Waterproof spray is “must-have” for me. Outdoor activity inevitably makes my garment soiled. I wash them every time I come home. But for next use, it is necessary to prepare for rain unexpected or not. Crossing streams along the trails requires garments with water repellant properly. A can for waterproof spray becomes light quickly for me. I am thankful for this 21st century product for making my life easier. How did our ancestors cope with the problem of wet garment and soiled clothing? They did not have waterproof spray for sure. But there was, and is, an organic substitute. Have you ever heard “Kakishibu 柿渋”, aka persimmon tannin?
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| The current spray I’m using
for waterproof treatment. The can is very light … |
Before fluororesin, silicone resin, and plastics, Japanese used organically processed persimmon tannin for waterproof, bug repellent, and preservative to almost everything. It was used for walling during construction. For UNESCO World Heritage Sites in Japan, usage of Kakishibu for materials is ubiquitous. For making tools for fishing, the final coating with Kakishibu was (and is, for luxury brand these days) the MUST. When applied to the surface of traditional Japanese paper, it can make the paper suitable even for raincoats and umbrellas. To make (high-end) Japanese lacquerware, persimmon tannin is essential as the base. Japanese samurais used it for make their garments durable enough in battlefield for more than a millennium. There is an old book, written in 918 called “Honzo-Wamyo 本草和名,” for herbal medicine in Japan, which discusses the utility of Kakishibu.
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| An ancient raincoat I found in
a museum for Lake Tanzawa Commemorative Center. In this mountainous area, villagers of yesteryears used this straw-raincoat made of straws and coated the surface with persimmon tannin to make waterproof stronger. |
In the 21st century, scientists are still researching the power of the product and thinking about the usage of it for our daily life. Persimmon tannin soap would be the most familiar product we can find these days in drug stores. Its cleaning power is strong enough to wash over that “particular smell” of teenage boys and middle/senior aged gents. Warning: heavy usage of it for ladies is not recommended. My senior citizen mom was a heavy user of Kakishibu soap. She was scolded by her doc when she was treated for eczema. The magic of the product is from its potential for sterilization. Traditionally, several communities used cloth treated with persimmon tannin to sieve water from wells and streams and to procure potable water. There is a published paper reporting deactivation of norovirus using persimmon tannin. Several researchers even search for methodologies to prevent spread of COVID-19 by Kakishibu. Persimmon tannin is a powerful staff. In more “peaceful” modern usage, persimmon tannin is very important to make Japanese SAKE clear. It can remain a fresh brew without distillation although it is basically fermented rice porridge. Persimmon tannin is VERY important for Japanese culture.
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| Kakishibu Soap. Really popular cosmetics, especially among males in Japan. |
Tannin itself is a material for tanning leather but cannot act as waterproof. On the other hand, persimmon tannin cannot permeate rawhide and so cannot tan skin but has the power of water repellent. Why do they differ? In the process of making persimmon tannin, sugar of persimmon is fermented and becomes stable. When the persimmon tannin meets moisture, the sugar absorbs H2O in the air and solidifies it, i.e. goods coated with Kakishibu are waterproofed. That’s why persimmon tannin was used widely in this very humid Japanese archipelago. How to make Kakishibu? It does not require rocket science but asks patience for ‘cooking’ it. Next week, I tell you how to cook it. I have not done it by myself, but the product is available from internet (for example from here). The reasons why I did not make it will be clear next week. (It’s not an excuse!.) Please stay tuned for next week. 😉
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| The store-bought Kakishibu
Niiharu Lovers use |
If you find a problem in the greenery of north-half of Yokohama, please make contact with
Office for the Park Greeneries in the North
北部公園緑地事務所
Yokohama Municipal Government Green Environment Bureau
横浜市みどり創造局
Phone: 045-353-1166
FAX：045-352-3086
email: mk-hokubukoen@city.yokohama.lg.jp
