Simple black and white films are made of three layers. First, there is a light-sensitive emulsion layer. The emulsion contains grains of silver salt that are able to absorb light and react with a developing chemical to break down into pure silver, remove the silver, and reveal an image on the negative. Second is a layer of plastic to support the emulsion. Third is an anti-halation layer that is used to capture light and refrain it from bouncing back to the emulsion. This final layer eliminates blurry images or foggy film.