What's in a shaving soap that makes it better for shaving than regular bar soap Ivory, Irish Spring, etc.?
Fundamental difference betw regular bar soap and shaving soaps?
- Thread starter Brassplyer
- Start date
Shaving soap must have a high amount of stearic acid (which can be derived using many different fats/oils/butters).
A shaving soap requires majority Potassium hydroxide.
This combination is what allows the lather to be dense and stable.
The addition of coconut oil/palm oil/palm kernel oil allow air to be infused into the lather.
Then come all the skin conditioning ingredients, for which there is near infinite choice!
A shaving soap requires majority Potassium hydroxide.
This combination is what allows the lather to be dense and stable.
The addition of coconut oil/palm oil/palm kernel oil allow air to be infused into the lather.
Then come all the skin conditioning ingredients, for which there is near infinite choice!
The amazing thing about a really good shaving soap is that it does not dry out the skin. Lesser shaving soaps, of course do. Bar soaps for bathing are notorious for drying out the skin and also causing people to have rashes and other things like that. there is a huge difference in that regard.
Hi, @nav provided and excellent summary. Adding to that using potassium hydroxide as a saponification agent makes the soap a bit softer, easier to lather and contributes to lather stability. If you see a soap only saponified with sodium hydroxide it's likely just bath soap or bath soap marketed as shaving soap.
Note that you will not always see stearic acid listed on a high quality shaving soap. For example the old tallow version of Mitchell's Wool Fat shaving soap lists ingredients in their post-saponification state after the soap has reacted the saponification agent. Also good soaps can include saponification with both sodium and potassium hydroxide with multiple fatty acids as seen in this example (Tallo, coconut oil and stearic acid).
Mitchell's Wool Fat Shaving Soap Tallow Version Ingredients:
Sodium Tallowate, Potassium Stearate, Sodium Cocoate, Sodium Stearate,
Aqua, Potassium Cocoate, Glycerin, Parfum, Alpha-Isomethyl Ionone, Hexyl
Cinnamal, Limonene, Linalool, Hydroxycitronellal, Lanolin, Titanium
Dioxide, Sodium Chloride, Sodium Gluconate, Sodium Silicate, Tetrasodium
EDTA, Magnesium Sulphate, Tetrasodium Etidronate.
Absolutely right!
Stearic acid can come in the form of many fats and butters. Even hydrogenated oils convert from linoleic acid to stearic acid (eg soy wax).
My soap consists of majorly butters and lesser stearic acid but total stearic acid is still high because the butters are around 40-50% stearic acid.
The higher the potassium hydroxide, the more creamy the lather will be. So 60% KOH will generate a lather that will be slightly less cushiony whereas 80%+ KOH will be thicker and more cushiony (all else being equal).
I personally prefer 60% KOH for myself as it allows for a deeper cut and less post shave shadow.
One fairly common (at least in US) "bar" soap that works well for shaving is Dove MEN+CARE 3-N-1. It says on the package that it can be used for shaving, and (at least for me, anyway) it does indeed work just fine as a shaving soap.
I have used bar soap many times for shaving by just taking the bar and rubbing it directly on my face and neck instead of trying to lather. I have also used body lotion to shave after hydrating my beard quite a bit. You can get a good shave with many things, but that doesn't make any of those things shaving soap.
Excellent discussion!
All I can add is the my worst conclusion about a sub-par shaving soap is, ‘I‘ll just finish this one in the bath!’
All I can add is the my worst conclusion about a sub-par shaving soap is, ‘I‘ll just finish this one in the bath!’
In my experience, bath soaps lack residual slickness, lather stability, cushioning and skin conditioning. All these shortcomings define a lousy lather. These qualities of residual slickness, lather stability, cushioning and skin conditioning are being paramount for a consistent excellent shave, and cannot be separated.
A mediocre shaving soap manifests only "core" qualities. Not enough for consistent, daily, excellent shaves. Lack of cushioning and skin conditioning have subtle consequences and lead to skin irritation and other issues in the long, or not so long, run.
A much better question would be what is the fundamental difference between regular bar soap and good quality shaving soaps? See below.
In my opinion, advocating for shaving soaps that manifest only "core" qualities is equivalent to advocating for mediocrity.
Good luck on you quest to finding a soap that suits your style.
When fund were low when I was young I used bar soap. It worked.
Put small pieces in big coffee cup, made lather, it work ok.
Real shave soap is different, most are better then recycled bar soap.
You can get good shave soap cheap if your not fussy, or picky about the smell.
As I alway shower after shaving, smell is not important.
Put small pieces in big coffee cup, made lather, it work ok.
Real shave soap is different, most are better then recycled bar soap.
You can get good shave soap cheap if your not fussy, or picky about the smell.
As I alway shower after shaving, smell is not important.
I wasn't advocating for anything, simply answering the OP question.
But now that you mention it, are you aware that even stearic acid is actually a very moisturising ingredient?
It's used in many moisturizers to serve this purpose.
What takes away from the moisturising properties is either too much coconut oil or a reaction to any fragrance.
One could make a simple soap with mostly stearic acid, a bit of coconut oil, a bit of butters/castor oil, glycerine and get a fantastic performing soap without any skin drying whatsoever.
In fact, just increasing the KOH in the recipe leads to a nice rich, creamy and non drying lather.
Nothing
I wasn't implying that you are advocating for anything. The quoted posts were used to show qualities of a good shaving soap. In my opinion, of course. That's all.
Rumor has it, there is a member who shaves with bath soap scraps and gets fantastic lathers and shaves.
Fact or Fiction? You decide.
I'll shave with shave soaps. I'll shower with bar soaps. I'll shower with shave soaps. I won't shave with bar soaps.
Fact or Fiction? You decide.
I'll shave with shave soaps. I'll shower with bar soaps. I'll shower with shave soaps. I won't shave with bar soaps.
Fact. And it has been fact since 1973. It works and works well and it costs nothing.
Oh come on! At the very least bath soaps tend to be in the shape of a rectangle or square while shaving soaps tend to be round in pucks that better fit your shaving mug/bowl or sticks that are easier to hold when applying to your face.
Tastes Great!
Less Filling!
Less Filling!
Depends on ones definition of core qualities. The main purpose of lather is to provide slickness to lubricate the shaving process and to moisten ones whiskers as this can reduce the cutting effort required of the blade by up to two/thirds versus a dry beard.
Given that my definition of core shaving performance comes down to three factors, slickness, lather stability and lathering ease. Based on personal preferences there are a number of other factors such as scent, post shave feel/skin conditioning and even the container artwork as some here collect soaps. Open question regarding if cushioning is a real thing beyond just a marketing term that has been discussed in detail on other threads.
Regarding bath soaps the one's I've experimented with, such as Ivory, Dove Men+Care and even Zote (mostly tallow based laundry soap), provided great slickness and were not hard to lather. The main issue was, with the exception of Dove Men+Care, poor lather stability. In fact when at tried a grated mix of 50/50 Dove and Ivory it was an acceptable shaving soap across the core performance areas with good slickness from the Ivory and stability from the Dove. I still prefer my shaving soaps but could live with a blend like this if it was my best available choice.
Based on YMMV/personal preferences there is no reason why a shaving soap with great core shaving performance (my definition) shouldn't be considered excellent. Respect how we each make our own choices based on preferences for the other factors.
P.S. Edit: Just realized we went through much of this discussion in detail a few months ago in the thread linked below. No need to further repeat it. Again ultimately all this comes down to our personal preferences and YMMV. Fully respect yours.
Do Shaving Soap Trace Ingredients Ever Matter or is it All About the Base?
Over the past couple years I've purchased a number of different shaving soaps such as Mitchell's Wool Fat (tallow formula), Tabac (new formula), What-the-Puck, Williams, Arko, Van Der Hagen, D.R. Harris and Cyril R. Salter. All these soaps work well for me and I enjoy the variation in lather...
www.badgerandblade.com
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It's the shaving properties that are important, not just the ingredients.
Bath soap is made to clean your skin. Shaving soap does not have a lot of cleansing power. That is good since it doesn't normally strip all the oil off your face and dry it out.
Shaving soap is made to produce a longer lasting lather that will persist while you are shaving. Bath soap lather is less stable, more bubbly usually.
Bath soaps are hard so they don't melt away too soon. Shaving soaps are softer so you can pick up enough soap on your shaving brush.
As posted above, most shaving soaps are higher in stearic acid and use more potassium hydroxide in place of sodium hydroxide which makes for a softer soap. However, there are exceptions to the rule, such as some French shaving soaps based primarily on palm oil, palm kernel oil and shea butter.
