ULWC, SC, MWC, MFC, LWC, HWC
Standard international acronyms for weights and grades of papers used in rotary offset and letterpress printing.
Coated stock can be identified HWC (heavy-weight coated), MWC (medium-weight coated), LWC (lightweight coated), or ULWC (ultra-lightweight coated).
All are wood pulp-based, but available in many varieties. MFC (machine-finished coated) paper is made primarily from ground wood pulp, has a grammage of 48 to 80 gsm, and may be high volume.
LWC paper is particularly lightweight stock for use on rotary offset machines. SC (supercalendered) paper is an uncoated wood pulp stock based mainly on ground wood and recycled content.
It features an additional finish applied by a separate supercalender.