Article by: Kelly Dobos

As a cosmetic chemist you will undoubtedly be asked to make products that require you to combine materials that aren’t easily compatible.   Fortunately, there is a system that can help you get started.

Cosmetic Emulsions

Emulsions are one of the most common forms of cosmetic products. You find them in skin lotions, make-up, and even hair products. By definition an emulsion is a dispersion of two or more immiscible materials, where one phase, also know as the internal phase, is dispersed in the continuous or external phase. Cosmetic emulsions are classified as oil in water (O/W), water in oil (W/O) and water in silicone (W/Si). Multiple emulsions such as oil in water in oil (W/O/W) are also possible. Oil in water emulsions are the most common due to preferable cost and light skin feel.

In order to create an oil in water emulsion (one that remains stable for a long enough time), work must be done to overcome the interfacial tension between the two phases. This can be achieved by mixing; however mixing even at very high rates is not enough to provide long term stability.  An emulsifier or combination of emulsifiers is needed to stabilize droplets of the dispersed phase.  For example, simple oil in vinegar salad dressings will separate rapidly without the use of an emulsifier like mustard.

Using Surfactants

In this industry, we use surfactants to create emulsions. Surfactants are molecules that have a hydrophobic (oil soluble) and an effective hydrophilic (water soluble) portion. They act as emulsifiers by significantly lowering the interfacial tension and decreasing the coalescence of dispersed droplets.

HLB Formulating

Figuring out what surfactant to use for any specific formula will be a challenge you face as a cosmetic chemist. There is a great deal of research on surfactants and their behavior. But studying the thermodynamic equations and phase diagrams associated with surfactants can be a daunting task, not to mention the number of surfactants available to the formulator is vast. Luckily for us, William C. Griffin developed a way to streamline the selection of surfactants by utilizing the ratio of the hydrophobic to the hydrophilic portion of the molecule.  This method is referred to as the HLB (Hydrophile Lipophile Balance) method. Griffin first presented this method at meeting of the Chicago Chapter of the Society of Cosmetic Chemists in 1949 and it is still widely used today. He published the method shortly there after.1 (A bit of trivia for you, the Chicago Chapter was the first chapter formed in Society of Cosmetic Chemists)

The HLB method applies to nonionic (uncharged) surfactants but attempts have been made to broaden the concepts to other surfactant types including silicone surfactants. And using the HLB system to create emulsions is quite simple. All you have to do is calculate the HLB number of your surfactant, then the Required HLB for the oil phase and match the two numbers.

Determining the HLB of a surfactant

A typical nonionic emulsifier (e.g. Laureth-4) contains an ethylene oxide groups or polyhydric alcohol hydrophilic portions with a fatty alcohol hydrophobic portion. The HLB for a nonionic surfactant can be calculated as follows:

HLB = Weight % Hydrophile/5

Example 1: HLB calculation for Laureth-4

Molecular weight of ethoxylate portion = 176

Molecular weight of lauryl alcohol = 186

Wt. % Hydrophile = (176/(176+186)) x 100 = 48.6%

HLB = 48.6/5 = 9.7

Based on the calculation, surfactants with high HLB values will be more water soluble and those with low HLB values are more oil soluble. Division by 5 just allows for a compact, easy to use scale. The calculation is simple, but you won’t usually have to figure it out since most surfactant HLB values are readily available through literature references and surfactant suppliers.

Calculating HLB of oil phase

Each lipophilic ingredient in the oil phase has its own required HLB. These required HLB values are determined experimentally, however a method utilizing solubility parameters has been proposed by Vaughan and Rice.2 Required HLB values for some common oil phase ingredients are available to the formulator in literature. The Req’d HLB values are approximate and can vary by about ± 1 unit. It is also important to keep in mind that cosmetic emulsions often have complex oil phases with several components. The required HLB of an oil phase mixture can be calculated by first calculating the percent of the oil phase each ingredient contributes. This percentage is then multiplied by the required HLB for each of those ingredients and the results are summed.

Example 2: Calculation of required HLB for an oil phase mixture

The oil phase is 10% of the total formulation and consists of:

4% Shea butter, 40% of the oil phase. Req’d HLB of 8.

3% Jojoba oil, 30% of the oil phase. Req’d HLB of 6.5.

3% Sunflower seed oil, 30% of the oil phase. Req’d HLB of 7.

Total required HLB:

Shea butter contribution 0.4 x 8 = 3.20

Jojoba oil contribution 0.3 x 6.5 = 1.95

Sunflower oil contribution 0.3 x 7 = 2.10

Total Req’d HLB = 7.25

You can now select emulsifiers to match the required HLB of the oil phase and create an emulsion. A blend of high and low HLB surfactants is often used to achieve the desired value in part because of demonstrated effectiveness and efficiencies in packing at the interface. The HLB for the surfactant blend is calculated in same manner as the required HLB for a blend.

Example 3: Calculation of HLB for a surfactant mixture

The surfactant mixture is a 70/30 blend of Steareth-2 and Steareth-21.

Total HLB:

Steareth-2 contribution 0.7 x 4.9 = 3.43

Steareth-21 contribution 0.3x 15.5 = 4.65

Total HLB = 8.08

In order to match the HLB of a particular oil phase, it is easiest to set up a spreadsheet with the calculation and vary the percentages of each emulsifier in increments of 5% to find the right ratio.

Limitations of HLB

Although a very useful tool, the HLB system does have some limitations. For example additional water phase ingredients are not considered but still may impact the stability. The method also does not provide information as to how much surfactant is needed, but 2 to 4% surfactant is a good starting point to begin further optimization for stability. So it is important to keep in mind that the HLB system is not absolute in prediction of your formulations behavior, but a very good starting point for achieving emulsification.

References

1. Griffin WC; Calculation of HLB Values of Non-Ionic Surfactants, Journal of the Society of Cosmetic Chemists; 1954. Vol. 5, pp 249-235

2. Vaughan, C.D. Rice, Dennis A.; Predicting O/W Emulsion Stability by the “Required HLB Equation”; Journal of Dispersion Science and Technology; 1990. Vol. 11 (1), pp 83 — 91.

135 comments

  1. chris meyer

    so if I’m reading the link to the ICI packet right…I have an emulsion I’m trying to make which is a oil in water emulsion with 1% solid castor wax and 48% paraffin oil….I am to heat the oil and melt the wax into it…add an emulsifier blend(?) and then heat water to 15degrees over the melt pt of the wax and slowly add the hot water to the oil/wax/emulsifier blend under propeller mixing then after addition slowly start cooling and should get an o/w emulsion? everything I’ve tried has given me a w/o emulsion. Procedure lists sorbitan trioleate at <1% which is odd as its a low HLB emulsifier….no other emulsifier is listed???? omitted by mistake/purpose???

    1. chris meyer

      well they list starch at <1% but I figured that was just a thickener for the aqueous phase to prevent creaming….

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  3. majid

    hello there
    i need to crude oil in water emulsion. can you help me about suitable emulsifier for long time?
    email: majid.bhosseini@gmail.com
    thanks

  4. m.

    Hello there,
    Does anybody know the HLB value for mustard oil??? Can’t find it anywhere….
    Will appreciate a reply!

  5. Christine

    Hi there, was just wondering if anyone knows the HLB value for Sodium Cocoyl Isethionate? I have the Granules. Any info is appreciated, thanks.

    1. Kelly Dobos
      Kelly Dobos

      Christine
      I was unable to find a published value when searching, but you should be able to perform a calculation as noted or above or contact the supplier as they should have this information readily available.

  6. Asim Shaikh

    Hello

    Please email me how I can make silicon emulsion being used to make polish car dashboard
    The name silicone oil, viscosity and emulsifiers that can be used with the method of making me an email.

    best regard
    ASIM Shaikh

  7. Mike

    Hi there!
    I am very new to this and am wanting to make a saop spray for my plants. I use stearyl alcohol to emulsify my oil and soap base; and it works quite nicely. However that is the concentrate. When I add 1oz of concentrate to 1gal of water, I have to constatly shake as I’m spraying. Is there anything that would help me create a stable emulsion with these ratios of oil:water? Thank you so much for you any help that is able to be offered.

    1. Kelly Dobos
      Kelly Dobos

      Stearyl alcohol is not an emulsifier by itself… it can be a co-emulsifier and help provide structure in creams and lotions. You should consider selecting a combination of surfactants that match the HLB of your oil phase to emulsify.

      1. Mike

        I’ve got the oil and soap base emulsified with the stearyl. Where can I find a list of HLB. Like i use canola oil infused with rosemary and cayenne

  8. JOSE LUIS

    HI, COULD SOMEONE HELP ME DO Sodium laureth sulfate, TRANSPARENT LIQUID SOAP, HE USED lauryl alcohol 7 MOL HLB 12.3 sulfonated I HAVE BUT I CAN BE THE AROMA emulsify TURBIO ANY COMMENT THE GREETINGS agradesco.

    1. Perry Romanowski

      I’d suggest you post this question in our cosmetic science forum.

  9. john arthur (pharmacist)

    to create an emulsion the proportion is….oil water gum 4:2:1
    mix in a mortar with pestle..you get your emulsion simple. good luck

  10. Mark

    Hello everyone,

    I’m pretty new to this field and I need help. Now i understand how to calculate the HLB of oil phase and the required HLB of surfactants phase. One question though is what happens if the HLB of surfactants is much greater than required HLB of oil phase ? Is it still going to work? Or do they have to match the number to have stable emulsion?

    Thank you

    1. terry

      Hey there, I assume you haven’t gotten an answer, trying to help you here if I can. I have followed this person’s teaching’s for the last year or so, she’s very well known as a cosmetic chemist. Perhaps you’ve heard of Susan J. Barclay? her blog, Point Of Interest! is amazing, I almost guarantee you could likely find your answer there. She will even assist but have a flip through the myriad of posts. It’ll help, I’m sure. She’s all over Youtube as well.

      Good luck, sorry I can’t answer you directly, I’m swamped as it is.

    2. Francoios Bolduc

      The HLB of the emulsifying surfactant ”must” be very near the one you need. If it is too low or too high it will not work. But if you use two or three emulsifiers of different HLB, then you can do a mixture of them to have the right HLB you need within a range of HLB. Then you will have more tolerance of HLB deviations and better results.

  11. Michael Whyte

    How do you calculate the following quantities… seem to be stuck. Anybody have an idea?
    A 35% Polyoxyethylene (20) oleyl ether (HLB 20) and 65% Polyoxyethylene (2) cetyl ether (HLB 5) was found to be optimal for a particular emulsion system.
    What quantities of Sorbitan monoleate (HLB 4.3) and Polyoxyethylene sorbitan monopalmitate (HLB 15.6) should be used to stabilize this system.

    1. Matt

      The HLB of the POE 20 oleyl ether is actually about 15.6 and the HLB of the POE 2 cetyl ether is 5.6, so these are very close to the two alternate materials. I would suggest trying the same original ratio (35/65) and see how it does. Because the SMO is slightly lower than the POE 2 cetyl ether, you may have to shift this ratio slightly toward the POE SMP (40/60). HLB is not an exact science, though, so try a few blends and see what ratio gives the best particle size and stability.

  12. kylie88

    Hello, I want to formulate a coQ10 cream regarding my research studies. My ingredients include coQ10, olive oil, cetyl alcohol, glyceryl monosterate, tween 80, span 80, propylene glycol and water. May I ask how to calculate 3 emulsifiers? Can I just calculate the quantity required for emulsifers of span and tween only? For calculation of oil base, that’s mean just consider calculation for olive oil and cetyl alcohol only not included propylene glycol? Thank you so much =)

  13. Philip Haw

    when making oil-in-water emulsions using the HLB system the main idea is to lower the interfacial tension between the combined oil phase and the combined water phase. At the lowest interfacial tension it takes the least amount of mechanical energy to form the emulsion and it takes the least amount of surfactant to maintain emulsion stability. Using the general principles of the HLB system allows you to do a paper calculation of the theoretical required HLB of your unique oil phase in plain water and from that starting point you have the highest likelihood of success. I worked for Mr. Bill Griffin at ATLAS and ICI and for years taught the HLB system to our customers. I know from personal experience what a time saver applying the HLB system can be. For more information on HLB I suggest going to the CRODA website. The current CRODA company is the “keeper of the flame” on HLB and can provide you with a list of required HLB’s for most of the common cosmetic ingredients. HLB theory is also very successfully applied to the crop protection industry and to many industrial applications.

    1. robert

      vorrei fare un emulsione siliconica o/a latteo olio siliconico 350 cts che tipo di emulsionante va aggiunta?

  14. yaswanth

    while calculating HLB for oil phase, we can water/oil phase miscible components ????
    eg: Propylene glycol

  15. Madhur

    Hi All,
    I need emulsify following
    15 gm Palm Oil
    85 gm High Fructose Corn Syrup( corn syrup has 50% Solids and 50% water)
    is it possible if yes, what emulsifiers should i use
    regards,
    Madhur

  16. sajeesh

    Sir

    I am interested to form emusion of oil in water.The size of oilm droplets i am expecting is nearly 15 um.I have mineral oil and DI water and Tween 80 as the surfactant .Would you suggest me any method

  17. chirag

    Hello…
    If I want to stable emulsion of 20% toluene in remaining water using non ionic surfactant (combination or single)
    Then how can calculate reqired HLB for toluene (oil) from their structure without experiment for only prediction

  18. free download Romadoria hack

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  19. David

    Anybody got an idea of the required HLB of Ozokerite Wax?

  20. MIC

    Can anyone tell me the HLB value for Petroleum Jelly in a W/O emulsion

  21. Herb

    How does one use the HLB system with multiple emulsifiers? I often see formulations that have 4 emulsifiers: 2 low HLB and 2 high HLB numbers.
    sometimes 1 low HLB, 1 mid-range and 1 hi HLB?

  22. masume

    Hello

    Please email me how I can make silicon emulsion being used to make polish car dashboard
    The name silicone oil, viscosity and emulsifiers that can be used with the method of making me an email.

    best regard
    biglar

  23. Helen

    Dear Kelly,
    How can a mixture of petroleum jelly, mineral oil, castor oil and glycerine be emulsified

    1. Kelly Dobos
      Kelly Dobos

      Hi Helen,
      If you use the HLB method, you must perform the calculations above for your oil phase.

      1. Helen

        Dear Kelly,
        Thank you for the information on HLB method. Do you have a list of required HLB for cosmetic ingredients

        1. Kelly
          Kelly

          Sorry, I don’t have a list. But you should be able to easily find values for common ingredients on the web.

  24. maria

    dear kelly,

    is the calculation will be the same for multiple emulsion w/o/w. do i have to calculate for primary w/o first and then for secondary o/w later to get the desired HLB for multiple emulsion. or it has its own calculation?or i can just use surfactant with necessary value of HLB for both as there are no mixture of surfactant in both primary and secondary emulsion. thank you

    1. Kelly
      Kelly

      Hi Maria,
      Multiple emulsions can be a little more tricky. I don’t have much experience creating them but here is the title of an article which you should find helpful.

      Multiple W/O/W emulsions-Using the required HLB for emulsifier evaluation.
      Authors – Schmidts, T., Dobler, D., Guldan, A.C., Paulus, N., Runkel, F.,
      Journal – Colloids and Surfaces A: Physicochemical and Engineering Aspects

      1. maria

        thanks kelly for your reply. i really appreciate it. this article is very helpful for me as i’m now developing a formulation for multiple emulsion for my research studies. thanks again!

  25. sohail khan

    Dear,
    I have done several trial & error but finally couldn’t get clear/transparent emulsion.I donno where the problem is?Required HLB for oils & Hlb of my surfactant all is maintain somehow in my little knowledge.But still solution become milky/to cloudy.I am trying to mix some of my essential oil blend like(Tea-tree,thyme, eucalyptus,cardamom, cinnamon,spearmint)to purified water to get a clear solution without using any alcohol. But always my solution become milky even oil & water mixed properly.Could anyone suggest some way to come out form the error?

    1. aleem

      sohail u can increase your emulsifier and use a sonolator to reduce emulsion particle size so it become transparant.

  26. Armando

    Could you tell me how to calculate the required HLB for menthol and for peppermint and spearmint oils.

    Thanks,

    1. Kelly
      Kelly

      You can search for published values or determine experimentally. To determine experimentally you would prepare emulsions with surfactant blends from high to low HLB values and the one that is most stable would assigned as the required HLB.

  27. hasani

    dear kelly
    thanks for your guidance .i do that……
    any one can help to me?

  28. hasni

    dear kelly:
    can you answer to me?
    my problem is about making a stable emulsion w/o
    oil is vaseline and system HLBis about 7.35
    thanks for your guidance .

    1. Kelly
      Kelly

      hasni,
      You will have to determine determine the right emulsifier system experimentally.

  29. hasani

    i want to make a stable emulsion from water(that some salts are solved in it)and vaseline(petroleum jelly)
    which kind of emulsifier is suitable for it?i use of GMS but it was separated after some minute,however is it posible that after solidification of cream and remelting it i have a permanent emulsion?

  30. Kate

    So… if you calculate the required HLB of an Oil Phase and the result is around 3-8, the emulsion will be an w/o.
    And if you calculate the required HLB of an oil Phase and the resulst i 9 or above, the emulsion will be an o/w.

    Is this true???

  31. Rina

    What type of emulsifier can replace PGPR in emulsion that is added to the oil at 0.1%

    1. Perry

      That’s not enough information about the formula to give you a credible answer.

    2. Rina

      Water soluble material is disolved in 24% water. 10% PGPR is added to the oil phase. this emulsion at 0.1% will be added to the oil.

      1. Kelly
        Kelly

        Try alternate low HLB emulsifiers. You can find HLB values for a range of surfactants just by searching online.

  32. Wesley

    I have some questions to grit or small particulate that will go away upon a little rubbing in the final product. Would this be a for of flake that is a fall out in the emulsion or is this a solid particle film that could be forming in a formula?

    We are currently using polyglyceryl-3-diisostearate as well as glycerin.
    Oils: Mineral Oil, Cream Petro, Synthetic Beeswax which accounts for about 50% and then water is approximately 30%. Any help/insight would be greatly appreciated!

  33. Faiz

    Dear
    I want to make an emulsion of Menthol and eucalyptus oil in water. Please suggest me some solution.
    Thanks

  34. AK

    Hi

    I would like to make a sprayable sunflower oil emulsion. What emuslifier should I use and in what proportion? Thanks

  35. Chalie C

    Dear Kelly,
    Could you kindly help me in how to make a stable silicon emulsion and a stearic acid emulsion using a 2 stage homogenizer?
    Thanks in advance and congratulations for your article.
    Charlie C.

  36. scarroll

    How to get an o/w emulsion?
    If oil phase HLB required is 7.2, and you ad a high HLB emulsifier (15.5) and and low HLB emulsifier (4.4) in a ratio that is 7.2, what type of emulsion do you get? I thought unless HLB was > 10 (or there abouts) that you’d get a w/o

    1. Kelly Dobos
      Kelly Dobos

      You are correct, lower HLB surfactants (4-6) are W/O emulsifiers but other formulation factors like the size of the oil phase can effect formula type. You can simply test what type you have by trying to dilute the final product with water. A W/O does not dilute while a O/W would/

  37. Cindy

    I need to a sprayable oil-in-water. My oil, soy bean oil, has a HLB of 7. I have tried soy lecithin (HLB =7) and still had major separation. Any ideas on any other emulsifiers I can use?
    Thanks1

    1. Kelly
      Kelly

      Hi Cindy,
      Keep in mind that it best to use a high HLB and low HLB in combination to match the required HLB. Also the level of emulsifier may need to be inceased.

  38. Organic Herbs

    I find it so encouraging that I’m not the only human out there over the age of 20 who doesn’t know any of this!
    Time to learn *about all of it*.

  39. Alia sina

    Hi there, i have aproblem in mixing jojoba oil & glycerin using Tween 80 at 8% & span 8o at12 % the emulsion separate , did Iuse the right emulsifier or the % is wrong please repply & many thanks

    1. Kelly
      Kelly

      While it looks like your HLB is balanced, that’s quite a lot of emulsifier. Start with 2 to 4%. Also, is glycerin the only component of your external phase? If so the HLB method may not be a good predictor for stability.

  40. George p

    Hi all
    I want to ask if there is any negative effect of using too much emulsifier in a water in oil cream( except for paying more money)

    I mean can excess emulsifiers cause instability???

    One of my experiments has shown that using 3% of sorbitan sesquioleate is less stable than using 2% !!!!

    Can any one answer or guide me?

    Second, I want to ask about cooling phase, should it be done in very cold water bath and done quickly or it is better to cool the cream slowly !!!

    Please help me ?

    Thanks in advance

    George

  41. solomon

    Hi all,
    i want to create different conditions and substrates for biosurfactant production by a Bacillus subtilis strain. How do i determine the HLB value of the biosurfactants that will be produced?

    1. Kelly Dobos
      Kelly Dobos

      You would need to know the structure of your surfactant, and keep in mind, HLB applies to ethoxylated nonionic surfactants. I’m not familiar with biosurfactant structures, so I don’t know whether the HLB method applies.

    2. Dennis A

      You can make some VERY approximate estimates by observing solubility in water as follows:

      Dispersability HLB Range
      None in water 1-4
      Poor 3-6
      Milky w/ vigorous agitation 6-8
      Stable milky dispersion 8-10
      Translucent 10-13
      Clear solution 13+

      (copied without permission from ICI publication “The HLB System”)

        1. Phili Haw

          you can get the HLB talk from CRODA. Just go to their website. I am retired from CRODA and have given the talk many times.

  42. sajida

    i want to know which emulsifiers aresuitable to dissolve perraffin in silicone/water emulsion.as perraffin oils are non polar so kindly do guid me?

  43. phum

    Hello,George
    How can I make an easiest way to make an emulsifier?

    P.S.I want the answer fastest as you can.

    Phum

    1. Geo

      hey phum … would u please explain ur question more … sorry for that but i didn’t get the question to answer u !

  44. Abbasi

    Thanks so much.
    I want to ask one question:
    How i can prepare an EC of mineral oil(raw liquid parrafin oil)?I know some emulsifiers can use for it but with high using level(about 8%-10 %).I want to use a suitable emusifier with lower usage than it.
    regards
    Abbasi

  45. George

    hey all …

    I want to prepare the following formula:

    1- 40 g vaseline

    2- 40 g water

    3- 8 g emulsifier ( i shose Span 60″sorbitan monostearate, HLB = 4.7 and tween 60, hlb = 14.9): 7 g span 60 + 1 g tween 60)

    i heated to 70 for the oily phase and 73 for the water phase ..

    i mixed with a large stirring around 3000 RPM…

    the emulsion created is great .. but it lack the stability in 50 C

    CAN ANYONE OF U EXPLAIN !!! alghough i balanced the HLB !!

    1. Kelly Dobos
      Kelly Dobos

      Hi George,
      By the looks of it you are trying to create a w/o formulation. These are very tricky formulations to produce with only ethoxylated emulsifiers. Typically, waxes are added to the oil phase to help stbailize these types of emulsions and homogenization is a must. You may want to adjust your oil phase by adding oils with higher required HLBs and try making a o/w emulsion before attempting a w/o with this method.

      1. George

        hi Kelly .. .first i would like to thank u for this quick response

        i know that it is better to put some waxes… but i felt that the cream is thick enough due to the large amount of SPAN 60 WAX …
        still i don’t want to do O/W cream.. inversely, i’m insisting on W/O creams… if u can help me in this .. because till now none of my formulas was stable at 50 Centigrate for more than 48 hours …( the oily phase begine to separate !!!! )

        thanks a lot in advance kelly

        1. kelly
          kelly

          Hi George
          You are probably going to have to do some research on stabilizing these types of formulas and other ingredients you can use. Good luck with your formulation. -Kelly

    2. Philip Haw

      your stability failed at elevated temperature because of the melting point of the fatty portion of the emulsifier. At 50C the high HLB surfactant has a little shrinking of the EO chain (makes it a slightly lower HLB) and you have to remember that heat is energy and the surfactants start to want to “dance” away from their partners.
      The most simple fix is to add some cosmetic polymer to the water phase. Something like one of the carbomers from Lubrizol or Structure Solanace from AxoNobel (formerly National Starch). Another thing to remember is to continue stirring down through the set point. This means to stir down below 30C. The reason for this is if you have any crystalline material like fatty alcohol you want to make sure that it has a chance to start to re-crystalize and for the liquid gel networks around the dispersed droplets of the oil phase

  46. Clive

    My own view is that making successful emulsions is more of an art than a science. My first emulsion, looking back on it, was actually a butter: it contained 25% lipids, of which 15% was shea. It had a salmon colour because of the green tea extract in it. I thought it was a failure, but got demands to make more from test customers who really loved it. More lately I’ve been more into using desert plant bioactives.

  47. Saravanan

    How to test the stability of emulsion

    1. Perry

      Saravanan – see our blog post about stability testing.

  48. DP Mainali

    HLB value is a usefull tool but chances of product unsafety…

  49. muhammad

    i want understand but i cant ,some one tell me?

    1. Perry

      Muhammad,
      Your question is too vague to answer.

  50. Kelly
    Kelly

    1) Simple mixing with an impeller blade is all that is need to perform the testing.
    2) As mentioned above, there is no method for calculating the quantity of surfactants needed. You must determine the quantity experimentally.
    3) In general, you slowly add the expected internal phase to the expected external phase. I do not have a formal procedure to share.
    4) In general, the external phase should account for >= 26% of the total composition for traditional emulsions based on geometrical consideration of hexagonally packed spheres.

  51. BALASAHEB

    Dear kelly, I just want to know the process of how to make different w/o and o/w emulsions of organic solvents like toluene, hexane, benzene, cyclo hexane etc.. but my problem is that 1) how to set up apparatus for emulsions preparation?
    2) how to calculate required qty of surfactant ?
    3) what will be mode of addition of compounds ie water phase first or oil phase first….pls give me experimental procdure if possible. 4) I want some std qties for w/o and o/w emulsions of organic solvents as oil phase?
    expecting kind reply

  52. Kelly
    Kelly

    Dear Jagat,
    You must experimentally determine you required HLB as mentioned about by observing stability with the oil phase and various surfactant combinations to achieved different HLB values. We cannot help until you have done this.

  53. jagat jyoti sahu

    sir good morning
    i am taking 35% oil and formulating by taking tween 80 and span 80..i am geting the emulsification aftera week its geting separated . so kindly guide me to sucess my project

  54. jagat jyoti sahu

    sir good morning
    sir i have read your all suggestion,its very impressive. sir actually iam taking 40% essential oil and rest is water and excipient.so please guide me to formulate the cream. hope i wil get some detail idea.yours faithfully

  55. Perry

    @Jagat – I would suggest you post your question to the cosmetic science forum to see if someone there can answer it for you.

  56. jagat jyoti sahu

    sir please help me to my above question

    1. Perry

      @Jagat – thank you for your questions. Unfortunately, we do not have the protocol or information you seek.

  57. Kelly
    Kelly

    Hi Alicia,
    I would use glyceryl stearate, lecithin can have some draw backs with stability my opinion. 7% emulsifiers seems like a high starting point even for your large oil phase. I would place range of emulsifier levels on stability to determine an optimum level. -Kelly

  58. alicia

    So I’m thinking to do a blend of 40/60 stearic acid and glyceryl stearate:
    40% x HLB 15 = 6
    60% x HLB 4 = 2.4 = total 8.4 to match my recipe’s HLB requirement (total HLB of all the ingredients in my oil phase)

    I saw a rough ratio of 7:1 (oil phase: emulsifier) recommended somewhere in the archives here.. which would mean I require approx 7% total emulsifiers as my oil phase makes up 49% of the total formulation

    Would you please confirm am I on the right track with these calcs?

  59. alicia

    Thank you Kelly for your response, much appreciated!
    I am using stearic acid and/ or stearyl alcohol for the high HLB component. From a formulator’s point of view would you recommend glyceryl stearate OR hydrogenated lecithin for the lower value surfactant?
    trying to go “nature-identical” as much as possible with the products..but saying that would very much like to get the texture beautiful and stable!

  60. Kelly
    Kelly

    Hi Alicia,
    You are correct, you would need a combination of low and high HLB surfactants to emulsify using the HLB system. Or you can try creating soap based emulsion by neutralizing the stearic acid with a base like triethanolamine. -Kelly

  61. alicia

    I’m just learning about the HLB system and have been trying to perfect the texture of a cream. It has equal proportion of water to oil, has a little grittiness and just a small amount of water separating out. Have done all calculations and come to a total required HLB of 8.36…
    And now to select the emulsification system. Would you mind clarifying how I would achieve this with using what I have access to: Stearic acid and stearyl alcohol, both with HLB around 15? Do I need to combine with a low HLB value emulsifier like lecithin (4)? Thanks for your advice!

  62. jagat jyoti sahu

    sir would you like to give me the protocol if u have , how to proceed further for the determination of hlb of some essential oils. if u have some research article then plz send me some of them so that i can proceed further with u r guidance.
    regards jagat jyoti sahu
    waiting for u r reply

  63. Kelly
    Kelly

    Jagat,
    You would run accelerated stability testing with varying levels of emulsifier while holding the oil phase the same.

  64. jagat jyoti sahu

    how we can determine it by experimentally

  65. jagat jyoti sahu

    what is the protocol to determine the level of emulsifier

  66. Kelly
    Kelly

    Jagat,
    As noted above, the appropriate level of emulsifier will be determined experimentally.

  67. jagat jyoti sahu

    ok but i want to know the percentage of emulsifier to be used

  68. Kelly
    Kelly

    Hello Jagat,
    You will need to experimentally determine the required HLB for your oil. You create emulsions with a combination of high and low HLB emulsifier at varied ratios but the same total concentration to test different HLBs. The required HLB is then taken from the emulsion that remains most stable.

    1. Carol JK

      Hi Kelly, yes, i understand what you meant.

      Just wonder how to interpret/decide which emulsion remains the most stable? I have set the surfactant to be 3% (parenteral formulation).

      Then, all the resulting emulsion seems to be the same. Separation of oil and water has taken place. The oil will immediately float back to above after i shaken the emulsion (although the oil did dispersed into the water when i shaked the emulsion at 1st). However, i do see droplets of oil. They do not aggregate to form a bigger droplets. Should i just proceed with other surfactant? Because the same situation has taken place for the 3rd kind of surfactant’s mixture. Thanks for the advice. =)

  69. jagat jyoti sahu

    i want to know how to calculate the hlb value of cetronella oil.but first point is selection of surfactant.but how we wil select surfactant. we have oil percentage around 83 and water the rest. so kindly tel me on what basis i wil select the surfactant blend

  70. Kelly
    Kelly

    Hi Nancy,
    There are no rules on how much emulsifier you need , a good starting point is 2%. Placing various levels on accelerated stability testing can help you to select the optimum level for a particular oil phase.

  71. nancy

    Hi again Kelly, and thank you one more time 🙂

    Just like you said i couldent find many.
    Id like to aske you if there is any rules in how much emulusifer i should use.

    Thanks again!
    Nancy

  72. Kelly
    Kelly

    Hi Nancy,
    There aren’t many published values for W/O required HLBs, this maybe due to the reason that most cosmetic formulators favor O/W due to cost, ease of stabilization, etc. You may be able to find some if you search for a specific oil and it’s required HLB in W/O systems. Hope this helps!

  73. nancy

    Thank you for your answer.I do not know what Bancroft rule is but i will look it up.I wonder if you know a site with the HLB value of o/w and w/o emulsions.

  74. Kelly
    Kelly

    Hi Nancy,
    That’s a great question! The HLB for oils in O/W vs. W/O is different. Low HLB emulsifiers are used to create W/O formulations, and following the Bancroft Rule the phase in while the emulsifier is most soluble constitutes the continuous phase. So is the emulsifier HLB is low, it would be matched to an oil phase with a low required HLB. For example in O/W mineral has a required HLB around 10 and for W/O it is closer to 5.

  75. nancy

    hello i am making a project about HLB and i would like to know the hlb value of oils is the same for o/w and w/o emulsions..

  76. Kelly
    Kelly

    Hello Jagat,
    You need a required HLB for oils. Required HLB is not calculated but determined experimentally by using a range of emulsifiers with differing HLB values.

  77. jagat jyoti sahu

    please tel me how to calculate the hlb value of volatile oil like geranium oil .

  78. Usman

    Please guide us , We want to make silicone emulsion shinning polish

  79. Anup

    for vegetable base oil phase which PEG free emulsifier is best
    percentage is about 35 to 40.

  80. Kelly
    Kelly

    Bill,
    The HLB system is still a great tool for the formulator and one the I use frequently. The beauty is in the ease with which it can be used. As a big enthusiast of cosmetic science, it’s an honor to hear from you! Thanks so much, Kelly

  81. Kelly
    Kelly

    Glyceryl stearate SE contains a small amount of a monovalent soap such as potassium or sodium stearate.

  82. shivraj

    What is the defferrence between glyceryl monosterate
    and glyceryl monostearate self emulsifyig

  83. shivraj

    I want to make water in oil formulation
    how can we calculate the HLB for w/o

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  85. Bill Griffin

    Kelly Dobos,

    Dennis’ comments are a bit amusing in one sense of the word because slide rules were still in use then. Yes, we recognized some of the faults of the system and these were outlined in my thesis for a Master’s Degree in 1955 which, of course, was not published.

    It was my unimaginable pleasure to wander through a current emulsion innovation lab at the Croda plant a year or so ago and the advances on all sides was amazing beyond belief. Of course, the truly amazing thing is that the basic premise is still being used and taught so long after its development. Doubly impressive since my retirement happened thirty-one years ago.

    Cheers, and may you have as much fun as has been my good fortune in life – and without scads of money.

    Bill (HLB) Griffin

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  88. Dennis

    I know what I’m going to say here is provocative and sacrilegious, but this whole system seems somewhat antiquated and akin to the slide rule. I think modern formulation requires more flexibility and has available to it more effective tools. Using DOE and polymeric emulsifiers we can create better products faster and discover more unexpected combinations than using these HLB calculations, which don’t account for formula aesthetics or product perception. Even using this system it’s still an iterative process to achieve the look and feel of the product you want.

    1. Perry

      Certainly, you make an excellent point. There are more rigorous ways of making an emulsion. But this kind of background information is still useful in concept and the method (while antiquated) can still be used effectively.

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