Types and characteristics of label base materials for plastic turnover boxes

Compared with the paper label base material, the plastic label base material has higher gloss, smoother surface, excellent water (wet) resistance and excellent dimensional stability in wet environment. In recent years, the application of plastic label base materials has become more and more extensive.

Polyethylene film (PE)

PE turnover box film has certain similarities with PVC film in physical and mechanical properties, and is widely used in packaging field due to its excellent dimensional stability. Through common industrial corona treatment, the surface of PE film can be printed and coated. The corona effect can last for at least 6 months (the corona level is greater than 38mnm) as required. PE film can be subjected to corona treatment (Corona refresh) again before printing.

PE turnover box film can be used in different application fields by adjusting its thickness. For example, 150 micron films are used in chemical and industrial products; 80 to 100 micron film is used for shampoo bottles, cosmetic bottles and daily necessities. PE film is a kind of polyolefin carbon water polymer. Its chemical composition determines the environmental compatibility and high recyclability of PE film.

Polypropylene film (PP)

Unidirectionally and biaxially stretched polypropylene casting turnover box film can combine its excellent mechanical processing performance, good surface visual effect and relatively thin film thickness. Compared with PE film, the disadvantage is that the corona treatment effect of PP film is relatively short (at the corona level of 38mnm, the printing applicability is usually 1 to 1.5 months after corona treatment).

Similar to PE film, PP film can also be applied to different application fields by adjusting its thickness. For example, 60 micron PP film can be used for hard and highly transparent bottles: shampoo, cosmetics, food, cleaning liquid, etc; 50 μ M can be used on packaging carriers with "no label" feeling such as beverages, nutrition products and drugs; 30-40 micron PP film can be used on booklet labels and packaging carriers with "no label" feeling such as beverages, cosmetics and sanitary products.

PP film is also a carbon water polymer of polyolefins. Its chemical composition determines the environmental compatibility and high recyclability of PP film.

Polystyrene film (PS)

The chemical structure of PS determines that it has excellent punching performance and excellent dimensional stability of turnover box at normal temperature. But its resistance to (barrier) oil (fat) is poor. PS is not a polyolefin. Its environmental compatibility and recyclability are relatively inferior to polyolefin polymers.

Polyester film (PET)

Polyester film is a super transparent film with excellent dimensional stability. Its excellent visual performance and relatively thin thickness make it an excellent choice in the field of "label free" label application.

12 micron PET film can be used as surface composite material. The appearance of high texture and its protective function are reflected in this material at the same time. 50 micron pet label film can be used on packages sensitive to water, grease and chemicals.

Although pet is not a polyolefin, it can be effectively recycled and granulated after cleaning and shredding and made into fiber, film and PET bottle.

Polyvinyl chloride film (PVC)

The main characteristics of PVC turnover box film are the diversity in color, thickness and hardness. At present, PVC raw materials do not contain heavy metals, but softeners are still used. The chemical structure of PVC determines that this material is suitable for outdoor use (2 to 7 years of outdoor use validity). The environmental compatibility and recyclability of PVC film have been controversial for a long time because of its chloride content.

In plastic turnover box labels, polyethylene (PE) and polypropylene (PP) films have become the most widely used plastic label substrates due to their relatively wide processing temperature range (to 260 ° C) and excellent mechanical and rheological properties.