Measuring pH is essential not only in finding the chemical characteristics of a substance but also as the first step toward managing chemical reactions. Currently, pH measurement is used in various fields, including nearly all industries that deal with water, not only the chemical industry, but public organizations, agriculture and fishery-related industries and biological industries, as well.
We would like to discuss fields where pH measurement is important and why.
In the textile industry, measuring pH is important in product testing, such as how a fabric reacts to things like perspiration, especially when developing synthetics, to ensure safety and durability.
Of course, pH measurement is indispensable in the process of dyeing, because permanence and processing speed depend on the pH of the dye bath, which is automatically adjusted to maintain proper pH.
Also, pH measurement is applied when creating artificial perspiration to be used in color-change testing.
Measurement of pH is carried out in the manufacturing processes of paper and pulp more often and continuously than any other industry. To reduce the consumption of chemicals and prevent corrosion of equipment, pH is controlled in the process of digestion, bleaching, creating of pulp to the manufacture of finished paper material products. Also, the durability and drying speed depends on the pH of the paper itself. Therefore, pH is strictly checked and adjusted as a vital part of quality control.
As pH measurement is essential for control of chemical reactions, it is carried out in the course of nearly all production of chemical products, be it plastics, fertilizers, electronic industrial materials such as semiconductors, cements, or glass. In order to optimize the desired reaction and to prevent unwanted reactions, controlling the pH of solutions is very important.
For example, in the manufacturing process for plastics, pH is strictly managed in the processes of producing long-chain molecular products, especially the processes of polymerization and condensation. Also, pH is controlled for efficient production of chemical fertilizers such as nitrogen fertilizers, potash fertilizers and phosphate fertilizers.
Also, pH measurement is very important both in the mixing process of silicate in the case of cement and in combining processes at high temperature in the case of glass manufacturing. The transparency of finished glass is also influenced by pH.
In oil refineries, pH is measured during the desulfurization process that removes sulfur from oil. Measurement of the pH of bioethanol (JIS name: fuel ethanol) is also standardized in JIS (JIS K2190, 2011).
Each metal tends to dissolve in solution of a certain pH by nature. Based on this characteristic, when extracting a particular material from crude ore or mixed metal, pH is controlled so as to extract only the desired metal without dissolving the slag. For example, if you place a mixture of copper and zinc in acid electrolytic solution and electrolyze it, only copper is separated out at the cathode.
In this field, pH measurement is applied to plating, etching of metal surfaces and the manufacture of batteries.
Control of the pH of a plating solution greatly affects the finish. Without proper control of the pH of a plating solution, the finished plating will be likely to peel and will not have the optimum color and luster. Anodic oxidation processing is used in coating cooking utensils to produce a coating like the film that forms on aluminum objects, and controlling the pH of the processing solution is critical to achieving the desired finish. In advanced factory painting processes, pH is a vital factor in achieving paint finishes of the quality required for manufactured goods.
Controlling the immersion liquid in offset printing, the most common printing method, involves very complex factors.
Adjustment of pH is one of the essential items, because it greatly affects the dryness of ink and color tone and color definition of photographic printing.