Colored metal flake surfaced roofing materials
View Patent ↗The present invention relates to roofing materials for roofs, sidewalls and other exterior surfaces exposed to the weather such as, but not limited to, asphaltic and non-asphaltic roofing materials, wherein color coated metal flakes cover up to 100% of the weathering surface of the roofing materials. The metal flakes are coated with a colored coating material by fluidizing the flakes in an air stream, spraying pressurized air and colored coating material, and curing the coated metal flakes. The present invention also relates to methods of making roofing materials.
1. A method of producing a colored-flake coated roofing material comprising:
providing a plurality of metal flakes;
roughening a surface of the plurality of metal flakes;
fluidizing the plurality of metal flakes in an air stream;
spraying a first liquid colored-coating material in the air stream to coat the plurality of metal flakes to produce coated metal flakes;
curing the coated metal flakes; and
applying the coated metal flakes to a base roofing material to produce a colored-flake coated roofing material.
2. The method of claim 1 , further comprising the plurality of metal flakes having an initial weight, and the coated metal flakes having a final weight at least 20% greater than the initial weight.
3. The method of claim 1 , wherein fluidizing the plurality of metal flakes in a stream comprises preconditioning the plurality of metal flakes by fluidizing the plurality of metal flakes in a stream of pressurized air prior to spraying a coating material.
4. The method of claim 1 , wherein the plurality of metal flakes are selected from the group consisting of copper flakes, tin flakes, zinc flakes, aluminum flakes, steel flakes, stainless steel flakes, bronze flakes, and combinations thereof.
5. The method of claim 1 , wherein the plurality of metal flakes are of a size greater than the size of flakes passing through a U.S. Standard Sieve #50.
6. The method of claim 1 , wherein the compressed air is pressurized at 30 to 120 psi.
7. The method of claim 1 , wherein the first colored-coating material is a water based paint.
8. The method of claim 1 , wherein the first colored-coating material is a mixture of silicate and water.
9. The method of claim 8 , wherein the mixture is between about 40 and 60 percent silicate.
10. The method of claim 1 , wherein the fluidizing and spraying steps continue for 15 to 45 minutes.
11. The method of claim 1 , wherein curing the coated metal flakes comprises heat curing.
12. The method of claim 11 , wherein the heat curing is carried out at between about 800 and 1000 degrees F.
13. The method of claim 1 , wherein curing the coated metal flakes comprises chemically curing.
14. The method of claim 1 , further comprising spraying a second coating material to create an outer coating on the plurality of metal flakes.
15. The method of claim 14 wherein the second coating material is darker than the first colored-coating material.
16. The method of claim 1 , wherein the fluidizing and spraying steps are carried out at between 250 and 500 degrees F.
17. A method of producing a colored-flake coated roofing material comprising:
providing a plurality of metal flakes;
fluidizing the plurality of metal flakes in an air stream;
spraying a first liquid colored-coating material in the air stream to coat the plurality of metal flakes to produce coated metal flakes, wherein the colored-coating material is a water based paint;
curing the coated metal flakes; and
applying the coated metal flakes to a base roofing material to produce a colored-flake coated roofing material.