EP0354137A1 - Process for making a pocket dispenser, parts thereof and dispensers - Google Patents

Abstract

The subject of the invention is a method of manufacturing and packaging a bag dispenser comprising a box surmounted by a dome (2) a waterproof flexible bag (4) fixed in this box and dispensing means connected in a sealed way. to said dome (2) and to said pocket (4) characterized in that, before any other assembly and packaging operation, a plastic dome (2) is produced by molding comprising an internal tube (5) allowing its fixing watertight on the upper end of a skirt (4) forming the blank of the pocket, then this fixing is carried out, thus obtaining a preassembled part (dome + skirt) (1), the dome (2) further comprising fixing portions (6,7) respectively on the upper end of the housing and on the distribution means. The invention also relates to the subassemblies and the pocket dispensers obtained. The invention applies in the pharmaceutical, cosmetological, hygienic and food fields.

Description

The invention relates to a pocket dispenser and its manufacturing and packaging method. Such a pocket dispenser is used for cosmetic, pharmaceutical, hygienic or food products.

The document FR-A-2 310 827, corresponding to patent US-A-4,045,860, describes an aerosol container with two chambers or "with pocket" in which, so as to obtain a perfect seal at the level of the fixing of the pocket on the outer container or case, an annular seal is put in place between the rolled edge of the dome of the case and the collar of the pocket, this collar being released from the case by an extractor then this extractor itself is released from the pocket. The fixing cup of the dispensing valve is then put in place on the upper edge of the housing and the peripheral flange of this cup is crimped around the rolled edge, the annular seal being thereby tightened between this rolled edge and the cup. the pocket on the one hand and the flange of the valve fixing cup on the other hand. The assembly operations ending with this crimping are thus delicate and relatively complex.

The Applicant has sought to develop a manufacturing process in which the assembly operations are simplified, particularly those which follow the manufacture of the housing.

EXPOSURE OF THE PROBLEM

The subject of the invention is a method of manufacturing and packaging a bag dispenser comprising a box surmounted by a dome, a flexible waterproof bag fixed inside this box and distribution means connected in a sealed manner to said dome and to said pocket. According to the invention, before any other assembly and packaging operation, a plastic dome is produced by molding comprising an internal tube allowing its tight fixing on the upper end of a skirt forming the blank of the pocket, then this fixing is carried out, thus obtaining a preassembled part (dome + skirt), the dome further comprising fixing portions respectively on the upper end of the housing and on the distribution means. The pocket blank skirt is thus tightly fixed to a dome which will connect the housing to the distribution means, instead of being fixed to the housing as in the prior art.

In the present description, the vertical direction is by convention that of the longitudinal axis of the housing and of the skirt or pocket, and the top of the dispenser or of its constituent parts corresponds to the end of this dispenser carrying the dispensing means.

The pre-assembled part (dome + skirt) has significant advantages:
- the shaping and assembly operations are facilitated;
- The problem of sealing between pocket and upper edge of the case is simplified;
- the part (dome + skirt) can be tightly attached either first to the upper end of the housing, or first to the distribution means, which allows the bag to be filled from above or from below ;
- The axis of the upper opening of the dome, and therefore the direction of distribution of the product, can be oriented in various ways, by simply changing the geometry of the dome;
- the manufacturing process can be adapted to various types of distributors:
. having a metal case, with a distribution valve, and a propellant between pocket and case;
. or having a metal casing or a casing made of plastic or metallo-plastic material, with a distribution pump with little or no air intake, the bag then being subjected to atmospheric pressure;
- As we will see, the methods of fixing the part (dome + skirt) are varied and industrially simple and reliable, their choice allows to carry out the manufacturing with various types of equipment.

The interior dome tubing is tightly sealed to the upper end of the pocket blank skirt either by means of a clamp or elastic tightening the skirt around the tubing, possibly in an annular groove in this tubing, solution valid for small series, or preferably for large series by molding during molding of the dome, or by gluing the end of the skirt around said tubing.

In the case of direct production by molding of the part (dome + skirt), a portion of the tubular skirt is threaded around a punch so that its upper end exceeds a chosen length of this punch. This skirt is then included between this punch and the die tools which define with this protruding end, with tools inside the punch and with die bottom tools, an annular interval supplied with plastic material, typically by at least two injection channels. lateral or oblique. The annular molding interval thus defined has, in cross section, the profile of the dome part to be produced, and makes it possible to obtain the desired part (dome + skirt) on demolding. The skirt is connected to the dome part of this part by an inner tube which comes to adapt to the mounting in the neck of the housing.
The upper end of the skirt embedded in this tubing by molding can thus be: either flush with the interior surface of the tubing, or in the thickness of this tubing and preferably closer to the outer surface of the tubing inner of the dome than its inner surface, or, even more advantageously for overmolding, on the outer surface of said tube. Experience has also shown that the sheath, which is usually very thin, for example 0.2 to 0.3 mm thick, tends, when used as a pocket, to close at the end of emptying by twisting effect, and this when the upper end of this pocket was welded to the tubing of the dome for only 3 to 4 mm. This drawback is avoided and a more complete emptying of the bag is obtained at the end of dispensing of the product by taking a higher inner tubing of the dome and by molding so that the end of the bag is included in the thickness of the dome, that is to say typically of its internal tubing, or linked to this tubing, on 5 to 20 mm in height, at best 8 to 15 mm.

In the case of gluing the upper end of the waterproof skirt around the inner tubing of the dome, it is preferable to surface oxidize one of the two surfaces to be bonded beforehand, typically by flaming or by Corona effect. When the inner surface of the skirt is made of PE, it must therefore be surface oxidized to obtain good adhesion of the adhesive. Care must be taken to ensure that the glue which is then applied, usually to the tubing, is not completely scraped off by the introduction of the skirt. A first solution is to leave a slight clearance between the skirt and the tubing, the inside diameter of the skirt being approximately 0.2 to 0.3 mm greater than the outside diameter of the tubing, so as to leave a film of adhesive. .
A second, much better solution is to have, preferably with a slight tightening of the skirt on the tubing, one or more annular recessed zones for glue retention on the surface to be glued on the dome tubing, zones of depth less than 0.15 mm to facilitate demolding of the dome.
When there are several annular zones, at the optimum height or width between 0.5 and 2.5 mm and depth between 0.04 and 0.1 mm, they are advantageously connected to each other by bridges or hollow passages of equal or similar depth so as to improve the distribution of the adhesive when belted by the skirt. These annular zones can furthermore, to allow a more convenient and safer bonding, be preceded by an end portion carrying a flexible annular lip inclined upwards serving as a glue reserve, the bottom of this reserve being connected to the closest hollow annular zone, that is to say the first hollow annular zone starting from the end of the tube, by hollow bridges. The introduction of the skirt around the tubing then tightens this flexible lip by expelling glue towards the hollow annular zone or zones, this glue spreading through said hollow bridges.

The bonding tests which have been carried out have shown that cyanoacrylate adhesives are particularly suitable for industrial manufacture, the annular dome preferably being for its rigidity, made of polyamide, polyacetal or polycarbonate, and the skirt being at least on the surface. inner PE (polyethylene).
Once the piece (dome + skirt) is made, the fabrica sequences tion can vary significantly, with operations being split between the packaging manufacturer and the conditioner to the best of their ability.

• a) on ferme l'extrémité inférieure de la jupe de la pièce (dôme + jupe), cette jupe devenant une poche;
• b) on introduit cette poche de la pièce précédente devenue (dôme + poche) dans le boîtier;
• c) on fixe de façon étanche cette pièce par sa partie dôme à l'extré­mité supérieure du boîtier; puis chez le conditionneur:
• d) on effectue le remplissage du produit à distribuer par le haut de la poche;
• e) on fixe de façon étanche au haut de la partie dôme les moyens de distribution comprenant soit une valve, soit une pompe à reprise d'air faible ou nulle;
• f) lorsque les moyens de distribution comprennent une valve, on introduit un gaz sous pression entre la poche et le boîtier.

According to a first production range, the other assembly and packaging operations are carried out in the following order:

• a) the lower end of the skirt of the part is closed (dome + skirt), this skirt becoming a pocket;
• b) this pocket of the previous part which has become (dome + pocket) is introduced into the housing;
• c) this part is tightly fixed by its dome part to the upper end of the housing; then at the conditioner:
• d) the product to be dispensed is filled from the top of the bag;
• e) the distribution means comprising a valve or a low or no return air pump are fixed in a sealed manner at the top of the dome part;
• f) when the dispensing means comprise a valve, a pressurized gas is introduced between the pocket and the housing.

• a₁) on fixe de façon étanche au dôme de la pièce (dôme + jupe) les moyens de distribution comprenant soit une valve, soit une pompe à reprise d'air faible ou nulle;
• b₁) on retourne l'ensemble obtenu et on remplit la jupe, obturée par le dôme et par lesdits moyens de distribution, du produit à distribuer, par l'extrémité inférieure de cette jupe située en posi­tion haute;
• c₁) on ferme ladite extrémité de la jupe, qui devient une poche;
• d₁) on introduit la poche remplie du nouvel ensemble obtenu (dôme + poche + moyens de distribution) dans le boîtier;
• e₁) on fixe de façon étanche ce nouvel ensemble par sa partie dôme à l'extrémité supérieure du boîtier;
• f₁) lorsque les moyens de distribution comprennent une valve, on introduit un gaz sous pression entre la poche et le boîtier.

According to a second manufacturing range in which packaging and assembly are integrated, the other assembly and packaging operations are carried out in the following order:

• a₁) is fixed sealingly to the dome of the room (dome + skirt) the distribution means comprising either a valve or a low or no return air pump;
• b₁) the assembly obtained is turned over and the skirt, closed by the dome and by said distribution means, is filled with the product to be distributed, by the lower end of this skirt located in the high position;
• c₁) closing said end of the skirt, which becomes a pocket;
• d₁) the pocket filled with the new assembly obtained (dome + pocket + dispensing means) is introduced into the housing;
• e₁) this new assembly is tightly fixed by its dome part at the upper end of the housing;
• f₁) when the dispensing means comprise a valve, a pressurized gas is introduced between the pocket and the housing.

In the case where the distribution means then comprise a low or no return air pump provided with an annular fixing flange at least externally made of plastic, it is advantageous in series production to carry out the fixing of this pump to the dome - that is to say the operation (a₁) - at the same time as the fixing of the skirt or dome by molding. The direct molding process already described for the part (dome + skirt) is modified in that the annular molding cavity defining the dome comprises the periphery of the annular rim of the pump. The tools containing the pump and protecting it from overheating of the molding are a lower tool with central cavity surmounted by a flange supporting said flange in leaktight fashion, and a bottom tool of matrix covering the pump and resting on the flange by completing the seal against the molten plastic. The connection obtained between the dome and the rim of the pump is either a weld if the plastics concerned are of the same nature, or a bonding with intimate adhesion, without reflow, ensuring however, as has been verified, a good seal when the materials Plastics are dissimilar, for example polypropylene for the pump ring and PE-HD for the dome. To improve the strength of this fixing and the security of the corresponding seal, it is then advisable to provide the annular rim in its part included by molding at least one fine rib or circular groove. Once the assembly (dome + skirt + pump) thus obtained, we continue with operations (b₁) to (e₁).

• a₂) on fixe de façon étanche au dôme de la pièce (dôme + jupe) les moyens de distribution comprenant soit une valve, soit une pompe à reprise d'air faible ou nulle;
• b₂) on introduit la jupe de l'ensemble obtenu (jupe + dôme + moyens de distribution) dans le corps du boîtier;;
• c₂) on fixe de façon étanche ledit ensemble par sa partie dôme à l'extrémité supérieure dudit corps de boîtier; puis chez le condition­ neur:
• d₂) on retourne l'ensemble complexe obtenu et on remplit la jupe, obturée par le dôme et lesdits moyens de distribution du produit à distribuer, par l'extrémité inférieure de cette jupe située en position haute;
• e₂) on ferme ladite extrémité de la jupe, qui devient une poche, et on rentre si nécessaire cette extrémité, dans le corps de boîtier;
• f₂) on sertit le fond métallique qui est percé d'un trou sur l'extré­mité inférieure ouverte du corps métallique;
• g₂) lorsque les moyens de distribution comprennent une valve, on introduit un gaz sous pression entre la poche et le boîtier et on bouche le trou du fond métallique.

According to a third manufacturing range and in the case where a metal case is used comprising a tubular body and a separate bottom, for example both made of tinplate or possibly aluminum, the other assembly and packaging operations are carried out in the '' following order:

• a₂) is fixed sealingly to the dome of the room (dome + skirt) the distribution means comprising either a valve or a low or no return air pump;
• b₂) the skirt of the assembly obtained (skirt + dome + distribution means) is introduced into the housing body;
• c₂) said assembly is fixed in leaktight manner by its dome portion to the upper end of said housing body; then at the condition neur:
• d₂) the complex assembly obtained is returned and the skirt is filled, closed by the dome and said means for dispensing the product to be dispensed, by the lower end of this skirt located in the high position;
• e₂) closing said end of the skirt, which becomes a pocket, and if necessary this end, into the housing body;
• f₂) crimping the metal bottom which is pierced with a hole on the open lower end of the metal body;
• g₂) when the dispensing means comprise a valve, a pressurized gas is introduced between the pocket and the housing and the hole in the metal bottom is plugged.

As in the second manufacturing range, in the case where the distribution means comprise a low or no return air pump carrying an annular fixing rim at least externally made of plastic, it is advantageous to first produce a dome plastic molded both on the skirt forming the blank of the pocket and around said pump fixing flange. After having thus produced an assembly (dome + skirt + pump), we continue with operations (b₂) and (c₂), then usually at the conditioner with the same operations (d₂) to (g₂).

We can go further in the case of pre-assembly by molding and directly make an assembly (dome + skirt + pump + metallic tubular body), which then replaces the elementary molding (dome + skirt) and operations (a₂) to c₂) .

The molding tools are then of the same type as those described for the variant of the second manufacturing range, with the following modifications:
there is a double concentric punch allowing the positioning of the skirt of the pocket and the skirt of the metallic tubular body and the release from the mold, and the annular molding cavity surrounds a rolled edge prepared at the upper end of the metallic tubular body , the connection of the dome being at this level produced by filling the inside and outside of this edge. This rolled or folded edge is not closed and can be much less tight than a rolled edge for crimping, which is an advantage of ease of manufacture and flexibility.

The complex assembly then obtained is then ready for the packaging operations (d₂) to (f₂).

In addition to the molding of sets of parts or "sub-assemblies of distributors" already described, various methods of fixing the part (dome + skirt) can be used and will be described with reference to the examples and the drawings which illustrate them. The method of closing the lower end to give a pocket is important to facilitate re-entry of the pocket into the case, it will also be explained.

The invention also relates to the pre-assembled part (dome + skirt) as well as the various assemblies or sub-assemblies produced.

EXAMPLES

• Figure 1 shows a preassembled part (dome + skirt) in axial section.
• FIG. 2 represents a distributor obtained from this part (dome + skirt), also in axial section.
• Figures 3 and 4 show the contours of two end closures of the skirt, in section perpendicular to the axis.
• Figures 5 to 7 show different sealed connection modes of the dome and the upper end of a metal case, in axial half-section.
• FIG. 8 represents a part (dome + skirt), the dome of which is provided on its reverse side with an insert forming a barrier for perfumes, in axial half-section.
• Figure 9 shows the assembly of a part (dome + skirt) and the upper end of a plastic housing, in axial half-section.
• FIG. 10 shows a dispenser with a metal case, the bottom of which is to be crimped, corresponding to the third manufacturing range described, in partial axial section.
• FIG. 11 represents an assembly of a part (dome + skirt) and of the upper end of a metal case, the skirt and the dome being assembled by molding, in axial section.
• FIG. 12 represents a part (dome + skirt) assembled by gluing, in axial section.
• FIG. 13 shows the internal tubing of a dome provided with means for distributing the adhesive, in axial half-section.
• Figure 14 shows a distributor obtained from the part (dome + skirt) of Figure 12, in axial section.
• FIG. 15 represents the outline of the triangular star weld of the pocket of the preceding dispenser, seen at the end.

EXAMPLE 1

The part (dome + skirt) of FIG. 1 comprises a dome 2 made of high density polyethylene (PE.HD) molded on the upper end portion 3 of a metalloplastic skirt 4 with an outside diameter of 35 mm and a thickness of 0, 28 mm comprising 5 layers, either from the outside to the inside:
- 1 layer of white PE.BD (added with titanium oxide powder) of thickness 90 µm;
- 1 layer of 30 µm EAA-based copolymer adhesive;
- 1 layer of aluminum 40 µm thick;
- 1 new layer of the same 30 µm adhesive;
- 1 inner layer of medium density PE, thickness 90 µm.

The upper end 3 of the skirt 4 has been trapped by molding in an inner tube 5 of the dome 2, with an outside diameter of 36.3 mm, over a height of 13 mm, its inner and outer layers therefore being partially recast. and welded and the plastic covering of the dome 2 being 0.8 mm on the outside and 1.5 mm on the inside.
This arrangement ensures at the top of the skirt closed in the pocket sufficient rigidity so that the opening of this pocket remains during the last product distributions.

The dome part 2 comprises on the outside of its internal tube 5 a semicircular groove 6, of radius 1.5 mm in axial section and of average diameter 42 mm, the outside diameter of the dome 2 being 45 mm.

The dome 2 comprises at its upper end an external bulge 7 of external diameter 20 mm allowing the crimping of a cup metallic valve or distribution pump.

EXAMPLE 2

The part (dome + skirt) 1 was used to manufacture a pocket dispenser 8 (FIG. 2) according to the method of the first manufacturing range. The lower end 9 of the skirt 4 has been closed by arc welding, this end being folded back into a lined semi-circular shape 10 as shown in the diagram in FIG. 4 and pinched to a height of 6 mm by welding. This arrangement gives a welded end 12 of the pocket 13 of curved shape but of the same diameter as the skirt 4 and presenting no difficulty of introduction into the housing 11. After welding, the weld 12 has been freed of approximately 2 mm. , thus eliminating its excess length from the non-welded outer end.

FIG. 3 represents, in the same way as FIG. 4, another so-called "bellows" folding mode 14 providing the same advantage of non-enlargement of the end of the pocket, the closure of the end then being carried out by gluing, or by welding, the latter being more delicate than in arc welding.

The housing 11 of the distributor 8 is made of aluminum with a thickness of the cylindrical body 0.35 mm and an opening or groove 15 with an internal diameter of 36.5 mm surmounted by a rolled edge 16 over approximately 150 ° of external radius 1.3 mm. The attachment of the dome 2 to the rolled edge 16, after the closure of the pocket 13 and its introduction into the housing 11 was made by surface oxidation of the circular groove 6 of the dome 2 (Corona treatment) and bonding with cyanoacrylic adhesive of this groove 6 fitted on the rolled edge 16 and held in abutment for a little more than 1 minute during the drying of the glue.
Other known methods for treating the surface of the plastic groove can be used, for example a flame treatment or with a shaped electrode (Corona effect).
The metal fixing cup 17 of a distribution means 18, here capped with a pusher-diffuser 19, has been crimped with a seal under the bulge 7 of the upper end of the dome 2. When this means 18 is a product outlet valve, the annular gap 20 between the housing 11 and the pocket 13 is filled with a pressurized gas and the tight plug 21 is then replaced. When the means 18 is a pump without air intake, there is no need for propellant gas and putting the outside of the bag 13 at atmospheric pressure is sufficient, which simplifies the packaging. In the present case, the plug 21 is removed, and the bottom 22 of the housing provided with any air passage orifice has only a protective role for the bag, not necessary for the operation of the distribution.

EXAMPLE 3

The attachment of the dome 2 of the prefabricated part (dome + skirt) 1 to the housing is typically done by the packaging manufacturer. Various methods can be used in mass production. The methods which relate to metal housings, typically aluminum or tinplate of thickness 0.2 mm to 0.6 mm, the distributors being as we have already seen pressurized or not, are commented below in relation with Figures 5 to 7.

FIG. 5 represents the fixing of a dome 2 provided with a skirt 4, of the same geometry as in the first two examples, on a housing 11 identical to the housing of FIG. 2, using an annular part of link 23 compatible both with the plastic of the dome 2 - here PE.HD - and the metal of the housing 11 - here aluminum. This molded part 23 0.2 mm thick is in complex containing the same polyolefin as that of the dome 2, that is to say of PE, and EAA; its outer edge is snapped onto the end of the rolled edge 16, and after the installation of the part 1, the dome 2 coming to be applied by its circular groove 6 on the connecting part 23, the welding is carried out by the 'one of the following methods: by high frequency induction, by rotation, or by ultrasound by modifying the shape of the dome for the support of the ultrasonic transducer.

In FIG. 6, it can be seen that the dome 2, put in place by its circular groove 6 on the rolled edge 16 of the housing 11, has a circular groove end 6 projecting about 1 mm beyond the end of the rolled edge 16, without obstructing the interior of this rolled edge 16. By annular injection of plastic material of the same nature as that of the dome, here of PE, the interior cavity of the rolled edge 16 is at least partially filled by partially melting the outer lip 24 of the dome bordering the end of the circular groove 6, this lip 24 having at this point 1 mm thick. A good quality sealed welded connection is obtained. In general, the end 24 of the dome 2 thus secured by the molding must come in the vicinity of the end of the rolled edge, either less than 0.5 mm before this end or a little further leaving at least 1 mm of passage inward of the rolled edge 16.

The fixing method of FIG. 7 uses an annular piece of plastic shape 25 of the same kind as that of the dome 2, the top of which is not shown, this piece 25 being placed on the end of the constricted housing 26 before rolling its end edge. This part 25, here in PE like the dome 2, has a base 27 resting on the shoulder 26 of the housing 11, an upper portion 28 which will be crimped as shown by rolling the upper end edge of the housing, as well as one or more surfaces, here the two surfaces 29 and 30, coming into contact with the outer skirt 31 of the dome 2. The positioning of the shaped part 25, the rolled edge 16 and the dome 2 being made, the waterproof fixing is carried out by welding by rotation of the annular surfaces 29 and 30 against the annular portion 31 of the dome 2. The fixing can also be made by welding by HF induction or by ultrasound.

EXAMPLE 4

The external geometry of the preassembled part 101 (FIG. 8) is the same as that of the part 1, but the reverse surface 32 of its dome 102 was provided during the molding of this dome 102 on the skirt 4 with an annular washer. 33 with barrier effect. This washer 33 is welded to the dome 102 by a large face 34 and retained at its base by a small annular bead of plastic material 35. It generally has surface layers of polyolefin compatible with the polyolefin of the dome and an intermediate layer of A1 or barrier plastic. The metalloplastic complex 0.28 mm thick in the first example is used here for the washer 33.

EXAMPLE 5

The housing 110 of FIG. 9 is made of plastic, here HDPE 0.6 mm thick in its cylindrical part. This molded housing has at its upper end 116 a tube 111 of axial section rectangular which fits tightly between the inner tube 115 and an annular groove 114 of the dome 112, the tube 111 applying by its horizontal end against the bottom of the groove 114. The fixing is preferably made by welding by rotation , it can also be made by gluing. The horizontal annular surface 113 and the end of the outer lip 117 of the dome 102 can also intervene in this fixing.

EXAMPLE 6

FIG. 10 illustrates the process of the third manufacturing range. The preassembled part 1 is the same as in the first two examples, and the fixing of this part 1 to the upper end of the housing 211 with separate bottom 212, tin box with external diameter 47 mm and thickness 0.3 mm is made like that of the second example, the skirt 4 not however being closed. A cover 213 is adapted to protect the distribution means 18 and 19, and the filling takes place in the inverted position by the open end of the skirt 4 projecting from the body of the housing 211. The end of the skirt 4 is then closed, typically by one of the methods already described in the second example, the closed end is freed and returned to the body 211, then the bottom 212 is crimped. The dispenser is then pressurized if necessary as already described.

EXAMPLE 7

FIG. 11 shows a dome 302 made of PE.HD molded onto the upper end portion 3 of a metalloplastic skirt 4 identical to the skirt 4 of Example 1. In the present case, the internal tubing 325 of the dome 302 is molded on the inside of the end 3 of the skirt 4, the tubing 325 being reinforced by a thickening of its upper part which constitutes part of the periphery of its semicircular annular groove 6 for fixing to the housing 11.
The flared arrangement of the end 3 around the tube 325 results from the direction of injection of the HDPE, this injection pressing this end 3 against the annular molding tool.
The dome 302 is fixed to the rolled edge of the housing 11 by gluing with cyanoacrylate glue, in the same way as in Example 2. The bulged upper part 70 of the dome 302 allows the distribution means to be fixed by expansion.

EXAMPLE 8

FIG. 12 represents a dome 312 made of polyamide PA 12, the internal tubing 335 of external diameter 34.3 mm is glued over 12 mm in height inside a metalloplastic skirt 4 identical to the previous skirts. This arrangement was the subject of a set of bonding tests, concerning domes of different materials:
. PA 12 (= Rilsan Ⓡ)
. PA 6 (= Nylon Ⓡ)
. PE. HD
. Linear PE
these domes being glued to the rolled edges of the upper end of aluminum boxes, with families of glue:
. "Rhodorseal 5552" silicone glue (Ⓡ)
. three cyanoacrylate adhesives:
N ° 406 Loctite (Ⓡ)
N ° 202 Cyanolit (Ⓡ)
N ° 208 Cyanolit (Ⓡ)

The observations made can be summarized as follows: the plastic surfaces must preferably be prepared by surface oxidation such as flame or Corona effect, and the aluminum surfaces must preferably be previously varnished, these adhesives not giving satisfactory adhesion to bare aluminum. Silicone glue requires pressing times of 1 to 2 min and ambient drying times greater than 24 h. The three cyanoacrylate adhesives give similar results: the pressing times can be limited to 5 to 10 seconds, and the parts can be handled after 30 seconds to 1 minute at room temperature. These cyanoacrylate adhesives are therefore much preferable for industrial application.

During these bonding tests, it was noted that the well-centered introduction of the skirt 4 around the tubing 335 of the dome was delicate and that there were sometimes lack of bonding corresponding to excessive scraping of the adhesive by the end of the skirt 4. After several tests, a dome 322 made of PE.HD shown in FIG. 13 is then produced, the tubing 345 of which comprises, starting from its end lower: a flexible lip 346 delimiting with the circular cylindrical outer surface 347 of the tubing 345 an annular reserve 348 of height 2.5 mm, then 5 mm above the lower end a portion of frustoconical outer surface 349 of 1/2 cone angle between 1 and 2); this portion 349 comprising 2 hollow annular zones 350 and 351 of depth 0.06 to 0.08 mm, these zones of unitary heights 2 mm being connected to each other as well as to the cylindrical portion 347 by a plurality of hollow bridges of unit width 4 mm. The frustoconical outer surface 349 extends to the lower edge 326 of the dome 322 corresponding to the open end of the groove 6 for attachment to the housing, this edge 326 serves as a stop and adjusts the threading of the skirt 4 around the tubing 14 mm high. Taking into account the glue reserve system 348, 350 and 351, the skirt 4 is slightly tightened on the tubing 345, and we have here, for the inner skirt diameter of 34.45 mm with one end of the inlet tubing 352 progressive: a diameter of the cylindrical outer surface 347 of 34.1 mm, a flexible lip 346 of thickness 0.15 to 0.2 mm at its root and a frustoconical outer surface 349 ending with a diameter of 34.5 mm. The tests with cyanoacrylate adhesive deposited in advance in the annular reserve 348 gave reproducible results and, according to the detachment tests of the skirt 4, a reliable seal is obtained at each of the hollow zones 350 and 351.

EXAMPLE 9

We used a part (dome + skirt) 312 and 4 (Figure 14) pre-assembled by gluing (Example 8 and Figure 12) to manufacture a bag dispenser 80 according to the method of the first manufacturing range. Compared to Example 2, we have the following additional differences:
the outer lower edge 327 of the dome 312, bordering its annular groove 6 for fixing by gluing to the rolled edge 16 of the aluminum housing 11 has a small overhanging edge 328 allowing the latching of a protective cover, not shown, and a small skirt or extension 329 masking the fixing of the dome 312 on the rolled edge 16;
- As shown in Figure 15, we welded in a triangle, or more exactly in a triangular star or three substantially equal branches, the lower end90 of the skirt 4 before introduction of this skirt 4 in the housing 11. This welding was done by means of 3 insulating clamps and an HF induction loop, method with which a sufficient creep of the PE is obtained to obtain the seal in the center of the star. Ultrasound can also be used. This arrangement in three flexible folds, gradually catching up with the circular cylindrical shape of the top of the skirt 4, allows a particularly convenient introduction of the pocket obtained in the dispenser housing. Four or more folds are also possible.

BENEFITS

Important advantages have already been indicated at the beginning of the description of the invention.

The tests carried out made it possible to highlight another advantage, particularly surprising and interesting from an economic point of view. The use of the plastic dome makes it possible to reduce the size of the constriction of the upper end of the case in the case of a metal case. We can then significantly reduce the thickness of the cylindrical part of the housing, the only requirement for resistance to internal pressure allowing the thickness of the side wall to be less than the same requirement associated with the resistance requirement of the highly constricted dome. This reduction in wall thickness is typically 20 to 35% relative.

APPLICATIONS

The application of the manufacturing process of the invention and of the corresponding bag dispensers extends to the distribution of aerosol products, liquids and creams or gels, in the pharmaceutical, cosmetological, hygienic and food fields.

Claims (37)

1. A method of manufacturing and packaging a bag dispenser (8; 80), said dispenser (8; 80) comprising a housing (11; 211) surmounted by a dome (2; 102,112; 302; 312; 322 )), a flexible waterproof pocket (13) fixed inside this housing (1) and distribution means (18,19) connected in a sealed manner to said dome (2; 102; 112; 302; 312; 322) and to said pocket (13), characterized in that, before any other assembly and packaging operation, a plastic dome (2; 102) comprising an internal tube (5; 115; 325; 335) is produced by molding ; 345) allowing its tight fixing on the upper end (3) of a skirt (4) forming the blank of the pocket (13), then this fixing is carried out, thus obtaining a preassembled part (dome + skirt) ( 1; 101; 312 and 4), the dome (2; 102; 302; 312; 322) further comprising fixing portions (6; 114) (7; 70) respectively on the upper end (16; 116) of the housing (11; 211) and at the mo distribution yen (18.19). 2. Method according to claim 1, in which said inner tube (5; 115) of the dome (2; 102) is fixed to the upper end (3) of said skirt (4) by molding, during hard molding of the dome ( 2: 102). 3. Method according to claim 2, wherein one carries out the molding of the internal tube (5; 115) of the dome (2) on the skirt (4) forming the blank of the pocket (13) so that the end upper (3) of this skirt (4) is included in the thickness of said tubing (5; 115) and closer to the outer surface of said tubing (5; 115) than to its inner surface. 4. The method of claim 2 wherein the inner tube (325) of the dome (2) is overmolded on the inside of said skirt (4). 5. Method according to any one of claims 3 or 4, wherein the upper end (3) of said skirt (4) is included in the thickness of said tubing (5; 115) or linked to this tubing (325 ) over a height of 8 to 15 mm, so as to allow better emptying of the bag (13) during use. 6. The method of claim 1, wherein said inner tube (335; 345) of the dome (312; 322) is fixed on the upper end (3) of said skirt (4) by gluing said upper end (3) around said tubing (335; 345). 7. The method of claim 6, wherein said inner tube is fixed (335; 345) on said upper end (3) of said skirt (4) over a height between 5 and 20 mm. 8. The method of claim 6, wherein at least one of the two surfaces to be bonded is oxidized by flame or by Corona effect. 9. The method of claim 8, wherein the surface to be bonded of said tubing (345) of the dome (322) comprises at least one annular recess area for glue retention (350,351) of depth less than 0.15 mm. 10. The method as claimed in claim 9, in which said surface to be glued to said tubing (345) comprises at least 2 annular hollow zones (350,351) connected to each other by hollow bridges, said zones (350,351) each having a height included. between 0.5 and 2.5 mm and a depth between 0.04 and 0.1 mm. 11. The method as claimed in any one of claims 9 or 10, in which the recess (s) annular zone (s) (350,351) are preceded by an end portion of said tube (345) carrying a lip flexible annular inclined upwards (346) serving as a glue reserve, the bottom of this reserve (348) being connected to the nearest hollow annular zone (350) by hollow bridges, the introduction of said skirt ( 4) around said tubing (345) causing the tightening of said flexible lip (346) and an expulsion of the adhesive towards the said annular zone (s) (350,351) by hollow bridges. 12. Method according to any one of claims 8 to 11, in which the bonding is carried out with a cyanoacrylate adhesive, the annular dome (312,322) being made of polyamide, of polycarbonate or in polyacetal, and the interior of said skirt (4) being in PE. 13. Method according to any one of claims 1 to 12, in which the other assembly and packaging operations are carried out in the following order: a) closing the lower end (9; 90) of the skirt (4) of the part (dome + skirt) (1.110; 312 and 4) this skirt (4) becoming a pocket (13); b) this pocket (13) of the previous part which has become (dome + skirt) (1) is introduced into the housing (11; 211); c) this part (1; 101) is tightly fixed by its dome part (2; 312) to the upper end (16; 116) of the housing (11; 201); d) the product to be dispensed is filled from the top of the bag (13); e) the dispensing means (18; 19) comprising either a valve (18) or a pump (18) with low air intake are tightly fixed to the top (7) of the dome part (2; 102) or zero; f) when the dispensing means comprise a valve (18), a pressurized gas is introduced between the pocket (13) and the housing (11; 211). 14. The method as claimed in any one of claims 1 to 12, in which the other assembly and packaging operations are carried out in the following order: a₁) sealingly fixed to the dome (2; 102) of the part (dome + skirt) (1; 101) the distribution means (18; 19) comprising either a valve or a low air intake pump or zero; b₁) the assembly obtained (1 and 18.19) is turned over and the skirt (4) closed by the dome (2; 102) and by said distribution means (18; 19) of the product to be distributed is filled, by the 'lower end (9) of this skirt (4) located in the high position; c₁) closing said end (9) of the skirt, which becomes a pocket (13); d₁) the pocket (13) filled with the new assembly obtained (dome + pocket + distribution means) (1 and 18; 19) is introduced into the housing (11); e₁) this new assembly (1 and 18; 19) is tightly fixed by its dome part (2; 102) to the upper end (16; 116) of the housing (11; 211); f₁) when the distribution means (18; 19) comprise a valve (18), gas under pressure is introduced between the pocket (13) and the housing (11; 211 and 212). 15. The method of claim 14, in the case where the manufacturing means comprise a low or no return air pump carrying an annular rim for fixing at least externally made of plastic, in which a dome is first made plastic material (2) molded both on the skirt (4) forming the blank of the pocket (13) and around said pump fixing flange, then in which the operations (b₁) to (e₁) are executed. 16. Method according to any one of claims 1 to 12, in the case where a metal case is used comprising a tubular body (211) and a separate bottom (212), and in which the other assembly operations are carried out and packaging in the following order: a₂) sealingly fixed to the dome (2) of the part (dome + skirt) (1) the distribution means (18; 19) comprising either a valve or a low or no return air pump; b₂) the skirt (4) of the assembly obtained (skirt + dome + distribution means) is introduced into the body (211) of the housing; c₂) said assembly is fixed in leaktight manner by its dome part (2) to the upper end (6) of said housing body (211); d₂) the complex assembly obtained is returned and the skirt (4) closed by the dome (2) and said means (18; 19) for distributing (9) this skirt (4) located in the high position is filled; e₂) closing said end of the skirt (4), which becomes a pocket (13), and if necessary this end (9) is inserted into the housing body (211); f₂) crimping the metal bottom (212) which is pierced with a hole on the open lower end of the metal body (211); g₂) when the dispensing means comprise a valve, a pressurized gas is introduced between the pocket (13) and the housing (211) and the hole in the metal bottom (212) is plugged. 17. Method according to claim 16 in the case where the distribution means (18; 19) comprise a pump (18) with little or no air intake carrying an annular fixing flange at least externally made of plastic, in which first produced a dome (2) made of plastic molded both on the skirt (4) forming the blank of the pocket (13) and around said pump fixing flange (18) then in which the operations (b₂) to (f₂). 18. Method according to claim 16, in the case where the distribution means (18; 19) comprise a low or no return air pump carrying an annular fixing rim at least externally made of plastic, and where the end upper part of the housing body (11) carries a rolled edge (16), process in which a dome (2) is first made of plastic molded at the same time on the skirt (4) forming the blank of the pocket ( 13), on said upper end of the housing (16) and around said pump fixing flange, then in which the operations (d₂) to (f₂) are carried out. 19. Method according to any one of claims 13 to 18, in which the lower end (9) of the skirt (4) is closed by folding in bellows (14) and gluing or welding. 20. Method according to any one of claims 13 to 18, in which the lower end (9) of the skirt (4) is closed by arc welding (10). 21. Method according to one of claims 13 to 18, in which the lower end (90) of the skirt (4) is closed by triangular star welding. 22. Method according to any one of claims 13 to 15, in which the housing (110) is made of plastic and in which the dome (112) is fixed to the upper end (116) of this housing (110) by rotary welding. 23. Method according to any one of claims 13 to 18, in which the housing (11; 211) is metallic and has at its upper end a rolled edge (16), the fixing portion of the dome (2) on the housing (11; 211) comprising a circular groove (6) fitting on this rolled edge (16), and in which said circular groove (6) made of plastic is fixed in leaktight manner to said metallic rolled neck (16). 24. Method according to claim 23, in which said fixing is carried out by surface treatment of said circular groove (6) followed by its bonding to said turtleneck (16). 25.A method according to claim 23, wherein there is between said turtleneck (16) and said circular groove (6) a connecting piece (23) compatible both with the metal of the turtleneck (16) and with the material plastic of the dome (2), and in that the welding of the dome (2) and the turtleneck (16) of the housing (11) is then carried out by a process of the group formed by: high frequency induction welding, the ultrasonic welding and rotational welding. 26. A method according to claim 25, in which the housing (11) is made of aluminum or alloy and the dome is made of polyolefin, said connecting piece (23) being made of plastic material containing EAA and said polyolefin; 27.A method according to claim 23, in which the circular groove (6,24) of the dome (2) extends to the vicinity of the end of the rolled edge (16) of the housing and in which the dome is secured ( 2) and said rolled edge (16) by annular lateral injection of plastic material of the same kind as that of the dome (2). 28.A method according to claim 23, in which an annular piece (25) of plastic material of the same kind as that has been disposed around the narrowed upper end (21) of the housing (11) before rolling its end edge dome (2), this part (25) comprising above a base (27) which rests on the shoulder (26) of the housing (11), an upper portion which will be crimped by the roll (16 ) of the end edge, of the housing (11), as well as one or more surfaces (29, 30) which will come into contact with the dome (2; 31) when placing said dome (2) on the housing; and in which the end edge (16) of the housing (11) is rolled around said upper portion (28) of said annular part (25), then the dome (2) is placed on the upper end ( 16) of the housing (11) thus prepared and the dome (2) and the said upper portion (28) of the said annular part (25) are fixed by welding by rotation. 29. Method according to any one of claims 1 to 12, in which the dome (2) is in polyolefin, and in which the skirt (4) pocket blank (13) is in complex comprising a barrier layer and layers of polyolefin surface compatible with the polyolefin of the dome (2). 30.A method according to claim 29, in which the reverse surface (32) of the dome (102) is provided with an annular barrier washer (33) fixed by molding, this washer (33) comprising at least surface layers in polyolefin compatible with the polyolefin of the dome (2) and an intermediate layer of aluminum or plastic barrier material. 31.Pocket dispenser (8) comprising a metal housing (11; 211) the bottom of which is pierced with a hole, this housing (11; 211) having at its upper end a rolled edge (16) and being surmounted by the dome (2; 312) made of plastic from a part preassembled in a sealed manner (dome + skirt) (1), this dome (2; 312) comprising a circular groove (6) by which it rests and is fixed so watertight on said rolled edge (16), this dome (2) being further fixed by its upper part (7; 70) to a valve (18) or to a low or no return air pump. 32. A dispenser according to claim 31, the metal housing of which is made of tinplate and comprises a tubular body (211) and a separate bottom (212), said bottom (212) being crimped or crimped onto said tubular body (211). 33. Pocket dispenser comprising a tubular plastic body (110) surmounted by the plastic dome (112) in one piece sealingly preassembled (dome + pocket) (112 and 13), the upper end (116) of said tubular body (110) being sealingly fixed to said dome (112) using one or more annular surfaces (113 ) being in contact with corresponding surfaces (114,117) of the dome (112), this dome (112) being further tightly fixed to a low or no return air pump (18) by crimping or by molding, said tubular body (110) ensuring the atmospheric pressure of the bag (13) when using the dispenser. 34.Pocket dispenser according to any one of claims 31 to 33, the part (dome + skirt) or (dome + pocket) being preassembled by molding. 35. Part preassembled by molding (dome + skirt (1; 101; 302 and 4) included in the dispenser of claim 34, the dome (2; 102; 112; 302) in polyolefin comprising an inner tube (5; 115; 325) fixed in leaktight manner by said molding to the end (3) of the skirt (4), the surface layers of which are made of polyolefin compatible with the polyolefin of the dome (2; 102; 112), the dome further comprising a portion fixing (6; 24) on the upper end (16; 116) of a housing (11; 110; 211) and an upper portion (7; 70) allowing the fixing of a valve or a pump ( 18). 36. The constituent sub-assembly of the dispenser of any one of claims 31 or 33, for filling the product with the top of the pocket, comprising a part pre-assembled by molding (dome + pocket) (2 + 13), the dome ( 2) being made of polyolefin and comprising an inner tube (5; 115) molded on the upper end (3) of the skirt (4) closed at its lower end (9) so as to form the pocket (13), the layers surface of said skirt (4) being of polyolefin compatible with the polyolefin of the dome (2), and further comprising a metal case (11) or a plastic case (110), said dome (2) being tightly fixed at the upper end (16; 116) of the housing (11; 110) and comprising an upper portion (7) allowing the attachment of a valve or a pump (18). 37. The constituent sub-assembly of the dispenser of claim 32, for filling the product with the lower end (9) of the skirt (4) before it is closed in a pocket (13), comprising a part preassembled by molding (dome + skirt ) (2; 102) fixed in a leaktight manner by its polyolefin dome part (2) both to a valve or to a pump (18) with little or no return air and to the upper end (16) of the tubular body of a metal housing (211) with separate bottom (212), said metal housing (211) having at its upper end a rolled edge (16) and said dome (2; 102) having a fixed circular groove (6) tightly on this rolled edge (16).

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