Title:  Aerosol preparation

United States Patent:  6,133,327

Assignee:  Taisho Pharmaceutical Co., Ltd. (JP)

Filed:  June 12, 1998

PCT NO:  PCT/JP96/03631

102(e) Date:  June 12, 1998

PCT PUB. Date:  June 19, 1997

Foreign Application Priority Data:  Dec 14, 1995[JP]

An aerosol preparation which when sprayed forms a sherbet-like solid, which comprises a concentrate containing a lower alcohol having 1 to 3 carbon atoms and a higher alcohol having at least 12 carbon atoms and a propellant containing a liquefied gas. Said aerosol preparation does not require any complicated emulsifying procedure for the production, can contain components labile in water and have a durable cooling effect, and therefore, it is quickly calmative on the pain caused by contusion, sprain, muscular fatigue, etc. and the itch caused by athlete's foot, insect bite, etc.

DISCLOSURE OF THE INVENTION

As a result of extensive research in order to solve the above-mentioned purposes, the present inventors have found that an aerosol preparation comprising a lower alcohol, a higher alcohol and a liquefied gas does not require an emulsifying procedure for the production and has a durable cooling effect because the aerosol preparation forms a sherbet-like solid when sprayed, and whereby the present invention has been accomplished.

That is, the present invention relates to an aerosol preparation which when sprayed forms a sherbet-like solid, which comprises a concentrate containing a lower alcohol having 1 to 3 carbon atoms and a higher alcohol having at least 12 carbon atoms, and a propellant containing a liquefied gas.

Any known aerosol preparations form a solid, when sprayed, by freezing water which is contained therein, on the contrary, the aerosol preparation of the present invention does not always necessarily contain water, and it is characterized by that the aerosol preparation forms a solid under entirely new conditions when sprayed.

According to the aerosol preparation of the present invention, the higher alcohol which is cooled by the heat of vaporization of the liquefied gas including the lower alcohol forms a sherbet-like solid when sprayed.

In the present invention, the lower alcohol having 1 to 3 carbon atoms means a straight or branched alcohol, for example, methanol, ethanol, denatured ethanol, propanol, isopropanol, etc., and preferably ethanol. The amount of the lower alcohol is preferably 0.3 to 65% by weight based on the total amount of the preparation, more preferably 1.5 to 50% by weight and most preferably 15 to 35% by weight. If the amount of the lower alcohol is less than 0.3% by weight, the concentrate cannot be easily mixed with the propellant homogeneously. If the amount of the lower alcohol is more than 65% by weight, since the amount of the propellant is relatively reduced, the cold feeling is reduced.

The higher alcohol having at least 12 carbon atoms of the present invention means a straight or branched alcohol which can be homogeneously mixed with other components, for example, lauryl alcohol, cetanol, stearyl alcohol, cetostearyl alcohol, behenyl alcohol, lanolin alcohol, hydrogenated lanolin alcohol, etc, they may be used alone or by mixture with each other, and stearyl alcohol or cetanol is preferable.

The amount of the higher alcohol is preferably 0.005 to 14% by weight based on the total amount of the preparation, more preferably 0.015 to 10% by weight and most preferably 0.5 to 5% by weight. If the amount of the higher alcohol is less than 0.005% by weight, since the aerosol preparation cannot easily form the solid when sprayed, the durable cold feeling is reduced. On the other hand, if the amount of the higher alcohol is more than 14% by weight, since the higher alcohol cannot be easily dissolved, the production procedure is complicated.

The higher alcohol must be absolutely dissolved in the lower alcohol and the liquefied gas so as to give a homogeneous system, and whereby the effect of the present invention can be achieved. For the purpose, when the higher alcohol cannot be sufficiently dissolved, it is possible to contain other solvents or solubilizing agents (e.g. polyoxyethylene alkyl ether, polyoxyethylene hydrogenated castor oil, diisopropyl adipate, isopropyl myristate, 1,3-butyleneglycol, propyleneglycol, polyethyleneglycol, glycerin, lactic acid, sodium hydroxide, etc.).

The liquefied gas is any one which can be used as a propellant for an ordinary aerosol preparation, but preferably dimethyl ether, n-butane, i-butane, propane or a liquefied petroleum gas, and they can be used alone or by mixture with each other. The amount of the liquefied gas is preferably 30 to 95% by weight based on the total amount of the preparation, and more preferably 50 to 85% by weight. If the amount of the liquefied gas is less than 30% by weight, the cold feeling by the aerosol preparation is reduced, and whereby the calming effect of pain and itch is reduced. On the other hand, if the amount of the liquefied gas is more than 95% by weight, the aerosol preparation does not form a sherbet-like solid when sprayed, and therefore the durable cooling effect cannot be easily obtained.

When the conditions for which the aerosol preparation of the present invention forms a sherbet-like solid are distinguished between the concentrate and the propellant of the aerosol preparation, it is necessary to contain at least 6% by weight of the lower alcohol having 1 to 3 carbon atoms in the concentrate, at least 1% by weight of the higher alcohol having at least 12 carbon atoms in the concentrate and 0.5 to 20 parts by weight of the liquefied gas based on 1 part by weight of the concentrate.

The aerosol preparation of the present invention can be prepared by dissolving the lower alcohol and the higher alcohol to give a homogeneous system, and if desired, adding such other components that do not destroy the homogeneous system, and filling the resulting concentrate together with the liquefied gas into an aerosol container. Examples of the aerosol container include containers made of metals or plastics as used usually. In view of the durable cooling effect, it is preferable to contain a suitable amount of water as such another component that does not destroy the homogeneous system. In case of addition of water to the concentrate, not more than 90% by weight of water can be added based on the total amount of the concentrate, but preferably 20 to 60% by weight of water is added to the concentrate in view of easy preparation design.

In order to enhance the calming effect on pain and itch on the affected part, the aerosol preparation of the present invention can contain such drug-effective ingredients that do not degrade the effect of the present invention, for example, anti-inflammatory and analgesic agents (e.g. indomethacin, methyl salicylate, monoglycol salicylate, ketoprofen, flurbiprofen, piroxicam, diclofenac, ibuprofen, mephenamic acid, dexamethasone acetate, etc.), antipruritics (e.g. crotamiton, ichthammol, mochthamol, thymol acid, etc.), antifungal agents (e.g. amorolfin hydrochloride, undecylenic acid, pentachlorophenol, clotrimazole, tolnaftate, trichomycin, miconazole nitrate, lanoconazole, sulconazole nitrate, oxyconazole nitrate, bifonazole, etc.), anti-histaminic agents (e.g. diphenhydramine, diphenhydramine hydrochloride, isothipendyl hydrochloride, etc.), local anesthetics (e.g. lidocaine, dibucaine hydrochloride, etc.), antibiotics (e.g. potassium iodide, chlorohexidine gluconate, acrinol, benzalkonium chloride, etc.), antiphlogistics (e.g. penicillin, tetracycline hydrochloride, fradiomycin, kanamycin, etc.), refrigerants (e.g. 1-menthol, camphor, mentha oil, etc.), and the like. The amounts of these drug-effective components are different individually, but preferably 0.001 to 10% by weight based on the total amount of the preparation.

The aerosol preparation of the present invention can contain, if necessary, any additives usable for ordinary aerosol preparations as long as they do not degrade the effect of the present invention, for example, anti-oxidants (e.g. dibutylhydroxytoluene, etc.), percutaneous absorption promoters (e.g. glycerin esters of fatty acid, fats, aliphatic carboxylates, nicotinates, azone, alkyleneglycol esters of fatty acid, etc.), perfumes, dyes and the like.

Claim 1 of 5 Claims

What is claimed is:

1. An aerosol preparation which when sprayed forms a sherbet-like solid, which comprises:

(A) a concentrate containing:

0. 3 to 65% by weight, based on the total amount of the preparation, of a lower alcohol having 1 to 3 carbon atoms; and

0.005 to 14% by weight, based on the total amount of the preparation, of a higher alcohol having at least 12 carbon atoms, and

(B) a propellant containing 50 to 85% by weight, based on the total amount of the preparation, of dimethyl ether.

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