"Sashiko" is form of decorative reinforcement stitching from Japan. The stitches were done to reinforce or repair weak spots or small tears in the fabric so that the fabric will hold up to more wear and also provide extra warmth.
The needle industry in Hiroshima dates back 300 years, and close to 75% of what is produced is exported outside of Japan. With those fine needles, you can sew through a fabric without catching a thread. They also have larger eyes for an easy threading and do not warp easily.
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