A method for producing a halogenated zinc phthalocyanine pigment includes a step of forming a halogenated zinc phthalocyanine crude pigment into a pigment. The halogenated zinc phthalocyanine crude pigment is obtained by deposition of a halogenated zinc phthalocyanine, which is synthesized by using a compound that generates an acid by reacting with water, and the step includes a pretreatment step of heating the halogenated zinc phthalocyanine crude pigment in water to obtain a halogenated zinc phthalocyanine prepigment having a pH of 5.0 or more.

A process for the production of a quinacridone pigment composition is provided. For use in environmentally friendly inks, the pigment composition offers high chroma, high color strength, and high dispersion stability. Also provided is a water- or alcohol-based environmentally friendly ink that contains a quinacridone pigment composition obtained through this process. According to the inventors' research, adding a quinacridone derivative to a quinacridone solid solution in two different steps in a process, during and after treatment for the control of crystals, gives the resulting pigment composition the color characteristics of high color strength and high chroma, as well as high dispersion stability. The present invention is based on these findings.

The present invention relates to a composition for coloring foods, beverages, animal feeds, cosmetics or drugs comprising 1) dissolved carotenoid emulsified as an oil-in-water emulsion using a first hydrocolloid and 2) crystalline carotenoid encapsulated in a second hydrocolloid, making it water-dispersible and thereby miscible with the oil-in-water emulsified carotenoid fraction, mixed in a ratio of between 1:10 to 10:1 and wherein the first hydrocolloid is native casein.

The present invention provides a process for producing a fine organic pigment having a very small primary particle size, and a fine organic pigment produced by the process; a process for producing a dispersion using the fine organic pigment, and a dispersion produced by the process; and a process for producing an ink using the dispersion. The present invention relates to [1] a process for producing a fine organic pigment, including step 1 of kneading a mixture prepared by blending a raw material organic pigment, a water-soluble inorganic salt, a water-soluble organic solvent and water with each other, the water being blended in an amount of not less than 0.6 part by mass and not more than 4.0 parts by mass on the basis of 100 parts by mass of the water-soluble inorganic salt; [2] a fine organic pigment produced by the process described in the above [1]; [3] a dispersion produced using the fine organic pigment described in the above [2]; [4] a process for producing a paste of a fine organic pigment, including step 2 of cleaning the kneaded mixture obtained in the step 1; [5] a process for producing a dispersion, including step 3 of subjecting the paste of the fine organic pigment produced by the process described in the above [4], an organic solvent and water to dispersing treatment; and [6] a process for producing an ink, including step 4 of mixing the dispersion produced by the process described in the above [5], with at least one material selected from the group consisting of water and an organic solvent.

A novel dry down buffer is provided for use in drying a plurality of fluorescent dye conjugates on a substrate for use in flow cytometry. The aqueous buffer comprises a water-soluble monomer; a protein stabilizer; a carbohydrate stabilizer; and a zwitterionic surfactant. When mixed with a multi-color panel comprising fluorescent polymer dye conjugates, dried on a substrate, and reconstituted with a biological sample, the buffer provides decreased aggregation of fluorescent polymer dye conjugates, and decreased non-specific binding of monocytes and granulocytes, when compared to use of a buffer without the water-soluble monomer or zwitterionic surfactant.

The present invention aims to provide a dispersant and a dispersion composition that exhibit high dispersing ability for nano-carbons such as, in particular, CNTs. The dispersant according to the present invention includes a polyalkylene oxide having a structural unit of the following chemical formula (1).

##STR00001##

In the chemical formula (1), L.sup.1 and L.sup.2 are each a straight-chain alkylene group that may have a substituent, Z is a linking group that links L.sup.1 and Ar, or alternatively, Z may not be present and L.sup.1 and Ar may be linked directly to each other, and Ar is represented by the following chemical formula (1a), (1b), or (1c).

##STR00002##

The present invention provides an aqueous pigment dispersion including a pigment, an anionic group-containing organic polymer compound, and bio-nanofibers having an average diameter of 1 nm or more and 100 nm or less and an aspect ratio of 100 or more, and also provides an aqueous ink using the aqueous pigment dispersion. The bio-nanofibers are preferably cellulose nanofibers or chitosan nanofibers. The anionic group-containing organic polymer compound is preferably at least one selected from the group consisting of acrylic resins having anionic groups, polyurethane resins having anionic groups, and polysaccharide derivatives having anionic groups.

The disclosure relates to the use of compounds of specific structure as defoaming wetting agents for aqueous coating systems, for example paints and varnishes. The disclosure is more particularly related to methods of reducing the surface tension and/or increasing the density of an aqueous coating system, which methods include adding alcohol propoxylates to an aqueous coating system. The alcohol propoxylates have the general structure RO(PO).sub.xH, in which R is a saturated alkyl radical having 7 to 10 C atoms, PO is a propylene oxide unit, and x is a number in the range from 4 to 6. The resulting aqueous coating composition has good wetting properties, but is low in foam, so it does not disrupt processing operations of the coating system.

Provided is a pigment composition that includes an isoindoline compound, has excellent dispersibility, weather resistance and heat resistance, and good storage stability, and is capable of forming images having high chroma and the like, the pigment composition including an isoindoline compound represented by formula (1) and an isoindoline compound represented by formula (2). Also provided are a colorant composition, a coating material, an ink, an ink set, a printed matter, and a packaging material. ##STR00001##

The aqueous ink includes a pigment, a resin dispersant and an aqueous medium. The pigment contains C.I. Pigment Orange 43. The aqueous ink has an absorbance ratio of 0.95 or more to 1.15 or less, which is represented by the following equation (1). An absorbance of 50% by mass of an upper layer when the aqueous ink is centrifuged at 217,000 G for 30 minutes at a pigment content of 1.5% by mass is less than 0.20 in a wavelength range of 350 nm or more to 550 nm or less.

[00001]$\begin{array}{cc}\mathrm{Absorbance}\mathrm{ratio}=\mathrm{absorbance}\mathrm{at}\mathrm{peak}\mathrm{around}\mathrm{wavelength}\mathrm{of}532\mathrm{nm}/\mathrm{absorbance}\mathrm{at}\mathrm{peak}\mathrm{around}\mathrm{wavelength}\mathrm{of}496\mathrm{nm}& \left(1\right)\end{array}$