Syndet shampoo bar - any tips for forming a smooth looking bar?

[DeeAnna]

I just made my first test batch of a shampoo bar using synthetic detergents (syndets). DH and I have washed our hair once each with this bar, but so far so good.

My recipe is based on info from Cathy at The Dish (see http://www.soapdisharchives.com/forum/index.php?showtopic=22602&st=25#) as well as advice from Susan (swift crafty monkey) about her syndet shampoo bars (see http://swiftcraftymonkey.blogspot.com/2010/06/shampoo-shampoo-bars-overview.html and http://swiftcraftymonkey.blogspot.com/2010/06/shampoo-conditioning-shampoo-bars-for_03.html ) Between those two ladies, I think I'm in reasonably good hands as far as the formulation goes.

I'm still at a loss, however, about how to form the syndet mixture into an attractive bar. Most of the bars I see for sale on etsy and other websites are rather rustic looking and I now know why.

There are two ways these bars are made -- one is like a bath bomb where the solid powders/flakes are mixed with a bit of liquid and pressed into a mold. The "bath bomb" type of bar has a sandy look:

Ponte Vedra Soap Shoppe:

Ponte Vedra recipe and method: http://pvsoap.com/solid-shampoo-bar-made-with-sls-needles/

Lush:

The other method is to melt the syndets and other ingredients to form a homogenous paste that is then pressed into a mold. This paste is really really sticky and has to be glopped, not poured into a container, much like a soft shave soap. Most bars made this way look like this:

Alaiyna B Bath and Body:

But the shampoo bars by Scenter Square on Etsy look smooth and refined, like this, and I really like the look:

Does anyone have some tips on how I might get this smooth, polished appearance?

 

[Dahila]

I have the same problem DeeAnna my bars are ok but not smooth ........

 

[doriettefarm]

I'm trying to figure out the same thing DeeAnna. I've been using a tweaked version of swift's shampoo bar recipe and mine turn out more rustic than smooth (like pic#3). I've only made 3 batches but the most recent batch was probably the most homogeneous looking of the 3. I do wonder if using the powdered form of SCI would melt down smoother (like pic#4) instead of the prills I've been using. Which version do you have?

 

[doriettefarm]

Here's how mine looks when melted, poured & unmolded

 

[DeeAnna]

According to my order and the label on the product, I have the prill form of SCI. I am used to a prilled chemical looking like small beads that flow really easy, but honestly this stuff looks and acts pretty much like a fine powder.

My bars look pretty much like yours do.

The basic recipe I used was fairly similar to Cathy's with a syndet base of Sodium Lauryl Sulfoacetate (SLSa powder), Sodium Cocoyl Isethionate (SCI powder), and cocamidopropyl betaine (CB liquid). The other ingredients were emulsifiers/conditioners (e-wax and conditioning emulsifier), thickener (stearic acid), hemisqualane (an alternative to silicones), coconut oil, preservative (liquid germall plus), panthenol, and fragrance.

I melted the SCI with the CB to get the SCI melted. That went pretty good. Then I added all the other ingredients to the SCI-CB mixture and heated that until the SLSa melted. The mixture was like stiff, lumpy mashed potatoes at first until I realized I needed to get it heated even more -- above the melt temp of the stearic acid (155-160 F, 68-70 C). Otherwise I was going to have little annoying stearic lumps in the bar. The extra warmth made the mixture more pliable, but it certainly wasn't ever going to flow at all!

I suppose I could add more liquid surfactant (cocamidopropyl betaine) to get a more flowable, moldable product. I actually did add a little extra CB than Cathy's recipe called for, but I realized that more liquid = more softness. I need to see how the bars dry down over time, but I can see it's probably best to use the least amount of liquid possible and still get everything melted and mixed properly.

 

[DeeAnna]

In looking more closely at the Scenter Square ingredients list, I see she is using several ingredients -- Glyceryl Stearate, Sodium Steroyl Lactylate, and Butylene Glycol -- that function as emulsifiers or humectants and/or texture modifiers. I wonder if the polished, smooth appearance of her bars lies with the use of these additives. Just guessing -- I have no experience with these. Regardless of how she's doing it, I'm impressed!

Ingredients: Sodium Cocoyl Isethionate, Disodium Cocoamphodiacetate, Sodium Lauryl Sulfoacetate, Silk Amino Acids, Kokum Butter, Cetearyl Alcohol, Behentrimonium Methosulfate, Cetyl Alcohol NF, Fragrance, Cocamidopropyl Betaine, Meadowfoam Oil, Glyceryl Stearate, Sodium Steroyl Lactylate, Panthenol, Butylene Glycol, mineral colorant. Source....

 

[BattleGnome]

I don't make syndet bars but based on what everyone is saying, would adding glycerin smooth it out a bit? Or even just plain water with a bit of a cure time tacked on?

I use Pert and there is glycerin on the ingredients list, my husband uses the soon of Head and Shoulders which lists water as a first ingredient. Yea, there's a big difference between liquid and solid shampoo but if it's controlled like with CP then it might be possible?

(This also assumes I understand syndet bars. I haven't done much research on them due to a hatred of what SLS/A does to my skin)

 

[DeeAnna]

Yes, glycerin could be added to a shampoo bar, but there's a limit to what will work well. Too much and the bar will be soft and perhaps permanently sticky, because the glycerin will never dry down and will attract water from the air.

The liquid syndet I used (cocamidopropyl betaine) supplies some water. I actually added more CB than my original recipe called for because I wanted the mixture to be less sticky and gloppy when I made it. Adding more CB made the mixture softer, but it was still sticky and gloppy, so I'm not sure I improved matters much.

But your suggestion, BattleGnome, gives me a thought -- Another ingredient to consider would be sodium lactate. I do know it makes HP soap smoother and more pourable and hardens finished bar soap, whether HP or CP. Maybe it would be helpful in a shampoo bar -- it might be worth studying up on it and giving it a try. I have some but don't use it much. I'm trying to stick as much as I can with soaping and lotion making ingredients I already have, rather than track down and buy yet one more oddball additive.

***

As far as SLS and SLSa being irritating to use -- yes, that's very true. I've learned over the years that any amount of SLS (sodium lauryl sulfate) and I don't get along -- it causes my scalp to get itchy and my hair to feel harsh and dry. If I am in a situation where I have to use a shampoo with SLS, I'll seriously consider not washing my hair.

I understand from Susan (swift crafty monkey) that combining two or more syndets of different types (anionic, cationic, nonionic) reduces the irritancy of the shampoo. Many commercial shampoos will often use SLS (cheap, lots of lather, cleans well, but high irritancy) with at least one dissimilar syndet to tame the SLS down, but that's not enough taming for SLS to work with my skin and hair.

At this point, I'm not sure about how SLSa and I will get along either. SLSa makes lots of big fluffy bubbles, which is probably why it's a popular sub for SLS, but I know it can be almost as irritating/drying as SLS.

I chose SLSa and SCI and cocamidopropyl betaine for my first try based on Cathy's and Susan's recommendations. I think you could easily omit the SLSa and use just SCI and cocamidopropyl betaine. If my understanding is correct, this combo will probably make a creamy, low lather that is very gentle.

There are many other syndet combinations out there -- far too many for me to digest -- so I'm going to stick with some combination of these three for now.

 

[Soapmaker145]

Ingredients: Sodium Cocoyl Isethionate, Disodium Cocoamphodiacetate, Sodium Lauryl Sulfoacetate, Silk Amino Acids, Kokum Butter, Cetearyl Alcohol, Behentrimonium Methosulfate, Cetyl Alcohol NF, Fragrance, Cocamidopropyl Betaine, Meadowfoam Oil, Glyceryl Stearate, Sodium Steroyl Lactylate, Panthenol, Butylene Glycol, mineral colorant. Source....

I suspect the cocoamphodiacetate is what made it smoother. If it is, you might want to consider if it is worth using because it is not readily biodegradable as opposed to cocamidopropyl betaine which is degraded in under 24 hours. I wonder if you could add a small amount of propylene glycol and/or glyceryl stearate to make it more fluid and homogeneous. I've never made a syndet. My suggestion is based on what I would try.

 

[doriettefarm]

If the powdered SCI doesn't melt smoother than the prills, Soapmaker145's guess seems reasonable to me. I also used cocamidopropyl betaine and have no experience with the Disodium Cocoamphodiacetate stuff. I have ordered shampoo bars from a different etsy seller (GetLathered pic below) than DeeAnna's 'smooth' example and hers are pretty smooth as well. They perform well and also seem a bit harder than mine. The similar theme in comparing recipes does appear to be the liquid surfactant.

 

[DeeAnna]

Hmmm. Things to think about. Thank you for the suggestions.

Another thought is using pressure to compact and smooth the mixture. I made a solid conditioner bar tonight -- another first time experiment. I put the mixture into the same mold --a small plastic container -- that I used for the shampoo bar. THe conditioner bar was also going to be rather rustic like the shampoo bar. I started wondering what I could do to improve the appearance. I found a small cup that would fit inside the mouth of the impromptu mold. I put plastic wrap over the conditioner mixture and then pressed down firmly with the cup. That made the top surface of the bar shiny and smooth -- actually looks pretty decent. I have yet to unmold the bar, so I don't know what the rest of it looks like, but I have hopes. Will keep ya posted.


Update, 12 hr later -- The unmolded conditioner bar has a smoother surface overall, having been pressed firmly into the mold. Still room for improvement, however. In particular, I need to get rid of pesky air pockets. The conditioner bar is formulated quite differently than the shampoo bar, so I need to try this idea with the shampoo recipe to see if simple pressure is helpful for that one too. I also think a very simple mold that is entirely smooth (Get Lathered) or has only a shallow design (Scenter Square) is another key.

What I especially enjoy about this little project is formulating the two recipes -- shampoo and conditioner -- so they compliment each other. Even if I never get that polished elegant look to the bars, I'm still having fun with this.

 

[Dahila]

mine is not good looking one either DeeAnna, but it does the job

 

[Dahila]

DeeAnna tell if reverse osmosis water can be used as replacement for distilled water , please? Sorry for hacking the thread,,

 

[DeeAnna]

I'd use RO water if I couldn't get distilled, although I'd choose distilled first if I had both to pick from. I'd definitely use RO over tap water. Go for it, Dahlia!

 

[Dahila]

Thank you so much DeeAnna

 

[doriettefarm]

We must be on the same brainwave DeeAnna! I made solid conditioner yesterday and it seems much easier to melt/pour smoothly than the solid shampoo. Once again I used the guidelines on swift's blog to formulate.

 

[JillGat]

Wait.. are those BRAIN molds?

 

[DeeAnna]

Yes, I agree the conditioner version is much easier to get a polished look than the shampoo version. I have made 3 mini batches (100 g per batch) of the shampoo so far, all with minor tweaks, and 2 mini batches of the conditioner. Very pleased with both.

A 45-50 gram shampoo bar gives me and DH about 1 month of shampoos. The conditioner lasts much, much longer than the shampoo, even though I'm also using it as an in-shower lotion bar. It has a slight edge as a hair conditioner but is also nice as a non-greasy silky summer-weight lotion for skin.

Here's my last recipe for the syndet shampoo bar:

Simple shampoo bar (syndet based)

Heated phase
Solid fat … 3% … Possibilities: tallow, lard, palm, mango butter, coconut, babassu, etc. Don't go overboard on fats -- this is a shampoo not a conditioner.
Conditioning emulsifier … 3% … This is a generic version of the emulsifier BTMS. Can use emulsifying wax (e-wax) instead.
Stearic acid … 3% … Thickener. Could substitute cetyl alcohol. Makes the bar a bit less water soluble so it doesn't dissolve too easily.
SCI … 28% … Sodium cocoyl isethionate. Surfactant, powder. Mild. Creamy foam.
SLSA … 33% … Sodium lauryl sulfoacetate. Surfactant, powder. Not quite as mild as SCI. Adds bubbles.
Cocamidopropyl betaine … 26% … aka CAPB. Surfactant, liquid. Do NOT use more CAPB, even though you might want to.

Heated phase OR cool-down phase
Preservative … 0.5% … Preservative is NOT OPTIONAL. I use phenonip and put it in the heated phase. Liquid Germall Plus is fine, but is heat sensitive, so include it in the cool-down phase. See notes below for more.

Cool-down phase
Panthenol … 2% … Optional. If you omit this, add this % to the SCI or SLSA.
Fragrance … 1.5% … Optional. If you omit this, add this % to the SCI or SLSA.

For a pale to medium color -> add 1 drop of liquid colorant per 100 grams of product. Add to the heated phase. I use ultramarine blue or green chromium oxide in glycerin.

Put all ingredients for the heated phase (including colorant if using) into a microwave safe container. Microwave in 15-30 second bursts. Stir thoroughly after each heating. Repeat until all ingredients are all melted and there are no variations in the color (if you're using colorant).

When fully melted and mixed, the product will be a sticky paste. Do NOT add any water, cocamidopropyl betaine, or other water-based ingredients to loosen the product.

Stir in the cool-down ingredients when the temp is below 120 F (50 C). Immediately glop into small containers. I make about 50 grams per bar -- this is about 1 month of shampoos for me and my DH. Put into the refrigerator to cool and firm up. Unmold and let the product dry for a day or two before use.

Notes:

SCI and SLSA are dusty and very irritating to the nose and lungs. When weighing and mixing these products when they're dry, be careful -- work under a vent hood, work outdoors, or wear a respirator.

SCI comes in a flake, noodle or "prill" form. The first two forms may have stearic acid in the product. The prill (a very fine bead) does not, and this is what I am using and what this recipe is based on. If you get SCI with stearic in it, you may want to adjust the recipe.

It may be possible to use SCI for all of the SLSA if you want to try only one solid surfactant. I haven't done this, but I would first try only SCI if I thought I wanted to simplify further.

The temp limit of 120 F (50 C) is critical if using Liquid Germall Plus. If using Phenonip which goes in the heated phase, then the only cool-down ingredients are the fragrance and panthenol. Temperature isn't too critical for these ingredients, so I add them right after I know the mixture is fully melted. That lets me get the paste in the molds as soon as possible when it's warm and easier to handle. The trade-off is there might be a little less fragrance in the finished product, but that's okay with me.

I want to acknowledge that this recipe has been adapted from one provided by "Cathy" at The Dish. My thanks to Cathy for her generosity!

This recipe is also provided in this thread but I'm repeating it here, cuz I'm the OP for this thread.

 

[BrewerGeorge]

How about a mechanical solution? Have you seen those vibrating wands used to drive out air when pouring concrete? Maybe some kind of shake table would help.

 

[Dahila]

BG no but as soon as it sets up , I use my soap planer and sharp knife, they look almost decent now