Why do old newspapers eventually turn yellow?

Changes in the colour of the newspaper is caused by a type of chemical reaction known as oxidation. As newspapers are made out of wood, they contain a substance called lignin. Lignin contains molecules that are responsible for the colour of the paper. When newspapers are exposed to sunlight and air, oxidation occurs, causing the newspapers to absorb more light, which gradually darkens the paper from white to yellow.

Share the knowledge
  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •  
  •