by reference.
Generally, plastic brushes can be made by a two-step process. First, a hollow core having a multiplicity of orifices through its surface can be formed from a first plastic material. Second, a second plastic material can be injected, under pressure, into the hollow core, so that the escaping (or “extruded”) through the recesses soft plastic forms individual bristles as the second material solidifies. The first and second materials can be identical, or different. The position of the orifices and their shapes can be chosen to define the position of the bristles and their cross-sectional configuration.
Now, it has been discovered that cosmetic brushes, such, for example, as those used for mascara application to eye lashes, can be improved by providing, at least partially, individual bristles that have a concave portion thereon. It is believed that such a brush will deliver a more refined application of liquid mascara to the lashes and reduce the potential for the lashes to “stick” to one another when the liquid mascara is applied to the lashes.
Accordingly, the present invention provides a cosmetic brush comprising a plurality of bristles, wherein selected bristles have at least one external depression oriented in a direction parallel to the longitudinal axis of the selected bristle, and the process for making such a brush.
SUMMARY OF THE INVENTIONA cosmetic brush of the present invention comprises a substantially longitudinal stem and a plurality of bristles extending therefrom. Each bristle has a base associated with the stem and a free end opposite to the base. Each bristle has external walls and a longitudinal axis oriented along the length of the bristle. The walls of the bristle can be concave, round, planar, or convex. The brush as a whole has a major axis disposed along the stem of the brush.
According to the present invention, at least some of the bristles, termed herein as “selected bristles,” have at least one external depression in their walls. The depression of each of the selected bristles is oriented in a direction substantially parallel to the longitudinal axis of the bristle.
The selected bristle can have any suitable shape in its cross-section perpendicular to the bristle's longitudinal axis. For example, the selected bristle can have a cross-section that includes oblong, polygon, circular, curbed, rhombic, trapezoid, or any other shape.
The number of the depressions per bristle can also vary. For example, the bristle can have on, two, three, four, and more depressions. In one embodiment, the depression or depressions extend through the entire length of the selected bristle. In another embodiment, the depression or depressions extend only through a portion of the selected bristle. In still another embodiment, the depression is located at the free end of the selected bristle.
In the selected bristles having more than one depression, the location of the depressions may vary. For example, in the selected bristles having two depressions, the depressions can be located opposite to each other. In the selected bristle having three or four depressions, the depressions can be spaced substantially equidistantly from one another, as viewed in the cross-section perpendicular to the longitudinal axis of the selected bristle.
The bristles may have differential lengths. In one embodiment, for example, the lengths of the bristles are such that the ends of several bristles consecutively disposed next to one another, as viewed in a cross-section of the brush perpendicular to the major axis, form an imaginary line that is straight. In another embodiment, such a line can be concave or convex.
The bristles may be made to gradually taper from the base towards the free end. Alternatively, the bristles may have a generally uniform thickness (with the exception of the selected bristles cross-sections of which are at least partially affected by the longitudinal depression), or taper from the free ends towards the bases of the bristles.
In one embodiment, the ends of at least some of the bristles, either selected or otherwise, have concave depression. Those depressions are different and distinct from the depressions in the walls of the bristles, for the depressions in the free ends of the bristles are not disposed longitudinally in relation to the longitudinal axes of the bristles.
The longitudinal axes of the bristles and the major axis of the brush can be mutually perpendicular. The embodiment is contemplated in which those are not mutually perpendicular, i.e., the axes of at least some of the bristles and the major axis of the brush form an obtuse angle or angles therebetween.
The brush of the present invention can be made by a process that includes a so called “injection molding” technique, i.e., a process wherein a molten material is injected, under pressure, into a closed form having a cavity of a desired shape, to fill the cavity, cooled to solidify in the cavity, and released from the cavity. Several patents documents listed herein above and incorporated by reference describe the injection molding process in sufficient detail.
More specifically, the process for making the cosmetic brush of the present invention comprises the steps of forming a hollow stem from a first moldable material; providing a plurality of bristle-forming channels surrounding and abutting the hollow stem, each of the bristle-forming channels terminating with an end and having a length, the plurality of bristle-forming channels comprising selected bristle-forming channels, each of the selected bristle-forming channels having at least one protuberance therein; injecting a second moldable material into the hollow stem under pressure sufficient to rapture the hollow stem in predetermined locations corresponding to the bristle-forming channels and to fill the bristle-forming channels with the second moldable material so that the second moldable material assumes the shape of the bristle-forming channels; and solidifying the second moldable material disposed in the bristle-forming channels thereby forming the plurality of bristles of the brush being made, wherein the plurality of bristles comprises selected bristles formed in the selected channels and having at least one external depression thereon.
The protuberances can be disposed along the length of the selected bristle-forming channels and/or at the end of the selected bristle-forming channels, depending on a desired configuration of the bristles being formed. The bristle-forming channel can be formed, for example, by a plurality of plates disposed consecutively adjacent to one another, wherein mutually adjacent plates have surface patterns that form, in combination, a desired profile of the bristle-forming channel.
The step of forming a hollow stem from a first moldable material can be accomplished by injecting the first moldable material under pressure into a support form structured to form the hollow stem. The first moldable material and the second moldable material may be identical or, alternatively, may differ from one another.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 3 to 6 are perspective views of various embodiments of the selected bristles of the brush of the present invention.
The embodiment of
According to the present invention, at least some of the bristles 50 have at least one external depression 120 in their walls. These bristles are termed herein as “selected bristles,” because the process of the present invention (described herein below) allows one to design what bristles should be structured to have at least one external depression. The depressions of the selected bristles can be oriented in a direction parallel to the longitudinal axes B of the bristles, or, alternatively or additionally, can be disposed at free ends of the bristles.
Bristles 50 can comprise bristles having a generally round cross-section (
The number of the depressions 120 per the selected bristle can vary. For example, the selected bristle can have one, two, three, four, and more depressions 120. In the selected bristles having more than one depression 120, the location of the depressions may vary. For example, in the selected bristles having two depressions 120, the depressions can be located opposite to each other,
The bristles 50 may have differential lengths. In one embodiment, for example, the lengths of the bristles 50 are such that the ends of several bristles consecutively disposed next to one another, as viewed in a cross-section of the brush perpendicular to the major axis A, form an imaginary line that is straight (
The bristles 50 can be made to gradually taper from the base towards the free end (
In one embodiment, the ends of at least some of the bristles 50 have concave depression 110,
The longitudinal axes B of the bristles 50 and the major axis A of the brush 10 can be mutually perpendicular. The embodiment is contemplated, however, in which those are not mutually perpendicular, i. e., the axes B of at least some of the bristles 50 and the major axis A of the brush 10 form acute or obtuse angle or angles therebetween (not shown).
The brush of the present invention can be made by using a technique known as “injection molding.” Injection molding is, in essence, a process wherein molten plastic is deposited under pressure, or injected, into a closed form having a cavity of a desired shape, to fill the cavity, then cooled to solidify in the cavity, and then released from the cavity. One skilled in the art will appreciate that using the injection molding process, it is possible to form virtually any desired configuration of the bristles, including the selected bristles of the present invention. In addition, the injection molding technique allows one to control the length of individual bristles, so that trimming of the finished brush may not be needed in order to form a certain cross-sectional profile of the brush, as shown, for example, in
The brush of the present invention can be made by an injection-molding process, for example, using a multi-component molding injection machine 200, schematically shown in
A plurality of bristle-forming channels 250 is provided. The bristle-forming channels 250 are disposed so that their entrances abut the hollow stem 260 in predetermined locations in which the bristles 50 of the brush being constructed should be disposed after the brush has been constructed. The overall configuration and geometry of the bristle-forming channels 250 corresponds to the desired overall geometry and configuration of the brush being made. Each of the bristle-forming channels 250 terminates with an end and has a predetermined length. Depending on the size and length of the bristle-forming channels 250, the bristle-forming channels 250 can be made by any means known in the art, for example using conventional drilling techniques, laser, chemical erosion, wire electrical discharge machine (EDM), or any other suitable means. The bristle-forming channels 250 can be formed, for example, by a plurality of coated plates 300 (
In accordance with the present invention, the plurality of bristle-forming channels 250 include selected bristle-forming channels 250a, i.e., the channels that are structured to form the selected bristles having at least one external depression 120 thereon, as described herein above. For this purpose, each of the selected bristle-forming channels 250a has at least one protuberance 290 therein. The protuberance or protuberances 290 can be disposed along the length of the selected bristle-forming channel 250a, at the end of the selected bristle-forming channels 250a, or both, depending on a desired configuration of the selected bristle being formed.
In the next step, a second moldable material 270 is injected, under pressure, into the hollow stem, to form the bristles (
After the second moldable material 270 solidify in the bristle-forming channels 250, the brush comprising the stem 260 and the plurality of bristles 50 extending therefrom can be released from the injection machine. If the plurality of plates 300 is used to form the bristle-forming channels 250, the plates 300 can be moved apart from one another, thereby releasing the formed bristles 50.
If desired, an optional step of injecting a third moldable material 280 (
All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is, therefore, intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
Claims
1. A cosmetic brush comprising a substantially longitudinal stem and a plurality of bristles, each bristle extending from a base associated with the stem and terminating with a free end, each bristle having external walls and a longitudinal axis, the brush further having a major axis disposed along the stem, wherein the plurality of bristles comprises selected bristles, each of the selected bristles having at least one external depression oriented in a direction substantially parallel to the longitudinal axis of the selected bristle.
2. The brush according to claim 1, wherein the selected bristle has a generally oblong shape in a cross-section perpendicular to the longitudinal axis of the selected bristle.
3. The brush according to claim 1, wherein the external walls of the at least some bristles comprise a surface selected from the group consisting of a flat surface, a convex surface, a concave surface, or any combination thereof.
4. The brush according to claim 1, wherein the at least one external depression extends from the base of the selected bristle to the free end thereof.
5. The brush according to claim 1, wherein the at least one external depression extends from the base of the selected bristle toward the free end thereof but does not reach the free end of the selected bristle.
6. The brush according to claim 1, wherein the at least one external depression extends from the free end of the selected bristle toward the base thereof but does not reach the base of the selected bristle.
7. The brush according to claim 1, wherein the at least one external depression is disposed intermediate but reaches neither of the base and the free end of the selected bristle.
8. The brush according to claim 1, wherein the bristles have differential lengths.
9. The brush according to claim 1, wherein the ends of at least three bristles consecutively disposed next to one another in a cross-section of the brush form a line selected from the group consisting of a straight line, a concave line, a convex line, or any combination thereof, the cross-section of the brush being perpendicular to the major axis.
10. The brush according to claim 1, wherein at least some of the bristles gradually taper from the base towards the free end.
11. The brush according to claim 1, wherein the free ends of at least some of the bristles have a concave depression therein.
12. The brush according to claim 1, wherein the longitudinal axes of at least some of the bristles and the major axis of the brush are mutually perpendicular.
13. The brush according to claim 1, wherein the brush is made by a process including injection molding.
14. A process for making a cosmetic brush comprising a substantially longitudinal stem and a plurality of bristles extending therefrom, the process comprising steps of:
- (a) providing a hollow stem from a first moldable material;
- (b) providing a plurality of bristle-forming channels surrounding and abutting the hollow stem, each of the bristle-forming channels terminating with an end and having a length, the plurality of bristle-forming channels comprising selected bristle-forming channels, each of the selected bristle-forming channels having at least one protuberance therein;
- (c) injecting a second moldable material into the hollow stem under pressure sufficient to rapture the hollow stem in predetermined locations corresponding to the bristle-forming channels and to fill the bristle-forming channels with the second moldable material so that the second moldable material assumes the shape of the bristle-forming channels;
- (e) solidifying the second moldable material disposed in the bristle-forming channels thereby forming the plurality of bristles of the brush being made, wherein the plurality of bristles comprises selected bristles formed in the selected channels and having at least one external depression thereon.
15. The process according to claim 14, wherein in the step of providing a plurality of bristle-forming channels, the protuberances are disposed along the length of the selected bristle-forming channels.
16. The process according to claim 14, wherein in the step of providing a plurality of bristle-forming channels, the protuberances are disposed at the free end of the selected bristle-forming channels.
17. The process according to claim 14, wherein the step of providing a plurality of bristle-forming channels comprises a step of providing a plurality of plates disposed side-by-side consecutively in an abutting relation to one another, wherein mutually abutting plates have surface patterns that form, in combination, a desired profile of the bristle-forming channels.
18. The process according to claim 14, wherein in the step of forming a hollow stem from a first moldable material and in the step of injecting a second moldable material, the first moldable material and the second moldable material are identical.
19. The process according to claim 14, wherein in the step of forming a hollow stem from a first moldable material and in the step of injecting a second moldable material, the first moldable material and the second moldable material differ from one another.
20. The process according to claim 14, further comprising a step of filling the hollow stem with a third moldable material.
Type: Application
Filed: Sep 29, 2005
Publication Date: Apr 6, 2006
Applicant: The Procter & Gamble Company (Cincinnati, OH)
Inventors: Norbert Dumler (Ansbach), Paul Sheppard (New Freedom, PA), Bryan Kadlubowski (Manchester, MD), Bernard Fellner (Ansbach)
Application Number: 11/238,361
International Classification: A45D 40/26 (20060101); A46B 1/00 (20060101);