If you've ever used a Lush bubble bar, you'll know they have a certain desirable consistency to them: they're firm, but crumble easily under the water for easy bubble-making action. They also aren't moist or greasy. Unfortunately, many of the duplicate recipes are.
Strangely, many of the duplicates seem to not even bother with a similar ingredient list to the Lush products. To me, the best way to duplicate a product is find out what's in the product you actually like. Granted you have do to a whole lot of "guesstimating" to figure out ratios, but after some trial and error you should be able to get it right if you're decent at formulation.
After much trial and error with publicly available bubble bar recipes, comparison to the "ideal" bubble bars from Lush, and addition of a few other ingredients to boost the bubble power, I've finally come up with what I believe is the perfect bubble bar recipe.
I've kept this recipe close hold for quite a while now, knowing that I had something pretty special. I'm still a little wary about sharing, but hoping that by posting my basic recipe here I will inspire the sharing of other great recipes from other formulators.
The below recipe is owned by Elemental Bath Company. Any links or sharing of this recipe must give credit back to my company. On that note, I hope you enjoy it! Please drop me a line and let me know how it turned out for you!
Bubble Bar (Solid Bubble Bath) Recipe
Copyright Alison Jordan, Elemental Bath Co. 2006
Be sure to read the entire recipe and instructions before starting this so you know exactly what you'll need and the expectations. The beauty of this recipe is the simplicity and versatility. For example, some people may not want to use SLS. So don't... go ahead and sub out for one of the other listed coconut-derived surfactants. Chances are that you won't even know the difference!
1 cup Sodium Bicarbonate
1 cup Tartatic Acid
2/3 cup Sodium Lauryl Sulfoacetate (SLSA)
3 tbs Cocamidopropyl Betaine
3 tbs Cocamide DEA
2 tbs Sodium Laureth Sulfate (SLS)
Fragrance Oil (to preference)
4-5 drops Liquid bath-safe coloring (Labomb works well)
Be sure to wear a breathing/respirator mask at least until all ingredients are fully mixed. Some of the powders are very fine (poofy) and can irritate your eyes, lungs, and sinuses. Always use rubber gloves and sanitized equipment.
Combine all dry ingredients into a large bowl. Mix well with a whisk and be sure to crush any lumps in the powders. When all dry ingredients are thoroughly mixed, slowly drizzle all of the wet ingredients into the powder mixture.
At this point, you need to work relatively quickly. Mix and kneed the mixture very well to ensure proper blending. The mixture will start out very sticky, but as it blends it will start sticking more to itself instead of your gloves :-)
Once the coloring is distributed throughout and your mix is a solid color (and no longer sticky, as noted above), it is ready to be molded. You can either push the mixture into the mold of your choice, or roll it into a log (to be sliced). If you wait too long to mold or shape it, the mixture may be too crumbly. In a pinch, you can add a bit more liquid (and of the wet surfactants will do). Try not to do this unless you have to in order to save the batch.
If you decide to roll it into a log for cutting, be sure to cut it into slices soon after to avoid crumbling. Decoration is optional, but these look great cut into single-use chunks with small candies embedded in the top. Use sugar-based sprinkles that will disintegrate in the tub, or something that can easily be removed before the bath- like small charms or buttons.
Set your finished bubble bars on wax aper to dry. It typically takes a few hours to dry completely and then they're ready to be wrapped or used.
Take your bubble bar (1-2 oz chunk or so, depending on the size of your tub and desired bubble volume) and crumble under warm running water. The better water pressure you have, the more bubble generated. If you have poor water pressure, do some serious swishing around the bottom of the tub with your hands while the water is still running to help the bubbles along. Sit back, relax, and enjoy your bubble bath. You deserve it!