External preparation for the skin

Abstract

A skin treatment composition that characteristically contains alkylene polyglycol dineopentanoate having a specific structure. The object is to provide a skin treatment composition that gives a refreshing sensation at the time of application and contains an oil component that is highly safe with low skin irritation. The skin treatment composition specifically contains diethyleneglycol dineopentanoate, triethyleneglycol dineopentanoate, tetraethyleneglycol dineopentanoate, dipropyleneglycol dineopentanoate, tripropyleneglycol dineopentanoate, etc. Dipropyleneglycol dineopentanoate and tripropyleneglycol dineopentanoate are particularly preferable in terms of the sensation at the time of application; they provide a skin treatment composition that is particularly superior in absorption into the skin and a sensation of permeation and highly safe.

1 . A skin treatment composition that characteristically contains an alkylene polyglycol dineopentanoate represented by the following general formula (1):  
       
         
           
           
               
               
           
         
         (In this formula, m denotes an integer 2-4, and n denotes an integer 2-3.)  
       
     
     
         2 . The skin treatment composition of  claim 1  wherein the compound represented by formula (1) is tripropyleneglycol dineopentanoate.  
     
     
         3 . Tripropyleneglycol dineopentanoate represented by general formula (2) as follows:  
       
         
           
           
               
               
           
         
       
     
     
         4 . The skin treatment composition of  claim 2 , wherein the treatment composition is an emulsion, and a blend ratio of the alkylene polyglycol dineopentanoate therein is 0.001-50.0% (mass percentage) of the total composition.  
     
     
         5 . The skin treatment composition of  claim 2 , wherein the treatment composition is an emulsion, and a blend ratio of the alkylene polyglycol dineopentanoate therein is 0.1-30.0% (mass percentage) of the total composition.  
     
     
         6 . The skin treatment composition of  claim 1 , further comprising one or more selected from the group consisting of a powder, liquid fats and oils, solid fats and oils, waxes, hydrocarbons, higher fatty acids, higher alcohols, esters, silicones, anionic surfactants, cationic surfactants, ampholytic surfactants, nonionic surfactants, humectants, water-soluble polymers, thickeners, coating agents, ultraviolet absorbents, sequestering agents, lower alcohols, polyhydric alcohols, sugars, amino acids, organic amines, polymer emulsions, pH adjusting agents, skin nutrients, vitamins, antioxidants, antioxidation assistants, perfumes, and water.  
     
     
         7 . The skin treatment composition of  claim 2 , further comprising one or more selected from the group consisting of a powder, liquid fats and oils, solid fats and oils, waxes, hydrocarbons, higher fatty acids, higher alcohols, esters, silicones, anionic surfactants, cationic surfactants, ampholytic surfactants, nonionic surfactants, humectants, water-soluble polymers, thickeners, coating agents, ultraviolet absorbents, sequestering agents, lower alcohols, polyhydric alcohols, sugars, amino acids, organic amines, polymer emulsions, pH adjusting agents, skin nutrients, vitamins, antioxidants, antioxidation assistants, perfumes, and water.  
     
     
         8 . A method of treating skin comprising applying to the skin the composition of  claim 1 .  
     
     
         9 . A method of treating skin comprising applying to the skin the composition of  claim 2 .  
     
     
         10 . A method of producing alkylene polyglycol dineopentanoate of Formula (1):  
       
         
           
           
               
               
           
         
         wherein m denotes an integer 2-4, and n denotes an integer 2-3, comprising reacting pivaloyl chloride with polyethylene glycol according to the reaction scheme as follows:  
         
           
             
             
                 
                 
             
           
         
       
     
     
         11 . The method of  claim 10 , wherein resultant reaction solution is rinsed with ammonium chloride and then extracted with ethyl acetate to form a resultant extract solution.  
     
     
         12 . The method of  claim 11 , wherein the resultant extract solution is concentrated and purified by column chromatography.