Aqueous ink composition
AssigneeSakura Color Products Corporation
InventorsMasaru Iwahashi, Shigeyasu Inoue, Yoshinori Murata
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Abstract
The present invention provides an aqueous ink composition comprising: (a) at least one N,N,N',N'-tetrakis-(2-hydroxyalkyl)-ethylenediamine represented by the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represent a group of the formula ##STR2## and may be the same, or at least one of these groups may be different from the others, n being zero or an integer of 1 to 3, (b) a dye, (c) a hygroscopic water-soluble organic solvent, and (d) water. The aqueous ink composition of the invention is used for fountain pens, porous point pens, roller pens or like writing implements, and has an improved storage stability, continuous writability and solution stability.
Claims11
An aqueous ink composition comprising:
- (a) about 0.1 to about 20 wt.% of at least one N,N,N',N'-tetrakis-(2-hydroxyalkyl)-ethylenediamine represented by the formula ##STR5## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 each represent a group of the formula ##STR6## and may be the same, or at least one of these groups may be different from the others, n being zero or an integer of 1 to 3,
- (b) about 0.1 to about 30 wt.% of a water-soluble dye,
- (c) about 10 to about 40 wt.% of at least one hygroscopic water-soluble organic solvent, and
- (d) about 30 to about 80 wt.% of water.
Dependencies are inferred from the claim text.