Controlled release active agent carrier
AssigneeOmya International AG
InventorsPatrick A.C. Gane, Joachim Schölkopf
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Abstract
The present invention relates to carriers for the controlled release of active agents, comprising surface reacted natural or synthetic calcium carbonate, one or more active agents, wherein said one or more active agent is associated with said surface-reacted calcium carbonate, and wherein said surface-reacted natural or synthetic calcium carbonate is a reaction product of natural or synthetic calcium carbonate with carbon dioxide and one or more acids, wherein the carbon dioxide is formed in situ by the acid treatment and/or is supplied from an external source. It further relates to the preparation of loaded carriers, as well as their use in different applications.
Claims20
A method for preparing a loaded carrier comprising the steps of:
- (a) providing surface reacted calcium carbonate in powder or granule form that is reaction product of calcium carbonate with carbon dioxide and one or more acids in an aqueous environment, wherein the carbon dioxide is formed in situ by the acid treatment and/or is supplied from an external source,
- (b) providing an active agent in the form of a prepared solution or suspension;
- (c) contacting the surface reacted calcium carbonate with the active agent until a sufficient amount of the active agent is adsorbed onto and/or absorbed into the surface-reacted calcium carbonate;
- and
- (d) separating the loaded carrier from excess solution or suspension.
Dependencies are inferred from the claim text.