[Office Partner Information Center] Printing paper is everywhere in our lives. However, is the paper safe, do you know?
Through a set of experiments, we found that the mask used by women has the shadow of a fluorescent whitening agent.
Experimental items: various books used by students
Experimental equipment: UV analyzer
Experimental principle: Under intense ultraviolet irradiation, the fluorescent whitening agent will automatically appear, making the paper appear blue. The darker the blue, the more the fluorescent whitening agent content, and the less the opposite, if no blue, the paper does not contain fluorescent whitening agents.
experiment procedure:
Before the experiment, we selected more than ten different types of student books in the stationery store, including the text box for the primary school students, the English version, the grass, the text, and the notebooks, manuscript papers, and notes used by the middle school students. Paper, etc., these books are very white, some are slightly yellow, and there is a book specifically for the prevention of myopia, the price is much more expensive than the ordinary book, the price is twice as high. The experiment also included printing papers that we often use in our office. We also experimented with our own interviews and placed them under ultraviolet light. The results were obvious. Only 13 kinds of papers contained only 4 kinds of papers. Brightener.
Experimental results:
Printing paper: Blue is the most obvious and brightest, indicating that it has the highest level of fluorescent whitening agent.
Primary school text (price: 5 angles): paper surface: bright white, paper is very thin. After irradiation: blue light, indicating the presence of fluorescent whitening agent.
Small notebook (price: 5 yuan): paper surface: the paper is slightly thicker and yellower. After irradiation: no blue light, indicating no fluorescent whitening agent.
Scratch pad (price: 1 yuan): paper surface: the paper is slightly thicker, especially bright white. After the irradiation: blue light, second only to the printing paper, very bright.
Big composition (price: 1 yuan): paper surface: paper is transparent, white. After irradiation: blue light, indicating the presence of fluorescent whitening agent.
External text (price: 1 yuan): Paper surface: The paper is yellow. After irradiation: no blue light.
Large square (price: 1 yuan): paper surface: the paper is slightly black. After the irradiation: a slight blue light appears, not obvious.
English version (price: 5 yuan): paper surface: the paper is yellow, slightly thicker. After irradiation: no blue light.
Manuscript paper for prevention of myopia (price: 3 yuan): paper surface: the color is yellowish green. After irradiation: no blue light.
Big note (price: 2 yuan): paper surface: the paper is slightly thicker and whiter. After the irradiation: blue light, it is obvious.
Notebook (price: 1 yuan): Paper surface: the paper is thick and bright white. After the irradiation: the blue color is obvious, similar to the printing paper.
Big calculation grass (price: 1 yuan): paper surface: the paper is very thin and the color is dark. After the irradiation: a slight blue light, only a little bit of the star, not obvious.
The field of prevention of myopia (price: 2 yuan): paper surface: the paper is slightly thicker, the color is yellowish green. After irradiation: no blue light.
Experimental conclusion: We found in the experiment that the whiter the paper, the more obvious the blue light is, the paper that is usually used is especially obvious, and the paper like anti-myopia does not contain fluorescent whitening agent, and the paper color is slightly darker. Blu-ray. Moreover, after touching these papers, the reporter's hand was also stained with fluorescent whitening agent. Under the ultraviolet light, the stars were brightly lit with blue light.
About fluorescent whitening agent
Half a century ago, a German company invented a fluorescent whitening agent. When this chemical was added to the pulp, the color of the paper turned bright white. The principle is that the fluorescent whitening agent can absorb the ultraviolet light which is invisible to the naked eye, and converts the high-energy ultraviolet light into the wavelength light of the blue color. The blue color light is released and mixed with the yellow color of the paper, and the naked eye sees the change. It becomes white, so fluorescent whitening agents are often added to white paper of higher quality.
Why do you want to add fluorescent whitening agent to your paper?
Why do you want to add fluorescent whitening agent to paper? According to Mr. Li, a worker from a printing factory in the foreign country, the fluorescent whitening agent was added to the paper to make the paper whiter and more beautiful. In the current workbooks and papers used in notebooks, the amount of non-pure pulp paper is getting larger and larger, and many papers are recycled many times. In order to look more beautiful, the addition of fluorescent whitening agents is a necessary process. The natural puree of the paper is slightly yellowish and the color is yellow, which is pure natural paper without any chemical composition, but this natural paper looks not very good, most of the white paper is more willing to be accepted by everyone. .
“If you use pure natural pulp to make paper products, the color will definitely not meet the requirements. The merchants must try their best to make the paper white when the paper is processed.†Professor Sun said that in the processing technology, things are usually changed. The white method is bleaching, and food and textile materials are often whitened by bleaching. Similarly, paper can be bleached. For example, blue pigment is added to the yellow puree and whitened when mixed. However, sometimes the paper does not reach the "white" requirement after bleaching, so it is necessary to add a fluorescent whitening agent.
Current homework for primary and secondary school students
No fluorescent whitening agent content standard
Dong Jinshi, a well-known environmental chemistry expert and deputy secretary general of the Beijing Environmental Science Society, said that there is not enough data at home and abroad to show that fluorescent whitening agents have an exact toxic effect on the human body. However, according to medical clinical experiments, fluorescent substances can cause variability in cells, and if there is excessive exposure to fluorescent whitening agents, there may be a potential health threat. Once the fluorescent substance enters the human body, if the dose reaches a certain level, it is highly likely that the cells will become cancerous. It contacts the wound and binds to the protein, preventing the wound from healing. Excessive intake of fluorescent whitening agents can cause damage to children's vision, skin, etc., especially those who are not yet mature and have relatively weak resistance.
Dong Jinshi said that there is no standard for fluorescent whitening agents in the country's workbooks for primary and secondary school students. It is recommended that enterprises use environmentally friendly paper products that do not contain fluorescent whitening agents to produce notebooks and notebooks. The state should set standards for stationery papers as soon as possible to regulate the market and protect student safety. At present, Shanghai has established the standards for the Safety, Health and Quality Requirements for Primary and Secondary School Students.
Experiment reminder
The glaring book is best not to buy
For the sake of safety, parents are advised to observe the color of the paper under bright light when purchasing the homework. If the paper is too white or too bright, it is best not to buy it. The yellowish paper is relatively safe. In addition, parents are advised to educate their children not to put their homework in their mouths to prevent the fluorescent whitening agent from being swallowed directly by the child.
Second, try not to use paper to wrap things. For example, many people like to use paper-based fritters, pancakes and other oily foods to avoid soiling their hands. This is a bad habit. Because once the fluorescent whitening agent is eaten into the stomach, the effect on the body is definitely greater than direct contact with the skin.
source:
China office supplies network
Club Furniture,Club Dining Chairs,Modern Club Furniture,Club Lounge Furniture
Foshan Livemate Appliance Co., Ltd. , https://www.livemate-furniture.com