Types of sunscreen products
What is PA value? General consumers tend to ignore the damage of UVA, but UVA is the most likely to cause permanent damage to the skin. The PA value represents the ability of sunscreen to protect against UVA. The PA value is the UVA prevention effect measurement standard published by the Japan Cosmetics Federation. It can be divided into three levels: PA+, PA++, and PA+++. The more + numbers, the higher the protection index. Is the higher the SPF coefficient and PA value, the better? Dermatologists point out that generally if there are no special needs, such as long-term exposure to the sun or outdoors, using SPF15 and PA++ products can meet our needs for protection, so there is no need to blindly pursue high-factor sun protection. products, increasing the burden on the skin. The U.S. label for UVA protection is PPD, while PFA is the French label.
What is SPF?
Sun Protection Factor=SPF, the abbreviation of sun protection factor. SPF is the U.S. Food and Drug Administration (FDA) standard factor for UVB protection of sunscreen products. The higher the SPF, the longer the skin can resist sunburn. Approximately long. It is an indicator of sun protection function, which is the time that the skin can resist UVB under the protection of sunscreen and avoid redness and sunburn. For example, if a person who gets red after being exposed to the sun for 2 minutes uses sunscreen lotion SPF20, the time it takes to protect his skin from getting red can be extended 20 times, that is, 40 minutes.
Types of sunscreen products:
Generally, sunscreen products can be divided into physical, chemical, and mixed types.
Physical sunscreen prevents ultraviolet rays by refraction. The advantage is that it is gentle and non-irritating, but the disadvantage is that it is drying. The matrix in sunscreen is used to form a layer of reflective film to directly block or reflect and scatter away ultraviolet rays.
The two most commonly used ingredients are zinc oxide and titanium dioxide.
- Advantages: Stable at high temperatures and non-irritating, and will not cause allergies.
- Disadvantages: With high oil content, the molecules will turn white. prone to acne
Chemical sun protection
Chemical sun protection works by absorbing ultraviolet rays and converting them into substances that do not harm the skin. The advantage is that it has high ductility and strong coverage, but the disadvantage is that it may be more irritating and even cause allergies or acne. The physical and chemical hybrid type is a newer sunscreen. It is not only suitable for normal skin types but also has full effects on UVA, UVB, IR, etc. It can also reduce pigmentation, delay skin aging, and reduce skin cancer. probability of occurrence.