The main characteristics of pearl paper

Pearlescent paper is actually coated with a layer of pearlescent pigment on the ordinary film, so that the film has a charming pearl-like luster. Commonly used films such as BOPP, OPP, PET, PVC, PE, PP, etc. Pearlescent paper is mostly composite film. Common composite structures include BOPP/BOPP (pearl), BOPP pearlescent/PE (CPP), etc. The production can be dry Compound and other methods. When dry composite pearl paper, BOPP pearl paper is generally used as a composite material and has good heat sealing performance. In the production of dry composite pearlescent paper, attention should be paid to the control of film tension and flatness, the selection of suitable adhesives, and the control of compounding temperature, etc., to prevent problems such as poor peel strength of pearlescent paper composite products. In addition, pearlescent pigments have certain requirements for film production. For example, the thickness of the film is generally very thin, and it is easy to be transparent or translucent. An appropriate amount of opaque pigment and titanium dioxide must be added to achieve a certain coverage rate. In principle, when using pearlescent pigments, avoid adding the above-mentioned pigments to avoid affecting the pearlescent effect. This seems contradictory. In fact, when producing pearlescent paper, a certain amount of titanium dioxide is often added in conjunction with pearlescent pigments to make up for the lack of film thickness. And because the film thickness is very thin, it is easy to arrange the pearlescent pigment flakes neatly and exert the pearlescent effect, but the concentration of pearlescent should be increased accordingly, about 4% to 5%. In short, when producing pearlescent paper, it is necessary to consider a certain coverage rate and meet the requirements of pearlescent effect. It is best to use a double-layer blown film machine to produce pearl paper. The upper layer is mixed with pearlescent pigments, and the lower layer uses ordinary opaque pigments. In this way, pearlescent paper with ideal effects can be produced without increasing the concentration of pearlescent pigments.

At present, the demand for pearl paper used in packaging and trademark printing is increasing. Whether it is used in PVC, PET, PE, PP pearl paper for commodity packaging and trademark printing, it has a good effect. In addition to its beautiful appearance and strong decoration, it also has excellent barrier properties. For example, in the packaging of cold drinks, most of the previous primary packaging forms of single-layer plastic films have been eliminated, and they have gradually moved to high-end multi-layer, functional (such as barrier properties, ultra-low cold) and pearlescent paper with pearl luster. package.

The production of pearl paper is generally made of polypropylene resin as raw materials, calcium carbonate and pearlescent pigments are added, and the mixture is biaxially stretched. Because of the mechanical foaming method, the specific gravity of pearl paper is only about 0.7, while the specific gravity of PP is about 0.9, so flexible packaging companies are willing to choose it because of its low price, good decoration and excellent performance. If you want to make a heat-sealed bag with good peel strength, it must be laminated, that is, laminating. In the actual production process of pearl paper, the particulate calcium carbonate masterbatch is uniformly dispersed in the homopolymer PP. When the PP is stretched, many holes are formed. It is these holes that refract light and form the pearlescent effect.

In addition to heat-sealable pearl paper BOPP, there are also three-layer copolymer non-heat-sealable BOPP pearl paper, that is, two layers of homopolymer PP with a pearl layer. In fact, BOPP pearlescent/LDPE (CPP) composite is often used to meet our requirements. BOPP pearl paper has a silvery white pearl color, which can reflect more light, and its gas barrier properties and water barrier properties are also better than other types of BOPP films.

The double-sided heat-sealable pearl paper BOPP with a thickness of 3μm can be directly used for ice cream, ice cream and other cold beverage packaging, and can also be used for candy pillow packaging, chocolate, and soap packaging. The double-sided heat-sealed BOPP pearlescent paper with a thickness of 30μm is widely used in the packaging of biscuits, sweets, candies, and flavored snacks. In addition to the application of BOPP pearlescent paper in soft packaging, a considerable part of it is used in gift packaging. A small exquisite ribbon can express friendship. The widespread use of pearlescent paper in cold drink packaging is mainly related to its economical use and its own characteristics.