Forum Replies Created

Page 35 of 59
  • Bill_Toge

    Professional Chemist / Formulator
    March 19, 2017 at 8:21 pm in reply to: What preservative to use for my formula ?

    @Danedane that depends largely on what else is in your product, and how sterile the clay is

    also, when I said it didn’t perform adequately, what I meant was that it worked, but the reductions in microbial counts during the challenge test weren’t fast enough for it to pass - an additional preservative was needed

  • Bill_Toge

    Professional Chemist / Formulator
    March 19, 2017 at 7:33 pm in reply to: small lumps forming in conditioner when NaOH added - help!

    do you add the caustic soda as a powder, or as a solution?

    try it both ways and see if it makes any difference

  • Bill_Toge

    Professional Chemist / Formulator
    March 19, 2017 at 7:18 pm in reply to: Skin creams linked to fire deaths

    @Perry strictly speaking, a hydrocarbon is a compound which contains only hydrogen and carbon

  • Bill_Toge

    Professional Chemist / Formulator
    March 19, 2017 at 4:00 pm in reply to: Organic Vegan Cosmetic Line in the UK

    unfortunately, due to the nature of these products, it impossible to create a product like this which is both all natural and performs to the required standard; one reason, and this is by no means the only one, is that cosmetic pigments are all to some extent artificial

    it’s a bit like trying to built a house that’s by the sea but also located near Leicester city centre - you can have one or the other, but not both

  • Bill_Toge

    Professional Chemist / Formulator
    March 18, 2017 at 10:55 am in reply to: Long-lasting aroma in cosmetics

    what’s the pH?

    if it’s much above 5.5, your preservatives will be ineffective

  • Bill_Toge

    Professional Chemist / Formulator
    March 17, 2017 at 7:08 pm in reply to: O/W (?) liquid foundation

    @JulietK Lameform TGI  can be used as an O/W co-emulsifier, but only in combination with another, high HLB emulsifier, and there isn’t one listed here; and it is not physically possible to create an O/W emulsion with the listed ingredients

    you’re right in that electrolytes are usually used to stabilise the water phase in W/O, but they are not compulsory, and given that there are no other stabilisers listed (long-chain polymeric emulsifiers, or oil-phase rheology modifiers) my hunch is that it’s been manufactured using an Ultra Turrax or a similar very high shear mixer, and the emulsion is stable by virtue of having a very small droplet size

  • Bill_Toge

    Professional Chemist / Formulator
    March 17, 2017 at 6:22 pm in reply to: O/W (?) liquid foundation

    personally I’d lean towards W/O, based on the fact that polyglyceryl-3 diisostearate is a W/O emulsifier, it’s high up in the list, and the only potential O/W emulsifier listed (polysorbate 20) is a) ineffective; and b) very likely not present in a substantial enough quantity to affect the product as a whole

  • Bill_Toge

    Professional Chemist / Formulator
    March 17, 2017 at 2:11 pm in reply to: Is Caprylic Capric Triglycerides not compatible with iso propyl myristate?

    @Shubh123 the HLB value you’ve quoted for caprylic/capric triglycerides is for a W/O emulsion - the figure for O/W is closer to 12

  • Bill_Toge

    Professional Chemist / Formulator
    March 16, 2017 at 3:53 pm in reply to: How to make exfoliating pH 3.5 resveratrol moisturizer more moisturizing

    @DRBOB@VERDIENT.BIZ probably not on its own, but the fact there’s a large amount of acid and electrolyte is very likely to prevent growth

  • Bill_Toge

    Professional Chemist / Formulator
    March 16, 2017 at 7:55 am in reply to: Kojic acid dipalmitate

    that depends on whether you have something to heat it with

  • Bill_Toge

    Professional Chemist / Formulator
    March 15, 2017 at 12:16 pm in reply to: Hlb of hydrogenated castor oil

    as castor wax is not surface-active, I assume you mean the required HLB value

    personally I’d assume it has the same required HLB as castor oil, as the only chemical difference is that hydrogenated castor oil has no double bonds, and that change doesn’t affect the overall polarity of the molecule 

  • Bill_Toge

    Professional Chemist / Formulator
    March 14, 2017 at 4:48 pm in reply to: Proper stirrer for shampoo making 50-100 litres

    another good configuration is with the shaft at an angle to the surface, so the vortex is relatively small, and generally not coaxial with the shaft

  • Bill_Toge

    Professional Chemist / Formulator
    March 14, 2017 at 7:59 am in reply to: Propanediol Deodorant

    @Belassi the sodium stearate acts as a gelling agent, and makes the product solidify 

  • Bill_Toge

    Professional Chemist / Formulator
    March 14, 2017 at 7:55 am in reply to: Idea can applied ?

    that depends: do you know about mathematical modelling of dynamic chemical equilibrium, and a programming language of some kind?

    if the answer to both of these questions is ‘yes’, then you can

  • Bill_Toge

    Professional Chemist / Formulator
    March 13, 2017 at 9:27 pm in reply to: Lip balm stick cracking.

    personally, I’d be tempted to remove the cocoa butter - that’s notorious for crystallising in the cooldown phase, and causing products to become grainy / crumbly / otherwise unsatisfactory if it’s cooled too slowly

  • Bill_Toge

    Professional Chemist / Formulator
    March 9, 2017 at 3:16 pm in reply to: aggregation when adding cetearyl alcohol

    there is no logical reason why using cetyl (C16) alcohol instead of cetearyl (C16/C18) alcohol would change the product’s ability to form an emulsion - or even why the emulsion failed to form in the first instance

    to my mind, this suggests one or both of the following:

    1. the emulsion cannot be consistently formed using this particular combination of method and materials

    2. the ‘cetearyl alcohol’ you used before is actually a different material

  • Bill_Toge

    Professional Chemist / Formulator
    March 7, 2017 at 10:16 am in reply to: The first formula I ever made was………

    the first batch I ever manufactured myself was 8 kg of Marks & Spencer peach foam bath, as part of a cost-of-product reduction exercise: they’d cut back the fragrance and surfactant levels slightly, and needed samples to make sure it was still acceptable to the consumer

    after that I made the five other variants in the range; after I started using a new lot of SLES halfway through the run I learned first-hand just how variable surfactant-based products can be in terms of pH and viscosity, even when all the materials are weighed out with rigorous accuracy

  • Bill_Toge

    Professional Chemist / Formulator
    March 6, 2017 at 12:01 am in reply to: When is pH not relevant

    because pH meters are electrochemical devices, the relevance and reproducibility of any readings depends on the conductivity of the product, which in turn depends on its composition

    as the conductivity decreases (whether this is due to a lack of ionic salts, or the presence of non-conductive co-solvents), the measured pH readings will become less accurate, less consistent and less meaningful overall

    in anhydrous products and W/O emulsions, the continuous phase generally has little to no electrical conductivity, so any readings are essentially meaningless

  • Bill_Toge

    Professional Chemist / Formulator
    March 5, 2017 at 11:48 pm in reply to: Would borax and cera bellina work as an emulsifier?

    @johnb I fully agree with you: the purpose of my post was to provide additional information about why the major branders did what they did

    @David given that a number of national authorities within the EU have impounded products containing perborates, and barred them from sale on the grounds that perborate and borate salts are category 1 reprotoxins (see RAPEX reports for details), I’d personally err on the side of caution and steer well clear of them

  • Bill_Toge

    Professional Chemist / Formulator
    March 3, 2017 at 8:09 am in reply to: W/O cream , loses viscosity

    agree with @Bobzchemist - I’d suggest adding a polymeric emulsifier, e.g. PEG-30 dipolyhydroxystearate

    also, the relative ratio of the two phases is irrelevant - the nature of the emulsifiers, and that factor alone, determines the nature of the emulsion

  • Bill_Toge

    Professional Chemist / Formulator
    March 2, 2017 at 3:08 pm in reply to: Lipstick Formula - What am I missing?

    personally I’d leave glycerine out; it’s not very miscible with oils, and it’s probably the root cause of your problem

  • Bill_Toge

    Professional Chemist / Formulator
    March 1, 2017 at 10:29 am in reply to: Would borax and cera bellina work as an emulsifier?

    @johnb the concern is very real, and arose from its classification under the Globally Harmonised System of chemical classification (which was passed into European law in 2008)

    because of this, it’s been classified as a Substance of Very High Concern under REACh regulations, which means there is a legal requirement for its usage to be tightly monitored, and for its usage in place of less contentious alternatives to be justified 

    in thise case, the branders clearly felt the case for continued use wasn’t strong enough, and it was simpler to use an alternative material that did the same job

  • Bill_Toge

    Professional Chemist / Formulator
    February 27, 2017 at 8:39 pm in reply to: Pomade emulsion watery on breakdown

    how are you manufacturing this product?

    forming emulsions requires a certain technique, or else it can go disastrously wrong

  • Bill_Toge

    Professional Chemist / Formulator
    February 27, 2017 at 8:18 pm in reply to: Would borax and cera bellina work as an emulsifier?

    borax is a category 1B reprotoxin, personally I’d avoid it altogether

  • Bill_Toge

    Professional Chemist / Formulator
    February 27, 2017 at 11:55 am in reply to: What is the smallest surfactant molecule?

    @jeremien I’d disagree - there are a few situations in which the shape, and hence the size, of the surfactant/emulsifier plays an important part in determining the overall properties of the system

    one example is the difference between using stearyl alcohol ethoxylates and oleyl alcohol ethoxylates as emulsifiers

    the two are almost identical in terms of chemistry and HLB, but you get very different emulsions because the latter is wedge-shaped rather than linear, and takes up more space at the interface than the former

Page 35 of 59