titanium dioxide not doing the trick

[luluzapcat]

I'm experimenting with rice bran oil, which I'd love to use as it's dirt cheap here and vegetarian, both qualities I value.

I love a bright white soap, and also want that as a base for adding color. But so far I've made three batches with most of my oils being RBO, and adding titanium dioxide doesn't seem to get anywhere closet to white.

First time I added TD to the soap after adding lye. I kept adding more without seeing the color brighten and gave up. Quantities uncertain...probably got up to 4x recommended.

Second time I added TD to the oils before adding lye, at recommended 1 tsp per pound oils.

Third time I dissolved the TD in water first and added that to the soap batter at light trace. That's one's still in the freezer (I don't like to gel) so maybe it will change when it cures...but it didn't lighten visibly like I see in videos.

 

[DeeAnna]

@Mobjack Bay says RBO adds a yellow cast to the color of the soap. I don't think you're ever going to get a bright white soap as long as you are using a lot of RBO as you say you're doing.

If you start with fats that are naturally white, you can add TD to intensify the white. But ya gotta start with white to begin with. If you use fats that are yellowish, no reasonable amount of TD will make that go away.

 

[BattleGnome]

Brambleberry used to have a line of lab colors formulated to contrast the greenish color of olive oil (not that anyone I’ve talked to ever had trouble with olive oil). The blurbs all talked about how they add a touch of... whatever to color theory it to average. I haven’t played with lab colors in years but it’s a place to start.

Are you only having trouble with white or have you tested any other color? I don’t know if color tricks will work with CP. like the way some people add a touch of blue to clear m&p to make it seem clearer (counteracts a yellow tinge from certain brands)

 

[cmzaha]

I never found I could get white soap with RBO which is why I do not use it much. I love HO Canola and Sunflower with a tallow/lard for white soap.

 

[Mobjack Bay]

I’m looking, but haven’t found a comparison table of pigment concentrations in different oils. In my limited research I learned that RBO has both chlorophyll and carotenoid pigments. From other papers I’ve read, I recall that some of the carotenoids are quite resistant to degradation. Olive oil has at least chlorophyll, which is much less stable as we’ve seen in the various green colorant experiments.

 

[Obsidian]

HO safflowe is another oil that makes a nice white soap if you have access to it. Its really cheap here so its what I use the most.

 

[luluzapcat]

Thank you all. I'm going to look more into some of the other potential cheap veggie oils.

Regarding other colors and also the carotenoid vs chlorophyll thing: I haven't tried other colors alone, and will have to do that. I DID try in my last batch to add indigo along with the TD. Looks like what I've got (a few days in) is green. Maybe the orange/yellow that I presume carotenoid is plus the indigo blue made green...

I REALLY appreciate all of your time, thoughtfulness in replying, and generosity with your knowledge. I've scoured this whole bulletin board so much...I feel like I'm talking to celebrities!