A molded plastic container comprising a hollow main body for containing a product

Abstract

The present invention relates to a molded preform for manufacturing a container made of thermoplastic material using a blow molding process, said preform comprising a main part or preform body configured to be blown to form a hollow main body of the container and a head part not intended to be deformed by blow molding and configured to form at least one neck of the container, characterized in that the head part also comprises at least a portion of a shoulder of the container joining the main body to the neck, said shoulder carrying at least one locking lug extending projecting at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck. Figure for abstract: Fig. 3

Description

Title of the invention: Molded plastic container comprising a hollow main body intended to contain a product

[0001] The present invention relates to a molded preform for the manufacture of a container made of thermoplastic material using a blow molding process and to such a container. The present application relates more particularly to containers intended to receive and dispense a cosmetic product such as bottles, flasks, applicator assembly reservoirs such as roll-on applicators.

[0002] There are many techniques for manufacturing molded containers from thermoplastic material. A particularly interesting technique is the manufacture by blow molding of a preform previously made by molding the thermoplastic material, for example PET, PE, PP, PS, POM, PVC. The preform can in particular be manufactured by an injection or extrusion process.

[0003] Generally, a preform comprises a preform body intended to be expanded by blow molding in order to form a main body of the container and a preform head which is intended to form a neck of the container and is not intended to be deformed by the blow molding operation. More specifically, the preform head is intended to allow the positioning and holding of the preform body inside the blow mold. The preform head is also intended to allow the insertion of a blow cannula inside the preform body.

[0004] Production of the preform by injection is generally preferred when the container must be manufactured with a neck provided with a thread or other means allowing the attachment of a cap such as a dispensing head or a closing lid (screw cap).

[0005] Often intended to be removable, it may be desirable to secure the unscrewing of said cap so as to avoid any accidental opening. This is particularly desirable when the dispensing head comprises several removable elements intended to be detached from the container separately and / or for different reasons. Thus, the example of a dispensing head may be given comprising, on the one hand, a base intended to be removed from the container to proceed with its refilling or filling, and on the other hand a cover, mounted on the base and intended to be removed each time it is used.

[0006] To do this, so-called “child safety” systems are known as described and illustrated, for example, in documents US11174081B2 and DE202021106745U1 for ball applicators or US5865330A for a bottle cap. Generally, such a system comprises locking lugs arranged on a part of the neck of the container and associated with deformable parts of the cap. In a rest position, the deformable parts abut against a corresponding surface of the lug in order to oppose the unscrewing of the cap. Pressure from the user on an appropriate area of ​​the cap allows said deformable parts to be deformed and thus to move them away from the lug, releasing the rotation of the cap and allowing it to be unscrewed.

[0007] In document US5865330A, the locking lugs are carried by a collar attached to the neck. The deformable zones are produced in the form of flexible tabs capable of cooperating directly with the locking lugs. The same applies in document US11174081B2 where the locking lugs are also attached to the container, either on a surface of a shoulder joining the body to the neck, or on a plate extending from a base of the neck.

[0008] In document DE202021106745U1, the locking elements are produced on a wall of the neck, which can hinder the production of the screw thread of the cap. Furthermore, the deformation zones are formed by the skirt of the cap and are deformed by pressing on unlocking surfaces oriented at 90° to the lugs.

[0009] There is a need to facilitate the production of such locking lugs and in particular to allow their integral production with the container, and this from the manufacture of the preform by molding so as to be able to produce the finished container by a blowing process.

[0010] To this end, the present application relates to a molded preform for the manufacture of a container made of thermoplastic material according to a blowing process, said preform comprising a main part or preform body configured to be blown in order to form a hollow main body of the container and a head part not intended to be deformed by the blowing and configured to form at least one neck of the container.

[0011] In accordance with the present application, the head part also comprises at least a portion of a shoulder of the container joining the main body to the neck, said shoulder carrying at least one locking lug extending in projection at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck.

[0012] Thus, by producing a preform in which at least a portion of the shoulder of the container is integrated into the preform head which is not intended to be deformed during blowing of the preform body, it is possible to include therein during molding of the preform the locking lugs which will form a locking system with a cap equipped with corresponding deformation zones.

[0013] In other words, unlike the existing practice in which the preform body is blown and integrally forms both the main body of the container and its shoulder joining said main body to the neck, the shoulder of the container and its locking lugs are injected into the preform head, in accordance with the desired final shape, without being integrated into a part of the preform intended to be deformed during blowing.

[0014] It should be noted that by integrating the shoulder into the preform head, it is necessary to use additional plastic material. It follows that the final mass of the container will be higher than a container obtained by blow molding a preform in which the shoulder is formed purely by expansion of the body of the preform. Its mass will, however, remain significantly lower than if it had been necessary to produce the container directly in its final shape by molding (injection) without blow molding, or even to produce it by injection blow molding by adding the lugs or a part carrying the lugs. This also avoids providing an additional collar to the head part for producing the locking lugs.

[0015] During the blowing step, the body of the preform is deformed and part of the material is reattached under the injected shoulder, not deformed during blowing. The blowing mold will advantageously be designed so that the shoulder is in surface continuity with an external surface of the main body of the container.

[0016] It should be noted that the preform is understood as the result of the molding step shaping it before the blowing step. The preform may be an individualized product that can be stored and / or moved between the molding step and the blowing step. This is particularly the case in injection-blow molding processes conventionally comprising two distinct steps. The preform undergoes, in a more or less short time, or even immediately after the molding step, the blowing step intended to transform it into a finished container. The preform may also be a temporary, non-individualized intermediate product.This is particularly the case in extrusion-blow molding processes which can be implemented continuously in a single step, the preform then being constituted by the parison part around which the blow mold is positioned, even if this part is only separated from the rest of the extruded material after blowing.

[0017] According to one embodiment, the portion of the head of the preform intended to form the shoulder of the container is produced in the form of a collar extending in projection from the preform at a junction between the neck and the body of the preform.

[0018] Preferably, the collar intended to form the shoulder of the container projects in a direction substantially transverse to a longitudinal axis of the preform. Advantageously, the part intended to form the shoulder of the container has an essentially flat external upper surface. By upper, it is meant that the surface is oriented towards an opening of the neck. By lower, it is meant a surface oriented towards a bottom of the container or of the body of the preform.

[0019] Preferably again, a longitudinal axis of the preform coincides with the longitudinal axis of the neck.

[0020] According to one embodiment, the locking lug has at least one downstream stop surface substantially transverse to a direction of unscrewing of the thread of the neck, said downstream stop surface being configured to cooperate with a complementary locking element of a cap in order to prevent its unscrewing in the absence of an elastic deformation radially separating said complementary locking element from the lug.

[0021] Preferably, the locking lug has an upstream profile configured to allow the passage by elastic deformation of at least one complementary locking element of the cap in a screwing direction. By upstream, we mean a position more advanced along the thread in the direction of the opening of the neck, that is to say closer to the opening of the neck. Conversely, downstream designates a position closer to the preform body or the body of the container along the thread.

[0022] Preferably again, the head part of the preform intended to form the shoulder has at least two diametrically opposed locking lugs.

[0023] The present invention also relates to a container molded from a thermoplastic plastic material that can be obtained by blow molding a preform according to the present application. The container comprises a hollow main body intended to contain a product and surmounted by a shoulder leading to a threaded neck. The shoulder has at least one locking lug extending in projection at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck. The container is characterized in that said lug is integral with the shoulder.

[0024] According to one embodiment, the shoulder has a material bonding surface between a non-blown molded external upper part and a blown internal lower part.

[0025] The present application also relates to a packaging and dispensing assembly for a product, characterized in that it comprises a cap capable of cooperating removably with the neck of a container according to the application. The cap has at least one locking element that can be moved elastically between a rest position in which the locking element abuts against the locking lug of the container in an unscrewing direction, and a spaced position in which the locking element is spaced from the corresponding locking lug of the container and allows said cap to be unscrewed.

[0026] According to a preferred embodiment, the cap is a ball holder, the assembly being capable of forming a ball or roll-on applicator. Advantageously complementary, the cap, and in particular the ball holder, has an external thread capable of cooperate with a closing hood of said cover.

[0027] The invention may be better understood by reading the detailed description which follows, a non-limiting example of its implementation, and by examining the attached drawing, in which:

[0028] [Fig. 1] represents a packaging and distribution assembly according to the present application,

[0029] [Fig.2] represents a longitudinal sectional view of the whole of [Fig.l],

[0030] [Fig.3] is a schematic representation seen from the side of a container forming part of the assembly of [Fig.l],

[0031] [Fig.4] is a schematic representation seen from above of the container of [Fig.3],

[0032] [Fig.5] is a schematic representation in longitudinal section of a cap of ball-holder type forming part of the assembly of [Fig.l],

[0033] [Fig.6] is a schematic representation seen from above of the ball-carrying cap of [Fig.5],

[0034] [Fig.7] is a schematic representation of a preform arranged inside a blow mold for producing the container of [Fig.3].

[0035] [Fig. 1] shows an example of a packaging and dispensing assembly 100 according to the present application in the form of a ball or “roll-on” applicator assembly.

[0036] It should be noted that although illustrated by a refillable ball applicator assembly, the present invention is not limited to a particular type of dispenser assembly and can in particular be implemented on pump bottle type assemblies or others.

[0037] The applicator assembly comprises a container 120 on a neck 121 of which is mounted a dispensing head 130 forming a cap. The dispensing head 130 comprises a base formed by a ball holder 131 removably mounted on the neck 121, and a cover 132 removably mounted on the ball holder 131.

[0038] The assembly 100 forms a refillable ball applicator as generally described for example in documents DE202021106745U1, ES2413163B1 or WO2021155454A1.

[0039] Thus, the ball holder 131 forming the base of the cap is intended to be removed from the container 120 in order to fill or refill it, or even replace it with a full container, the ball holder 131 then being mounted on the neck 121 of another container 120. The cover 132 is intended to be removed from the ball holder 131 during more frequent use of the applicator assembly 100.

[0040] The assembly and disassembly of the ball holder 131 forming the base of the cap and the hood 132 is carried out in particular by screwing. To do this, the neck 121 of the reservoir has an external thread 122 capable of cooperating with an internal thread 134 completed additional to an inner skirt 133 of the ball holder. Similarly, the cover 132 has an internal thread 136 capable of cooperating with a complementary external thread 135 carried by an external peripheral surface 137 of the ball holder 131. In a complementary manner, the neck 121 has end-of-travel stops 127 for screwing intended to cooperate with complementary stops carried by the inner skirt 133 of the ball holder 131.

[0041] As indicated previously, it is desirable to secure the disassembly of the ball-holder base 131 so as to prevent any accidental disassembly, in particular when disassembling the cover 132. A first solution is to provide unscrewing threads in opposite directions. In doing so, the disassembly of the cover is carried out in a first direction of rotation while to disassemble the cap it will be convenient for the user to unscrew by turning in the other direction. This is however counter-intuitive for the user. Furthermore, if the user, or the factory during a first assembly, screws the cover too tightly, it is possible to unscrew the ball-holder (and vice versa).

[0042] Another solution is to design the mounting threads of the base of the cap and the hood in such a way that they have different unscrewing forces, the unscrewing force required for the ball-holder cap having to be significantly greater than the unscrewing force required for the hood. Such threads are complex to design and produce because the targeted unscrewing forces must remain acceptable to the user while being sufficiently different and outside the manufacturing tolerances.

[0043] Thus, it is preferable that the cover 132 and the base 131 of the cap are unscrewable in the same direction as in the present example, in particular in the conventional counterclockwise direction and preferably with similar unscrewing forces.

[0044] The removable attachment of the base is secured by a “child safety” type mechanism. Thus, the cap formed by the ball holder 131 has at least one locking element that can be moved elastically between a rest position in which the locking element abuts against a corresponding locking lug of the container in an unscrewing direction, and a spaced position in which the locking element is spaced from the locking lug of the container and allows said cap to be unscrewed.

[0045] More particularly, the movable locking element is arranged in an external skirt 137 of the ball-carrying cap 131. In this case, the movable locking element is in the form of a flexible tab 138, the spaced-apart position being a position in which the flexible tab 137 is pushed radially towards the inside of the cap.

[0046] The cap has two movable and diametrically opposed locking elements, i.e., two flexible tabs 138.

[0047] The locking elements of the ball-holder cap 131 are intended to cooperate with locking lugs 151 arranged on the container 120 which will be described.

[0048] The container 120 is a container molded from a thermoplastic material that can be obtained by blow molding a preform 10 ([Fig.7]). The container 120 comprises a hollow main body 129 intended to contain the cosmetic product to be dispensed through the ball-holder cap 131, the hollow main body being surmounted by a shoulder 123 leading to the threaded neck 121 of the container.

[0049] In accordance with the present application, the shoulder 123 carries the locking lugs 151, said lugs projecting at a non-zero distance from the neck 121 from an external surface of the shoulder 123 in a direction substantially parallel to a longitudinal direction of the neck 121.

[0050] The container 120 is characterized in that the lugs 151 are integral with the shoulder 123. More precisely, as explained previously, the lugs 151 are provided directly in a molded preform head, including at least an upper portion of the shoulder carrying said lugs, and not intended to be deformed during the blowing operation. The upper portion of the shoulder carrying the lugs 151 is produced in the form of a collar 151b extending radially in projection relative to a longitudinal axis of the preform and located substantially at a junction between the preform head (forming the neck 121, not deformed during blowing) and the preform body (forming the body 122 of the container 120, deformed during blowing).

[0051] Each locking lug 151 has at least one downstream stop surface substantially transverse to a direction of unscrewing of the thread 122 of the neck 121 and capable of cooperating with a complementary locking element of the ball-carrying base 131 of the cap 130 in order to prevent its unscrewing in the absence of an elastic deformation radially separating the associated locking tab 138 from the ball-carrying cap 131.

[0052] Each locking lug 151 also has an upstream profile configured to allow the passage of the associated locking tab 138 in a screwing direction by elastic deformation.

[0053] The preform 10 intended to be blown to obtain the final container comprises a main part or preform body configured to be blown to form the hollow main body 122 of the container 120 and a head part not intended to be deformed by the blowing and configured to form the neck 121 of the container 120. In accordance with the present application, the head part also comprises a portion of a shoulder 123 of the container 120 joining the main body 122 to the neck 121 and said shoulder 123 carries the locking lugs 151. As for the final container, the locking lugs project at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck.

[0054] The portion of the head of the preform 10 intended to form a part of the shoulder 123 of the container 120 is produced in the form of a collar 10b extending projecting from the preform at a junction between the neck and the body of the preform to be blown. The collar 10b extends projecting in a direction substantially transverse to a longitudinal axis of the preform 10 which coincides with the longitudinal axis of the neck.

[0055] Thus, during the blowing operation, the preform 10 is placed in the blowing mold M2, the shoulder part being located at the interface between a holding part M2a of the mold and a blowing part M2b of the mold.

[0056] More specifically, the blow mold M2 is made so as to have a first volume inside which the body of the preform is arranged in order to be deformed therein by blowing so as to adopt the shape of said first volume of the blow mold. The blow mold comprises a second, upper volume, intended to allow the preform to be held in the mold by means of the preform head. Since the head of the preform is not intended to be deformed by blowing, this second volume has a complementary shape with the head of the preform, unlike the first volume which does not have a complementary shape with the body of the preform before it is blown but has the final shape of the main body 122 of the container 120.

[0057] The first and second volumes obviously communicate with each other at the junction between the preform head and the preform body.

[0058] Thus, when the preform is placed in the blow mold, the neck is held in the second volume, corresponding to its shape, while the preform body projects into the first volume. An upper part of the shoulder carrying the lugs is also located in the second volume while a lower surface of this part is flush with the first volume.

[0059] When the preform body is blown, it deforms and expands to fit the internal shape of the mold. In doing so, a portion of the blown plastic material comes to stick against the lower surface of the shoulder portion located at the interface between the first (blowing) volume and the second (holding) volume. Consequently, the shoulder of the final container may have a material sticking surface between a non-blown molded external upper portion (part of the preform head) and a blown internal lower portion (belonging to the preform body).

[0060] [Fig.7] shows, on the right-hand side, the preform 10 compared to its injection mold M1 allowing its initial manufacture, and on the left-hand side, as arranged in its blow mold M2 to obtain the container by blowing the body of the preform.

Claims

Claims

1. Preform (10) molded for the manufacture of a container (120) made of thermoplastic material according to a blow molding process, said preform comprising a main part or preform body configured to be blown in order to form a hollow main body (129) of the container and a head part not intended to be deformed by the blow molding and configured to form at least one neck (131) of the container, characterized in that the head part also comprises at least a portion of a shoulder (123) of the container joining the main body to the neck, said shoulder carrying at least one locking lug (151) extending projecting at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck.

2. Preform (10) according to claim 1, characterized in that the portion of the head of the preform intended to form a part of the shoulder (123) of the container (120) is produced in the form of a collar (10b) extending in projection from the preform at a junction between the neck and the body of the preform to be blown.

3. Preform (10) according to claim 2, characterized in that the collar (10b) intended to form a part of the shoulder (123) of the container (120) extends projecting in a direction substantially transverse to a longitudinal axis of the preform.

4. Preform (10) according to any one of claims 1 to 3, characterized in that a longitudinal axis of the preform coincides with the longitudinal axis of the neck (121).

5. Preform (10) according to any one of claims 1 to 4, characterized in that the locking lug (151) has at least one downstream stop surface substantially transverse to a direction of unscrewing of the thread (122) of the neck (121), said downstream stop surface being capable of cooperating with a locking element (138) complementary to a cap (130) in order to prevent its unscrewing in the absence of an elastic deformation radially separating said complementary locking element from the lug.

6. Preform (10) according to any one of claims 1 to 5, characterized in that the locking lug (151) has an upstream profile configured to allow the passage by elastic deformation of at least one locking element (138) complementary to a cap (131) in a screwing direction.

7. Preform (10) according to any one of claims 1 to 6, characterized in that the head part of the preform intended to form the shoulder has at least two diametrically opposed locking lugs (151).

8. Container (120) molded from thermoplastic material obtained by blow molding a preform according to any one of claims 1 to 7, the container comprising a hollow main body (129) intended to contain a product and surmounted by a shoulder (123) leading to a threaded neck (121), the shoulder having at least one locking lug (151) extending projecting at a non-zero distance from the neck from an external upper surface of the shoulder in a direction substantially parallel to a longitudinal direction of the neck, the container being characterized in that said lug is integral with the shoulder.

9. Container (120) according to claim 8, characterized in that the shoulder (123) has a surface for bonding material between a non-blown molded external upper part and a blown internal lower part.

10. Packaging and dispensing assembly (100) for a product, characterized in that it comprises a cap (130) capable of cooperating removably with the neck (121) of a container (120) according to any one of claims 8 or 9, the cap having at least one locking element (138) elastically movable between a rest position in which the locking element abuts against the locking lug (151) of the container in an unscrewing direction, and a spaced position in which the locking element is spaced from the locking lug of the container and allows unscrewing of said cap.

11. Assembly (100) according to claim 10, characterized in that the cap (130) is a ball holder (131), the assembly being capable of forming a ball or roll-on applicator.

12. Assembly (100) according to any one of claims 10 or 11, characterized in that the cap (130), in particular the ball holder, has an external thread capable of cooperating with a cover (132) for closing said cap.

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