Roofing Material and Related Method

Abstract

A roofing material including a bitumen or other hot melt coating disposed across a base sheet of stitch-bonded fabric incorporating a blend of standard and bi-component polyester staple fibers stitch-bonded with a plurality of parallel stitch lines of stitching yarn running in the machine direction. The bicomponent fibers may be heat activated and cooled prior to application of the hot melt coating thereby providing dimensional stability.

Claims

1. A roofing material comprising a hot melt coating disposed across a base sheet of stitch-bonded fabric, the stitch-bonded fabric comprising a fleece substrate with a plurality of parallel stitch lines of stitching yarn stitched through the fleece substrate, the stitch lines running in the machine direction, the fleece substrate including a blend of standard polyester staple fibers in combination with bi-component polyester fibers, wherein the bi-component polyester fibers include a first polyester component having a first melting point and at least a second polyester component having a second melting point which is lower than the first melting point and lower than the melting point of the polyester staple fibers, and wherein at least a portion of the bi-component polyester fibers are heat fused to standard polyester fibers by the second polyester component at fusion junctions within the fleece substrate and wherein the total percentage of the second polyester component in the stitch-bonded fabric is in the range from about 5% to about 80%.

2. The invention as recited in claim 1, wherein the hot melt coating is bitumen.

3. The invention as recited in claim 1, wherein the total percentage of the second polyester component in the stich-bonded fabric is in the range from about 15% to 60%.

4. The invention as recited in claim 1, wherein the total percentage of the second polyester component in the stich-bonded fabric is in the range from about 15% to 45%.

5. The invention as recited in claim 1, wherein the total percentage of the second polyester component in the stich-bonded fabric is in the range from about 15% to 30%.

6. The invention as recited in claim 1, wherein the bi-component polyester fibers comprise a core of the first polyester component at least partially surrounded by a sheath of the second polyester component.

7. The invention as recited in claim 1, wherein the stitch-bonded fabric has a hot elongation in the machine direction at 8 daN (decaNewtons) of less than 9%.

8. The invention as recited in claim 1, wherein the stitch-bonded fabric has a hot elongation in the machine direction at 8 daN (decaNewtons) of less than 5%.

9. The invention as recited in claim 8, wherein the stitch-bonded fabric has a tensile strength to failure in the machine direction of not less than 85 pounds force per inch and a tensile strength to failure in the cross-machine direction of not less than 59 pounds force per inch.

10. The invention as recited in claim 9, wherein the base sheet of stitch-bonded fabric is free from applied pad finishes.

Description

DESCRIPTION

[0010] The present disclosure may be best understood through reference to the following non-limiting examples.

EXAMPLE 1

[0011] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00001 T19 Unfinished Heat Set Gauge (wales per inch) 7 5.8 Courses Per Inch 8.2 7.8 Stitch Density (wpi x cpi) 57.4 45.2 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 65% Polyester; 65% Polyester; 35% Core/Sheath 35% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-3 dpf, 3 Inch Staple Polyester-3 dpf, 3 Inch Staple Total Percentage Bicomponent 28.9% 28.9% In Fabric Fabric Basis Weight (grams 178 144 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 98.0 Machine Direction Tensile Strength (Ibs per inch), — 84.2 Cross Direction Cold Elongation, MD % — 23.0 Cold Elongation, CD % — 21.2 180° C. Hot Elongation (MD), 5kg — 3.1 load, % 180° C. Hot Elongation (MD), — 6.7 8daN load, %

EXAMPLE 2

[0012] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00002 T10 Unfinished Heat Set Gauge (wales per inch) 7 5.8 Courses Per Inch 8.2 7.8 Stitch Density (wpi × cpi) 57.4 45.2 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 50% Polyester; 50% Polyester; 50% Core/Sheath 50% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-6 dpf, 3 Inch Staple Polyester-6 dpf, 3 Inch Staple Total Percentage Bicomponent 41.3% 41.3% In Fabric Fabric Basis Weight (grams 177 143 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 112.3 Machine Direction Tensile Strength (Ibs per inch), — 82.8 Cross Direction Cold Elongation, MD % — 21.6 Cold Elongation, CD % — 23.3 180°C Hot Elongation (MD), 5kg — 0.9 load, % 180° C. Hot Elongation (MD), — 4.9 8daN load, %

EXAMPLE 3

[0013] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00003 T12 Unfinished Heat Set Gauge (wales per inch) 7 5.8 Courses Per Inch 18 17.9 Stitch Density (wpi x cpi) 126 103.8 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 50% Polyester; 50% Polyester; 50% Core/Sheath 50% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-6 dpf, 3 Inch Staple Polyester-6 dpf, 3 Inch Staple Total Percentage Bicomponent 40.5% 40.5% In Fabric Fabric Basis Weight (grams 177 160 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 120.7 Machine Direction Tensile Strength (Ibs per inch), — 76.4 Cross Direction Cold Elongation, MD % — 29.6 Cold Elongation, CD % — 22.3 180° C. Hot Elongation (MD), 5kg — 1.8 load, % 180° C. Hot Elongation (MD), — 8.3 8daN load, %

EXAMPLE 4

[0014] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00004 T16 Unfinished Heat Set Gauge (wales per inch) 7 5.8 Courses Per Inch 8.2 8.2 Stitch Density (wpi x cpi) 57.4 47.6 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 50% Polyester; 50% Polyester; 50% Core/Sheath 50% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-6 dpf, 3 Inch Staple Polyester-6 dpf, 3 Inch Staple Total Percentage Bicomponent 43.2% 43.2% In Fabric Fabric Basis Weight (grams 228 213 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 127.3 Machine Direction Tensile Strength (Ibs per inch), — 128.3 Cross Direction Cold Elongation, MD % — 25.2 Cold Elongation, CD % — 20.6 180° C. Hot Elongation (MD), 5kg — 1.8 load, % 180° C. Hot Elongation (MD), — 6.7 8daN load, %

EXAMPLE 5

[0015] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00005 T1 Unfinished Heat Set Gauge (wales per inch) 7 5.8 Courses Per Inch 8.2 8.2 Stitch Density (wpi x cpi) 57.4 47.6 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 75% Polyester; 75% Polyester; 25% Core/Sheath 25% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-6 dpf, 3 Inch Staple Polyester-6 dpf, 3 Inch Staple Total Percentage Bicomponent 20.3% 20.3% In Fabric Fabric Basis Weight (grams 167 143 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 85.4 Machine Direction Tensile Strength (Ibs per inch), — 68.3 Cross Direction Cold Elongation, MD % — 23 Cold Elongation, CD % — 71.8 180° C. Hot Elongation (MD), 5kg — 3.5 load, % 180° C. Hot Elongation (MD), — 7.1 8daN load, %

EXAMPLE 6

[0016] A single bar stitch-bonded base sheet for a bitumen-coated roofing material was formed having the following construction:

TABLE-US-00006 3559T1 Unfinished Heat Set Gauge (wales per inch) 7 6.7 Courses Per Inch 8.2 8.2 Stitch Density (wpi x cpi) 57.4 55.0 Fabric Fiber Composition 100% Polyester 100% Polyester Stitching Yarn 300 Denier, 72 Filament 300 denier, 72 filament Polyester polyester Stitching Fleece 75% Polyester; 75% Polyester; 25% Core/Sheath 25% Core/Sheath Bicomponent Polyester; Bicomponent Polyester; Polyester-6 dpf, 3 Inch Staple Polyester-6 dpf, 3 Inch Staple Total Percentage Bicomponent 19.6% 19.6% In Fabric Fabric Basis Weight (grams 145 132 per square meter) Stitch Notation 1-0/1-0 Chain Stitch 1-0/1-0 Chain Stitch Tensile Strength (Ibs per inch), — 87.9 Machine Direction Tensile Strength (Ibs per inch), — 59.7 Cross Direction Cold Elongation, MD % — 23.3 Cold Elongation, CD % — 62.9 180° C. Hot Elongation (MD), 5kg — 2.7 load, % 180° C. Hot Elongation (MD), — 5.6 8daN load, %

[0017] Each of these base sheets is adapted for coating with molten bitumen on one or both sides for subsequent cooling and use as a roofing material in accordance with standard roofing practices. As can be seen, in each of these examples the hot elongation in the machine direction at 8 daN (decaNewtons) is less than 9% and may be less than 5%. The tensile strength in the machine direction is not less than 85 pounds force per inch. The tensile strength in the cross-machine direction is not less than 59 pounds force per inch.

[0018] The use of the terms “a” and “an” and “the” and similar referents in the context of describing the disclosure are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

[0019] Preferred embodiments of this disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the disclosure to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.