Patent Choice: Conopco Soap Bar Enhances Active Diffusion and Scent Impact

Conopco Inc. issued a patent describing extruded soap bar compositions that deliver actives more efficiently and demonstrate higher scent impact.

See archived: Analyzing deposits from rinse-out hair products

According to the description, in crushed and peeled soap, the bar is prepared with a high water content, then spray-dried to reduce moisture levels and cool the soap, after which other ingredients are added. The soap is then extruded through an extruder and eventually cut and stamped to prepare the final bar of soap.

structure of soap

These soaps generally have high amounts of total fat (TFM) (60% to 80% w/w) and include both water-insoluble and water-soluble soaps. Water-insoluble soaps typically consist of large amounts of C16 and C18 upper chain soap (stearate and palmitate soap) and are included in bar soaps to provide structuring benefits. Water soluble soaps aid in cleaning and are usually C18:1 and 18:2 unsaturated sodium soaps (oleate soap) in combination with short chain fatty acids (C8 to C12, even up to C14 soap) .

See related: Formulation on trend; shampoo bar

The present inventors have identified a specific balance of soap ingredients that exhibits better bloom (perfume impact) and better deposition of actives, compared to conventional bar soaps.

Improving the impact of perfume, deposit of assets

US Patent 11414632
Publication date: August 16, 2022
Assignee: Conopco, Inc.

This patent specification describes a bar soap with enhanced fragrance impact and active deposit, which is achieved by balancing amounts of oleate soap with ricinoleate soap. Specifically, the Conopco inventors have found that when the amount of higher chain unsaturated fatty acid soaps, for example, oleate soaps, are minimized or eliminated from the soap composition, it is possible to achieve a higher perfume impact and better diffusion of active ingredients on the skin.

However, when such oleate soaps are not included, it is reported that it is difficult to extrude such soap masses. By replacing the oleate fraction with a certain amount of sodium ricinoleate, in combination with a short chain fatty acid soap (C-8 to C12), this challenge was overcome. The resulting compositions are said to exhibit significantly improved fragrance impact and increased active deposition, compared to conventional soaps comprising oleates.

Patent accessed August 23, 2022.

Donovan B. Sanford