PROCESS OF PRODUCING ROOFING SHINGLE COATING ASPHALT — OWENS CORNING INTELLECTUAL CAPITAL, LLC

1. A process of producing a roofing shingle coating asphalt from an asphalt feedstock comprising the following steps: adding wax and blowing catalyst to the asphalt feedstock; and then blowing the asphalt feedstock to produce the coating asphalt; the coating asphalt having a softening point within a range of from 19O 0 F (88 0 C) to 235 0 F (113 0 C) and having a penetration of at least 15 dmm at 77 0 F (25 0 C).

2. The process of claim 1 wherein the blowing catalyst comprises phosphoric acid added in an amount within a range of from 0.1% to 5% by total weight of the phosphoric acid and the asphalt.

3. The process of claim 1 wherein the wax has a melt point of at least 75 0 C.

4. The process of claim 1 wherein the feedstock asphalt comprises paving asphalt.

5. The process of claim 1 wherein the feedstock asphalt comprises polymer modified asphalt.

6. The process of claim 1 wherein the coating asphalt has a melt viscosity within a range of from 130 cps to 420 cps at 400 0 F (204 0 C).

7. The process of claim 1 wherein the coating asphalt has a durability of greater than 60 cycles in a weatherometer.

8. The process of claim 1 wherein the coating asphalt has a stain index less than 10.

9. The process of claim 1 further comprising adding polymer to the asphalt at any time during the process.

10. The process of claim 1 further comprising blending polymer modified asphalt with the coating asphalt produced by the process.

11. A process of producing a roofing shingle coating asphalt from an asphalt feedstock comprising: partially blowing the asphalt feedstock to raise its softening point to a first softening point that is lower than a target range; adding wax to the partially blown asphalt; and further blowing the asphalt to further raise its softening point to a second softening point that is within the target range; and

adding blowing catalyst to the asphalt before or during the blowing; the process producing a coating asphalt having a softening point within the target range of from 19O 0 F (88 0 C) to 235 0 F (113 0 C) and having a penetration of at least 15 dmm at 77 0 F (25 0 C).

12. The process of claim 11 wherein the blowing catalyst comprises phosphoric acid added in an amount within a range of from 0.1% to 5% by total weight of the phosphoric acid and the asphalt.

13. The process of claim 11 wherein the wax has a melt point of at least 75 0 C.

14. The process of claim 11 wherein the feedstock asphalt comprises paving asphalt.

15. The process of claim 11 wherein the feedstock asphalt comprises polymer modified asphalt.

16. The process of claim 11 wherein the coating asphalt has a melt viscosity within a range of from 130 cps to 420 cps at 400 0 F (204 0 C).

17. The process of claim 11 wherein the coating asphalt has a durability of greater than 60 cycles in a weatherometer.

18. The process of claim 11 wherein the coating asphalt has a stain index less than 10.

19. The process of claim 11 further comprising adding polymer to the asphalt at any time during the process.

20. The process of claim 11 further comprising blending polymer modified asphalt with the coating asphalt produced by the process.

21. A process of producing a roofing shingle coating asphalt from an asphalt feedstock comprising the following steps: blowing the asphalt feedstock with a high level of blowing catalyst such that the blowing step is effective to raise the softening point of the asphalt to within a target range of from 19O 0 F (88 0 C) to 235 0 F (113 0 C) and to lower the penetration of the asphalt to within a target range of from 15 dmm to 28 dmm at 77 0 F (25 0 C), the blowing step raising the melt viscosity of the asphalt to higher than a target range; and adding wax to the blown asphalt to lower its melt viscosity to within the target range of from 130 cps to 420 cps at 400 0 F (204 0 C).

22. The process of claim 21 wherein the blowing catalyst comprises phosphoric acid.

23. The process of claim 22 wherein the phosphoric acid is added in an amount within a range of from 2% to 7% active by total weight of the phosphoric acid and the asphalt.

24. The process of claim 21 wherein the feedstock asphalt comprises paving asphalt.

25. The process of claim 21 wherein the wax is added in an amount within a range of from 0.5% to 8% by total weight of the wax and the asphalt.

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