Patent ID: 7718123

Claim:
A detector tape for detecting mineral acids in an air stream comprising: a substrate impregnated with a formula solution consisting essentially of (a) a pH buffer material at a concentration of between about 8-9% by volume of the total volume of solvent, (b) a first coupling agent consisting of reagent grade chromotropic acid of between 0.07-0.10% by weight of the total weight of the solvent, (c) sodium nitrite reacting with the acid gas and a diazotization coupling agent to form the diazonium salt, said sodium nitrite having a concentration of between 0.25-0.38% by weight of the total weight of the solvent, (d) a sodium bromide stabilizer of between about 0.30-0.050% by weight of the total weight of the solvent, (e) said diazotization coupling agent of between about 0.15-0.35% by weight of the total weight of solvent, (f) a pH indicator of between 4-4.5% by volume of the total volume of solvent and (g) a humectant comprised of a polyalcohol of between 4-5.5% by weight of the total volume of solvent, with each element of the formula solution being dissolved in between 3.3 to 3.5 liters of methanol solvent.