WO2004060103A2

WO2004060103A2 - Applicator brush for a cosmetic product

Info

Publication number: WO2004060103A2
Application number: PCT/US2003/041371
Authority: WO
Inventors: John Kurek
Original assignee: Avon Products Inc
Current assignee: Avon Products Inc
Priority date: 2002-12-31
Filing date: 2003-12-23
Publication date: 2004-07-22
Anticipated expiration: 2005-06-30
Also published as: AU2003299964A1; AU2003299964A8; WO2004060103A3

Abstract

A brush having a central core with a proximal end adapted to be affixed to a handle means, a distal end defining a tip (24), and a twisted wire (20) holding a helical array of disposed bristles (25). The core has at least two zones, preferably three zones, wherein at least one zone differs in the range of bristles per turn of the helix from the other zone(s). One type of bristle is employed throughout the brush, and preferably the bristles are substantially uniform in diameter throughout the brush. A zoned picker bar is provided enabling production of bruses having a predetermined zoned configuration.

Description

Applicator Brush for a Cosmetic Product

BACKGROUND OF THE INVENTION

This invention relates to a brush for applying a cosmetic product. The invention particularly relates to a mascara brush having desirable application characteristics for applying mascara to the eyelashes. Preferably, the brush has at least two distinct zones, more preferably it has at least three distinct zones. The invention additionally relates to a process for producing such brushes and to a novel picker bar utilized in the process.

Eye makeup applicator brushes, particularly brushes for applying mascara to the eyelashes, are well known in the art. Generally, such brushes are produced by first bending a wire to form a U-shaped loop. Brush bristles retained within the grooves of a picker bar are then transferred to and disposed within and normal to the legs of the U- shaped wire loop. With the base, i.e., the open ends, of the U-shaped wire in fixed position, e.g., secured in a brush handle, the legs of the U-shaped wire are twisted to secure the bristles in place. Any excess bristle material is then trimmed.

Typically, prior art brushes comprise rows of bristles disposed around an axial core or support in a helical pattern, for example, the helix (or spiral) formed by the twisting of the wire as described above. The known brushes have various bristle configurations. Thus, brushes having bristles of different lengths homogeneously disposed along the axial core, or brushes with the bristles of different lengths forming a specific geometric configuration, e.g., a cone, elliptical or other shaped brush, are known.

US Patent No. 5,482,059 discloses a mascara brush comprising a twisted wire core extending longitudinally and a plurality of bristles mounted to the twisted wire core. The plurality of bristles comprise a middle cylindrical section containing a plurality of at least first and second different bristle types of relatively uniform length randomly intermingled throughout the length of the middle section. The brush also contains two end sections that contain a third type of bristle. The middle section is more densely packed than that of the two end sections.

US Patent No. 5,709,230 discloses a mascara brush comprising a twisted wire core that extends longitudinally and a plurality of bristles mounted to the twisted wire core. The plurality of bristles comprise a middle cylindrical section containing a plurality of at least first and second different bristle types of relatively uniform length intermingled throughout the length of the middle section and two end sections containing a plurality of bristles comprising one of the first or second bristle types. The middle section is less densely packed than at least one of the end sections.

The '059 and '230 patents disclose mascara brushes containing multiple distinct sections or zones throughout the length of the brush. The sections are distinguished by the diameter, length, stiffness, and density of the bristles found in each section. This results in a variation in overall effective stiffness from zone to zone. More than one type of bristle is employed in the mascara brushes of the '059 and '230 patents. Thus, the middle section of the brushes of the '059 and '230 patents each incorporate stiff (or large diameter) bristles of irregular cross-section and soft (or small diameter) bristles of circular cross-sections. The stiffness of the stiff bristles in the middle section of these brushes results in a non-spiral arrangement of the stiff bristles projecting from the wire.

US Patent No. 6,394,678 discloses a brush for applying mascara comprising an axially elongated twisted wire core having a proximal end, a distal end and a length therebetween, and a brush body that projects outwardly around the core over a substantial part of the length of the core. The brush body comprises at least one zone of fibers for combing eyelashes, such fibers being substantially non-absorptive to mascara, and at least one zone of material substantially absorptive to mascara. The zones are disposed in succession along the length of the core. Patentees teach that the absorptive material can be soft cotton fiber densely aggregated together. They further disclose that the absorptive zone can have a substantially higher density or number of fibers per turn of the core wire than the number of fibers in the non-absorptive zone or zones. US Patent No. 5,853,011 discloses a brush for application of a cosmetic product to keratinous fibers. The brush comprises an elongated core and bristles extending substantially radially from the core. The bristles define a part of a cylindrical envelope with a central axis. Bristles within the axial limits of the cylindrical envelope form at least one concave cutback and at least one crest zone on the cylindrical envelope. The width of the concave cutback varies along the length of the brush and the concave cutback has a single maximum width. Patentee discloses that the concave cutback can be situated in a zone with a low density of bristles while the end zones of the brush and the at least one crest zone can have a higher density of bristles.

PCT WO 95/17837 discloses a cosmetic product applicator brush that has a product application region and a lash separation region. The brush comprises an elongate stem having a distal end, a handle attached at the opposite end of the stem and a plurality of bristles extending generally radially from near the distal end of the stem, preferably at the distal end of the stem. The bristles of the brush in the product deposition section have a relatively low average bristle density, as compared to the average bristle density of the lash separation section. The average bristle length of the bristles within the product deposition section is relatively small, as compared to the average bristle length of the bristles in the lash separation section.

US Patent No. 4,887,622 discloses a brush for the application of mascara to the eyelashes. The brush comprises a center core formed from a twisted wire holding a helical array of regularly disposed bristles, with a bristle diameter of from 0.10 to 0.25 mm and with from approximately 10 to 40 bristles per turn of the helix. Patentee discloses that the bristles of the free end of the brush can be more densely arranged for making up the lashes of the lower eyelid. The patentee asserts that even deposition of the mascara on the eyelashes is obtained by reducing the number of fibers from the typically employed 50 to 60 bristles per turn, to 10 to 40 bristles per turn. The prosecution history of the '622 patent, makes it clear that "regularly disposed" means that patentee's brush has a constant number of bristles per turn of the helix. In other words, the '622 patent and its prosecution history makes clear that the brush, asserted to possess superior deposition characteristics, is made of a centrally disposed twisted wire core holding a helical array of regularly disposed bristles with approximately 10 to 40 bristles per turn of the helix, a bristle diameter of between 0.10 to 0.25 mm and a constant number of bristles per turn of the helix along the length of the brush.

SUMMARY OF THE INVENTION

The brush of the present invention comprises a handle, a central core that is a spirally wound U-shaped wire having a plurality of turns, the wire having free ends attached to the handle and a tip end distal of the handle, and a plurality of bristles of a single type held within and extending substantially radially from the central core, the bristles being arranged to provide at least two zones: a first zone having a predetermined range of bristles per turn and a second zone having a predetermined range of bristles per turn, wherein the predetermined range of bristles per turn in the first zone is greater than the predetermined range of bristles per turn in the second zone, and wherein the second zone is most distal to the handle. By "single type" is meant that substantially all of the fibers are approximately uniform in width and, preferably, in length as well.

In another embodiment, the brush of the present invention further comprises a third zone having a predetermined range of bristles that is less than or more than the predetermined range of bristles in the first zone, and which is proximate the handle. That is, the first zone of bristles is a middle zone situated between the second zone (distal the handle) and the third zone (proximate the handle). In a preferred embodiment, the first and third bristle zones have the same predetermined range of bristles per turn. In an alternative embodiment, each of the three zones has a different predetermined range of bristles per turn.

The present invention also comprises a unique picker bar comprising an elongated end having a front surface, a rear surface, and a top surface. The top surface comprises at least two zones, each zone having one or more grooves (or channels) adapted to receive bristles, each zone of the picker bar corresponding to a bristle zone of the brush of the present invention. Each groove of the picker bar zone corresponding to the first zone of the brush (i.e., the zone of the brush of greater range of bristles per turn) is characterized by having a greater cross-sectional area (as viewed from the front surface of the picker bar) than a counterpart groove in the picker bar zone corresponding to the second zone of the brush. This allows a groove of the picker bar located in the first zone to have a greater bristle fill capacity, which results in more bristles per turn in the first bristle zone.

Similarly, the picker bar may have a third zone (and additional zones) corresponding to the third bristle zone (and additional bristle zones) of the brush.

The process of making the brush of the present invention comprises placing a plurality of bristles of a single type within grooves of the picker bar of the present invention normal to the front surface thereof; providing a U-shaped wire having a closed end and two free ends, each of closed end and the free ends being held; transferring the bristles from the picker bar of the present invention to within the space defined by the U- shaped wire, and twisting the wire, whereby the bristles are held within the wire and extend substantially radially therefrom.

Further features and advantages of this invention will be apparent from the detailed description herein below set forth together with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be explained with reference to the drawings wherein:

Figure 1 is a side view of a mascara brush produced in accordance with the present invention through use of the picker bar of Figure 2. Figure 2 is a side view of a picker bar of the present invention used in producing the brush of Figure 1.

Figures 3 and 4 are side views of different embodiments of picker bars used in producing the brush of the present invention.

DETAILED DESCRIPTION

The brush 10 of the present invention shown generally in Figure 1 comprises handle 15, a central core that is a spirally wound U-shaped wire 20 having a plurality of turns 22, the wire having free ends 23 attached to the handle and a tip end 24 distal of the handle, and a multiplicity of bristles 25. The bristles 25 extend substantially radially from the wire 20. That is, the bristles 25 are generally normal to the wire 20.

The bristles contained in the brush of the present invention are arranged in at least two zones. In the embodiment illustrated in Figure 1, the brush 10 has bristles 25 arranged in three zones 30, 40, 50. As will be explained in more detail below, and as a consequence of the use of the picker bar 100 of the present invention shown in Figure 2 and described in detail below, bristle zone 40 is characterized as having a greater range of bristles 25 per turn than bristle zone 30 located at the tip 24 of wire 20. While bristle zone 30 may have a greater range of bristles per turn than bristle zone 50, preferably it is a smaller or an equal range of bristles per turn. Most preferably the range of bristles per turn in zone 30 is the same as present in zone 50.

The range of bristles per turn of the wire 20 in bristle zone 40, that is, in the bristle zone of high bristle density, is from about 50 to about 120 bristles, preferably from about 70 bristles to about 90 bristles, and most preferably from about 80 bristles to about 90 bristles, per turn. More than one bristle zone of high density may be incorporated into the brush 10 of the present invention. As explained below, it is permissible for each bristle zone, here the bristle zone 40 of high bristle density, to have variations in the number of bristles in each turn of the wire, provided that the number of bristles in each turn is within the predetermined range for that bristle zone. These turn-to-turn variations may be inherent in the manufacturing process, but can also be built into the manufacturing process by proper design of the picker bar 100.

Bristle zones 30 and 50 of brush 10 preferably have essentially the same range of bristles per turn, as a consequence of the design of the picker bar 100, described below. However, the range of bristles per turn in bristle zones 30 and 50 may differ. In the embodiment of the brush 10 shown in Figure 1, the range of bristles 25 in the bristle zones 30 and 50 is less than the range of bristles 25 present in bristle zone 40. Thus, bristle zones 30 and 50 are zones of less bristle density. The range of bristles 25 in each of bristle zones 30 and 50 is from about 20 to about 80 bristles, preferably from about 40 bristles to about 65 bristles, and most preferably from about 50 bristles to about 60 bristles, per turn.

Each zone of the brush generally has from 1 to 20, preferably 4 to 10, and especially 5 to 8, turns 22 of the wire 20. The brush 10 generally has 10 per 25 turns per linear inch, preferably 15 to 20 turns per linear inch.

It should be appreciated that as used herein "handle" is intended to encompass any device or implement adapted to hold the mascara brush and to enable the user to manipulate it for application of mascara to the eyelashes. For example, the brush can be affixed to the closure for a container adapted to hold mascara.

The terms "bristle" and "fiber" are used herein interchangeably and are intended to be synonymous.

Twisted wire, fiber mascara brushes of the present invention may be manufactured as follows: A spool of stainless steel wire generally having a diameter of 0.0240" to 0.0320" is bent and thereafter cut to form a "U"-shaped wire having two free ends and a closed tip end. The U-shaped wire is also referred to as a clip.

The U-shaped wire clip is received by collets that hold the open ends and the closed end of the U-shaped wire clip in such manner that the clip maintains an open configuration, i.e., an open space between the legs of the U-shaped wire clip. The open configuration is approximately 1/4" at the open end and 1/16" at the closed or bent end.

The brush bristles or fibers are stored in a fiber tower. The fibers are conventionally supplied in hank-form, i.e., the fibers are wrapped in a paper or plastic wrap with the hank diameter being approximately 1 3/4". The hank is manually cut into smaller sections or "pucks" which are approximately 1" in length. The pucks are loaded into the fiber tower and the wrapping material is removed leaving the fiber in the fiber tower in a flat horizontally stacked configuration.

A "picker bar" or "rake" is slid across the base of the fiber tower. A suitable picker bar for use in the process of making the brush of the present invention is picker bar 100 shown in Figure 2, which is a hardened steel bar approximately 11" long, 1/4" wide and 7/16" in diameter. The picker bar has a series of rectangular grooves or channels cut into one side of the bar. Conventionally, the grooves are equidistant in spacing and equal in width and depth. The picker bar 100, however, has grooves of different bristle fill capacity as described in more detail below.

With the picker bar 100 in position beneath the fibers in the fiber tower, the grooves then fill with bristles, the bristles being positioned in the grooves normal to the front surface of the bar.

The fibers are collected on the picker bar along its length, the distribution of fibers being related to the rill capacity of the grooves. The collection of fibers is then anchored in place captured with a fiber clip or clamp. The fiber clip then transfers the collection of fibers and inserts them into open space between the legs of the wire clip. Optionally, this fiber clip may be designed to replicate the fiber density differential along the length of the picker bar of this invention. In this regard, the fiber clip may also have corresponding grooves that coincide with the groove configuration of the picker bar. The fibers are then released from the fiber clip.

The collets holding the wire clip are rotated in opposing directions at speeds of approximately 100 to 250 rpm. As a consequence of the resultant twisting process, the wire clip is turned in a helical configuration, which captures the fibers and distributes them across a specified number of helical wire turns, with the fibers extending substantially radially from the wire. Following the twisting process, a cutter blade may extend to symmetrically shape the brush and cut the bristles ends. The brush is ejected from the collets and the process is repeated to produce further brushes.

The benefits of the present invention are achieved by use of the unique picker bar

(also known as a pick or rake). A picker bar of the present invention is shown in Figure 2. Picker bar 100 is an elongated metal, typically steel, bar having a front surface 110, a rear surface (not shown) that is a mirror image of the front surface and a top surface 115. A plurality of tooth-like grooves, generally identified by the numeral 120 that are uniform in depth through the width of the picker bar (from front surface 100 to the rear surface) are cut into the top surface 115.

The picker bar 100 can also be configured so that the tooth-like grooves are divided into two zones wherein at least one of the dimensions of width and depth of the grooves in one zone differs from that of the other zone.

As shown in Figure 2, the picker bar 100 can be divided into three groove zones; a middle zone 140 and two end zones 130 and 150. The groove zones 130, 140 and 150 of picker bar 100 correspond to the bristle zones 30, 40 and 50, respectively, provided in brash 10 shown in Figure 1. To provide the greater bristle density in bristle zone 40, each of the grooves 120b in groove zone 140 have a greater cross-sectional area than each of the grooves 120a and 120c in the groove zones 130 and 150, respectively. That is, the larger grooves 120b have a greater bristle fill capacity than the smaller grooves 120a and 120c.

Figure 1 illustrates a brash 10 produced utilizing the picker bar 100 of Figure 2.

Bristle zones 30, 40 and 50 of the brush 10 shown in Figure 1 are produced by and correspond to the groove zones 130, 140 and 150 of picker bar 100 of Figure 2.

By varying the width, depth and/or shape of the grooves in the picker bar across the length of the picker bar or in one or more zones on the picker bar, a brush can be produced that has one or more zones across the length of the brush, each zone having a desired predetermined bristle density. This is because wider or deeper grooves in the picker bar hold more bristles than narrower or shallower grooves. It is thus possible to vary the width, depth and/or shape of the grooves in the picker bar of this invention so that each picker bar groove will fill with the requisite number of bristles to form a brash having the desired predetermined configuration of bristle zones.

In Figure 2 the grooves 120a, 120b and 120c vary in width, but have the same depth. In Figure 3, the grooves 120e are both wider and deeper than grooves 120d and 120f. In Figure 4, grooves 120i are deeper than grooves 120h and 120g, and narrower than grooves 120h. The grooves 120h are wider than grooves 120g and 120i.

It is believed that anchoring means can optionally be employed so that when the U-shaped wire, with bristles inserted, is twisted through use of a first torque so as to produce a first predetermined number of turns, the twisted portion of the U-shaped wire is then anchored in position whereupon the remaining untwisted portion of the U-shaped wire is then subjected to a second torque, to produce a second predetermined number of turns using a second torque different from the first torque. In this fashion, by varying the torque one can adjust for the variance in the different number of bristles per turn in the zones along the length of the brush. The bristles employed in the production of the brash of the present invention are composed of the same material across throughout the brash. Preferred bristles are made of nylon and/or polypropylene. Other thermoplastic and elastomeric materials may also be used, as is known in the art. The bristles typically have a diameter of about 0.01 mm to about 0.50 mm, preferably about 0.10 mm to about 0.25 mm. Preferably, the bristles have substantially the same diameter. Substantially all of the fibers are absorptive to mascara.

It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the spirit of the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A brush for application of mascara to eyelashes comprising a handle, a central core having a proximal end affixed to the handle, and a distal end defining a tip, the central core being a spirally wound U-shaped wire, and a plurality of bristles of a single type held within and extending substantially radially from the central core, the central core having at least two bristle zones, a first zone having a predetermined range of bristles per turn of the spirally wound wire and a second zone adjacent the distal end having a predetermined range of bristles per turn of the spirally wound wire, the range of bristles per turn in the first zone being greater than the range of bristles per turn in the second zone.

2. The brash of Claim 1 , wherein the bristles are of substantially uniform diameter throughout the brash.

3. The brush of Claim 1 further comprising a third zone proximate the handle having a predetermined range of bristles per turn.

4. The brash of Claim 3, wherein the bristles are of substantially uniform diameter throughout the brash.

5. The brash of Claim 4, wherein the predetermined range of bristles per turn in the third zone is less than the predetermined range of bristles per turn in the first zone.

6. The brash of Claim 4, wherein the predetermined range of bristles per turn in the third zone is greater than the predetermined range of bristles per turn in the first zone.

7. The brush of Claim 1 , wherein the first zone has a range of about 50 to about 120 bristles per turn, and the second zone has a range of about 20 to about 80 bristles per turn.

8. The brash of Claim 7, wherein the first zone has a range of about 70 to about 90 bristles per turn, and the second zone has a range of about 40 to about 65 bristles per turn.

9. The brash of Claim 4, wherein the bristles have a diameter from about 0.01 mm to about 0.50 mm.

10. The brash of Claim 9, wherein the bristles have a diameter from about 0.1 mm to about 0.25 mm.

11. The brash of Claim 1 , wherein substantially all of the fibers are absorptive to mascara.

12. A method of making a brush for application of mascara to eyelashes, the method comprising:

a. Providing a picker bar having at least two zones, each zone having one or more grooves adapted to receive brash bristles, each groove in a zone having a preset bristle fill capacity, the preset bristle fill capacity of the one or more grooves in the first zone being greater than the preset bristle fill capacity of the one or more grooves in the second zone;

b. Placing a plurality of bristles in the grooves of the picker bar;

c. Providing a U-shaped wire having a closed end and two free ends, each of the closed ends and the free ends being held, with the free ends attached to a handle portion of the brush;

d. Placing the second_^zone of the picker bar distal to the handle portion of the brush and closest to the closed end of the wire; e. Transferring the bristles from the picker bar to within the U-shape defined by the wire; and

f. Twisting the wire to spirally wind the wire around the bristles.

13. A brash made by the process of Claim 12.

14. A picker bar for use in the manufacture of a brush for application of mascara to eyelashes, the picker bar comprising at least two zones, each zone having one or more grooves adapted to receive brush bristles, each groove in a zone having a preset bristle fill capacity, the preset bristle fill capacity of the one or more grooves in the first zone being greater than the preset bristle fill capacity of the one or more grooves in the second zone.