Editing Offset printing (section)

===Materials===
The plates used in offset printing are thin, flexible, and usually larger than the paper size to be printed. Two main materials are used:
* Metal plates, usually aluminum, although sometimes they are made of multi-metal, paper, or plastic.<ref name="kipphan209">Kipphan 209</ref>
* Polyester plates, which are much cheaper and can be used in place of aluminum plates for smaller formats or medium quality jobs, as their dimensional stability is lower.<ref name="kipphan209" />