Xerox 5790 参考指南

ABOUT PAPER

28

REGAL 5790 MATERIALS USAGE GUIDE

Paper weight is generally expressed as grams per square meter 
(gsm), a measure that makes it easy to compare any two pieces of 
paper, even if the papers are of different types. 

Paper weight is also expressed in terms of basis weight, which is the 
weight of 500 sheets of paper of a particular size. Because each 
type of paper (bond, offset, cover, index, etc.) is expressed in terms 
of a different basis size, a 20 lb bond paper and a 20 lb offset paper 
are not the same weight in gsm. 

The weight of some materials is described by the M value printed on 
the package (i.e. 21.64M). The M value is the weight in lbs of 1,000 
sheets of the size of the paper in the package. To convert the M 
value to gsm for 8.5 x 11” paper, multiply the M value by 7.527. To 
convert the M value to gsm for 11 x 17” paper, multiply the M value 
by 3.763.

Pt (point) value refers to the sheet thickness in mils (thousandths of 
an inch).  For example, 10 pt. = 0.010”, or 7 pt. = 0.007” thick paper.  
You cannot directly convert pt value to paper weight or stiffness.  
For most paper types, the maximum recommended paper weight of 
163 gsm will be equivalent to 7 pt or 8 pt paper.