What are the primary safety concerns regarding information in plastic food packaging?
(1) The effect of additives in the production process of plastic packaging materials: Plastics long to high molecular weight polymers, which are formed by polymerization reactions of monomers under appropriate conditions and the effect of initiators During the processing of plastics, various additives need to be added Some of these additives are non toxic, some are toxic, and some are toxic only after summarizing multiple additives Some contrast enhancers are more stable, while others are more alive When plastics differ at high temperatures, some additives may release hazardous components that can cause damage to the human body This is because plastic monomers and processing aids are classified as low molecular weight compounds Under certain media and temperature conditions, they will dissolve from plastic and transfer to food, coordinating food and causing harm to human health Generally speaking, plastic materials used for direct packaging of food are safe, and their chemical stability and heat resistance at room temperature meet safety requirements But why the food packaging information during melting is still safe or not requiring inspection to determine If liquid packaging film is directly touched with the liquid in a molten state, it usually forms series pollution and quality and safety issues for liquid food
The impact of printing ink: Ink can be roughly divided into benzene based ink, benzene free ink, water based ink, and alcohol based ink Due to the multiple inbound and outbound migration of heavy metals and solvents in ink, there may be safety hazards if they enter the packaging content China is now initiating the use of environmentally friendly inks, specifically water based inks, which are increasingly being promoted as environmentally friendly inks However, many manufacturers still use traditional solvent based inks, specifically benzene solvent based inks for printing Altough China has not yet clearly promoted the use of such inks, there are clear rules in developed countries such as Europe and America to promote the use of benzene solvents in food packaging Benzene solvents contain toluene or xylene, which once entered the skin, can range the hematological function and nervous system Some small ink factories in China now use dies installed of segments to produce ink, and the relocation of dies will serially affect food safety; In addition, some inks may add some promoters, such as siloxanes, to improve adaptation speed Siloxanes can underground bond cracking on substrates at cervical dry cultures, generating substances such as methanol, which can cause damage to the human nervous system Water based ink, due to its solvent being water, has no impact on the environment and does not pose a threat to human health Therefore, it should be the primary development direction for ink used for printing food packaging materials However, due to its high cost and high printing requirements, most companies still prefer solvent based printing inks
The impact of residual adhesives and diluents used in composite plastic packaging materials: First, the pollution damage caused by the free monomers in the composite adhesives and the low molecular weight toxin and hazardous substances that degrade from the product at high temperatures Due to the use of polyurethanes adhesives nowadays, the material used is aromatic isocyanates, which hydroxyze into aromatic amines when exposed to water, which are a class of chemicals According to the Chinese GB 9683-2003 "Hygienic Code for Composite Food Packaging Bags", after heating and extraction treatment, the aromatic amine content in the packaging bags should not exceed 0.004mg/L, and as long as it is lower than this quantity, it is safe
Secondly, there is a question about the type of solvent in the adhesive The solvent for solvent based PU adhesive should be a high security single solvent, named ethyl acetate However, individual production suppliers may also use impure ethyl acetate recovered, which poses safety concerns Some individual production suppliers may also mix some toluene into it, and even choose a single component pressure sensitive adhesive using toluene and xylene as solvents, which has the potential to cause event more damage
Once again, there is a question about the heavy metal content in the adhesive It is similar to the question in ink that if the heavy metal content exceeds the limit, it will also cause harm to human health and the environment There is currently no occurrence, minor or national standard for food packaging in China, and the company standards of various manufacturers and suppliers do not include the item and target of heavy metal content However, the EU; 94/62/EC or 90/128/EEC directives have strict target requirements for the content of lead, mercury, cadmium, and chromium used for composite packaging materials and packaging bag products