Claims
- 1. A shingle comprising:
- a) a first element including a reinforcing web, a first asphaltic binder, and a first adherent surfacing material, and
- b) a second element overlaid on the first element, the second element including a layer of second asphaltic binder and a second adherent surfacing material, the layer of second asphaltic binder being sufficiently extensible to elongate in a crack-free manner when the shingle is subjected to a strain of at least 1 percent at a temperature of -1.degree. C. after aging at 70.degree. C. for two weeks, the second element comprising a plurality of discontinuous sections.
- 2. A shingle according to claim 1 wherein the layer of second asphaltic binder is sufficiently extensible to elongate in a crack-free manner when the shingle is subjected to a strain of at least 2 percent after aging at 70.degree. C. for two weeks.
- 3. A shingle according to claim 1 wherein the layer of second asphaltic binder is sufficiently extensible to elongate in a crack-free manner when the shingle is subjected to a strain of at least 2 percent after aging at 70.degree. C. for ten weeks.
- 4. A shingle having a backcoating, the shingle comprising:
- a) a first element including a reinforcing web, a first asphaltic binder having a predefined cracking temperature, and a first adherent surfacing material, and
- b) a second element overlaid on the first element, the second element including a layer of second asphaltic binder and a second adherent surfacing material, the layer of second asphaltic binder having a predefined cracking temperature, the predefined cracking temperature of the second asphaltic binder being lower than the predefined cracking temperature of the first asphaltic binder, the cracking temperature being measured by a three point bend test in which a normal force is applied to the backcoating of the shingle, the second element comprising a plurality of discontinuous sections.
- 5. A shingle according to claim 4 wherein the cracking temperature is measured after aging the shingle for 5 weeks at 70.degree. C.
- 6. A shingle according to claim 5 wherein the cracking temperature is measured after aging the shingle for 10 weeks at 70.degree. C.
Parent Case Info
This is a continuation of application(s) Ser. No. 07/898,793 filed on Jun. 15, 1992, now U.S. Pat. No. 5,347,785.
US Referenced Citations (9)
Continuations (1)
|
Number |
Date |
Country |
Parent |
898793 |
Jun 1992 |
|