Most frequently, the choice of paper stock for a print project is based on the weight of the paper, which is often given an additional designation for its intended use. For example, 20-lb Text, 80-lb Cover, 120-lb Card Stock, etc. (Note: the pound symbol “#” is often used interchangeably with the abbreviation “lb” to designate weight.) While the weight measurement of a paper stock gives a general idea of the thickness of a sheet of paper, it is not precise and can be somewhat confusing or misleading. For instance, 20-lb Text is not the same thickness as 20-lb Cover stock. And to make things even more confusing, for some paper stocks — particularly coated papers and card stocks — thickness is measured in “points.”
What are Points?
Using a micrometer caliper (a tool used to measure thicknesses), a precise thickness of a paper stock can be made. Typically in the U.S., where the imperial measurement system is still in use, this measure is expressed in fractions of an inch. Hence, one point equals 1/1000th of an inch (.001”). Therefore, 10pt stock would be 10/1000ths of inch thick (.010”), 12pt stock (.012”), 14pt stock (.014”) — the higher the point number, the heavier the paper stock. For general comparison purpose, an average sheet of 20-lb bond paper typically measures .004” in thickness.
Laminate Thickness: Mils
The thickness of plastic films (like trash bags) or plastic film laminates used in the printing industry are usually expressed or given in “Mils.” Mil, a term derived from the French word mille (meaning 1000), is equivalent to a point: 1/1000th of an inch (.001”). For example, a 1.5Mil laminate film is 1.5/1000ths of an inch (.0015”) thick; a 5Mil film is 5/1000ths of an inch (.005”) thick, etc.
If you have any questions about Points or Mils, give us a call at 330-597-8560. We’re happy to help you get the most out of your printing project.
Photo by Pierre Bamin
