Acid treated polyester polyurethane foam end wrap
AssigneeThe Procter & Gamble Company
InventorsDavid Martin Adrion, Lloyd Bruce Hartsough
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Abstract
A superior end wrap comprising a particular type of open-celled polyurethane foam of specified porosity and thickness which foam has been treated with certain types of weak carboxylic acids. Also disclosed is a permanent waving process using said acid treated end wraps.
Claims9
An end wrap for use in the permanent waving process which comprises a permeable flexible wafer of open-celled polyester polyurethane foam having a thickness of from about one-sixteenth inch to about one sixty-fourth inch, an average pore incidence within the range of from about 30 to 120 pores per linear inch and, contained in said end wrap, a solid, carboxylic acid having a pK.sub.1 of from about 2.5 to about 6.0 and a water-solubility of from about 0.1 to 10.0 parts acid per 100 parts water at 15.degree. -20.degree. C., said acid being present at a level of at least 5 milligrams of acid per cubic inch of foam.
The process of imparting a permanent wave to hair which comprises the steps of forming the hair into tresses, wrapping about the end of each tress a permeable, flexible wafer of polyester polyurethane foam having a thickness of from about one-sixteenth inch to about one sixty-fourth inch, said wafer containing a solid, weak, carboxylic acid having a pK.sub.1 of from about 2.5 to about 6.0 and a water solubility of from about 0.1 to 10.0 parts acid per 100 parts water at 15.degree. C. - 20.degree. C., said acid being present at a level of at least 5 milligrams of acid per cubic inch of wafer, winding each tress on a cylindrical body, saturating each wound tress with a keratin-reducing composition and thereafter neutralizing the action on the hair of said keratin-reducing composition.
Dependencies are inferred from the claim text.