The present invention refers to a process for the preparation of a graphene dispersion comprising the following steps: i) providing cellulose acetate flakes or powders; ii) swelling the cellulose acetate flakes or powders in an alcohol having from 1 to 3 carbon atoms; iii) adding acetic anhydride in a concentration range from 30 to 50 wt % referred to the total weight of the mixture; iv) adding graphene nanoplatelets to yield a graphene dispersion. The graphene dispersion is used as ink for composite materials that are employed in the field of foldable electronics. The invention relates also to a composite material comprising uniformly dispersed graphene nanoplatelets and its use for manufacturing electronic devices

There is provided a water-based ink for ink-jet recording including: a self-dispersible black pigment; a resin-dispersed chromatic pigment including a resin-dispersed magenta pigment and a resin-dispersed cyan pigment; and water. A ratio (Col/Bk) of a solid content mass (Col) of the resin-dispersed chromatic pigment to a solid content mass (Bk) of the self-dispersible black pigment is in a range of 0.24 to 0.73 and a mean particle diameter of the self-dispersible black pigment is greater than a mean particle diameter of the resin-dispersed chromatic pigment.

There is provided a water-based ink for ink-jet recording including: a self-dispersible black pigment; a resin-dispersed chromatic pigment including a resin-dispersed magenta pigment and a resin-dispersed cyan pigment; and water. A ratio (Col/Bk) of a solid content mass (Col) of the resin-dispersed chromatic pigment to a solid content mass (Bk) of the self-dispersible black pigment is in a range of 0.24 to 0.73 and a mean particle diameter of the self-dispersible black pigment is greater than a mean particle diameter of the resin-dispersed chromatic pigment.

A set includes: a water-based black pigment ink for ink-jet recording; a water-based yellow dye ink for ink-jet recording; a water-based magenta dye ink for ink-jet recording; a water-based cyan dye ink for ink-jet recording; and a treatment agent. The water-based black pigment ink for ink-jet recording includes a carbon black and water; the water-based yellow dye ink for ink-jet recording includes a yellow dye and water; the water-based magenta dye ink for ink-jet recording includes a magenta dye and water; the water-based cyan dye ink for ink-jet recording includes a cyan dye and water; and the treatment agent includes a cationic polymer emulsion.

A set includes: a water-based black pigment ink for ink-jet recording; a water-based yellow dye ink for ink-jet recording; a water-based magenta dye ink for ink-jet recording; a water-based cyan dye ink for ink-jet recording; and a treatment agent. The water-based black pigment ink for ink-jet recording includes a carbon black and water; the water-based yellow dye ink for ink-jet recording includes a yellow dye and water; the water-based magenta dye ink for ink-jet recording includes a magenta dye and water; the water-based cyan dye ink for ink-jet recording includes a cyan dye and water; and the treatment agent includes a cationic polymer emulsion.

An ink set includes an ink A including water, an organic solvent A, a self-dispersible pigment, an anionic resin particle, and an amine compound having a boiling point of 120 degrees C.-200 degrees C. and an ink B including water, an organic solvent B, and a resin-coated pigment, wherein when the mass content of the amine compound is determined as 1, the mass content of the anionic resin particle is 1-100 and the mass content of the resin-coated pigment is 10-200, while the mass content of the anionic resin particle and the mass content of the resin-coated pigment are respectively based on the content per unit of mass of the ink A and the content per unit of mass of the ink B.

An ink set includes an ink A including water, an organic solvent A, a self-dispersible pigment, an anionic resin particle, and an amine compound having a boiling point of 120 degrees C.-200 degrees C. and an ink B including water, an organic solvent B, and a resin-coated pigment, wherein when the mass content of the amine compound is determined as 1, the mass content of the anionic resin particle is 1-100 and the mass content of the resin-coated pigment is 10-200, while the mass content of the anionic resin particle and the mass content of the resin-coated pigment are respectively based on the content per unit of mass of the ink A and the content per unit of mass of the ink B.

A water-based ink set for ink-jet recording includes: a water-based yellow ink containing a yellow pigment, a resin dispersant, and water; a water-based magenta ink containing a magenta pigment, a resin dispersant, and water; a water-based cyan ink containing a cyan pigment, a resin dispersant, and water; and a water-based black ink containing self-dispersible carbon black and water. At least one water-based color ink selected from the group consisting of the water-based yellow ink, the water-based magenta ink, and the water-based cyan ink further contains a dye. The self-dispersible carbon black has an average particle size of 120 to 170 nm.

A water-based ink set for ink-jet recording includes: a water-based yellow ink containing a yellow pigment, a resin dispersant, and water; a water-based magenta ink containing a magenta pigment, a resin dispersant, and water; a water-based cyan ink containing a cyan pigment, a resin dispersant, and water; and a water-based black ink containing self-dispersible carbon black and water. At least one water-based color ink selected from the group consisting of the water-based yellow ink, the water-based magenta ink, and the water-based cyan ink further contains a dye. The self-dispersible carbon black has an average particle size of 120 to 170 nm.

An inkjet ink includes a self-dispersing pigment, specific particles and an aqueous medium. The specific particles include a pigment and a resin. In the specific particles, the mass ratio of the resin to the pigment is equal to or greater than 1.2 and equal to or less than 2.0. The resin includes a styrene-(meth)acrylic resin. The volume median diameter of the specific particles is equal to or greater than 100 nm and equal to or less than 170 nm.