METHOD OF MAKING TEST DEVICE FOR DETERMINING pH IN HUMID AIR Russian patent published in 2012 - IPC G01N31/22 

FIELD: chemistry.

SUBSTANCE: method involves preparation of a matrix (substrate) and depositing thereon a mixture of indicator solutions, wherein the substrate used is nanostructured aluminium oxide which is prepared via anodic treatment of aluminium foil with thickness of not less than 60 mcm in sulphosalicylic acid with concentration of not more than 0.6 mol/dm³, anode current density of up to 1 A/dm² and anodic treatment time of 35-45 minutes and then holding for 20-24 hours in an equimolar mixture of aqueous solutions of sodium 4-(4-dimethylaminophenylazo)benzene sulphonate and 3',3'-dibromothymol-sulphophthalein with titre of 1 g/ml; excess solutions are removed from the surface of the substrate with distilled water and the finished test device is dried in a drying cabinet at temperature 50°C for 30-50 minutes.

EFFECT: high wear-resistance and reliability of the device.

1 ex, 3 tbl, 2 dwg