| 摘要 |
PURPOSE: To provide a writing board device, with which homogeneous writing lines can be obtained, the lines, characters or the like written on which are seen easily and which can be employed for various uses. CONSTITUTION: The writing board device (1, 20) is made of a non-absorbable material and has a surface arithmetic mean roughness Ra of 1 or more and below 5 and further has a writing board member (4, 38) for a predetermined solid drawing material.
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