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English definition of “acid-free”

acid-free

adjective uk   /ˌæs.ɪdˈfriː/ us  
Acid-free paper does not contain any harmful acid that can damage documents, paintings, etc.: The books are printed on acid-free paper so they will last for generations.
(Definition of acid-free from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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