WO2012140572A1

WO2012140572A1 - A mascara brush

Info

Publication number: WO2012140572A1
Application number: PCT/IB2012/051755
Authority: WO
Inventors: Jean-Louis Gueret
Original assignee: L'oreal
Priority date: 2011-04-12
Filing date: 2012-04-11
Publication date: 2012-10-18
Also published as: EP2696722B1; FR2973991A1; JP6250532B2; ES2683172T3; CN103458729A; FR2973991B1; EP2696722A1; CN103458729B; JP2014510604A

Abstract

The present invention relates to a packaging and applicator device (1) for applying a composition (P) to the eyelashes or the eyebrows, said device comprising: - a container(2) containing the composition; and - a brush (5) comprising: - a core that extends along a rectilinear longitudinal axis; and ·bristles that are connected to the core, the free ends of the bristles defining an envelope surface, the brush having a varying portion which cross-section varies along the longitudinal axis and passes through at least one maximum or minimum of section at a non-zero distance from its axial ends; the envelope surface not having a plane surface along the varying portion, and defining at least one facet(20) that is not plane and that is not parallel to the longitudinal axis of the core, the facet being defined by at least one edge that is never rectilinear and that is contained in a plane that passes through the core, the edge presenting a distance to the longitudinal axis of the core that passes through a maximum wherever the cross-section of the varying portion also passes through said maximum of section, and through a minimum wherever the cross-section of the varying portion also passes through said minimum of section.

Description

A MASCARA BRUSH

The present invention relates to applicators for applying a cosmetic composition to the eyelashes or the eyebrows, said applicators also being known as mascara brushes.

A mascara brush should enable the eyelashes to be loaded with composition, without however clumping the eyelashes together. The brush should thus also be capable of separating the eyelashes.

Brushes have been made available with a wide variety of shapes, with the purpose of obtaining both loading and separating properties that are satisfactory.

In particular, brushes are known having facets that are machined on a brush blank as described in EP

application n° 1369056 Al . The presence of facets makes it possible, after passing through a wiper member, to obtain a distribution of composition on the brush that is not uniform, with some zones carrying more composition and thus being better adapted to loading the eyelashes, and other zones carrying less composition and thus being better adapted to separating the eyelashes.

Within a cross-section, certain known brushes present differences of length between the bristles that are relatively substantial. In use, this leads to an accumulation of composition that is excessive, and also to flattening of the brush and/or of the wiper member.

There exists a need to improve mascara brushes still further, and in particular to reach a satisfactory compromise between the separating ability of the brush and its loading ability. In addition, the brush should be able to be made easily, and to be used by the user without any special precautions. Preferably, the above- mentioned flattening problem is reduced, or even

eliminated .

Exemplary embodiments of the invention provide packaging and applicator device for applying a composition to the eyelashes or the eyebrows, said device comprising :

^• a container containing the composition; and

^• a brush comprising:

· a rectilinear core that extends along a longitudinal axis; and

^• bristles that are connected to the core, the free ends of the bristles defining an envelope surface, the brush having a varying portion of cross-section that varies along the longitudinal axis and that passes through at least one extremum at a non-zero distance from its axial ends;

the envelope surface not having a plane surface along the varying portion, and defining at least one facet that is not plane and that is not parallel to the longitudinal axis of the core, the facet being defined by at least one edge that is never rectilinear and that is contained in a plane that passes through the core, the edge presenting a distance to the longitudinal axis of the core that passes through a maximum wherever the cross-section of the varying portion also passes through a maximum, and through a minimum wherever the cross- section of the varying portion also passes through a minimum.

The invention makes it possible to satisfy the above-mentioned need. The shape of the brush enables wiping to be progressive.

In exemplary embodiments of the invention, the brush defines at least three facets around the longitudinal axis of the core, at least two of which are not plane, are of the same shape, and are not parallel to the longitudinal axis.

At least one longitudinal strip of the envelope surface may extend between two adjacent facets when said facets are at a distance from each other, or one

longitudinal edge may be formed at the junction of two facets when said facets are contiguous. The strip or the edge presents a distance to the axis of the core that varies along the axis of the core. When it exists, the longitudinal strip presents a shape that is not plane between its axial ends.

The term "distance to the core" of the envelope surface at a point along the core should be understood to mean the shortest distance to the core within a cross- section of the envelope surface of the brush that passes through said point. Said shortest distance is designated by the magnitude d_mi_n. In addition, d_max designates the greatest distance from the envelope surface to the longitudinal axis of the core, within the same cross- section .

Each facet has a distance to the core that varies along the varying portion.

The variation includes an extremum.

In a plane constituting a mid-plane for a facet and containing the longitudinal axis of the core, a tangent to the facet has a slope that varies along the facet. Preferably, over at least a portion of the length of the facet, the slope formed by the tangent relative to the longitudinal axis of the core varies in monotonic manner. For example, the slope decreases continuously, passes through zero, and then increases continuously. By way of example, the slope is zero at the point at which the cross-section of the envelope surface is at its maximum or its minimum, e.g. substantially mid-way along the bristled portion of the brush.

The brush need not have any facet of a shape that is cylindrical around an axis that is at a constant angle relative to the longitudinal axis of the core. The brush need not have any rectilinear edge parallel to the longitudinal axis of the core.

In a plane constituting a mid-plane for a

longitudinal strip and containing the axis of the core, a tangent to the longitudinal strip that extends between two adjacent facets may have a slope that likewise varies along the longitudinal strip, e.g. increasing then decreasing, or vice versa, from one end of the

longitudinal strip to the other.

Preferably, in the cross-section of the brush where the distance d_max is at its maximum for the entire brush, I d_max-d_min I /d_min ≤ 3. Thus, the brush presents zones having different properties without the relative differences in the lengths of the bristles within a single cross-section being very substantial; it is thus easier to avoid having zones with bristles that are too short and thus load too much composition on the eyelashes, which could make the operation of applying makeup more difficult and/or generate a problem of the brush and/or the wiper member being flattened.

Preferably, all of the facets are of the same shape, and the portion of the envelope surface that corresponds to a facet becomes superposed on the portion of the envelope surface that corresponds to another facet of identical shape, on turning the brush about the

longitudinal axis.

The distance d_mi_n may be greater than or equal to 3.5 mm at the point at which the cross-section of the brush is at its greatest, e.g. approximately mid-way along the bristled portion of the brush for a brush that is generally egg shaped. The distance d_max may be greater than or equal to 5 mm, or greater than or equal to 14 mm, at the point at which the cross-section of the brush is at its greatest.

The envelope surface may present axial symmetry about the longitudinal axis of the core.

At least one facet may present a profile that is concave or convex when the brush is observed in at least one direction of observation that is perpendicular to the longitudinal axis of the core. All of the facets are preferably non-plane. Also preferably, when the brush is observed perpendicularly to its longitudinal axis, the facets are either convex or concave, without any points of inflection and without any undulating shapes.

In cross-section, the facets may present a profile that is rectilinear, concave, or convex.

Two adjacent facets may be contiguous in a given cross-section. In a variant, two adjacent facets may be at a non zero distance from each other in a given cross- section, thus being separated by a longitudinal strip as defined above. Where appropriate, the longitudinal strip may be of zero width over at least a fraction of the length of the brush, the facets thus locally touching.

The core may be twisted, in particular it may have a right-hand twist or a left-hand twist.

The bristles may be of diameter lying in the range 6/100 mm to 35/100 mm. The strands of the core may be of diameter lying in the range 0.35 mm to 1.5 mm.

The cross-section of the envelope surface may pass through an extremum, preferably a maximum, between one third and two thirds of the way along the portion of the core carrying bristles.

The varying portion may extend over the entire length of the portion of the core that carries the bristles. In a variant, the varying portion extends over a fraction only of the portion of the core that carries the bristles. The brush may include distal and proximal envelope-surface portions that are prismatic in shape, the distal portion being longer than the proximal

portion, for example. The varying portion may be

situated between the proximal and distal portions.

The facets may extend axially as far as the distal and/or proximal end(s) of said portion carrying the bristles. In a variant, the brush presents an

intermediate portion that carries said facets, and proximal and distal portions that have their own facets, e.g. that are plane and oriented obliquely relative to the longitudinal axis of the core, and that are preferably situated to extend the facets of the

intermediate portion.

Advantageously, the container is fitted with a wiper member .

The invention also provides a method of applying makeup to the eyelashes or the eyebrows, in which method the composition is applied to the eyelashes or to the eyebrows by means of a device of the invention.

When said brush is a twisted-core brush, in order to manufacture said brush, it is possible to start from a blank of shape that is circularly cylindrical, which blank is then machined so as to impart thereto a shape that is circularly symmetrical, with a longitudinal profile that is not rectilinear. At this stage, the envelope surface of the brush is thus in the shape of an American football, an hourglass, a fish, or a peanut, for example. Then, the facets are trimmed. It is also possible to pass directly from a circularly-cylindrical blank to the final shape by machining the brush.

The present invention can be better understood on reading the following detailed description of non- limiting embodiments thereof, and on examining the accompanying drawings, in which:

^• Figure 1 is a diagrammatic longitudinal section view of an example of a packaging and applicator device made in accordance with the invention;

^• Figure 2 shows the brush of the Figure 1

applicator in isolation;

^• Figure 3 is an end view as seen looking along direction III of Figure 2;

^• Figure 4 is a cross-section of the brush in a plane in which the transverse dimension of the envelope surface is at its maximum;

^• Figures 5, 7, 9, 11, 13, and 17 are views similar to Figure 2 of variant embodiments of the brush; ^• Figures 6, 8, 10, 12, and 14 are end views

respectively as seen looking along directions VI, VIII, X, XII, and XIV of Figures 5, 7, 9, 11, and 13;

^• Figures 15A to 15C are cross-sections, each showing the envelope surface of the blank and of the brush obtained after machining, for three variant

embodiments ;

^• Figures 16A to 16C are longitudinal sections of the envelope surface of variant embodiments of the brush;

· Figure 18 shows the possibility of the core forming an angle with the longitudinal axis of the stem at the outlet therefrom; and

^• Figure 19 shows a variant embodiment of the container .

The packaging and applicator device 1 shown in

Figure 1 comprises: a container 2 containing the

composition P for application; and an applicator 3 comprising a stem 4 of longitudinal axis X, provided at one end with a brush 5 and at the other end with a handle 6 that also constitutes a closure cap for closing the container 2.

The composition P is for application to the

eyelashes and/or the eyebrows. It may include iron oxide, amongst others pigments, and an aqueous or organic solvent, depending on the formulation.

The container 2 comprises a body 2b that is provided with a neck 7 in which there is engaged a wiper member 8 presenting a lip 9 that is adapted to wipe the stem 4 while it is being removed from the container. By way of example, the lip 9 defines an orifice of section that is circular, and of diameter that is slightly greater than the diameter of the stem 4. As shown, the stem may be provided at its distal end with an intermediate element 10 that is elastically deformable, and in which the brush 5 is fastened, the intermediate element 10 itself being engaged in a housing of a rigid portion of the stem. By way of example, the intermediate element 10 may be as described in US application No. 2008/0107470.

The wiper member 8 may be of any kind, and, in particular, it may be conventional or as described in US applications Nos. 2009/0028627 or 2009/0052969.

Figure 2 is a diagram showing the brush 5 in

isolation .

The brush 5 includes a core 11 that extends along a rectilinear longitudinal axis Y that coincides with the longitudinal axis of the stem 4.

The core 11 is preferably constituted by two metal strands that are twisted together so as to trap bristles having free ends that define an envelope surface E.

By way of example, the core 11 is formed by folding a wire into a U-shape, then twisting said wire about its own axis after the bristles have been inserted between the strands. The core 11 presents a proximal portion 11a that does not have bristles, and a bristled portion lib of rectilinear longitudinal axis that carries the

bristles. The ends of the bristles 32 of the brush 5, taken between the turns of the core 11, define the envelope surface E, as shown in Figure 4. The portion 11a is received in a housing of the stem 4, possibly provided with an intermediate element 10 as shown.

The bristled portion lib is of total length L_max, measured along the longitudinal axis of the core 11.

In the embodiment in Figure 2, the varying portion of the brush extends over the entire bristled portion lib of the core.

The envelope surface E presents a cross-section that varies along the bristled portion, and that, at at least one point along its length, passes through at least one extremum that is situated at a non-zero distance from the distal and proximal ends 13a and 13b of the bristled portion.

At the point at which the envelope surface E is at its maximum, as shown in Figure 4, a greatest transverse dimension D of the envelope surface E lies in the range 10 mm to 35 mm, or in the range 10 mm to 28 mm, for example .

In the embodiment in Figure 2, the cross-section of the envelope surface E of the brush passes through a maximum in a middle region, the envelope surface E having a general bulbous shape, like an American football with facets .

The envelope surface E defines a plurality of facets 20 of identical shape, and which, by way of example, are separated by longitudinal strips 21, each extending between two adjacent facets 20, as shown.

As shown in Figure 2, the facets 20 may extend axially as far as the distal and proximal ends 13a and 13b of the bristled portion of the brush 5.

The facets 20 may be formed by machining a brush blank having an envelope surface that is a surface of revolution. Machining may be performed by a machine that is numerically controlled. By way of example, machining is performed in such a manner as to give the facets a profile that is generally outwardly convex when the brush is observed in a direction that is perpendicular to its longitudinal axis Y, as shown in Figure 2, and that is outwardly concave when the brush is observed along its longitudinal axis Y, as shown in Figure 3. Machining may also be performed in two stages, namely giving the blank an egg shape starting from a shape this is circularly cylindrical, and then trimming the egg-shaped blank to produce the facets, the facets trimmed in this way not being plane.

The width ( 2 of the facets 20, measured between the edges 24 via which said facets join the longitudinal strips 21, may vary along the longitudinal axis Y of the brush 5, e.g. passing through a maximum at the point at which the envelope surface E presents a greatest cross- section. By way of example, and as shown, the edges 24 that border a single facet 20 are two curved lines that are concave towards each other, when the facet is

observed from above. The distance from the edges 24 to the core vary along the axis of the core.

The width (₁ of the longitudinal strips 21 varies between the ends 13a and 13b of the bristled portion. By way of example, the width (₁ is at its maximum at the point at which the cross-section of the envelope surface E is at its maximum.

In Figure 4, it can be seen that the distance from the envelope surface E to the axis Y varies within a cross-section, between a maximum value d_max and a minimum value d_mi_n . In the embodiment in Figures 2 to 4, d_max is reached at the longitudinal strips 21, and d_mi_n is reached at the middle of the facets 20.

Each edge 24 extends in a single plane that contains the longitudinal axis of the core. Such a plane K is shown in Figure 4.

At the point at which the cross-section of the envelope surface E is at its maximum, the ratio

I d_max-d_min I /d_min lies in the range 0.1 to 3, or in the range 0.1 to 5, for example. By way of example, d_max equals 8 and d_mi_n equals 3.5 for a brush in which the envelope surface E passes through a cross-section maximum mid-way along the bristled portion.

In the embodiment in Figures 2 to 4, the brush presents four facets 20 that are separated by the same number of longitudinal strips 21.

In these figures, at the point at which the cross- section of the brush is at its maximum, i.e. mid-way along the varying portion, it can be seen that the distance from the edges 24 to the longitudinal axis Y of the core is also at its maximum.

It would not be beyond the ambit of the present invention for the number of facets to be different, while nevertheless being greater than or equal to three, or even greater than or equal to two. In the embodiment in Figures 5 and 6, the brush thus includes three facets 20 that are separated by three longitudinal strips 21.

In the embodiment in Figures 7 and 8, the number of facets 20 is six, and said facets are contiguous, being connected together via edges 24. However, by way of example, and as shown, the facets 20 have a profile that is outwardly concave in cross-section.

For example, between the ends of the bristled portion of the brush and the point at which the cross- section is at its greatest, the greatest transverse dimension of the envelope surface E varies by a factor that is not less than 2, as can be seen in Figures 3, 6, or 8, for example.

As can be seen in Figures 9, 11, and 13, the

bristled portion may include an intermediate portion 5a that corresponds to the varying portion. Said portion may present a plurality of facets 20, and the envelope surface E of the intermediate portion 5a may define an extremum of the cross-section of the envelope surface E of the bristled portion of the brush, specifically a minimum in the embodiment in these figures.

The facets 20 are connected to distal and proximal portions 5b and 5c that may present prismatic shapes with respective facets 20b and 20c, as shown. Each of the facets 20b and 20c is situated in the prolongation of a facet 20 of the intermediate portion 5a and may be plane, the facets 20 not being plane.

In the embodiment in Figure 9, the cross-section of the envelope surface E of the brush 5 increases over the distal portion 5b, towards the stem 4, while conserving the same shape in cross-section, namely square in the embodiment shown, then decreases, passing through a minimum substantially mid-way along the intermediate portion 5a, and increases once again until it reaches the proximal portion 5c, at which point said cross-section decreases towards the proximal end 13b of the bristled portion. The facets 20b and 20 may be connected together forming edges 27 that are arranged as the sides of a polygon, in particular a square, in a common plane that is perpendicular to the longitudinal axis of the core. The facets 20 and 20c may be connected together via edges 28, also arranged as the sides of a polygon, in

particular a square.

In the embodiment in Figures 9 and 10, the facets 20 are contiguous, being connected together via edges 24 that present a distance to the axis Y that varies along the axis Y.

The facets 20 may have a profile that is rectilinear when observed along the axis Y, as shown in Figures 10, 12, or 14.

In Figures 9, 11, and 13, at the point at which the cross-section of the brush is at its minimum, mid-way along the varying portion, it can be seen that the distance from the edges 24 to the longitudinal axis Y also passes through a local minimum.

Figure 15A shows the possibility of the facets 20 presenting, in cross-section, a profile that is outwardly convex, e.g. with a radius of curvature that is greater than the radius of curvature of the envelope surface Ei of the circularly-cylindrical blank from which the brush is made.

Figure 15B shows the possibility of the facets 20 presenting, in cross-section, a profile that is

rectilinear, the greatest width ( 2 of each of the facets 20 being, for example, such that the edges 24 formed at the junction of the facets 20, form part of the envelope surface Ei of the blank that served to make the brush, at at least one point along the length of the brush.

Figure 15C shows the possibility of the brush 5 presenting facets 20 that are not all of identical shape, e.g. with alternating facets 20 having, in cross-section, a profile that is rectilinear and a profile that is concave. Figure 15C also shows the possibility of the brush 5 presenting at least two facets having an

identical shape, said at least two facets being situated diametrally opposite each other.

Figures 16A to 16C show various shapes for the envelope surface E, in longitudinal section along the axis Y, each of the brushes 5 being capable of receiving any number of facets, greater than or equal to three, e.g. with facets having the same shapes as shown in the above-described embodiments. The facets may optionally be separated by longitudinal strips 11.

In the embodiment in Figure 16A, the envelope surface E presents the shape of a drop of water, in the embodiment in Figure 16B, the envelope surface E presents the shape of a fish, and in the embodiment in Figure 16C, the envelope surface E presents the shape of a ball.

Where appropriate, the core 11 may be curved at the outlet from the stem 4 so that the rectilinear

longitudinal axis of the portion of the core carrying bristles forms a non-zero angle a with the longitudinal axis X of the stem 4, as shown in Figure 18. By way of example, the angle a lies in the range 1° to 20°.

The container 2 can be of various shapes and can be made in such a manner that the brush 5 is situated in the proximity of the inside surface 2a of the container while the brush 5 is being removed from or inserted into the container .

Figure 19 shows the possibility of making the container 2 with a double sheath, the inner sheath defining the inside surface 2a of the container that is in contact with the composition. The inside surface 2a may be circularly cylindrical over a major fraction of the stroke along which the brush moves inside the

container. The brush and the container may be made in accordance with the teaching of US application

No. 2011/0030718 Al .

Figure 17 shows the possibility of subjecting the bristles that define the various facets of the envelope surface to special treatment, while the ends of the bristles that are not situated in the facets possibly not being subjected to treatment, or being subjected to different treatment.

The brush 5 may thus present, firstly, facets 20 having bristles with ends that present a first

appearance, and, secondly, longitudinal strips 21 between the facets 20 and having bristles with ends that present a different appearance.

By way of example, the ends of the bristles that form part of the longitudinal strips 21 may be subjected to heat treatment, so as to form beads at the ends of the bristles, and the ends of the bristles that define the facets 20 may be subjected to no special treatment, or vice versa.

The invention is not limited to the embodiments shown. In particular, features of the various

embodiments shown could be combined with one another to form variants that are not shown.

The bristles could include a material that has bacteriostatic properties and/or that favors sliding and/or that is magnetic.

A mixture of bristles could be used in any of the embodiments made in accordance with the invention. By way of example, the bristles could be made out of various materials. The bristles could be subjected to a

treatment as described in US patent No. 7 125 188.

Although the embodiments shown relate to a twisted- core brush, the invention also applies to an injection- molded brush in which the bristles are molded with the core, out of the same material or out of a different material .

The expression "comprising a" should be understood as being synonymous with "comprising at least one" unless specified to the contrary.

Claims

A packaging and applicator device (1) for applying a composition (P) to the eyelashes or the eyebrows, said device comprising:

^• a container (2) containing the composition; and

^• a brush (5) comprising:

^• a core (11) that extends along a rectilinear longitudinal axis; and

^• bristles (32) that are connected to the core (11), the free ends of the bristles defining an envelope surface (E) , the brush having a varying portion which cross-section varies along the

longitudinal axis and passes through at least one maximum or minimum of section at a non-zero distance from its axial ends;

the envelope surface (E) not having a plane surface along the varying portion, and defining at least one facet (20) that is not plane and that is not parallel to the longitudinal axis (Y) of the core, the facet being defined by at least one edge (24) that is never rectilinear and that is contained in a plane (K) that passes through the core, the edge (24) presenting a distance to the longitudinal axis of the core that passes through a maximum wherever the cross-section of the varying portion also passes through said maximum of section, and through a minimum wherever the cross- section of the varying portion also passes through said minimum of section. A device according to claim 1, with | d_max-d_mi_n I /d_mi_n ≤ 3, where d_max designates the greatest distance from the envelope surface (E) to the longitudinal axis (Y) , and where d_mi_n designates the shortest distance from the envelope surface (E) to the longitudinal axis (Y) , in the cross-section where the distance d_max is at its maximum for the entire brush. A device according to claim 2, the distance d_mi_n being greater than or equal to 3.5 mm at the point at which the cross-section of the envelope surface of the brush is at its greatest.

A device according to claim 2, the distance d_max being greater than or equal to 5 mm at the point at which the cross-section of the envelope surface (E) of the brush is at its greatest.

A device according to any preceding claim, the envelope surface (E) presenting axial symmetry about the longitudinal axis of the core and/or all the facets (20) being of a same shape.

A device according to any preceding claim, at least one facet (20) presenting a profile that is concave when the brush is observed in at least one direction of observation that is perpendicular to the

longitudinal axis (Y) of the core.

A device according to any preceding claim, in cross- section, the facets (20) presenting a profile that is rectilinear, concave, or convex.

A device according to any preceding claim, two adjacent facets (20) being contiguous in a given cross-section .

A device according to any one of claims 1 to 7, two adjacent facets (20) being at a non zero distance from each other in a given cross-section.

10. A device according to any preceding claim, the core (11) being twisted. A device according to any preceding claim, the cross- section of the envelope surface (E) passing through an extremum, preferably a maximum, between one third and two thirds of the way along the portion (lib) of the core carrying bristles.

12. A device according to any preceding claim, the

including distal (5b) and proximal (5c) envelop surface portions that are prismatic in shape.

13. A device according to any preceding claim, the facets (20) extending axially as far as the distal and/or proximal ends of said portion (lib) carrying the bristles .

14. A mascara brush (5) comprising:

^• a core (11) that extends along a longitudinal axis (Y) ; and

^• bristles (32) that are held by a portion (lib) of the core;

the free ends of the bristles defining an envelope surface (E) , the brush having, over at least half of the total length (L_max) of said portion (lib), a cross- section that is not constant and that passes through at least one extremum at a non-zero distance from the axial ends (13a, 13b) of said portion (lib), and defining, around the longitudinal axis of the core, at least three facets (20), at least two of which are not plane, are of the same shape, and are not parallel to the longitudinal axis (Y) of the core when said longitudinal axis is, if necessary, made rectilinear for observation purposes, at least one non-plane longitudinal strip (21) of the envelope surface (E) extending between two adjacent facets (20) when said facets are at a distance from each other, or a

longitudinal edge (24) being formed at the junction of two facets when said facets are contiguous, the strip (21) or edge (24) presenting a distance (d_max) to axis (Y) of the core (11) that varies along the (Y) of the core.