Japanese lacquer store Watanabe shoten | 漆芸材料専門店 渡邉商店(渡辺商店)Trivia about urushi

What is urushi

Please deal with Urushi as a living thing.
Where the urushi grow, environment,when or how to be gotten, how to refine, all of the condition affect the condition of urushi.The condition appears the urushi's scent,viscosity,dryness,gloss and transparency.

Urushi is a milk which comes out from the tree of urushi when it is scratched. Urushi is a milk for protecting its scratched point. Because of that, urushi is dried fast when a kind of molds increases in number, like high-temperature and humidity.

Generally speaking, urushi can be dried best in 20~25℃, Humidity being 70~80%. Surely this condition is good for urushi to be dry but this is not absolute.

We have a question from customers "The color of Urushi is not good." frequently. Though the reason for that is not simple,from hearings,customers raise their room's temperature and humidity as they can. Urushi become deep in color dried fast and have high transparency dried slowly.Because of that, the color of Urushi become good dried slowly. Urushi is a living thing which reacts slight changes in condition. That is why "Urushi is difficult.".

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Safekeeping method, expiration for urushi

Please remember that Urushi separates when it is left.When you use, you need to mix Urushi because the part of Urushi which dries up fast heaps on the bottom.

In general, instructions say "viscosity of Urushi increases in the case of having being left for 6 months (raw Urushi) or 12 months (refined Urushi). Using with new Urushi must be better."

In addition, you need to take raw Urushi(Seshime, Kizyoumi) for "raw food". In summer, it is better that you put them in a plastic bag and keep in refrigerator. If you don't, raw Urushi changes their property itself. After that, its color and smell are going bad, it cannot be dried up easily.

We have questions following.

Q, I have Urushi I bought years ago. Can I use them?
A,Urushi can hardly dry up because Viscosity increase.
If that is a tube, squeeze on a bowl,stir and paint glass plate for checking it dry up. (This test is called " taking the Tuke"). When it doesn't dry, we recommend you to mix new Urushi from July to September (good season for getting dry.).

Q,The tube is sealed. Can It last a long time?
A, In case of Urushi, it is the almost same whether it is opened or unopened. Urushi doesn't keep its quality for a long when it is unopened.

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Urushi allergic reaction

Whether you react to Urushi or not depends on your constitution.Your temporarily physical condition affects your reaciton However, if you are apt to react Urushi, continuing use of Urushi makes your reaction better.

When Urushi is stuck to your body, you need to wipe off by vegetable oil before Urushi drys up. If you are allergic reaction, you soak the point into warm salt water.(Sea bathing is a good way for reaction from old days.) For being healed, it takes some time, Urushi never leaves scars on your body.

(We don't shoulder the responsibility about urushi allergic reaction, so please accept it.)