Soap bubble for its soaps in 1886 using a painting by John Everett Millais of a child playing with bubbles. The Chicago company Chemtoy began selling bubble solution in the 1940s, and bubble solution has been popular with children ever since. According to one industry estimate, retailers sell around 200 million bottles annually. A bubble is made of transparent water enclosing transparent air. However the soap film is as thin as the visible light wavelength, resulting in interferences. This creates iridescence which, together with the bubble's spherical shape and fragility, contributes to its magical effect on children and adults alike. Each colour
Pears (soap) article and under Marketing below. Following Barratt's death in April 1914 Lever Brothers took a major shareholding in A & F Pears. The takeover process was completed in 1920 and marketing and other secondary functions moved to Port Sunlight in north-west England, but production continued at Isleworth. In the mid to late 1950s each batch of soap, about 12 a day, was tested to ensure the absence of excess alkali or free fatty acid. Production moved to Port Sunlight in the 1960s when Unilever, successor to Lever Brothers, set up a cosmetic development laboratory on the Isleworth site. A major