johnb
Forum Replies Created
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The literature for Cosmedia ATC (which corresponds to the mixture you quoted) states that:
The prime function is as a rheological control additive for applications within the toiletries and cosmetics industries.
It is NOT claimed to be an emulsifier.
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I don’t think that is a good enough emulsifier for the formula stated.
I agree with Bobzchemist that the whole thing needs a careful re-evaluation.
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BTW I’m still of the opinion that this is a very odd formula if its major function is fragrance assessment.
My own (admittedly limited) experience with polymers like Carbopol Aqua SF2 is that they have their own pervasive odour which “leaks through” a number of fragrance types thus giving a false impression during assessment.
I’m also mystified why SLS is used in preference to SLES which is much more soluble.
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Whilst gluconic acid/sodium gluconate would make a good buffer, it must be formulated with great care.
Gluconic acid as normally purchased is a nominal 50% acid. What has to be taken account of is that this comprises an equilibrium mixture of gluconic acid and glucono-delta-lactone equivalent to 50% gluconic acid. It is only after considerable dilution that the lactone hydrolyses to the acid and this takes time.
What it means in practice is that after making a buffer mixture of a certain pH, you will find after a time (hours or days, depending on the concentration) that the pH drifts downwards as more of the lactone is hydrolysed.
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Perhaps if you added the extra water at a different stage in the process it would be more miscible and remain clear - before neutralising the polymer for instance.
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Sandi, depends on what you are trying to achieve.
There are a large number materials which will thicken oils, each with their own characteristics and properties. When combinations of these thickeners are considered, the number of thickening effects is very large.
Another important consideration is if you want fatty or waxy material or a synthetic polymer to act as thickener?
Inform us of what you want to make and we may be able to offer suggestions.
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- - and even after all of this discussion I don’t see an effective emulsifier present.
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If, as you state, you are in the final year of a technical cosmetics course what have you been taught during this time?
If nothing else, you ought to have been instructed how to use the Internet search engines.
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Ascorbic acid is not soluble in oil so the ones you have listed will not contain the material - however much marketing hype tries to convince you otherwise.
Tocopherols (if present) will be only in extremely small amounts.
Whether Tetrahexyldecyl Acorbate and/or Tocopherol have any effect at all in a cosmetic product is a matter of conjecture (and, again, the convincing nature of marketing hype).
I do try not to be cynical in cosmetic matters but sometimes the claims made for the activity of vogue molecules, extracts, snake oils and fairy dust are way, way beyond being reasonable.
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If the main function of this product is fragrance evaluation, I think that the inclusion of Carbopol Aqua SF2 polymer (in any quantity, not even approaching 8%) is unncessarily complicating the issue.
Do you mean SLS or SLES? either way, what is the concentration?
1% fragrance in a body wash is a high level and it may be that the surfactant combination is unable to tolerate that amount of some perfumes and remain clear
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Oh!
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Possibly. I think it depends on the other components in the system.
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Water at pH 5 is not water but an acid. EDTANa2 is a salt. Adding this to an acid will form EDTA free acid or the monosodium EDTA salt. Both of these have a limited solubility in water - the free acid being effectively insoluble.
A formulated product would normally be a complicated mixture of numerous components and crystal formation may well not occur in the presence of these, whatever the pH.
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It is rather late in the progression of this saga to be asking which emulsifier should be used. That ought have been one of the priorities when you first began thinking about the product.
I can’t really give any recommendations about a choice of emulsifier as I don’t know enough about your aims or about what is available to you. Also, I would not have produced a formulation like the one you are querying so it is “out of my comfort zone”.
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Your inability to afford to hire a chemist does not mean that anyone here can offer their services for free. Have you consulted manufacturers literature, textbooks, online cosmetics learning courses?
The owner of this site offers courses in learning cosmetics formulation (see right hand side of the page)
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You seem to be ignoring the absence of an emulsifier.
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Prior to
jolie contributing to the thread, the last post here was January 2015. I think the query has been settled. -
You mentioned Polyacrylamide & C13-14 Isoparaffin & Laureth-7 earlier. This does not appear in your later postings.
As Bill points out, there is no emulsifier present. The Polyacrylamide & C13-14 Isoparaffin & Laureth-7 is not an effective emulsifier alone - even it is actually present. It is described by the manufacturer as “Sepigel 305 is a thickening, stabilizing, liquid, ready-to-use polymer.”
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A Gooooooogle search using the keywords “emulsion technology” will give a number of hits, not all necessarily agreeing with the views expressed here.
A simple step by step slide show (93 slides!) is given in https://www.slideshare.net/MarciaRebelo1/emulsion-technology and there are more in the R.H. panel.
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If the function of a cleanser is to remove dirt and fatty materials from the skin then adding a refatting agent to the product will reduce its efficiency.
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I agree about your spontaneous combustion thoughts, Kloe.
Charles Dickens wrote about the phenomenon and, thinking about the hygiene practices of people at that time and earlier, it could well be that accumulated sebum produced by the body and absorbed into clothing or the large amounts of goose grease that was applied to bodies to “keep out the cold” - neither of these materials being removed with any enthusiasm - could well have acted as wicks to encourage burning from a stray spark, ember or flame. -
then a MacDonald’s burger?! And we eat those all the time.
I don’t. Never have.
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I am completely retired from work myself. I wanted to clarify with you for others who may be interested.
Please be aware of other comments made in regard to ingredients and their provenance, though.
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I don’t understand. If you require to replace PEGs why are you happy with polysorbate 20?
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You are asking the impossible. Adding viscosifiers or non-volatiles to a solution will delay evaporation, not increase it.
The only way to increase evaporation rate is to use a more volatile solvent.