Printable recording media

Abstract

A printable recording media having a weight that is below 75 gsm and that contains a blend of hardwood and softwood fibers, wherein the total fiber content is at least 80 wt % of the total weight of the recording media; and a polymeric-modified pigment carbon black in an amount representing from about 0.02 wt % to about 1 wt % of the total weight of the recording media. Also disclosed herein are methods for making the printable recording media and a printing method using the printable recording media.

Claims

1. A printable recording media having a weight that is below 75 gsm, comprising: a. a blend of hardwood fibers and softwood fibers, wherein the total fiber content is at least 80 wt % of the total weight of the media; b. and a polymeric-modified pigment carbon black in an amount representing from about 0.02 wt % to about 1 wt % of the total weight of the media.

2. The printable recording media according to claim 1 wherein the polymeric modified carbon black pigment is a self-dispersed black pigment that is modified to include at least one polymer chemically attached thereto.

3. The printable recording media according to claim 1 wherein the polymeric-modified pigment carbon black is formed by combining a carbon black pigment with polymers containing carboxylic groups selected from the group consisting of styrene-acrylic polymers, polyacrylic acid polymers, polymethacrylic acid polymers and styrene maleic anhydride polymers.

4. The printable recording media according to claim 1, further comprising optical brightener agents in an amount representing from about 0.1 wt % to about 3 wt % of the total weight of the recording media.

5. The printable recording media according to claim 1, further comprising bi-valent and/or multi-valent salts in an amount representing from about 0.1 wt % to about 5 wt % of the total weight of the recording media.

6. The printable recording media according to claim 1, further comprising fillers in an amount representing from about 3 wt % to about 25 wt % of the total weight of the media.

7. The printable recording media according to claim 1 wherein the polymeric-modified pigment carbon black is added to the blend of hardwood and softwood fibers in the wet end.

8. The printable recording media according to claim 1 wherein the polymeric-modified pigment carbon black is added to the blend of hardwood and softwood fibers as a surface sizing agent and is part of a surface sizing solution containing starch additives.

9. The printable recording media according to claim 1 wherein the polymeric-modified pigment carbon black is added to the blend of hardwood and softwood fibers as a surface sizing agent and is part of a surface sizing solution containing starch additives and optical brightener agents.

10. A method for making the printable recording media as described in claim 1, comprising: a. mixing a blend of hardwood fibers and softwood fibers with a polymeric-modified pigment carbon black in view of forming a pulp; b. pressing the pulp into a raw base paper; c. and removing water in view of obtaining the printable recording media.

11. The method according to claim 10 wherein optical brightener agents are added to the mix of hardwood and softwood fibers and polymeric-modified pigment carbon black.

12. A method for making the printable recording media as described in claim 1, comprising: a. obtaining a raw base paper by mixing a blend of hardwood and softwood fibers in view of forming a fiber mat; b. pressing the fiber mat into a raw base paper; c. pre-drying the raw base paper; d. applying a surface sizing solution containing starch additives and polymeric-modified pigment carbon black onto the raw base paper via a size press; e. drying the raw base paper in view of obtaining the printable recording media.

13. The method according to claim 12 wherein the surface sizing solution further encompasses optical brightener agents.

14. The method according to claim 12 wherein the surface sizing solution further encompasses optical brightener agents and bi-valent and/or multi-valent salts.

15. A printing method for the printable recording media as defined in claim 1, the method comprising: a. obtaining a media having a weight that is below 75 gsm and that contains a blend of hardwood fibers and softwood fibers in an amount of at least 80 wt % and a polymeric-modified pigment carbon black in an amount representing from about 0.02 wt % to about 1 wt % of the total weight of the recording media; b. applying an ink composition onto said media to form a printed image.

Description

EXAMPLES

1. Samples Making Process and Formulations

(1) a. Fiber Furnish Pre-Mix

(2) Different recording media samples are prepared having a fiber mix (raw base paper) according to the specifications outlined in Table 1 below. Each media samples contain a blend of 60% hardwood Kraft pulp fibers, 30% softwood Kraft pulp fibers and 10% thermo-mechanical pulp (TMP) fibers. Pre-refined pulp slurries of each pulp are obtained from Western Michigan University Pilot Plants Facility.

(3) TABLE-US-00001 TABLE 1 Pre-mix Consistency Furnish (Solids %) Parts Hardwood 1.70% 60 Softwood 1.73% 30 TMP 3.25% 10 Total 1.83% 100

(4) Polymeric-modified pigment carbon black and optical brightener agent (Tinopal available from BASF) are then added in to the fiber mix shown in Table 1. Table 2 illustrates the solid content (in %) of each ingredient.

(5) TABLE-US-00002 TABLE 2 Polymeric- Furnish Modified Pigment Chemicals Pre-Mix Carbon Black Tinopal Solids (%) 1.83% 15.05% 35.54%
b. Media Prepared With Wetend (Internal) Application

(6) The media samples 1 to 10 are prepared by adding the polymeric treated carbon black pigment and optical brightener agent in the fiber mix in a wetend internal application. The final mix is diluted to 0.6% consistency (solids %) and 200 mL of the solution is used to make the handsheet using a standard 159 mm diameter sheet machine with target basis weight of 60 gsm. The quantity of ingredients added in each media samples and the final basis weight (in gsm) are illustrated in Table 3 below.

(7) TABLE-US-00003 TABLE 3 Polymeric Furnish Treated Carbon Formulation Recipe Black Pigment OBA Basis wt ID (dry parts) (dry parts) (dry parts) (gsm) Sample 1 100 63.3 Sample 2 100 0.05 60.3 Sample 3 100 0.1 59.8 Sample 4 100 0.2 61.0 Sample 5 100 0.05 0.5 58.8 Sample 6 100 0.1 0.5 62.5 Sample 7 100 0.2 0.5 62.8 Sample 8 100 0.05 1 62.3 Sample 9 100 0.1 1 61.0 Sample 10 100 0.2 1 61.0
c. Media Prepared With Surface Sizing Formulation

(8) Surface sizing compositions (a) to (f) are prepared according to the formulations listed in Table 4. All ingredients are illustrated according to their dry parts. Surface sizing compositions (a) to (f) are prepared by adding a starch solution into container containing water and mixing it for about 2 minutes. Starch (PenfordGum 280 available from Penford Products) is cooked separately in water for 20 min at 90 C. with agitation. The polymeric modified pigment carbon black is then added and mixed for 1 to 2 minutes. When present, optical brightener agents and CaCl.sub.2 are added separately and mixed independently for 1 to 2 minutes. Surface sizing compositions (a) to (f) are then applied to the sheets of 60 gsm raw base paper as outlined in Table 1, using a Mayer rod#8 size press, and dried using heat gun for 1 min. Media samples A to F are then obtained accordingly.

(9) TABLE-US-00004 TABLE 4 Surface Sizing Formulations (a) (b) (c) (d) (e) (f) Penford Gum 280 100 100 100 100 100 100 Polymeric Modified 0.1 0.3 0.5 0.1 0.5 Pigment Carbon Black Tinopal 0.5 0.5 CaCl2 15 15 Total Parts 100 100.1 100.3 100.5 115.6 116 Solids (%) 4.84 4.67 4.58 4.66 5.08 4.64 Brookfield Viscosity 47.1 38.1 39 35.4 24 21.3 (cP), S62, 100 rpm

2. Media Performances

(10) The media samples 1 to 10 and A to F are evaluated for their Brightness and Opacity. TAPPI Brightness is measured using TAPPI Standard T452, Brightness of pulp, paper and paperboard (directional reflectance at 457 nm). The opacity is tested using TAPPI test method T425. In accordance with this test method, a reflectance measurement is made on a sheet of paper backed by a black backing, R.sub.0. Another reflectance measurement is made on the sheet backed by an 89% reflective tile, R.sub.0.89. Opacity=100R.sub.0/R.sub.0.89. Higher opacity values indicate that it is more difficult to see through the sheet of paper. The normalized opacity or normalized brightness are obtained from the opacity or brightness multiplied by target basis weight (here, 60 gsm plain paper sheet) and divided by the actual basis weight in grams per square meter.

(11) Table 5 illustrates performance results for media samples 1 to 10 (i.e. obtained when ingredients are added in wetend). Table 6 illustrates performance results for media samples A to H (obtained when ingredients are added on surface application). The applied weight of the Polymeric Modified Pigment Carbon Black, Tinopal (OBA) and CaCl2 are calculated based on the total pickup as shown in the Table 6.

(12) TABLE-US-00005 TABLE 5 Normalized Normalized Tappi Brightness Sample Opacity (%) ID (%) Front Back Sample 1 76.4 80.0 80.0 Sample 2 79.1 83.6 83.5 Sample 3 80.2 82.1 82.2 Sample 4 79.8 79.2 79.6 Sample 5 80.3 92.3 92.0 Sample 6 76.8 85.0 85.0 Sample 7 77.6 83.0 82.7 Sample 8 77.6 85.8 86.2 Sample 9 78.7 87.0 87.1 Sample 10 79.2 85.6 85.8

(13) TABLE-US-00006 TABLE 6 Polymeric Modified Tappi Carbon Black Tinopal CaCl2 Opacity Brightness Media (gsm) (gsm) (gsm) (%) (%) Sample A 0 0 0 82.7 93.1 Sample B 0.002 0 0 83.0 93.7 Sample C 0.011 0 0 83.7 93.0 Sample D 0.024 0 0 84.0 92.5 Sample E 0.004 0.021 0.636 82.9 93.7 Sample F 0.013 0.013 0.392 83.8 92.6