DE3434886A1 - Stabilisers for alkyl halides and their use in aerosol preparations - Google Patents

Abstract

Use of dodecyl gallate, beta -carotene or ethylene carbonate as stabiliser or corrosion inhibitor in aerosol preparations based on alkyl halides. The abovementioned stabilisers prevent the hydrolysis occurring in the presence of water of alkyl halides (halocarbons or halogenated hydrocarbons) and the associated corrosion of the aerosol containers.

Description

Stabilizers for alkyl halides and their uses

dung in aerosol preparations The present patent application relates to the stabilization of halocarbons and halocarbons against long-term decomposition in aerosol containers.

Particularly suitable alkyl halides are those in the closed Aerosol containers are liquid at room temperature under their own pressure.

The main propellants or solvents currently used are halocarbons, such as trichloromonofluoromethane, dichlorodifluoromethane and 1,2-dichlorotetrafluoroethane Use. A frequently used solvent in aerosol preparations is also Methylene chloride.

When using aqueous aerosol compositions in aerosol containers from galvanized sheet steel or aluminum it comes to a more or less slowly ongoing hydrolysis of the alkyl halides with the formation of hydrogen halides. This leads to corrosion of the metal on the inner walls of the aerosol container. Further the resulting metal salts have a negative influence on the odor of each contained perfume oils. Hydrogen halide continues with many in the aerosol composition chemical reactions and open it useless this way.

The complete replacement of the alkyl halides by halogen-free propellants, such as propane and butane, in addition to solubility problems, lead to an increased Flammability of the preparations.

As a result of the entry into force of TRG 300 and similar regulations in the area of the European Community, the above-mentioned alkyl halides used in larger quantities to reduce flammability and therefore represent pose a significant risk of corrosion.

For these reasons, numerous attempts have been made in the past undertaken to reduce the susceptibility of the alkyl halides to hydrolysis by stabilization to reduce.

At the same time, attempts have been made to reduce corrosion by adding corrosion inhibitors to suppress or prevent. An effective combination that also complies with the ingredient legislations fair has not yet been found.

There was therefore the task of preventing the alkyl halides from hydrolysis to stabilize and at the same time to find an effective corrosion inhibitor.

It has been found in our experiments that with a single Substance is to prevent both hydrolysis and corrosion, and thus a negative odor impairment of the perfume oil or the change in others Components of the aerosol composition can be avoided.

The object is achieved through the use of dodecyl gallate, , ß-carotene or ethylene carbonate as a stabilizer or corrosion inhibitor in aerosol preparations based on alkyl halides.

The above-mentioned stabilizers or corrosion inhibitors, of which the dodecyl gallate is particularly preferred, should be in the aerosol preparations in an amount of 0.001 to 1.0 wt.%, Preferably 0.05 to 0.5 wt.% Use Find.

The invention also relates to stabilized aerosol compositions based on alkyl halides as blowing agents and / or solvents as well With a content of 0.001 to 1.0% by weight of a stabilizer or corrosion inhibitor, characterized in that the stabilizer or corrosion inhibitor is selected is made from dodecyl gallate, ß-carotene and ethylene carbonate.

The aerosol compositions according to the invention preferably contain at least traces of water and in particular have the following composition: 5.0 to 90.0% by weight alkyl halides 0.1 to 25.0% by weight water 0.1 to 35.0% by weight Active ingredients 0 to 70.0% by weight halogen-free propellants 0 to 75.0% by weight organic Solvent 0.001 to 1.0 wt.% Stabilizer, selected from gallic acid dodecyl ester ß-carotene and and ethylene carbonate 100.0% by weight Of the as a solvent and / or Propellants contained in the present aerosol compositions are in particular halocarbons, such as trichloromonofluoromethane (CCl3F) Dichlorodifluoromethane (CCl2F2), trichlorotrifluoroethane (C2Cl3F3) and 1,2-dichlorotetrafluoroethane (CClF-CClF2), as well as halogenated hydrocarbons such as dichloromonofluoromethane (CHCl2F), monochlorodifluoromethane (CHClF2), 1,2-difluoroethane (CH2F-CH2F), monochloro-1,2-difluoroethane (CHClF-CH2F), 1,1, 1-trichloroethane (CC13-CH3) and methylene chloride (CCl2H2) should be mentioned.

The aerosol compositions contain as an active ingredient any for Aerosol preparations common active ingredients.

The term “active ingredient” in the present application is intended to mean Substances are understood that are not gaseous or liquid alkyl halides, halogen-free propellants, organic solvents or as a stabilizer which are, however, a necessary part of aerosol compositions are. Examples are perfumes, dyes, deodorants, fungicides, bactericides, Insecticides and resins. The active ingredients should preferably be cosmetic Active ingredients, e.g. resins suitable for hairsprays such as copolymers of vinyl acetate and Crotonic acid, polyvinylpyrrolidone, vinylpyrrolidone-vinyl acetate copolymers, polyacrylic acid, Polymethacrylic acid, acrylic acid-methacrylic acid copolymers, also UV filter substances for sun protection sprays or cosmetic dyes that are absorbed directly onto the hair such as aromatic nitro dyes, azo dyes, anthraquinone dyes and Triphenylmethane dyes, continue to act against dandruff, perfume oils and others. If the When the aerosol composition is a hairspray, the cosmetic resin is in it Contained in an amount of about 0.5 to 4% by weight.

The aerosol compositions according to the invention can also contain up to Contains 70% by weight of a halogen-free propellant. As a halogen-free propellant mainly the gases C02, N20 and N2 as well as dimethyl ether, n-propane, n-butane and i-butane into consideration.

If necessary, the aerosol compositions can also organic solvents, e.g.

Isopropanol, ethanol or acetone, in an amount of up to 75% by weight contain.

The aerosol compositions described above are also at Extremely stable over long periods of storage and does not cause corrosion of the aerosol container.

The following examples are intended to illustrate the subject matter of the invention in greater detail explain.

Example 1 Hairspray 20.00 g trichloromonofluoromethane 35.00 g methylene chloride 1.00 g water 2.00 g copolymer of vinyl pyrrolidone and vinyl acetate (50:50) 0.20 g of perfume oil 21.79 g mixture of n-propane / n-butane in a ratio 60: 40 10.00 g isopropanol 10.00 g acetone 0.01 g gallic acid dodecyl ester 100.00 In each case, samples of the above composition were placed in aerosol containers made of tinplate (Tin plating El, welded, without seam covering by lacquer) or in aluminum monoblock boxes filled with a phenolic resin interior protective varnish and stored at temperatures of 200C resp. 400C together with blank samples of the same composition but without dodecyl gallate stored. The opened blank samples already showed 0 after a storage time of 6 months at both 40 ° C storage temperature and 200C storage temperature extensive attack on the tin coating and a clearly perceptible change in odor of the perfume oil used. After a year of storage, the composition has changed of the blank samples clearly discolored and show the inner walls of the aerosol containers severe corrosion. In the case of the aerosol composition according to Example 1, however, is even after 12 months of storage neither a change in the ingredients nor a Determine corrosion of the aerosol container.

Example 2 Hairspray 20.0 g trichloromonofluoromethane 35.0 g methylene chloride 1.5 g of water 2.0 g copolymer of vinyl pyrrolidone and vinyl acetate (50: 50) 0.3 g perfume oil 21.1 g mixture of n-propane / n-butane in a ratio of 60: 40 10.0 g isopropanol 10.0 g acetone 0.1 g β-carotene or ethylene carbonate 100.0 g

Claims (10)

Claims 1 * Use of gallic acid dodecyl ester, I3-carotene or ethylene carbonate as a stabilizer or corrosion inhibitor in aerosol preparations based on alkyl halides. 2. Use according to claim 1, characterized in that the Alkyl halides are selected from methylene chloride, 1,1,1-trichloroethane and trichloromonofluoromethane. 3. Use according to claim 1 and 2, characterized in that that the stabilizer or corrosion inhibitor in an amount of 0.001 to 1.0 wt.% is used. 4. Stabilized aerosol composition based on alkyl halides as a propellant and / or solvent and with a content of 0.001 to 1.0 % By weight of a stabilizer or Corrosion inhibitor, characterized in that the stabilizer or corrosion inhibitor is selected from dodecyl gallate, p-carotene and Ethylene carbonate. 5. Aerosol composition according to claim 4, characterized in that that the stabilizer resp. Corrosion inhibitor is dodecyl gallate. 6. aerosol compositions according to claim 4 and 5, characterized in that that it contains 0.1 to 25% by weight of water. 7. aerosol composition according to claim 4 to 6, characterized in that that the alkyl halides are contained in an amount of 5 to 89.3% by weight. 8. Aerosol composition according to claim 4 to 7, characterized in that that the alkyl halides are selected from methylene chloride, l, l, l-trichloroethane and trichloromonofluoromethane. 9. Aerosol composition according to claim 4 to 8, consisting of 5.0 - 90.0% by weight alkyl halide 0.1-25.0% by weight water 0.1-35.0% by weight active ingredients 0-70.0% by weight halogen-free propellants 0-75.0% by weight organic solvents 0.001-1.0% by weight stabilizer, selected from dodecyl gallate, ~ ß-carotene and ethylene carbonate 100.0% by weight 10. Aerosol composition according to claim 4 bis 9, characterized in that it is a hairspray.