BOPP is the abbreviation of "Biaxially Oriented Polypropylene". Clear BOPP film also refers to Biaxially drawn Polypropylene.
Production of clear BOPP film is made from polypropylene polymer melt through the long and narrow nose first sheet or thick film, and then within the special drawing machine, under certain temperature and the set speed, at the same time two or step by step in the vertical direction (vertical, horizontal) on the drawing, and through the appropriate cooling or heat treatment or special processing (such as corona, coating, etc.) made of thin film.
Brief introduction of clear BOPP film
Common clear BOPP film include: ordinary bidirectional stretch polypropylene film, heat seal bidirectional stretch polypropylene film, cigarette packaging film, bidirectional stretch polypropylene pearlite film, bidirectional stretch polypropylene metallized film, extinction film, etc.
Clear BOPP film is a very important flexible packaging material. Clear BOPP film is colorless, odorless, tasteless, non-toxic, and has high tensile strength, impact strength, rigidity, strong toughness and good transparency.
Clear BOPP film has low surface energy and corona treatment is required before gluing or printing.
After corona treatment, clear BOPP film has good printing adaptability, can be color printing and get a fine appearance effect, so it is often used as the surface layer material of composite film.
The production process
Clear BOPP film can be produced by tube film or flat film method. The properties of clear BOPP films obtained by different processing methods are also different.
Clear BOPP films produced by plain film method have higher strength and better thickness uniformity than those produced by tube film method due to large tensile ratio (up to 8-10).
Matters needing attention in production
In order to obtain a better comprehensive performance, the multi-layer composite method is usually used in the production process.
BOPP can be compounded with a variety of different materials to meet specific application needs.
For example, BOPP can be combined with LDPE(CPP), PE, PT, PO, PVA to obtain high gas resistance, moisture resistance, transparent, high temperature and low temperature resistance, cooking resistance and oil resistance. Different compound film can be used in the packaging of oily food, delicious food, dry food, impregnated food, all kinds of cooked food, monosodium glutamate, pancake, rice cake, etc.