Zubbles is a commercial name for colored

soap bubble A soap bubble is an extremely thin film of soap or detergent and water enclosing air that forms a hollow sphere with an iridescent surface. Soap bubbles usually last for only a few seconds before bursting, either on their own or on contact wi ...

s. Zubbles claim to fame is that they are the first colored soap bubbles that do not leave stains. Instead they fade away with exposure to air, pressure, and water. ''

Popular Science ''Popular Science'' (also known as ''PopSci'') is an American digital magazine carrying popular science content, which refers to articles for the general reader on science and technology subjects. ''Popular Science'' has won over 58 awards, incl ...

'' named Zubbles the "Innovation of the Year" for 2005. ''

Reader's Digest ''Reader's Digest'' is an American general-interest family magazine, published ten times a year. Formerly based in Chappaqua, New York, it is now headquartered in midtown Manhattan. The magazine was founded in 1922 by DeWitt Wallace and his wi ...

'' agreed, saying they were one of the "Best Innovations" of the year in 2006.

Development

Zubbles were invented by Tim Kehoe, a toy creator from

St. Paul, Minnesota Saint Paul (abbreviated St. Paul) is the capital of the U.S. state of Minnesota and the county seat of Ramsey County. Situated on high bluffs overlooking a bend in the Mississippi River, Saint Paul is a regional business hub and the center o ...

. After an unexplained breakthrough in his kitchen, he was able to produce blue bubbles, that, unsuitably for a toy, stained clothing. After an eight-year-long delay in developing the idea further, he recommenced his investigations after forming a new toy company. In the process of trying to rediscover the recipe, he changed the formula, making the coloring water-soluble. However, having to wash off the color from the bubbles rendered them unsuited to a mass-market toy. Kehoe hired the dye chemist Ram Sabnis, who arrived at a formula where the color would disappear on its own, with sufficient exposure to air, and without washing or staining. The company entered into a global license agreement with Spin Master Ltd. for Zubbles Colored Bubbles in December 2005. Despite announcements of expected release dates, Spin Master dropped plans for commercial production due to complexities in the manufacturing process. In 2008, the company reached a licensing agreement with a new toy company called Jamm Company. Zubbles commenced commercial sales in June 2009. In 2011,

Crayola Crayola LLC, formerly the Binney & Smith Company, is an American manufacturing company specializing in art supplies. It is known for its brand ''Crayola'' and best known for its crayons. The company is headquartered in Forks Township, Pennsylvan ...

disputed the patent given to Kehoe/C2C Technologies in a lawsuit which claimed that colored bubbles should be in the public domain. Kehoe died unexpectedly at the age of 43 in 2014.

Process

The colored bubble solution uses special dyes called

leuco dye A leuco dye (from the Greek λευκός ''leukos'': white ) is a dye which can switch between two chemical forms; one of which is colorless. Reversible transformations can be caused by heat, light or pH; resulting in examples of thermochromism, ...

s. For instance, the purple bubble uses a chemical called

crystal violet lactone Crystal violet lactone (CVL) is a leuco dye, a lactone derivate of crystal violet 10B. In pure state it is a slightly yellowish crystalline powder, soluble in nonpolar or slightly polar organic solvents. The central carbon in the leuco form is i ...

. After the bubble pops, the colored splatter disappears with friction, water or exposure to air. In a normal soap bubble,

surfactants Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsion#Emulsifiers , ...

reduce the surface tension of the water and allow the bubble to form. To create a colored bubble, dye molecules must bond to the surfactants. Each dye molecule in ''Zubbles'' is a structure known as a

lactone Lactones are cyclic carboxylic esters, containing a 1-oxacycloalkan-2-one structure (), or analogues having unsaturation or heteroatoms replacing one or more carbon atoms of the ring. Lactones are formed by intramolecular esterification of the co ...

ring. When the ring is closed, the molecule absorbs all visible light except for the color of the bubble. However, subjecting the lactone ring to air, water, or pressure causes the ring to open. This changes the molecule's structure to a straight chain which absorbs no visible light. Lactone rings can be produced whenever a long chain molecule contains

acid In computer science, ACID ( atomicity, consistency, isolation, durability) is a set of properties of database transactions intended to guarantee data validity despite errors, power failures, and other mishaps. In the context of databases, a sequ ...

functionality on one end, and

alcohol Alcohol most commonly refers to: * Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom * Alcohol (drug), an intoxicant found in alcoholic drinks Alcohol may also refer to: Chemicals * Ethanol, one of sev ...

functionality at the other. The two ends of the molecule react in a

condensation reaction In organic chemistry, a condensation reaction is a type of chemical reaction in which two molecules are combined to form a single molecule, usually with the loss of a small molecule such as water. If water is lost, the reaction is also known as a ...

, ejecting a water molecule. To drive the reaction back towards the long chain, pressure, heat or an excess of water must be added.

References

''Popular Science''
article, November 2005 {{Reflist

External links

Zubbles home page (archived)

Tim Kehoe's web site (archived)

Toy brands Colloidal chemistry