Gypsum Gray Back
Four plys of 100% recycled brown fiber make the Gray Back grade. This backing paper fits perfectly with the Gypsum Cream Face paper to produce a quality wallboard construction that can be used in all applications. It is available in 38# and 42# per thousand square feet (MSF). Contact or Customer Service Department for any available variations of this.
All Republic Paperboard products can be customized to fit your needs! Contact our sales team and we’ll be happy to work with you to create the product that meets your exact specifications. Contact Us Today
GENERAL SPECIFICATIONS
| Critical Properties | UOM | Min | Target | Max | Test Method | Method Comments |
|---|---|---|---|---|---|---|
| Basis Weight | lbs/msf | -2.0 | as ordered | +2.0 | ABB Scanner | |
| Moisture | weight % | 7.5 | 9.00 | 10.5 | ABB Scanner | |
| Porosity | sec/100cc | Grade Dependent | Autoline | Gurley; 5-min 300°F cure | ||
| Face Cobb | g/100cm^2 | 0.30 | 0.80 | 1.50 | T-441 | 10-min 250°F cure; 3-min 120°F water |
| Bond Cobb | g/100cm^2 | 0.50 | 0.70 | 1.2 | T-441 | 10-min 250°F cure; 3-min 120°F water |
| ZDT | psi | -20 | BW dependent* | ----- | T-541 | Uncured |
| MD Tensile | lbs/in | -10 | BW dependent* | ----- | Autoline | 5-min 300°F cure |
| CD Tensile | lbs/in | -4 | BW dependent* | ----- | Autoline | 5-min 300°F cure |
| Smoothness Sheffield | SU | 350 | Autoline | 5-min 300°F cure | ||
| Coefficient of Friction | degrees | Grade Dependent | T-815 | Uncured; test 3x, record 3rd value | ||
| Expansion 180 sec | % | -0.30 | BW dependent* | +.30 | CD Wet | Uncured; 10” strip |
*BW Dependent Targets:
| BW | 38/42 | 48 | 54 |
|---|---|---|---|
| MD Tensile | 83 | 90 | 95 |
| CD Tensile | 28 | 32 | 35 |
| ZDT | 80 | 75 | 73 |
| Expansion | 1.15 | 1.0 | 0.80 |
Additional Requirements:
Surface Quality – Paper shall be uniform in appearance and formation. Examples of defects include, but are not limited to: orange peel, discoloration, tiger striping, streaking, spotting (dirty face), fuzzing, fish hooks, cockles, excessive wire, felt, press roll, or other marking.
Flatness – Paper shall lie flat - free of cockles, edge warp, curling, and grooves.
Holes – Paper shall be reasonably free from holes (no repetitive MD holes). Holes smaller than 3" may be patched (no more than 2 per roll).
Roll Quality – Rolls shall be tightly wound. No telescoping. No wrinkles. No crushed or damaged cores. Splices shall be clearly marked. No splices 1" from the top. Core diameter: 4".
Physical Damage – Paper shall be free from physical defects including, but not limited to tears, edge nicks, excess moisture.
Packaging – Rolls shall be packaged to prevent damage during transport (ex: plastic wrapped). Rolls shall be marked to indicate bond side and labeled with roll number, basis weight, MD & CD tensile strength, top & bond cobb, and porosity.
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Established in 1999, Republic Paperboard Company occupies a 70 acre site in the industrial park in Lawton, Oklahoma. All Manufacturing, Marketing, Sales and Service personnel are based in Lawton.
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