MXPA06011155A - Aerosol - Google Patents

Abstract

A spray head for attachment to an aerosol container containing pressurised product is provided, the spray head comprising conduit means, more than one separate spray outlet and a splitting chamber for diverting the flow to the spray outlets, wherein the conduit means comprise inlet means for attachment to a valve stem of the aerosol spray unit and conduit outlet means which are in direct fluid communication with the splitting chamber, wherein the splitting chamber is in fluid communication with the spray outlets and wherein, for each spray outlet, the ratio, L1/L2, of the distance (L1) between the conduit outlet means and the spray outlet to the distance (L2) between the inlet means and the spray outlet is in the range 0.01 to 0.6.

Description

AEROSOL FIELD OF THE INVENTION The present invention relates to an aerosol spray head, an aerosol spray unit comprising the aerosol spray head and a process for spraying pressurized product.

BACKGROUND OF THE INVENTION A conventional approach to dispatch a product on a target application surface is through the atomization of that product. One way to achieve atomization is through the combination of the product with a propellant (compressed gas) in a pressurized unit that has a delivery valve in continuous fluid connection with a delivery outlet. When opening the dispensing valve, the product is forced through it and dispensed through the outlet in atomized form on the target application surface. The present inventors have established, however, that current atomization technology in general does not deliver a satisfactory distribution of product over the target area. In particular, it is observed that the distribution is not even with, for example, an increase in deposit occurring in the center and a corresponding decrease in deposit toward the ends of the target site. In addition to the unequal dispersion of the active agent and the resulting unequal achievement of benefit throughout the target site, the increase in deposit in an area, for example the center, can also result in the formation of unsightly residues and unpleasant cooling in that area. region of the consumer's skin, due to the increase in the amount of product deposited there and the increase in the amount of propellant that evaporates in that location. In addition to the deficiencies already mentioned, a single outlet sprayer head also determines physical limitations on the composition that can be sprayed. In particular, high viscosity compositions may not be practically sprayed, because in said fluid sufficient energy can not be retained under normal pressurization conditions, so that it can be sufficiently atomized as it leaves the spray outlet. With reference to the patent of no. USA 3,767,125, a multi-outlet spray head is proposed for spraying dry powder aerosols. With reference to the U.S. patent no. 5,516,045, there is described a multiple outlet spray head, especially for spraying hairspray. It would be advantageous to provide a spray head that overcomes the disadvantages of the spray heads described in the prior art.

BRIEF DESCRIPTION OF THE INVENTION According to a first aspect of the invention, there is provided a spray head for attachment to an aerosol container containing pressurized product, the spray head comprises driving means, more than a separate spray outlet and a divider chamber for diverting the flow of the sprinkler outlets, wherein the driving means comprise input means for fastening to a valve stem of the aerosol spray unit and conductive output means that are in direct direct communication with the divider chamber, wherein the divider chamber is in continuous communication with the sprinkler outlets and where, for each sprinkler outlet, the ratio L1 / L2 of the distance (L1) between the conductive outlet means and the sprinkler outlet to the distance (L2) between the input means and the Sprinkler outlet is from 0.01 to 0.6. According to a second aspect of the invention, there is provided a pressurized aerosol spray unit, having a spray head as defined in the first aspect of the invention. According to a third aspect of the invention, there is provided a portable aerosol spray unit, having a spray head as defined in the first aspect of the invention. According to a fourth aspect of the invention, there is provided a process for spraying a pressurized product, comprising the steps of spraying said product through a spray head in accordance with the first aspect of the invention, such that the product It has a Reynolds Number of at least 1000 when it exits through said sprinkler exits. These and other attributes, aspects and advantages of the present invention will be apparent to those with experience in the industry from reading the present description.

BRIEF DESCRIPTION OF THE FIGURES Although the specification concludes with claims that particularly state and clearly claim the invention, it is believed that the present invention will be better understood from the following description of preferred embodiments, which are taken together with the accompanying figures, in which the numbers of identical reference identifies identical elements and in which: Figure 1 is a cross-sectional view of a spray head according to the invention. Figure 2 is an enlarged cross-sectional view of the important parts of the spray head according to the invention.

DETAILED DESCRIPTION OF THE INVENTION Even though the specification concludes with the claims that in a particular manner clearly state and claim the invention, it is believed that it will be better understood from the following description. All weights, measures and concentrations herein are measured at 25 ° C in the total composition, unless otherwise specified. Unless indicated otherwise, all percentages of the compositions mentioned herein are percentages by weight of the total composition (i.e. the sum of all components present) and all proportions are weight proportions. Unless indicated otherwise, the content of all literature sources mentioned in this text is incorporated in its entirety as a reference. Except in cases where specific examples of actual measured values are offered, the numerical values quoted here should be considered qualified with the word "approximately". As it has been seen, a limitation of the traditional configurations of aerosol spray heads is that they can produce an unequal distribution of product on the target site. In addition, the viscosity of the product to be sprayed can be practically restricted to remain below a certain level.

By introducing instability in the fluid flow at a first stage, it is possible to atomize products with higher viscosities and, at the same time, improve the distribution of the product on the target site. The replacement of a single spray outlet by multiple outputs can help introduce such instability, because, for a given volume of product flow, the size of the friction interface (ie, the total size of the exit perimeter) is greater for multiple outputs than for a single output. Without wishing to be bound by theory, it is believed that this measure can prevent the formation of a smooth film structure just outside the exit where the product begins its journey to the target site. The disadvantage of a soft film structure is that it can propagate a relatively thick atomization in the final stage before the product reaches the target site, with the drops in the center of the spray being larger than those near the periphery. It is in the final stage of dew formation that an instability in the system can help to disintegrate the product into ligaments and then into drops to form a highly atomized spray and a better distribution of droplets. Furthermore, in a multiple-outlet system, it is observed that, after splitting the flow into pipelined fluid in the separate orifices, changes in the separate flows may occur such that there may be differences, for example, in viscosity or other parameters, between what is sprayed from one outlet and what is sprayed from the other or others. If there are differences between the individual sprays immediately after they exit through their respective spray outlets, this can translate into differences in the distribution of the product at the target site. Without wishing to be bound by theory, it is believed that these changes can be caused by manufacturing limitations. In other words, it is very difficult to ensure that the ducts through which the flow travels are identical. To counteract this, it has been found beneficial to locate the point at which the flow divides to address two or more separate spray outlets near the spray outlets, so that most of the flow within the spray head occurs earlier. of the division. To be more specific and as described above, it has been found to be beneficial to design a spray head (1) such that the ratio L1 / L2 for each spray outlet (3) of the distance (L1) between the conductive outlet means and the spray outlet (3) with the distance between the inlet means (5) and the spray outlet (3) is 0.01 to 0.6, preferably 0.015 to 0.4 and more preferably 0.02 to 0.4. In the case that the conductors and / or conduits leading to the sprinkler outlets have a non-constant cross-sectional area such that each or both of L1 and L2 can vary depending on the measurement line, then the measurements should be performed along the center line connecting the centers of the input means (5), the conductive outlet means and the respective spray outlet (3). In a preferred embodiment, at least one of the spray outlets has a ratio L1 / L2 that is different from the other or others. In another preferred embodiment, all sprinkler outlets have the same ratio L1 / L2.

Advantageously, at least one of the spray outlets and preferably all the spray outlets are not circular. Employing non-circular sprinkler outlets can also help introduce instability early in the flow, thereby improving distribution at the target site. As used herein, the term "circle" should be understood as a closed flat curve at each point that is equidistant from a fixed point within the curve and the word "circular" should be interpreted in the same way. The spraying outlets (3) may not have a circular shape, but advantageously have a cross sectional shape selected from a group comprising polygons, semicircles, half moons, stars and mixtures thereof. If they are polygons, then each polygonal cross-sectional shape can advantageously be selected from a group comprising polygons having three to ten sides. Preferably, the polygons are selected from a group comprising triangles, rectangles, pentagons, hexagons and mixtures thereof. The spray head (1) according to the invention can have any number of spray outlets (3) above two, but preferably has from 2 to 36 and more preferably from 3 to 12 spray outlets (3). According to a second aspect of the invention, there is provided an aerosol spray unit (10) comprising a pressurized product to be dispensed and having a spray head (1) in accordance with the first aspect of the invention. As used herein, the term "spray unit" is to be understood as a pressurized aerosol canister, which comprises a valve, the stem of the valve projecting from the canister, usually at the upper end. Such cans usually have a volume of up to 1000 mL, although more generally below 200 mL and are generally pressurized from 103 kPa to 552 kPa (15 to 80 psi), more generally less than 414 kPa (60 psi). . As used herein, the term "product" should be understood as all components of the composition or mixture contained within the spray unit, including all active agents, all carrier materials and all propellants. Preferably, the product to be dispensed is a cosmetic product, more preferably it is selected from a group comprising antiperspirants, deodorants and mixtures thereof. If the product to be dispensed is an antiperspirant, then it can comprise antiperspirant active particles and a carrier such that the antiperspirant active particles are not soluble in the carrier. Alternatively, the antiperspirant active can be solubilized in the carrier. According to a third aspect of the invention, there is provided a portable aerosol spray unit (10) comprising a pressurized product to be dispensed and a spray head (1) in accordance with the first aspect of the invention. As used herein, the term "portable" is used in connection with an aerosol spray unit that can be easily transported in one hand by a single adult person of common strength. According to a fourth aspect of the invention, there is provided a process for spraying a pressurized product comprising the steps of spraying said product through a spray head having at least two separate spray outlets (3), whereby at less one of the spray outlets (3) has a non-circular cross section, such that the product has a Reynolds Number of at least 3000 when it exits said spray outlets (3). It is understood that the examples and embodiments described in the present invention are for illustrative purposes only and that in the light of the same to a person with experience in the industry various changes and modifications will be suggested without departing from the scope of the present invention. All documents cited in the Detailed Description of the Invention are incorporated, in its relevant part, as reference in the present. The citation of any document should not be construed as being prior industry with respect to the present invention. To the extent that any meaning or definition of a term in this written document contradicts any meaning or definition of the term in a document incorporated by reference, the meaning or definition assigned to the term in this written document shall govern. While particular embodiments of the present invention have been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. It has been intended, therefore, to cover in the appended claims all changes and modifications that are within the scope of the invention.

Claims (17)

NOVELTY OF THE INVENTION CLAIMS

1. A spray head for attaching to an aerosol spray unit containing pressurized product, the spray head comprises driving means, more than a separate spray outlet and a divider chamber for diverting the flow to the spray outlets, wherein the driving means comprises driving inlet means for attachment to a valve stem of the aerosol spray unit and conduction output means which are in direct direct communication with the divider chamber, wherein the divider chamber is in continuous communication with the spray outlets , and wherein for each sprinkler outlet, the ratio L1 / L2 of the distance between the conductive outlet means and the sprinkler outlet with the distance (L2) between the inlet means and the sprayed outlet is 0.01 to 0.6.

2. The spray head according to claim 1, further characterized in that the length ratio (L1 / L2) is 0.015 to 0.4.

3. The spray head according to any of the preceding claims, further characterized in that at least one of the spray outlets has a ratio L1 / L2 that is different from the other or others.

4. The spray head according to any of the preceding claims, further characterized in that the sprinkler outlets have the same ratio L1 / L2.

5. The spray head according to any of the preceding claims, further characterized in that at least one of the spray outlets has a non-circular cross-section.

6. The spray head according to any of the preceding claims, further characterized in that all the spray outlets do not have a circular cross-sectional shape.

The spray head according to any of the preceding claims, further characterized in that one or more of the spray outputs has a selected cross-sectional shape of polygons, semicircles, half-moons, stars and mixtures thereof.

The spray head according to any of the preceding claims, further characterized in that each polygonal cross-sectional shape is selected from polygons having three to ten sides.

The spray head according to any of the preceding claims, further characterized in that each polygonal cross-sectional shape is selected from triangles, rectangles, pentagons, hexagons and mixtures thereof.

10. The spray head according to any of the preceding claims, further characterized by having from 2 to 36 outputs.

11. An aerosol spray unit comprising a pressurized product to be dispensed and having a spray head according to any of the preceding claims.

12. The spray head according to any of the preceding claims, further characterized in that the product to be dispensed is a cosmetic product.

13. The spray head according to any of the preceding claims, further characterized in that the product to be dispensed is selected from antiperspirants, deodorants or mixtures thereof.

The spray head according to any of the preceding claims, further characterized in that the product to be dispensed is an antiperspirant composition comprising antiperspirant active particles and a carrier, wherein the antiperspirant active particles are not soluble in the carrier.

15. The spray head according to any of the preceding claims, further characterized in that the product to be dispensed is an antiperspirant composition comprising an antiperspirant active and a carrier, wherein the antiperspirant active is solubilized in the carrier.

16. The spray head according to any of the preceding claims, further characterized in that the spray unit is a portable spray unit.

17. A process for spraying a pressurized product comprising the steps of spraying the product through a spray head according to any of the preceding claims, such that the product has a Reynolds number of at least 3000 upon exiting. by the sprinkler exits.