Experimental equipment: beaker, boiled water, n-hexane, scissors, UV, paper tube compression tester

Experiment 1 decolorization experiment

The main purpose of decolorization experiment is to test whether the outer wall pattern of advertising paper cup is decolorized after soaking in water and n-hexane for 30 minutes (according to the national standard, it is soaked in water and n-hexane respectively). If there is decolorization phenomenon, it means that the experimental product is unqualified.

The experimental steps were as follows

1. Take one cup from each of the four kinds of paper cups, cut off the parts with patterns on the cup body with scissors, and put them into four beakers after cutting. Press this to prepare two groups.

2. Pour boiling water at 90 ℃ into 4 beakers of the first group and soak for 30 minutes.

3. Inject 150 ml n-hexane into 4 beakers of the second group and soak for 30 minutes.

The results were as follows

After soaking in boiling water and n-hexane at 90 ℃ for 30 minutes, no obvious decolorization was observed in the four kinds of paper cup samples with patterns.

Experts explained:

According to mohao, the ink quality and processing technology are qualified, and the pattern printed on the disposable paper cup will not be soluble in water or n-hexane. If the decolorization phenomenon appears in the experiment, it indicates that the ink and processing technology are unqualified. Long term use of this paper cup will cause harm to human health.

Experiment 2 fluorescence detection experiment

If the paper used for the paper cup contains fluorescent agent, fluorescent spots will appear on the paper cup under the light of three ultraviolet meters. According to the relevant regulations on the quality supervision and inspection of paper cups issued by the state last year, the maximum fluorescent area of 100 square centimeter disposable advertising paper cups shall not be greater than 5 square centimeters. If the test result is higher than this data, the product is unqualified.

The experimental steps were as follows

1. Cut out about 100 square centimeters of four kinds of paper cups and unfold them.

2. Put them under the three ultraviolet instruments to observe whether there are fluorescent spots on the outer wall and inner wall of the cup.

The results were as follows

There were no fluorescent spots on the inner walls of No.1 and No.2 paper cups, and different numbers of fluorescent spots appeared on the inner walls of No.3 and No.4 paper cups, but the areas were not more than 5 square centimeters.

Experts explained:

According to mohao, some paper cup manufacturers will bleach the paper used for paper cups with fluorescent agents in order to make the appearance of advertising cups look beautiful. However, excessive intake of fluorescent agents is harmful to human body. In order to regulate this behavior, the use of fluorescent agent in the manufacturing process of disposable paper cup is regulated by the state. After inspection, the fluorescent area of four kinds of paper cup paper with the size of about 100 square centimeter used in this experiment does not exceed 5 square centimeter, so it is a qualified product.

Experiment 3 paper cup compression test

Whether the advertising cup is soft or deformed after being placed in hot water or water for a long time depends on the paper stiffness of the cup itself, and the greater the stiffness, the less likely it is to deform. The paper tube compression tester tests whether the paper cup is qualified by extruding the cup and testing the pressure that the cup can bear.

The experimental steps were as follows

Four kinds of disposable paper cups were put into the paper tube compression tester to test, read and record the experimental results.

The results were as follows

The compression coefficient of No.1 and No.3 paper cup is 260 n, that of No.2 paper cup is 218 n, and that of No.4 paper cup is 144 n. In the compression test, the paper cup with 3 yuan per package (36 cups) has the worst compression resistance, that is to say, its cup wallpaper is soft and easy to deform in the process of use.

The quality of the experimental summary is proportional to the price

Four kinds of disposable paper cups with different prices and specifications were randomly purchased in supermarkets and convenience stores in urban areas. After decolorization, fluorescence and compression tests, the data all met the national standards.

According to the overall inspection of disposable paper cups sold in the city in the past, the qualified rate of the main indicators is still relatively high, and the public can basically use them at ease. However, from their test results, quality and price are in direct proportion.

Remind to identify disposable paper cup can "look, press and smell"

Buy disposable paper cups, to regular supermarkets, stores, check the product's QS logo, production date, etc., do not covet small cheap. From the printing pattern of the cup body, the outline of the pattern should be clear and the color should be uniform. There should be no printed matter within 15mm from the cup mouth to the cup body and 10mm from the cup bottom to the cup body. If it is beyond this regulation, the cup is unqualified.

How to identify disposable paper cups? Citizens can do this by "watching, pressing and smelling". Let's see: the label information on the package is incomplete, whether the production license number and QS mark are marked; the color of the paper cup should not be too bright; the cup body should not have black spots and white bright spots, and the overall color should be uniform. Look at the paper cup at the light, there must be no impurities. Two pressure: you can use your hand to squeeze the two sides of the paper cup to roughly know the quality of the cup. If the paper cup is hard and thick, the quality is better; the thinner and lighter the paper cup, the worse the quality. Third smell: smell the paper cup for pungent odor, especially for the smell of ink or mildew.