JPS5990658A - Aerosol sprayer - Google Patents

Abstract

PURPOSE:To enable spraying of a stable mist having the same compsn. in an aerosol device consisting of a pressurization chamber and a content contg. chamber by packing liqueified gas in such a way that the pressure in the pressurization chamber attains the pressure in the content contg. chamber or above in the stage of use. CONSTITUTION:An aerosol stock soln. and <=15% spraying agent based on the volume of said stock soln. are packed in a content contg. chamber 3 and liquefied gas 7 is packed in a pressurization chamber 4 so that the pressure in the chamber 4 attains the pressure in the chamber 3 or above in the stage of use in an aerosol sprayer consisting of said chamber 4 and chanmber 3. More specifically, if the content is sprayed through the valve 5 of an aerosol vessel 1, the volume of the content occupying in the chamber 3 decreases and the pressure in the chamber 3 is going to decrease by as much as the decreased volume but the liquefied gas in the chamber 4 equivalent to the decreased volume of the content in the chamber 3 evaporates, thereby maintaining the equil. state between the chamber 3 and the chamber 4, whereby the pressure in the chamber 3 is maintained approximately constant until the content is fully sprayed and the stable mist or foam having the same compsn. is sprayed to the last.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an aerosol product injection device, and more particularly to a device that injects an aerosol product as a stable mist or foam of the same pressure and composition throughout.◇ Generally, aerosol products are Freo y (F
'reon) -32, Freon-1', Freon-1
Fluorinated chlorinated hydrocarbons such as 14 (trade name of a DuPont product), liquefied gases such as propane, isobutane, n-butane, methyl ether, carbon dioxide gas, laughing gas (N20
), a compressed gas such as nitrogen is dissolved or dispersed in a raw liquid in a container, forming a mist or foam when the pulp in the container is opened and injected by internal pressure.

By the way, among aerosol products, the propellant is 40 to 50%
In the case of insecticides, hair sprays, etc. that contain more than % of the spray, the pressure inside the container is maintained above a certain level from the beginning to the end of spraying, so that a stable mist or foam with the same composition can be obtained until the end.

On the other hand, aerosol products such as shaving foams and glass cleaners generally have a propellant content of less than 15% due to the low solubility of the gas in the stock solution.
In these products, before use, the volume of the contents, including gas, occupies 70 to 90 volumes of the container, but as they are used, the volume occupied by the contents decreases, and conversely, the volume occupied by the space phase increases. do. As a result, the pressure inside the container decreases by the increased volume of the spatial phase, and to compensate for this, the liquefied gas dissolved or dispersed in the stock solution evaporates to maintain an equilibrium state. However, such evaporation reduces the gases dissolved or dispersed in the concentrate, which may result in changes in the composition of the mist or foam of the aerosol product that is sprayed outside the container, or in some cases, the mist or foam. The gas may be sprayed as a liquid without forming foam, or it may remain in the container due to insufficient gas pressure. In addition, when a compressed gas such as nitrogen gas that is hardly soluble in the stock solution is used as a propellant, the spray condition deteriorates significantly, and when a compressed gas such as carbon dioxide that is slightly soluble in the stock solution is used as a propellant. Similar deterioration cannot be avoided in any case.

In order to solve the above problems, a device has been proposed that prevents the internal pressure from decreasing due to the increase in the spatial phase by providing a liquefied gas filling tank inside the aerosol container (
For example, Japanese Patent Publication No. 50-26773, Japanese Patent Publication No. 51-2
3052, etc.).

However, these liquefied gas replenishment devices have a complicated structure, and not only cannot be expected to operate accurately, but also have the disadvantage that their manufacturing costs are high.

An object of the present invention is to provide an apparatus that prevents pressure reduction in a customer container due to the spraying of an aerosol product and sprays stable mist or foam having the same pressure and composition from beginning to end.

The present invention provides an aerosol injection device consisting of a pressurized chamber and a content storage chamber, in which the content storage chamber is filled with an aerosol stock solution and a propellant of 15% or less with respect to the stock solution, and when in use, the pressurization chamber is It has been found that the above object can be achieved by filling the pressurized chamber with liquefied gas so that the pressure is higher than the pressure of the content storage chamber.

That is, according to the present invention, when the content is injected through the valve of the aerosol container, the volume of the content occupying the content storage chamber decreases, and the pressure in the content storage chamber tends to decrease by the volume. At that time, the liquefied gas in the pressurized chamber evaporates and vaporizes, corresponding to the volume reduction of the contents of the storage chamber, and the equilibrium state between the contents storage chamber and the pressurized chamber is maintained, and the pressure inside the chamber is reduced to the point where all the contents are It remains approximately constant without any drop until it is injected, allowing a stable group or foam of the same composition to be injected throughout.

The aerosol injection device of the present invention is an injection device W consisting of an upper content storage chamber and a lower pressure chamber separated by a piston (see Figure 1), or a content storage made of aluminum foil, plastic film, etc. This includes a partition type injection device consisting of a chamber and a pressurized chamber surrounding the chamber. Also,
In the apparatus of the present invention, examples of the liquefied gas to be filled in the pressurizing chamber include Freon 11, Freon 12, Freon 1t4, liquefied fluoropane, isobutane, n-butane, dimethyl ether, etc. Preferably, the pressure is also higher, for example from 0 to about 1 kg/am''.

Embodiments of the invention will now be described with reference to the accompanying drawings.

FIG. 1 is an explanatory diagram showing an embodiment of the device of the present invention, and an aerosol container 1 is composed of a piston 2, a partition Jl, a content storage chamber 3, and a pressurization chamber 4.

In the content storage chamber 3, 4.8 parts of stearic acid (&i, the same applies hereinafter), 3.2 parts of myristic acid, and 1.0 parts of cetyl alcohol.
0 parts, polyoxyethylene sorbitan stearate 2,
0 parts, triethanolamine 3.2 parts, glycerin 4.
Aerosol stock solution consisting of 0 parts, 07 parts of polyvinylpyrrolidone, 01 parts of menthol, 0.2 parts of fragrance and 800 parts of water, and Freon 12/114 (60/40 mixture)
Fill 105 parts of propellant and pressurize chamber 4 with freon/
Butane liquefied gas was filled in so that the liquefied gas 7 remained at the bottom. The pressure inside the content storage chamber is 4.2 kg/
(yB2, the viscosity of the aerosol stock solution was 1000 centivoise (OC), and the pH was 8.1.

Next, the valve 5 of the aerosol container 1 was opened to inject the contents, and the temporal changes in the pressure (PA) in the content storage chamber and the expansion rate (OA) of the injected foam were measured. As shown by the lines PA and OA in the figure, the pressure inside the content storage chamber hardly changes, and the expansion rate of the bubbles remains almost constant.

For comparison, we conducted an experiment with the same Φ conditions as above, except that we used an ordinary aerosol container without a liquefied gas tank and an aerosol container with a liquefied gas filling tank inside. As shown by the line PC1OC in Figure 2, the pressure inside the M4 vessel (Pc) and the bubble expansion rate (○C) change over time.
For aerosol containers with tanks, the pressure inside the container (
PB) decreased slightly, and the foam expansion rate (OB) was not constant and changed in a zigzag pattern.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of the device of the present invention, in which symbol 2 indicates an aerosol container, 2 indicates a piston, 3 indicates a content storage chamber, 4 indicates a pressurizing chamber, 5 indicates a valve, and 6 indicates a bubble. FIG. 2 is a chart specifically showing the effects of the device of the present invention in comparison with a comparative example. Person P--Pressure PB in the content containment system of the device of the present invention--
-Aerosol capacity with tank 2: Pressure pC in a normal aerosol container --- Pressure 0A in a normal aerosol container --- Bubble expansion rate OB when using the device of the present invention --- When using an aerosol container with a tank Bubble expansion rate ○c --- Bubble expansion rate when using a normal aerosol container (3 other people) No. 11g A 11 L' /-4

Claims (1)

[Claims] In an aerosol injection device consisting of a pressurized chamber and a content storage chamber, the content storage chamber is filled with an aerosol stock solution and a propellant of 15% or less with respect to the stock solution, and the pressure in the pressurization chamber is lower than the content during use. An aerosol injection device characterized in that a pressurized chamber is filled with liquefied gas so that the pressure is equal to or higher than that of a storage chamber.