SLS in CP/HP soap

[paragon]

(I've never been one to shy away from controversy.)

I hate what sodium cocoate does to my hands. I have a 0-2% superfat bar with at most 20% coconut oil. It doesn't merely dry my hands; it makes them feel like the skin is rough and has been abraded. The bar passes the zap test even when I cut into the inside (and does not leave a slippery lye feeling on fingers), but it makes my skin feel like I've washed dishes for an hour with pure SLS.

Just kidding about the SLS (also known as SDS), because in fact I do wash dishes with mostly sodium lauryl sulfate. It typically doesn't mess up my skin. I know this chemical has a bad reputation online, but from what I've read about it, it's considered okay to leave on skin at up to 1% of a formulation like a cream, so it should be okay at higher rates in a soap combo bar which is washed off. And from what I've read about traditional soaps, they are irritating on skin. My experience bears this out: Dr. Bronner's castile soap did such a number on me that I thought I had eczema.

I was going to make a soap that simply had no coconut oil, but I worried about it not making foam or not being effective as a soap. I realized instead, I could make a combo bar (soap/syndet) by substituting SLS instead of coconut oil. I decided to use just a bit, as insurance to be sure the soap would soap.

The recipe I chose was:

• 60% canola oil
• 30% lard
• 10% olive oil (just to use it up)
• 5% castor oil

• 2% SLS relative to the oil weight
• 2% trisodium citrate as preservative (see the Kevin Dunn study) and to help if the water gets a bit hard
  
• 2% sodium acetate to help make the bar hard
  
• 0.5-1% EDTA as preservative (chelating agent) and to help if the water gets a bit hard
• A big pinch (what an unscientific measurement) of salt thrown in on impulse, since I was worried about the bar being too soft. The batch was just 115 g oils, so a big pinch is not nothing.
  
• 0.1% TBHQ (was supposed to be BHT but the seller sent me the wrong oil-type antioxidant)

The lye is over 99% pure and I chose a 5.5% superfat.

I used a strong ginger tea instead of most of the water, and 2% essential oils. There is no way I'm going to be able to wait for this to cure! I'll post back in a day or two to say how it works, after using it in the shower and on my hands.

 

[shunt2011]

Most of us make soap to avoid using that. Your issue with your soap you find drying is too much coconut and too low of a SF. Lower your coconut to 10-15% and up your SF to 5-6% Can’t help you with the use of SLS.

 

[Dawni]

Haven't ever made anything with SLS... But I will agree that 20% coconut with only 0-2% SF won't work for me either. My recipes have more like 15-17% coconut and 2-4% SF. Just throwing it out there...

Also, with a sufficient cure time, good soaps will lather well.

 

[paragon]

I didn't take notes on every batch, but I think I have gone as low as 12% coconut oil and found that irritating. (Almost every batch was low SF, since I didn't realize I had fairly pure lye.) The principles surrounding coconut oil drive me nuts: we depend primarily on one oil to ensure good lather and cleaning power, but it wrecks skin if you use too much or make the wrong SF. This is the type of dangerous chemical we should be avoiding, not synthetics!

Sorry, I had to get that off my chest, and I recognize nobody here else feels that way. I also recognize that many people use it without issue.

 

[paragon]

Okay, my initial observations on this recipe:

• It is gentle on skin, even though my skin is still a touch irritated from washing hands with a more typical soap in the previous days.
  
• It doesn't feel like it's leaving a film on my skin, unlike many of the more traditional soaps I made.
• The oleic acid is too high at 55%. The first hand wash gave ropey slime, but subsequent hand washes did not. I should see how it behaves after a cure.
• Never make one bar of soap! Always make two, so you can use one and let the other cure.

I would say the experiment was a success. I will tentatively call this a soap, just as a Belgian beer made with 10% sugar in place of grain is still called a beer. I'm not selling, anyway.

 

[KiwiMoose]

Maybe you are slightly allergic to coconut oil? Some people are. How about trying Babassu?

 

[Arimara]

How old is your soap?

 

[paragon]

In the shower, this soap is ridiculously soluble and feels very cleansing, yet rinses off more easily than my last soap (high lard, some coconut). I'm not sure if the SLS has any effect. Are all bastille soaps like this? I wasn't terribly impressed with the visual appearance of the lather, but as a mechanical mechanism--to help the cleaner adhere and spread to more surfaces--the soap was very good. On skin it felt like a thicker, more adherent version of body wash.

Maybe you are slightly allergic to coconut oil? Some people are. How about trying Babassu?

Thanks for the thought, but I've eaten too much coconut oil to think I'm allergic. The only other explanation I can think of is that the zap test is not accurate. I did cut into a previous bar and lick the inside without discomfort.

How old is your soap?

It's too young! About 48 hours. As it cures, it will become less soluble, but what other changes can I expect? I surmise that cure affects hand washing more than showers, since in a shower you rub away so much of the bar that you will always get a homogeneous mixture of soap (not depending on the crystal structure).

 

[Arimara]

If the soap is only 48hrs old, you can't really complain about its harsheness yet. It's too young. If the soap was cured for at least 6 weeks, then you could complain if it feels harsh (we'd still suggest you hang on to the bar and test it after some more time passed). Give it some proper time to cure and keep us posted. If need be, you have the materials necessary to make confetti soap if it is a failure.

@KiwiMoose Sodium cocoate is not coconut oil, only a derivitive via chemical reaction. If paragon used a refined variety, there's actually less of a chance that an allergic reaction would occur. Usually refined oils have way less of the unsaponifiables that trigger allergic reactions.

 

[paragon]

If the soap is only 48hrs old, you can't really complain about its harsheness yet. It's too young. If the soap was cured for at least 6 weeks, then you could complain if it feels harsh (we'd still suggest you hang on to the bar and test it after some more time passed). Give it some proper time to cure and keep us posted. If need be, you have the materials necessary to make confetti soap if it is a failure.

This soap is not harsh. The other soaps I made which contain coconut oil are harsh, except the one that had high SF (due to having used years old improperly stored lye). And soaps don't need weeks to fully saponify unless you did something strange.

 

[Arimara]

This soap is not harsh. The other soaps I made which contain coconut oil are harsh, except the one that had high SF (due to having used years old improperly stored lye). And soaps don't need weeks to fully saponify unless you did something strange.

There's a huge difference between saponifcation and curing. Saponification is when lye and oils become soap. Curing is the physical and chemical changes that happen in those bars over time in which soaps loose water, harden up and (usually) mellow out. A soap can be completely saponified in as little as a few hours for cold processed soap and an hour for hot processed. BUT, both types of soaps need at least 4-6 weeks cure time for it to at least start become good soap.

 

[paragon]

There's a huge difference between saponifcation and curing. Saponification is when lye and oils become soap. Curing is the physical and chemical changes that happen in those bars over time in which soaps loose water, harden up and (usually) mellow out. A soap can be completely saponified in as little as a few hours for cold processed soap and an hour for hot processed. BUT, both types of soaps need at least 4-6 weeks cure time for it to at least start become good soap.

Oh, I was unaware the harshness could change during curing. I'll look out for that and see if I can notice it in the future. Though I wonder if that's just because of solubility--a more soluble soap could be more harsh due to more product being applied.

 

[shunt2011]

This soap is not harsh. The other soaps I made which contain coconut oil are harsh, except the one that had high SF (due to having used years old improperly stored lye). And soaps don't need weeks to fully saponify unless you did something strange.

You are wrong in you statement. Soap does need to cure, it's not just about saponification. Your high CO soaps need to cure 3-6 months to be able to tell if they are a good soap. High CO soaps like your need a cure to become more gentle, harder, though they will always be more soluble in water.

A well balanced soap, I cure 6 weeks. My salt soaps I cure 6-12 months and prefer them to cure even longer.

I would much prefer a well balanced bar of soap than add SLS. If you are sensitive to CO, which is possible you can try Babassu or PKO.

Using newly made soap is not a true judgement of what it's true potential is.

 

[IrishLass]

For what it's worth (getting back to the original question), you can definitely make a CP/HP soap with SLS. I know of a few folks who have done it successfully and it's actually on my list to try as a fun, experimental thing. I want to try it with a high% tallow soap.


IrishLass

 

[Arimara]

Oh, I was unaware the harshness could change during curing. I'll look out for that and see if I can notice it in the future. Though I wonder if that's just because of solubility--a more soluble soap could be more harsh due to more product being applied.

Solubility has nothing to do with how harsh a soap is; it's just a measure of how fast your soap melts in water. To start to have an idea of how harsh a soap may be, you have to look at the major fatty acids that make up the various soap soap oils. You should take a look at the properties of your soaping oils in a soapcalculator and look more into what properties different oils take on in soap.

Coconut oil is considered a cleansing oil when saponified. Even other synthetic cleansers rely on coconut for cleaning power. When you do not properly account for coconut's cleansing properties (by capping the amount you use or raising your superfat), you can very well get a horribly harsh soap. That does not mean that a high coconut oil soap is going to be always harsh. Some people here make salt bars, which rely on high amounts of coconut oil and a high superfat but after at least 6 months of curing, the soap begins to shine.

 

[paragon]

To clarify, I've never made a high coconut oil soap. The soaps I find irritating contain 15-20%.

If some soaps become less harsh during cure, that's news to me! Is the physical process understood? My intuition says crystallization shouldn't affect harshness, but hydrolysis of triglycerides might.

 

[Mobjack Bay]

To clarify, I've never made a high coconut oil soap. The soaps I find irritating contain 15-20%.

If some soaps become less harsh during cure, that's news to me! Is the physical process understood? My intuition says crystallization shouldn't affect harshness, but hydrolysis of triglycerides might.

Read about what happens during “the cure,” here:
https://www.soapmakingforum.com/threads/cure-time.35831/page-3#post-634104

 

[Dawni]

If some soaps become less harsh during cure, that's news to me! Is the physical process understood? My intuition says crystallization shouldn't affect harshness, but hydrolysis of triglycerides might.

I don't know about the long words but from experience, which isn't even too long to begin with, I know that ALL soaps become milder after a cure.

Unless of course you're allergic to one ingredient or another or your skin simply doesn't like it even after a year's cure (Castile I'm looking at you lol).

I've even forgotten to superfat once and with a long cure that soap is now one of our favorites.

There's no harm in trying the SLS. More power to you. We're just saying don't be too quick to judge your soaps if they're younger than at least 6wks. You might be surprised.

 

[paragon]

Read about what happens during “the cure,” here:
https://www.soapmakingforum.com/threads/cure-time.35831/page-3#post-634104

Thanks for the link. Doesn't explain how soap could become more mild over time, though. That process determines the relative proportions of different fatty acids in the first and subsequent washings within a session. What about liquid soap? That doesn't crystallize, but does it become more mild over time?

Also: **** it, I'm just too sensitive. After a couple days with the new soap I am noticing some dryness in my hands. I'll raise the superfat to 10% next time, but will keep the rest the same.

 

[Dawni]

Maybe this one then?
https://classicbells.com/soap/cure.asp