The color of plastic products is generally adjusted by adding color master materials during the thermal processing of plastics. The organic or inorganic colorants contained in them will not react with plastics. Good heat and so on.

The masterbatch material will not participate in various chemical reactions, especially the masterbatch material used to make food packaging, which must be absolutely non-toxic.

　　Liu Jifeng

　　Professor, School of Food Science and Engineering, Tianjin University of Science and Technology

　　This summer, the classic "green outfit" of Sprite Beverage completely withdrew from the stage of history.

From August 1st, Sprite abandoned its iconic green bottle packaging for a more environmentally friendly transparent container, thus ending more than 60 years of green bottle history.

　　As for the reason for the replacement of the packaging, the explanation given by the Sprite manufacturer, Coca-Cola, is that the material used in the green bottle is green polyethylene terephthalate (PET), but the green bottle is mechanically recycled and turned into a transparent bottle. The cost is high and the process is complicated, while transparent plastic bottles are easier to recycle, which can reduce plastic waste.

　　Beverages "wearing colorful clothes" are easier to be remembered by consumers

　　In addition to Sprite, there are many beverages in brightly colored "coats" on the market.

　　The reason why there are so many color "prominent" beverage bottles, Liu Jifeng, a professor at the School of Food Science and Engineering, Tianjin University of Science and Technology, and Yan Ruixiang, a professor at the School of Light Industry, analyzed in an interview with a reporter from Science and Technology Daily that different colors of outer packaging will have different effects on the brain. The stimuli, and the overhanging color may better stimulate the consumer's desire to buy, and deepen the consumer's memory so that consumers can form a consumption habit.

　　Relevant research shows that consumers will make subconscious judgments about a product within less than 90 seconds of viewing a product, and 62% to 90% of them give a product evaluation based on the color of the product packaging alone.

In addition, nearly 85% of consumers say that the color of a product is an important factor in deciding whether or not they buy it, so many iconic colors are used by a specific category of product or a brand that wants to express a certain appeal.

　　Jenn David Connolly, a creative strategist for packaging design, once said that color not only affects consumers consciously, but also subconsciously. Therefore, choosing the color of food packaging and choosing its The ingredients are equally important.

　　Although the color is fancy, there is no problem with the safety of the colored bottle.

"The color of plastic products is generally adjusted by adding color master materials during the thermal processing of plastics. The organic or inorganic colorants contained in them will not react with plastics. The color master materials have strong solubility resistance, low migration, Good heat resistance and other advantages." Liu Jifeng explained that the color masterbatch material will not participate in various chemical reactions, especially the color masterbatch material used to make food packaging, which must be absolutely non-toxic.

　　The recycling and reprocessing path of green PET material is complex

　　"Sprite's previous green bottle was made of PET, which was doped with green masterbatch." Liu Jifeng said that PET has the advantages of light weight and durability, and is widely used in industrial manufacturing.

At the same time, PET also has the advantages of non-toxic, odorless, good hygiene and safety, so it can be directly used as a food packaging material.

　　"The biggest advantage of PET is that it can be recycled." Liu Jifeng said as an example, for example, recycled PET can be used to make plastic bottles, and recycled PET can also be used to make fibers, and then made into familiar chemical fiber textiles, such as sports Clothing, tents, etc.

　　Therefore, if PET is recycled well, it will not cause significant environmental pollution problems.

　　"However, green PET not only has complicated recycling and reprocessing paths, but also has limited secondary uses. The transparent and backgroundless PET has low recycling costs, a wide range of reuse fields, and high recycling value. Therefore, compared with It will be more environmentally friendly." Liu Jifeng said.

　　Besides PET, polypropylene (PP) is also one of the most commonly used materials for beverage bottles.

"Comparing the two, the recycling and reprocessing cost of PET is lower than that of PP." Liu Jifeng said that PET is often used to make mineral water bottles and carbonated beverage bottles, while PP is often used to make soy milk, dairy products, juice and other beverages packaging bottle.

　　In addition to plastic, there are these food packaging materials

　　At present, in food packaging materials, plastics (soft and hard plastics) account for a large proportion, reaching 37%; at the same time, paper packaging materials are also very common, accounting for 34%; in addition, there are glass and metal packaging materials, It accounted for 11% and 9%, respectively.

　　"Generally speaking, there are two main factors to consider when choosing food packaging materials." Liu Jifeng said, the first is to maintain food quality.

The biggest role of food packaging is to maintain food quality. Manufacturers need to choose suitable packaging according to the characteristics of food.

The second is to arouse consumers' attention and interest in the product.

Consumers form the first impression of the product through product packaging, and the outstanding packaging design can quickly attract consumers' attention and arouse consumer desire.

　　At present, the popular paper packaging is light in weight, easy to process, recyclable and highly decorative, and is often used to make the outer packaging of milk, desserts and other foods.

　　Metal materials include tinplate and aluminum, which have the characteristics of corrosion resistance, non-toxicity, high strength, good extensibility, and excellent packaging sealing, and are often used to make food packaging such as cans and tea cans.

　　Glass has excellent chemical stability and can meet the purity and hygiene requirements of food packaging. It has beautiful appearance and advantages that other materials do not have.