The 'copper number' is a measure of the degree of cellulose degradation in paper. A lower copper number indicates less degradation and better permanence. For papers intended for permanent records, stringent standards are set. The Bureau of Indian Standards (BIS) recommends a maximum copper number of 2 for papers intended for archival and permanent use.
What is the recommended level of 'copper number' for the paper for permanent records? - (5) Question not attempted
Asked in Department Recruitment 2024 (Chemist) 2024 · Topic: Physical and Chemical Changes, Solution (Definition and Characteristics of Chemical Changes (Chemical Reactions))
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