PROBLEM TO BE SOLVED: To provide a vehicle-shaped picture book, consisting only of a paper product and highly safe with no worry that a child in infancy swallows a component of plastics and metals (axle etc.) by mistake, and having wheels that have excellent rotation capacity.;SOLUTION: The picture book is provided with the paper wheels, and paper axles that support the wheels, wherein the wheels rotate without slipping when being rolled on a wooden floor when at least one of contact surfaces of the wheels and the axles is coated with a rotation promoter.;COPYRIGHT: (C)2013,JPO&INPIT
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