Patent ID: 8377862

Claim:
A spray-drying process to prepare a spray-dried powder comprising: (a) anionic detersive surfactant; (b) substantially free of zeolite builder; (c) substantially free of phosphate builder; (d) from 0 wt % to 10 wt % silicate salt; (e) optionally carbonate salt; (f) optionally polymeric material; and (g) optionally from 0 wt % to 10 wt % water, wherein, the process comprises the steps of: (i) spraying an aqueous slurry comprising from (a) anionic detersive surfactant; (b) substantially free of zeolite builder; (c) substantially free of phosphate builder; (d) from 0 wt % to 20 wt % silicate salt; (e) optionally carbonate salt; (f) optionally polymeric material; and (g) water, into a spray-drying zone, wherein the spray-drying zone comprises a vacuum, and wherein the spray-drying zone is under negative pressure of at least −80 Nm −2 and wherein the air inlet air temperature into the spray-drying zone is greater than 150° C.; and (ii) drying the aqueous slurry to form a spray-dried powder.