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The Formula rx Sun Relief Ceramide Silk Hydrating Sunscreen SPF 50 Versus Beauty of Joseon Daily Relief Sunscreen SPF 40

The Formula rx Sun Relief Ceramide Silk Hydrating Sunscreen SPF 50 Versus Beauty of Joseon Daily Relief Sunscreen SPF 40 This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50. This chemical sunscreen covers most of the UV range, light

The Formula rx Sun Relief Ceramide Silk Hydrating Sunscreen SPF 50 Versus Beauty of Joseon Daily Relief Sunscreen SPF 40

This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.

This chemical sunscreen covers most of the UV range, lighter on the deep UVA that drives aging.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Glycerin

Dicaprylyl Carbonate

Propanediol

Butylene Glycol

Diethylamino Hydroxybenzoyl Hexyl Benzoate

Titanium Dioxide

Ethylhexyl Triazone

Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine

Niacinamide

Glyceryl Stearate

Cetearyl Alcohol

Ceramide NP

Ceramide AP

Ceramide EOP

Phytosphingosine

Cholesterol

Nonapeptide-1

Linoleic Acid

Bisabolol

Sodium Hyaluronate

Panthenol

Allantoin

Sodium Lauroyl Lactylate

Xanthan Gum

Tocopheryl Acetate

Carbomer

Phenoxyethanol

Tocopherol

Disodium EDTA

Linolenic Acid

Ethylhexylglycerin

CI 77499

CI 77491

CI 77492

Water, Glycerin, Dicaprylyl Carbonate, Propanediol, Butylene Glycol, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Titanium Dioxide, Ethylhexyl Triazone, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Niacinamide, Glyceryl Stearate, Cetearyl Alcohol, Ceramide NP, Ceramide AP, Ceramide EOP, Phytosphingosine, Cholesterol, Nonapeptide-1, Linoleic Acid, Bisabolol, Sodium Hyaluronate, Panthenol, Allantoin, Sodium Lauroyl Lactylate, Xanthan Gum, Tocopheryl Acetate, Carbomer, Phenoxyethanol, Tocopherol, Disodium EDTA, Linolenic Acid, Ethylhexylglycerin, CI 77499, CI 77491, CI 77492

Homosalate

Butyloctyl Salicylate

Octocrylene

Ethylhexyl Salicylate

Dipropylene Glycol

Diethylhexyl 2,6-Naphthalate

Polymethylsilsesquioxane

Butyl Methoxydibenzoylmethane

Caprylyl Methicone

1,2-Hexanediol

Silica

Vp/Eicosene Copolymer

Pentylene Glycol

Behenyl Alcohol

Poly C10-30 Alkyl Acrylate

Polyglyceryl-3 Methylglucose Distearate

Inulin Lauryl Carbamate

Tromethamine

Acrylates/C10-30 Alkyl Acrylate Crosspolymer

Sodium Stearoyl Glutamate

Polyacrylate Crosspolymer-6

Oryza Sativa Extract

T-Butyl Alcohol

Water, Homosalate, Butyloctyl Salicylate, Octocrylene, Ethylhexyl Salicylate, Dipropylene Glycol, Diethylhexyl 2,6-Naphthalate, Polymethylsilsesquioxane, Butyl Methoxydibenzoylmethane, Glycerin, Caprylyl Methicone, 1,2-Hexanediol, Silica, Vp/Eicosene Copolymer, Pentylene Glycol, Behenyl Alcohol, Poly C10-30 Alkyl Acrylate, Polyglyceryl-3 Methylglucose Distearate, Cetearyl Alcohol, Glyceryl Stearate, Inulin Lauryl Carbamate, Tromethamine, Carbomer, Acrylates/C10-30 Alkyl Acrylate Crosspolymer, Sodium Stearoyl Glutamate, Ethylhexylglycerin, Polyacrylate Crosspolymer-6, Oryza Sativa Extract, T-Butyl Alcohol, Tocopherol

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Carbomer is a synthetic thickening and gelling agent. It's basically the ingredient that gives a lot of serums, gels, creams, and sunscreens their smooth, non-sticky texture.

Although legally permitted at very high levels, carbomers are normally used at concentrations below 1%.

It also needs to be neutralized to actually thicken, and because it is a large molecule, it doesn't really penetrate the skin barrier.

Allergy-wise, the risk is very low. Clinical studies show carbomers have low potential for skin irritation/sensitization even at concentrations up to 100%.

A 2024 UK study patch-tested 1,302 patients and found true allergy to the parent group of carbomer to be rare with no confirmed relevant reactions.

Cetearyl alcohol is a waxy mixture of two fatty alcohols: cetyl alcohol and stearyl alcohol. It is an emollient and emulsifier.

Despite having "alcohol" in its name, it has nothing to do with drying solvent alcohols; the FDA also allows "alcohol-free" products to contain fatty alcohols like this ingredient.

It plays several roles in a formula:

Typical use levels for this ingredient sit around 1-10% and the Cosmetic Ingredient Review Expert Panel has affirmed safety at concentrations up to 25% in leave-on products.

Multiple assessments have found it to be non-irritating and non-sensitizing to most people.

However, there have been some cases of allergic contact dermatitis in patients with chronically compromised skin barriers.

Cetearyl alcohol has a comedogenic rating of 2 and irritancy rating of 1. Both of these numbers come from the 1989 study that used rabbit ears; a "2" means mildly comedogenic and a "1" means low irritancy.

Here's the catch: rabbit skin is more sensitive than human skin and throws a lot of false positives. A 1996 reappraisal found that ingredients rated 1-2 in the rabbit ear tests are generally safe for humans.

Remember comedogenic ratings are unable to assess the entire formula of a product or how it will react on your skin. Just be sure to patch test if you are unsure about certain ingredients.

This ingredient is not fungal acne safe. Cetearyl alcohol is a fatty alcohol with chain lengths that fall within the range that Malassezia can metabolize.

A 2019 study has also observed Malassezia growth in the presence of this ingredient, confirming it to be not-fungal acne safe.

Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:

The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.

Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

Glyceryl Stearate is made by reacting glycerin with stearic acid (typically sourced from plant oils like palm or coconut). It's an emulsifier, emollient, and mild occlusive.

Emulsifiers help ingredients like oil and water stay mixed so your formula stays nicely blended and uniform in texture.

This ingredient is typically used in concentrations between 1-10%. Studies have found it to be non-sensitizing, non-phototoxic, and non-photoallergenic.

A close cousin of this ingredient is Glyceryl Stearate SE ("self-emulsifying"). This just has a small amount of sodium or potassium stearate added so it can emulsify without a co-emulsifier.

Since this ingredient is an ester of a C18 fatty acid, it may not be fungal acne safe. The Malassezia yeast can potentially metabolize within the C11-C24 range.

Fun fact: The human body also creates Glyceryl Stearate naturally.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

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Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Acrylates/C10-30 Alkyl Acrylate Crosspolymer is a synthetic polymer. It is used to thicken, emulsify, and improve the texture of products.
  4. 04As an emulsifier, it helps stabilize oil-in-water emulsions to give products an elegant feel when applied.
  5. 05It can also form a thin protective film on skin. One study found that a formula using this polymer helped slow down how quickly other ingredients (like DEET) were absorbed through skin.
  6. 06A 2024 study of over 1,300 patients confirmed that sensitization to this ingredient is rare. It is also non-mutagenic and has a clean track record.
  7. 07Decyl Glucoside is a plant-derived surfactant and emulsion stabilizer. It is created by reacting glucose with the fatty acids from plants.
  8. 08Like all surfactants, it works by lowering the surface tension between water and oil. This makes it so that dirt, sebum, and makeup can be lifted off your skin and rinsed away. It also produces a dense and creamy foam.
  9. 09Because it has a neutral charge, it is compatible with a wide range of ingredients and stays stable across a broad pH range/water hardiness conditions.
  10. 10Patch testing has shown it to have the lowest irritation potential among common cleansing surfactants (like SLS).
  11. 11Typical use levels range from 5-20% in rinse-off cleansers.
  12. 12One thing worth knowing: The American Contact Dermatitis Society named the parent family, alkyl glucosides, "Allergen of the Year" in 2017. The prevalence of allergy is pretty low but be sure to patch test if you've reacted to "gentle" or sulfate-fr…
  13. 13This ingredient is fungal acne safe because the fatty alcohol portion of this ingredient is not within the C11-24 chain length that Malassezia can metabolize.
  14. 14Diethylhexyl Butamido Triazone (aka Iscotrizinol) is an oil-soluble organic UV filter that mainly absorbs UVB and a bit of UVA II light.
  15. 15This ingredient is great at preventing sunburn but doesn't cover the deep UVA I range. This is why it's often paired with a UVA filter like Avobenzone or Bemotrizinol.
  16. 16Two of its biggest selling points are efficiency and stability:
  17. 17Most of the other chemical filters are considered "photostable" if they can last for two hours.
  18. 18Because this ingredient is oil-loving, it can sit neatly into the oil phase of emulsions and shines in water-repellent/water-resistant formulations.
  19. 19The EU and Canada allow it to be used up to 10% and Japan allows it up to 5%.
  20. 20Unfortunately, it's not yet an FDA approved sunscreen agent so you won't be able to find it in sunscreens in the US.
Source · skinsort.com
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Related product references

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Comparison edit

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