URUSHI FAQ

Is Urushi lacquer safe to use?

Urushi is the refined sap of the Urushi tree. It has strong adhesive properties and is used as a lacquering material that becomes extremely durable once hardened and produces a glossy finish. Urushi is a 100% natural material and does not contain toxic chemical additives.

 

Why is Urushi allergic?

Raw Urushi contains urushiol which can cause an allergic reaction upon contact with the skin, similar to that of poison ivy. Therefore, please take the necessary precautions when applying Urushi lacquers, such as wearing rubber gloves and long-sleeve shirt.

The best thing about Urushi lacquer is that after the application is finished and the lacquer is completely dried, no such allergic reaction will occur. It is then totally safe to eat from or with the items lacquered with Urushi because it is no longer toxic and it has antibacterial effects so it is suitable for food storage as well.

 

Is Urushiware safe to use?

Once Urushi has dried, it is almost completely nontoxic. Furthermore, Urushi has antibacterial effects which makes suitable for food storage.

 

How can Urushiware be environmentally-friendly?

With its raw materials of wood and Urushi, Urushiware is a combination of two of nature’s blessings. Furthermore, there are no harmful side effects associated with the production process and it creates minimal environmental pollution and ecological damage.

 

Can you tell me more about the process, how to use the Urushi lacquer ?

We receive this question daily, but this is like asking how to teach someone to play a violin over email! There is no way to learn how to lacquer an Urushi just from reading about it! Unlike chemical-infused paint you get from the store, Urushi is a living creature which breathes! It has numerous features that other chemical paints don’t have. It works differently depending on humidity, temperature and drying time. It is complicated and impossible to explain unless you try it out for yourself and learn from experience.

 

How do you dry Urushi lacquer?

Urushi is normally hardened with 75-90% humidity and temperature of 15 degrees Celsius (about 59 degrees Farenheit) or more. In old times Urushi finishing could not be done during the winter due to low temperatures and dryness.

Most people use a “Muro” (also known as Furo), a direct translation "box", as a drying container. By placing wet towels and closing the container completely, the humidity and temperature are kept at a high level.

 

How long does it take to dry Urushi lacquer?

It varies with size and layer thickness, in addition to the humidity and temperature. On average, one layer takes 1 to 2 weeks.

 

Is Urushi heatproof?

It is heatproof up to 120 degrees Celsius or 248 degrees F (some say up to 150 degrees Celsius or 302 degrees F).

 

Is Urushi waterproof?

It is also waterprooof as you can see from Urushiwares.

 

How many layers of Urushi is required?

This cannot be predicted preemptively as it all depends on materials and purposes! Many Urushiware has dozens of layers; we've even seen Urushi-lacquered fountain pens with 50 different layers!

 

How do you make colored Urushi?

Colored Urushi is usually made from a Kijiro Urushi and a pigment. The standard blending ratio is 1:1, however subtle adjustment is always required depending on the color and pigment type.

To make a glossy colored Urushi, Shuai Urushi is used.

Making the correctly colored Urushi is quite difficult to learn by reading about it, but expertise comes with more practice.

Pre-made colored Urushi is available in 8 different colors on our website.

 

The Best Way to Use Urushi Lacquer and Handle Urushiware...?

Proper handling and caring for all kinds of urushiware is not complicated but there are some points to keep in mind which are described below:

 

Washing

Urushiware can be washed with a conventional neutral household detergent. Scrubbing brushes and steel wool that contain abrasive material in them will cause scratching and so should be avoided.

Storing

Please refrain from automatic dish washers and dish dryers as boiling water and hot air can damage Urushi.

No Microwave Ovens

Electromagnetic waves burn Urushi so under no circumstances should Urushiware be put into microwave ovens.

No sunlight

Urushi deteriorates by being exposed to ultra-violet rays and so should not be placed in areas that get direct sunlight for long periods of time.

Is it possible to eat from the repaired bowls if I use your Kintsugi Repair Kit, or is it not food-safe?

As previously mentioned, Urushi lacquers are 100% natural and no chemicals are added.

However, if you need it to be 100% food-safe, you should choose the genuine gold or genuine silver powder for your repairs instead of economical colored powders, such as alternative or pearl-made powders. Since artificial items are not made for food-safety purposes, be sure to choose genuine powders which are considered food-safe.

 

Can I repair my broken wine glass with your Kintsugi repair kit?

Unfortunately, no.

You might have seen kintsugi repaired glasses before, but our kit works best with broken potteries and porcelains.

Repairing glasses will require a different Urushi lacquer with different repair processes than normal kintsugi repair.

 

Urushi’s drying time takes too long. How fast can I complete the Kintsugi repair?

Well, Kintsugi repair is a form of Japanese art, not just a DIY repair method.

It has a long history which was practiced by our ancestors from Edo era (year 1603 to 1868).

If you want to repair your broken ceramics quickly, forget about Kintsugi and use epoxy or super-glue instead.

The most important philosophy behind Kintsugi repair is to treat the repair as part of the object’s history as opposed to treating the repair like it should be hidden, as if it never happened.

Kintsugi repair is a time-consuming process and some say it should take a year to finish.

If you can respect and understand this concept, you should be able to enjoy the repair process.

 

Can I fix any breakage with your Kintsugi repair kit?

No.

If your broken pottery has a missing area of 5mm (=0.196 inch) or more, you should either keep adding numerous fillers for long periods, or use another material, such as piece of wood, to fill the crack. This process is not explained in our kit manual.

 

I am not happy with the result of my Kintsugi repair. What’s wrong…?

If you are a beginner, it is natural. Nobody does it perfectly the first time.

Once again, Kintsugi is an art form.

You practice more, and you’ll get better with time. Many of our students and users are doing a great job with practice.

Do not rush. Take your time. If you are doing this simply for a practical reason, Kintsugi repair might not be for you.

 

Kintsugi Repair FAQ

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