johnb
Forum Replies Created
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I have become very cynical in my old age about the vast majority of “ingredients” that are included in cosmetic products.
That may be partially that I have more recently become involved with the formulation of topical small molecule pharmaceuticals where it is necessary to provide evidence (first to the company regulators then to the authorities) that any component of the product has a function. Stuffing a product with anything and everything that comes to hand, as some cosmetics seem to do, is just unacceptable.
So what convinces me an ingredient in a cosmetic provides a benefit is evidence. This may be science based or practical based - provided an effect can be demonstrated. In the case of panthenol, as has been said, it penetrates hair shaft-absorbs water and swells to provide body but this effect is very difficult to observe so I would not include it in a shampoo. On the other hand, panthenol has a demonstrable conditioning, moisturising and softening effect in leave-on (or is that leave-in
) skin care products - especially suitable for a baby’s bottom.I have particular difficulties all round with shampoo products which are claimed to provide numerous benefits. The function of a shampoo is, as far as I’m concerned, to clean the hair. At a stretch, I accept it might condition the hair as well. What I can’t get my head round is the (sometimes wild) claims that a shampoo has almost magical properties of treating any/all malfunctions of the scalp (e.g dandruff, seborrhoeic dermatitis). Shampoos are rinse-off and only in contact with the hair or scalp for a very short time after which almost all of any “active” ingredient is flushed down the drain and lost. Wouldn’t it be better to have shampoos return to their correct use and to have leave-on (leave-in
) scalp treatments as a separate product? OK, using a scalp treatment in addition to a shampoo and/or conditioner is extra effort but, if you are a sufferer of any disfiguring/discomforting scalp condition, you would be happy to put up with that and to know that some good may be being done and you haven’t poured most of the active material straight into the sewer. -
I first met with DME when DuPont introduced it as an aerosol propellant around 1980-82 under the name Dymel.
DuPont were investigating the suitability of DME as an aerosol propellant particularly for fragrance products. Our work was very positive showing the DME was far superior in almost all respects to LPG propellants which were then systematically becoming replacements for CFC materials.
DME was notably more expensive than LPGs but DuPont were assuring in that, with time, prices would become comparable. It seems, from what you say, Perry, this was not to be the case. -
I agree with Bill. Dimethyl ether is a good propellant material. I could never understand why it didn’t (or has’t) become more widely used.
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Compressed gas aerosols are unreliable and potentially dangerous.
The amount (mass) of gas that can be safely charged into a standard aerosol can is almost immeasurably small such that the slightest leak or inadvertant opening of the valve in an inverted position and easily result in rapid/very rapid discharge of the propellant gas.
Overcharging with gas can result in inflation/distortion of the can, violent release of the valve or explosion of the container - I’ve seen all of these happen.
There is a good reason why aerosol propellants are as they are.
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Vaginal products are outside the definition of a cosmetic.
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Careful, David, you’ll do yourself out of a job.
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A reasonably unbiased view:
http://www.cosmeticobs.com/ingredient-cosmetic/xylitylglucoside-anhydroxylitol-xylitol-1363 -
There are very good reasons that there are few, if any, natural shampoos on the market. They don’t work (saponin based) or are unpleasant to use (as you have found).
Why do you request a natural product when the one you have exemplified already contains a synthetic detergent (CAPB).
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There are natural detergents but they are either prohibitively expensive and/or unsuitable for this end use.
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The two mixtures outlined are so different in make up that a reasoned comparion is impossible.
If you want to make anything similar to your own formula you should at least use similar materials, as Dr Bob says, substituting sodium based surfactants for the ammonium based.
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Aquaxyl is a humectant and acts in a similar way to other humectant moisturisers such as glycerin, propylene glycol, urea etc and function by their hygroscopic nature holding water in solution and thus in contact with the skin surface.
Silicones like dimethicone act in a similar way to petrolatum that is by forming a water repellent occlusive layer on the skin surface thereby trapping water between it and the skin surface.
It should be borne in mind, though, that much of the occlusivity of silicones and petrolatum is lost when they are formulated into emulsion products in which the required contiguous water repellent layer is lost by the globular form in the emulsion and by the emulsifying agent itself - and potentially any other ingredients in the product - including humectants.
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You could try this grade available in small amounts:
It’s UK based. I don’t know if they send overseas.
There are some other UK suppliers.
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so is the purpose of having cetylstearyl alcohol to thicken/stabilize the emulsion like cetyl alcohol in cream?
Exactly so.
is it better to use Polawax with a low HLB emulsifier otherwise we need
to use alot of it in order to make a decent stable emulsion?Not necessarily. There are so many variables that a simple answer is not possible
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One of the shaving creams I formulated many years ago - which enjoyed a huge market share in Europe contained a small amount of Polyox (I don’t remember the grade) to give exceptional lubricity and slip for the razor and a superior skin feel after use.
http://www.dow.com/dowwolff/en/industrial_solutions/product/polyox.htm
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We still have very little information on the components of this mix.
It is thus impossible to give a meaningful reply.
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How about a betaine or amine oxide, pretty common in dish wash liquids. Omit the amide altogether.
Already suggested.
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Asbestos in talc was a problem many, many years ago but was resolved by the discovery of new sources, initially in Italy, that were asbestos free.
Lycopodium would not, I think, be acceptable as a cosmetic dusting powder. It is an unpleasant dirty yellow colour but, apart from that, it does not respond well to industrial mixing procedures. Lycopodium has a structure comprising an oil filled sac. in the rigours experienced during mixing etc, the sacs are easily ruptured, thus releasing the oil. This is accelerated and intensified by the presence of liquids (e.g perfume oil) and by solid particles (e,g talc). So, instead of a dusting powder, the result is a sticky mass.
All fragrance concentrates are liquids comprising blends of odourous materials. Adding “little bit of sparkle” will not alter this fact and have no effect on perfume stability. (Perhaps I have misunderstood this part).
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As I stated in my previous reply:
I cannot envisage any way that these materials are comparable. They are
chemically and physically totally different. The only property they
share is that they are both liquids - and that is only because Aquaxyl
is an aqueous solution.If you still believe that the two materials are comparable, there is nothing I can add.
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Cetylstearyl alcohol is NOT a high HLB emulsifier. I think you are confusing “required HLB” with HLB.
Required HLB means the HLB of an emulsifier that is suitable for that material in question (in this case cetylstearyl alcohol).
To answer your question “is that possible to create a good emulsifier system with high HLB emulsifiers instead of combination of low and high HLB?”
The answer is yes but a detailed response is so wide ranging, it is impossible to give a quick and easy answer.
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regipa, you need to begin a new thread to be able to get proper responses to your enquiry.
To begin, though, your main error in the formulation is that you are using soap as a base not a synthetic detergent.
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Change the quantity of Carbomer if the viscosity does not meet your requirements.
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Dermofeel Viscolid does not give transparent gels.
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I appreciate that CDEA is common in dishwash liquids. The amount you are using seems to me to be excessive for the amount of active detergent matter you have in your formulation - even your reduced amount of CDEA.
CDEA also varies in quality - some grades contain a large excess of free diethanolamine which can have a profound effect on the solubility in, and clarity of, the final product.
I have already suggested SLES as a partial or complete alternative. There are also betaine detergents and amine oxides and numerous others which could be useful.
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I would not use this material in a dishwash liquid. In fact, in view of the adverse health warnings there are about it, I wouldn’t use it in any product.
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I cannot envisage any way that these materials are comparable. They are chemically and physically totally different. The only property they share is that they are both liquids - and that is only because Aquaxyl is an aqueous solution.
The product you mention, Neutrogena Triple Age Repair SPF25, has the Aquaxyl very low in the LOI. It makes me class it in the category of fairy dust.