JPH0410918B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a powdered aerosol composition for application to the human body. Conventionally, aerosol products applied to the human body include:
In order to improve the effect of the active ingredient, which is the base ingredient, and to improve the feeling of use, it has been considered desirable to include powder components. For example, aerosol products used as antiperspirants have a powder component as an essential ingredient, and aerosol products used as insect repellents and foot sprays require retention of the active ingredient on the skin surface or the feeling of use. It is desired to blend various powder components for the purpose of improvement. In addition, various aerosol products such as anti-inflammatory agents, disinfectants, and athlete's foot medicines have been developed by blending powder components into aerosols for application to the human body. These powder components mainly have an average particle diameter of 1 μm because they provide uniform sprayability, good powder redispersibility, and less clogging of the injection holes in the aerosol container. A very fine powder is used. However, it has been pointed out that when an aerosol composition containing a powder component with such a small particle size is applied to the human skin surface, there is a risk of inhaling the powder dispersed with exhalation. According to Paul E. Palm, Theodore Hatch, et al. (1956), the particle size that most easily deposits in the lungs is about 1 μm in diameter, and Murayama (1968) reported that after 3 minutes after spraying, mist with an average particle size of 3 to 5 μm is is floating in the air, indicating a high possibility of inhalation. The human lungs communicate with the mouth and nose through the trachea.
Inside the lungs, the trachea further branches into bronchi and bronchioles, which reach the alveoli. In general, the trachea and bronchi have a larger cross-sectional diameter than the bronchioles, and these epithelial cells are equipped with cilia that trap inhaled powder and expel it from the body, preventing it from being inhaled into the alveoli. . In particular, it has been reported that particles larger than 10 μm do not enter the lungs because they are 100% trapped by hair and deposits in the nasal cavity [GW
Cambridge (1973)]. Furthermore, it is known that when a powder aerosol for human body application is applied to the human skin surface, there are almost no spray particles larger than 5μ above the injection position, regardless of the internal pressure of the spray, the type of propellant, the shape of the injection nozzle, etc. [Murayama et al. (1968)]. Therefore, in consideration of such knowledge, it is considered that powder components for powder aerosol for application to the human body should have an average particle size of 5μ or more, preferably 10μ or more, but the powder used When the particles become large, the sedimentation speed after redispersion becomes faster, the jetting properties become uneven, and the nozzle is more likely to become clogged, making it difficult to produce good aerosol products. . Therefore, as a result of intensive research in order to overcome such difficulties, the present inventors combined the active ingredient and a powder component with an average particle size of 5 to 45μ into n-pentane and/or iso-pentane.
When mixed and dispersed in pentane and a propellant to form an aerosol composition, the powder component is uniformly dispersed in the composition despite its large average particle size, and also has excellent redispersibility during use. When it is filled in an aerosol container and applied to the skin, it can be applied evenly, has good drying properties and is less sticky, and has an excellent feeling of use.It is also effective because the active ingredients are retained on the skin for a long time. target,
Furthermore, the present invention was completed based on the discovery that a powdered aerosol composition for application to the human body can be obtained without fear of inhalation into the lungs, since the average particle size of the sprayed mist exceeds 5μ. That is, in the present invention, the active ingredient is 0.5 to 20% by weight,
1 to 30% by weight of a powder component with an average particle size of 5 to 45μ,
1 to 80% by weight of n-pentane and/or iso-pentane and 10 to 95% by weight of propellant (hereinafter expressed in %)
The present invention provides a powder aerosol composition for application to the human body containing the following. As the powder components used in the powder aerosol composition for application to the human body of the present invention, those conventionally used for this type of application can be used as long as the average particle size is between 5 and 45 μm. Specific examples include: Aluminum, kaolin, talc, aluminum chlorohydroxide, titanium oxide, magnesium carbonate, magnesium silicate, fish scale foil, mica titanium,
mica, starch, synthetic polymer substances (nylon,
(polyethylene, etc.), magnesium salts, calcium salts, or aluminum salts of stearic acid, iron oxides such as red iron oxide, and bentonite powders, and these may be used alone or in combination of two or more. Considering inhalation toxicity, these powder components need to have an average particle diameter of 5μ or more; if it exceeds 45μ, roughness will appear on the skin surface to which it is applied, resulting in a poor feeling of use. This powder component accounts for 1 to 30% of the total composition, preferably 3 to 30%.
Contains 13%. N-pentane and/or iso-pentane is blended in an amount of 1 to 80%, preferably 5 to 30%, based on the total composition. As propellants, those commonly used in such cases can be used, including dichlorodifluoromethane (Freon 12), trichloromonofluoromethane (Freon 11), dichlorotetrafluoroethane (Freon 114), and liquefied petroleum. Gas, dimethyl ether, etc. can be mentioned. These can be used alone or as a mixture of two or more, and account for 10 to 95%, preferably 70 to 90% of the total composition.
It is blended. The powder aerosol composition for human body application of the present invention includes:
By appropriately selecting the active ingredient blended as the main ingredient, it can be used for various purposes such as antiperspirants, pest repellents, and fungicides. As active ingredients, antiperspirants include aluminum hydroxychloride, pest repellents include N,N-diethyltoluamide, dimethyl phthalate, dibutyl phthalate, and 2,3,4,5-bis(△ ₂ -butylene). -tetrahydrofurfural, di-n-propylisocincomeronate, di-m-butylsuccinate, and the fungicides include isopropylmethylphenol, benzalkonium chloride, trichlorohydroxydiphenyl ether, and the like. These can be used alone or in combination of two or more, and the blending amount varies depending on the type of active ingredient, but is preferably 0.5 to 20% of the total composition. In addition to the above-mentioned essential ingredients, the powder aerosol for application to the human body of the present invention includes isopropyl myristate, isopropyl palmitate, isopropyl stearate, to increase the adhesion of the powder to the skin surface to which it is applied.
Oil agents such as butyl stearate and dimethylpolysiloxane: Alcohols such as ethyl alcohol and isopropyl alcohol to enhance the cooling sensation; Sorbitan monolaurate and polyoxyethylene to improve the dispersibility of powder components in solvents and propellants One or more of surfactants such as sorbitan monolaureate and polyoxyethylene sorbitan trioleate; emollients such as avocado oil, lanolin alcohol, jojoba oil, liquid paraffin, and squalane; or fragrances, etc. can be added. . The powder aerosol composition for human body application of the present invention includes:
It can be filled into an aerosol container and applied to the skin, etc. When the powdered aerosol composition for human body application filled in an aerosol container is shaken before use, the active ingredient and the powdered component are well redispersed in n-pentane and/or iso-pentane and the propellant, and the dispersion is maintained. Since it is retained for a long time, it can be applied uniformly to the skin without clogging the injection holes, and can exhibit excellent effects. In addition, by using a powder component with an average particle size of 5 to 45 μm, problems of inhalation toxicity of the powder component are less likely to occur, and there is less discomfort. Further, due to the action of the highly volatile solvent, it has various advantages such as good drying properties, no stickiness, no staining of clothes, etc. Next, an example will be given and explained. Example 1 Antiperspirants, pest repellents, and fungicides having the compositions shown in Table 1 below were prepared, and their redispersibility, clogging of injection holes, and usability were examined. The results are shown in Table 2. (Redispersibility test) After each aerosol composition was left at a temperature of 45° C. for 6 months, the dispersion state of the powder was evaluated according to the following criteria. Uniformly dispersed 〇 A slight tendency to agglomeration is observed △ Strong agglomeration occurs in some areas × (Clogging of injection holes and feeling of use) Each aerosol composition was stored at a temperature of 45°C for 7 days. Injection was carried out at intervals, and the presence or absence of clogging and the feeling of use were examined.

【table】

[Table] Example 2 A powder aerosol composition for application to the human body was prepared using talc powder with an average particle size of 1μ or 10μ, and the particle size after spraying was measured using the following measurement method. The results are shown in Table 3 and Figure 2. (Composition) N,N-diethyltoluamide 3 (%) n-pentane 15 Dimethylpolysiloxane 2 Talc 10.0 Fragrance Trace amount Propellant 70.0 (Measurement method) Assemble the Andersen sampler device shown in Figure 1, and set the flow rate to 29.3/2. After setting the time to 30 minutes, spray about 5 g of the above aerosol composition from the spray inlet, and
Sampling was performed for minutes. After sampling, the collection plates and backup filters were stored in a desiccator containing a desiccant for about a day and night, and then their weight was measured to examine the distribution of particles collected on each collection plate.

【table】

[Table] Example 3 The aerosol compositions of Invention 1, Invention 2, and Comparative Product 1 in Example 1 were filled into an aerosol container, and applied to the upper arm of a healthy adult male per 1 cm ² of insect repellent. After spraying so that the amount is 0.2 mg, 2
Approximately 50 female adult Aedes albopictus mosquitoes that had not taken blood were inserted into the cage for 2 minutes at regular intervals, and the number of mosquitoes that had taken blood was observed. The results are shown in Table 4.

[Table] * 1 minute insertion

[Brief explanation of drawings]

Figure 1 is a diagram showing the configuration of the Andersen sampler, and Figure 2 is a diagram showing the particle size distribution of particles during injection, when talc powder with an average particle size of 1μ is used as the powder component (...) and 10μ. The result is (-) when the powder is used. A _s : Andersen sampler, FM: Float area flowmeter (flow meter), V: flow rate adjustment valve, F: filter, R: rotary compressor, Sr: silencer, I: spray inlet, C _H : Simple chamber, diameter 15cm, height 30cm.

Claims (1)

[Claims] 1 Active ingredient 0.5-20% by weight, average particle size 5-20% by weight
Powdered aerosol composition for human body application containing 1 to 30% by weight of a 45μ powder component, 1 to 80% by weight of n-pentane and/or iso-pentane and 10 to 95% by weight of propellant.