Application of nylon film in pet food packaging
In western countries, the “pet economy” is a huge industry. Taking pet food as an example, North America (mainly the United States) is the largest consumer market of all pet food, and it also accounts for the vast majority of sales. Western Europe is the leading consumer market for all other pet food categories, and the second largest consumer market for dog and cat food. Among them, the development of the pet economy in the United States and Japan is particularly prominent.
Problems that are prone to occur in the current market situation
In China, more and more people have pets. With the increase of the number of pets, a series of related industries have emerged around the pet economy, such as pet food, pet supplies, pet medical treatment, pet beauty industry, etc., which will have a broader market prospect. Pet food packaging will become one of the hot spots in the field of packaging in the future.
Taking pet food such as cats and dogs as an example, the raw materials are mainly meat products.
Its characteristics include the following two aspects:
In order to maintain the taste of pet food, the ingredients should not be made too soft or powdery during the production process. It is necessary to maintain the toughness and brittleness of meat, bones and fish bones. Therefore, pet food is characterized by irregular shape and contains sharp objects such as bones and fish bones.
Pet food is basically irradiated food. To extend the shelf life, pet food needs to be irradiated to sterilize. Irradiated food refers to food processed by irradiation with gamma rays produced by cobalt-60 and cesium-137 or electron beams below 10MeV produced by electron accelerators, including irradiated food raw materials and semi-finished products.
At present, irradiation technology is widely used in many countries to ensure food safety and extend food shelf life, and is recognized by more and more consumers.Like low-temperature refrigeration, high-temperature treatment and chemical treatment, this technology can remove the microorganisms that cause food corruption and food borne diseases in food.In food packaging, radiation is also a great way to extend the shelf life of food.
In aseptic packaging systems, the sterilization methods for packaging materials include ultraviolet sterilization, chemical methods and ultraviolet combined sterilization, infrared sterilization, ionizing radiation and light pulses. When a packaging material can neither pass thermal energy nor pass through Ionizing radiation is a good cold sterilization method for chemical disinfection and sterilization.
At present, the common pet packaging in the Chinese market generally adopts the packaging method of zipper three-dimensional bag. In order to improve the shelf effect and barrier performance, most domestic flexible packaging manufacturers use VMPET or AL as the barrier layer;
The problems of pet food packaging in China include the following aspects:
1. VMPET or Al is used as the barrier layer, but the products cannot be seen directly, which limits the shelf display effect of products;
2 As the products are bones, fish bones and other objects, the bag is easy to be punctured, resulting in quality problems.
3 The smoothness of the packaging bag is not good, and the opening is poor in the production process, and the production efficiency is low. At the same time, it will also reduce the utilization rate of the packaging bag and increase the cost.
4 After irradiation, the overall mechanical properties of the bag decreased.
Design idea of composite structure for pet food packaging
In actual production, irradiation has no effect on the properties of glass and metal containers, but it can reduce the flexibility and mechanical properties of plastics. Therefore, in the design process, if there is no suitable composite structure, the bag is easy to be punctured and the physical and mechanical properties of the bag are reduced. Therefore, it is of great significance to study the unique composite structure to adapt to the impact of irradiation on the properties of plastic.
Pet food packaging should meet the following requirements during the actual packaging, transportation, storage and use:
1. Good barrier performance
The products of the package are pet food, which must be able to meet the quality assurance requirements of the products, maintain the quality and flavor of the products, and have a good shelf life.
2. Good puncture resistance
It contains sharp objects such as bones and fish bones. In order to ensure that the bag is not punctured, it must have good puncture resistance.
3. Good visibility
You can directly see the products from the package to attract consumers’ attention.
4. Good stiffness
This kind of pet food is basically packaged with standing zipper tape, so the packaging material has good stiffness and can improve the shelf effect of goods.
5. Good radiation resistance
After irradiation, it can still maintain good mechanical properties.
Example of structure selection
In order to meet the above requirements for pet food packaging, we suggest that the following composite structure can be adopted:
Middle layer: BOPA film or EHA high barrier film with higher oxygen resistance
BOPA nylon is polyamide, which has excellent strength, toughness, tensile strength, elongation and wear resistance. Nylon is selected because it has good physical and mechanical properties. After compounding, it can enhance the puncture resistance, impact resistance and other properties of the product, and can protect the contents well. Recommendation: Changsu BOPA Ultrany.
EHA has ultra-high oxygen resistance (oxygen transmittance OTR is as low as 2cc/ ㎡ day · ATM), which can achieve excellent fragrance retention; Its rubbing resistance, tensile resistance and excellent compliance strength greatly reduce the bag breaking rate; And it can achieve high transparency and excellent printing effect; In addition, it is also an environmentally friendly material that will not produce toxic gases when burned. Recommendation: Changsu Supamid EHA fresh locking film.
Inner layer: PE film with improved formula
Considering the safety and hygiene of pet food, this product adopts solvent-free production process. However, the solvent-free production process will have the problems of high friction coefficient and poor openness. Therefore, in order to improve the equipment adaptability of PE, the formability, puncture resistance and radiation resistance of the bag body must also be considered. The PE formula can be improved to make it have better equipment adaptability, stiffness and puncture resistance.
BOPA nylon is polyamide, which has strong crystallinity, high melting point and excellent performance. Good toughness, tensile strength and impact strength are significantly better than general plastic film. As a middle layer in this project, it can improve the puncture resistance of PET packaging to prevent sharp objects such as fish bones from puncturing the film. Moreover, the air tightness of nylon is better than that of PE and PP, which can improve the barrier performance of packaging. At the same time, it has good oil resistance, which can be resistant to oil stain when packaging pet food of meat products, so as to avoid delamination of packaging film and decline of peel strength.
Post time: Jul-28-2022