33 | History of Glass: Japanese Glass Manufacturers, Handmade Glass Factories Part 3

Hello🎵 Previously, I talked about Ishizuka Glass / Aderia.

From now on, I will be talking about Sasaki Glass (at the time), and the current Toyo-Sasaki Glass.

Sasaki Glass is a long-established manufacturer of glass tableware and was the industry leader in glass cups for dining. It started not as a factory but as a wholesale dealer in 1902 (Meiji 35) when Sojiro Sasaki founded Sojiro Sasaki Shoten, a lamp wholesaler, in Kanda, Tokyo. Later, he expanded his business by actively purchasing products from close glass factories and selling them nationwide.

The second-generation, Shuichi Sasaki, joined the family business, Sasaki Glass Store, in March 1937 (Showa 12) after graduating from Keio University's Faculty of Economics. Later, before the war (the exact period is unknown), it is said that he established the company's first factory in Ujiie, Tochigi Prefecture. In 1940 (Showa 15), after obtaining a patent, they began production using Japan's first screen printing process. After the war, in January 1947 (Showa 22), the company was reorganized into Sasaki Glass Co., Ltd., and began wholesale sales of glass tableware in Nihonbashi Bakurocho, Chuo Ward, Tokyo. In September 1950 (Showa 25), they built the Tokyo Factory in Sumida Ward, Tokyo, and officially started their own production of hand-blown glass tableware and printing processes.

A major turning point for the Japanese glass industry was the installation of the H-28 machine, the first automated tumbler manufacturing machine in the East, at the Tokyo factory in February 1957 (Showa 32). This allowed for 24-hour automated production of glasses, leading to uniform and, in a sense, stable quality glass manufacturing. This ripple effect led to the closure and bankruptcy of numerous handmade glass factories throughout the country.

Another significant impact on the industry was in 1967 (Showa 42) when they began producing "HS" Hard Strong, glassware with a reinforced rim for tableware. This was a new product that shattered the notion that glass was fragile and difficult to handle. Afterwards, other companies began similar production, and the market became hyper-competitive.

It's a bit further down the line, but I'll talk about glass manufacturing/processing methods later. Globally, tempered glass refers to fully tempered glass where the entire glass is strengthened. Only in Japan are special glasses with only the rim strengthened sold. Simply put, fully tempered glass is less prone to breaking and easier to handle. However, if there's a slight scratch or external force applied to the glass, it shatters into fine fragments like a car window, scattering explosively. At that time, injuries occurred, which seems to have led to Japan's unique standards. I have a simple question: In overseas markets, standard fully tempered glass and rim-tempered glass unique to Japan exist. Was this perhaps used as a non-tariff barrier, under the guise of consumer protection, to prevent foreign glass from entering Japan?

Hard Strong has sold a tremendous number of units both domestically and internationally, and it is a product that resonates with restaurant owners when they hear "Sasaki Glass Hard Strong."