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deneuxben said:

1. my compacting process: For now it is very manual and not optimized at all, I think it leaves air pocket which leads to a crumbly texture.

This is an issue with improper binding. Using fine powdered surfactant with a wetting agent - water in CAPB for example will resolve “air pockets and crumbly texture”. Binder is usually used at 4-6%. Use too little and it crumbles. Use too much and it stays wet and soft.

2. The chemical bonds: I think, if the bar wears off so much is that it does not have enough internal cohesion to resist to the surface attraction/tear (when you leave it on a surface while wet)

Look at Sodium Lactate/Sodium Chloride and what they can do in Syndet Bars. 

For point No. 2, I will try if adding some emulsifiers help in this ? after all, I have water loving molecules mixed with lipophilic compounds. Emulsifier does not sound so bad to me to hold them together, no ?

Yes, adding an emulsifier is a great idea. I have used BTMS, Polawax, Lanette N, Glyceryl Stearate with great success in these types of bars. BTMS is best for a light conditioning shampoo. 

For point No.1: I am a bit confused. I agree with you to do simple formula to develop a good base, but in this case I though that the purpose of the clay or starch was to enhance the compacting step (I guess the fine powder fills the small wholes). So I understand that you say it is not a must to develop a good base already, isn’t it?

Different powders compact differently. I certainly don’t believe that these types of starches and clays will help you create a compact mixture. 

For liquid surfactant (like CAPB), I am using coco glucoside, in small amount, like 4%. I was thinking to take that off. I added it to make a milder synergy with SCS, but I wonder if it does not make the product more sticky in a way, or help in any way at all… DO you think this is crucial ? I mean, if this is for the water content, I can add the water alone.

Glucosides weaken the structure of the bar. I don’t know why, but that has been my experience (even at 2%) The bar will snap in half even after a few uses.

I am going to go read that book, chapter 4

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So 2.0 % Carbopol Aqua SF-1 is sufficient to thicken this formulation. I don’t think I would go lower.

10 % Decyl Glucoside
15 % CAPB (30% active)
2% Cocamide DEA

2% Carbopol Aqua SF1

0.20% EDTA 4 Na
2.0% Polyquat 7
0.12% BAC

Great hand feel, doesn’t run off on hands, no stickiness and rinses off well. 

I noticed quite a loss of viscosity when adding the Polyquat 7. I will play with the percentage between 1.0-2.0% to find a proper target amount. I will also knockout the Cocamide DEA to see if I can remove it altogether.

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I have used a green color mix for my Apple scented alcohol sanitizer and it contains Blue no 1. There has been no color change whatsoever. 

I am using 70% EtOH (Drinking quality, not denatured). The batch is from March and no issues whatsoever. 

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Well, if you have been using strictly the noodle form of SCS, you are already looking at an easy improvement using powdered form. Binding noodles is not effective. You need around 45-55% powdered surfactant.

My preference is SCI with some SCS noodles blended in.  In fact, many of the DIY recipes are completely off. Your best bet is to shut these out. I like to use 30% Active CAPB. The water content will act as a binder. There are things like colloidal silicon dioxide that increase cohesion but if your ingredient ratios are right, you will not need it.  

Shampoo bars are Syndet bars and follow the same guidelines already established by the industry. 
 
Read Chapter 4 of 

Soap Manufacturing Technology, Second Edition. 

This is crucial reading if you plan to make the best possible product.

Also, a final tip for you is to first develop a base formula without any additional ingredients like clays and starches. 

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Ah! so there are potential problems using FD&C Blue no 1? I guess that is why Lysol uses a different blue for their multi-use product. 

I think you might have save me a lot of hassle, chemicalmatt. 

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avena sativa kernal flour (50 microns)

Do not waste your time with this! Unfortunately I did. I was designing a rice and oat creamy facial exfoliant syndet bar. I had the marketing story figured out.

I started testing the material at 1.5%. It made the bar weak and left a sticky feeling on the skin. Even at 0.1%, it compromised the integrity of the bar. I eventually tried using the Avena Sativa Oil instead and just decided to shelve this idea.  

I was able to come to these conclusions because I had a solid baseline formulation. This is something I believe you are missing. Shampoo Bar/Syndet bars are very sensitive to the slightest change and you do not necessarily have a solid formulation to start with, 

Also, the faster you realize that most of the ingredients you think are functional in a shampoo are actually just claim ingredients (Fluff), the more you will be able to concentrate on the proper formulation of a syndet bar. 

As of last September, I had never formulated a single cosmetic product. I do have a background in compressed solid products so I had an advantage when starting out, but it took many tries to come down to a proper base formulation. 

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I knocked out the Carbopol SF-1. I will be attempting another formulation with half the amount of Carbopol. Lubrizol recommends 4.0% min but I think that is not needed with this formulation. 

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Here is a patent I find very interesting:

https://patents.google.com/patent/WO2014097005A1/en

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The same surfactant formulation using Carbopol SF-1 did not give a sticky feel. It does seem to “spread” and rinse-off as easily on the hand.  

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Tried the following:

10 % Decyl Glucoside
15 % CAPB (30% active)
2% Cocamide DEA

2.0% Polyquat 7
0.12% BAC

Clear gel, no rheology modifier. I like Polyquat at 2.0%, significant improvement over 1.0% and similar to 2.5%. 

Viscosity needs improvement but not by much. Product “rinsability” is not as good, can leave a slight sticky feel between fingers if hands not rubbed vigorously enough. Hopefully the EDTA 4 Na will help. 

[Cafe33]

Tried the following formulation 

10 % Decyl Glucoside
15 % CAPB (30% active)
2% Cocamide DEA

4% Carbopol Aqua SF1

2.5% Polyquat 7
0.12% BAC

Too viscous, almost paste-like. Great, smooth hand feel however hardly any foam. I will drop the Polyquat 7 to 2.0%. I will also test this formulation without thickener. Waiting on EDTA 4Na. Hopefully that will boost the foam.  

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Ha, exactly. What is frightening is that this was a presentation for a purchasing manager at a big box (american) store. The quote was for 60,000L of Alcohol hand sanitizer. We lost the bid. 

The video they sent the purchasing manager is a demonstration of their gel vs another brand. One can be ignited with a flame, and other one does not catch on fire. That was the selling point.

What is really frightening is that I recognized the brand on the shelves of a nationwide pharmacy chain. It is a real mess. 

Luckily, there is a large shipment of corn based Alcohol coming from the USA and it has brought down the price significantly. We will see if that changes the tide. 

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Yes Belassi, there is even a video of company trying to sell their gel by showing that it is not flammable. They claim there is a fire retardant of some kind.

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BAC is quite a good solubillizer on its own from my (limited) experience.

I have straight Decyl Glucoside as well as Plantapon TF (Decyl Glucoside, Polyglyceryl-10 Caprylate/Caprate, Coco-Glucoside and Glyceryl Oleate). The foaming with this blend is not all that great.

The Plantapon has an acidic pH since it contains some citric pH, most likely not compatible with our active?

What should be the target pH for a final product containing Benzalkonium? 

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Okay yes, I was so enthusiastic about trying this form of Carbopol that I misinterpreted the term compatibility. The Lubrizol document is talking about compatibility in the sense of stability not mode of action. 

An excerpt from Antisepsis, disinfection, and sterilization / Gerald E. McDonnell:

“The antimicrobial
efficacy of QACs can be negatively affected in
the presence of hard water (if in a diluted
product), fatty materials, and anionic surfactants (including soaps); this varies depending on
the QAC type and formulation.”

So maybe Belassi’s suggestion of D-Limonene would help the efficacy of soap in a multitude of ways. 

I have some Decyl Glucoside, I wonder what would be an appropriate amount to use alongside CAPB.

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Thank you Chirag. I will eliminate any additional preservative. Thats what I thought but was unsure.

From the literature on Carbopol SF-1

Cationic Surfactants

As a general rule, cationic surfactants may have
limited compatibility with Carbopol Aqua SF-1
polymer. Low levels of cetrimonium chloride
have been shown to be compatible with the
polymer in a shampoo formulation. 

https://www.ict.unesp.br/Home/sobreoict/departamentosdeensino/odontologiarestauradora/lipq-laboratoriointegradodepesquisa/carbopol-aqua-sfi-ilovepdf-compressed.pdf

So would this apply to benzalkonium? I would imagine a low level of Cetrimonium Chloride would be 0.3%. So perhaps 0.10-0.12% Benzalkonium Chloride would be compatible? Any thoughts?

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I just made a first sample of an antimicrobial hand soap/Shampoo. It was done in haste, specifically to test the carbopol Aqua SF1 I just received.

SLES - 28% (29% active)
CAPB - 15% (30% active)
Carbopol SF1 - 4.0 % (1.2% active)
Triet. - 1.2%

EDTA - 0.15% 
Polyquat 7 - 1.00% 
Purple Mica - 0.15 %
BenzAlk - 0.23% (too high I know)
Fragrance - 0.1% 
Germall Plus - 0.5%

Viscocity is excellent. Better than expected with the minimum amount of suggested Carbopol. No Salt or Back Acid titration was used so far.  

I wonder if the BenzAlk and Polyquat are compatible with a SLES-CAPB-Salt system without the carbopol?

At what percentage would the BenzAlk be self preserving?

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Those are good suggestions Belassi. I did something similar to test around 15 different colors but for solid products, so I used a small amount of water and Baking Soda. I was able to get multiple shades by simply adding virgin baking soda to my stock solution. 

Some colors are distinctly different with solid products vs liquid. 

To the OP, if you are looking for a nice orange color try D&C Orange 4. 

At 0.1% , I managed to color some Syndet Bars (unpressed yet!) as you see in the picture. In a liquid product, I think 0.05% would be a good starting point.

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I have used 12% CAPB with 8% SCI, and no separation was noted months later. What is your reference for using so much CAPB? 

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That’s a terrible shampoo bar formulation which will be impossible to press. I have made syndet bars(not for hair) using around 30 % of various waxes (mainly stearic acid) and the foam was excellent using a combination of SCI/SCS/CAPB or SCI/SLSa/CAPB.

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I wanted to share the price info with you (I think you had mentioned 168 USD for 5 gallons?!) I do not know if they will ship to the USA.

Also, 4.73 USD was the price for 1 kg pack size. I have not inquired on larger pack sizes but from my experience, they can go down by 20% or so even purchasing as little as 5-10kg. 

Either way, I have sent you the complete info by private message. 

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Hi David, I wanted to share that there is a distributor here in Mexico for Coconut Fatty Acid, and it is 4.73 USD per Kg (with a MOQ of 1 kg). I know it is late in the conversation but I am following your thread.  

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Aerosil 200 (Silicon Dioxide) works extremely well for Jojoba oil. 

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Encapsulation of your fragrance is a nice way to prevent it from interacting with sensitive components of your product. I had a syndet bar with Lime EO which attacked the green color within around a week. It turned brown and the smell was also altered. By even partially encapsulating the fragrance, the new formulation is still bright green with an unchanged scent around 6 weeks later at room temperature (30C) completely open to the air. 

I tried the same thing with Orange EO, dissolving it in cetyl alcohol with quick cooling followed by a sort of wet granulation using Carbomer and H20.  

Anyway, these processes are very popular with detergents and fabric softeners. Many patents are available on the subject. Look for the ones that use Silicon Dioxide as a flow and drying agent.

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If you have never attempted this formulation, perhaps its time to go back to the drawing board. 

SCI chips are not so fun to melt. The chips can also contain Stearic Acid depending on the manufacturer. The fine powder is easier to work with if you have regular non industrial equipment. 8% SCI dissolves in H20 with fairly high heat alongside 10% CAPB. Adding 10-12% SLSa (which dissolves well) will create a fairly viscous clear solution which is suitable for a hand wash. It falls into the “creamy sulfate free hand wash” category. 

It will be expensive but nowhere near the $10 cost you are looking at with your formulation. Also, 1% EO seems high, I am making hand soaps at around 0.5% and it seems to be on the high side.