Method for manufacturing pure guar meal

Abstract

A method for producing pure guar meal and the use of hydroxy propyl trimethyl ammoniium chloride-guar meal obtained according to the method in clear aqueous cosmetic formulations which are intended to be applied on hair and/or skin and which can be washed out or rinsed off as conditioning agents or depositing agents to dilute cosmetic formulations.

1 . A process for the production of pure guar meal, wherein the following steps are involved: 
 (a) treatment of the guar split with an alkaline solution in the presence of hydrogen peroxide at 65 to 70° C.;    (b) partial neutralization of the alkaline split with an organic or inorganic acid;    (c) mechanical removal of the peripheral cells layers of the guar split;    (d) treatment of the split with an aqueous alcohol solution; and    (e) grinding of the split into meal.    
     
     
         2 . A process according to    claim 1   , wherein the alkaline solution employed in step (a) is caustic soda, preferably in a concentration of 25 to 50% by weight, most preferably in a concentration of 33% by weight, and in a quantity of 6-10%, as based on the starting material.  
     
     
         3 . A process according to    claim 1    or    2   , wherein the quantity of hydrogen peroxide used in step (a) is 0.175 to 0.35% by weight, most preferably 0.175% by weight, and a hydrogen peroxide solution of 35% by weight is employed.  
     
     
         4 . A process according to one of the preceding claims, wherein the acid in step (b) is sulfuric acid, phosphoric acid, or another suitable organic acid, preferably acetic acid.  
     
     
         5 . A process according to    claim 4   , wherein the sulfuric acid used in step (b) is employed in a concentration of 60 to 80% by weight, preferably 70% by weight.  
     
     
         6 . A process according to    claim 4   , wherein the phosphoric acid used in step (b) is employed in a concentration of 60 to 85% by weight, preferably 75% by weight.  
     
     
         7 . A process according to one of the preceding claims, wherein the alcohol solution employed in step (d) is an aqueous solution of ethanol, methanol, or, preferably, isopropanol.  
     
     
         8 . A process according to one of the preceding claims, wherein the aqueous alcohol solution is preferably a 20 to 40% by weight isopropanol solution, most preferably 25% by weight.  
     
     
         9 . A process according to    claim 7    or    8   , wherein the splits, after removal of the peripheral cell layers in step (c) and before treatment with an aqueous isopropanol solution in the presence of a lye, preferably caustic soda, at 60 to 70° C., in step (d) are washed twice with water.  
     
     
         10 . Pure guar meal according to one of the preceding claims, wherein said guar meal is subjected to a derivatization by means of carboxy methylation, hydroxy propylation, or cationization, or combinations thereof.  
     
     
         11 . Guar meal which, as a 1% aqueous solution, has a viscosity of up to 9000 mPas and a content of proteins and materials that cannot be hydrolized by acid of 0.8 to 1.2% and which, as a 0.5% aqueous solution, exhibits a transparency of at least 80% measured at a wavelength of 500 nm, produced with the process according to one of the preceding claims.  
     
     
         12 . Guar meal according to    claim 10   , wherein the transparency of a 0.5% solution of these derivatives measured at a wavelength of 500 nm extends up to 98%.  
     
     
         13 . Guar meal according to one of claims  10 ,  11 , and  12 , for use as a thickening agent for foodstuffs, cosmetics, pharmaceutical products, for pigments and lacquers, for textile pigments, for crude oil extraction, and for explosive substances.  
     
     
         14 . Hydroxypropyltrimethyl ammonium chloride guar meal, that is obtained by etherizing guar meal obtained with the process according to one of    claims 1    to    9    with 2, 3 epoxypropyltrimethyl ammonium chloride as a cationic etherizing agent, under basic conditions and in an inert gas atmosphere, followed by purification and separation.  
     
     
         15 . Hydroxypropyltrimethyl ammonium chloride guar meal according to    claim 14   , wherein etherization is performed in two primary steps: 
 an initial step, in which the cationic etherizing agent is diffused in the guar flower, under alkaline conditions and in an inert gas atmosphere at a temperature from 20 to 55° C., preferably 30 to 50° C., and is then suspended in an aqueous alcohol solution, particularly a water-isopropanol solution containing 25 to 70% by weight isopropanol, and a second step, in which the actual etherization is performed in an inert gas atmosphere at a temperature of 50 to 70° C., most preferably at a temperature of 60 to 65° C.    
     
     
         16 . The use of a hydroxypropyltrimethyl ammonium chloride guar meal according to    claim 14    or    15    in clear, aqueous cosmetic formulations which are intended for application on the hair and/or skin and are to be rinsed away, as a conditioner and/or as a depositing agent for further conditioning agents in diluting the cosmetic formulation.  
     
     
         17 . Use according to    claim 16   , wherein these cosmetic formulations contain 0.05 to 0.5%, preferably 0.1 to 0.3% hydroxypropyltrimethyl ammonium chloride guar meal and at least 60% by weight water and exhibit a permeability of at least 92% measured at 600 nanometers.  
     
     
         18 . Use according to    claim 16    or    17   , wherein these clear cosmetic formulations also contain a non-volatile silicon in the form of particles with a diameters of less than 35 nanometers, preferably 20 to 25 nanometers.  
     
     
         19 . Use according to    claim 18   , wherein the silicon is present in a quantity of 0.1 to 1% by weight, preferably 0.5 to 1% by weight, expressed as active ingredient, relative to the weight of the cosmetic formulations.  
     
     
         20 . Clear, aqueous cosmetic formulations which are intended for use on the hair and/or skin and are to be rinsed away and which contain the following ingredients, relative to their weight 
 8 to 30% by weight, preferably 10 to 20% by weight, at least, of a non-ionic, anionic, amphoteric, or dipolar surfactant, expressed as active ingredient,    0.05 to 0.5% by weight, preferably 0.1 to 0.3% by weight, hydroxypropyltrimethyl ammonium chloride guar meal according to    claim 14    or    15   ,    when so required, 0.1 to 1% by weight, preferably 0.5 to 1% by weight, at least, of a non-volatile silicon in an aqueous emulsion, whose particle size is less than 35 nanometers, preferably about 20 to about 25 nanometers, expressed as active ingredient,    and at least 60% by weight water, preferably at least 75% by weight.    
     
     
         21 . Use according to one of    claims 16    to    19   , or of cosmetic formulations according to    claim 20   , wherein the hydroxypropyltrimethyl ammonium chloride guar meal exhibits a substitution degree of about 0.01 to about 0.4, preferably 0.05 to 0.25, and a molecular weight of 50,000 to 3·10 6 .  
     
     
         22 . Use according to one of    claims 16    to    19   , as well as  20 , or of cosmetic formulations according to    claim 20    or    21   , wherein these clear, aqueous formulations exhibit a permeability of at least 92% measured at 600 nanometers.  
     
     
         23 . Use according to one of    claims 16    to    19   , or  22 , or of cosmetic formulations according to one of    claims 20    to    22   , wherein these clear cosmetic formulations are present in the form of a conditioning shampoo, a shower gel, or a liquid soap.