(also referred to as 'silkscreen' or 'screenprint') is a colour stencil printing process in which a special paint is forced through a fine screen onto the paper beneath. Areas which do not print are blocked with photo sensitive emulsion that has been exposed with high intensity arc lights. A squeegee is pulled from back to front, producing a direct transfer of the image from screen to paper. A separate stencil is required for each colour and one hundred colours or more may be necessary to achieve the desired effect. A serigraph differs from other graphics in that its colour is made up of paint films rather than printing ink stains. This technique is extremely versatile, and can create effects similar to oil color, transparent washes as well as gouache and pastel.