Home Cosmetic Science Talk Formulating Color and makeup Pigment particle size

  • Pigment particle size

    Posted by Anonymous on July 1, 2016 at 1:22 am

    I wet and disperse pigments in Isododecane for my liquid to matte lip stain it’s perfect for the formula.  I also pre grind the pigments in a spice grinder 
    I got a glass muller still waiting for the flat slab. My question is how do I get the pigment particle size very fine so the previous Fails don’t happen . Plus when the pigments aren’t fine enough it seems perfect but starts to crumble or you can see little specs of it.

    Zolveria replied 8 years, 3 months ago 4 Members · 32 Replies
  • 32 Replies
  • Anonymous

    Guest
    July 1, 2016 at 1:40 am

    Do I need to wet with water first and disperse in Isododecane or is that wrong ? 

  • Anonymous

    Guest
    July 1, 2016 at 1:54 am

    Should I grind pigments dry first without a dispersing agent with the glass muller & slab?

  • Bobzchemist

    Member
    July 1, 2016 at 1:25 pm

    No, you want to dry grind the pigments first in the spice grinder. Ideally, you will use talc (if you can tolerate the opacity) or plain fine mica/sericite as a grinding aid, at a 1:1 ratio with your pigments.

    Don’t use water - just don’t. 

    Next, you want to make a mixture of your dispersant plus your oil. You can use isododecane if you absolutely have to, but a heavier/thicker oil will work better, and shouldn’t hurt your wear too much.  Heat this up if you have to melt the dispersant - I’m a big fan of Ganex WP 660 for this. Stir the pigment mixture into the hot oil/dispersant mix at a 60:40 ratio. Let it cool, then use the muller.

    Remember, you have to evaluate each dispersion while you’re making it and even afterwards. If it’s too dry/crumbly, add a little bit more oil and mull it again. 

  • Anonymous

    Guest
    July 1, 2016 at 11:43 pm

    This is the glass muller I got  & slab

  • Anonymous

    Guest
    July 1, 2016 at 11:44 pm

    Omg I am sooooo stupid look at the slab I got today !!!! :D

  • Anonymous

    Guest
    July 1, 2016 at 11:44 pm

  • Anonymous

    Guest
    July 1, 2016 at 11:46 pm

    Okay Thank you Bob I will do that now!!!! I haven’t gotten mica or talc yet can I still try this without the aid? 

  • Anonymous

    Guest
    July 2, 2016 at 4:47 am

    Can I mix Polyisbutene with the isododocane to make it thicker?

  • Anonymous

    Guest
    July 2, 2016 at 4:49 am

    What is ganex? And how should I heat it ? Sorry

  • Anonymous

    Guest
    July 2, 2016 at 4:53 am

    I have been purchasing from making cosmetics but they don’t carry ganex where could I purchase this for personal use

  • Anonymous

    Guest
    July 2, 2016 at 4:53 am

    I have glass beakers that are heat resistant should I use this on a mini stove?

  • Bobzchemist

    Member
    July 2, 2016 at 5:07 pm

    Ganex looks like a commercial-only ingredient, sorry.

    Try jojoba esters from FNWL http://www.fromnaturewithlove.com/soap/product.asp?product_id=OTHJOJOEST70US87 
    http://www.fromnaturewithlove.com/soap/product.asp?product_id=OTHJOJOEST44US87

    or cera bellina from lotioncrafter
    http://www.lotioncrafter.com/cera-bellina.html

    Glass beakers are good to use.

    A decent sized glass plate should weigh a lot. You will get a better price from a local shop than you can online.

  • belassi

    Member
    July 2, 2016 at 5:09 pm

    Why not use a polished granite slab, wouldn’t that be harder than glass? And less breakable?

  • Anonymous

    Guest
    July 2, 2016 at 11:42 pm

    Okay thank you ! I will try both 
    I don’t know where to get a pre cut granit slab though I don’t think they sell them cut not sure

  • belassi

    Member
    July 2, 2016 at 11:49 pm

    Places that do granite kitchen tops etc should be able to let you have an offcut of polished granite, I should think. But I really don’t know if it is better than glass.

  • Anonymous

    Guest
    July 3, 2016 at 1:19 am

    I tried these steps but my Liquid lip stain is flaking now . I put predispersed isododocane with octyldodecanol the pigment partly size dispersed in castor oil. 45-50% pure dye content. Very fine dispersion (free of aggregates > 5 microns). Viscous liquid, odorless. Water-insoluble, oil-dispersible.

    but it’s flakes like this I don’t know what to do now

  • Anonymous

    Guest
    July 3, 2016 at 1:29 am

    Here are the ingredients : 

    C9-C11 Isoparaffin, Trimethylsiloxysilicate, Dimethicone, Silica Dimethyl Silylate, Quaternium -18 Bentonite, Propylparaben. May Contain: MICA (CI77019), CI77891, CI 15850, CI45410, CI77492, CI 77499, CI 77491
    I know since the pre-dispersed in castor oil and anything that has oil in it will make the formula dry less matte that’s why I like the isododocane . The octyldodecanol didn’t work by itself either. 
  • MakingSkincare

    Member
    July 3, 2016 at 7:03 am

    You might want to use pre-dispersed, coated pigments/mica - try kobo and sensient, merck etc and use bentone, aerosil etc.

  • MakingSkincare

    Member
    July 3, 2016 at 7:23 am

     I can’t edit my comment above, but wanted to add to my list above: KF-7312K by Shin-Etsu

  • Anonymous

    Guest
    July 3, 2016 at 11:07 pm

    I can’t purchase from them since I am small scale sadly ): but thank you 

  • Anonymous

    Guest
    July 3, 2016 at 11:20 pm

    That’s why I have been struggling to do it myself but the making cosmetics said to just mix the isododocane with the predispersed iron oxide in the castor oil and I believe that’s why it’s flaking off so I guess I might either have to give up or try somehow to make the particle size smaller before I disperse them in isododocane …. 

  • Bobzchemist

    Member
    July 4, 2016 at 5:02 am

    It’s flaking off because the film is not flexible enough, and its adhesion to skin is not strong enough. The right plasticizer will fix both problems at once.

    This really has no relation to particle size.

    Belassi, we use ground/frosted/etched glass plates because the rough surface is needed to grab the pigment agglomerates long enough to increase shear, and also because they’re easy and inexpensive to replace when they wear smooth. Using a polished surface of any material won’t work to grind pigment at all.

    I suppose you could use a slab of granite, but it would have to have a surface similar to ground glass, and I don’t know how much it would cost, or how much it would cost to re-surface it after it wears out.

    We used to use a 10″x10″ or 12″x12″ piece of 1/2 inch or 3/4 inch thick etched plate glass, which lasted for about 6-8 months of daily use. Make sure to get beveled or rounded edges, straight-cut edges will be sharp enough to slice up your hands. 

  • Anonymous

    Guest
    July 4, 2016 at 7:18 am

    Okay I will look it up thank you. And where can I buy a  plasticizer. But the mortar and pestle does not disperse right? I noticed the isododocane sits at the top of the castor oil/ octyldodecanol dispersion this is what the glass Muller / frosted slab will help with? The also offered the advice of getting a homogenizer but if I have a glass muller already should that be enough? 

  • Anonymous

    Guest
    July 4, 2016 at 7:18 am

    *they

  • Anonymous

    Guest
    July 4, 2016 at 7:22 am

    Would a 10×10 x 3/16″. polished edge tempered glass work ?

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