Umbrella Reappear and Disappear Design

Walking around town window shopping I came across this line of umbrellas and one of them had water pouring on it. Moving closer to the object it seems that it was not any ordinary umbrella. When it gets wet the design appears. Once it dries out it goes back to being without a pattern. I was thinking that we do not have that back home, but then again it does not rain enough to appreciate it. If I lived in an area that rains frequently then I would have bought it. Maybe next time when I visit Japan there will be a smaller version of it that I could bring home and leave in my car until that one rainy day.