DE2155846A1 - A dispenser of a concentrate that can be actuated with a pressure medium and a method for producing this dispenser - Google Patents

Description

D-4000 DÜSSELDORF 1 PATENTANWÄLTE 2155846

Malkastenstrasse 2 DIPL.-ING. ALEX STENGER

DIPL.-ING. WOLFRAM WATZKE

Our Times: 12,621 Date: November 8, 1971

WILKINSON SWORD LIMITED, Sword Works, S out! Field, Road,

London W 4, England

A dispenser of a concentrate that can be actuated with a pressure medium and a method for producing this dispenser

The invention relates to a dispenser in the form of receptacles which can be operated with a pressure medium and which contains the Material and a propellant in the form of a volatile liquid, which latter is capable of in at room temperature to evaporate the container and thereby generate a pressure in this container, which the container contents after opening the Outlet valve of the container discharges or drives out.

The invention is particularly useful in spray mist dispensers, i.e. aerosol dispensers, namely in shaving foam dispensers, but generally advantageous wherever the propellant makes up only a small part of the contents of the container.

The invention thus relates to a dispenser which can be actuated with a pressure medium and which has a receptacle and its outlet is regulated and monitored by a valve, and which contains a concentrate and a reservoir with a propellant, this Reservoir contains an organic substance with which the propellant forms a solution. This is the pressure of the propellant smaller than that of the pure propellant over the entire solution. This organic substance is able to produce a Solution with at least 15 # of its own weight of the propellant at room temperature, the reservoir being able to absorb the dissolved propellant when the contents of the container are emptied to release in the container.

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Telephone (0211) J * OS14 · Tclegnmmadie · »: Dabqpitcnt · Poitichidckonto Cologne 227610

The invention also relates to a dispenser that can be actuated by a pressure medium, with a receptacle and its outlet is controlled and monitored by a valve, this receptacle containing a liquid mixture of a propellant and contains a concentrate and a reservoir in which a further propellant is housed. This receptacle contains an organic substance which is able to form a solution with at least 15 $ of its own weight of the propellant at room temperature, and the vapor pressure of the propellant throughout the solution is less than that of the pure Propellant, the reservoir being able to release gaseous propellant in the container in such a way that the pressure required to dispense the concentrate when the liquid mixture is maintained.

The invention also relates to a method of manufacture a dispenser which can be operated with a pressure medium and whose outlet is monitored by a valve. The procedure marks in that a reservoir formed from an organic substance is introduced into the receptacle of the dispenser, this substance being able to form a solution with the propellant, the vapor pressure of the propellant above the entire solution is smaller than that of the pure propellant, and this substance is capable of releasing dissolved propellant such that the pressure drop in the upper space of the receptacle is reduced during the discharge of the contents from this receptacle.

Under the term "concentrate" is all of the deliverable content of the receptacle to the extent that this content does not appear as a propellant. Under the term "reservoir" is to be understood as a device or a substance which is able to hold the propellant and which is used when the Concentrate is retained in the receptacle.

The invention is explained in more detail below with reference to the drawing explained. In this show in a purely schematic way:

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Pig. 1 shows a vertical section through a first embodiment an aerosol dispenser according to the invention;

2 shows a vertical section through a second embodiment the aerosol dispenser according to the invention;

Pig. 5 is a graph showing the effectiveness and the Port step of the invention shows.

The conventional form of one containing a sprayable foam The container, as shown in Fig.l of the drawing, has a pressure-resistant, bush-shaped receiving part 1 and a dip tube 2, which - starting from a valve 3 - extends in the direction of the bottom of this receiving part 1. The valve 3 monitors the throughput through a nozzle 4; it is controlled by means of a push button 5 that can be actuated with the finger. This can-shaped receptacle 1 receives a liquid mixture 6, which consists of a propellant and a concentrate. The latter, if it is a shaving cream, contains one strong soap solution. In this case, the propellant has a double function. It has to create the necessary pressure one day in order to transport the concentrate to the outside, and on the other hand, because it is contained in the concentrate in dispersed form, it evaporates it and in this way serves to form foam bubbles. In a new container there is about 8 $ of the propellant in the gas as a gas above the liquid level with the remainder of 92 # dispersed in this concentrate.

When the container is emptied, the propellant evaporates from the concentrate and fills the increasingly larger space above the liquid level. As a result, the proportion of propellant smaller in the remaining concentrate, so that the subsequent foam expansion when emptying this container is smaller. At the At the beginning this effect is negligible; when emptying the container, the liquid propellant rising into the upper space must be removed from come an ever decreasing volume of the concentrate. The density of the foam therefore increases faster when the container is nearing its exhaustion, so that the foam takes on a thin consistency.

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According to the invention, a container containing a propellant is provided, from which this propellant is discharged can as the volume in the top of the container becomes increasingly larger.

The selection of the appropriate material for this receptacle depends on the fact that the receptacle is capable of must be to form a solution with a substantial portion of the propellant; on the other hand, this receptacle must be able to be to allow a significant proportion of the dissolved propellant to evaporate in the direction of the space above.

The need for a receptacle to hold the propellant forms a solution is as follows:

It should also be assumed that a liquid propellant containing reservoir in the form of a can and the like above the level of the mixture of concentrate and propellant in one Receiving container lies. It is now known that when a volatile material is dissolved in a liquid such as a propellant in a shaving foam concentrate, the vapor pressure of the volatile solute normally drops. In this way, the Vapor pressure above the concentrate be lower than the vapor pressure above the reservoir of volatile liquid; the consequence it is that the propellant withdraws from the reservoir in the direction of the concentrate, namely by evaporation in the upper room. This is followed by dissolution in the concentrate. The same would happen if the reservoir were merely out would consist of a mass of sponge material, in whose pores the Propellant is absorbed. This pulling off or gassing takes place slowly, but would serve the purpose after a certain period of time question such a reservoir and adversely affect the properties of the discharged product. But if that Propellant is dissolved in the reservoir material, the vapor pressure of the propellant drops across the entire reservoir, so that an equilibrium between the vapor pressure over the whole

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Reservoir and the vapor pressure over the concentrate / propellant mixture is made away.

Although many organic substances can be used that are able to dissolve and apply the propellant to form the reservoir, the economy "requires that the Propellant of the receptacle is able to form a solution with at least $ 15 dead weight of the propellant when it is in contact with the liquid propellant or a saturated vapor at room temperature. Such an organic substance will also normally be able to release a significant amount of dissolved propellant due to the vapor pressure of the propellant drops down to 60 # of its original value in a container under pressure. Such a significant one Proportion is considered to be the weight of propellant, which is $ 5 des (which is equal to the organic matter.

The amount of propellant dissolved at saturated vapor pressure gives one useful indication of the amount released during a pressure drop. Some types of natural rubber or synthetic rubber meet these above mentioned criteria with ease. Table I shows the behavior of some commercially available rubbers or elastic polymers.

Table I.

Weight of the dissolved propellant in loo g
Gum at room temperature, saturated steam
pressure Propellant
11 12th 114 4o / 6o
12/114 Rubber-
jroben butane
4o 37o
6oo
disintegrates """
liquefied
themselves
liquefied
themselves
not
measured 68 "
'82
84
148
80
not
measured ^ 5o -——
~ si """~
37
23
14th
"not
measured 'zM - Sample Ä
Sample B 61 . h .
5o
51; ■■■ -
-33-- Sample C
Sample D
Sample E.
Sample F.
Sample G 155
"Qo
liquefied
themselves
'"61

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The propellants mentioned above are:

Butane 4o, which is known as a mixture of hydrocarbons and contains predominantly butane and isobutane;

Propellant 11, which is trichlorofluoromethane acts;

Propellant 12, which is diehlorodifluoromethane acts;

Propellant 114, which is a symmetrical "dichlorotetrafluorathane". The propellant can be used by itself or in the form of a 40 % / 6o ^ mixture of propellant 12 and propellant 114.

The samples mentioned above are the following samples:

Sample A is a translucent, i.e. translucent, silica-filled silicone rubber, which in general for laboratory use and for surgical devices and Apparatus is used.

h Sample B is slightly vulcanized

Mass, which contains $ 75 high quality natural rubber.

Sample C is a slightly cross-linked hydrocarbon rubber, which consists of a pre-vulcanized natural rubber latex.

Sample D is a rubber sheet or rubber jersey, which consists of unvulcanized natural rubber latex.

The sample E is a thermoplastic rubber, which by Block copolymerization of isoprene and styrene is obtained.

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The sample P is a polyisobutylene with a viscosity dependent Average molecular weight of 1,300,000.

Sample G is a thermoplastic rubber made by block copolymerization of butadiene and styrene will.

In those cases where the reservoir is made of rubber or similar material, the reservoir is primary homogeneous, the nature of most of the materials for this reservoir allowing the overall shape of the reservoir to be maintained, without collapsing when a bulging occurs when the propellant dissolves. If necessary, the material can stiffened and reinforced by the absorption of fillers Fillers can be inert or consist of less deformable, active organic materials. However, if the solution of the propellant and the reservoir are slightly liquid, the propellant can be stored in a capsule, the walls of which for the Propellants are easily permeable, but not with regard to the reservoir material. As an example of such a reservoir can a capsule made of polyethylene containing microcrystalline hydrocarbon wax can be selected, this capsule being able to then expand as the liquid propellant solution forms.

It must be remembered that the function of the reservoir in a dispenser containing a concentrate-propellant mixture lies in the entire part or at least a substantial part of an added excess propellant in the replenished Dissolve the dispenser and release a substantial portion of the dissolved excess propellant when the pressure in the container falls as a result of the leakage of part of the container contents.

The examples below show that by appropriate choice of reservoir and an extra amount of propellant improves the performance of the dispenser without sacrificing the properties of the discharged Substances are affected.

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Example I.

A shaving foam was prepared as follows: A tinplate container with a capacity of 220 milliliters was filled with 150 g of a concentrate having the following composition in percent by weight: stearic acid 4.5 # l lauric acid 4.0 #; Triethanolamine J>, 5%; "PCL liquid" (a plasticizing oil supplied by Dragooo Ltd.) 2.5 #; Sodium lauryl ether sulfate $ 0.4; Water up to loo #. The container was then cleaned, after which the valve was inserted and the propellant 12/114 (ratio 4o: 6o) was added, 14.0 g being added via the valve.

A second container was then filled in exactly the same manner except that a silicone rubber reservoir weighing 7.6 grams was attached to the valve assembly, the weight of the propellant being 21.0 grams.

Both receptacles were stored at room temperature for three weeks; then the contents were emptied in a manner similar to that of that corresponds to normal consumption. The container with the additional reservoir delivered 1.78 liters of foam, the density of which was in the range of 8o up to loo g per liter, while the container without additional Reservoir released only 1.24 liters of foam of the same density.

Figure 3 shows the curve of the foam density Y in grams per Liters above the amount of foam expelled, plotted on the abscissa X in grams. This diagram shows that the container irtfc a reservoir (curve B), the foam density is much more constant holds as an equivalent container without such a reservoir (curve A) especially when the container contents are running low.

Example II

The aforementioned example was repeated except that the receptacle was filled with 6.0 g of butane 4o as propellant without an additional reservoir and that a film was used as the reservoir, a strip or sheet of thermoplastic rubber was chosen ("CARIEFLEX Hol", which is available from Shell Chemicals Ltd.)

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was delivered in England). The weight of this film or plate was lo, o g, whereby the receptacle with reservoir with 8.0 g of butane 4o was added as a propellant. The receptacle without a reservoir gave a foam with a density of 70 to 134 g per liter, while the receiving container with reservoir provided a foam with a density of 76 to 10 4 g per liter.

Example III

This example shows the use of a reservoir in a dispenser that dispenses dry powder. A reservoir, which held 12 g of a propellant mixture, which consisted of 40 # propellant 12 and 6o% propellant 114 and which were dissolved in a piece of silicone rubber weighing 6 g, was attached to a valve / dip tube, which in turn was in a receptacle of 8o milliliter content was attached. This receptacle contained 12 g of fine talc.

A similar container or can containing 12 grams of fine talc was made not equipped with a reservoir, but contained 12 g of the same propellant that was injected through the valve when the latter was used. Thirty minutes after packaging, the pressure in the receptacle with reservoir was 2.2 atmospheres, while the pressure in the receptacle without a reservoir was 2.7 atmospheres.

Both receptacles were operated in the normal way for so long until 7 g of the content has been expelled. Both receptacles were then operated in an overturned position for ten minutes, wherein After this period, none of the receptacles was able to dispense the powder in a usable amount because of the pressure in the container has dropped almost to the ambient pressure.

After allowing the containers to stand for twenty minutes, rose the pressure in the first container up to 1.5 atmospheres, but in the second container only up to 1.2 atmospheres. Both receptacles were re-operated for ten minutes in an overturned position. After another twenty downtime

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- Io -

Minutes the pressure rose to 1.4 atmospheres and 0.3 atmospheres, respectively at. The container that did not contain a reservoir did not release any further significant amounts of talc, while that of a reservoir Containers containing pretty much all of the remaining talc expelled.

The external shape that the reservoir adopts changes accordingly the stuff of which it is made. In those cases in which the reservoir material - whether with or without fillers - Does not flow in the presence of the dissolved propellant, the reservoir can be designed in the manner shown in Fig.l * will. The reservoir can be in the form of a single mass 7 or have a plurality of separate masses 8; the reservoir but can also be designed as a covering 9 attached to the inner wall of the receptacle. The main criterion is that the Reservoir does not interfere with the operation of the immersion tube or valve.

If a single mass is to be provided, then the reservoir Have ring shape, this special reservoir shape is dimensioned so that in the bulged state, when the propellant is dissolved, the propellant settles inside the container. Alternatively, the reservoir can be designed so that it is on the Immersion tube fits. In many cases the reservoir preferably has a large surface area for dissolution and subsequent expulsion P deft propellant to facilitate. But if the concentrate is thick, you should avoid an overly large surface, otherwise Concentrate losses can occur through adhesion to the reservoir.

FIG. 2 shows a container in which the reservoir is movable Contains a solution of a propellant and an organic substance, this organic substance in a capsule or in a Pouch Io is included, which consists, for example, of polythene. This capsule can lie loosely in the receptacle; but it is preferably connected to the dip tube, as shown in FIG Drawing shows.

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The receptacle can be filled with propellant before or after the propellant is poured into the receptacle. occurs. In the simplest way of producing a dispenser of the type in which the concentrate and the propellant interact with one another are mixed, the concentrate and the propellant is introduced into the receptacle with the propellant excess, and that The reservoir then dissolves this excess propellant after the filling process gradually on.

Alternatively, however, the reservoir with a propellant outside of the receiving container and then introduced into the receiving container, before or after the concentrate was introduced. This is particularly useful when the concentrate is a powder which is mixed with the liquid propellant should not come into contact.

As the reservoir gradually releases propellant into the upper space, and although normally in an amount that is considerably less than the flow through the valve, the reservoir protects the Dispenser in case of abuse by opening the valve, if the receptacle is overturned because - although in this case there is a sudden drop in pressure - this pressure after closing of the valve is largely restored by slowly evaporating the propellant in the reservoir.

As a further alternative embodiment of the reservoir, a Part or an element of the dispenser which is in the receptacle is included, e.g., the dip tube or the container valve, made at least partially from one of the organic substances which are indicated above as being particularly suitable for the reservoir. The invention hereafter also includes parts of with one Dispensers which can be actuated by pressure medium, the former consisting at least partially of such an organic substance.

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Claims (8)

Claims A dispenser of a concentrate that can be actuated by a pressure medium, with a receptacle, the outlet of which is from a valve is regulated, characterized in that a reservoir is provided which has an organic Contains substance with which the propellant forms a solution, the vapor pressure of the propellant across the solution is smaller than that of the pure propellant that this organic substance is able to produce a solution with at least 15 $ to form their own weight of the propellant at room temperature and that the reservoir is capable of emptying of the contents in the container to release the dissolved propellant in the container. 2. Dispenser according to claim 1, characterized in that the concentrate contains the propellant dissolved in this, which is in equilibrium with the propellant dissolved in the reservoir stands. 3. Dispenser according to claim 1 or 2, characterized in that the Reservoir is formed from a solid, homogeneous mass of an organic substance in which the propellant is dissolved ^ will. 4. Dispenser according to claim 1 or 2, characterized in that the reservoir is a capsule whose shell for the propellant is permeable and absorbs a solution consisting of the organic substance and the propellant. 5 dispenser according to one of the preceding claims 1 to 4, characterized in that a silicone rubber is used as the organic substance. 6. Dispenser according to one of the preceding claims 1 to 5, characterized characterized in that hydrocarbon rubber is provided as the organic substance. 209821/0673 7. Dispenser according to one of the preceding claims 1 to 6, characterized in that the organic substance is in the form of a coating on the inside of the receptacle or but has the form of a mass, loose or with the Receiving container is connected. 8. A method for producing a valve-monitored, actuatable with a pressure medium dispenser according to claim 1 to 7, characterized in that an organic substance is introduced into the receptacle, which is able to form a solution with the propellant and thereby the vapor pressure of the To reduce propellant over the entire solution below the value of the vapor pressure of the pure propellant and to release dissolved propellant in such a way that the pressure drop in the upper space of the receptacle is reduced during the discharge of the contents from this receptacle. 9 »Method according to claim 8, characterized in that at least part of the propellant is dissolved in the organic substance before the latter is introduced into the receptacle. 209821/0673