WO2019096842A1

WO2019096842A1 - Applicator, for the application of a cosmetic product, comprising a foam, and associated assembly method

Info

Publication number: WO2019096842A1
Application number: PCT/EP2018/081217
Authority: WO
Inventors: Marcel Sanchez
Original assignee: L'oreal
Priority date: 2017-11-16
Filing date: 2018-11-14
Publication date: 2019-05-23
Also published as: FR3073374B1; FR3073374A1

Abstract

The cosmetic product applicator comprises a stem (20) and at least one foam (22) arranged on the stem and intended for the application of said product. Said foam (22) is secured to the stem (20) by at least one weld zone, an exterior surface of said foam having at least one corresponding recess (40) located in line with said weld zone.

Description

Applicator, for the application of a cosmetic product, comprising a foam, and associated assembly method

The present invention relates to an applicator for the application of a cosmetic product.

The expression“cosmetic product” is understood to mean a product as defined in Regulation (EC) No 1223/2009 of the European Parliament and of the Council of 30 November 2009 relating to cosmetic products.

The invention is particularly suitable for the application of a cosmetic product, such as a make-up product or lip-care product, particularly lip gloss.

A very large number of specialized applicators for the application of a cosmetic product are known, which comprise a stem integral with a grip member and with at least one application member comprising a foam secured to the end thereof. By its very nature, the foam of the application member is capable of holding the product to be applied both on its surface and also within its depth through a capillary effect.

Patent application FR-A1-2 762 494 describes, for example, an applicator comprising two product application members, one of which is constituted of foam. This earlier document makes provision for this foam to be secured to the other application member by adhesive bonding, welding, force-fitting or, alternatively, by snap-fitting.

The present invention aims to propose an applicator comprising a foam, wherein mounting of this foam is independent of the existence or non-existence of another application member and wherein the amount of product that may be held prior to application is increased.

A subject of the invention is a cosmetic product applicator comprising a stem and at least one foam or foam piece arranged on the stem and intended for the application of said product. Said foam is secured to the stem by at least one weld zone. An exterior surface of said foam has a corresponding recess located in line with said weld zone.

As the applying foam is secured directly to the stem of the applicator, this applicator may optionally be equipped with another application member mounted on the stem without there being a need for this securing mode to be modified. Furthermore, forming the weld zone(s) by means of an ultrasonic welding operation, so as to join the foam to the stem, is particularly advantageous insofar as this makes it possible, in the course of this operation, to create one or more recesses that form reservoirs for receiving and holding the product to be applied.

Indeed, in order to carry out this ultrasonic welding the foam is pinched by the sonotrode of an ultrasonic generator, which has the effect of forming the recess(es). “Recess” is understood to mean a depression or a part that is sunken relative to the exterior surface of the foam. A recess corresponding to each weld zone is located at said weld zone.

With the presence of the recess(es) forming product reservoirs, the amount of product that can be applied is increased.

At least in the zone(s) of the recess(es), the foam is made of a material that can be ultrasonically welded, for example a polyurethane foam.

Said recess preferably extends into the thickness of said foam in the direction of the stem without opening out on said stem.

In other words, the recess comprises a bottom that is offset towards the interior relative to the exterior surface of the foam and offset towards the exterior relative to the exterior surface of the stem. The provision of one or more blind recesses promotes holding of the product prior to application.

The applicator may further comprise a grip member integral with the stem on the side opposite said foam. In one particular embodiment, the stem comprises a proximal portion integral with said grip member, and a distal portion provided with at least one flat end part onto which said foam is secured. Such an end part with a flat shape promotes contact with the foam and thus good securing of the foam on the stem.

To facilitate the operations involved in manufacturing the applicator, the distal portion may be formed so as to allow it to be assembled with the proximal portion. Thus, the flat end part of the distal portion may be welded with the foam, and then the distal portion may be assembled with the proximal portion. An end of one of the proximal and distal portions may, for example, be equipped with a housing inside which an end of the other portion engages in order for these portions to be assembled.

In a variant, the portions may be made as a single component, for example by moulding.

The distal portion preferably extends as a continuation of the stem proximal portion of the applicator. In a variant, it is possible to provide an arrangement in which the elongation axis of the stem proximal portion forms a non-zero angle with the elongation axis of the distal portion.

In one particular embodiment, at least two radially opposed recesses are formed on the exterior surface of said foam with respect to a longitudinal elongation axis of the stem.

The invention also relates to a cosmetic product packaging and application device comprising a receptacle, for storing said product, and an applicator as defined previously and mounted in a removable manner between a take-up position in which said foam is located inside the reservoir and capable of being at least partially placed in contact with the cosmetic product contained in the receptacle, said recess forming a reservoir for receiving and holding said product, and an application position in which the applicator is separate from the receptacle and may be brought into contact with a part of the human body. The grip member of the applicator is preferably configured such that the receptacle can be sealingly closed in the take-up position.

The invention also relates to a method for assembling a cosmetic product applicator of the type comprising a stem and at least one foam secured to the stem and intended for the application of the product, the method comprising the following steps:

- applying the sonotrode of an ultrasonic generator against the exterior surface of the foam by pinching said foam locally,

- welding the foam ultrasonically to the stem, and

- forming said recess on the exterior surface of the foam at the time of pinching said foam locally and of ultrasonic welding.

The present invention will be better understood from studying the detailed description of one embodiment that is given by way of entirely non- limiting example and is illustrated by the appended drawings, in which:

- Figure 1 is a view in longitudinal section of a packaging and application device according to one exemplary embodiment of the invention,

- Figure 2 is a partial perspective view of an applicator of the device of Figure 1 comprising an application foam,

- Figure 3 is a partial perspective view of the applicator of Figure 2 without the application foam, and

- Figure 4 is a partial sectional view of the applicator of the device of Figure

2. Figure 1 shows a device, denoted by the overall reference numeral 10, which is intended to allow the packaging and application of a cosmetic product.

The cosmetic product to be applied may, for example, be a make-up or care product, and in particular a lip gloss intended to be applied to a user’s lips.

The device 10, of longitudinal axis X-X’, is shown in a position that is presumed to be vertical. The device 10 comprises a product applicator 12 and a receptacle 14 containing the cosmetic product to be applied (not shown).

The receptacle 14, of axis X-X’, delimits, within, an internal volume or reservoir 16 for storage of the cosmetic product. The receptacle 14 comprises an end forming a bottom and an open opposite end forming a neck 18 that delimits an opening for access to the internal reservoir 16. In the exemplary embodiment illustrated, the receptacle 14 has a circular cross section. In a variant, the receptacle 14 may have a cross section that is polygonal, in particular square, or, alternatively, an oval cross section.

The applicator 12, of axis X-X’, comprises a stem 20, a foam 22 carried by the stem 20 and forming a product application member, and a grip member 24 integral with the stem 20 on the side opposite the foam 22. The foam 22 is thus joined to the grip member 24 by means of the stem 20.

The grip member 24 of the applicator is configured in order to form a cap suitable for removably closing the receptacle 14 and, more precisely, the opening for access to the reservoir 16 of the receptacle. When the grip member 24 is in the position in which the receptacle 14 is closed, a part of the stem 20 and a part of the foam 22 are located inside the reservoir 16 of the receptacle. In order to provide removable mounting on the receptacle 14, the grip member 24 here comprises an inside thread that engages with an outside thread on the neck 18 of the receptacle. Alternatively, it is possible to provide other types of removable securing, for example by clip-fastening.

The device 10 also comprises a wiper member 26 secured inside the neck 18 of the receptacle and provided for wiping the stem 20 and the foam 22 when the applicator 10 is disengaged from the receptacle. The wiper member 26 here comprises an annular wiper lip 28 extending obliquely in the direction of the stem 20 and, by means of its free end, defining a wiper opening.

In the exemplary embodiment illustrated, the stem 20 of the applicator, of axis X-X’, comprises a first, proximal portion 30, integral with the grip member 12, and a second, distal portion 32 produced separately from the proximal portion 30 and secured thereto. The proximal portion 30 and the grip member 12 are here produced as a single component, for example by moulding from a thermoplastic material, for example from polybutylene terephthalate (PBT) or polyethylene (PE), from thermoplastic elastomer such as Hytrel®, etc.

The distal portion 32 of the stem may also be produced by moulding from plastics, for example from polybutylene terephthalate (PBT) or polyethylene (PE), from thermoplastic elastomer such as Hytrel®, etc. The distal portion 32 carries the foam 22 and is an axial extension of the proximal portion 30. The distal portion 32 is secured to the proximal portion 30 on the side opposite the grip member 24.

The distal portion 32 comprises a mount 34 that engages on the proximal portion 30, and an end part 36 to which the foam 22 is secured. The end part 36 extends the mount 34 on the side opposite the proximal portion 30. As may be seen in Figure 3, the end part 36 of the distal portion of the stem has a flat form. This makes it possible to promote contact with the foam 22. In the exemplary embodiment illustrated, the end part 36 has a rectangular cross section. Alternatively, the end part 36 may have a square cross section. In other variants, it is, however, possible to provide other profiles for the end part 36, for example circular, hexagonal, or oval, etc.

With reference, now, to Figure 4, the foam 22 of the applicator comprises a longitudinal blind opening 38 inside which the end part 36 of the distal portion of the stem extends. This makes it possible to prevent the user injuring herself with the free end of the end part 36 of the distal portion of the stem.

The foam 22 is in the form of a block. In the exemplary embodiment illustrated, the foam 22 has a cylindrical form. It is possible to provide other forms, for example frustoconical, domed, parallelepipedal, etc.

As indicated previously, the foam 22 is secured to the distal portion 32 of the stem. The foam 22 is produced from a material that is suitable for being welded using ultrasound, for example a polyurethane foam or, alternatively, a polyethylene foam. The foam 22 may have open or semi-open cells.

The foam 22 is secured to the distal portion 32 by ultrasonic welding. As may be seen in Figures 2 and 4, a plurality of recesses 40 is formed on the exterior surface of the foam 22. These recesses 40 are created when the foam 22 is ultrasonically welded to the distal portion 32 of the stem.

Indeed, to secure the foam 22 to the stem 20, in a first step the sonotrode of an ultrasonic generator is applied against the exterior surface of the foam 22, pinching the foam locally between the sonotrode and a counter-bearing surface generally known as the anvil of the ultrasonic welding device.

Next, in a second step, ultrasonic vibration is applied using the sonotrode. Dissipation of the vibrations gives rise to local heating capable of leading to welding of the foam 22 and of the stem 20 by local fusion of one and/or the other of the materials, in particular fusion of the material of the stem 20 and/or of the foam 22. Weld zones 42 (shown schematically in black) joining the foam 22 and the stem 20 are thus created.

In a third step, the generation of ultrasonic vibrations is halted and the pressure applied to the foam 22 is maintained during cooling. Lastly, in a final step, the sonotrode is withdrawn from the foam.

The recesses 40 formed on the foam thus correspond to the impressions made by the sonotrode of the ultrasonic generator and the anvil of the welding device. For each weld zone 42, a recess 40 is located radially in line with this zone. In other words, each recess 40 is located in the radial extension of the corresponding weld zone 42.

In the exemplary embodiment illustrated, the recesses 40 are in the form of rectangular slots with constant dimensions. The recesses 40 may, as a variant, have other forms, for example square, circular, hexagonal, etc., and/or have variable dimensions. The recesses 40 are here arranged in two radially opposed rows, each row comprising three recesses. With regard to this aspect, also, it is possible to obtain other arrangements for the recesses 40.

Each recess 40 extends radially into the thickness of the foam 22 without opening out on the distal portion 32 of the stem. Each recess 40 comprises a bottom wall 40a that is offset radially towards the interior relative to the exterior surface of the foam and offset radially towards the exterior relative to the distal portion 32 of the stem. Each recess 40 also comprises two opposite end edges and two opposite lateral edges (not referenced) delimiting said recess respectively in the axial direction and in the circumferential direction. These edges are joined to the bottom wall 40a. By way of indication, the depth of the recesses 40 may be between 10% and 70% of the thickness of the foam 22.

In practice, when the foam 22 of the applicator is plunged inside the reservoir 16 of the receptacle, it is loaded with product and the recesses 40 are likewise filled with product. The recesses 40 thus form chambers or reservoirs for receiving and holding the product. As compared with conventional applicators, the amount of product that may then be deposited at the time of application is thereby increased.

The invention has been illustrated on the basis of an applicator comprising a single application member formed by the foam. It is not a departure from the scope of the present invention for the applicator to comprise, in addition to the foam, at least one other application member arranged on the stem.

Claims

1. Cosmetic product applicator comprising a stem (20) and at least one foam (22) arranged on the stem and intended for the application of said product, characterized in that said foam (22) is secured to the stem (20) by at least one weld zone, an exterior surface of said foam having a corresponding recess (40) located in line with said weld zone.

2. Applicator according to Claim 1, wherein said recess (40) extends into the thickness of said foam (22) in the direction of the stem (20) without opening out on said stem.

3. Applicator according to Claim 1 or 2, further comprising a grip member

(12) integral with the stem (20) on the side opposite said foam (22).

4. Applicator according to Claim 3, wherein the stem (20) comprises a proximal portion (30) integral with said grip member, and a distal portion (32) provided with at least one flat end part (36) onto which said foam is secured.

5. Applicator according to Claim 4, wherein the distal portion (32) is formed so as to allow it to be assembled with the proximal portion (30).

6. Applicator according to Claim 4 or 5, wherein the distal portion (32) extends as a continuation of the proximal portion (30).

7. Applicator according to any one of the preceding claims, wherein at least two radially opposed recesses (40) are formed on the exterior surface of said foam with respect to a longitudinal elongation axis of the stem.

8. Applicator according to any one of the preceding claims, wherein said foam (22) is made of polyurethane at least in the zone(s) of the recess(es) (40).

9. Cosmetic product packaging and application device comprising a receptacle (14), for storing said product, and an applicator (10) according to any one of the preceding claims mounted in a removable manner between a take-up position in which said foam (22) is located inside the reservoir and capable of being at least partially placed in contact with the cosmetic product contained in the receptacle (14), said recess forming a reservoir for receiving and holding said product, and an application position in which the applicator is separate from the receptacle (14).

10. Method for assembling a cosmetic product applicator according to any one of Claims 1 to 8, the method comprising the following steps: applying the sonotrode of an ultrasonic generator against the exterior surface of the foam by pinching said foam locally,

welding the foam ultrasonically to the stem, and

forming said recess on the exterior surface of the foam at the time of pinching said foam locally and of ultrasonic welding.