| abstract |
A method of coating a substrate with a cementitious composition by spraying, which comprises adding to the initial cementitious mixture one of the following components; a condensate of {b -naphthalene sulfonate-formaldehyde and a water-soluble polyalkylene oxide with a molecular weight of 100,000 - 8,000,000, the other component being added at the spray nozzle, further adding at the nozzle (preferably as a single component with the other material added to the nozzle) an accelerator selected from the group consisting of aluminum sulfate, aluminum hydroxide, and aluminum hydroxysulfate. In a preferred embodiment, the material added to the nozzle also contains a superplasticizer. |