Composition and device structure for iontophoresis

Abstract

Device structure 100 for iontophoresis provides electrode 101 and electrically conductive layer 102 . Electrically conductive layer 102 contains active ingredient D and basic water swelling methacrylate copolymer P 1 and/or acidic water swelling methacrylate copolymer P 2 . Electrode 101 and electrically conductive layer 102 are placed into a hollow of backing 103 and electrode terminal 104 is connected to electrode 101 through backing 103 . Adhesive layer 105 is set around backing 103 , and liner 106 to be removed when using the device, is placed so as to cover the hollow of backing 103.

What is claimed is:  
     
         1 . A composition for iontophoresis comprising at least one partially ionized active ingredient and a water swelling polymer which has a pH adjusting function.  
     
     
         2 . The composition for iontophoresis as claimed in  claim 1  wherein the water swelling polymer is at least either a weakly basic or weakly acidic water swelling polymer showing a characteristic of pH-dependent solubility.  
     
     
         3 . The composition for iontophoresis as claimed in  claim 1  wherein the water swelling polymer comprises at least either a polyamine of primary, secondary or tertiary amines or a carboxylic acid.  
     
     
         4 . The composition for iontophoresis as claimed in  claim 1  wherein the water swelling polymer comprises at least either a basic methacrylate copolymer or an acidic methacrylate copolymer.  
     
     
         5 . The composition for iontophoresis as claimed in  claim 4  wherein the basic methacrylate copolymer is soluble at lower pH than around weak acidic to neutral range and hardly soluble at higher pH than that.  
     
     
         6 . The composition for iontophoresis as claimed in  claim 4  wherein the acidic methacrylate copolymer is soluble at higher pH than around weakly acidic to weakly basic range and hardly soluble at lower pH than that.  
     
     
         7 . The composition for iontophoresis as claimed in  claim 4  wherein the basic methacrylate copolymer is aminoalkyl methacrylate copolymer E.  
     
     
         8 . The composition for iontophoresis as claimed in  claim 4  which comprises a basic methacrylate copolymer and further contains at least either hydrochloric acid or a weakly acidic material with at least one pKa within a range of 3 to 9.  
     
     
         9 . The composition for iontophoresis as claimed in  claim 8  wherein the weakly acidic material is at least one selected from organic acids and acidic amino acids.  
     
     
         10 . The composition for iontophoresis as claimed in  claim 4  wherein the acidic methacrlic acid copolymer is at least either methacrlic acid copolymer L or methacrlic acid copolymer S.  
     
     
         11 . The composition for iontophoresis as claimed in  claim 4  which comprises an acidic methacrylate copolymer and further contains a weakly basic material with at least one pKa within a range of 3 to 10.  
     
     
         12 . The composition for iontophoresis as claimed in  claim 11  wherein the weakly basic material is at least one selected from salts of organic acids and basic amino acids.  
     
     
         13 . An electrically conductive layer for iontophoresis which comprises the composition for iontophoresis as claimed in any of  claims 1  to  12 .  
     
     
         14 . A device structure for iontophoresis which is provided with the electrically conductive layer containing at least one of partially ionized active ingredients and a water swelling polymer having a pH adjusting function, and electrodes to supply electric current to said electrically conductive layer.  
     
     
         15 . The device structure for iontophoresis as claimed in  claim 14  wherein the active ingredient is a cationic material and the water swelling polymer is a basic methacrylate copolymer or a mixture of the basic methacrylate copolymer and the acidic methacrylate copolymer.  
     
     
         16 . The device structure for iontophoresis as claimed in  claim 14  wherein said active ingredient is an anionic material and said water swelling polymer is an acidic methacrylate copolymer or a mixture of the basic methacrylate copolymer and the acidic methacrylate copolymer.