Food packaging film is used to wrap the surface of the food, mainly used to isolate the decomposition of microbial bacteria and foreign pollutants into the prevention and extension of food deterioration of the polymer material. Food Antibacterial Packaging is the most promising part of food active packaging. The choice of antibacterial film packaging is the most beneficial, it can continue to release antibacterial agents to inhibit the growth of microorganisms to ensure food safety, extend the shelf life of food. Let us consumers enjoy a higher quality of life.
There are many ways to prepare food antibacterial packaging films. One is to prepare antimicrobial masterbatch by antibacterial agent or antimicrobial masterbatch and resin monolayer, or by co-extrusion as a surface layer and other layers to form an antibacterial composite film. And one by coating or depositing the antimicrobial agent on the resin film.
For the antibacterial film prepared by the antibacterial masterbatch, since the film itself is thin in thickness, it is required that the particle size of the antibacterial particles is small and is distributed by a narrow particle size or an organic antibacterial agent capable of being dissolved in the resin. The effect of the addition of antibacterial or antimicrobial masterbatch on the mechanical properties of the film is not very obvious, and the printing performance of the film is not adversely affected. But some of the film's barrier properties have a certain impact, so the choice of antibacterial agents and antimicrobial masterbatch should pay attention to antibacterial agents and antimicrobial masterbatch to join the film on the performance of the situation, select the appropriate antibacterial agent to ensure the performance of packaging Meet the requirements. General use of packaging materials are LDPE, LLDPE, EVA, cellulose film, edible film and so on.
For the method of coating or depositing the antimicrobial agent on the film, the gap between the different plastic self-barrier properties is large and the quality of the final product can be affected if the substrate is damaged during coating and coating. The surface properties of the surface of the plastic film, the performance of polarity, surface roughness, surface oxygen, nitrogen atoms will affect the percentage of film and antibacterial adhesive strength, thus affecting the antibacterial properties. In addition, the surface of the film substrate should be pretreated before the antimicrobial agent is applied or deposited onto the film, and the surface land energy can be improved and the bonding force can be improved. For the coating or evaporation of the packaging film substrate generally PET, PA, PVC, BOPP, LDPE and so on.
In addition to satisfying the mechanical properties required for the packaging itself, the printing performance, the display properties and other packaging materials must have the performance, the world's food for the packaging of food products have high health requirements. China's national standard GB-9687 provides for the health requirements of food packaging materials, requiring material color normal, no smell, no smell, no foreign body, and in the evaporation residue, potassium permanganate consumption, heavy metal content, decolorization experiments Aspects meet the corresponding requirements. The United States FDA on the food packaging materials composition, additive specifications, conditions of use, dissolution requirements, food packaging materials, chronic toxicity test requirements, sub-chronic toxicity test requirements have also made specific provisions.