Alkali metal bicarbonate particles with increased dissolution time
AssigneeSolvay SA
InventorsDavid Jean Lucien Savary, Jean-Yves Seguin, Karine Cavalier
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Abstract
Powder compositions comprising alkali metal bicarbonate particles and an additive. A process for preparing alkali metal bicarbonate particles by spray-drying of an aqueous solution or suspension comprising 1-10% by weight of alkali metal bicarbonate and a resin acid or a fatty acid as additive. A process for preparing alkali metal bicarbonate particles by co-grinding the alkali metal bicarbonate in the presence of a resin acid as additive. A process for preparing alkali metal bicarbonate particles by fluidized bed coating of the alkali metal bicarbonate in the presence of a resin acid, fatty acid or a wax as additive.
Claims15
A process for producing alkali metal bicarbonate particles comprising:
- co-grinding of an alkali metal bicarbonate in the presence of 0.1 to 20 parts by weight of a resin acid, per 100 parts by weight of the alkali metal bicarbonate
- wherein the resin acid is selected from the group consisting of abietic acid (abieta-7,13-dien-18-oic acid), neoabietic acid, dehydroabietic acid, and palustric acid;
- and
- wherein the alkali metal bicarbonate particles are suitable as foaming agents for polymers.
Alkali metal bicarbonate particles, having a particle size distribution of D50 of at most 200 μm, a dissolution time in the range of 20 to 200 seconds, and a CO2 release maximum temperature of at least 125° C., as determined by thermogravimetric analysis (TGA).
A method for increasing dissolution time of alkali metal bicarbonate particles, comprising spray-drying or co-grinding or fluidized bed coating alkali metal bicarbonate in the presence of an additive selected from the group consisting of a resin acid, a fatty acid, and a wax.
Dependencies are inferred from the claim text.