\DeclarePreloadSizes {<encoding>} {<family>} {<series>}
{<shape>}
{<size-list>}
Specifies the fonts that should be preloaded by the format. These
commands should be put in a preload.cfg file, which is read in when
the LaTeX format is being built.
Read preload.dtx for more information on how to built such a
configuration file.
Example:
\DeclarePreloadSizes{OT1}{cmr}{m}{sl}{10,10.95,12}