Hair-Treating Agent And Methods Of Treating Hair

Abstract

A hair processing composition contains an alkoxysilane (1); an organic acid; and water and has a pH in a range of from 2 to 5. A method for processing hair includes mixing while stirring the above-described hair processing composition and allowing a silanol compound (2) produced through hydrolysis of the alkoxysilane (1) represented by general formula (1) to penetrate into the hair. A method for processing hair further includes applying to hair an acidic aqueous solution or an alkaline aqueous solution after the silanol compound (2) has penetrated into the hair to accelerate the polymerization of the silanol compound. R 1 p Si(OR 2 ) 4−p   (1) R 1 p Si(OH) n (OR 2 ) 4−p−n   (2) wherein R 1 and R 2 represent a C 1 -C 6 alkyl group or a C 2 -C 6 alkenyl group, p represents an integer of from 0 to 3, and n represents an integer of not less than 1 and not more than (4−p).

1 . A hair processing composition comprising an alkoxysilane represented by the following formula (1):  
       R 1   p Si(OR 2 ) 4−p    (1)  
     wherein R 1  and R 2  represent a straight or branched alkyl group having 1 to 6 carbon atoms or a straight or branched alkenyl group having 2 to 6 carbon atoms, p″R 1 ″(s) and (4−p)″R 2 ″(s) may be the same or different, and p represents an integer of from 0 to 3; an organic acid; and water, wherein the composition has a pH in a range of from 2 to 5.  
   
   
       2 . The hair processing composition according to  claim 1 , which is composed of a first agent comprising the alkoxysilane represented by general formula (1) and a second agent comprising the organic acid and water, wherein the composition has a pH in a range of from 2 to 5.  
   
   
       3 . The hair processing composition according to  claim 1 , wherein the organic acid is an organic acid having a first dissociation index (pKa1) in a range of from 1.9 to 5.0.  
   
   
       4 . The hair processing composition according to  claim 1 , wherein the content of water in the whole composition is 20 to 95% by weight.  
   
   
       5 . The hair processing composition according to  claim 1 , further comprising a surfactant.  
   
   
       6 . The hair processing composition according to  claim 5 , wherein the surfactant is a nonionic surfactant having an HLB in a range of from 9 to 15.  
   
   
       7 . A method for processing hair, which comprises mixing while stirring the hair processing composition according to any of  claims 1  to  6 , and applying the composition to hair to allow a silanol compound represented by general formula (2):  
       R 1   p Si(OH) n (OR 2 ) 4−p−n    (2)  
     wherein R 1 , R 2  and p have the same meaning as above, n is an integer of not less than 1 and not more than (4−p), and p″R 1 ″(s) and (4−p−n)″R 2 ″(s) may be the same or different, and generated through the hydrolysis of the alkoxysilane represented by general formula (1), to penetrate into the hair.  
   
   
       8 . The method for processing hair according to  claim 7 , which comprises the step of heating the applied part after application of the hair processing composition to the hair.  
   
   
       9 . A method for processing hair, which comprises mixing while stirring a hair processing composition (A 1 ) comprising as constituents an alkoxysilane represented by the following formula (1):  
       R 1   p Si(OR 2 ) 4−p    (1)  
     wherein R 1  and R 2  represent a straight or branched alkyl group having 1 to 6 carbon atoms or a straight or branched alkenyl group having 2 to 6 carbon atoms, p″R 1 ″(s) and (4−p)″R 2 ″(s) may be the same or different, and p represents an integer of from 0 to 3; an organic acid; and water, applying to hair a hair processing composition (A 2 ) which is produced after the alkoxysilane is hydrolyzed and converted to a silanol compound represented by general formula (2):  
       R 1   p Si(OH) n (OR 2 ) 4−p −n    (2)  
     wherein R 1 , R 2  and p have the same meaning as above, n is an integer of not less than 1 and not more than (4−p), and p″R 1 ″(s) and (4−p−n)″R 2 ″(s) may be the same or different, and then applying as a polymerization accelerator an acidic aqueous solution (B a ) which, when mixed with the hair processing composition (A 2 ) at a weight ratio of 1:1, makes the pH of the hair processing composition (A 2 ) in a range of from 1 to 4.  
   
   
       10 . The method for processing hair according to  claim 9 , wherein the acidic aqueous solution (B a ) used as a polymerization accelerator comprises an organic or inorganic acid having a first dissociation index (pKa1) less than 4.1.  
   
   
       11 . A method for processing hair, which comprises mixing while stirring a hair processing composition (A 1 ) comprising as constituents an alkoxysilane represented by the following formula (1):  
       R 1   p Si(OR 2 ) 4−p    (1)  
     wherein R 1  and R 2 represent a straight or branched alkyl group having 1 to 6 carbon atoms or a straight or branched alkenyl group having 2 to 6 carbon atoms, p″R 1 ″(s)and (4−p)″R 2 ″(s) may be the same or different, and p represents an integer of from 0 to 3; an organic acid; and water, applying to hair a hair processing composition (A 2 ) which is produced after the alkoxysilane is hydrolyzed and converted to a silanol compound represented by general formula (2):  
       R 1   p Si(OH) n (OR 2 ) 4−p−n    (2)  
     wherein R 1 , R 2  and p have the same meaning as above, n is an integer of not less than 1 and not more than (4−p), and p″R 1 ″(s) and (4−p−n)″R 2 ″(s) may be the same or different, and then applying as a polymerization accelerator an alkaline aqueous solution (B b ) which, when mixed with the hair processing composition (A 2 ) at a weight ratio of 1:1, makes the pH of the hair processing composition (A 2 )in a range of from 8 to 12.  
   
   
       12 . The method for processing hair according to any of  claims 9  to  11 , wherein the organic acid added to the hair processing composition is an organic acid having a first dissociation index (pKa1) in a range of from 4.1 to 5.  
   
   
       13 . The method for processing hair according to any of  claims 9  to  11 , wherein the hair processing composition (A 1 )is composed of a first agent comprising the alkoxysilane represented by general formula (1) and a second agent comprising an organic acid and water, wherein the composition has a pH in a range of from 2 to 5.  
   
   
       14 . The method for processing hair according to any of  claims 9  to  11 , which comprises the step of heating the applied part after application of the hair processing composition (A 2 ) to the hair.  
   
   
       15 . The method for processing hair according to any of  claims 9  to  11 , which comprises the step of heating the applied part after application of the polymerization accelerator to the hair.  
   
   
       16 . A hair reforming composition comprising the following hair processing composition (A) and polymerization accelerator (B a ): 
 (A) a hair processing composition comprising an alkoxysilane represented by the following formula (1):      R 1   p Si(OR 2 ) 4−p    (1)    wherein R 1  and R 2  represent a straight or branched alkyl group having 1 to 6 carbon atoms or a straight or branched alkenyl group having 2 to 6 carbon atoms, p″R 1 ″(s) and (4−p)″R 2 ″(s) may be the same or different, and p represents an integer of from 0 to 3; an organic acid having a first dissociation index (pKa1) in a range of from 4.1 to 5; and water,    (B a ) a polymerization accelerator comprising an organic or inorganic acid having a first dissociation index (pKa1) less than 4.1 and which, when mixed with the hair processing composition (A) at a weight ratio of 1:1, makes the pH of the hair processing composition (A) in a range of from 1 to 4.    
   
   
       17 . A hair reforming composition comprising the following hair processing composition (A) and polymerization accelerator (B b ): 
 (A) a hair processing composition comprising an alkoxysilane represented by the following formula (1):      R 1   p Si(OR 2 ) 4−p    (1)    wherein R 1  and R 2  represent a straight or branched alkyl group having 1 to 6 carbon atoms or a straight or branched alkenyl group having 2 to 6 carbon atoms, p″R 1 ″(s) and (4−p)″R 2 ″(s) may be the same or different, and p represents an integer of from 0 to 3; an organic acid having a first dissociation index (pKa1) in a range of from 4.1 to 5; and water,    (B b ) a polymerization accelerator which, when mixed with the hair processing composition (A) at a weight ratio of 1:1, makes the pH of the hair processing composition (A)in a range of from 8 to 12.    
   
   
       18 . The hair reforming composition according to  claim 16  or  17 , wherein the hair processing composition (A) is composed of a first agent comprising the alkoxysilane represented by general formula (1) and a second agent comprising an organic acid having a first dissociation index (pKa1) in a range of from 4.1 to 5 and water, wherein the composition has a pH in a range of from 2 to 5.