Sunscreen

Sunscreen refers to cosmetics that are added with a sunscreen that can block or absorb ultraviolet rays to prevent the skin from being tanned or sunburned. According to the principle of sunscreen, sunscreen can be divided into physical sunscreen and chemical sunscreen.

Sunscreens need to choose products with different SPF or PA values ​​according to specific objects to achieve the purpose of sun protection. The principle of sunscreen is to isolate the skin from ultraviolet rays. The main difference between sunscreen and sunscreen is the physical properties. The general water content of the cream is about 60%, which looks relatively 'thick' and creamy; while the water content of the lotion is more than 70%, which looks relatively thin. fluidity. Generally speaking, lotions are more refreshing than creams because of the higher water content, but formulators can still use different oily ingredients and thickeners to adjust the 'greasy' level of creams. Therefore, we still need to look at the product itself.

Sunscreen uses inorganic and organic active ingredients to act as sunscreen, mainly to prevent sunburn, photoaging, and sunburn.


Summary
Sunscreen can be divided into physical sunscreen and chemical sunscreen. However, chemical sunscreens have better skin feel and visual effects, and people with sensitive or extremely dry skin are more suitable for physical sunscreen.

Physical sunscreen
Sunscreen particles are used to form a protective layer on the surface of the skin to reflect the light waves that may be harmful to the skin in the ultraviolet rays to achieve the purpose of protecting the skin. Physical sunscreen particles generally stay on the surface of the skin and will not be absorbed by the skin, so the burden on the skin is relatively small, and it is not easy to cause skin sensitivity.

Chemical sunscreen
Through the combination of certain chemicals and cells, before the cells are damaged, the ultraviolet rays that may cause damage to the skin are absorbed to achieve the purpose of sun protection.


The tiny particles in physical sunscreens are generally composed of titanium dioxide and zinc oxide. As for chemical sunscreens, salicylate, cinnamate and anthranilate are considered safer and non-irritating sunscreen ingredients.


The effectiveness of sunscreens mainly depends on the SPF and PA values ​​of sunscreens. The higher the SPF index, the longer the UV protection time, but it does not mean that the higher the SPF value, the stronger the protection.


usage time
Ideally, sunscreen should be used after cleansing and before applying makeup to ensure that it fits tightly.

Skin cells to be protected. But in practice, basically after the daily skin care steps are over, you can apply sunscreen and then apply daily makeup. However, sunscreen, like general skin care products, takes a certain amount of time to be absorbed by the skin, so you should apply sunscreen 10-20 minutes before going out.

At the same time, it should be noted that the duration of the effect should be determined according to the SPF or PA value of the product.

Application area
Apply sunscreen to cover the neck, chest, arms, ears (parts that are particularly easy to be forgotten and sunburn), and any other exposed parts.


Use matters
1. Application area

When applying sunscreen, don't neglect the neck, chin, ears and other parts to avoid uneven skin tone.


2. Cleaning products

Be sure to completely remove sunscreen products every night, so do not take sunscreen to rest and sleep.

3. Use enough

Sunscreen is not effective when it is applied, but a certain amount can be effective. Usually, the amount of sunscreen applied on the skin is 2 mg per square centimeter to achieve the desired sun protection effect. It should be noted that the SPF value cannot be accumulated. Two layers of SPF10 sunscreen will only have the protective effect of one layer of SPF10.

4. Do not mix sunscreens of different brands

Mixed use will increase the possibility of skin irritation. The ingredients of sunscreens of various brands are inconsistent. If they are mixed and overlapped on the skin, it may cause the ingredients to interfere or repel each other, reduce the sun protection effect, and even cause skin allergies.

5. Pay attention to save

If exposed to heat or direct sunlight for a long time, the effect of sunscreen may be reduced. Do not use deteriorated sunscreen cosmetics, because it not only reduces the sunscreen effect, but also more likely to irritate the skin.

6, pay attention to sunscreen blind spots

When applying ordinary sunscreen, you also need to pay attention to the eye and lips skin. But if there is no instructions, or use sunscreen products for the eyes, do not use it on the skin around the eyes.


Purchase items
General population
1. Skin test

It is recommended to do an accurate skin test before buying sunscreen. Oily skin should choose water-based sunscreen products with strong penetration; dry skin should choose cream-like sunscreen products; medium skin generally has no strict regulations, and emulsion-like sunscreen is suitable for all kinds of skin.

2. Calculate the SPF value

Generally speaking, the higher the SPF index, the longer the protection period given.

3. Understand the applicable people of different sunscreens

Different sunscreen products have different applicable objects, the most
Combine Atlas
Combine Atlas

A good way is to try it on the inside of your wrist before buying. If the skin is red, swollen, painful, or itchy within 10 minutes, it means that you have an allergic reaction to the product. You can try a product with a sun protection factor that is one factor lower than this. If there is a reaction, it is best to give up the brand of sunscreen.

4. Skin quality testing

Due to the difference in oil secretion, skin texture will change, so a skin quality test should be done. Oily skin should choose foam cleansing products with strong cleansing power and water-based sunscreen products with strong penetration; dry skin should choose milky cleansing products and cream-like sunscreen products; neutral skin has a wider choice. Emulsion and spray sunscreens are basically suitable for all skin types.

Folding pregnant women and children
1. Reject whitening sunscreen products

Pay attention to the ingredients contained in sunscreens. Do not use sunscreens that also have whitening effects during pregnancy. Because some sunscreens with whitening functions add harmful metal elements, such as mercury, lead, arsenic, or use a large amount of finely ground titanium dioxide. The long-term absorption of mercury in the skin can cause nervous system disorders, vision loss, kidney damage, and hearing loss. Sensitive skin and mucous membranes can enter the embryo from the mother and affect the development of the embryo.

2. Avoid sunscreens with quick-acting skin rejuvenation effects

Studies have found that when a small amount of hormones are added to sunscreen products, the skin becomes plump and moisturized, but after a large amount of application, it will appear dry and spotting. Long-term use of hormone sunscreen products will damage the cells, and the skin will get closer and closer to aging, and hormones are not good for the fetus.

3. Don't touch the substances that cause skin allergies

Preservatives and pigments are substances that must not be 'stained' during pregnancy. At the same time, they are the three major substances that cause skin allergies. The more complex the fragrance ingredients, the greater the amount, the heavier the irritation, the more likely it is to cause skin allergies and photosensitivity reactions.

4. When buying sunscreen products, pay attention to the label on the package

The markings on the packaging include product name, manufacturer and address, hygiene license, production license, name of fulfillment standard, production date, shelf life or production batch number and restriction date, application instructions, etc. In addition, the logo of sunscreen products must also have a special purpose license number. When purchasing imported cosmetics, you must also check the import license number and the name and address of the distributor.

5. Physical sunscreen is preferred

6. Use test

Before use, be sure to test the skin reflection on the back of the ear. After half an hour, you can use it on a large area without allergy symptoms.


Sun protection misunderstanding
Can I not sunscreen on rainy days?

Whether it is cloudy or sunny, sun protection is required whenever you go out.

The higher the sun protection index, the better?

There are two standards for sun protection factor, one is SPF and the other is SPF.

The whole family can share sunscreen

You should choose a sunscreen that suits you according to your skin condition.

Pay attention to the food whitening red and black list

In some aspects of diet will also affect the sunscreen effect.