DE2608226A1 - AGENTS WITH PHYSIOLOGICAL COOLING EFFECT - Google Patents

Description

HAARMANN & REIMER

■ l '

B / Kp / Pf

Means with a physiological cooling effect

The invention relates to agents with a physiological cooling effect on the skin and mucous membranes of the body.

Menthol, the main ingredient in peppermint oils, is characterized by its excellent cooling effect on the skin and mucous membranes of the body. Its cooling effect is not based on:? a latent heat of vaporization, but arises from the direct action of the compound on the nerve endings of cold receptors. However, the smell and taste properties of menthol limit its use or, in some cases, even make it impossible. The smell of peppermint is too specific and too pungent for various areas of application and irritates tears and the mucous membrane of the sole. For other applications, the taste too sharp and bitter is. The great volatility of menthol often has a disadvantageous effect.

There has therefore been no lack of attempts to find substances which have the positive effect of cooling without having the disadvantages of menthol described above. Thus, for example, in DT-OS-p-menthane-3-carboxamide 2,202,535 and esters of p-menthane-3-carboxylic acid, in the DT-OS 2205255 N-substituted p-methane-3-carboxamides in which DT-OS 2,317,538 substituted amides, in DT-OS 2,334,985 cyclic and acyclic sulfoxides

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and sulfones and phosphine oxides substituted in DT-OS 2,345,156 suggested.

The compounds that meet the set goal of having a cooling effect while being odorless and tasteless, in part come very close, however, have the disadvantage that they are neither naturally occurring substances nor of human nature Organism can be broken down into naturally occurring substances. They are therefore physiological and food law dubious. In addition, they are sometimes very expensive because they can only be produced in multi-stage processes.

The derivatives of menthol proposed so far, which either occur naturally or are broken down by the organism to form naturally occurring substances, only incompletely meet the requirements placed on them. For example, the 1-menthyl ethyl carbonate proposed in DT-OS 2 022 364 has an orange-like odor, the N-acetylglycine menthyl ester proposed in DT-OS 2 433 165 and the menthol esters of heterocyclic carboxylic acids proposed in DT-OS 2 339 661 are bitter and the menthyl ketoesters proposed in U.S. Patent 3,830 are e.g. T. persistently bitter and do not have the desired cooling effect.

It has now been found, surprisingly, that esters of menthol and naturally occurring hydroxycarboxylic acids with 2 to 6 carbon atoms, which are optionally esterified on the hydroxyl group of the carboxylic acid, are odorless and tasteless and have an excellent, especially long-lasting cooling effect.

The invention therefore relates to agents with a physiological cooling effect on the skin and mucous membranes of the body that this causes

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are characterized in that they are esters of menthol and naturally occurring hydroxycarboxylic acids with 2 to 6 carbon atoms, the are optionally in turn esterified on the hydroxyl group with 1 to 4 carbon atoms containing carboxylic acids.

Examples of naturally occurring hydroxycarboxylic acids with 2 to 6 carbon atoms are: glycolic acid, ß-hydroxybutyric acid, CC- Hydroxy is ovalic acid, (t-Hydroxy-ct-methylvaleric acid, (t-Hydroxy-JT-methylvaleric acid, CG-hydroxycaproic acid and ß-hydroxycaproic acid, but especially lactic acid.

As carboxylic acids having 1 to 4 carbon atoms, with which the hydroxyl group of the hydroxycarboxylic acids can be esterified, formic acid, acetic acid and propionic acid are especially mentioned.

The esters to be used according to the invention are only partly new. Of the esters described, however, it was unknown that they were one have a physiological cooling effect on the skin and mucous membranes of the body. The esters can be prepared by conventional methods , for example by acid-catalyzed esterification of menthol with hydroxycarboxylic acids or by reduction of Keto-Mementhyl Ester are in turn obtainable e.g. by transesterification of ketocarboxylic acid alkyl esters with menthol. The esterification the hydroxyl group of the hydroxycarboxylic acid with the 1 to 4 carbon atoms having carboxylic acids is expediently as last stage carried out.

The esters to be used according to the invention have asymmetric carbon atoms; optical isomerism can therefore occur in them. Depending on the starting material and the manufacturing methods used, they can be used as mixtures of the optical isomers or as pure Isomers exist. The cooling effect of the isomers can be different, so that one or the other isomer is preferred can be.

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The coolants according to the invention can be used anywhere where a physiological cooling effect is desired. Compositions in which such coolants like to be used Examples of luxury items such as chewing gum, chewing tobacco, cigarettes, beverages, ice cream, confectionery, etc., pharmaceutical preparations, personal care products or cosmetic preparations such as dentifrices, mouthwashes, gargle preparations, perfumes, powders, lotions, Ointments, oils, creams, aftershave lotions. Shampoos etc.

The end products contain the esters to be used according to the invention in an amount sufficient to protect the cold receptors to stimulate and induce the desired sensation of cold. As a rule, 0.1 to 5 percent by weight based on the weight of the total composition are used. In addition to the The esters according to the invention, in particular menthyl lactate, have an enhancing effect, i.e. a taste-enhancing effect Effect on other flavors. For example, the addition of a also allows below the threshold value for a physiological cooling effect lying amount of the invention to be used esters such as chewing gum or Amount of peppermint oil incorporated into dentists as flavorings, Spearmint oil, or other flavorings, without degrading that there is a deviation in taste.

The following examples explain the use of the coolants according to the invention in various compositions. Unless otherwise stated, the percentages are percentages by weight.

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example 1
toothpaste

The following components were mixed in the usual way:

Glycerin DAB 6 20%

p-hydroxybenzoic acid methyl ester 0.15 %

Carboxymethyl cellulose 1.2 %

Saccharin 0.2 %

Dicalcium phosphate (containing water) 48 %

Sodium Lauryl Sulphate 2.2 %

Flavors 1.0 %

Water 100 %

Before the end of the mixing process, 1 % 1-menthyl lactate was added. The toothpaste is characterized by a cooling effect.

Example 2
chewing gum

In a commercially available gum base 0.3% O-Acetylmilchsäure-1-menthyl ester were incorporated. The chewing gum mass creates a feeling of coolness in the mouth.

Example 3
fondant

1 % 1-menthyl lactate was incorporated into a commercially available fondant base. The fondant mass has a pleasantly refreshing taste.

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Example 4
Mouthwash

A mouthwash concentrate was made from the following ingredients:

Ethanol 60 %

Bromochlorophene 0.05 %

Polyoxyethylene sorbitan monolaureate 1 %

Allantoin 0.2 %

Saccharin 0.2%

Flavors to 100 %

5 % 1-menthyl lactate was added to the mixture. For the preparation of mouthwash, the concentrate was diluted with 10 times its volume of water. The mouthwash is characterized by a cooling effect.

A similarly acting mouthwash was obtained if, instead of the 5 % 1-menthyl lactate, the same amount of glycolic acid, ß-hydroxybutyric acid, <X < -hydroxyisovaleric acid, A -hydroxy-ct- methylvaleric acid-, o & -hydroxy- ^ - methylvaleric acid- , flt-hydroxycaproic acid or ß-hydroxycaproic acid 1-menthyl ester was used.

Example 5

Face cleansing lotion

A facial cleansing lotion was made from the following components:

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Ethanol 26.3 1-menthyl lactate 1 Perfume oil 0.1 Emulsifier 4th 1,2 propylene glycol 1 Allantoin 0.05 Lactic acid 0.05 water 67.5

The lotion has a cooling effect on the skin of the face.

Example 6
After shave lotion

An after-shave lotion was made from the following components:

Ethanol 55.5 %

1-menthyl lactate 1.5 %

Perfume oil 0.5 %

Emulsifier 0.3%

Water 39.8 %

Allantoin 0.2 %

1,2-propylene glycol 2 %

Lactic acid 0.2%

The lotion produces a cooling effect when applied to the face.

A similarly acting preparation was obtained; if instead of 1-menthyl lactate the same amount of 0-formyllactic acid 1-menthyl ester was used.

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Example 7
Clear shampoo

A clear shampoo is made from the following components:

Fatty acid amidoalkyl betaine 60 %

Water 35.2 %

Preservative 0.2 %

d, 1-menthyl lactate 2 %

Perfume oil 0.5%

Coconut fatty acid diethanolamide 2 %

The shampoo creates a strong cooling effect on the scalp.

Example 8
After bath freshener

An after-bath freshener was made from the following components:

Ethanol 50 1-menthyl lactate 1.5 Perfume oil 2 Lanolin-based refatting agent 2 Emulsifier 1.5 water 43

The after-bath freshener is characterized by a pleasantly refreshing effect.

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Claims (6)

Patent claims: 1. Means with a physiological cooling effect on the skin and mucous membranes of the body, characterized in that it contains esters of menthol and naturally occurring hydroxycarboxylic acids with 2 up to 6 carbon atoms, which in turn is esterified on the hydroxyl group with 1 to 4 carbon atoms containing carboxylic acids included. 2. Means according to claim 1, containing as a cooling reagent Menthyl lactate. 3. Use of esters from menthol and naturally occurring hydroxycarboxylic acids with 2 to 6 carbon atoms, which may be are in turn esterified on the hydroxyl group with 1 to 4 carbon atoms having carboxylic acids, as agents physiological cooling effect on the skin and mucous membranes of the body. 4. Use of menthyl lactate according to claim 3. 5. Coolant-containing compositions characterized by a content of coolants according to Claims 1 and 2. 6. Coolant- containing compositions according to claim 5, characterized in that they contain the coolant according to claim 1 and 2 in an amount of 0.1 to 5 percent by weight based on the weight of the preparation. HR 62 - 9 - 709836/0088 ORIGINAL INSPECTED