Abstract: A recording liquid including a pigment, a water-soluble resin, a water-soluble organic solvent, and water, wherein, of the water-soluble resin, water-soluble resin that is in the state of being dissolved in the recording liquid without being absorbed on the pigment is contained in an amount of not more than 2% by weight; and the water-soluble organic solvent comprises at least one of a polyhydric alcohol and an alkyl ether thereof, and an aliphatic monohydric alcohol. This recording liquid is used in an ink-jet recording method, recording unit, ink cartridge, and ink-jet recording apparatus.

Abstract: An ink comprising an aqueous liquid medium which contains acid carbon black having a volatile content within the range of 3.5 to 8% by weight and a water-soluble resin having a weight average molecular weight within the range of 3,000 to 30,000, wherein the weight ratio of the acid carbon black to the water-soluble resin is within the range of 3:1 to 10:1. The present invention also relates to an ink jet recording method, and ink jet device, an ink cartridge and an ink jet recording apparatus which uses the ink.

Abstract: An ink comprising a composition containing a pigment, a water-soluble resin and a liquid medium, wherein the pigment and the water-soluble resin are contained in said composition in a proportion of the weight Wr of the latter to the weight Wp of the former, Wr/Wp, that satisfies the expression (I) ##EQU1## wherein DAR denotes a value represented by the expression (II) ##EQU2##

Abstract: A recording liquid including a pigment, a water-soluble resin, a water-soluble organic solvent, and water, wherein, of the water-soluble resin, water-soluble resin that is in the state of being dissolved in the recording liquid without being absorbed on the pigment is contained in an amount of not more than 2% by weight; and the water-soluble organic solvent comprises at least one of a polyhydric alcohol and an alkyl ether thereof, and an aliphatic monohydric alcohol. This recording liquid is used in an ink-jet recording method, recording unit, ink cartridge, and ink-jet recording apparatus.

Abstract: There is disclosed a method for forming a color image by use of a plurality of color inks containing a cyan ink, wherein there is used an ink as the cyan ink which contains a metallophthalocyanine dye and/or a metal-free phthalocyanine dye and which contains free ions of divalent or higher metals at the concentration of 15 ppm or less, the methallophthalocyanine dye having a coordination metal selected from the metal atoms of the groups, IIA, IVB, VA, VIIA and VIII of the periodic Table of The Elements at the center of its skeleton, and the metal-free phthalocyanine dye having no coordination metal at the center of its skeleton, and also an ink to be used therefor.

Abstract: A naphthalene trisazo compound represented by the general formula (I) or (II): ##STR1## wherein A and B each represents a substituted or unsubstituted benzene or naphthalene ring; m represents zero or 1; and M represents an alkali metal atom, ammonium or H.Am (wherein Am represents an amine); or ##STR2## wherein X represents a hydrogen atom, a lower alkyl group, a phenyl group or a phenyl group substituted by --SO.sub.3 M; m represents zero or 1; M represents an alkali metal atom, ammonium or H.Am (wherein Am represents an amine); A, B and C each represents a substituted or an unsubstituted benzene or naphthalene ring, provided that B and C do not represent a naphthalene ring at the same time. A recording liquid containing these compounds is suitable for use in an ink-jet recording system.

Abstract: A recording liquid comprising a solution of a recording agent is provided. The recording agent has a structure containing a plural number of structural units linked together through a linking group or groups. The structural unit may be a dye residue.

Abstract: A black recording liquid suitable for use in ink-jet recording or as an ink for writing instruments comprises at least two water-soluble dyes and a liquid medium. Each of the dyes satisfies the condition defined by the following expression [I], and a mixture of these dyes satisfies the condition defined by the following expression [II]. ##EQU1## In these expressions, a* and b* are chromaticness indices defined in the CIE 1976 (L*, a*, b*) space, i indicates the ith dye of the dyes used together, and n is an integer of 2 or more.

Abstract: A functional optical element comprises a first optical member, a second optical member provided in contact with said first optical member, the interface between said first optical member and said second optical member being non-flat planar, a means for changing the refractive index of said second optical member, said means for changing refractive index being capable of creating selectively a first state in which said first optical member and said second optical member have an equal refractive index and a second state in which said first optical member and said second optical member have different refractive indices by changing the refractive index of said second optical member.

Abstract: A naphthalenedisazoic dye represented by general formula (I); ##STR1## wherein Q represents ##STR2## or a naphthalene group substituted by --SO.sub.3 M; R represents a methyl group, a methoxy group, an ethoxy group; X represents a hydrogen atom, a phenyl group substituted by --SO.sub.3 M; m represents 1 or 2; n represents 1 when X represents a hydrogen atom and n represents zero when X represents a phenyl group substituted by --SO.sub.3 M, wherein X represents a hydrogen atom and m represents 1 when Q represents a naphthalene group substituted by --SO.sub.3 M; and M represents an alkali metal atom, an ammonium, or H.A (wherein A represents an amine), and a recording liquid containing the dye. The recording liquid is suitable for use in an ink-jet recording system.

Abstract: An optical modulator having a layer of optical modulating substance between a pair of electrode-supporting plates is provided, which is characterized in that at least one of the electrode-supporting plates is provided with a mark for registration and the other substrate is provided with a projection for registration at the position corresponding to that of the mark for registration.