Two types are available, black leads in which the binding agent is an organic polymer (designated by the letter "P"), and black leads in which the binding agent is clay (designated by the letter "C"). Classification is made according to the degree of hardness. Part 1 deals with the classification, dimensions, performance requirements and testing.
WITHDRAWN
ISO 9177-2:1989
95.99
Withdrawal of Standard
Jun 1, 2022
PUBLISHED
ISO 9177-2:2022