What is this that the printing factory saw?

This kind of thin and pointed material with texture on the surface seen in the printing factory may be one of the following:

leather belt

In printing, metal plates are often used to make printing plates. It has the characteristics of smoothness, high hardness, few spots and good barrier. The surface of the metal plate can be specially treated to form braided lines to increase its printing effect or durability.

Special plastic photosensitive material

This material is also common in printing plants, especially for special printing or plate making. They have special light transmission, flexibility and weather resistance, and may have surface texture to enhance their physical properties or visual effects.

Blade or cutter

During the printing process, a blade or cutter can be used to cut, trim or clean printed materials. These blades or cutters are usually very sharp, and their surfaces may be specially treated to form a textured or serrated shape to enhance their cutting effect or durability.