EP0966898A2

EP0966898A2 - Mechanical Filling process of a container for cosmetic products

Info

Publication number: EP0966898A2
Application number: EP98203640A
Authority: EP
Inventors: Sergio Crosta
Original assignee: Laffon SpA
Current assignee: Laffon SpA
Priority date: 1998-06-22
Filing date: 1998-10-28
Publication date: 1999-12-29
Also published as: IT1301771B1; EP0966898A3; ITMI981420A1

Abstract

Mechanical filling process of a container for cosmetic products, wherein:

during a first phase, a doughy, hot cosmetic product is fed, under pressure (P1), into a chamber (20) which has a volume variable between zero and the final value, the chamber (20) is also provided with a mobile wall (21a),

and during a second phase, the product, which has been fed into said chamber (20), is cooled;

the process is characterised in that:

the chamber (20), fed by the filling product, is the chamber of a forming die (17); the mobile wall (21a) of the chamber (20) is subjected to a predefined counter-pressure (P2) during the first phase, and

during a third phase, the product (28), which has been held and cooled into said chamber (20) of said die (17), is transferred into the cup (34) of a final container (33).

Description

The present invention refers to a mechanical filling process of a container for cosmetic products, in particular of a pencil.
In general, the cosmetic products are placed into suitable containers having cylindrical or similar shape and into flat containers, inside corresponding cups or inserts.
In the flat containers, the product is put inside the insert and then it is flattened so as to fill the insert and finally said product is compacted to eliminate the presence of air bubbles and to be precisely positioned inside said insert.
In other type of container, having cylindrical or similar shape as for instance lipsticks, pencils, etc., the products are realised in the form of a stick or of a more or less thin cylindrical element.
These products are realised to be placed in the corresponding containers either by forming the stick in suitable dies or by directly casting the product into the container, or by extrusion.
The pastel or the lead are cast into a die and are then inserted in the corresponding cup of the container.
During the filling of the die or of the cup, bubbles are formed within the creamy or doughy product, the consequent brittleness and the gaps inside the product can cause the break of the pastel during its use.
Through a compacting operation of said products, said inclusion could be eliminated, but at the moment, said process has not been developed yet.
The document EP-A-723 880 describes a manufacturing process for cosmetic pencils which is related to the preamble of claim 1. In fact, said process provides that a filling cosmetic product is fed within a chanter and, during a first phase, the product is doughy, hot and under pressure. Then, the product is cooled.
The EP-A-686 468 document describes a molding process for lipsticks, while the US-A-5 316 712 document discloses a manufacturing process of a solid cosmetic composition.
The general purpose of the present invention is to overcome the technical problems associated with the known technique in a very simple economic and particularly functional manner.
Another purpose is to completely eliminate the presence of air within the product, and to make said product more stable and less fragile.
According to the present invention and to the above mentioned purposes, a mechanical filling process of a container for cosmetic products, having the features disclosed in the attached claims, has been realised.
The structural and functional features, as well as the advantages of the present invention compared with the known art, will be better understood and more evident from the following description referred to the attached drawings, which show examples of a mechanical filling process of a container for cosmetic products which are realised according to the invention.
In said drawings:
Figure 1 is a schematic view of an apparatus wherein a first group of the invention phases can be realised;
Figure 2 is an enlarged schematic view of a die which is used, during a first phase, in the apparatus of figure 1;
Figures 3-7 are enlarged views of the die and of the injection head of figure 1, wherein the filling phases of the die of figure 2 are shown;
Figure 8 is a schematic view of a different configuration of the apparatus wherein a second group of the invention phases can be realised;
Figures 9 and 10 are enlarged schematic views of the die after it has been filled and free, ready for the cooling phase and then during the cooling phase;
Figures 11-13 are views which show the die and the container during the transfer phases of the pastel stick from the die to the container;
Figures 14-17 are views which show the container during the following - in some cases optional - treatment phases; and
Figures 18-20 are views which show the final assembly phases of the whole container.
Referring first to Figure 1, it is described the apparatus to realise, according to the invention, a first group of phases of the process to fill a container for cosmetic products, in particular a pencil.
In the example, an apparatus 10 comprises a heating tank, which is shown in 11 and which comprises a sealed cell 12 with a controlled nitrogen atmosphere. The material placed in this tank 11 into the sealed cell 12 is fed through a gear pump 13 to an insulated feeding duct 14 under a defined pressure P1.
The duct 14 is connected to an injection head 15 provided with an obturator 16, for instance of the electromagnetic type.
A die 17 is placed right below said injection head 15 wherein a pastel or stick 28 for a pencil container, which will be herein described.
The die 17, better shown in figure 2, is formed by an outer structure or mold 18 wherein a mobile ejector 21 with an enlarged head 22 is placed inside a hole housing 19 and 20, having various shapes.
The mobile ejector 21 has the same diameter of the cosmetic product to be realised and slides along a first portion 20 of the hole housing, which defines a variable volume chamber. The chamber 20 has a variable volume which goes from zero or almost zero to the final value since said chamber is provided with a mobile wall subjected to a predefined counter-pressure, which is applied on the upper end 21a of the mobile ejector 21. This mobile end or wall 21a can be shaped.
The wall 21a can be moved between a first position, wherein said wall defines, inside the chamber 20, a volume almost equal to zero, and a second position, wherein said wall defines a volume equal to the final quantity of the filling product.
The enlarged head 22 slides instead along a second portion 19 of the hole housing.
The movement is driven and controlled by a cylinder 23 which applies a defined counter-pressure. A stem 24 of the cylinder 23 abuts against the enlarged head 22 thus entering into the portion 19 of the hole housing of the die 17. The cylinder 23 is provided with a numeric axis to control the length of the product while it is being manufactured. The pressures P1 and P2 are adjusted in function of the chemical and physical characteristics of the product to be obtained.
The apparatus of figure 1 works as follows in order to realise the process of the invention.
The mobile ejector 21 is brought to its maximum lifted position to fill the first portion 20 of the hole housing and said ejector is held in said position by the fully extended stem 24 (figure 3).
The die 17 is locked in said position through the same extended stem 24 and the injection head 15 gets closer to the upper inlet of the die 17.
Then, the obturator 16 of the injection head 15 is lifted in the direction of arrow 25 and the connection with the tank 11 (figure 4) is opened so that a hot liquid product, as the pastel, is fed through the duct 14 along the direction of arrow 25 under a pressure P1. Therefore, the injection phase of the liquid pastel starts.
It should be noted that during this phase the variable volume chamber 20 is at the zero or almost zero volume value, without any air contained inside said chamber. In this way, during the filling operation of said chamber, there is no need to let the air out and there is no formation of bubbles and of inclusions in the products which are being formed.
Figure 5 shows how, through a controlled feeding under pressure and counter-pressure, the filling of the upper portion 20 of the die is realised simultaneously with the withdrawal of the mobile ejector 21 and with the lowering of the stem 24 under counter-pressure. In this way, a controlled backward movement of the mobile wall 21a is realised.
In a following phase shown in figure 6, the filling has been completed when the stem 24 is almost out from the die 17 and the mobile ejector 21 is at the end of the first portion 20 of the hole housing of the die 17.
During these phases, it has taken place the continuous control of the length of the pastel, which is being made, by means of the numerical axis provided in the cylinder 23. The injection pressure P1 and the counter-pressure P2 have also been held at the respective values.
Then, the obturator 16 of the injection head 15 is lowered and the injection head is lifted along the direction of arrow 27 thus blocking the injection of the product. Then, the counter-pressure stem 24 is further lowered and the pastel 28 stays inside the die 17, as shown in figure 9, ready for the next cooling phase shown in figure 10.
In this phase, the cooling of the die 17 and of the pastel 28 injected by external means, shown in 29, is realised.
Figure 8 shows, through a schematic view, a different configuration of the apparatus wherein a second group of the invention process phases can be realised.
The die 17 is aligned with a lower second cylinder 30 provided with a pulling out stem 31.
A support element 32, for a container or a stick 33 of the pastel 28, is positioned above the die 17 and is aligned therewith.
The stem 31 is put in action and the pastel 28 is pushed in order to be transferred into the cup 34 of the container 33 (Figures 11 and 12).
During this phase, the mobile wall 21a is moved from the second position, previously mentioned, to the first position, mentioned as well.
The product 28, i.e. the pastel, which has been held and cooled in the chamber 20 of the die 17, is transferred into the cup 34 of the final container 33 from the same side where the chamber 20 is fed by the filling product.
Figure 13 shows the phase wherein, once the transfer of the pastel 28 has been finished, the stem 31 is in its withdrawn position and the support element 32 of the container 33 is driven so as to leave and go away from the die 17 below.
At this point, the die is ready to be brought back to the first apparatus to go again through the first above mentioned phase.
Figure 14 shows the container correctly filled with the corresponding pastel 28.
Figure 15 shows how, through the rotation of part of the container along the direction of arrow 35, the pastel 28 can be pulled out from said container.
This operation ends when the position of figure 16 is reached, wherein the pastel 28 can be subjected to various kinds of additional finishing treatment.
For instance, a flashing, a lacquering, a check or other operations to enhance the quality of the product can be performed. Then, the pastel is rotated in the direction opposite the arrow 35, i.e. in the direction of arrow 35 in figure 17, in order to have the pastel 28 return into the container 33.
Therefore, only the positioning of a cap 36 remains to be done, as shown in figure 18, to obtain a finished container shown in section in figure 19 and shown in a side view in figure 20.
In such a way the mechanical filling process of a container for cosmetic products, in this case of a pencil, has been completed, according to the present invention.
It should be noted that the process of the invention realises simultaneously a casting and a certain level of compactness. This is achieved thanks to the injection pressure and to the counter-pressure on the mobile ejector.
A product, with a consistency adjusted according to need in function of its chemical and physical characteristics, and free from defects, will be obtained.
The inner air is eliminated because the injection operation starts in a chamber having a volume equal to zero or almost zero since the volume wherein the product is injected has already been filled by the mobile ejector.
Further, there is no shrinkage in the product and an optimum aesthetic result is achieved.
This is evident from the above description referred to the figures.
It is therefore achieved the purpose mentioned in the description preamble.
Naturally, the embodiments of the process and of the apparatus can differ from the ones shown as a non limiting example in the drawings.
The protection of the invention is therefore defined by the attached claims.

Claims

Mechanical filling process of a container for cosmetic products, wherein:

during a first phase, a doughy, hot cosmetic product is fed, under pressure (P1), into a chamber (20) which has a volume variable between zero and the final value, the chamber (20) is also provided with a mobile wall (21a), and

during a second phase, the product, which has been fed into said chamber (20), is cooled;

the process is characterised in that:

the chamber (20), fed by the filling product, is the chamber of a forming die (17);

the mobile wall (21a) of the chamber (20) is subjected to a predefined counter-pressure (P2) during the first phase, and

during a third phase, the product (28), which has been held and cooled into said chamber (20) of said die (17), is transferred into the cup (34) of a final container (33).
Process as claimed in claim 1, characterised by maintaining said product feeding pressure (P1) and said predefined counter-pressure (P2) during the whole filling phase.
A process as claimed in claim 1, characterised by moving back, in a controlled manner, said mobile wall (21a), subjected to a predefined counter-pressure (P2), by means of a cylinder (23, 24).
Process as claimed in claim 1, characterised by realising the movement of said product (28), which has been held and cooled in said chamber (20) of said die (17), up into said cup (34) of said final container (33) by means of a cylinder (30, 31).
Process as claimed in claim 1, characterised by feeding said product into said die (17) through an injection head (15), said product having been placed in a heating tank (11), which has a sealed cell (12) with a controlled nitrogen atmosphere and a pump (13).
Process as claimed in claim 1, characterised by pulling out said product (28) placed into said cup (34) of said final container (33) in order to have said product subjected to an additional finishing treatment.
Process as claimed in claim 1, characterised in that the wall (21a) can be moved between a first position, wherein said wall defines a volume equal almost to zero inside the chamber (20), and a second position, wherein said wall defines a volume corresponding to the final quantity of the filling product.
Process as claimed in claim 7, characterised in that, during the third phase, the mobile wall (21a) goes from the second to the first position.
Process as claimed in claim 1, characterised in that the product (28), which has been held and cooled in said chamber (20) of said die (17), is transferred into the cup (34) of the final container (33) from the same side where the chamber (20) is fed by the filling product.
Mechanical filling apparatus (10) characterised by comprising a heating tank (11) for a cosmetic product, said tank comprises a sealed cell (12) with a controlled nitrogen atmosphere, whereto a gear pump (13) is associated in order to feed the cosmetic product placed inside said tank (11) into the sealed cell and then to an insulated feeding duct (14) at a defined pressure P1 towards an injection head (15) provided with an obturator (16),a die (17) is placed right below said injection head (15) wherein a molding shape (28) for said cosmetic product is obtained.
Apparatus as claimed in claim 10, characterised in that said die (17), is formed by an outer structure or mold (18) wherein a mobile ejector (21) with an enlarged head (22) is placed inside a hole housing (19, 20), having various shapes, said enlarged head (22) slides along a second portion (19) of said housing and its movement is driven and controlled by a lower cylinder (23) which applies a defined counter-pressure.
Apparatus as claimed in claim 10, characterised in that said mobile ejector (21) has the sane diameter of the cosmetic product to be realised and slides along a first portion (20) of said housing, thus defining a variable volume chanter.
Apparatus as claimed in claim 10, characterised by providing a further apparatus, associated thereto, for filling containers with the cosmetic product realised by the first filling apparatus.
Apparatus as claimed in claim 13, characterised in that said further apparatus for filling containers of the cosmetic product comprises a second lower cylinder (30), aligned below said die (17), wherein said second cylinder (30) is provided with a pull put stem (31), while above said die (17) a support element (32) for a container (33) of the shaped cosmetic product (28) is aligned thereto.
Cosmetic product container obtained through a process and/or an apparatus according to the preceding claims.