Multi layer plastic product, method of manufacturing same, and co-extruder.

摘要

The wall of a plastic product is made a laminated structure formed by colored resin layers and transparent resin layers. A transparent window (3) is formed at part of the circumference of the wall (10). The window is formed by removing the colored resin layer (6,8) at the window and filling the removed area with the transparent resin layer (5,11). Not all layers are discontinuous at the window area and other area of the wall, but at least one transparent layer is continuous over the whole circumference of the wall, thereby preventing the strength of the wall from being lowered at the window.