Treatment composition with delivery particles based on modified chitosan

A treatment composition comprising a treatment adjunct and a population of delivery particles,

• wherein the delivery particles comprise a core and shell surrounding the core,
• wherein the core comprises a benefit agent,
• wherein the shell comprises a polymeric material that is a reaction product of at least one modified chitosan and at least one electrophile,
• wherein the population of delivery particles is obtainable a process comprising the following steps:
• forming a water phase by dissolving or dispersing chitosan in an aqueous acidic medium at a pH of 6.5 or less and a temperature of at least 25° C.,
• the chitosan having free amine moieties;
• forming an oil phase comprising combining together at least one benefit agent and at least one electrophile, preferably at least one polyisocyanate, optionally with an added oil;
• forming an emulsion by mixing under high shear agitation the oil phase into an excess of the water phase, thereby forming droplets of the oil phase dispersed in the water phase;
• adding to the water phase and/or to the emulsion, preferably at least to the water phase, a modifying compound,
• the modifying compound comprising one or more of an epoxide, an aldehyde, or an α,β-unsaturated compound,
• the modifying compound reacting with the free amine moieties of the chitosan;
• optionally adjusting the pH of the emulsion to a pH of 4 or greater;
• heating the emulsion to at least 40° C., for a time sufficient to form a shell at an interface of the droplets with the water phase, the shell surrounding the core.

A treatment composition comprising a treatment adjunct and a population of delivery particles,

• wherein the delivery particles comprise a core and shell surrounding the core,
• wherein the core comprises a benefit agent,
• wherein the shell comprises a polymeric material that is a reaction product of at least one modified chitosan and at least one electrophile,
• the modified chitosan comprising a reaction product of chitosan and a modifying compound,
• wherein the modifying compound comprises an epoxide, an aldehyde, or an α,β-unsaturated compound that covalently bonds with the chitosan,
• wherein the population of delivery particles is obtainable a process comprising the following steps:
• dissolving or dispersing chitosan into a water phase, the chitosan having amine moieties;
• combining the water phase and the modifying compound;
• optionally adjusting the pH of the water phase to pH 3.0 or higher, preferably from pH 3.0 to pH 6;
• optionally adjusting the temperature of the water phase to 25° C. or greater;
• mixing the water phase for a period of time, thereby forming a modified chitosan,
• wherein the modifying compound is covalently bonded through CN bonds with the amine moieties of the chitosan,
• wherein the modified chitosan remains dissolved in the water phase;
• providing an oil phase comprising dissolving together at least one benefit agent comprising an oil, and at least one electrophile, preferably at least one polyisocyanate, optionally with a second oil;
• forming an emulsion by mixing under high shear agitation the oil phase into the water phase, thereby forming droplets of the oil phase and benefit agent dispersed in the water phase;
• heating the emulsion to at least 40° C., for a time sufficient to form the shell at an interface of the droplets with the water phase, the shell surrounding the core.