Paper products

1. A paper product, comprising: a paperboard comprising a substrate layer, a filler layer, and a cap layer, wherein the filler layer is disposed between the substrate layer and the cap layer, wherein: the filler layer includes about 15% weight to about 25% weight of a filler material, the cap layer includes a polylactic acid based resin, and the cap layer is substantially free of the filler material.

2. The paper product of claim 1 , wherein the filler material is selected from the group consisting of: calcium carbonate, TiO 2 , BaSO 4 , clay, kaolin, silica, Mg-Al-silicate, styrene-based resin, acrylic resin, styrene-acrylic copolymer resin, vinyl chloride, polycarbonate, mica, sodium carbonate, potassium carbonate, barium carbonate, sodium silicate, sodium borosilicate, magnesium oxide, strontium oxide, barium oxide, a zeolite, silicon dioxide, magnesium oxide, calcium oxide, barium oxide, and combinations thereof.

3. The paper product of claim 1 , wherein the filler material is calcium carbonate.

4. The paper product of claim 1 , wherein the filler layer includes a polylactic acid based resin, wherein the polylactic acid based resin is about 30 to 80% weight of the filler layer.

5. The paper product of claim 4 , wherein the filler layer includes a polyester material selected from the group consisting of: polycaprolactone (PCL), polyvalerolactone (PVL), poly(lactide-co-glycolide) (PLGA), polybutyrolactone (PBL), polyglycolide, polypropiolactone (PPL), poly(butylene terephthalate) (PBT), polybutylene adipate terephthalate (PBAT), poly butanediol adipic acid (PBA), and combinations thereof.

6. The paper product of claim 5 , wherein the filler layer further includes about 2% to about 30% weight of the polyester material.

7. The paper product of claim 1 , wherein the polylactic acid based resin is about 40 to 100% weight of the cap layer.

8. The paper product of claim 1 , wherein the cap layer includes a polyester material selected from the group consisting of: polycaprolactone (PCL), polyvalerolactone (PVL), poly(lactide-co-glycolide) (PLGA), polybutyrolactone (PBL), polyglycolide, polypropiolactone (PPL), poly(butylene terephthalate) (PBT), polybutylene adipate terephthalate (PBAT), poly butanediol adipic acid (PBA), and combinations thereof.

9. The paper product of claim 1 , wherein the substrate layer is made of papermaking fibers.

10. The paper product of claim 1 , wherein the paper product is selected from the group consisting of: a hot cup, a food wrap, a sleeve, and a paper product having heat seal applications, wherein a portion of the cap layer is disposed on an inner surface of the paper product and contacts a food product.

11. A paper product, comprising: a paperboard comprising a substrate layer, a first filler layer, a second filler layer, a first cap layer, and a second cap layer, wherein the substrate layer is disposed between the first filler layer and the second filler layer, wherein the first filler layer is disposed between the first cap layer and the substrate layer, wherein the second filler layer is disposed between the second cap layer and the substrate layer, wherein each of the first filler layer and the second filler layer includes a filler material, wherein the first cap layer and the second cap layer includes a polylactic acid based resin, and wherein each of the first cap layer and the second cap layer is substantially free of the filler material.

12. The paper product of claim 11 , wherein the filler material is selected from the group consisting of: calcium carbonate, kaolin, clay, mica, talc, and combinations thereof.

13. The paper product of claim 11 , wherein at least one filler layer includes a polyester material selected from the group consisting of: polycaprolactone (PCL), polyvalerolactone (PVL), poly(lactide-co-glycolide) (PLGA), polybutyrolactone (PBL), polyglycolide, polypropiolactone (PPL), poly(butylene terephthalate) (PBT), polybutylene adipate terephthalate (PBAT), poly butanediol adipic acid (PBA), and combinations thereof.

14. The paper product of claim 13 , wherein at least one filler layer further comprises a polylactic acid based resin.

15. The paper product of claim 13 , wherein at least one filler layer further comprises about 30% to about 80% weight of a polylactic acid based resin.

16. The paper product of claim 15 , wherein at least one filler layer comprises about 2% to about 30% weight of the polyester material.

17. The paper product of claim 16 , wherein each of the first filler layer and the second filler layer comprises about 15% to about 25% weight of the filler material and about 55% to about 80% weight of the polylactic acid based resin.

18. The paper product of claim 11 , wherein each of the first filler layer and the second filler layer comprises about 15% to about 25% weight of the filler material.

19. A paper product, comprising: a paperboard comprising a substrate layer, a filler layer, and a cap layer, wherein the filler layer is disposed between the substrate layer and the cap layer, wherein the filler layer includes about 15% weight to about 25% weight of a filler material, wherein the cap layer includes a polyester material selected from the group consisting of: polycaprolactone (PCL), polyvalerolactone (PVL), poly(lactide-co-glycolidede) (PLGA), polybutyrolactone (PBL), polyglycolide, polypropiolactone (PPL), poly(butylene terephthalate) (PBT), polybutylene adipate terephthalate (PBAT), poly butanediol adipic acid (PBA), polylactic acid (PLA), and combinations thereof, and wherein the cap layer is substantially free of the filler material.

20. The paper product of claim 19 , wherein the filler layer further comprises a polylactic acid based resin and comprises about 2% to about 30% weight of the polyester material.