OPP film is a type of polypropylene film, which is called co-extruded oriented polypropylene (OPP) film because the production process is multi-layer extrusion. If there is a bi-directional stretching process in the processing, it is called bi-directional oriented polypropylene film (BOPP). The other is called cast polypropylene film (CPP) as opposed to the co-extrusion process. The three films differ in their properties and uses.
I. Main uses of OPP film
OPP: oriented polypropylene (film), oriented polypropylene, is one kind of polypropylene.
Main products made of OPP:
1, OPP tape: polypropylene film as a substrate, with high tensile strength, lightweight, non-toxic, tasteless, environmentally friendly, wide range of use and other advantages
2, OPP labels: for the market is relatively saturated and homogenized daily products, appearance is everything, the first impression determines the consumer's purchase behavior. Shampoo, shower gel, detergents and other products are used in warm and humid bathrooms and kitchens, the requirements of the label to withstand moisture and does not fall off, and its resistance to extrusion must be matched with the bottle, while the transparent bottles for the transparency of the adhesive and labeling materials put forward harsh requirements.
OPP labels relative to paper labels, with transparency, high strength, moisture, not easy to fall off and other advantages, although the cost is increased, but can get a very good label display and use effect. But can get a very good label display and use effect. With the development of domestic printing technology, coating technology, the production of self-adhesive film labels and printing film labels are no longer a problem, it can be predicted that the domestic use of OPP labels will continue to increase.
As the label itself is PP, can be well combined with PP/PE container surface, practice has proved that OPP film is currently the best material for in-mold labeling, food and daily chemical industry in Europe has been a large number of applications, and gradually spread to the domestic, there are more and more users began to pay attention to or use in-mold labeling process.
Second, the main purpose of BOPP film
BOPP: Biaxially oriented polypropylene film, also one kind of polypropylene.
Commonly used BOPP films include:
● general bi-oriented polypropylene film,
● heat-sealed bi-oriented polypropylene film,
● cigarette packaging film,
● bi-oriented polypropylene pearlescent film,
● bi-oriented polypropylene metallized film,
● matte film and so on.
The main uses of various films are as follows:
1、Ordinary BOPP film
Mainly used for printing, bag making, as adhesive tape and composite with other substrates.
2、BOPP heat sealing film
Mainly used for printing, bag making and so on.
3、BOPP cigarette packaging film
Use: Used for high-speed cigarette packaging.
4、BOPP pearlized film
Used for food and household producst packaging after printing.
5、BOPP Metallized Film
Used as vacuum metallization, radiation, anti-counterfeiting substrate, food packaging.
6、BOPP matte film
Used for soap, food, cigarettes, cosmetics, pharmaceutical products and other packaging boxes.
7、BOPP anti-fog film
Used for packaging of vegetables, fruits, sushi, flowers and so on.
BOPP film is a very important flexible packaging materials, widely used.
BOPP film colorless, odorless, tasteless, non-toxic, and has a high tensile strength, impact strength, rigidity, toughness and good transparency.
BOPP film surface energy is low, glue or printing before corona treatment. However, BOPP film after corona treatment, has a good printing adaptability, can be color printing and get a beautiful appearance, and therefore commonly used as a composite film surface material.
BOPP film also has shortcomings, such as easy to accumulate static electricity, there is no heat sealing and so on. In the high-speed production line, BOPP film is prone to static electricity, need to install static electricity remover.
In order to obtain heat-sealable BOPP film, BOPP film surface corona treatment can be coated with heat-sealable resin adhesive, such as PVDC latex, EVA latex, etc., Can also be coated with solvent adhesive, but also extrusion coating or co-extrusion laminating method can be used to produce heat-sealable BOPP film. The film is widely used in bread, clothes, shoes and socks packaging, as well as cigarettes, books cover packaging.
BOPP film initiation of tear strength after stretching has increased, but the secondary tear strength is very low, so the BOPP film can not be left on both sides of the end face of the notch, otherwise the BOPP film is easy to tear in the printing, laminating.
BOPP coated with self-adhesive tape can be produced to seal the box tape, is the BOPP dosage BOPP coated self-adhesive can produce sealing tape, is the BOPP usage of the larger market.
BOPP films can be produced by tube film method or flat film method. The properties of BOPP films obtained by different processing methods are different. BOPP film produced by the flat film method due to the large tensile ratio (up to 8-10), so the strength is higher than the tube film method, the film thickness uniformity is also better.
In order to get a better overall performance, in the use of the process is usually used in the production of multi-layer composite method.BOPP can be compounded with a variety of different materials to meet the needs of special applications. Such as BOPP can be compounded with LDPE (CPP), PE, PT, PO, PVA, etc. to get a high degree of gas barrier, moisture barrier, transparency, high and low temperature resistance, cooking resistance and oil resistance, different composite films can be applied to oily food.
Third, the main purpose of CPP film
CPP: good transparency, high gloss, good stiffness, good moisture barrier, excellent heat resistance, easy to heat sealing and so on.
CPP film after printing, bag making, suitable for: clothing, knitwear and flowers bags; documents and albums film; food packaging; and for barrier packaging and decorative metallized film.
Potential uses also include: food overwrap, confectionery overwrap (twisted film), pharmaceutical packaging (infusion bags), replacing PVC in photo albums, folders and documents, synthetic paper, self-adhesive tapes, business card holders, ring binders and stand-up pouch composites.
CPP has excellent heat resistance.
Since the softening point of PP is about 140°C, this type of film can be used in areas such as hot-filling, steaming bags and aseptic packaging.
Coupled with excellent acid, alkali and grease resistance, it makes it the material of choice in areas such as bread product packaging or laminated materials.
Its food contact safety, excellent presentation performance, will not affect the flavor of the food inside, and can choose different grades of resin to obtain the desired characteristics.
Post time: Jul-03-2024
