Paper surface sizing composition, sized paper, and method for sizing paper

An article comprising:

• a paper web having first and second surfaces;
• and
• a paper surface size coating on at least one of the first and second surfaces,
• wherein the paper surface size coating provides a paper surface size loading on each surface on which the paper surface size coating is present is in an amount from about 0.5 to about 4 gsm;
• wherein the paper surface size coating comprises:
• an acicular calcium carbonate paper pigment having an aspect ratio in the range of from about 2 to about 12 and a low particulate surface area;
• a paper starch binder;
• and
• a paper co-binder;
• wherein the starch binder comprises from about 40 to about 95% by weight of the total combined weight of the starch binder and the co-binder;
• wherein the co-binder comprises from about 5 to about 60% by weight of the total combined weight of the starch binder and the co-binder;
• and
• wherein the pigment to starch binder/co-binder weight ratio is in the range of from about 0.75 to about 3.

A method comprising the following steps:

• (a) providing an uncoated or a single-side coated paper web having first and second surfaces;
• and
• (b) providing a liquid paper surface sizing composition comprising:
• an acicular calcium carbonate paper pigment having an aspect ratio in the range of from about 4 to about 10 and a low particulate surface area;
• a paper starch binder;
• and
• a paper co-binder;
• wherein the starch binder comprises from about 50 to about 95% by weight of the total combined weight of starch and co-binder;
• wherein the co-binder comprises from about 5 to about 50% by weight of the total combined weight of the starch binder and the co-binder;
• wherein the pigment to starch binder/co-binder weight ratio is in the range of from about 1 to about 3;
• wherein the composition has a Brookfield viscosity in the range of from about 30 to about 300 centipoise;
• wherein the composition has a solids content of at least about 12% by weight;
• and
• (c) treating at least one of the first and second surfaces of the paper web of step (a) with the paper surface size composition of step (b), wherein the paper surface size loading on each surface on which the paper surface size coating is present is in an amount from about 0.5 to about 4 gsm.