On the web, there are tantalizing references to to Japanese laudry starches which contain PVA (vinyl alcohol -- not polyvinyl acetate) as an additive to bubble mixes. Some indicate (with pictures) that it improves bubble color and others report that it improves the strength of the skin.
I have been in touch with several people that have explored PVA on its own as an additive and none found it worthwhile enough to pursue (some said it actually ruined their mixes). The one person that had good results was using Japanese Laundry starch rather than straight PVA. After an evening reading articles in scientific journals about laundry starch, it began to be clear that in laundry starch, the PVA works together with the modified rice starch. It occurs to me that it is the combination of (modified) rice starch and PVA working together that has the beneficial effect on bubbles. Unfortunately, it seems impossible (so far) to find it in the U.S. I have been to quite a few Japanese language supermarkets without finding it. One source says that not all PVA-containing Japanese laundry starches work as some contain anti-foaming agents. Furthermore, the bottles indicate 8% PVA but no mention of starch or water.
I received a message from a reliable source who said this when asked about PVA-containing starches
- I've used it many times in the form of laundry starch from Japan. To me it contributes to the longevity of a bubble. Not by acting as a humectant; but by actually stengthening the bubble skin itself. Combined with elastisizers such as j-lube or HEC etc., it seems that the "Japanese Laundry starch w/PVA" strengthens (not enhances) that elasticity as well. I also feel that the PVA in the laundry starch actually acted as a binder of sorts (linking agent?) creating a more homogenous and stable mix of the various additves combined. Ingredients that didn't go well together seemed to do so when the pva was added. I could clearly see the characteristics of both ingredients in a stable strong bubble juice. That's something else I need to get more of when someone flies over from Japan..I got just a little over a bottle left. I'll be glad to get some to you when that time comes.
Here is an interesting post on SBF.
If anyone has information about where to find this starch in the USA or knows anything about its contents or use, please post the information here.
Here are some pictures of bottles of Japanese laundry starches known to be beneficial to bubbles:
The following patent mentions PVA. The amount they mention seems VERY high (25%) which makes me wonder if they mean a PVA solution (PVA is generally sold as a powder).
Dr. Aristid Grosse mentions here that bubble solution can be made from polyvinyl alcohol, glycerine and water. No proportions are given. He further mentions that when added to a particular type of soap bubble solution that the resulting bubbles can last for years.
David Katz mentions PVA in his online books Chemistry in the Toy Store and Soap Bubbles (parts 1 through 4). In Soap Bubbles, Katz creates a 4% (by weight) PVA solution and makes a bubble mix by making a bubble solution that is PVA solution and 2% Ultra Joy detergent. This created longer lasting bubbles than using larger amounts of detergent.
Burst Resistant Bubbles. Interesting patent application that includes a number of formulas for bubble solutions.
Invert Sugar Bubbles. Another patent application that mentions PVA.