Satake Glass

A Working Glass-Rod Factory in Izumi

Satake Glass (佐竹ガラス, Satake Garasu) is a maker of colored craft-glass rods in Saiwai 2-chome, Izumi City, Osaka Prefecture, founded in 1927, and six buildings on its premises, the main house, office, melting plant, workshop, mixing factory and guardian shrine, were entered on the national register as Registered Tangible Cultural Properties on April 24, 2001. All six were registered on the same day, under consecutive registration numbers 27-0135 to 27-0140.

What makes the site unusual is how little separates home from factory. A two-storey Japanese-style house holds the southern corner of the plot. A small office is attached to it, and behind them the timber sheds of the works run back into the lot, one of them still sheltering a glass furnace. A tiny shrine keeps another corner of the compound. Living, working and worship share a single property, and the joins between them are still intact.

Izumi City's own heritage guide singles out exactly that point: the traditional main house and office have been kept together with the factory as one working ensemble. Satake Glass was the first property in the city to be placed on the national register.

Colored Rods and a Local Craft Economy

The product here is the raw material of lampworking, sometimes called flamework: slender sticks of colored glass that craftspeople melt in a torch flame and wind around a mandrel to make beads, or tease into tiny animals and pendants. Japanese beadmakers call the finished beads tonbodama, literally "dragonfly beads." Manufacturing and selling these color rods has been the company's core business since it started.

Izumi has long been a center for glass craft and imitation pearls. The Kansai Bureau of Economy, Trade and Industry's guide to industrial sites notes that Satake Glass supplied both the glass for local craftwork and the core beads for the city's imitation-pearl industry. The same guide, like the company itself, describes this as the only factory in Japan that has made colored glass rods for craft use continuously since before World War II.

According to the company history, the business was founded in January 1927. In 1994 a lampworking studio called Ryu Kobo (流工房) opened on the site, and classes for the public followed. The company also reports that Izumi glass (Izumi Garasu) was named a Traditional Craft Product by the Minister of Economy, Trade and Industry in October 2024. The registered buildings are not a museum set: they are the working floor of that craft.

How the Six Buildings Fit Together

Read side by side, the Agency for Cultural Affairs' descriptions map out the compound. The two-storey main house stands on the corner at the southern edge of the site, with the single-storey office attached to its northwest face. Northwest of the office is the melting plant, which houses the furnace. The L-shaped workshop adjoins the melting plant's east side and fills the back of the lot, while the mixing factory, where raw materials are blended, adjoins the melting plant's north side. The small guardian shrine, in the Nagare-zukuri style, occupies a corner of the property.

The main house dates to 1941; the other five buildings are recorded simply as early Showa period. All the factory buildings are single-storey timber structures under tiled roofs, Japanese in outline. Inside the melting plant and workshop, however, posts braced with diagonal struts on all four sides carry a King post truss roof, a Western framing system tucked beneath a Japanese exterior.

The six were not registered on identical grounds. The main house qualified as a building that "serves as a model of design," the standard reserved for architecture valued for its form. The office, melting plant, workshop, mixing factory and shrine were registered as buildings that "contribute to the historic landscape of the country," in other words, as parts of an ensemble whose value lies in the whole.

Tours, Workshops and Getting There

Satake Glass is an operating factory, and both tours and hands-on sessions require a reservation. The company lists its hours as 9 a.m. to noon and 1 p.m. to 5 p.m. on weekdays. No rod-making takes place on Mondays, and on Saturdays and Sundays only the classes run. Occasional closure days, including the New Year period, are posted on the company website.

The factory tour is free and takes about 20 minutes. The Kansai Bureau's guide gives Tuesdays and Wednesdays, with morning and afternoon slots. If the furnace pot cracks, or the day's mixing and melting schedule doesn't cooperate, rod-drawing may not be on view. Published booking deadlines vary between sources, so the safest course is to phone the company (+81-725-41-0146) as soon as your dates are fixed.

At Ryu Kobo, a tonbodama bead-making session costs 3,000 yen per person, materials included. Weekday sessions start at 9:30 a.m. and 2 p.m. and bundle a factory look-around, one hour at the torch and 40 minutes of annealing while the beads cool. There are also sessions on the first to fourth Saturdays (taught in Japanese only) and on the second to fourth Sundays. The Kansai Bureau's guide says tours can be given in English and workshops in English and Chinese, depending on which staff are in, so mention your language when booking. Ask about photography at the same time.

The nearest station is Shinodayama on the JR Hanwa Line, about a 10-minute walk to the north-northeast. By car, allow about 10 minutes from the Sukematsu exit of the Hanshin Expressway Bayshore Route, or about 5 minutes from the Toriishi exit of the Sakai-Senboku Road; the company notes parking for 7 cars. The address is 2-11-30 Saiwai, Izumi City.