Excerpt:
Reference is made to Patent Office action of April 13, 1964, in the above-identified application. It is well established that an aqueous solution of the disodium salt of ethylene diamine teraacetic acid has an acidic pH. in the attached literature from Geigy industrial Chemistry the pH of a 10% aqueous solution of sequestrene NA2 (the disodium salt) is given as pH 6.0.
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