Do you know all this knowledge about sunscreen clothing

Principles of Sunscreen Clothing

According to optical principles, transmittance+reflectance+absorption=100%. Therefore, the higher the reflectance and absorption of ultraviolet rays, the lower the transmittance, and the better the sun protection effect.

principle

The sun protection principle of sun protection clothing is to apply UV protection treatment to the fabric, which involves adding UV absorbers or UV reflectors in various ways to improve the reflection and absorption ability of the sun protection clothing to prevent UV rays from passing through the clothing and damaging the skin.

UV absorber

UV absorbers, through selective absorption of UVA and UVB, and energy conversion, achieve the role of UV shielding. In actual production, benzophenones and Benzotriazole are the most commonly used, with high melting point, low toxicity, poor heat resistance, high temperature decomposability, and certain irritation to the skin.

UV reflector

UV reflectors achieve UV protection by reflecting and refracting external ultraviolet rays. They have high effectiveness, good safety performance, and long-lasting effects. In practical production, metal oxide particles or ceramic powders are most commonly used, such as talc powder, calcium carbonate, zinc oxide, titanium dioxide, etc.

Relevant standards and main indicator requirements

In China's standard system, the main standard for sun protection products is GB/T 18830-2009 "Evaluation of UV Protection Performance of Textiles".

According to the requirements of this standard, when the UPF of the sample is greater than 40 and T (UVA) AV is less than 5%, it can be referred to as a "UV resistant product".

Focus on two indicators

CAUTION

#UPF

UPF, also known as UV protection factor, refers to the ratio of the average effect of UV radiation calculated when the skin is unprotected to the average effect of UV radiation calculated when the skin is protected by fabric.

#T (UVA) AV

T (UVA) AV refers to the transmittance of sunlight ultraviolet radiation with wavelengths ranging from 315 to 400nm.

The higher the UPF and the lower the UVA, the better the UV protection effect of the fabric.

Common sunscreen clothing fabrics

01

Knitting

Knitted sunscreen clothing fabrics are mainly made of cotton or polyester cotton blends, which have good breathability and comfort, strong moisture absorption, but poor UV resistance.

02

Woven

The woven fabrics for sun protection clothing are nylon, polyester, etc., which are most commonly used in the sun protection clothing market. Nylon dominates in terms of wear resistance and moisture absorption, while polyester has great advantages in comfort functions such as breathability and contact cooling.

The influence of fabrics on sun protection performance

1. The thickness and porosity of the fabric

The thicker the thickness and the tighter the structure, the smaller the corresponding porosity, and the better the UV protection effect of the fabric.

But for sunscreen clothing fabrics, the first thing to ensure is that they are both light and thin, and dense and porous fabrics can be considered.

2. Color of fabric

Color is also an important factor affecting the UV resistance of fabrics. After dyeing, fabrics contain some dye molecules, and the groups on the dye molecules enhance their absorption of UV rays.

The higher the purity, the better the ability to absorb ultraviolet rays, so it is preferable to choose sun protection clothing with relatively dark colors.

Comfort requirements for sun protection clothing

Breathability

Refers to the performance of gas passing through the fabric, which directly affects the thermal and wet comfort of sunscreen clothing.

Sunscreen clothing is required to have good breathability when worn in summer, in order to quickly dissipate heat and avoid making people feel stuffy.

Moisture permeability

The performance of gaseous moisture passing through the fabric is an important indicator for evaluating the comfort of sunscreen clothing.

In scorching summer days, the human body produces a certain amount of heat and sweats. It is required that sun protection clothing has good moisture permeability to avoid people feeling stuffy and sticky when wearing it.

The breathability and moisture permeability of sunscreen clothing are influenced by various factors such as density, porosity, thickness, and finishing method.

Some sunscreen clothes do not live up to their name

Poor UV protection effect

The UV protection treatment process and fabric structure of sunscreen clothing are unreasonable, which cannot meet the standard requirements. The UV protection coefficient UPF value is lower than 40 or the UVA transmittance T (UVA) AV is greater than 5%. Wearing it under scorching sun for a long time, it does not have the sun protection effect and can easily cause skin sunburn and even other skin diseases.

Fiber composition or content does not match the label

The actual fiber content of sunscreen clothing does not match the fiber content labeled on the product. False or incorrect labeling of fiber components can easily mislead consumers. Poor fiber materials can easily cause non sweat absorption, breathability, and trigger skin itching.

Label description is not standardized

The label description is not standardized, mainly including: not indicating the UV protection performance standard; Unmarked UV protection performance indicators, such as UPF value; Incomplete labeling of the name and address of the country of origin, agent, importer, or seller.

Labels are an important source of information for consumers when choosing products, and also an important basis for consumers to protect their rights.

Selection and purchase of sunscreen clothing

Take a look at the label

According to GB/T 18830-2009, the label of sunscreen clothing must include three aspects:

In addition, when importing sunscreen clothing, attention should be paid to whether there is product information labeled in Chinese on the product and its packaging: product name, product model or specification, fiber composition and content, maintenance method, safety category, origin, name and address of the agent, importer or seller, etc;

At the same time, keep your eyes open and pay attention to whether the information marked on the outer packaging, hanging tags (certificate of conformity), and durability labels are consistent.

Secondly, selecting fabrics

Nylon and polyester fabrics are the most commonly used in the market; The preferred fabric is soft and elastic, with light weight, soft feel, simple cleaning, and easy and comfortable wearing; Choose fabrics with fine and solid texture, which have less light transmission and better sun protection effect; Avoid purchasing sun protection clothing treated with coating method, as it has poor breathability, is uncomfortable, and the coating is prone to peeling off after washing, resulting in a decrease in sun protection ability.

The third is to choose colors

Dark colored sun protection clothing has better performance in reflecting ultraviolet rays than light colored sun protection clothing. Therefore, when choosing sun protection clothing, it is recommended to choose dark colored sun protection clothing, while black and red series sun protection clothing have relatively better effects.

Fourth, choose a style

There are various styles of sun protection clothing, and you can choose a high collar three-dimensional cut for a better fit, stronger protection, and more convenient activity; The widened brim design can also improve the sun protection effect on the face. In addition, in order to improve the breathability and sweat-wicking performance of sunscreen clothing, you can choose styles with small holes in the armpits and back