Agent and method for modifying surface layer of cement structures
AssigneeNissan Chemical Industries, Ltd.
InventorsMasamichi Obitsu, Takahiro Hori, Toyoji Koinuma, Yuriko Sakaguchi
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Abstract
An agent and method for modifying a surface layer of hardened cement structures or substrates with use of the agent which comprises in a specified ratio of an alkali silicate solution and a sodium naphthalenesulfonate-formaldehyde condensate. Said agent has an excellent stability and a remarkable permeability into the cement structure to form a deeper strengthened surface layer thereon.
Claims13
A method for modifying a surface layer of cement structures, which comprises steps of applying on surface of the structure an agent comprising 100 parts by weight of an alkali silicate solution and 0.01 to 5 parts by weight of a condensate of sodium naphthalenesulfonate and formaldehyde, in which said alkali silicate solution has a SiO.sub.2 /M.sub.2 O mole ratio of 1 to 50, wherein M represents an alkali metal atom, or a substituted or unsubstituted ammonium cationic radical, and has a SiO.sub.2 content of 1 to 50 weight %, impregnating the surface layer of said structure with said agent, and then leaving to stand or positively drying the treated structure.
A method for repairing a deteriorated surface layer of cement structures, which comprises steps of applying on the deteriorated surface of the cement structure an agent comprising 100 parts by weight of an alkali silicate solution and 0.01 to 50 parts by weight of a condensate of sodium naphthalenesulfonate and formaldehyde, in which said alkali silicate solution has a SiO.sub.2 /M.sub.2 O mole ratio of 1 to 50, wherein M represents an alkali metal atom, or a substituted or unsubstituted ammonium cationic radical, and has a SiO.sub.2 content of 1 to 50 weight %, impregnating the surface layer of said structure with said agent, leaving to stand or positively drying the treated structure, applying a freshly prepared cement material on the treated surface of said structure, and then curing the applied cement material.
Dependencies are inferred from the claim text.