Abstract: Disclosed herein is an ink-jet ink comprising in combination at least one compound selected from nitrogen compounds consisting of secondary amines and derivatives thereof, tertiary amines and derivative thereof, and complexes thereof and having at least one group selected from the group consisting of alkyl groups, a carboxyl group and the salts thereof, and a sulfonic group and the salts thereof, and a cyclic phosphate in a liquid medium in which a dye is dissolved or dispersed.

Abstract: Disclosed herein is a monoazo dye compound having a structural unit represented by the following formula in its molecule:--X--Y--(R.sub.1)(R.sub.2)(R.sub.3).sub.k [I]wherein Y is a 6-membered ring containing 2 or 3 nitrogen atoms, X is a linking group for bonding a main body of the dye molecule to Y, R.sub.1 is the first amino acid residue, R.sub.2 is an atomic group selected from the following group A, R.sub.3 is another atomic group selected from the following group BB, and k is a number of 0 or 1:Group A: H, OH, NH.sub.2, CN, .dbd.O and the second amino acid residue;Group BB: H, OH, NH.sub.2, CN and .dbd.O,the first and second amino acid residues being identical with or different from each other.

Abstract: Disclosed herein is an ink comprising a coloring material and a liquid medium dissolving the coloring material therein, wherein the ink comprises a dye having at least one ammonium ion as a counter ion and an ammonium salt of an inorganic or organic acid.

Abstract: An ink-jet method and apparatus employing an ink comprising a dye and a liquid medium for dissolving or dispersing a dye, wherein the liquid medium comprises an alkyl alcohol having 2 to 4 carbon atoms, in which at least one of the hydrogen atoms is substituted by a halogen atom.

Abstract: An ink comprising a dye and a liquid medium for dissolving or dispersing a dye, wherein the liquid medium comprises an alkyl alcohol having 2 to 4 carbon atoms, in which at least one of the hydrogen atoms is substituted by a halogen atom.

Abstract: Disclosed herein is an ink comprising a recording agent and a liquid medium dissolving or dispersing the recording agent therein, wherein the ink contains an imide compound and at least one compound selected from the group consisting of urea, thiourea and derivatives thereof, and volatile alkaline compounds.

Abstract: An ink tank having an ink storing portion encases an ink-absorbent member for holding ink. The ink-absorbent member comprises a porous material having therein compressed open cells. The compression ratio r.sub.1 of an apparent volume V.sub.1 before compression to an apparent volume V.sub.2 after compression (r.sub.1 =V.sub.1 /V.sub.2) and the cell number p represented by number of cells per inch in the state of V.sub.1 satisfy the relation (I) below, and p being not more than 60.100 [inch.sup.-1 ].ltoreq.r.sub.1 .multidot.p.ltoreq.200 [inch.sup.

Abstract: An ink that includes a recording agent and a liquid medium capable of dissolving or dispersing the recording agent. The ink contains a compound represented by the following Formula (I):R.sub.1 --CONH--R.sub.2 (I)wherein R.sub.1 represents an alkyl group or aryl group unsubstituted or substituted with a group selected from a hydroxyl group, a carboxyl group, a sulfone group, an amino group and an acetylamino group; and R.sub.2 represents a hydrogen atom, an amide group, an aminoalkyl group, an aliphatic carboxylic acid residual group, or an aryl group unsubstituted or substituted with a group selected from a hydroxyl group, a carboxyl group, a sulfone group, an amino group and an acetylamino group; provided that R.sub.1 represents the unsubstituted or substituted aryl group when R.sub.2 is a hydrogen atom. The ink is suitably used in ink-jet recording.

Abstract: An ink-jet recording process and apparatus employing ink that includes a recording agent and a liquid medium capable of dissolving or dispersing the recording agent, wherein said ink contains both a compound represented by the following Formula (I) and a compound represented by the following Formula (II): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 each represent an alkyl group or a hydroxyalkyl group, and any one of them may represent a hydrogen atom; X.sup.- represents an inorganic acid ion; R.sub.4 and R.sub.5 each represent a group selected from a hydrogen atom, an alkyl group and a hydroxyalkyl group; and R.sub.6 represents a group selected from a carboxyl group, a hydroxyl group, a sulfone group, an alkyl group and a hydrogen atom. The ink is suitably used in the ink-jet recording.

Abstract: An ink comprises a recording agent and a liquid medium capable of dissolving or dispersing the recording agent, wherein said ink contains a compound represented by the following Formula (I): ##STR1## wherein R.sub.1 and R.sub.2 each represent a group selected from a hydrogen atom, an alkyl group, a hydroxyl group and a carboxyl group; and R.sub.3 represents a monohydric hydroxyalkyl group. The ink is suitably used for ink-jet recording.

Abstract: An ink comprises a recording agent and a liquid medium capable of dissolving or dispersing the recording agent, wherein said ink contains both a compound represented by the following Formula (I) and a compound represented by the following Formula (II): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 each represent an alkyl group or a hydroxyalkyl group, and any one of them may represent a hydrogen atom; X.sup.- represents an inorganic acid ion; R.sub.4 and R.sub.5 each represent a group selected from a hydrogen atom, an alkyl group and a hydroxyalkyl group; and R.sub.6 represents a group selected from a carboxyl group, a hydroxyl group, a sulfone group, an alkyl group and a hydrogen atom. The ink is suitably used in the ink-jet recording.