Ceramic Mug Group, Lead, cadmium dissolved amount of control work is essential for daily-use ceramics quality management center, is to do a good job of daily-use ceramics product quality and use the key to safety. Through the daily use of ceramic products lead and cadmium dissolved detection, timely detection of lead, cadmium products exceeding the standard, to eliminate the credibility of the enterprise and consumer safety to bring hidden danger, in order to improve the enterprise economy And consumers use the safety of the hidden danger, in order to improve the economic efficiency of enterprises and social credibility. This paper discusses the importance of lead and cadmium dissolution control of daily-use ceramics, especially
ceramic coffee mugs, and points out that lead and cadmium dissolution control is a daily-use ceramics quality control and ensure the safety of consumer use. Quality control and ensure the safety of consumers to use the key.
1. Introduction
Human life is inseparable from daily-use ceramics, such as
tableware, tea sets, ceramic pots and pans, ceramic coffee mugs, storage jars, etc. Throughout all aspects of human life, so the quality and safety requirements of daily-use ceramics are getting higher and higher, the products should not only be beautiful and durable, but also more importantly, the use process should not affect people's health. Is not only beautiful, durable, more importantly, the use of the process can not affect people's health and safety, which requires daily use of ceramic production process, to strictly control the amount of lead, cadmium dissolved off. As we all know, China is the birthplace of ceramics, after the reform and opening up, the rapid development of this traditional industry, daily ceramics production and export volume according to the world's first. Daily-use ceramics production and exports according to the world's first, but in the quality control, especially lead, cadmium dissolution control compared with developed countries there is still a gap, in order to improve product quality, it is necessary to strictly control the amount of lead, cadmium dissolution.
2. Daily ceramics lead, cadmium dissolved in the amount of origin
2.1 daily ceramics lead, cadmium on the human body harm discovery
In the nineteenth century, a country in Western Europe, a strange disease, patients often have paroxysmal abdominal cramps, neuralgia, anemia, intelligence and the ability to identify the symptoms of decline. Doctors and scientists analyzed the symptoms and found that it was caused by lead poisoning. Because the local people are accustomed to drinking yogurt, and yogurt is Because the local people were used to drinking yogurt, which was often served in earthenware pots containing lead, the lead slowly dissolved into the yogurt, and the people drank it for many years, leading to chronic lead poisoning.
After this incident spread, the health departments of many countries analyzed the surface of ceramics. Through the analysis, it was found that in addition to lead, cadmium is also a harmful element. Cadmium poisoning manifests itself in the form of headaches, chest tightness, coughing, weakness and other symptoms. Therefore, many countries for ceramic products So, many countries for ceramic products, especially
ceramic mugs, coffee cups, tea cups, ceramic tableware, ceramic jars, etc. to make the lead, cadmium dissolved in strict limits.
2.2 The origin of lead and cadmium dissolved in daily-use ceramics
People have found that ceramic decoration containing lead, cadmium high, not necessarily lower than the lead, cadmium-containing contaminated food serious; and the severity of contamination of food, in addition to the decoration of lead, cadmium content, more importantly, is related to the acid corrosion resistance of the food contact surface, acid resistance Strong lead and cadmium is not easy to be dissolved, but also not easy to contaminate food. So people imitate daily life, with commonly used vinegar at a certain temperature to soak ceramic tableware or ceramic coffee mugs, and then test the soaking liquid in the lead and cadmium content. Because the lead and cadmium content of the test is soaked with vinegar Because the lead and cadmium content of the test is leached with vinegar, it is called the amount of lead and cadmium leaching.
3. Control of lead and cadmium dissolved in daily-use ceramics
3.1 Raw material selection of flower paper, pigment and glaze
3.1.1 Reduce the paper, pigment, glaze lead and cadmium content in raw materials. Choose large factories, quality-assured raw materials. Reduce the area of flower paper.
3.1.2 Improve the acid corrosion resistance of the flower surface, glaze; printed on a layer of glass coating on the flower paper (commonly known as lead, cadmium protective layer), to enhance the acid corrosion resistance of the flower paper.
3.2 Production process control
3.2.1 can be improved by increasing the fineness of the glaze and pigment, so that between the particles become smaller, so that the color layer is flat and thick, after firing can be formed into a relatively tight vitreous, thus improving the
Acid corrosion resistance of flower paper and glaze. Ultimately reduce the amount of lead and cadmium dissolved.
3.2.2 To have a good quality of flower paper, glaze, to avoid the lack of glaze, pores, cracks, scratches and other defects.
3.2.3 To have a reasonable firing system. Including: firing temperature, firing gas, kiln pressure, kiln ventilation and so on.
3.3 Remedial measures for products with excessive lead and cadmium dissolved content
3.3.1 Reduce the amount of lead and cadmium dissolved through secondary firing.
3.3.2 Use chemical methods to reduce lead and cadmium dissolved. Such as using 4% acetic acid to soak the flowers and glaze for 24 hours; or 4% nitric acid to soak the flowers and glaze for 10 hours.
4. Daily ceramics lead, cadmium dissolved detection
4.1 Detection principles
For the contact surface of ceramic products in contact with food and contact with the mouth, with 4% acetic acid solution at a certain temperature, soak (or boil) for a certain period of time, extract the soaking solution, with atomic absorption spectrophotometry for determination.
4.2 Extraction of lead and cadmium from ceramic products
4.2.1 Lead and cadmium extraction of boiled products
Inject distilled water into the steaming products to 2/3 of the capacity, cover the lid, heat to boiling, add acetic acid to a concentration of 4% (v/v), maintain a low boiling for 2 hours, if a reduction in the extract occurs, replenish to the original addition of the scale. After waiting for 2 hours, the extraction solution was cooled to room temperature.
4.2.2 Extraction of lead and cadmium from flat products
4% of the acetic acid extract into the flat products to the mouth edge of 5mm, for the mouth edge of 5mm within the products with decorations injected into the decorative place, covered with borosilicate glass, immersed in the environment at 22 ℃ for 24 hours, but also some countries use room temperature immersion for 22 hours.
4.2.3 Ceramic coffee mugs of lead and cadmium extraction
Ceramic coffee cups, ceramic mugs and other hollow products of lead and cadmium extraction with flat products.
4.2.4 Lead and cadmium extraction on the edge of the products
Take borosilicate glass containers, the diameter of which is 1.25 to 2 times the diameter of the sample under test. The sample to be measured upside down into the container, inject 4% acetic acid solution to the sample to be measured from the mouth of the edge of the 20mm, placed at 22 ℃ for 24 hours, in order to prevent evaporation, plus a lid, such as the loss of extraction solution, then replenish the liquid. If there is a loss of extraction solution, make up the solution.
5. The importance of daily ceramics lead and cadmium dissolution control
5.1 Ensure the safety of consumer use
Ceramics containing lead and cadmium can cause lead and cadmium to leach into food and enter the body if they are used to hold food, especially acidic food. Lead and cadmium are heavy metal elements, easy to enter the human bloodstream and not easy to be eliminated from the body. Long-term consumption of food containing lead and cadmium will have an impact on the human immune system. Long-term consumption of food containing lead and cadmium will have an impact on the body's immune system, leading to the emergence of a variety of diseases. By strengthening the control of lead and cadmium in daily-use ceramics to prevent excessive lead and cadmium dissolved products into the market, we can avoid the hazards of lead and cadmium in daily-use ceramics on the human body.
5.2 Important means to maintain the safety of import and export trade
Daily-use ceramics is China's traditional export commodities, China's daily-use ceramics exports in 2022 was 4,884,500 tons, the main export countries are: the United States, Vietnam, South Korea, Germany, Britain and other countries; the country's requirements for daily-use ceramics lead and cadmium dissolution are becoming more and more stringent, lead and cadmium dissolved products out of the market with excessive lead and cadmium. Dissolved lead and cadmium products out of the country, light will be returned, claims, heavy will be the entire production enterprise reputation, industrial reputation has a bad influence. Therefore, only strict control of daily-use ceramics lead and cadmium dissolved in order to eliminate the outflow of unqualified products, in order to safeguard the Chinese Daily-use ceramics export security.
5.3 Effective means to improve economic efficiency
We all know that the quality and safety of products is the fundamental of long-term development of enterprises. If the quality and safety is not good, it is difficult for enterprises to go the long term. For daily-use ceramics, the improvement of people's living standards, driven by the development and growth of this industry, the expansion of the market scale Expansion of the market size to bring greater competitive pressure, the pressure of competition are concentrated in the quality and safety of products, product prices and service levels. For daily-use ceramics, lead and cadmium dissolved is the most important factor in product quality and safety, any deviation from the safety of lead and cadmium dissolved daily-use ceramics Any factory that deviates from the safety of lead and cadmium dissolved in daily-use ceramics will surely fail in the market competition.
6. Summarize
Daily-use ceramics lead and cadmium dissolved control, is the key to good or bad product quality. Enterprises through the control of raw materials, production control, lead and cadmium detection, strict control of all aspects, so as to control our production of ceramic products of lead and cadmium dissolved. To be in the vast To stand out in the vast competition, we must carry out technological innovation, pay attention to the control of lead and cadmium dissolved, strict quality control, to avoid the inflow of unqualified products into the market, to maintain the safety of China's ceramic products, in order to allow the world to rest assured that the use of our ceramic products.
