The most important fact when it comes to label material is the top finishing. Rough untreated paper is usually not suitable for printing. A good paper choice is calendered paper (Vellum) or even better a coated material (Chromolux). The smoother the surface, the better the suitability for printing with thermal transfer printing systems.
A specific case is applicable for printing with inkjet systems. The paper must have a certain absorbency for ink and this require special materials for inkjet printing. The manufacturing process of inkjet printable materials for plastics like PE or PP is very expensive, which is reflected in the material purchase price.
There are many different kinds of plastic labels. Depending on the application you have to look, which labels working best. For example PE labels (polyethylene) often used as decorative labels for labeling of product packages as they are soft and flexible with a good resistance against oils and greases.
Both, the PE and PP (polypropylene) labels regulary used as pallet labels as they are very well suited for short outdoor usage. One difference between both plastic labels is the fact that PP labels have better stiffness and a higher transperency, which makes them perfect choice for automatic application and also for transparent "No Label Look" applications.