The present invention relates to a magenta ink for inkjet recording containing at least one pigment selected from the group consisting of C.I. Pigment Red 147, 150, 176, 266 and 269, in an amount of 0.5 to 10% by mass relative to the total mass of the ink. The present invention can provide a magenta ink that is comprehensively superior in terms of light resistance, color development and storage stability. The present invention can also provide an ink set having excellent light resistance and color development for each ink included in the ink set, and an inkjet recording method that uses the ink set.

A method for producing a sol-gel ink, in particular from TEOS and MTEOS, is provided. The method includes adding inorganic particles as a filler and adding a high-boiling solvent.

A method is provided for making thermochromic pigments in microcapsules having unusually small particle sizes.

Colored fluids for electrowetting, electro fluidic, or electrophoretic devices, and the devices themselves, are disclosed. The colored fluid can include a nonaqueous polar solvent having (a) a dynamic viscosity of 0.1 cP to 50 cP at 250 C, (b) a surface tension of 25 dynes/cm to 55 dynes/cm at 250 C, and (c) an electrowetting relative response of 40% to 80%. Such colored fluids further include a colorant selected from a pigment and/or a dye. In another embodiment, the colored fluid can include a non-polar solvent and an organic colorant selected from a pigment and/or a dye. Such colored fluids can be black in color and have a conductivity from 0 pS/cm to 5 pS/cm and a dielectric constant less than 3. The use of the colored fluids offers improvements in reliability, higher levels of chroma in the dispersed state, and the ability to achieve higher contrast ratios in display technologies.

A coloring composition includes colorants, polymerizable compounds, and a resin, in which a ratio P/M of a mass P of the colorants to a mass M of the polymerizable compounds is 0.05 to 0.35, a content of the polymerizable compounds is 25 to 65 mass % with respect to a total solid content of the coloring composition, a ratio A/B of a minimum value A of an absorbance in a wavelength range of 400 nm or longer and shorter than 580 nm to a minimum value B of an absorbance in a wavelength range of 580 nm to 770 nm is 0.3 to 3, and a ratio C/D of a minimum value C of an absorbance in a wavelength range of 400 nm to 750 nm to a maximum value D of an absorbance in a wavelength range of 850 nm to 1300 nm is 5 or higher.

Dispersion is obtained by: blending a specific resin emulsion for protecting a tungsten-based infrared-absorbing pigment; and dispersing the tungsten-based infrared-absorbing pigment in a state of being coated in advance by means of the resin emulsion.

A curable resin composition for a lens, including a coloring agent A having a maximal absorption at a wavelength of 520 to 620 nm, in which a wavelength dispersion WD of a cured product of the composition, which is calculated by the following expression (X), is 2.010.sup.5 or more; a cured product formed of the curable resin composition for a lens; a diffractive optical element; and a multilayer diffractive optical element.
WD=(nCn(1129))/(1129656)Expression (X)
In the expression, nC represents a refractive index at a wavelength of 656 nm and n(1129) represents a refractive index at a wavelength of 1129 nm.

An aqueous ink composition for writing instruments containing an aqueous dispersion of colored resin fine particles, the colored resin fine particles containing at least a cyclohexyl (meth)acrylate monomer and a basic dye or an oil-soluble dye, the cyclohexyl (meth)acrylate monomer being contained in an amount of 30 mass % or greater relative to an amount of a polymerizable polymer component in the colored resin fine particles, and the colored resin fine particles further containing a terpene phenol resin.

An infrared-absorbing composition includes particles of an infrared-absorbing coloring agent and a solvent, in which the particles in the infrared-absorbing composition have two or more maximal absorption wavelengths exhibited in a wavelength range of 650 to 1500 nm, and in the range, in a case where an absorbance at a maximal absorption wavelength existing on a second shortest wavelength side is set to 1, an absorbance at a maximal absorption wavelength existing on a shortest wavelength side is 0.6 to 2.0.

An optical filter includes: a transparent substrate; and an absorption layer on the transparent substrate, the absorption layer containing at least one dye (X) having a maximum absorption wavelength in 600 to 1000 nm. A laminate of the transparent substrate and the absorption layer satisfies all of the following characteristics (i-2) to (i-4): (i-2) a maximum internal transmittance in 700 to 850 nm is 35% or lower; (i-3) a difference between the maximum internal transmittance and a minimum internal transmittance in 700 to 850 nm is 20% or smaller; and (i-4) OD(A) and OD(B) satisfy the following relationship: OD(A)/OD(B)<0.07 where OD(A) is an average optical density of an internal transmittance in 500 to 600 nm and OD(B) is an average optical density of an internal transmittance in 700 to 850 nm.