Bobzchemist
Forum Replies Created
-
It’s a marketing gimmick - if we don’t have a sulfate on the ingredient label, it’s OK to claim sulfate-fee. There’s actually nothing wrong with sulfates anyway, so we’re not concerned about safety.
-
Need more details…
-
Hey, @Perry, you want to help out here on types/thickness of foams?
For humectants, I’d stick with glycerin. It’s cheap and it works. Why mess with that?Propylene Glycol, on the other hand, is used in most formulas as a carrier/solvent and sometimes a coupling agent. If you don’t need it, don’t put it in. (That statement should be carved over the door of every R&D lab) -
Why do you want to thicken lotions without using polymers? And does this mean that you are also excluding non-acrylic polymers? PEGs, for example? Are you excluding “natural” polymers also, like polysaccharides?
Polyquaternium 37 is also a polymer, you know…I will also point out that it is completely impossible to mimic the feel of a carbopol-containing lotion with anything non-polymeric - be prepared for a radical difference in skin feel. -
Suspension ability is a function of yield value/yield stress, not viscosity/thickness. It’s possible to formulate a relatively thin gel with good suspending capacity.
(http://www.lubrizol.com/Home-Care/Documents/Technical-Data-Sheets/TDS-244-Measurement-Understanding-Yield-Value-Personal-Care-Formulations.pdf )How this holds up for high-surfactant formulas isn’t something I’m familiar with. -
Perry posted a list a while back - try searching for it. Probably the easiest thing to do is to ask questions here.
-
If you substitute Suganate 160 (APG Sulfonate) from Colonial for your Decyl polyglucoside, it will thicken synergistically with CAPB and salt.
Also, glycerin is a foam suppressant - try using less. -
Boiling the water is the easiest/simplest way to make it sterile - the concept here is that a sterile product => sterile container + airtight seal does not need preservation. If you’re not going to boil, then you will have to sterilize your product, container and mixer another way. (It’s better to boil the water or product with a cover, and then allow it to cool while still covered for a bit before filling. If you are going to try filling while the liquid is still boiling hot, USE GLOVES!) (as usual, please don’t ask how I know this - I just do, ok?)
This is only practical for home or lab, btw. It’s too labor intensive and the components cost too much for it ever to be cost-effective for production. -
If PG irritates your scalp, you may have problems with many other chemicals as well. It’s not that I’m against preservatives, it’s just that you don’t seem to have the resources to test for skin irritation properly.
Try aseptic packaging - these sterile transfer pipettes can be filled with hot liquid and then sealed with a candle flame to give you single-use packaging: -
Depends on how aggressively you are trying to exfoliate.
One option would be to use toothpaste-grade silicates: http://www.hubermaterials.com/products/silica-and-silicates/dental-silicas.aspx. It is at least debatable whether precipitated silicates are in amorphous or crystalline forms.
A more gentle option would be to form wax microcrystals in-situ, using something like polyethylene, for example.An intermediate option might be to use ground mica - but while mica platelets are clearly crystalline structures, you would need to decide yourself if grinding those crystals down to micron size made them “micro-crystals” -
When working at a small scale, you can skip the preservatives, and just keep the tonic refrigerated..
-
@martinkul, any of the powered sprayers I mentioned should work with just about any spray starch formulation.
You can use this one and take out the propellant, for example: -
@milliachemist, yes, I think the whiteness comes from re-emulsification. The products that do not have this happen are formulated so that they are not able to form w/o emulsions regardless of how little water is available.
-
I’m not sure I agree with that article. It may help to try to imagine what is going on when you rub an emulsion into your skin.
First, the emulsion mixes with everything else on the skin - water, salt, sebum, etc. Next, as you continue rubbing, two things are happening: 1) The water in the emulsion starts to evaporate, and some part of it is also taken up by the skin. 2) A great deal of shear force/stress is being applied to the emulsion -more than enough to re-emulsify the product. That’s what I think is happening - as the water level in the emulsion drops, the emulsion turns from an O/W emulsion to a W/O emulsion, and only then to an emollient film, as the water level drops further.I’d love to hear other people’s opinions on this. -
Making extracts is not something we typically do in “industrial” cosmetic chemistry. Generally speaking, we would go for option d) find someone who can make b or c for us.
You also have to recognize that the vast majority of cosmetic chemists work with the assumption that extracts do not actually do anything. In fact, if an extract actually produced some physiological effect on the skin, any product made with it would possibly, arguably, be a drug, not a cosmetic, and would be illegal to sell in the US without filing a NDA (New Drug Application) with the FDA. So, there is no need for a standardized extract, or a best practice in making them, since their only legal use is to provide a marketing claim. This is also why almost all extracts are used at levels of a tenth or hundredth of a percent.That being said, if there was an extract that we wanted to get a real effect from, we would still want it done by someone else. The reason for this is that, while making an extract isn’t that difficult, making a standardized liquid extract, even from a standardized powdered one, takes a level of analytical equipment and expertise that most of us don’t have access to. The problem is that we would have to prove, after the extract is made, that 1) it has a standard level of ingredient in it and 2) it is safe for use in our products and on our customer’s skin. Too much work for most cosmetic companies - we’d be more comfortable paying someone else to do this for us, and there are a number of suppliers who do nothing but that.On the other hand, making extracts is not that hard, and if you are making cosmetics at the level of a home crafter or a mini-business, it might pay to do it yourself. Information on making water or alcoholic extracts is readily available on the web. -
You are running into a force/power containment problem. There’s no way to keep a CO2 charge in a regular sprayer - it just leaks out.If you don’t want to just use the hand sprayer, you have three options:1) use a pump-pressurized sprayer or mister:2) Use a compressed air-powered sprayer with a separate can:3) use an electric sprayer
-
I will look into the importation problem from this end. Maybe we can find a better solution (pun intended). I suspect that there’d be a minimum order quantity, though, and it would be at least $100 US.
-
Yaay Rachel! Congratulations on your new job!
The best advice I can give you is to take lots and lots of notes. Most places don’t realize how overwhelming the volume of introductory information can be - plus, it makes you look studious and prepared, always a good thing. -
yes, but…it’s not healthy to expose humans, and particularly human eyes, to this light.
-
What is in your active phase, and what’s the formula for your base?
-
@Priya - we’re trying to keep things so that each discussion is separate. Since your question has nothing to do with the original question, please re-post this in a new discussion.
-
I need more info. What kind of dispenser will you be packaging the starch into?
-
Since that’s a Huber silica, their technical service department will help you with your formulation.
Also, this patent has a couple of formulations: http://www.google.sc/patents/EP1313439A4?cl=en -
which silica are you using?