You cannot use documentation and mailing.
Do not expose to temperatures greater than or equal to 60 degree C.Ink becomes colorless.
There is a clear handwriting to be around -10 degree C to return.
Depending on the paper like thermal paper, may notsuit
Superthin 0.5-mm ball
Water gel ball-point
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Originally the document is requested to be described with a ballpoint pen or the like so that it can not be tampered later, but if you mention the uneasy place to write erroneously in the kore, it can be corrected later so it is safe. Although it differs from the purpose of writing with a ballpoint pen etc. which can not erase the document (^ ^; Since the letter written is apparently different from the ballpoint pen etc. blurredly, so that the appearance of the written letter approaches the ballpoint pen more It would be perfect if you could improve it.