US20190246771A1

US20190246771A1 - Brush for applying a product to the eyelashes or eyebrows

Info

Publication number: US20190246771A1
Application number: US15/757,800
Authority: US
Inventors: Alain Berhault; Eric Caulier; Audrey Thenin
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 2015-09-08
Filing date: 2016-09-02
Publication date: 2019-08-15
Also published as: FR3040605A1; WO2017042103A1; JP2018526178A; KR20180039125A; CN108024615A; FR3040605B1; EP3346869A1

Abstract

The present invention relates to a brush for applying a product to the eyelashes and/or eyebrows, comprising: —a core, notably a twisted core, that extends along a curved longitudinal axis, and —bristles that are held by the core, the core comprising a portion (43) carrying bristles that has a proximal end (40 a) intended to be fixed to a stem and a distal end (40 b), the bristles having free ends that define an envelope surface, the envelope surface having, before the core is curved, at least one first facet (60) and at least one second facet (45) which are different from one another.

Description

The present invention relates to brushes for applying a cosmetic product to the eyelashes or eyebrows, notably a makeup or care product, for example mascara, and to packaging and application devices comprising such a brush.
A large number of applicators, in which the brush comprises a core formed by two arms of a metal wire that are twisted together and grip bristles, are known. Since the bristles used are generally the same length, once the branches are twisted, the brush has an envelope surface in the form of a cylinder of revolution. Such a cylinder of revolution form has limited effectiveness in terms of loading the eyelashes with product and separation.
Efforts have thus been made to give the envelope surface more complex shapes so as to form on the brush, after wiping, zones that are more heavily laden with product, making it possible to properly load the eyelashes, and zones that are less heavily laden or are laden little, these being usable to separate the eyelashes. Finding the shape that results in the optimum makeup result requires numerous tests, since many factors come into play.
In addition, it is economically advantageous for the brush to be able to be manufactured quickly and easily.
Numerous brushes have been proposed, with notches machined in the longitudinal direction of the core.
The patent applications EP 1 236 419, EP 1 236 420 and EP 1 236 421 disclose mascara brushes that can comprise substantially flat facets parallel to the core, having a generally oval contour. In those applications, the facets of one and the same brush are all identical.
In the applications EP 0 832 580 and EP 0 842 620, the cutouts made are symmetrical to one another.
The patent application FR 2 916 950 discloses a mascara brush having a rectilinear longitudinal axis and a polygonal cross section, along at least a part of its length.
FR 3 007 630 discloses a mascara brush having a rectilinear longitudinal axis and comprising facets that are disposed such that the brush comprises hollows alternating with reliefs around the core.
There is a need to make the application of makeup easier along the entire row of eyelashes, and notably at the corner of the eye.
There is also a need to improve brushes, notably to benefit from brushes that are capable of satisfactorily making up the eyelashes and eyebrows, by providing a sufficient load of product and satisfactory combing.
The invention aims to meet all or some of these needs and therefore the subject thereof, independently or in combination with the above, according to one of its aspects, is a brush for applying a product to the eyelashes and/or eyebrows, comprising:

- a core, notably a twisted core, that extends along a curved longitudinal axis X, and
- bristles that are held by the core, the core comprising notably a portion carrying bristles that has a proximal end intended to be fixed to a stem and a distal end, the bristles having free ends that define an envelope surface, the envelope surface having, before the core is curved, at least one first facet and at least one second facet which are different from one another.

The first facet may be disposed in the hollow of the curvature of the core. It is thus possible to form a region that can make it possible to constitute a larger reserve of product in the curvature of the core.
The second facet provides different makeup characteristics on account of its different location and its different shape.
The term “facet” denotes a cutout in the envelope surface of the brush, delimited by visible edges. A facet is preferably defined by a generatrix extending in a plane perpendicular to the longitudinal axis of the core and moving along a directrix, for example coplanar with the longitudinal axis of the core. A facet may be flat or non-flat, having for example an outwardly concave or convex curvature. Such a curvature can depend on the shape of the generatrix, be it rectilinear or curved. In a variant, the curvature of the facet can vary, the latter being for example wavy.
The expression “facets that are different from one another” should be understood as meaning that the first and second facets differ from one another by at least one of their width, length, depth, distance from the core, and inclination with respect to the core.
The second facet may be smaller than the first facet. The term “smaller” means that at least one of its width and/or its length and/or its depth is smaller than the width and/or length and/or depth of the first facet.
In a variant or additionally, the distance of the second facet from the core may be greater than the distance of the first facet from the core. Thus, the second facet may be farther away from the core than the first facet, and thus be subjected to more vigorous wiping on passing through the wiping member.
The area taken up by the second facet may differ from that taken up by the first facet by more than 10%, that is to say that |S₁−S₂|/S₁≥0.1, where S₁is the area of the first facet and S₂the area of the second facet. |S₁−S₂|/S₁≥0.2, or even |S₁−S₂|/S₁≥0.3 is possible. As seen from the longitudinal axis of the core in cross section, each first or second facet preferably extends about the axis over an angular extent of less than 120°. This ensures that each facet is located on one side of the brush.
The brush may comprise at least two second facets. The two second facets may be smaller than the first facet. The two second facets may be symmetrical to one another with respect to a plane containing the longitudinal axis of the core. The first and second facets may form a triangle when the brush is viewed in cross section.
The first and/or second facet, or both facets, may have a width which increases in the direction of the proximal end of the portion of the core carrying the bristles, along at least a portion of the length of the facet, or even along the entire length of the facet.
The first and/or second facet, or both facets, may have a width which decreases in the direction of the distal end of the portion of the core carrying the bristles, along at least a portion of the length of the facet.
The width l of a facet may decrease along its entire length measured along the longitudinal axis of the core, or else along only a portion of the latter. The width l of the facet may decrease along at least half of its length L₂, or even along at least ⅔ of its length L₂, better still along at least ¾ of its length L₂. The width l of the facet may increase and then decrease, and then increase again, or else decrease and then increase, towards the distal end of the portion of the core carrying the bristles.
The widest part of the facet may be situated closer to the proximal end than to the distal end of the portion of the core carrying the bristles, better still by less than a third, or even less than a quarter of the length L of the portion of the core carrying the bristles, with respect to the proximal end.
In one exemplary embodiment, the width l of the first facet decreases in the direction of the distal end of the portion of the core carrying the bristles.
The first and/or the second facet may extend along the entire length L of the portion of the core carrying the bristles, or else along only a part of the latter, for example along at least 50% of this length L, better still at least 60%, or even at least 70%. The facet may extend along less than 95% of the length L of the portion of the core carrying the bristles, or along less than 90%, or even along less than 80%.
The first facet may notably extend along the entire length L of the portion of the core carrying the bristles.
The second facet(s) may extend along less than 90% of the length L of the portion of the core carrying the bristles, or along less than 80%, or even along less than 70%.
The first and/or the second facet, or both facets, may notably extend as far as the proximal end of the portion of the core carrying the bristles.
The first and/or second facets, or both facets, may be delimited by an adge oriented perpendicularly to the longitudinal axis of the stem at the proximal end of the portion of the core carrying the bristles. The presence of such an edge makes it possible to improve the precision of makeup application, and in particular can make it easier to make up the eye, notably the corner of the eye, and even more particularly the inside corner of the eye.
The width of the first facet may decrease in the direction of the distal end of the portion of the core carrying the bristles.
The width of the second facet(s) may decrease in the direction of the distal end of the portion of the core carrying the bristles.
The first and/or second facets may extend parallel to the longitudinal axis X of the core. This means that the facets are each made in a plane parallel to the longitudinal axis X of the core, before the latter is curved. It is possible for the envelope surface not to have facets that are not parallel to the longitudinal axis X of the core.
In a variant or additionally, the envelope surface may define at least one facet that extends longitudinally and is inclined with respect to the longitudinal axis X of the core in the direction of the distal end. It may be the first and/or the second facet, or even a third facet.
The term “inclined” should be understood as meaning that a general direction of the facet forms an angle with the longitudinal axis of the core when the core of the brush is straightened for the purposes of observation. The generatrix defining the corresponding facet may notably move along a directrix that is not parallel to the longitudinal axis of the core, notably rectilinear and forming an angle with the latter, or curved.
At least one of the first and second facets may be inclined in the direction of the distal end of the core. This means that the inclination of the facet with respect to the longitudinal axis of the core is such that the facet becomes closer to the longitudinal axis of the core towards the distal end of the brush, when the core of the brush is straightened for the purposes of observation. All the facets of the brush may be inclined in the direction of the distal end. It is possible for the brush not to have a facet inclined in the direction of the proximal end.
In a variant or additionally, at least one of the first and second facets may be inclined in the direction of the proximal end of the core. This means that the inclination of the facet with respect to the longitudinal axis of the core is such that the facet becomes closer to the longitudinal axis of the core towards the proximal end of the brush, when the core of the brush is straightened for the purposes of observation. All the facets of the brush may be inclined in the direction of the proximal end. It is possible for the brush not to have a facet inclined in the direction of the distal end.
The facet may be inclined at an angle α of between 5 and 35 degrees, better still between 10 and 20 degrees, with respect to the longitudinal axis of the stem when the core of the brush is straightened for the purposes of observation. This means that the facet has a directrix D which is rectilinear and inclined at said angle α with respect to the longitudinal axis X of the stem, when the core of the brush is straightened for the purposes of observation. The facet is formed by the movement of a generatrix along this directrix D. The generatrix may for example extend along the rotation axis of a tool for cutting the facet, which may have a cylindrical shape and move along the directrix D during cutting.
The envelope surface may have, before the core is curved, an at least partially frustoconical or ogival overall shape. This can make it possible to have regions on the envelope surface that are situated at different distances from the core and are thus wiped differently. The most loaded regions can be used to load the eyelashes with product and the less loaded regions can be used to separate the eyelashes.
The envelope surface may comprise a distal frustoconical portion having a cross section that decreases towards the free end of the core. The angle β of the cone with respect to the longitudinal axis X may have a value of between 5 and 35 degrees, better still between 10 and 20 degrees. The distal frustoconical portion may extend along a length greater than a quarter of the length L of the portion of the core carrying the bristles, better still more than a third of the length L of the portion of the core carrying the bristles, even better still more than half the length L of the portion of the core carrying the bristles.
The envelope surface may have at least one cross section having a not entirely polygonal shape, notably having an at least partially circular shape, notably having a circular shape at the distal end. The expression “at the distal end” means that said at least one cross section is closer to the distal end than the proximal end of the portion of the core carrying the bristles, in other words less than ½ L from the distal end of the portion of the core carrying the bristles and more than ½ L from the proximal end of the portion of the core carrying the bristles, where L is the length of the portion of the core carrying the bristles measured between its proximal end and its distal end. Said at least one cross section may be less than a third, or even less than a quarter of the length L from the distal end of the portion of the core carrying the bristles. In absolute terms, the length L may be between 15 mm and 45 mm, better still between 20 mm and 40 mm, for example between 25 mm and 35 mm.
It is possible for the brush not to have a distal end in the form of a point. It may have a not entirely prismatic shape, at least at its distal end.
The circular cross section may be made at a point on the core that is situated less than ⅓ L from the distal end of the portion of the core carrying the bristles and more than ⅔ L from the proximal end of the portion of the core carrying the bristles. The circular cross section may be made at a point on the core that is situated less than ¼ L from the distal end of the portion of the core carrying the bristles and more than ¾ L from the proximal end of the portion of the core carrying the bristles.
It is possible for the brush not to have any cross section with a rectangular shape, notably at its distal end.
The core may be curved along the entire length of the portion of the core carrying the bristles. The curvature of the core may be constant or variable. The radius of curvature is for example between 20 and 60 mm. Since the brush is curved, it can be loaded more in the hollow and comb and separate better on the convex side. The distal end of the core may be situated on the longitudinal axis Y of a stem to which the brush is attached.
The brush may comprise at least one cross section with a prismatic, notably substantially triangular, overall shape, this cross section being notably situated close to the proximal end of the portion of the core carrying the bristles. The cross section with a prismatic overall shape may be situated closer to the proximal end than to the distal end of the portion of the core carrying the bristles, better still less than a third, or even less than a quarter of the length L of the portion of the core carrying the bristles, with respect to the proximal end.
The brush may comprise a proximal frustoconical portion at its proximal end, the frustoconical portion widening with increasing distance from the proximal end of the portion of the core carrying the bristles. In one embodiment, the first and/or second facet, or both facets, extend over the proximal frustoconical portion.
The brush may also comprise a cylindrical central portion situated between the distal frustoconical portion and the proximal frustoconical portion. In one embodiment, the first and/or second facet, or both facets, cover the cylindrical central portion. Each facet stops for example shortly before or at the same level as the frustoconical portion.
The brush may be chamfered at its proximal and/or distal ends. In one exemplary embodiment, the brush is chamfered at its distal and proximal ends.
Facet By virtue of the facet(s), the brush according to the invention is notably able to store more product along a part of its length so as to provide an additional load of product to the eyelashes and/or eyebrows.
The first facet may have a length L₂where L₂≥L/2, L being the length of the portion of the core carrying the bristles. Preferably, the length L₂of the first facet is such that L₂≥⅔L. In one exemplary embodiment, L₂is equal to L. This makes it possible to have a first facet which extends along a great majority of the length of the core carrying the bristles, thereby making it possible notably to obtain the desired effect on most of the eyelashes with minimum hand movements.
The second facet(s) may have a length L₃where L₃≥L/2.
The first facet may have a width l that is constant along at least a portion of its length L₂. The width l of the first facet may be between 1 mm and 4 mm, better still between 1.5 mm and 3.5 mm.
The facet(s) may have, in cross section, a flat bottom or an outwardly convex bottom.
The envelope surface, apart from the facets, may be cylindrical. The envelope surface, apart from the facets, may be a surface of revolution.
The envelope surface may be symmetrical with respect to the longitudinal axis X of the core. In a variant, the envelope surface does not exhibit axial symmetry.
The core of the brush is fixed preferably by its proximal end to a stem. The stem may be fixed at its other end to a closure cap of a container.
Preferably, the core is a twisted core. The expression “twisted core” should be understood as meaning a core formed by twisting together two arms of a metal wire in a conventional manner.
Device
A further subject of the invention is a packaging and application device comprising:

- a container containing a product to be applied,
- a brush according to the invention.

The container may be provided with a wiping member for removing the excess product present on the stem and on the brush. This wiping member comprises for example a lip made of an elastomeric material, defining a wiping orifice which is preferably of circular section, the diameter of which corresponds substantially to that of the stem.
Manufacturing Method
A further subject of the invention is a method for manufacturing a brush according to the invention, comprising the steps of:

- producing a brush blank having a rectilinear core, notably having a twisted core, notably having an envelope surface that has, before the core is curved, a non-cylindrical shape, preferably a rotationally symmetrical shape, notably an at least partially frustoconical or ogival overall shape,
- cutting the bristles so as to obtain facets according to the invention, and
- curving the core.

Preferably, the core is curved at the first facet such that the first facet is disposed in the hollow of the curvature of the core.
The core is curved for example in a median plane of the first facet.
The facet(s) can be formed by moving a cutting tool both along an axis parallel to the longitudinal axis of the core and along an axis perpendicular to the longitudinal axis of the core.
In a variant or additionally, the facet(s) can be formed by moving a cutting tool about an axis perpendicular to the longitudinal axis of the core, notably an axis parallel to the facet.
The cutting tool preferably has a rotation axis parallel or perpendicular to the facet.

DETAILED DESCRIPTION

The invention may be better understood from reading the following detailed description of non-limiting exemplary embodiments thereof and from examining the appended drawing, in which:

FIG. 1 shows an example of a packaging and application device according to the invention, in schematic and partial longitudinal section,

FIG. 2 is a side view of an example of a brush according to the invention,

FIG. 3 is a view of the brush from FIG. 2 before the core is curved,

FIG. 4 is a view along the arrow IV,

FIGS. 5 and 6 are views similar to FIGS. 3 and 4 of a blank of the brush from FIG. 2,

FIG. 7 is a view similar to FIG. 2 of a variant brush according to the invention,

FIGS. 8 and 9 are views along the arrows VIII and IX, respectively, before the core is curved,

FIG. 10 is a view along the arrow X, and

FIGS. 11 and 12 are views similar to FIGS. 5 and 6 of a blank of the brush from FIG. 7.

In the rest of the description, identical elements or elements having identical functions bear the same reference signs. Their description is not repeated for each of the figures, only the main differences between the embodiments being mentioned.
The packaging and application device 1 shown in FIG. 1 comprises a container 2 containing a product P to be applied to the eyelashes or eyebrows and an applicator 3 which may be fixed removably to the container 2 in the example in question. The product P comprises, for example, one or more pigments, in particular an iron oxide. It is for example a mascara.
The applicator 3 comprises a stem 5 of longitudinal axis Y, which stem 5 is provided at a distal end 5 a with a brush 10 according to the invention and is provided at the other end with a gripping member 11, which likewise forms a cap for closing the container 2 in a sealed manner. As can be seen notably in FIG. 1, the latter comprises a body 13 which is provided at the top with a threaded neck 14 onto which the gripping member 11 can be screwed in order to close the container 2 in a sealed manner. In a variant, the applicator can be fixed to the container in some other way.
The neck 14 may accommodate, as illustrated, a wiping member 20 which is for example inserted into the neck 14. This wiping member 20 comprises a lip 26 that defines a wiping orifice having a diameter adapted to that of the stem 5.
The brush 10 can be fixed, in a conventional manner, in a seat provided at the distal end 5 a of the stem 5, which is advantageously made of a thermoplastic material. The brush 10 comprises a twisted metal core 40 comprising a portion 43 carrying bristles 41. The core is fixed at a proximal end 40 a in the corresponding housing of the stem 5 by a portion that does not have bristles, it being possible for said portion to have a length of around 8 mm. The portion 43 of the core carrying the bristles has a free end 40 b.
The free ends of the bristles 41 define, as illustrated in FIG. 2, an envelope surface S of the brush 10. The bristles 41 extend along a length L of the core of preferably between 25 mm and 35 mm, for example equal to 30 mm.
The core 40 is formed conventionally by two arms of a metal wire folded in a U-shape, the bristles 41 being held between the turns of the core 40. The diameter of the metal wire is for example between 0.1 and 1 mm. The diameter of the bristles is for example between 0.06 and 0.35 mm.
The core 40 of the brush 10 according to the invention is curved, extending along a curved longitudinal axis X. It is curved in a plane P which, in the example described, is a plane that contains the longitudinal axis X and is perpendicular to a first facet 60 which will be described below. This plane P is a plane of symmetry for the brush. The brush is curved along the entire length of the portion 43 and the distal end 40 b of the core is situated on the longitudinal axis X and on the longitudinal axis Y of the stem.
Furthermore, as illustrated in FIGS. 2 to 6, the envelope surface S comprises a first facet 60 which extends, before the core is curved, and as illustrated in FIGS. 3 and 4, parallel to the longitudinal axis X of the core and along a length L₂equal to the length L of the portion of the core carrying the bristles. After the core has been curved, the first facet 60 is disposed in the hollow of the curvature of the core, as illustrated in FIG. 2.
The core is curved in a plane P which is the plane of FIG. 2, said plane P being perpendicular to a plane Q of the facet 60. The plane P is a median plane of the first facet.
The first facet 60 has a width l which decreases in the direction of the distal end 40 b of the portion 43 of the core carrying the bristles.
The envelope surface S also comprises two second facets 45 which are symmetrical to one another with respect to a plane P containing the longitudinal axis of the core and form a triangle with the first facet 60 when the brush is viewed in cross section.
In the example described, the three facets 45 and 60 extend longitudinally and are flat, each extending in a plane parallel to the longitudinal axis X of the core.
These second facets 45 are different from the first facet 60. They differ therefrom by way of their length L₃which corresponds to around 60% of the length L of the portion 43 of the core carrying the bristles. Their width e is also less than the width l of the first facet 60.
Moreover, the depth of the two second facets 45 is less than the depth of the first facet 60. In other words, the distance d₂of the second facet 45 from the core is greater than the distance d₁of the first facet 60 from the core, as can be seen in FIG. 4. Thus, the second facet 45 is farther away from the core than the first facet 60.
The facets 45 have a width l which decreases in the direction of the distal end 40 b of the portion 43 of the core carrying the bristles.
The first facet 60 and the two second facets 45 are delimited in part by an edge 50 that is perpendicular to the longitudinal axis X of the core and is situated at the proximal end 40 b. In the example described, the facets 45 and 60 do not meet at their proximal end. The cross section of the brush has a substantially triangular shape at the proximal end 40 a of the brush.
As seen from the longitudinal axis of the core in cross section, each first facet 60 or second facet 45 respectively extends about the axis X over an angular extent γ₁and γ₂of less than 120°.
The envelope surface S has at least one cross section with a circular shape. In the example described, this circular cross section is situated close to the distal end 40 b.
The envelope surface S has, before the core is curved, a partially frustoconical overall shape, as can be seen in FIGS. 5 and 6, in which the blank of the brush from FIG. 2 has been illustrated. More specifically, the envelope surface comprises a distal frustoconical portion 51 having a cross section that decreases towards the free end of the core, a proximal frustoconical portion 53 having a cross section that decreases towards the proximal end of the core, and a cylindrical central portion 52 situated between the distal frustoconical portion 51 and proximal frustoconical portion 53.
The angle β of the cone of the distal frustoconical portion 51 with respect to the longitudinal axis X may have a value of around 15°.
The maximum radius R of the envelope surface S, corresponding to the radius of the smallest cylinder of revolution in which the brush is inscribed, is between 3 mm and 6 mm, for example 4.5 mm.
In the variant embodiment illustrated in FIGS. 7 to 12, the brush 10 has an overall shape, apart from the facets 45 and 60, with a convex profile. It can be seen that the blank of this brush, before the formation of the facets and before the core is curved, which is illustrated in FIGS. 11 and 12, has a partially ogival shape.
This variant embodiment illustrated in FIGS. 7 to 12 also differs from the above by the presence of two third facets 65 situated in continuation of the facets 45, the length of which is L−L₃and the width of which increases towards the distal end 40 b of the brush.
Moreover, the facet 60 is situated in this example at 450 to the facets 45 and 65 with respect to the longitudinal axis X.
Generally, the envelope surface can comprise a different number of facets and it is possible for the latter not to be identical to one another and/or distributed evenly around the core 40.
The ends 40 a and 40 b of the envelope surface S can be chamfered. This can make it easier for the brush 3 to pass through the wiping member 20. The chamfer at the distal end and the chamfer at the proximal end can be different. The chamfer at the distal end can, notably, be less inclined than that at the proximal end. In a variant, it is possible for the brush not to have such chamfers at the end.
The invention is not limited to the exemplary embodiments which have just been described, the characteristics of which may be combined with one another as parts of variants which are not illustrated.

Claims

1: Brush for applying a product to the eyelashes and/or eyebrows, comprising:

a core that extends along a curved longitudinal axis, and

bristles that are held by the core, the core comprising a portion carrying bristles that has a proximal end intended to be fixed to a stem and a distal end, the bristles having free ends that define an envelope surface,

the envelope surface having, before the core is curved, at least one first facet and at least one second facet which are different from one another.

2: Brush according to claim 1, wherein the first facet is disposed in the hollow of the curvature of the core.

3: Brush according to claim 1, wherein the second facet is smaller than the first facet.

4: Brush according to claim 1, which comprises at least two second facets.

5: Brush according to claim 4, wherein the two facets are symmetrical to one another with respect to a plane containing the longitudinal axis of the core.

6: Brush according to claim 1, wherein the first and second facets form a triangle when the brush is viewed in cross section.

7: Brush according to claim 6, wherein the first and/or second facets, or both facets, are delimited by an edge oriented perpendicularly to the longitudinal axis of the stem at the proximal end of the portion of the core carrying the bristles.

8: Brush according to claim 1, wherein the width of the first facet decreases in the direction of the distal end of the portion of the core carrying the bristles.

9: Brush according to claim 1, wherein the envelope surface has, before the core is curved, an at least partially frustoconical or ogival overall shape.

10: Brush according to claim 1, wherein the envelope surface comprises a distal frustoconical portion having a cross section that decreases towards the free end of the core.

11: Brush according to claim 1, wherein the envelope surface comprises a cylindrical central portion situated between a distal frustoconical portion and a proximal frustoconical portion.

12: Brush according to claim 1, wherein the envelope surface has at least one cross section of circular shape situated at the distal end.

13: Brush according to claim 12, wherein the distal end of the core is situated on the longitudinal axis of a stem to which it is attached.

14: Brush according to claim 1, wherein the core is fixed by its proximal end to a stem.

15: Packaging and application device comprising a container containing a product to be applied and a brush according to claim 1.