Some questions about printed materials (7)

What is white cardboard?
White cardboard is a kind of thick and firm white cardboard. It uses 100% bleached sulphate wood pulp as raw material. After free beating, talc is added to a higher degree of sizing (with a sizing of 1.0-1.5mm). White fillers such as barium sulfate are made on a Fourdrinier paper machine and are made by calendering or embossing. It is mainly used for printing business cards, invitations, certificates, trademarks, and printed materials for packaging and decoration.

White cardboard is classified into three grades: A, B, and C. Its basis weight is 220 to 400 g/m 2 , and white cardboard and other flat papers are 787×1092 mm and 880×1230 mm. The whiteness requirement of white cardboard is not less than 92% for class A, 87% for class B, and not less than 82% for class C. Smoothness varies according to the quantitative and grade requirements, generally not less than 20 ~ 40s (embossed white cardboard without smoothness requirements). White cardboard also requires a high degree of stiffness and bursting resistance. The paper surface should be flat, no paper spots such as spots and streaks should be allowed, and warpage should not occur.