Innovation

   Barrier property is the most important characteristic of packaging materials. In particular, the shelf life of food is highly dependent on the barrier property of packaging materials. The so-called barrier material refers to the standard state (23°C, 65% relative humidity). A 25.4-micron-thick film is a material whose oxygen permeability is below 5ml (㎡.d) and moisture permeability is below 2g/(㎡.d).

The form of packaging bag is generally divided into back seal bag, pillow bag, four seal bag, monolithic,etc.

Gravure printing, abbreviated as gravure, features thick ink layers, vibrant colors, high saturation, high print durability, stable print quality, and fast printing speed. Therefore, gravure printing has always been the primary printing method in the domestic flexible packaging printing industry.

According to adhesion theory, when the surface tension of the adhesive matches that of the substrate and their polarities are similar, the interfacial tension is minimized, resulting in maximum adhesion strength. Therefore, the surface conditions of the ink or adhesive after curing and the film surface may vary depending on the products from different manufacturers.

As practitioners, they shall have a certain understanding of the influence of temperature and humidity on the entire process of dry lamination. Here’s a summarize to let everyone deepen the understanding of the influence of temperature and humidity on the dry lamination and improve the operator's attention.

PVA coated barrier film is to coat a layer of transparent polyvinyl alcohol (PVA) on the based films of different thickness (like BOPP, PET, NY, CPP, PE and other plastic films). PVA coating makes the materials perform good barrier to O2, N2, CO2 and other gas or small molecule volatiles, which is mainly used to improve the gas resistance performance of flexible packaging materials and plays a protective role in the contents with high fat and strong aroma, and easy to oxidation and deterioration.

      Food packaging is the main object of the use of composite flexible packaging material. It has different requirements in great diversity. The contents are packaged from raw to cooked, from low temperature to high temperature, from high moisture content to dried food, from vacuum packaging to inflatable packaging, almost covering all applications of composite flexible packaging materials. The commonly used food packaging technology are as follows.

The essence of this issue is about the dimensional stability of the film at high temperatures.

LD PACK’s packaging with MDOPE is used high density polyethylene (HDPE) as the main raw material, which has good temperature resistance and good dimensional stability.

       Due to the regional and seasonal differences in the sales of packaging bags, and some packaging bags need to be frozen and refrigerated at low temperatures (generally, the storage conditions at -30°C ~ -20°C are called cryopreservation, while at -5°C The storage condition of ~0°C is called refrigerated storage), and cold resistance (low temperature resistance) is a key characteristic of the packaging material at this time.