Low basis weight inkjet printable substrates with lower showthrough and improved waterfastness and print density

A method for preparing a printable substrate, which comprises the following steps:

• (a) providing a paper substrate having a first surface and a second surface and having a basis weight of from about 12 to about 32 lbs/1300 ft2, the paper substrate comprising:
• paper fibers in an amount in the range of from about 60 to 100% by weight of the paper substrate;
• and
• a substrate filler in an amount in the range of from 0 to about 30% by weight of the paper substrate;
• and
• (b) forming on at least one of the first and second surfaces a surface size layer to provide the printable substrate having a showthrough value of about 0.14 or less, and an opacity value of at least about 88%;
• (c) wherein the surface size layer of step (b) comprises about 50 lbs or less per ton of the paper substrate of a starch surface sizing agent;
• (d) wherein the surface size layer of step (b) comprises a multivalent metal salt drying agent in an amount sufficient to impart to the at least one of the first and second surfaces a black print density value of at least about 0.8 when inkjet printed with pigmented inks and a waterfastness value of at least about 85% when inkjet printed with dye-based inks;
• (e) wherein the printable substrate of step (b) has a MD tensile strength of at least about 12 lbs/in. and a CD tensile strength of at least about 6 lbs/in.