One of the most environmentally friendly packaging containers sold today
is the egg box. It is made from paper pulp and was introduced in the 1930's.
Its design has not changed much since then.
It was replaced for a while with PET packaging but the public preferred
the natural look and feel of the paper pulp carton. It was even replaced
at one time with expanded polystyrene (the same materials as McDonalds
burgers are packaged in).
Pulp on the other hand does not require this quality surface but instead
is used with a textured, natural surface.
The egg box is a shell or Monocoque structure. It does not have a frame.
It relies upon the shape that it has been moulded into to give it its
strength. Monocoque structures are designed to be both light and strong.