set terminal emf {<color>} {solid | dashed} {"<font>"} {<fontsize>}
color is either color or monochrome; solid draws all curves with solid lines, overriding any dashed patterns; font is the name of a font; and fontsize is the size of the font in points.
The first two options can be in any order. Selecting default sets all options to their default values.
Examples:
set terminal emf 'Times Roman Italic' 12 set terminal emf color solid # no pesky dashes!