The term "soda" and other related terms appeared for the first time in Japan in books translated in the mid-19th century. Glass (pidoro) and soap (shabon) came to Japan earlier with the Christian mission, but their manufacture did not develop into a large industry under the Shogun's regime.
The soda industry, as now we understand it began in 1881, when the government introduced the Western technology for mintage as a national project by the finance department at the Mint and the Printing Bureau. Although the traditional Leblanc process was being challenged by the new Solvay process, the former was the only choice available to Japan: the country had to start with an outdated technology.
The Leblanc process uses salt and sulfuric acid as raw materials. Salt production in Japan was then in surplus, and thought to be sufficient for the raw material for soda production. Sulfuric acid had been manufactured since 1872 by the Mint. Starting up the soda industry was thus thought to be realistic enough.
In 1881, the Mint began production of soda ash and artificial fertilizer as outlets for its sulfuric acid. In the same year, the Printing Bureau also started the manufacturing of soda ash and bleaching powder for making banknote paper. In 1885, the Printing Bureau established a new factory in Oji to manufacture soda ash, sulfuric acid and bleaching powder in full swing. The production project by the Mint, however, was later privatized.
The factory in Oji was shifted from the Printing Bureau to the Ministry of the Imperial Household and renamed the Oji Manufacturing Site in 1890. The business was continued under the supervision of the authority until 1895, when the sulfuric business was divested to the Army and the soda production was privatized. Since then, the Japanese soda industry has consisted of solely private enterprises.
The product quality was, however, not competitive because of the outdated Leblanc process, while the advantage of the Solvay process had become clear by the mid-1890s. Also the Leblanc process could hardly be improved. In the early 1910s, only two manufacturers were active in Japan, and met only a small part of the domestic demand for caustic soda and soda ash.
The chloralkali process in Japan took off after 1912; the Solvay (ammonia-soda) process also became active in 1916. The latter grew since that time, under governmental subsidization and with the introduction of new technologies. Eventually, it came to cover the entire domestic demand in 1935.
By the end of WWII, the Japanese soda industry had fallen far behind the international level, due to war damage and technological stagnation. Filling this gap was the first step to reviving the industry.
A modified ammonia-soda process, adopted Japan's own technology, that also produces ammonium chloride, a chemical fertilizer, was a welcome contribution to the food supply badly needed after the war. Subsequently, however, ammonium chloride demand diminished due to the introduction of mixed fertilizers and the start of fertilizer production in China; only one manufacturer has survived. Similarly, the eleven soda ash producers in 1938 were merged into four after the war, and two then dropped out due to severe competition with imported natural soda ash, exacerbated by trade liberalization.
The growth of electrolytic soda production after the war was particularly accelerated by the surging chlorine demand for vinyl chloride from the mid-1950s on, and the demand for chlorine surpassed that for caustic soda in 1965. This led to an ample supply of low-cost, high-quality electrolytic caustic soda, which drove Solvay caustic soda out of the Japanese production scene in 1966.
Mercury cells rivaled diaphragm cells up to 1949, but later became the mainstream process at the highest technological level in the world until 1973, when the disastrous mercury poisoning affair forced the government to ban the process. As a result, all mercury cells in Japan were replaced by diaphragm or membrane cells by 1986. The lower product quality and higher production costs of diaphragm cells prompted the development of membrane cell technology. It was the hardest experience for the soda industry to invest in developmental work, after spending more than 300 billion yen for process conversion.
The membrane cell technology, by the support and effort from the government and related parties, successfully became one of Japan's representative technologies. It was first commercialized in 1979, and had replaced all of the other types of chloralkali cells in Japan by 1999. Characterized by high product quality, energy economy, and many other advantages, membrane cell technology has been exported to many countries throughout the world.
The soda industry of Japan is now developing the next-generation technology of gas diffusion electrodes, which should further reduce energy consumption. Our challenge for the new era never ends.