| abstract |
A multi-layered, chemical analysis material for analysis of an aqueous liquid, which comprises in one embodiment (a) a light-transmitting, water-impermeable support having provided thereon in sequence (b) a reagent layer and (c) a porous, sample-spreading layer, with (i) the reagent layer (b) containing a lake dye precursor dispersed in a hydrophilic binder, (ii) urease incorporated in the reagent layer (b) or in a layer adjacent the reagent layer (b), and (iii) a lake forming metal salt or lake forming metal oxide, which does not substantially inhibit the activity of urease, incorporated in the reagent layer (b) or in a layer adjacent the reagent layer (b) or a lake forming metal salt or oxide incorporated in a layer adjacent the reagent layer (b); and in a second embodiment the chemical analysis material includes (d) a radiation-blocking layer interposed between said reagent layer (b) and said porous, sample-spreading layer (c). |