Isooctyl 00 methoxycinnamate (commonly known as OMC) is the most widely used ultraviolet absorber in sunscreen cosmetics. Its ultraviolet absorption wavelength is 290-320 nm. The general dosage is between 3% and 7.5%, and it is often used in combination with UVA ultraviolet absorber (β-diketone compound tert-butyl methoxydibenzoylmethane (commonly known as 1789), which is the most representative and efficient UVA ultraviolet absorber. ) to achieve broad-spectrum or full-effect sunscreen effect. In the pure compound state, OMC has high photostability. However, in the emulsion system of sunscreen cosmetics, especially in the presence of water and surfactant, its light resistance or light resistance under ultraviolet rays is not too high, and 10 MED (minimum erythema dose, that is, the minimum radiation dose required for human skin to produce erythema within a certain period of time after being irradiated by sunlight) is usually needed. Usually used to determine SPF value), about half of the effective components are degraded by light. This is why it is usually necessary to add a higher dose to the formula to play an effective role. The photodegradation products of OMC can irritate the skin to some extent. In order to reduce the irritation of users with sensitive skin after applying sunscreen cosmetics, it is usually necessary to add anti-inflammatory ingredients such as bisabolol, aloe and dextran to minimize the irritation of the products. 4- methylbenzylidene camphor is a UVB ultraviolet absorber with high photostability and high absorption efficiency, and it has a certain stabilizing effect on UVB ultraviolet absorbers such as OMC and benzophenone -3. Its ultraviolet absorption wavelength is 290-320 nm. The dosage is generally between 0.5% and 4%, and it is often used in combination with UVA ultraviolet absorber (such as 1789) to achieve broad-spectrum or full-effect sunscreen effect, and at the same time play a role in protecting and stabilizing 1789.
When choosing sunscreen, don't just look at the SPF value and PA value on its surface, and don't just rely on the feeling of the skin to say whether it is refreshing, mild and non-irritating. An ideal sunscreen should be able to protect UVA and UVB at the same time, and the effective components contained will not decompose in the sun, and the effective components and ineffective components are safe for adults and children. The evaluation of effective components of sunscreen mainly includes three aspects: anti-ultraviolet ability, stability and health hazards.
Theoretically, compounds that can absorb ultraviolet rays can be used as ultraviolet absorbers as long as they have sufficient safety and good solubility. However, it is a complicated and long-term process to evaluate the safety of ultraviolet absorbers. All countries strictly control the use of ultraviolet absorbers. For example, in the United States, ultraviolet absorbers are managed as OTC drugs. Although major companies have developed many ultraviolet absorbers with various structures, the types of ultraviolet absorbers approved for use are limited. At present, there are 17 kinds of sunscreen approved by FDA in the United States, 29 kinds approved by EU and 28 kinds approved by China. Here is a brief introduction to some mainstream sunscreens (green ones are allowed in China).
00 1. Octyloxy (octyl methoxycinnamate) octyl methoxycinnamate
This is the most widely used UVB sunscreen (all UVB sunscreens are not specifically pointed out later), and it has little irritation to the skin, but it has been observed in animal experiments that it has an effect on estrogen.
002. Hydroxybenzophenone -3
00 is related to photosensitive reaction, which will be absorbed through the skin. This substance was found in 86 urine samples of 90 girls aged 6 to 8.
003. octyl salicylate
This is a weak UVB absorbent, but it is safer and will increase the skin's absorption of other components.
004.titania
00 is hardly absorbed by the skin, and there is no report that it is harmful to health. More than 70% sunscreen was used.
005. Avobenzone 4- tert-butyl -4'- methoxydibenzoyl methane
00 is the main UVA absorption component. However, sunlight can decompose this substance into unknown compounds, especially in the presence of other active ingredients, octyl ester.
006. zinc oxide zinc oxide
Zinc oxide has a long history in skin care products and is widely used. At present, there are no reports of health hazards. More than 30% sunscreen was used.
007. Propylene (2- cyano-3,3-diphenyl-2- ethylhexyl acrylate)
00 is usually used in combination with other ultraviolet absorbers to achieve a higher SPF value, but this substance will release oxygen free radicals when exposed to ultraviolet rays.
008. Humulus salicylate (isooctyl methoxycinnamate)
This is an ultraviolet absorber. However, studies show that weak hormone action will produce toxic metabolites and enhance the absorption of some toxic herbicides.
009. benzimidazole sulfonic acid
A UVB absorbent, when exposed to sunlight, will produce free radicals, which will cause DNA damage and possibly cause cancer.
00 10. menthyl lactate
00 mild UVA absorbent is not allowed to be used in the EU and Japan. A study found that harmful oxygen free radicals are produced in sunlight.
0. micronized zinc oxide and titanium dioxide micronized zinc oxide and titanium dioxide.
00 nm zinc oxide
00 zinc oxide and titanium dioxide can provide more protection after the particle size becomes smaller, but whether to use micronized particles, especially nanoparticles in cosmetics, is still controversial, but some studies believe that micronized particles will produce certain toxicity.
00 12. o (octyl dimethyl PABA) p-aminobenzoic acid phthalate
This is a derivative of PABA, a widely used sunscreen. Studies have shown that this substance can release free radicals, damage DNA, have estrogen activity, and have a sensitive effect on some people.
00 13.Tinosorb s (bis-dihexyloxyphenyl triazine) bis-ethylmethylphenol methylaminobenzoxazine.
This sunscreen has passed the FDA and EU certification. Tinosorb S is a registered trade name of ciba company. This is an oil-soluble substance and a broad-spectrum UVA and UVB absorbent. The research on this substance is not enough, only that it has light stability and no estrogen activity.
00 14. Sulfophenone (benzophenone -4)
This substance is irritating to the skin and eyes and is not absorbed by the skin, but it will enhance the absorption of other chemicals.
00 15. methoxy SX (p-xylylenedicamphorsulfonic acid) p-phenylene dimethylenediaminocamphorsulfonic acid (methoxy SX is a trade name, the same below).
This is a sunscreen for UVA just approved by FDA in 2006. Skin absorption is low, but 2 hours of sunlight can decompose 40% of substances.
00 16. triazole trisiloxane cresol triazole trioxane
00 FDA not approved. It can provide UVB and partial UVA protection, and it is not carcinogenic, but it may have an impact on the water environment.
00 17.4- methylbenzylidene camphor 4- methylbenzylidene camphor
00a UV filter, not approved by FDA. Australia and Japan are allowed to use. Studies in Europe believe that this substance is toxic to the thyroid gland and interferes with hormones, so it is not recommended to use it in sunscreen. However, there are still products that use it as an active ingredient, and this sunscreen is approved for use in China.
00 18. paso SLX (polysiloxane-15)
00 A UVA absorbent, not approved by FDA, but approved by Australia and Japan.
00 19. ethylhexyl methoxycinnamate
00 is a UVB absorbent, but it has not been widely used.
0020. amyl dimethyl PABA PABA ethyl amyl ester
00 US FDA has not approved it (it is not specifically pointed out below that all FDA are approving it), and it is found in animal experiments that it is irritating to the skin at moderate concentration. Both Canada and Japan have restricted the use of this sunscreen, but the European Union has approved its use.
002 1.PEG-25 PABA
00 Australia and Japan approved the use, there will be skin absorption.
0022. Polyacrylamide ethyl benzylidene camphor polyacrylamide methyl benzylidene camphor
00 Australia approved for use.
0023. Methylene bis-dihexylxylene triazine Methylene bis-benzotriazolyl tetramethylbutylphenol
00 FDA is in the process of approval, and Australia and Japan are allowed to use it. A broad-spectrum UVA and UVB absorbent with good photostability is not absorbed by skin. But it will have a long-term adverse impact on the water environment,
0024. Isopropyl methoxycinnamate Isoamyl methoxycinnamate
00 EU approved the use, but Japan banned the use of this chemical containing certain components.
0025. Isoamyl trimethoxycinnamate trisiloxane
00 EU approved for use.
0026. Aminoxime acid (isoamyl p-methoxycinnamate) isoamyl p-methoxycinnamate.
00 UVA absorbent approved by US Food and Drug Administration is allowed to be used in EU, Australia and Japan. Animal experiments show that high dose may have an effect on reproductive system, but low dose has not been observed.
0027. glycerol PABA PABA glycerol hexyl ester
00 EU approved for use, moderate concentration is irritating to the skin.
Ferulic acid Ferulic acid
00 EU allowed to use. Medicine is used to treat coronary heart disease and cerebrovascular disease, and cosmetics mainly use its anti-ultraviolet and anti-oxidation functions, but animal experiments have found that high concentration can induce tumor growth.
0029.u vinul t 150 (ethylhexyl triazinone) ethylhexyl triazinone.
00 UVA absorbent approved by US Food and Drug Administration is allowed to be used in EU, Australia and Japan. Research shows that it will have a long-term impact on the water environment.
0030. Disodium salt of neohelio panap (dioxin phenyl benzimidazole tetrasulfonate) 2,2'-bis -( 1, 4- phenylene) benzimidazole-4,6-disulfonic acid.
00 A UVA absorbent is allowed to be used in Australia.
003 1.uvas orbheb (diethoxybutyryl amino triazinone) diethylhexylbutyryl amino triazinone
00 a UVA absorbent. The FDA of the United States is in the process of approval, and the European Union, Australia and Japan are all allowed to use it. At present, it is only found that the substance is non-toxic and carcinogenic, and its safety can not be completely determined.
0032.U Vinul A Plus (diethylamino hydroxyl benzoyl benzoate) diethylamino benzoyl benzoate
00 A UVA absorbent is allowed to be used in Australia.
Camphor benzalkonium bromide methyl ester
00 Australia and Japan are allowed to use.
Benzylidene camphorsulfonic acid
00 Australia and Japan are allowed to use.
0035. benzophenone -9
These benzophenone compounds are allowed to be used in the European Union, and there is clear evidence that these compounds are toxic to human skin.
0036.benzophenone -6
There is clear evidence that this compound is toxic to human skin. In animal experiments, low concentration has an effect on sensory organs, and in vitro experiments will lead to DNA mutation in non-mammalian cells.
0037. benzophenone -5
There is clear evidence that this compound is toxic and irritating to human skin.
0038. benzophenone -2
There is clear evidence that this compound is toxic to human skin. In animal experiments, low concentration has an effect on sensory organs, in vitro experiments will lead to DNA mutation in mammalian cells, and high concentration will interfere with endocrine system.
0039. benzophenone-1
There is clear evidence that this compound is toxic to human skin. The results of animal experiments show that moderate concentration interferes with endocrine system, low concentration affects the whole system, and high concentration affects brain and nervous system.
0040. Benzocaine ethyl p-aminobenzoate
00 EU allowed to use. However, studies have shown that moderate concentrations are irritating to the skin, and high concentrations have been found to have effects on the brain and nervous system in animal experiments, so the Canadian government has restricted the use of chemicals to be unsafe.
00 camphor derivatives (such as methyl benzyl camphor, commonly known as MBC) can stabilize UVB ultraviolet absorbers such as OMC and benzophenone -3 to some extent, and have high light stability and high absorption efficiency as UVB ultraviolet absorbers.
Benzophenone, such as benzophenone -3 and benzophenone -4, is a broad-spectrum ultraviolet absorber, but its absorption performance is worse than the above three, and its sunscreen effect is not ideal. Its ultraviolet absorption wavelength is 250-350 nm. The addition amount is generally between 0.5% and 6%. Used in the formula, it mainly plays the role of preventing the product from changing color easily after being irradiated by sunlight or ultraviolet rays.
Among many organic ultraviolet absorbers with high light resistance, many triazine and benzotriazole ultraviolet absorbers have been proved to be two kinds of compounds with high safety and light resistance. At present, the representative ones on the market are "ethylhexyl triazinone" or "octyl triazinone", such as Uvinul T 150 produced by BASF Company, whose ultraviolet absorption wavelength is 280-320nm. The addition amount is generally between 0.5% and 5%. If the appropriate polar oil can be selected, a higher sunscreen effect can be achieved at a lower dosage. Because it is skin-friendly and not absorbed by the skin, it is more suitable for making waterproof and sunscreen products.
00 tert-butyl methoxydibenzoylmethane (Avobenzone, commonly known as 1789) is the most representative and efficient UVA absorbent. Its ultraviolet absorption wavelength is 320-400 nm. The dosage is generally between 1~3%, and it is often used in combination with UVB ultraviolet absorber (such as OMC or MBC) to achieve broad-spectrum or full-effect sunscreen effect. Because of its molecular structure, it has a congenital deficiency of poor light stability, but by combining it with an appropriate UVB ultraviolet absorber with high light stability (such as 4- methylbenzylidene camphor), it can give full play to its high efficiency in protecting long-wavelength ultraviolet rays. UVA absorber is the only long-wavelength ultraviolet absorber approved by FDA at present, and its safety in sunscreen cosmetics has passed the long-term strict evaluation and review by FDA. Avoid contact with heavy metals, iron ions and preservatives that will release formaldehyde during production and use.
00 p-phenylene dimethylene biscamphor disulfonic acid and salt ultraviolet absorber are water-soluble UVA ultraviolet absorbers (such as methoxy SX), which have strong absorption in the whole UVA region (320-380nm) and part of UVB region, and the absorption range is wider than that of ordinary UVA absorbers. It has high light stability and water solubility, and can be used conveniently with various UVB ultraviolet absorbers in the formula to obtain a broad-spectrum sunscreen effect, which is more suitable for spray-type or water-soluble sunscreen products. In the past, only L 'Oré al was used because of the limitation of L 'Oré al's patent. At present, domestic manufacturers are promoting this product.
The common inorganic ultraviolet absorbers are: In view of the shortcomings of low light stability or poor light resistance of organic sunscreens, people turn their attention to inorganic compounds. Typical metal oxides are titanium dioxide and zinc oxide. As far as titanium dioxide is concerned, it is mainly used in the formulation of sunscreen cosmetics because of its scattering and reflection of short-wave ultraviolet UVB (290 ~ 700 nm) and its covering effect on skin. Titanium dioxide, which is commonly used in cosmetic formulations, mainly covers the skin because of its large particles (for example, the particle size is between 500 nm and 2000 nm), and its sunscreen or UVB ultraviolet scattering effect is poor. As a sunscreen, ultrafine titanium dioxide has the best scattering effect on UVB ultraviolet rays. When combined with organic ultraviolet absorber, it greatly improves the SPF value of the formula. As sunscreens, titanium dioxide and zinc oxide are often used in combination with organic sunscreens, and it is difficult to achieve high sunscreen effect and good use effect when used alone.
00 sunscreen product effect evaluation
00SPF value, that is, sun protection index or sun protection index, is expressed by the ratio of the minimum irradiation dose or the shortest time required for the erythema of protected skin to the minimum irradiation dose or the shortest time required for the erythema of unprotected skin according to the situation of erythema of skin irradiated by UVB. It represents the actual sunscreen effect of sunscreen cosmetics and is a quantitative index to measure sunscreen effect based on anthropometry.
In view of the fact that the definition of SPF value is based on human measurement, it has become an international standard mode to measure SPF value by human skin test technology (that is, "human body method"). The laws and regulations of major countries have established and stipulated the "human body method" standard method for determining and labeling the "SPF" value of sunscreen cosmetics. Evaluating the SPF value of sunscreen cosmetics by instrumental method can be used as a quick and effective tool for manufacturers to choose sunscreen, how to obtain the best combination of sunscreen and evaluate new sunscreen.
00SPF value is to evaluate the protective effect of UVB. With the enhancement of consumers' awareness of UVA protection and the importance of full-band ultraviolet protection, how to evaluate the protective effect of UVA is popular in the market at present, based on a standard formulated by Japan Cosmetics Industry Association. The evaluation standard of UVA has not been defined in China, and there is no unified test and expression standard of UVA protection effect of sunscreen cosmetics in the world.
At present, more and more manufacturers are interested in producing high-performance sunscreen products. In fact, SPF 10 sunscreen products can filter 85% UVB ultraviolet rays, SPF 15 sunscreen products can filter 95% UVB ultraviolet rays, and SPF30 sunscreen products can filter 97% UVB ultraviolet rays. Therefore, SPF 10~ 15 products can achieve better protection effect in daily situations.
Several aspects that should be paid attention to in developing 00 sunscreen products
The success of the development of sunscreen products depends on whether the general cream formula is removed, especially the stability of SPF value of the formula during the shelf life, the influence of the formula matrix on the product packaging and the influence of the formula matrix on the skin. Here we mainly recommend some general guidelines to keep the SPF value stable during the shelf life.
Selection of emulsifier in the formula of 00 sunscreen products
How to really achieve the effect of waterproof and sweat-proof sunscreen cream or emulsion, the choice of emulsifier is very important. Especially for O/W formula, you can choose Prolipid 14 1 produced by ISP or Amphisor series emulsifier produced by Roche. If a certain amount of film-forming agent can be added, the waterproof and sweat-resistant performance of the formula will be icing on the cake. W/O formula, because of its characteristics, can easily achieve waterproof and sweat-proof performance. At the same time, the particle size of emulsion will also affect SPF value. It follows a simple rule, that is, the smaller the droplet, the greater the SPF value. Usually, the use of high-speed dispersion homogenizer is beneficial to the good dispersion of internal phase of emulsion.
At present, the sunscreen spray formula is popular, and the emulsifier can be selected from related emulsifiers recommended by SEPPIC and SYMRISE.
00 the choice of sunscreen
Correct selection of ultraviolet absorber is the key for formulators. Even the ultraviolet absorbers of the same type of UVB part do not all have the same effect: some ultraviolet absorbers are obviously superior to others. Here, the absorption capacity of the ultraviolet absorber is related to the SPF value obtained, that is, the ultraviolet absorber with high absorption capacity contributes better to the SPF value. Such as ethylhexyl triazinone and methyl benzyl camphor, can provide relatively high SPF values at very low concentrations. At the same time, the combination of UVA and UVB ultraviolet absorber and the combination of inorganic sunscreen and UVB ultraviolet absorber are obviously helpful to improve SPF value. How to cooperate should be determined according to relevant experiments.
Selection of grease in 00 oil phase
Whether it is O/W or W/O emulsion system, the selection of other oils and fats except sunscreen should follow the principle of maximum mutual solubility with sunscreen or solubilization of sunscreen and easy complete emulsification. This can prevent the product from delamination during storage, which will lead to the decrease of sunscreen effect.
00 selection of additives
Especially in the formula with high SPF value, besides considering the synergistic effect of sunscreen, it is necessary to add some anti-allergic and anti-irritating active ingredients, such as allantoin, bisabolol and so on, to reduce the skin irritation caused by photodegradation of sunscreen due to light and other factors.
Other rheological properties, such as too thin formula to determine SPF value, will affect the sunscreen effect, and too thick and uneven application will also affect the determination of SPF value and the effective display of sunscreen effect. And the effects of different sunscreens on packaging, all need to carry out relevant experimental tests.