The color of the bags above are known as kinari in Japanese. Strictly speaking, however, the word doesn't really refer to the color itself but to the unbleached or undyed raw fabric and thread. With the passage of time, the term has come to denote the color of the raw materials.
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Enjoying the colors: H-04 Series
From children to grown-ups, everyone's "School Commuting Bag"
Kigi: Seasonal colors of trees
Canvas randoseru, a ransel type backpack (Japanese-style school backpack)
In Japan, most elementary school children use the box-shaped backpack called randoseru. Starting school can be an anxious time that is intertwined with fun and excitement as well as new experiences. The randoseru accompanies the child each day to school, sharing and commiserating with each new experience or set back.