New trends in composite flexible packaging in the international food market

With the development of industry and the need for consumption, people hope that the future food industry products, especially health foods, will have a longer shelf life. This requires the development of composite packaging in terms of serialization, multi-functionality, high performance, and special functions.

Paper-based composite packaging: This is a kind of composite flexible packaging, mainly including film type, liner bag type, embedded type, and liquid type. The main challenge of paper-based composite packaging is to solve the problem of imperviousness, because oil molecules are extremely small. As Japan developed a boxed cooking oil compound carton, very successful. The structure of the composite paper is PE/paper/PE/AL/PET/PE, and the paper is made of aluminum-plastic 6-layer composite. As the composite layer has aluminum foil, its performance is better than that of glass bottles and plastic bottles. It is both safe and lightweight, and it is beautifully printed, which increases the added value and competitiveness of the goods.

New composite "paper": Super-strength composite paper has been successfully developed abroad. The paper is as white as snow, as thin as a flap, soft as brocade, still intact after repeated folding, also known as soft glass, and low prices. This kind of “paper” is drawn into fiber with basalt at a high temperature of 2000°C, impregnated with phenolic resin and infiltrated with white clay to make a film. Because of the rock-based material, long-term storage will not become brittle, moldy, and insect-like, and it can be printed in color and used widely. In addition, there are dust-free paper, sterilization paper, anti-odor paper, anti-charged paper, anti-electromagnetic interference paper, high absorption paper (ie, stealth packaging materials) and so on.

Deodorant packaging

Due to the development of supermarkets and fast-food restaurants and the emergence and popularity of a new concept of HMR in recent years, the HMR market has developed rapidly. In order to prevent the effects of odors (refer to odors and odors) on packaging items, deodorant packaging was developed. Now there are more than 40 kinds of deodorant packaging materials, mainly divided into three types: A type of chemical deodorant type, can remove nitrogen compounds and sulfur compounds plus ammonia, dimethylamine, trimethylamine, hydrogen sulfide and other odors Or smell.

Class B is a physical type and is mainly used to remove odors or odors such as hydrogen sulfide and carboxylic acids. It is characterized by a good deodorization effect on high concentrations of hydrogen sulfide.

Class C materials are mixed deodorant types. It is mainly made of activated charcoal deodorant. Good deodorizing power at low concentration is the characteristic of this type of material.

Deodorant packaging film for food packaging can also play a role in deodorant preservation. General deodorant packaging is mainly used for those foods with special odors or odors, as well as packaging for agricultural products and aquatic products.

Antibacterial packaging

The problem of food corruption caused by microorganisms has made antimicrobial packaging a hot topic. To this end, Japan added a new type of inorganic antibacterial agent to packaging materials and developed a series of successful antibacterial packaging materials, which have antibacterial effects on various pathogenic bacteria. The main characteristics of the packaging material are as follows: The antibacterial effect lasts for a long time; because the antibacterial agent is a gas phase type, it has no adverse effect on the contents of the package; the stability is good.

In the packaging process, it has high thermal stability, stable concentration, and no adverse effects on the operating environment. Antibacterial packaging materials mainly include sheets, absorbent sheets, packaging films, and antibacterial packaging papers. The sheet is a mixture of antibacterial agents to polyolefins.

Pressed in the resin, the water-absorbent sheet is made of super absorbent resin as the substrate, usually with sheet type and coating type. Such as non-woven / paper / water-absorbing resin mixed with antibacterial / paper / non-woven fabrics.

Currently widely used is the antibacterial packaging film, made by adding antibacterial agents to the polyolefin film, and has antibacterial effects on most common microorganisms such as coliform bacteria, Staphylococcus aureus, Phytophthora boehmeriae, Borreiella aureus, and Aspergillus niger.

High barrier packaging

As we all know, the performance of aluminum-plastic composite packaging materials is superior, but it is opaque. For this reason, experts have successfully developed a class of high-barrier new materials. Its good barrier properties, other properties equal to or better than aluminum plastic composite materials. This kind of composite packaging material called GT is made by depositing a film of inorganic material (such as nano-silicon oxide or titanium oxide) with a thickness of 10 to 100 μm on the surface of the plastic film. This kind of nano coating has stable performance. Even after high temperature sterilization, its gas barrier property, moisture resistance and transparency are still as it was.

In recent years, the United States has successfully developed a thermo-effect liquid crystal polymer film (TLCP) consisting of a special dense, long-chain fibrous polymer with good strength and toughness. The gas barrier performance of a 2um thick liquid crystal polymer is equivalent to 25um thick EVOH, but the price is much lower than the latter.

Low temperature sealed packaging

Packaging machinery should be simple and convenient, save energy, increase speed, increase efficiency, to meet the needs of modern high-volume packaging, so the use of low-temperature sealing packaging materials is a necessary condition for low-temperature sealed packaging. The so-called low-temperature packaging material is a layer of low-temperature cold-sealed coating that is coated with natural rubber as the main component on the surface of the film, and does not need any heat to seal the packaging material. It has a series of characteristics: First, it has no thermal impact on the contents of the package, so it is particularly suitable for the packaging of heat-repellent products; second, it can use hard-sealable substrates; third, it can simplify the packaging machinery, reduce costs and save energy. The fourth is to achieve high-speed packaging; Fifth, the seal is good cold resistance, even at -20 °C seal strength does not decrease.

High-speed sealing packaging

The requirements for flexible packaging are mainly stylish and inexpensive. For example, the packaging of products such as chocolate, due to the influence of heat, requires a low packaging temperature and a beautiful seal. For this reason, high-speed sealing packaging materials have been developed. This is a packaging material coated with high-speed heat-sealable HSS and capable of high-speed sealing at low temperatures. It is superior to other materials such as EVA, acrylics, heat-sealing varnishes, trace waxes, etc., and therefore can be used for packaging of products that strictly limit the influence of odors or odors. Its characteristics are fast sealing speed, suitable for high-speed machinery. If using OPP/KOP/HSS packaging materials, the speed of the three-party bag making machine can reach 500/min. HSS can not only be coated on the surface of paper and aluminum foil, but also coated on the surface of various plastic films such as PP, KOP, PET, PVC, PE, etc. Generally, the thickness of HSS coating is about a few microns to meet the requirements.

Composite plastic packaging

After China's accession to the WTO, due to the reduction of tariffs, the import tax on plastic resins will drop by 60%. The plastic packaging industry in China will have more room for development, and the food flexible packaging industry will have better development prospects. Polyester: At present, 77% of global bottle polyester resin is used for food packaging, and non-food packaging only accounts for 23%. Food packaging is mainly carbonated beverage bottles, accounting for about 50% of the total. 21% of other beverages are packaged, and about 6% are consumed in edible oils and salads. In the past five years, the annual growth rate of polyester bottles reached 18%. With the improvement of people's living standards, the demand for packaging materials is also increasing, and polyester packaging containers just meet this requirement. Especially in beverage packaging, PET bottles have gradually replaced PVC bottles, tin cans, and aluminum cans with their excellent performance.

PVC: In recent years, with the improvement of people's living standards, various convenient, health care, medical, and flavor foods will become the development direction of the food industry. In order to meet the market's development, we must produce more high-barrier single membranes and composite membranes to meet the requirements of various steamed food packaging and aseptic food packaging. The anti-mildew and pest-proof packaging of food, fresh-keeping packaging of cakes, preservation of vegetables and fruits, long-term frozen food packaging, microwave food packaging are all huge markets for polyethylene packaging materials.

CT Materials: After 10 years of hard work, the Japan Central Chemical Company has successfully developed a plastic CT for food packaging containers that meets the environmental protection principle. The surface of the vessel made of CT plastic is not much different from other food packaging containers, but the internal quality is greatly changed. According to experts, this kind of plastic is filled with about half of the amount of talc powder produced in Liaoning Province of China from polypropylene plastics and blended to make new composite materials. CT is not only resistant to high temperatures, but also has one of the most prominent advantages, that is, its function is similar to the PSP plastic product commonly known as “foam foam plastic”, and its volume is only equivalent to 1/4 of the latter. In this way, many troubles caused by the bulkiness are avoided during recovery, and extremely favorable conditions are created to eliminate the negative impact on the environment.

Sterilized absorbent food bag: The Russian Institute of Applied Technology recently developed a food packaging bag that can absorb water, sterilize, and can be reused many times, enabling foods that are easily deteriorated, such as cheese sausages, to be stored for a longer period of time. Russian experts have added dehydrated mineral salts and enzymes to food packaging and packaging polymers.

Corn Plastics: Not long ago, U.S. researchers developed a corn plastic packaging material that was easily decomposed. It extracts three kinds of genes that can produce plastics from the bacteria that make biopolymers, and then transfers them to the rapeseed plants. After a period of time, it produces a plastic polymer liquid that can be obtained after being refined. Seed plastic. The packaging tree or food fast food packaging material made of this plastic can be decomposed by itself after being discarded without contaminating residues.

Wheat plastic: This is the use of wheat flour added glycerol, glycol, polysilicone mixed dry, then hot pressed into a translucent thermoplastic plastic film. The advantage of packaging foods with wheat plastics is that they can be decomposed by microorganisms.

Bacteria plastic: British researchers recently developed a PHB bacterial plastic. It uses sugar to grow a kind of bacteria, and then it is processed to make it similar to polypropylene. This material is non-toxic and easy to biodegrade. It is an ideal material for processing food packaging bags. At the same time, there is no pollution to the environment after abandonment.

Functional packaging

We know that the use of composite functional materials is more economical and reasonable than the use of composite functional materials in part, so the industry has developed a variety of functional packaging materials. Common anti-rust type, anti-discoloration type, pest control type, anti-mildew type, preservation type, nano-type and so on.

Due to people's requirements for modern life, fresh-keeping packaging has developed rapidly. There are more than 100 kinds of fresh functional materials that have been successfully developed.

Smart packaging

The so-called smart packaging refers to the packaging that has "identification" and "judgment" functions for environmental factors. Currently developed smart packaging, usually using photoelectric, temperature sensitive, humidity sensitive, gas sensitive and other functional materials, packaging materials composite. It can identify and display some important parameters such as temperature, humidity, pressure, degree of sealing, and time of packaging micro space. This is a very functional packaging that is promising, and is particularly important for packaging products that require long-term storage.

Green packaging

In the green environmental revolution, packaging waste generally adopts recovery, reuse, and fuel oiling technologies. However, for flexible composite plastic films, classification, recycling, and reuse are still a major problem, and combustion or landfill treatment is used. Emissions of harmful substances such as dioxide or heavy metals are still polluting the environment. To do this research abroad, developed an environmentally friendly film.

In this eco-friendly film, since active oxides are added, waste combustion is promoted on the one hand, and on the other hand, the production of dioxide is reduced, and also reacts with heavy metals to effectively prevent the residual ash. The dissolution of heavy metals is known as "clean film" and attracts attention.