Definition (English)
C1S (Coated One Side): Paper or paperboard with coating on one side only—a smooth coated print side and an uncoated back.
C2S (Coated Two Sides): Paper or paperboard coated on both sides, providing uniform smoothness, brightness, and printability front and back.
Typical Uses
C1S: Postcards, labels (adhesive backing), calendar covers/backs, folding cartons where the inside favors writeability, glue, or grip.
C2S: Premium covers/cards, retail cartons, and any job requiring high-quality two-sided print.
Traits & Selection
C1S: Polished look on the print face; back side is better for writing, lamination, or gluing and can reduce cost.
C2S: Consistent halftone reproduction on both sides—best for double-sided graphics and dense imagery.
Typical Basis Weights
Papers: 80–200 gsm; Boards: 200–400 gsm+.
Often specified with board types like SBS/FBB C1S or C2S.