Sprayable phosphate cementitious coatings and a method and apparatus for the production thereof

Abstract

A sprayed-on phosphate cement coating formed from the combination and reaction of a phosphoric acid solution and a base metal solution. The acid solution and base solution may be intermixed prior to spraying, during spraying, or on a substrate. The curing reaction rate of the phosphate cement coating and its final physical properties may be controlled by adding various retardants, accelerants, reducers, wetting agents, superplasticizers, buffers, water reducers, adhesive agents, hardening agents, and/or sequestrants to the precursor solutions. The curing rate and properties of the cement coating may be further controlled by adjusting the temperature of the precursor solutions and/or the target substrate.

I claim:  
     
         1 . A sprayed-on phosphate cement coating on a surface, the phosphate cement coating produced through a process comprising the steps of: 
 a) providing a first cementitious constituent;    b) providing a second cementitious constituent adapted to combine with the first cementitious constituent to produce a phosphate cement coating;    c) spraying the surface with the first cementitious constituent;    d) spraying the surface with the second cementitious constituent; and    e) reacting the first and second cementitious constituents to produce a phosphate cement coating.    
     
     
         2 . The coating of  claim 1  wherein the first constituent is a phosphoric acid and the second constituent is a metallic base.  
     
     
         3 . The coating of  claim 2  wherein the first constituent includes at least one of the following group: potassium phosphate, calcium phosphate, magnesium phosphate, sodium phosphate, aluminum phosphate, zinc phosphate; and wherein the second constituent includes at least one of the following group: magnesium oxide, magnesium hydroxide, calcium hydroxide, zirconium oxide, zirconium hydroxide, potassium hydroxide, sodium hydroxide, dolomite, zinc oxide, aluminum oxide, potash, calcium oxide, lithium carbonate, barium carbonate, molybdenum oxide, calcium hydroxide, aluminum hydroxide, tin oxide, tin, nickel oxide, magnesium hydroxide, iron oxide, titanium oxide, or wood ash.  
     
     
         4 . The coating of  claim 1  wherein the first constituent is a metallic base and the second constituent is a phosphoric acid.  
     
     
         5 . The coating of  claim 4  wherein the first constituent includes at least one of the following group: magnesium oxide, calcium oxide, magnesium hydroxide, calcium hydroxide, zirconium oxide, zirconium hydroxide, potassium hydroxide, sodium hydroxide, dolomite, zinc oxide, aluminum oxide, iron oxide, titanium oxide, wood ash; and wherein the second constituent includes at least one of the following: potassium phosphate, magnesium phosphate, zinc phosphate, ammonium phosphate, sodium phosphate, calcium phosphate, iron phosphate.  
     
     
         6 . The coating of  claim 1  further comprising the step of; 
 g) after step c) and before step d), adding at least one of the following to the first constituent: a retardant, an accelerant, a reducer, a wetting agent, a superplasticizer, a buffer, a water reducer, an adhesive agent, an air entraining agent, a hardening agent, a toughening agent, a smoothening agent and a sequestrant.  
 
     
     
         7 . The coating of claim  6 : 
 wherein the retardant comprises at least one of the following: ammonium nitrate, citric acid, acetic acid, boric acid, fine rice husk ash, chilled water, tri-sodium phosphate, colostrum, distilled water, deionized water, calcium citrate, calcium fluoride, sodium fluoride, tartaric acid, bentonite, diatomaceous earth, sodium carboxy-methycellulose, cellulose, and guar;    wherein the accelerant comprises at least one of the following: nitric acid, sodium chloride, calcium chloride, tin, tin oxide, calcium carbonate, potassium carbonate, carbonated water, hydrogen peroxide, potassium permanganate, sodium permanganate, sodium silicate, potassium silicate, sodium aluminate, aluminum hydroxide, fly ash, wollastonite, sodium hypochlorite, sodium chloride, potassium chloride, volcanic ash, distilled petroleum, and heated water;    wherein the adhesive agent comprises at least one of the following: sodium phosphate, fly ash, and aluminum phosphate;    wherein the hardening agent comprises at least one of the following: calcium fluorosilicate, sodium fluorosilicate, magnesium fluorosilicate, silicon carbide, boron nitride, tungsten carbide, molybdenum, molybdenum oxide, nickel oxide, chromium oxide, mullite, kyanite, alumina, ammonium meta-vanadate, ferrovanadium, vanadium oxide, aluminum, diamond, magnesium phosphate, sodium phosphate, zinc phosphate, colostrum, sodium silicate, potassium silicate, fly ash, zirconium hydroxide, zirconium oxide, zirconium silicate, zirconium stearate, silica fume, calcium silicate, titanium dioxide, cordierite, and aluminum phosphate;    wherein the smoothening agent comprises at least one of the following: fumed silica, colloidal silica, silica flour, Fe 2 O 3 , Fe 3 O 4 , kaolin, smectite, hectorite, potassium phosphate, potassium oxide, potassium hydroxide, and nitro cellulose, potassium peroxymonosulfate, sodium persulfate, sodium hypochlorite, Al2O3; and    wherein the toughening agent comprises at least one of the following: polyvinyl acetate and ground hard rubber.    
     
     
         8 . The coating of  claim 1 , further comprising the step of: 
 h) after step c) and before step d) adding a polymerizing agent to the first constituent.    
     
     
         9 . The coating of  claim 8 , further comprising the step of: 
 i) after step c) and before step d) adding a polymer initiator to the second constituent.    
     
     
         10 . The coating of  claim 1  wherein the surface is heated.  
     
     
         11 . The coating of  claim 1  wherein the surface is cooled.  
     
     
         12 . The coating of  claim 1  wherein the steps d) and e) occur substantially simultaneously and wherein the first and second constituents intermix during spraying.  
     
     
         13 . The coating of  claim 1  further comprising the step: 
 after step c) and before step d) mixing the first and the second constituents;  
 wherein steps d) and e) occur substantially simultaneously.  
 
     
     
         14 . The coating of  claim 1  wherein at least one of the constituents is heated.  
     
     
         15 . The coating of  claim 1  wherein at least one of the constituents is cooled.  
     
     
         16 . The coating of  claim 1  further comprising the step: 
 adding a colorant to the first constituent.  
 
     
     
         17 . A phosphate cement coating for a substrate produced by the following method: 
 aa) providing a first phosphoric acid liquid component;    bb) providing a second metallic base liquid component adapted to reactively combine with the first phosphoric acid liquid component to produce a phosphate cement coating;    cc) providing a cooling agent;    dd) spraying the substrate with the first phosphoric acid liquid component;    ee) spraying the substrate with the second metallic base liquid component;    ff) spraying the substrate with the cooling agent;    gg) mixing the first phosphoric acid liquid component, the second metallic base liquid component and the cooling agent to form a phosphate cement coating; and    hh) curing the phosphate cement coating.    
     
     
         18 . The phosphate cement coating of  claim 17  wherein the mixing of the first phosphoric acid liquid component, the second metallic base liquid component and the cooling agent occurs on the substrate.  
     
     
         19 . The phosphate cement coating of  claim 17  wherein the mixing of the first phosphoric acid liquid component, the second metallic base liquid component and the cooling agent occurs during spraying.  
     
     
         20 . The phosphate cement coating of  claim 17  wherein the mixing of the first phosphoric acid liquid component, the second metallic base liquid component and the cooling agent occurs in a liquid paint medium.  
     
     
         21 . The phosphate cement coating of  claim 17  wherein the cooling agent comprises at least one of the following: ammonium nitrate, chilled water, and water ice.  
     
     
         22 . The phosphate cement coating of  claim 17  wherein the substrate is a first layer of Portland cement and further including a second layer of Portland cement bondingly coating the phosphate cement coating.  
     
     
         23 . A phosphate cement, comprising: 
 a substrate;    a phosphoric acid portion;    a metallic base portion; and    a reaction-temperature controlling means;    wherein the phosphoric acid portion and the metallic base portion are applied to the substrate; and    wherein the phosphoric acid portion and the metallic base portion are reacted to form a phosphate cement material.    
     
     
         24 . The phosphate cement of  claim 23  wherein the phosphoric acid portion and the metallic base portion are intermixed prior to application to the substrate.  
     
     
         25 . The phosphate cement of  claim 23  wherein the phosphoric acid portion and the metallic base portion are sprayed onto the substrate and wherein the phosphoric acid portion and the metallic base portion are intermixed during spraying.  
     
     
         26 . The phosphate cement of  claim 23  wherein the phosphoric acid portion and the metallic base portion are intermixed on the substrate.  
     
     
         27 . The phosphate cement of  claim 23  wherein the phosphoric acid portion and the metallic base portion are intermixed in a liquid paint.  
     
     
         28 . The phosphate cement of  claim 23  wherein the reaction temperature controlling means is an additive added to a portion prior to application to the substrate.  
     
     
         29 . The phosphate cement of  claim 28  wherein the additive comprises at least on of the following: ammonium nitrate, citric acid, acetic acid, boric acid, fine rice husk ash, chilled water, tri-sodium phosphate, colostrum, distilled water, deionized water, calcium citrate, calcium fluoride, sodium fluoride, tartaric acid, bentonite, diatomaceous earth, sodium carboxy-methycellulose, cellulose, guar, nitric acid, sodium chloride, calcium chloride, tin, tin oxide, calcium carbonate, sodium carbonate, potassium carbonate, carbonated water, hydrogen peroxide, potassium permanganate, sodium permanganate, sodium silicate, potassium silicate, sodium aluminate, aluminum hydroxide, fly ash, wollastonite, distilled petroleum, and heated water.  
     
     
         30 . A method of toughening paint, comprising the steps of: 
 a) dissolving a phosphate source in the paint;    b) applying the paint to a surface; and    c) reacting the phosphate with a anions present in the paint to form a dispersed phosphate cement phase in the paint.    
     
     
         31 . The method of  claim 30  wherein the phosphate source includes at least one of the following group: potassium phosphate, calcium phosphate, magnesium phosphate, sodium phosphate, aluminum phosphate, and zinc phosphate.  
     
     
         32 . The method of  claim 31  wherein the phosphate source also includes silica.  
     
     
         33 . The method of  claim 31  wherein the paint includes at least one of the following: an oxide of a cation chosen from the group including Ca, Mg, Zn, Ti, K, Zr, Co, Al, Ni, MO, Cr and V, a hydroxide of a cation chosen from the group including Ca, Mg, Zn, Ti, K, Na, Zr, Co, Ni, Al, Ni and Cr; a carbonate of a cation chosen from the group including Ca, Mg, Co, Ba, Li and K; barium titanate; boric acid; tartric acid; acetic acid; citric acid; oxalic acid; and a nitrate of a cation chosen from the group including Na, K, and Ca.  
     
     
         34 . A method of tuckpointing a substrate with phosphate cement slurry, comprising the steps of: 
 a) imparting an electrical charge to the substrate;    b) imparting an opposite electrical charge to the phosphate cement slurry; and    c) applying the phosphate cement slurry to the substrate.    
     
     
         35 . The method of  claim 32  wherein the phosphate cement slurry contains ferromagnetic particles.  
     
     
         36 . The method of  claim 32  wherein step a) includes applying a charged solution to the substrate.  
     
     
         37 . The method of  claim 32  further comprising before step b), precoating the substrate with an alkali coating.  
     
     
         38 . The method of  claim 35  wherein the alkali coating is an aqueous solution including at least one of the following in solution: NaOH, KOH, caustic soda, and soda ash.  
     
     
         39 . A method of forming a laminate, comprising the steps of: 
 a) forming a first non-phosphate cement layer;    b) depositing a second, phosphate cement layer over the first non-phosphate cement layer;    c) depositing a third non-phosphate cement layer over the phosphate cement layer.    
     
     
         40 . The method of  claim 39 , wherein the first non-phosphate cement layer is Portland cement and the third non-phosphate cement layer is Portland cement.  
     
     
         41 . The method of  claim 39  wherein the first non-phosphate cement layer is Portland cement and the third non-phosphate cement layer is asphalt.  
     
     
         42 . The method of  claim 39  wherein the first non-phosphate cement layer is asphalt and the third non-phosphate cement layer is Portland cement.