SPF test of sun umbrellas

The black sun umbrella has the highest sun protection index, and the silver plastic umbrella is followed by the umbrella posture.

Experts test on the instrument


Demonstrate parachute pose

Under the scorching sun, the umbrella is a must-have item for Ms. Aimei. It can not only be concave in shape, but also protect from the sun. But is this street full of colorful umbrellas really sun-proof? Which umbrella has the highest sun-protection index? Is it scientific to use a hundred yuan to discern whether it is not sun-proof? On August 13, a reporter from Chutian Metropolis Daily did it in an open place After a small experiment, on the 14th day of the next day, I came to the National Textile and Apparel Product Quality Supervision and Inspection Center for verification with the results of the experiment.


At 1:00 a.m. on August 13th, it was a period of intense sunlight. The reporter from Chutian Metropolis Daily placed three umbrellas on the market under the sun. Umbrellas are ordinary umbrellas with no sunscreen material (price of 20 yuan), silver plastic coated sunscreen umbrella (price of 60 yuan) and black plastic sunscreen umbrella (price of 100 yuan).

The reporters stood under the umbrella and felt that the vinyl umbrella was completely opaque, and the umbrella was shaded. The second is the silver plastic umbrella, which still has a faint light transmission. The worst is the ordinary umbrella. After not standing for a while, the skin has a burning feeling. And according to the netizen's trick: holding 100 yuan, if you can't see the watermark under the umbrella, you can protect against ultraviolet rays, and if you can see the watermark clearly, you can't protect against ultraviolet rays. The reporter operated in the same way and found that the watermark was particularly clear under the ordinary umbrella, and the silver glue and the black glue were completely invisible.

Expert testing

Black plastic umbrella is better than silver plastic umbrella

What's the truth? At 9 o'clock on August 14, the reporter brought the experimental results to the National Textile and Apparel Product Quality Supervision and Inspection Center (Hubei) for verification.

An engineer Tang Jinbo told reporters with a smile, "The 100 yuan note test can only be regarded as a little experience in life, and there is no scientific basis. The main reference values of sunscreen umbrellas are UPF (ultraviolet protection coefficient value) and UVA value (long wave ultraviolet). "

Put the three umbrellas for the reporter's experiment in an environment with a temperature of 20 ± 2 ℃ and a humidity of 65 ± 2%, and adjust the humidity for 8 hours. Then cut four samples of 50mm × 50mm size from the umbrella, and test the four samples successively with the instrument, and the average of UPF and UVA transmittance was taken as the result. In the end, the UPF of the ordinary umbrella is 13.71, and the UVA is 17.62%; the UPF of the silver plastic umbrella is 305.15, and the UVA is 1.85%;

According to Zhang Hongyan, director of the National Textile and Apparel Product Quality Supervision and Inspection Center, according to the National "Evaluation of the UV Protection of Textiles" regulations, the sun umbrella is only available when the UPF value of the umbrella fabric is greater than 30 and the UVA transmission rate is less than 5% It can be called "UV protection product". And the greater the UPF value, the smaller the UVA transmittance, the better the UV protection performance.

Then the black plastic umbrella wins, with the highest sun protection index, followed by the silver plastic umbrella.

■ Tips

Umbrella posture is exquisite

Engineer Tang Jinbo suggested:

1. In the case of a sunscreen coating, the darker the sunscreen umbrella, the better its anti-ultraviolet performance. In order to achieve a good sunscreen effect, it is best to love those elegant umbrellas.

2. Sunscreen umbrellas are best not used as umbrellas. Rainwater has a corrosive effect on the sunscreen coating of the umbrella and affects the sunscreen performance of the umbrella.

3. Two upright and shoulder-carrying umbrella positions are people's usual way of playing umbrellas, but the sun-protection effect of shoulder-carrying is weaker than that of upright. Because when people take the position of holding the umbrella upright, the umbrella covers a wider range. In addition to blocking the direct sunlight, the surrounding environment reflects less light to the face.