中ちゅう性せい紙し

noun

neutral paper; acid-free paper; archival paper

Technical term for paper with a neutral pH, often used for preservation and archival purposes. Also called alkaline paper.

• この本ほんは中ちゅう性せい紙しに印いん刷さつされているので、長ちょう期き間かん保ほ存ぞんできます。

  This book is printed on acid-free paper, so it can be preserved for a long time.