Low density paperboard
A paperboard including a solid bleached sulfate paperboard substrate and a coating applied to the paperboard substrate to form a coated structure, the coated structure having a basis weight, a caliper thickness and a Parker Print Surf smoothness, the Parker Print Surf smoothness being at most about 3 microns, the basis weight being at most about Y 1 pounds per 3000 ft 2 , wherein Y 1 is a function of the caliper thickness (X) in points and is calculated as follows: Y 1 =3.79+13.43X−0.1638X 2 .
1. A paperboard comprising:
a solid bleached sulfate (SBS) paperboard substrate; and
a coating applied to said paperboard substrate to form a coated structure, said coated structure having a basis weight, a caliper thickness and a Parker Print Surf smoothness, said Parker Print Surf smoothness being at most 3 microns, said basis weight being at most Y 2 pounds per 3000 ft 2 , wherein Y 2 is a function of said caliper thickness (X) in points and is calculated as follows:
Y 2 =3.71+13.14 X− 0.1602 X 2 .
2. The paperboard of claim 1 wherein said coating includes at least a basecoat and a topcoat, wherein said basecoat is positioned between said topcoat and said SBS paperboard substrate.
3. The paperboard of claim 2 wherein said coating further includes an intermediate coating layer positioned between said basecoat and said topcoat.
4. The paperboard of claim 1 wherein said coating includes starch.
5. The paperboard of claim 1 wherein said coating includes coarse ground calcium carbonate and high aspect ratio clay.
6. The paperboard of claim 1 wherein said basis weight is at most Y 3 pounds per 3000 ft 2 , wherein Y 3 is calculated as follows:
Y 3 =3.63+12.85 X− 0.1566 X 2 .
7. The paperboard of claim 1 wherein said basis weight is at most Y 4 pounds per 3000 ft 2 , wherein Y 4 is calculated as follows:
Y 4 =3.50+12.41 X− 0.1513 X 2 .
8. The paperboard of claim 1 wherein said Parker Print Surf smoothness is at most 2.5 microns.
9. The paperboard of claim 1 wherein said Parker Print Surf smoothness is at most 2.0 microns.
10. The paperboard of claim 1 wherein said Parker Print Surf smoothness is at most 1.5 microns.
11. The paperboard of claim 1 wherein said coating includes at least one pigment, and wherein each of said pigments in said coating is an inorganic pigment.
12. The paperboard of claim 1 with the proviso that said SBS paperboard substrate is substantially free of chemical bulking agents.
13. The paperboard of claim 1 wherein said SBS paperboard substrate has a basis weight of at least 85 pounds per 3000 ft 2 .
14. The paperboard of claim 1 wherein said SBS paperboard substrate is a single-ply substrate.
15. The paperboard of claim 1 wherein said SBS paperboard substrate consists essentially of chemical pulp.
16. A paperboard comprising:
a solid bleached sulfate (SBS) paperboard substrate; and
a coating applied to said paperboard substrate to form a coated structure, said coated structure having a basis weight, a caliper thickness and a Parker Print Surf smoothness, said Parker Print Surf smoothness being at most 3 microns, said basis weight being at most Y 2 ′ pounds per 3000 ft 2 , wherein Y 2 ′ is a function of said caliper thickness (X) in points and is calculated as follows:
Y 2 ′=35.55+8.173 X+ 0.01602 X 2 .
17. The paperboard of claim 16 wherein said basis weight is at most Y 3 ′ pounds per 3000 ft 2 , wherein Y 3 ′ is calculated as follows:
Y 3 ′=34.83+8.010 X+ 0.01570 X 2 .
18. The paperboard of claim 16 wherein said basis weight is at most Y 4 ′ pounds per 3000 ft 2 , wherein Y 4 ′ is calculated as follows:
Y 4 ′=33.79+7.769 X+ 0.01524 X 2 .