Plaster patching compositions and methods for making and using same

1. A plaster patching composition, comprising:

lime comprising

calcium magnesium hydroxide in an amount of from about 5 to about 16 wt %, and

calcium magnesium hydroxide oxide in an amount of from about 5 to about 16 wt %,

optionally first crystalline silica present in an amount of 0 to <0.2 wt %;

sand comprising

second crystalline silica present in an amount of from about 34 wt % to about 48 wt %;

perlite present in an amount of from about 2 wt % to about 12 wt %; and

gypsum comprising

calcium sulfate hemihydrates present in an amount of from about 12 wt % to about 32 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

2. A method of making the plaster patching composition of claim 1 , comprising:

blending together lime, perlite, sand, and gypsum, under ambient conditions, to produce a uniform dry powder patching plaster composition, and

adding water in an amount sufficient to produce a patching plaster composition having a viscosity of from about 200,000 to about 300,000 cp.

3. The method of claim 2 , wherein the viscosity is from about 225,000 to about 275,000 cp.

4. The method of claim 3 , wherein the viscosity is about 250,000 cp.

5. A method of repairing plaster, comprising:

stabilizing any loose plaster and/or lath in an area to be repaired, the area having a surface; and

applying at least a first coat of the plaster patching composition of claim 1 to the area.

6. A plaster patching composition, comprising:

lime comprising

calcium magnesium hydroxide in an amount of from about 5 to about 16 wt %,

calcium magnesium hydroxide oxide in an amount of from about 5 to about 16 wt %,

optionally calcium hydroxide in an amount of from about 3 to about 8 wt %,

optionally magnesium hydroxide in an amount of from about >0 to about 9 wt %,

optionally magnesium oxide in an amount of from about >0 to about 9 wt %, and

optionally first crystalline silica in an amount of <0.1 wt %;

second crystalline silica in an amount of from about 34 wt % to about 48 wt %;

perlite in an amount of from about 2 wt % to about 12 wt; and

calcium sulfate hemihydrates in an amount of from about 12 wt % to about 32 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

7. The plaster patching composition of claim 6 , wherein the composition is a pre-mix composition in the form of a dry powder.

8. The plaster patching composition of claim 6 , wherein

calcium magnesium hydroxide is present in an amount of from about 7 to about 14 wt %,

calcium magnesium hydroxide oxide is present in an amount of from about 7 to about 14 wt %,

calcium hydroxide is present in an amount of from about 3 to about 7 wt %,

magnesium hydroxide is present in an amount of from about 2.5 to about 4.5 wt %,

magnesium oxide is present in an amount of from about 2.5 to about 4.5 wt %,

first crystalline silica in the lime is present in an amount of from 0 to <0.1 wt %,

second crystalline silica is present in an amount of from about 39 wt % to about 43 wt %,

perlite is present in an amount of from about 6 wt % to about 8 wt, and

calcium sulfate hemihydrate is present in an amount of from about 20 wt % to about 24 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

9. The plaster patching composition of claim 6 , wherein

calcium magnesium hydroxide is present in an amount of from about 10 to about 14 wt %,

calcium magnesium hydroxide oxide is present in an amount of from about 10 to about 14 wt %,

calcium hydroxide is present in an amount of from about 4 to about 8 wt %,

magnesium hydroxide is present in an amount of from about 0 to about <0.1 wt %,

magnesium oxide is present in an amount of from about 0 to about <0.1 wt %,

first crystalline silica in the lime is present in an amount of 0 to about <0.1 wt %,

second crystalline silica is present in an amount of from about 39 wt % to about 43 wt %,

perlite is present in an amount of from about 6 wt % to about 8 wt, and

calcium sulfate hemihydrate is present in an amount of from about 20 wt % to about 24 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

10. The plaster patching composition of claim 6 , wherein

calcium magnesium hydroxide is present in an amount of about 9.2 wt %,

calcium magnesium hydroxide oxide is present in an amount of about 9.2 wt %,

calcium hydroxide is present in an amount of about 4.6 wt,

magnesium hydroxide is present in an amount of about 3.5 wt %,

magnesium oxide is present in an amount of about 3.5 wt,

first crystalline silica in the lime is optionally present in an amount of from 0 to about <0.1 wt %,

second crystalline silica is present in an amount of about 41 wt %,

perlite is present in an amount of about 7 wt %, and

calcium sulfate hemihydrates is present in an amount of about 22 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

11. The plaster patching composition of claim 6 , wherein

calcium magnesium hydroxide is present in an amount of about 12 wt %,

calcium magnesium hydroxide oxide is present in an amount of about 12 wt %,

calcium hydroxide is present in an amount of about 6 wt %,

magnesium hydroxide is optionally present in an amount of from 0 to about <0.1 wt %,

magnesium oxide is optionally present in an amount of from 0 to about <0.1 wt %,

first crystalline silica in the lime is optionally present in an amount of from 0 to about <0.1 wt %,

second crystalline silica is present in an amount of about 41 wt %,

perlite is present in an amount of about 7 wt %, and

calcium sulfate hemihydrates is present in an amount of about 22 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

12. A method of making the plaster patching composition of claim 7 , comprising blending together the lime, crystalline silica, perlite and calcium sulfate hemihydrate under ambient conditions, to produce a uniform dry powder pre-mix patching plaster composition.

13. A method of constituting the plaster patching composition of claim 7 , comprising:

blending a quantity of the uniform dry powder pre-mix patching plaster composition with a diluent in an amount sufficient to produce a patching plaster patching paste having a viscosity of from about 200,000 to about 300,000 cp.

14. The method of claim 13 , wherein the viscosity is from about 225,000 to about 275,000 cp.

15. The method of claim 13 , wherein the viscosity is about 250,000 cp.

16. A dry pre-mix plaster patching composition, consisting of:

lime consisting of

calcium magnesium hydroxide in an amount of from about 5 to about 16 wt %,

calcium magnesium hydroxide oxide in an amount of from about 5 to about 16 wt %,

optionally calcium hydroxide in an amount of from about 3 to about 8 wt %,

optionally magnesium hydroxide in an amount of from about >0 to about 6 wt %,

optionally magnesium oxide in an amount of from about >0 to about 9 wt %, and

optionally first crystalline silica in an amount of <0.1 wt %;

second crystalline silica in an amount of from about 34 wt % to about 48 wt %;

perlite in an amount of from about 2 wt % to about 12 wt %; and

calcium sulfate hemihydrate in an amount of from about 12 wt % to about 32 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

17. A plaster patching composition, comprising:

lime present in an amount of from about 20 to about 40 wt %, the lime comprises

calcium magnesium hydroxide present in an amount of from about 5 to about 16 wt %, and

calcium magnesium hydroxide oxide present in an amount of from about 5 to about 16 wt %;

crystalline silica present in an amount of from about 34 wt % to about 48 wt %;

perlite is present in an amount of from about 2 wt % to about 12 wt %; and

calcium sulfate hemihydrate present in an amount of from about 12 wt % to about 32 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

18. A plaster patching composition, comprising:

lime in an amount of from about 25 to about 35 wt %;

sand in an amount of from about 36 to about 46 wt %;

perlite in an amount of from about 5 to about 9 wt %; and

gypsum in an amount of from about 17 to about 27 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

19. The plaster patching composition according to claim 18 , wherein

lime is present in an amount of from about 29 to about 31 wt %;

sand is present in an amount of from about 39 to about 43 wt %;

perlite is present in an amount of from about 6 to about 8 wt %; and

gypsum is present in an amount of from about 21 to about 23 wt %,

wherein wt % is based on the total weight of the plaster patching composition.

20. The plaster patching composition according to claim 18 , wherein

lime is present in an amount of 30 wt %;

sand is present in an amount of about 41 wt %;

perlite is present in an amount of about 7 wt %; and

gypsum is present in an amount of about 22 wt %,

wherein wt % is based on the total weight of the plaster patching composition.