Abstract
The present invention relates to a brush (10) for applying a product (P) to the eyelashes and/or eyebrows, comprising: a core (40) that extends along a longitudinal axis X, and bristles (41) that extend from the core (40) along a portion of length L.sub.2, the ends of the bristles (41) defining an envelope surface, the envelope surface having at least one longitudinally extending cutout, the cutout having: a length L.sub.2 where L.sub.2≥L.sub.1/2, a width w, measured at the bottom of the cutout, that is constant along at least a portion of its length L.sub.2, and a distance d from the longitudinal axis X that varies along its length L.sub.2.
Claims
1. A brush for applying a product to the eyelashes and/or eyebrows, comprising: a twisted core having a longitudinal axis, the twisted core extends along a longitudinal axis of the brush, and bristles that extend from the core along a portion of length L.sub.1, the ends of the bristles defining an envelope surface S, the envelope surface S having at least one longitudinally extending cutout, the cutout being bordered and defined by flanks and having: a length L.sub.2 where L.sub.2≥L.sub.1/2, a width w, measured at a bottom of the cutout, that is constant along at least a portion with a length L.sub.3 along the longitudinal axis greater than or equal to 50% of its length L.sub.2, and a distance d from the longitudinal axis that varies along its length L.sub.2, the bottom of the cutout of the envelope surface having, in a longitudinal section comprising the longitudinal axis of the core, a profile that is concave towards an outside of the brush.
2. The brush according to claim 1, wherein the bottom of the cutout is, in a section perpendicular to the longitudinal axis of the core, flat or convex towards the outside of the brush.
3. The brush according to claim 1, wherein the flanks that define the cutout diverge relative to one another in a direction extending towards the outside of the brush.
4. The brush according to claim 1, wherein the distance d from the longitudinal axis varies continuously along its length L.sub.2.
5. The brush according to claim 1, wherein the distance d of the cutout from the longitudinal axis forms a curve that does not have any angular points.
6. The brush according to claim 1, wherein the length L.sub.2 of the cutout is such that L.sub.2≥2/3L.sub.1.
7. The brush according to claim 1, wherein the ratio w/W is between 0.9 and 0.4, W being the width of the cutout measured at a top surface of the cutout immediately adjacent to a top surface of the flanks.
8. The brush according to claim 1, wherein the envelope surface S has a plurality of cutouts.
9. The brush according to claim 8, wherein the cutouts are distributed evenly around the core.
10. The brush according to claim 9, wherein the ratio w/D is between 0.4 and 0.1, D being the diameter of the cross section of the envelope surface S, apart from the cutouts.
11. The brush according to claim 1, wherein the brush is chamfered at its ends.
12. A packaging and application device comprising: a container containing the product to be applied, a brush according to claim 1.
13. A method for manufacturing a brush according to the invention, comprising the steps of: producing a brush blank having a rectilinear twisted core, cutting the bristles so as to form the cutout(s) so as to obtain a brush according to claim 1, optionally curving the core.
14. The brush according to claim 1, wherein depth of the cutout varies relative to the twisted core along the longitudinal axes of the cutout and brush.
Description
(1) The invention may be better understood from reading the following detailed description of non-limiting illustrative embodiments thereof and from examining the appended drawing, in which:
(2) FIG. 1 shows an example of a packaging and application device according to the invention, in schematic longitudinal section,
(3) FIG. 2 is a schematic perspective depiction of an example of a brush according to the invention,
(4) FIG. 3 is a cross-sectional view on III in FIG. 2,
(5) FIG. 4 is a cross-sectional view on IV in FIG. 2,
(6) FIG. 5 is a cross-sectional view on V in FIG. 2,
(7) FIG. 6 shows an example of a method for manufacturing a brush according to the invention,
(8) FIG. 7 shows a variant method for manufacturing a brush according to the invention,
(9) FIG. 8 shows a variant method for manufacturing a brush according to the invention,
(10) FIG. 9 is a view similar to FIG. 5 of a variant brush,
(11) FIGS. 10A to 10G are views similar to FIG. 4 of variant brushes,
(12) FIG. 11 is a longitudinal section through a variant brush according to the invention,
(13) FIG. 12 is a view on XII of the brush in FIG. 11, and
(14) FIG. 13 is a schematic top view of a variant brush according to the invention.
(15) 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.
(16) 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.
(17) The applicator 3 comprises a stem 5 of longitudinal axis Y, which is provided at a distal end 5a of the stem with a brush 10 according to the invention, and at the other end with a gripping member 11 that 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.
(18) 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.
(19) The brush 10 may be fixed, in a conventional manner, in a housing provided at the distal end 5a of the stem 5, which is advantageously made of a thermoplastic material. The brush 10 comprises a twisted metal core 40 which is fixed at one end in the corresponding housing of the stem 5 by a portion of the core that does not have bristles, it being possible for said portion to have a length of around 8 mm.
(20) The core 40 carries bristles 41, the free ends of which define an envelope surface S of the brush 10, as illustrated in FIG. 2. As illustrated in FIG. 4, the bristles 41 extend along a length L.sub.1 of the core of preferably between 25 mm and 35 mm, in this case substantially equal to 30 mm.
(21) 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.
(22) As illustrated in FIG. 2, the envelope surface S comprises cutouts 45 extending longitudinally along an axis substantially parallel to the longitudinal axis X of the core 40. As can be seen in FIG. 3, the cutouts 45 extend along a length L.sub.2 greater than more than ⅔ of the length L.sub.1 of the part of the core 40 carrying the bristles 41; in this case the length L.sub.2 is greater than ¾ of the length L.sub.1.
(23) The envelope surface S, apart from the cutouts 45, has substantially the shape of a cylinder of revolution. 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, in this case substantially equal to 4.2 mm.
(24) The cutouts 45 are at a distance d from the longitudinal axis X, said distance being variable along their length L.sub.2, notably a continuously variable distance d. In longitudinal section, as illustrated in FIG. 3, the cutouts 45 have a profile that is concave towards the outside, notably in a circular arc. The radius of curvature r of the profile of the cutouts 45 is preferably between 40 mm and 65 mm, for example around 50 mm.
(25) The minimum distance d.sub.min from the longitudinal axis X is preferably between 2.5 and 3.5 mm, for example substantially equal to 3 mm. The ratio d.sub.min/R is preferably between 0.4 and 0.9, better still between 0.6 and 0.9, better still substantially equal to 0.7.
(26) In the example illustrated in FIGS. 2 to 5, the envelope surface S comprises four identical cutouts 45 that are distributed evenly around the core 40. The cutouts 45 have a flat bottom 47. As can be seen in FIG. 2, the width w of the cutouts 45, measured at the bottom 47 of the cutouts 45, is constant along the entire length L.sub.2 of the cutouts 45. The width w of the cutouts 45 is preferably between 1 mm and 4 mm, better still between 1.5 mm and 3.5 mm, in this case substantially equal to 2.3 mm.
(27) The cutouts 45 have flanks 49 that diverge towards the outside and form an angle α of between 35° and 45°, in this case substantially equal to 40°, between one another. The width W of the cutouts 45, measured at the surface of the cutouts 45, is thus greater than the width w of the cutouts 45. The ratio of the widths w/W is preferably between 0.8 and 0.7, in this case substantially equal to 0.77.
(28) As illustrated in FIGS. 2 and 3, the ends 52 of the envelope surface S are chamfered. This can make it easier for the brush 3 to pass through the wiper 20. The chamfer at the distal end and the chamfer at the proximal end are in this case different. The walls of the chamfer at the distal end are notably less inclined than that the walls of the chamfer at the proximal end.
(29) The cutouts 45 can be produced using a cutting tool 520, illustrated in FIGS. 6 to 8. The cutting tool 520 is preferably in the form of a cylinder, notably a cylinder of revolution. The cutting tool 520 comprises a cutting surface that comes into contact with the bristles 41 and cuts the bristles 41 so as to form a cutout 45. The width of the cutting surface of the cutting tool 520 defines the width w of the cutout 45. The cutting tool 520 comprises a longitudinal axis Z and is rotated about said longitudinal axis Z. This makes it easier to cut the bristles.
(30) In the example illustrated in FIG. 6, the bristles 41 are cut by moving the cutting tool 520 both in a direction A parallel to the longitudinal axis X and in a direction B perpendicular to the longitudinal axis X. The longitudinal axis Z is perpendicular to the width w of the bottom 47 of the cutout 45. The cutting surface is formed by the free base 54 of the cylinder forming the cutting tool 520. Such a cutting tool 520 makes it possible to obtain a cutout 45 having a flat bottom 47 in cross section.
(31) In the example illustrated in FIG. 7, the bristles 41 are cut by moving the cutting tool 520 both in a direction A parallel to the longitudinal axis X and in a direction B perpendicular to the longitudinal axis X. The longitudinal axis Z is parallel to the bottom 47 of the cutout 45. The cutting surface is formed by the lateral surface 56 of the cylinder forming the cutting tool 520. The shape of the generatrix of the cylinder makes it possible, in this case, to define a particular shape for the bottom 47 of the cutout 45. For example, if the generatrix is a straight line, the bottom 47 will be flat in cross section, and if the generatrix is concave towards the outside, the bottom 47 will be convex towards the outside in cross section.
(32) In the example illustrated in FIG. 8, the bristles 41 are cut by moving the cutting tool 520 about an axis perpendicular to the longitudinal axis X of the core and parallel to the bottom 47 of the cutout 45 in a direction C. The longitudinal axis Z is perpendicular to the bottom 47 of the cutout 45. The cutting surface is formed by the free base 54 of the cylinder forming the cutting tool 520. Such a cutting tool 520 makes it possible to obtain a cutout 45 having a flat bottom 47 in cross section.
(33) The example illustrated in FIG. 9 differs from that illustrated in FIGS. 2 to 5 in that the shape of the bottom 47 of the cutouts 45 is convex towards the outside. In cross section, the bottom 47 of the cutouts 45 can form a circular arc with a radius substantially equal to d. As described above, in order to produce such a bottom 47, the cutting tool 520 can be as illustrated in FIG. 7.
(34) The examples in FIGS. 10A to 10G differ from the one illustrated in FIGS. 2 to 5 by way of the shape of the envelope surface S.
(35) FIGS. 10A to 10G have axisymmetric shapes.
(36) In the example illustrated in FIG. 10A, the envelope surface S, apart from the cutouts, is peanut-shaped. It has a diameter that passes through a minimum 60 between two bulging portions 62 and 64, one 62 being proximal and the other 64 distal. The envelope surface S is symmetric with respect to the transverse plane of the minimum diameter. The cutouts 45 are made, for example, from one bulging portion 62 to the other 64, as illustrated.
(37) In the example illustrated in FIG. 10B, the envelope surface S, apart from the cutouts, is bomb-shaped. It has a diameter that passes through a maximum 70 close to the distal end at a circle of greatest diameter. The body of the brush 3 is frustoconical, being connected at its base that is coincident with the circle of greatest diameter to the distal end part of the brush 3, of ogival shape. The cutouts 45 extend, for example, from the proximal end to the part of greatest diameter.
(38) In the example illustrated in FIG. 10C, the envelope surface S, apart from the cutouts, is buoy-shaped. The envelope surface S is defined by two frustoconical portions 80 and 82 that are joined together by their base of greatest diameter. The cutouts 45 extend, for example, from the proximal end to the joint between the two frustoconical portions 80 and 82.
(39) In the example illustrated in FIG. 10D, the envelope surface S, apart from the cutouts, is defined by 3 frustoconical portions 90, 92 and 94 that are joined together by their bases. The frustoconical portion 90 is situated at the proximal end and the portion 94 is situated at the distal end. The portion 92 extends between the two end portions 90 and 94 and is attached to the proximal portion 90 by its base of greatest diameter and to the distal portion 94 by its base of smallest diameter. The cutouts 45 extend, for example, only along the central portion 92.
(40) In the example illustrated in FIG. 10E, the envelope surface S, apart from the cutouts, is in the form of an asymmetric peanut. It has a diameter that passes through a minimum 100 between two bulging portions 102 and 104, one 102 being proximal and the other 104 distal. The minimum 100 is closer to the distal end than to the proximal end. The bulging portions 102 and 104 have different greatest diameters, notably the greatest diameter of the portion 104 is smaller than the greatest diameter of the portion 102. The cutouts 45 are made, for example, from one bulging portion 102 to the other 104, as illustrated.
(41) In the example illustrated in FIG. 10F, the envelope surface S, apart from the cutouts, also has a bulging shape. It has a diameter that passes through a maximum 110. This maximum 110 is situated substantially at the centre of the portion of the core carrying the bristles. The distal end 114 and the proximal end 112 have different diameters; notably the diameter of the distal end 114 is smaller than that of the proximal end 112. The cutouts 45 extend, for example, from the distal end 114 to the proximal end 112.
(42) In the example illustrated in FIG. 10G, the envelope surface S, apart from the cutouts, has the overall shape of a diabolo with two frustoconical end portions 120 and 122 that are connected by their bases of greatest diameter to two cylindrical portions 124 and 126, respectively, which are themselves connected together by a portion 128 that narrows towards the centre. This portion 128 has a minimum diameter 130 substantially at the centre of the part of the core carrying the bristles. The cylindrical portions 124 and 126 have the same thickness and different diameters. The distal cylindrical portion 126 has a smaller diameter than the proximal cylindrical portion 124. The frustoconical portions 120 and 122 have the same thickness. The cutouts 45 are made, for example, from one cylindrical portion 124 to the other 126, as illustrated.
(43) The example in FIGS. 11 and 12 differs from that in FIGS. 2 to 5 in that the envelope surface S is not axisymmetric and in that it has only one cutout 45.
(44) The envelope surface S may have an angular sector 140 defined by bristles that are longer than the rest of the brush 3. The angular sector 140 extends along the entire length L.sub.1 of the brush 3 and may have, in longitudinal section, a profile with a variable height with respect to the longitudinal axis X, notably a profile in the form of a dorsal fin. Within the angular sector 140, the height of the envelope surface S can pass through a maximum 142 close to the proximal end. The rest of the envelope surface S, apart from the cutout 45, can have a symmetrical bulging shape with respect to a mid-plane M. The cutout 45 can extend along the envelope surface S from the proximal end to the distal end, somewhere other than the angular sector.
(45) In a variant, the cutout 45 can extend along the angular sector 140 from the proximal end to the distal end.
(46) The example in FIG. 13 differs from that in FIGS. 2 to 5 in that the cutouts 45 have a width w that is variable in two portions 150 and 152 and constant in a portion 154 extending between the portions 150 and 152. The portion 154 has a length L.sub.3 that makes up more than 50% of the length L.sub.2 of the cutout 45.
(47) Generally, the envelope surface can comprise a different number of cutouts and it is possible for the latter not to be identical to one another and/or distributed evenly around the core 40.
(48) In a variant, the envelope surface may have any other shape, which is or is not axisymmetric.
(49) The profile of the cutouts in longitudinal section may have angular points, and notably be formed by joined-together segments.
(50) 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.
(51) For example, the cutouts of the examples in FIGS. 10A to 12 can have a concave bottom as illustrated in FIG. 9.
(52) The expression “comprising a” should be understood as being synonymous with “comprising at least”.
