6 more Key Knowledge about Skin Care Sunscreen- How to apply sunscreen
6. When should I apply Sunscreen ?
Applying sunscreen just before going out is not effective in protecting your skin from the sun’s sunburn. Please apply at least 15 to 30 minutes before going out.
In case of some type of sunscreen, the UV protection effect is increased only when it is sufficiently absorbed into the skin.
If you go out for a long time, apply it once every 90 min ~ 120 minutes.
7. Two type of Sunscreen :
Chemical Sunscreens VS. Physical Sunscreens
Depending on the mode of action, sunscreens can be classified into physical sunscreens (i.e., zinc oxide and titanium dioxide, which stay on the surface of the skin and mainly deflect the UV light) or chemical sunscreens (i.e., UV organic filters, which absorb the UV light).
Physical sunscreen puts a thin reflective layer on the skin that bounces off ultraviolet rays. This is suitable for sensitive skin because it has less chemical ingredients than chemical sunscreens.
Physical sunscreens are recommended for acne skin.
Pros of Physical Sunscreens
- Offers protection from both UVA and UVB rays
- Protects from the sun as soon as it’s applied, no wait needed
- Lasts longer when in direct UV light (but not when doing physical activities that cause the skin to get wet or sweat)
- Less likely to cause a stinging irritation on the skin, making it better for sensitive skin
- Better for those with heat-activated skin(such as rosacea and redness) since it deflects the heat and energy given off by the sun away from the skin
- Less likely to be pore-clogging, making it ideal for acne-prone skin
- Longer shelf life
- Have little irritation to the eyes
Cons of Physical Sunscreens
- Can rub off, sweat off and rinse off easily, meaning more frequent re-application when outdoors as needed
- May leave a white-ish cast on the skin, making some formulas incompatible for medium to dark skin tones
- Can be less protective if not applied and re-applied generously and accurately since UV light can get between the sunscreen molecules and get into the skin
- There is tight feeling when applying
Chemical sunscreens are sunscreens that absorb UV rays. This is a method to block ultraviolet rays by converting ultraviolet rays into heat to make them disappear naturally
Pros of Chemical Sunscreens
- Less is needed to protect the skin because there is no risk of spaces between the sunscreen molecules after application
- Tends to be thinner and therefore, spreads more easily on the skin
- There is no white cast
Cons of Chemical Sunscreens
- Can possibly cause and increase in existing brown spots and discoloration due to a higher internal skin temperature ( over-heated skin can make brown spots worse, such as melasma)
- Requires about 20 minutes after application before it starts to work
- Increased chance of irritation and stinging (especially for those who have dry skin with a damaged moisture barrier) due to the multiple ingredients combined in order to achieve broad spectrum UVA and UVB protection
- The higher the SPF (such as formulas of SPF 50 or greater), the higher the risk of irritation for sensitive skin types
- The protection it offers gets used up more quickly when in direct UV light, so re-application must be more frequent
- Increased chance of redness for rosacea-prone skin types because it changes UV rays into heat which can exacerbate flushing
- May clog pores for oily skin types
- You must cleanse the chemical sunscreens well.
8. How much do I have to apply ?
Sunscreen cannot be expected to be effective without applying the required amount.
If you apply the sunscreen slightly, you can expect only the effect of SPF2. That is, you can hardly expect the effect of sunscreen.
The recommended dosage for sunscreen is a sufficient amount on both nodes of the second finger. Or it is enough to go up on a Korean 500 won coin
9. How often should I apply sunscreen?
During outdoor activities, SPF 60~50 sunscreen should be applied every two hours.
If you are spending the day outdoors, sweating, or are in the water applying just once in the morning is simply not enough in order to be fully protected and not get sunburned.
That’s why we say it’s a good idea to apply every 1 1/2 to 2 hours. It’s better to apply it more often when you sweat a lot or play in the water.
Make sure you pay attention more to cleansing when you put on sunscreen. Because Sunscreen could be tangled with waste matter or clogged pores while sleeping, causing skin trouble. And sunscreen with oiliness may break the oil and moisture balance of the skin
10. Not just for skin. Lips need UV protection, too.
Let’s pay attention to the UV protection of our lips.
In many cases, lips do not block UV rays through sunscreen Lips with thin skin are particularly vulnerable to UV protection.
When exposed to UV light for a long time, there is no melanin pigment, so the lips may become dull and wrinkles increase.
Therefore, apply lipstick or lip balm that protects against UV rays.
11. What is the shelf life of sunscreen ?
If you use a sunscreen that has passed the expiration date or is in poor storage condition, skin problems may occur
On the packaging, it says 6M, 12M, which means to use it for 6 months/12 months from the date of opening.
These days, the expiration date is written on the bottom of the container. Make sure that the expiration date is sufficient and use it within a year after opening the lid.
Be sure to check the expiration date before buy or use.