Ink fixative solutions
The present disclosure is drawn to ink fixative solutions, which can consist essentially of a polyvalent metal salt, a holdout additive, and water. The polyvalent metal salt can be present in an amount from about 1 wt % to about 5 wt %, with respect to the entire weight of the ink fixative solution. The holdout additive can be present in an amount from about 2 wt % to about 20 wt %, with respect to the entire weight of the ink fixative solution. The holdout additive can be polyethylene glycol, glycerol, carboxy methyl cellulose, hydroxy ethyl cellulose, a fatty acid, a fatty acid ethoxylate, or combinations thereof.
1. A method of making an ink fixative treated substrate, comprising: forming a moist paper web having a first water content from about 15 wt % to about 60 wt %; applying an ink fixative solution to the moist paper web to form an ink fixative treated moist paper web, wherein the ink fixative solution consists essentially of: a polyvalent metal salt, a holdout additive, wherein the holdout additive is a polyethylene glycol, glycerol, carboxy methyl cellulose, hydroxy ethyl cellulose, a fatty acid, a fatty acid ethoxylate, or combinations thereof, and water; and reducing the water content of the ink fixative treated moist paper web to a final water content that is less than the first water content to form the ink fixative treated substrate.
2. The method of claim 1 , wherein the polyvalent metal salt is present in an amount from about 1 wt % to about 5 wt %, with respect to the entire weight of the ink fixative solution and the holdout additive is present in an amount from about 2 wt % to about 20 wt %, with respect to the entire weight of the ink fixative solution.
3. The method of claim 1 , wherein a weight ratio of the holdout additive to the polyvalent metal salt is from about 2:1 to about 11:1.
4. The method of claim 1 , wherein applying the ink fixative solution comprises spraying the ink fixative solution onto the moist paper web.
5. The method of claim 4 , wherein the moist paper web has been partially dried using a first dryer before the ink fixative solution is sprayed onto the moist paper web, and wherein reducing the water content of the ink fixative treated moist paper web comprises further drying the ink fixative treated moist paper web with a second dryer.
6. The method of claim 1 , wherein the ink fixative treated substrate is devoid of sizing agents other than the ink fixative solution.
7. The method of claim 1 , wherein the ink fixative treated substrate is a liner paper.
8. The method of claim 7 , further comprising printing a pigmented ink on the liner paper and bonding the liner paper together with a fluted medium after printing.
9. The method of claim 1 , wherein the first water content is from about 20 wt % to about 40 wt %.
10. The method of claim 1 , wherein applying the ink fixative solution comprises spraying the ink fixative solution onto the moist paper web, and wherein a weight ratio of the holdout additive to the polyvalent metal salt is from about 2:1 to about 11:1.
11. The method of claim 1 , wherein the holdout additive is carboxy methyl cellulose, hydroxyl ethyl cellulose, a fatty acid, a fatty acid ethoxylate, or combinations thereof.
12. The method of claim 1 , wherein the polyvalent metal salt is calcium chloride, magnesium chloride, magnesium sulfate, calcium nitrate, magnesium nitrate, magnesium acetate, zinc acetate, calcium propionate, or a combination thereof.