BCM Inks U.S.A. PCR Black is a unique water-based flexographic black ink for the direct print corrugated market. PCR Black utilizes inks and toners recovered during the inkjet and toner cartridge recycling process. BCM Inks developed this innovative product in association with Close the Loop Inc. Part of the outstanding success of this ink is due to the fact that for every 450-pound drum of PCR Black that is produced, some 200,000 inkjet cartridges are saved from landfills.