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PConline talks about the fact that we live in an era of rapid technological progress. Every day, numerous new technologies are born. This is also an era of information explosion. Many manufacturers introduce new terms when they release new products, such as XXX technology, XXX technology, etc. A lot of words we can't read fill in the marketing advertisements everywhere. Not long ago, a certain brand on the microblogging for the new rice cooker propaganda warm-up, released a "buckle meal" video. In the video, the inside of the rice cooker filled with cooked rice is buckled, and a full pot of rice is smoothed out. There is almost no adhesion in the pot wall. The official website of the brand introduces "Daijin PFA food grade powder coating material" so it can be made non-stick.
The term “black technology†has been used badly. Many not-so-new technologies have been used as marketing gimmicks after being dubbed different titles. For example, “space water cooling technology†applied to mobile phones last year was indeed used for satellite cooling. However, users discovered after dismantling that the so-called “space water cooling technology†is actually a heat pipe technology that has been widely adopted on notebook computers.
Similar to "space water cooling technology," PFA is a high-end vocabulary that has never been seen before. Based on the attitude of seeking knowledge, Xiao Bian went to check on the data and found that we actually used it for many years. Saying that PFA people may feel strange, but if you say "Teflon coating," everyone should have heard of it.
Yes, PFA's full name is "tetrafluoroethylene-perfluoroalkoxyether copolymer" is a kind of Teflon coating, Teflon this name is commonplace in the kitchen advertising ten years ago, except for a few high-end products In addition, most of the current non-stick pans still use Teflon coating. What is the ghost of Teflon coating? How to make it non-stick? Why can't I see this name now? Now, follow the footsteps of Xiaobian, let us explore the past and present life of Teflon materials together.
Past World: The Beauty Brought by Accidents
The pot is an indispensable cookware in our lives. Although in the long history, the shape of the pot has always maintained its basic form at the very beginning, but with the continuous development of social economy and science and technology, the pot making process, materials, However, earth-shaking changes have taken place.
In 1938, Roy Planck of the American DuPont company accidentally discovered polytetrafluoroethylene (PTFE) when studying refrigerants. Because of its outstanding corrosion resistance and extremely low friction coefficient, it was used to seal UF6 gas in the Manhattan Project. In 1944, all hydrocarbon resins developed by DuPont were collectively known as Teflon, including polytetrafluoroethylene, polyfluorinated ethylene propylene, and various copolymers. The registered trademark (Teflon) was used to start Teflon materials. Commercial roads.
Due to the excessive heating of poorly ventilated materials at the time, toxic gases may be generated. Therefore, Teflon was mainly used for anti-adhesion in the chemical industry and other fields at the initial stage of commercial use. DuPont did not consider its use in the consumer kitchenware market. After continuous optimization, it was not until 1956 that a large-scale production of non-stick pans began in France.
The Teflon material has excellent physicochemical properties. First, it is not tack-free. Even substances with strong adhesion are easily removed. The same heat resistance and tantalum cooling performance are also prominent. They can be in the range of -200°C to 260°C. Use; friction coefficient is only 0.05 ~ 0.2; acid, alkali, salt, boiling water. Therefore, the molecular periphery of the previously-known “Teflon-repellent, non-tacky Teflon†polymer material is fluorine atom, and almost all substances are repelled, even if the adhesive is difficult to adhere to it. Attached, this is the secret of the smooth surface of Teflon.
In the last century, the prevalence of Teflon-based non-stick pans reached over 90% in developed countries such as Europe, America, and Japan. In the 1980s, I had introduced non-stick pans to the production of non-stick pans. Later, under the promotion of the major cookers, the non-stick pans began to spread in the country at an unexpected rate. According to estimates, the 21st century The annual consumption of domestic non-stick pans has reached RMB 450-450 million for three years.
At that time, Teflon's LOGO was widely seen in TV commercials and product packaging. The well-known domestic brands such as "ASD" and "Supor" all indicated that they had adopted DuPont's Teflon surface.
Crisis chapter: set dead and born
The history is always surprisingly similar. After the popularization, the problems often came. On November 15, 2003, the CCTV News Network reported that no researchers had discovered that it was widely used to make non-stick Teflon. The use of human carcinogens should be developed as soon as possible new non-stick technology or materials.
On July 8, 2004, the United States Environmental Protection Agency (EPA) filed an administrative charge against DuPont, claiming that a chemical called PFOA used at a factory in Virginia violated federal reporting requirements regarding potential health risks. PFOA is just an irreplaceable surfactant for Teflon material production.
After the news spread, it quickly caused a great uproar in the country. The major media, including CCTV, tracked the incident. Market feedback shows that not only all non-stick products are affected, but some malls will even be used. The "Teflon" non-stick pan removed the container, and some consumers also asked for a return. A crisis that began with "Teflon" began to spread.
On October 13, 2004, China's General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) concluded that most of the non-stick pans on the market had been tested and concluded that "no PFOA was detected in all tested non-stick pans."
At this point, the crisis came to an end. However, for the cooking companies, the storm still appeared to be "some fierce." This incident caused a huge loss to the entire domestic non-stick cooking industry, which made the non-stick cooking equipment market into a downturn. According to the data from the China Hardware Association, the accumulated inventory of domestic major manufacturing enterprises exceeded RMB 100 million in the year, of which ASD and Supor's backlog amounted to RMB 30 million and RMB 20 million, respectively. Many people still talk about Teflon discoloration and are afraid to even use non-stick pans.
This life chapter: I'm still me, is a different color fireworks
The development of anything is always going through some twists and turns. Although in the past decade, the term Teflon is no longer mentioned, the development of non-stick cooking utensils has never stopped, and organic coating materials have undergone countless improvements. Most of the security risks have been solved. At present, organic coatings widely used on the cookware market include PTFE, fluorinated ethylene propylene copolymer (FEP), and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA).
Theoretically speaking, as long as it is a regular source, no matter which kind of coating has good non-stickiness, all of them are in compliance with food-grade standards. As long as it is used reasonably, it will not cause harm to the human body.
Even so, due to the uneven quality of the business, when buying non-stick cookware products, we must still polish my eyes and observe the surface quality of the non-stick layer. The surface should be smooth, uniform color, no bubbles, no fall off, no obvious defects such as dirt, cracks, and explosions. In addition, products from well-known enterprises should be selected to avoid buying products that use inferior paint to impersonate food grade coatings. Of course, reasonable Land use is also very important.
Teflon's non-stick coating has won the favor of the women because of its proper physicochemical properties. However, these attributes have also brought crisis to them. Technology is still advancing. Ceramic coatings, biomimetic materials, physical non-stick and other non-stick, safer and more effective technologies have been continuously developed. However, any technology is not perfect at first, and it needs to be constantly optimized and improved in practice and application.
The technology itself is not right or wrong. However, if it is used as a marketing gimmick when the technology is not yet mature, it is not responsible to users and consumers. We want to popularize relevant knowledge for consumers, but also hope to produce On the basis of guaranteeing quality, manufacturers will further strengthen consumer tips and mop up users as monkeys.
I am the sea, we see you next time~
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