FILLER SUSPENSION AND ITS USE IN THE MANUFACTURE OF PAPER
Provided herein are filler suspensions comprising an ionic starch, a complementary ionic coadditive and filler particles. Pulp furnishes comprising the filler suspensions and paper comprising the pulp furnish are also provided. Processes for making the filler suspensions and processes for their use in manufacturing paper are also provided.
1 . A filler suspension for use in papermaking, comprising filler particles, ionic starch and a complementary ionic coadditive.
2 . The filler suspension of claim 1 , wherein the filler particles are selected from the group consisting of clay, talc, synthetic silicates, sodium magnesium alumino silicate, sodium alumino silicate, ground calcium carbonate (GCC), chalk, precipitated calcium carbonate (PCC), ground calcium sulphate (GCS), precipitated calcium sulphate (PCS), titanium dioxide and combinations thereof.
3 . The filler suspension of claim 1 , wherein the ionic starch is raw ionic starch.
4 . The filler suspension of claim 1 , wherein the ionic starch is swollen ionic starch.
5 . The filler suspension of claim 1 , wherein the ionic starch is cooked ionic starch.
6 . The filler suspension of claim 1 , wherein the ionic starch is cationic.
7 . The filler suspension of claim 1 , wherein the ionic starch is anionic.
8 . The filler suspension of claim 1 , wherein the ionic starch is amphoteric.
9 . The filler suspension of claim 1 , wherein the ionic starch is selected from the group consisting of corn starch, rice starch, potato starch, cassava starch, tapioca starch, waxy corn starch, wheat starch, sorghum starch and waxy sorghum starch.
10 . The filler suspension of claim 4 , wherein the swollen ionic starch is formed by heating an aqueous suspension of raw starch at a gel point temperature of the raw starch ±10° C.
11 . The filler suspension of claim 4 , wherein the swollen ionic starch is formed by heating an aqueous suspension of raw starch in a temperature range from the gel point temperature of the starch to the gel point temperature of the starch plus 10° C.
12 . The filler suspension of claim 1 , wherein the complementary ionic coadditive is an anionic flocculant.
13 . The filler suspension of claim 12 , wherein the anionic flocculant comprises a copolymer of acrylamide and sodium acrylate.
14 . The filler suspension of claim 13 , wherein the complementary ionic coadditive is selected from the group consisting of NALCO 61815, Nalco 61816, Nalco 61830, Fennosil® ES210 and Fennosil® ES211.
15 . The filler suspension of claim 1 , wherein the complementary ionic coadditive is an anionic inorganic microparticle.
16 . The filler suspension of claim 15 , wherein the anionic inorganic particle is selected from the group consisting of bentonites, colloidal silicas, sodium borosilicates, aluminium hydroxides or combinations thereof.
17 . The filler suspension of claim 1 , wherein the complementary ionic coadditive is selected from the group consisting of nanocellulose, polyvinyl alcohol, anionic PVAm, amphoteric PVAm, anionic polyacrylic acid, a sodium salt of polyacrylic acid, a biopolymer, a natural polymer and combinations thereof.
18 . The filler suspension of claim 17 , wherein the biopolymer is starch-based.
19 . The filler suspension of claim 18 , wherein the starch-based biopolymer is EcoSphere®2202 binder.
20 . The filler suspension of claim 17 , wherein the natural polymer is selected from the group consisting carboxymethylcellulose, natural gums, soy polymers and combinations thereof.
21 . The filler suspension of claim 1 , wherein the the filler particles are precipitated calcium carbonate.
22 . A pulp furnish, comprising pulp fiber and a filler suspension of claim 1 .
23 . The pulp furnish of claim 22 , further comprising an additive selected form the group consisting of a sizing agent, a dry strength agent, a wet strength agent, a retention aid and other functional chemicals such as an optical brightening agent, a dye, a defoamer, a bioside and combinations thereof.
24 . A paper product, comprising the pulp furnish of claim 22 .